README 142 KB

12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364656667686970717273747576777879808182838485868788899091929394959697989910010110210310410510610710810911011111211311411511611711811912012112212312412512612712812913013113213313413513613713813914014114214314414514614714814915015115215315415515615715815916016116216316416516616716816917017117217317417517617717817918018118218318418518618718818919019119219319419519619719819920020120220320420520620720820921021121221321421521621721821922022122222322422522622722822923023123223323423523623723823924024124224324424524624724824925025125225325425525625725825926026126226326426526626726826927027127227327427527627727827928028128228328428528628728828929029129229329429529629729829930030130230330430530630730830931031131231331431531631731831932032132232332432532632732832933033133233333433533633733833934034134234334434534634734834935035135235335435535635735835936036136236336436536636736836937037137237337437537637737837938038138238338438538638738838939039139239339439539639739839940040140240340440540640740840941041141241341441541641741841942042142242342442542642742842943043143243343443543643743843944044144244344444544644744844945045145245345445545645745845946046146246346446546646746846947047147247347447547647747847948048148248348448548648748848949049149249349449549649749849950050150250350450550650750850951051151251351451551651751851952052152252352452552652752852953053153253353453553653753853954054154254354454554654754854955055155255355455555655755855956056156256356456556656756856957057157257357457557657757857958058158258358458558658758858959059159259359459559659759859960060160260360460560660760860961061161261361461561661761861962062162262362462562662762862963063163263363463563663763863964064164264364464564664764864965065165265365465565665765865966066166266366466566666766866967067167267367467567667767867968068168268368468568668768868969069169269369469569669769869970070170270370470570670770870971071171271371471571671771871972072172272372472572672772872973073173273373473573673773873974074174274374474574674774874975075175275375475575675775875976076176276376476576676776876977077177277377477577677777877978078178278378478578678778878979079179279379479579679779879980080180280380480580680780880981081181281381481581681781881982082182282382482582682782882983083183283383483583683783883984084184284384484584684784884985085185285385485585685785885986086186286386486586686786886987087187287387487587687787887988088188288388488588688788888989089189289389489589689789889990090190290390490590690790890991091191291391491591691791891992092192292392492592692792892993093193293393493593693793893994094194294394494594694794894995095195295395495595695795895996096196296396496596696796896997097197297397497597697797897998098198298398498598698798898999099199299399499599699799899910001001100210031004100510061007100810091010101110121013101410151016101710181019102010211022102310241025102610271028102910301031103210331034103510361037103810391040104110421043104410451046104710481049105010511052105310541055105610571058105910601061106210631064106510661067106810691070107110721073107410751076107710781079108010811082108310841085108610871088108910901091109210931094109510961097109810991100110111021103110411051106110711081109111011111112111311141115111611171118111911201121112211231124112511261127112811291130113111321133113411351136113711381139114011411142114311441145114611471148114911501151115211531154115511561157115811591160116111621163116411651166116711681169117011711172117311741175117611771178117911801181118211831184118511861187118811891190119111921193119411951196119711981199120012011202120312041205120612071208120912101211121212131214121512161217121812191220122112221223122412251226122712281229123012311232123312341235123612371238123912401241124212431244124512461247124812491250125112521253125412551256125712581259126012611262126312641265126612671268126912701271127212731274127512761277127812791280128112821283128412851286128712881289129012911292129312941295129612971298129913001301130213031304130513061307130813091310131113121313131413151316131713181319132013211322132313241325132613271328132913301331133213331334133513361337133813391340134113421343134413451346134713481349135013511352135313541355135613571358135913601361136213631364136513661367136813691370137113721373137413751376137713781379138013811382138313841385138613871388138913901391139213931394139513961397139813991400140114021403140414051406140714081409141014111412141314141415141614171418141914201421142214231424142514261427142814291430143114321433143414351436143714381439144014411442144314441445144614471448144914501451145214531454145514561457145814591460146114621463146414651466146714681469147014711472147314741475147614771478147914801481148214831484148514861487148814891490149114921493149414951496149714981499150015011502150315041505150615071508150915101511151215131514151515161517151815191520152115221523152415251526152715281529153015311532153315341535153615371538153915401541154215431544154515461547154815491550155115521553155415551556155715581559156015611562156315641565156615671568156915701571157215731574157515761577157815791580158115821583158415851586158715881589159015911592159315941595159615971598159916001601160216031604160516061607160816091610161116121613161416151616161716181619162016211622162316241625162616271628162916301631163216331634163516361637163816391640164116421643164416451646164716481649165016511652165316541655165616571658165916601661166216631664166516661667166816691670167116721673167416751676167716781679168016811682168316841685168616871688168916901691169216931694169516961697169816991700170117021703170417051706170717081709171017111712171317141715171617171718171917201721172217231724172517261727172817291730173117321733173417351736173717381739174017411742174317441745174617471748174917501751175217531754175517561757175817591760176117621763176417651766176717681769177017711772177317741775177617771778177917801781178217831784178517861787178817891790179117921793179417951796179717981799180018011802180318041805180618071808180918101811181218131814181518161817181818191820182118221823182418251826182718281829183018311832183318341835183618371838183918401841184218431844184518461847184818491850185118521853185418551856185718581859186018611862186318641865186618671868186918701871187218731874187518761877187818791880188118821883188418851886188718881889189018911892189318941895189618971898189919001901190219031904190519061907190819091910191119121913191419151916191719181919192019211922192319241925192619271928192919301931193219331934193519361937193819391940194119421943194419451946194719481949195019511952195319541955195619571958195919601961196219631964196519661967196819691970197119721973197419751976197719781979198019811982198319841985198619871988198919901991199219931994199519961997199819992000200120022003200420052006200720082009201020112012201320142015201620172018201920202021202220232024202520262027202820292030203120322033203420352036203720382039204020412042204320442045204620472048204920502051205220532054205520562057205820592060206120622063206420652066206720682069207020712072207320742075207620772078207920802081208220832084208520862087208820892090209120922093209420952096209720982099210021012102210321042105210621072108210921102111211221132114211521162117211821192120212121222123212421252126212721282129213021312132213321342135213621372138213921402141214221432144214521462147214821492150215121522153215421552156215721582159216021612162216321642165216621672168216921702171217221732174217521762177217821792180218121822183218421852186218721882189219021912192219321942195219621972198219922002201220222032204220522062207220822092210221122122213221422152216221722182219222022212222222322242225222622272228222922302231223222332234223522362237223822392240224122422243224422452246224722482249225022512252225322542255225622572258225922602261226222632264226522662267226822692270227122722273227422752276227722782279228022812282228322842285228622872288228922902291229222932294229522962297229822992300230123022303230423052306230723082309231023112312231323142315231623172318231923202321232223232324232523262327232823292330233123322333233423352336233723382339234023412342234323442345234623472348234923502351235223532354235523562357235823592360236123622363236423652366236723682369237023712372237323742375237623772378237923802381238223832384238523862387238823892390239123922393239423952396239723982399240024012402240324042405240624072408240924102411241224132414241524162417241824192420242124222423242424252426242724282429243024312432243324342435243624372438243924402441244224432444244524462447244824492450245124522453245424552456245724582459246024612462246324642465246624672468246924702471247224732474247524762477247824792480248124822483248424852486248724882489249024912492249324942495249624972498249925002501250225032504250525062507250825092510251125122513251425152516251725182519252025212522252325242525252625272528252925302531253225332534253525362537253825392540254125422543254425452546254725482549255025512552255325542555255625572558255925602561256225632564256525662567256825692570257125722573257425752576257725782579258025812582258325842585258625872588258925902591259225932594259525962597259825992600260126022603260426052606260726082609261026112612261326142615261626172618261926202621262226232624262526262627262826292630263126322633263426352636263726382639264026412642264326442645264626472648264926502651265226532654265526562657265826592660266126622663266426652666266726682669267026712672267326742675267626772678267926802681268226832684268526862687268826892690269126922693269426952696269726982699270027012702270327042705270627072708270927102711271227132714271527162717271827192720272127222723272427252726272727282729273027312732273327342735273627372738273927402741274227432744274527462747274827492750275127522753275427552756275727582759276027612762276327642765276627672768276927702771277227732774277527762777277827792780278127822783278427852786278727882789279027912792279327942795279627972798279928002801280228032804280528062807280828092810281128122813281428152816281728182819282028212822282328242825282628272828282928302831283228332834283528362837283828392840284128422843284428452846284728482849285028512852285328542855285628572858285928602861286228632864286528662867286828692870287128722873287428752876287728782879288028812882288328842885288628872888288928902891289228932894289528962897289828992900290129022903290429052906290729082909291029112912291329142915291629172918291929202921292229232924292529262927292829292930293129322933293429352936293729382939294029412942294329442945294629472948294929502951295229532954295529562957295829592960296129622963296429652966296729682969297029712972297329742975297629772978297929802981298229832984298529862987298829892990299129922993299429952996299729982999300030013002300330043005300630073008300930103011301230133014301530163017301830193020302130223023302430253026302730283029303030313032303330343035303630373038303930403041304230433044304530463047304830493050305130523053305430553056305730583059306030613062306330643065306630673068306930703071307230733074307530763077307830793080308130823083308430853086308730883089309030913092309330943095309630973098309931003101310231033104310531063107310831093110311131123113311431153116311731183119312031213122312331243125312631273128312931303131313231333134313531363137313831393140314131423143314431453146314731483149315031513152315331543155315631573158315931603161316231633164316531663167316831693170317131723173317431753176317731783179318031813182318331843185318631873188318931903191319231933194319531963197319831993200320132023203320432053206320732083209321032113212321332143215321632173218321932203221322232233224322532263227322832293230323132323233323432353236323732383239324032413242324332443245324632473248324932503251325232533254325532563257325832593260326132623263326432653266326732683269327032713272327332743275327632773278327932803281328232833284328532863287328832893290329132923293329432953296329732983299330033013302330333043305330633073308330933103311331233133314331533163317331833193320332133223323332433253326332733283329333033313332333333343335333633373338333933403341334233433344334533463347334833493350335133523353335433553356335733583359336033613362336333643365336633673368336933703371337233733374337533763377337833793380338133823383338433853386338733883389339033913392339333943395339633973398339934003401340234033404340534063407340834093410341134123413341434153416341734183419342034213422342334243425342634273428342934303431343234333434343534363437343834393440344134423443344434453446344734483449345034513452345334543455345634573458345934603461346234633464346534663467346834693470347134723473347434753476347734783479348034813482348334843485348634873488348934903491349234933494349534963497349834993500350135023503350435053506350735083509351035113512351335143515351635173518351935203521352235233524352535263527352835293530353135323533353435353536353735383539354035413542354335443545354635473548354935503551355235533554355535563557355835593560356135623563356435653566356735683569357035713572357335743575357635773578357935803581358235833584358535863587358835893590359135923593359435953596359735983599360036013602360336043605360636073608360936103611361236133614361536163617361836193620362136223623362436253626362736283629363036313632363336343635363636373638363936403641364236433644364536463647364836493650365136523653365436553656365736583659366036613662366336643665366636673668366936703671367236733674367536763677367836793680368136823683368436853686368736883689369036913692369336943695369636973698369937003701370237033704370537063707370837093710371137123713371437153716371737183719372037213722372337243725372637273728372937303731373237333734373537363737373837393740374137423743374437453746374737483749375037513752375337543755375637573758375937603761376237633764376537663767376837693770377137723773377437753776377737783779378037813782378337843785378637873788378937903791379237933794379537963797379837993800380138023803380438053806380738083809381038113812381338143815381638173818381938203821382238233824382538263827382838293830383138323833383438353836383738383839384038413842384338443845384638473848384938503851385238533854385538563857385838593860386138623863386438653866386738683869387038713872387338743875387638773878387938803881388238833884388538863887388838893890389138923893389438953896389738983899390039013902390339043905390639073908390939103911391239133914391539163917391839193920392139223923392439253926392739283929393039313932393339343935393639373938393939403941394239433944394539463947394839493950395139523953395439553956395739583959396039613962396339643965396639673968396939703971397239733974397539763977397839793980398139823983398439853986398739883989399039913992399339943995399639973998399940004001400240034004400540064007400840094010401140124013401440154016401740184019402040214022402340244025402640274028402940304031403240334034403540364037403840394040404140424043404440454046404740484049405040514052405340544055405640574058405940604061406240634064406540664067406840694070407140724073407440754076407740784079408040814082408340844085408640874088408940904091409240934094409540964097409840994100410141024103410441054106410741084109411041114112411341144115411641174118411941204121412241234124412541264127412841294130413141324133413441354136413741384139414041414142414341444145414641474148414941504151415241534154415541564157415841594160416141624163416441654166416741684169417041714172417341744175417641774178417941804181418241834184418541864187418841894190419141924193419441954196419741984199420042014202420342044205420642074208
  1. #
  2. # (C) Copyright 2000 - 2009
  3. # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  4. #
  5. # See file CREDITS for list of people who contributed to this
  6. # project.
  7. #
  8. # This program is free software; you can redistribute it and/or
  9. # modify it under the terms of the GNU General Public License as
  10. # published by the Free Software Foundation; either version 2 of
  11. # the License, or (at your option) any later version.
  12. #
  13. # This program is distributed in the hope that it will be useful,
  14. # but WITHOUT ANY WARRANTY; without even the implied warranty of
  15. # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16. # GNU General Public License for more details.
  17. #
  18. # You should have received a copy of the GNU General Public License
  19. # along with this program; if not, write to the Free Software
  20. # Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  21. # MA 02111-1307 USA
  22. #
  23. Summary:
  24. ========
  25. This directory contains the source code for U-Boot, a boot loader for
  26. Embedded boards based on PowerPC, ARM, MIPS and several other
  27. processors, which can be installed in a boot ROM and used to
  28. initialize and test the hardware or to download and run application
  29. code.
  30. The development of U-Boot is closely related to Linux: some parts of
  31. the source code originate in the Linux source tree, we have some
  32. header files in common, and special provision has been made to
  33. support booting of Linux images.
  34. Some attention has been paid to make this software easily
  35. configurable and extendable. For instance, all monitor commands are
  36. implemented with the same call interface, so that it's very easy to
  37. add new commands. Also, instead of permanently adding rarely used
  38. code (for instance hardware test utilities) to the monitor, you can
  39. load and run it dynamically.
  40. Status:
  41. =======
  42. In general, all boards for which a configuration option exists in the
  43. Makefile have been tested to some extent and can be considered
  44. "working". In fact, many of them are used in production systems.
  45. In case of problems see the CHANGELOG and CREDITS files to find out
  46. who contributed the specific port. The MAINTAINERS file lists board
  47. maintainers.
  48. Where to get help:
  49. ==================
  50. In case you have questions about, problems with or contributions for
  51. U-Boot you should send a message to the U-Boot mailing list at
  52. <u-boot@lists.denx.de>. There is also an archive of previous traffic
  53. on the mailing list - please search the archive before asking FAQ's.
  54. Please see http://lists.denx.de/pipermail/u-boot and
  55. http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
  56. Where to get source code:
  57. =========================
  58. The U-Boot source code is maintained in the git repository at
  59. git://www.denx.de/git/u-boot.git ; you can browse it online at
  60. http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
  61. The "snapshot" links on this page allow you to download tarballs of
  62. any version you might be interested in. Official releases are also
  63. available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
  64. directory.
  65. Pre-built (and tested) images are available from
  66. ftp://ftp.denx.de/pub/u-boot/images/
  67. Where we come from:
  68. ===================
  69. - start from 8xxrom sources
  70. - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
  71. - clean up code
  72. - make it easier to add custom boards
  73. - make it possible to add other [PowerPC] CPUs
  74. - extend functions, especially:
  75. * Provide extended interface to Linux boot loader
  76. * S-Record download
  77. * network boot
  78. * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
  79. - create ARMBoot project (http://sourceforge.net/projects/armboot)
  80. - add other CPU families (starting with ARM)
  81. - create U-Boot project (http://sourceforge.net/projects/u-boot)
  82. - current project page: see http://www.denx.de/wiki/U-Boot
  83. Names and Spelling:
  84. ===================
  85. The "official" name of this project is "Das U-Boot". The spelling
  86. "U-Boot" shall be used in all written text (documentation, comments
  87. in source files etc.). Example:
  88. This is the README file for the U-Boot project.
  89. File names etc. shall be based on the string "u-boot". Examples:
  90. include/asm-ppc/u-boot.h
  91. #include <asm/u-boot.h>
  92. Variable names, preprocessor constants etc. shall be either based on
  93. the string "u_boot" or on "U_BOOT". Example:
  94. U_BOOT_VERSION u_boot_logo
  95. IH_OS_U_BOOT u_boot_hush_start
  96. Versioning:
  97. ===========
  98. U-Boot uses a 3 level version number containing a version, a
  99. sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2",
  100. sub-version "34", and patchlevel "4".
  101. The patchlevel is used to indicate certain stages of development
  102. between released versions, i. e. officially released versions of
  103. U-Boot will always have a patchlevel of "0".
  104. Directory Hierarchy:
  105. ====================
  106. - api Machine/arch independent API for external apps
  107. - board Board dependent files
  108. - common Misc architecture independent functions
  109. - cpu CPU specific files
  110. - 74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
  111. - arm720t Files specific to ARM 720 CPUs
  112. - arm920t Files specific to ARM 920 CPUs
  113. - at91rm9200 Files specific to Atmel AT91RM9200 CPU
  114. - imx Files specific to Freescale MC9328 i.MX CPUs
  115. - s3c24x0 Files specific to Samsung S3C24X0 CPUs
  116. - arm925t Files specific to ARM 925 CPUs
  117. - arm926ejs Files specific to ARM 926 CPUs
  118. - arm1136 Files specific to ARM 1136 CPUs
  119. - at32ap Files specific to Atmel AVR32 AP CPUs
  120. - blackfin Files specific to Analog Devices Blackfin CPUs
  121. - i386 Files specific to i386 CPUs
  122. - ixp Files specific to Intel XScale IXP CPUs
  123. - leon2 Files specific to Gaisler LEON2 SPARC CPU
  124. - leon3 Files specific to Gaisler LEON3 SPARC CPU
  125. - mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
  126. - mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
  127. - mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
  128. - mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
  129. - mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
  130. - mips Files specific to MIPS CPUs
  131. - mpc5xx Files specific to Freescale MPC5xx CPUs
  132. - mpc5xxx Files specific to Freescale MPC5xxx CPUs
  133. - mpc8xx Files specific to Freescale MPC8xx CPUs
  134. - mpc8220 Files specific to Freescale MPC8220 CPUs
  135. - mpc824x Files specific to Freescale MPC824x CPUs
  136. - mpc8260 Files specific to Freescale MPC8260 CPUs
  137. - mpc85xx Files specific to Freescale MPC85xx CPUs
  138. - nios Files specific to Altera NIOS CPUs
  139. - nios2 Files specific to Altera Nios-II CPUs
  140. - ppc4xx Files specific to AMCC PowerPC 4xx CPUs
  141. - pxa Files specific to Intel XScale PXA CPUs
  142. - s3c44b0 Files specific to Samsung S3C44B0 CPUs
  143. - sa1100 Files specific to Intel StrongARM SA1100 CPUs
  144. - disk Code for disk drive partition handling
  145. - doc Documentation (don't expect too much)
  146. - drivers Commonly used device drivers
  147. - examples Example code for standalone applications, etc.
  148. - fs Filesystem code (cramfs, ext2, jffs2, etc.)
  149. - include Header Files
  150. - lib_arm Files generic to ARM architecture
  151. - lib_avr32 Files generic to AVR32 architecture
  152. - lib_blackfin Files generic to Blackfin architecture
  153. - lib_generic Files generic to all architectures
  154. - lib_i386 Files generic to i386 architecture
  155. - lib_m68k Files generic to m68k architecture
  156. - lib_microblaze Files generic to microblaze architecture
  157. - lib_mips Files generic to MIPS architecture
  158. - lib_nios Files generic to NIOS architecture
  159. - lib_nios2 Files generic to NIOS2 architecture
  160. - lib_ppc Files generic to PowerPC architecture
  161. - lib_sh Files generic to SH architecture
  162. - lib_sparc Files generic to SPARC architecture
  163. - libfdt Library files to support flattened device trees
  164. - net Networking code
  165. - post Power On Self Test
  166. - rtc Real Time Clock drivers
  167. - tools Tools to build S-Record or U-Boot images, etc.
  168. Software Configuration:
  169. =======================
  170. Configuration is usually done using C preprocessor defines; the
  171. rationale behind that is to avoid dead code whenever possible.
  172. There are two classes of configuration variables:
  173. * Configuration _OPTIONS_:
  174. These are selectable by the user and have names beginning with
  175. "CONFIG_".
  176. * Configuration _SETTINGS_:
  177. These depend on the hardware etc. and should not be meddled with if
  178. you don't know what you're doing; they have names beginning with
  179. "CONFIG_SYS_".
