README 202 KB

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  1. #
  2. # (C) Copyright 2000 - 2013
  3. # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  4. #
  5. # SPDX-License-Identifier: GPL-2.0+
  6. #
  7. Summary:
  8. ========
  9. This directory contains the source code for U-Boot, a boot loader for
  10. Embedded boards based on PowerPC, ARM, MIPS and several other
  11. processors, which can be installed in a boot ROM and used to
  12. initialize and test the hardware or to download and run application
  13. code.
  14. The development of U-Boot is closely related to Linux: some parts of
  15. the source code originate in the Linux source tree, we have some
  16. header files in common, and special provision has been made to
  17. support booting of Linux images.
  18. Some attention has been paid to make this software easily
  19. configurable and extendable. For instance, all monitor commands are
  20. implemented with the same call interface, so that it's very easy to
  21. add new commands. Also, instead of permanently adding rarely used
  22. code (for instance hardware test utilities) to the monitor, you can
  23. load and run it dynamically.
  24. Status:
  25. =======
  26. In general, all boards for which a configuration option exists in the
  27. Makefile have been tested to some extent and can be considered
  28. "working". In fact, many of them are used in production systems.
  29. In case of problems see the CHANGELOG file to find out who contributed
  30. the specific port. In addition, there are various MAINTAINERS files
  31. scattered throughout the U-Boot source identifying the people or
  32. companies responsible for various boards and subsystems.
  33. Note: As of August, 2010, there is no longer a CHANGELOG file in the
  34. actual U-Boot source tree; however, it can be created dynamically
  35. from the Git log using:
  36. make CHANGELOG
  37. Where to get help:
  38. ==================
  39. In case you have questions about, problems with or contributions for
  40. U-Boot, you should send a message to the U-Boot mailing list at
  41. <u-boot@lists.denx.de>. There is also an archive of previous traffic
  42. on the mailing list - please search the archive before asking FAQ's.
  43. Please see http://lists.denx.de/pipermail/u-boot and
  44. http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
  45. Where to get source code:
  46. =========================
  47. The U-Boot source code is maintained in the Git repository at
  48. git://www.denx.de/git/u-boot.git ; you can browse it online at
  49. http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
  50. The "snapshot" links on this page allow you to download tarballs of
  51. any version you might be interested in. Official releases are also
  52. available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
  53. directory.
  54. Pre-built (and tested) images are available from
  55. ftp://ftp.denx.de/pub/u-boot/images/
  56. Where we come from:
  57. ===================
  58. - start from 8xxrom sources
  59. - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
  60. - clean up code
  61. - make it easier to add custom boards
  62. - make it possible to add other [PowerPC] CPUs
  63. - extend functions, especially:
  64. * Provide extended interface to Linux boot loader
  65. * S-Record download
  66. * network boot
  67. * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
  68. - create ARMBoot project (http://sourceforge.net/projects/armboot)
  69. - add other CPU families (starting with ARM)
  70. - create U-Boot project (http://sourceforge.net/projects/u-boot)
  71. - current project page: see http://www.denx.de/wiki/U-Boot
  72. Names and Spelling:
  73. ===================
  74. The "official" name of this project is "Das U-Boot". The spelling
  75. "U-Boot" shall be used in all written text (documentation, comments
  76. in source files etc.). Example:
  77. This is the README file for the U-Boot project.
  78. File names etc. shall be based on the string "u-boot". Examples:
  79. include/asm-ppc/u-boot.h
  80. #include <asm/u-boot.h>
  81. Variable names, preprocessor constants etc. shall be either based on
  82. the string "u_boot" or on "U_BOOT". Example:
  83. U_BOOT_VERSION u_boot_logo
  84. IH_OS_U_BOOT u_boot_hush_start
  85. Versioning:
  86. ===========
  87. Starting with the release in October 2008, the names of the releases
  88. were changed from numerical release numbers without deeper meaning
  89. into a time stamp based numbering. Regular releases are identified by
  90. names consisting of the calendar year and month of the release date.
  91. Additional fields (if present) indicate release candidates or bug fix
  92. releases in "stable" maintenance trees.
  93. Examples:
  94. U-Boot v2009.11 - Release November 2009
  95. U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
  96. U-Boot v2010.09-rc1 - Release candidate 1 for September 2010 release
  97. Directory Hierarchy:
  98. ====================
  99. /arch Architecture specific files
  100. /arc Files generic to ARC architecture
  101. /arm Files generic to ARM architecture
  102. /m68k Files generic to m68k architecture
  103. /microblaze Files generic to microblaze architecture
  104. /mips Files generic to MIPS architecture
  105. /nds32 Files generic to NDS32 architecture
  106. /nios2 Files generic to Altera NIOS2 architecture
  107. /openrisc Files generic to OpenRISC architecture
  108. /powerpc Files generic to PowerPC architecture
  109. /sandbox Files generic to HW-independent "sandbox"
  110. /sh Files generic to SH architecture
  111. /x86 Files generic to x86 architecture
  112. /api Machine/arch independent API for external apps
  113. /board Board dependent files
  114. /cmd U-Boot commands functions
  115. /common Misc architecture independent functions
  116. /configs Board default configuration files
  117. /disk Code for disk drive partition handling
  118. /doc Documentation (don't expect too much)
  119. /drivers Commonly used device drivers
  120. /dts Contains Makefile for building internal U-Boot fdt.
  121. /examples Example code for standalone applications, etc.
  122. /fs Filesystem code (cramfs, ext2, jffs2, etc.)
  123. /include Header Files
  124. /lib Library routines generic to all architectures
  125. /Licenses Various license files
  126. /net Networking code
  127. /post Power On Self Test
  128. /scripts Various build scripts and Makefiles
  129. /test Various unit test files
  130. /tools Tools to build S-Record or U-Boot images, etc.
  131. Software Configuration:
  132. =======================
  133. Configuration is usually done using C preprocessor defines; the
  134. rationale behind that is to avoid dead code whenever possible.
  135. There are two classes of configuration variables:
  136. * Configuration _OPTIONS_:
  137. These are selectable by the user and have names beginning with
  138. "CONFIG_".
  139. * Configuration _SETTINGS_:
  140. These depend on the hardware etc. and should not be meddled with if
  141. you don't know what you're doing; they have names beginning with
  142. "CONFIG_SYS_".
  143. Previously, all configuration was done by hand, which involved creating
  144. symbolic links and editing configuration files manually. More recently,
  145. U-Boot has added the Kbuild infrastructure used by the Linux kernel,
  146. allowing you to use the "make menuconfig" command to configure your
  147. build.
  148. Selection of Processor Architecture and Board Type:
  149. ---------------------------------------------------
  150. For all supported boards there are ready-to-use default
  151. configurations available; just type "make <board_name>_defconfig".
  152. Example: For a TQM823L module type:
  153. cd u-boot
  154. make TQM823L_defconfig
  155. Note: If you're looking for the default configuration file for a board
  156. you're sure used to be there but is now missing, check the file
  157. doc/README.scrapyard for a list of no longer supported boards.
  158. Sandbox Environment:
  159. --------------------
  160. U-Boot can be built natively to run on a Linux host using the 'sandbox'
  161. board. This allows feature development which is not board- or architecture-
  162. specific to be undertaken on a native platform. The sandbox is also used to
  163. run some of U-Boot's tests.
  164. See board/sandbox/README.sandbox for more details.
  165. Board Initialisation Flow:
  166. --------------------------
  167. This is the intended start-up flow for boards. This should apply for both
  168. SPL and U-Boot proper (i.e. they both follow the same rules).
  169. Note: "SPL" stands for "Secondary Program Loader," which is explained in
  170. more detail later in this file.
  171. At present, SPL mostly uses a separate code path, but the function names
  172. and roles of each function are the same. Some boards or architectures
  173. may not conform to this. At least most ARM boards which use
  174. CONFIG_SPL_FRAMEWORK conform to this.
  175. Execution typically starts with an architecture-specific (and possibly
  176. CPU-specific) start.S file, such as:
  177. - arch/arm/cpu/armv7/start.S
  178. - arch/powerpc/cpu/mpc83xx/start.S
  179. - arch/mips/cpu/start.S
  180. and so on. From there, three functions are called; the purpose and
  181. limitations of each of these functions are described below.
  182. lowlevel_init():
  183. - purpose: essential init to permit execution to reach board_init_f()
  184. - no global_data or BSS
  185. - there is no stack (ARMv7 may have one but it will soon be removed)
  186. - must not set up SDRAM or use console
  187. - must only do the bare minimum to allow execution to continue to
  188. board_init_f()
  189. - this is almost never needed
  190. - return normally from this function
  191. board_init_f():
  192. - purpose: set up the machine ready for running board_init_r():
  193. i.e. SDRAM and serial UART
  194. - global_data is available
  195. - stack is in SRAM
  196. - BSS is not available, so you cannot use global/static variables,
  197. only stack variables and global_data
  198. Non-SPL-specific notes:
  199. - dram_init() is called to set up DRAM. If already done in SPL this
  200. can do nothing
  201. SPL-specific notes:
  202. - you can override the entire board_init_f() function with your own
  203. version as needed.
  204. - preloader_console_init() can be called here in extremis
  205. - should set up SDRAM, and anything needed to make the UART work
  206. - these is no need to clear BSS, it will be done by crt0.S
  207. - must return normally from this function (don't call board_init_r()
  208. directly)
  209. Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at
  210. this point the stack and global_data are relocated to below
  211. CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of
  212. memory.
  213. board_init_r():
  214. - purpose: main execution, common code
  215. - global_data is available
  216. - SDRAM is available
  217. - BSS is available, all static/global variables can be used
  218. - execution eventually continues to main_loop()
  219. Non-SPL-specific notes:
  220. - U-Boot is relocated to the top of memory and is now running from
  221. there.
  222. SPL-specific notes:
  223. - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and
  224. CONFIG_SPL_STACK_R_ADDR points into SDRAM
  225. - preloader_console_init() can be called here - typically this is
  226. done by selecting CONFIG_SPL_BOARD_INIT and then supplying a
  227. spl_board_init() function containing this call
  228. - loads U-Boot or (in falcon mode) Linux
  229. Configuration Options:
  230. ----------------------
  231. Configuration depends on the combination of board and CPU type; all
  232. such information is kept in a configuration file
  233. "include/configs/<board_name>.h".
  234. Example: For a TQM823L module, all configuration settings are in
  235. "include/configs/TQM823L.h".
  236. Many of the options are named exactly as the corresponding Linux
  237. kernel configuration options. The intention is to make it easier to
  238. build a config tool - later.
  239. The following options need to be configured:
  240. - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
  241. - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
  242. - Marvell Family Member
  243. CONFIG_SYS_MVFS - define it if you want to enable
  244. multiple fs option at one time
  245. for marvell soc family
  246. - 85xx CPU Options:
  247. CONFIG_SYS_PPC64
  248. Specifies that the core is a 64-bit PowerPC implementation (implements
  249. the "64" category of the Power ISA). This is necessary for ePAPR
  250. compliance, among other possible reasons.
  251. CONFIG_SYS_FSL_TBCLK_DIV
  252. Defines the core time base clock divider ratio compared to the
  253. system clock. On most PQ3 devices this is 8, on newer QorIQ
  254. devices it can be 16 or 32. The ratio varies from SoC to Soc.
  255. CONFIG_SYS_FSL_PCIE_COMPAT
  256. Defines the string to utilize when trying to match PCIe device
  257. tree nodes for the given platform.
  258. CONFIG_SYS_FSL_ERRATUM_A004510
  259. Enables a workaround for erratum A004510. If set,
  260. then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
  261. CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
  262. CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
  263. CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
  264. Defines one or two SoC revisions (low 8 bits of SVR)
  265. for which the A004510 workaround should be applied.
  266. The rest of SVR is either not relevant to the decision
  267. of whether the erratum is present (e.g. p2040 versus
  268. p2041) or is implied by the build target, which controls
  269. whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
  270. See Freescale App Note 4493 for more information about
  271. this erratum.
  272. CONFIG_A003399_NOR_WORKAROUND
  273. Enables a workaround for IFC erratum A003399. It is only
  274. required during NOR boot.
  275. CONFIG_A008044_WORKAROUND
  276. Enables a workaround for T1040/T1042 erratum A008044. It is only
  277. required during NAND boot and valid for Rev 1.0 SoC revision
  278. CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
  279. This is the value to write into CCSR offset 0x18600
  280. according to the A004510 workaround.
  281. CONFIG_SYS_FSL_DSP_DDR_ADDR
  282. This value denotes start offset of DDR memory which is
  283. connected exclusively to the DSP cores.
  284. CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
  285. This value denotes start offset of M2 memory
  286. which is directly connected to the DSP core.
  287. CONFIG_SYS_FSL_DSP_M3_RAM_ADDR
  288. This value denotes start offset of M3 memory which is directly
  289. connected to the DSP core.
  290. CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
  291. This value denotes start offset of DSP CCSR space.
  292. CONFIG_SYS_FSL_SINGLE_SOURCE_CLK
  293. Single Source Clock is clocking mode present in some of FSL SoC's.
  294. In this mode, a single differential clock is used to supply
  295. clocks to the sysclock, ddrclock and usbclock.
  296. CONFIG_SYS_CPC_REINIT_F
  297. This CONFIG is defined when the CPC is configured as SRAM at the
  298. time of U-Boot entry and is required to be re-initialized.
  299. CONFIG_DEEP_SLEEP
  300. Indicates this SoC supports deep sleep feature. If deep sleep is
  301. supported, core will start to execute uboot when wakes up.
  302. - Generic CPU options:
  303. CONFIG_SYS_GENERIC_GLOBAL_DATA
  304. Defines global data is initialized in generic board board_init_f().
  305. If this macro is defined, global data is created and cleared in
  306. generic board board_init_f(). Without this macro, architecture/board
  307. should initialize global data before calling board_init_f().
  308. CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
  309. Defines the endianess of the CPU. Implementation of those
  310. values is arch specific.
  311. CONFIG_SYS_FSL_DDR
  312. Freescale DDR driver in use. This type of DDR controller is
  313. found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core
  314. SoCs.
  315. CONFIG_SYS_FSL_DDR_ADDR
  316. Freescale DDR memory-mapped register base.
  317. CONFIG_SYS_FSL_DDR_EMU
  318. Specify emulator support for DDR. Some DDR features such as
  319. deskew training are not available.
  320. CONFIG_SYS_FSL_DDRC_GEN1
  321. Freescale DDR1 controller.
  322. CONFIG_SYS_FSL_DDRC_GEN2
  323. Freescale DDR2 controller.
  324. CONFIG_SYS_FSL_DDRC_GEN3
  325. Freescale DDR3 controller.
  326. CONFIG_SYS_FSL_DDRC_GEN4
  327. Freescale DDR4 controller.
  328. CONFIG_SYS_FSL_DDRC_ARM_GEN3
  329. Freescale DDR3 controller for ARM-based SoCs.
  330. CONFIG_SYS_FSL_DDR1
  331. Board config to use DDR1. It can be enabled for SoCs with
  332. Freescale DDR1 or DDR2 controllers, depending on the board
  333. implemetation.
  334. CONFIG_SYS_FSL_DDR2
  335. Board config to use DDR2. It can be enabled for SoCs with
  336. Freescale DDR2 or DDR3 controllers, depending on the board
  337. implementation.
  338. CONFIG_SYS_FSL_DDR3
  339. Board config to use DDR3. It can be enabled for SoCs with
  340. Freescale DDR3 or DDR3L controllers.
  341. CONFIG_SYS_FSL_DDR3L
  342. Board config to use DDR3L. It can be enabled for SoCs with
  343. DDR3L controllers.
  344. CONFIG_SYS_FSL_DDR4
  345. Board config to use DDR4. It can be enabled for SoCs with
  346. DDR4 controllers.
  347. CONFIG_SYS_FSL_IFC_BE
  348. Defines the IFC controller register space as Big Endian
  349. CONFIG_SYS_FSL_IFC_LE
  350. Defines the IFC controller register space as Little Endian
  351. CONFIG_SYS_FSL_IFC_CLK_DIV
  352. Defines divider of platform clock(clock input to IFC controller).
  353. CONFIG_SYS_FSL_LBC_CLK_DIV
  354. Defines divider of platform clock(clock input to eLBC controller).
  355. CONFIG_SYS_FSL_PBL_PBI
  356. It enables addition of RCW (Power on reset configuration) in built image.
  357. Please refer doc/README.pblimage for more details
  358. CONFIG_SYS_FSL_PBL_RCW
  359. It adds PBI(pre-boot instructions) commands in u-boot build image.
  360. PBI commands can be used to configure SoC before it starts the execution.
  361. Please refer doc/README.pblimage for more details
  362. CONFIG_SPL_FSL_PBL
  363. It adds a target to create boot binary having SPL binary in PBI format
  364. concatenated with u-boot binary.
  365. CONFIG_SYS_FSL_DDR_BE
  366. Defines the DDR controller register space as Big Endian
  367. CONFIG_SYS_FSL_DDR_LE
  368. Defines the DDR controller register space as Little Endian
  369. CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY
  370. Physical address from the view of DDR controllers. It is the
  371. same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But
  372. it could be different for ARM SoCs.
  373. CONFIG_SYS_FSL_DDR_INTLV_256B
  374. DDR controller interleaving on 256-byte. This is a special
  375. interleaving mode, handled by Dickens for Freescale layerscape
  376. SoCs with ARM core.
  377. CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS
  378. Number of controllers used as main memory.
  379. CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS
  380. Number of controllers used for other than main memory.
  381. CONFIG_SYS_FSL_HAS_DP_DDR
  382. Defines the SoC has DP-DDR used for DPAA.
  383. CONFIG_SYS_FSL_SEC_BE
  384. Defines the SEC controller register space as Big Endian
  385. CONFIG_SYS_FSL_SEC_LE
  386. Defines the SEC controller register space as Little Endian
  387. - MIPS CPU options:
  388. CONFIG_SYS_INIT_SP_OFFSET
  389. Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
  390. pointer. This is needed for the temporary stack before
  391. relocation.
  392. CONFIG_SYS_MIPS_CACHE_MODE
  393. Cache operation mode for the MIPS CPU.
  394. See also arch/mips/include/asm/mipsregs.h.
  395. Possible values are:
  396. CONF_CM_CACHABLE_NO_WA
  397. CONF_CM_CACHABLE_WA
  398. CONF_CM_UNCACHED
  399. CONF_CM_CACHABLE_NONCOHERENT
  400. CONF_CM_CACHABLE_CE
  401. CONF_CM_CACHABLE_COW
  402. CONF_CM_CACHABLE_CUW
  403. CONF_CM_CACHABLE_ACCELERATED
  404. CONFIG_SYS_XWAY_EBU_BOOTCFG
  405. Special option for Lantiq XWAY SoCs for booting from NOR flash.
  406. See also arch/mips/cpu/mips32/start.S.
  407. CONFIG_XWAY_SWAP_BYTES
  408. Enable compilation of tools/xway-swap-bytes needed for Lantiq
  409. XWAY SoCs for booting from NOR flash. The U-Boot image needs to
  410. be swapped if a flash programmer is used.
  411. - ARM options:
  412. CONFIG_SYS_EXCEPTION_VECTORS_HIGH
  413. Select high exception vectors of the ARM core, e.g., do not
  414. clear the V bit of the c1 register of CP15.
  415. COUNTER_FREQUENCY
  416. Generic timer clock source frequency.
  417. COUNTER_FREQUENCY_REAL
  418. Generic timer clock source frequency if the real clock is
  419. different from COUNTER_FREQUENCY, and can only be determined
  420. at run time.
  421. - Tegra SoC options:
  422. CONFIG_TEGRA_SUPPORT_NON_SECURE
  423. Support executing U-Boot in non-secure (NS) mode. Certain
  424. impossible actions will be skipped if the CPU is in NS mode,
  425. such as ARM architectural timer initialization.
  426. - Linux Kernel Interface:
  427. CONFIG_CLOCKS_IN_MHZ
  428. U-Boot stores all clock information in Hz
  429. internally. For binary compatibility with older Linux
  430. kernels (which expect the clocks passed in the
  431. bd_info data to be in MHz) the environment variable
  432. "clocks_in_mhz" can be defined so that U-Boot
  433. converts clock data to MHZ before passing it to the
  434. Linux kernel.
  435. When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
  436. "clocks_in_mhz=1" is automatically included in the
  437. default environment.
  438. CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
  439. When transferring memsize parameter to Linux, some versions
  440. expect it to be in bytes, others in MB.
  441. Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
  442. CONFIG_OF_LIBFDT
  443. New kernel versions are expecting firmware settings to be
  444. passed using flattened device trees (based on open firmware
  445. concepts).
  446. CONFIG_OF_LIBFDT
  447. * New libfdt-based support
  448. * Adds the "fdt" command
  449. * The bootm command automatically updates the fdt
  450. OF_TBCLK - The timebase frequency.
  451. OF_STDOUT_PATH - The path to the console device
  452. boards with QUICC Engines require OF_QE to set UCC MAC
  453. addresses
  454. CONFIG_OF_BOARD_SETUP
  455. Board code has addition modification that it wants to make
  456. to the flat device tree before handing it off to the kernel
  457. CONFIG_OF_SYSTEM_SETUP
  458. Other code has addition modification that it wants to make
  459. to the flat device tree before handing it off to the kernel.
  460. This causes ft_system_setup() to be called before booting
  461. the kernel.
  462. CONFIG_OF_IDE_FIXUP
  463. U-Boot can detect if an IDE device is present or not.
  464. If not, and this new config option is activated, U-Boot
  465. removes the ATA node from the DTS before booting Linux,
  466. so the Linux IDE driver does not probe the device and
  467. crash. This is needed for buggy hardware (uc101) where
  468. no pull down resistor is connected to the signal IDE5V_DD7.
  469. CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
  470. This setting is mandatory for all boards that have only one
  471. machine type and must be used to specify the machine type
  472. number as it appears in the ARM machine registry
  473. (see http://www.arm.linux.org.uk/developer/machines/).
  474. Only boards that have multiple machine types supported
  475. in a single configuration file and the machine type is
  476. runtime discoverable, do not have to use this setting.
  477. - vxWorks boot parameters:
  478. bootvx constructs a valid bootline using the following
  479. environments variables: bootdev, bootfile, ipaddr, netmask,
  480. serverip, gatewayip, hostname, othbootargs.
  481. It loads the vxWorks image pointed bootfile.
  482. Note: If a "bootargs" environment is defined, it will overwride
  483. the defaults discussed just above.
  484. - Cache Configuration:
  485. CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
  486. CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
  487. CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
  488. - Cache Configuration for ARM:
  489. CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
  490. controller
  491. CONFIG_SYS_PL310_BASE - Physical base address of PL310
  492. controller register space
  493. - Serial Ports:
  494. CONFIG_PL010_SERIAL
  495. Define this if you want support for Amba PrimeCell PL010 UARTs.
  496. CONFIG_PL011_SERIAL
  497. Define this if you want support for Amba PrimeCell PL011 UARTs.
  498. CONFIG_PL011_CLOCK
  499. If you have Amba PrimeCell PL011 UARTs, set this variable to
  500. the clock speed of the UARTs.
  501. CONFIG_PL01x_PORTS
  502. If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
  503. define this to a list of base addresses for each (supported)
  504. port. See e.g. include/configs/versatile.h
  505. CONFIG_SERIAL_HW_FLOW_CONTROL
  506. Define this variable to enable hw flow control in serial driver.
  507. Current user of this option is drivers/serial/nsl16550.c driver
  508. - Console Baudrate:
  509. CONFIG_BAUDRATE - in bps
  510. Select one of the baudrates listed in
  511. CONFIG_SYS_BAUDRATE_TABLE, see below.
  512. - Autoboot Command:
  513. CONFIG_BOOTCOMMAND
  514. Only needed when CONFIG_BOOTDELAY is enabled;
  515. define a command string that is automatically executed
  516. when no character is read on the console interface
  517. within "Boot Delay" after reset.
  518. CONFIG_BOOTARGS
  519. This can be used to pass arguments to the bootm
  520. command. The value of CONFIG_BOOTARGS goes into the
  521. environment value "bootargs".
  522. CONFIG_RAMBOOT and CONFIG_NFSBOOT
  523. The value of these goes into the environment as
  524. "ramboot" and "nfsboot" respectively, and can be used
  525. as a convenience, when switching between booting from
  526. RAM and NFS.
  527. - Bootcount:
  528. CONFIG_BOOTCOUNT_LIMIT
  529. Implements a mechanism for detecting a repeating reboot
  530. cycle, see:
  531. http://www.denx.de/wiki/view/DULG/UBootBootCountLimit
  532. CONFIG_BOOTCOUNT_ENV
  533. If no softreset save registers are found on the hardware
  534. "bootcount" is stored in the environment. To prevent a
  535. saveenv on all reboots, the environment variable
  536. "upgrade_available" is used. If "upgrade_available" is
  537. 0, "bootcount" is always 0, if "upgrade_available" is
  538. 1 "bootcount" is incremented in the environment.
  539. So the Userspace Applikation must set the "upgrade_available"
  540. and "bootcount" variable to 0, if a boot was successfully.
  541. - Pre-Boot Commands:
  542. CONFIG_PREBOOT
  543. When this option is #defined, the existence of the
  544. environment variable "preboot" will be checked
  545. immediately before starting the CONFIG_BOOTDELAY
  546. countdown and/or running the auto-boot command resp.
  547. entering interactive mode.
  548. This feature is especially useful when "preboot" is
  549. automatically generated or modified. For an example
  550. see the LWMON board specific code: here "preboot" is
  551. modified when the user holds down a certain
  552. combination of keys on the (special) keyboard when
  553. booting the systems
  554. - Serial Download Echo Mode:
  555. CONFIG_LOADS_ECHO
  556. If defined to 1, all characters received during a
  557. serial download (using the "loads" command) are
  558. echoed back. This might be needed by some terminal
  559. emulations (like "cu"), but may as well just take
  560. time on others. This setting #define's the initial
  561. value of the "loads_echo" environment variable.
  562. - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
  563. CONFIG_KGDB_BAUDRATE
  564. Select one of the baudrates listed in
  565. CONFIG_SYS_BAUDRATE_TABLE, see below.
  566. - Monitor Functions:
  567. Monitor commands can be included or excluded
  568. from the build by using the #include files
  569. <config_cmd_all.h> and #undef'ing unwanted
  570. commands, or adding #define's for wanted commands.
  571. The default command configuration includes all commands
  572. except those marked below with a "*".
