fdtdec.h 24 KB

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  1. /*
  2. * Copyright (c) 2011 The Chromium OS Authors.
  3. * SPDX-License-Identifier: GPL-2.0+
  4. */
  5. #ifndef __fdtdec_h
  6. #define __fdtdec_h
  7. /*
  8. * This file contains convenience functions for decoding useful and
  9. * enlightening information from FDTs. It is intended to be used by device
  10. * drivers and board-specific code within U-Boot. It aims to reduce the
  11. * amount of FDT munging required within U-Boot itself, so that driver code
  12. * changes to support FDT are minimized.
  13. */
  14. #include <libfdt.h>
  15. /*
  16. * A typedef for a physical address. Note that fdt data is always big
  17. * endian even on a litle endian machine.
  18. */
  19. #ifdef CONFIG_PHYS_64BIT
  20. typedef u64 fdt_addr_t;
  21. typedef u64 fdt_size_t;
  22. #define FDT_ADDR_T_NONE (-1ULL)
  23. #define fdt_addr_to_cpu(reg) be64_to_cpu(reg)
  24. #define fdt_size_to_cpu(reg) be64_to_cpu(reg)
  25. #else
  26. typedef u32 fdt_addr_t;
  27. typedef u32 fdt_size_t;
  28. #define FDT_ADDR_T_NONE (-1U)
  29. #define fdt_addr_to_cpu(reg) be32_to_cpu(reg)
  30. #define fdt_size_to_cpu(reg) be32_to_cpu(reg)
  31. #endif
  32. /* Information obtained about memory from the FDT */
  33. struct fdt_memory {
  34. fdt_addr_t start;
  35. fdt_addr_t end;
  36. };
  37. /*
  38. * Information about a resource. start is the first address of the resource
  39. * and end is the last address (inclusive). The length of the resource will
  40. * be equal to: end - start + 1.
  41. */
  42. struct fdt_resource {
  43. fdt_addr_t start;
  44. fdt_addr_t end;
  45. };
  46. /**
  47. * Compute the size of a resource.
  48. *
  49. * @param res the resource to operate on
  50. * @return the size of the resource
  51. */
  52. static inline fdt_size_t fdt_resource_size(const struct fdt_resource *res)
  53. {
  54. return res->end - res->start + 1;
  55. }
  56. /**
  57. * Compat types that we know about and for which we might have drivers.
  58. * Each is named COMPAT_<dir>_<filename> where <dir> is the directory
  59. * within drivers.
  60. */
  61. enum fdt_compat_id {
  62. COMPAT_UNKNOWN,
  63. COMPAT_NVIDIA_TEGRA20_USB, /* Tegra20 USB port */
  64. COMPAT_NVIDIA_TEGRA30_USB, /* Tegra30 USB port */
  65. COMPAT_NVIDIA_TEGRA114_USB, /* Tegra114 USB port */
  66. COMPAT_NVIDIA_TEGRA114_I2C, /* Tegra114 I2C w/single clock source */
  67. COMPAT_NVIDIA_TEGRA20_I2C, /* Tegra20 i2c */
  68. COMPAT_NVIDIA_TEGRA20_DVC, /* Tegra20 dvc (really just i2c) */
  69. COMPAT_NVIDIA_TEGRA20_EMC, /* Tegra20 memory controller */
  70. COMPAT_NVIDIA_TEGRA20_EMC_TABLE, /* Tegra20 memory timing table */
  71. COMPAT_NVIDIA_TEGRA20_KBC, /* Tegra20 Keyboard */
  72. COMPAT_NVIDIA_TEGRA20_NAND, /* Tegra2 NAND controller */
  73. COMPAT_NVIDIA_TEGRA20_PWM, /* Tegra 2 PWM controller */
  74. COMPAT_NVIDIA_TEGRA20_DC, /* Tegra 2 Display controller */
  75. COMPAT_NVIDIA_TEGRA124_SDMMC, /* Tegra124 SDMMC controller */
  76. COMPAT_NVIDIA_TEGRA30_SDMMC, /* Tegra30 SDMMC controller */
  77. COMPAT_NVIDIA_TEGRA20_SDMMC, /* Tegra20 SDMMC controller */
