README 134 KB

1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283848586878889909192939495969798991001011021031041051061071081091101111121131141151161171181191201211221231241251261271281291301311321331341351361371381391401411421431441451461471481491501511521531541551561571581591601611621631641651661671681691701711721731741751761771781791801811821831841851861871881891901911921931941951961971981992002012022032042052062072082092102112122132142152162172182192202212222232242252262272282292302312322332342352362372382392402412422432442452462472482492502512522532542552562572582592602612622632642652662672682692702712722732742752762772782792802812822832842852862872882892902912922932942952962972982993003013023033043053063073083093103113123133143153163173183193203213223233243253263273283293303313323333343353363373383393403413423433443453463473483493503513523533543553563573583593603613623633643653663673683693703713723733743753763773783793803813823833843853863873883893903913923933943953963973983994004014024034044054064074084094104114124134144154164174184194204214224234244254264274284294304314324334344354364374384394404414424434444454464474484494504514524534544554564574584594604614624634644654664674684694704714724734744754764774784794804814824834844854864874884894904914924934944954964974984995005015025035045055065075085095105115125135145155165175185195205215225235245255265275285295305315325335345355365375385395405415425435445455465475485495505515525535545555565575585595605615625635645655665675685695705715725735745755765775785795805815825835845855865875885895905915925935945955965975985996006016026036046056066076086096106116126136146156166176186196206216226236246256266276286296306316326336346356366376386396406416426436446456466476486496506516526536546556566576586596606616626636646656666676686696706716726736746756766776786796806816826836846856866876886896906916926936946956966976986997007017027037047057067077087097107117127137147157167177187197207217227237247257267277287297307317327337347357367377387397407417427437447457467477487497507517527537547557567577587597607617627637647657667677687697707717727737747757767777787797807817827837847857867877887897907917927937947957967977987998008018028038048058068078088098108118128138148158168178188198208218228238248258268278288298308318328338348358368378388398408418428438448458468478488498508518528538548558568578588598608618628638648658668678688698708718728738748758768778788798808818828838848858868878888898908918928938948958968978988999009019029039049059069079089099109119129139149159169179189199209219229239249259269279289299309319329339349359369379389399409419429439449459469479489499509519529539549559569579589599609619629639649659669679689699709719729739749759769779789799809819829839849859869879889899909919929939949959969979989991000100110021003100410051006100710081009101010111012101310141015101610171018101910201021102210231024102510261027102810291030103110321033103410351036103710381039104010411042104310441045104610471048104910501051105210531054105510561057105810591060106110621063106410651066106710681069107010711072107310741075107610771078107910801081108210831084108510861087108810891090109110921093109410951096109710981099110011011102110311041105110611071108110911101111111211131114111511161117111811191120112111221123112411251126112711281129113011311132113311341135113611371138113911401141114211431144114511461147114811491150115111521153115411551156115711581159116011611162116311641165116611671168116911701171117211731174117511761177117811791180118111821183118411851186118711881189119011911192119311941195119611971198119912001201120212031204120512061207120812091210121112121213121412151216121712181219122012211222122312241225122612271228122912301231123212331234123512361237123812391240124112421243124412451246124712481249125012511252125312541255125612571258125912601261126212631264126512661267126812691270127112721273127412751276127712781279128012811282128312841285128612871288128912901291129212931294129512961297129812991300130113021303130413051306130713081309131013111312131313141315131613171318131913201321132213231324132513261327132813291330133113321333133413351336133713381339134013411342134313441345134613471348134913501351135213531354135513561357135813591360136113621363136413651366136713681369137013711372137313741375137613771378137913801381138213831384138513861387138813891390139113921393139413951396139713981399140014011402140314041405140614071408140914101411141214131414141514161417141814191420142114221423142414251426142714281429143014311432143314341435143614371438143914401441144214431444144514461447144814491450145114521453145414551456145714581459146014611462146314641465146614671468146914701471147214731474147514761477147814791480148114821483148414851486148714881489149014911492149314941495149614971498149915001501150215031504150515061507150815091510151115121513151415151516151715181519152015211522152315241525152615271528152915301531153215331534153515361537153815391540154115421543154415451546154715481549155015511552155315541555155615571558155915601561156215631564156515661567156815691570157115721573157415751576157715781579158015811582158315841585158615871588158915901591159215931594159515961597159815991600160116021603160416051606160716081609161016111612161316141615161616171618161916201621162216231624162516261627162816291630163116321633163416351636163716381639164016411642164316441645164616471648164916501651165216531654165516561657165816591660166116621663166416651666166716681669167016711672167316741675167616771678167916801681168216831684168516861687168816891690169116921693169416951696169716981699170017011702170317041705170617071708170917101711171217131714171517161717171817191720172117221723172417251726172717281729173017311732173317341735173617371738173917401741174217431744174517461747174817491750175117521753175417551756175717581759176017611762176317641765176617671768176917701771177217731774177517761777177817791780178117821783178417851786178717881789179017911792179317941795179617971798179918001801180218031804180518061807180818091810181118121813181418151816181718181819182018211822182318241825182618271828182918301831183218331834183518361837183818391840184118421843184418451846184718481849185018511852185318541855185618571858185918601861186218631864186518661867186818691870187118721873187418751876187718781879188018811882188318841885188618871888188918901891189218931894189518961897189818991900190119021903190419051906190719081909191019111912191319141915191619171918191919201921192219231924192519261927192819291930193119321933193419351936193719381939194019411942194319441945194619471948194919501951195219531954195519561957195819591960196119621963196419651966196719681969197019711972197319741975197619771978197919801981198219831984198519861987198819891990199119921993199419951996199719981999200020012002200320042005200620072008200920102011201220132014201520162017201820192020202120222023202420252026202720282029203020312032203320342035203620372038203920402041204220432044204520462047204820492050205120522053205420552056205720582059206020612062206320642065206620672068206920702071207220732074207520762077207820792080208120822083208420852086208720882089209020912092209320942095209620972098209921002101210221032104210521062107210821092110211121122113211421152116211721182119212021212122212321242125212621272128212921302131213221332134213521362137213821392140214121422143214421452146214721482149215021512152215321542155215621572158215921602161216221632164216521662167216821692170217121722173217421752176217721782179218021812182218321842185218621872188218921902191219221932194219521962197219821992200220122022203220422052206220722082209221022112212221322142215221622172218221922202221222222232224222522262227222822292230223122322233223422352236223722382239224022412242224322442245224622472248224922502251225222532254225522562257225822592260226122622263226422652266226722682269227022712272227322742275227622772278227922802281228222832284228522862287228822892290229122922293229422952296229722982299230023012302230323042305230623072308230923102311231223132314231523162317231823192320232123222323232423252326232723282329233023312332233323342335233623372338233923402341234223432344234523462347234823492350235123522353235423552356235723582359236023612362236323642365236623672368236923702371237223732374237523762377237823792380238123822383238423852386238723882389239023912392239323942395239623972398239924002401240224032404240524062407240824092410241124122413241424152416241724182419242024212422242324242425242624272428242924302431243224332434243524362437243824392440244124422443244424452446244724482449245024512452245324542455245624572458245924602461246224632464246524662467246824692470247124722473247424752476247724782479248024812482248324842485248624872488248924902491249224932494249524962497249824992500250125022503250425052506250725082509251025112512251325142515251625172518251925202521252225232524252525262527252825292530253125322533253425352536253725382539254025412542254325442545254625472548254925502551255225532554255525562557255825592560256125622563256425652566256725682569257025712572257325742575257625772578257925802581258225832584258525862587258825892590259125922593259425952596259725982599260026012602260326042605260626072608260926102611261226132614261526162617261826192620262126222623262426252626262726282629263026312632263326342635263626372638263926402641264226432644264526462647264826492650265126522653265426552656265726582659266026612662266326642665266626672668266926702671267226732674267526762677267826792680268126822683268426852686268726882689269026912692269326942695269626972698269927002701270227032704270527062707270827092710271127122713271427152716271727182719272027212722272327242725272627272728272927302731273227332734273527362737273827392740274127422743274427452746274727482749275027512752275327542755275627572758275927602761276227632764276527662767276827692770277127722773277427752776277727782779278027812782278327842785278627872788278927902791279227932794279527962797279827992800280128022803280428052806280728082809281028112812281328142815281628172818281928202821282228232824282528262827282828292830283128322833283428352836283728382839284028412842284328442845284628472848284928502851285228532854285528562857285828592860286128622863286428652866286728682869287028712872287328742875287628772878287928802881288228832884288528862887288828892890289128922893289428952896289728982899290029012902290329042905290629072908290929102911291229132914291529162917291829192920292129222923292429252926292729282929293029312932293329342935293629372938293929402941294229432944294529462947294829492950295129522953295429552956295729582959296029612962296329642965296629672968296929702971297229732974297529762977297829792980298129822983298429852986298729882989299029912992299329942995299629972998299930003001300230033004300530063007300830093010301130123013301430153016301730183019302030213022302330243025302630273028302930303031303230333034303530363037303830393040304130423043304430453046304730483049305030513052305330543055305630573058305930603061306230633064306530663067306830693070307130723073307430753076307730783079308030813082308330843085308630873088308930903091309230933094309530963097309830993100310131023103310431053106310731083109311031113112311331143115311631173118311931203121312231233124312531263127312831293130313131323133313431353136313731383139314031413142314331443145314631473148314931503151315231533154315531563157315831593160316131623163316431653166316731683169317031713172317331743175317631773178317931803181318231833184318531863187318831893190319131923193319431953196319731983199320032013202320332043205320632073208320932103211321232133214321532163217321832193220322132223223322432253226322732283229323032313232323332343235323632373238323932403241324232433244324532463247324832493250325132523253325432553256325732583259326032613262326332643265326632673268326932703271327232733274327532763277327832793280328132823283328432853286328732883289329032913292329332943295329632973298329933003301330233033304330533063307330833093310331133123313331433153316331733183319332033213322332333243325332633273328332933303331333233333334333533363337333833393340334133423343334433453346334733483349335033513352335333543355335633573358335933603361336233633364336533663367336833693370337133723373337433753376337733783379338033813382338333843385338633873388338933903391339233933394339533963397339833993400340134023403340434053406340734083409341034113412341334143415341634173418341934203421342234233424342534263427342834293430343134323433343434353436343734383439344034413442344334443445344634473448344934503451345234533454345534563457345834593460346134623463346434653466346734683469347034713472347334743475347634773478347934803481348234833484348534863487348834893490349134923493349434953496349734983499350035013502350335043505350635073508350935103511351235133514351535163517351835193520352135223523352435253526352735283529353035313532353335343535353635373538353935403541354235433544354535463547354835493550355135523553355435553556355735583559356035613562356335643565356635673568356935703571357235733574357535763577357835793580358135823583358435853586358735883589359035913592359335943595359635973598359936003601360236033604360536063607360836093610361136123613361436153616361736183619362036213622362336243625362636273628362936303631363236333634363536363637363836393640364136423643364436453646364736483649365036513652365336543655365636573658365936603661366236633664366536663667366836693670367136723673367436753676367736783679368036813682368336843685368636873688368936903691369236933694369536963697369836993700370137023703370437053706370737083709371037113712371337143715371637173718371937203721372237233724372537263727372837293730373137323733373437353736373737383739374037413742374337443745374637473748374937503751375237533754375537563757375837593760376137623763376437653766376737683769377037713772377337743775377637773778377937803781378237833784378537863787378837893790379137923793379437953796379737983799380038013802380338043805380638073808380938103811381238133814381538163817381838193820382138223823382438253826382738283829383038313832383338343835383638373838383938403841384238433844384538463847384838493850385138523853385438553856385738583859386038613862386338643865386638673868386938703871387238733874387538763877387838793880388138823883388438853886388738883889389038913892389338943895389638973898389939003901390239033904390539063907390839093910391139123913391439153916391739183919392039213922392339243925392639273928392939303931393239333934393539363937393839393940394139423943394439453946394739483949395039513952395339543955395639573958395939603961396239633964396539663967396839693970397139723973397439753976397739783979398039813982398339843985398639873988398939903991399239933994399539963997399839994000400140024003400440054006400740084009401040114012401340144015401640174018
  1. #
  2. # (C) Copyright 2000 - 2008
  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. - board Board dependent files
  107. - common Misc architecture independent functions
  108. - cpu CPU specific files
  109. - 74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
  110. - arm720t Files specific to ARM 720 CPUs
  111. - arm920t Files specific to ARM 920 CPUs
  112. - at91rm9200 Files specific to Atmel AT91RM9200 CPU
  113. - imx Files specific to Freescale MC9328 i.MX CPUs
  114. - s3c24x0 Files specific to Samsung S3C24X0 CPUs
  115. - arm925t Files specific to ARM 925 CPUs
  116. - arm926ejs Files specific to ARM 926 CPUs
  117. - arm1136 Files specific to ARM 1136 CPUs
  118. - at32ap Files specific to Atmel AVR32 AP CPUs
  119. - i386 Files specific to i386 CPUs
  120. - ixp Files specific to Intel XScale IXP CPUs
  121. - leon2 Files specific to Gaisler LEON2 SPARC CPU
  122. - leon3 Files specific to Gaisler LEON3 SPARC CPU
  123. - mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
  124. - mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
  125. - mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
  126. - mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
  127. - mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
  128. - mips Files specific to MIPS CPUs
  129. - mpc5xx Files specific to Freescale MPC5xx CPUs
  130. - mpc5xxx Files specific to Freescale MPC5xxx CPUs
  131. - mpc8xx Files specific to Freescale MPC8xx CPUs
  132. - mpc8220 Files specific to Freescale MPC8220 CPUs
  133. - mpc824x Files specific to Freescale MPC824x CPUs
  134. - mpc8260 Files specific to Freescale MPC8260 CPUs
  135. - mpc85xx Files specific to Freescale MPC85xx CPUs
  136. - nios Files specific to Altera NIOS CPUs
  137. - nios2 Files specific to Altera Nios-II CPUs
  138. - ppc4xx Files specific to AMCC PowerPC 4xx CPUs
  139. - pxa Files specific to Intel XScale PXA CPUs
  140. - s3c44b0 Files specific to Samsung S3C44B0 CPUs
  141. - sa1100 Files specific to Intel StrongARM SA1100 CPUs
  142. - disk Code for disk drive partition handling
  143. - doc Documentation (don't expect too much)
  144. - drivers Commonly used device drivers
  145. - dtt Digital Thermometer and Thermostat drivers
  146. - examples Example code for standalone applications, etc.
  147. - include Header Files
  148. - lib_arm Files generic to ARM architecture
  149. - lib_avr32 Files generic to AVR32 architecture
  150. - lib_generic Files generic to all architectures
  151. - lib_i386 Files generic to i386 architecture
  152. - lib_m68k Files generic to m68k architecture
  153. - lib_mips Files generic to MIPS architecture
  154. - lib_nios Files generic to NIOS architecture
  155. - lib_ppc Files generic to PowerPC architecture
  156. - lib_sparc Files generic to SPARC architecture
  157. - libfdt Library files to support flattened device trees
  158. - net Networking code
  159. - post Power On Self Test
  160. - rtc Real Time Clock drivers
  161. - tools Tools to build S-Record or U-Boot images, etc.
  162. Software Configuration:
  163. =======================
  164. Configuration is usually done using C preprocessor defines; the
  165. rationale behind that is to avoid dead code whenever possible.
  166. There are two classes of configuration variables:
  167. * Configuration _OPTIONS_:
  168. These are selectable by the user and have names beginning with
  169. "CONFIG_".
  170. * Configuration _SETTINGS_:
  171. These depend on the hardware etc. and should not be meddled with if
  172. you don't know what you're doing; they have names beginning with
  173. "CFG_".
  174. Later we will add a configuration tool - probably similar to or even
  175. identical to what's used for the Linux kernel. Right now, we have to
  176. do the configuration by hand, which means creating some symbolic
  177. links and editing some configuration files. We use the TQM8xxL boards
  178. as an example here.
  179. Selection of Processor Architecture and Board Type:
  180. ---------------------------------------------------
  181. For all supported boards there are ready-to-use default
  182. configurations available; just type "make <board_name>_config".
  183. Example: For a TQM823L module type:
  184. cd u-boot
  185. make TQM823L_config
  186. For the Cogent platform, you need to specify the CPU type as well;
  187. e.g. "make cogent_mpc8xx_config". And also configure the cogent
  188. directory according to the instructions in cogent/README.
  189. Configuration Options:
  190. ----------------------
  191. Configuration depends on the combination of board and CPU type; all
  192. such information is kept in a configuration file
  193. "include/configs/<board_name>.h".
  194. Example: For a TQM823L module, all configuration settings are in
  195. "include/configs/TQM823L.h".
  196. Many of the options are named exactly as the corresponding Linux
  197. kernel configuration options. The intention is to make it easier to
  198. build a config tool - later.
  199. The following options need to be configured:
  200. - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
  201. - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
  202. - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
  203. Define exactly one, e.g. CONFIG_ATSTK1002
  204. - CPU Module Type: (if CONFIG_COGENT is defined)
  205. Define exactly one of
  206. CONFIG_CMA286_60_OLD
  207. --- FIXME --- not tested yet:
  208. CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
  209. CONFIG_CMA287_23, CONFIG_CMA287_50
  210. - Motherboard Type: (if CONFIG_COGENT is defined)
  211. Define exactly one of
  212. CONFIG_CMA101, CONFIG_CMA102
  213. - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
  214. Define one or more of
  215. CONFIG_CMA302
  216. - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
  217. Define one or more of
  218. CONFIG_LCD_HEARTBEAT - update a character position on
  219. the LCD display every second with
  220. a "rotator" |\-/|\-/
  221. - Board flavour: (if CONFIG_MPC8260ADS is defined)
  222. CONFIG_ADSTYPE
  223. Possible values are:
  224. CFG_8260ADS - original MPC8260ADS
  225. CFG_8266ADS - MPC8266ADS
  226. CFG_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
  227. CFG_8272ADS - MPC8272ADS
  228. - MPC824X Family Member (if CONFIG_MPC824X is defined)
  229. Define exactly one of
  230. CONFIG_MPC8240, CONFIG_MPC8245
  231. - 8xx CPU Options: (if using an MPC8xx CPU)
  232. CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
  233. get_gclk_freq() cannot work
  234. e.g. if there is no 32KHz
  235. reference PIT/RTC clock
  236. CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
  237. or XTAL/EXTAL)
  238. - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
  239. CFG_8xx_CPUCLK_MIN
  240. CFG_8xx_CPUCLK_MAX
  241. CONFIG_8xx_CPUCLK_DEFAULT
  242. See doc/README.MPC866
  243. CFG_MEASURE_CPUCLK
  244. Define this to measure the actual CPU clock instead
  245. of relying on the correctness of the configured
  246. values. Mostly useful for board bringup to make sure
  247. the PLL is locked at the intended frequency. Note
  248. that this requires a (stable) reference clock (32 kHz
  249. RTC clock or CFG_8XX_XIN)
  250. - Intel Monahans options:
  251. CFG_MONAHANS_RUN_MODE_OSC_RATIO
  252. Defines the Monahans run mode to oscillator
  253. ratio. Valid values are 8, 16, 24, 31. The core
  254. frequency is this value multiplied by 13 MHz.
  255. CFG_MONAHANS_TURBO_RUN_MODE_RATIO
  256. Defines the Monahans turbo mode to oscillator
  257. ratio. Valid values are 1 (default if undefined) and
  258. 2. The core frequency as calculated above is multiplied
  259. by this value.