  573. CONFIG_CMD_AES AES 128 CBC encrypt/decrypt
  574. CONFIG_CMD_ASKENV * ask for env variable
  575. CONFIG_CMD_BDI bdinfo
  576. CONFIG_CMD_BOOTD bootd
  577. CONFIG_CMD_BOOTI * ARM64 Linux kernel Image support
  578. CONFIG_CMD_CACHE * icache, dcache
  579. CONFIG_CMD_CONSOLE coninfo
  580. CONFIG_CMD_DHCP * DHCP support
  581. CONFIG_CMD_DIAG * Diagnostics
  582. CONFIG_CMD_ECHO echo arguments
  583. CONFIG_CMD_EDITENV edit env variable
  584. CONFIG_CMD_ELF * bootelf, bootvx
  585. CONFIG_CMD_ENV_EXISTS * check existence of env variable
  586. CONFIG_CMD_EXPORTENV * export the environment
  587. CONFIG_CMD_EXT2 * ext2 command support
  588. CONFIG_CMD_EXT4 * ext4 command support
  589. CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls)
  590. that work for multiple fs types
  591. CONFIG_CMD_FS_UUID * Look up a filesystem UUID
  592. CONFIG_CMD_SAVEENV saveenv
  593. CONFIG_CMD_FLASH flinfo, erase, protect
  594. CONFIG_CMD_FPGA FPGA device initialization support
  595. CONFIG_CMD_GO * the 'go' command (exec code)
  596. CONFIG_CMD_GREPENV * search environment
  597. CONFIG_CMD_I2C * I2C serial bus support
  598. CONFIG_CMD_IMI iminfo
  599. CONFIG_CMD_IMLS List all images found in NOR flash
  600. CONFIG_CMD_IMLS_NAND * List all images found in NAND flash
  601. CONFIG_CMD_IMPORTENV * import an environment
  602. CONFIG_CMD_INI * import data from an ini file into the env
  603. CONFIG_CMD_ITEST Integer/string test of 2 values
  604. CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader)
  605. CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration
  606. (169.254.*.*)
  607. CONFIG_CMD_LOADB loadb
  608. CONFIG_CMD_LOADS loads
  609. CONFIG_CMD_MD5SUM * print md5 message digest
  610. (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
  611. CONFIG_CMD_MEMINFO * Display detailed memory information
  612. CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
  613. loop, loopw
  614. CONFIG_CMD_MEMTEST * mtest
  615. CONFIG_CMD_MISC Misc functions like sleep etc
  616. CONFIG_CMD_MMC * MMC memory mapped support
  617. CONFIG_CMD_MII * MII utility commands
  618. CONFIG_CMD_MTDPARTS * MTD partition support
  619. CONFIG_CMD_NAND * NAND support
  620. CONFIG_CMD_NET bootp, tftpboot, rarpboot
  621. CONFIG_CMD_NFS NFS support
  622. CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
  623. CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
  624. CONFIG_CMD_PCI * pciinfo
  625. CONFIG_CMD_PCMCIA * PCMCIA support
  626. CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
  627. host
  628. CONFIG_CMD_PORTIO * Port I/O
  629. CONFIG_CMD_READ * Read raw data from partition
  630. CONFIG_CMD_REGINFO * Register dump
  631. CONFIG_CMD_RUN run command in env variable
  632. CONFIG_CMD_SANDBOX * sb command to access sandbox features
  633. CONFIG_CMD_SAVES * save S record dump
  634. CONFIG_SCSI * SCSI Support
  635. CONFIG_CMD_SDRAM * print SDRAM configuration information
  636. (requires CONFIG_CMD_I2C)
  637. CONFIG_CMD_SF * Read/write/erase SPI NOR flash
  638. CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x
  639. CONFIG_CMD_SOURCE "source" command Support
  640. CONFIG_CMD_SPI * SPI serial bus support
  641. CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
  642. CONFIG_CMD_TFTPPUT * TFTP put command (upload)
  643. CONFIG_CMD_TIME * run command and report execution time (ARM specific)
  644. CONFIG_CMD_TIMER * access to the system tick timer
  645. CONFIG_CMD_USB * USB support
  646. CONFIG_CMD_CDP * Cisco Discover Protocol support
  647. CONFIG_CMD_MFSL * Microblaze FSL support
  648. CONFIG_CMD_XIMG Load part of Multi Image
  649. CONFIG_CMD_UUID * Generate random UUID or GUID string
  650. EXAMPLE: If you want all functions except of network
  651. support you can write:
  652. #include "config_cmd_all.h"
  653. #undef CONFIG_CMD_NET
  654. Other Commands:
  655. fdt (flattened device tree) command: CONFIG_OF_LIBFDT
  656. Note: Don't enable the "icache" and "dcache" commands
  657. (configuration option CONFIG_CMD_CACHE) unless you know
  658. what you (and your U-Boot users) are doing. Data
  659. cache cannot be enabled on systems like the
  660. 8260 (where accesses to the IMMR region must be
  661. uncached), and it cannot be disabled on all other
  662. systems where we (mis-) use the data cache to hold an
  663. initial stack and some data.
  664. XXX - this list needs to get updated!
  665. - Removal of commands
  666. If no commands are needed to boot, you can disable
  667. CONFIG_CMDLINE to remove them. In this case, the command line
  668. will not be available, and when U-Boot wants to execute the
  669. boot command (on start-up) it will call board_run_command()
  670. instead. This can reduce image size significantly for very
  671. simple boot procedures.
  672. - Regular expression support:
  673. CONFIG_REGEX
  674. If this variable is defined, U-Boot is linked against
  675. the SLRE (Super Light Regular Expression) library,
  676. which adds regex support to some commands, as for
  677. example "env grep" and "setexpr".
  678. - Device tree:
  679. CONFIG_OF_CONTROL
  680. If this variable is defined, U-Boot will use a device tree
  681. to configure its devices, instead of relying on statically
  682. compiled #defines in the board file. This option is
  683. experimental and only available on a few boards. The device
  684. tree is available in the global data as gd->fdt_blob.
  685. U-Boot needs to get its device tree from somewhere. This can
  686. be done using one of the three options below:
  687. CONFIG_OF_EMBED
  688. If this variable is defined, U-Boot will embed a device tree
  689. binary in its image. This device tree file should be in the
  690. board directory and called <soc>-<board>.dts. The binary file
  691. is then picked up in board_init_f() and made available through
  692. the global data structure as gd->blob.
  693. CONFIG_OF_SEPARATE
  694. If this variable is defined, U-Boot will build a device tree
  695. binary. It will be called u-boot.dtb. Architecture-specific
  696. code will locate it at run-time. Generally this works by:
  697. cat u-boot.bin u-boot.dtb >image.bin
  698. and in fact, U-Boot does this for you, creating a file called
  699. u-boot-dtb.bin which is useful in the common case. You can
  700. still use the individual files if you need something more
  701. exotic.
  702. CONFIG_OF_BOARD
  703. If this variable is defined, U-Boot will use the device tree
  704. provided by the board at runtime instead of embedding one with
  705. the image. Only boards defining board_fdt_blob_setup() support
  706. this option (see include/fdtdec.h file).
  707. - Watchdog:
  708. CONFIG_WATCHDOG
  709. If this variable is defined, it enables watchdog
  710. support for the SoC. There must be support in the SoC
  711. specific code for a watchdog. When supported for a
  712. specific SoC is available, then no further board specific
  713. code should be needed to use it.
  714. CONFIG_HW_WATCHDOG
  715. When using a watchdog circuitry external to the used
  716. SoC, then define this variable and provide board
  717. specific code for the "hw_watchdog_reset" function.
  718. CONFIG_AT91_HW_WDT_TIMEOUT
  719. specify the timeout in seconds. default 2 seconds.
  720. - U-Boot Version:
  721. CONFIG_VERSION_VARIABLE
  722. If this variable is defined, an environment variable
  723. named "ver" is created by U-Boot showing the U-Boot
  724. version as printed by the "version" command.
  725. Any change to this variable will be reverted at the
  726. next reset.
  727. - Real-Time Clock:
  728. When CONFIG_CMD_DATE is selected, the type of the RTC
  729. has to be selected, too. Define exactly one of the
  730. following options:
  731. CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
  732. CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
  733. CONFIG_RTC_MC146818 - use MC146818 RTC
  734. CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
  735. CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
  736. CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
  737. CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC
  738. CONFIG_RTC_DS164x - use Dallas DS164x RTC
  739. CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
  740. CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
  741. CONFIG_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
  742. CONFIG_SYS_RV3029_TCR - enable trickle charger on
  743. RV3029 RTC.
  744. Note that if the RTC uses I2C, then the I2C interface
  745. must also be configured. See I2C Support, below.
  746. - GPIO Support:
  747. CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
  748. The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
  749. chip-ngpio pairs that tell the PCA953X driver the number of
  750. pins supported by a particular chip.
  751. Note that if the GPIO device uses I2C, then the I2C interface
  752. must also be configured. See I2C Support, below.
  753. - I/O tracing:
  754. When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O
  755. accesses and can checksum them or write a list of them out
  756. to memory. See the 'iotrace' command for details. This is
  757. useful for testing device drivers since it can confirm that
  758. the driver behaves the same way before and after a code
  759. change. Currently this is supported on sandbox and arm. To
  760. add support for your architecture, add '#include <iotrace.h>'
  761. to the bottom of arch/<arch>/include/asm/io.h and test.
  762. Example output from the 'iotrace stats' command is below.
  763. Note that if the trace buffer is exhausted, the checksum will
  764. still continue to operate.
  765. iotrace is enabled
  766. Start: 10000000 (buffer start address)
  767. Size: 00010000 (buffer size)
  768. Offset: 00000120 (current buffer offset)
  769. Output: 10000120 (start + offset)
  770. Count: 00000018 (number of trace records)
  771. CRC32: 9526fb66 (CRC32 of all trace records)
  772. - Timestamp Support:
  773. When CONFIG_TIMESTAMP is selected, the timestamp
  774. (date and time) of an image is printed by image
  775. commands like bootm or iminfo. This option is
  776. automatically enabled when you select CONFIG_CMD_DATE .
  777. - Partition Labels (disklabels) Supported:
  778. Zero or more of the following:
  779. CONFIG_MAC_PARTITION Apple's MacOS partition table.
  780. CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
  781. CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
  782. bootloader. Note 2TB partition limit; see
  783. disk/part_efi.c
  784. CONFIG_MTD_PARTITIONS Memory Technology Device partition table.
  785. If IDE or SCSI support is enabled (CONFIG_IDE or
  786. CONFIG_SCSI) you must configure support for at
  787. least one non-MTD partition type as well.
  788. - IDE Reset method:
  789. CONFIG_IDE_RESET_ROUTINE - this is defined in several
  790. board configurations files but used nowhere!
  791. CONFIG_IDE_RESET - is this is defined, IDE Reset will
  792. be performed by calling the function
  793. ide_set_reset(int reset)
  794. which has to be defined in a board specific file
  795. - ATAPI Support:
  796. CONFIG_ATAPI
  797. Set this to enable ATAPI support.
  798. - LBA48 Support
  799. CONFIG_LBA48
  800. Set this to enable support for disks larger than 137GB
  801. Also look at CONFIG_SYS_64BIT_LBA.
  802. Whithout these , LBA48 support uses 32bit variables and will 'only'
  803. support disks up to 2.1TB.
  804. CONFIG_SYS_64BIT_LBA:
  805. When enabled, makes the IDE subsystem use 64bit sector addresses.
  806. Default is 32bit.
  807. - SCSI Support:
  808. At the moment only there is only support for the
  809. SYM53C8XX SCSI controller; define
  810. CONFIG_SCSI_SYM53C8XX to enable it.
  811. CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
  812. CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
  813. CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
  814. maximum numbers of LUNs, SCSI ID's and target
  815. devices.
  816. CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
  817. The environment variable 'scsidevs' is set to the number of
  818. SCSI devices found during the last scan.
  819. - NETWORK Support (PCI):
  820. CONFIG_E1000
  821. Support for Intel 8254x/8257x gigabit chips.
  822. CONFIG_E1000_SPI
  823. Utility code for direct access to the SPI bus on Intel 8257x.
  824. This does not do anything useful unless you set at least one
  825. of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
  826. CONFIG_E1000_SPI_GENERIC
  827. Allow generic access to the SPI bus on the Intel 8257x, for
  828. example with the "sspi" command.
  829. CONFIG_CMD_E1000
  830. Management command for E1000 devices. When used on devices
  831. with SPI support you can reprogram the EEPROM from U-Boot.
  832. CONFIG_EEPRO100
  833. Support for Intel 82557/82559/82559ER chips.
  834. Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
  835. write routine for first time initialisation.
  836. CONFIG_TULIP
  837. Support for Digital 2114x chips.
  838. Optional CONFIG_TULIP_SELECT_MEDIA for board specific
  839. modem chip initialisation (KS8761/QS6611).
  840. CONFIG_NATSEMI
  841. Support for National dp83815 chips.
  842. CONFIG_NS8382X
  843. Support for National dp8382[01] gigabit chips.
  844. - NETWORK Support (other):
  845. CONFIG_DRIVER_AT91EMAC
  846. Support for AT91RM9200 EMAC.
  847. CONFIG_RMII
  848. Define this to use reduced MII inteface
  849. CONFIG_DRIVER_AT91EMAC_QUIET
  850. If this defined, the driver is quiet.
  851. The driver doen't show link status messages.
  852. CONFIG_CALXEDA_XGMAC
  853. Support for the Calxeda XGMAC device
  854. CONFIG_LAN91C96
  855. Support for SMSC's LAN91C96 chips.
  856. CONFIG_LAN91C96_USE_32_BIT
  857. Define this to enable 32 bit addressing
  858. CONFIG_SMC91111
  859. Support for SMSC's LAN91C111 chip
  860. CONFIG_SMC91111_BASE
  861. Define this to hold the physical address
  862. of the device (I/O space)
  863. CONFIG_SMC_USE_32_BIT
  864. Define this if data bus is 32 bits
  865. CONFIG_SMC_USE_IOFUNCS
  866. Define this to use i/o functions instead of macros
  867. (some hardware wont work with macros)
  868. CONFIG_DRIVER_TI_EMAC
  869. Support for davinci emac
  870. CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
  871. Define this if you have more then 3 PHYs.
  872. CONFIG_FTGMAC100
  873. Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
  874. CONFIG_FTGMAC100_EGIGA
  875. Define this to use GE link update with gigabit PHY.
  876. Define this if FTGMAC100 is connected to gigabit PHY.
  877. If your system has 10/100 PHY only, it might not occur
  878. wrong behavior. Because PHY usually return timeout or
  879. useless data when polling gigabit status and gigabit
  880. control registers. This behavior won't affect the
  881. correctnessof 10/100 link speed update.
  882. CONFIG_SMC911X
  883. Support for SMSC's LAN911x and LAN921x chips
  884. CONFIG_SMC911X_BASE
  885. Define this to hold the physical address
  886. of the device (I/O space)
  887. CONFIG_SMC911X_32_BIT
  888. Define this if data bus is 32 bits
  889. CONFIG_SMC911X_16_BIT
  890. Define this if data bus is 16 bits. If your processor
  891. automatically converts one 32 bit word to two 16 bit
  892. words you may also try CONFIG_SMC911X_32_BIT.
  893. CONFIG_SH_ETHER
  894. Support for Renesas on-chip Ethernet controller
  895. CONFIG_SH_ETHER_USE_PORT
  896. Define the number of ports to be used
  897. CONFIG_SH_ETHER_PHY_ADDR
  898. Define the ETH PHY's address
  899. CONFIG_SH_ETHER_CACHE_WRITEBACK
  900. If this option is set, the driver enables cache flush.
  901. - PWM Support:
  902. CONFIG_PWM_IMX
  903. Support for PWM module on the imx6.
  904. - TPM Support:
  905. CONFIG_TPM
  906. Support TPM devices.
  907. CONFIG_TPM_TIS_INFINEON
  908. Support for Infineon i2c bus TPM devices. Only one device
  909. per system is supported at this time.
  910. CONFIG_TPM_TIS_I2C_BURST_LIMITATION
  911. Define the burst count bytes upper limit
  912. CONFIG_TPM_ST33ZP24
  913. Support for STMicroelectronics TPM devices. Requires DM_TPM support.
  914. CONFIG_TPM_ST33ZP24_I2C
  915. Support for STMicroelectronics ST33ZP24 I2C devices.
  916. Requires TPM_ST33ZP24 and I2C.
  917. CONFIG_TPM_ST33ZP24_SPI
  918. Support for STMicroelectronics ST33ZP24 SPI devices.
  919. Requires TPM_ST33ZP24 and SPI.
  920. CONFIG_TPM_ATMEL_TWI
  921. Support for Atmel TWI TPM device. Requires I2C support.
  922. CONFIG_TPM_TIS_LPC
  923. Support for generic parallel port TPM devices. Only one device
  924. per system is supported at this time.
  925. CONFIG_TPM_TIS_BASE_ADDRESS
  926. Base address where the generic TPM device is mapped
  927. to. Contemporary x86 systems usually map it at
  928. 0xfed40000.
  929. CONFIG_CMD_TPM
  930. Add tpm monitor functions.
  931. Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also
  932. provides monitor access to authorized functions.
  933. CONFIG_TPM
  934. Define this to enable the TPM support library which provides
  935. functional interfaces to some TPM commands.
  936. Requires support for a TPM device.
  937. CONFIG_TPM_AUTH_SESSIONS
  938. Define this to enable authorized functions in the TPM library.
  939. Requires CONFIG_TPM and CONFIG_SHA1.
  940. - USB Support:
  941. At the moment only the UHCI host controller is
  942. supported (PIP405, MIP405); define
  943. CONFIG_USB_UHCI to enable it.
  944. define CONFIG_USB_KEYBOARD to enable the USB Keyboard
  945. and define CONFIG_USB_STORAGE to enable the USB
  946. storage devices.
  947. Note:
  948. Supported are USB Keyboards and USB Floppy drives
  949. (TEAC FD-05PUB).
  950. CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
  951. txfilltuning field in the EHCI controller on reset.
  952. CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2
  953. HW module registers.
  954. - USB Device:
  955. Define the below if you wish to use the USB console.
  956. Once firmware is rebuilt from a serial console issue the
  957. command "setenv stdin usbtty; setenv stdout usbtty" and
  958. attach your USB cable. The Unix command "dmesg" should print
  959. it has found a new device. The environment variable usbtty
  960. can be set to gserial or cdc_acm to enable your device to
  961. appear to a USB host as a Linux gserial device or a
  962. Common Device Class Abstract Control Model serial device.
  963. If you select usbtty = gserial you should be able to enumerate
  964. a Linux host by
  965. # modprobe usbserial vendor=0xVendorID product=0xProductID
  966. else if using cdc_acm, simply setting the environment
  967. variable usbtty to be cdc_acm should suffice. The following
  968. might be defined in YourBoardName.h
  969. CONFIG_USB_DEVICE
  970. Define this to build a UDC device
  971. CONFIG_USB_TTY
  972. Define this to have a tty type of device available to
  973. talk to the UDC device
  974. CONFIG_USBD_HS
  975. Define this to enable the high speed support for usb
  976. device and usbtty. If this feature is enabled, a routine
  977. int is_usbd_high_speed(void)
  978. also needs to be defined by the driver to dynamically poll
  979. whether the enumeration has succeded at high speed or full
  980. speed.
  981. CONFIG_SYS_CONSOLE_IS_IN_ENV
  982. Define this if you want stdin, stdout &/or stderr to
  983. be set to usbtty.
  984. If you have a USB-IF assigned VendorID then you may wish to
  985. define your own vendor specific values either in BoardName.h
  986. or directly in usbd_vendor_info.h. If you don't define
  987. CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
  988. CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
  989. should pretend to be a Linux device to it's target host.
  990. CONFIG_USBD_MANUFACTURER
  991. Define this string as the name of your company for
  992. - CONFIG_USBD_MANUFACTURER "my company"
  993. CONFIG_USBD_PRODUCT_NAME
  994. Define this string as the name of your product
  995. - CONFIG_USBD_PRODUCT_NAME "acme usb device"
  996. CONFIG_USBD_VENDORID
  997. Define this as your assigned Vendor ID from the USB
  998. Implementors Forum. This *must* be a genuine Vendor ID
  999. to avoid polluting the USB namespace.
  1000. - CONFIG_USBD_VENDORID 0xFFFF
  1001. CONFIG_USBD_PRODUCTID
  1002. Define this as the unique Product ID
  1003. for your device
  1004. - CONFIG_USBD_PRODUCTID 0xFFFF
  1005. - ULPI Layer Support:
  1006. The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
  1007. the generic ULPI layer. The generic layer accesses the ULPI PHY
  1008. via the platform viewport, so you need both the genric layer and
  1009. the viewport enabled. Currently only Chipidea/ARC based
  1010. viewport is supported.
  1011. To enable the ULPI layer support, define CONFIG_USB_ULPI and
  1012. CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
  1013. If your ULPI phy needs a different reference clock than the
  1014. standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
  1015. the appropriate value in Hz.
  1016. - MMC Support:
  1017. The MMC controller on the Intel PXA is supported. To
  1018. enable this define CONFIG_MMC. The MMC can be
  1019. accessed from the boot prompt by mapping the device
  1020. to physical memory similar to flash. Command line is
  1021. enabled with CONFIG_CMD_MMC. The MMC driver also works with
  1022. the FAT fs. This is enabled with CONFIG_CMD_FAT.
  1023. CONFIG_SH_MMCIF
  1024. Support for Renesas on-chip MMCIF controller
  1025. CONFIG_SH_MMCIF_ADDR
  1026. Define the base address of MMCIF registers
  1027. CONFIG_SH_MMCIF_CLK
  1028. Define the clock frequency for MMCIF
  1029. CONFIG_SUPPORT_EMMC_BOOT
  1030. Enable some additional features of the eMMC boot partitions.
  1031. CONFIG_SUPPORT_EMMC_RPMB
  1032. Enable the commands for reading, writing and programming the
  1033. key for the Replay Protection Memory Block partition in eMMC.
  1034. - USB Device Firmware Update (DFU) class support:
  1035. CONFIG_USB_FUNCTION_DFU
  1036. This enables the USB portion of the DFU USB class
  1037. CONFIG_CMD_DFU
  1038. This enables the command "dfu" which is used to have
  1039. U-Boot create a DFU class device via USB. This command
  1040. requires that the "dfu_alt_info" environment variable be
  1041. set and define the alt settings to expose to the host.
  1042. CONFIG_DFU_MMC
  1043. This enables support for exposing (e)MMC devices via DFU.
  1044. CONFIG_DFU_NAND
  1045. This enables support for exposing NAND devices via DFU.
  1046. CONFIG_DFU_RAM
  1047. This enables support for exposing RAM via DFU.
  1048. Note: DFU spec refer to non-volatile memory usage, but
  1049. allow usages beyond the scope of spec - here RAM usage,
  1050. one that would help mostly the developer.
  1051. CONFIG_SYS_DFU_DATA_BUF_SIZE
  1052. Dfu transfer uses a buffer before writing data to the
  1053. raw storage device. Make the size (in bytes) of this buffer
  1054. configurable. The size of this buffer is also configurable
  1055. through the "dfu_bufsiz" environment variable.
  1056. CONFIG_SYS_DFU_MAX_FILE_SIZE
  1057. When updating files rather than the raw storage device,
  1058. we use a static buffer to copy the file into and then write
  1059. the buffer once we've been given the whole file. Define
  1060. this to the maximum filesize (in bytes) for the buffer.
  1061. Default is 4 MiB if undefined.
  1062. DFU_DEFAULT_POLL_TIMEOUT
  1063. Poll timeout [ms], is the timeout a device can send to the
  1064. host. The host must wait for this timeout before sending
  1065. a subsequent DFU_GET_STATUS request to the device.
  1066. DFU_MANIFEST_POLL_TIMEOUT
  1067. Poll timeout [ms], which the device sends to the host when
  1068. entering dfuMANIFEST state. Host waits this timeout, before
  1069. sending again an USB request to the device.
  1070. - USB Device Android Fastboot support:
  1071. CONFIG_USB_FUNCTION_FASTBOOT
  1072. This enables the USB part of the fastboot gadget
  1073. CONFIG_CMD_FASTBOOT
  1074. This enables the command "fastboot" which enables the Android
  1075. fastboot mode for the platform's USB device. Fastboot is a USB
  1076. protocol for downloading images, flashing and device control
  1077. used on Android devices.
  1078. See doc/README.android-fastboot for more information.
  1079. CONFIG_ANDROID_BOOT_IMAGE
  1080. This enables support for booting images which use the Android
  1081. image format header.
  1082. CONFIG_FASTBOOT_BUF_ADDR
  1083. The fastboot protocol requires a large memory buffer for
  1084. downloads. Define this to the starting RAM address to use for
  1085. downloaded images.
  1086. CONFIG_FASTBOOT_BUF_SIZE
  1087. The fastboot protocol requires a large memory buffer for
  1088. downloads. This buffer should be as large as possible for a
  1089. platform. Define this to the size available RAM for fastboot.
  1090. CONFIG_FASTBOOT_FLASH
  1091. The fastboot protocol includes a "flash" command for writing
  1092. the downloaded image to a non-volatile storage device. Define
  1093. this to enable the "fastboot flash" command.
  1094. CONFIG_FASTBOOT_FLASH_MMC_DEV
  1095. The fastboot "flash" command requires additional information
  1096. regarding the non-volatile storage device. Define this to
  1097. the eMMC device that fastboot should use to store the image.
  1098. CONFIG_FASTBOOT_GPT_NAME
  1099. The fastboot "flash" command supports writing the downloaded
  1100. image to the Protective MBR and the Primary GUID Partition
  1101. Table. (Additionally, this downloaded image is post-processed
  1102. to generate and write the Backup GUID Partition Table.)
  1103. This occurs when the specified "partition name" on the
  1104. "fastboot flash" command line matches this value.
  1105. The default is "gpt" if undefined.
  1106. CONFIG_FASTBOOT_MBR_NAME
  1107. The fastboot "flash" command supports writing the downloaded
  1108. image to DOS MBR.
  1109. This occurs when the "partition name" specified on the
  1110. "fastboot flash" command line matches this value.
  1111. If not defined the default value "mbr" is used.
  1112. - Journaling Flash filesystem support:
  1113. CONFIG_JFFS2_NAND
  1114. Define these for a default partition on a NAND device
  1115. CONFIG_SYS_JFFS2_FIRST_SECTOR,
  1116. CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
  1117. Define these for a default partition on a NOR device
  1118. - Keyboard Support:
  1119. See Kconfig help for available keyboard drivers.
  1120. CONFIG_KEYBOARD
  1121. Define this to enable a custom keyboard support.
  1122. This simply calls drv_keyboard_init() which must be
  1123. defined in your board-specific files. This option is deprecated
  1124. and is only used by novena. For new boards, use driver model
  1125. instead.
  1126. - Video support:
  1127. CONFIG_FSL_DIU_FB
  1128. Enable the Freescale DIU video driver. Reference boards for
  1129. SOCs that have a DIU should define this macro to enable DIU
  1130. support, and should also define these other macros:
  1131. CONFIG_SYS_DIU_ADDR
  1132. CONFIG_VIDEO
  1133. CONFIG_CFB_CONSOLE
  1134. CONFIG_VIDEO_SW_CURSOR
  1135. CONFIG_VGA_AS_SINGLE_DEVICE
  1136. CONFIG_VIDEO_LOGO
  1137. CONFIG_VIDEO_BMP_LOGO
  1138. The DIU driver will look for the 'video-mode' environment
  1139. variable, and if defined, enable the DIU as a console during
  1140. boot. See the documentation file doc/README.video for a
  1141. description of this variable.