  180. Later we will add a configuration tool - probably similar to or even
  181. identical to what's used for the Linux kernel. Right now, we have to
  182. do the configuration by hand, which means creating some symbolic
  183. links and editing some configuration files. We use the TQM8xxL boards
  184. as an example here.
  185. Selection of Processor Architecture and Board Type:
  186. ---------------------------------------------------
  187. For all supported boards there are ready-to-use default
  188. configurations available; just type "make <board_name>_config".
  189. Example: For a TQM823L module type:
  190. cd u-boot
  191. make TQM823L_config
  192. For the Cogent platform, you need to specify the CPU type as well;
  193. e.g. "make cogent_mpc8xx_config". And also configure the cogent
  194. directory according to the instructions in cogent/README.
  195. Configuration Options:
  196. ----------------------
  197. Configuration depends on the combination of board and CPU type; all
  198. such information is kept in a configuration file
  199. "include/configs/<board_name>.h".
  200. Example: For a TQM823L module, all configuration settings are in
  201. "include/configs/TQM823L.h".
  202. Many of the options are named exactly as the corresponding Linux
  203. kernel configuration options. The intention is to make it easier to
  204. build a config tool - later.
  205. The following options need to be configured:
  206. - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
  207. - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
  208. - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
  209. Define exactly one, e.g. CONFIG_ATSTK1002
  210. - CPU Module Type: (if CONFIG_COGENT is defined)
  211. Define exactly one of
  212. CONFIG_CMA286_60_OLD
  213. --- FIXME --- not tested yet:
  214. CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
  215. CONFIG_CMA287_23, CONFIG_CMA287_50
  216. - Motherboard Type: (if CONFIG_COGENT is defined)
  217. Define exactly one of
  218. CONFIG_CMA101, CONFIG_CMA102
  219. - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
  220. Define one or more of
  221. CONFIG_CMA302
  222. - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
  223. Define one or more of
  224. CONFIG_LCD_HEARTBEAT - update a character position on
  225. the LCD display every second with
  226. a "rotator" |\-/|\-/
  227. - Board flavour: (if CONFIG_MPC8260ADS is defined)
  228. CONFIG_ADSTYPE
  229. Possible values are:
  230. CONFIG_SYS_8260ADS - original MPC8260ADS
  231. CONFIG_SYS_8266ADS - MPC8266ADS
  232. CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
  233. CONFIG_SYS_8272ADS - MPC8272ADS
  234. - MPC824X Family Member (if CONFIG_MPC824X is defined)
  235. Define exactly one of
  236. CONFIG_MPC8240, CONFIG_MPC8245
  237. - 8xx CPU Options: (if using an MPC8xx CPU)
  238. CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
  239. get_gclk_freq() cannot work
  240. e.g. if there is no 32KHz
  241. reference PIT/RTC clock
  242. CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
  243. or XTAL/EXTAL)
  244. - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
  245. CONFIG_SYS_8xx_CPUCLK_MIN
  246. CONFIG_SYS_8xx_CPUCLK_MAX
  247. CONFIG_8xx_CPUCLK_DEFAULT
  248. See doc/README.MPC866
  249. CONFIG_SYS_MEASURE_CPUCLK
  250. Define this to measure the actual CPU clock instead
  251. of relying on the correctness of the configured
  252. values. Mostly useful for board bringup to make sure
  253. the PLL is locked at the intended frequency. Note
  254. that this requires a (stable) reference clock (32 kHz
  255. RTC clock or CONFIG_SYS_8XX_XIN)
  256. CONFIG_SYS_DELAYED_ICACHE
  257. Define this option if you want to enable the
  258. ICache only when Code runs from RAM.
  259. - Intel Monahans options:
  260. CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
  261. Defines the Monahans run mode to oscillator
  262. ratio. Valid values are 8, 16, 24, 31. The core
  263. frequency is this value multiplied by 13 MHz.
  264. CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
  265. Defines the Monahans turbo mode to oscillator
  266. ratio. Valid values are 1 (default if undefined) and
  267. 2. The core frequency as calculated above is multiplied
  268. by this value.
  269. - Linux Kernel Interface:
  270. CONFIG_CLOCKS_IN_MHZ
  271. U-Boot stores all clock information in Hz
  272. internally. For binary compatibility with older Linux
  273. kernels (which expect the clocks passed in the
  274. bd_info data to be in MHz) the environment variable
  275. "clocks_in_mhz" can be defined so that U-Boot
  276. converts clock data to MHZ before passing it to the
  277. Linux kernel.
  278. When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
  279. "clocks_in_mhz=1" is automatically included in the
  280. default environment.
  281. CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
  282. When transferring memsize parameter to linux, some versions
  283. expect it to be in bytes, others in MB.
  284. Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
  285. CONFIG_OF_LIBFDT
  286. New kernel versions are expecting firmware settings to be
  287. passed using flattened device trees (based on open firmware
  288. concepts).
  289. CONFIG_OF_LIBFDT
  290. * New libfdt-based support
  291. * Adds the "fdt" command
  292. * The bootm command automatically updates the fdt
  293. OF_CPU - The proper name of the cpus node (only required for
  294. MPC512X and MPC5xxx based boards).
  295. OF_SOC - The proper name of the soc node (only required for
  296. MPC512X and MPC5xxx based boards).
  297. OF_TBCLK - The timebase frequency.
  298. OF_STDOUT_PATH - The path to the console device
  299. boards with QUICC Engines require OF_QE to set UCC MAC
  300. addresses
  301. CONFIG_OF_BOARD_SETUP
  302. Board code has addition modification that it wants to make
  303. to the flat device tree before handing it off to the kernel
  304. CONFIG_OF_BOOT_CPU
  305. This define fills in the correct boot CPU in the boot
  306. param header, the default value is zero if undefined.
  307. CONFIG_OF_IDE_FIXUP
  308. U-Boot can detect if an IDE device is present or not.
  309. If not, and this new config option is activated, U-Boot
  310. removes the ATA node from the DTS before booting Linux,
  311. so the Linux IDE driver does not probe the device and
  312. crash. This is needed for buggy hardware (uc101) where
  313. no pull down resistor is connected to the signal IDE5V_DD7.
  314. - vxWorks boot parameters:
  315. bootvx constructs a valid bootline using the following
  316. environments variables: bootfile, ipaddr, serverip, hostname.
  317. It loads the vxWorks image pointed bootfile.
  318. CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
  319. CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
  320. CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
  321. CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
  322. CONFIG_SYS_VXWORKS_ADD_PARAMS
  323. Add it at the end of the bootline. E.g "u=username pw=secret"
  324. Note: If a "bootargs" environment is defined, it will overwride
  325. the defaults discussed just above.
  326. - Serial Ports:
  327. CONFIG_PL010_SERIAL
  328. Define this if you want support for Amba PrimeCell PL010 UARTs.
  329. CONFIG_PL011_SERIAL
  330. Define this if you want support for Amba PrimeCell PL011 UARTs.
  331. CONFIG_PL011_CLOCK
  332. If you have Amba PrimeCell PL011 UARTs, set this variable to
  333. the clock speed of the UARTs.
  334. CONFIG_PL01x_PORTS
  335. If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
  336. define this to a list of base addresses for each (supported)
  337. port. See e.g. include/configs/versatile.h
  338. - Console Interface:
  339. Depending on board, define exactly one serial port
  340. (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
  341. CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
  342. console by defining CONFIG_8xx_CONS_NONE
  343. Note: if CONFIG_8xx_CONS_NONE is defined, the serial
  344. port routines must be defined elsewhere
  345. (i.e. serial_init(), serial_getc(), ...)
  346. CONFIG_CFB_CONSOLE
  347. Enables console device for a color framebuffer. Needs following
  348. defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
  349. VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
  350. (default big endian)
  351. VIDEO_HW_RECTFILL graphic chip supports
  352. rectangle fill
  353. (cf. smiLynxEM)
  354. VIDEO_HW_BITBLT graphic chip supports
  355. bit-blit (cf. smiLynxEM)
  356. VIDEO_VISIBLE_COLS visible pixel columns
  357. (cols=pitch)
  358. VIDEO_VISIBLE_ROWS visible pixel rows
  359. VIDEO_PIXEL_SIZE bytes per pixel
  360. VIDEO_DATA_FORMAT graphic data format
  361. (0-5, cf. cfb_console.c)
  362. VIDEO_FB_ADRS framebuffer address
  363. VIDEO_KBD_INIT_FCT keyboard int fct
  364. (i.e. i8042_kbd_init())
  365. VIDEO_TSTC_FCT test char fct
  366. (i.e. i8042_tstc)
  367. VIDEO_GETC_FCT get char fct
  368. (i.e. i8042_getc)
  369. CONFIG_CONSOLE_CURSOR cursor drawing on/off
  370. (requires blink timer
  371. cf. i8042.c)
  372. CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
  373. CONFIG_CONSOLE_TIME display time/date info in
  374. upper right corner
  375. (requires CONFIG_CMD_DATE)
  376. CONFIG_VIDEO_LOGO display Linux logo in
  377. upper left corner
  378. CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
  379. linux_logo.h for logo.
  380. Requires CONFIG_VIDEO_LOGO
  381. CONFIG_CONSOLE_EXTRA_INFO
  382. additional board info beside
  383. the logo
  384. When CONFIG_CFB_CONSOLE is defined, video console is
  385. default i/o. Serial console can be forced with
  386. environment 'console=serial'.
  387. When CONFIG_SILENT_CONSOLE is defined, all console
  388. messages (by U-Boot and Linux!) can be silenced with
  389. the "silent" environment variable. See
  390. doc/README.silent for more information.
  391. - Console Baudrate:
  392. CONFIG_BAUDRATE - in bps
  393. Select one of the baudrates listed in
  394. CONFIG_SYS_BAUDRATE_TABLE, see below.
  395. CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
  396. - Console Rx buffer length
  397. With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
  398. the maximum receive buffer length for the SMC.
  399. This option is actual only for 82xx and 8xx possible.
  400. If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
  401. must be defined, to setup the maximum idle timeout for
  402. the SMC.
  403. - Interrupt driven serial port input:
  404. CONFIG_SERIAL_SOFTWARE_FIFO
  405. PPC405GP only.
  406. Use an interrupt handler for receiving data on the
  407. serial port. It also enables using hardware handshake
  408. (RTS/CTS) and UART's built-in FIFO. Set the number of
  409. bytes the interrupt driven input buffer should have.
  410. Leave undefined to disable this feature, including
  411. disable the buffer and hardware handshake.
  412. - Console UART Number:
  413. CONFIG_UART1_CONSOLE
  414. AMCC PPC4xx only.
  415. If defined internal UART1 (and not UART0) is used
  416. as default U-Boot console.
  417. - Boot Delay: CONFIG_BOOTDELAY - in seconds
  418. Delay before automatically booting the default image;
  419. set to -1 to disable autoboot.
  420. See doc/README.autoboot for these options that
  421. work with CONFIG_BOOTDELAY. None are required.
  422. CONFIG_BOOT_RETRY_TIME
  423. CONFIG_BOOT_RETRY_MIN
  424. CONFIG_AUTOBOOT_KEYED
  425. CONFIG_AUTOBOOT_PROMPT
  426. CONFIG_AUTOBOOT_DELAY_STR
  427. CONFIG_AUTOBOOT_STOP_STR
  428. CONFIG_AUTOBOOT_DELAY_STR2
  429. CONFIG_AUTOBOOT_STOP_STR2
  430. CONFIG_ZERO_BOOTDELAY_CHECK
  431. CONFIG_RESET_TO_RETRY
  432. - Autoboot Command:
  433. CONFIG_BOOTCOMMAND
  434. Only needed when CONFIG_BOOTDELAY is enabled;
  435. define a command string that is automatically executed
  436. when no character is read on the console interface
  437. within "Boot Delay" after reset.
  438. CONFIG_BOOTARGS
  439. This can be used to pass arguments to the bootm
  440. command. The value of CONFIG_BOOTARGS goes into the
  441. environment value "bootargs".
  442. CONFIG_RAMBOOT and CONFIG_NFSBOOT
  443. The value of these goes into the environment as
  444. "ramboot" and "nfsboot" respectively, and can be used
  445. as a convenience, when switching between booting from
  446. RAM and NFS.
  447. - Pre-Boot Commands:
  448. CONFIG_PREBOOT
  449. When this option is #defined, the existence of the
  450. environment variable "preboot" will be checked
  451. immediately before starting the CONFIG_BOOTDELAY
  452. countdown and/or running the auto-boot command resp.
  453. entering interactive mode.
  454. This feature is especially useful when "preboot" is
  455. automatically generated or modified. For an example
  456. see the LWMON board specific code: here "preboot" is
  457. modified when the user holds down a certain
  458. combination of keys on the (special) keyboard when
  459. booting the systems
  460. - Serial Download Echo Mode:
  461. CONFIG_LOADS_ECHO
  462. If defined to 1, all characters received during a
  463. serial download (using the "loads" command) are
  464. echoed back. This might be needed by some terminal
  465. emulations (like "cu"), but may as well just take
  466. time on others. This setting #define's the initial
  467. value of the "loads_echo" environment variable.
  468. - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
  469. CONFIG_KGDB_BAUDRATE
  470. Select one of the baudrates listed in
  471. CONFIG_SYS_BAUDRATE_TABLE, see below.
  472. - Monitor Functions:
  473. Monitor commands can be included or excluded
  474. from the build by using the #include files
  475. "config_cmd_all.h" and #undef'ing unwanted
  476. commands, or using "config_cmd_default.h"
  477. and augmenting with additional #define's
  478. for wanted commands.
  479. The default command configuration includes all commands
  480. except those marked below with a "*".
  481. CONFIG_CMD_ASKENV * ask for env variable
  482. CONFIG_CMD_BDI bdinfo
  483. CONFIG_CMD_BEDBUG * Include BedBug Debugger
  484. CONFIG_CMD_BMP * BMP support
  485. CONFIG_CMD_BSP * Board specific commands
  486. CONFIG_CMD_BOOTD bootd
  487. CONFIG_CMD_CACHE * icache, dcache
  488. CONFIG_CMD_CONSOLE coninfo
  489. CONFIG_CMD_DATE * support for RTC, date/time...
  490. CONFIG_CMD_DHCP * DHCP support
  491. CONFIG_CMD_DIAG * Diagnostics
  492. CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
  493. CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
  494. CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
  495. CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
  496. CONFIG_CMD_DTT * Digital Therm and Thermostat
  497. CONFIG_CMD_ECHO echo arguments
  498. CONFIG_CMD_EDITENV edit env variable
  499. CONFIG_CMD_EEPROM * EEPROM read/write support
  500. CONFIG_CMD_ELF * bootelf, bootvx
  501. CONFIG_CMD_SAVEENV saveenv
  502. CONFIG_CMD_FDC * Floppy Disk Support
  503. CONFIG_CMD_FAT * FAT partition support
  504. CONFIG_CMD_FDOS * Dos diskette Support
  505. CONFIG_CMD_FLASH flinfo, erase, protect
  506. CONFIG_CMD_FPGA FPGA device initialization support
  507. CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
  508. CONFIG_CMD_I2C * I2C serial bus support
  509. CONFIG_CMD_IDE * IDE harddisk support
  510. CONFIG_CMD_IMI iminfo
  511. CONFIG_CMD_IMLS List all found images
  512. CONFIG_CMD_IMMAP * IMMR dump support
  513. CONFIG_CMD_IRQ * irqinfo
  514. CONFIG_CMD_ITEST Integer/string test of 2 values
  515. CONFIG_CMD_JFFS2 * JFFS2 Support
  516. CONFIG_CMD_KGDB * kgdb
  517. CONFIG_CMD_LOADB loadb
  518. CONFIG_CMD_LOADS loads
  519. CONFIG_CMD_MD5SUM print md5 message digest
  520. (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
  521. CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
  522. loop, loopw, mtest
  523. CONFIG_CMD_MISC Misc functions like sleep etc
  524. CONFIG_CMD_MMC * MMC memory mapped support
  525. CONFIG_CMD_MII * MII utility commands
  526. CONFIG_CMD_MTDPARTS * MTD partition support
  527. CONFIG_CMD_NAND * NAND support
  528. CONFIG_CMD_NET bootp, tftpboot, rarpboot
  529. CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
  530. CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
  531. CONFIG_CMD_PCI * pciinfo
  532. CONFIG_CMD_PCMCIA * PCMCIA support
  533. CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
  534. host
  535. CONFIG_CMD_PORTIO * Port I/O
  536. CONFIG_CMD_REGINFO * Register dump
  537. CONFIG_CMD_RUN run command in env variable
  538. CONFIG_CMD_SAVES * save S record dump
  539. CONFIG_CMD_SCSI * SCSI Support
  540. CONFIG_CMD_SDRAM * print SDRAM configuration information
  541. (requires CONFIG_CMD_I2C)
  542. CONFIG_CMD_SETGETDCR Support for DCR Register access
  543. (4xx only)
  544. CONFIG_CMD_SHA1 print sha1 memory digest
  545. (requires CONFIG_CMD_MEMORY)
  546. CONFIG_CMD_SOURCE "source" command Support
  547. CONFIG_CMD_SPI * SPI serial bus support
  548. CONFIG_CMD_USB * USB support
  549. CONFIG_CMD_VFD * VFD support (TRAB)
  550. CONFIG_CMD_CDP * Cisco Discover Protocol support
  551. CONFIG_CMD_FSL * Microblaze FSL support
  552. EXAMPLE: If you want all functions except of network
  553. support you can write:
  554. #include "config_cmd_all.h"
  555. #undef CONFIG_CMD_NET
  556. Other Commands:
  557. fdt (flattened device tree) command: CONFIG_OF_LIBFDT
  558. Note: Don't enable the "icache" and "dcache" commands
  559. (configuration option CONFIG_CMD_CACHE) unless you know
  560. what you (and your U-Boot users) are doing. Data
  561. cache cannot be enabled on systems like the 8xx or
  562. 8260 (where accesses to the IMMR region must be
  563. uncached), and it cannot be disabled on all other
  564. systems where we (mis-) use the data cache to hold an
  565. initial stack and some data.
  566. XXX - this list needs to get updated!
  567. - Watchdog:
  568. CONFIG_WATCHDOG
  569. If this variable is defined, it enables watchdog
  570. support. There must be support in the platform specific
  571. code for a watchdog. For the 8xx and 8260 CPUs, the
  572. SIU Watchdog feature is enabled in the SYPCR
  573. register.
  574. - U-Boot Version:
  575. CONFIG_VERSION_VARIABLE
  576. If this variable is defined, an environment variable
  577. named "ver" is created by U-Boot showing the U-Boot
  578. version as printed by the "version" command.
  579. This variable is readonly.
  580. - Real-Time Clock:
  581. When CONFIG_CMD_DATE is selected, the type of the RTC
  582. has to be selected, too. Define exactly one of the
  583. following options:
  584. CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
  585. CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
  586. CONFIG_RTC_MC13783 - use MC13783 RTC
  587. CONFIG_RTC_MC146818 - use MC146818 RTC
  588. CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
  589. CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
  590. CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
  591. CONFIG_RTC_DS164x - use Dallas DS164x RTC
  592. CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
  593. CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
  594. CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
  595. Note that if the RTC uses I2C, then the I2C interface
  596. must also be configured. See I2C Support, below.
  597. - GPIO Support:
  598. CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
  599. CONFIG_PCA953X_INFO - enable pca953x info command
  600. Note that if the GPIO device uses I2C, then the I2C interface
  601. must also be configured. See I2C Support, below.
  602. - Timestamp Support:
  603. When CONFIG_TIMESTAMP is selected, the timestamp
  604. (date and time) of an image is printed by image
  605. commands like bootm or iminfo. This option is
  606. automatically enabled when you select CONFIG_CMD_DATE .
  607. - Partition Support:
  608. CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
  609. and/or CONFIG_ISO_PARTITION and/or CONFIG_EFI_PARTITION
  610. If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
  611. CONFIG_CMD_SCSI) you must configure support for at
  612. least one partition type as well.
  613. - IDE Reset method:
  614. CONFIG_IDE_RESET_ROUTINE - this is defined in several
  615. board configurations files but used nowhere!
  616. CONFIG_IDE_RESET - is this is defined, IDE Reset will
  617. be performed by calling the function
  618. ide_set_reset(int reset)
  619. which has to be defined in a board specific file
  620. - ATAPI Support:
  621. CONFIG_ATAPI
  622. Set this to enable ATAPI support.
  623. - LBA48 Support
  624. CONFIG_LBA48
  625. Set this to enable support for disks larger than 137GB
  626. Also look at CONFIG_SYS_64BIT_LBA.
  627. Whithout these , LBA48 support uses 32bit variables and will 'only'
  628. support disks up to 2.1TB.
  629. CONFIG_SYS_64BIT_LBA:
  630. When enabled, makes the IDE subsystem use 64bit sector addresses.
  631. Default is 32bit.
  632. - SCSI Support:
  633. At the moment only there is only support for the
  634. SYM53C8XX SCSI controller; define
  635. CONFIG_SCSI_SYM53C8XX to enable it.
  636. CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
  637. CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
  638. CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
  639. maximum numbers of LUNs, SCSI ID's and target
  640. devices.