  78. COMPAT_NVIDIA_TEGRA20_SFLASH, /* Tegra 2 SPI flash controller */
  79. COMPAT_NVIDIA_TEGRA20_SLINK, /* Tegra 2 SPI SLINK controller */
  80. COMPAT_NVIDIA_TEGRA114_SPI, /* Tegra 114 SPI controller */
  81. COMPAT_SMSC_LAN9215, /* SMSC 10/100 Ethernet LAN9215 */
  82. COMPAT_SAMSUNG_EXYNOS5_SROMC, /* Exynos5 SROMC */
  83. COMPAT_SAMSUNG_S3C2440_I2C, /* Exynos I2C Controller */
  84. COMPAT_SAMSUNG_EXYNOS5_SOUND, /* Exynos Sound */
  85. COMPAT_WOLFSON_WM8994_CODEC, /* Wolfson WM8994 Sound Codec */
  86. COMPAT_SAMSUNG_EXYNOS_SPI, /* Exynos SPI */
  87. COMPAT_GOOGLE_CROS_EC, /* Google CROS_EC Protocol */
  88. COMPAT_GOOGLE_CROS_EC_KEYB, /* Google CROS_EC Keyboard */
  89. COMPAT_SAMSUNG_EXYNOS_EHCI, /* Exynos EHCI controller */
  90. COMPAT_SAMSUNG_EXYNOS5_XHCI, /* Exynos5 XHCI controller */
  91. COMPAT_SAMSUNG_EXYNOS_USB_PHY, /* Exynos phy controller for usb2.0 */
  92. COMPAT_SAMSUNG_EXYNOS5_USB3_PHY,/* Exynos phy controller for usb3.0 */
  93. COMPAT_SAMSUNG_EXYNOS_TMU, /* Exynos TMU */
  94. COMPAT_SAMSUNG_EXYNOS_FIMD, /* Exynos Display controller */
  95. COMPAT_SAMSUNG_EXYNOS_MIPI_DSI, /* Exynos mipi dsi */
  96. COMPAT_SAMSUNG_EXYNOS5_DP, /* Exynos Display port controller */
  97. COMPAT_SAMSUNG_EXYNOS_DWMMC, /* Exynos DWMMC controller */
  98. COMPAT_SAMSUNG_EXYNOS_MMC, /* Exynos MMC controller */
  99. COMPAT_SAMSUNG_EXYNOS_SERIAL, /* Exynos UART */
  100. COMPAT_MAXIM_MAX77686_PMIC, /* MAX77686 PMIC */
  101. COMPAT_GENERIC_SPI_FLASH, /* Generic SPI Flash chip */
  102. COMPAT_MAXIM_98095_CODEC, /* MAX98095 Codec */
  103. COMPAT_INFINEON_SLB9635_TPM, /* Infineon SLB9635 TPM */
  104. COMPAT_INFINEON_SLB9645_TPM, /* Infineon SLB9645 TPM */
  105. COMPAT_SAMSUNG_EXYNOS5_I2C, /* Exynos5 High Speed I2C Controller */
  106. COMPAT_SANDBOX_HOST_EMULATION, /* Sandbox emulation of a function */
  107. COMPAT_SANDBOX_LCD_SDL, /* Sandbox LCD emulation with SDL */
  108. COMPAT_TI_TPS65090, /* Texas Instrument TPS65090 */
  109. COMPAT_NXP_PTN3460, /* NXP PTN3460 DP/LVDS bridge */
  110. COMPAT_SAMSUNG_EXYNOS_SYSMMU, /* Exynos sysmmu */
  111. COMPAT_PARADE_PS8625, /* Parade PS8622 EDP->LVDS bridge */
  112. COMPAT_INTEL_LPC, /* Intel Low Pin Count I/F */
  113. COMPAT_INTEL_MICROCODE, /* Intel microcode update */
  114. COMPAT_MEMORY_SPD, /* Memory SPD information */
  115. COMPAT_INTEL_PANTHERPOINT_AHCI, /* Intel Pantherpoint AHCI */
  116. COMPAT_COUNT,
  117. };
  118. /* GPIOs are numbered from 0 */
  119. enum {
  120. FDT_GPIO_NONE = -1U, /* an invalid GPIO used to end our list */
  121. FDT_GPIO_ACTIVE_LOW = 1 << 0, /* input is active low (else high) */
  122. };
  123. /* This is the state of a GPIO pin as defined by the fdt */
  124. struct fdt_gpio_state {
  125. const char *name; /* name of the fdt property defining this */
  126. uint gpio; /* GPIO number, or FDT_GPIO_NONE if none */
  127. u8 flags; /* FDT_GPIO_... flags */
  128. };
  129. /* This tells us whether a fdt_gpio_state record is valid or not */
  130. #define fdt_gpio_isvalid(x) ((x)->gpio != FDT_GPIO_NONE)
  131. /**
  132. * Read the GPIO taking into account the polarity of the pin.
