README 104 KB

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  1. #
  2. # (C) Copyright 2000 - 2002
  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 and ARM processors, which can be
  27. installed in a boot ROM and used to initialize and test the hardware
  28. or to download and run application code.
  29. The development of U-Boot is closely related to Linux: some parts of
  30. the source code originate in the Linux source tree, we have some
  31. header files in common, and special provision has been made to
  32. support booting of Linux images.
  33. Some attention has been paid to make this software easily
  34. configurable and extendable. For instance, all monitor commands are
  35. implemented with the same call interface, so that it's very easy to
  36. add new commands. Also, instead of permanently adding rarely used
  37. code (for instance hardware test utilities) to the monitor, you can
  38. load and run it dynamically.
  39. Status:
  40. =======
  41. In general, all boards for which a configuration option exists in the
  42. Makefile have been tested to some extent and can be considered
  43. "working". In fact, many of them are used in production systems.
  44. In case of problems see the CHANGELOG and CREDITS files to find out
  45. who contributed the specific port.
  46. Where to get help:
  47. ==================
  48. In case you have questions about, problems with or contributions for
  49. U-Boot you should send a message to the U-Boot mailing list at
  50. <u-boot-users@lists.sourceforge.net>. There is also an archive of
  51. previous traffic on the mailing list - please search the archive
  52. before asking FAQ's. Please see
  53. http://lists.sourceforge.net/lists/listinfo/u-boot-users/
  54. Where we come from:
  55. ===================
  56. - start from 8xxrom sources
  57. - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
  58. - clean up code
  59. - make it easier to add custom boards
  60. - make it possible to add other [PowerPC] CPUs
  61. - extend functions, especially:
  62. * Provide extended interface to Linux boot loader
  63. * S-Record download
  64. * network boot
  65. * PCMCIA / CompactFLash / ATA disk / SCSI ... boot
  66. - create ARMBoot project (http://sourceforge.net/projects/armboot)
  67. - add other CPU families (starting with ARM)
  68. - create U-Boot project (http://sourceforge.net/projects/u-boot)
  69. Names and Spelling:
  70. ===================
  71. The "official" name of this project is "Das U-Boot". The spelling
  72. "U-Boot" shall be used in all written text (documentation, comments
  73. in source files etc.). Example:
  74. This is the README file for the U-Boot project.
  75. File names etc. shall be based on the string "u-boot". Examples:
  76. include/asm-ppc/u-boot.h
  77. #include <asm/u-boot.h>
  78. Variable names, preprocessor constants etc. shall be either based on
  79. the string "u_boot" or on "U_BOOT". Example:
  80. U_BOOT_VERSION u_boot_logo
  81. IH_OS_U_BOOT u_boot_hush_start
  82. Versioning:
  83. ===========
  84. U-Boot uses a 3 level version number containing a version, a
  85. sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2",
  86. sub-version "34", and patchlevel "4".
  87. The patchlevel is used to indicate certain stages of development
  88. between released versions, i. e. officially released versions of
  89. U-Boot will always have a patchlevel of "0".
  90. Directory Hierarchy:
  91. ====================
  92. - board Board dependend files
  93. - common Misc architecture independend functions
  94. - cpu CPU specific files
  95. - disk Code for disk drive partition handling
  96. - doc Documentation (don't expect too much)
  97. - drivers Common used device drivers
  98. - dtt Digital Thermometer and Thermostat drivers
  99. - examples Example code for standalone applications, etc.
  100. - include Header Files
  101. - disk Harddisk interface code
  102. - net Networking code
  103. - ppc Files generic to PowerPC architecture
  104. - post Power On Self Test
  105. - post/arch Symlink to architecture specific Power On Self Test
  106. - post/arch-ppc PowerPC architecture specific Power On Self Test
  107. - post/cpu/mpc8260 MPC8260 CPU specific Power On Self Test
  108. - post/cpu/mpc8xx MPC8xx CPU specific Power On Self Test
  109. - rtc Real Time Clock drivers
  110. - tools Tools to build S-Record or U-Boot images, etc.
  111. - cpu/74xx_7xx Files specific to Motorola MPC74xx and 7xx CPUs
  112. - cpu/arm925t Files specific to ARM 925 CPUs
  113. - cpu/mpc5xx Files specific to Motorola MPC5xx CPUs
  114. - cpu/mpc8xx Files specific to Motorola MPC8xx CPUs
  115. - cpu/mpc824x Files specific to Motorola MPC824x CPUs
  116. - cpu/mpc8260 Files specific to Motorola MPC8260 CPU
  117. - cpu/ppc4xx Files specific to IBM 4xx CPUs
  118. - board/LEOX/ Files specific to boards manufactured by The LEOX team
  119. - board/LEOX/elpt860 Files specific to ELPT860 boards
  120. - board/RPXClassic
  121. Files specific to RPXClassic boards
  122. - board/RPXlite Files specific to RPXlite boards
  123. - board/at91rm9200dk Files specific to AT91RM9200DK boards
  124. - board/c2mon Files specific to c2mon boards
  125. - board/cmi Files specific to cmi boards
  126. - board/cogent Files specific to Cogent boards
  127. (need further configuration)
  128. Files specific to CPCIISER4 boards
  129. - board/cpu86 Files specific to CPU86 boards
  130. - board/cray/ Files specific to boards manufactured by Cray
  131. - board/cray/L1 Files specific to L1 boards
  132. - board/cu824 Files specific to CU824 boards
  133. - board/ebony Files specific to IBM Ebony board
  134. - board/eric Files specific to ERIC boards
  135. - board/esd/ Files specific to boards manufactured by ESD
  136. - board/esd/adciop Files specific to ADCIOP boards
  137. - board/esd/ar405 Files specific to AR405 boards
  138. - board/esd/canbt Files specific to CANBT boards
  139. - board/esd/cpci405 Files specific to CPCI405 boards
  140. - board/esd/cpciiser4 Files specific to CPCIISER4 boards
  141. - board/esd/common Common files for ESD boards
  142. - board/esd/dasa_sim Files specific to DASA_SIM boards
  143. - board/esd/du405 Files specific to DU405 boards
  144. - board/esd/ocrtc Files specific to OCRTC boards
  145. - board/esd/pci405 Files specific to PCI405 boards
  146. - board/esteem192e
  147. Files specific to ESTEEM192E boards
  148. - board/etx094 Files specific to ETX_094 boards
  149. - board/evb64260
  150. Files specific to EVB64260 boards
  151. - board/fads Files specific to FADS boards
  152. - board/flagadm Files specific to FLAGADM boards
  153. - board/gen860t Files specific to GEN860T and GEN860T_SC boards
  154. - board/genietv Files specific to GENIETV boards
  155. - board/gth Files specific to GTH boards
  156. - board/hermes Files specific to HERMES boards
  157. - board/hymod Files specific to HYMOD boards
  158. - board/icu862 Files specific to ICU862 boards
  159. - board/ip860 Files specific to IP860 boards
  160. - board/iphase4539
  161. Files specific to Interphase4539 boards
  162. - board/ivm Files specific to IVMS8/IVML24 boards
  163. - board/lantec Files specific to LANTEC boards
  164. - board/lwmon Files specific to LWMON boards
  165. - board/mbx8xx Files specific to MBX boards
  166. - board/mpc8260ads
  167. Files specific to MPC8260ADS and PQ2FADS-ZU boards
  168. - board/mpl/ Files specific to boards manufactured by MPL
  169. - board/mpl/common Common files for MPL boards
  170. - board/mpl/pip405 Files specific to PIP405 boards
  171. - board/mpl/mip405 Files specific to MIP405 boards
  172. - board/musenki Files specific to MUSEKNI boards
  173. - board/mvs1 Files specific to MVS1 boards
  174. - board/nx823 Files specific to NX823 boards
  175. - board/oxc Files specific to OXC boards
  176. - board/omap1510inn
  177. Files specific to OMAP 1510 Innovator boards
  178. - board/pcippc2 Files specific to PCIPPC2/PCIPPC6 boards
  179. - board/pm826 Files specific to PM826 boards
  180. - board/ppmc8260
  181. Files specific to PPMC8260 boards
  182. - board/rpxsuper
  183. Files specific to RPXsuper boards
  184. - board/rsdproto
  185. Files specific to RSDproto boards
  186. - board/sandpoint
  187. Files specific to Sandpoint boards
  188. - board/sbc8260 Files specific to SBC8260 boards
  189. - board/sacsng Files specific to SACSng boards
  190. - board/siemens Files specific to boards manufactured by Siemens AG
  191. - board/siemens/CCM Files specific to CCM boards
  192. - board/siemens/IAD210 Files specific to IAD210 boards
  193. - board/siemens/SCM Files specific to SCM boards
  194. - board/siemens/pcu_e Files specific to PCU_E boards
  195. - board/sixnet Files specific to SIXNET boards
  196. - board/spd8xx Files specific to SPD8xxTS boards
  197. - board/tqm8260 Files specific to TQM8260 boards
  198. - board/tqm8xx Files specific to TQM8xxL boards
  199. - board/w7o Files specific to W7O boards
  200. - board/walnut405
  201. Files specific to Walnut405 boards
  202. - board/westel/ Files specific to boards manufactured by Westel Wireless
  203. - board/westel/amx860 Files specific to AMX860 boards
  204. - board/utx8245 Files specific to UTX8245 boards
  205. Software Configuration:
  206. =======================
  207. Configuration is usually done using C preprocessor defines; the
  208. rationale behind that is to avoid dead code whenever possible.
  209. There are two classes of configuration variables:
  210. * Configuration _OPTIONS_:
  211. These are selectable by the user and have names beginning with
  212. "CONFIG_".
  213. * Configuration _SETTINGS_:
  214. These depend on the hardware etc. and should not be meddled with if
  215. you don't know what you're doing; they have names beginning with
  216. "CFG_".
  217. Later we will add a configuration tool - probably similar to or even
  218. identical to what's used for the Linux kernel. Right now, we have to
  219. do the configuration by hand, which means creating some symbolic
  220. links and editing some configuration files. We use the TQM8xxL boards
  221. as an example here.
  222. Selection of Processor Architecture and Board Type:
  223. ---------------------------------------------------
  224. For all supported boards there are ready-to-use default
  225. configurations available; just type "make <board_name>_config".
  226. Example: For a TQM823L module type:
  227. cd u-boot
  228. make TQM823L_config
  229. For the Cogent platform, you need to specify the cpu type as well;
  230. e.g. "make cogent_mpc8xx_config". And also configure the cogent
  231. directory according to the instructions in cogent/README.
  232. Configuration Options:
  233. ----------------------
  234. Configuration depends on the combination of board and CPU type; all
  235. such information is kept in a configuration file
  236. "include/configs/<board_name>.h".
  237. Example: For a TQM823L module, all configuration settings are in
  238. "include/configs/TQM823L.h".
  239. Many of the options are named exactly as the corresponding Linux
  240. kernel configuration options. The intention is to make it easier to
  241. build a config tool - later.