  260. - Linux Kernel Interface:
  261. CONFIG_CLOCKS_IN_MHZ
  262. U-Boot stores all clock information in Hz
  263. internally. For binary compatibility with older Linux
  264. kernels (which expect the clocks passed in the
  265. bd_info data to be in MHz) the environment variable
  266. "clocks_in_mhz" can be defined so that U-Boot
  267. converts clock data to MHZ before passing it to the
  268. Linux kernel.
  269. When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
  270. "clocks_in_mhz=1" is automatically included in the
  271. default environment.
  272. CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
  273. When transferring memsize parameter to linux, some versions
  274. expect it to be in bytes, others in MB.
  275. Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
  276. CONFIG_OF_LIBFDT
  277. New kernel versions are expecting firmware settings to be
  278. passed using flattened device trees (based on open firmware
  279. concepts).
  280. CONFIG_OF_LIBFDT
  281. * New libfdt-based support
  282. * Adds the "fdt" command
  283. * The bootm command automatically updates the fdt
  284. OF_CPU - The proper name of the cpus node.
  285. OF_SOC - The proper name of the soc node.
  286. OF_TBCLK - The timebase frequency.
  287. OF_STDOUT_PATH - The path to the console device
  288. boards with QUICC Engines require OF_QE to set UCC MAC
  289. addresses
  290. CONFIG_OF_BOARD_SETUP
  291. Board code has addition modification that it wants to make
  292. to the flat device tree before handing it off to the kernel
  293. CONFIG_OF_BOOT_CPU
  294. This define fills in the correct boot CPU in the boot
  295. param header, the default value is zero if undefined.
  296. - Serial Ports:
  297. CONFIG_PL010_SERIAL
  298. Define this if you want support for Amba PrimeCell PL010 UARTs.
  299. CONFIG_PL011_SERIAL
  300. Define this if you want support for Amba PrimeCell PL011 UARTs.
  301. CONFIG_PL011_CLOCK
  302. If you have Amba PrimeCell PL011 UARTs, set this variable to
  303. the clock speed of the UARTs.
  304. CONFIG_PL01x_PORTS
  305. If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
  306. define this to a list of base addresses for each (supported)
  307. port. See e.g. include/configs/versatile.h
  308. - Console Interface:
  309. Depending on board, define exactly one serial port
  310. (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
  311. CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
  312. console by defining CONFIG_8xx_CONS_NONE
  313. Note: if CONFIG_8xx_CONS_NONE is defined, the serial
  314. port routines must be defined elsewhere
  315. (i.e. serial_init(), serial_getc(), ...)
  316. CONFIG_CFB_CONSOLE
  317. Enables console device for a color framebuffer. Needs following
  318. defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
  319. VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
  320. (default big endian)
  321. VIDEO_HW_RECTFILL graphic chip supports
  322. rectangle fill
  323. (cf. smiLynxEM)
  324. VIDEO_HW_BITBLT graphic chip supports
  325. bit-blit (cf. smiLynxEM)
  326. VIDEO_VISIBLE_COLS visible pixel columns
  327. (cols=pitch)
  328. VIDEO_VISIBLE_ROWS visible pixel rows
  329. VIDEO_PIXEL_SIZE bytes per pixel
  330. VIDEO_DATA_FORMAT graphic data format
  331. (0-5, cf. cfb_console.c)
  332. VIDEO_FB_ADRS framebuffer address
  333. VIDEO_KBD_INIT_FCT keyboard int fct
  334. (i.e. i8042_kbd_init())
  335. VIDEO_TSTC_FCT test char fct
  336. (i.e. i8042_tstc)
  337. VIDEO_GETC_FCT get char fct
  338. (i.e. i8042_getc)
  339. CONFIG_CONSOLE_CURSOR cursor drawing on/off
  340. (requires blink timer
  341. cf. i8042.c)
  342. CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
  343. CONFIG_CONSOLE_TIME display time/date info in
  344. upper right corner
  345. (requires CONFIG_CMD_DATE)
  346. CONFIG_VIDEO_LOGO display Linux logo in
  347. upper left corner
  348. CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
  349. linux_logo.h for logo.
  350. Requires CONFIG_VIDEO_LOGO
  351. CONFIG_CONSOLE_EXTRA_INFO
  352. additional board info beside
  353. the logo
  354. When CONFIG_CFB_CONSOLE is defined, video console is
  355. default i/o. Serial console can be forced with
  356. environment 'console=serial'.
  357. When CONFIG_SILENT_CONSOLE is defined, all console
  358. messages (by U-Boot and Linux!) can be silenced with
  359. the "silent" environment variable. See
  360. doc/README.silent for more information.
  361. - Console Baudrate:
  362. CONFIG_BAUDRATE - in bps
  363. Select one of the baudrates listed in
  364. CFG_BAUDRATE_TABLE, see below.
  365. CFG_BRGCLK_PRESCALE, baudrate prescale
  366. - Interrupt driven serial port input:
  367. CONFIG_SERIAL_SOFTWARE_FIFO
  368. PPC405GP only.
  369. Use an interrupt handler for receiving data on the
  370. serial port. It also enables using hardware handshake
  371. (RTS/CTS) and UART's built-in FIFO. Set the number of
  372. bytes the interrupt driven input buffer should have.
  373. Leave undefined to disable this feature, including
  374. disable the buffer and hardware handshake.
  375. - Console UART Number:
  376. CONFIG_UART1_CONSOLE
  377. AMCC PPC4xx only.
  378. If defined internal UART1 (and not UART0) is used
  379. as default U-Boot console.
  380. - Boot Delay: CONFIG_BOOTDELAY - in seconds
  381. Delay before automatically booting the default image;
  382. set to -1 to disable autoboot.
  383. See doc/README.autoboot for these options that
  384. work with CONFIG_BOOTDELAY. None are required.
  385. CONFIG_BOOT_RETRY_TIME
  386. CONFIG_BOOT_RETRY_MIN
  387. CONFIG_AUTOBOOT_KEYED
  388. CONFIG_AUTOBOOT_PROMPT
  389. CONFIG_AUTOBOOT_DELAY_STR
  390. CONFIG_AUTOBOOT_STOP_STR
  391. CONFIG_AUTOBOOT_DELAY_STR2
  392. CONFIG_AUTOBOOT_STOP_STR2
  393. CONFIG_ZERO_BOOTDELAY_CHECK
  394. CONFIG_RESET_TO_RETRY
  395. - Autoboot Command:
  396. CONFIG_BOOTCOMMAND
  397. Only needed when CONFIG_BOOTDELAY is enabled;
  398. define a command string that is automatically executed
  399. when no character is read on the console interface
  400. within "Boot Delay" after reset.
  401. CONFIG_BOOTARGS
  402. This can be used to pass arguments to the bootm
  403. command. The value of CONFIG_BOOTARGS goes into the
  404. environment value "bootargs".
  405. CONFIG_RAMBOOT and CONFIG_NFSBOOT
  406. The value of these goes into the environment as
  407. "ramboot" and "nfsboot" respectively, and can be used
  408. as a convenience, when switching between booting from
  409. RAM and NFS.
  410. - Pre-Boot Commands:
  411. CONFIG_PREBOOT
  412. When this option is #defined, the existence of the
  413. environment variable "preboot" will be checked
  414. immediately before starting the CONFIG_BOOTDELAY
  415. countdown and/or running the auto-boot command resp.
  416. entering interactive mode.
  417. This feature is especially useful when "preboot" is
  418. automatically generated or modified. For an example
  419. see the LWMON board specific code: here "preboot" is
  420. modified when the user holds down a certain
  421. combination of keys on the (special) keyboard when
  422. booting the systems
  423. - Serial Download Echo Mode:
  424. CONFIG_LOADS_ECHO
  425. If defined to 1, all characters received during a
  426. serial download (using the "loads" command) are
  427. echoed back. This might be needed by some terminal
  428. emulations (like "cu"), but may as well just take
  429. time on others. This setting #define's the initial
  430. value of the "loads_echo" environment variable.
  431. - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
  432. CONFIG_KGDB_BAUDRATE
  433. Select one of the baudrates listed in
  434. CFG_BAUDRATE_TABLE, see below.
  435. - Monitor Functions:
  436. Monitor commands can be included or excluded
  437. from the build by using the #include files
  438. "config_cmd_all.h" and #undef'ing unwanted
  439. commands, or using "config_cmd_default.h"
  440. and augmenting with additional #define's
  441. for wanted commands.
  442. The default command configuration includes all commands
  443. except those marked below with a "*".
  444. CONFIG_CMD_ASKENV * ask for env variable
  445. CONFIG_CMD_AUTOSCRIPT Autoscript Support
  446. CONFIG_CMD_BDI bdinfo
  447. CONFIG_CMD_BEDBUG * Include BedBug Debugger
  448. CONFIG_CMD_BMP * BMP support
  449. CONFIG_CMD_BSP * Board specific commands
  450. CONFIG_CMD_BOOTD bootd
  451. CONFIG_CMD_CACHE * icache, dcache
  452. CONFIG_CMD_CONSOLE coninfo
  453. CONFIG_CMD_DATE * support for RTC, date/time...
  454. CONFIG_CMD_DHCP * DHCP support
  455. CONFIG_CMD_DIAG * Diagnostics
  456. CONFIG_CMD_DOC * Disk-On-Chip Support
  457. CONFIG_CMD_DTT * Digital Therm and Thermostat
  458. CONFIG_CMD_ECHO echo arguments
  459. CONFIG_CMD_EEPROM * EEPROM read/write support
  460. CONFIG_CMD_ELF * bootelf, bootvx
  461. CONFIG_CMD_ENV saveenv
  462. CONFIG_CMD_FDC * Floppy Disk Support
  463. CONFIG_CMD_FAT * FAT partition support
  464. CONFIG_CMD_FDOS * Dos diskette Support
  465. CONFIG_CMD_FLASH flinfo, erase, protect
  466. CONFIG_CMD_FPGA FPGA device initialization support
  467. CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
  468. CONFIG_CMD_I2C * I2C serial bus support
  469. CONFIG_CMD_IDE * IDE harddisk support
  470. CONFIG_CMD_IMI iminfo
  471. CONFIG_CMD_IMLS List all found images
  472. CONFIG_CMD_IMMAP * IMMR dump support
  473. CONFIG_CMD_IRQ * irqinfo
  474. CONFIG_CMD_ITEST Integer/string test of 2 values
  475. CONFIG_CMD_JFFS2 * JFFS2 Support
  476. CONFIG_CMD_KGDB * kgdb
  477. CONFIG_CMD_LOADB loadb
  478. CONFIG_CMD_LOADS loads
  479. CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
  480. loop, loopw, mtest
  481. CONFIG_CMD_MISC Misc functions like sleep etc
  482. CONFIG_CMD_MMC * MMC memory mapped support
  483. CONFIG_CMD_MII * MII utility commands
  484. CONFIG_CMD_NAND * NAND support
  485. CONFIG_CMD_NET bootp, tftpboot, rarpboot
  486. CONFIG_CMD_PCI * pciinfo
  487. CONFIG_CMD_PCMCIA * PCMCIA support
  488. CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
  489. host
  490. CONFIG_CMD_PORTIO * Port I/O
  491. CONFIG_CMD_REGINFO * Register dump
  492. CONFIG_CMD_RUN run command in env variable
  493. CONFIG_CMD_SAVES * save S record dump
  494. CONFIG_CMD_SCSI * SCSI Support
  495. CONFIG_CMD_SDRAM * print SDRAM configuration information
  496. (requires CONFIG_CMD_I2C)
  497. CONFIG_CMD_SETGETDCR Support for DCR Register access
  498. (4xx only)
  499. CONFIG_CMD_SPI * SPI serial bus support
  500. CONFIG_CMD_USB * USB support
  501. CONFIG_CMD_VFD * VFD support (TRAB)
  502. CONFIG_CMD_CDP * Cisco Discover Protocol support
  503. CONFIG_CMD_FSL * Microblaze FSL support
  504. EXAMPLE: If you want all functions except of network
  505. support you can write:
  506. #include "config_cmd_all.h"
  507. #undef CONFIG_CMD_NET
  508. Other Commands:
  509. fdt (flattened device tree) command: CONFIG_OF_LIBFDT
  510. Note: Don't enable the "icache" and "dcache" commands
  511. (configuration option CONFIG_CMD_CACHE) unless you know
  512. what you (and your U-Boot users) are doing. Data
  513. cache cannot be enabled on systems like the 8xx or
  514. 8260 (where accesses to the IMMR region must be
  515. uncached), and it cannot be disabled on all other
  516. systems where we (mis-) use the data cache to hold an
  517. initial stack and some data.
  518. XXX - this list needs to get updated!
  519. - Watchdog:
  520. CONFIG_WATCHDOG
  521. If this variable is defined, it enables watchdog
  522. support. There must be support in the platform specific
  523. code for a watchdog. For the 8xx and 8260 CPUs, the
  524. SIU Watchdog feature is enabled in the SYPCR
  525. register.
  526. - U-Boot Version:
  527. CONFIG_VERSION_VARIABLE
  528. If this variable is defined, an environment variable
  529. named "ver" is created by U-Boot showing the U-Boot
  530. version as printed by the "version" command.
  531. This variable is readonly.
  532. - Real-Time Clock:
  533. When CONFIG_CMD_DATE is selected, the type of the RTC
  534. has to be selected, too. Define exactly one of the
  535. following options:
  536. CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
  537. CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
  538. CONFIG_RTC_MC13783 - use MC13783 RTC
  539. CONFIG_RTC_MC146818 - use MC146818 RTC
  540. CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
  541. CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
  542. CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
  543. CONFIG_RTC_DS164x - use Dallas DS164x RTC
  544. CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
  545. CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
  546. CFG_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
  547. Note that if the RTC uses I2C, then the I2C interface
  548. must also be configured. See I2C Support, below.
  549. - Timestamp Support:
  550. When CONFIG_TIMESTAMP is selected, the timestamp
  551. (date and time) of an image is printed by image
  552. commands like bootm or iminfo. This option is
  553. automatically enabled when you select CONFIG_CMD_DATE .
  554. - Partition Support:
  555. CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
  556. and/or CONFIG_ISO_PARTITION
  557. If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
  558. CONFIG_CMD_SCSI) you must configure support for at
  559. least one partition type as well.
  560. - IDE Reset method:
  561. CONFIG_IDE_RESET_ROUTINE - this is defined in several
  562. board configurations files but used nowhere!
  563. CONFIG_IDE_RESET - is this is defined, IDE Reset will
  564. be performed by calling the function
  565. ide_set_reset(int reset)
  566. which has to be defined in a board specific file
  567. - ATAPI Support:
  568. CONFIG_ATAPI
  569. Set this to enable ATAPI support.
  570. - LBA48 Support
  571. CONFIG_LBA48
  572. Set this to enable support for disks larger than 137GB
  573. Also look at CFG_64BIT_LBA ,CFG_64BIT_VSPRINTF and CFG_64BIT_STRTOUL
  574. Whithout these , LBA48 support uses 32bit variables and will 'only'
  575. support disks up to 2.1TB.
  576. CFG_64BIT_LBA:
  577. When enabled, makes the IDE subsystem use 64bit sector addresses.
  578. Default is 32bit.
  579. - SCSI Support:
  580. At the moment only there is only support for the
  581. SYM53C8XX SCSI controller; define
  582. CONFIG_SCSI_SYM53C8XX to enable it.
  583. CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and
  584. CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID *
  585. CFG_SCSI_MAX_LUN] can be adjusted to define the
  586. maximum numbers of LUNs, SCSI ID's and target
  587. devices.
  588. CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
  589. - NETWORK Support (PCI):
  590. CONFIG_E1000
  591. Support for Intel 8254x gigabit chips.
  592. CONFIG_E1000_FALLBACK_MAC
  593. default MAC for empty EEPROM after production.
  594. CONFIG_EEPRO100
  595. Support for Intel 82557/82559/82559ER chips.
  596. Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
  597. write routine for first time initialisation.
  598. CONFIG_TULIP
  599. Support for Digital 2114x chips.
  600. Optional CONFIG_TULIP_SELECT_MEDIA for board specific
  601. modem chip initialisation (KS8761/QS6611).
  602. CONFIG_NATSEMI
  603. Support for National dp83815 chips.
  604. CONFIG_NS8382X
  605. Support for National dp8382[01] gigabit chips.
  606. - NETWORK Support (other):
  607. CONFIG_DRIVER_LAN91C96
  608. Support for SMSC's LAN91C96 chips.
  609. CONFIG_LAN91C96_BASE
  610. Define this to hold the physical address
  611. of the LAN91C96's I/O space
  612. CONFIG_LAN91C96_USE_32_BIT
  613. Define this to enable 32 bit addressing
  614. CONFIG_DRIVER_SMC91111
  615. Support for SMSC's LAN91C111 chip
  616. CONFIG_SMC91111_BASE
  617. Define this to hold the physical address
  618. of the device (I/O space)
  619. CONFIG_SMC_USE_32_BIT
  620. Define this if data bus is 32 bits
  621. CONFIG_SMC_USE_IOFUNCS
  622. Define this to use i/o functions instead of macros
  623. (some hardware wont work with macros)
  624. CONFIG_DRIVER_SMC911X
  625. Support for SMSC's LAN911x and LAN921x chips
  626. CONFIG_DRIVER_SMC911X_BASE
  627. Define this to hold the physical address
  628. of the device (I/O space)
  629. CONFIG_DRIVER_SMC911X_32_BIT
  630. Define this if data bus is 32 bits
  631. CONFIG_DRIVER_SMC911X_16_BIT
  632. Define this if data bus is 16 bits. If your processor
  633. automatically converts one 32 bit word to two 16 bit
  634. words you may also try CONFIG_DRIVER_SMC911X_32_BIT.
  635. - USB Support:
  636. At the moment only the UHCI host controller is
  637. supported (PIP405, MIP405, MPC5200); define
  638. CONFIG_USB_UHCI to enable it.
  639. define CONFIG_USB_KEYBOARD to enable the USB Keyboard
  640. and define CONFIG_USB_STORAGE to enable the USB
  641. storage devices.
  642. Note:
  643. Supported are USB Keyboards and USB Floppy drives
  644. (TEAC FD-05PUB).
  645. MPC5200 USB requires additional defines:
  646. CONFIG_USB_CLOCK
  647. for 528 MHz Clock: 0x0001bbbb
  648. CONFIG_USB_CONFIG
  649. for differential drivers: 0x00001000
  650. for single ended drivers: 0x00005000
  651. CFG_USB_EVENT_POLL
  652. May be defined to allow interrupt polling
  653. instead of using asynchronous interrupts
  654. - USB Device:
  655. Define the below if you wish to use the USB console.
  656. Once firmware is rebuilt from a serial console issue the
  657. command "setenv stdin usbtty; setenv stdout usbtty" and
  658. attach your USB cable. The Unix command "dmesg" should print
  659. it has found a new device. The environment variable usbtty
  660. can be set to gserial or cdc_acm to enable your device to
  661. appear to a USB host as a Linux gserial device or a
  662. Common Device Class Abstract Control Model serial device.
  663. If you select usbtty = gserial you should be able to enumerate
  664. a Linux host by
  665. # modprobe usbserial vendor=0xVendorID product=0xProductID
  666. else if using cdc_acm, simply setting the environment
  667. variable usbtty to be cdc_acm should suffice. The following
  668. might be defined in YourBoardName.h
  669. CONFIG_USB_DEVICE
  670. Define this to build a UDC device
  671. CONFIG_USB_TTY
  672. Define this to have a tty type of device available to
  673. talk to the UDC device
  674. CFG_CONSOLE_IS_IN_ENV
  675. Define this if you want stdin, stdout &/or stderr to
  676. be set to usbtty.