  133. *
  134. * @param gpio pointer to the decoded gpio
  135. * @return value of the gpio if successful, < 0 if unsuccessful
  136. */
  137. int fdtdec_get_gpio(struct fdt_gpio_state *gpio);
  138. /**
  139. * Write the GPIO taking into account the polarity of the pin.
  140. *
  141. * @param gpio pointer to the decoded gpio
  142. * @return 0 if successful
  143. */
  144. int fdtdec_set_gpio(struct fdt_gpio_state *gpio, int val);
  145. /**
  146. * Find the next numbered alias for a peripheral. This is used to enumerate
  147. * all the peripherals of a certain type.
  148. *
  149. * Do the first call with *upto = 0. Assuming /aliases/<name>0 exists then
  150. * this function will return a pointer to the node the alias points to, and
  151. * then update *upto to 1. Next time you call this function, the next node
  152. * will be returned.
  153. *
  154. * All nodes returned will match the compatible ID, as it is assumed that
  155. * all peripherals use the same driver.
  156. *
  157. * @param blob FDT blob to use
  158. * @param name Root name of alias to search for
  159. * @param id Compatible ID to look for
  160. * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
  161. */
  162. int fdtdec_next_alias(const void *blob, const char *name,
  163. enum fdt_compat_id id, int *upto);
  164. /**
  165. * Find the compatible ID for a given node.
  166. *
  167. * Generally each node has at least one compatible string attached to it.
  168. * This function looks through our list of known compatible strings and
  169. * returns the corresponding ID which matches the compatible string.
  170. *
  171. * @param blob FDT blob to use
  172. * @param node Node containing compatible string to find
  173. * @return compatible ID, or COMPAT_UNKNOWN if we cannot find a match
  174. */
  175. enum fdt_compat_id fdtdec_lookup(const void *blob, int node);
  176. /**
  177. * Find the next compatible node for a peripheral.
  178. *
  179. * Do the first call with node = 0. This function will return a pointer to
  180. * the next compatible node. Next time you call this function, pass the
  181. * value returned, and the next node will be provided.
  182. *
  183. * @param blob FDT blob to use
  184. * @param node Start node for search
  185. * @param id Compatible ID to look for (enum fdt_compat_id)
  186. * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
  187. */
  188. int fdtdec_next_compatible(const void *blob, int node,
  189. enum fdt_compat_id id);
  190. /**
  191. * Find the next compatible subnode for a peripheral.
  192. *
  193. * Do the first call with node set to the parent and depth = 0. This
  194. * function will return the offset of the next compatible node. Next time
  195. * you call this function, pass the node value returned last time, with
  196. * depth unchanged, and the next node will be provided.
  197. *
  198. * @param blob FDT blob to use
  199. * @param node Start node for search
  200. * @param id Compatible ID to look for (enum fdt_compat_id)
  201. * @param depthp Current depth (set to 0 before first call)
  202. * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
  203. */
  204. int fdtdec_next_compatible_subnode(const void *blob, int node,
  205. enum fdt_compat_id id, int *depthp);
  206. /**
  207. * Look up an address property in a node and return it as an address.
  208. * The property must hold either one address with no trailing data or
  209. * one address with a length. This is only tested on 32-bit machines.