  242. The following options need to be configured:
  243. - CPU Type: Define exactly one of
  244. PowerPC based CPUs:
  245. -------------------
  246. CONFIG_MPC823, CONFIG_MPC850, CONFIG_MPC855, CONFIG_MPC860
  247. or CONFIG_MPC5xx
  248. or CONFIG_MPC824X, CONFIG_MPC8260
  249. or CONFIG_IOP480
  250. or CONFIG_405GP
  251. or CONFIG_440
  252. or CONFIG_MPC74xx
  253. or CONFIG_750FX
  254. ARM based CPUs:
  255. ---------------
  256. CONFIG_SA1110
  257. CONFIG_ARM7
  258. CONFIG_PXA250
  259. - Board Type: Define exactly one of
  260. PowerPC based boards:
  261. ---------------------
  262. CONFIG_ADCIOP, CONFIG_ICU862 CONFIG_RPXsuper,
  263. CONFIG_ADS860, CONFIG_IP860, CONFIG_SM850,
  264. CONFIG_AMX860, CONFIG_IPHASE4539, CONFIG_SPD823TS,
  265. CONFIG_AR405, CONFIG_IVML24, CONFIG_SXNI855T,
  266. CONFIG_BAB7xx, CONFIG_IVML24_128, CONFIG_Sandpoint8240,
  267. CONFIG_CANBT, CONFIG_IVML24_256, CONFIG_Sandpoint8245,
  268. CONFIG_CCM, CONFIG_IVMS8, CONFIG_TQM823L,
  269. CONFIG_CPCI405, CONFIG_IVMS8_128, CONFIG_TQM850L,
  270. CONFIG_CPCI4052, CONFIG_IVMS8_256, CONFIG_TQM855L,
  271. CONFIG_CPCIISER4, CONFIG_LANTEC, CONFIG_TQM860L,
  272. CONFIG_CPU86, CONFIG_MBX, CONFIG_TQM8260,
  273. CONFIG_CRAYL1, CONFIG_MBX860T, CONFIG_TTTech,
  274. CONFIG_CU824, CONFIG_MHPC, CONFIG_UTX8245,
  275. CONFIG_DASA_SIM, CONFIG_MIP405, CONFIG_W7OLMC,
  276. CONFIG_DU405, CONFIG_MOUSSE, CONFIG_W7OLMG,
  277. CONFIG_ELPPC, CONFIG_MPC8260ADS, CONFIG_WALNUT405,
  278. CONFIG_ERIC, CONFIG_MUSENKI, CONFIG_ZUMA,
  279. CONFIG_ESTEEM192E, CONFIG_MVS1, CONFIG_c2mon,
  280. CONFIG_ETX094, CONFIG_NX823, CONFIG_cogent_mpc8260,
  281. CONFIG_EVB64260, CONFIG_OCRTC, CONFIG_cogent_mpc8xx,
  282. CONFIG_FADS823, CONFIG_ORSG, CONFIG_ep8260,
  283. CONFIG_FADS850SAR, CONFIG_OXC, CONFIG_gw8260,
  284. CONFIG_FADS860T, CONFIG_PCI405, CONFIG_hermes,
  285. CONFIG_FLAGADM, CONFIG_PCIPPC2, CONFIG_hymod,
  286. CONFIG_FPS850L, CONFIG_PCIPPC6, CONFIG_lwmon,
  287. CONFIG_GEN860T, CONFIG_PIP405, CONFIG_pcu_e,
  288. CONFIG_GENIETV, CONFIG_PM826, CONFIG_ppmc8260,
  289. CONFIG_GTH, CONFIG_RPXClassic, CONFIG_rsdproto,
  290. CONFIG_IAD210, CONFIG_RPXlite, CONFIG_sbc8260,
  291. CONFIG_EBONY, CONFIG_sacsng, CONFIG_FPS860L,
  292. CONFIG_V37, CONFIG_ELPT860, CONFIG_CMI,
  293. CONFIG_NETVIA, CONFIG_RBC823
  294. ARM based boards:
  295. -----------------
  296. CONFIG_HHP_CRADLE, CONFIG_DNP1110, CONFIG_EP7312,
  297. CONFIG_IMPA7, CONFIG_LART, CONFIG_LUBBOCK,
  298. CONFIG_INNOVATOROMAP1510,
  299. CONFIG_SHANNON, CONFIG_SMDK2400, CONFIG_SMDK2410,
  300. CONFIG_TRAB, CONFIG_AT91RM9200DK
  301. - CPU Module Type: (if CONFIG_COGENT is defined)
  302. Define exactly one of
  303. CONFIG_CMA286_60_OLD
  304. --- FIXME --- not tested yet:
  305. CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
  306. CONFIG_CMA287_23, CONFIG_CMA287_50
  307. - Motherboard Type: (if CONFIG_COGENT is defined)
  308. Define exactly one of
  309. CONFIG_CMA101, CONFIG_CMA102
  310. - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
  311. Define one or more of
  312. CONFIG_CMA302
  313. - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
  314. Define one or more of
  315. CONFIG_LCD_HEARTBEAT - update a character position on
  316. the lcd display every second with
  317. a "rotator" |\-/|\-/
  318. - Board flavour: (if CONFIG_MPC8260ADS is defined)
  319. CONFIG_ADSTYPE
  320. Possible values are:
  321. CFG_8260ADS - original MPC8260ADS
  322. CFG_8266ADS - MPC8266ADS (untested)
  323. CFG_PQ2FADS - PQ2FADS-ZU
  324. - MPC824X Family Member (if CONFIG_MPC824X is defined)
  325. Define exactly one of
  326. CONFIG_MPC8240, CONFIG_MPC8245
  327. - 8xx CPU Options: (if using an 8xx cpu)
  328. Define one or more of
  329. CONFIG_8xx_GCLK_FREQ - if get_gclk_freq() can not work e.g.
  330. no 32KHz reference PIT/RTC clock
  331. - Clock Interface:
  332. CONFIG_CLOCKS_IN_MHZ
  333. U-Boot stores all clock information in Hz
  334. internally. For binary compatibility with older Linux
  335. kernels (which expect the clocks passed in the
  336. bd_info data to be in MHz) the environment variable
  337. "clocks_in_mhz" can be defined so that U-Boot
  338. converts clock data to MHZ before passing it to the
  339. Linux kernel.
  340. When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
  341. "clocks_in_mhz=1" is automatically included in the
  342. default environment.
  343. - Console Interface:
  344. Depending on board, define exactly one serial port
  345. (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
  346. CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
  347. console by defining CONFIG_8xx_CONS_NONE
  348. Note: if CONFIG_8xx_CONS_NONE is defined, the serial
  349. port routines must be defined elsewhere
  350. (i.e. serial_init(), serial_getc(), ...)
  351. CONFIG_CFB_CONSOLE
  352. Enables console device for a color framebuffer. Needs following
  353. defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
  354. VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
  355. (default big endian)
  356. VIDEO_HW_RECTFILL graphic chip supports
  357. rectangle fill
  358. (cf. smiLynxEM)
  359. VIDEO_HW_BITBLT graphic chip supports
  360. bit-blit (cf. smiLynxEM)
  361. VIDEO_VISIBLE_COLS visible pixel columns
  362. (cols=pitch)
  363. VIDEO_VISIBLE_ROWS visible pixel rows
  364. VIDEO_PIXEL_SIZE bytes per pixel
  365. VIDEO_DATA_FORMAT graphic data format
  366. (0-5, cf. cfb_console.c)
  367. VIDEO_FB_ADRS framebuffer address
  368. VIDEO_KBD_INIT_FCT keyboard int fct
  369. (i.e. i8042_kbd_init())
  370. VIDEO_TSTC_FCT test char fct
  371. (i.e. i8042_tstc)
  372. VIDEO_GETC_FCT get char fct
  373. (i.e. i8042_getc)
  374. CONFIG_CONSOLE_CURSOR cursor drawing on/off
  375. (requires blink timer
  376. cf. i8042.c)
  377. CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
  378. CONFIG_CONSOLE_TIME display time/date info in
  379. upper right corner
  380. (requires CFG_CMD_DATE)
  381. CONFIG_VIDEO_LOGO display Linux logo in
  382. upper left corner
  383. CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
  384. linux_logo.h for logo.
  385. Requires CONFIG_VIDEO_LOGO
  386. CONFIG_CONSOLE_EXTRA_INFO
  387. addional board info beside
  388. the logo
  389. When CONFIG_CFB_CONSOLE is defined, video console is
  390. default i/o. Serial console can be forced with
  391. environment 'console=serial'.
  392. - Console Baudrate:
  393. CONFIG_BAUDRATE - in bps
  394. Select one of the baudrates listed in
  395. CFG_BAUDRATE_TABLE, see below.
  396. - Interrupt driven serial port input:
  397. CONFIG_SERIAL_SOFTWARE_FIFO
  398. PPC405GP only.
  399. Use an interrupt handler for receiving data on the
  400. serial port. It also enables using hardware handshake
  401. (RTS/CTS) and UART's built-in FIFO. Set the number of
  402. bytes the interrupt driven input buffer should have.
  403. Set to 0 to disable this feature (this is the default).
  404. This will also disable hardware handshake.
  405. - Console UART Number:
  406. CONFIG_UART1_CONSOLE
  407. IBM PPC4xx only.
  408. If defined internal UART1 (and not UART0) is used
  409. as default U-Boot console.
  410. - Boot Delay: CONFIG_BOOTDELAY - in seconds
  411. Delay before automatically booting the default image;
  412. set to -1 to disable autoboot.
  413. See doc/README.autoboot for these options that
  414. work with CONFIG_BOOTDELAY. None are required.
  415. CONFIG_BOOT_RETRY_TIME
  416. CONFIG_BOOT_RETRY_MIN
  417. CONFIG_AUTOBOOT_KEYED
  418. CONFIG_AUTOBOOT_PROMPT
  419. CONFIG_AUTOBOOT_DELAY_STR
  420. CONFIG_AUTOBOOT_STOP_STR
  421. CONFIG_AUTOBOOT_DELAY_STR2
  422. CONFIG_AUTOBOOT_STOP_STR2
  423. CONFIG_ZERO_BOOTDELAY_CHECK
  424. CONFIG_RESET_TO_RETRY
  425. - Autoboot Command:
  426. CONFIG_BOOTCOMMAND
  427. Only needed when CONFIG_BOOTDELAY is enabled;
  428. define a command string that is automatically executed
  429. when no character is read on the console interface
  430. within "Boot Delay" after reset.
  431. CONFIG_BOOTARGS
  432. This can be used to pass arguments to the bootm
  433. command. The value of CONFIG_BOOTARGS goes into the
  434. environment value "bootargs".
  435. CONFIG_RAMBOOT and CONFIG_NFSBOOT
  436. The value of these goes into the environment as
  437. "ramboot" and "nfsboot" respectively, and can be used
  438. as a convenience, when switching between booting from
  439. ram and nfs.
  440. - Pre-Boot Commands:
  441. CONFIG_PREBOOT
  442. When this option is #defined, the existence of the
  443. environment variable "preboot" will be checked
  444. immediately before starting the CONFIG_BOOTDELAY
  445. countdown and/or running the auto-boot command resp.
  446. entering interactive mode.
  447. This feature is especially useful when "preboot" is
  448. automatically generated or modified. For an example
  449. see the LWMON board specific code: here "preboot" is
  450. modified when the user holds down a certain
  451. combination of keys on the (special) keyboard when
  452. booting the systems
  453. - Serial Download Echo Mode:
  454. CONFIG_LOADS_ECHO
  455. If defined to 1, all characters received during a
  456. serial download (using the "loads" command) are
  457. echoed back. This might be needed by some terminal
  458. emulations (like "cu"), but may as well just take
  459. time on others. This setting #define's the initial
  460. value of the "loads_echo" environment variable.
  461. - Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined)
  462. CONFIG_KGDB_BAUDRATE
  463. Select one of the baudrates listed in
  464. CFG_BAUDRATE_TABLE, see below.
  465. - Monitor Functions:
  466. CONFIG_COMMANDS
  467. Most monitor functions can be selected (or
  468. de-selected) by adjusting the definition of
  469. CONFIG_COMMANDS; to select individual functions,
  470. #define CONFIG_COMMANDS by "OR"ing any of the
  471. following values:
  472. #define enables commands:
  473. -------------------------
  474. CFG_CMD_ASKENV * ask for env variable
  475. CFG_CMD_BDI bdinfo
  476. CFG_CMD_BEDBUG Include BedBug Debugger
  477. CFG_CMD_BOOTD bootd
  478. CFG_CMD_CACHE icache, dcache
  479. CFG_CMD_CONSOLE coninfo
  480. CFG_CMD_DATE * support for RTC, date/time...
  481. CFG_CMD_DHCP DHCP support
  482. CFG_CMD_ECHO * echo arguments
  483. CFG_CMD_EEPROM * EEPROM read/write support
  484. CFG_CMD_ELF bootelf, bootvx
  485. CFG_CMD_ENV saveenv
  486. CFG_CMD_FDC * Floppy Disk Support
  487. CFG_CMD_FAT FAT partition support
  488. CFG_CMD_FDOS * Dos diskette Support
  489. CFG_CMD_FLASH flinfo, erase, protect
  490. CFG_CMD_FPGA FPGA device initialization support
  491. CFG_CMD_I2C * I2C serial bus support
  492. CFG_CMD_IDE * IDE harddisk support
  493. CFG_CMD_IMI iminfo
  494. CFG_CMD_IMMAP * IMMR dump support
  495. CFG_CMD_IRQ * irqinfo
  496. CFG_CMD_KGDB * kgdb
  497. CFG_CMD_LOADB loadb
  498. CFG_CMD_LOADS loads
  499. CFG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
  500. loop, mtest
  501. CFG_CMD_MMC MMC memory mapped support
  502. CFG_CMD_MII MII utility commands
  503. CFG_CMD_NET bootp, tftpboot, rarpboot
  504. CFG_CMD_PCI * pciinfo
  505. CFG_CMD_PCMCIA * PCMCIA support
  506. CFG_CMD_REGINFO * Register dump
  507. CFG_CMD_RUN run command in env variable
  508. CFG_CMD_SCSI * SCSI Support
  509. CFG_CMD_SETGETDCR Support for DCR Register access (4xx only)
  510. CFG_CMD_SPI * SPI serial bus support
  511. CFG_CMD_USB * USB support
  512. CFG_CMD_BSP * Board SPecific functions
  513. -----------------------------------------------
  514. CFG_CMD_ALL all
  515. CFG_CMD_DFL Default configuration; at the moment
  516. this is includes all commands, except
  517. the ones marked with "*" in the list
  518. above.
  519. If you don't define CONFIG_COMMANDS it defaults to
  520. CFG_CMD_DFL in include/cmd_confdefs.h. A board can
  521. override the default settings in the respective
  522. include file.
  523. EXAMPLE: If you want all functions except of network
  524. support you can write:
  525. #define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET)
  526. Note: Don't enable the "icache" and "dcache" commands
  527. (configuration option CFG_CMD_CACHE) unless you know
  528. what you (and your U-Boot users) are doing. Data
  529. cache cannot be enabled on systems like the 8xx or
  530. 8260 (where accesses to the IMMR region must be
  531. uncached), and it cannot be disabled on all other
  532. systems where we (mis-) use the data cache to hold an
  533. initial stack and some data.