  641. CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
  642. - NETWORK Support (PCI):
  643. CONFIG_E1000
  644. Support for Intel 8254x gigabit chips.
  645. CONFIG_E1000_FALLBACK_MAC
  646. default MAC for empty EEPROM after production.
  647. CONFIG_EEPRO100
  648. Support for Intel 82557/82559/82559ER chips.
  649. Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
  650. write routine for first time initialisation.
  651. CONFIG_TULIP
  652. Support for Digital 2114x chips.
  653. Optional CONFIG_TULIP_SELECT_MEDIA for board specific
  654. modem chip initialisation (KS8761/QS6611).
  655. CONFIG_NATSEMI
  656. Support for National dp83815 chips.
  657. CONFIG_NS8382X
  658. Support for National dp8382[01] gigabit chips.
  659. - NETWORK Support (other):
  660. CONFIG_DRIVER_LAN91C96
  661. Support for SMSC's LAN91C96 chips.
  662. CONFIG_LAN91C96_BASE
  663. Define this to hold the physical address
  664. of the LAN91C96's I/O space
  665. CONFIG_LAN91C96_USE_32_BIT
  666. Define this to enable 32 bit addressing
  667. CONFIG_DRIVER_SMC91111
  668. Support for SMSC's LAN91C111 chip
  669. CONFIG_SMC91111_BASE
  670. Define this to hold the physical address
  671. of the device (I/O space)
  672. CONFIG_SMC_USE_32_BIT
  673. Define this if data bus is 32 bits
  674. CONFIG_SMC_USE_IOFUNCS
  675. Define this to use i/o functions instead of macros
  676. (some hardware wont work with macros)
  677. CONFIG_SMC911X
  678. Support for SMSC's LAN911x and LAN921x chips
  679. CONFIG_SMC911X_BASE
  680. Define this to hold the physical address
  681. of the device (I/O space)
  682. CONFIG_SMC911X_32_BIT
  683. Define this if data bus is 32 bits
  684. CONFIG_SMC911X_16_BIT
  685. Define this if data bus is 16 bits. If your processor
  686. automatically converts one 32 bit word to two 16 bit
  687. words you may also try CONFIG_SMC911X_32_BIT.
  688. - USB Support:
  689. At the moment only the UHCI host controller is
  690. supported (PIP405, MIP405, MPC5200); define
  691. CONFIG_USB_UHCI to enable it.
  692. define CONFIG_USB_KEYBOARD to enable the USB Keyboard
  693. and define CONFIG_USB_STORAGE to enable the USB
  694. storage devices.
  695. Note:
  696. Supported are USB Keyboards and USB Floppy drives
  697. (TEAC FD-05PUB).
  698. MPC5200 USB requires additional defines:
  699. CONFIG_USB_CLOCK
  700. for 528 MHz Clock: 0x0001bbbb
  701. CONFIG_PSC3_USB
  702. for USB on PSC3
  703. CONFIG_USB_CONFIG
  704. for differential drivers: 0x00001000
  705. for single ended drivers: 0x00005000
  706. for differential drivers on PSC3: 0x00000100
  707. for single ended drivers on PSC3: 0x00004100
  708. CONFIG_SYS_USB_EVENT_POLL
  709. May be defined to allow interrupt polling
  710. instead of using asynchronous interrupts
  711. - USB Device:
  712. Define the below if you wish to use the USB console.
  713. Once firmware is rebuilt from a serial console issue the
  714. command "setenv stdin usbtty; setenv stdout usbtty" and
  715. attach your USB cable. The Unix command "dmesg" should print
  716. it has found a new device. The environment variable usbtty
  717. can be set to gserial or cdc_acm to enable your device to
  718. appear to a USB host as a Linux gserial device or a
  719. Common Device Class Abstract Control Model serial device.
  720. If you select usbtty = gserial you should be able to enumerate
  721. a Linux host by
  722. # modprobe usbserial vendor=0xVendorID product=0xProductID
  723. else if using cdc_acm, simply setting the environment
  724. variable usbtty to be cdc_acm should suffice. The following
  725. might be defined in YourBoardName.h
  726. CONFIG_USB_DEVICE
  727. Define this to build a UDC device
  728. CONFIG_USB_TTY
  729. Define this to have a tty type of device available to
  730. talk to the UDC device
  731. CONFIG_SYS_CONSOLE_IS_IN_ENV
  732. Define this if you want stdin, stdout &/or stderr to
  733. be set to usbtty.
  734. mpc8xx:
  735. CONFIG_SYS_USB_EXTC_CLK 0xBLAH
  736. Derive USB clock from external clock "blah"
  737. - CONFIG_SYS_USB_EXTC_CLK 0x02
  738. CONFIG_SYS_USB_BRG_CLK 0xBLAH
  739. Derive USB clock from brgclk
  740. - CONFIG_SYS_USB_BRG_CLK 0x04
  741. If you have a USB-IF assigned VendorID then you may wish to
  742. define your own vendor specific values either in BoardName.h
  743. or directly in usbd_vendor_info.h. If you don't define
  744. CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
  745. CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
  746. should pretend to be a Linux device to it's target host.
  747. CONFIG_USBD_MANUFACTURER
  748. Define this string as the name of your company for
  749. - CONFIG_USBD_MANUFACTURER "my company"
  750. CONFIG_USBD_PRODUCT_NAME
  751. Define this string as the name of your product
  752. - CONFIG_USBD_PRODUCT_NAME "acme usb device"
  753. CONFIG_USBD_VENDORID
  754. Define this as your assigned Vendor ID from the USB
  755. Implementors Forum. This *must* be a genuine Vendor ID
  756. to avoid polluting the USB namespace.
  757. - CONFIG_USBD_VENDORID 0xFFFF
  758. CONFIG_USBD_PRODUCTID
  759. Define this as the unique Product ID
  760. for your device
  761. - CONFIG_USBD_PRODUCTID 0xFFFF
  762. - MMC Support:
  763. The MMC controller on the Intel PXA is supported. To
  764. enable this define CONFIG_MMC. The MMC can be
  765. accessed from the boot prompt by mapping the device
  766. to physical memory similar to flash. Command line is
  767. enabled with CONFIG_CMD_MMC. The MMC driver also works with
  768. the FAT fs. This is enabled with CONFIG_CMD_FAT.
  769. - Journaling Flash filesystem support:
  770. CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
  771. CONFIG_JFFS2_NAND_DEV
  772. Define these for a default partition on a NAND device
  773. CONFIG_SYS_JFFS2_FIRST_SECTOR,
  774. CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
  775. Define these for a default partition on a NOR device
  776. CONFIG_SYS_JFFS_CUSTOM_PART
  777. Define this to create an own partition. You have to provide a
  778. function struct part_info* jffs2_part_info(int part_num)
  779. If you define only one JFFS2 partition you may also want to
  780. #define CONFIG_SYS_JFFS_SINGLE_PART 1
  781. to disable the command chpart. This is the default when you
  782. have not defined a custom partition
  783. - Keyboard Support:
  784. CONFIG_ISA_KEYBOARD
  785. Define this to enable standard (PC-Style) keyboard
  786. support
  787. CONFIG_I8042_KBD
  788. Standard PC keyboard driver with US (is default) and
  789. GERMAN key layout (switch via environment 'keymap=de') support.
  790. Export function i8042_kbd_init, i8042_tstc and i8042_getc
  791. for cfb_console. Supports cursor blinking.
  792. - Video support:
  793. CONFIG_VIDEO
  794. Define this to enable video support (for output to
  795. video).
  796. CONFIG_VIDEO_CT69000
  797. Enable Chips & Technologies 69000 Video chip
  798. CONFIG_VIDEO_SMI_LYNXEM
  799. Enable Silicon Motion SMI 712/710/810 Video chip. The
  800. video output is selected via environment 'videoout'
  801. (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
  802. assumed.
  803. For the CT69000 and SMI_LYNXEM drivers, videomode is
  804. selected via environment 'videomode'. Two different ways
  805. are possible:
  806. - "videomode=num" 'num' is a standard LiLo mode numbers.
  807. Following standard modes are supported (* is default):
  808. Colors 640x480 800x600 1024x768 1152x864 1280x1024
  809. -------------+---------------------------------------------
  810. 8 bits | 0x301* 0x303 0x305 0x161 0x307
  811. 15 bits | 0x310 0x313 0x316 0x162 0x319
  812. 16 bits | 0x311 0x314 0x317 0x163 0x31A
  813. 24 bits | 0x312 0x315 0x318 ? 0x31B
  814. -------------+---------------------------------------------
  815. (i.e. setenv videomode 317; saveenv; reset;)
  816. - "videomode=bootargs" all the video parameters are parsed
  817. from the bootargs. (See drivers/video/videomodes.c)
  818. CONFIG_VIDEO_SED13806
  819. Enable Epson SED13806 driver. This driver supports 8bpp
  820. and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
  821. or CONFIG_VIDEO_SED13806_16BPP
  822. - Keyboard Support:
  823. CONFIG_KEYBOARD
  824. Define this to enable a custom keyboard support.
  825. This simply calls drv_keyboard_init() which must be
  826. defined in your board-specific files.
  827. The only board using this so far is RBC823.
  828. - LCD Support: CONFIG_LCD
  829. Define this to enable LCD support (for output to LCD
  830. display); also select one of the supported displays
  831. by defining one of these:
  832. CONFIG_ATMEL_LCD:
  833. HITACHI TX09D70VM1CCA, 3.5", 240x320.
  834. CONFIG_NEC_NL6448AC33:
  835. NEC NL6448AC33-18. Active, color, single scan.
  836. CONFIG_NEC_NL6448BC20
  837. NEC NL6448BC20-08. 6.5", 640x480.
  838. Active, color, single scan.
  839. CONFIG_NEC_NL6448BC33_54
  840. NEC NL6448BC33-54. 10.4", 640x480.
  841. Active, color, single scan.
  842. CONFIG_SHARP_16x9
  843. Sharp 320x240. Active, color, single scan.
  844. It isn't 16x9, and I am not sure what it is.
  845. CONFIG_SHARP_LQ64D341
  846. Sharp LQ64D341 display, 640x480.
  847. Active, color, single scan.
  848. CONFIG_HLD1045
  849. HLD1045 display, 640x480.
  850. Active, color, single scan.
  851. CONFIG_OPTREX_BW
  852. Optrex CBL50840-2 NF-FW 99 22 M5
  853. or
  854. Hitachi LMG6912RPFC-00T
  855. or
  856. Hitachi SP14Q002
  857. 320x240. Black & white.
  858. Normally display is black on white background; define
  859. CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
  860. - Splash Screen Support: CONFIG_SPLASH_SCREEN
  861. If this option is set, the environment is checked for
  862. a variable "splashimage". If found, the usual display
  863. of logo, copyright and system information on the LCD
  864. is suppressed and the BMP image at the address
  865. specified in "splashimage" is loaded instead. The
  866. console is redirected to the "nulldev", too. This
  867. allows for a "silent" boot where a splash screen is
  868. loaded very quickly after power-on.
  869. CONFIG_SPLASH_SCREEN_ALIGN
  870. If this option is set the splash image can be freely positioned
  871. on the screen. Environment variable "splashpos" specifies the
  872. position as "x,y". If a positive number is given it is used as
  873. number of pixel from left/top. If a negative number is given it
  874. is used as number of pixel from right/bottom. You can also
  875. specify 'm' for centering the image.
  876. Example:
  877. setenv splashpos m,m
  878. => image at center of screen
  879. setenv splashpos 30,20
  880. => image at x = 30 and y = 20
  881. setenv splashpos -10,m
  882. => vertically centered image
  883. at x = dspWidth - bmpWidth - 9
  884. - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
  885. If this option is set, additionally to standard BMP
  886. images, gzipped BMP images can be displayed via the
  887. splashscreen support or the bmp command.
  888. - Compression support:
  889. CONFIG_BZIP2
  890. If this option is set, support for bzip2 compressed
  891. images is included. If not, only uncompressed and gzip
  892. compressed images are supported.
  893. NOTE: the bzip2 algorithm requires a lot of RAM, so
  894. the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
  895. be at least 4MB.
  896. CONFIG_LZMA
  897. If this option is set, support for lzma compressed
  898. images is included.
  899. Note: The LZMA algorithm adds between 2 and 4KB of code and it
  900. requires an amount of dynamic memory that is given by the
  901. formula:
  902. (1846 + 768 << (lc + lp)) * sizeof(uint16)
  903. Where lc and lp stand for, respectively, Literal context bits
  904. and Literal pos bits.
  905. This value is upper-bounded by 14MB in the worst case. Anyway,
  906. for a ~4MB large kernel image, we have lc=3 and lp=0 for a
  907. total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
  908. a very small buffer.
  909. Use the lzmainfo tool to determinate the lc and lp values and
  910. then calculate the amount of needed dynamic memory (ensuring
  911. the appropriate CONFIG_SYS_MALLOC_LEN value).
  912. - MII/PHY support:
  913. CONFIG_PHY_ADDR
  914. The address of PHY on MII bus.
  915. CONFIG_PHY_CLOCK_FREQ (ppc4xx)
  916. The clock frequency of the MII bus
  917. CONFIG_PHY_GIGE
  918. If this option is set, support for speed/duplex
  919. detection of gigabit PHY is included.
  920. CONFIG_PHY_RESET_DELAY
  921. Some PHY like Intel LXT971A need extra delay after
  922. reset before any MII register access is possible.
  923. For such PHY, set this option to the usec delay
  924. required. (minimum 300usec for LXT971A)
  925. CONFIG_PHY_CMD_DELAY (ppc4xx)
  926. Some PHY like Intel LXT971A need extra delay after
  927. command issued before MII status register can be read
  928. - Ethernet address:
  929. CONFIG_ETHADDR
  930. CONFIG_ETH1ADDR
  931. CONFIG_ETH2ADDR
  932. CONFIG_ETH3ADDR
  933. CONFIG_ETH4ADDR
  934. CONFIG_ETH5ADDR
  935. Define a default value for Ethernet address to use
  936. for the respective Ethernet interface, in case this
  937. is not determined automatically.
  938. - IP address:
  939. CONFIG_IPADDR
  940. Define a default value for the IP address to use for
  941. the default Ethernet interface, in case this is not
  942. determined through e.g. bootp.
  943. - Server IP address:
  944. CONFIG_SERVERIP
  945. Defines a default value for the IP address of a TFTP
  946. server to contact when using the "tftboot" command.
  947. CONFIG_KEEP_SERVERADDR
  948. Keeps the server's MAC address, in the env 'serveraddr'
  949. for passing to bootargs (like Linux's netconsole option)
  950. - Multicast TFTP Mode:
  951. CONFIG_MCAST_TFTP
  952. Defines whether you want to support multicast TFTP as per
  953. rfc-2090; for example to work with atftp. Lets lots of targets
  954. tftp down the same boot image concurrently. Note: the Ethernet
  955. driver in use must provide a function: mcast() to join/leave a
  956. multicast group.
  957. CONFIG_BOOTP_RANDOM_DELAY
  958. - BOOTP Recovery Mode:
  959. CONFIG_BOOTP_RANDOM_DELAY
  960. If you have many targets in a network that try to
  961. boot using BOOTP, you may want to avoid that all
  962. systems send out BOOTP requests at precisely the same
  963. moment (which would happen for instance at recovery
  964. from a power failure, when all systems will try to
  965. boot, thus flooding the BOOTP server. Defining
  966. CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
  967. inserted before sending out BOOTP requests. The
  968. following delays are inserted then:
  969. 1st BOOTP request: delay 0 ... 1 sec
  970. 2nd BOOTP request: delay 0 ... 2 sec
  971. 3rd BOOTP request: delay 0 ... 4 sec
  972. 4th and following
  973. BOOTP requests: delay 0 ... 8 sec
  974. - DHCP Advanced Options:
  975. You can fine tune the DHCP functionality by defining
  976. CONFIG_BOOTP_* symbols:
  977. CONFIG_BOOTP_SUBNETMASK
  978. CONFIG_BOOTP_GATEWAY
  979. CONFIG_BOOTP_HOSTNAME
  980. CONFIG_BOOTP_NISDOMAIN
  981. CONFIG_BOOTP_BOOTPATH
  982. CONFIG_BOOTP_BOOTFILESIZE
  983. CONFIG_BOOTP_DNS
  984. CONFIG_BOOTP_DNS2
  985. CONFIG_BOOTP_SEND_HOSTNAME
  986. CONFIG_BOOTP_NTPSERVER
  987. CONFIG_BOOTP_TIMEOFFSET
  988. CONFIG_BOOTP_VENDOREX
  989. CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
  990. environment variable, not the BOOTP server.
  991. CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
  992. serverip from a DHCP server, it is possible that more
  993. than one DNS serverip is offered to the client.
  994. If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
  995. serverip will be stored in the additional environment
  996. variable "dnsip2". The first DNS serverip is always
  997. stored in the variable "dnsip", when CONFIG_BOOTP_DNS
  998. is defined.
  999. CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
  1000. to do a dynamic update of a DNS server. To do this, they
  1001. need the hostname of the DHCP requester.
  1002. If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
  1003. of the "hostname" environment variable is passed as
  1004. option 12 to the DHCP server.
  1005. CONFIG_BOOTP_DHCP_REQUEST_DELAY
  1006. A 32bit value in microseconds for a delay between
  1007. receiving a "DHCP Offer" and sending the "DHCP Request".
  1008. This fixes a problem with certain DHCP servers that don't
  1009. respond 100% of the time to a "DHCP request". E.g. On an
  1010. AT91RM9200 processor running at 180MHz, this delay needed
  1011. to be *at least* 15,000 usec before a Windows Server 2003
  1012. DHCP server would reply 100% of the time. I recommend at
  1013. least 50,000 usec to be safe. The alternative is to hope
  1014. that one of the retries will be successful but note that
  1015. the DHCP timeout and retry process takes a longer than
  1016. this delay.
  1017. - CDP Options:
  1018. CONFIG_CDP_DEVICE_ID
  1019. The device id used in CDP trigger frames.
  1020. CONFIG_CDP_DEVICE_ID_PREFIX
  1021. A two character string which is prefixed to the MAC address
  1022. of the device.
  1023. CONFIG_CDP_PORT_ID
  1024. A printf format string which contains the ascii name of
  1025. the port. Normally is set to "eth%d" which sets
  1026. eth0 for the first Ethernet, eth1 for the second etc.
  1027. CONFIG_CDP_CAPABILITIES
  1028. A 32bit integer which indicates the device capabilities;
  1029. 0x00000010 for a normal host which does not forwards.
  1030. CONFIG_CDP_VERSION
  1031. An ascii string containing the version of the software.
  1032. CONFIG_CDP_PLATFORM
  1033. An ascii string containing the name of the platform.
  1034. CONFIG_CDP_TRIGGER
  1035. A 32bit integer sent on the trigger.
  1036. CONFIG_CDP_POWER_CONSUMPTION
  1037. A 16bit integer containing the power consumption of the
  1038. device in .1 of milliwatts.
  1039. CONFIG_CDP_APPLIANCE_VLAN_TYPE
  1040. A byte containing the id of the VLAN.
  1041. - Status LED: CONFIG_STATUS_LED
  1042. Several configurations allow to display the current
  1043. status using a LED. For instance, the LED will blink
  1044. fast while running U-Boot code, stop blinking as
  1045. soon as a reply to a BOOTP request was received, and
  1046. start blinking slow once the Linux kernel is running
  1047. (supported by a status LED driver in the Linux
  1048. kernel). Defining CONFIG_STATUS_LED enables this
  1049. feature in U-Boot.
  1050. - CAN Support: CONFIG_CAN_DRIVER
  1051. Defining CONFIG_CAN_DRIVER enables CAN driver support
  1052. on those systems that support this (optional)
  1053. feature, like the TQM8xxL modules.
  1054. - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
  1055. These enable I2C serial bus commands. Defining either of
  1056. (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
  1057. include the appropriate I2C driver for the selected CPU.
  1058. This will allow you to use i2c commands at the u-boot
  1059. command line (as long as you set CONFIG_CMD_I2C in
  1060. CONFIG_COMMANDS) and communicate with i2c based realtime
  1061. clock chips. See common/cmd_i2c.c for a description of the
  1062. command line interface.
  1063. CONFIG_HARD_I2C selects a hardware I2C controller.
  1064. CONFIG_SOFT_I2C configures u-boot to use a software (aka
  1065. bit-banging) driver instead of CPM or similar hardware
  1066. support for I2C.
  1067. There are several other quantities that must also be
  1068. defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
  1069. In both cases you will need to define CONFIG_SYS_I2C_SPEED
  1070. to be the frequency (in Hz) at which you wish your i2c bus
  1071. to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
  1072. the CPU's i2c node address).