  677. mpc8xx:
  678. CFG_USB_EXTC_CLK 0xBLAH
  679. Derive USB clock from external clock "blah"
  680. - CFG_USB_EXTC_CLK 0x02
  681. CFG_USB_BRG_CLK 0xBLAH
  682. Derive USB clock from brgclk
  683. - CFG_USB_BRG_CLK 0x04
  684. If you have a USB-IF assigned VendorID then you may wish to
  685. define your own vendor specific values either in BoardName.h
  686. or directly in usbd_vendor_info.h. If you don't define
  687. CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
  688. CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
  689. should pretend to be a Linux device to it's target host.
  690. CONFIG_USBD_MANUFACTURER
  691. Define this string as the name of your company for
  692. - CONFIG_USBD_MANUFACTURER "my company"
  693. CONFIG_USBD_PRODUCT_NAME
  694. Define this string as the name of your product
  695. - CONFIG_USBD_PRODUCT_NAME "acme usb device"
  696. CONFIG_USBD_VENDORID
  697. Define this as your assigned Vendor ID from the USB
  698. Implementors Forum. This *must* be a genuine Vendor ID
  699. to avoid polluting the USB namespace.
  700. - CONFIG_USBD_VENDORID 0xFFFF
  701. CONFIG_USBD_PRODUCTID
  702. Define this as the unique Product ID
  703. for your device
  704. - CONFIG_USBD_PRODUCTID 0xFFFF
  705. - MMC Support:
  706. The MMC controller on the Intel PXA is supported. To
  707. enable this define CONFIG_MMC. The MMC can be
  708. accessed from the boot prompt by mapping the device
  709. to physical memory similar to flash. Command line is
  710. enabled with CONFIG_CMD_MMC. The MMC driver also works with
  711. the FAT fs. This is enabled with CONFIG_CMD_FAT.
  712. - Journaling Flash filesystem support:
  713. CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
  714. CONFIG_JFFS2_NAND_DEV
  715. Define these for a default partition on a NAND device
  716. CFG_JFFS2_FIRST_SECTOR,
  717. CFG_JFFS2_FIRST_BANK, CFG_JFFS2_NUM_BANKS
  718. Define these for a default partition on a NOR device
  719. CFG_JFFS_CUSTOM_PART
  720. Define this to create an own partition. You have to provide a
  721. function struct part_info* jffs2_part_info(int part_num)
  722. If you define only one JFFS2 partition you may also want to
  723. #define CFG_JFFS_SINGLE_PART 1
  724. to disable the command chpart. This is the default when you
  725. have not defined a custom partition
  726. - Keyboard Support:
  727. CONFIG_ISA_KEYBOARD
  728. Define this to enable standard (PC-Style) keyboard
  729. support
  730. CONFIG_I8042_KBD
  731. Standard PC keyboard driver with US (is default) and
  732. GERMAN key layout (switch via environment 'keymap=de') support.
  733. Export function i8042_kbd_init, i8042_tstc and i8042_getc
  734. for cfb_console. Supports cursor blinking.
  735. - Video support:
  736. CONFIG_VIDEO
  737. Define this to enable video support (for output to
  738. video).
  739. CONFIG_VIDEO_CT69000
  740. Enable Chips & Technologies 69000 Video chip
  741. CONFIG_VIDEO_SMI_LYNXEM
  742. Enable Silicon Motion SMI 712/710/810 Video chip. The
  743. video output is selected via environment 'videoout'
  744. (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
  745. assumed.
  746. For the CT69000 and SMI_LYNXEM drivers, videomode is
  747. selected via environment 'videomode'. Two different ways
  748. are possible:
  749. - "videomode=num" 'num' is a standard LiLo mode numbers.
  750. Following standard modes are supported (* is default):
  751. Colors 640x480 800x600 1024x768 1152x864 1280x1024
  752. -------------+---------------------------------------------
  753. 8 bits | 0x301* 0x303 0x305 0x161 0x307
  754. 15 bits | 0x310 0x313 0x316 0x162 0x319
  755. 16 bits | 0x311 0x314 0x317 0x163 0x31A
  756. 24 bits | 0x312 0x315 0x318 ? 0x31B
  757. -------------+---------------------------------------------
  758. (i.e. setenv videomode 317; saveenv; reset;)
  759. - "videomode=bootargs" all the video parameters are parsed
  760. from the bootargs. (See drivers/video/videomodes.c)
  761. CONFIG_VIDEO_SED13806
  762. Enable Epson SED13806 driver. This driver supports 8bpp
  763. and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
  764. or CONFIG_VIDEO_SED13806_16BPP
  765. - Keyboard Support:
  766. CONFIG_KEYBOARD
  767. Define this to enable a custom keyboard support.
  768. This simply calls drv_keyboard_init() which must be
  769. defined in your board-specific files.
  770. The only board using this so far is RBC823.
  771. - LCD Support: CONFIG_LCD
  772. Define this to enable LCD support (for output to LCD
  773. display); also select one of the supported displays
  774. by defining one of these:
  775. CONFIG_ATMEL_LCD:
  776. HITACHI TX09D70VM1CCA, 3.5", 240x320.
  777. CONFIG_NEC_NL6448AC33:
  778. NEC NL6448AC33-18. Active, color, single scan.
  779. CONFIG_NEC_NL6448BC20
  780. NEC NL6448BC20-08. 6.5", 640x480.
  781. Active, color, single scan.
  782. CONFIG_NEC_NL6448BC33_54
  783. NEC NL6448BC33-54. 10.4", 640x480.
  784. Active, color, single scan.
  785. CONFIG_SHARP_16x9
  786. Sharp 320x240. Active, color, single scan.
  787. It isn't 16x9, and I am not sure what it is.
  788. CONFIG_SHARP_LQ64D341
  789. Sharp LQ64D341 display, 640x480.
  790. Active, color, single scan.
  791. CONFIG_HLD1045
  792. HLD1045 display, 640x480.
  793. Active, color, single scan.
  794. CONFIG_OPTREX_BW
  795. Optrex CBL50840-2 NF-FW 99 22 M5
  796. or
  797. Hitachi LMG6912RPFC-00T
  798. or
  799. Hitachi SP14Q002
  800. 320x240. Black & white.
  801. Normally display is black on white background; define
  802. CFG_WHITE_ON_BLACK to get it inverted.
  803. - Splash Screen Support: CONFIG_SPLASH_SCREEN
  804. If this option is set, the environment is checked for
  805. a variable "splashimage". If found, the usual display
  806. of logo, copyright and system information on the LCD
  807. is suppressed and the BMP image at the address
  808. specified in "splashimage" is loaded instead. The
  809. console is redirected to the "nulldev", too. This
  810. allows for a "silent" boot where a splash screen is
  811. loaded very quickly after power-on.
  812. - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
  813. If this option is set, additionally to standard BMP
  814. images, gzipped BMP images can be displayed via the
  815. splashscreen support or the bmp command.
  816. - Compression support:
  817. CONFIG_BZIP2
  818. If this option is set, support for bzip2 compressed
  819. images is included. If not, only uncompressed and gzip
  820. compressed images are supported.
  821. NOTE: the bzip2 algorithm requires a lot of RAM, so
  822. the malloc area (as defined by CFG_MALLOC_LEN) should
  823. be at least 4MB.
  824. CONFIG_LZMA
  825. If this option is set, support for lzma compressed
  826. images is included.
  827. Note: The LZMA algorithm adds between 2 and 4KB of code and it
  828. requires an amount of dynamic memory that is given by the
  829. formula:
  830. (1846 + 768 << (lc + lp)) * sizeof(uint16)
  831. Where lc and lp stand for, respectively, Literal context bits
  832. and Literal pos bits.
  833. This value is upper-bounded by 14MB in the worst case. Anyway,
  834. for a ~4MB large kernel image, we have lc=3 and lp=0 for a
  835. total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
  836. a very small buffer.
  837. Use the lzmainfo tool to determinate the lc and lp values and
  838. then calculate the amount of needed dynamic memory (ensuring
  839. the appropriate CFG_MALLOC_LEN value).
  840. - MII/PHY support:
  841. CONFIG_PHY_ADDR
  842. The address of PHY on MII bus.
  843. CONFIG_PHY_CLOCK_FREQ (ppc4xx)
  844. The clock frequency of the MII bus
  845. CONFIG_PHY_GIGE
  846. If this option is set, support for speed/duplex
  847. detection of gigabit PHY is included.
  848. CONFIG_PHY_RESET_DELAY
  849. Some PHY like Intel LXT971A need extra delay after
  850. reset before any MII register access is possible.
  851. For such PHY, set this option to the usec delay
  852. required. (minimum 300usec for LXT971A)
  853. CONFIG_PHY_CMD_DELAY (ppc4xx)
  854. Some PHY like Intel LXT971A need extra delay after
  855. command issued before MII status register can be read
  856. - Ethernet address:
  857. CONFIG_ETHADDR
  858. CONFIG_ETH1ADDR
  859. CONFIG_ETH2ADDR
  860. CONFIG_ETH3ADDR
  861. CONFIG_ETH4ADDR
  862. CONFIG_ETH5ADDR
  863. Define a default value for Ethernet address to use
  864. for the respective Ethernet interface, in case this
  865. is not determined automatically.
  866. - IP address:
  867. CONFIG_IPADDR
  868. Define a default value for the IP address to use for
  869. the default Ethernet interface, in case this is not
  870. determined through e.g. bootp.
  871. - Server IP address:
  872. CONFIG_SERVERIP
  873. Defines a default value for the IP address of a TFTP
  874. server to contact when using the "tftboot" command.
  875. - Multicast TFTP Mode:
  876. CONFIG_MCAST_TFTP
  877. Defines whether you want to support multicast TFTP as per
  878. rfc-2090; for example to work with atftp. Lets lots of targets
  879. tftp down the same boot image concurrently. Note: the Ethernet
  880. driver in use must provide a function: mcast() to join/leave a
  881. multicast group.
  882. CONFIG_BOOTP_RANDOM_DELAY
  883. - BOOTP Recovery Mode:
  884. CONFIG_BOOTP_RANDOM_DELAY
  885. If you have many targets in a network that try to
  886. boot using BOOTP, you may want to avoid that all
  887. systems send out BOOTP requests at precisely the same
  888. moment (which would happen for instance at recovery
  889. from a power failure, when all systems will try to
  890. boot, thus flooding the BOOTP server. Defining
  891. CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
  892. inserted before sending out BOOTP requests. The
  893. following delays are inserted then:
  894. 1st BOOTP request: delay 0 ... 1 sec
  895. 2nd BOOTP request: delay 0 ... 2 sec
  896. 3rd BOOTP request: delay 0 ... 4 sec
  897. 4th and following
  898. BOOTP requests: delay 0 ... 8 sec
  899. - DHCP Advanced Options:
  900. You can fine tune the DHCP functionality by defining
  901. CONFIG_BOOTP_* symbols:
  902. CONFIG_BOOTP_SUBNETMASK
  903. CONFIG_BOOTP_GATEWAY
  904. CONFIG_BOOTP_HOSTNAME
  905. CONFIG_BOOTP_NISDOMAIN
  906. CONFIG_BOOTP_BOOTPATH
  907. CONFIG_BOOTP_BOOTFILESIZE
  908. CONFIG_BOOTP_DNS
  909. CONFIG_BOOTP_DNS2
  910. CONFIG_BOOTP_SEND_HOSTNAME
  911. CONFIG_BOOTP_NTPSERVER
  912. CONFIG_BOOTP_TIMEOFFSET
  913. CONFIG_BOOTP_VENDOREX
  914. CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
  915. environment variable, not the BOOTP server.
  916. CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
  917. serverip from a DHCP server, it is possible that more
  918. than one DNS serverip is offered to the client.
  919. If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
  920. serverip will be stored in the additional environment
  921. variable "dnsip2". The first DNS serverip is always
  922. stored in the variable "dnsip", when CONFIG_BOOTP_DNS
  923. is defined.
  924. CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
  925. to do a dynamic update of a DNS server. To do this, they
  926. need the hostname of the DHCP requester.
  927. If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
  928. of the "hostname" environment variable is passed as
  929. option 12 to the DHCP server.
  930. CONFIG_BOOTP_DHCP_REQUEST_DELAY
  931. A 32bit value in microseconds for a delay between
  932. receiving a "DHCP Offer" and sending the "DHCP Request".
  933. This fixes a problem with certain DHCP servers that don't
  934. respond 100% of the time to a "DHCP request". E.g. On an
  935. AT91RM9200 processor running at 180MHz, this delay needed
  936. to be *at least* 15,000 usec before a Windows Server 2003
  937. DHCP server would reply 100% of the time. I recommend at
  938. least 50,000 usec to be safe. The alternative is to hope
  939. that one of the retries will be successful but note that
  940. the DHCP timeout and retry process takes a longer than
  941. this delay.
  942. - CDP Options:
  943. CONFIG_CDP_DEVICE_ID
  944. The device id used in CDP trigger frames.
  945. CONFIG_CDP_DEVICE_ID_PREFIX
  946. A two character string which is prefixed to the MAC address
  947. of the device.
  948. CONFIG_CDP_PORT_ID
  949. A printf format string which contains the ascii name of
  950. the port. Normally is set to "eth%d" which sets
  951. eth0 for the first Ethernet, eth1 for the second etc.
  952. CONFIG_CDP_CAPABILITIES
  953. A 32bit integer which indicates the device capabilities;
  954. 0x00000010 for a normal host which does not forwards.
  955. CONFIG_CDP_VERSION
  956. An ascii string containing the version of the software.
  957. CONFIG_CDP_PLATFORM
  958. An ascii string containing the name of the platform.
  959. CONFIG_CDP_TRIGGER
  960. A 32bit integer sent on the trigger.
  961. CONFIG_CDP_POWER_CONSUMPTION
  962. A 16bit integer containing the power consumption of the
  963. device in .1 of milliwatts.
  964. CONFIG_CDP_APPLIANCE_VLAN_TYPE
  965. A byte containing the id of the VLAN.
  966. - Status LED: CONFIG_STATUS_LED
  967. Several configurations allow to display the current
  968. status using a LED. For instance, the LED will blink
  969. fast while running U-Boot code, stop blinking as
  970. soon as a reply to a BOOTP request was received, and
  971. start blinking slow once the Linux kernel is running
  972. (supported by a status LED driver in the Linux
  973. kernel). Defining CONFIG_STATUS_LED enables this
  974. feature in U-Boot.
  975. - CAN Support: CONFIG_CAN_DRIVER
  976. Defining CONFIG_CAN_DRIVER enables CAN driver support
  977. on those systems that support this (optional)
  978. feature, like the TQM8xxL modules.
  979. - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
  980. These enable I2C serial bus commands. Defining either of
  981. (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
  982. include the appropriate I2C driver for the selected CPU.
  983. This will allow you to use i2c commands at the u-boot
  984. command line (as long as you set CONFIG_CMD_I2C in
  985. CONFIG_COMMANDS) and communicate with i2c based realtime
  986. clock chips. See common/cmd_i2c.c for a description of the
  987. command line interface.
  988. CONFIG_I2C_CMD_TREE is a recommended option that places
  989. all I2C commands under a single 'i2c' root command. The
  990. older 'imm', 'imd', 'iprobe' etc. commands are considered
  991. deprecated and may disappear in the future.
  992. CONFIG_HARD_I2C selects a hardware I2C controller.
  993. CONFIG_SOFT_I2C configures u-boot to use a software (aka
  994. bit-banging) driver instead of CPM or similar hardware
  995. support for I2C.
  996. There are several other quantities that must also be
  997. defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
  998. In both cases you will need to define CFG_I2C_SPEED
  999. to be the frequency (in Hz) at which you wish your i2c bus
  1000. to run and CFG_I2C_SLAVE to be the address of this node (ie
  1001. the CPU's i2c node address).
  1002. Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c)
  1003. sets the CPU up as a master node and so its address should
  1004. therefore be cleared to 0 (See, eg, MPC823e User's Manual
  1005. p.16-473). So, set CFG_I2C_SLAVE to 0.
  1006. That's all that's required for CONFIG_HARD_I2C.
  1007. If you use the software i2c interface (CONFIG_SOFT_I2C)
  1008. then the following macros need to be defined (examples are
  1009. from include/configs/lwmon.h):
  1010. I2C_INIT
  1011. (Optional). Any commands necessary to enable the I2C
  1012. controller or configure ports.
  1013. eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
  1014. I2C_PORT
  1015. (Only for MPC8260 CPU). The I/O port to use (the code
  1016. assumes both bits are on the same port). Valid values
  1017. are 0..3 for ports A..D.
  1018. I2C_ACTIVE
  1019. The code necessary to make the I2C data line active
  1020. (driven). If the data line is open collector, this
  1021. define can be null.
  1022. eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
  1023. I2C_TRISTATE
  1024. The code necessary to make the I2C data line tri-stated
  1025. (inactive). If the data line is open collector, this
  1026. define can be null.
  1027. eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
  1028. I2C_READ
  1029. Code that returns TRUE if the I2C data line is high,
  1030. FALSE if it is low.
  1031. eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
  1032. I2C_SDA(bit)
  1033. If <bit> is TRUE, sets the I2C data line high. If it
  1034. is FALSE, it clears it (low).
  1035. eg: #define I2C_SDA(bit) \
  1036. if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
  1037. else immr->im_cpm.cp_pbdat &= ~PB_SDA
  1038. I2C_SCL(bit)
  1039. If <bit> is TRUE, sets the I2C clock line high. If it
  1040. is FALSE, it clears it (low).
  1041. eg: #define I2C_SCL(bit) \
  1042. if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
  1043. else immr->im_cpm.cp_pbdat &= ~PB_SCL
  1044. I2C_DELAY
  1045. This delay is invoked four times per clock cycle so this
  1046. controls the rate of data transfer. The data rate thus
  1047. is 1 / (I2C_DELAY * 4). Often defined to be something
  1048. like:
  1049. #define I2C_DELAY udelay(2)
  1050. CFG_I2C_INIT_BOARD
  1051. When a board is reset during an i2c bus transfer
  1052. chips might think that the current transfer is still
  1053. in progress. On some boards it is possible to access
  1054. the i2c SCLK line directly, either by using the
  1055. processor pin as a GPIO or by having a second pin
  1056. connected to the bus. If this option is defined a
  1057. custom i2c_init_board() routine in boards/xxx/board.c
  1058. is run early in the boot sequence.
  1059. CONFIG_I2CFAST (PPC405GP|PPC405EP only)
  1060. This option enables configuration of bi_iic_fast[] flags
  1061. in u-boot bd_info structure based on u-boot environment
  1062. variable "i2cfast". (see also i2cfast)
  1063. CONFIG_I2C_MULTI_BUS
  1064. This option allows the use of multiple I2C buses, each of which
  1065. must have a controller. At any point in time, only one bus is
  1066. active. To switch to a different bus, use the 'i2c dev' command.
  1067. Note that bus numbering is zero-based.
  1068. CFG_I2C_NOPROBES
  1069. This option specifies a list of I2C devices that will be skipped
  1070. when the 'i2c probe' command is issued (or 'iprobe' using the legacy
  1071. command). If CONFIG_I2C_MULTI_BUS is set, specify a list of bus-device
  1072. pairs. Otherwise, specify a 1D array of device addresses
  1073. e.g.