  534. XXX - this list needs to get updated!
  535. - Watchdog:
  536. CONFIG_WATCHDOG
  537. If this variable is defined, it enables watchdog
  538. support. There must support in the platform specific
  539. code for a watchdog. For the 8xx and 8260 CPUs, the
  540. SIU Watchdog feature is enabled in the SYPCR
  541. register.
  542. - U-Boot Version:
  543. CONFIG_VERSION_VARIABLE
  544. If this variable is defined, an environment variable
  545. named "ver" is created by U-Boot showing the U-Boot
  546. version as printed by the "version" command.
  547. This variable is readonly.
  548. - Real-Time Clock:
  549. When CFG_CMD_DATE is selected, the type of the RTC
  550. has to be selected, too. Define exactly one of the
  551. following options:
  552. CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
  553. CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
  554. CONFIG_RTC_MC146818 - use MC146818 RTC
  555. CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
  556. CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
  557. CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
  558. CONFIG_RTC_DS164x - use Dallas DS164x RTC
  559. Note that if the RTC uses I2C, then the I2C interface
  560. must also be configured. See I2C Support, below.
  561. - Timestamp Support:
  562. When CONFIG_TIMESTAMP is selected, the timestamp
  563. (date and time) of an image is printed by image
  564. commands like bootm or iminfo. This option is
  565. automatically enabled when you select CFG_CMD_DATE .
  566. - Partition Support:
  567. CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
  568. and/or CONFIG_ISO_PARTITION
  569. If IDE or SCSI support is enabled (CFG_CMD_IDE or
  570. CFG_CMD_SCSI) you must configure support for at least
  571. one partition type as well.
  572. - IDE Reset method:
  573. CONFIG_IDE_RESET_ROUTINE
  574. Set this to define that instead of a reset Pin, the
  575. routine ide_set_reset(int idereset) will be used.
  576. - ATAPI Support:
  577. CONFIG_ATAPI
  578. Set this to enable ATAPI support.
  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_EEPRO100
  593. Support for Intel 82557/82559/82559ER chips.
  594. Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom
  595. write routine for first time initialisation.
  596. CONFIG_TULIP
  597. Support for Digital 2114x chips.
  598. Optional CONFIG_TULIP_SELECT_MEDIA for board specific
  599. modem chip initialisation (KS8761/QS6611).
  600. CONFIG_NATSEMI
  601. Support for National dp83815 chips.
  602. CONFIG_NS8382X
  603. Support for National dp8382[01] gigabit chips.
  604. - NETWORK Support (other):
  605. CONFIG_DRIVER_LAN91C96
  606. Support for SMSC's LAN91C96 chips.
  607. CONFIG_LAN91C96_BASE
  608. Define this to hold the physical address
  609. of the LAN91C96's I/O space
  610. CONFIG_LAN91C96_USE_32_BIT
  611. Define this to enable 32 bit addressing
  612. - USB Support:
  613. At the moment only the UHCI host controller is
  614. supported (PIP405, MIP405); define
  615. CONFIG_USB_UHCI to enable it.
  616. define CONFIG_USB_KEYBOARD to enable the USB Keyboard
  617. end define CONFIG_USB_STORAGE to enable the USB
  618. storage devices.
  619. Note:
  620. Supported are USB Keyboards and USB Floppy drives
  621. (TEAC FD-05PUB).
  622. - MMC Support:
  623. The MMC controller on the Intel PXA is supported. To
  624. enable this define CONFIG_MMC. The MMC can be
  625. accessed from the boot prompt by mapping the device
  626. to physical memory similar to flash. Command line is
  627. enabled with CFG_CMD_MMC. The MMC driver also works with
  628. the FAT fs. This is enabled with CFG_CMD_FAT.
  629. - Keyboard Support:
  630. CONFIG_ISA_KEYBOARD
  631. Define this to enable standard (PC-Style) keyboard
  632. support
  633. CONFIG_I8042_KBD
  634. Standard PC keyboard driver with US (is default) and
  635. GERMAN key layout (switch via environment 'keymap=de') support.
  636. Export function i8042_kbd_init, i8042_tstc and i8042_getc
  637. for cfb_console. Supports cursor blinking.
  638. - Video support:
  639. CONFIG_VIDEO
  640. Define this to enable video support (for output to
  641. video).
  642. CONFIG_VIDEO_CT69000
  643. Enable Chips & Technologies 69000 Video chip
  644. CONFIG_VIDEO_SMI_LYNXEM
  645. Enable Silicon Motion SMI 712/710/810 Video chip
  646. Videomode are selected via environment 'videomode' with
  647. standard LiLo mode numbers.
  648. Following modes are supported (* is default):
  649. 800x600 1024x768 1280x1024
  650. 256 (8bit) 303* 305 307
  651. 65536 (16bit) 314 317 31a
  652. 16,7 Mill (24bit) 315 318 31b
  653. (i.e. setenv videomode 317; saveenv; reset;)
  654. CONFIG_VIDEO_SED13806
  655. Enable Epson SED13806 driver. This driver supports 8bpp
  656. and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
  657. or CONFIG_VIDEO_SED13806_16BPP
  658. - Keyboard Support:
  659. CONFIG_KEYBOARD
  660. Define this to enable a custom keyboard support.
  661. This simply calls drv_keyboard_init() which must be
  662. defined in your board-specific files.
  663. The only board using this so far is RBC823.
  664. - LCD Support: CONFIG_LCD
  665. Define this to enable LCD support (for output to LCD
  666. display); also select one of the supported displays
  667. by defining one of these:
  668. CONFIG_NEC_NL6648AC33:
  669. NEC NL6648AC33-18. Active, color, single scan.
  670. CONFIG_NEC_NL6648BC20
  671. NEC NL6648BC20-08. 6.5", 640x480.
  672. Active, color, single scan.
  673. CONFIG_SHARP_16x9
  674. Sharp 320x240. Active, color, single scan.
  675. It isn't 16x9, and I am not sure what it is.
  676. CONFIG_SHARP_LQ64D341
  677. Sharp LQ64D341 display, 640x480.
  678. Active, color, single scan.
  679. CONFIG_HLD1045
  680. HLD1045 display, 640x480.
  681. Active, color, single scan.
  682. CONFIG_OPTREX_BW
  683. Optrex CBL50840-2 NF-FW 99 22 M5
  684. or
  685. Hitachi LMG6912RPFC-00T
  686. or
  687. Hitachi SP14Q002
  688. 320x240. Black & white.
  689. Normally display is black on white background; define
  690. CFG_WHITE_ON_BLACK to get it inverted.
  691. - Spash Screen Support: CONFIG_SPLASH_SCREEN
  692. If this option is set, the environment is checked for
  693. a variable "splashimage". If found, the usual display
  694. of logo, copyright and system information on the LCD
  695. is supressed and the BMP image at the address
  696. specified in "splashimage" is loaded instead. The
  697. console is redirected to the "nulldev", too. This
  698. allows for a "silent" boot where a splash screen is
  699. loaded very quickly after power-on.
  700. - Ethernet address:
  701. CONFIG_ETHADDR
  702. CONFIG_ETH2ADDR
  703. CONFIG_ETH3ADDR
  704. Define a default value for ethernet address to use
  705. for the respective ethernet interface, in case this
  706. is not determined automatically.
  707. - IP address:
  708. CONFIG_IPADDR
  709. Define a default value for the IP address to use for
  710. the default ethernet interface, in case this is not
  711. determined through e.g. bootp.
  712. - Server IP address:
  713. CONFIG_SERVERIP
  714. Defines a default value for theIP address of a TFTP
  715. server to contact when using the "tftboot" command.
  716. - BOOTP Recovery Mode:
  717. CONFIG_BOOTP_RANDOM_DELAY
  718. If you have many targets in a network that try to
  719. boot using BOOTP, you may want to avoid that all
  720. systems send out BOOTP requests at precisely the same
  721. moment (which would happen for instance at recovery
  722. from a power failure, when all systems will try to
  723. boot, thus flooding the BOOTP server. Defining
  724. CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
  725. inserted before sending out BOOTP requests. The
  726. following delays are insterted then:
  727. 1st BOOTP request: delay 0 ... 1 sec
  728. 2nd BOOTP request: delay 0 ... 2 sec
  729. 3rd BOOTP request: delay 0 ... 4 sec
  730. 4th and following
  731. BOOTP requests: delay 0 ... 8 sec
  732. - DHCP Advanced Options:
  733. CONFIG_BOOTP_MASK
  734. You can fine tune the DHCP functionality by adding
  735. these flags to the CONFIG_BOOTP_MASK define:
  736. CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
  737. serverip from a DHCP server, it is possible that more
  738. than one DNS serverip is offered to the client.
  739. If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
  740. serverip will be stored in the additional environment
  741. variable "dnsip2". The first DNS serverip is always
  742. stored in the variable "dnsip", when CONFIG_BOOTP_DNS
  743. is added to the CONFIG_BOOTP_MASK.
  744. CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
  745. to do a dynamic update of a DNS server. To do this, they
  746. need the hostname of the DHCP requester.
  747. If CONFIG_BOOP_SEND_HOSTNAME is added to the
  748. CONFIG_BOOTP_MASK, the content of the "hostname"
  749. environment variable is passed as option 12 to
  750. the DHCP server.
  751. - Status LED: CONFIG_STATUS_LED
  752. Several configurations allow to display the current
  753. status using a LED. For instance, the LED will blink
  754. fast while running U-Boot code, stop blinking as
  755. soon as a reply to a BOOTP request was received, and
  756. start blinking slow once the Linux kernel is running
  757. (supported by a status LED driver in the Linux
  758. kernel). Defining CONFIG_STATUS_LED enables this
  759. feature in U-Boot.
  760. - CAN Support: CONFIG_CAN_DRIVER
  761. Defining CONFIG_CAN_DRIVER enables CAN driver support
  762. on those systems that support this (optional)
  763. feature, like the TQM8xxL modules.
  764. - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
  765. These enable I2C serial bus commands. Defining either of
  766. (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
  767. include the appropriate I2C driver for the selected cpu.
  768. This will allow you to use i2c commands at the u-boot
  769. command line (as long as you set CFG_CMD_I2C in
  770. CONFIG_COMMANDS) and communicate with i2c based realtime
  771. clock chips. See common/cmd_i2c.c for a description of the
  772. command line interface.
  773. CONFIG_HARD_I2C selects the CPM hardware driver for I2C.
  774. CONFIG_SOFT_I2C configures u-boot to use a software (aka
  775. bit-banging) driver instead of CPM or similar hardware
  776. support for I2C.
  777. There are several other quantities that must also be
  778. defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
  779. In both cases you will need to define CFG_I2C_SPEED
  780. to be the frequency (in Hz) at which you wish your i2c bus
  781. to run and CFG_I2C_SLAVE to be the address of this node (ie
  782. the cpu's i2c node address).
  783. Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c)
  784. sets the cpu up as a master node and so its address should
  785. therefore be cleared to 0 (See, eg, MPC823e User's Manual
  786. p.16-473). So, set CFG_I2C_SLAVE to 0.
  787. That's all that's required for CONFIG_HARD_I2C.
  788. If you use the software i2c interface (CONFIG_SOFT_I2C)
  789. then the following macros need to be defined (examples are
  790. from include/configs/lwmon.h):
  791. I2C_INIT
  792. (Optional). Any commands necessary to enable the I2C
  793. controller or configure ports.
  794. eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
  795. I2C_PORT
  796. (Only for MPC8260 CPU). The I/O port to use (the code
  797. assumes both bits are on the same port). Valid values
  798. are 0..3 for ports A..D.
  799. I2C_ACTIVE
  800. The code necessary to make the I2C data line active
  801. (driven). If the data line is open collector, this
  802. define can be null.
  803. eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
  804. I2C_TRISTATE
  805. The code necessary to make the I2C data line tri-stated
  806. (inactive). If the data line is open collector, this
  807. define can be null.
  808. eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
  809. I2C_READ
  810. Code that returns TRUE if the I2C data line is high,
  811. FALSE if it is low.
  812. eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
  813. I2C_SDA(bit)
  814. If <bit> is TRUE, sets the I2C data line high. If it
  815. is FALSE, it clears it (low).
  816. eg: #define I2C_SDA(bit) \
  817. if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
  818. else immr->im_cpm.cp_pbdat &= ~PB_SDA
  819. I2C_SCL(bit)
  820. If <bit> is TRUE, sets the I2C clock line high. If it
  821. is FALSE, it clears it (low).