  1142. - LCD Support: CONFIG_LCD
  1143. Define this to enable LCD support (for output to LCD
  1144. display); also select one of the supported displays
  1145. by defining one of these:
  1146. CONFIG_ATMEL_LCD:
  1147. HITACHI TX09D70VM1CCA, 3.5", 240x320.
  1148. CONFIG_NEC_NL6448AC33:
  1149. NEC NL6448AC33-18. Active, color, single scan.
  1150. CONFIG_NEC_NL6448BC20
  1151. NEC NL6448BC20-08. 6.5", 640x480.
  1152. Active, color, single scan.
  1153. CONFIG_NEC_NL6448BC33_54
  1154. NEC NL6448BC33-54. 10.4", 640x480.
  1155. Active, color, single scan.
  1156. CONFIG_SHARP_16x9
  1157. Sharp 320x240. Active, color, single scan.
  1158. It isn't 16x9, and I am not sure what it is.
  1159. CONFIG_SHARP_LQ64D341
  1160. Sharp LQ64D341 display, 640x480.
  1161. Active, color, single scan.
  1162. CONFIG_HLD1045
  1163. HLD1045 display, 640x480.
  1164. Active, color, single scan.
  1165. CONFIG_OPTREX_BW
  1166. Optrex CBL50840-2 NF-FW 99 22 M5
  1167. or
  1168. Hitachi LMG6912RPFC-00T
  1169. or
  1170. Hitachi SP14Q002
  1171. 320x240. Black & white.
  1172. CONFIG_LCD_ALIGNMENT
  1173. Normally the LCD is page-aligned (typically 4KB). If this is
  1174. defined then the LCD will be aligned to this value instead.
  1175. For ARM it is sometimes useful to use MMU_SECTION_SIZE
  1176. here, since it is cheaper to change data cache settings on
  1177. a per-section basis.
  1178. CONFIG_LCD_ROTATION
  1179. Sometimes, for example if the display is mounted in portrait
  1180. mode or even if it's mounted landscape but rotated by 180degree,
  1181. we need to rotate our content of the display relative to the
  1182. framebuffer, so that user can read the messages which are
  1183. printed out.
  1184. Once CONFIG_LCD_ROTATION is defined, the lcd_console will be
  1185. initialized with a given rotation from "vl_rot" out of
  1186. "vidinfo_t" which is provided by the board specific code.
  1187. The value for vl_rot is coded as following (matching to
  1188. fbcon=rotate:<n> linux-kernel commandline):
  1189. 0 = no rotation respectively 0 degree
  1190. 1 = 90 degree rotation
  1191. 2 = 180 degree rotation
  1192. 3 = 270 degree rotation
  1193. If CONFIG_LCD_ROTATION is not defined, the console will be
  1194. initialized with 0degree rotation.
  1195. CONFIG_LCD_BMP_RLE8
  1196. Support drawing of RLE8-compressed bitmaps on the LCD.
  1197. CONFIG_I2C_EDID
  1198. Enables an 'i2c edid' command which can read EDID
  1199. information over I2C from an attached LCD display.
  1200. - Splash Screen Support: CONFIG_SPLASH_SCREEN
  1201. If this option is set, the environment is checked for
  1202. a variable "splashimage". If found, the usual display
  1203. of logo, copyright and system information on the LCD
  1204. is suppressed and the BMP image at the address
  1205. specified in "splashimage" is loaded instead. The
  1206. console is redirected to the "nulldev", too. This
  1207. allows for a "silent" boot where a splash screen is
  1208. loaded very quickly after power-on.
  1209. CONFIG_SPLASHIMAGE_GUARD
  1210. If this option is set, then U-Boot will prevent the environment
  1211. variable "splashimage" from being set to a problematic address
  1212. (see doc/README.displaying-bmps).
  1213. This option is useful for targets where, due to alignment
  1214. restrictions, an improperly aligned BMP image will cause a data
  1215. abort. If you think you will not have problems with unaligned
  1216. accesses (for example because your toolchain prevents them)
  1217. there is no need to set this option.
  1218. CONFIG_SPLASH_SCREEN_ALIGN
  1219. If this option is set the splash image can be freely positioned
  1220. on the screen. Environment variable "splashpos" specifies the
  1221. position as "x,y". If a positive number is given it is used as
  1222. number of pixel from left/top. If a negative number is given it
  1223. is used as number of pixel from right/bottom. You can also
  1224. specify 'm' for centering the image.
  1225. Example:
  1226. setenv splashpos m,m
  1227. => image at center of screen
  1228. setenv splashpos 30,20
  1229. => image at x = 30 and y = 20
  1230. setenv splashpos -10,m
  1231. => vertically centered image
  1232. at x = dspWidth - bmpWidth - 9
  1233. - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
  1234. If this option is set, additionally to standard BMP
  1235. images, gzipped BMP images can be displayed via the
  1236. splashscreen support or the bmp command.
  1237. - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
  1238. If this option is set, 8-bit RLE compressed BMP images
  1239. can be displayed via the splashscreen support or the
  1240. bmp command.
  1241. - Compression support:
  1242. CONFIG_GZIP
  1243. Enabled by default to support gzip compressed images.
  1244. CONFIG_BZIP2
  1245. If this option is set, support for bzip2 compressed
  1246. images is included. If not, only uncompressed and gzip
  1247. compressed images are supported.
  1248. NOTE: the bzip2 algorithm requires a lot of RAM, so
  1249. the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
  1250. be at least 4MB.
  1251. CONFIG_LZO
  1252. If this option is set, support for LZO compressed images
  1253. is included.
  1254. - MII/PHY support:
  1255. CONFIG_PHY_ADDR
  1256. The address of PHY on MII bus.
  1257. CONFIG_PHY_CLOCK_FREQ (ppc4xx)
  1258. The clock frequency of the MII bus
  1259. CONFIG_PHY_GIGE
  1260. If this option is set, support for speed/duplex
  1261. detection of gigabit PHY is included.
  1262. CONFIG_PHY_RESET_DELAY
  1263. Some PHY like Intel LXT971A need extra delay after
  1264. reset before any MII register access is possible.
  1265. For such PHY, set this option to the usec delay
  1266. required. (minimum 300usec for LXT971A)
  1267. CONFIG_PHY_CMD_DELAY (ppc4xx)
  1268. Some PHY like Intel LXT971A need extra delay after
  1269. command issued before MII status register can be read
  1270. - IP address:
  1271. CONFIG_IPADDR
  1272. Define a default value for the IP address to use for
  1273. the default Ethernet interface, in case this is not
  1274. determined through e.g. bootp.
  1275. (Environment variable "ipaddr")
  1276. - Server IP address:
  1277. CONFIG_SERVERIP
  1278. Defines a default value for the IP address of a TFTP
  1279. server to contact when using the "tftboot" command.
  1280. (Environment variable "serverip")
  1281. CONFIG_KEEP_SERVERADDR
  1282. Keeps the server's MAC address, in the env 'serveraddr'
  1283. for passing to bootargs (like Linux's netconsole option)
  1284. - Gateway IP address:
  1285. CONFIG_GATEWAYIP
  1286. Defines a default value for the IP address of the
  1287. default router where packets to other networks are
  1288. sent to.
  1289. (Environment variable "gatewayip")
  1290. - Subnet mask:
  1291. CONFIG_NETMASK
  1292. Defines a default value for the subnet mask (or
  1293. routing prefix) which is used to determine if an IP
  1294. address belongs to the local subnet or needs to be
  1295. forwarded through a router.
  1296. (Environment variable "netmask")
  1297. - Multicast TFTP Mode:
  1298. CONFIG_MCAST_TFTP
  1299. Defines whether you want to support multicast TFTP as per
  1300. rfc-2090; for example to work with atftp. Lets lots of targets
  1301. tftp down the same boot image concurrently. Note: the Ethernet
  1302. driver in use must provide a function: mcast() to join/leave a
  1303. multicast group.
  1304. - BOOTP Recovery Mode:
  1305. CONFIG_BOOTP_RANDOM_DELAY
  1306. If you have many targets in a network that try to
  1307. boot using BOOTP, you may want to avoid that all
  1308. systems send out BOOTP requests at precisely the same
  1309. moment (which would happen for instance at recovery
  1310. from a power failure, when all systems will try to
  1311. boot, thus flooding the BOOTP server. Defining
  1312. CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
  1313. inserted before sending out BOOTP requests. The
  1314. following delays are inserted then:
  1315. 1st BOOTP request: delay 0 ... 1 sec
  1316. 2nd BOOTP request: delay 0 ... 2 sec
  1317. 3rd BOOTP request: delay 0 ... 4 sec
  1318. 4th and following
  1319. BOOTP requests: delay 0 ... 8 sec
  1320. CONFIG_BOOTP_ID_CACHE_SIZE
  1321. BOOTP packets are uniquely identified using a 32-bit ID. The
  1322. server will copy the ID from client requests to responses and
  1323. U-Boot will use this to determine if it is the destination of
  1324. an incoming response. Some servers will check that addresses
  1325. aren't in use before handing them out (usually using an ARP
  1326. ping) and therefore take up to a few hundred milliseconds to
  1327. respond. Network congestion may also influence the time it
  1328. takes for a response to make it back to the client. If that
  1329. time is too long, U-Boot will retransmit requests. In order
  1330. to allow earlier responses to still be accepted after these
  1331. retransmissions, U-Boot's BOOTP client keeps a small cache of
  1332. IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this
  1333. cache. The default is to keep IDs for up to four outstanding
  1334. requests. Increasing this will allow U-Boot to accept offers
  1335. from a BOOTP client in networks with unusually high latency.
  1336. - DHCP Advanced Options:
  1337. You can fine tune the DHCP functionality by defining
  1338. CONFIG_BOOTP_* symbols:
  1339. CONFIG_BOOTP_SUBNETMASK
  1340. CONFIG_BOOTP_GATEWAY
  1341. CONFIG_BOOTP_HOSTNAME
  1342. CONFIG_BOOTP_NISDOMAIN
  1343. CONFIG_BOOTP_BOOTPATH
  1344. CONFIG_BOOTP_BOOTFILESIZE
  1345. CONFIG_BOOTP_DNS
  1346. CONFIG_BOOTP_DNS2
  1347. CONFIG_BOOTP_SEND_HOSTNAME
  1348. CONFIG_BOOTP_NTPSERVER
  1349. CONFIG_BOOTP_TIMEOFFSET
  1350. CONFIG_BOOTP_VENDOREX
  1351. CONFIG_BOOTP_MAY_FAIL
  1352. CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
  1353. environment variable, not the BOOTP server.
  1354. CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
  1355. after the configured retry count, the call will fail
  1356. instead of starting over. This can be used to fail over
  1357. to Link-local IP address configuration if the DHCP server
  1358. is not available.
  1359. CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
  1360. serverip from a DHCP server, it is possible that more
  1361. than one DNS serverip is offered to the client.
  1362. If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
  1363. serverip will be stored in the additional environment
  1364. variable "dnsip2". The first DNS serverip is always
  1365. stored in the variable "dnsip", when CONFIG_BOOTP_DNS
  1366. is defined.
  1367. CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
  1368. to do a dynamic update of a DNS server. To do this, they
  1369. need the hostname of the DHCP requester.
  1370. If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
  1371. of the "hostname" environment variable is passed as
  1372. option 12 to the DHCP server.
  1373. CONFIG_BOOTP_DHCP_REQUEST_DELAY
  1374. A 32bit value in microseconds for a delay between
  1375. receiving a "DHCP Offer" and sending the "DHCP Request".
  1376. This fixes a problem with certain DHCP servers that don't
  1377. respond 100% of the time to a "DHCP request". E.g. On an
  1378. AT91RM9200 processor running at 180MHz, this delay needed
  1379. to be *at least* 15,000 usec before a Windows Server 2003
  1380. DHCP server would reply 100% of the time. I recommend at
  1381. least 50,000 usec to be safe. The alternative is to hope
  1382. that one of the retries will be successful but note that
  1383. the DHCP timeout and retry process takes a longer than
  1384. this delay.
  1385. - Link-local IP address negotiation:
  1386. Negotiate with other link-local clients on the local network
  1387. for an address that doesn't require explicit configuration.
  1388. This is especially useful if a DHCP server cannot be guaranteed
  1389. to exist in all environments that the device must operate.
  1390. See doc/README.link-local for more information.
  1391. - CDP Options:
  1392. CONFIG_CDP_DEVICE_ID
  1393. The device id used in CDP trigger frames.
  1394. CONFIG_CDP_DEVICE_ID_PREFIX
  1395. A two character string which is prefixed to the MAC address
  1396. of the device.
  1397. CONFIG_CDP_PORT_ID
  1398. A printf format string which contains the ascii name of
  1399. the port. Normally is set to "eth%d" which sets
  1400. eth0 for the first Ethernet, eth1 for the second etc.
  1401. CONFIG_CDP_CAPABILITIES
  1402. A 32bit integer which indicates the device capabilities;
  1403. 0x00000010 for a normal host which does not forwards.
  1404. CONFIG_CDP_VERSION
  1405. An ascii string containing the version of the software.
  1406. CONFIG_CDP_PLATFORM
  1407. An ascii string containing the name of the platform.
  1408. CONFIG_CDP_TRIGGER
  1409. A 32bit integer sent on the trigger.
  1410. CONFIG_CDP_POWER_CONSUMPTION
  1411. A 16bit integer containing the power consumption of the
  1412. device in .1 of milliwatts.
  1413. CONFIG_CDP_APPLIANCE_VLAN_TYPE
  1414. A byte containing the id of the VLAN.
  1415. - Status LED: CONFIG_LED_STATUS
  1416. Several configurations allow to display the current
  1417. status using a LED. For instance, the LED will blink
  1418. fast while running U-Boot code, stop blinking as
  1419. soon as a reply to a BOOTP request was received, and
  1420. start blinking slow once the Linux kernel is running
  1421. (supported by a status LED driver in the Linux
  1422. kernel). Defining CONFIG_LED_STATUS enables this
  1423. feature in U-Boot.
  1424. Additional options:
  1425. CONFIG_LED_STATUS_GPIO
  1426. The status LED can be connected to a GPIO pin.
  1427. In such cases, the gpio_led driver can be used as a
  1428. status LED backend implementation. Define CONFIG_LED_STATUS_GPIO
  1429. to include the gpio_led driver in the U-Boot binary.
  1430. CONFIG_GPIO_LED_INVERTED_TABLE
  1431. Some GPIO connected LEDs may have inverted polarity in which
  1432. case the GPIO high value corresponds to LED off state and
  1433. GPIO low value corresponds to LED on state.
  1434. In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
  1435. with a list of GPIO LEDs that have inverted polarity.
  1436. - I2C Support: CONFIG_SYS_I2C
  1437. This enable the NEW i2c subsystem, and will allow you to use
  1438. i2c commands at the u-boot command line (as long as you set
  1439. CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c
  1440. based realtime clock chips or other i2c devices. See
  1441. common/cmd_i2c.c for a description of the command line
  1442. interface.
  1443. ported i2c driver to the new framework:
  1444. - drivers/i2c/soft_i2c.c:
  1445. - activate first bus with CONFIG_SYS_I2C_SOFT define
  1446. CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
  1447. for defining speed and slave address
  1448. - activate second bus with I2C_SOFT_DECLARATIONS2 define
  1449. CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
  1450. for defining speed and slave address
  1451. - activate third bus with I2C_SOFT_DECLARATIONS3 define
  1452. CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
  1453. for defining speed and slave address
  1454. - activate fourth bus with I2C_SOFT_DECLARATIONS4 define
  1455. CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
  1456. for defining speed and slave address
  1457. - drivers/i2c/fsl_i2c.c:
  1458. - activate i2c driver with CONFIG_SYS_I2C_FSL
  1459. define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
  1460. offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
  1461. CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
  1462. bus.
  1463. - If your board supports a second fsl i2c bus, define
  1464. CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
  1465. CONFIG_SYS_FSL_I2C2_SPEED for the speed and
  1466. CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
  1467. second bus.
  1468. - drivers/i2c/tegra_i2c.c:
  1469. - activate this driver with CONFIG_SYS_I2C_TEGRA
  1470. - This driver adds 4 i2c buses with a fix speed from
  1471. 100000 and the slave addr 0!
  1472. - drivers/i2c/ppc4xx_i2c.c
  1473. - activate this driver with CONFIG_SYS_I2C_PPC4XX
  1474. - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0
  1475. - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
  1476. - drivers/i2c/i2c_mxc.c
  1477. - activate this driver with CONFIG_SYS_I2C_MXC
  1478. - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1
  1479. - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2
  1480. - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3
  1481. - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4
  1482. - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED
  1483. - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE
  1484. - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED
  1485. - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE
  1486. - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED
  1487. - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE
  1488. - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED
  1489. - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE
  1490. If those defines are not set, default value is 100000
  1491. for speed, and 0 for slave.
  1492. - drivers/i2c/rcar_i2c.c:
  1493. - activate this driver with CONFIG_SYS_I2C_RCAR
  1494. - This driver adds 4 i2c buses
  1495. - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0
  1496. - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0
  1497. - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1
  1498. - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1
  1499. - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2
  1500. - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2
  1501. - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3
  1502. - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3
  1503. - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses
  1504. - drivers/i2c/sh_i2c.c:
  1505. - activate this driver with CONFIG_SYS_I2C_SH
  1506. - This driver adds from 2 to 5 i2c buses
  1507. - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0
  1508. - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0
  1509. - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1
  1510. - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1
  1511. - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2
  1512. - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2
  1513. - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3
  1514. - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3
  1515. - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4
  1516. - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4
  1517. - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses
  1518. - drivers/i2c/omap24xx_i2c.c
  1519. - activate this driver with CONFIG_SYS_I2C_OMAP24XX
  1520. - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0
  1521. - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0
  1522. - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1
  1523. - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1
  1524. - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2
  1525. - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2
  1526. - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3
  1527. - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3
  1528. - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4
  1529. - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4
  1530. - drivers/i2c/zynq_i2c.c
  1531. - activate this driver with CONFIG_SYS_I2C_ZYNQ
  1532. - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting
  1533. - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr
  1534. - drivers/i2c/s3c24x0_i2c.c:
  1535. - activate this driver with CONFIG_SYS_I2C_S3C24X0
  1536. - This driver adds i2c buses (11 for Exynos5250, Exynos5420
  1537. 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung)
  1538. with a fix speed from 100000 and the slave addr 0!
  1539. - drivers/i2c/ihs_i2c.c
  1540. - activate this driver with CONFIG_SYS_I2C_IHS
  1541. - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0
  1542. - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0
  1543. - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0
  1544. - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1
  1545. - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1
  1546. - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1
  1547. - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2
  1548. - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2
  1549. - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2
  1550. - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3
  1551. - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3
  1552. - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3
  1553. - activate dual channel with CONFIG_SYS_I2C_IHS_DUAL
  1554. - CONFIG_SYS_I2C_IHS_SPEED_0_1 speed channel 0_1
  1555. - CONFIG_SYS_I2C_IHS_SLAVE_0_1 slave addr channel 0_1
  1556. - CONFIG_SYS_I2C_IHS_SPEED_1_1 speed channel 1_1
  1557. - CONFIG_SYS_I2C_IHS_SLAVE_1_1 slave addr channel 1_1
  1558. - CONFIG_SYS_I2C_IHS_SPEED_2_1 speed channel 2_1
  1559. - CONFIG_SYS_I2C_IHS_SLAVE_2_1 slave addr channel 2_1
  1560. - CONFIG_SYS_I2C_IHS_SPEED_3_1 speed channel 3_1
  1561. - CONFIG_SYS_I2C_IHS_SLAVE_3_1 slave addr channel 3_1
  1562. additional defines:
  1563. CONFIG_SYS_NUM_I2C_BUSES
  1564. Hold the number of i2c buses you want to use.
  1565. CONFIG_SYS_I2C_DIRECT_BUS
  1566. define this, if you don't use i2c muxes on your hardware.
  1567. if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
  1568. omit this define.
  1569. CONFIG_SYS_I2C_MAX_HOPS
  1570. define how many muxes are maximal consecutively connected
  1571. on one i2c bus. If you not use i2c muxes, omit this
  1572. define.
  1573. CONFIG_SYS_I2C_BUSES
  1574. hold a list of buses you want to use, only used if
  1575. CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
  1576. a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
  1577. CONFIG_SYS_NUM_I2C_BUSES = 9:
  1578. CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
  1579. {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
  1580. {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
  1581. {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
  1582. {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
  1583. {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
  1584. {1, {I2C_NULL_HOP}}, \
  1585. {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
  1586. {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
  1587. }
  1588. which defines
  1589. bus 0 on adapter 0 without a mux
  1590. bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
  1591. bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
  1592. bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
  1593. bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
  1594. bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
  1595. bus 6 on adapter 1 without a mux
  1596. bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
  1597. bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
  1598. If you do not have i2c muxes on your board, omit this define.
  1599. - Legacy I2C Support:
  1600. If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
  1601. then the following macros need to be defined (examples are
  1602. from include/configs/lwmon.h):
  1603. I2C_INIT
  1604. (Optional). Any commands necessary to enable the I2C
  1605. controller or configure ports.
  1606. eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
  1607. I2C_ACTIVE
  1608. The code necessary to make the I2C data line active
  1609. (driven). If the data line is open collector, this
  1610. define can be null.
  1611. eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
  1612. I2C_TRISTATE
  1613. The code necessary to make the I2C data line tri-stated
  1614. (inactive). If the data line is open collector, this
  1615. define can be null.
  1616. eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
  1617. I2C_READ
  1618. Code that returns true if the I2C data line is high,
  1619. false if it is low.
  1620. eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
  1621. I2C_SDA(bit)
  1622. If <bit> is true, sets the I2C data line high. If it
  1623. is false, it clears it (low).
  1624. eg: #define I2C_SDA(bit) \
  1625. if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
  1626. else immr->im_cpm.cp_pbdat &= ~PB_SDA
  1627. I2C_SCL(bit)
  1628. If <bit> is true, sets the I2C clock line high. If it
  1629. is false, it clears it (low).
  1630. eg: #define I2C_SCL(bit) \
  1631. if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
  1632. else immr->im_cpm.cp_pbdat &= ~PB_SCL
  1633. I2C_DELAY
  1634. This delay is invoked four times per clock cycle so this
  1635. controls the rate of data transfer. The data rate thus
  1636. is 1 / (I2C_DELAY * 4). Often defined to be something
  1637. like:
  1638. #define I2C_DELAY udelay(2)
  1639. CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
  1640. If your arch supports the generic GPIO framework (asm/gpio.h),
  1641. then you may alternatively define the two GPIOs that are to be
  1642. used as SCL / SDA. Any of the previous I2C_xxx macros will
  1643. have GPIO-based defaults assigned to them as appropriate.
  1644. You should define these to the GPIO value as given directly to
  1645. the generic GPIO functions.
  1646. CONFIG_SYS_I2C_INIT_BOARD
  1647. When a board is reset during an i2c bus transfer
  1648. chips might think that the current transfer is still
  1649. in progress. On some boards it is possible to access
  1650. the i2c SCLK line directly, either by using the
  1651. processor pin as a GPIO or by having a second pin
  1652. connected to the bus. If this option is defined a
  1653. custom i2c_init_board() routine in boards/xxx/board.c
  1654. is run early in the boot sequence.
  1655. CONFIG_I2C_MULTI_BUS
  1656. This option allows the use of multiple I2C buses, each of which
  1657. must have a controller. At any point in time, only one bus is
  1658. active. To switch to a different bus, use the 'i2c dev' command.
  1659. Note that bus numbering is zero-based.
  1660. CONFIG_SYS_I2C_NOPROBES
  1661. This option specifies a list of I2C devices that will be skipped
  1662. when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
  1663. is set, specify a list of bus-device pairs. Otherwise, specify
  1664. a 1D array of device addresses
  1665. e.g.
  1666. #undef CONFIG_I2C_MULTI_BUS
  1667. #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
  1668. will skip addresses 0x50 and 0x68 on a board with one I2C bus
  1669. #define CONFIG_I2C_MULTI_BUS
  1670. #define CONFIG_SYS_I2C_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
  1671. will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
  1672. CONFIG_SYS_SPD_BUS_NUM
  1673. If defined, then this indicates the I2C bus number for DDR SPD.
  1674. If not defined, then U-Boot assumes that SPD is on I2C bus 0.
  1675. CONFIG_SYS_RTC_BUS_NUM
  1676. If defined, then this indicates the I2C bus number for the RTC.
  1677. If not defined, then U-Boot assumes that RTC is on I2C bus 0.
  1678. CONFIG_SOFT_I2C_READ_REPEATED_START
  1679. defining this will force the i2c_read() function in
  1680. the soft_i2c driver to perform an I2C repeated start
  1681. between writing the address pointer and reading the
  1682. data. If this define is omitted the default behaviour
  1683. of doing a stop-start sequence will be used. Most I2C
  1684. devices can use either method, but some require one or
  1685. the other.
  1686. - SPI Support: CONFIG_SPI
  1687. Enables SPI driver (so far only tested with
  1688. SPI EEPROM, also an instance works with Crystal A/D and
  1689. D/As on the SACSng board)
  1690. CONFIG_SH_SPI
  1691. Enables the driver for SPI controller on SuperH. Currently
  1692. only SH7757 is supported.
  1693. CONFIG_SOFT_SPI
  1694. Enables a software (bit-bang) SPI driver rather than
  1695. using hardware support. This is a general purpose
  1696. driver that only requires three general I/O port pins
  1697. (two outputs, one input) to function. If this is
  1698. defined, the board configuration must define several
  1699. SPI configuration items (port pins to use, etc). For
  1700. an example, see include/configs/sacsng.h.
  1701. CONFIG_HARD_SPI
  1702. Enables a hardware SPI driver for general-purpose reads
  1703. and writes. As with CONFIG_SOFT_SPI, the board configuration
  1704. must define a list of chip-select function pointers.
  1705. Currently supported on some MPC8xxx processors. For an
  1706. example, see include/configs/mpc8349emds.h.
  1707. CONFIG_MXC_SPI
  1708. Enables the driver for the SPI controllers on i.MX and MXC
  1709. SoCs. Currently i.MX31/35/51 are supported.
  1710. CONFIG_SYS_SPI_MXC_WAIT
  1711. Timeout for waiting until spi transfer completed.
  1712. default: (CONFIG_SYS_HZ/100) /* 10 ms */
  1713. - FPGA Support: CONFIG_FPGA
  1714. Enables FPGA subsystem.
  1715. CONFIG_FPGA_<vendor>
  1716. Enables support for specific chip vendors.
  1717. (ALTERA, XILINX)
  1718. CONFIG_FPGA_<family>
  1719. Enables support for FPGA family.
  1720. (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
  1721. CONFIG_FPGA_COUNT
  1722. Specify the number of FPGA devices to support.
  1723. CONFIG_SYS_FPGA_PROG_FEEDBACK
  1724. Enable printing of hash marks during FPGA configuration.
  1725. CONFIG_SYS_FPGA_CHECK_BUSY
  1726. Enable checks on FPGA configuration interface busy
  1727. status by the configuration function. This option
  1728. will require a board or device specific function to
  1729. be written.