  210. *
  211. * @param blob FDT blob
  212. * @param node node to examine
  213. * @param prop_name name of property to find
  214. * @return address, if found, or FDT_ADDR_T_NONE if not
  215. */
  216. fdt_addr_t fdtdec_get_addr(const void *blob, int node,
  217. const char *prop_name);
  218. /**
  219. * Look up an address property in a node and return it as an address.
  220. * The property must hold one address with a length. This is only tested
  221. * on 32-bit machines.
  222. *
  223. * @param blob FDT blob
  224. * @param node node to examine
  225. * @param prop_name name of property to find
  226. * @return address, if found, or FDT_ADDR_T_NONE if not
  227. */
  228. fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
  229. const char *prop_name, fdt_size_t *sizep);
  230. /**
  231. * Look up a 32-bit integer property in a node and return it. The property
  232. * must have at least 4 bytes of data. The value of the first cell is
  233. * returned.
  234. *
  235. * @param blob FDT blob
  236. * @param node node to examine
  237. * @param prop_name name of property to find
  238. * @param default_val default value to return if the property is not found
  239. * @return integer value, if found, or default_val if not
  240. */
  241. s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
  242. s32 default_val);
  243. /**
  244. * Look up a 64-bit integer property in a node and return it. The property
  245. * must have at least 8 bytes of data (2 cells). The first two cells are
  246. * concatenated to form a 8 bytes value, where the first cell is top half and
  247. * the second cell is bottom half.
  248. *
  249. * @param blob FDT blob
  250. * @param node node to examine
  251. * @param prop_name name of property to find
  252. * @param default_val default value to return if the property is not found
  253. * @return integer value, if found, or default_val if not
  254. */
  255. uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
  256. uint64_t default_val);
  257. /**
  258. * Checks whether a node is enabled.
  259. * This looks for a 'status' property. If this exists, then returns 1 if
  260. * the status is 'ok' and 0 otherwise. If there is no status property,
  261. * it returns 1 on the assumption that anything mentioned should be enabled
  262. * by default.
  263. *
  264. * @param blob FDT blob
  265. * @param node node to examine
  266. * @return integer value 0 (not enabled) or 1 (enabled)
  267. */
  268. int fdtdec_get_is_enabled(const void *blob, int node);
  269. /**
  270. * Make sure we have a valid fdt available to control U-Boot.
  271. *
  272. * If not, a message is printed to the console if the console is ready.
  273. *
  274. * @return 0 if all ok, -1 if not
  275. */
  276. int fdtdec_prepare_fdt(void);
  277. /**
  278. * Checks that we have a valid fdt available to control U-Boot.
  279. * However, if not then for the moment nothing is done, since this function
  280. * is called too early to panic().
  281. *
  282. * @returns 0
  283. */
  284. int fdtdec_check_fdt(void);
  285. /**
  286. * Find the nodes for a peripheral and return a list of them in the correct
  287. * order. This is used to enumerate all the peripherals of a certain type.
  288. *
  289. * To use this, optionally set up a /aliases node with alias properties for
  290. * a peripheral. For example, for usb you could have:
  291. *
  292. * aliases {
  293. * usb0 = "/ehci@c5008000";
  294. * usb1 = "/ehci@c5000000";
  295. * };
  296. *
  297. * Pass "usb" as the name to this function and will return a list of two
  298. * nodes offsets: /ehci@c5008000 and ehci@c5000000.
  299. *
  300. * All nodes returned will match the compatible ID, as it is assumed that
  301. * all peripherals use the same driver.
  302. *
  303. * If no alias node is found, then the node list will be returned in the
  304. * order found in the fdt. If the aliases mention a node which doesn't
  305. * exist, then this will be ignored. If nodes are found with no aliases,
  306. * they will be added in any order.
  307. *
  308. * If there is a gap in the aliases, then this function return a 0 node at
  309. * that position. The return value will also count these gaps.
  310. *
  311. * This function checks node properties and will not return nodes which are
  312. * marked disabled (status = "disabled").