  822. eg: #define I2C_SCL(bit) \
  823. if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
  824. else immr->im_cpm.cp_pbdat &= ~PB_SCL
  825. I2C_DELAY
  826. This delay is invoked four times per clock cycle so this
  827. controls the rate of data transfer. The data rate thus
  828. is 1 / (I2C_DELAY * 4). Often defined to be something
  829. like:
  830. #define I2C_DELAY udelay(2)
  831. CFG_I2C_INIT_BOARD
  832. When a board is reset during an i2c bus transfer
  833. chips might think that the current transfer is still
  834. in progress. On some boards it is possible to access
  835. the i2c SCLK line directly, either by using the
  836. processor pin as a GPIO or by having a second pin
  837. connected to the bus. If this option is defined a
  838. custom i2c_init_board() routine in boards/xxx/board.c
  839. is run early in the boot sequence.
  840. - SPI Support: CONFIG_SPI
  841. Enables SPI driver (so far only tested with
  842. SPI EEPROM, also an instance works with Crystal A/D and
  843. D/As on the SACSng board)
  844. CONFIG_SPI_X
  845. Enables extended (16-bit) SPI EEPROM addressing.
  846. (symmetrical to CONFIG_I2C_X)
  847. CONFIG_SOFT_SPI
  848. Enables a software (bit-bang) SPI driver rather than
  849. using hardware support. This is a general purpose
  850. driver that only requires three general I/O port pins
  851. (two outputs, one input) to function. If this is
  852. defined, the board configuration must define several
  853. SPI configuration items (port pins to use, etc). For
  854. an example, see include/configs/sacsng.h.
  855. - FPGA Support: CONFIG_FPGA_COUNT
  856. Specify the number of FPGA devices to support.
  857. CONFIG_FPGA
  858. Used to specify the types of FPGA devices. For
  859. example,
  860. #define CONFIG_FPGA CFG_XILINX_VIRTEX2
  861. CFG_FPGA_PROG_FEEDBACK
  862. Enable printing of hash marks during FPGA
  863. configuration.
  864. CFG_FPGA_CHECK_BUSY
  865. Enable checks on FPGA configuration interface busy
  866. status by the configuration function. This option
  867. will require a board or device specific function to
  868. be written.
  869. CONFIG_FPGA_DELAY
  870. If defined, a function that provides delays in the
  871. FPGA configuration driver.
  872. CFG_FPGA_CHECK_CTRLC
  873. Allow Control-C to interrupt FPGA configuration
  874. CFG_FPGA_CHECK_ERROR
  875. Check for configuration errors during FPGA bitfile
  876. loading. For example, abort during Virtex II
  877. configuration if the INIT_B line goes low (which
  878. indicated a CRC error).
  879. CFG_FPGA_WAIT_INIT
  880. Maximum time to wait for the INIT_B line to deassert
  881. after PROB_B has been deasserted during a Virtex II
  882. FPGA configuration sequence. The default time is 500 mS.
  883. CFG_FPGA_WAIT_BUSY
  884. Maximum time to wait for BUSY to deassert during
  885. Virtex II FPGA configuration. The default is 5 mS.
  886. CFG_FPGA_WAIT_CONFIG
  887. Time to wait after FPGA configuration. The default is
  888. 200 mS.
  889. - FPGA Support: CONFIG_FPGA_COUNT
  890. Specify the number of FPGA devices to support.
  891. CONFIG_FPGA
  892. Used to specify the types of FPGA devices. For example,
  893. #define CONFIG_FPGA CFG_XILINX_VIRTEX2
  894. CFG_FPGA_PROG_FEEDBACK
  895. Enable printing of hash marks during FPGA configuration.
  896. CFG_FPGA_CHECK_BUSY
  897. Enable checks on FPGA configuration interface busy
  898. status by the configuration function. This option
  899. will require a board or device specific function to
  900. be written.
  901. CONFIG_FPGA_DELAY
  902. If defined, a function that provides delays in the FPGA
  903. configuration driver.
  904. CFG_FPGA_CHECK_CTRLC
  905. Allow Control-C to interrupt FPGA configuration
  906. CFG_FPGA_CHECK_ERROR
  907. Check for configuration errors during FPGA bitfile
  908. loading. For example, abort during Virtex II
  909. configuration if the INIT_B line goes low (which
  910. indicated a CRC error).
  911. CFG_FPGA_WAIT_INIT
  912. Maximum time to wait for the INIT_B line to deassert
  913. after PROB_B has been deasserted during a Virtex II
  914. FPGA configuration sequence. The default time is 500
  915. mS.
  916. CFG_FPGA_WAIT_BUSY
  917. Maximum time to wait for BUSY to deassert during
  918. Virtex II FPGA configuration. The default is 5 mS.
  919. CFG_FPGA_WAIT_CONFIG
  920. Time to wait after FPGA configuration. The default is
  921. 200 mS.
  922. - Configuration Management:
  923. CONFIG_IDENT_STRING
  924. If defined, this string will be added to the U-Boot
  925. version information (U_BOOT_VERSION)
  926. - Vendor Parameter Protection:
  927. U-Boot considers the values of the environment
  928. variables "serial#" (Board Serial Number) and
  929. "ethaddr" (Ethernet Address) to bb parameters that
  930. are set once by the board vendor / manufacturer, and
  931. protects these variables from casual modification by
  932. the user. Once set, these variables are read-only,
  933. and write or delete attempts are rejected. You can
  934. change this behviour:
  935. If CONFIG_ENV_OVERWRITE is #defined in your config
  936. file, the write protection for vendor parameters is
  937. completely disabled. Anybody can change or delete
  938. these parameters.
  939. Alternatively, if you #define _both_ CONFIG_ETHADDR
  940. _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
  941. ethernet address is installed in the environment,
  942. which can be changed exactly ONCE by the user. [The
  943. serial# is unaffected by this, i. e. it remains
  944. read-only.]
  945. - Protected RAM:
  946. CONFIG_PRAM
  947. Define this variable to enable the reservation of
  948. "protected RAM", i. e. RAM which is not overwritten
  949. by U-Boot. Define CONFIG_PRAM to hold the number of
  950. kB you want to reserve for pRAM. You can overwrite
  951. this default value by defining an environment
  952. variable "pram" to the number of kB you want to
  953. reserve. Note that the board info structure will
  954. still show the full amount of RAM. If pRAM is
  955. reserved, a new environment variable "mem" will
  956. automatically be defined to hold the amount of
  957. remaining RAM in a form that can be passed as boot
  958. argument to Linux, for instance like that:
  959. setenv bootargs ... mem=\$(mem)
  960. saveenv
  961. This way you can tell Linux not to use this memory,
  962. either, which results in a memory region that will
  963. not be affected by reboots.
  964. *WARNING* If your board configuration uses automatic
  965. detection of the RAM size, you must make sure that
  966. this memory test is non-destructive. So far, the
  967. following board configurations are known to be
  968. "pRAM-clean":
  969. ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
  970. HERMES, IP860, RPXlite, LWMON, LANTEC,
  971. PCU_E, FLAGADM, TQM8260
  972. - Error Recovery:
  973. CONFIG_PANIC_HANG
  974. Define this variable to stop the system in case of a
  975. fatal error, so that you have to reset it manually.
  976. This is probably NOT a good idea for an embedded
  977. system where you want to system to reboot
  978. automatically as fast as possible, but it may be
  979. useful during development since you can try to debug
  980. the conditions that lead to the situation.
  981. CONFIG_NET_RETRY_COUNT
  982. This variable defines the number of retries for
  983. network operations like ARP, RARP, TFTP, or BOOTP
  984. before giving up the operation. If not defined, a
  985. default value of 5 is used.
  986. - Command Interpreter:
  987. CFG_HUSH_PARSER
  988. Define this variable to enable the "hush" shell (from
  989. Busybox) as command line interpreter, thus enabling
  990. powerful command line syntax like
  991. if...then...else...fi conditionals or `&&' and '||'
  992. constructs ("shell scripts").
  993. If undefined, you get the old, much simpler behaviour
  994. with a somewhat smaller memory footprint.
  995. CFG_PROMPT_HUSH_PS2
  996. This defines the secondary prompt string, which is
  997. printed when the command interpreter needs more input
  998. to complete a command. Usually "> ".
  999. Note:
  1000. In the current implementation, the local variables
  1001. space and global environment variables space are
  1002. separated. Local variables are those you define by
  1003. simply typing `name=value'. To access a local
  1004. variable later on, you have write `$name' or
  1005. `${name}'; to execute the contents of a variable
  1006. directly type `$name' at the command prompt.
  1007. Global environment variables are those you use
  1008. setenv/printenv to work with. To run a command stored
  1009. in such a variable, you need to use the run command,
  1010. and you must not use the '$' sign to access them.
  1011. To store commands and special characters in a
  1012. variable, please use double quotation marks
  1013. surrounding the whole text of the variable, instead
  1014. of the backslashes before semicolons and special
  1015. symbols.
  1016. - Default Environment
  1017. CONFIG_EXTRA_ENV_SETTINGS
  1018. Define this to contain any number of null terminated
  1019. strings (variable = value pairs) that will be part of
  1020. the default enviroment compiled into the boot image.
  1021. For example, place something like this in your
  1022. board's config file:
  1023. #define CONFIG_EXTRA_ENV_SETTINGS \
  1024. "myvar1=value1\0" \
  1025. "myvar2=value2\0"
  1026. Warning: This method is based on knowledge about the
  1027. internal format how the environment is stored by the
  1028. U-Boot code. This is NOT an official, exported
  1029. interface! Although it is unlikely that this format
  1030. will change soon, but there is no guarantee either.
  1031. You better know what you are doing here.
  1032. Note: overly (ab)use of the default environment is
  1033. discouraged. Make sure to check other ways to preset
  1034. the environment like the autoscript function or the
  1035. boot command first.
  1036. - DataFlash Support
  1037. CONFIG_HAS_DATAFLASH
  1038. Defining this option enables DataFlash features and
  1039. allows to read/write in Dataflash via the standard
  1040. commands cp, md...
  1041. - Show boot progress
  1042. CONFIG_SHOW_BOOT_PROGRESS
  1043. Defining this option allows to add some board-
  1044. specific code (calling a user-provided function
  1045. "show_boot_progress(int)") that enables you to show
  1046. the system's boot progress on some display (for
  1047. example, some LED's) on your board. At the moment,
  1048. the following checkpoints are implemented:
  1049. Arg Where When
  1050. 1 common/cmd_bootm.c before attempting to boot an image
  1051. -1 common/cmd_bootm.c Image header has bad magic number
  1052. 2 common/cmd_bootm.c Image header has correct magic number
  1053. -2 common/cmd_bootm.c Image header has bad checksum
  1054. 3 common/cmd_bootm.c Image header has correct checksum
  1055. -3 common/cmd_bootm.c Image data has bad checksum
  1056. 4 common/cmd_bootm.c Image data has correct checksum
  1057. -4 common/cmd_bootm.c Image is for unsupported architecture
  1058. 5 common/cmd_bootm.c Architecture check OK
  1059. -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
  1060. 6 common/cmd_bootm.c Image Type check OK
  1061. -6 common/cmd_bootm.c gunzip uncompression error
  1062. -7 common/cmd_bootm.c Unimplemented compression type
  1063. 7 common/cmd_bootm.c Uncompression OK
  1064. -8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
  1065. 8 common/cmd_bootm.c Image Type check OK
  1066. -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
  1067. 9 common/cmd_bootm.c Start initial ramdisk verification
  1068. -10 common/cmd_bootm.c Ramdisk header has bad magic number
  1069. -11 common/cmd_bootm.c Ramdisk header has bad checksum
  1070. 10 common/cmd_bootm.c Ramdisk header is OK
  1071. -12 common/cmd_bootm.c Ramdisk data has bad checksum
  1072. 11 common/cmd_bootm.c Ramdisk data has correct checksum
  1073. 12 common/cmd_bootm.c Ramdisk verification complete, start loading
  1074. -13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk)
  1075. 13 common/cmd_bootm.c Start multifile image verification
  1076. 14 common/cmd_bootm.c No initial ramdisk, no multifile, continue.
  1077. 15 common/cmd_bootm.c All preparation done, transferring control to OS
  1078. -1 common/cmd_doc.c Bad usage of "doc" command
  1079. -1 common/cmd_doc.c No boot device
  1080. -1 common/cmd_doc.c Unknown Chip ID on boot device
  1081. -1 common/cmd_doc.c Read Error on boot device
  1082. -1 common/cmd_doc.c Image header has bad magic number
  1083. -1 common/cmd_ide.c Bad usage of "ide" command
  1084. -1 common/cmd_ide.c No boot device
  1085. -1 common/cmd_ide.c Unknown boot device
  1086. -1 common/cmd_ide.c Unknown partition table
  1087. -1 common/cmd_ide.c Invalid partition type
  1088. -1 common/cmd_ide.c Read Error on boot device
  1089. -1 common/cmd_ide.c Image header has bad magic number
  1090. -1 common/cmd_nvedit.c Environment not changable, but has bad CRC
  1091. Modem Support:
  1092. --------------
  1093. [so far only for SMDK2400 and TRAB boards]
  1094. - Modem support endable:
  1095. CONFIG_MODEM_SUPPORT
  1096. - RTS/CTS Flow control enable:
  1097. CONFIG_HWFLOW
  1098. - Modem debug support:
  1099. CONFIG_MODEM_SUPPORT_DEBUG
  1100. Enables debugging stuff (char screen[1024], dbg())
  1101. for modem support. Useful only with BDI2000.