  1074. #undef CONFIG_I2C_MULTI_BUS
  1075. #define CFG_I2C_NOPROBES {0x50,0x68}
  1076. will skip addresses 0x50 and 0x68 on a board with one I2C bus
  1077. #define CONFIG_I2C_MULTI_BUS
  1078. #define CFG_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
  1079. will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
  1080. CFG_SPD_BUS_NUM
  1081. If defined, then this indicates the I2C bus number for DDR SPD.
  1082. If not defined, then U-Boot assumes that SPD is on I2C bus 0.
  1083. CFG_RTC_BUS_NUM
  1084. If defined, then this indicates the I2C bus number for the RTC.
  1085. If not defined, then U-Boot assumes that RTC is on I2C bus 0.
  1086. CFG_DTT_BUS_NUM
  1087. If defined, then this indicates the I2C bus number for the DTT.
  1088. If not defined, then U-Boot assumes that DTT is on I2C bus 0.
  1089. CFG_I2C_DTT_ADDR:
  1090. If defined, specifies the I2C address of the DTT device.
  1091. If not defined, then U-Boot uses predefined value for
  1092. specified DTT device.
  1093. CONFIG_FSL_I2C
  1094. Define this option if you want to use Freescale's I2C driver in
  1095. drivers/i2c/fsl_i2c.c.
  1096. - SPI Support: CONFIG_SPI
  1097. Enables SPI driver (so far only tested with
  1098. SPI EEPROM, also an instance works with Crystal A/D and
  1099. D/As on the SACSng board)
  1100. CONFIG_SPI_X
  1101. Enables extended (16-bit) SPI EEPROM addressing.
  1102. (symmetrical to CONFIG_I2C_X)
  1103. CONFIG_SOFT_SPI
  1104. Enables a software (bit-bang) SPI driver rather than
  1105. using hardware support. This is a general purpose
  1106. driver that only requires three general I/O port pins
  1107. (two outputs, one input) to function. If this is
  1108. defined, the board configuration must define several
  1109. SPI configuration items (port pins to use, etc). For
  1110. an example, see include/configs/sacsng.h.
  1111. CONFIG_HARD_SPI
  1112. Enables a hardware SPI driver for general-purpose reads
  1113. and writes. As with CONFIG_SOFT_SPI, the board configuration
  1114. must define a list of chip-select function pointers.
  1115. Currently supported on some MPC8xxx processors. For an
  1116. example, see include/configs/mpc8349emds.h.
  1117. CONFIG_MXC_SPI
  1118. Enables the driver for the SPI controllers on i.MX and MXC
  1119. SoCs. Currently only i.MX31 is supported.
  1120. - FPGA Support: CONFIG_FPGA
  1121. Enables FPGA subsystem.
  1122. CONFIG_FPGA_<vendor>
  1123. Enables support for specific chip vendors.
  1124. (ALTERA, XILINX)
  1125. CONFIG_FPGA_<family>
  1126. Enables support for FPGA family.
  1127. (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
  1128. CONFIG_FPGA_COUNT
  1129. Specify the number of FPGA devices to support.
  1130. CFG_FPGA_PROG_FEEDBACK
  1131. Enable printing of hash marks during FPGA configuration.
  1132. CFG_FPGA_CHECK_BUSY
  1133. Enable checks on FPGA configuration interface busy
  1134. status by the configuration function. This option
  1135. will require a board or device specific function to
  1136. be written.
  1137. CONFIG_FPGA_DELAY
  1138. If defined, a function that provides delays in the FPGA
  1139. configuration driver.
  1140. CFG_FPGA_CHECK_CTRLC
  1141. Allow Control-C to interrupt FPGA configuration
  1142. CFG_FPGA_CHECK_ERROR
  1143. Check for configuration errors during FPGA bitfile
  1144. loading. For example, abort during Virtex II
  1145. configuration if the INIT_B line goes low (which
  1146. indicated a CRC error).
  1147. CFG_FPGA_WAIT_INIT
  1148. Maximum time to wait for the INIT_B line to deassert
  1149. after PROB_B has been deasserted during a Virtex II
  1150. FPGA configuration sequence. The default time is 500
  1151. ms.
  1152. CFG_FPGA_WAIT_BUSY
  1153. Maximum time to wait for BUSY to deassert during
  1154. Virtex II FPGA configuration. The default is 5 ms.
  1155. CFG_FPGA_WAIT_CONFIG
  1156. Time to wait after FPGA configuration. The default is
  1157. 200 ms.
  1158. - Configuration Management:
  1159. CONFIG_IDENT_STRING
  1160. If defined, this string will be added to the U-Boot
  1161. version information (U_BOOT_VERSION)
  1162. - Vendor Parameter Protection:
  1163. U-Boot considers the values of the environment
  1164. variables "serial#" (Board Serial Number) and
  1165. "ethaddr" (Ethernet Address) to be parameters that
  1166. are set once by the board vendor / manufacturer, and
  1167. protects these variables from casual modification by
  1168. the user. Once set, these variables are read-only,
  1169. and write or delete attempts are rejected. You can
  1170. change this behaviour:
  1171. If CONFIG_ENV_OVERWRITE is #defined in your config
  1172. file, the write protection for vendor parameters is
  1173. completely disabled. Anybody can change or delete
  1174. these parameters.
  1175. Alternatively, if you #define _both_ CONFIG_ETHADDR
  1176. _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
  1177. Ethernet address is installed in the environment,
  1178. which can be changed exactly ONCE by the user. [The
  1179. serial# is unaffected by this, i. e. it remains
  1180. read-only.]
  1181. - Protected RAM:
  1182. CONFIG_PRAM
  1183. Define this variable to enable the reservation of
  1184. "protected RAM", i. e. RAM which is not overwritten
  1185. by U-Boot. Define CONFIG_PRAM to hold the number of
  1186. kB you want to reserve for pRAM. You can overwrite
  1187. this default value by defining an environment
  1188. variable "pram" to the number of kB you want to
  1189. reserve. Note that the board info structure will
  1190. still show the full amount of RAM. If pRAM is
  1191. reserved, a new environment variable "mem" will
  1192. automatically be defined to hold the amount of
  1193. remaining RAM in a form that can be passed as boot
  1194. argument to Linux, for instance like that:
  1195. setenv bootargs ... mem=\${mem}
  1196. saveenv
  1197. This way you can tell Linux not to use this memory,
  1198. either, which results in a memory region that will
  1199. not be affected by reboots.
  1200. *WARNING* If your board configuration uses automatic
  1201. detection of the RAM size, you must make sure that
  1202. this memory test is non-destructive. So far, the
  1203. following board configurations are known to be
  1204. "pRAM-clean":
  1205. ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
  1206. HERMES, IP860, RPXlite, LWMON, LANTEC,
  1207. PCU_E, FLAGADM, TQM8260
  1208. - Error Recovery:
  1209. CONFIG_PANIC_HANG
  1210. Define this variable to stop the system in case of a
  1211. fatal error, so that you have to reset it manually.
  1212. This is probably NOT a good idea for an embedded
  1213. system where you want the system to reboot
  1214. automatically as fast as possible, but it may be
  1215. useful during development since you can try to debug
  1216. the conditions that lead to the situation.
  1217. CONFIG_NET_RETRY_COUNT
  1218. This variable defines the number of retries for
  1219. network operations like ARP, RARP, TFTP, or BOOTP
  1220. before giving up the operation. If not defined, a
  1221. default value of 5 is used.
  1222. CONFIG_ARP_TIMEOUT
  1223. Timeout waiting for an ARP reply in milliseconds.
  1224. - Command Interpreter:
  1225. CONFIG_AUTO_COMPLETE
  1226. Enable auto completion of commands using TAB.
  1227. Note that this feature has NOT been implemented yet
  1228. for the "hush" shell.
  1229. CFG_HUSH_PARSER
  1230. Define this variable to enable the "hush" shell (from
  1231. Busybox) as command line interpreter, thus enabling
  1232. powerful command line syntax like
  1233. if...then...else...fi conditionals or `&&' and '||'
  1234. constructs ("shell scripts").
  1235. If undefined, you get the old, much simpler behaviour
  1236. with a somewhat smaller memory footprint.
  1237. CFG_PROMPT_HUSH_PS2
  1238. This defines the secondary prompt string, which is
  1239. printed when the command interpreter needs more input
  1240. to complete a command. Usually "> ".
  1241. Note:
  1242. In the current implementation, the local variables
  1243. space and global environment variables space are
  1244. separated. Local variables are those you define by
  1245. simply typing `name=value'. To access a local
  1246. variable later on, you have write `$name' or
  1247. `${name}'; to execute the contents of a variable
  1248. directly type `$name' at the command prompt.
  1249. Global environment variables are those you use
  1250. setenv/printenv to work with. To run a command stored
  1251. in such a variable, you need to use the run command,
  1252. and you must not use the '$' sign to access them.
  1253. To store commands and special characters in a
  1254. variable, please use double quotation marks
  1255. surrounding the whole text of the variable, instead
  1256. of the backslashes before semicolons and special
  1257. symbols.
  1258. - Commandline Editing and History:
  1259. CONFIG_CMDLINE_EDITING
  1260. Enable editing and History functions for interactive
  1261. commandline input operations
  1262. - Default Environment:
  1263. CONFIG_EXTRA_ENV_SETTINGS
  1264. Define this to contain any number of null terminated
  1265. strings (variable = value pairs) that will be part of
  1266. the default environment compiled into the boot image.
  1267. For example, place something like this in your
  1268. board's config file:
  1269. #define CONFIG_EXTRA_ENV_SETTINGS \
  1270. "myvar1=value1\0" \
  1271. "myvar2=value2\0"
  1272. Warning: This method is based on knowledge about the
  1273. internal format how the environment is stored by the
  1274. U-Boot code. This is NOT an official, exported
  1275. interface! Although it is unlikely that this format
  1276. will change soon, there is no guarantee either.
  1277. You better know what you are doing here.
  1278. Note: overly (ab)use of the default environment is
  1279. discouraged. Make sure to check other ways to preset
  1280. the environment like the autoscript function or the
  1281. boot command first.
  1282. - DataFlash Support:
  1283. CONFIG_HAS_DATAFLASH
  1284. Defining this option enables DataFlash features and
  1285. allows to read/write in Dataflash via the standard
  1286. commands cp, md...
  1287. - SystemACE Support:
  1288. CONFIG_SYSTEMACE
  1289. Adding this option adds support for Xilinx SystemACE
  1290. chips attached via some sort of local bus. The address
  1291. of the chip must also be defined in the
  1292. CFG_SYSTEMACE_BASE macro. For example:
  1293. #define CONFIG_SYSTEMACE
  1294. #define CFG_SYSTEMACE_BASE 0xf0000000
  1295. When SystemACE support is added, the "ace" device type
  1296. becomes available to the fat commands, i.e. fatls.
  1297. - TFTP Fixed UDP Port:
  1298. CONFIG_TFTP_PORT
  1299. If this is defined, the environment variable tftpsrcp
  1300. is used to supply the TFTP UDP source port value.
  1301. If tftpsrcp isn't defined, the normal pseudo-random port
  1302. number generator is used.
  1303. Also, the environment variable tftpdstp is used to supply
  1304. the TFTP UDP destination port value. If tftpdstp isn't
  1305. defined, the normal port 69 is used.
  1306. The purpose for tftpsrcp is to allow a TFTP server to
  1307. blindly start the TFTP transfer using the pre-configured
  1308. target IP address and UDP port. This has the effect of
  1309. "punching through" the (Windows XP) firewall, allowing
  1310. the remainder of the TFTP transfer to proceed normally.
  1311. A better solution is to properly configure the firewall,
  1312. but sometimes that is not allowed.
  1313. - Show boot progress:
  1314. CONFIG_SHOW_BOOT_PROGRESS
  1315. Defining this option allows to add some board-
  1316. specific code (calling a user-provided function
  1317. "show_boot_progress(int)") that enables you to show
  1318. the system's boot progress on some display (for
  1319. example, some LED's) on your board. At the moment,
  1320. the following checkpoints are implemented:
  1321. - Automatic software updates via TFTP server
  1322. CONFIG_UPDATE_TFTP
  1323. CONFIG_UPDATE_TFTP_CNT_MAX
  1324. CONFIG_UPDATE_TFTP_MSEC_MAX
  1325. These options enable and control the auto-update feature;
  1326. for a more detailed description refer to doc/README.update.
  1327. Legacy uImage format:
  1328. Arg Where When
  1329. 1 common/cmd_bootm.c before attempting to boot an image
  1330. -1 common/cmd_bootm.c Image header has bad magic number
  1331. 2 common/cmd_bootm.c Image header has correct magic number
  1332. -2 common/cmd_bootm.c Image header has bad checksum
  1333. 3 common/cmd_bootm.c Image header has correct checksum
  1334. -3 common/cmd_bootm.c Image data has bad checksum
  1335. 4 common/cmd_bootm.c Image data has correct checksum
  1336. -4 common/cmd_bootm.c Image is for unsupported architecture
  1337. 5 common/cmd_bootm.c Architecture check OK
  1338. -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
  1339. 6 common/cmd_bootm.c Image Type check OK
  1340. -6 common/cmd_bootm.c gunzip uncompression error
  1341. -7 common/cmd_bootm.c Unimplemented compression type
  1342. 7 common/cmd_bootm.c Uncompression OK
  1343. 8 common/cmd_bootm.c No uncompress/copy overwrite error
  1344. -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
  1345. 9 common/image.c Start initial ramdisk verification
  1346. -10 common/image.c Ramdisk header has bad magic number
  1347. -11 common/image.c Ramdisk header has bad checksum
  1348. 10 common/image.c Ramdisk header is OK
  1349. -12 common/image.c Ramdisk data has bad checksum
  1350. 11 common/image.c Ramdisk data has correct checksum
  1351. 12 common/image.c Ramdisk verification complete, start loading
  1352. -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
  1353. 13 common/image.c Start multifile image verification
  1354. 14 common/image.c No initial ramdisk, no multifile, continue.
  1355. 15 lib_<arch>/bootm.c All preparation done, transferring control to OS
  1356. -30 lib_ppc/board.c Fatal error, hang the system
  1357. -31 post/post.c POST test failed, detected by post_output_backlog()
  1358. -32 post/post.c POST test failed, detected by post_run_single()
  1359. 34 common/cmd_doc.c before loading a Image from a DOC device
  1360. -35 common/cmd_doc.c Bad usage of "doc" command
  1361. 35 common/cmd_doc.c correct usage of "doc" command
  1362. -36 common/cmd_doc.c No boot device
  1363. 36 common/cmd_doc.c correct boot device
  1364. -37 common/cmd_doc.c Unknown Chip ID on boot device
  1365. 37 common/cmd_doc.c correct chip ID found, device available
  1366. -38 common/cmd_doc.c Read Error on boot device
  1367. 38 common/cmd_doc.c reading Image header from DOC device OK
  1368. -39 common/cmd_doc.c Image header has bad magic number
  1369. 39 common/cmd_doc.c Image header has correct magic number
  1370. -40 common/cmd_doc.c Error reading Image from DOC device
  1371. 40 common/cmd_doc.c Image header has correct magic number
  1372. 41 common/cmd_ide.c before loading a Image from a IDE device
  1373. -42 common/cmd_ide.c Bad usage of "ide" command
  1374. 42 common/cmd_ide.c correct usage of "ide" command
  1375. -43 common/cmd_ide.c No boot device
  1376. 43 common/cmd_ide.c boot device found
  1377. -44 common/cmd_ide.c Device not available
  1378. 44 common/cmd_ide.c Device available
  1379. -45 common/cmd_ide.c wrong partition selected
  1380. 45 common/cmd_ide.c partition selected
  1381. -46 common/cmd_ide.c Unknown partition table
  1382. 46 common/cmd_ide.c valid partition table found
  1383. -47 common/cmd_ide.c Invalid partition type
  1384. 47 common/cmd_ide.c correct partition type
  1385. -48 common/cmd_ide.c Error reading Image Header on boot device
  1386. 48 common/cmd_ide.c reading Image Header from IDE device OK
  1387. -49 common/cmd_ide.c Image header has bad magic number
  1388. 49 common/cmd_ide.c Image header has correct magic number
  1389. -50 common/cmd_ide.c Image header has bad checksum
  1390. 50 common/cmd_ide.c Image header has correct checksum
  1391. -51 common/cmd_ide.c Error reading Image from IDE device
  1392. 51 common/cmd_ide.c reading Image from IDE device OK
  1393. 52 common/cmd_nand.c before loading a Image from a NAND device
  1394. -53 common/cmd_nand.c Bad usage of "nand" command
  1395. 53 common/cmd_nand.c correct usage of "nand" command
  1396. -54 common/cmd_nand.c No boot device
  1397. 54 common/cmd_nand.c boot device found
  1398. -55 common/cmd_nand.c Unknown Chip ID on boot device
  1399. 55 common/cmd_nand.c correct chip ID found, device available
  1400. -56 common/cmd_nand.c Error reading Image Header on boot device
  1401. 56 common/cmd_nand.c reading Image Header from NAND device OK
  1402. -57 common/cmd_nand.c Image header has bad magic number
  1403. 57 common/cmd_nand.c Image header has correct magic number
  1404. -58 common/cmd_nand.c Error reading Image from NAND device
  1405. 58 common/cmd_nand.c reading Image from NAND device OK
  1406. -60 common/env_common.c Environment has a bad CRC, using default
  1407. 64 net/eth.c starting with Ethernet configuration.
  1408. -64 net/eth.c no Ethernet found.
  1409. 65 net/eth.c Ethernet found.
  1410. -80 common/cmd_net.c usage wrong
  1411. 80 common/cmd_net.c before calling NetLoop()
  1412. -81 common/cmd_net.c some error in NetLoop() occurred
  1413. 81 common/cmd_net.c NetLoop() back without error
  1414. -82 common/cmd_net.c size == 0 (File with size 0 loaded)
  1415. 82 common/cmd_net.c trying automatic boot
  1416. 83 common/cmd_net.c running autoscript
  1417. -83 common/cmd_net.c some error in automatic boot or autoscript
  1418. 84 common/cmd_net.c end without errors
  1419. FIT uImage format:
  1420. Arg Where When
  1421. 100 common/cmd_bootm.c Kernel FIT Image has correct format
  1422. -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
  1423. 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
  1424. -101 common/cmd_bootm.c Can't get configuration for kernel subimage
  1425. 102 common/cmd_bootm.c Kernel unit name specified
  1426. -103 common/cmd_bootm.c Can't get kernel subimage node offset
  1427. 103 common/cmd_bootm.c Found configuration node
  1428. 104 common/cmd_bootm.c Got kernel subimage node offset
  1429. -104 common/cmd_bootm.c Kernel subimage hash verification failed
  1430. 105 common/cmd_bootm.c Kernel subimage hash verification OK
  1431. -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
  1432. 106 common/cmd_bootm.c Architecture check OK
  1433. -106 common/cmd_bootm.c Kernel subimage has wrong type
  1434. 107 common/cmd_bootm.c Kernel subimage type OK
  1435. -107 common/cmd_bootm.c Can't get kernel subimage data/size
  1436. 108 common/cmd_bootm.c Got kernel subimage data/size
  1437. -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
  1438. -109 common/cmd_bootm.c Can't get kernel subimage type
  1439. -110 common/cmd_bootm.c Can't get kernel subimage comp
  1440. -111 common/cmd_bootm.c Can't get kernel subimage os
  1441. -112 common/cmd_bootm.c Can't get kernel subimage load address
  1442. -113 common/cmd_bootm.c Image uncompress/copy overwrite error
  1443. 120 common/image.c Start initial ramdisk verification
  1444. -120 common/image.c Ramdisk FIT image has incorrect format
  1445. 121 common/image.c Ramdisk FIT image has correct format
  1446. 122 common/image.c No ramdisk subimage unit name, using configuration
  1447. -122 common/image.c Can't get configuration for ramdisk subimage
  1448. 123 common/image.c Ramdisk unit name specified
  1449. -124 common/image.c Can't get ramdisk subimage node offset
  1450. 125 common/image.c Got ramdisk subimage node offset
  1451. -125 common/image.c Ramdisk subimage hash verification failed
  1452. 126 common/image.c Ramdisk subimage hash verification OK
  1453. -126 common/image.c Ramdisk subimage for unsupported architecture
  1454. 127 common/image.c Architecture check OK
  1455. -127 common/image.c Can't get ramdisk subimage data/size
  1456. 128 common/image.c Got ramdisk subimage data/size
  1457. 129 common/image.c Can't get ramdisk load address
  1458. -129 common/image.c Got ramdisk load address
  1459. -130 common/cmd_doc.c Incorrect FIT image format
  1460. 131 common/cmd_doc.c FIT image format OK
  1461. -140 common/cmd_ide.c Incorrect FIT image format
  1462. 141 common/cmd_ide.c FIT image format OK
  1463. -150 common/cmd_nand.c Incorrect FIT image format
  1464. 151 common/cmd_nand.c FIT image format OK
  1465. Modem Support:
  1466. --------------
  1467. [so far only for SMDK2400 and TRAB boards]
  1468. - Modem support enable:
  1469. CONFIG_MODEM_SUPPORT
  1470. - RTS/CTS Flow control enable:
  1471. CONFIG_HWFLOW
  1472. - Modem debug support:
  1473. CONFIG_MODEM_SUPPORT_DEBUG
  1474. Enables debugging stuff (char screen[1024], dbg())
  1475. for modem support. Useful only with BDI2000.