  313. *
  314. * @param blob FDT blob to use
  315. * @param name Root name of alias to search for
  316. * @param id Compatible ID to look for
  317. * @param node_list Place to put list of found nodes
  318. * @param maxcount Maximum number of nodes to find
  319. * @return number of nodes found on success, FTD_ERR_... on error
  320. */
  321. int fdtdec_find_aliases_for_id(const void *blob, const char *name,
  322. enum fdt_compat_id id, int *node_list, int maxcount);
  323. /*
  324. * This function is similar to fdtdec_find_aliases_for_id() except that it
  325. * adds to the node_list that is passed in. Any 0 elements are considered
  326. * available for allocation - others are considered already used and are
  327. * skipped.
  328. *
  329. * You can use this by calling fdtdec_find_aliases_for_id() with an
  330. * uninitialised array, then setting the elements that are returned to -1,
  331. * say, then calling this function, perhaps with a different compat id.
  332. * Any elements you get back that are >0 are new nodes added by the call
  333. * to this function.
  334. *
  335. * Note that if you have some nodes with aliases and some without, you are
  336. * sailing close to the wind. The call to fdtdec_find_aliases_for_id() with
  337. * one compat_id may fill in positions for which you have aliases defined
  338. * for another compat_id. When you later call *this* function with the second
  339. * compat_id, the alias positions may already be used. A debug warning may
  340. * be generated in this case, but it is safest to define aliases for all
  341. * nodes when you care about the ordering.
  342. */
  343. int fdtdec_add_aliases_for_id(const void *blob, const char *name,
  344. enum fdt_compat_id id, int *node_list, int maxcount);
  345. /**
  346. * Get the alias sequence number of a node
  347. *
  348. * This works out whether a node is pointed to by an alias, and if so, the
  349. * sequence number of that alias. Aliases are of the form <base><num> where
  350. * <num> is the sequence number. For example spi2 would be sequence number
  351. * 2.
  352. *
  353. * @param blob Device tree blob (if NULL, then error is returned)
  354. * @param base Base name for alias (before the underscore)
  355. * @param node Node to look up
  356. * @param seqp This is set to the sequence number if one is found,
  357. * but otherwise the value is left alone
  358. * @return 0 if a sequence was found, -ve if not
  359. */
  360. int fdtdec_get_alias_seq(const void *blob, const char *base, int node,
  361. int *seqp);
  362. /**
  363. * Get the offset of the given alias node
  364. *
  365. * This looks up an alias in /aliases then finds the offset of that node.
  366. *
  367. * @param blob Device tree blob (if NULL, then error is returned)
  368. * @param name Alias name, e.g. "console"
  369. * @return Node offset referred to by that alias, or -ve FDT_ERR_...
  370. */
  371. int fdtdec_get_alias_node(const void *blob, const char *name);
  372. /**
  373. * Get the offset of the given chosen node
  374. *
  375. * This looks up a property in /chosen containing the path to another node,
  376. * then finds the offset of that node.
  377. *
  378. * @param blob Device tree blob (if NULL, then error is returned)
  379. * @param name Property name, e.g. "stdout-path"
  380. * @return Node offset referred to by that chosen node, or -ve FDT_ERR_...
  381. */
  382. int fdtdec_get_chosen_node(const void *blob, const char *name);
  383. /*
  384. * Get the name for a compatible ID
  385. *
  386. * @param id Compatible ID to look for
  387. * @return compatible string for that id
  388. */
  389. const char *fdtdec_get_compatible(enum fdt_compat_id id);
  390. /* Look up a phandle and follow it to its node. Then return the offset
  391. * of that node.
  392. *
  393. * @param blob FDT blob
  394. * @param node node to examine
  395. * @param prop_name name of property to find
  396. * @return node offset if found, -ve error code on error
  397. */
  398. int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name);
  399. /**
  400. * Look up a property in a node and return its contents in an integer
  401. * array of given length. The property must have at least enough data for
  402. * the array (4*count bytes). It may have more, but this will be ignored.
  403. *
  404. * @param blob FDT blob
  405. * @param node node to examine
  406. * @param prop_name name of property to find
  407. * @param array array to fill with data
  408. * @param count number of array elements
  409. * @return 0 if ok, or -FDT_ERR_NOTFOUND if the property is not found,
  410. * or -FDT_ERR_BADLAYOUT if not enough data
  411. */
  412. int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
  413. u32 *array, int count);
  414. /**
  415. * Look up a property in a node and return its contents in an integer
  416. * array of given length. The property must exist but may have less data that
  417. * expected (4*count bytes). It may have more, but this will be ignored.