  1073. Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c)
  1074. sets the CPU up as a master node and so its address should
  1075. therefore be cleared to 0 (See, eg, MPC823e User's Manual
  1076. p.16-473). So, set CONFIG_SYS_I2C_SLAVE to 0.
  1077. CONFIG_SYS_I2C_INIT_MPC5XXX
  1078. When a board is reset during an i2c bus transfer
  1079. chips might think that the current transfer is still
  1080. in progress. Reset the slave devices by sending start
  1081. commands until the slave device responds.
  1082. That's all that's required for CONFIG_HARD_I2C.
  1083. If you use the software i2c interface (CONFIG_SOFT_I2C)
  1084. then the following macros need to be defined (examples are
  1085. from include/configs/lwmon.h):
  1086. I2C_INIT
  1087. (Optional). Any commands necessary to enable the I2C
  1088. controller or configure ports.
  1089. eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
  1090. I2C_PORT
  1091. (Only for MPC8260 CPU). The I/O port to use (the code
  1092. assumes both bits are on the same port). Valid values
  1093. are 0..3 for ports A..D.
  1094. I2C_ACTIVE
  1095. The code necessary to make the I2C data line active
  1096. (driven). If the data line is open collector, this
  1097. define can be null.
  1098. eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
  1099. I2C_TRISTATE
  1100. The code necessary to make the I2C data line tri-stated
  1101. (inactive). If the data line is open collector, this
  1102. define can be null.
  1103. eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
  1104. I2C_READ
  1105. Code that returns TRUE if the I2C data line is high,
  1106. FALSE if it is low.
  1107. eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
  1108. I2C_SDA(bit)
  1109. If <bit> is TRUE, sets the I2C data line high. If it
  1110. is FALSE, it clears it (low).
  1111. eg: #define I2C_SDA(bit) \
  1112. if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
  1113. else immr->im_cpm.cp_pbdat &= ~PB_SDA
  1114. I2C_SCL(bit)
  1115. If <bit> is TRUE, sets the I2C clock line high. If it
  1116. is FALSE, it clears it (low).
  1117. eg: #define I2C_SCL(bit) \
  1118. if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
  1119. else immr->im_cpm.cp_pbdat &= ~PB_SCL
  1120. I2C_DELAY
  1121. This delay is invoked four times per clock cycle so this
  1122. controls the rate of data transfer. The data rate thus
  1123. is 1 / (I2C_DELAY * 4). Often defined to be something
  1124. like:
  1125. #define I2C_DELAY udelay(2)
  1126. CONFIG_SYS_I2C_INIT_BOARD
  1127. When a board is reset during an i2c bus transfer
  1128. chips might think that the current transfer is still
  1129. in progress. On some boards it is possible to access
  1130. the i2c SCLK line directly, either by using the
  1131. processor pin as a GPIO or by having a second pin
  1132. connected to the bus. If this option is defined a
  1133. custom i2c_init_board() routine in boards/xxx/board.c
  1134. is run early in the boot sequence.
  1135. CONFIG_I2CFAST (PPC405GP|PPC405EP only)
  1136. This option enables configuration of bi_iic_fast[] flags
  1137. in u-boot bd_info structure based on u-boot environment
  1138. variable "i2cfast". (see also i2cfast)
  1139. CONFIG_I2C_MULTI_BUS
  1140. This option allows the use of multiple I2C buses, each of which
  1141. must have a controller. At any point in time, only one bus is
  1142. active. To switch to a different bus, use the 'i2c dev' command.
  1143. Note that bus numbering is zero-based.
  1144. CONFIG_SYS_I2C_NOPROBES
  1145. This option specifies a list of I2C devices that will be skipped
  1146. when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
  1147. is set, specify a list of bus-device pairs. Otherwise, specify
  1148. a 1D array of device addresses
  1149. e.g.
  1150. #undef CONFIG_I2C_MULTI_BUS
  1151. #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
  1152. will skip addresses 0x50 and 0x68 on a board with one I2C bus
  1153. #define CONFIG_I2C_MULTI_BUS
  1154. #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
  1155. will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
  1156. CONFIG_SYS_SPD_BUS_NUM
  1157. If defined, then this indicates the I2C bus number for DDR SPD.
  1158. If not defined, then U-Boot assumes that SPD is on I2C bus 0.
  1159. CONFIG_SYS_RTC_BUS_NUM
  1160. If defined, then this indicates the I2C bus number for the RTC.
  1161. If not defined, then U-Boot assumes that RTC is on I2C bus 0.
  1162. CONFIG_SYS_DTT_BUS_NUM
  1163. If defined, then this indicates the I2C bus number for the DTT.
  1164. If not defined, then U-Boot assumes that DTT is on I2C bus 0.
  1165. CONFIG_SYS_I2C_DTT_ADDR:
  1166. If defined, specifies the I2C address of the DTT device.
  1167. If not defined, then U-Boot uses predefined value for
  1168. specified DTT device.
  1169. CONFIG_FSL_I2C
  1170. Define this option if you want to use Freescale's I2C driver in
  1171. drivers/i2c/fsl_i2c.c.
  1172. CONFIG_I2C_MUX
  1173. Define this option if you have I2C devices reached over 1 .. n
  1174. I2C Muxes like the pca9544a. This option addes a new I2C
  1175. Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a
  1176. new I2C Bus to the existing I2C Busses. If you select the
  1177. new Bus with "i2c dev", u-bbot sends first the commandos for
  1178. the muxes to activate this new "bus".
  1179. CONFIG_I2C_MULTI_BUS must be also defined, to use this
  1180. feature!
  1181. Example:
  1182. Adding a new I2C Bus reached over 2 pca9544a muxes
  1183. The First mux with address 70 and channel 6
  1184. The Second mux with address 71 and channel 4
  1185. => i2c bus pca9544a:70:6:pca9544a:71:4
  1186. Use the "i2c bus" command without parameter, to get a list
  1187. of I2C Busses with muxes:
  1188. => i2c bus
  1189. Busses reached over muxes:
  1190. Bus ID: 2
  1191. reached over Mux(es):
  1192. pca9544a@70 ch: 4
  1193. Bus ID: 3
  1194. reached over Mux(es):
  1195. pca9544a@70 ch: 6
  1196. pca9544a@71 ch: 4
  1197. =>
  1198. If you now switch to the new I2C Bus 3 with "i2c dev 3"
  1199. u-boot sends First the Commando to the mux@70 to enable
  1200. channel 6, and then the Commando to the mux@71 to enable
  1201. the channel 4.
  1202. After that, you can use the "normal" i2c commands as
  1203. usual, to communicate with your I2C devices behind
  1204. the 2 muxes.
  1205. This option is actually implemented for the bitbanging
  1206. algorithm in common/soft_i2c.c and for the Hardware I2C
  1207. Bus on the MPC8260. But it should be not so difficult
  1208. to add this option to other architectures.
  1209. CONFIG_SOFT_I2C_READ_REPEATED_START
  1210. defining this will force the i2c_read() function in
  1211. the soft_i2c driver to perform an I2C repeated start
  1212. between writing the address pointer and reading the
  1213. data. If this define is omitted the default behaviour
  1214. of doing a stop-start sequence will be used. Most I2C
  1215. devices can use either method, but some require one or
  1216. the other.
  1217. - SPI Support: CONFIG_SPI
  1218. Enables SPI driver (so far only tested with
  1219. SPI EEPROM, also an instance works with Crystal A/D and
  1220. D/As on the SACSng board)
  1221. CONFIG_SPI_X
  1222. Enables extended (16-bit) SPI EEPROM addressing.
  1223. (symmetrical to CONFIG_I2C_X)
  1224. CONFIG_SOFT_SPI
  1225. Enables a software (bit-bang) SPI driver rather than
  1226. using hardware support. This is a general purpose
  1227. driver that only requires three general I/O port pins
  1228. (two outputs, one input) to function. If this is
  1229. defined, the board configuration must define several
  1230. SPI configuration items (port pins to use, etc). For
  1231. an example, see include/configs/sacsng.h.
  1232. CONFIG_HARD_SPI
  1233. Enables a hardware SPI driver for general-purpose reads
  1234. and writes. As with CONFIG_SOFT_SPI, the board configuration
  1235. must define a list of chip-select function pointers.
  1236. Currently supported on some MPC8xxx processors. For an
  1237. example, see include/configs/mpc8349emds.h.
  1238. CONFIG_MXC_SPI
  1239. Enables the driver for the SPI controllers on i.MX and MXC
  1240. SoCs. Currently only i.MX31 is supported.
  1241. - FPGA Support: CONFIG_FPGA
  1242. Enables FPGA subsystem.
  1243. CONFIG_FPGA_<vendor>
  1244. Enables support for specific chip vendors.
  1245. (ALTERA, XILINX)
  1246. CONFIG_FPGA_<family>
  1247. Enables support for FPGA family.
  1248. (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
  1249. CONFIG_FPGA_COUNT
  1250. Specify the number of FPGA devices to support.
  1251. CONFIG_SYS_FPGA_PROG_FEEDBACK
  1252. Enable printing of hash marks during FPGA configuration.
  1253. CONFIG_SYS_FPGA_CHECK_BUSY
  1254. Enable checks on FPGA configuration interface busy
  1255. status by the configuration function. This option
  1256. will require a board or device specific function to
  1257. be written.
  1258. CONFIG_FPGA_DELAY
  1259. If defined, a function that provides delays in the FPGA
  1260. configuration driver.
  1261. CONFIG_SYS_FPGA_CHECK_CTRLC
  1262. Allow Control-C to interrupt FPGA configuration
  1263. CONFIG_SYS_FPGA_CHECK_ERROR
  1264. Check for configuration errors during FPGA bitfile
  1265. loading. For example, abort during Virtex II
  1266. configuration if the INIT_B line goes low (which
  1267. indicated a CRC error).
  1268. CONFIG_SYS_FPGA_WAIT_INIT
  1269. Maximum time to wait for the INIT_B line to deassert
  1270. after PROB_B has been deasserted during a Virtex II
  1271. FPGA configuration sequence. The default time is 500
  1272. ms.
  1273. CONFIG_SYS_FPGA_WAIT_BUSY
  1274. Maximum time to wait for BUSY to deassert during
  1275. Virtex II FPGA configuration. The default is 5 ms.
  1276. CONFIG_SYS_FPGA_WAIT_CONFIG
  1277. Time to wait after FPGA configuration. The default is
  1278. 200 ms.
  1279. - Configuration Management:
  1280. CONFIG_IDENT_STRING
  1281. If defined, this string will be added to the U-Boot
  1282. version information (U_BOOT_VERSION)
  1283. - Vendor Parameter Protection:
  1284. U-Boot considers the values of the environment
  1285. variables "serial#" (Board Serial Number) and
  1286. "ethaddr" (Ethernet Address) to be parameters that
  1287. are set once by the board vendor / manufacturer, and
  1288. protects these variables from casual modification by
  1289. the user. Once set, these variables are read-only,
  1290. and write or delete attempts are rejected. You can
  1291. change this behaviour:
  1292. If CONFIG_ENV_OVERWRITE is #defined in your config
  1293. file, the write protection for vendor parameters is
  1294. completely disabled. Anybody can change or delete
  1295. these parameters.
  1296. Alternatively, if you #define _both_ CONFIG_ETHADDR
  1297. _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
  1298. Ethernet address is installed in the environment,
  1299. which can be changed exactly ONCE by the user. [The
  1300. serial# is unaffected by this, i. e. it remains
  1301. read-only.]
  1302. - Protected RAM:
  1303. CONFIG_PRAM
  1304. Define this variable to enable the reservation of
  1305. "protected RAM", i. e. RAM which is not overwritten
  1306. by U-Boot. Define CONFIG_PRAM to hold the number of
  1307. kB you want to reserve for pRAM. You can overwrite
  1308. this default value by defining an environment
  1309. variable "pram" to the number of kB you want to
  1310. reserve. Note that the board info structure will
  1311. still show the full amount of RAM. If pRAM is
  1312. reserved, a new environment variable "mem" will
  1313. automatically be defined to hold the amount of
  1314. remaining RAM in a form that can be passed as boot
  1315. argument to Linux, for instance like that:
  1316. setenv bootargs ... mem=\${mem}
  1317. saveenv
  1318. This way you can tell Linux not to use this memory,
  1319. either, which results in a memory region that will
  1320. not be affected by reboots.
  1321. *WARNING* If your board configuration uses automatic
  1322. detection of the RAM size, you must make sure that
  1323. this memory test is non-destructive. So far, the
  1324. following board configurations are known to be
  1325. "pRAM-clean":
  1326. ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
  1327. HERMES, IP860, RPXlite, LWMON, LANTEC,
  1328. PCU_E, FLAGADM, TQM8260
  1329. - Error Recovery:
  1330. CONFIG_PANIC_HANG
  1331. Define this variable to stop the system in case of a
  1332. fatal error, so that you have to reset it manually.
  1333. This is probably NOT a good idea for an embedded
  1334. system where you want the system to reboot
  1335. automatically as fast as possible, but it may be
  1336. useful during development since you can try to debug
  1337. the conditions that lead to the situation.
  1338. CONFIG_NET_RETRY_COUNT
  1339. This variable defines the number of retries for
  1340. network operations like ARP, RARP, TFTP, or BOOTP
  1341. before giving up the operation. If not defined, a
  1342. default value of 5 is used.
  1343. CONFIG_ARP_TIMEOUT
  1344. Timeout waiting for an ARP reply in milliseconds.
  1345. - Command Interpreter:
  1346. CONFIG_AUTO_COMPLETE
  1347. Enable auto completion of commands using TAB.
  1348. Note that this feature has NOT been implemented yet
  1349. for the "hush" shell.
  1350. CONFIG_SYS_HUSH_PARSER
  1351. Define this variable to enable the "hush" shell (from
  1352. Busybox) as command line interpreter, thus enabling
  1353. powerful command line syntax like
  1354. if...then...else...fi conditionals or `&&' and '||'
  1355. constructs ("shell scripts").
  1356. If undefined, you get the old, much simpler behaviour
  1357. with a somewhat smaller memory footprint.
  1358. CONFIG_SYS_PROMPT_HUSH_PS2
  1359. This defines the secondary prompt string, which is
  1360. printed when the command interpreter needs more input
  1361. to complete a command. Usually "> ".
  1362. Note:
  1363. In the current implementation, the local variables
  1364. space and global environment variables space are
  1365. separated. Local variables are those you define by
  1366. simply typing `name=value'. To access a local
  1367. variable later on, you have write `$name' or
  1368. `${name}'; to execute the contents of a variable
  1369. directly type `$name' at the command prompt.
  1370. Global environment variables are those you use
  1371. setenv/printenv to work with. To run a command stored
  1372. in such a variable, you need to use the run command,
  1373. and you must not use the '$' sign to access them.
  1374. To store commands and special characters in a
  1375. variable, please use double quotation marks
  1376. surrounding the whole text of the variable, instead
  1377. of the backslashes before semicolons and special
  1378. symbols.
  1379. - Commandline Editing and History:
  1380. CONFIG_CMDLINE_EDITING
  1381. Enable editing and History functions for interactive
  1382. commandline input operations
  1383. - Default Environment:
  1384. CONFIG_EXTRA_ENV_SETTINGS
  1385. Define this to contain any number of null terminated
  1386. strings (variable = value pairs) that will be part of
  1387. the default environment compiled into the boot image.
  1388. For example, place something like this in your
  1389. board's config file:
  1390. #define CONFIG_EXTRA_ENV_SETTINGS \
  1391. "myvar1=value1\0" \
  1392. "myvar2=value2\0"
  1393. Warning: This method is based on knowledge about the
  1394. internal format how the environment is stored by the
  1395. U-Boot code. This is NOT an official, exported
  1396. interface! Although it is unlikely that this format
  1397. will change soon, there is no guarantee either.
  1398. You better know what you are doing here.
  1399. Note: overly (ab)use of the default environment is
  1400. discouraged. Make sure to check other ways to preset
  1401. the environment like the "source" command or the
  1402. boot command first.
  1403. - DataFlash Support:
  1404. CONFIG_HAS_DATAFLASH
  1405. Defining this option enables DataFlash features and
  1406. allows to read/write in Dataflash via the standard
  1407. commands cp, md...
  1408. - SystemACE Support:
  1409. CONFIG_SYSTEMACE
  1410. Adding this option adds support for Xilinx SystemACE
  1411. chips attached via some sort of local bus. The address
  1412. of the chip must also be defined in the
  1413. CONFIG_SYS_SYSTEMACE_BASE macro. For example:
  1414. #define CONFIG_SYSTEMACE
  1415. #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
  1416. When SystemACE support is added, the "ace" device type
  1417. becomes available to the fat commands, i.e. fatls.
  1418. - TFTP Fixed UDP Port:
  1419. CONFIG_TFTP_PORT
  1420. If this is defined, the environment variable tftpsrcp
  1421. is used to supply the TFTP UDP source port value.
  1422. If tftpsrcp isn't defined, the normal pseudo-random port
  1423. number generator is used.
  1424. Also, the environment variable tftpdstp is used to supply
  1425. the TFTP UDP destination port value. If tftpdstp isn't
  1426. defined, the normal port 69 is used.
  1427. The purpose for tftpsrcp is to allow a TFTP server to
  1428. blindly start the TFTP transfer using the pre-configured
  1429. target IP address and UDP port. This has the effect of
  1430. "punching through" the (Windows XP) firewall, allowing
  1431. the remainder of the TFTP transfer to proceed normally.
  1432. A better solution is to properly configure the firewall,
  1433. but sometimes that is not allowed.
  1434. - Show boot progress:
  1435. CONFIG_SHOW_BOOT_PROGRESS
  1436. Defining this option allows to add some board-
  1437. specific code (calling a user-provided function
  1438. "show_boot_progress(int)") that enables you to show
  1439. the system's boot progress on some display (for
  1440. example, some LED's) on your board. At the moment,
  1441. the following checkpoints are implemented:
  1442. Legacy uImage format:
  1443. Arg Where When
  1444. 1 common/cmd_bootm.c before attempting to boot an image
  1445. -1 common/cmd_bootm.c Image header has bad magic number
  1446. 2 common/cmd_bootm.c Image header has correct magic number
  1447. -2 common/cmd_bootm.c Image header has bad checksum
  1448. 3 common/cmd_bootm.c Image header has correct checksum
  1449. -3 common/cmd_bootm.c Image data has bad checksum
  1450. 4 common/cmd_bootm.c Image data has correct checksum
  1451. -4 common/cmd_bootm.c Image is for unsupported architecture
  1452. 5 common/cmd_bootm.c Architecture check OK
  1453. -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
  1454. 6 common/cmd_bootm.c Image Type check OK
  1455. -6 common/cmd_bootm.c gunzip uncompression error
  1456. -7 common/cmd_bootm.c Unimplemented compression type
  1457. 7 common/cmd_bootm.c Uncompression OK
  1458. 8 common/cmd_bootm.c No uncompress/copy overwrite error
  1459. -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
  1460. 9 common/image.c Start initial ramdisk verification
  1461. -10 common/image.c Ramdisk header has bad magic number
  1462. -11 common/image.c Ramdisk header has bad checksum
  1463. 10 common/image.c Ramdisk header is OK
  1464. -12 common/image.c Ramdisk data has bad checksum
  1465. 11 common/image.c Ramdisk data has correct checksum
  1466. 12 common/image.c Ramdisk verification complete, start loading
  1467. -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
  1468. 13 common/image.c Start multifile image verification
  1469. 14 common/image.c No initial ramdisk, no multifile, continue.