  1102. - General:
  1103. In the target system modem support is enabled when a
  1104. specific key (key combination) is pressed during
  1105. power-on. Otherwise U-Boot will boot normally
  1106. (autoboot). The key_pressed() fuction is called from
  1107. board_init(). Currently key_pressed() is a dummy
  1108. function, returning 1 and thus enabling modem
  1109. initialization.
  1110. If there are no modem init strings in the
  1111. environment, U-Boot proceed to autoboot; the
  1112. previous output (banner, info printfs) will be
  1113. supressed, though.
  1114. See also: doc/README.Modem
  1115. Configuration Settings:
  1116. -----------------------
  1117. - CFG_LONGHELP: Defined when you want long help messages included;
  1118. undefine this when you're short of memory.
  1119. - CFG_PROMPT: This is what U-Boot prints on the console to
  1120. prompt for user input.
  1121. - CFG_CBSIZE: Buffer size for input from the Console
  1122. - CFG_PBSIZE: Buffer size for Console output
  1123. - CFG_MAXARGS: max. Number of arguments accepted for monitor commands
  1124. - CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to
  1125. the application (usually a Linux kernel) when it is
  1126. booted
  1127. - CFG_BAUDRATE_TABLE:
  1128. List of legal baudrate settings for this board.
  1129. - CFG_CONSOLE_INFO_QUIET
  1130. Suppress display of console information at boot.
  1131. - CFG_CONSOLE_IS_IN_ENV
  1132. If the board specific function
  1133. extern int overwrite_console (void);
  1134. returns 1, the stdin, stderr and stdout are switched to the
  1135. serial port, else the settings in the environment are used.
  1136. - CFG_CONSOLE_OVERWRITE_ROUTINE
  1137. Enable the call to overwrite_console().
  1138. - CFG_CONSOLE_ENV_OVERWRITE
  1139. Enable overwrite of previous console environment settings.
  1140. - CFG_MEMTEST_START, CFG_MEMTEST_END:
  1141. Begin and End addresses of the area used by the
  1142. simple memory test.
  1143. - CFG_ALT_MEMTEST:
  1144. Enable an alternate, more extensive memory test.
  1145. - CFG_TFTP_LOADADDR:
  1146. Default load address for network file downloads
  1147. - CFG_LOADS_BAUD_CHANGE:
  1148. Enable temporary baudrate change while serial download
  1149. - CFG_SDRAM_BASE:
  1150. Physical start address of SDRAM. _Must_ be 0 here.
  1151. - CFG_MBIO_BASE:
  1152. Physical start address of Motherboard I/O (if using a
  1153. Cogent motherboard)
  1154. - CFG_FLASH_BASE:
  1155. Physical start address of Flash memory.
  1156. - CFG_MONITOR_BASE:
  1157. Physical start address of boot monitor code (set by
  1158. make config files to be same as the text base address
  1159. (TEXT_BASE) used when linking) - same as
  1160. CFG_FLASH_BASE when booting from flash.
  1161. - CFG_MONITOR_LEN:
  1162. Size of memory reserved for monitor code, used to
  1163. determine _at_compile_time_ (!) if the environment is
  1164. embedded within the U-Boot image, or in a separate
  1165. flash sector.
  1166. - CFG_MALLOC_LEN:
  1167. Size of DRAM reserved for malloc() use.
  1168. - CFG_BOOTMAPSZ:
  1169. Maximum size of memory mapped by the startup code of
  1170. the Linux kernel; all data that must be processed by
  1171. the Linux kernel (bd_info, boot arguments, eventually
  1172. initrd image) must be put below this limit.
  1173. - CFG_MAX_FLASH_BANKS:
  1174. Max number of Flash memory banks
  1175. - CFG_MAX_FLASH_SECT:
  1176. Max number of sectors on a Flash chip
  1177. - CFG_FLASH_ERASE_TOUT:
  1178. Timeout for Flash erase operations (in ms)
  1179. - CFG_FLASH_WRITE_TOUT:
  1180. Timeout for Flash write operations (in ms)
  1181. - CFG_FLASH_LOCK_TOUT
  1182. Timeout for Flash set sector lock bit operation (in ms)
  1183. - CFG_FLASH_UNLOCK_TOUT
  1184. Timeout for Flash clear lock bits operation (in ms)
  1185. - CFG_FLASH_PROTECTION
  1186. If defined, hardware flash sectors protection is used
  1187. instead of U-Boot software protection.
  1188. - CFG_DIRECT_FLASH_TFTP:
  1189. Enable TFTP transfers directly to flash memory;
  1190. without this option such a download has to be
  1191. performed in two steps: (1) download to RAM, and (2)
  1192. copy from RAM to flash.
  1193. The two-step approach is usually more reliable, since
  1194. you can check if the download worked before you erase
  1195. the flash, but in some situations (when sytem RAM is
  1196. too limited to allow for a tempory copy of the
  1197. downloaded image) this option may be very useful.
  1198. - CFG_FLASH_CFI:
  1199. Define if the flash driver uses extra elements in the
  1200. common flash structure for storing flash geometry
  1201. - CFG_RX_ETH_BUFFER:
  1202. Defines the number of ethernet receive buffers. On some
  1203. ethernet controllers it is recommended to set this value
  1204. to 8 or even higher (EEPRO100 or 405 EMAC), since all
  1205. buffers can be full shortly after enabling the interface
  1206. on high ethernet traffic.
  1207. Defaults to 4 if not defined.
  1208. The following definitions that deal with the placement and management
  1209. of environment data (variable area); in general, we support the
  1210. following configurations:
  1211. - CFG_ENV_IS_IN_FLASH:
  1212. Define this if the environment is in flash memory.
  1213. a) The environment occupies one whole flash sector, which is
  1214. "embedded" in the text segment with the U-Boot code. This
  1215. happens usually with "bottom boot sector" or "top boot
  1216. sector" type flash chips, which have several smaller
  1217. sectors at the start or the end. For instance, such a
  1218. layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
  1219. such a case you would place the environment in one of the
  1220. 4 kB sectors - with U-Boot code before and after it. With
  1221. "top boot sector" type flash chips, you would put the
  1222. environment in one of the last sectors, leaving a gap
  1223. between U-Boot and the environment.
  1224. - CFG_ENV_OFFSET:
  1225. Offset of environment data (variable area) to the
  1226. beginning of flash memory; for instance, with bottom boot
  1227. type flash chips the second sector can be used: the offset
  1228. for this sector is given here.
  1229. CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE.
  1230. - CFG_ENV_ADDR:
  1231. This is just another way to specify the start address of
  1232. the flash sector containing the environment (instead of
  1233. CFG_ENV_OFFSET).
  1234. - CFG_ENV_SECT_SIZE:
  1235. Size of the sector containing the environment.
  1236. b) Sometimes flash chips have few, equal sized, BIG sectors.
  1237. In such a case you don't want to spend a whole sector for
  1238. the environment.
  1239. - CFG_ENV_SIZE:
  1240. If you use this in combination with CFG_ENV_IS_IN_FLASH
  1241. and CFG_ENV_SECT_SIZE, you can specify to use only a part
  1242. of this flash sector for the environment. This saves
  1243. memory for the RAM copy of the environment.
  1244. It may also save flash memory if you decide to use this
  1245. when your environment is "embedded" within U-Boot code,
  1246. since then the remainder of the flash sector could be used
  1247. for U-Boot code. It should be pointed out that this is
  1248. STRONGLY DISCOURAGED from a robustness point of view:
  1249. updating the environment in flash makes it always
  1250. necessary to erase the WHOLE sector. If something goes
  1251. wrong before the contents has been restored from a copy in
  1252. RAM, your target system will be dead.
  1253. - CFG_ENV_ADDR_REDUND
  1254. CFG_ENV_SIZE_REDUND
  1255. These settings describe a second storage area used to hold
  1256. a redundand copy of the environment data, so that there is
  1257. a valid backup copy in case there is a power failure during
  1258. a "saveenv" operation.
  1259. BE CAREFUL! Any changes to the flash layout, and some changes to the
  1260. source code will make it necessary to adapt <board>/u-boot.lds*
  1261. accordingly!
  1262. - CFG_ENV_IS_IN_NVRAM:
  1263. Define this if you have some non-volatile memory device
  1264. (NVRAM, battery buffered SRAM) which you want to use for the
  1265. environment.
  1266. - CFG_ENV_ADDR:
  1267. - CFG_ENV_SIZE:
  1268. These two #defines are used to determin the memory area you
  1269. want to use for environment. It is assumed that this memory
  1270. can just be read and written to, without any special
  1271. provision.
  1272. BE CAREFUL! The first access to the environment happens quite early
  1273. in U-Boot initalization (when we try to get the setting of for the
  1274. console baudrate). You *MUST* have mappend your NVRAM area then, or
  1275. U-Boot will hang.
  1276. Please note that even with NVRAM we still use a copy of the
  1277. environment in RAM: we could work on NVRAM directly, but we want to
  1278. keep settings there always unmodified except somebody uses "saveenv"
  1279. to save the current settings.
  1280. - CFG_ENV_IS_IN_EEPROM:
  1281. Use this if you have an EEPROM or similar serial access
  1282. device and a driver for it.
  1283. - CFG_ENV_OFFSET:
  1284. - CFG_ENV_SIZE:
  1285. These two #defines specify the offset and size of the
  1286. environment area within the total memory of your EEPROM.
  1287. - CFG_I2C_EEPROM_ADDR:
  1288. If defined, specified the chip address of the EEPROM device.
  1289. The default address is zero.
  1290. - CFG_EEPROM_PAGE_WRITE_BITS:
  1291. If defined, the number of bits used to address bytes in a
  1292. single page in the EEPROM device. A 64 byte page, for example
  1293. would require six bits.
  1294. - CFG_EEPROM_PAGE_WRITE_DELAY_MS:
  1295. If defined, the number of milliseconds to delay between
  1296. page writes. The default is zero milliseconds.
  1297. - CFG_I2C_EEPROM_ADDR_LEN:
  1298. The length in bytes of the EEPROM memory array address. Note
  1299. that this is NOT the chip address length!
  1300. - CFG_EEPROM_SIZE:
  1301. The size in bytes of the EEPROM device.
  1302. - CFG_SPI_INIT_OFFSET
  1303. Defines offset to the initial SPI buffer area in DPRAM. The
  1304. area is used at an early stage (ROM part) if the environment
  1305. is configured to reside in the SPI EEPROM: We need a 520 byte
  1306. scratch DPRAM area. It is used between the two initialization
  1307. calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
  1308. to be a good choice since it makes it far enough from the
  1309. start of the data area as well as from the stack pointer.
  1310. Please note that the environment is read-only as long as the monitor
  1311. has been relocated to RAM and a RAM copy of the environment has been
  1312. created; also, when using EEPROM you will have to use getenv_r()
  1313. until then to read environment variables.
  1314. The environment is protected by a CRC32 checksum. Before the monitor
  1315. is relocated into RAM, as a result of a bad CRC you will be working
  1316. with the compiled-in default environment - *silently*!!! [This is
  1317. necessary, because the first environment variable we need is the
  1318. "baudrate" setting for the console - if we have a bad CRC, we don't
  1319. have any device yet where we could complain.]
  1320. Note: once the monitor has been relocated, then it will complain if
  1321. the default environment is used; a new CRC is computed as soon as you
  1322. use the "saveenv" command to store a valid environment.
  1323. Low Level (hardware related) configuration options:
  1324. ---------------------------------------------------
  1325. - CFG_CACHELINE_SIZE:
  1326. Cache Line Size of the CPU.
  1327. - CFG_DEFAULT_IMMR:
  1328. Default address of the IMMR after system reset.
  1329. Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
  1330. and RPXsuper) to be able to adjust the position of
  1331. the IMMR register after a reset.
  1332. - Floppy Disk Support:
  1333. CFG_FDC_DRIVE_NUMBER
  1334. the default drive number (default value 0)
  1335. CFG_ISA_IO_STRIDE
  1336. defines the spacing between fdc chipset registers
  1337. (default value 1)
  1338. CFG_ISA_IO_OFFSET
  1339. defines the offset of register from address. It
  1340. depends on which part of the data bus is connected to
  1341. the fdc chipset. (default value 0)
  1342. If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and
  1343. CFG_FDC_DRIVE_NUMBER are undefined, they take their
  1344. default value.
  1345. if CFG_FDC_HW_INIT is defined, then the function
  1346. fdc_hw_init() is called at the beginning of the FDC
  1347. setup. fdc_hw_init() must be provided by the board
  1348. source code. It is used to make hardware dependant
  1349. initializations.
  1350. - CFG_IMMR: Physical address of the Internal Memory Mapped
  1351. Register; DO NOT CHANGE! (11-4)
  1352. [MPC8xx systems only]
  1353. - CFG_INIT_RAM_ADDR:
  1354. Start address of memory area tha can be used for
  1355. initial data and stack; please note that this must be
  1356. writable memory that is working WITHOUT special
  1357. initialization, i. e. you CANNOT use normal RAM which
  1358. will become available only after programming the
  1359. memory controller and running certain initialization
  1360. sequences.