  418. *
  419. * @param blob FDT blob
  420. * @param node node to examine
  421. * @param prop_name name of property to find
  422. * @param array array to fill with data
  423. * @param count number of array elements
  424. * @return number of array elements if ok, or -FDT_ERR_NOTFOUND if the
  425. * property is not found
  426. */
  427. int fdtdec_get_int_array_count(const void *blob, int node,
  428. const char *prop_name, u32 *array, int count);
  429. /**
  430. * Look up a property in a node and return a pointer to its contents as a
  431. * unsigned int array of given length. The property must have at least enough
  432. * data for the array ('count' cells). It may have more, but this will be
  433. * ignored. The data is not copied.
  434. *
  435. * Note that you must access elements of the array with fdt32_to_cpu(),
  436. * since the elements will be big endian even on a little endian machine.
  437. *
  438. * @param blob FDT blob
  439. * @param node node to examine
  440. * @param prop_name name of property to find
  441. * @param count number of array elements
  442. * @return pointer to array if found, or NULL if the property is not
  443. * found or there is not enough data
  444. */
  445. const u32 *fdtdec_locate_array(const void *blob, int node,
  446. const char *prop_name, int count);
  447. /**
  448. * Look up a boolean property in a node and return it.
  449. *
  450. * A boolean properly is true if present in the device tree and false if not
  451. * present, regardless of its value.
  452. *
  453. * @param blob FDT blob
  454. * @param node node to examine
  455. * @param prop_name name of property to find
  456. * @return 1 if the properly is present; 0 if it isn't present
  457. */
  458. int fdtdec_get_bool(const void *blob, int node, const char *prop_name);
  459. /**
  460. * Decode a single GPIOs from an FDT.
  461. *
  462. * If the property is not found, then the GPIO structure will still be
  463. * initialised, with gpio set to FDT_GPIO_NONE. This makes it easy to
  464. * provide optional GPIOs.
  465. *
  466. * @param blob FDT blob to use
  467. * @param node Node to look at
  468. * @param prop_name Node property name
  469. * @param gpio gpio elements to fill from FDT
  470. * @return 0 if ok, -FDT_ERR_NOTFOUND if the property is missing.
  471. */
  472. int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name,
  473. struct fdt_gpio_state *gpio);
  474. /**
  475. * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no
  476. * terminating item.
  477. *
  478. * @param blob FDT blob to use
  479. * @param node Node to look at
  480. * @param prop_name Node property name
  481. * @param gpio Array of gpio elements to fill from FDT. This will be
  482. * untouched if either 0 or an error is returned
  483. * @param max_count Maximum number of elements allowed
  484. * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would
  485. * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing.
  486. */
  487. int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name,
  488. struct fdt_gpio_state *gpio, int max_count);
  489. /**
  490. * Set up a GPIO pin according to the provided gpio information. At present this
  491. * just requests the GPIO.
  492. *
  493. * If the gpio is FDT_GPIO_NONE, no action is taken. This makes it easy to
  494. * deal with optional GPIOs.
  495. *
  496. * @param gpio GPIO info to use for set up
  497. * @return 0 if all ok or gpio was FDT_GPIO_NONE; -1 on error
  498. */
  499. int fdtdec_setup_gpio(struct fdt_gpio_state *gpio);
  500. /**
  501. * Look in the FDT for a config item with the given name and return its value
  502. * as a 32-bit integer. The property must have at least 4 bytes of data. The
  503. * value of the first cell is returned.
  504. *
  505. * @param blob FDT blob to use
  506. * @param prop_name Node property name
  507. * @param default_val default value to return if the property is not found
  508. * @return integer value, if found, or default_val if not
  509. */
  510. int fdtdec_get_config_int(const void *blob, const char *prop_name,
  511. int default_val);
  512. /**
  513. * Look in the FDT for a config item with the given name
  514. * and return whether it exists.
  515. *
  516. * @param blob FDT blob
  517. * @param prop_name property name to look up
  518. * @return 1, if it exists, or 0 if not
  519. */
  520. int fdtdec_get_config_bool(const void *blob, const char *prop_name);
  521. /**
  522. * Look in the FDT for a config item with the given name and return its value
  523. * as a string.