  1470. 15 lib_<arch>/bootm.c All preparation done, transferring control to OS
  1471. -30 lib_ppc/board.c Fatal error, hang the system
  1472. -31 post/post.c POST test failed, detected by post_output_backlog()
  1473. -32 post/post.c POST test failed, detected by post_run_single()
  1474. 34 common/cmd_doc.c before loading a Image from a DOC device
  1475. -35 common/cmd_doc.c Bad usage of "doc" command
  1476. 35 common/cmd_doc.c correct usage of "doc" command
  1477. -36 common/cmd_doc.c No boot device
  1478. 36 common/cmd_doc.c correct boot device
  1479. -37 common/cmd_doc.c Unknown Chip ID on boot device
  1480. 37 common/cmd_doc.c correct chip ID found, device available
  1481. -38 common/cmd_doc.c Read Error on boot device
  1482. 38 common/cmd_doc.c reading Image header from DOC device OK
  1483. -39 common/cmd_doc.c Image header has bad magic number
  1484. 39 common/cmd_doc.c Image header has correct magic number
  1485. -40 common/cmd_doc.c Error reading Image from DOC device
  1486. 40 common/cmd_doc.c Image header has correct magic number
  1487. 41 common/cmd_ide.c before loading a Image from a IDE device
  1488. -42 common/cmd_ide.c Bad usage of "ide" command
  1489. 42 common/cmd_ide.c correct usage of "ide" command
  1490. -43 common/cmd_ide.c No boot device
  1491. 43 common/cmd_ide.c boot device found
  1492. -44 common/cmd_ide.c Device not available
  1493. 44 common/cmd_ide.c Device available
  1494. -45 common/cmd_ide.c wrong partition selected
  1495. 45 common/cmd_ide.c partition selected
  1496. -46 common/cmd_ide.c Unknown partition table
  1497. 46 common/cmd_ide.c valid partition table found
  1498. -47 common/cmd_ide.c Invalid partition type
  1499. 47 common/cmd_ide.c correct partition type
  1500. -48 common/cmd_ide.c Error reading Image Header on boot device
  1501. 48 common/cmd_ide.c reading Image Header from IDE device OK
  1502. -49 common/cmd_ide.c Image header has bad magic number
  1503. 49 common/cmd_ide.c Image header has correct magic number
  1504. -50 common/cmd_ide.c Image header has bad checksum
  1505. 50 common/cmd_ide.c Image header has correct checksum
  1506. -51 common/cmd_ide.c Error reading Image from IDE device
  1507. 51 common/cmd_ide.c reading Image from IDE device OK
  1508. 52 common/cmd_nand.c before loading a Image from a NAND device
  1509. -53 common/cmd_nand.c Bad usage of "nand" command
  1510. 53 common/cmd_nand.c correct usage of "nand" command
  1511. -54 common/cmd_nand.c No boot device
  1512. 54 common/cmd_nand.c boot device found
  1513. -55 common/cmd_nand.c Unknown Chip ID on boot device
  1514. 55 common/cmd_nand.c correct chip ID found, device available
  1515. -56 common/cmd_nand.c Error reading Image Header on boot device
  1516. 56 common/cmd_nand.c reading Image Header from NAND device OK
  1517. -57 common/cmd_nand.c Image header has bad magic number
  1518. 57 common/cmd_nand.c Image header has correct magic number
  1519. -58 common/cmd_nand.c Error reading Image from NAND device
  1520. 58 common/cmd_nand.c reading Image from NAND device OK
  1521. -60 common/env_common.c Environment has a bad CRC, using default
  1522. 64 net/eth.c starting with Ethernet configuration.
  1523. -64 net/eth.c no Ethernet found.
  1524. 65 net/eth.c Ethernet found.
  1525. -80 common/cmd_net.c usage wrong
  1526. 80 common/cmd_net.c before calling NetLoop()
  1527. -81 common/cmd_net.c some error in NetLoop() occurred
  1528. 81 common/cmd_net.c NetLoop() back without error
  1529. -82 common/cmd_net.c size == 0 (File with size 0 loaded)
  1530. 82 common/cmd_net.c trying automatic boot
  1531. 83 common/cmd_net.c running "source" command
  1532. -83 common/cmd_net.c some error in automatic boot or "source" command
  1533. 84 common/cmd_net.c end without errors
  1534. FIT uImage format:
  1535. Arg Where When
  1536. 100 common/cmd_bootm.c Kernel FIT Image has correct format
  1537. -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
  1538. 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
  1539. -101 common/cmd_bootm.c Can't get configuration for kernel subimage
  1540. 102 common/cmd_bootm.c Kernel unit name specified
  1541. -103 common/cmd_bootm.c Can't get kernel subimage node offset
  1542. 103 common/cmd_bootm.c Found configuration node
  1543. 104 common/cmd_bootm.c Got kernel subimage node offset
  1544. -104 common/cmd_bootm.c Kernel subimage hash verification failed
  1545. 105 common/cmd_bootm.c Kernel subimage hash verification OK
  1546. -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
  1547. 106 common/cmd_bootm.c Architecture check OK
  1548. -106 common/cmd_bootm.c Kernel subimage has wrong type
  1549. 107 common/cmd_bootm.c Kernel subimage type OK
  1550. -107 common/cmd_bootm.c Can't get kernel subimage data/size
  1551. 108 common/cmd_bootm.c Got kernel subimage data/size
  1552. -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
  1553. -109 common/cmd_bootm.c Can't get kernel subimage type
  1554. -110 common/cmd_bootm.c Can't get kernel subimage comp
  1555. -111 common/cmd_bootm.c Can't get kernel subimage os
  1556. -112 common/cmd_bootm.c Can't get kernel subimage load address
  1557. -113 common/cmd_bootm.c Image uncompress/copy overwrite error
  1558. 120 common/image.c Start initial ramdisk verification
  1559. -120 common/image.c Ramdisk FIT image has incorrect format
  1560. 121 common/image.c Ramdisk FIT image has correct format
  1561. 122 common/image.c No ramdisk subimage unit name, using configuration
  1562. -122 common/image.c Can't get configuration for ramdisk subimage
  1563. 123 common/image.c Ramdisk unit name specified
  1564. -124 common/image.c Can't get ramdisk subimage node offset
  1565. 125 common/image.c Got ramdisk subimage node offset
  1566. -125 common/image.c Ramdisk subimage hash verification failed
  1567. 126 common/image.c Ramdisk subimage hash verification OK
  1568. -126 common/image.c Ramdisk subimage for unsupported architecture
  1569. 127 common/image.c Architecture check OK
  1570. -127 common/image.c Can't get ramdisk subimage data/size
  1571. 128 common/image.c Got ramdisk subimage data/size
  1572. 129 common/image.c Can't get ramdisk load address
  1573. -129 common/image.c Got ramdisk load address
  1574. -130 common/cmd_doc.c Incorrect FIT image format
  1575. 131 common/cmd_doc.c FIT image format OK
  1576. -140 common/cmd_ide.c Incorrect FIT image format
  1577. 141 common/cmd_ide.c FIT image format OK
  1578. -150 common/cmd_nand.c Incorrect FIT image format
  1579. 151 common/cmd_nand.c FIT image format OK
  1580. - Automatic software updates via TFTP server
  1581. CONFIG_UPDATE_TFTP
  1582. CONFIG_UPDATE_TFTP_CNT_MAX
  1583. CONFIG_UPDATE_TFTP_MSEC_MAX
  1584. These options enable and control the auto-update feature;
  1585. for a more detailed description refer to doc/README.update.
  1586. - MTD Support (mtdparts command, UBI support)
  1587. CONFIG_MTD_DEVICE
  1588. Adds the MTD device infrastructure from the Linux kernel.
  1589. Needed for mtdparts command support.
  1590. CONFIG_MTD_PARTITIONS
  1591. Adds the MTD partitioning infrastructure from the Linux
  1592. kernel. Needed for UBI support.
  1593. Modem Support:
  1594. --------------
  1595. [so far only for SMDK2400 and TRAB boards]
  1596. - Modem support enable:
  1597. CONFIG_MODEM_SUPPORT
  1598. - RTS/CTS Flow control enable:
  1599. CONFIG_HWFLOW
  1600. - Modem debug support:
  1601. CONFIG_MODEM_SUPPORT_DEBUG
  1602. Enables debugging stuff (char screen[1024], dbg())
  1603. for modem support. Useful only with BDI2000.
  1604. - Interrupt support (PPC):
  1605. There are common interrupt_init() and timer_interrupt()
  1606. for all PPC archs. interrupt_init() calls interrupt_init_cpu()
  1607. for CPU specific initialization. interrupt_init_cpu()
  1608. should set decrementer_count to appropriate value. If
  1609. CPU resets decrementer automatically after interrupt
  1610. (ppc4xx) it should set decrementer_count to zero.
  1611. timer_interrupt() calls timer_interrupt_cpu() for CPU
  1612. specific handling. If board has watchdog / status_led
  1613. / other_activity_monitor it works automatically from
  1614. general timer_interrupt().
  1615. - General:
  1616. In the target system modem support is enabled when a
  1617. specific key (key combination) is pressed during
  1618. power-on. Otherwise U-Boot will boot normally
  1619. (autoboot). The key_pressed() function is called from
  1620. board_init(). Currently key_pressed() is a dummy
  1621. function, returning 1 and thus enabling modem
  1622. initialization.
  1623. If there are no modem init strings in the
  1624. environment, U-Boot proceed to autoboot; the
  1625. previous output (banner, info printfs) will be
  1626. suppressed, though.
  1627. See also: doc/README.Modem
  1628. Configuration Settings:
  1629. -----------------------
  1630. - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
  1631. undefine this when you're short of memory.
  1632. - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
  1633. width of the commands listed in the 'help' command output.
  1634. - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
  1635. prompt for user input.
  1636. - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
  1637. - CONFIG_SYS_PBSIZE: Buffer size for Console output
  1638. - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
  1639. - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
  1640. the application (usually a Linux kernel) when it is
  1641. booted
  1642. - CONFIG_SYS_BAUDRATE_TABLE:
  1643. List of legal baudrate settings for this board.
  1644. - CONFIG_SYS_CONSOLE_INFO_QUIET
  1645. Suppress display of console information at boot.
  1646. - CONFIG_SYS_CONSOLE_IS_IN_ENV
  1647. If the board specific function
  1648. extern int overwrite_console (void);
  1649. returns 1, the stdin, stderr and stdout are switched to the
  1650. serial port, else the settings in the environment are used.
  1651. - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
  1652. Enable the call to overwrite_console().
  1653. - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
  1654. Enable overwrite of previous console environment settings.
  1655. - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
  1656. Begin and End addresses of the area used by the
  1657. simple memory test.
  1658. - CONFIG_SYS_ALT_MEMTEST:
  1659. Enable an alternate, more extensive memory test.
  1660. - CONFIG_SYS_MEMTEST_SCRATCH:
  1661. Scratch address used by the alternate memory test
  1662. You only need to set this if address zero isn't writeable
  1663. - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
  1664. If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
  1665. this specified memory area will get subtracted from the top
  1666. (end) of RAM and won't get "touched" at all by U-Boot. By
  1667. fixing up gd->ram_size the Linux kernel should gets passed
  1668. the now "corrected" memory size and won't touch it either.
  1669. This should work for arch/ppc and arch/powerpc. Only Linux
  1670. board ports in arch/powerpc with bootwrapper support that
  1671. recalculate the memory size from the SDRAM controller setup
  1672. will have to get fixed in Linux additionally.
  1673. This option can be used as a workaround for the 440EPx/GRx
  1674. CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
  1675. be touched.
  1676. WARNING: Please make sure that this value is a multiple of
  1677. the Linux page size (normally 4k). If this is not the case,
  1678. then the end address of the Linux memory will be located at a
  1679. non page size aligned address and this could cause major
  1680. problems.
  1681. - CONFIG_SYS_TFTP_LOADADDR:
  1682. Default load address for network file downloads
  1683. - CONFIG_SYS_LOADS_BAUD_CHANGE:
  1684. Enable temporary baudrate change while serial download
  1685. - CONFIG_SYS_SDRAM_BASE:
  1686. Physical start address of SDRAM. _Must_ be 0 here.
  1687. - CONFIG_SYS_MBIO_BASE:
  1688. Physical start address of Motherboard I/O (if using a
  1689. Cogent motherboard)
  1690. - CONFIG_SYS_FLASH_BASE:
  1691. Physical start address of Flash memory.
  1692. - CONFIG_SYS_MONITOR_BASE:
  1693. Physical start address of boot monitor code (set by
  1694. make config files to be same as the text base address
  1695. (TEXT_BASE) used when linking) - same as
  1696. CONFIG_SYS_FLASH_BASE when booting from flash.
  1697. - CONFIG_SYS_MONITOR_LEN:
  1698. Size of memory reserved for monitor code, used to
  1699. determine _at_compile_time_ (!) if the environment is
  1700. embedded within the U-Boot image, or in a separate
  1701. flash sector.
  1702. - CONFIG_SYS_MALLOC_LEN:
  1703. Size of DRAM reserved for malloc() use.
  1704. - CONFIG_SYS_BOOTM_LEN:
  1705. Normally compressed uImages are limited to an
  1706. uncompressed size of 8 MBytes. If this is not enough,
  1707. you can define CONFIG_SYS_BOOTM_LEN in your board config file
  1708. to adjust this setting to your needs.
  1709. - CONFIG_SYS_BOOTMAPSZ:
  1710. Maximum size of memory mapped by the startup code of
  1711. the Linux kernel; all data that must be processed by
  1712. the Linux kernel (bd_info, boot arguments, FDT blob if
  1713. used) must be put below this limit, unless "bootm_low"
  1714. enviroment variable is defined and non-zero. In such case
  1715. all data for the Linux kernel must be between "bootm_low"
  1716. and "bootm_low" + CONFIG_SYS_BOOTMAPSZ.
  1717. - CONFIG_SYS_MAX_FLASH_BANKS:
  1718. Max number of Flash memory banks
  1719. - CONFIG_SYS_MAX_FLASH_SECT:
  1720. Max number of sectors on a Flash chip
  1721. - CONFIG_SYS_FLASH_ERASE_TOUT:
  1722. Timeout for Flash erase operations (in ms)
  1723. - CONFIG_SYS_FLASH_WRITE_TOUT:
  1724. Timeout for Flash write operations (in ms)
  1725. - CONFIG_SYS_FLASH_LOCK_TOUT
  1726. Timeout for Flash set sector lock bit operation (in ms)
  1727. - CONFIG_SYS_FLASH_UNLOCK_TOUT
  1728. Timeout for Flash clear lock bits operation (in ms)
  1729. - CONFIG_SYS_FLASH_PROTECTION
  1730. If defined, hardware flash sectors protection is used
  1731. instead of U-Boot software protection.
  1732. - CONFIG_SYS_DIRECT_FLASH_TFTP:
  1733. Enable TFTP transfers directly to flash memory;
  1734. without this option such a download has to be
  1735. performed in two steps: (1) download to RAM, and (2)
  1736. copy from RAM to flash.
  1737. The two-step approach is usually more reliable, since
  1738. you can check if the download worked before you erase
  1739. the flash, but in some situations (when system RAM is
  1740. too limited to allow for a temporary copy of the
  1741. downloaded image) this option may be very useful.
  1742. - CONFIG_SYS_FLASH_CFI:
  1743. Define if the flash driver uses extra elements in the
  1744. common flash structure for storing flash geometry.
  1745. - CONFIG_FLASH_CFI_DRIVER
  1746. This option also enables the building of the cfi_flash driver
  1747. in the drivers directory
  1748. - CONFIG_FLASH_CFI_MTD
  1749. This option enables the building of the cfi_mtd driver
  1750. in the drivers directory. The driver exports CFI flash
  1751. to the MTD layer.
  1752. - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
  1753. Use buffered writes to flash.
  1754. - CONFIG_FLASH_SPANSION_S29WS_N
  1755. s29ws-n MirrorBit flash has non-standard addresses for buffered
  1756. write commands.
  1757. - CONFIG_SYS_FLASH_QUIET_TEST
  1758. If this option is defined, the common CFI flash doesn't
  1759. print it's warning upon not recognized FLASH banks. This
  1760. is useful, if some of the configured banks are only
  1761. optionally available.
  1762. - CONFIG_FLASH_SHOW_PROGRESS
  1763. If defined (must be an integer), print out countdown
  1764. digits and dots. Recommended value: 45 (9..1) for 80
  1765. column displays, 15 (3..1) for 40 column displays.
  1766. - CONFIG_SYS_RX_ETH_BUFFER:
  1767. Defines the number of Ethernet receive buffers. On some
  1768. Ethernet controllers it is recommended to set this value
  1769. to 8 or even higher (EEPRO100 or 405 EMAC), since all
  1770. buffers can be full shortly after enabling the interface
  1771. on high Ethernet traffic.
  1772. Defaults to 4 if not defined.
  1773. The following definitions that deal with the placement and management
  1774. of environment data (variable area); in general, we support the
  1775. following configurations:
  1776. - CONFIG_ENV_IS_IN_FLASH:
  1777. Define this if the environment is in flash memory.
  1778. a) The environment occupies one whole flash sector, which is
  1779. "embedded" in the text segment with the U-Boot code. This
  1780. happens usually with "bottom boot sector" or "top boot
  1781. sector" type flash chips, which have several smaller
  1782. sectors at the start or the end. For instance, such a
  1783. layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
  1784. such a case you would place the environment in one of the
  1785. 4 kB sectors - with U-Boot code before and after it. With
  1786. "top boot sector" type flash chips, you would put the
  1787. environment in one of the last sectors, leaving a gap
  1788. between U-Boot and the environment.
  1789. - CONFIG_ENV_OFFSET:
  1790. Offset of environment data (variable area) to the
  1791. beginning of flash memory; for instance, with bottom boot
  1792. type flash chips the second sector can be used: the offset
  1793. for this sector is given here.
  1794. CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
  1795. - CONFIG_ENV_ADDR:
  1796. This is just another way to specify the start address of
  1797. the flash sector containing the environment (instead of
  1798. CONFIG_ENV_OFFSET).
  1799. - CONFIG_ENV_SECT_SIZE:
  1800. Size of the sector containing the environment.
  1801. b) Sometimes flash chips have few, equal sized, BIG sectors.
  1802. In such a case you don't want to spend a whole sector for
  1803. the environment.
  1804. - CONFIG_ENV_SIZE:
  1805. If you use this in combination with CONFIG_ENV_IS_IN_FLASH
  1806. and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
  1807. of this flash sector for the environment. This saves
  1808. memory for the RAM copy of the environment.
  1809. It may also save flash memory if you decide to use this
  1810. when your environment is "embedded" within U-Boot code,
  1811. since then the remainder of the flash sector could be used
  1812. for U-Boot code. It should be pointed out that this is
  1813. STRONGLY DISCOURAGED from a robustness point of view:
  1814. updating the environment in flash makes it always
  1815. necessary to erase the WHOLE sector. If something goes
  1816. wrong before the contents has been restored from a copy in
  1817. RAM, your target system will be dead.
  1818. - CONFIG_ENV_ADDR_REDUND
  1819. CONFIG_ENV_SIZE_REDUND
  1820. These settings describe a second storage area used to hold
  1821. a redundant copy of the environment data, so that there is
  1822. a valid backup copy in case there is a power failure during
  1823. a "saveenv" operation.
  1824. BE CAREFUL! Any changes to the flash layout, and some changes to the
  1825. source code will make it necessary to adapt <board>/u-boot.lds*
  1826. accordingly!
  1827. - CONFIG_ENV_IS_IN_NVRAM:
  1828. Define this if you have some non-volatile memory device
  1829. (NVRAM, battery buffered SRAM) which you want to use for the
  1830. environment.
  1831. - CONFIG_ENV_ADDR:
  1832. - CONFIG_ENV_SIZE:
  1833. These two #defines are used to determine the memory area you
  1834. want to use for environment. It is assumed that this memory
  1835. can just be read and written to, without any special
  1836. provision.
  1837. BE CAREFUL! The first access to the environment happens quite early
  1838. in U-Boot initalization (when we try to get the setting of for the
  1839. console baudrate). You *MUST* have mapped your NVRAM area then, or
  1840. U-Boot will hang.
  1841. Please note that even with NVRAM we still use a copy of the
  1842. environment in RAM: we could work on NVRAM directly, but we want to
  1843. keep settings there always unmodified except somebody uses "saveenv"
  1844. to save the current settings.
  1845. - CONFIG_ENV_IS_IN_EEPROM:
  1846. Use this if you have an EEPROM or similar serial access
  1847. device and a driver for it.
  1848. - CONFIG_ENV_OFFSET:
  1849. - CONFIG_ENV_SIZE:
  1850. These two #defines specify the offset and size of the
  1851. environment area within the total memory of your EEPROM.
  1852. - CONFIG_SYS_I2C_EEPROM_ADDR:
  1853. If defined, specified the chip address of the EEPROM device.
  1854. The default address is zero.
  1855. - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
  1856. If defined, the number of bits used to address bytes in a
  1857. single page in the EEPROM device. A 64 byte page, for example
  1858. would require six bits.
  1859. - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
  1860. If defined, the number of milliseconds to delay between
  1861. page writes. The default is zero milliseconds.
  1862. - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
  1863. The length in bytes of the EEPROM memory array address. Note
  1864. that this is NOT the chip address length!
  1865. - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
  1866. EEPROM chips that implement "address overflow" are ones
  1867. like Catalyst 24WC04/08/16 which has 9/10/11 bits of
  1868. address and the extra bits end up in the "chip address" bit
  1869. slots. This makes a 24WC08 (1Kbyte) chip look like four 256
  1870. byte chips.
  1871. Note that we consider the length of the address field to
  1872. still be one byte because the extra address bits are hidden
  1873. in the chip address.
  1874. - CONFIG_SYS_EEPROM_SIZE:
  1875. The size in bytes of the EEPROM device.
  1876. - CONFIG_ENV_IS_IN_DATAFLASH:
  1877. Define this if you have a DataFlash memory device which you
  1878. want to use for the environment.
  1879. - CONFIG_ENV_OFFSET:
  1880. - CONFIG_ENV_ADDR:
  1881. - CONFIG_ENV_SIZE:
  1882. These three #defines specify the offset and size of the
  1883. environment area within the total memory of your DataFlash placed
  1884. at the specified address.