  1361. U-Boot uses the following memory types:
  1362. - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
  1363. - MPC824X: data cache
  1364. - PPC4xx: data cache
  1365. - CFG_GBL_DATA_OFFSET:
  1366. Offset of the initial data structure in the memory
  1367. area defined by CFG_INIT_RAM_ADDR. Usually
  1368. CFG_GBL_DATA_OFFSET is chosen such that the initial
  1369. data is located at the end of the available space
  1370. (sometimes written as (CFG_INIT_RAM_END -
  1371. CFG_INIT_DATA_SIZE), and the initial stack is just
  1372. below that area (growing from (CFG_INIT_RAM_ADDR +
  1373. CFG_GBL_DATA_OFFSET) downward.
  1374. Note:
  1375. On the MPC824X (or other systems that use the data
  1376. cache for initial memory) the address chosen for
  1377. CFG_INIT_RAM_ADDR is basically arbitrary - it must
  1378. point to an otherwise UNUSED address space between
  1379. the top of RAM and the start of the PCI space.
  1380. - CFG_SIUMCR: SIU Module Configuration (11-6)
  1381. - CFG_SYPCR: System Protection Control (11-9)
  1382. - CFG_TBSCR: Time Base Status and Control (11-26)
  1383. - CFG_PISCR: Periodic Interrupt Status and Control (11-31)
  1384. - CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
  1385. - CFG_SCCR: System Clock and reset Control Register (15-27)
  1386. - CFG_OR_TIMING_SDRAM:
  1387. SDRAM timing
  1388. - CFG_MAMR_PTA:
  1389. periodic timer for refresh
  1390. - CFG_DER: Debug Event Register (37-47)
  1391. - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM,
  1392. CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP,
  1393. CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM,
  1394. CFG_BR1_PRELIM:
  1395. Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
  1396. - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
  1397. CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM,
  1398. CFG_OR3_PRELIM, CFG_BR3_PRELIM:
  1399. Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
  1400. - CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K,
  1401. CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL:
  1402. Machine Mode Register and Memory Periodic Timer
  1403. Prescaler definitions (SDRAM timing)
  1404. - CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]:
  1405. enable I2C microcode relocation patch (MPC8xx);
  1406. define relocation offset in DPRAM [DSP2]
  1407. - CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]:
  1408. enable SPI microcode relocation patch (MPC8xx);
  1409. define relocation offset in DPRAM [SCC4]
  1410. - CFG_USE_OSCCLK:
  1411. Use OSCM clock mode on MBX8xx board. Be careful,
  1412. wrong setting might damage your board. Read
  1413. doc/README.MBX before setting this variable!
  1414. - CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
  1415. Offset of the bootmode word in DPRAM used by post
  1416. (Power On Self Tests). This definition overrides
  1417. #define'd default value in commproc.h resp.
  1418. cpm_8260.h.
  1419. - CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB,
  1420. CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL,
  1421. CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS,
  1422. CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB,
  1423. CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
  1424. CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL,
  1425. CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE,
  1426. CFG_POCMR2_MASK_ATTRIB: (MPC826x only)
  1427. Overrides the default PCI memory map in cpu/mpc8260/pci.c if set.
  1428. Building the Software:
  1429. ======================
  1430. Building U-Boot has been tested in native PPC environments (on a
  1431. PowerBook G3 running LinuxPPC 2000) and in cross environments
  1432. (running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and
  1433. NetBSD 1.5 on x86).
  1434. If you are not using a native PPC environment, it is assumed that you
  1435. have the GNU cross compiling tools available in your path and named
  1436. with a prefix of "powerpc-linux-". If this is not the case, (e.g. if
  1437. you are using Monta Vista's Hard Hat Linux CDK 1.2) you must change
  1438. the definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU,
  1439. change it to:
  1440. CROSS_COMPILE = ppc_4xx-
  1441. U-Boot is intended to be simple to build. After installing the
  1442. sources you must configure U-Boot for one specific board type. This
  1443. is done by typing:
  1444. make NAME_config
  1445. where "NAME_config" is the name of one of the existing
  1446. configurations; the following names are supported:
  1447. ADCIOP_config GTH_config TQM850L_config
  1448. ADS860_config IP860_config TQM855L_config
  1449. AR405_config IVML24_config TQM860L_config
  1450. CANBT_config IVMS8_config WALNUT405_config
  1451. CPCI405_config LANTEC_config cogent_common_config
  1452. CPCIISER4_config MBX_config cogent_mpc8260_config
  1453. CU824_config MBX860T_config cogent_mpc8xx_config
  1454. ESTEEM192E_config RPXlite_config hermes_config
  1455. ETX094_config RPXsuper_config hymod_config
  1456. FADS823_config SM850_config lwmon_config
  1457. FADS850SAR_config SPD823TS_config pcu_e_config
  1458. FADS860T_config SXNI855T_config rsdproto_config
  1459. FPS850L_config Sandpoint8240_config sbc8260_config
  1460. GENIETV_config TQM823L_config PIP405_config
  1461. GEN860T_config EBONY_config FPS860L_config
  1462. ELPT860_config cmi_mpc5xx_config NETVIA_config
  1463. at91rm9200dk_config omap1510inn_config MPC8260ADS_config
  1464. Note: for some board special configuration names may exist; check if
  1465. additional information is available from the board vendor; for
  1466. instance, the TQM8xxL systems run normally at 50 MHz and use a
  1467. SCC for 10baseT ethernet; there are also systems with 80 MHz
  1468. CPU clock, and an optional Fast Ethernet module is available
  1469. for CPU's with FEC. You can select such additional "features"
  1470. when chosing the configuration, i. e.
  1471. make TQM860L_config
  1472. - will configure for a plain TQM860L, i. e. 50MHz, no FEC
  1473. make TQM860L_FEC_config
  1474. - will configure for a TQM860L at 50MHz with FEC for ethernet
  1475. make TQM860L_80MHz_config
  1476. - will configure for a TQM860L at 80 MHz, with normal 10baseT
  1477. interface
  1478. make TQM860L_FEC_80MHz_config
  1479. - will configure for a TQM860L at 80 MHz with FEC for ethernet
  1480. make TQM823L_LCD_config
  1481. - will configure for a TQM823L with U-Boot console on LCD
  1482. make TQM823L_LCD_80MHz_config
  1483. - will configure for a TQM823L at 80 MHz with U-Boot console on LCD
  1484. etc.
  1485. Finally, type "make all", and you should get some working U-Boot
  1486. images ready for downlod to / installation on your system:
  1487. - "u-boot.bin" is a raw binary image
  1488. - "u-boot" is an image in ELF binary format
  1489. - "u-boot.srec" is in Motorola S-Record format
  1490. Please be aware that the Makefiles assume you are using GNU make, so
  1491. for instance on NetBSD you might need to use "gmake" instead of
  1492. native "make".
  1493. If the system board that you have is not listed, then you will need
  1494. to port U-Boot to your hardware platform. To do this, follow these
  1495. steps:
  1496. 1. Add a new configuration option for your board to the toplevel
  1497. "Makefile" and to the "MAKEALL" script, using the existing
  1498. entries as examples. Note that here and at many other places
  1499. boards and other names are listed alphabetically sorted. Please
  1500. keep this order.
  1501. 2. Create a new directory to hold your board specific code. Add any
  1502. files you need. In your board directory, you will need at least
  1503. the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
  1504. 3. Create a new configuration file "include/configs/<board>.h" for
  1505. your board
  1506. 3. If you're porting U-Boot to a new CPU, then also create a new
  1507. directory to hold your CPU specific code. Add any files you need.
  1508. 4. Run "make <board>_config" with your new name.
  1509. 5. Type "make", and you should get a working "u-boot.srec" file
  1510. to be installed on your target system.
  1511. 6. Debug and solve any problems that might arise.
  1512. [Of course, this last step is much harder than it sounds.]
  1513. Testing of U-Boot Modifications, Ports to New Hardware, etc.:
  1514. ==============================================================
  1515. If you have modified U-Boot sources (for instance added a new board
  1516. or support for new devices, a new CPU, etc.) you are expected to
  1517. provide feedback to the other developers. The feedback normally takes
  1518. the form of a "patch", i. e. a context diff against a certain (latest
  1519. official or latest in CVS) version of U-Boot sources.
  1520. But before you submit such a patch, please verify that your modifi-
  1521. cation did not break existing code. At least make sure that *ALL* of
  1522. the supported boards compile WITHOUT ANY compiler warnings. To do so,
  1523. just run the "MAKEALL" script, which will configure and build U-Boot
  1524. for ALL supported system. Be warned, this will take a while. You can
  1525. select which (cross) compiler to use py passing a `CROSS_COMPILE'
  1526. environment variable to the script, i. e. to use the cross tools from
  1527. MontaVista's Hard Hat Linux you can type
  1528. CROSS_COMPILE=ppc_8xx- MAKEALL
  1529. or to build on a native PowerPC system you can type
  1530. CROSS_COMPILE=' ' MAKEALL
  1531. See also "U-Boot Porting Guide" below.
  1532. Monitor Commands - Overview:
  1533. ============================
  1534. go - start application at address 'addr'
  1535. run - run commands in an environment variable
  1536. bootm - boot application image from memory
  1537. bootp - boot image via network using BootP/TFTP protocol
  1538. tftpboot- boot image via network using TFTP protocol
  1539. and env variables "ipaddr" and "serverip"
  1540. (and eventually "gatewayip")
  1541. rarpboot- boot image via network using RARP/TFTP protocol
  1542. diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
  1543. loads - load S-Record file over serial line
  1544. loadb - load binary file over serial line (kermit mode)
  1545. md - memory display
  1546. mm - memory modify (auto-incrementing)
  1547. nm - memory modify (constant address)
  1548. mw - memory write (fill)
  1549. cp - memory copy
  1550. cmp - memory compare
  1551. crc32 - checksum calculation
  1552. imd - i2c memory display
  1553. imm - i2c memory modify (auto-incrementing)
  1554. inm - i2c memory modify (constant address)
  1555. imw - i2c memory write (fill)
  1556. icrc32 - i2c checksum calculation
  1557. iprobe - probe to discover valid I2C chip addresses
  1558. iloop - infinite loop on address range
  1559. isdram - print SDRAM configuration information
  1560. sspi - SPI utility commands
  1561. base - print or set address offset
  1562. printenv- print environment variables
  1563. setenv - set environment variables
  1564. saveenv - save environment variables to persistent storage
  1565. protect - enable or disable FLASH write protection
  1566. erase - erase FLASH memory
  1567. flinfo - print FLASH memory information
  1568. bdinfo - print Board Info structure
  1569. iminfo - print header information for application image
  1570. coninfo - print console devices and informations
  1571. ide - IDE sub-system
  1572. loop - infinite loop on address range
  1573. mtest - simple RAM test
  1574. icache - enable or disable instruction cache
  1575. dcache - enable or disable data cache
  1576. reset - Perform RESET of the CPU
  1577. echo - echo args to console
  1578. version - print monitor version
  1579. help - print online help
  1580. ? - alias for 'help'
  1581. Monitor Commands - Detailed Description:
  1582. ========================================
  1583. TODO.
  1584. For now: just type "help <command>".
  1585. Environment Variables:
  1586. ======================
  1587. U-Boot supports user configuration using Environment Variables which
  1588. can be made persistent by saving to Flash memory.
  1589. Environment Variables are set using "setenv", printed using
  1590. "printenv", and saved to Flash using "saveenv". Using "setenv"
  1591. without a value can be used to delete a variable from the
  1592. environment. As long as you don't save the environment you are
  1593. working with an in-memory copy. In case the Flash area containing the
  1594. environment is erased by accident, a default environment is provided.
  1595. Some configuration options can be set using Environment Variables:
  1596. baudrate - see CONFIG_BAUDRATE
  1597. bootdelay - see CONFIG_BOOTDELAY
  1598. bootcmd - see CONFIG_BOOTCOMMAND
  1599. bootargs - Boot arguments when booting an RTOS image
  1600. bootfile - Name of the image to load with TFTP
  1601. autoload - if set to "no" (any string beginning with 'n'),
  1602. "bootp" will just load perform a lookup of the
  1603. configuration from the BOOTP server, but not try to
  1604. load any image using TFTP
  1605. autostart - if set to "yes", an image loaded using the "bootp",
  1606. "rarpboot", "tftpboot" or "diskboot" commands will
  1607. be automatically started (by internally calling
  1608. "bootm")
  1609. If set to "no", a standalone image passed to the
  1610. "bootm" command will be copied to the load address
  1611. (and eventually uncompressed), but NOT be started.
  1612. This can be used to load and uncompress arbitrary
  1613. data.
  1614. initrd_high - restrict positioning of initrd images:
  1615. If this variable is not set, initrd images will be
  1616. copied to the highest possible address in RAM; this
  1617. is usually what you want since it allows for
  1618. maximum initrd size. If for some reason you want to
  1619. make sure that the initrd image is loaded below the
  1620. CFG_BOOTMAPSZ limit, you can set this environment
  1621. variable to a value of "no" or "off" or "0".