  524. *
  525. * @param blob FDT blob
  526. * @param prop_name property name to look up
  527. * @returns property string, NULL on error.
  528. */
  529. char *fdtdec_get_config_string(const void *blob, const char *prop_name);
  530. /*
  531. * Look up a property in a node and return its contents in a byte
  532. * array of given length. The property must have at least enough data for
  533. * the array (count bytes). It may have more, but this will be ignored.
  534. *
  535. * @param blob FDT blob
  536. * @param node node to examine
  537. * @param prop_name name of property to find
  538. * @param array array to fill with data
  539. * @param count number of array elements
  540. * @return 0 if ok, or -FDT_ERR_MISSING if the property is not found,
  541. * or -FDT_ERR_BADLAYOUT if not enough data
  542. */
  543. int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
  544. u8 *array, int count);
  545. /**
  546. * Look up a property in a node and return a pointer to its contents as a
  547. * byte array of given length. The property must have at least enough data
  548. * for the array (count bytes). It may have more, but this will be ignored.
  549. * The data is not copied.
  550. *
  551. * @param blob FDT blob
  552. * @param node node to examine
  553. * @param prop_name name of property to find
  554. * @param count number of array elements
  555. * @return pointer to byte array if found, or NULL if the property is not
  556. * found or there is not enough data
  557. */
  558. const u8 *fdtdec_locate_byte_array(const void *blob, int node,
  559. const char *prop_name, int count);
  560. /**
  561. * Look up a property in a node which contains a memory region address and
  562. * size. Then return a pointer to this address.
  563. *
  564. * The property must hold one address with a length. This is only tested on
  565. * 32-bit machines.
  566. *
  567. * @param blob FDT blob
  568. * @param node node to examine
  569. * @param prop_name name of property to find
  570. * @param ptrp returns pointer to region, or NULL if no address
  571. * @param size returns size of region
  572. * @return 0 if ok, -1 on error (propery not found)
  573. */
  574. int fdtdec_decode_region(const void *blob, int node,
  575. const char *prop_name, void **ptrp, size_t *size);
  576. /* A flash map entry, containing an offset and length */
  577. struct fmap_entry {
  578. uint32_t offset;
  579. uint32_t length;
  580. };
  581. /**
  582. * Read a flash entry from the fdt
  583. *
  584. * @param blob FDT blob
  585. * @param node Offset of node to read
  586. * @param name Name of node being read
  587. * @param entry Place to put offset and size of this node
  588. * @return 0 if ok, -ve on error
  589. */
  590. int fdtdec_read_fmap_entry(const void *blob, int node, const char *name,
  591. struct fmap_entry *entry);
  592. /**
  593. * Obtain an indexed resource from a device property.
  594. *
  595. * @param fdt FDT blob
  596. * @param node node to examine
  597. * @param property name of the property to parse
  598. * @param index index of the resource to retrieve
  599. * @param res returns the resource
  600. * @return 0 if ok, negative on error
  601. */
  602. int fdt_get_resource(const void *fdt, int node, const char *property,
  603. unsigned int index, struct fdt_resource *res);
  604. /**
  605. * Obtain a named resource from a device property.
  606. *
  607. * Look up the index of the name in a list of strings and return the resource
  608. * at that index.
  609. *
  610. * @param fdt FDT blob
  611. * @param node node to examine
  612. * @param property name of the property to parse
  613. * @param prop_names name of the property containing the list of names
  614. * @param name the name of the entry to look up
  615. * @param res returns the resource
  616. */
  617. int fdt_get_named_resource(const void *fdt, int node, const char *property,
  618. const char *prop_names, const char *name,
  619. struct fdt_resource *res);
  620. /**
  621. * Look at the reg property of a device node that represents a PCI device
  622. * and parse the bus, device and function number from it.
  623. *
  624. * @param fdt FDT blob
  625. * @param node node to examine
  626. * @param bdf returns bus, device, function triplet
  627. * @return 0 if ok, negative on error
  628. */
  629. int fdtdec_pci_get_bdf(const void *fdt, int node, int *bdf);
  630. #endif