  1885. - CONFIG_ENV_IS_IN_NAND:
  1886. Define this if you have a NAND device which you want to use
  1887. for the environment.
  1888. - CONFIG_ENV_OFFSET:
  1889. - CONFIG_ENV_SIZE:
  1890. These two #defines specify the offset and size of the environment
  1891. area within the first NAND device.
  1892. - CONFIG_ENV_OFFSET_REDUND
  1893. This setting describes a second storage area of CONFIG_ENV_SIZE
  1894. size used to hold a redundant copy of the environment data,
  1895. so that there is a valid backup copy in case there is a
  1896. power failure during a "saveenv" operation.
  1897. Note: CONFIG_ENV_OFFSET and CONFIG_ENV_OFFSET_REDUND must be aligned
  1898. to a block boundary, and CONFIG_ENV_SIZE must be a multiple of
  1899. the NAND devices block size.
  1900. - CONFIG_NAND_ENV_DST
  1901. Defines address in RAM to which the nand_spl code should copy the
  1902. environment. If redundant environment is used, it will be copied to
  1903. CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
  1904. - CONFIG_SYS_SPI_INIT_OFFSET
  1905. Defines offset to the initial SPI buffer area in DPRAM. The
  1906. area is used at an early stage (ROM part) if the environment
  1907. is configured to reside in the SPI EEPROM: We need a 520 byte
  1908. scratch DPRAM area. It is used between the two initialization
  1909. calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
  1910. to be a good choice since it makes it far enough from the
  1911. start of the data area as well as from the stack pointer.
  1912. Please note that the environment is read-only until the monitor
  1913. has been relocated to RAM and a RAM copy of the environment has been
  1914. created; also, when using EEPROM you will have to use getenv_r()
  1915. until then to read environment variables.
  1916. The environment is protected by a CRC32 checksum. Before the monitor
  1917. is relocated into RAM, as a result of a bad CRC you will be working
  1918. with the compiled-in default environment - *silently*!!! [This is
  1919. necessary, because the first environment variable we need is the
  1920. "baudrate" setting for the console - if we have a bad CRC, we don't
  1921. have any device yet where we could complain.]
  1922. Note: once the monitor has been relocated, then it will complain if
  1923. the default environment is used; a new CRC is computed as soon as you
  1924. use the "saveenv" command to store a valid environment.
  1925. - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
  1926. Echo the inverted Ethernet link state to the fault LED.
  1927. Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
  1928. also needs to be defined.
  1929. - CONFIG_SYS_FAULT_MII_ADDR:
  1930. MII address of the PHY to check for the Ethernet link state.
  1931. - CONFIG_NS16550_MIN_FUNCTIONS:
  1932. Define this if you desire to only have use of the NS16550_init
  1933. and NS16550_putc functions for the serial driver located at
  1934. drivers/serial/ns16550.c. This option is useful for saving
  1935. space for already greatly restricted images, including but not
  1936. limited to NAND_SPL configurations.
  1937. Low Level (hardware related) configuration options:
  1938. ---------------------------------------------------
  1939. - CONFIG_SYS_CACHELINE_SIZE:
  1940. Cache Line Size of the CPU.
  1941. - CONFIG_SYS_DEFAULT_IMMR:
  1942. Default address of the IMMR after system reset.
  1943. Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
  1944. and RPXsuper) to be able to adjust the position of
  1945. the IMMR register after a reset.
  1946. - Floppy Disk Support:
  1947. CONFIG_SYS_FDC_DRIVE_NUMBER
  1948. the default drive number (default value 0)
  1949. CONFIG_SYS_ISA_IO_STRIDE
  1950. defines the spacing between FDC chipset registers
  1951. (default value 1)
  1952. CONFIG_SYS_ISA_IO_OFFSET
  1953. defines the offset of register from address. It
  1954. depends on which part of the data bus is connected to
  1955. the FDC chipset. (default value 0)
  1956. If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
  1957. CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
  1958. default value.
  1959. if CONFIG_SYS_FDC_HW_INIT is defined, then the function
  1960. fdc_hw_init() is called at the beginning of the FDC
  1961. setup. fdc_hw_init() must be provided by the board
  1962. source code. It is used to make hardware dependant
  1963. initializations.
  1964. - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
  1965. DO NOT CHANGE unless you know exactly what you're
  1966. doing! (11-4) [MPC8xx/82xx systems only]
  1967. - CONFIG_SYS_INIT_RAM_ADDR:
  1968. Start address of memory area that can be used for
  1969. initial data and stack; please note that this must be
  1970. writable memory that is working WITHOUT special
  1971. initialization, i. e. you CANNOT use normal RAM which
  1972. will become available only after programming the
  1973. memory controller and running certain initialization
  1974. sequences.
  1975. U-Boot uses the following memory types:
  1976. - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
  1977. - MPC824X: data cache
  1978. - PPC4xx: data cache
  1979. - CONFIG_SYS_GBL_DATA_OFFSET:
  1980. Offset of the initial data structure in the memory
  1981. area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
  1982. CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
  1983. data is located at the end of the available space
  1984. (sometimes written as (CONFIG_SYS_INIT_RAM_END -
  1985. CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
  1986. below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
  1987. CONFIG_SYS_GBL_DATA_OFFSET) downward.
  1988. Note:
  1989. On the MPC824X (or other systems that use the data
  1990. cache for initial memory) the address chosen for
  1991. CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
  1992. point to an otherwise UNUSED address space between
  1993. the top of RAM and the start of the PCI space.
  1994. - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
  1995. - CONFIG_SYS_SYPCR: System Protection Control (11-9)
  1996. - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
  1997. - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
  1998. - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
  1999. - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
  2000. - CONFIG_SYS_OR_TIMING_SDRAM:
  2001. SDRAM timing
  2002. - CONFIG_SYS_MAMR_PTA:
  2003. periodic timer for refresh
  2004. - CONFIG_SYS_DER: Debug Event Register (37-47)
  2005. - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
  2006. CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
  2007. CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
  2008. CONFIG_SYS_BR1_PRELIM:
  2009. Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
  2010. - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
  2011. CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
  2012. CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
  2013. Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
  2014. - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
  2015. CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
  2016. Machine Mode Register and Memory Periodic Timer
  2017. Prescaler definitions (SDRAM timing)
  2018. - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
  2019. enable I2C microcode relocation patch (MPC8xx);
  2020. define relocation offset in DPRAM [DSP2]
  2021. - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
  2022. enable SMC microcode relocation patch (MPC8xx);
  2023. define relocation offset in DPRAM [SMC1]
  2024. - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
  2025. enable SPI microcode relocation patch (MPC8xx);
  2026. define relocation offset in DPRAM [SCC4]
  2027. - CONFIG_SYS_USE_OSCCLK:
  2028. Use OSCM clock mode on MBX8xx board. Be careful,
  2029. wrong setting might damage your board. Read
  2030. doc/README.MBX before setting this variable!
  2031. - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
  2032. Offset of the bootmode word in DPRAM used by post
  2033. (Power On Self Tests). This definition overrides
  2034. #define'd default value in commproc.h resp.
  2035. cpm_8260.h.
  2036. - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
  2037. CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
  2038. CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
  2039. CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
  2040. CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
  2041. CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
  2042. CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
  2043. CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
  2044. Overrides the default PCI memory map in cpu/mpc8260/pci.c if set.
  2045. - CONFIG_PCI_DISABLE_PCIE:
  2046. Disable PCI-Express on systems where it is supported but not
  2047. required.
  2048. - CONFIG_SPD_EEPROM
  2049. Get DDR timing information from an I2C EEPROM. Common
  2050. with pluggable memory modules such as SODIMMs
  2051. SPD_EEPROM_ADDRESS
  2052. I2C address of the SPD EEPROM
  2053. - CONFIG_SYS_SPD_BUS_NUM
  2054. If SPD EEPROM is on an I2C bus other than the first
  2055. one, specify here. Note that the value must resolve
  2056. to something your driver can deal with.
  2057. - CONFIG_SYS_83XX_DDR_USES_CS0
  2058. Only for 83xx systems. If specified, then DDR should
  2059. be configured using CS0 and CS1 instead of CS2 and CS3.
  2060. - CONFIG_ETHER_ON_FEC[12]
  2061. Define to enable FEC[12] on a 8xx series processor.
  2062. - CONFIG_FEC[12]_PHY
  2063. Define to the hardcoded PHY address which corresponds
  2064. to the given FEC; i. e.
  2065. #define CONFIG_FEC1_PHY 4
  2066. means that the PHY with address 4 is connected to FEC1
  2067. When set to -1, means to probe for first available.
  2068. - CONFIG_FEC[12]_PHY_NORXERR
  2069. The PHY does not have a RXERR line (RMII only).
  2070. (so program the FEC to ignore it).
  2071. - CONFIG_RMII
  2072. Enable RMII mode for all FECs.
  2073. Note that this is a global option, we can't
  2074. have one FEC in standard MII mode and another in RMII mode.
  2075. - CONFIG_CRC32_VERIFY
  2076. Add a verify option to the crc32 command.
  2077. The syntax is:
  2078. => crc32 -v <address> <count> <crc32>
  2079. Where address/count indicate a memory area
  2080. and crc32 is the correct crc32 which the
  2081. area should have.
  2082. - CONFIG_LOOPW
  2083. Add the "loopw" memory command. This only takes effect if
  2084. the memory commands are activated globally (CONFIG_CMD_MEM).
  2085. - CONFIG_MX_CYCLIC
  2086. Add the "mdc" and "mwc" memory commands. These are cyclic
  2087. "md/mw" commands.
  2088. Examples:
  2089. => mdc.b 10 4 500
  2090. This command will print 4 bytes (10,11,12,13) each 500 ms.
  2091. => mwc.l 100 12345678 10
  2092. This command will write 12345678 to address 100 all 10 ms.
  2093. This only takes effect if the memory commands are activated
  2094. globally (CONFIG_CMD_MEM).
  2095. - CONFIG_SKIP_LOWLEVEL_INIT
  2096. - CONFIG_SKIP_RELOCATE_UBOOT
  2097. [ARM only] If these variables are defined, then
  2098. certain low level initializations (like setting up
  2099. the memory controller) are omitted and/or U-Boot does
  2100. not relocate itself into RAM.
  2101. Normally these variables MUST NOT be defined. The
  2102. only exception is when U-Boot is loaded (to RAM) by
  2103. some other boot loader or by a debugger which
  2104. performs these initializations itself.
  2105. - CONFIG_PRELOADER
  2106. Modifies the behaviour of start.S when compiling a loader
  2107. that is executed before the actual U-Boot. E.g. when
  2108. compiling a NAND SPL.
  2109. Building the Software:
  2110. ======================
  2111. Building U-Boot has been tested in several native build environments
  2112. and in many different cross environments. Of course we cannot support
  2113. all possibly existing versions of cross development tools in all
  2114. (potentially obsolete) versions. In case of tool chain problems we
  2115. recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
  2116. which is extensively used to build and test U-Boot.
  2117. If you are not using a native environment, it is assumed that you
  2118. have GNU cross compiling tools available in your path. In this case,
  2119. you must set the environment variable CROSS_COMPILE in your shell.
  2120. Note that no changes to the Makefile or any other source files are
  2121. necessary. For example using the ELDK on a 4xx CPU, please enter:
  2122. $ CROSS_COMPILE=ppc_4xx-
  2123. $ export CROSS_COMPILE
  2124. Note: If you wish to generate Windows versions of the utilities in
  2125. the tools directory you can use the MinGW toolchain
  2126. (http://www.mingw.org). Set your HOST tools to the MinGW
  2127. toolchain and execute 'make tools'. For example:
  2128. $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
  2129. Binaries such as tools/mkimage.exe will be created which can
  2130. be executed on computers running Windows.
  2131. U-Boot is intended to be simple to build. After installing the
  2132. sources you must configure U-Boot for one specific board type. This
  2133. is done by typing:
  2134. make NAME_config
  2135. where "NAME_config" is the name of one of the existing configu-
  2136. rations; see the main Makefile for supported names.
  2137. Note: for some board special configuration names may exist; check if
  2138. additional information is available from the board vendor; for
  2139. instance, the TQM823L systems are available without (standard)
  2140. or with LCD support. You can select such additional "features"
  2141. when choosing the configuration, i. e.
  2142. make TQM823L_config
  2143. - will configure for a plain TQM823L, i. e. no LCD support
  2144. make TQM823L_LCD_config
  2145. - will configure for a TQM823L with U-Boot console on LCD
  2146. etc.
  2147. Finally, type "make all", and you should get some working U-Boot
  2148. images ready for download to / installation on your system:
  2149. - "u-boot.bin" is a raw binary image
  2150. - "u-boot" is an image in ELF binary format
  2151. - "u-boot.srec" is in Motorola S-Record format
  2152. By default the build is performed locally and the objects are saved
  2153. in the source directory. One of the two methods can be used to change
  2154. this behavior and build U-Boot to some external directory:
  2155. 1. Add O= to the make command line invocations:
  2156. make O=/tmp/build distclean
  2157. make O=/tmp/build NAME_config
  2158. make O=/tmp/build all
  2159. 2. Set environment variable BUILD_DIR to point to the desired location:
  2160. export BUILD_DIR=/tmp/build
  2161. make distclean
  2162. make NAME_config
  2163. make all
  2164. Note that the command line "O=" setting overrides the BUILD_DIR environment
  2165. variable.
  2166. Please be aware that the Makefiles assume you are using GNU make, so
  2167. for instance on NetBSD you might need to use "gmake" instead of
  2168. native "make".
  2169. If the system board that you have is not listed, then you will need
  2170. to port U-Boot to your hardware platform. To do this, follow these
  2171. steps:
  2172. 1. Add a new configuration option for your board to the toplevel
  2173. "Makefile" and to the "MAKEALL" script, using the existing
  2174. entries as examples. Note that here and at many other places
  2175. boards and other names are listed in alphabetical sort order. Please
  2176. keep this order.
  2177. 2. Create a new directory to hold your board specific code. Add any
  2178. files you need. In your board directory, you will need at least
  2179. the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
  2180. 3. Create a new configuration file "include/configs/<board>.h" for
  2181. your board
  2182. 3. If you're porting U-Boot to a new CPU, then also create a new
  2183. directory to hold your CPU specific code. Add any files you need.
  2184. 4. Run "make <board>_config" with your new name.
  2185. 5. Type "make", and you should get a working "u-boot.srec" file
  2186. to be installed on your target system.
  2187. 6. Debug and solve any problems that might arise.
  2188. [Of course, this last step is much harder than it sounds.]
  2189. Testing of U-Boot Modifications, Ports to New Hardware, etc.:
  2190. ==============================================================
  2191. If you have modified U-Boot sources (for instance added a new board
  2192. or support for new devices, a new CPU, etc.) you are expected to
  2193. provide feedback to the other developers. The feedback normally takes
  2194. the form of a "patch", i. e. a context diff against a certain (latest
  2195. official or latest in the git repository) version of U-Boot sources.
  2196. But before you submit such a patch, please verify that your modifi-
  2197. cation did not break existing code. At least make sure that *ALL* of
  2198. the supported boards compile WITHOUT ANY compiler warnings. To do so,
  2199. just run the "MAKEALL" script, which will configure and build U-Boot
  2200. for ALL supported system. Be warned, this will take a while. You can
  2201. select which (cross) compiler to use by passing a `CROSS_COMPILE'
  2202. environment variable to the script, i. e. to use the ELDK cross tools
  2203. you can type
  2204. CROSS_COMPILE=ppc_8xx- MAKEALL
  2205. or to build on a native PowerPC system you can type
  2206. CROSS_COMPILE=' ' MAKEALL
  2207. When using the MAKEALL script, the default behaviour is to build
  2208. U-Boot in the source directory. This location can be changed by
  2209. setting the BUILD_DIR environment variable. Also, for each target
  2210. built, the MAKEALL script saves two log files (<target>.ERR and
  2211. <target>.MAKEALL) in the <source dir>/LOG directory. This default
  2212. location can be changed by setting the MAKEALL_LOGDIR environment
  2213. variable. For example:
  2214. export BUILD_DIR=/tmp/build
  2215. export MAKEALL_LOGDIR=/tmp/log
  2216. CROSS_COMPILE=ppc_8xx- MAKEALL
  2217. With the above settings build objects are saved in the /tmp/build,
  2218. log files are saved in the /tmp/log and the source tree remains clean
  2219. during the whole build process.
  2220. See also "U-Boot Porting Guide" below.
  2221. Monitor Commands - Overview:
  2222. ============================
  2223. go - start application at address 'addr'
  2224. run - run commands in an environment variable
  2225. bootm - boot application image from memory
  2226. bootp - boot image via network using BootP/TFTP protocol
  2227. tftpboot- boot image via network using TFTP protocol
  2228. and env variables "ipaddr" and "serverip"
  2229. (and eventually "gatewayip")
  2230. rarpboot- boot image via network using RARP/TFTP protocol
  2231. diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
  2232. loads - load S-Record file over serial line
  2233. loadb - load binary file over serial line (kermit mode)
  2234. md - memory display
  2235. mm - memory modify (auto-incrementing)
  2236. nm - memory modify (constant address)
  2237. mw - memory write (fill)
  2238. cp - memory copy
  2239. cmp - memory compare
  2240. crc32 - checksum calculation
  2241. i2c - I2C sub-system
  2242. sspi - SPI utility commands
  2243. base - print or set address offset
  2244. printenv- print environment variables
  2245. setenv - set environment variables
  2246. saveenv - save environment variables to persistent storage
  2247. protect - enable or disable FLASH write protection
  2248. erase - erase FLASH memory
  2249. flinfo - print FLASH memory information
  2250. bdinfo - print Board Info structure
  2251. iminfo - print header information for application image
  2252. coninfo - print console devices and informations
  2253. ide - IDE sub-system
  2254. loop - infinite loop on address range
  2255. loopw - infinite write loop on address range
  2256. mtest - simple RAM test
  2257. icache - enable or disable instruction cache
  2258. dcache - enable or disable data cache
  2259. reset - Perform RESET of the CPU
  2260. echo - echo args to console
  2261. version - print monitor version
  2262. help - print online help
  2263. ? - alias for 'help'
  2264. Monitor Commands - Detailed Description:
  2265. ========================================
  2266. TODO.
  2267. For now: just type "help <command>".
  2268. Environment Variables:
  2269. ======================
  2270. U-Boot supports user configuration using Environment Variables which
  2271. can be made persistent by saving to Flash memory.
  2272. Environment Variables are set using "setenv", printed using
  2273. "printenv", and saved to Flash using "saveenv". Using "setenv"
  2274. without a value can be used to delete a variable from the
  2275. environment. As long as you don't save the environment you are
  2276. working with an in-memory copy. In case the Flash area containing the
  2277. environment is erased by accident, a default environment is provided.
  2278. Some configuration options can be set using Environment Variables:
  2279. baudrate - see CONFIG_BAUDRATE
  2280. bootdelay - see CONFIG_BOOTDELAY
  2281. bootcmd - see CONFIG_BOOTCOMMAND
  2282. bootargs - Boot arguments when booting an RTOS image
  2283. bootfile - Name of the image to load with TFTP
  2284. bootm_low - Memory range available for image processing in the bootm
  2285. command can be restricted. This variable is given as
  2286. a hexadecimal number and defines lowest address allowed
  2287. for use by the bootm command. See also "bootm_size"
  2288. environment variable. Address defined by "bootm_low" is
  2289. also the base of the initial memory mapping for the Linux
  2290. kernel -- see the description of CONFIG_SYS_BOOTMAPSZ.
  2291. bootm_size - Memory range available for image processing in the bootm
  2292. command can be restricted. This variable is given as
  2293. a hexadecimal number and defines the size of the region
  2294. allowed for use by the bootm command. See also "bootm_low"
  2295. environment variable.
  2296. updatefile - Location of the software update file on a TFTP server, used
  2297. by the automatic software update feature. Please refer to
  2298. documentation in doc/README.update for more details.
  2299. autoload - if set to "no" (any string beginning with 'n'),
  2300. "bootp" will just load perform a lookup of the
  2301. configuration from the BOOTP server, but not try to
  2302. load any image using TFTP
  2303. autostart - if set to "yes", an image loaded using the "bootp",
  2304. "rarpboot", "tftpboot" or "diskboot" commands will
  2305. be automatically started (by internally calling
  2306. "bootm")
  2307. If set to "no", a standalone image passed to the
  2308. "bootm" command will be copied to the load address
  2309. (and eventually uncompressed), but NOT be started.
  2310. This can be used to load and uncompress arbitrary
  2311. data.
  2312. i2cfast - (PPC405GP|PPC405EP only)
  2313. if set to 'y' configures Linux I2C driver for fast
  2314. mode (400kHZ). This environment variable is used in
  2315. initialization code. So, for changes to be effective
  2316. it must be saved and board must be reset.