  1622. Alternatively, you can set it to a maximum upper
  1623. address to use (U-Boot will still check that it
  1624. does not overwrite the U-Boot stack and data).
  1625. For instance, when you have a system with 16 MB
  1626. RAM, and want to reseve 4 MB from use by Linux,
  1627. you can do this by adding "mem=12M" to the value of
  1628. the "bootargs" variable. However, now you must make
  1629. sure, that the initrd image is placed in the first
  1630. 12 MB as well - this can be done with
  1631. setenv initrd_high 00c00000
  1632. If you set initrd_high to 0xFFFFFFFF, this is an
  1633. indication to U-Boot that all addresses are legal
  1634. for the Linux kernel, including addresses in flash
  1635. memory. In this case U-Boot will NOT COPY the
  1636. ramdisk at all. This may be useful to reduce the
  1637. boot time on your system, but requires that this
  1638. feature is supported by your Linux kernel.
  1639. ipaddr - IP address; needed for tftpboot command
  1640. loadaddr - Default load address for commands like "bootp",
  1641. "rarpboot", "tftpboot", "loadb" or "diskboot"
  1642. loads_echo - see CONFIG_LOADS_ECHO
  1643. serverip - TFTP server IP address; needed for tftpboot command
  1644. bootretry - see CONFIG_BOOT_RETRY_TIME
  1645. bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
  1646. bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
  1647. The following environment variables may be used and automatically
  1648. updated by the network boot commands ("bootp" and "rarpboot"),
  1649. depending the information provided by your boot server:
  1650. bootfile - see above
  1651. dnsip - IP address of your Domain Name Server
  1652. dnsip2 - IP address of your secondary Domain Name Server
  1653. gatewayip - IP address of the Gateway (Router) to use
  1654. hostname - Target hostname
  1655. ipaddr - see above
  1656. netmask - Subnet Mask
  1657. rootpath - Pathname of the root filesystem on the NFS server
  1658. serverip - see above
  1659. There are two special Environment Variables:
  1660. serial# - contains hardware identification information such
  1661. as type string and/or serial number
  1662. ethaddr - Ethernet address
  1663. These variables can be set only once (usually during manufacturing of
  1664. the board). U-Boot refuses to delete or overwrite these variables
  1665. once they have been set once.
  1666. Further special Environment Variables:
  1667. ver - Contains the U-Boot version string as printed
  1668. with the "version" command. This variable is
  1669. readonly (see CONFIG_VERSION_VARIABLE).
  1670. Please note that changes to some configuration parameters may take
  1671. only effect after the next boot (yes, that's just like Windoze :-).
  1672. Command Line Parsing:
  1673. =====================
  1674. There are two different command line parsers available with U-Boot:
  1675. the old "simple" one, and the much more pwerful "hush" shell:
  1676. Old, simple command line parser:
  1677. --------------------------------
  1678. - supports environment variables (through setenv / saveenv commands)
  1679. - several commands on one line, separated by ';'
  1680. - variable substitution using "... $(name) ..." syntax
  1681. - special characters ('$', ';') can be escaped by prefixing with '\',
  1682. for example:
  1683. setenv bootcmd bootm \$(address)
  1684. - You can also escape text by enclosing in single apostrophes, for example:
  1685. setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
  1686. Hush shell:
  1687. -----------
  1688. - similar to Bourne shell, with control structures like
  1689. if...then...else...fi, for...do...done; while...do...done,
  1690. until...do...done, ...
  1691. - supports environment ("global") variables (through setenv / saveenv
  1692. commands) and local shell variables (through standard shell syntax
  1693. "name=value"); only environment variables can be used with "run"
  1694. command
  1695. General rules:
  1696. --------------
  1697. (1) If a command line (or an environment variable executed by a "run"
  1698. command) contains several commands separated by semicolon, and
  1699. one of these commands fails, then the remaining commands will be
  1700. executed anyway.
  1701. (2) If you execute several variables with one call to run (i. e.
  1702. calling run with a list af variables as arguments), any failing
  1703. command will cause "run" to terminate, i. e. the remaining
  1704. variables are not executed.
  1705. Note for Redundant Ethernet Interfaces:
  1706. =======================================
  1707. Some boards come with redundand ethernet interfaces; U-Boot supports
  1708. such configurations and is capable of automatic selection of a
  1709. "working" interface when needed. MAC assignemnt works as follows:
  1710. Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
  1711. MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
  1712. "eth1addr" (=>eth1), "eth2addr", ...
  1713. If the network interface stores some valid MAC address (for instance
  1714. in SROM), this is used as default address if there is NO correspon-
  1715. ding setting in the environment; if the corresponding environment
  1716. variable is set, this overrides the settings in the card; that means:
  1717. o If the SROM has a valid MAC address, and there is no address in the
  1718. environment, the SROM's address is used.
  1719. o If there is no valid address in the SROM, and a definition in the
  1720. environment exists, then the value from the environment variable is
  1721. used.
  1722. o If both the SROM and the environment contain a MAC address, and
  1723. both addresses are the same, this MAC address is used.
  1724. o If both the SROM and the environment contain a MAC address, and the
  1725. addresses differ, the value from the environment is used and a
  1726. warning is printed.
  1727. o If neither SROM nor the environment contain a MAC address, an error
  1728. is raised.
  1729. Image Formats:
  1730. ==============
  1731. The "boot" commands of this monitor operate on "image" files which
  1732. can be basicly anything, preceeded by a special header; see the
  1733. definitions in include/image.h for details; basicly, the header
  1734. defines the following image properties:
  1735. * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
  1736. 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
  1737. LynxOS, pSOS, QNX, RTEMS, ARTOS;
  1738. Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS).
  1739. * Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
  1740. IA64, MIPS, MIPS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
  1741. Currently supported: PowerPC).
  1742. * Compression Type (Provisions for uncompressed, gzip, bzip2;
  1743. Currently supported: uncompressed, gzip).
  1744. * Load Address
  1745. * Entry Point
  1746. * Image Name
  1747. * Image Timestamp
  1748. The header is marked by a special Magic Number, and both the header
  1749. and the data portions of the image are secured against corruption by
  1750. CRC32 checksums.
  1751. Linux Support:
  1752. ==============
  1753. Although U-Boot should support any OS or standalone application
  1754. easily, Linux has always been in the focus during the design of
  1755. U-Boot.
  1756. U-Boot includes many features that so far have been part of some
  1757. special "boot loader" code within the Linux kernel. Also, any
  1758. "initrd" images to be used are no longer part of one big Linux image;
  1759. instead, kernel and "initrd" are separate images. This implementation
  1760. serves serveral purposes:
  1761. - the same features can be used for other OS or standalone
  1762. applications (for instance: using compressed images to reduce the
  1763. Flash memory footprint)
  1764. - it becomes much easier to port new Linux kernel versions because
  1765. lots of low-level, hardware dependend stuff are done by U-Boot
  1766. - the same Linux kernel image can now be used with different "initrd"
  1767. images; of course this also means that different kernel images can
  1768. be run with the same "initrd". This makes testing easier (you don't
  1769. have to build a new "zImage.initrd" Linux image when you just
  1770. change a file in your "initrd"). Also, a field-upgrade of the
  1771. software is easier now.
  1772. Linux HOWTO:
  1773. ============
  1774. Porting Linux to U-Boot based systems:
  1775. ---------------------------------------
  1776. U-Boot cannot save you from doing all the necessary modifications to
  1777. configure the Linux device drivers for use with your target hardware
  1778. (no, we don't intend to provide a full virtual machine interface to
  1779. Linux :-).
  1780. But now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
  1781. Just make sure your machine specific header file (for instance
  1782. include/asm-ppc/tqm8xx.h) includes the same definition of the Board
  1783. Information structure as we define in include/u-boot.h, and make
  1784. sure that your definition of IMAP_ADDR uses the same value as your
  1785. U-Boot configuration in CFG_IMMR.
  1786. Configuring the Linux kernel:
  1787. -----------------------------
  1788. No specific requirements for U-Boot. Make sure you have some root
  1789. device (initial ramdisk, NFS) for your target system.
  1790. Building a Linux Image:
  1791. -----------------------
  1792. With U-Boot, "normal" build targets like "zImage" or "bzImage" are
  1793. not used. If you use recent kernel source, a new build target
  1794. "uImage" will exist which automatically builds an image usable by
  1795. U-Boot. Most older kernels also have support for a "pImage" target,
  1796. which was introduced for our predecessor project PPCBoot and uses a
  1797. 100% compatible format.
  1798. Example:
  1799. make TQM850L_config
  1800. make oldconfig
  1801. make dep
  1802. make uImage
  1803. The "uImage" build target uses a special tool (in 'tools/mkimage') to
  1804. encapsulate a compressed Linux kernel image with header information,
  1805. CRC32 checksum etc. for use with U-Boot. This is what we are doing:
  1806. * build a standard "vmlinux" kernel image (in ELF binary format):
  1807. * convert the kernel into a raw binary image:
  1808. ${CROSS_COMPILE}-objcopy -O binary \
  1809. -R .note -R .comment \
  1810. -S vmlinux linux.bin
  1811. * compress the binary image:
  1812. gzip -9 linux.bin
  1813. * package compressed binary image for U-Boot:
  1814. mkimage -A ppc -O linux -T kernel -C gzip \
  1815. -a 0 -e 0 -n "Linux Kernel Image" \
  1816. -d linux.bin.gz uImage
  1817. The "mkimage" tool can also be used to create ramdisk images for use
  1818. with U-Boot, either separated from the Linux kernel image, or
  1819. combined into one file. "mkimage" encapsulates the images with a 64
  1820. byte header containing information about target architecture,
  1821. operating system, image type, compression method, entry points, time
  1822. stamp, CRC32 checksums, etc.
  1823. "mkimage" can be called in two ways: to verify existing images and
  1824. print the header information, or to build new images.
  1825. In the first form (with "-l" option) mkimage lists the information
  1826. contained in the header of an existing U-Boot image; this includes
  1827. checksum verification:
  1828. tools/mkimage -l image
  1829. -l ==> list image header information
  1830. The second form (with "-d" option) is used to build a U-Boot image
  1831. from a "data file" which is used as image payload:
  1832. tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
  1833. -n name -d data_file image
  1834. -A ==> set architecture to 'arch'
  1835. -O ==> set operating system to 'os'
  1836. -T ==> set image type to 'type'
  1837. -C ==> set compression type 'comp'
  1838. -a ==> set load address to 'addr' (hex)
  1839. -e ==> set entry point to 'ep' (hex)
  1840. -n ==> set image name to 'name'
  1841. -d ==> use image data from 'datafile'
  1842. Right now, all Linux kernels use the same load address (0x00000000),
  1843. but the entry point address depends on the kernel version:
  1844. - 2.2.x kernels have the entry point at 0x0000000C,
  1845. - 2.3.x and later kernels have the entry point at 0x00000000.
  1846. So a typical call to build a U-Boot image would read:
  1847. -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
  1848. > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
  1849. > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
  1850. > examples/uImage.TQM850L
  1851. Image Name: 2.4.4 kernel for TQM850L
  1852. Created: Wed Jul 19 02:34:59 2000
  1853. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  1854. Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
  1855. Load Address: 0x00000000
  1856. Entry Point: 0x00000000
  1857. To verify the contents of the image (or check for corruption):
  1858. -> tools/mkimage -l examples/uImage.TQM850L
  1859. Image Name: 2.4.4 kernel for TQM850L
  1860. Created: Wed Jul 19 02:34:59 2000
  1861. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  1862. Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
  1863. Load Address: 0x00000000
  1864. Entry Point: 0x00000000
  1865. NOTE: for embedded systems where boot time is critical you can trade
  1866. speed for memory and install an UNCOMPRESSED image instead: this
  1867. needs more space in Flash, but boots much faster since it does not
  1868. need to be uncompressed:
  1869. -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
  1870. -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
  1871. > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
  1872. > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
  1873. > examples/uImage.TQM850L-uncompressed
  1874. Image Name: 2.4.4 kernel for TQM850L
  1875. Created: Wed Jul 19 02:34:59 2000
  1876. Image Type: PowerPC Linux Kernel Image (uncompressed)
  1877. Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
  1878. Load Address: 0x00000000
  1879. Entry Point: 0x00000000
  1880. Similar you can build U-Boot images from a 'ramdisk.image.gz' file
  1881. when your kernel is intended to use an initial ramdisk:
  1882. -> tools/mkimage -n 'Simple Ramdisk Image' \
  1883. > -A ppc -O linux -T ramdisk -C gzip \
  1884. > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
  1885. Image Name: Simple Ramdisk Image
  1886. Created: Wed Jan 12 14:01:50 2000
  1887. Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
  1888. Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
  1889. Load Address: 0x00000000
  1890. Entry Point: 0x00000000
  1891. Installing a Linux Image:
  1892. -------------------------
  1893. To downloading a U-Boot image over the serial (console) interface,
  1894. you must convert the image to S-Record format:
  1895. objcopy -I binary -O srec examples/image examples/image.srec
  1896. The 'objcopy' does not understand the information in the U-Boot
  1897. image header, so the resulting S-Record file will be relative to
  1898. address 0x00000000. To load it to a given address, you need to
  1899. specify the target address as 'offset' parameter with the 'loads'
  1900. command.