  1730. CONFIG_FPGA_DELAY
  1731. If defined, a function that provides delays in the FPGA
  1732. configuration driver.
  1733. CONFIG_SYS_FPGA_CHECK_CTRLC
  1734. Allow Control-C to interrupt FPGA configuration
  1735. CONFIG_SYS_FPGA_CHECK_ERROR
  1736. Check for configuration errors during FPGA bitfile
  1737. loading. For example, abort during Virtex II
  1738. configuration if the INIT_B line goes low (which
  1739. indicated a CRC error).
  1740. CONFIG_SYS_FPGA_WAIT_INIT
  1741. Maximum time to wait for the INIT_B line to de-assert
  1742. after PROB_B has been de-asserted during a Virtex II
  1743. FPGA configuration sequence. The default time is 500
  1744. ms.
  1745. CONFIG_SYS_FPGA_WAIT_BUSY
  1746. Maximum time to wait for BUSY to de-assert during
  1747. Virtex II FPGA configuration. The default is 5 ms.
  1748. CONFIG_SYS_FPGA_WAIT_CONFIG
  1749. Time to wait after FPGA configuration. The default is
  1750. 200 ms.
  1751. - Configuration Management:
  1752. CONFIG_BUILD_TARGET
  1753. Some SoCs need special image types (e.g. U-Boot binary
  1754. with a special header) as build targets. By defining
  1755. CONFIG_BUILD_TARGET in the SoC / board header, this
  1756. special image will be automatically built upon calling
  1757. make / buildman.
  1758. CONFIG_IDENT_STRING
  1759. If defined, this string will be added to the U-Boot
  1760. version information (U_BOOT_VERSION)
  1761. - Vendor Parameter Protection:
  1762. U-Boot considers the values of the environment
  1763. variables "serial#" (Board Serial Number) and
  1764. "ethaddr" (Ethernet Address) to be parameters that
  1765. are set once by the board vendor / manufacturer, and
  1766. protects these variables from casual modification by
  1767. the user. Once set, these variables are read-only,
  1768. and write or delete attempts are rejected. You can
  1769. change this behaviour:
  1770. If CONFIG_ENV_OVERWRITE is #defined in your config
  1771. file, the write protection for vendor parameters is
  1772. completely disabled. Anybody can change or delete
  1773. these parameters.
  1774. Alternatively, if you define _both_ an ethaddr in the
  1775. default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
  1776. Ethernet address is installed in the environment,
  1777. which can be changed exactly ONCE by the user. [The
  1778. serial# is unaffected by this, i. e. it remains
  1779. read-only.]
  1780. The same can be accomplished in a more flexible way
  1781. for any variable by configuring the type of access
  1782. to allow for those variables in the ".flags" variable
  1783. or define CONFIG_ENV_FLAGS_LIST_STATIC.
  1784. - Protected RAM:
  1785. CONFIG_PRAM
  1786. Define this variable to enable the reservation of
  1787. "protected RAM", i. e. RAM which is not overwritten
  1788. by U-Boot. Define CONFIG_PRAM to hold the number of
  1789. kB you want to reserve for pRAM. You can overwrite
  1790. this default value by defining an environment
  1791. variable "pram" to the number of kB you want to
  1792. reserve. Note that the board info structure will
  1793. still show the full amount of RAM. If pRAM is
  1794. reserved, a new environment variable "mem" will
  1795. automatically be defined to hold the amount of
  1796. remaining RAM in a form that can be passed as boot
  1797. argument to Linux, for instance like that:
  1798. setenv bootargs ... mem=\${mem}
  1799. saveenv
  1800. This way you can tell Linux not to use this memory,
  1801. either, which results in a memory region that will
  1802. not be affected by reboots.
  1803. *WARNING* If your board configuration uses automatic
  1804. detection of the RAM size, you must make sure that
  1805. this memory test is non-destructive. So far, the
  1806. following board configurations are known to be
  1807. "pRAM-clean":
  1808. IVMS8, IVML24, SPD8xx,
  1809. HERMES, IP860, RPXlite, LWMON,
  1810. FLAGADM
  1811. - Access to physical memory region (> 4GB)
  1812. Some basic support is provided for operations on memory not
  1813. normally accessible to U-Boot - e.g. some architectures
  1814. support access to more than 4GB of memory on 32-bit
  1815. machines using physical address extension or similar.
  1816. Define CONFIG_PHYSMEM to access this basic support, which
  1817. currently only supports clearing the memory.
  1818. - Error Recovery:
  1819. CONFIG_PANIC_HANG
  1820. Define this variable to stop the system in case of a
  1821. fatal error, so that you have to reset it manually.
  1822. This is probably NOT a good idea for an embedded
  1823. system where you want the system to reboot
  1824. automatically as fast as possible, but it may be
  1825. useful during development since you can try to debug
  1826. the conditions that lead to the situation.
  1827. CONFIG_NET_RETRY_COUNT
  1828. This variable defines the number of retries for
  1829. network operations like ARP, RARP, TFTP, or BOOTP
  1830. before giving up the operation. If not defined, a
  1831. default value of 5 is used.
  1832. CONFIG_ARP_TIMEOUT
  1833. Timeout waiting for an ARP reply in milliseconds.
  1834. CONFIG_NFS_TIMEOUT
  1835. Timeout in milliseconds used in NFS protocol.
  1836. If you encounter "ERROR: Cannot umount" in nfs command,
  1837. try longer timeout such as
  1838. #define CONFIG_NFS_TIMEOUT 10000UL
  1839. - Command Interpreter:
  1840. CONFIG_AUTO_COMPLETE
  1841. Enable auto completion of commands using TAB.
  1842. CONFIG_SYS_PROMPT_HUSH_PS2
  1843. This defines the secondary prompt string, which is
  1844. printed when the command interpreter needs more input
  1845. to complete a command. Usually "> ".
  1846. Note:
  1847. In the current implementation, the local variables
  1848. space and global environment variables space are
  1849. separated. Local variables are those you define by
  1850. simply typing `name=value'. To access a local
  1851. variable later on, you have write `$name' or
  1852. `${name}'; to execute the contents of a variable
  1853. directly type `$name' at the command prompt.
  1854. Global environment variables are those you use
  1855. setenv/printenv to work with. To run a command stored
  1856. in such a variable, you need to use the run command,
  1857. and you must not use the '$' sign to access them.
  1858. To store commands and special characters in a
  1859. variable, please use double quotation marks
  1860. surrounding the whole text of the variable, instead
  1861. of the backslashes before semicolons and special
  1862. symbols.
  1863. - Command Line Editing and History:
  1864. CONFIG_CMDLINE_EDITING
  1865. Enable editing and History functions for interactive
  1866. command line input operations
  1867. - Command Line PS1/PS2 support:
  1868. CONFIG_CMDLINE_PS_SUPPORT
  1869. Enable support for changing the command prompt string
  1870. at run-time. Only static string is supported so far.
  1871. The string is obtained from environment variables PS1
  1872. and PS2.
  1873. - Default Environment:
  1874. CONFIG_EXTRA_ENV_SETTINGS
  1875. Define this to contain any number of null terminated
  1876. strings (variable = value pairs) that will be part of
  1877. the default environment compiled into the boot image.
  1878. For example, place something like this in your
  1879. board's config file:
  1880. #define CONFIG_EXTRA_ENV_SETTINGS \
  1881. "myvar1=value1\0" \
  1882. "myvar2=value2\0"
  1883. Warning: This method is based on knowledge about the
  1884. internal format how the environment is stored by the
  1885. U-Boot code. This is NOT an official, exported
  1886. interface! Although it is unlikely that this format
  1887. will change soon, there is no guarantee either.
  1888. You better know what you are doing here.
  1889. Note: overly (ab)use of the default environment is
  1890. discouraged. Make sure to check other ways to preset
  1891. the environment like the "source" command or the
  1892. boot command first.
  1893. CONFIG_ENV_VARS_UBOOT_CONFIG
  1894. Define this in order to add variables describing the
  1895. U-Boot build configuration to the default environment.
  1896. These will be named arch, cpu, board, vendor, and soc.
  1897. Enabling this option will cause the following to be defined:
  1898. - CONFIG_SYS_ARCH
  1899. - CONFIG_SYS_CPU
  1900. - CONFIG_SYS_BOARD
  1901. - CONFIG_SYS_VENDOR
  1902. - CONFIG_SYS_SOC
  1903. CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
  1904. Define this in order to add variables describing certain
  1905. run-time determined information about the hardware to the
  1906. environment. These will be named board_name, board_rev.
  1907. CONFIG_DELAY_ENVIRONMENT
  1908. Normally the environment is loaded when the board is
  1909. initialised so that it is available to U-Boot. This inhibits
  1910. that so that the environment is not available until
  1911. explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
  1912. this is instead controlled by the value of
  1913. /config/load-environment.
  1914. - DataFlash Support:
  1915. CONFIG_HAS_DATAFLASH
  1916. Defining this option enables DataFlash features and
  1917. allows to read/write in Dataflash via the standard
  1918. commands cp, md...
  1919. - Serial Flash support
  1920. CONFIG_CMD_SF
  1921. Defining this option enables SPI flash commands
  1922. 'sf probe/read/write/erase/update'.
  1923. Usage requires an initial 'probe' to define the serial
  1924. flash parameters, followed by read/write/erase/update
  1925. commands.
  1926. The following defaults may be provided by the platform
  1927. to handle the common case when only a single serial
  1928. flash is present on the system.
  1929. CONFIG_SF_DEFAULT_BUS Bus identifier
  1930. CONFIG_SF_DEFAULT_CS Chip-select
  1931. CONFIG_SF_DEFAULT_MODE (see include/spi.h)
  1932. CONFIG_SF_DEFAULT_SPEED in Hz
  1933. CONFIG_CMD_SF_TEST
  1934. Define this option to include a destructive SPI flash
  1935. test ('sf test').
  1936. - SystemACE Support:
  1937. CONFIG_SYSTEMACE
  1938. Adding this option adds support for Xilinx SystemACE
  1939. chips attached via some sort of local bus. The address
  1940. of the chip must also be defined in the
  1941. CONFIG_SYS_SYSTEMACE_BASE macro. For example:
  1942. #define CONFIG_SYSTEMACE
  1943. #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
  1944. When SystemACE support is added, the "ace" device type
  1945. becomes available to the fat commands, i.e. fatls.
  1946. - TFTP Fixed UDP Port:
  1947. CONFIG_TFTP_PORT
  1948. If this is defined, the environment variable tftpsrcp
  1949. is used to supply the TFTP UDP source port value.
  1950. If tftpsrcp isn't defined, the normal pseudo-random port
  1951. number generator is used.
  1952. Also, the environment variable tftpdstp is used to supply
  1953. the TFTP UDP destination port value. If tftpdstp isn't
  1954. defined, the normal port 69 is used.
  1955. The purpose for tftpsrcp is to allow a TFTP server to
  1956. blindly start the TFTP transfer using the pre-configured
  1957. target IP address and UDP port. This has the effect of
  1958. "punching through" the (Windows XP) firewall, allowing
  1959. the remainder of the TFTP transfer to proceed normally.
  1960. A better solution is to properly configure the firewall,
  1961. but sometimes that is not allowed.
  1962. - bootcount support:
  1963. CONFIG_BOOTCOUNT_LIMIT
  1964. This enables the bootcounter support, see:
  1965. http://www.denx.de/wiki/DULG/UBootBootCountLimit
  1966. CONFIG_AT91SAM9XE
  1967. enable special bootcounter support on at91sam9xe based boards.
  1968. CONFIG_SOC_DA8XX
  1969. enable special bootcounter support on da850 based boards.
  1970. CONFIG_BOOTCOUNT_RAM
  1971. enable support for the bootcounter in RAM
  1972. CONFIG_BOOTCOUNT_I2C
  1973. enable support for the bootcounter on an i2c (like RTC) device.
  1974. CONFIG_SYS_I2C_RTC_ADDR = i2c chip address
  1975. CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for
  1976. the bootcounter.
  1977. CONFIG_BOOTCOUNT_ALEN = address len
  1978. - Show boot progress:
  1979. CONFIG_SHOW_BOOT_PROGRESS
  1980. Defining this option allows to add some board-
  1981. specific code (calling a user-provided function
  1982. "show_boot_progress(int)") that enables you to show
  1983. the system's boot progress on some display (for
  1984. example, some LED's) on your board. At the moment,
  1985. the following checkpoints are implemented:
  1986. Legacy uImage format:
  1987. Arg Where When
  1988. 1 common/cmd_bootm.c before attempting to boot an image
  1989. -1 common/cmd_bootm.c Image header has bad magic number
  1990. 2 common/cmd_bootm.c Image header has correct magic number
  1991. -2 common/cmd_bootm.c Image header has bad checksum
  1992. 3 common/cmd_bootm.c Image header has correct checksum
  1993. -3 common/cmd_bootm.c Image data has bad checksum
  1994. 4 common/cmd_bootm.c Image data has correct checksum
  1995. -4 common/cmd_bootm.c Image is for unsupported architecture
  1996. 5 common/cmd_bootm.c Architecture check OK
  1997. -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
  1998. 6 common/cmd_bootm.c Image Type check OK
  1999. -6 common/cmd_bootm.c gunzip uncompression error
  2000. -7 common/cmd_bootm.c Unimplemented compression type
  2001. 7 common/cmd_bootm.c Uncompression OK
  2002. 8 common/cmd_bootm.c No uncompress/copy overwrite error
  2003. -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
  2004. 9 common/image.c Start initial ramdisk verification
  2005. -10 common/image.c Ramdisk header has bad magic number
  2006. -11 common/image.c Ramdisk header has bad checksum
  2007. 10 common/image.c Ramdisk header is OK
  2008. -12 common/image.c Ramdisk data has bad checksum
  2009. 11 common/image.c Ramdisk data has correct checksum
  2010. 12 common/image.c Ramdisk verification complete, start loading
  2011. -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
  2012. 13 common/image.c Start multifile image verification
  2013. 14 common/image.c No initial ramdisk, no multifile, continue.
  2014. 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
  2015. -30 arch/powerpc/lib/board.c Fatal error, hang the system
  2016. -31 post/post.c POST test failed, detected by post_output_backlog()
  2017. -32 post/post.c POST test failed, detected by post_run_single()
  2018. 34 common/cmd_doc.c before loading a Image from a DOC device
  2019. -35 common/cmd_doc.c Bad usage of "doc" command
  2020. 35 common/cmd_doc.c correct usage of "doc" command
  2021. -36 common/cmd_doc.c No boot device
  2022. 36 common/cmd_doc.c correct boot device
  2023. -37 common/cmd_doc.c Unknown Chip ID on boot device
  2024. 37 common/cmd_doc.c correct chip ID found, device available
  2025. -38 common/cmd_doc.c Read Error on boot device
  2026. 38 common/cmd_doc.c reading Image header from DOC device OK
  2027. -39 common/cmd_doc.c Image header has bad magic number
  2028. 39 common/cmd_doc.c Image header has correct magic number
  2029. -40 common/cmd_doc.c Error reading Image from DOC device
  2030. 40 common/cmd_doc.c Image header has correct magic number
  2031. 41 common/cmd_ide.c before loading a Image from a IDE device
  2032. -42 common/cmd_ide.c Bad usage of "ide" command
  2033. 42 common/cmd_ide.c correct usage of "ide" command
  2034. -43 common/cmd_ide.c No boot device
  2035. 43 common/cmd_ide.c boot device found
  2036. -44 common/cmd_ide.c Device not available
  2037. 44 common/cmd_ide.c Device available
  2038. -45 common/cmd_ide.c wrong partition selected
  2039. 45 common/cmd_ide.c partition selected
  2040. -46 common/cmd_ide.c Unknown partition table
  2041. 46 common/cmd_ide.c valid partition table found
  2042. -47 common/cmd_ide.c Invalid partition type
  2043. 47 common/cmd_ide.c correct partition type
  2044. -48 common/cmd_ide.c Error reading Image Header on boot device
  2045. 48 common/cmd_ide.c reading Image Header from IDE device OK
  2046. -49 common/cmd_ide.c Image header has bad magic number
  2047. 49 common/cmd_ide.c Image header has correct magic number
  2048. -50 common/cmd_ide.c Image header has bad checksum
  2049. 50 common/cmd_ide.c Image header has correct checksum
  2050. -51 common/cmd_ide.c Error reading Image from IDE device
  2051. 51 common/cmd_ide.c reading Image from IDE device OK
  2052. 52 common/cmd_nand.c before loading a Image from a NAND device
  2053. -53 common/cmd_nand.c Bad usage of "nand" command
  2054. 53 common/cmd_nand.c correct usage of "nand" command
  2055. -54 common/cmd_nand.c No boot device
  2056. 54 common/cmd_nand.c boot device found
  2057. -55 common/cmd_nand.c Unknown Chip ID on boot device
  2058. 55 common/cmd_nand.c correct chip ID found, device available
  2059. -56 common/cmd_nand.c Error reading Image Header on boot device
  2060. 56 common/cmd_nand.c reading Image Header from NAND device OK
  2061. -57 common/cmd_nand.c Image header has bad magic number
  2062. 57 common/cmd_nand.c Image header has correct magic number
  2063. -58 common/cmd_nand.c Error reading Image from NAND device
  2064. 58 common/cmd_nand.c reading Image from NAND device OK
  2065. -60 common/env_common.c Environment has a bad CRC, using default
  2066. 64 net/eth.c starting with Ethernet configuration.
  2067. -64 net/eth.c no Ethernet found.
  2068. 65 net/eth.c Ethernet found.
  2069. -80 common/cmd_net.c usage wrong
  2070. 80 common/cmd_net.c before calling net_loop()
  2071. -81 common/cmd_net.c some error in net_loop() occurred
  2072. 81 common/cmd_net.c net_loop() back without error
  2073. -82 common/cmd_net.c size == 0 (File with size 0 loaded)
  2074. 82 common/cmd_net.c trying automatic boot
  2075. 83 common/cmd_net.c running "source" command
  2076. -83 common/cmd_net.c some error in automatic boot or "source" command
  2077. 84 common/cmd_net.c end without errors
  2078. FIT uImage format:
  2079. Arg Where When
  2080. 100 common/cmd_bootm.c Kernel FIT Image has correct format
  2081. -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
  2082. 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
  2083. -101 common/cmd_bootm.c Can't get configuration for kernel subimage
  2084. 102 common/cmd_bootm.c Kernel unit name specified
  2085. -103 common/cmd_bootm.c Can't get kernel subimage node offset
  2086. 103 common/cmd_bootm.c Found configuration node
  2087. 104 common/cmd_bootm.c Got kernel subimage node offset
  2088. -104 common/cmd_bootm.c Kernel subimage hash verification failed
  2089. 105 common/cmd_bootm.c Kernel subimage hash verification OK
  2090. -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
  2091. 106 common/cmd_bootm.c Architecture check OK
  2092. -106 common/cmd_bootm.c Kernel subimage has wrong type
  2093. 107 common/cmd_bootm.c Kernel subimage type OK
  2094. -107 common/cmd_bootm.c Can't get kernel subimage data/size
  2095. 108 common/cmd_bootm.c Got kernel subimage data/size
  2096. -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
  2097. -109 common/cmd_bootm.c Can't get kernel subimage type
  2098. -110 common/cmd_bootm.c Can't get kernel subimage comp
  2099. -111 common/cmd_bootm.c Can't get kernel subimage os
  2100. -112 common/cmd_bootm.c Can't get kernel subimage load address
  2101. -113 common/cmd_bootm.c Image uncompress/copy overwrite error
  2102. 120 common/image.c Start initial ramdisk verification
  2103. -120 common/image.c Ramdisk FIT image has incorrect format
  2104. 121 common/image.c Ramdisk FIT image has correct format
  2105. 122 common/image.c No ramdisk subimage unit name, using configuration
  2106. -122 common/image.c Can't get configuration for ramdisk subimage
  2107. 123 common/image.c Ramdisk unit name specified
  2108. -124 common/image.c Can't get ramdisk subimage node offset
  2109. 125 common/image.c Got ramdisk subimage node offset
  2110. -125 common/image.c Ramdisk subimage hash verification failed
  2111. 126 common/image.c Ramdisk subimage hash verification OK
  2112. -126 common/image.c Ramdisk subimage for unsupported architecture
  2113. 127 common/image.c Architecture check OK
  2114. -127 common/image.c Can't get ramdisk subimage data/size
  2115. 128 common/image.c Got ramdisk subimage data/size
  2116. 129 common/image.c Can't get ramdisk load address
  2117. -129 common/image.c Got ramdisk load address
  2118. -130 common/cmd_doc.c Incorrect FIT image format
  2119. 131 common/cmd_doc.c FIT image format OK
  2120. -140 common/cmd_ide.c Incorrect FIT image format
  2121. 141 common/cmd_ide.c FIT image format OK
  2122. -150 common/cmd_nand.c Incorrect FIT image format
  2123. 151 common/cmd_nand.c FIT image format OK
  2124. - legacy image format:
  2125. CONFIG_IMAGE_FORMAT_LEGACY
  2126. enables the legacy image format support in U-Boot.
  2127. Default:
  2128. enabled if CONFIG_FIT_SIGNATURE is not defined.
  2129. CONFIG_DISABLE_IMAGE_LEGACY
  2130. disable the legacy image format
  2131. This define is introduced, as the legacy image format is
  2132. enabled per default for backward compatibility.
  2133. - Standalone program support:
  2134. CONFIG_STANDALONE_LOAD_ADDR
  2135. This option defines a board specific value for the
  2136. address where standalone program gets loaded, thus
  2137. overwriting the architecture dependent default
  2138. settings.
  2139. - Frame Buffer Address:
  2140. CONFIG_FB_ADDR
  2141. Define CONFIG_FB_ADDR if you want to use specific
  2142. address for frame buffer. This is typically the case
  2143. when using a graphics controller has separate video
  2144. memory. U-Boot will then place the frame buffer at
  2145. the given address instead of dynamically reserving it
  2146. in system RAM by calling lcd_setmem(), which grabs
  2147. the memory for the frame buffer depending on the
  2148. configured panel size.
  2149. Please see board_init_f function.
  2150. - Automatic software updates via TFTP server
  2151. CONFIG_UPDATE_TFTP
  2152. CONFIG_UPDATE_TFTP_CNT_MAX
  2153. CONFIG_UPDATE_TFTP_MSEC_MAX
  2154. These options enable and control the auto-update feature;
  2155. for a more detailed description refer to doc/README.update.
  2156. - MTD Support (mtdparts command, UBI support)
  2157. CONFIG_MTD_DEVICE
  2158. Adds the MTD device infrastructure from the Linux kernel.
  2159. Needed for mtdparts command support.
  2160. CONFIG_MTD_PARTITIONS
  2161. Adds the MTD partitioning infrastructure from the Linux
  2162. kernel. Needed for UBI support.
  2163. - UBI support
  2164. CONFIG_CMD_UBI
  2165. Adds commands for interacting with MTD partitions formatted
  2166. with the UBI flash translation layer
  2167. Requires also defining CONFIG_RBTREE
  2168. CONFIG_UBI_SILENCE_MSG
  2169. Make the verbose messages from UBI stop printing. This leaves
  2170. warnings and errors enabled.
  2171. CONFIG_MTD_UBI_WL_THRESHOLD
  2172. This parameter defines the maximum difference between the highest
  2173. erase counter value and the lowest erase counter value of eraseblocks
  2174. of UBI devices. When this threshold is exceeded, UBI starts performing
  2175. wear leveling by means of moving data from eraseblock with low erase
  2176. counter to eraseblocks with high erase counter.
  2177. The default value should be OK for SLC NAND flashes, NOR flashes and
  2178. other flashes which have eraseblock life-cycle 100000 or more.
  2179. However, in case of MLC NAND flashes which typically have eraseblock
  2180. life-cycle less than 10000, the threshold should be lessened (e.g.,
  2181. to 128 or 256, although it does not have to be power of 2).
  2182. default: 4096
  2183. CONFIG_MTD_UBI_BEB_LIMIT
  2184. This option specifies the maximum bad physical eraseblocks UBI
  2185. expects on the MTD device (per 1024 eraseblocks). If the
  2186. underlying flash does not admit of bad eraseblocks (e.g. NOR
  2187. flash), this value is ignored.
  2188. NAND datasheets often specify the minimum and maximum NVM
  2189. (Number of Valid Blocks) for the flashes' endurance lifetime.
  2190. The maximum expected bad eraseblocks per 1024 eraseblocks
  2191. then can be calculated as "1024 * (1 - MinNVB / MaxNVB)",
  2192. which gives 20 for most NANDs (MaxNVB is basically the total
  2193. count of eraseblocks on the chip).
  2194. To put it differently, if this value is 20, UBI will try to
  2195. reserve about 1.9% of physical eraseblocks for bad blocks
  2196. handling. And that will be 1.9% of eraseblocks on the entire
  2197. NAND chip, not just the MTD partition UBI attaches. This means
  2198. that if you have, say, a NAND flash chip admits maximum 40 bad
  2199. eraseblocks, and it is split on two MTD partitions of the same
  2200. size, UBI will reserve 40 eraseblocks when attaching a
  2201. partition.
  2202. default: 20
  2203. CONFIG_MTD_UBI_FASTMAP
  2204. Fastmap is a mechanism which allows attaching an UBI device
  2205. in nearly constant time. Instead of scanning the whole MTD device it
  2206. only has to locate a checkpoint (called fastmap) on the device.
  2207. The on-flash fastmap contains all information needed to attach
  2208. the device. Using fastmap makes only sense on large devices where
  2209. attaching by scanning takes long. UBI will not automatically install
  2210. a fastmap on old images, but you can set the UBI parameter
  2211. CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note
  2212. that fastmap-enabled images are still usable with UBI implementations
  2213. without fastmap support. On typical flash devices the whole fastmap
  2214. fits into one PEB. UBI will reserve PEBs to hold two fastmaps.
  2215. CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT
  2216. Set this parameter to enable fastmap automatically on images
  2217. without a fastmap.
  2218. default: 0
  2219. CONFIG_MTD_UBI_FM_DEBUG
  2220. Enable UBI fastmap debug
  2221. default: 0
  2222. - UBIFS support
  2223. CONFIG_CMD_UBIFS
  2224. Adds commands for interacting with UBI volumes formatted as
  2225. UBIFS. UBIFS is read-only in u-boot.
  2226. Requires UBI support as well as CONFIG_LZO
  2227. CONFIG_UBIFS_SILENCE_MSG
  2228. Make the verbose messages from UBIFS stop printing. This leaves
  2229. warnings and errors enabled.
  2230. - SPL framework
  2231. CONFIG_SPL
  2232. Enable building of SPL globally.
  2233. CONFIG_SPL_LDSCRIPT
  2234. LDSCRIPT for linking the SPL binary.
  2235. CONFIG_SPL_MAX_FOOTPRINT
  2236. Maximum size in memory allocated to the SPL, BSS included.
  2237. When defined, the linker checks that the actual memory
  2238. used by SPL from _start to __bss_end does not exceed it.