  2317. initrd_high - restrict positioning of initrd images:
  2318. If this variable is not set, initrd images will be
  2319. copied to the highest possible address in RAM; this
  2320. is usually what you want since it allows for
  2321. maximum initrd size. If for some reason you want to
  2322. make sure that the initrd image is loaded below the
  2323. CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
  2324. variable to a value of "no" or "off" or "0".
  2325. Alternatively, you can set it to a maximum upper
  2326. address to use (U-Boot will still check that it
  2327. does not overwrite the U-Boot stack and data).
  2328. For instance, when you have a system with 16 MB
  2329. RAM, and want to reserve 4 MB from use by Linux,
  2330. you can do this by adding "mem=12M" to the value of
  2331. the "bootargs" variable. However, now you must make
  2332. sure that the initrd image is placed in the first
  2333. 12 MB as well - this can be done with
  2334. setenv initrd_high 00c00000
  2335. If you set initrd_high to 0xFFFFFFFF, this is an
  2336. indication to U-Boot that all addresses are legal
  2337. for the Linux kernel, including addresses in flash
  2338. memory. In this case U-Boot will NOT COPY the
  2339. ramdisk at all. This may be useful to reduce the
  2340. boot time on your system, but requires that this
  2341. feature is supported by your Linux kernel.
  2342. ipaddr - IP address; needed for tftpboot command
  2343. loadaddr - Default load address for commands like "bootp",
  2344. "rarpboot", "tftpboot", "loadb" or "diskboot"
  2345. loads_echo - see CONFIG_LOADS_ECHO
  2346. serverip - TFTP server IP address; needed for tftpboot command
  2347. bootretry - see CONFIG_BOOT_RETRY_TIME
  2348. bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
  2349. bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
  2350. ethprime - When CONFIG_NET_MULTI is enabled controls which
  2351. interface is used first.
  2352. ethact - When CONFIG_NET_MULTI is enabled controls which
  2353. interface is currently active. For example you
  2354. can do the following
  2355. => setenv ethact FEC ETHERNET
  2356. => ping 192.168.0.1 # traffic sent on FEC ETHERNET
  2357. => setenv ethact SCC ETHERNET
  2358. => ping 10.0.0.1 # traffic sent on SCC ETHERNET
  2359. ethrotate - When set to "no" U-Boot does not go through all
  2360. available network interfaces.
  2361. It just stays at the currently selected interface.
  2362. netretry - When set to "no" each network operation will
  2363. either succeed or fail without retrying.
  2364. When set to "once" the network operation will
  2365. fail when all the available network interfaces
  2366. are tried once without success.
  2367. Useful on scripts which control the retry operation
  2368. themselves.
  2369. npe_ucode - set load address for the NPE microcode
  2370. tftpsrcport - If this is set, the value is used for TFTP's
  2371. UDP source port.
  2372. tftpdstport - If this is set, the value is used for TFTP's UDP
  2373. destination port instead of the Well Know Port 69.
  2374. vlan - When set to a value < 4095 the traffic over
  2375. Ethernet is encapsulated/received over 802.1q
  2376. VLAN tagged frames.
  2377. The following environment variables may be used and automatically
  2378. updated by the network boot commands ("bootp" and "rarpboot"),
  2379. depending the information provided by your boot server:
  2380. bootfile - see above
  2381. dnsip - IP address of your Domain Name Server
  2382. dnsip2 - IP address of your secondary Domain Name Server
  2383. gatewayip - IP address of the Gateway (Router) to use
  2384. hostname - Target hostname
  2385. ipaddr - see above
  2386. netmask - Subnet Mask
  2387. rootpath - Pathname of the root filesystem on the NFS server
  2388. serverip - see above
  2389. There are two special Environment Variables:
  2390. serial# - contains hardware identification information such
  2391. as type string and/or serial number
  2392. ethaddr - Ethernet address
  2393. These variables can be set only once (usually during manufacturing of
  2394. the board). U-Boot refuses to delete or overwrite these variables
  2395. once they have been set once.
  2396. Further special Environment Variables:
  2397. ver - Contains the U-Boot version string as printed
  2398. with the "version" command. This variable is
  2399. readonly (see CONFIG_VERSION_VARIABLE).
  2400. Please note that changes to some configuration parameters may take
  2401. only effect after the next boot (yes, that's just like Windoze :-).
  2402. Command Line Parsing:
  2403. =====================
  2404. There are two different command line parsers available with U-Boot:
  2405. the old "simple" one, and the much more powerful "hush" shell:
  2406. Old, simple command line parser:
  2407. --------------------------------
  2408. - supports environment variables (through setenv / saveenv commands)
  2409. - several commands on one line, separated by ';'
  2410. - variable substitution using "... ${name} ..." syntax
  2411. - special characters ('$', ';') can be escaped by prefixing with '\',
  2412. for example:
  2413. setenv bootcmd bootm \${address}
  2414. - You can also escape text by enclosing in single apostrophes, for example:
  2415. setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
  2416. Hush shell:
  2417. -----------
  2418. - similar to Bourne shell, with control structures like
  2419. if...then...else...fi, for...do...done; while...do...done,
  2420. until...do...done, ...
  2421. - supports environment ("global") variables (through setenv / saveenv
  2422. commands) and local shell variables (through standard shell syntax
  2423. "name=value"); only environment variables can be used with "run"
  2424. command
  2425. General rules:
  2426. --------------
  2427. (1) If a command line (or an environment variable executed by a "run"
  2428. command) contains several commands separated by semicolon, and
  2429. one of these commands fails, then the remaining commands will be
  2430. executed anyway.
  2431. (2) If you execute several variables with one call to run (i. e.
  2432. calling run with a list of variables as arguments), any failing
  2433. command will cause "run" to terminate, i. e. the remaining
  2434. variables are not executed.
  2435. Note for Redundant Ethernet Interfaces:
  2436. =======================================
  2437. Some boards come with redundant Ethernet interfaces; U-Boot supports
  2438. such configurations and is capable of automatic selection of a
  2439. "working" interface when needed. MAC assignment works as follows:
  2440. Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
  2441. MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
  2442. "eth1addr" (=>eth1), "eth2addr", ...
  2443. If the network interface stores some valid MAC address (for instance
  2444. in SROM), this is used as default address if there is NO correspon-
  2445. ding setting in the environment; if the corresponding environment
  2446. variable is set, this overrides the settings in the card; that means:
  2447. o If the SROM has a valid MAC address, and there is no address in the
  2448. environment, the SROM's address is used.
  2449. o If there is no valid address in the SROM, and a definition in the
  2450. environment exists, then the value from the environment variable is
  2451. used.
  2452. o If both the SROM and the environment contain a MAC address, and
  2453. both addresses are the same, this MAC address is used.
  2454. o If both the SROM and the environment contain a MAC address, and the
  2455. addresses differ, the value from the environment is used and a
  2456. warning is printed.
  2457. o If neither SROM nor the environment contain a MAC address, an error
  2458. is raised.
  2459. Image Formats:
  2460. ==============
  2461. U-Boot is capable of booting (and performing other auxiliary operations on)
  2462. images in two formats:
  2463. New uImage format (FIT)
  2464. -----------------------
  2465. Flexible and powerful format based on Flattened Image Tree -- FIT (similar
  2466. to Flattened Device Tree). It allows the use of images with multiple
  2467. components (several kernels, ramdisks, etc.), with contents protected by
  2468. SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
  2469. Old uImage format
  2470. -----------------
  2471. Old image format is based on binary files which can be basically anything,
  2472. preceded by a special header; see the definitions in include/image.h for
  2473. details; basically, the header defines the following image properties:
  2474. * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
  2475. 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
  2476. LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
  2477. Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
  2478. INTEGRITY).
  2479. * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
  2480. IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
  2481. Currently supported: ARM, AVR32, Intel x86, MIPS, NIOS, PowerPC).
  2482. * Compression Type (uncompressed, gzip, bzip2)
  2483. * Load Address
  2484. * Entry Point
  2485. * Image Name
  2486. * Image Timestamp
  2487. The header is marked by a special Magic Number, and both the header
  2488. and the data portions of the image are secured against corruption by
  2489. CRC32 checksums.
  2490. Linux Support:
  2491. ==============
  2492. Although U-Boot should support any OS or standalone application
  2493. easily, the main focus has always been on Linux during the design of
  2494. U-Boot.
  2495. U-Boot includes many features that so far have been part of some
  2496. special "boot loader" code within the Linux kernel. Also, any
  2497. "initrd" images to be used are no longer part of one big Linux image;
  2498. instead, kernel and "initrd" are separate images. This implementation
  2499. serves several purposes:
  2500. - the same features can be used for other OS or standalone
  2501. applications (for instance: using compressed images to reduce the
  2502. Flash memory footprint)
  2503. - it becomes much easier to port new Linux kernel versions because
  2504. lots of low-level, hardware dependent stuff are done by U-Boot
  2505. - the same Linux kernel image can now be used with different "initrd"
  2506. images; of course this also means that different kernel images can
  2507. be run with the same "initrd". This makes testing easier (you don't
  2508. have to build a new "zImage.initrd" Linux image when you just
  2509. change a file in your "initrd"). Also, a field-upgrade of the
  2510. software is easier now.
  2511. Linux HOWTO:
  2512. ============
  2513. Porting Linux to U-Boot based systems:
  2514. ---------------------------------------
  2515. U-Boot cannot save you from doing all the necessary modifications to
  2516. configure the Linux device drivers for use with your target hardware
  2517. (no, we don't intend to provide a full virtual machine interface to
  2518. Linux :-).
  2519. But now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
  2520. Just make sure your machine specific header file (for instance
  2521. include/asm-ppc/tqm8xx.h) includes the same definition of the Board
  2522. Information structure as we define in include/asm-<arch>/u-boot.h,
  2523. and make sure that your definition of IMAP_ADDR uses the same value
  2524. as your U-Boot configuration in CONFIG_SYS_IMMR.
  2525. Configuring the Linux kernel:
  2526. -----------------------------
  2527. No specific requirements for U-Boot. Make sure you have some root
  2528. device (initial ramdisk, NFS) for your target system.
  2529. Building a Linux Image:
  2530. -----------------------
  2531. With U-Boot, "normal" build targets like "zImage" or "bzImage" are
  2532. not used. If you use recent kernel source, a new build target
  2533. "uImage" will exist which automatically builds an image usable by
  2534. U-Boot. Most older kernels also have support for a "pImage" target,
  2535. which was introduced for our predecessor project PPCBoot and uses a
  2536. 100% compatible format.
  2537. Example:
  2538. make TQM850L_config
  2539. make oldconfig
  2540. make dep
  2541. make uImage
  2542. The "uImage" build target uses a special tool (in 'tools/mkimage') to
  2543. encapsulate a compressed Linux kernel image with header information,
  2544. CRC32 checksum etc. for use with U-Boot. This is what we are doing:
  2545. * build a standard "vmlinux" kernel image (in ELF binary format):
  2546. * convert the kernel into a raw binary image:
  2547. ${CROSS_COMPILE}-objcopy -O binary \
  2548. -R .note -R .comment \
  2549. -S vmlinux linux.bin
  2550. * compress the binary image:
  2551. gzip -9 linux.bin
  2552. * package compressed binary image for U-Boot:
  2553. mkimage -A ppc -O linux -T kernel -C gzip \
  2554. -a 0 -e 0 -n "Linux Kernel Image" \
  2555. -d linux.bin.gz uImage
  2556. The "mkimage" tool can also be used to create ramdisk images for use
  2557. with U-Boot, either separated from the Linux kernel image, or
  2558. combined into one file. "mkimage" encapsulates the images with a 64
  2559. byte header containing information about target architecture,
  2560. operating system, image type, compression method, entry points, time
  2561. stamp, CRC32 checksums, etc.
  2562. "mkimage" can be called in two ways: to verify existing images and
  2563. print the header information, or to build new images.
  2564. In the first form (with "-l" option) mkimage lists the information
  2565. contained in the header of an existing U-Boot image; this includes
  2566. checksum verification:
  2567. tools/mkimage -l image
  2568. -l ==> list image header information
  2569. The second form (with "-d" option) is used to build a U-Boot image
  2570. from a "data file" which is used as image payload:
  2571. tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
  2572. -n name -d data_file image
  2573. -A ==> set architecture to 'arch'
  2574. -O ==> set operating system to 'os'
  2575. -T ==> set image type to 'type'
  2576. -C ==> set compression type 'comp'
  2577. -a ==> set load address to 'addr' (hex)
  2578. -e ==> set entry point to 'ep' (hex)
  2579. -n ==> set image name to 'name'
  2580. -d ==> use image data from 'datafile'
  2581. Right now, all Linux kernels for PowerPC systems use the same load
  2582. address (0x00000000), but the entry point address depends on the
  2583. kernel version:
  2584. - 2.2.x kernels have the entry point at 0x0000000C,
  2585. - 2.3.x and later kernels have the entry point at 0x00000000.
  2586. So a typical call to build a U-Boot image would read:
  2587. -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
  2588. > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
  2589. > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
  2590. > examples/uImage.TQM850L
  2591. Image Name: 2.4.4 kernel for TQM850L
  2592. Created: Wed Jul 19 02:34:59 2000
  2593. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  2594. Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
  2595. Load Address: 0x00000000
  2596. Entry Point: 0x00000000
  2597. To verify the contents of the image (or check for corruption):
  2598. -> tools/mkimage -l examples/uImage.TQM850L
  2599. Image Name: 2.4.4 kernel for TQM850L
  2600. Created: Wed Jul 19 02:34:59 2000
  2601. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  2602. Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
  2603. Load Address: 0x00000000
  2604. Entry Point: 0x00000000
  2605. NOTE: for embedded systems where boot time is critical you can trade
  2606. speed for memory and install an UNCOMPRESSED image instead: this
  2607. needs more space in Flash, but boots much faster since it does not
  2608. need to be uncompressed:
  2609. -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
  2610. -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
  2611. > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
  2612. > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
  2613. > examples/uImage.TQM850L-uncompressed
  2614. Image Name: 2.4.4 kernel for TQM850L
  2615. Created: Wed Jul 19 02:34:59 2000
  2616. Image Type: PowerPC Linux Kernel Image (uncompressed)
  2617. Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
  2618. Load Address: 0x00000000
  2619. Entry Point: 0x00000000
  2620. Similar you can build U-Boot images from a 'ramdisk.image.gz' file
  2621. when your kernel is intended to use an initial ramdisk:
  2622. -> tools/mkimage -n 'Simple Ramdisk Image' \
  2623. > -A ppc -O linux -T ramdisk -C gzip \
  2624. > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
  2625. Image Name: Simple Ramdisk Image
  2626. Created: Wed Jan 12 14:01:50 2000
  2627. Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
  2628. Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
  2629. Load Address: 0x00000000
  2630. Entry Point: 0x00000000
  2631. Installing a Linux Image:
  2632. -------------------------
  2633. To downloading a U-Boot image over the serial (console) interface,
  2634. you must convert the image to S-Record format:
  2635. objcopy -I binary -O srec examples/image examples/image.srec
  2636. The 'objcopy' does not understand the information in the U-Boot
  2637. image header, so the resulting S-Record file will be relative to
  2638. address 0x00000000. To load it to a given address, you need to
  2639. specify the target address as 'offset' parameter with the 'loads'
  2640. command.
  2641. Example: install the image to address 0x40100000 (which on the
  2642. TQM8xxL is in the first Flash bank):
  2643. => erase 40100000 401FFFFF
  2644. .......... done
  2645. Erased 8 sectors
  2646. => loads 40100000
  2647. ## Ready for S-Record download ...
  2648. ~>examples/image.srec
  2649. 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
  2650. ...
  2651. 15989 15990 15991 15992
  2652. [file transfer complete]
  2653. [connected]
  2654. ## Start Addr = 0x00000000
  2655. You can check the success of the download using the 'iminfo' command;
  2656. this includes a checksum verification so you can be sure no data
  2657. corruption happened:
  2658. => imi 40100000
  2659. ## Checking Image at 40100000 ...
  2660. Image Name: 2.2.13 for initrd on TQM850L
  2661. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  2662. Data Size: 335725 Bytes = 327 kB = 0 MB
  2663. Load Address: 00000000
  2664. Entry Point: 0000000c
  2665. Verifying Checksum ... OK
  2666. Boot Linux:
  2667. -----------
  2668. The "bootm" command is used to boot an application that is stored in
  2669. memory (RAM or Flash). In case of a Linux kernel image, the contents
  2670. of the "bootargs" environment variable is passed to the kernel as
  2671. parameters. You can check and modify this variable using the
  2672. "printenv" and "setenv" commands:
  2673. => printenv bootargs
  2674. bootargs=root=/dev/ram
  2675. => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
  2676. => printenv bootargs
  2677. bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
  2678. => bootm 40020000
  2679. ## Booting Linux kernel at 40020000 ...
  2680. Image Name: 2.2.13 for NFS on TQM850L
  2681. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  2682. Data Size: 381681 Bytes = 372 kB = 0 MB
  2683. Load Address: 00000000
  2684. Entry Point: 0000000c
  2685. Verifying Checksum ... OK
  2686. Uncompressing Kernel Image ... OK
  2687. 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
  2688. Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
  2689. time_init: decrementer frequency = 187500000/60
  2690. Calibrating delay loop... 49.77 BogoMIPS
  2691. Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
  2692. ...
  2693. If you want to boot a Linux kernel with initial RAM disk, you pass
  2694. the memory addresses of both the kernel and the initrd image (PPBCOOT
  2695. format!) to the "bootm" command:
  2696. => imi 40100000 40200000
  2697. ## Checking Image at 40100000 ...
  2698. Image Name: 2.2.13 for initrd on TQM850L
  2699. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  2700. Data Size: 335725 Bytes = 327 kB = 0 MB
  2701. Load Address: 00000000
  2702. Entry Point: 0000000c
  2703. Verifying Checksum ... OK
  2704. ## Checking Image at 40200000 ...
  2705. Image Name: Simple Ramdisk Image
  2706. Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
  2707. Data Size: 566530 Bytes = 553 kB = 0 MB
  2708. Load Address: 00000000
  2709. Entry Point: 00000000
  2710. Verifying Checksum ... OK
  2711. => bootm 40100000 40200000
  2712. ## Booting Linux kernel at 40100000 ...
  2713. Image Name: 2.2.13 for initrd on TQM850L
  2714. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  2715. Data Size: 335725 Bytes = 327 kB = 0 MB
  2716. Load Address: 00000000
  2717. Entry Point: 0000000c
  2718. Verifying Checksum ... OK
  2719. Uncompressing Kernel Image ... OK
  2720. ## Loading RAMDisk Image at 40200000 ...
  2721. Image Name: Simple Ramdisk Image
  2722. Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
  2723. Data Size: 566530 Bytes = 553 kB = 0 MB
  2724. Load Address: 00000000
  2725. Entry Point: 00000000
  2726. Verifying Checksum ... OK
  2727. Loading Ramdisk ... OK
  2728. 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
  2729. Boot arguments: root=/dev/ram
  2730. time_init: decrementer frequency = 187500000/60
  2731. Calibrating delay loop... 49.77 BogoMIPS
  2732. ...
  2733. RAMDISK: Compressed image found at block 0
  2734. VFS: Mounted root (ext2 filesystem).
  2735. bash#
  2736. Boot Linux and pass a flat device tree:
  2737. -----------
  2738. First, U-Boot must be compiled with the appropriate defines. See the section
  2739. titled "Linux Kernel Interface" above for a more in depth explanation. The
  2740. following is an example of how to start a kernel and pass an updated
  2741. flat device tree:
  2742. => print oftaddr
  2743. oftaddr=0x300000
  2744. => print oft
  2745. oft=oftrees/mpc8540ads.dtb
  2746. => tftp $oftaddr $oft
  2747. Speed: 1000, full duplex
  2748. Using TSEC0 device
  2749. TFTP from server 192.168.1.1; our IP address is 192.168.1.101
  2750. Filename 'oftrees/mpc8540ads.dtb'.
  2751. Load address: 0x300000
  2752. Loading: #
  2753. done
  2754. Bytes transferred = 4106 (100a hex)
  2755. => tftp $loadaddr $bootfile
  2756. Speed: 1000, full duplex
  2757. Using TSEC0 device
  2758. TFTP from server 192.168.1.1; our IP address is 192.168.1.2
  2759. Filename 'uImage'.
  2760. Load address: 0x200000
  2761. Loading:############
  2762. done
  2763. Bytes transferred = 1029407 (fb51f hex)
  2764. => print loadaddr
  2765. loadaddr=200000
  2766. => print oftaddr
  2767. oftaddr=0x300000
  2768. => bootm $loadaddr - $oftaddr
  2769. ## Booting image at 00200000 ...