  1476. - Interrupt support (PPC):
  1477. There are common interrupt_init() and timer_interrupt()
  1478. for all PPC archs. interrupt_init() calls interrupt_init_cpu()
  1479. for CPU specific initialization. interrupt_init_cpu()
  1480. should set decrementer_count to appropriate value. If
  1481. CPU resets decrementer automatically after interrupt
  1482. (ppc4xx) it should set decrementer_count to zero.
  1483. timer_interrupt() calls timer_interrupt_cpu() for CPU
  1484. specific handling. If board has watchdog / status_led
  1485. / other_activity_monitor it works automatically from
  1486. general timer_interrupt().
  1487. - General:
  1488. In the target system modem support is enabled when a
  1489. specific key (key combination) is pressed during
  1490. power-on. Otherwise U-Boot will boot normally
  1491. (autoboot). The key_pressed() function is called from
  1492. board_init(). Currently key_pressed() is a dummy
  1493. function, returning 1 and thus enabling modem
  1494. initialization.
  1495. If there are no modem init strings in the
  1496. environment, U-Boot proceed to autoboot; the
  1497. previous output (banner, info printfs) will be
  1498. suppressed, though.
  1499. See also: doc/README.Modem
  1500. Configuration Settings:
  1501. -----------------------
  1502. - CFG_LONGHELP: Defined when you want long help messages included;
  1503. undefine this when you're short of memory.
  1504. - CFG_PROMPT: This is what U-Boot prints on the console to
  1505. prompt for user input.
  1506. - CFG_CBSIZE: Buffer size for input from the Console
  1507. - CFG_PBSIZE: Buffer size for Console output
  1508. - CFG_MAXARGS: max. Number of arguments accepted for monitor commands
  1509. - CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to
  1510. the application (usually a Linux kernel) when it is
  1511. booted
  1512. - CFG_BAUDRATE_TABLE:
  1513. List of legal baudrate settings for this board.
  1514. - CFG_CONSOLE_INFO_QUIET
  1515. Suppress display of console information at boot.
  1516. - CFG_CONSOLE_IS_IN_ENV
  1517. If the board specific function
  1518. extern int overwrite_console (void);
  1519. returns 1, the stdin, stderr and stdout are switched to the
  1520. serial port, else the settings in the environment are used.
  1521. - CFG_CONSOLE_OVERWRITE_ROUTINE
  1522. Enable the call to overwrite_console().
  1523. - CFG_CONSOLE_ENV_OVERWRITE
  1524. Enable overwrite of previous console environment settings.
  1525. - CFG_MEMTEST_START, CFG_MEMTEST_END:
  1526. Begin and End addresses of the area used by the
  1527. simple memory test.
  1528. - CFG_ALT_MEMTEST:
  1529. Enable an alternate, more extensive memory test.
  1530. - CFG_MEMTEST_SCRATCH:
  1531. Scratch address used by the alternate memory test
  1532. You only need to set this if address zero isn't writeable
  1533. - CFG_MEM_TOP_HIDE (PPC only):
  1534. If CFG_MEM_TOP_HIDE is defined in the board config header,
  1535. this specified memory area will get subtracted from the top
  1536. (end) of RAM and won't get "touched" at all by U-Boot. By
  1537. fixing up gd->ram_size the Linux kernel should gets passed
  1538. the now "corrected" memory size and won't touch it either.
  1539. This should work for arch/ppc and arch/powerpc. Only Linux
  1540. board ports in arch/powerpc with bootwrapper support that
  1541. recalculate the memory size from the SDRAM controller setup
  1542. will have to get fixed in Linux additionally.
  1543. This option can be used as a workaround for the 440EPx/GRx
  1544. CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
  1545. be touched.
  1546. WARNING: Please make sure that this value is a multiple of
  1547. the Linux page size (normally 4k). If this is not the case,
  1548. then the end address of the Linux memory will be located at a
  1549. non page size aligned address and this could cause major
  1550. problems.
  1551. - CFG_TFTP_LOADADDR:
  1552. Default load address for network file downloads
  1553. - CFG_LOADS_BAUD_CHANGE:
  1554. Enable temporary baudrate change while serial download
  1555. - CFG_SDRAM_BASE:
  1556. Physical start address of SDRAM. _Must_ be 0 here.
  1557. - CFG_MBIO_BASE:
  1558. Physical start address of Motherboard I/O (if using a
  1559. Cogent motherboard)
  1560. - CFG_FLASH_BASE:
  1561. Physical start address of Flash memory.
  1562. - CFG_MONITOR_BASE:
  1563. Physical start address of boot monitor code (set by
  1564. make config files to be same as the text base address
  1565. (TEXT_BASE) used when linking) - same as
  1566. CFG_FLASH_BASE when booting from flash.
  1567. - CFG_MONITOR_LEN:
  1568. Size of memory reserved for monitor code, used to
  1569. determine _at_compile_time_ (!) if the environment is
  1570. embedded within the U-Boot image, or in a separate
  1571. flash sector.
  1572. - CFG_MALLOC_LEN:
  1573. Size of DRAM reserved for malloc() use.
  1574. - CFG_BOOTM_LEN:
  1575. Normally compressed uImages are limited to an
  1576. uncompressed size of 8 MBytes. If this is not enough,
  1577. you can define CFG_BOOTM_LEN in your board config file
  1578. to adjust this setting to your needs.
  1579. - CFG_BOOTMAPSZ:
  1580. Maximum size of memory mapped by the startup code of
  1581. the Linux kernel; all data that must be processed by
  1582. the Linux kernel (bd_info, boot arguments, FDT blob if
  1583. used) must be put below this limit, unless "bootm_low"
  1584. enviroment variable is defined and non-zero. In such case
  1585. all data for the Linux kernel must be between "bootm_low"
  1586. and "bootm_low" + CFG_BOOTMAPSZ.
  1587. - CFG_MAX_FLASH_BANKS:
  1588. Max number of Flash memory banks
  1589. - CFG_MAX_FLASH_SECT:
  1590. Max number of sectors on a Flash chip
  1591. - CFG_FLASH_ERASE_TOUT:
  1592. Timeout for Flash erase operations (in ms)
  1593. - CFG_FLASH_WRITE_TOUT:
  1594. Timeout for Flash write operations (in ms)
  1595. - CFG_FLASH_LOCK_TOUT
  1596. Timeout for Flash set sector lock bit operation (in ms)
  1597. - CFG_FLASH_UNLOCK_TOUT
  1598. Timeout for Flash clear lock bits operation (in ms)
  1599. - CFG_FLASH_PROTECTION
  1600. If defined, hardware flash sectors protection is used
  1601. instead of U-Boot software protection.
  1602. - CFG_DIRECT_FLASH_TFTP:
  1603. Enable TFTP transfers directly to flash memory;
  1604. without this option such a download has to be
  1605. performed in two steps: (1) download to RAM, and (2)
  1606. copy from RAM to flash.
  1607. The two-step approach is usually more reliable, since
  1608. you can check if the download worked before you erase
  1609. the flash, but in some situations (when system RAM is
  1610. too limited to allow for a temporary copy of the
  1611. downloaded image) this option may be very useful.
  1612. - CFG_FLASH_CFI:
  1613. Define if the flash driver uses extra elements in the
  1614. common flash structure for storing flash geometry.
  1615. - CONFIG_FLASH_CFI_DRIVER
  1616. This option also enables the building of the cfi_flash driver
  1617. in the drivers directory
  1618. - CFG_FLASH_USE_BUFFER_WRITE
  1619. Use buffered writes to flash.
  1620. - CONFIG_FLASH_SPANSION_S29WS_N
  1621. s29ws-n MirrorBit flash has non-standard addresses for buffered
  1622. write commands.
  1623. - CFG_FLASH_QUIET_TEST
  1624. If this option is defined, the common CFI flash doesn't
  1625. print it's warning upon not recognized FLASH banks. This
  1626. is useful, if some of the configured banks are only
  1627. optionally available.
  1628. - CONFIG_FLASH_SHOW_PROGRESS
  1629. If defined (must be an integer), print out countdown
  1630. digits and dots. Recommended value: 45 (9..1) for 80
  1631. column displays, 15 (3..1) for 40 column displays.
  1632. - CFG_RX_ETH_BUFFER:
  1633. Defines the number of Ethernet receive buffers. On some
  1634. Ethernet controllers it is recommended to set this value
  1635. to 8 or even higher (EEPRO100 or 405 EMAC), since all
  1636. buffers can be full shortly after enabling the interface
  1637. on high Ethernet traffic.
  1638. Defaults to 4 if not defined.
  1639. The following definitions that deal with the placement and management
  1640. of environment data (variable area); in general, we support the
  1641. following configurations:
  1642. - CONFIG_ENV_IS_IN_FLASH:
  1643. Define this if the environment is in flash memory.
  1644. a) The environment occupies one whole flash sector, which is
  1645. "embedded" in the text segment with the U-Boot code. This
  1646. happens usually with "bottom boot sector" or "top boot
  1647. sector" type flash chips, which have several smaller
  1648. sectors at the start or the end. For instance, such a
  1649. layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
  1650. such a case you would place the environment in one of the
  1651. 4 kB sectors - with U-Boot code before and after it. With
  1652. "top boot sector" type flash chips, you would put the
  1653. environment in one of the last sectors, leaving a gap
  1654. between U-Boot and the environment.
  1655. - CONFIG_ENV_OFFSET:
  1656. Offset of environment data (variable area) to the
  1657. beginning of flash memory; for instance, with bottom boot
  1658. type flash chips the second sector can be used: the offset
  1659. for this sector is given here.
  1660. CONFIG_ENV_OFFSET is used relative to CFG_FLASH_BASE.
  1661. - CONFIG_ENV_ADDR:
  1662. This is just another way to specify the start address of
  1663. the flash sector containing the environment (instead of
  1664. CONFIG_ENV_OFFSET).
  1665. - CONFIG_ENV_SECT_SIZE:
  1666. Size of the sector containing the environment.
  1667. b) Sometimes flash chips have few, equal sized, BIG sectors.
  1668. In such a case you don't want to spend a whole sector for
  1669. the environment.
  1670. - CONFIG_ENV_SIZE:
  1671. If you use this in combination with CONFIG_ENV_IS_IN_FLASH
  1672. and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
  1673. of this flash sector for the environment. This saves
  1674. memory for the RAM copy of the environment.
  1675. It may also save flash memory if you decide to use this
  1676. when your environment is "embedded" within U-Boot code,
  1677. since then the remainder of the flash sector could be used
  1678. for U-Boot code. It should be pointed out that this is
  1679. STRONGLY DISCOURAGED from a robustness point of view:
  1680. updating the environment in flash makes it always
  1681. necessary to erase the WHOLE sector. If something goes
  1682. wrong before the contents has been restored from a copy in
  1683. RAM, your target system will be dead.
  1684. - CONFIG_ENV_ADDR_REDUND
  1685. CONFIG_ENV_SIZE_REDUND
  1686. These settings describe a second storage area used to hold
  1687. a redundant copy of the environment data, so that there is
  1688. a valid backup copy in case there is a power failure during
  1689. a "saveenv" operation.
  1690. BE CAREFUL! Any changes to the flash layout, and some changes to the
  1691. source code will make it necessary to adapt <board>/u-boot.lds*
  1692. accordingly!
  1693. - CONFIG_ENV_IS_IN_NVRAM:
  1694. Define this if you have some non-volatile memory device
  1695. (NVRAM, battery buffered SRAM) which you want to use for the
  1696. environment.
  1697. - CONFIG_ENV_ADDR:
  1698. - CONFIG_ENV_SIZE:
  1699. These two #defines are used to determine the memory area you
  1700. want to use for environment. It is assumed that this memory
  1701. can just be read and written to, without any special
  1702. provision.
  1703. BE CAREFUL! The first access to the environment happens quite early
  1704. in U-Boot initalization (when we try to get the setting of for the
  1705. console baudrate). You *MUST* have mapped your NVRAM area then, or
  1706. U-Boot will hang.
  1707. Please note that even with NVRAM we still use a copy of the
  1708. environment in RAM: we could work on NVRAM directly, but we want to
  1709. keep settings there always unmodified except somebody uses "saveenv"
  1710. to save the current settings.
  1711. - CONFIG_ENV_IS_IN_EEPROM:
  1712. Use this if you have an EEPROM or similar serial access
  1713. device and a driver for it.
  1714. - CONFIG_ENV_OFFSET:
  1715. - CONFIG_ENV_SIZE:
  1716. These two #defines specify the offset and size of the
  1717. environment area within the total memory of your EEPROM.
  1718. - CFG_I2C_EEPROM_ADDR:
  1719. If defined, specified the chip address of the EEPROM device.
  1720. The default address is zero.
  1721. - CFG_EEPROM_PAGE_WRITE_BITS:
  1722. If defined, the number of bits used to address bytes in a
  1723. single page in the EEPROM device. A 64 byte page, for example
  1724. would require six bits.
  1725. - CFG_EEPROM_PAGE_WRITE_DELAY_MS:
  1726. If defined, the number of milliseconds to delay between
  1727. page writes. The default is zero milliseconds.
  1728. - CFG_I2C_EEPROM_ADDR_LEN:
  1729. The length in bytes of the EEPROM memory array address. Note
  1730. that this is NOT the chip address length!
  1731. - CFG_I2C_EEPROM_ADDR_OVERFLOW:
  1732. EEPROM chips that implement "address overflow" are ones
  1733. like Catalyst 24WC04/08/16 which has 9/10/11 bits of
  1734. address and the extra bits end up in the "chip address" bit
  1735. slots. This makes a 24WC08 (1Kbyte) chip look like four 256
  1736. byte chips.
  1737. Note that we consider the length of the address field to
  1738. still be one byte because the extra address bits are hidden
  1739. in the chip address.
  1740. - CFG_EEPROM_SIZE:
  1741. The size in bytes of the EEPROM device.
  1742. - CONFIG_ENV_IS_IN_DATAFLASH:
  1743. Define this if you have a DataFlash memory device which you
  1744. want to use for the environment.
  1745. - CONFIG_ENV_OFFSET:
  1746. - CONFIG_ENV_ADDR:
  1747. - CONFIG_ENV_SIZE:
  1748. These three #defines specify the offset and size of the
  1749. environment area within the total memory of your DataFlash placed
  1750. at the specified address.
  1751. - CONFIG_ENV_IS_IN_NAND:
  1752. Define this if you have a NAND device which you want to use
  1753. for the environment.
  1754. - CONFIG_ENV_OFFSET:
  1755. - CONFIG_ENV_SIZE:
  1756. These two #defines specify the offset and size of the environment
  1757. area within the first NAND device.
  1758. - CONFIG_ENV_OFFSET_REDUND
  1759. This setting describes a second storage area of CONFIG_ENV_SIZE
  1760. size used to hold a redundant copy of the environment data,
  1761. so that there is a valid backup copy in case there is a
  1762. power failure during a "saveenv" operation.
  1763. Note: CONFIG_ENV_OFFSET and CONFIG_ENV_OFFSET_REDUND must be aligned
  1764. to a block boundary, and CONFIG_ENV_SIZE must be a multiple of
  1765. the NAND devices block size.
  1766. - CFG_SPI_INIT_OFFSET
  1767. Defines offset to the initial SPI buffer area in DPRAM. The
  1768. area is used at an early stage (ROM part) if the environment
  1769. is configured to reside in the SPI EEPROM: We need a 520 byte
  1770. scratch DPRAM area. It is used between the two initialization
  1771. calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
  1772. to be a good choice since it makes it far enough from the
  1773. start of the data area as well as from the stack pointer.
  1774. Please note that the environment is read-only until the monitor
  1775. has been relocated to RAM and a RAM copy of the environment has been
  1776. created; also, when using EEPROM you will have to use getenv_r()
  1777. until then to read environment variables.
  1778. The environment is protected by a CRC32 checksum. Before the monitor
  1779. is relocated into RAM, as a result of a bad CRC you will be working
  1780. with the compiled-in default environment - *silently*!!! [This is
  1781. necessary, because the first environment variable we need is the
  1782. "baudrate" setting for the console - if we have a bad CRC, we don't
  1783. have any device yet where we could complain.]
  1784. Note: once the monitor has been relocated, then it will complain if
  1785. the default environment is used; a new CRC is computed as soon as you
  1786. use the "saveenv" command to store a valid environment.
  1787. - CFG_FAULT_ECHO_LINK_DOWN:
  1788. Echo the inverted Ethernet link state to the fault LED.
  1789. Note: If this option is active, then CFG_FAULT_MII_ADDR
  1790. also needs to be defined.
  1791. - CFG_FAULT_MII_ADDR:
  1792. MII address of the PHY to check for the Ethernet link state.
  1793. - CFG_64BIT_VSPRINTF:
  1794. Makes vsprintf (and all *printf functions) support printing
  1795. of 64bit values by using the L quantifier
  1796. - CFG_64BIT_STRTOUL:
  1797. Adds simple_strtoull that returns a 64bit value
  1798. Low Level (hardware related) configuration options:
  1799. ---------------------------------------------------
  1800. - CFG_CACHELINE_SIZE:
  1801. Cache Line Size of the CPU.
  1802. - CFG_DEFAULT_IMMR:
  1803. Default address of the IMMR after system reset.
  1804. Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
  1805. and RPXsuper) to be able to adjust the position of
  1806. the IMMR register after a reset.
  1807. - Floppy Disk Support:
  1808. CFG_FDC_DRIVE_NUMBER
  1809. the default drive number (default value 0)
  1810. CFG_ISA_IO_STRIDE
  1811. defines the spacing between FDC chipset registers
  1812. (default value 1)
  1813. CFG_ISA_IO_OFFSET
  1814. defines the offset of register from address. It
  1815. depends on which part of the data bus is connected to
  1816. the FDC chipset. (default value 0)
  1817. If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and
  1818. CFG_FDC_DRIVE_NUMBER are undefined, they take their
  1819. default value.
  1820. if CFG_FDC_HW_INIT is defined, then the function
  1821. fdc_hw_init() is called at the beginning of the FDC
  1822. setup. fdc_hw_init() must be provided by the board
  1823. source code. It is used to make hardware dependant
  1824. initializations.
  1825. - CFG_IMMR: Physical address of the Internal Memory.