  2239. CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
  2240. must not be both defined at the same time.
  2241. CONFIG_SPL_MAX_SIZE
  2242. Maximum size of the SPL image (text, data, rodata, and
  2243. linker lists sections), BSS excluded.
  2244. When defined, the linker checks that the actual size does
  2245. not exceed it.
  2246. CONFIG_SPL_TEXT_BASE
  2247. TEXT_BASE for linking the SPL binary.
  2248. CONFIG_SPL_RELOC_TEXT_BASE
  2249. Address to relocate to. If unspecified, this is equal to
  2250. CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
  2251. CONFIG_SPL_BSS_START_ADDR
  2252. Link address for the BSS within the SPL binary.
  2253. CONFIG_SPL_BSS_MAX_SIZE
  2254. Maximum size in memory allocated to the SPL BSS.
  2255. When defined, the linker checks that the actual memory used
  2256. by SPL from __bss_start to __bss_end does not exceed it.
  2257. CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
  2258. must not be both defined at the same time.
  2259. CONFIG_SPL_STACK
  2260. Adress of the start of the stack SPL will use
  2261. CONFIG_SPL_PANIC_ON_RAW_IMAGE
  2262. When defined, SPL will panic() if the image it has
  2263. loaded does not have a signature.
  2264. Defining this is useful when code which loads images
  2265. in SPL cannot guarantee that absolutely all read errors
  2266. will be caught.
  2267. An example is the LPC32XX MLC NAND driver, which will
  2268. consider that a completely unreadable NAND block is bad,
  2269. and thus should be skipped silently.
  2270. CONFIG_SPL_RELOC_STACK
  2271. Adress of the start of the stack SPL will use after
  2272. relocation. If unspecified, this is equal to
  2273. CONFIG_SPL_STACK.
  2274. CONFIG_SYS_SPL_MALLOC_START
  2275. Starting address of the malloc pool used in SPL.
  2276. When this option is set the full malloc is used in SPL and
  2277. it is set up by spl_init() and before that, the simple malloc()
  2278. can be used if CONFIG_SYS_MALLOC_F is defined.
  2279. CONFIG_SYS_SPL_MALLOC_SIZE
  2280. The size of the malloc pool used in SPL.
  2281. CONFIG_SPL_FRAMEWORK
  2282. Enable the SPL framework under common/. This framework
  2283. supports MMC, NAND and YMODEM loading of U-Boot and NAND
  2284. NAND loading of the Linux Kernel.
  2285. CONFIG_SPL_OS_BOOT
  2286. Enable booting directly to an OS from SPL.
  2287. See also: doc/README.falcon
  2288. CONFIG_SPL_DISPLAY_PRINT
  2289. For ARM, enable an optional function to print more information
  2290. about the running system.
  2291. CONFIG_SPL_INIT_MINIMAL
  2292. Arch init code should be built for a very small image
  2293. CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION
  2294. Partition on the MMC to load U-Boot from when the MMC is being
  2295. used in raw mode
  2296. CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
  2297. Sector to load kernel uImage from when MMC is being
  2298. used in raw mode (for Falcon mode)
  2299. CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
  2300. CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
  2301. Sector and number of sectors to load kernel argument
  2302. parameters from when MMC is being used in raw mode
  2303. (for falcon mode)
  2304. CONFIG_SYS_MMCSD_FS_BOOT_PARTITION
  2305. Partition on the MMC to load U-Boot from when the MMC is being
  2306. used in fs mode
  2307. CONFIG_SPL_FS_LOAD_PAYLOAD_NAME
  2308. Filename to read to load U-Boot when reading from filesystem
  2309. CONFIG_SPL_FS_LOAD_KERNEL_NAME
  2310. Filename to read to load kernel uImage when reading
  2311. from filesystem (for Falcon mode)
  2312. CONFIG_SPL_FS_LOAD_ARGS_NAME
  2313. Filename to read to load kernel argument parameters
  2314. when reading from filesystem (for Falcon mode)
  2315. CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
  2316. Set this for NAND SPL on PPC mpc83xx targets, so that
  2317. start.S waits for the rest of the SPL to load before
  2318. continuing (the hardware starts execution after just
  2319. loading the first page rather than the full 4K).
  2320. CONFIG_SPL_SKIP_RELOCATE
  2321. Avoid SPL relocation
  2322. CONFIG_SPL_NAND_BASE
  2323. Include nand_base.c in the SPL. Requires
  2324. CONFIG_SPL_NAND_DRIVERS.
  2325. CONFIG_SPL_NAND_DRIVERS
  2326. SPL uses normal NAND drivers, not minimal drivers.
  2327. CONFIG_SPL_NAND_ECC
  2328. Include standard software ECC in the SPL
  2329. CONFIG_SPL_NAND_SIMPLE
  2330. Support for NAND boot using simple NAND drivers that
  2331. expose the cmd_ctrl() interface.
  2332. CONFIG_SPL_UBI
  2333. Support for a lightweight UBI (fastmap) scanner and
  2334. loader
  2335. CONFIG_SPL_NAND_RAW_ONLY
  2336. Support to boot only raw u-boot.bin images. Use this only
  2337. if you need to save space.
  2338. CONFIG_SPL_COMMON_INIT_DDR
  2339. Set for common ddr init with serial presence detect in
  2340. SPL binary.
  2341. CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
  2342. CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
  2343. CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
  2344. CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
  2345. CONFIG_SYS_NAND_ECCBYTES
  2346. Defines the size and behavior of the NAND that SPL uses
  2347. to read U-Boot
  2348. CONFIG_SPL_NAND_BOOT
  2349. Add support NAND boot
  2350. CONFIG_SYS_NAND_U_BOOT_OFFS
  2351. Location in NAND to read U-Boot from
  2352. CONFIG_SYS_NAND_U_BOOT_DST
  2353. Location in memory to load U-Boot to
  2354. CONFIG_SYS_NAND_U_BOOT_SIZE
  2355. Size of image to load
  2356. CONFIG_SYS_NAND_U_BOOT_START
  2357. Entry point in loaded image to jump to
  2358. CONFIG_SYS_NAND_HW_ECC_OOBFIRST
  2359. Define this if you need to first read the OOB and then the
  2360. data. This is used, for example, on davinci platforms.
  2361. CONFIG_SPL_OMAP3_ID_NAND
  2362. Support for an OMAP3-specific set of functions to return the
  2363. ID and MFR of the first attached NAND chip, if present.
  2364. CONFIG_SPL_RAM_DEVICE
  2365. Support for running image already present in ram, in SPL binary
  2366. CONFIG_SPL_PAD_TO
  2367. Image offset to which the SPL should be padded before appending
  2368. the SPL payload. By default, this is defined as
  2369. CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
  2370. CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
  2371. payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
  2372. CONFIG_SPL_TARGET
  2373. Final target image containing SPL and payload. Some SPLs
  2374. use an arch-specific makefile fragment instead, for
  2375. example if more than one image needs to be produced.
  2376. CONFIG_FIT_SPL_PRINT
  2377. Printing information about a FIT image adds quite a bit of
  2378. code to SPL. So this is normally disabled in SPL. Use this
  2379. option to re-enable it. This will affect the output of the
  2380. bootm command when booting a FIT image.
  2381. - TPL framework
  2382. CONFIG_TPL
  2383. Enable building of TPL globally.
  2384. CONFIG_TPL_PAD_TO
  2385. Image offset to which the TPL should be padded before appending
  2386. the TPL payload. By default, this is defined as
  2387. CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
  2388. CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
  2389. payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
  2390. - Interrupt support (PPC):
  2391. There are common interrupt_init() and timer_interrupt()
  2392. for all PPC archs. interrupt_init() calls interrupt_init_cpu()
  2393. for CPU specific initialization. interrupt_init_cpu()
  2394. should set decrementer_count to appropriate value. If
  2395. CPU resets decrementer automatically after interrupt
  2396. (ppc4xx) it should set decrementer_count to zero.
  2397. timer_interrupt() calls timer_interrupt_cpu() for CPU
  2398. specific handling. If board has watchdog / status_led
  2399. / other_activity_monitor it works automatically from
  2400. general timer_interrupt().
  2401. Board initialization settings:
  2402. ------------------------------
  2403. During Initialization u-boot calls a number of board specific functions
  2404. to allow the preparation of board specific prerequisites, e.g. pin setup
  2405. before drivers are initialized. To enable these callbacks the
  2406. following configuration macros have to be defined. Currently this is
  2407. architecture specific, so please check arch/your_architecture/lib/board.c
  2408. typically in board_init_f() and board_init_r().
  2409. - CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
  2410. - CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
  2411. - CONFIG_BOARD_LATE_INIT: Call board_late_init()
  2412. - CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
  2413. Configuration Settings:
  2414. -----------------------
  2415. - CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
  2416. Optionally it can be defined to support 64-bit memory commands.
  2417. - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
  2418. undefine this when you're short of memory.
  2419. - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
  2420. width of the commands listed in the 'help' command output.
  2421. - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
  2422. prompt for user input.
  2423. - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
  2424. - CONFIG_SYS_PBSIZE: Buffer size for Console output
  2425. - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
  2426. - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
  2427. the application (usually a Linux kernel) when it is
  2428. booted
  2429. - CONFIG_SYS_BAUDRATE_TABLE:
  2430. List of legal baudrate settings for this board.
  2431. - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
  2432. Begin and End addresses of the area used by the
  2433. simple memory test.
  2434. - CONFIG_SYS_ALT_MEMTEST:
  2435. Enable an alternate, more extensive memory test.
  2436. - CONFIG_SYS_MEMTEST_SCRATCH:
  2437. Scratch address used by the alternate memory test
  2438. You only need to set this if address zero isn't writeable
  2439. - CONFIG_SYS_MEM_RESERVE_SECURE
  2440. Only implemented for ARMv8 for now.
  2441. If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory
  2442. is substracted from total RAM and won't be reported to OS.
  2443. This memory can be used as secure memory. A variable
  2444. gd->arch.secure_ram is used to track the location. In systems
  2445. the RAM base is not zero, or RAM is divided into banks,
  2446. this variable needs to be recalcuated to get the address.
  2447. - CONFIG_SYS_MEM_TOP_HIDE:
  2448. If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
  2449. this specified memory area will get subtracted from the top
  2450. (end) of RAM and won't get "touched" at all by U-Boot. By
  2451. fixing up gd->ram_size the Linux kernel should gets passed
  2452. the now "corrected" memory size and won't touch it either.
  2453. This should work for arch/ppc and arch/powerpc. Only Linux
  2454. board ports in arch/powerpc with bootwrapper support that
  2455. recalculate the memory size from the SDRAM controller setup
  2456. will have to get fixed in Linux additionally.
  2457. This option can be used as a workaround for the 440EPx/GRx
  2458. CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
  2459. be touched.
  2460. WARNING: Please make sure that this value is a multiple of
  2461. the Linux page size (normally 4k). If this is not the case,
  2462. then the end address of the Linux memory will be located at a
  2463. non page size aligned address and this could cause major
  2464. problems.
  2465. - CONFIG_SYS_LOADS_BAUD_CHANGE:
  2466. Enable temporary baudrate change while serial download
  2467. - CONFIG_SYS_SDRAM_BASE:
  2468. Physical start address of SDRAM. _Must_ be 0 here.
  2469. - CONFIG_SYS_FLASH_BASE:
  2470. Physical start address of Flash memory.
  2471. - CONFIG_SYS_MONITOR_BASE:
  2472. Physical start address of boot monitor code (set by
  2473. make config files to be same as the text base address
  2474. (CONFIG_SYS_TEXT_BASE) used when linking) - same as
  2475. CONFIG_SYS_FLASH_BASE when booting from flash.
  2476. - CONFIG_SYS_MONITOR_LEN:
  2477. Size of memory reserved for monitor code, used to
  2478. determine _at_compile_time_ (!) if the environment is
  2479. embedded within the U-Boot image, or in a separate
  2480. flash sector.
  2481. - CONFIG_SYS_MALLOC_LEN:
  2482. Size of DRAM reserved for malloc() use.
  2483. - CONFIG_SYS_MALLOC_F_LEN
  2484. Size of the malloc() pool for use before relocation. If
  2485. this is defined, then a very simple malloc() implementation
  2486. will become available before relocation. The address is just
  2487. below the global data, and the stack is moved down to make
  2488. space.
  2489. This feature allocates regions with increasing addresses
  2490. within the region. calloc() is supported, but realloc()
  2491. is not available. free() is supported but does nothing.
  2492. The memory will be freed (or in fact just forgotten) when
  2493. U-Boot relocates itself.
  2494. - CONFIG_SYS_MALLOC_SIMPLE
  2495. Provides a simple and small malloc() and calloc() for those
  2496. boards which do not use the full malloc in SPL (which is
  2497. enabled with CONFIG_SYS_SPL_MALLOC_START).
  2498. - CONFIG_SYS_NONCACHED_MEMORY:
  2499. Size of non-cached memory area. This area of memory will be
  2500. typically located right below the malloc() area and mapped
  2501. uncached in the MMU. This is useful for drivers that would
  2502. otherwise require a lot of explicit cache maintenance. For
  2503. some drivers it's also impossible to properly maintain the
  2504. cache. For example if the regions that need to be flushed
  2505. are not a multiple of the cache-line size, *and* padding
  2506. cannot be allocated between the regions to align them (i.e.
  2507. if the HW requires a contiguous array of regions, and the
  2508. size of each region is not cache-aligned), then a flush of
  2509. one region may result in overwriting data that hardware has
  2510. written to another region in the same cache-line. This can
  2511. happen for example in network drivers where descriptors for
  2512. buffers are typically smaller than the CPU cache-line (e.g.
  2513. 16 bytes vs. 32 or 64 bytes).
  2514. Non-cached memory is only supported on 32-bit ARM at present.
  2515. - CONFIG_SYS_BOOTM_LEN:
  2516. Normally compressed uImages are limited to an
  2517. uncompressed size of 8 MBytes. If this is not enough,
  2518. you can define CONFIG_SYS_BOOTM_LEN in your board config file
  2519. to adjust this setting to your needs.
  2520. - CONFIG_SYS_BOOTMAPSZ:
  2521. Maximum size of memory mapped by the startup code of
  2522. the Linux kernel; all data that must be processed by
  2523. the Linux kernel (bd_info, boot arguments, FDT blob if
  2524. used) must be put below this limit, unless "bootm_low"
  2525. environment variable is defined and non-zero. In such case
  2526. all data for the Linux kernel must be between "bootm_low"
  2527. and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
  2528. variable "bootm_mapsize" will override the value of
  2529. CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
  2530. then the value in "bootm_size" will be used instead.
  2531. - CONFIG_SYS_BOOT_RAMDISK_HIGH:
  2532. Enable initrd_high functionality. If defined then the
  2533. initrd_high feature is enabled and the bootm ramdisk subcommand
  2534. is enabled.
  2535. - CONFIG_SYS_BOOT_GET_CMDLINE:
  2536. Enables allocating and saving kernel cmdline in space between
  2537. "bootm_low" and "bootm_low" + BOOTMAPSZ.
  2538. - CONFIG_SYS_BOOT_GET_KBD:
  2539. Enables allocating and saving a kernel copy of the bd_info in
  2540. space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
  2541. - CONFIG_SYS_MAX_FLASH_BANKS:
  2542. Max number of Flash memory banks
  2543. - CONFIG_SYS_MAX_FLASH_SECT:
  2544. Max number of sectors on a Flash chip
  2545. - CONFIG_SYS_FLASH_ERASE_TOUT:
  2546. Timeout for Flash erase operations (in ms)
  2547. - CONFIG_SYS_FLASH_WRITE_TOUT:
  2548. Timeout for Flash write operations (in ms)
  2549. - CONFIG_SYS_FLASH_LOCK_TOUT
  2550. Timeout for Flash set sector lock bit operation (in ms)
  2551. - CONFIG_SYS_FLASH_UNLOCK_TOUT
  2552. Timeout for Flash clear lock bits operation (in ms)
  2553. - CONFIG_SYS_FLASH_PROTECTION
  2554. If defined, hardware flash sectors protection is used
  2555. instead of U-Boot software protection.
  2556. - CONFIG_SYS_DIRECT_FLASH_TFTP:
  2557. Enable TFTP transfers directly to flash memory;
  2558. without this option such a download has to be
  2559. performed in two steps: (1) download to RAM, and (2)
  2560. copy from RAM to flash.
  2561. The two-step approach is usually more reliable, since
  2562. you can check if the download worked before you erase
  2563. the flash, but in some situations (when system RAM is
  2564. too limited to allow for a temporary copy of the
  2565. downloaded image) this option may be very useful.
  2566. - CONFIG_SYS_FLASH_CFI:
  2567. Define if the flash driver uses extra elements in the
  2568. common flash structure for storing flash geometry.
  2569. - CONFIG_FLASH_CFI_DRIVER
  2570. This option also enables the building of the cfi_flash driver
  2571. in the drivers directory
  2572. - CONFIG_FLASH_CFI_MTD
  2573. This option enables the building of the cfi_mtd driver
  2574. in the drivers directory. The driver exports CFI flash
  2575. to the MTD layer.
  2576. - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
  2577. Use buffered writes to flash.
  2578. - CONFIG_FLASH_SPANSION_S29WS_N
  2579. s29ws-n MirrorBit flash has non-standard addresses for buffered
  2580. write commands.
  2581. - CONFIG_SYS_FLASH_QUIET_TEST
  2582. If this option is defined, the common CFI flash doesn't
  2583. print it's warning upon not recognized FLASH banks. This
  2584. is useful, if some of the configured banks are only
  2585. optionally available.
  2586. - CONFIG_FLASH_SHOW_PROGRESS
  2587. If defined (must be an integer), print out countdown
  2588. digits and dots. Recommended value: 45 (9..1) for 80
  2589. column displays, 15 (3..1) for 40 column displays.
  2590. - CONFIG_FLASH_VERIFY
  2591. If defined, the content of the flash (destination) is compared
  2592. against the source after the write operation. An error message
  2593. will be printed when the contents are not identical.
  2594. Please note that this option is useless in nearly all cases,
  2595. since such flash programming errors usually are detected earlier
  2596. while unprotecting/erasing/programming. Please only enable
  2597. this option if you really know what you are doing.
  2598. - CONFIG_SYS_RX_ETH_BUFFER:
  2599. Defines the number of Ethernet receive buffers. On some
  2600. Ethernet controllers it is recommended to set this value
  2601. to 8 or even higher (EEPRO100 or 405 EMAC), since all
  2602. buffers can be full shortly after enabling the interface
  2603. on high Ethernet traffic.
  2604. Defaults to 4 if not defined.
  2605. - CONFIG_ENV_MAX_ENTRIES
  2606. Maximum number of entries in the hash table that is used
  2607. internally to store the environment settings. The default
  2608. setting is supposed to be generous and should work in most
  2609. cases. This setting can be used to tune behaviour; see
  2610. lib/hashtable.c for details.
  2611. - CONFIG_ENV_FLAGS_LIST_DEFAULT
  2612. - CONFIG_ENV_FLAGS_LIST_STATIC
  2613. Enable validation of the values given to environment variables when
  2614. calling env set. Variables can be restricted to only decimal,
  2615. hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
  2616. the variables can also be restricted to IP address or MAC address.
  2617. The format of the list is:
  2618. type_attribute = [s|d|x|b|i|m]
  2619. access_attribute = [a|r|o|c]
  2620. attributes = type_attribute[access_attribute]
  2621. entry = variable_name[:attributes]
  2622. list = entry[,list]
  2623. The type attributes are:
  2624. s - String (default)
  2625. d - Decimal
  2626. x - Hexadecimal
  2627. b - Boolean ([1yYtT|0nNfF])
  2628. i - IP address
  2629. m - MAC address
  2630. The access attributes are:
  2631. a - Any (default)
  2632. r - Read-only
  2633. o - Write-once
  2634. c - Change-default
  2635. - CONFIG_ENV_FLAGS_LIST_DEFAULT
  2636. Define this to a list (string) to define the ".flags"
  2637. environment variable in the default or embedded environment.
  2638. - CONFIG_ENV_FLAGS_LIST_STATIC
  2639. Define this to a list (string) to define validation that
  2640. should be done if an entry is not found in the ".flags"
  2641. environment variable. To override a setting in the static
  2642. list, simply add an entry for the same variable name to the
  2643. ".flags" variable.
  2644. If CONFIG_REGEX is defined, the variable_name above is evaluated as a
  2645. regular expression. This allows multiple variables to define the same
  2646. flags without explicitly listing them for each variable.
  2647. - CONFIG_ENV_ACCESS_IGNORE_FORCE
  2648. If defined, don't allow the -f switch to env set override variable
  2649. access flags.
  2650. - CONFIG_USE_STDINT
  2651. If stdint.h is available with your toolchain you can define this
  2652. option to enable it. You can provide option 'USE_STDINT=1' when
  2653. building U-Boot to enable this.
  2654. The following definitions that deal with the placement and management
  2655. of environment data (variable area); in general, we support the
  2656. following configurations:
  2657. - CONFIG_BUILD_ENVCRC:
  2658. Builds up envcrc with the target environment so that external utils
  2659. may easily extract it and embed it in final U-Boot images.
  2660. - CONFIG_ENV_IS_IN_FLASH:
  2661. Define this if the environment is in flash memory.
  2662. a) The environment occupies one whole flash sector, which is
  2663. "embedded" in the text segment with the U-Boot code. This
  2664. happens usually with "bottom boot sector" or "top boot
  2665. sector" type flash chips, which have several smaller
  2666. sectors at the start or the end. For instance, such a
  2667. layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
  2668. such a case you would place the environment in one of the
  2669. 4 kB sectors - with U-Boot code before and after it. With
  2670. "top boot sector" type flash chips, you would put the
  2671. environment in one of the last sectors, leaving a gap
  2672. between U-Boot and the environment.
  2673. - CONFIG_ENV_OFFSET:
  2674. Offset of environment data (variable area) to the
  2675. beginning of flash memory; for instance, with bottom boot
  2676. type flash chips the second sector can be used: the offset
  2677. for this sector is given here.
  2678. CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
  2679. - CONFIG_ENV_ADDR:
  2680. This is just another way to specify the start address of
  2681. the flash sector containing the environment (instead of
  2682. CONFIG_ENV_OFFSET).
  2683. - CONFIG_ENV_SECT_SIZE:
  2684. Size of the sector containing the environment.
  2685. b) Sometimes flash chips have few, equal sized, BIG sectors.
  2686. In such a case you don't want to spend a whole sector for
  2687. the environment.
  2688. - CONFIG_ENV_SIZE:
  2689. If you use this in combination with CONFIG_ENV_IS_IN_FLASH
  2690. and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
  2691. of this flash sector for the environment. This saves
  2692. memory for the RAM copy of the environment.
  2693. It may also save flash memory if you decide to use this
  2694. when your environment is "embedded" within U-Boot code,
  2695. since then the remainder of the flash sector could be used
  2696. for U-Boot code. It should be pointed out that this is
  2697. STRONGLY DISCOURAGED from a robustness point of view:
  2698. updating the environment in flash makes it always
  2699. necessary to erase the WHOLE sector. If something goes
  2700. wrong before the contents has been restored from a copy in
  2701. RAM, your target system will be dead.
  2702. - CONFIG_ENV_ADDR_REDUND
  2703. CONFIG_ENV_SIZE_REDUND
  2704. These settings describe a second storage area used to hold
  2705. a redundant copy of the environment data, so that there is
  2706. a valid backup copy in case there is a power failure during
  2707. a "saveenv" operation.
  2708. BE CAREFUL! Any changes to the flash layout, and some changes to the
  2709. source code will make it necessary to adapt <board>/u-boot.lds*
  2710. accordingly!
  2711. - CONFIG_ENV_IS_IN_NVRAM:
  2712. Define this if you have some non-volatile memory device
  2713. (NVRAM, battery buffered SRAM) which you want to use for the
  2714. environment.
  2715. - CONFIG_ENV_ADDR:
  2716. - CONFIG_ENV_SIZE:
  2717. These two #defines are used to determine the memory area you
  2718. want to use for environment. It is assumed that this memory
  2719. can just be read and written to, without any special
  2720. provision.
  2721. BE CAREFUL! The first access to the environment happens quite early
  2722. in U-Boot initialization (when we try to get the setting of for the
  2723. console baudrate). You *MUST* have mapped your NVRAM area then, or
  2724. U-Boot will hang.
  2725. Please note that even with NVRAM we still use a copy of the
  2726. environment in RAM: we could work on NVRAM directly, but we want to
  2727. keep settings there always unmodified except somebody uses "saveenv"
  2728. to save the current settings.
  2729. - CONFIG_ENV_IS_IN_EEPROM:
  2730. Use this if you have an EEPROM or similar serial access
  2731. device and a driver for it.
  2732. - CONFIG_ENV_OFFSET:
  2733. - CONFIG_ENV_SIZE:
  2734. These two #defines specify the offset and size of the
  2735. environment area within the total memory of your EEPROM.
  2736. - CONFIG_SYS_I2C_EEPROM_ADDR:
  2737. If defined, specified the chip address of the EEPROM device.
  2738. The default address is zero.
  2739. - CONFIG_SYS_I2C_EEPROM_BUS:
  2740. If defined, specified the i2c bus of the EEPROM device.
  2741. - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
  2742. If defined, the number of bits used to address bytes in a
  2743. single page in the EEPROM device. A 64 byte page, for example
  2744. would require six bits.
  2745. - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
  2746. If defined, the number of milliseconds to delay between
  2747. page writes. The default is zero milliseconds.
  2748. - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
  2749. The length in bytes of the EEPROM memory array address. Note
  2750. that this is NOT the chip address length!
  2751. - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
  2752. EEPROM chips that implement "address overflow" are ones
  2753. like Catalyst 24WC04/08/16 which has 9/10/11 bits of
  2754. address and the extra bits end up in the "chip address" bit
  2755. slots. This makes a 24WC08 (1Kbyte) chip look like four 256
  2756. byte chips.
  2757. Note that we consider the length of the address field to
  2758. still be one byte because the extra address bits are hidden
  2759. in the chip address.
  2760. - CONFIG_SYS_EEPROM_SIZE:
  2761. The size in bytes of the EEPROM device.
  2762. - CONFIG_ENV_EEPROM_IS_ON_I2C
  2763. define this, if you have I2C and SPI activated, and your
  2764. EEPROM, which holds the environment, is on the I2C bus.
  2765. - CONFIG_I2C_ENV_EEPROM_BUS
  2766. if you have an Environment on an EEPROM reached over
  2767. I2C muxes, you can define here, how to reach this
  2768. EEPROM. For example:
  2769. #define CONFIG_I2C_ENV_EEPROM_BUS 1
  2770. EEPROM which holds the environment, is reached over
  2771. a pca9547 i2c mux with address 0x70, channel 3.
  2772. - CONFIG_ENV_IS_IN_DATAFLASH:
  2773. Define this if you have a DataFlash memory device which you
  2774. want to use for the environment.