  2770. Image Name: Linux-2.6.17-dirty
  2771. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  2772. Data Size: 1029343 Bytes = 1005.2 kB
  2773. Load Address: 00000000
  2774. Entry Point: 00000000
  2775. Verifying Checksum ... OK
  2776. Uncompressing Kernel Image ... OK
  2777. Booting using flat device tree at 0x300000
  2778. Using MPC85xx ADS machine description
  2779. Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
  2780. [snip]
  2781. More About U-Boot Image Types:
  2782. ------------------------------
  2783. U-Boot supports the following image types:
  2784. "Standalone Programs" are directly runnable in the environment
  2785. provided by U-Boot; it is expected that (if they behave
  2786. well) you can continue to work in U-Boot after return from
  2787. the Standalone Program.
  2788. "OS Kernel Images" are usually images of some Embedded OS which
  2789. will take over control completely. Usually these programs
  2790. will install their own set of exception handlers, device
  2791. drivers, set up the MMU, etc. - this means, that you cannot
  2792. expect to re-enter U-Boot except by resetting the CPU.
  2793. "RAMDisk Images" are more or less just data blocks, and their
  2794. parameters (address, size) are passed to an OS kernel that is
  2795. being started.
  2796. "Multi-File Images" contain several images, typically an OS
  2797. (Linux) kernel image and one or more data images like
  2798. RAMDisks. This construct is useful for instance when you want
  2799. to boot over the network using BOOTP etc., where the boot
  2800. server provides just a single image file, but you want to get
  2801. for instance an OS kernel and a RAMDisk image.
  2802. "Multi-File Images" start with a list of image sizes, each
  2803. image size (in bytes) specified by an "uint32_t" in network
  2804. byte order. This list is terminated by an "(uint32_t)0".
  2805. Immediately after the terminating 0 follow the images, one by
  2806. one, all aligned on "uint32_t" boundaries (size rounded up to
  2807. a multiple of 4 bytes).
  2808. "Firmware Images" are binary images containing firmware (like
  2809. U-Boot or FPGA images) which usually will be programmed to
  2810. flash memory.
  2811. "Script files" are command sequences that will be executed by
  2812. U-Boot's command interpreter; this feature is especially
  2813. useful when you configure U-Boot to use a real shell (hush)
  2814. as command interpreter.
  2815. Standalone HOWTO:
  2816. =================
  2817. One of the features of U-Boot is that you can dynamically load and
  2818. run "standalone" applications, which can use some resources of
  2819. U-Boot like console I/O functions or interrupt services.
  2820. Two simple examples are included with the sources:
  2821. "Hello World" Demo:
  2822. -------------------
  2823. 'examples/hello_world.c' contains a small "Hello World" Demo
  2824. application; it is automatically compiled when you build U-Boot.
  2825. It's configured to run at address 0x00040004, so you can play with it
  2826. like that:
  2827. => loads
  2828. ## Ready for S-Record download ...
  2829. ~>examples/hello_world.srec
  2830. 1 2 3 4 5 6 7 8 9 10 11 ...
  2831. [file transfer complete]
  2832. [connected]
  2833. ## Start Addr = 0x00040004
  2834. => go 40004 Hello World! This is a test.
  2835. ## Starting application at 0x00040004 ...
  2836. Hello World
  2837. argc = 7
  2838. argv[0] = "40004"
  2839. argv[1] = "Hello"
  2840. argv[2] = "World!"
  2841. argv[3] = "This"
  2842. argv[4] = "is"
  2843. argv[5] = "a"
  2844. argv[6] = "test."
  2845. argv[7] = "<NULL>"
  2846. Hit any key to exit ...
  2847. ## Application terminated, rc = 0x0
  2848. Another example, which demonstrates how to register a CPM interrupt
  2849. handler with the U-Boot code, can be found in 'examples/timer.c'.
  2850. Here, a CPM timer is set up to generate an interrupt every second.
  2851. The interrupt service routine is trivial, just printing a '.'
  2852. character, but this is just a demo program. The application can be
  2853. controlled by the following keys:
  2854. ? - print current values og the CPM Timer registers
  2855. b - enable interrupts and start timer
  2856. e - stop timer and disable interrupts
  2857. q - quit application
  2858. => loads
  2859. ## Ready for S-Record download ...
  2860. ~>examples/timer.srec
  2861. 1 2 3 4 5 6 7 8 9 10 11 ...
  2862. [file transfer complete]
  2863. [connected]
  2864. ## Start Addr = 0x00040004
  2865. => go 40004
  2866. ## Starting application at 0x00040004 ...
  2867. TIMERS=0xfff00980
  2868. Using timer 1
  2869. tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
  2870. Hit 'b':
  2871. [q, b, e, ?] Set interval 1000000 us
  2872. Enabling timer
  2873. Hit '?':
  2874. [q, b, e, ?] ........
  2875. tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
  2876. Hit '?':
  2877. [q, b, e, ?] .
  2878. tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
  2879. Hit '?':
  2880. [q, b, e, ?] .
  2881. tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
  2882. Hit '?':
  2883. [q, b, e, ?] .
  2884. tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
  2885. Hit 'e':
  2886. [q, b, e, ?] ...Stopping timer
  2887. Hit 'q':
  2888. [q, b, e, ?] ## Application terminated, rc = 0x0
  2889. Minicom warning:
  2890. ================
  2891. Over time, many people have reported problems when trying to use the
  2892. "minicom" terminal emulation program for serial download. I (wd)
  2893. consider minicom to be broken, and recommend not to use it. Under
  2894. Unix, I recommend to use C-Kermit for general purpose use (and
  2895. especially for kermit binary protocol download ("loadb" command), and
  2896. use "cu" for S-Record download ("loads" command).
  2897. Nevertheless, if you absolutely want to use it try adding this
  2898. configuration to your "File transfer protocols" section:
  2899. Name Program Name U/D FullScr IO-Red. Multi
  2900. X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
  2901. Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
  2902. NetBSD Notes:
  2903. =============
  2904. Starting at version 0.9.2, U-Boot supports NetBSD both as host
  2905. (build U-Boot) and target system (boots NetBSD/mpc8xx).
  2906. Building requires a cross environment; it is known to work on
  2907. NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
  2908. need gmake since the Makefiles are not compatible with BSD make).
  2909. Note that the cross-powerpc package does not install include files;
  2910. attempting to build U-Boot will fail because <machine/ansi.h> is
  2911. missing. This file has to be installed and patched manually:
  2912. # cd /usr/pkg/cross/powerpc-netbsd/include
  2913. # mkdir powerpc
  2914. # ln -s powerpc machine
  2915. # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
  2916. # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
  2917. Native builds *don't* work due to incompatibilities between native
  2918. and U-Boot include files.
  2919. Booting assumes that (the first part of) the image booted is a
  2920. stage-2 loader which in turn loads and then invokes the kernel
  2921. proper. Loader sources will eventually appear in the NetBSD source
  2922. tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
  2923. meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
  2924. Implementation Internals:
  2925. =========================
  2926. The following is not intended to be a complete description of every
  2927. implementation detail. However, it should help to understand the
  2928. inner workings of U-Boot and make it easier to port it to custom
  2929. hardware.
  2930. Initial Stack, Global Data:
  2931. ---------------------------
  2932. The implementation of U-Boot is complicated by the fact that U-Boot
  2933. starts running out of ROM (flash memory), usually without access to
  2934. system RAM (because the memory controller is not initialized yet).
  2935. This means that we don't have writable Data or BSS segments, and BSS
  2936. is not initialized as zero. To be able to get a C environment working
  2937. at all, we have to allocate at least a minimal stack. Implementation
  2938. options for this are defined and restricted by the CPU used: Some CPU
  2939. models provide on-chip memory (like the IMMR area on MPC8xx and
  2940. MPC826x processors), on others (parts of) the data cache can be
  2941. locked as (mis-) used as memory, etc.
  2942. Chris Hallinan posted a good summary of these issues to the
  2943. U-Boot mailing list:
  2944. Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
  2945. From: "Chris Hallinan" <clh@net1plus.com>
  2946. Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
  2947. ...
  2948. Correct me if I'm wrong, folks, but the way I understand it
  2949. is this: Using DCACHE as initial RAM for Stack, etc, does not
  2950. require any physical RAM backing up the cache. The cleverness
  2951. is that the cache is being used as a temporary supply of
  2952. necessary storage before the SDRAM controller is setup. It's
  2953. beyond the scope of this list to explain the details, but you
  2954. can see how this works by studying the cache architecture and
  2955. operation in the architecture and processor-specific manuals.
  2956. OCM is On Chip Memory, which I believe the 405GP has 4K. It
  2957. is another option for the system designer to use as an
  2958. initial stack/RAM area prior to SDRAM being available. Either
  2959. option should work for you. Using CS 4 should be fine if your
  2960. board designers haven't used it for something that would
  2961. cause you grief during the initial boot! It is frequently not
  2962. used.
  2963. CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
  2964. with your processor/board/system design. The default value
  2965. you will find in any recent u-boot distribution in
  2966. walnut.h should work for you. I'd set it to a value larger
  2967. than your SDRAM module. If you have a 64MB SDRAM module, set
  2968. it above 400_0000. Just make sure your board has no resources
  2969. that are supposed to respond to that address! That code in
  2970. start.S has been around a while and should work as is when
  2971. you get the config right.
  2972. -Chris Hallinan
  2973. DS4.COM, Inc.
  2974. It is essential to remember this, since it has some impact on the C
  2975. code for the initialization procedures:
  2976. * Initialized global data (data segment) is read-only. Do not attempt
  2977. to write it.
  2978. * Do not use any uninitialized global data (or implicitely initialized
  2979. as zero data - BSS segment) at all - this is undefined, initiali-
  2980. zation is performed later (when relocating to RAM).
  2981. * Stack space is very limited. Avoid big data buffers or things like
  2982. that.
  2983. Having only the stack as writable memory limits means we cannot use
  2984. normal global data to share information beween the code. But it
  2985. turned out that the implementation of U-Boot can be greatly
  2986. simplified by making a global data structure (gd_t) available to all
  2987. functions. We could pass a pointer to this data as argument to _all_
  2988. functions, but this would bloat the code. Instead we use a feature of
  2989. the GCC compiler (Global Register Variables) to share the data: we
  2990. place a pointer (gd) to the global data into a register which we
  2991. reserve for this purpose.
  2992. When choosing a register for such a purpose we are restricted by the
  2993. relevant (E)ABI specifications for the current architecture, and by
  2994. GCC's implementation.
  2995. For PowerPC, the following registers have specific use:
  2996. R1: stack pointer
  2997. R2: reserved for system use
  2998. R3-R4: parameter passing and return values
  2999. R5-R10: parameter passing
  3000. R13: small data area pointer
  3001. R30: GOT pointer
  3002. R31: frame pointer
  3003. (U-Boot also uses R14 as internal GOT pointer.)
  3004. ==> U-Boot will use R2 to hold a pointer to the global data
  3005. Note: on PPC, we could use a static initializer (since the
  3006. address of the global data structure is known at compile time),
  3007. but it turned out that reserving a register results in somewhat
  3008. smaller code - although the code savings are not that big (on
  3009. average for all boards 752 bytes for the whole U-Boot image,
  3010. 624 text + 127 data).
  3011. On Blackfin, the normal C ABI (except for P3) is followed as documented here:
  3012. http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
  3013. ==> U-Boot will use P3 to hold a pointer to the global data
  3014. On ARM, the following registers are used:
  3015. R0: function argument word/integer result
  3016. R1-R3: function argument word
  3017. R9: GOT pointer
  3018. R10: stack limit (used only if stack checking if enabled)
  3019. R11: argument (frame) pointer
  3020. R12: temporary workspace
  3021. R13: stack pointer
  3022. R14: link register
  3023. R15: program counter
  3024. ==> U-Boot will use R8 to hold a pointer to the global data
  3025. NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
  3026. or current versions of GCC may "optimize" the code too much.
  3027. Memory Management:
  3028. ------------------
  3029. U-Boot runs in system state and uses physical addresses, i.e. the
  3030. MMU is not used either for address mapping nor for memory protection.
  3031. The available memory is mapped to fixed addresses using the memory
  3032. controller. In this process, a contiguous block is formed for each
  3033. memory type (Flash, SDRAM, SRAM), even when it consists of several
  3034. physical memory banks.
  3035. U-Boot is installed in the first 128 kB of the first Flash bank (on
  3036. TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
  3037. booting and sizing and initializing DRAM, the code relocates itself
  3038. to the upper end of DRAM. Immediately below the U-Boot code some
  3039. memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
  3040. configuration setting]. Below that, a structure with global Board
  3041. Info data is placed, followed by the stack (growing downward).
  3042. Additionally, some exception handler code is copied to the low 8 kB
  3043. of DRAM (0x00000000 ... 0x00001FFF).
  3044. So a typical memory configuration with 16 MB of DRAM could look like
  3045. this:
  3046. 0x0000 0000 Exception Vector code
  3047. :
  3048. 0x0000 1FFF
  3049. 0x0000 2000 Free for Application Use
  3050. :
  3051. :
  3052. :
  3053. :
  3054. 0x00FB FF20 Monitor Stack (Growing downward)
  3055. 0x00FB FFAC Board Info Data and permanent copy of global data
  3056. 0x00FC 0000 Malloc Arena
  3057. :
  3058. 0x00FD FFFF
  3059. 0x00FE 0000 RAM Copy of Monitor Code
  3060. ... eventually: LCD or video framebuffer
  3061. ... eventually: pRAM (Protected RAM - unchanged by reset)
  3062. 0x00FF FFFF [End of RAM]
  3063. System Initialization:
  3064. ----------------------
  3065. In the reset configuration, U-Boot starts at the reset entry point
  3066. (on most PowerPC systems at address 0x00000100). Because of the reset
  3067. configuration for CS0# this is a mirror of the onboard Flash memory.
  3068. To be able to re-map memory U-Boot then jumps to its link address.
  3069. To be able to implement the initialization code in C, a (small!)
  3070. initial stack is set up in the internal Dual Ported RAM (in case CPUs
  3071. which provide such a feature like MPC8xx or MPC8260), or in a locked
  3072. part of the data cache. After that, U-Boot initializes the CPU core,
  3073. the caches and the SIU.
  3074. Next, all (potentially) available memory banks are mapped using a
  3075. preliminary mapping. For example, we put them on 512 MB boundaries
  3076. (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
  3077. on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
  3078. programmed for SDRAM access. Using the temporary configuration, a
  3079. simple memory test is run that determines the size of the SDRAM
  3080. banks.
  3081. When there is more than one SDRAM bank, and the banks are of
  3082. different size, the largest is mapped first. For equal size, the first
  3083. bank (CS2#) is mapped first. The first mapping is always for address
  3084. 0x00000000, with any additional banks following immediately to create
  3085. contiguous memory starting from 0.
  3086. Then, the monitor installs itself at the upper end of the SDRAM area
  3087. and allocates memory for use by malloc() and for the global Board
  3088. Info data; also, the exception vector code is copied to the low RAM
  3089. pages, and the final stack is set up.
  3090. Only after this relocation will you have a "normal" C environment;
  3091. until that you are restricted in several ways, mostly because you are
  3092. running from ROM, and because the code will have to be relocated to a
  3093. new address in RAM.
  3094. U-Boot Porting Guide:
  3095. ----------------------
  3096. [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
  3097. list, October 2002]
  3098. int main(int argc, char *argv[])
  3099. {
  3100. sighandler_t no_more_time;
  3101. signal(SIGALRM, no_more_time);
  3102. alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
  3103. if (available_money > available_manpower) {
  3104. Pay consultant to port U-Boot;
  3105. return 0;
  3106. }
  3107. Download latest U-Boot source;
  3108. Subscribe to u-boot mailing list;
  3109. if (clueless)
  3110. email("Hi, I am new to U-Boot, how do I get started?");
  3111. while (learning) {
  3112. Read the README file in the top level directory;
  3113. Read http://www.denx.de/twiki/bin/view/DULG/Manual;
  3114. Read applicable doc/*.README;
  3115. Read the source, Luke;
  3116. /* find . -name "*.[chS]" | xargs grep -i <keyword> */
  3117. }
  3118. if (available_money > toLocalCurrency ($2500))
  3119. Buy a BDI3000;
  3120. else
  3121. Add a lot of aggravation and time;
  3122. if (a similar board exists) { /* hopefully... */
  3123. cp -a board/<similar> board/<myboard>
  3124. cp include/configs/<similar>.h include/configs/<myboard>.h
  3125. } else {
  3126. Create your own board support subdirectory;
  3127. Create your own board include/configs/<myboard>.h file;
  3128. }
  3129. Edit new board/<myboard> files
  3130. Edit new include/configs/<myboard>.h
  3131. while (!accepted) {
  3132. while (!running) {
  3133. do {
  3134. Add / modify source code;
  3135. } until (compiles);
  3136. Debug;
  3137. if (clueless)
  3138. email("Hi, I am having problems...");
  3139. }
  3140. Send patch file to the U-Boot email list;
  3141. if (reasonable critiques)
  3142. Incorporate improvements from email list code review;
  3143. else
  3144. Defend code as written;
  3145. }
  3146. return 0;
  3147. }
  3148. void no_more_time (int sig)
  3149. {
  3150. hire_a_guru();
  3151. }
  3152. Coding Standards:
  3153. -----------------
  3154. All contributions to U-Boot should conform to the Linux kernel
  3155. coding style; see the file "Documentation/CodingStyle" and the script
  3156. "scripts/Lindent" in your Linux kernel source directory. In sources
  3157. originating from U-Boot a style corresponding to "Lindent -pcs" (adding
  3158. spaces before parameters to function calls) is actually used.
  3159. Source files originating from a different project (for example the
  3160. MTD subsystem) are generally exempt from these guidelines and are not
  3161. reformated to ease subsequent migration to newer versions of those
  3162. sources.
  3163. Please note that U-Boot is implemented in C (and to some small parts in
  3164. Assembler); no C++ is used, so please do not use C++ style comments (//)
  3165. in your code.
  3166. Please also stick to the following formatting rules:
  3167. - remove any trailing white space
  3168. - use TAB characters for indentation, not spaces
  3169. - make sure NOT to use DOS '\r\n' line feeds
  3170. - do not add more than 2 empty lines to source files
  3171. - do not add trailing empty lines to source files
  3172. Submissions which do not conform to the standards may be returned
  3173. with a request to reformat the changes.
  3174. Submitting Patches:
  3175. -------------------
  3176. Since the number of patches for U-Boot is growing, we need to
  3177. establish some rules. Submissions which do not conform to these rules
  3178. may be rejected, even when they contain important and valuable stuff.
  3179. Please see http://www.denx.de/wiki/U-Boot/Patches for details.
  3180. Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
  3181. see http://lists.denx.de/mailman/listinfo/u-boot
  3182. When you send a patch, please include the following information with
  3183. it:
  3184. * For bug fixes: a description of the bug and how your patch fixes
  3185. this bug. Please try to include a way of demonstrating that the
  3186. patch actually fixes something.
  3187. * For new features: a description of the feature and your
  3188. implementation.
  3189. * A CHANGELOG entry as plaintext (separate from the patch)
  3190. * For major contributions, your entry to the CREDITS file
  3191. * When you add support for a new board, don't forget to add this
  3192. board to the MAKEALL script, too.
  3193. * If your patch adds new configuration options, don't forget to
  3194. document these in the README file.
  3195. * The patch itself. If you are using git (which is *strongly*
  3196. recommended) you can easily generate the patch using the
  3197. "git-format-patch". If you then use "git-send-email" to send it to
  3198. the U-Boot mailing list, you will avoid most of the common problems
  3199. with some other mail clients.
  3200. If you cannot use git, use "diff -purN OLD NEW". If your version of
  3201. diff does not support these options, then get the latest version of
  3202. GNU diff.
  3203. The current directory when running this command shall be the parent
  3204. directory of the U-Boot source tree (i. e. please make sure that
  3205. your patch includes sufficient directory information for the
  3206. affected files).
  3207. We prefer patches as plain text. MIME attachments are discouraged,
  3208. and compressed attachments must not be used.
  3209. * If one logical set of modifications affects or creates several
  3210. files, all these changes shall be submitted in a SINGLE patch file.
  3211. * Changesets that contain different, unrelated modifications shall be
  3212. submitted as SEPARATE patches, one patch per changeset.
  3213. Notes:
  3214. * Before sending the patch, run the MAKEALL script on your patched
  3215. source tree and make sure that no errors or warnings are reported
  3216. for any of the boards.
  3217. * Keep your modifications to the necessary minimum: A patch
  3218. containing several unrelated changes or arbitrary reformats will be
  3219. returned with a request to re-formatting / split it.
  3220. * If you modify existing code, make sure that your new code does not
  3221. add to the memory footprint of the code ;-) Small is beautiful!
  3222. When adding new features, these should compile conditionally only
  3223. (using #ifdef), and the resulting code with the new feature
  3224. disabled must not need more memory than the old code without your
  3225. modification.
  3226. * Remember that there is a size limit of 100 kB per message on the
  3227. u-boot mailing list. Bigger patches will be moderated. If they are
  3228. reasonable and not too big, they will be acknowledged. But patches
  3229. bigger than the size limit should be avoided.