  1826. DO NOT CHANGE unless you know exactly what you're
  1827. doing! (11-4) [MPC8xx/82xx systems only]
  1828. - CFG_INIT_RAM_ADDR:
  1829. Start address of memory area that can be used for
  1830. initial data and stack; please note that this must be
  1831. writable memory that is working WITHOUT special
  1832. initialization, i. e. you CANNOT use normal RAM which
  1833. will become available only after programming the
  1834. memory controller and running certain initialization
  1835. sequences.
  1836. U-Boot uses the following memory types:
  1837. - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
  1838. - MPC824X: data cache
  1839. - PPC4xx: data cache
  1840. - CFG_GBL_DATA_OFFSET:
  1841. Offset of the initial data structure in the memory
  1842. area defined by CFG_INIT_RAM_ADDR. Usually
  1843. CFG_GBL_DATA_OFFSET is chosen such that the initial
  1844. data is located at the end of the available space
  1845. (sometimes written as (CFG_INIT_RAM_END -
  1846. CFG_INIT_DATA_SIZE), and the initial stack is just
  1847. below that area (growing from (CFG_INIT_RAM_ADDR +
  1848. CFG_GBL_DATA_OFFSET) downward.
  1849. Note:
  1850. On the MPC824X (or other systems that use the data
  1851. cache for initial memory) the address chosen for
  1852. CFG_INIT_RAM_ADDR is basically arbitrary - it must
  1853. point to an otherwise UNUSED address space between
  1854. the top of RAM and the start of the PCI space.
  1855. - CFG_SIUMCR: SIU Module Configuration (11-6)
  1856. - CFG_SYPCR: System Protection Control (11-9)
  1857. - CFG_TBSCR: Time Base Status and Control (11-26)
  1858. - CFG_PISCR: Periodic Interrupt Status and Control (11-31)
  1859. - CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
  1860. - CFG_SCCR: System Clock and reset Control Register (15-27)
  1861. - CFG_OR_TIMING_SDRAM:
  1862. SDRAM timing
  1863. - CFG_MAMR_PTA:
  1864. periodic timer for refresh
  1865. - CFG_DER: Debug Event Register (37-47)
  1866. - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM,
  1867. CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP,
  1868. CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM,
  1869. CFG_BR1_PRELIM:
  1870. Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
  1871. - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
  1872. CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM,
  1873. CFG_OR3_PRELIM, CFG_BR3_PRELIM:
  1874. Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
  1875. - CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K,
  1876. CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL:
  1877. Machine Mode Register and Memory Periodic Timer
  1878. Prescaler definitions (SDRAM timing)
  1879. - CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]:
  1880. enable I2C microcode relocation patch (MPC8xx);
  1881. define relocation offset in DPRAM [DSP2]
  1882. - CFG_SMC_UCODE_PATCH, CFG_SMC_DPMEM_OFFSET [0x1FC0]:
  1883. enable SMC microcode relocation patch (MPC8xx);
  1884. define relocation offset in DPRAM [SMC1]
  1885. - CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]:
  1886. enable SPI microcode relocation patch (MPC8xx);
  1887. define relocation offset in DPRAM [SCC4]
  1888. - CFG_USE_OSCCLK:
  1889. Use OSCM clock mode on MBX8xx board. Be careful,
  1890. wrong setting might damage your board. Read
  1891. doc/README.MBX before setting this variable!
  1892. - CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
  1893. Offset of the bootmode word in DPRAM used by post
  1894. (Power On Self Tests). This definition overrides
  1895. #define'd default value in commproc.h resp.
  1896. cpm_8260.h.
  1897. - CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB,
  1898. CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL,
  1899. CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS,
  1900. CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB,
  1901. CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
  1902. CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL,
  1903. CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE,
  1904. CFG_POCMR2_MASK_ATTRIB: (MPC826x only)
  1905. Overrides the default PCI memory map in cpu/mpc8260/pci.c if set.
  1906. - CONFIG_SPD_EEPROM
  1907. Get DDR timing information from an I2C EEPROM. Common
  1908. with pluggable memory modules such as SODIMMs
  1909. SPD_EEPROM_ADDRESS
  1910. I2C address of the SPD EEPROM
  1911. - CFG_SPD_BUS_NUM
  1912. If SPD EEPROM is on an I2C bus other than the first
  1913. one, specify here. Note that the value must resolve
  1914. to something your driver can deal with.
  1915. - CFG_83XX_DDR_USES_CS0
  1916. Only for 83xx systems. If specified, then DDR should
  1917. be configured using CS0 and CS1 instead of CS2 and CS3.
  1918. - CFG_83XX_DDR_USES_CS0
  1919. Only for 83xx systems. If specified, then DDR should
  1920. be configured using CS0 and CS1 instead of CS2 and CS3.
  1921. - CONFIG_ETHER_ON_FEC[12]
  1922. Define to enable FEC[12] on a 8xx series processor.
  1923. - CONFIG_FEC[12]_PHY
  1924. Define to the hardcoded PHY address which corresponds
  1925. to the given FEC; i. e.
  1926. #define CONFIG_FEC1_PHY 4
  1927. means that the PHY with address 4 is connected to FEC1
  1928. When set to -1, means to probe for first available.
  1929. - CONFIG_FEC[12]_PHY_NORXERR
  1930. The PHY does not have a RXERR line (RMII only).
  1931. (so program the FEC to ignore it).
  1932. - CONFIG_RMII
  1933. Enable RMII mode for all FECs.
  1934. Note that this is a global option, we can't
  1935. have one FEC in standard MII mode and another in RMII mode.
  1936. - CONFIG_CRC32_VERIFY
  1937. Add a verify option to the crc32 command.
  1938. The syntax is:
  1939. => crc32 -v <address> <count> <crc32>
  1940. Where address/count indicate a memory area
  1941. and crc32 is the correct crc32 which the
  1942. area should have.
  1943. - CONFIG_LOOPW
  1944. Add the "loopw" memory command. This only takes effect if
  1945. the memory commands are activated globally (CONFIG_CMD_MEM).
  1946. - CONFIG_MX_CYCLIC
  1947. Add the "mdc" and "mwc" memory commands. These are cyclic
  1948. "md/mw" commands.
  1949. Examples:
  1950. => mdc.b 10 4 500
  1951. This command will print 4 bytes (10,11,12,13) each 500 ms.
  1952. => mwc.l 100 12345678 10
  1953. This command will write 12345678 to address 100 all 10 ms.
  1954. This only takes effect if the memory commands are activated
  1955. globally (CONFIG_CMD_MEM).
  1956. - CONFIG_SKIP_LOWLEVEL_INIT
  1957. - CONFIG_SKIP_RELOCATE_UBOOT
  1958. [ARM only] If these variables are defined, then
  1959. certain low level initializations (like setting up
  1960. the memory controller) are omitted and/or U-Boot does
  1961. not relocate itself into RAM.
  1962. Normally these variables MUST NOT be defined. The
  1963. only exception is when U-Boot is loaded (to RAM) by
  1964. some other boot loader or by a debugger which
  1965. performs these initializations itself.
  1966. Building the Software:
  1967. ======================
  1968. Building U-Boot has been tested in several native build environments
  1969. and in many different cross environments. Of course we cannot support
  1970. all possibly existing versions of cross development tools in all
  1971. (potentially obsolete) versions. In case of tool chain problems we
  1972. recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
  1973. which is extensively used to build and test U-Boot.
  1974. If you are not using a native environment, it is assumed that you
  1975. have GNU cross compiling tools available in your path. In this case,
  1976. you must set the environment variable CROSS_COMPILE in your shell.
  1977. Note that no changes to the Makefile or any other source files are
  1978. necessary. For example using the ELDK on a 4xx CPU, please enter:
  1979. $ CROSS_COMPILE=ppc_4xx-
  1980. $ export CROSS_COMPILE
  1981. U-Boot is intended to be simple to build. After installing the
  1982. sources you must configure U-Boot for one specific board type. This
  1983. is done by typing:
  1984. make NAME_config
  1985. where "NAME_config" is the name of one of the existing configu-
  1986. rations; see the main Makefile for supported names.
  1987. Note: for some board special configuration names may exist; check if
  1988. additional information is available from the board vendor; for
  1989. instance, the TQM823L systems are available without (standard)
  1990. or with LCD support. You can select such additional "features"
  1991. when choosing the configuration, i. e.
  1992. make TQM823L_config
  1993. - will configure for a plain TQM823L, i. e. no LCD support
  1994. make TQM823L_LCD_config
  1995. - will configure for a TQM823L with U-Boot console on LCD
  1996. etc.
  1997. Finally, type "make all", and you should get some working U-Boot
  1998. images ready for download to / installation on your system:
  1999. - "u-boot.bin" is a raw binary image
  2000. - "u-boot" is an image in ELF binary format
  2001. - "u-boot.srec" is in Motorola S-Record format
  2002. By default the build is performed locally and the objects are saved
  2003. in the source directory. One of the two methods can be used to change
  2004. this behavior and build U-Boot to some external directory:
  2005. 1. Add O= to the make command line invocations:
  2006. make O=/tmp/build distclean
  2007. make O=/tmp/build NAME_config
  2008. make O=/tmp/build all
  2009. 2. Set environment variable BUILD_DIR to point to the desired location:
  2010. export BUILD_DIR=/tmp/build
  2011. make distclean
  2012. make NAME_config
  2013. make all
  2014. Note that the command line "O=" setting overrides the BUILD_DIR environment
  2015. variable.
  2016. Please be aware that the Makefiles assume you are using GNU make, so
  2017. for instance on NetBSD you might need to use "gmake" instead of
  2018. native "make".
  2019. If the system board that you have is not listed, then you will need
  2020. to port U-Boot to your hardware platform. To do this, follow these
  2021. steps:
  2022. 1. Add a new configuration option for your board to the toplevel
  2023. "Makefile" and to the "MAKEALL" script, using the existing
  2024. entries as examples. Note that here and at many other places
  2025. boards and other names are listed in alphabetical sort order. Please
  2026. keep this order.
  2027. 2. Create a new directory to hold your board specific code. Add any
  2028. files you need. In your board directory, you will need at least
  2029. the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
  2030. 3. Create a new configuration file "include/configs/<board>.h" for
  2031. your board
  2032. 3. If you're porting U-Boot to a new CPU, then also create a new
  2033. directory to hold your CPU specific code. Add any files you need.
  2034. 4. Run "make <board>_config" with your new name.
  2035. 5. Type "make", and you should get a working "u-boot.srec" file
  2036. to be installed on your target system.
  2037. 6. Debug and solve any problems that might arise.
  2038. [Of course, this last step is much harder than it sounds.]
  2039. Testing of U-Boot Modifications, Ports to New Hardware, etc.:
  2040. ==============================================================
  2041. If you have modified U-Boot sources (for instance added a new board
  2042. or support for new devices, a new CPU, etc.) you are expected to
  2043. provide feedback to the other developers. The feedback normally takes
  2044. the form of a "patch", i. e. a context diff against a certain (latest
  2045. official or latest in the git repository) version of U-Boot sources.
  2046. But before you submit such a patch, please verify that your modifi-
  2047. cation did not break existing code. At least make sure that *ALL* of
  2048. the supported boards compile WITHOUT ANY compiler warnings. To do so,
  2049. just run the "MAKEALL" script, which will configure and build U-Boot
  2050. for ALL supported system. Be warned, this will take a while. You can
  2051. select which (cross) compiler to use by passing a `CROSS_COMPILE'
  2052. environment variable to the script, i. e. to use the ELDK cross tools
  2053. you can type
  2054. CROSS_COMPILE=ppc_8xx- MAKEALL
  2055. or to build on a native PowerPC system you can type
  2056. CROSS_COMPILE=' ' MAKEALL
  2057. When using the MAKEALL script, the default behaviour is to build
  2058. U-Boot in the source directory. This location can be changed by
  2059. setting the BUILD_DIR environment variable. Also, for each target
  2060. built, the MAKEALL script saves two log files (<target>.ERR and
  2061. <target>.MAKEALL) in the <source dir>/LOG directory. This default
  2062. location can be changed by setting the MAKEALL_LOGDIR environment
  2063. variable. For example:
  2064. export BUILD_DIR=/tmp/build
  2065. export MAKEALL_LOGDIR=/tmp/log
  2066. CROSS_COMPILE=ppc_8xx- MAKEALL
  2067. With the above settings build objects are saved in the /tmp/build,
  2068. log files are saved in the /tmp/log and the source tree remains clean
  2069. during the whole build process.
  2070. See also "U-Boot Porting Guide" below.
  2071. Monitor Commands - Overview:
  2072. ============================
  2073. go - start application at address 'addr'
  2074. run - run commands in an environment variable
  2075. bootm - boot application image from memory
  2076. bootp - boot image via network using BootP/TFTP protocol
  2077. tftpboot- boot image via network using TFTP protocol
  2078. and env variables "ipaddr" and "serverip"
  2079. (and eventually "gatewayip")
  2080. rarpboot- boot image via network using RARP/TFTP protocol
  2081. diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
  2082. loads - load S-Record file over serial line
  2083. loadb - load binary file over serial line (kermit mode)
  2084. md - memory display
  2085. mm - memory modify (auto-incrementing)
  2086. nm - memory modify (constant address)
  2087. mw - memory write (fill)
  2088. cp - memory copy
  2089. cmp - memory compare
  2090. crc32 - checksum calculation
  2091. imd - i2c memory display
  2092. imm - i2c memory modify (auto-incrementing)
  2093. inm - i2c memory modify (constant address)
  2094. imw - i2c memory write (fill)
  2095. icrc32 - i2c checksum calculation
  2096. iprobe - probe to discover valid I2C chip addresses
  2097. iloop - infinite loop on address range
  2098. isdram - print SDRAM configuration information
  2099. sspi - SPI utility commands
  2100. base - print or set address offset
  2101. printenv- print environment variables
  2102. setenv - set environment variables
  2103. saveenv - save environment variables to persistent storage
  2104. protect - enable or disable FLASH write protection
  2105. erase - erase FLASH memory
  2106. flinfo - print FLASH memory information
  2107. bdinfo - print Board Info structure
  2108. iminfo - print header information for application image
  2109. coninfo - print console devices and informations
  2110. ide - IDE sub-system
  2111. loop - infinite loop on address range
  2112. loopw - infinite write loop on address range
  2113. mtest - simple RAM test
  2114. icache - enable or disable instruction cache
  2115. dcache - enable or disable data cache
  2116. reset - Perform RESET of the CPU
  2117. echo - echo args to console
  2118. version - print monitor version
  2119. help - print online help
  2120. ? - alias for 'help'
  2121. Monitor Commands - Detailed Description:
  2122. ========================================
  2123. TODO.
  2124. For now: just type "help <command>".
  2125. Environment Variables:
  2126. ======================
  2127. U-Boot supports user configuration using Environment Variables which
  2128. can be made persistent by saving to Flash memory.
  2129. Environment Variables are set using "setenv", printed using
  2130. "printenv", and saved to Flash using "saveenv". Using "setenv"
  2131. without a value can be used to delete a variable from the
  2132. environment. As long as you don't save the environment you are
  2133. working with an in-memory copy. In case the Flash area containing the
  2134. environment is erased by accident, a default environment is provided.
  2135. Some configuration options can be set using Environment Variables:
  2136. baudrate - see CONFIG_BAUDRATE
  2137. bootdelay - see CONFIG_BOOTDELAY
  2138. bootcmd - see CONFIG_BOOTCOMMAND
  2139. bootargs - Boot arguments when booting an RTOS image
  2140. bootfile - Name of the image to load with TFTP
  2141. bootm_low - Memory range available for image processing in the bootm
  2142. command can be restricted. This variable is given as
  2143. a hexadecimal number and defines lowest address allowed
  2144. for use by the bootm command. See also "bootm_size"
  2145. environment variable. Address defined by "bootm_low" is
  2146. also the base of the initial memory mapping for the Linux
  2147. kernel -- see the description of CFG_BOOTMAPSZ.
  2148. bootm_size - Memory range available for image processing in the bootm
  2149. command can be restricted. This variable is given as
  2150. a hexadecimal number and defines the size of the region
  2151. allowed for use by the bootm command. See also "bootm_low"
  2152. environment variable.
  2153. updatefile - Location of the software update file on a TFTP server, used
  2154. by the automatic software update feature. Please refer to
  2155. documentation in doc/README.update for more details.
  2156. autoload - if set to "no" (any string beginning with 'n'),
  2157. "bootp" will just load perform a lookup of the
  2158. configuration from the BOOTP server, but not try to
  2159. load any image using TFTP
  2160. autoscript - if set to "yes" commands like "loadb", "loady",
  2161. "bootp", "tftpb", "rarpboot" and "nfs" will attempt
  2162. to automatically run script images (by internally
  2163. calling "autoscript").
  2164. autoscript_uname - if script image is in a format (FIT) this
  2165. variable is used to get script subimage unit name.
  2166. autostart - if set to "yes", an image loaded using the "bootp",
  2167. "rarpboot", "tftpboot" or "diskboot" commands will
  2168. be automatically started (by internally calling
  2169. "bootm")
  2170. If set to "no", a standalone image passed to the
  2171. "bootm" command will be copied to the load address
  2172. (and eventually uncompressed), but NOT be started.
  2173. This can be used to load and uncompress arbitrary
  2174. data.
  2175. i2cfast - (PPC405GP|PPC405EP only)
  2176. if set to 'y' configures Linux I2C driver for fast
  2177. mode (400kHZ). This environment variable is used in
  2178. initialization code. So, for changes to be effective
  2179. it must be saved and board must be reset.
  2180. initrd_high - restrict positioning of initrd images:
  2181. If this variable is not set, initrd images will be
  2182. copied to the highest possible address in RAM; this
  2183. is usually what you want since it allows for
  2184. maximum initrd size. If for some reason you want to
  2185. make sure that the initrd image is loaded below the
  2186. CFG_BOOTMAPSZ limit, you can set this environment
  2187. variable to a value of "no" or "off" or "0".
  2188. Alternatively, you can set it to a maximum upper
  2189. address to use (U-Boot will still check that it
  2190. does not overwrite the U-Boot stack and data).
  2191. For instance, when you have a system with 16 MB
  2192. RAM, and want to reserve 4 MB from use by Linux,
  2193. you can do this by adding "mem=12M" to the value of
  2194. the "bootargs" variable. However, now you must make
  2195. sure that the initrd image is placed in the first
  2196. 12 MB as well - this can be done with
  2197. setenv initrd_high 00c00000
  2198. If you set initrd_high to 0xFFFFFFFF, this is an
  2199. indication to U-Boot that all addresses are legal
  2200. for the Linux kernel, including addresses in flash
  2201. memory. In this case U-Boot will NOT COPY the
  2202. ramdisk at all. This may be useful to reduce the
  2203. boot time on your system, but requires that this
  2204. feature is supported by your Linux kernel.
  2205. ipaddr - IP address; needed for tftpboot command
  2206. loadaddr - Default load address for commands like "bootp",
  2207. "rarpboot", "tftpboot", "loadb" or "diskboot"
  2208. loads_echo - see CONFIG_LOADS_ECHO
  2209. serverip - TFTP server IP address; needed for tftpboot command
  2210. bootretry - see CONFIG_BOOT_RETRY_TIME
  2211. bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
  2212. bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
  2213. ethprime - When CONFIG_NET_MULTI is enabled controls which
  2214. interface is used first.
  2215. ethact - When CONFIG_NET_MULTI is enabled controls which
  2216. interface is currently active. For example you
  2217. can do the following
  2218. => setenv ethact FEC ETHERNET
  2219. => ping 192.168.0.1 # traffic sent on FEC ETHERNET
  2220. => setenv ethact SCC ETHERNET
  2221. => ping 10.0.0.1 # traffic sent on SCC ETHERNET
  2222. ethrotate - When set to "no" U-Boot does not go through all
  2223. available network interfaces.