  2775. - CONFIG_ENV_OFFSET:
  2776. - CONFIG_ENV_ADDR:
  2777. - CONFIG_ENV_SIZE:
  2778. These three #defines specify the offset and size of the
  2779. environment area within the total memory of your DataFlash placed
  2780. at the specified address.
  2781. - CONFIG_ENV_IS_IN_SPI_FLASH:
  2782. Define this if you have a SPI Flash memory device which you
  2783. want to use for the environment.
  2784. - CONFIG_ENV_OFFSET:
  2785. - CONFIG_ENV_SIZE:
  2786. These two #defines specify the offset and size of the
  2787. environment area within the SPI Flash. CONFIG_ENV_OFFSET must be
  2788. aligned to an erase sector boundary.
  2789. - CONFIG_ENV_SECT_SIZE:
  2790. Define the SPI flash's sector size.
  2791. - CONFIG_ENV_OFFSET_REDUND (optional):
  2792. This setting describes a second storage area of CONFIG_ENV_SIZE
  2793. size used to hold a redundant copy of the environment data, so
  2794. that there is a valid backup copy in case there is a power failure
  2795. during a "saveenv" operation. CONFIG_ENV_OFFSET_REDUND must be
  2796. aligned to an erase sector boundary.
  2797. - CONFIG_ENV_SPI_BUS (optional):
  2798. - CONFIG_ENV_SPI_CS (optional):
  2799. Define the SPI bus and chip select. If not defined they will be 0.
  2800. - CONFIG_ENV_SPI_MAX_HZ (optional):
  2801. Define the SPI max work clock. If not defined then use 1MHz.
  2802. - CONFIG_ENV_SPI_MODE (optional):
  2803. Define the SPI work mode. If not defined then use SPI_MODE_3.
  2804. - CONFIG_ENV_IS_IN_REMOTE:
  2805. Define this if you have a remote memory space which you
  2806. want to use for the local device's environment.
  2807. - CONFIG_ENV_ADDR:
  2808. - CONFIG_ENV_SIZE:
  2809. These two #defines specify the address and size of the
  2810. environment area within the remote memory space. The
  2811. local device can get the environment from remote memory
  2812. space by SRIO or PCIE links.
  2813. BE CAREFUL! For some special cases, the local device can not use
  2814. "saveenv" command. For example, the local device will get the
  2815. environment stored in a remote NOR flash by SRIO or PCIE link,
  2816. but it can not erase, write this NOR flash by SRIO or PCIE interface.
  2817. - CONFIG_ENV_IS_IN_NAND:
  2818. Define this if you have a NAND device which you want to use
  2819. for the environment.
  2820. - CONFIG_ENV_OFFSET:
  2821. - CONFIG_ENV_SIZE:
  2822. These two #defines specify the offset and size of the environment
  2823. area within the first NAND device. CONFIG_ENV_OFFSET must be
  2824. aligned to an erase block boundary.
  2825. - CONFIG_ENV_OFFSET_REDUND (optional):
  2826. This setting describes a second storage area of CONFIG_ENV_SIZE
  2827. size used to hold a redundant copy of the environment data, so
  2828. that there is a valid backup copy in case there is a power failure
  2829. during a "saveenv" operation. CONFIG_ENV_OFFSET_REDUND must be
  2830. aligned to an erase block boundary.
  2831. - CONFIG_ENV_RANGE (optional):
  2832. Specifies the length of the region in which the environment
  2833. can be written. This should be a multiple of the NAND device's
  2834. block size. Specifying a range with more erase blocks than
  2835. are needed to hold CONFIG_ENV_SIZE allows bad blocks within
  2836. the range to be avoided.
  2837. - CONFIG_ENV_OFFSET_OOB (optional):
  2838. Enables support for dynamically retrieving the offset of the
  2839. environment from block zero's out-of-band data. The
  2840. "nand env.oob" command can be used to record this offset.
  2841. Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
  2842. using CONFIG_ENV_OFFSET_OOB.
  2843. - CONFIG_NAND_ENV_DST
  2844. Defines address in RAM to which the nand_spl code should copy the
  2845. environment. If redundant environment is used, it will be copied to
  2846. CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
  2847. - CONFIG_ENV_IS_IN_UBI:
  2848. Define this if you have an UBI volume that you want to use for the
  2849. environment. This has the benefit of wear-leveling the environment
  2850. accesses, which is important on NAND.
  2851. - CONFIG_ENV_UBI_PART:
  2852. Define this to a string that is the mtd partition containing the UBI.
  2853. - CONFIG_ENV_UBI_VOLUME:
  2854. Define this to the name of the volume that you want to store the
  2855. environment in.
  2856. - CONFIG_ENV_UBI_VOLUME_REDUND:
  2857. Define this to the name of another volume to store a second copy of
  2858. the environment in. This will enable redundant environments in UBI.
  2859. It is assumed that both volumes are in the same MTD partition.
  2860. - CONFIG_UBI_SILENCE_MSG
  2861. - CONFIG_UBIFS_SILENCE_MSG
  2862. You will probably want to define these to avoid a really noisy system
  2863. when storing the env in UBI.
  2864. - CONFIG_ENV_IS_IN_FAT:
  2865. Define this if you want to use the FAT file system for the environment.
  2866. - FAT_ENV_INTERFACE:
  2867. Define this to a string that is the name of the block device.
  2868. - FAT_ENV_DEVICE_AND_PART:
  2869. Define this to a string to specify the partition of the device. It can
  2870. be as following:
  2871. "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1)
  2872. - "D:P": device D partition P. Error occurs if device D has no
  2873. partition table.
  2874. - "D:0": device D.
  2875. - "D" or "D:": device D partition 1 if device D has partition
  2876. table, or the whole device D if has no partition
  2877. table.
  2878. - "D:auto": first partition in device D with bootable flag set.
  2879. If none, first valid partition in device D. If no
  2880. partition table then means device D.
  2881. - FAT_ENV_FILE:
  2882. It's a string of the FAT file name. This file use to store the
  2883. environment.
  2884. - CONFIG_FAT_WRITE:
  2885. This must be enabled. Otherwise it cannot save the environment file.
  2886. - CONFIG_ENV_IS_IN_MMC:
  2887. Define this if you have an MMC device which you want to use for the
  2888. environment.
  2889. - CONFIG_SYS_MMC_ENV_DEV:
  2890. Specifies which MMC device the environment is stored in.
  2891. - CONFIG_SYS_MMC_ENV_PART (optional):
  2892. Specifies which MMC partition the environment is stored in. If not
  2893. set, defaults to partition 0, the user area. Common values might be
  2894. 1 (first MMC boot partition), 2 (second MMC boot partition).
  2895. - CONFIG_ENV_OFFSET:
  2896. - CONFIG_ENV_SIZE:
  2897. These two #defines specify the offset and size of the environment
  2898. area within the specified MMC device.
  2899. If offset is positive (the usual case), it is treated as relative to
  2900. the start of the MMC partition. If offset is negative, it is treated
  2901. as relative to the end of the MMC partition. This can be useful if
  2902. your board may be fitted with different MMC devices, which have
  2903. different sizes for the MMC partitions, and you always want the
  2904. environment placed at the very end of the partition, to leave the
  2905. maximum possible space before it, to store other data.
  2906. These two values are in units of bytes, but must be aligned to an
  2907. MMC sector boundary.
  2908. - CONFIG_ENV_OFFSET_REDUND (optional):
  2909. Specifies a second storage area, of CONFIG_ENV_SIZE size, used to
  2910. hold a redundant copy of the environment data. This provides a
  2911. valid backup copy in case the other copy is corrupted, e.g. due
  2912. to a power failure during a "saveenv" operation.
  2913. This value may also be positive or negative; this is handled in the
  2914. same way as CONFIG_ENV_OFFSET.
  2915. This value is also in units of bytes, but must also be aligned to
  2916. an MMC sector boundary.
  2917. - CONFIG_ENV_SIZE_REDUND (optional):
  2918. This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is
  2919. set. If this value is set, it must be set to the same value as
  2920. CONFIG_ENV_SIZE.
  2921. Please note that the environment is read-only until the monitor
  2922. has been relocated to RAM and a RAM copy of the environment has been
  2923. created; also, when using EEPROM you will have to use getenv_f()
  2924. until then to read environment variables.
  2925. The environment is protected by a CRC32 checksum. Before the monitor
  2926. is relocated into RAM, as a result of a bad CRC you will be working
  2927. with the compiled-in default environment - *silently*!!! [This is
  2928. necessary, because the first environment variable we need is the
  2929. "baudrate" setting for the console - if we have a bad CRC, we don't
  2930. have any device yet where we could complain.]
  2931. Note: once the monitor has been relocated, then it will complain if
  2932. the default environment is used; a new CRC is computed as soon as you
  2933. use the "saveenv" command to store a valid environment.
  2934. - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
  2935. Echo the inverted Ethernet link state to the fault LED.
  2936. Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
  2937. also needs to be defined.
  2938. - CONFIG_SYS_FAULT_MII_ADDR:
  2939. MII address of the PHY to check for the Ethernet link state.
  2940. - CONFIG_NS16550_MIN_FUNCTIONS:
  2941. Define this if you desire to only have use of the NS16550_init
  2942. and NS16550_putc functions for the serial driver located at
  2943. drivers/serial/ns16550.c. This option is useful for saving
  2944. space for already greatly restricted images, including but not
  2945. limited to NAND_SPL configurations.
  2946. - CONFIG_DISPLAY_BOARDINFO
  2947. Display information about the board that U-Boot is running on
  2948. when U-Boot starts up. The board function checkboard() is called
  2949. to do this.
  2950. - CONFIG_DISPLAY_BOARDINFO_LATE
  2951. Similar to the previous option, but display this information
  2952. later, once stdio is running and output goes to the LCD, if
  2953. present.
  2954. - CONFIG_BOARD_SIZE_LIMIT:
  2955. Maximum size of the U-Boot image. When defined, the
  2956. build system checks that the actual size does not
  2957. exceed it.
  2958. Low Level (hardware related) configuration options:
  2959. ---------------------------------------------------
  2960. - CONFIG_SYS_CACHELINE_SIZE:
  2961. Cache Line Size of the CPU.
  2962. - CONFIG_SYS_CCSRBAR_DEFAULT:
  2963. Default (power-on reset) physical address of CCSR on Freescale
  2964. PowerPC SOCs.
  2965. - CONFIG_SYS_CCSRBAR:
  2966. Virtual address of CCSR. On a 32-bit build, this is typically
  2967. the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
  2968. - CONFIG_SYS_CCSRBAR_PHYS:
  2969. Physical address of CCSR. CCSR can be relocated to a new
  2970. physical address, if desired. In this case, this macro should
  2971. be set to that address. Otherwise, it should be set to the
  2972. same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
  2973. is typically relocated on 36-bit builds. It is recommended
  2974. that this macro be defined via the _HIGH and _LOW macros:
  2975. #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
  2976. * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
  2977. - CONFIG_SYS_CCSRBAR_PHYS_HIGH:
  2978. Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
  2979. either 0 (32-bit build) or 0xF (36-bit build). This macro is
  2980. used in assembly code, so it must not contain typecasts or
  2981. integer size suffixes (e.g. "ULL").
  2982. - CONFIG_SYS_CCSRBAR_PHYS_LOW:
  2983. Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
  2984. used in assembly code, so it must not contain typecasts or
  2985. integer size suffixes (e.g. "ULL").
  2986. - CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
  2987. If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
  2988. forced to a value that ensures that CCSR is not relocated.
  2989. - Floppy Disk Support:
  2990. CONFIG_SYS_FDC_DRIVE_NUMBER
  2991. the default drive number (default value 0)
  2992. CONFIG_SYS_ISA_IO_STRIDE
  2993. defines the spacing between FDC chipset registers
  2994. (default value 1)
  2995. CONFIG_SYS_ISA_IO_OFFSET
  2996. defines the offset of register from address. It
  2997. depends on which part of the data bus is connected to
  2998. the FDC chipset. (default value 0)
  2999. If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
  3000. CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
  3001. default value.
  3002. if CONFIG_SYS_FDC_HW_INIT is defined, then the function
  3003. fdc_hw_init() is called at the beginning of the FDC
  3004. setup. fdc_hw_init() must be provided by the board
  3005. source code. It is used to make hardware-dependent
  3006. initializations.
  3007. - CONFIG_IDE_AHB:
  3008. Most IDE controllers were designed to be connected with PCI
  3009. interface. Only few of them were designed for AHB interface.
  3010. When software is doing ATA command and data transfer to
  3011. IDE devices through IDE-AHB controller, some additional
  3012. registers accessing to these kind of IDE-AHB controller
  3013. is required.
  3014. - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
  3015. DO NOT CHANGE unless you know exactly what you're
  3016. doing! (11-4) [82xx systems only]
  3017. - CONFIG_SYS_INIT_RAM_ADDR:
  3018. Start address of memory area that can be used for
  3019. initial data and stack; please note that this must be
  3020. writable memory that is working WITHOUT special
  3021. initialization, i. e. you CANNOT use normal RAM which
  3022. will become available only after programming the
  3023. memory controller and running certain initialization
  3024. sequences.
  3025. U-Boot uses the following memory types:
  3026. - CONFIG_SYS_GBL_DATA_OFFSET:
  3027. Offset of the initial data structure in the memory
  3028. area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
  3029. CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
  3030. data is located at the end of the available space
  3031. (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
  3032. GENERATED_GBL_DATA_SIZE), and the initial stack is just
  3033. below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
  3034. CONFIG_SYS_GBL_DATA_OFFSET) downward.
  3035. Note:
  3036. On the MPC824X (or other systems that use the data
  3037. cache for initial memory) the address chosen for
  3038. CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
  3039. point to an otherwise UNUSED address space between
  3040. the top of RAM and the start of the PCI space.
  3041. - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
  3042. - CONFIG_SYS_OR_TIMING_SDRAM:
  3043. SDRAM timing
  3044. - CONFIG_SYS_MAMR_PTA:
  3045. periodic timer for refresh
  3046. - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
  3047. CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
  3048. CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
  3049. CONFIG_SYS_BR1_PRELIM:
  3050. Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
  3051. - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
  3052. CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
  3053. CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
  3054. Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
  3055. - CONFIG_PCI_ENUM_ONLY
  3056. Only scan through and get the devices on the buses.
  3057. Don't do any setup work, presumably because someone or
  3058. something has already done it, and we don't need to do it
  3059. a second time. Useful for platforms that are pre-booted
  3060. by coreboot or similar.
  3061. - CONFIG_PCI_INDIRECT_BRIDGE:
  3062. Enable support for indirect PCI bridges.
  3063. - CONFIG_SYS_SRIO:
  3064. Chip has SRIO or not
  3065. - CONFIG_SRIO1:
  3066. Board has SRIO 1 port available
  3067. - CONFIG_SRIO2:
  3068. Board has SRIO 2 port available
  3069. - CONFIG_SRIO_PCIE_BOOT_MASTER
  3070. Board can support master function for Boot from SRIO and PCIE
  3071. - CONFIG_SYS_SRIOn_MEM_VIRT:
  3072. Virtual Address of SRIO port 'n' memory region
  3073. - CONFIG_SYS_SRIOn_MEM_PHYS:
  3074. Physical Address of SRIO port 'n' memory region
  3075. - CONFIG_SYS_SRIOn_MEM_SIZE:
  3076. Size of SRIO port 'n' memory region
  3077. - CONFIG_SYS_NAND_BUSWIDTH_16BIT
  3078. Defined to tell the NAND controller that the NAND chip is using
  3079. a 16 bit bus.
  3080. Not all NAND drivers use this symbol.
  3081. Example of drivers that use it:
  3082. - drivers/mtd/nand/ndfc.c
  3083. - drivers/mtd/nand/mxc_nand.c
  3084. - CONFIG_SYS_NDFC_EBC0_CFG
  3085. Sets the EBC0_CFG register for the NDFC. If not defined
  3086. a default value will be used.
  3087. - CONFIG_SPD_EEPROM
  3088. Get DDR timing information from an I2C EEPROM. Common
  3089. with pluggable memory modules such as SODIMMs
  3090. SPD_EEPROM_ADDRESS
  3091. I2C address of the SPD EEPROM
  3092. - CONFIG_SYS_SPD_BUS_NUM
  3093. If SPD EEPROM is on an I2C bus other than the first
  3094. one, specify here. Note that the value must resolve
  3095. to something your driver can deal with.
  3096. - CONFIG_SYS_DDR_RAW_TIMING
  3097. Get DDR timing information from other than SPD. Common with
  3098. soldered DDR chips onboard without SPD. DDR raw timing
  3099. parameters are extracted from datasheet and hard-coded into
  3100. header files or board specific files.
  3101. - CONFIG_FSL_DDR_INTERACTIVE
  3102. Enable interactive DDR debugging. See doc/README.fsl-ddr.
  3103. - CONFIG_FSL_DDR_SYNC_REFRESH
  3104. Enable sync of refresh for multiple controllers.
  3105. - CONFIG_FSL_DDR_BIST
  3106. Enable built-in memory test for Freescale DDR controllers.
  3107. - CONFIG_SYS_83XX_DDR_USES_CS0
  3108. Only for 83xx systems. If specified, then DDR should
  3109. be configured using CS0 and CS1 instead of CS2 and CS3.
  3110. - CONFIG_RMII
  3111. Enable RMII mode for all FECs.
  3112. Note that this is a global option, we can't
  3113. have one FEC in standard MII mode and another in RMII mode.
  3114. - CONFIG_CRC32_VERIFY
  3115. Add a verify option to the crc32 command.
  3116. The syntax is:
  3117. => crc32 -v <address> <count> <crc32>
  3118. Where address/count indicate a memory area
  3119. and crc32 is the correct crc32 which the
  3120. area should have.
  3121. - CONFIG_LOOPW
  3122. Add the "loopw" memory command. This only takes effect if
  3123. the memory commands are activated globally (CONFIG_CMD_MEM).
  3124. - CONFIG_MX_CYCLIC
  3125. Add the "mdc" and "mwc" memory commands. These are cyclic
  3126. "md/mw" commands.
  3127. Examples:
  3128. => mdc.b 10 4 500
  3129. This command will print 4 bytes (10,11,12,13) each 500 ms.
  3130. => mwc.l 100 12345678 10
  3131. This command will write 12345678 to address 100 all 10 ms.
  3132. This only takes effect if the memory commands are activated
  3133. globally (CONFIG_CMD_MEM).
  3134. - CONFIG_SKIP_LOWLEVEL_INIT
  3135. [ARM, NDS32, MIPS only] If this variable is defined, then certain
  3136. low level initializations (like setting up the memory
  3137. controller) are omitted and/or U-Boot does not
  3138. relocate itself into RAM.
  3139. Normally this variable MUST NOT be defined. The only
  3140. exception is when U-Boot is loaded (to RAM) by some
  3141. other boot loader or by a debugger which performs
  3142. these initializations itself.
  3143. - CONFIG_SKIP_LOWLEVEL_INIT_ONLY
  3144. [ARM926EJ-S only] This allows just the call to lowlevel_init()
  3145. to be skipped. The normal CP15 init (such as enabling the
  3146. instruction cache) is still performed.
  3147. - CONFIG_SPL_BUILD
  3148. Modifies the behaviour of start.S when compiling a loader
  3149. that is executed before the actual U-Boot. E.g. when
  3150. compiling a NAND SPL.
  3151. - CONFIG_TPL_BUILD
  3152. Modifies the behaviour of start.S when compiling a loader
  3153. that is executed after the SPL and before the actual U-Boot.
  3154. It is loaded by the SPL.
  3155. - CONFIG_SYS_MPC85XX_NO_RESETVEC
  3156. Only for 85xx systems. If this variable is specified, the section
  3157. .resetvec is not kept and the section .bootpg is placed in the
  3158. previous 4k of the .text section.
  3159. - CONFIG_ARCH_MAP_SYSMEM
  3160. Generally U-Boot (and in particular the md command) uses
  3161. effective address. It is therefore not necessary to regard
  3162. U-Boot address as virtual addresses that need to be translated
  3163. to physical addresses. However, sandbox requires this, since
  3164. it maintains its own little RAM buffer which contains all
  3165. addressable memory. This option causes some memory accesses
  3166. to be mapped through map_sysmem() / unmap_sysmem().
  3167. - CONFIG_X86_RESET_VECTOR
  3168. If defined, the x86 reset vector code is included. This is not
  3169. needed when U-Boot is running from Coreboot.
  3170. - CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC:
  3171. Enables the RTC32K OSC on AM33xx based plattforms
  3172. - CONFIG_SYS_NAND_NO_SUBPAGE_WRITE
  3173. Option to disable subpage write in NAND driver
  3174. driver that uses this:
  3175. drivers/mtd/nand/davinci_nand.c
  3176. Freescale QE/FMAN Firmware Support:
  3177. -----------------------------------
  3178. The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
  3179. loading of "firmware", which is encoded in the QE firmware binary format.
  3180. This firmware often needs to be loaded during U-Boot booting, so macros
  3181. are used to identify the storage device (NOR flash, SPI, etc) and the address
  3182. within that device.
  3183. - CONFIG_SYS_FMAN_FW_ADDR
  3184. The address in the storage device where the FMAN microcode is located. The
  3185. meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
  3186. is also specified.
  3187. - CONFIG_SYS_QE_FW_ADDR
  3188. The address in the storage device where the QE microcode is located. The
  3189. meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
  3190. is also specified.
  3191. - CONFIG_SYS_QE_FMAN_FW_LENGTH
  3192. The maximum possible size of the firmware. The firmware binary format
  3193. has a field that specifies the actual size of the firmware, but it
  3194. might not be possible to read any part of the firmware unless some
  3195. local storage is allocated to hold the entire firmware first.
  3196. - CONFIG_SYS_QE_FMAN_FW_IN_NOR
  3197. Specifies that QE/FMAN firmware is located in NOR flash, mapped as
  3198. normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
  3199. virtual address in NOR flash.
  3200. - CONFIG_SYS_QE_FMAN_FW_IN_NAND
  3201. Specifies that QE/FMAN firmware is located in NAND flash.
  3202. CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
  3203. - CONFIG_SYS_QE_FMAN_FW_IN_MMC
  3204. Specifies that QE/FMAN firmware is located on the primary SD/MMC
  3205. device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
  3206. - CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
  3207. Specifies that QE/FMAN firmware is located in the remote (master)
  3208. memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
  3209. can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
  3210. window->master inbound window->master LAW->the ucode address in
  3211. master's memory space.
  3212. Freescale Layerscape Management Complex Firmware Support:
  3213. ---------------------------------------------------------
  3214. The Freescale Layerscape Management Complex (MC) supports the loading of
  3215. "firmware".
  3216. This firmware often needs to be loaded during U-Boot booting, so macros
  3217. are used to identify the storage device (NOR flash, SPI, etc) and the address
  3218. within that device.
  3219. - CONFIG_FSL_MC_ENET
  3220. Enable the MC driver for Layerscape SoCs.
  3221. Freescale Layerscape Debug Server Support:
  3222. -------------------------------------------
  3223. The Freescale Layerscape Debug Server Support supports the loading of
  3224. "Debug Server firmware" and triggering SP boot-rom.
  3225. This firmware often needs to be loaded during U-Boot booting.
  3226. - CONFIG_SYS_MC_RSV_MEM_ALIGN
  3227. Define alignment of reserved memory MC requires
  3228. Reproducible builds
  3229. -------------------
  3230. In order to achieve reproducible builds, timestamps used in the U-Boot build
  3231. process have to be set to a fixed value.
  3232. This is done using the SOURCE_DATE_EPOCH environment variable.
  3233. SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration
  3234. option for U-Boot or an environment variable in U-Boot.
  3235. SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC.
  3236. Building the Software:
  3237. ======================
  3238. Building U-Boot has been tested in several native build environments
  3239. and in many different cross environments. Of course we cannot support
  3240. all possibly existing versions of cross development tools in all
  3241. (potentially obsolete) versions. In case of tool chain problems we
  3242. recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
  3243. which is extensively used to build and test U-Boot.
  3244. If you are not using a native environment, it is assumed that you
  3245. have GNU cross compiling tools available in your path. In this case,
  3246. you must set the environment variable CROSS_COMPILE in your shell.
  3247. Note that no changes to the Makefile or any other source files are
  3248. necessary. For example using the ELDK on a 4xx CPU, please enter:
  3249. $ CROSS_COMPILE=ppc_4xx-
  3250. $ export CROSS_COMPILE
  3251. Note: If you wish to generate Windows versions of the utilities in
  3252. the tools directory you can use the MinGW toolchain
  3253. (http://www.mingw.org). Set your HOST tools to the MinGW
  3254. toolchain and execute 'make tools'. For example:
  3255. $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
  3256. Binaries such as tools/mkimage.exe will be created which can
  3257. be executed on computers running Windows.
  3258. U-Boot is intended to be simple to build. After installing the
  3259. sources you must configure U-Boot for one specific board type. This
  3260. is done by typing:
  3261. make NAME_defconfig
  3262. where "NAME_defconfig" is the name of one of the existing configu-
  3263. rations; see boards.cfg for supported names.
  3264. Note: for some board special configuration names may exist; check if
  3265. additional information is available from the board vendor; for
  3266. instance, the TQM823L systems are available without (standard)
  3267. or with LCD support. You can select such additional "features"
  3268. when choosing the configuration, i. e.
  3269. make TQM823L_defconfig
  3270. - will configure for a plain TQM823L, i. e. no LCD support
  3271. make TQM823L_LCD_defconfig
  3272. - will configure for a TQM823L with U-Boot console on LCD
  3273. etc.
  3274. Finally, type "make all", and you should get some working U-Boot
  3275. images ready for download to / installation on your system:
  3276. - "u-boot.bin" is a raw binary image
  3277. - "u-boot" is an image in ELF binary format
  3278. - "u-boot.srec" is in Motorola S-Record format
  3279. By default the build is performed locally and the objects are saved
  3280. in the source directory. One of the two methods can be used to change
  3281. this behavior and build U-Boot to some external directory:
  3282. 1. Add O= to the make command line invocations:
  3283. make O=/tmp/build distclean
  3284. make O=/tmp/build NAME_defconfig
  3285. make O=/tmp/build all
  3286. 2. Set environment variable KBUILD_OUTPUT to point to the desired location:
  3287. export KBUILD_OUTPUT=/tmp/build
  3288. make distclean
  3289. make NAME_defconfig
  3290. make all
  3291. Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment
  3292. variable.
  3293. Please be aware that the Makefiles assume you are using GNU make, so
  3294. for instance on NetBSD you might need to use "gmake" instead of
  3295. native "make".
  3296. If the system board that you have is not listed, then you will need
  3297. to port U-Boot to your hardware platform. To do this, follow these
  3298. steps:
  3299. 1. Create a new directory to hold your board specific code. Add any
  3300. files you need. In your board directory, you will need at least
  3301. the "Makefile" and a "<board>.c".
  3302. 2. Create a new configuration file "include/configs/<board>.h" for
  3303. your board.
  3304. 3. If you're porting U-Boot to a new CPU, then also create a new
  3305. directory to hold your CPU specific code. Add any files you need.
  3306. 4. Run "make <board>_defconfig" with your new name.