  2224. It just stays at the currently selected interface.
  2225. netretry - When set to "no" each network operation will
  2226. either succeed or fail without retrying.
  2227. When set to "once" the network operation will
  2228. fail when all the available network interfaces
  2229. are tried once without success.
  2230. Useful on scripts which control the retry operation
  2231. themselves.
  2232. npe_ucode - see CONFIG_IXP4XX_NPE_EXT_UCOD
  2233. if set load address for the NPE microcode
  2234. tftpsrcport - If this is set, the value is used for TFTP's
  2235. UDP source port.
  2236. tftpdstport - If this is set, the value is used for TFTP's UDP
  2237. destination port instead of the Well Know Port 69.
  2238. vlan - When set to a value < 4095 the traffic over
  2239. Ethernet is encapsulated/received over 802.1q
  2240. VLAN tagged frames.
  2241. The following environment variables may be used and automatically
  2242. updated by the network boot commands ("bootp" and "rarpboot"),
  2243. depending the information provided by your boot server:
  2244. bootfile - see above
  2245. dnsip - IP address of your Domain Name Server
  2246. dnsip2 - IP address of your secondary Domain Name Server
  2247. gatewayip - IP address of the Gateway (Router) to use
  2248. hostname - Target hostname
  2249. ipaddr - see above
  2250. netmask - Subnet Mask
  2251. rootpath - Pathname of the root filesystem on the NFS server
  2252. serverip - see above
  2253. There are two special Environment Variables:
  2254. serial# - contains hardware identification information such
  2255. as type string and/or serial number
  2256. ethaddr - Ethernet address
  2257. These variables can be set only once (usually during manufacturing of
  2258. the board). U-Boot refuses to delete or overwrite these variables
  2259. once they have been set once.
  2260. Further special Environment Variables:
  2261. ver - Contains the U-Boot version string as printed
  2262. with the "version" command. This variable is
  2263. readonly (see CONFIG_VERSION_VARIABLE).
  2264. Please note that changes to some configuration parameters may take
  2265. only effect after the next boot (yes, that's just like Windoze :-).
  2266. Command Line Parsing:
  2267. =====================
  2268. There are two different command line parsers available with U-Boot:
  2269. the old "simple" one, and the much more powerful "hush" shell:
  2270. Old, simple command line parser:
  2271. --------------------------------
  2272. - supports environment variables (through setenv / saveenv commands)
  2273. - several commands on one line, separated by ';'
  2274. - variable substitution using "... ${name} ..." syntax
  2275. - special characters ('$', ';') can be escaped by prefixing with '\',
  2276. for example:
  2277. setenv bootcmd bootm \${address}
  2278. - You can also escape text by enclosing in single apostrophes, for example:
  2279. setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
  2280. Hush shell:
  2281. -----------
  2282. - similar to Bourne shell, with control structures like
  2283. if...then...else...fi, for...do...done; while...do...done,
  2284. until...do...done, ...
  2285. - supports environment ("global") variables (through setenv / saveenv
  2286. commands) and local shell variables (through standard shell syntax
  2287. "name=value"); only environment variables can be used with "run"
  2288. command
  2289. General rules:
  2290. --------------
  2291. (1) If a command line (or an environment variable executed by a "run"
  2292. command) contains several commands separated by semicolon, and
  2293. one of these commands fails, then the remaining commands will be
  2294. executed anyway.
  2295. (2) If you execute several variables with one call to run (i. e.
  2296. calling run with a list of variables as arguments), any failing
  2297. command will cause "run" to terminate, i. e. the remaining
  2298. variables are not executed.
  2299. Note for Redundant Ethernet Interfaces:
  2300. =======================================
  2301. Some boards come with redundant Ethernet interfaces; U-Boot supports
  2302. such configurations and is capable of automatic selection of a
  2303. "working" interface when needed. MAC assignment works as follows:
  2304. Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
  2305. MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
  2306. "eth1addr" (=>eth1), "eth2addr", ...
  2307. If the network interface stores some valid MAC address (for instance
  2308. in SROM), this is used as default address if there is NO correspon-
  2309. ding setting in the environment; if the corresponding environment
  2310. variable is set, this overrides the settings in the card; that means:
  2311. o If the SROM has a valid MAC address, and there is no address in the
  2312. environment, the SROM's address is used.
  2313. o If there is no valid address in the SROM, and a definition in the
  2314. environment exists, then the value from the environment variable is
  2315. used.
  2316. o If both the SROM and the environment contain a MAC address, and
  2317. both addresses are the same, this MAC address is used.
  2318. o If both the SROM and the environment contain a MAC address, and the
  2319. addresses differ, the value from the environment is used and a
  2320. warning is printed.
  2321. o If neither SROM nor the environment contain a MAC address, an error
  2322. is raised.
  2323. Image Formats:
  2324. ==============
  2325. U-Boot is capable of booting (and performing other auxiliary operations on)
  2326. images in two formats:
  2327. New uImage format (FIT)
  2328. -----------------------
  2329. Flexible and powerful format based on Flattened Image Tree -- FIT (similar
  2330. to Flattened Device Tree). It allows the use of images with multiple
  2331. components (several kernels, ramdisks, etc.), with contents protected by
  2332. SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
  2333. Old uImage format
  2334. -----------------
  2335. Old image format is based on binary files which can be basically anything,
  2336. preceded by a special header; see the definitions in include/image.h for
  2337. details; basically, the header defines the following image properties:
  2338. * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
  2339. 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
  2340. LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
  2341. Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
  2342. INTEGRITY).
  2343. * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
  2344. IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
  2345. Currently supported: ARM, AVR32, Intel x86, MIPS, NIOS, PowerPC).
  2346. * Compression Type (uncompressed, gzip, bzip2)
  2347. * Load Address
  2348. * Entry Point
  2349. * Image Name
  2350. * Image Timestamp
  2351. The header is marked by a special Magic Number, and both the header
  2352. and the data portions of the image are secured against corruption by
  2353. CRC32 checksums.
  2354. Linux Support:
  2355. ==============
  2356. Although U-Boot should support any OS or standalone application
  2357. easily, the main focus has always been on Linux during the design of
  2358. U-Boot.
  2359. U-Boot includes many features that so far have been part of some
  2360. special "boot loader" code within the Linux kernel. Also, any
  2361. "initrd" images to be used are no longer part of one big Linux image;
  2362. instead, kernel and "initrd" are separate images. This implementation
  2363. serves several purposes:
  2364. - the same features can be used for other OS or standalone
  2365. applications (for instance: using compressed images to reduce the
  2366. Flash memory footprint)
  2367. - it becomes much easier to port new Linux kernel versions because
  2368. lots of low-level, hardware dependent stuff are done by U-Boot
  2369. - the same Linux kernel image can now be used with different "initrd"
  2370. images; of course this also means that different kernel images can
  2371. be run with the same "initrd". This makes testing easier (you don't
  2372. have to build a new "zImage.initrd" Linux image when you just
  2373. change a file in your "initrd"). Also, a field-upgrade of the
  2374. software is easier now.
  2375. Linux HOWTO:
  2376. ============
  2377. Porting Linux to U-Boot based systems:
  2378. ---------------------------------------
  2379. U-Boot cannot save you from doing all the necessary modifications to
  2380. configure the Linux device drivers for use with your target hardware
  2381. (no, we don't intend to provide a full virtual machine interface to
  2382. Linux :-).
  2383. But now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
  2384. Just make sure your machine specific header file (for instance
  2385. include/asm-ppc/tqm8xx.h) includes the same definition of the Board
  2386. Information structure as we define in include/asm-<arch>/u-boot.h,
  2387. and make sure that your definition of IMAP_ADDR uses the same value
  2388. as your U-Boot configuration in CFG_IMMR.
  2389. Configuring the Linux kernel:
  2390. -----------------------------
  2391. No specific requirements for U-Boot. Make sure you have some root
  2392. device (initial ramdisk, NFS) for your target system.
  2393. Building a Linux Image:
  2394. -----------------------
  2395. With U-Boot, "normal" build targets like "zImage" or "bzImage" are
  2396. not used. If you use recent kernel source, a new build target
  2397. "uImage" will exist which automatically builds an image usable by
  2398. U-Boot. Most older kernels also have support for a "pImage" target,
  2399. which was introduced for our predecessor project PPCBoot and uses a
  2400. 100% compatible format.
  2401. Example:
  2402. make TQM850L_config
  2403. make oldconfig
  2404. make dep
  2405. make uImage
  2406. The "uImage" build target uses a special tool (in 'tools/mkimage') to
  2407. encapsulate a compressed Linux kernel image with header information,
  2408. CRC32 checksum etc. for use with U-Boot. This is what we are doing:
  2409. * build a standard "vmlinux" kernel image (in ELF binary format):
  2410. * convert the kernel into a raw binary image:
  2411. ${CROSS_COMPILE}-objcopy -O binary \
  2412. -R .note -R .comment \
  2413. -S vmlinux linux.bin
  2414. * compress the binary image:
  2415. gzip -9 linux.bin
  2416. * package compressed binary image for U-Boot:
  2417. mkimage -A ppc -O linux -T kernel -C gzip \
  2418. -a 0 -e 0 -n "Linux Kernel Image" \
  2419. -d linux.bin.gz uImage
  2420. The "mkimage" tool can also be used to create ramdisk images for use
  2421. with U-Boot, either separated from the Linux kernel image, or
  2422. combined into one file. "mkimage" encapsulates the images with a 64
  2423. byte header containing information about target architecture,
  2424. operating system, image type, compression method, entry points, time
  2425. stamp, CRC32 checksums, etc.
  2426. "mkimage" can be called in two ways: to verify existing images and
  2427. print the header information, or to build new images.
  2428. In the first form (with "-l" option) mkimage lists the information
  2429. contained in the header of an existing U-Boot image; this includes
  2430. checksum verification:
  2431. tools/mkimage -l image
  2432. -l ==> list image header information
  2433. The second form (with "-d" option) is used to build a U-Boot image
  2434. from a "data file" which is used as image payload:
  2435. tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
  2436. -n name -d data_file image
  2437. -A ==> set architecture to 'arch'
  2438. -O ==> set operating system to 'os'
  2439. -T ==> set image type to 'type'
  2440. -C ==> set compression type 'comp'
  2441. -a ==> set load address to 'addr' (hex)
  2442. -e ==> set entry point to 'ep' (hex)
  2443. -n ==> set image name to 'name'
  2444. -d ==> use image data from 'datafile'
  2445. Right now, all Linux kernels for PowerPC systems use the same load
  2446. address (0x00000000), but the entry point address depends on the
  2447. kernel version:
  2448. - 2.2.x kernels have the entry point at 0x0000000C,
  2449. - 2.3.x and later kernels have the entry point at 0x00000000.
  2450. So a typical call to build a U-Boot image would read:
  2451. -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
  2452. > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
  2453. > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
  2454. > examples/uImage.TQM850L
  2455. Image Name: 2.4.4 kernel for TQM850L
  2456. Created: Wed Jul 19 02:34:59 2000
  2457. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  2458. Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
  2459. Load Address: 0x00000000
  2460. Entry Point: 0x00000000
  2461. To verify the contents of the image (or check for corruption):
  2462. -> tools/mkimage -l examples/uImage.TQM850L
  2463. Image Name: 2.4.4 kernel for TQM850L
  2464. Created: Wed Jul 19 02:34:59 2000
  2465. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  2466. Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
  2467. Load Address: 0x00000000
  2468. Entry Point: 0x00000000
  2469. NOTE: for embedded systems where boot time is critical you can trade
  2470. speed for memory and install an UNCOMPRESSED image instead: this
  2471. needs more space in Flash, but boots much faster since it does not
  2472. need to be uncompressed:
  2473. -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
  2474. -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
  2475. > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
  2476. > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
  2477. > examples/uImage.TQM850L-uncompressed
  2478. Image Name: 2.4.4 kernel for TQM850L
  2479. Created: Wed Jul 19 02:34:59 2000
  2480. Image Type: PowerPC Linux Kernel Image (uncompressed)
  2481. Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
  2482. Load Address: 0x00000000
  2483. Entry Point: 0x00000000
  2484. Similar you can build U-Boot images from a 'ramdisk.image.gz' file
  2485. when your kernel is intended to use an initial ramdisk:
  2486. -> tools/mkimage -n 'Simple Ramdisk Image' \
  2487. > -A ppc -O linux -T ramdisk -C gzip \
  2488. > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
  2489. Image Name: Simple Ramdisk Image
  2490. Created: Wed Jan 12 14:01:50 2000
  2491. Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
  2492. Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
  2493. Load Address: 0x00000000
  2494. Entry Point: 0x00000000
  2495. Installing a Linux Image:
  2496. -------------------------
  2497. To downloading a U-Boot image over the serial (console) interface,
  2498. you must convert the image to S-Record format:
  2499. objcopy -I binary -O srec examples/image examples/image.srec
  2500. The 'objcopy' does not understand the information in the U-Boot
  2501. image header, so the resulting S-Record file will be relative to
  2502. address 0x00000000. To load it to a given address, you need to
  2503. specify the target address as 'offset' parameter with the 'loads'
  2504. command.
  2505. Example: install the image to address 0x40100000 (which on the
  2506. TQM8xxL is in the first Flash bank):
  2507. => erase 40100000 401FFFFF
  2508. .......... done
  2509. Erased 8 sectors
  2510. => loads 40100000
  2511. ## Ready for S-Record download ...
  2512. ~>examples/image.srec
  2513. 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
  2514. ...
  2515. 15989 15990 15991 15992
  2516. [file transfer complete]
  2517. [connected]
  2518. ## Start Addr = 0x00000000
  2519. You can check the success of the download using the 'iminfo' command;
  2520. this includes a checksum verification so you can be sure no data
  2521. corruption happened:
  2522. => imi 40100000
  2523. ## Checking Image at 40100000 ...
  2524. Image Name: 2.2.13 for initrd on TQM850L
  2525. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  2526. Data Size: 335725 Bytes = 327 kB = 0 MB
  2527. Load Address: 00000000
  2528. Entry Point: 0000000c
  2529. Verifying Checksum ... OK
  2530. Boot Linux:
  2531. -----------
  2532. The "bootm" command is used to boot an application that is stored in
  2533. memory (RAM or Flash). In case of a Linux kernel image, the contents
  2534. of the "bootargs" environment variable is passed to the kernel as
  2535. parameters. You can check and modify this variable using the
  2536. "printenv" and "setenv" commands:
  2537. => printenv bootargs
  2538. bootargs=root=/dev/ram
  2539. => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
  2540. => printenv bootargs
  2541. bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
  2542. => bootm 40020000
  2543. ## Booting Linux kernel at 40020000 ...
  2544. Image Name: 2.2.13 for NFS on TQM850L
  2545. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  2546. Data Size: 381681 Bytes = 372 kB = 0 MB
  2547. Load Address: 00000000
  2548. Entry Point: 0000000c
  2549. Verifying Checksum ... OK
  2550. Uncompressing Kernel Image ... OK
  2551. 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
  2552. Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
  2553. time_init: decrementer frequency = 187500000/60
  2554. Calibrating delay loop... 49.77 BogoMIPS
  2555. Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
  2556. ...
  2557. If you want to boot a Linux kernel with initial RAM disk, you pass
  2558. the memory addresses of both the kernel and the initrd image (PPBCOOT
  2559. format!) to the "bootm" command:
  2560. => imi 40100000 40200000
  2561. ## Checking Image at 40100000 ...
  2562. Image Name: 2.2.13 for initrd on TQM850L
  2563. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  2564. Data Size: 335725 Bytes = 327 kB = 0 MB
  2565. Load Address: 00000000
  2566. Entry Point: 0000000c
  2567. Verifying Checksum ... OK
  2568. ## Checking Image at 40200000 ...
  2569. Image Name: Simple Ramdisk Image
  2570. Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
  2571. Data Size: 566530 Bytes = 553 kB = 0 MB
  2572. Load Address: 00000000
  2573. Entry Point: 00000000
  2574. Verifying Checksum ... OK
  2575. => bootm 40100000 40200000
  2576. ## Booting Linux kernel at 40100000 ...
  2577. Image Name: 2.2.13 for initrd on TQM850L
  2578. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  2579. Data Size: 335725 Bytes = 327 kB = 0 MB
  2580. Load Address: 00000000
  2581. Entry Point: 0000000c
  2582. Verifying Checksum ... OK
  2583. Uncompressing Kernel Image ... OK
  2584. ## Loading RAMDisk Image at 40200000 ...
  2585. Image Name: Simple Ramdisk Image
  2586. Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
  2587. Data Size: 566530 Bytes = 553 kB = 0 MB
  2588. Load Address: 00000000
  2589. Entry Point: 00000000
  2590. Verifying Checksum ... OK
  2591. Loading Ramdisk ... OK
  2592. 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
  2593. Boot arguments: root=/dev/ram
  2594. time_init: decrementer frequency = 187500000/60
  2595. Calibrating delay loop... 49.77 BogoMIPS
  2596. ...
  2597. RAMDISK: Compressed image found at block 0
  2598. VFS: Mounted root (ext2 filesystem).
  2599. bash#
  2600. Boot Linux and pass a flat device tree:
  2601. -----------
  2602. First, U-Boot must be compiled with the appropriate defines. See the section
  2603. titled "Linux Kernel Interface" above for a more in depth explanation. The
  2604. following is an example of how to start a kernel and pass an updated
  2605. flat device tree:
  2606. => print oftaddr
  2607. oftaddr=0x300000
  2608. => print oft
  2609. oft=oftrees/mpc8540ads.dtb
  2610. => tftp $oftaddr $oft
  2611. Speed: 1000, full duplex
  2612. Using TSEC0 device
  2613. TFTP from server 192.168.1.1; our IP address is 192.168.1.101
  2614. Filename 'oftrees/mpc8540ads.dtb'.
  2615. Load address: 0x300000
  2616. Loading: #
  2617. done
  2618. Bytes transferred = 4106 (100a hex)
  2619. => tftp $loadaddr $bootfile
  2620. Speed: 1000, full duplex
  2621. Using TSEC0 device
  2622. TFTP from server 192.168.1.1; our IP address is 192.168.1.2
  2623. Filename 'uImage'.
  2624. Load address: 0x200000
  2625. Loading:############
  2626. done
  2627. Bytes transferred = 1029407 (fb51f hex)
  2628. => print loadaddr
  2629. loadaddr=200000
  2630. => print oftaddr
  2631. oftaddr=0x300000
  2632. => bootm $loadaddr - $oftaddr
  2633. ## Booting image at 00200000 ...
  2634. Image Name: Linux-2.6.17-dirty
  2635. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  2636. Data Size: 1029343 Bytes = 1005.2 kB
  2637. Load Address: 00000000
  2638. Entry Point: 00000000
  2639. Verifying Checksum ... OK
  2640. Uncompressing Kernel Image ... OK
  2641. Booting using flat device tree at 0x300000
  2642. Using MPC85xx ADS machine description
  2643. Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
  2644. [snip]
  2645. More About U-Boot Image Types:
  2646. ------------------------------
  2647. U-Boot supports the following image types:
  2648. "Standalone Programs" are directly runnable in the environment
  2649. provided by U-Boot; it is expected that (if they behave
  2650. well) you can continue to work in U-Boot after return from
  2651. the Standalone Program.
  2652. "OS Kernel Images" are usually images of some Embedded OS which
  2653. will take over control completely. Usually these programs
  2654. will install their own set of exception handlers, device
  2655. drivers, set up the MMU, etc. - this means, that you cannot
  2656. expect to re-enter U-Boot except by resetting the CPU.
  2657. "RAMDisk Images" are more or less just data blocks, and their
  2658. parameters (address, size) are passed to an OS kernel that is
  2659. being started.
  2660. "Multi-File Images" contain several images, typically an OS
  2661. (Linux) kernel image and one or more data images like
  2662. RAMDisks. This construct is useful for instance when you want
  2663. to boot over the network using BOOTP etc., where the boot
  2664. server provides just a single image file, but you want to get
  2665. for instance an OS kernel and a RAMDisk image.
  2666. "Multi-File Images" start with a list of image sizes, each
  2667. image size (in bytes) specified by an "uint32_t" in network
  2668. byte order. This list is terminated by an "(uint32_t)0".
  2669. Immediately after the terminating 0 follow the images, one by
  2670. one, all aligned on "uint32_t" boundaries (size rounded up to
  2671. a multiple of 4 bytes).
  2672. "Firmware Images" are binary images containing firmware (like
  2673. U-Boot or FPGA images) which usually will be programmed to
  2674. flash memory.
  2675. "Script files" are command sequences that will be executed by
  2676. U-Boot's command interpreter; this feature is especially
  2677. useful when you configure U-Boot to use a real shell (hush)
  2678. as command interpreter.
  2679. Standalone HOWTO:
  2680. =================
  2681. One of the features of U-Boot is that you can dynamically load and
  2682. run "standalone" applications, which can use some resources of
  2683. U-Boot like console I/O functions or interrupt services.
  2684. Two simple examples are included with the sources:
  2685. "Hello World" Demo:
  2686. -------------------
  2687. 'examples/hello_world.c' contains a small "Hello World" Demo
  2688. application; it is automatically compiled when you build U-Boot.
  2689. It's configured to run at address 0x00040004, so you can play with it
  2690. like that:
  2691. => loads
  2692. ## Ready for S-Record download ...
  2693. ~>examples/hello_world.srec
  2694. 1 2 3 4 5 6 7 8 9 10 11 ...
  2695. [file transfer complete]
  2696. [connected]
  2697. ## Start Addr = 0x00040004
  2698. => go 40004 Hello World! This is a test.
  2699. ## Starting application at 0x00040004 ...
  2700. Hello World
  2701. argc = 7
  2702. argv[0] = "40004"
  2703. argv[1] = "Hello"
  2704. argv[2] = "World!"
  2705. argv[3] = "This"
  2706. argv[4] = "is"
  2707. argv[5] = "a"
  2708. argv[6] = "test."
  2709. argv[7] = "<NULL>"
  2710. Hit any key to exit ...
  2711. ## Application terminated, rc = 0x0
  2712. Another example, which demonstrates how to register a CPM interrupt
  2713. handler with the U-Boot code, can be found in 'examples/timer.c'.
  2714. Here, a CPM timer is set up to generate an interrupt every second.
  2715. The interrupt service routine is trivial, just printing a '.'
  2716. character, but this is just a demo program. The application can be
  2717. controlled by the following keys:
  2718. ? - print current values og the CPM Timer registers
  2719. b - enable interrupts and start timer
  2720. e - stop timer and disable interrupts
  2721. q - quit application
  2722. => loads
  2723. ## Ready for S-Record download ...
  2724. ~>examples/timer.srec
  2725. 1 2 3 4 5 6 7 8 9 10 11 ...
  2726. [file transfer complete]
  2727. [connected]
  2728. ## Start Addr = 0x00040004
  2729. => go 40004
  2730. ## Starting application at 0x00040004 ...
  2731. TIMERS=0xfff00980
  2732. Using timer 1
  2733. tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
  2734. Hit 'b':
  2735. [q, b, e, ?] Set interval 1000000 us
  2736. Enabling timer
  2737. Hit '?':
  2738. [q, b, e, ?] ........
  2739. tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
  2740. Hit '?':
  2741. [q, b, e, ?] .
  2742. tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
  2743. Hit '?':
  2744. [q, b, e, ?] .
  2745. tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
  2746. Hit '?':
  2747. [q, b, e, ?] .
  2748. tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
  2749. Hit 'e':
  2750. [q, b, e, ?] ...Stopping timer
  2751. Hit 'q':
  2752. [q, b, e, ?] ## Application terminated, rc = 0x0
  2753. Minicom warning:
  2754. ================
  2755. Over time, many people have reported problems when trying to use the
  2756. "minicom" terminal emulation program for serial download. I (wd)
  2757. consider minicom to be broken, and recommend not to use it. Under
  2758. Unix, I recommend to use C-Kermit for general purpose use (and
  2759. especially for kermit binary protocol download ("loadb" command), and
  2760. use "cu" for S-Record download ("loads" command).
  2761. Nevertheless, if you absolutely want to use it try adding this
  2762. configuration to your "File transfer protocols" section:
  2763. Name Program Name U/D FullScr IO-Red. Multi
  2764. X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
  2765. Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
  2766. NetBSD Notes:
  2767. =============
  2768. Starting at version 0.9.2, U-Boot supports NetBSD both as host
  2769. (build U-Boot) and target system (boots NetBSD/mpc8xx).
  2770. Building requires a cross environment; it is known to work on
  2771. NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
  2772. need gmake since the Makefiles are not compatible with BSD make).
  2773. Note that the cross-powerpc package does not install include files;
  2774. attempting to build U-Boot will fail because <machine/ansi.h> is
  2775. missing. This file has to be installed and patched manually:
  2776. # cd /usr/pkg/cross/powerpc-netbsd/include
  2777. # mkdir powerpc
  2778. # ln -s powerpc machine
  2779. # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
  2780. # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
  2781. Native builds *don't* work due to incompatibilities between native
  2782. and U-Boot include files.
  2783. Booting assumes that (the first part of) the image booted is a
  2784. stage-2 loader which in turn loads and then invokes the kernel
  2785. proper. Loader sources will eventually appear in the NetBSD source
  2786. tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
  2787. meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
  2788. Implementation Internals:
  2789. =========================
  2790. The following is not intended to be a complete description of every
  2791. implementation detail. However, it should help to understand the
  2792. inner workings of U-Boot and make it easier to port it to custom
  2793. hardware.
  2794. Initial Stack, Global Data:
  2795. ---------------------------
  2796. The implementation of U-Boot is complicated by the fact that U-Boot
  2797. starts running out of ROM (flash memory), usually without access to
  2798. system RAM (because the memory controller is not initialized yet).
  2799. This means that we don't have writable Data or BSS segments, and BSS
  2800. is not initialized as zero. To be able to get a C environment working
  2801. at all, we have to allocate at least a minimal stack. Implementation
  2802. options for this are defined and restricted by the CPU used: Some CPU
  2803. models provide on-chip memory (like the IMMR area on MPC8xx and
  2804. MPC826x processors), on others (parts of) the data cache can be
  2805. locked as (mis-) used as memory, etc.
  2806. Chris Hallinan posted a good summary of these issues to the
  2807. u-boot-users mailing list:
  2808. Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
  2809. From: "Chris Hallinan" <clh@net1plus.com>
  2810. Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
  2811. ...
  2812. Correct me if I'm wrong, folks, but the way I understand it
  2813. is this: Using DCACHE as initial RAM for Stack, etc, does not
  2814. require any physical RAM backing up the cache. The cleverness
  2815. is that the cache is being used as a temporary supply of
  2816. necessary storage before the SDRAM controller is setup. It's
  2817. beyond the scope of this list to explain the details, but you
  2818. can see how this works by studying the cache architecture and
  2819. operation in the architecture and processor-specific manuals.
  2820. OCM is On Chip Memory, which I believe the 405GP has 4K. It
  2821. is another option for the system designer to use as an
  2822. initial stack/RAM area prior to SDRAM being available. Either
  2823. option should work for you. Using CS 4 should be fine if your
  2824. board designers haven't used it for something that would
  2825. cause you grief during the initial boot! It is frequently not
  2826. used.
  2827. CFG_INIT_RAM_ADDR should be somewhere that won't interfere
  2828. with your processor/board/system design. The default value
  2829. you will find in any recent u-boot distribution in
  2830. walnut.h should work for you. I'd set it to a value larger
  2831. than your SDRAM module. If you have a 64MB SDRAM module, set
  2832. it above 400_0000. Just make sure your board has no resources
  2833. that are supposed to respond to that address! That code in
  2834. start.S has been around a while and should work as is when
  2835. you get the config right.
  2836. -Chris Hallinan
  2837. DS4.COM, Inc.
  2838. It is essential to remember this, since it has some impact on the C
  2839. code for the initialization procedures:
  2840. * Initialized global data (data segment) is read-only. Do not attempt
  2841. to write it.
  2842. * Do not use any uninitialized global data (or implicitely initialized
  2843. as zero data - BSS segment) at all - this is undefined, initiali-
  2844. zation is performed later (when relocating to RAM).
  2845. * Stack space is very limited. Avoid big data buffers or things like
  2846. that.
  2847. Having only the stack as writable memory limits means we cannot use
  2848. normal global data to share information beween the code. But it
  2849. turned out that the implementation of U-Boot can be greatly
  2850. simplified by making a global data structure (gd_t) available to all
  2851. functions. We could pass a pointer to this data as argument to _all_
  2852. functions, but this would bloat the code. Instead we use a feature of
  2853. the GCC compiler (Global Register Variables) to share the data: we
  2854. place a pointer (gd) to the global data into a register which we
  2855. reserve for this purpose.
  2856. When choosing a register for such a purpose we are restricted by the
  2857. relevant (E)ABI specifications for the current architecture, and by
  2858. GCC's implementation.
  2859. For PowerPC, the following registers have specific use:
  2860. R1: stack pointer
  2861. R2: reserved for system use
  2862. R3-R4: parameter passing and return values
  2863. R5-R10: parameter passing
  2864. R13: small data area pointer
  2865. R30: GOT pointer
  2866. R31: frame pointer
  2867. (U-Boot also uses R14 as internal GOT pointer.)
  2868. ==> U-Boot will use R2 to hold a pointer to the global data
  2869. Note: on PPC, we could use a static initializer (since the
  2870. address of the global data structure is known at compile time),
  2871. but it turned out that reserving a register results in somewhat
  2872. smaller code - although the code savings are not that big (on
  2873. average for all boards 752 bytes for the whole U-Boot image,
  2874. 624 text + 127 data).
  2875. On Blackfin, the normal C ABI (except for P5) is followed as documented here:
  2876. http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
  2877. ==> U-Boot will use P5 to hold a pointer to the global data
  2878. On ARM, the following registers are used:
  2879. R0: function argument word/integer result
  2880. R1-R3: function argument word
  2881. R9: GOT pointer
  2882. R10: stack limit (used only if stack checking if enabled)
  2883. R11: argument (frame) pointer
  2884. R12: temporary workspace
  2885. R13: stack pointer
  2886. R14: link register
  2887. R15: program counter
  2888. ==> U-Boot will use R8 to hold a pointer to the global data
  2889. NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
  2890. or current versions of GCC may "optimize" the code too much.
  2891. Memory Management:
  2892. ------------------
  2893. U-Boot runs in system state and uses physical addresses, i.e. the
  2894. MMU is not used either for address mapping nor for memory protection.
  2895. The available memory is mapped to fixed addresses using the memory
  2896. controller. In this process, a contiguous block is formed for each
  2897. memory type (Flash, SDRAM, SRAM), even when it consists of several
  2898. physical memory banks.
  2899. U-Boot is installed in the first 128 kB of the first Flash bank (on
  2900. TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
  2901. booting and sizing and initializing DRAM, the code relocates itself
  2902. to the upper end of DRAM. Immediately below the U-Boot code some
  2903. memory is reserved for use by malloc() [see CFG_MALLOC_LEN
  2904. configuration setting]. Below that, a structure with global Board
  2905. Info data is placed, followed by the stack (growing downward).
  2906. Additionally, some exception handler code is copied to the low 8 kB
  2907. of DRAM (0x00000000 ... 0x00001FFF).
  2908. So a typical memory configuration with 16 MB of DRAM could look like
  2909. this:
  2910. 0x0000 0000 Exception Vector code
  2911. :
  2912. 0x0000 1FFF
  2913. 0x0000 2000 Free for Application Use
  2914. :
  2915. :
  2916. :
  2917. :
  2918. 0x00FB FF20 Monitor Stack (Growing downward)
  2919. 0x00FB FFAC Board Info Data and permanent copy of global data
  2920. 0x00FC 0000 Malloc Arena
  2921. :
  2922. 0x00FD FFFF
  2923. 0x00FE 0000 RAM Copy of Monitor Code
  2924. ... eventually: LCD or video framebuffer
  2925. ... eventually: pRAM (Protected RAM - unchanged by reset)
  2926. 0x00FF FFFF [End of RAM]
  2927. System Initialization:
  2928. ----------------------
  2929. In the reset configuration, U-Boot starts at the reset entry point
  2930. (on most PowerPC systems at address 0x00000100). Because of the reset
  2931. configuration for CS0# this is a mirror of the onboard Flash memory.
  2932. To be able to re-map memory U-Boot then jumps to its link address.
  2933. To be able to implement the initialization code in C, a (small!)
  2934. initial stack is set up in the internal Dual Ported RAM (in case CPUs
  2935. which provide such a feature like MPC8xx or MPC8260), or in a locked
  2936. part of the data cache. After that, U-Boot initializes the CPU core,
  2937. the caches and the SIU.
  2938. Next, all (potentially) available memory banks are mapped using a
  2939. preliminary mapping. For example, we put them on 512 MB boundaries
  2940. (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
  2941. on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
  2942. programmed for SDRAM access. Using the temporary configuration, a
  2943. simple memory test is run that determines the size of the SDRAM
  2944. banks.
  2945. When there is more than one SDRAM bank, and the banks are of
  2946. different size, the largest is mapped first. For equal size, the first
  2947. bank (CS2#) is mapped first. The first mapping is always for address
  2948. 0x00000000, with any additional banks following immediately to create
  2949. contiguous memory starting from 0.
  2950. Then, the monitor installs itself at the upper end of the SDRAM area
  2951. and allocates memory for use by malloc() and for the global Board
  2952. Info data; also, the exception vector code is copied to the low RAM
  2953. pages, and the final stack is set up.
  2954. Only after this relocation will you have a "normal" C environment;
  2955. until that you are restricted in several ways, mostly because you are
  2956. running from ROM, and because the code will have to be relocated to a
  2957. new address in RAM.
  2958. U-Boot Porting Guide:
  2959. ----------------------
  2960. [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
  2961. list, October 2002]
  2962. int main (int argc, char *argv[])
  2963. {
  2964. sighandler_t no_more_time;
  2965. signal (SIGALRM, no_more_time);
  2966. alarm (PROJECT_DEADLINE - toSec (3 * WEEK));
  2967. if (available_money > available_manpower) {
  2968. pay consultant to port U-Boot;
  2969. return 0;
  2970. }
  2971. Download latest U-Boot source;
  2972. Subscribe to u-boot-users mailing list;
  2973. if (clueless) {
  2974. email ("Hi, I am new to U-Boot, how do I get started?");
  2975. }
  2976. while (learning) {
  2977. Read the README file in the top level directory;
  2978. Read http://www.denx.de/twiki/bin/view/DULG/Manual ;
  2979. Read the source, Luke;
  2980. }
  2981. if (available_money > toLocalCurrency ($2500)) {
  2982. Buy a BDI2000;
  2983. } else {
  2984. Add a lot of aggravation and time;
  2985. }
  2986. Create your own board support subdirectory;
  2987. Create your own board config file;
  2988. while (!running) {
  2989. do {
  2990. Add / modify source code;
  2991. } until (compiles);
  2992. Debug;
  2993. if (clueless)
  2994. email ("Hi, I am having problems...");
  2995. }
  2996. Send patch file to Wolfgang;
  2997. return 0;
  2998. }
  2999. void no_more_time (int sig)
  3000. {
  3001. hire_a_guru();
  3002. }
  3003. Coding Standards:
  3004. -----------------
  3005. All contributions to U-Boot should conform to the Linux kernel
  3006. coding style; see the file "Documentation/CodingStyle" and the script
  3007. "scripts/Lindent" in your Linux kernel source directory. In sources
  3008. originating from U-Boot a style corresponding to "Lindent -pcs" (adding
  3009. spaces before parameters to function calls) is actually used.
  3010. Source files originating from a different project (for example the
  3011. MTD subsystem) are generally exempt from these guidelines and are not
  3012. reformated to ease subsequent migration to newer versions of those
  3013. sources.
  3014. Please note that U-Boot is implemented in C (and to some small parts in
  3015. Assembler); no C++ is used, so please do not use C++ style comments (//)
  3016. in your code.
  3017. Please also stick to the following formatting rules:
  3018. - remove any trailing white space
  3019. - use TAB characters for indentation, not spaces
  3020. - make sure NOT to use DOS '\r\n' line feeds
  3021. - do not add more than 2 empty lines to source files
  3022. - do not add trailing empty lines to source files
  3023. Submissions which do not conform to the standards may be returned
  3024. with a request to reformat the changes.
  3025. Submitting Patches:
  3026. -------------------
  3027. Since the number of patches for U-Boot is growing, we need to
  3028. establish some rules. Submissions which do not conform to these rules
  3029. may be rejected, even when they contain important and valuable stuff.
  3030. Patches shall be sent to the u-boot-users mailing list.
  3031. Please see http://www.denx.de/wiki/U-Boot/Patches for details.
  3032. When you send a patch, please include the following information with
  3033. it:
  3034. * For bug fixes: a description of the bug and how your patch fixes
  3035. this bug. Please try to include a way of demonstrating that the
  3036. patch actually fixes something.
  3037. * For new features: a description of the feature and your
  3038. implementation.
  3039. * A CHANGELOG entry as plaintext (separate from the patch)
  3040. * For major contributions, your entry to the CREDITS file
  3041. * When you add support for a new board, don't forget to add this
  3042. board to the MAKEALL script, too.
  3043. * If your patch adds new configuration options, don't forget to
  3044. document these in the README file.
  3045. * The patch itself. If you are using git (which is *strongly*
  3046. recommended) you can easily generate the patch using the
  3047. "git-format-patch". If you then use "git-send-email" to send it to
  3048. the U-Boot mailing list, you will avoid most of the common problems
  3049. with some other mail clients.
  3050. If you cannot use git, use "diff -purN OLD NEW". If your version of
  3051. diff does not support these options, then get the latest version of
  3052. GNU diff.
  3053. The current directory when running this command shall be the parent
  3054. directory of the U-Boot source tree (i. e. please make sure that
  3055. your patch includes sufficient directory information for the
  3056. affected files).
  3057. We prefer patches as plain text. MIME attachments are discouraged,
  3058. and compressed attachments must not be used.
  3059. * If one logical set of modifications affects or creates several
  3060. files, all these changes shall be submitted in a SINGLE patch file.
  3061. * Changesets that contain different, unrelated modifications shall be
  3062. submitted as SEPARATE patches, one patch per changeset.
  3063. Notes:
  3064. * Before sending the patch, run the MAKEALL script on your patched
  3065. source tree and make sure that no errors or warnings are reported
  3066. for any of the boards.
  3067. * Keep your modifications to the necessary minimum: A patch
  3068. containing several unrelated changes or arbitrary reformats will be
  3069. returned with a request to re-formatting / split it.
  3070. * If you modify existing code, make sure that your new code does not
  3071. add to the memory footprint of the code ;-) Small is beautiful!
  3072. When adding new features, these should compile conditionally only
  3073. (using #ifdef), and the resulting code with the new feature
  3074. disabled must not need more memory than the old code without your
  3075. modification.
  3076. * Remember that there is a size limit of 40 kB per message on the
  3077. u-boot-users mailing list. Bigger patches will be moderated. If
  3078. they are reasonable and not bigger than 100 kB, they will be
  3079. acknowledged. Even bigger patches should be avoided.