  3307. 5. Type "make", and you should get a working "u-boot.srec" file
  3308. to be installed on your target system.
  3309. 6. Debug and solve any problems that might arise.
  3310. [Of course, this last step is much harder than it sounds.]
  3311. Testing of U-Boot Modifications, Ports to New Hardware, etc.:
  3312. ==============================================================
  3313. If you have modified U-Boot sources (for instance added a new board
  3314. or support for new devices, a new CPU, etc.) you are expected to
  3315. provide feedback to the other developers. The feedback normally takes
  3316. the form of a "patch", i. e. a context diff against a certain (latest
  3317. official or latest in the git repository) version of U-Boot sources.
  3318. But before you submit such a patch, please verify that your modifi-
  3319. cation did not break existing code. At least make sure that *ALL* of
  3320. the supported boards compile WITHOUT ANY compiler warnings. To do so,
  3321. just run the buildman script (tools/buildman/buildman), which will
  3322. configure and build U-Boot for ALL supported system. Be warned, this
  3323. will take a while. Please see the buildman README, or run 'buildman -H'
  3324. for documentation.
  3325. See also "U-Boot Porting Guide" below.
  3326. Monitor Commands - Overview:
  3327. ============================
  3328. go - start application at address 'addr'
  3329. run - run commands in an environment variable
  3330. bootm - boot application image from memory
  3331. bootp - boot image via network using BootP/TFTP protocol
  3332. bootz - boot zImage from memory
  3333. tftpboot- boot image via network using TFTP protocol
  3334. and env variables "ipaddr" and "serverip"
  3335. (and eventually "gatewayip")
  3336. tftpput - upload a file via network using TFTP protocol
  3337. rarpboot- boot image via network using RARP/TFTP protocol
  3338. diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
  3339. loads - load S-Record file over serial line
  3340. loadb - load binary file over serial line (kermit mode)
  3341. md - memory display
  3342. mm - memory modify (auto-incrementing)
  3343. nm - memory modify (constant address)
  3344. mw - memory write (fill)
  3345. cp - memory copy
  3346. cmp - memory compare
  3347. crc32 - checksum calculation
  3348. i2c - I2C sub-system
  3349. sspi - SPI utility commands
  3350. base - print or set address offset
  3351. printenv- print environment variables
  3352. setenv - set environment variables
  3353. saveenv - save environment variables to persistent storage
  3354. protect - enable or disable FLASH write protection
  3355. erase - erase FLASH memory
  3356. flinfo - print FLASH memory information
  3357. nand - NAND memory operations (see doc/README.nand)
  3358. bdinfo - print Board Info structure
  3359. iminfo - print header information for application image
  3360. coninfo - print console devices and informations
  3361. ide - IDE sub-system
  3362. loop - infinite loop on address range
  3363. loopw - infinite write loop on address range
  3364. mtest - simple RAM test
  3365. icache - enable or disable instruction cache
  3366. dcache - enable or disable data cache
  3367. reset - Perform RESET of the CPU
  3368. echo - echo args to console
  3369. version - print monitor version
  3370. help - print online help
  3371. ? - alias for 'help'
  3372. Monitor Commands - Detailed Description:
  3373. ========================================
  3374. TODO.
  3375. For now: just type "help <command>".
  3376. Environment Variables:
  3377. ======================
  3378. U-Boot supports user configuration using Environment Variables which
  3379. can be made persistent by saving to Flash memory.
  3380. Environment Variables are set using "setenv", printed using
  3381. "printenv", and saved to Flash using "saveenv". Using "setenv"
  3382. without a value can be used to delete a variable from the
  3383. environment. As long as you don't save the environment you are
  3384. working with an in-memory copy. In case the Flash area containing the
  3385. environment is erased by accident, a default environment is provided.
  3386. Some configuration options can be set using Environment Variables.
  3387. List of environment variables (most likely not complete):
  3388. baudrate - see CONFIG_BAUDRATE
  3389. bootdelay - see CONFIG_BOOTDELAY
  3390. bootcmd - see CONFIG_BOOTCOMMAND
  3391. bootargs - Boot arguments when booting an RTOS image
  3392. bootfile - Name of the image to load with TFTP
  3393. bootm_low - Memory range available for image processing in the bootm
  3394. command can be restricted. This variable is given as
  3395. a hexadecimal number and defines lowest address allowed
  3396. for use by the bootm command. See also "bootm_size"
  3397. environment variable. Address defined by "bootm_low" is
  3398. also the base of the initial memory mapping for the Linux
  3399. kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
  3400. bootm_mapsize.
  3401. bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
  3402. This variable is given as a hexadecimal number and it
  3403. defines the size of the memory region starting at base
  3404. address bootm_low that is accessible by the Linux kernel
  3405. during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
  3406. as the default value if it is defined, and bootm_size is
  3407. used otherwise.
  3408. bootm_size - Memory range available for image processing in the bootm
  3409. command can be restricted. This variable is given as
  3410. a hexadecimal number and defines the size of the region
  3411. allowed for use by the bootm command. See also "bootm_low"
  3412. environment variable.
  3413. updatefile - Location of the software update file on a TFTP server, used
  3414. by the automatic software update feature. Please refer to
  3415. documentation in doc/README.update for more details.
  3416. autoload - if set to "no" (any string beginning with 'n'),
  3417. "bootp" will just load perform a lookup of the
  3418. configuration from the BOOTP server, but not try to
  3419. load any image using TFTP
  3420. autostart - if set to "yes", an image loaded using the "bootp",
  3421. "rarpboot", "tftpboot" or "diskboot" commands will
  3422. be automatically started (by internally calling
  3423. "bootm")
  3424. If set to "no", a standalone image passed to the
  3425. "bootm" command will be copied to the load address
  3426. (and eventually uncompressed), but NOT be started.
  3427. This can be used to load and uncompress arbitrary
  3428. data.
  3429. fdt_high - if set this restricts the maximum address that the
  3430. flattened device tree will be copied into upon boot.
  3431. For example, if you have a system with 1 GB memory
  3432. at physical address 0x10000000, while Linux kernel
  3433. only recognizes the first 704 MB as low memory, you
  3434. may need to set fdt_high as 0x3C000000 to have the
  3435. device tree blob be copied to the maximum address
  3436. of the 704 MB low memory, so that Linux kernel can
  3437. access it during the boot procedure.
  3438. If this is set to the special value 0xFFFFFFFF then
  3439. the fdt will not be copied at all on boot. For this
  3440. to work it must reside in writable memory, have
  3441. sufficient padding on the end of it for u-boot to
  3442. add the information it needs into it, and the memory
  3443. must be accessible by the kernel.
  3444. fdtcontroladdr- if set this is the address of the control flattened
  3445. device tree used by U-Boot when CONFIG_OF_CONTROL is
  3446. defined.
  3447. i2cfast - (PPC405GP|PPC405EP only)
  3448. if set to 'y' configures Linux I2C driver for fast
  3449. mode (400kHZ). This environment variable is used in
  3450. initialization code. So, for changes to be effective
  3451. it must be saved and board must be reset.
  3452. initrd_high - restrict positioning of initrd images:
  3453. If this variable is not set, initrd images will be
  3454. copied to the highest possible address in RAM; this
  3455. is usually what you want since it allows for
  3456. maximum initrd size. If for some reason you want to
  3457. make sure that the initrd image is loaded below the
  3458. CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
  3459. variable to a value of "no" or "off" or "0".
  3460. Alternatively, you can set it to a maximum upper
  3461. address to use (U-Boot will still check that it
  3462. does not overwrite the U-Boot stack and data).
  3463. For instance, when you have a system with 16 MB
  3464. RAM, and want to reserve 4 MB from use by Linux,
  3465. you can do this by adding "mem=12M" to the value of
  3466. the "bootargs" variable. However, now you must make
  3467. sure that the initrd image is placed in the first
  3468. 12 MB as well - this can be done with
  3469. setenv initrd_high 00c00000
  3470. If you set initrd_high to 0xFFFFFFFF, this is an
  3471. indication to U-Boot that all addresses are legal
  3472. for the Linux kernel, including addresses in flash
  3473. memory. In this case U-Boot will NOT COPY the
  3474. ramdisk at all. This may be useful to reduce the
  3475. boot time on your system, but requires that this
  3476. feature is supported by your Linux kernel.
  3477. ipaddr - IP address; needed for tftpboot command
  3478. loadaddr - Default load address for commands like "bootp",
  3479. "rarpboot", "tftpboot", "loadb" or "diskboot"
  3480. loads_echo - see CONFIG_LOADS_ECHO
  3481. serverip - TFTP server IP address; needed for tftpboot command
  3482. bootretry - see CONFIG_BOOT_RETRY_TIME
  3483. bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
  3484. bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
  3485. ethprime - controls which interface is used first.
  3486. ethact - controls which interface is currently active.
  3487. For example you can do the following
  3488. => setenv ethact FEC
  3489. => ping 192.168.0.1 # traffic sent on FEC
  3490. => setenv ethact SCC
  3491. => ping 10.0.0.1 # traffic sent on SCC
  3492. ethrotate - When set to "no" U-Boot does not go through all
  3493. available network interfaces.
  3494. It just stays at the currently selected interface.
  3495. netretry - When set to "no" each network operation will
  3496. either succeed or fail without retrying.
  3497. When set to "once" the network operation will
  3498. fail when all the available network interfaces
  3499. are tried once without success.
  3500. Useful on scripts which control the retry operation
  3501. themselves.
  3502. npe_ucode - set load address for the NPE microcode
  3503. silent_linux - If set then Linux will be told to boot silently, by
  3504. changing the console to be empty. If "yes" it will be
  3505. made silent. If "no" it will not be made silent. If
  3506. unset, then it will be made silent if the U-Boot console
  3507. is silent.
  3508. tftpsrcp - If this is set, the value is used for TFTP's
  3509. UDP source port.
  3510. tftpdstp - If this is set, the value is used for TFTP's UDP
  3511. destination port instead of the Well Know Port 69.
  3512. tftpblocksize - Block size to use for TFTP transfers; if not set,
  3513. we use the TFTP server's default block size
  3514. tftptimeout - Retransmission timeout for TFTP packets (in milli-
  3515. seconds, minimum value is 1000 = 1 second). Defines
  3516. when a packet is considered to be lost so it has to
  3517. be retransmitted. The default is 5000 = 5 seconds.
  3518. Lowering this value may make downloads succeed
  3519. faster in networks with high packet loss rates or
  3520. with unreliable TFTP servers.
  3521. tftptimeoutcountmax - maximum count of TFTP timeouts (no
  3522. unit, minimum value = 0). Defines how many timeouts
  3523. can happen during a single file transfer before that
  3524. transfer is aborted. The default is 10, and 0 means
  3525. 'no timeouts allowed'. Increasing this value may help
  3526. downloads succeed with high packet loss rates, or with
  3527. unreliable TFTP servers or client hardware.
  3528. vlan - When set to a value < 4095 the traffic over
  3529. Ethernet is encapsulated/received over 802.1q
  3530. VLAN tagged frames.
  3531. bootpretryperiod - Period during which BOOTP/DHCP sends retries.
  3532. Unsigned value, in milliseconds. If not set, the period will
  3533. be either the default (28000), or a value based on
  3534. CONFIG_NET_RETRY_COUNT, if defined. This value has
  3535. precedence over the valu based on CONFIG_NET_RETRY_COUNT.
  3536. The following image location variables contain the location of images
  3537. used in booting. The "Image" column gives the role of the image and is
  3538. not an environment variable name. The other columns are environment
  3539. variable names. "File Name" gives the name of the file on a TFTP
  3540. server, "RAM Address" gives the location in RAM the image will be
  3541. loaded to, and "Flash Location" gives the image's address in NOR
  3542. flash or offset in NAND flash.
  3543. *Note* - these variables don't have to be defined for all boards, some
  3544. boards currently use other variables for these purposes, and some
  3545. boards use these variables for other purposes.
  3546. Image File Name RAM Address Flash Location
  3547. ----- --------- ----------- --------------
  3548. u-boot u-boot u-boot_addr_r u-boot_addr
  3549. Linux kernel bootfile kernel_addr_r kernel_addr
  3550. device tree blob fdtfile fdt_addr_r fdt_addr
  3551. ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
  3552. The following environment variables may be used and automatically
  3553. updated by the network boot commands ("bootp" and "rarpboot"),
  3554. depending the information provided by your boot server:
  3555. bootfile - see above
  3556. dnsip - IP address of your Domain Name Server
  3557. dnsip2 - IP address of your secondary Domain Name Server
  3558. gatewayip - IP address of the Gateway (Router) to use
  3559. hostname - Target hostname
  3560. ipaddr - see above
  3561. netmask - Subnet Mask
  3562. rootpath - Pathname of the root filesystem on the NFS server
  3563. serverip - see above
  3564. There are two special Environment Variables:
  3565. serial# - contains hardware identification information such
  3566. as type string and/or serial number
  3567. ethaddr - Ethernet address
  3568. These variables can be set only once (usually during manufacturing of
  3569. the board). U-Boot refuses to delete or overwrite these variables
  3570. once they have been set once.
  3571. Further special Environment Variables:
  3572. ver - Contains the U-Boot version string as printed
  3573. with the "version" command. This variable is
  3574. readonly (see CONFIG_VERSION_VARIABLE).
  3575. Please note that changes to some configuration parameters may take
  3576. only effect after the next boot (yes, that's just like Windoze :-).
  3577. Callback functions for environment variables:
  3578. ---------------------------------------------
  3579. For some environment variables, the behavior of u-boot needs to change
  3580. when their values are changed. This functionality allows functions to
  3581. be associated with arbitrary variables. On creation, overwrite, or
  3582. deletion, the callback will provide the opportunity for some side
  3583. effect to happen or for the change to be rejected.
  3584. The callbacks are named and associated with a function using the
  3585. U_BOOT_ENV_CALLBACK macro in your board or driver code.
  3586. These callbacks are associated with variables in one of two ways. The
  3587. static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
  3588. in the board configuration to a string that defines a list of
  3589. associations. The list must be in the following format:
  3590. entry = variable_name[:callback_name]
  3591. list = entry[,list]
  3592. If the callback name is not specified, then the callback is deleted.
  3593. Spaces are also allowed anywhere in the list.
  3594. Callbacks can also be associated by defining the ".callbacks" variable
  3595. with the same list format above. Any association in ".callbacks" will
  3596. override any association in the static list. You can define
  3597. CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
  3598. ".callbacks" environment variable in the default or embedded environment.
  3599. If CONFIG_REGEX is defined, the variable_name above is evaluated as a
  3600. regular expression. This allows multiple variables to be connected to
  3601. the same callback without explicitly listing them all out.
  3602. Command Line Parsing:
  3603. =====================
  3604. There are two different command line parsers available with U-Boot:
  3605. the old "simple" one, and the much more powerful "hush" shell:
  3606. Old, simple command line parser:
  3607. --------------------------------
  3608. - supports environment variables (through setenv / saveenv commands)
  3609. - several commands on one line, separated by ';'
  3610. - variable substitution using "... ${name} ..." syntax
  3611. - special characters ('$', ';') can be escaped by prefixing with '\',
  3612. for example:
  3613. setenv bootcmd bootm \${address}
  3614. - You can also escape text by enclosing in single apostrophes, for example:
  3615. setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
  3616. Hush shell:
  3617. -----------
  3618. - similar to Bourne shell, with control structures like
  3619. if...then...else...fi, for...do...done; while...do...done,
  3620. until...do...done, ...
  3621. - supports environment ("global") variables (through setenv / saveenv
  3622. commands) and local shell variables (through standard shell syntax
  3623. "name=value"); only environment variables can be used with "run"
  3624. command
  3625. General rules:
  3626. --------------
  3627. (1) If a command line (or an environment variable executed by a "run"
  3628. command) contains several commands separated by semicolon, and
  3629. one of these commands fails, then the remaining commands will be
  3630. executed anyway.
  3631. (2) If you execute several variables with one call to run (i. e.
  3632. calling run with a list of variables as arguments), any failing
  3633. command will cause "run" to terminate, i. e. the remaining
  3634. variables are not executed.
  3635. Note for Redundant Ethernet Interfaces:
  3636. =======================================
  3637. Some boards come with redundant Ethernet interfaces; U-Boot supports
  3638. such configurations and is capable of automatic selection of a
  3639. "working" interface when needed. MAC assignment works as follows:
  3640. Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
  3641. MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
  3642. "eth1addr" (=>eth1), "eth2addr", ...
  3643. If the network interface stores some valid MAC address (for instance
  3644. in SROM), this is used as default address if there is NO correspon-
  3645. ding setting in the environment; if the corresponding environment
  3646. variable is set, this overrides the settings in the card; that means:
  3647. o If the SROM has a valid MAC address, and there is no address in the
  3648. environment, the SROM's address is used.
  3649. o If there is no valid address in the SROM, and a definition in the
  3650. environment exists, then the value from the environment variable is
  3651. used.
  3652. o If both the SROM and the environment contain a MAC address, and
  3653. both addresses are the same, this MAC address is used.
  3654. o If both the SROM and the environment contain a MAC address, and the
  3655. addresses differ, the value from the environment is used and a
  3656. warning is printed.
  3657. o If neither SROM nor the environment contain a MAC address, an error
  3658. is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case
  3659. a random, locally-assigned MAC is used.
  3660. If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
  3661. will be programmed into hardware as part of the initialization process. This
  3662. may be skipped by setting the appropriate 'ethmacskip' environment variable.
  3663. The naming convention is as follows:
  3664. "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
  3665. Image Formats:
  3666. ==============
  3667. U-Boot is capable of booting (and performing other auxiliary operations on)
  3668. images in two formats:
  3669. New uImage format (FIT)
  3670. -----------------------
  3671. Flexible and powerful format based on Flattened Image Tree -- FIT (similar
  3672. to Flattened Device Tree). It allows the use of images with multiple
  3673. components (several kernels, ramdisks, etc.), with contents protected by
  3674. SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
  3675. Old uImage format
  3676. -----------------
  3677. Old image format is based on binary files which can be basically anything,
  3678. preceded by a special header; see the definitions in include/image.h for
  3679. details; basically, the header defines the following image properties:
  3680. * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
  3681. 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
  3682. LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
  3683. Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
  3684. INTEGRITY).
  3685. * Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
  3686. IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
  3687. Currently supported: ARM, Intel x86, MIPS, NDS32, Nios II, PowerPC).
  3688. * Compression Type (uncompressed, gzip, bzip2)
  3689. * Load Address
  3690. * Entry Point
  3691. * Image Name
  3692. * Image Timestamp
  3693. The header is marked by a special Magic Number, and both the header
  3694. and the data portions of the image are secured against corruption by
  3695. CRC32 checksums.
  3696. Linux Support:
  3697. ==============
  3698. Although U-Boot should support any OS or standalone application
  3699. easily, the main focus has always been on Linux during the design of
  3700. U-Boot.
  3701. U-Boot includes many features that so far have been part of some
  3702. special "boot loader" code within the Linux kernel. Also, any
  3703. "initrd" images to be used are no longer part of one big Linux image;
  3704. instead, kernel and "initrd" are separate images. This implementation
  3705. serves several purposes:
  3706. - the same features can be used for other OS or standalone
  3707. applications (for instance: using compressed images to reduce the
  3708. Flash memory footprint)
  3709. - it becomes much easier to port new Linux kernel versions because
  3710. lots of low-level, hardware dependent stuff are done by U-Boot
  3711. - the same Linux kernel image can now be used with different "initrd"
  3712. images; of course this also means that different kernel images can
  3713. be run with the same "initrd". This makes testing easier (you don't
  3714. have to build a new "zImage.initrd" Linux image when you just
  3715. change a file in your "initrd"). Also, a field-upgrade of the
  3716. software is easier now.
  3717. Linux HOWTO:
  3718. ============
  3719. Porting Linux to U-Boot based systems:
  3720. ---------------------------------------
  3721. U-Boot cannot save you from doing all the necessary modifications to
  3722. configure the Linux device drivers for use with your target hardware
  3723. (no, we don't intend to provide a full virtual machine interface to
  3724. Linux :-).
  3725. But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
  3726. Just make sure your machine specific header file (for instance
  3727. include/asm-ppc/tqm8xx.h) includes the same definition of the Board
  3728. Information structure as we define in include/asm-<arch>/u-boot.h,
  3729. and make sure that your definition of IMAP_ADDR uses the same value
  3730. as your U-Boot configuration in CONFIG_SYS_IMMR.
  3731. Note that U-Boot now has a driver model, a unified model for drivers.
  3732. If you are adding a new driver, plumb it into driver model. If there
  3733. is no uclass available, you are encouraged to create one. See
  3734. doc/driver-model.
  3735. Configuring the Linux kernel:
  3736. -----------------------------
  3737. No specific requirements for U-Boot. Make sure you have some root
  3738. device (initial ramdisk, NFS) for your target system.
  3739. Building a Linux Image:
  3740. -----------------------
  3741. With U-Boot, "normal" build targets like "zImage" or "bzImage" are
  3742. not used. If you use recent kernel source, a new build target
  3743. "uImage" will exist which automatically builds an image usable by
  3744. U-Boot. Most older kernels also have support for a "pImage" target,
  3745. which was introduced for our predecessor project PPCBoot and uses a
  3746. 100% compatible format.
  3747. Example:
  3748. make TQM850L_defconfig
  3749. make oldconfig
  3750. make dep
  3751. make uImage
  3752. The "uImage" build target uses a special tool (in 'tools/mkimage') to
  3753. encapsulate a compressed Linux kernel image with header information,
  3754. CRC32 checksum etc. for use with U-Boot. This is what we are doing:
  3755. * build a standard "vmlinux" kernel image (in ELF binary format):
  3756. * convert the kernel into a raw binary image:
  3757. ${CROSS_COMPILE}-objcopy -O binary \
  3758. -R .note -R .comment \
  3759. -S vmlinux linux.bin
  3760. * compress the binary image:
  3761. gzip -9 linux.bin
  3762. * package compressed binary image for U-Boot:
  3763. mkimage -A ppc -O linux -T kernel -C gzip \
  3764. -a 0 -e 0 -n "Linux Kernel Image" \
  3765. -d linux.bin.gz uImage
  3766. The "mkimage" tool can also be used to create ramdisk images for use
  3767. with U-Boot, either separated from the Linux kernel image, or
  3768. combined into one file. "mkimage" encapsulates the images with a 64
  3769. byte header containing information about target architecture,
  3770. operating system, image type, compression method, entry points, time
  3771. stamp, CRC32 checksums, etc.
  3772. "mkimage" can be called in two ways: to verify existing images and
  3773. print the header information, or to build new images.
  3774. In the first form (with "-l" option) mkimage lists the information
  3775. contained in the header of an existing U-Boot image; this includes
  3776. checksum verification:
  3777. tools/mkimage -l image
  3778. -l ==> list image header information
  3779. The second form (with "-d" option) is used to build a U-Boot image
  3780. from a "data file" which is used as image payload:
  3781. tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
  3782. -n name -d data_file image
  3783. -A ==> set architecture to 'arch'
  3784. -O ==> set operating system to 'os'
  3785. -T ==> set image type to 'type'
  3786. -C ==> set compression type 'comp'
  3787. -a ==> set load address to 'addr' (hex)
  3788. -e ==> set entry point to 'ep' (hex)
  3789. -n ==> set image name to 'name'
  3790. -d ==> use image data from 'datafile'
  3791. Right now, all Linux kernels for PowerPC systems use the same load
  3792. address (0x00000000), but the entry point address depends on the
  3793. kernel version:
  3794. - 2.2.x kernels have the entry point at 0x0000000C,
  3795. - 2.3.x and later kernels have the entry point at 0x00000000.
  3796. So a typical call to build a U-Boot image would read:
  3797. -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
  3798. > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
  3799. > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
  3800. > examples/uImage.TQM850L
  3801. Image Name: 2.4.4 kernel for TQM850L
  3802. Created: Wed Jul 19 02:34:59 2000
  3803. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  3804. Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
  3805. Load Address: 0x00000000
  3806. Entry Point: 0x00000000
  3807. To verify the contents of the image (or check for corruption):
  3808. -> tools/mkimage -l examples/uImage.TQM850L
  3809. Image Name: 2.4.4 kernel for TQM850L
  3810. Created: Wed Jul 19 02:34:59 2000
  3811. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  3812. Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
  3813. Load Address: 0x00000000
  3814. Entry Point: 0x00000000
  3815. NOTE: for embedded systems where boot time is critical you can trade
  3816. speed for memory and install an UNCOMPRESSED image instead: this
  3817. needs more space in Flash, but boots much faster since it does not
  3818. need to be uncompressed:
  3819. -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
  3820. -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
  3821. > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
  3822. > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
  3823. > examples/uImage.TQM850L-uncompressed
  3824. Image Name: 2.4.4 kernel for TQM850L
  3825. Created: Wed Jul 19 02:34:59 2000
  3826. Image Type: PowerPC Linux Kernel Image (uncompressed)
  3827. Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
  3828. Load Address: 0x00000000
  3829. Entry Point: 0x00000000
  3830. Similar you can build U-Boot images from a 'ramdisk.image.gz' file
  3831. when your kernel is intended to use an initial ramdisk:
  3832. -> tools/mkimage -n 'Simple Ramdisk Image' \
  3833. > -A ppc -O linux -T ramdisk -C gzip \
  3834. > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
  3835. Image Name: Simple Ramdisk Image
  3836. Created: Wed Jan 12 14:01:50 2000
  3837. Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
  3838. Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
  3839. Load Address: 0x00000000
  3840. Entry Point: 0x00000000
  3841. The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i"
  3842. option performs the converse operation of the mkimage's second form (the "-d"
  3843. option). Given an image built by mkimage, the dumpimage extracts a "data file"
  3844. from the image:
  3845. tools/dumpimage -i image -T type -p position data_file
  3846. -i ==> extract from the 'image' a specific 'data_file'
  3847. -T ==> set image type to 'type'
  3848. -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image'
  3849. Installing a Linux Image:
  3850. -------------------------
  3851. To downloading a U-Boot image over the serial (console) interface,
  3852. you must convert the image to S-Record format:
  3853. objcopy -I binary -O srec examples/image examples/image.srec
  3854. The 'objcopy' does not understand the information in the U-Boot
  3855. image header, so the resulting S-Record file will be relative to
  3856. address 0x00000000. To load it to a given address, you need to
  3857. specify the target address as 'offset' parameter with the 'loads'
  3858. command.
  3859. Example: install the image to address 0x40100000 (which on the
  3860. TQM8xxL is in the first Flash bank):
  3861. => erase 40100000 401FFFFF
  3862. .......... done
  3863. Erased 8 sectors
  3864. => loads 40100000
  3865. ## Ready for S-Record download ...
  3866. ~>examples/image.srec
  3867. 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
  3868. ...
  3869. 15989 15990 15991 15992
  3870. [file transfer complete]
  3871. [connected]
  3872. ## Start Addr = 0x00000000
  3873. You can check the success of the download using the 'iminfo' command;
  3874. this includes a checksum verification so you can be sure no data
  3875. corruption happened:
  3876. => imi 40100000
  3877. ## Checking Image at 40100000 ...
  3878. Image Name: 2.2.13 for initrd on TQM850L
  3879. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  3880. Data Size: 335725 Bytes = 327 kB = 0 MB
  3881. Load Address: 00000000
  3882. Entry Point: 0000000c
  3883. Verifying Checksum ... OK
  3884. Boot Linux:
  3885. -----------
  3886. The "bootm" command is used to boot an application that is stored in
  3887. memory (RAM or Flash). In case of a Linux kernel image, the contents
  3888. of the "bootargs" environment variable is passed to the kernel as
  3889. parameters. You can check and modify this variable using the
  3890. "printenv" and "setenv" commands:
  3891. => printenv bootargs
  3892. bootargs=root=/dev/ram
  3893. => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
  3894. => printenv bootargs
  3895. bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
  3896. => bootm 40020000
  3897. ## Booting Linux kernel at 40020000 ...
  3898. Image Name: 2.2.13 for NFS on TQM850L
  3899. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  3900. Data Size: 381681 Bytes = 372 kB = 0 MB
  3901. Load Address: 00000000
  3902. Entry Point: 0000000c
  3903. Verifying Checksum ... OK
  3904. Uncompressing Kernel Image ... OK
  3905. Linux version 2.2.13 (wd@denx.local.net) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:35:17 MEST 2000
  3906. Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
  3907. time_init: decrementer frequency = 187500000/60
  3908. Calibrating delay loop... 49.77 BogoMIPS
  3909. Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
  3910. ...
  3911. If you want to boot a Linux kernel with initial RAM disk, you pass
  3912. the memory addresses of both the kernel and the initrd image (PPBCOOT
  3913. format!) to the "bootm" command:
  3914. => imi 40100000 40200000
  3915. ## Checking Image at 40100000 ...
  3916. Image Name: 2.2.13 for initrd on TQM850L
  3917. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  3918. Data Size: 335725 Bytes = 327 kB = 0 MB
  3919. Load Address: 00000000
  3920. Entry Point: 0000000c
  3921. Verifying Checksum ... OK
  3922. ## Checking Image at 40200000 ...
  3923. Image Name: Simple Ramdisk Image
  3924. Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
  3925. Data Size: 566530 Bytes = 553 kB = 0 MB
  3926. Load Address: 00000000
  3927. Entry Point: 00000000
  3928. Verifying Checksum ... OK
  3929. => bootm 40100000 40200000
  3930. ## Booting Linux kernel at 40100000 ...
  3931. Image Name: 2.2.13 for initrd on TQM850L
  3932. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  3933. Data Size: 335725 Bytes = 327 kB = 0 MB
  3934. Load Address: 00000000
  3935. Entry Point: 0000000c
  3936. Verifying Checksum ... OK
  3937. Uncompressing Kernel Image ... OK
  3938. ## Loading RAMDisk Image at 40200000 ...
  3939. Image Name: Simple Ramdisk Image
  3940. Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
  3941. Data Size: 566530 Bytes = 553 kB = 0 MB
  3942. Load Address: 00000000
  3943. Entry Point: 00000000
  3944. Verifying Checksum ... OK
  3945. Loading Ramdisk ... OK
  3946. Linux version 2.2.13 (wd@denx.local.net) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:32:08 MEST 2000
  3947. Boot arguments: root=/dev/ram
  3948. time_init: decrementer frequency = 187500000/60
  3949. Calibrating delay loop... 49.77 BogoMIPS
  3950. ...
  3951. RAMDISK: Compressed image found at block 0
  3952. VFS: Mounted root (ext2 filesystem).
  3953. bash#
  3954. Boot Linux and pass a flat device tree:
  3955. -----------
  3956. First, U-Boot must be compiled with the appropriate defines. See the section
  3957. titled "Linux Kernel Interface" above for a more in depth explanation. The
  3958. following is an example of how to start a kernel and pass an updated
  3959. flat device tree:
  3960. => print oftaddr
  3961. oftaddr=0x300000
  3962. => print oft
  3963. oft=oftrees/mpc8540ads.dtb
  3964. => tftp $oftaddr $oft
  3965. Speed: 1000, full duplex
  3966. Using TSEC0 device
  3967. TFTP from server 192.168.1.1; our IP address is 192.168.1.101
  3968. Filename 'oftrees/mpc8540ads.dtb'.
  3969. Load address: 0x300000
  3970. Loading: #
  3971. done
  3972. Bytes transferred = 4106 (100a hex)
  3973. => tftp $loadaddr $bootfile
  3974. Speed: 1000, full duplex
  3975. Using TSEC0 device
  3976. TFTP from server 192.168.1.1; our IP address is 192.168.1.2
  3977. Filename 'uImage'.
  3978. Load address: 0x200000
  3979. Loading:############
  3980. done
  3981. Bytes transferred = 1029407 (fb51f hex)
  3982. => print loadaddr
  3983. loadaddr=200000
  3984. => print oftaddr
  3985. oftaddr=0x300000
  3986. => bootm $loadaddr - $oftaddr
  3987. ## Booting image at 00200000 ...
  3988. Image Name: Linux-2.6.17-dirty
  3989. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  3990. Data Size: 1029343 Bytes = 1005.2 kB
  3991. Load Address: 00000000
  3992. Entry Point: 00000000
  3993. Verifying Checksum ... OK
  3994. Uncompressing Kernel Image ... OK
  3995. Booting using flat device tree at 0x300000
  3996. Using MPC85xx ADS machine description
  3997. Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
  3998. [snip]
  3999. More About U-Boot Image Types:
  4000. ------------------------------
  4001. U-Boot supports the following image types:
  4002. "Standalone Programs" are directly runnable in the environment
  4003. provided by U-Boot; it is expected that (if they behave
  4004. well) you can continue to work in U-Boot after return from
  4005. the Standalone Program.
  4006. "OS Kernel Images" are usually images of some Embedded OS which
  4007. will take over control completely. Usually these programs
  4008. will install their own set of exception handlers, device
  4009. drivers, set up the MMU, etc. - this means, that you cannot
  4010. expect to re-enter U-Boot except by resetting the CPU.
  4011. "RAMDisk Images" are more or less just data blocks, and their
  4012. parameters (address, size) are passed to an OS kernel that is
  4013. being started.
  4014. "Multi-File Images" contain several images, typically an OS
  4015. (Linux) kernel image and one or more data images like
  4016. RAMDisks. This construct is useful for instance when you want
  4017. to boot over the network using BOOTP etc., where the boot
  4018. server provides just a single image file, but you want to get
  4019. for instance an OS kernel and a RAMDisk image.
  4020. "Multi-File Images" start with a list of image sizes, each
  4021. image size (in bytes) specified by an "uint32_t" in network
  4022. byte order. This list is terminated by an "(uint32_t)0".
  4023. Immediately after the terminating 0 follow the images, one by
  4024. one, all aligned on "uint32_t" boundaries (size rounded up to
  4025. a multiple of 4 bytes).
  4026. "Firmware Images" are binary images containing firmware (like
  4027. U-Boot or FPGA images) which usually will be programmed to
  4028. flash memory.
  4029. "Script files" are command sequences that will be executed by
  4030. U-Boot's command interpreter; this feature is especially
  4031. useful when you configure U-Boot to use a real shell (hush)
  4032. as command interpreter.
  4033. Booting the Linux zImage:
  4034. -------------------------
  4035. On some platforms, it's possible to boot Linux zImage. This is done
  4036. using the "bootz" command. The syntax of "bootz" command is the same
  4037. as the syntax of "bootm" command.
  4038. Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
  4039. kernel with raw initrd images. The syntax is slightly different, the
  4040. address of the initrd must be augmented by it's size, in the following
  4041. format: "<initrd addres>:<initrd size>".
  4042. Standalone HOWTO:
  4043. =================
  4044. One of the features of U-Boot is that you can dynamically load and
  4045. run "standalone" applications, which can use some resources of
  4046. U-Boot like console I/O functions or interrupt services.
  4047. Two simple examples are included with the sources:
  4048. "Hello World" Demo:
  4049. -------------------
  4050. 'examples/hello_world.c' contains a small "Hello World" Demo
  4051. application; it is automatically compiled when you build U-Boot.
  4052. It's configured to run at address 0x00040004, so you can play with it
  4053. like that:
  4054. => loads
  4055. ## Ready for S-Record download ...
  4056. ~>examples/hello_world.srec
  4057. 1 2 3 4 5 6 7 8 9 10 11 ...
  4058. [file transfer complete]
  4059. [connected]
  4060. ## Start Addr = 0x00040004
  4061. => go 40004 Hello World! This is a test.
  4062. ## Starting application at 0x00040004 ...
  4063. Hello World
  4064. argc = 7
  4065. argv[0] = "40004"
  4066. argv[1] = "Hello"
  4067. argv[2] = "World!"
  4068. argv[3] = "This"
  4069. argv[4] = "is"
  4070. argv[5] = "a"
  4071. argv[6] = "test."
  4072. argv[7] = "<NULL>"
  4073. Hit any key to exit ...
  4074. ## Application terminated, rc = 0x0
  4075. Another example, which demonstrates how to register a CPM interrupt
  4076. handler with the U-Boot code, can be found in 'examples/timer.c'.
  4077. Here, a CPM timer is set up to generate an interrupt every second.
  4078. The interrupt service routine is trivial, just printing a '.'
  4079. character, but this is just a demo program. The application can be
  4080. controlled by the following keys:
  4081. ? - print current values og the CPM Timer registers
  4082. b - enable interrupts and start timer
  4083. e - stop timer and disable interrupts
  4084. q - quit application
  4085. => loads
  4086. ## Ready for S-Record download ...
  4087. ~>examples/timer.srec
  4088. 1 2 3 4 5 6 7 8 9 10 11 ...
  4089. [file transfer complete]
  4090. [connected]
  4091. ## Start Addr = 0x00040004
  4092. => go 40004
  4093. ## Starting application at 0x00040004 ...
  4094. TIMERS=0xfff00980
  4095. Using timer 1
  4096. tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
  4097. Hit 'b':
  4098. [q, b, e, ?] Set interval 1000000 us
  4099. Enabling timer
  4100. Hit '?':
  4101. [q, b, e, ?] ........
  4102. tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
  4103. Hit '?':
  4104. [q, b, e, ?] .
  4105. tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
  4106. Hit '?':
  4107. [q, b, e, ?] .
  4108. tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
  4109. Hit '?':
  4110. [q, b, e, ?] .
  4111. tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
  4112. Hit 'e':
  4113. [q, b, e, ?] ...Stopping timer
  4114. Hit 'q':
  4115. [q, b, e, ?] ## Application terminated, rc = 0x0
  4116. Minicom warning:
  4117. ================
  4118. Over time, many people have reported problems when trying to use the
  4119. "minicom" terminal emulation program for serial download. I (wd)
  4120. consider minicom to be broken, and recommend not to use it. Under
  4121. Unix, I recommend to use C-Kermit for general purpose use (and
  4122. especially for kermit binary protocol download ("loadb" command), and
  4123. use "cu" for S-Record download ("loads" command). See
  4124. http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
  4125. for help with kermit.
  4126. Nevertheless, if you absolutely want to use it try adding this
  4127. configuration to your "File transfer protocols" section:
  4128. Name Program Name U/D FullScr IO-Red. Multi
  4129. X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
  4130. Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
  4131. NetBSD Notes:
  4132. =============
  4133. Starting at version 0.9.2, U-Boot supports NetBSD both as host
  4134. (build U-Boot) and target system (boots NetBSD/mpc8xx).
  4135. Building requires a cross environment; it is known to work on
  4136. NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
  4137. need gmake since the Makefiles are not compatible with BSD make).
  4138. Note that the cross-powerpc package does not install include files;
  4139. attempting to build U-Boot will fail because <machine/ansi.h> is
  4140. missing. This file has to be installed and patched manually:
  4141. # cd /usr/pkg/cross/powerpc-netbsd/include
  4142. # mkdir powerpc
  4143. # ln -s powerpc machine
  4144. # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
  4145. # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
  4146. Native builds *don't* work due to incompatibilities between native
  4147. and U-Boot include files.
  4148. Booting assumes that (the first part of) the image booted is a
  4149. stage-2 loader which in turn loads and then invokes the kernel
  4150. proper. Loader sources will eventually appear in the NetBSD source
  4151. tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
  4152. meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
  4153. Implementation Internals:
  4154. =========================
  4155. The following is not intended to be a complete description of every
  4156. implementation detail. However, it should help to understand the
  4157. inner workings of U-Boot and make it easier to port it to custom
  4158. hardware.
  4159. Initial Stack, Global Data:
  4160. ---------------------------
  4161. The implementation of U-Boot is complicated by the fact that U-Boot
  4162. starts running out of ROM (flash memory), usually without access to
  4163. system RAM (because the memory controller is not initialized yet).
  4164. This means that we don't have writable Data or BSS segments, and BSS
  4165. is not initialized as zero. To be able to get a C environment working
  4166. at all, we have to allocate at least a minimal stack. Implementation
  4167. options for this are defined and restricted by the CPU used: Some CPU
  4168. models provide on-chip memory (like the IMMR area on MPC8xx and
  4169. MPC826x processors), on others (parts of) the data cache can be
  4170. locked as (mis-) used as memory, etc.
  4171. Chris Hallinan posted a good summary of these issues to the
  4172. U-Boot mailing list:
  4173. Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
  4174. From: "Chris Hallinan" <clh@net1plus.com>
  4175. Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
  4176. ...
  4177. Correct me if I'm wrong, folks, but the way I understand it
  4178. is this: Using DCACHE as initial RAM for Stack, etc, does not
  4179. require any physical RAM backing up the cache. The cleverness
  4180. is that the cache is being used as a temporary supply of
  4181. necessary storage before the SDRAM controller is setup. It's
  4182. beyond the scope of this list to explain the details, but you
  4183. can see how this works by studying the cache architecture and
  4184. operation in the architecture and processor-specific manuals.
  4185. OCM is On Chip Memory, which I believe the 405GP has 4K. It
  4186. is another option for the system designer to use as an
  4187. initial stack/RAM area prior to SDRAM being available. Either
  4188. option should work for you. Using CS 4 should be fine if your
  4189. board designers haven't used it for something that would
  4190. cause you grief during the initial boot! It is frequently not
  4191. used.
  4192. CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
  4193. with your processor/board/system design. The default value
  4194. you will find in any recent u-boot distribution in
  4195. walnut.h should work for you. I'd set it to a value larger
  4196. than your SDRAM module. If you have a 64MB SDRAM module, set
  4197. it above 400_0000. Just make sure your board has no resources
  4198. that are supposed to respond to that address! That code in
  4199. start.S has been around a while and should work as is when
  4200. you get the config right.
  4201. -Chris Hallinan
  4202. DS4.COM, Inc.
  4203. It is essential to remember this, since it has some impact on the C
  4204. code for the initialization procedures:
  4205. * Initialized global data (data segment) is read-only. Do not attempt
  4206. to write it.
  4207. * Do not use any uninitialized global data (or implicitly initialized
  4208. as zero data - BSS segment) at all - this is undefined, initiali-
  4209. zation is performed later (when relocating to RAM).
  4210. * Stack space is very limited. Avoid big data buffers or things like
  4211. that.
  4212. Having only the stack as writable memory limits means we cannot use
  4213. normal global data to share information between the code. But it
  4214. turned out that the implementation of U-Boot can be greatly
  4215. simplified by making a global data structure (gd_t) available to all
  4216. functions. We could pass a pointer to this data as argument to _all_
  4217. functions, but this would bloat the code. Instead we use a feature of
  4218. the GCC compiler (Global Register Variables) to share the data: we
  4219. place a pointer (gd) to the global data into a register which we
  4220. reserve for this purpose.
  4221. When choosing a register for such a purpose we are restricted by the
  4222. relevant (E)ABI specifications for the current architecture, and by
  4223. GCC's implementation.
  4224. For PowerPC, the following registers have specific use:
  4225. R1: stack pointer
  4226. R2: reserved for system use
  4227. R3-R4: parameter passing and return values
  4228. R5-R10: parameter passing
  4229. R13: small data area pointer
  4230. R30: GOT pointer
  4231. R31: frame pointer
  4232. (U-Boot also uses R12 as internal GOT pointer. r12
  4233. is a volatile register so r12 needs to be reset when
  4234. going back and forth between asm and C)
  4235. ==> U-Boot will use R2 to hold a pointer to the global data
  4236. Note: on PPC, we could use a static initializer (since the
  4237. address of the global data structure is known at compile time),
  4238. but it turned out that reserving a register results in somewhat
  4239. smaller code - although the code savings are not that big (on
  4240. average for all boards 752 bytes for the whole U-Boot image,
  4241. 624 text + 127 data).
  4242. On ARM, the following registers are used:
  4243. R0: function argument word/integer result
  4244. R1-R3: function argument word
  4245. R9: platform specific
  4246. R10: stack limit (used only if stack checking is enabled)
  4247. R11: argument (frame) pointer
  4248. R12: temporary workspace
  4249. R13: stack pointer
  4250. R14: link register
  4251. R15: program counter
  4252. ==> U-Boot will use R9 to hold a pointer to the global data
  4253. Note: on ARM, only R_ARM_RELATIVE relocations are supported.
  4254. On Nios II, the ABI is documented here:
  4255. http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
  4256. ==> U-Boot will use gp to hold a pointer to the global data
  4257. Note: on Nios II, we give "-G0" option to gcc and don't use gp
  4258. to access small data sections, so gp is free.
  4259. On NDS32, the following registers are used:
  4260. R0-R1: argument/return
  4261. R2-R5: argument
  4262. R15: temporary register for assembler
  4263. R16: trampoline register
  4264. R28: frame pointer (FP)
  4265. R29: global pointer (GP)
  4266. R30: link register (LP)
  4267. R31: stack pointer (SP)
  4268. PC: program counter (PC)
  4269. ==> U-Boot will use R10 to hold a pointer to the global data
  4270. NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
  4271. or current versions of GCC may "optimize" the code too much.
  4272. Memory Management:
  4273. ------------------
  4274. U-Boot runs in system state and uses physical addresses, i.e. the
  4275. MMU is not used either for address mapping nor for memory protection.
  4276. The available memory is mapped to fixed addresses using the memory
  4277. controller. In this process, a contiguous block is formed for each
  4278. memory type (Flash, SDRAM, SRAM), even when it consists of several
  4279. physical memory banks.
  4280. U-Boot is installed in the first 128 kB of the first Flash bank (on
  4281. TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
  4282. booting and sizing and initializing DRAM, the code relocates itself
  4283. to the upper end of DRAM. Immediately below the U-Boot code some
  4284. memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
  4285. configuration setting]. Below that, a structure with global Board
  4286. Info data is placed, followed by the stack (growing downward).
  4287. Additionally, some exception handler code is copied to the low 8 kB
  4288. of DRAM (0x00000000 ... 0x00001FFF).
  4289. So a typical memory configuration with 16 MB of DRAM could look like
  4290. this:
  4291. 0x0000 0000 Exception Vector code
  4292. :
  4293. 0x0000 1FFF
  4294. 0x0000 2000 Free for Application Use
  4295. :
  4296. :
  4297. :
  4298. :
  4299. 0x00FB FF20 Monitor Stack (Growing downward)
  4300. 0x00FB FFAC Board Info Data and permanent copy of global data
  4301. 0x00FC 0000 Malloc Arena
  4302. :
  4303. 0x00FD FFFF
  4304. 0x00FE 0000 RAM Copy of Monitor Code
  4305. ... eventually: LCD or video framebuffer
  4306. ... eventually: pRAM (Protected RAM - unchanged by reset)
  4307. 0x00FF FFFF [End of RAM]
  4308. System Initialization:
  4309. ----------------------
  4310. In the reset configuration, U-Boot starts at the reset entry point
  4311. (on most PowerPC systems at address 0x00000100). Because of the reset
  4312. configuration for CS0# this is a mirror of the on board Flash memory.
  4313. To be able to re-map memory U-Boot then jumps to its link address.
  4314. To be able to implement the initialization code in C, a (small!)
  4315. initial stack is set up in the internal Dual Ported RAM (in case CPUs
  4316. which provide such a feature like), or in a locked part of the data
  4317. cache. After that, U-Boot initializes the CPU core, the caches and
  4318. the SIU.
  4319. Next, all (potentially) available memory banks are mapped using a
  4320. preliminary mapping. For example, we put them on 512 MB boundaries
  4321. (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
  4322. on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
  4323. programmed for SDRAM access. Using the temporary configuration, a
  4324. simple memory test is run that determines the size of the SDRAM
  4325. banks.
  4326. When there is more than one SDRAM bank, and the banks are of
  4327. different size, the largest is mapped first. For equal size, the first
  4328. bank (CS2#) is mapped first. The first mapping is always for address
  4329. 0x00000000, with any additional banks following immediately to create
  4330. contiguous memory starting from 0.
  4331. Then, the monitor installs itself at the upper end of the SDRAM area
  4332. and allocates memory for use by malloc() and for the global Board
  4333. Info data; also, the exception vector code is copied to the low RAM
  4334. pages, and the final stack is set up.
  4335. Only after this relocation will you have a "normal" C environment;
  4336. until that you are restricted in several ways, mostly because you are
  4337. running from ROM, and because the code will have to be relocated to a
  4338. new address in RAM.
  4339. U-Boot Porting Guide:
  4340. ----------------------
  4341. [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
  4342. list, October 2002]
  4343. int main(int argc, char *argv[])
  4344. {
  4345. sighandler_t no_more_time;
  4346. signal(SIGALRM, no_more_time);
  4347. alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
  4348. if (available_money > available_manpower) {
  4349. Pay consultant to port U-Boot;
  4350. return 0;
  4351. }
  4352. Download latest U-Boot source;
  4353. Subscribe to u-boot mailing list;
  4354. if (clueless)
  4355. email("Hi, I am new to U-Boot, how do I get started?");
  4356. while (learning) {
  4357. Read the README file in the top level directory;
  4358. Read http://www.denx.de/twiki/bin/view/DULG/Manual;
  4359. Read applicable doc/*.README;
  4360. Read the source, Luke;
  4361. /* find . -name "*.[chS]" | xargs grep -i <keyword> */
  4362. }
  4363. if (available_money > toLocalCurrency ($2500))
  4364. Buy a BDI3000;
  4365. else
  4366. Add a lot of aggravation and time;
  4367. if (a similar board exists) { /* hopefully... */
  4368. cp -a board/<similar> board/<myboard>
  4369. cp include/configs/<similar>.h include/configs/<myboard>.h
  4370. } else {
  4371. Create your own board support subdirectory;
  4372. Create your own board include/configs/<myboard>.h file;
  4373. }
  4374. Edit new board/<myboard> files
  4375. Edit new include/configs/<myboard>.h
  4376. while (!accepted) {
  4377. while (!running) {
  4378. do {
  4379. Add / modify source code;
  4380. } until (compiles);
  4381. Debug;
  4382. if (clueless)
  4383. email("Hi, I am having problems...");
  4384. }
  4385. Send patch file to the U-Boot email list;
  4386. if (reasonable critiques)
  4387. Incorporate improvements from email list code review;
  4388. else
  4389. Defend code as written;
  4390. }
  4391. return 0;
  4392. }
  4393. void no_more_time (int sig)
  4394. {
  4395. hire_a_guru();
  4396. }
  4397. Coding Standards:
  4398. -----------------
  4399. All contributions to U-Boot should conform to the Linux kernel
  4400. coding style; see the file "Documentation/CodingStyle" and the script
  4401. "scripts/Lindent" in your Linux kernel source directory.
  4402. Source files originating from a different project (for example the
  4403. MTD subsystem) are generally exempt from these guidelines and are not
  4404. reformatted to ease subsequent migration to newer versions of those
  4405. sources.
  4406. Please note that U-Boot is implemented in C (and to some small parts in
  4407. Assembler); no C++ is used, so please do not use C++ style comments (//)
  4408. in your code.
  4409. Please also stick to the following formatting rules:
  4410. - remove any trailing white space
  4411. - use TAB characters for indentation and vertical alignment, not spaces
  4412. - make sure NOT to use DOS '\r\n' line feeds
  4413. - do not add more than 2 consecutive empty lines to source files
  4414. - do not add trailing empty lines to source files
  4415. Submissions which do not conform to the standards may be returned
  4416. with a request to reformat the changes.
  4417. Submitting Patches:
  4418. -------------------
  4419. Since the number of patches for U-Boot is growing, we need to
  4420. establish some rules. Submissions which do not conform to these rules
  4421. may be rejected, even when they contain important and valuable stuff.
  4422. Please see http://www.denx.de/wiki/U-Boot/Patches for details.
  4423. Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
  4424. see http://lists.denx.de/mailman/listinfo/u-boot
  4425. When you send a patch, please include the following information with
  4426. it:
  4427. * For bug fixes: a description of the bug and how your patch fixes
  4428. this bug. Please try to include a way of demonstrating that the
  4429. patch actually fixes something.
  4430. * For new features: a description of the feature and your
  4431. implementation.
  4432. * A CHANGELOG entry as plaintext (separate from the patch)
  4433. * For major contributions, add a MAINTAINERS file with your
  4434. information and associated file and directory references.
  4435. * When you add support for a new board, don't forget to add a
  4436. maintainer e-mail address to the boards.cfg file, too.
  4437. * If your patch adds new configuration options, don't forget to
  4438. document these in the README file.
  4439. * The patch itself. If you are using git (which is *strongly*
  4440. recommended) you can easily generate the patch using the
  4441. "git format-patch". If you then use "git send-email" to send it to
  4442. the U-Boot mailing list, you will avoid most of the common problems
  4443. with some other mail clients.
  4444. If you cannot use git, use "diff -purN OLD NEW". If your version of
  4445. diff does not support these options, then get the latest version of
  4446. GNU diff.
  4447. The current directory when running this command shall be the parent
  4448. directory of the U-Boot source tree (i. e. please make sure that
  4449. your patch includes sufficient directory information for the
  4450. affected files).
  4451. We prefer patches as plain text. MIME attachments are discouraged,
  4452. and compressed attachments must not be used.
  4453. * If one logical set of modifications affects or creates several
  4454. files, all these changes shall be submitted in a SINGLE patch file.
  4455. * Changesets that contain different, unrelated modifications shall be
  4456. submitted as SEPARATE patches, one patch per changeset.
  4457. Notes:
  4458. * Before sending the patch, run the buildman script on your patched
  4459. source tree and make sure that no errors or warnings are reported
  4460. for any of the boards.
  4461. * Keep your modifications to the necessary minimum: A patch
  4462. containing several unrelated changes or arbitrary reformats will be
  4463. returned with a request to re-formatting / split it.
  4464. * If you modify existing code, make sure that your new code does not
  4465. add to the memory footprint of the code ;-) Small is beautiful!
  4466. When adding new features, these should compile conditionally only
  4467. (using #ifdef), and the resulting code with the new feature
  4468. disabled must not need more memory than the old code without your
  4469. modification.
  4470. * Remember that there is a size limit of 100 kB per message on the
  4471. u-boot mailing list. Bigger patches will be moderated. If they are
  4472. reasonable and not too big, they will be acknowledged. But patches
  4473. bigger than the size limit should be avoided.