  1901. Example: install the image to address 0x40100000 (which on the
  1902. TQM8xxL is in the first Flash bank):
  1903. => erase 40100000 401FFFFF
  1904. .......... done
  1905. Erased 8 sectors
  1906. => loads 40100000
  1907. ## Ready for S-Record download ...
  1908. ~>examples/image.srec
  1909. 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
  1910. ...
  1911. 15989 15990 15991 15992
  1912. [file transfer complete]
  1913. [connected]
  1914. ## Start Addr = 0x00000000
  1915. You can check the success of the download using the 'iminfo' command;
  1916. this includes a checksum verification so you can be sure no data
  1917. corruption happened:
  1918. => imi 40100000
  1919. ## Checking Image at 40100000 ...
  1920. Image Name: 2.2.13 for initrd on TQM850L
  1921. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  1922. Data Size: 335725 Bytes = 327 kB = 0 MB
  1923. Load Address: 00000000
  1924. Entry Point: 0000000c
  1925. Verifying Checksum ... OK
  1926. Boot Linux:
  1927. -----------
  1928. The "bootm" command is used to boot an application that is stored in
  1929. memory (RAM or Flash). In case of a Linux kernel image, the contents
  1930. of the "bootargs" environment variable is passed to the kernel as
  1931. parameters. You can check and modify this variable using the
  1932. "printenv" and "setenv" commands:
  1933. => printenv bootargs
  1934. bootargs=root=/dev/ram
  1935. => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
  1936. => printenv bootargs
  1937. bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
  1938. => bootm 40020000
  1939. ## Booting Linux kernel at 40020000 ...
  1940. Image Name: 2.2.13 for NFS on TQM850L
  1941. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  1942. Data Size: 381681 Bytes = 372 kB = 0 MB
  1943. Load Address: 00000000
  1944. Entry Point: 0000000c
  1945. Verifying Checksum ... OK
  1946. Uncompressing Kernel Image ... OK
  1947. 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
  1948. Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
  1949. time_init: decrementer frequency = 187500000/60
  1950. Calibrating delay loop... 49.77 BogoMIPS
  1951. Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
  1952. ...
  1953. If you want to boot a Linux kernel with initial ram disk, you pass
  1954. the memory addreses of both the kernel and the initrd image (PPBCOOT
  1955. format!) to the "bootm" command:
  1956. => imi 40100000 40200000
  1957. ## Checking Image at 40100000 ...
  1958. Image Name: 2.2.13 for initrd on TQM850L
  1959. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  1960. Data Size: 335725 Bytes = 327 kB = 0 MB
  1961. Load Address: 00000000
  1962. Entry Point: 0000000c
  1963. Verifying Checksum ... OK
  1964. ## Checking Image at 40200000 ...
  1965. Image Name: Simple Ramdisk Image
  1966. Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
  1967. Data Size: 566530 Bytes = 553 kB = 0 MB
  1968. Load Address: 00000000
  1969. Entry Point: 00000000
  1970. Verifying Checksum ... OK
  1971. => bootm 40100000 40200000
  1972. ## Booting Linux kernel at 40100000 ...
  1973. Image Name: 2.2.13 for initrd on TQM850L
  1974. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  1975. Data Size: 335725 Bytes = 327 kB = 0 MB
  1976. Load Address: 00000000
  1977. Entry Point: 0000000c
  1978. Verifying Checksum ... OK
  1979. Uncompressing Kernel Image ... OK
  1980. ## Loading RAMDisk Image at 40200000 ...
  1981. Image Name: Simple Ramdisk Image
  1982. Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
  1983. Data Size: 566530 Bytes = 553 kB = 0 MB
  1984. Load Address: 00000000
  1985. Entry Point: 00000000
  1986. Verifying Checksum ... OK
  1987. Loading Ramdisk ... OK
  1988. 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
  1989. Boot arguments: root=/dev/ram
  1990. time_init: decrementer frequency = 187500000/60
  1991. Calibrating delay loop... 49.77 BogoMIPS
  1992. ...
  1993. RAMDISK: Compressed image found at block 0
  1994. VFS: Mounted root (ext2 filesystem).
  1995. bash#
  1996. More About U-Boot Image Types:
  1997. ------------------------------
  1998. U-Boot supports the following image types:
  1999. "Standalone Programs" are directly runnable in the environment
  2000. provided by U-Boot; it is expected that (if they behave
  2001. well) you can continue to work in U-Boot after return from
  2002. the Standalone Program.
  2003. "OS Kernel Images" are usually images of some Embedded OS which
  2004. will take over control completely. Usually these programs
  2005. will install their own set of exception handlers, device
  2006. drivers, set up the MMU, etc. - this means, that you cannot
  2007. expect to re-enter U-Boot except by resetting the CPU.
  2008. "RAMDisk Images" are more or less just data blocks, and their
  2009. parameters (address, size) are passed to an OS kernel that is
  2010. being started.
  2011. "Multi-File Images" contain several images, typically an OS
  2012. (Linux) kernel image and one or more data images like
  2013. RAMDisks. This construct is useful for instance when you want
  2014. to boot over the network using BOOTP etc., where the boot
  2015. server provides just a single image file, but you want to get
  2016. for instance an OS kernel and a RAMDisk image.
  2017. "Multi-File Images" start with a list of image sizes, each
  2018. image size (in bytes) specified by an "uint32_t" in network
  2019. byte order. This list is terminated by an "(uint32_t)0".
  2020. Immediately after the terminating 0 follow the images, one by
  2021. one, all aligned on "uint32_t" boundaries (size rounded up to
  2022. a multiple of 4 bytes).
  2023. "Firmware Images" are binary images containing firmware (like
  2024. U-Boot or FPGA images) which usually will be programmed to
  2025. flash memory.
  2026. "Script files" are command sequences that will be executed by
  2027. U-Boot's command interpreter; this feature is especially
  2028. useful when you configure U-Boot to use a real shell (hush)
  2029. as command interpreter.
  2030. Standalone HOWTO:
  2031. =================
  2032. One of the features of U-Boot is that you can dynamically load and
  2033. run "standalone" applications, which can use some resources of
  2034. U-Boot like console I/O functions or interrupt services.
  2035. Two simple examples are included with the sources:
  2036. "Hello World" Demo:
  2037. -------------------
  2038. 'examples/hello_world.c' contains a small "Hello World" Demo
  2039. application; it is automatically compiled when you build U-Boot.
  2040. It's configured to run at address 0x00040004, so you can play with it
  2041. like that:
  2042. => loads
  2043. ## Ready for S-Record download ...
  2044. ~>examples/hello_world.srec
  2045. 1 2 3 4 5 6 7 8 9 10 11 ...
  2046. [file transfer complete]
  2047. [connected]
  2048. ## Start Addr = 0x00040004
  2049. => go 40004 Hello World! This is a test.
  2050. ## Starting application at 0x00040004 ...
  2051. Hello World
  2052. argc = 7
  2053. argv[0] = "40004"
  2054. argv[1] = "Hello"
  2055. argv[2] = "World!"
  2056. argv[3] = "This"
  2057. argv[4] = "is"
  2058. argv[5] = "a"
  2059. argv[6] = "test."
  2060. argv[7] = "<NULL>"
  2061. Hit any key to exit ...
  2062. ## Application terminated, rc = 0x0
  2063. Another example, which demonstrates how to register a CPM interrupt
  2064. handler with the U-Boot code, can be found in 'examples/timer.c'.
  2065. Here, a CPM timer is set up to generate an interrupt every second.
  2066. The interrupt service routine is trivial, just printing a '.'
  2067. character, but this is just a demo program. The application can be
  2068. controlled by the following keys:
  2069. ? - print current values og the CPM Timer registers
  2070. b - enable interrupts and start timer
  2071. e - stop timer and disable interrupts
  2072. q - quit application
  2073. => loads
  2074. ## Ready for S-Record download ...
  2075. ~>examples/timer.srec
  2076. 1 2 3 4 5 6 7 8 9 10 11 ...
  2077. [file transfer complete]
  2078. [connected]
  2079. ## Start Addr = 0x00040004
  2080. => go 40004
  2081. ## Starting application at 0x00040004 ...
  2082. TIMERS=0xfff00980
  2083. Using timer 1
  2084. tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
  2085. Hit 'b':
  2086. [q, b, e, ?] Set interval 1000000 us
  2087. Enabling timer
  2088. Hit '?':
  2089. [q, b, e, ?] ........
  2090. tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
  2091. Hit '?':
  2092. [q, b, e, ?] .
  2093. tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
  2094. Hit '?':
  2095. [q, b, e, ?] .
  2096. tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
  2097. Hit '?':
  2098. [q, b, e, ?] .
  2099. tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
  2100. Hit 'e':
  2101. [q, b, e, ?] ...Stopping timer
  2102. Hit 'q':
  2103. [q, b, e, ?] ## Application terminated, rc = 0x0
  2104. Minicom warning:
  2105. ================
  2106. Over time, many people have reported problems when trying to used the
  2107. "minicom" terminal emulation program for serial download. I (wd)
  2108. consider minicom to be broken, and recommend not to use it. Under
  2109. Unix, I recommend to use C-Kermit for general purpose use (and
  2110. especially for kermit binary protocol download ("loadb" command), and
  2111. use "cu" for S-Record download ("loads" command).
  2112. Nevertheless, if you absolutely want to use it try adding this
  2113. configuration to your "File transfer protocols" section:
  2114. Name Program Name U/D FullScr IO-Red. Multi
  2115. X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
  2116. Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
  2117. NetBSD Notes:
  2118. =============
  2119. Starting at version 0.9.2, U-Boot supports NetBSD both as host
  2120. (build U-Boot) and target system (boots NetBSD/mpc8xx).
  2121. Building requires a cross environment; it is known to work on
  2122. NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
  2123. need gmake since the Makefiles are not compatible with BSD make).
  2124. Note that the cross-powerpc package does not install include files;
  2125. attempting to build U-Boot will fail because <machine/ansi.h> is
  2126. missing. This file has to be installed and patched manually:
  2127. # cd /usr/pkg/cross/powerpc-netbsd/include
  2128. # mkdir powerpc
  2129. # ln -s powerpc machine
  2130. # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
  2131. # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
  2132. Native builds *don't* work due to incompatibilities between native
  2133. and U-Boot include files.
  2134. Booting assumes that (the first part of) the image booted is a
  2135. stage-2 loader which in turn loads and then invokes the kernel
  2136. proper. Loader sources will eventually appear in the NetBSD source
  2137. tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
  2138. meantime, send mail to bruno@exet-ag.de and/or wd@denx.de for
  2139. details.
  2140. Implementation Internals:
  2141. =========================
  2142. The following is not intended to be a complete description of every
  2143. implementation detail. However, it should help to understand the
  2144. inner workings of U-Boot and make it easier to port it to custom
  2145. hardware.
  2146. Initial Stack, Global Data:
  2147. ---------------------------
  2148. The implementation of U-Boot is complicated by the fact that U-Boot
  2149. starts running out of ROM (flash memory), usually without access to
  2150. system RAM (because the memory controller is not initialized yet).
  2151. This means that we don't have writable Data or BSS segments, and BSS
  2152. is not initialized as zero. To be able to get a C environment working
  2153. at all, we have to allocate at least a minimal stack. Implementation
  2154. options for this are defined and restricted by the CPU used: Some CPU
  2155. models provide on-chip memory (like the IMMR area on MPC8xx and
  2156. MPC826x processors), on others (parts of) the data cache can be
  2157. locked as (mis-) used as memory, etc.
  2158. Chris Hallinan posted a good summy of these issues to the
  2159. u-boot-users mailing list:
  2160. Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
  2161. From: "Chris Hallinan" <clh@net1plus.com>
  2162. Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
  2163. ...
  2164. Correct me if I'm wrong, folks, but the way I understand it
  2165. is this: Using DCACHE as initial RAM for Stack, etc, does not
  2166. require any physical RAM backing up the cache. The cleverness
  2167. is that the cache is being used as a temporary supply of
  2168. necessary storage before the SDRAM controller is setup. It's
  2169. beyond the scope of this list to expain the details, but you
  2170. can see how this works by studying the cache architecture and
  2171. operation in the architecture and processor-specific manuals.
  2172. OCM is On Chip Memory, which I believe the 405GP has 4K. It
  2173. is another option for the system designer to use as an
  2174. initial stack/ram area prior to SDRAM being available. Either
  2175. option should work for you. Using CS 4 should be fine if your
  2176. board designers haven't used it for something that would
  2177. cause you grief during the initial boot! It is frequently not
  2178. used.
  2179. CFG_INIT_RAM_ADDR should be somewhere that won't interfere
  2180. with your processor/board/system design. The default value
  2181. you will find in any recent u-boot distribution in
  2182. Walnut405.h should work for you. I'd set it to a value larger
  2183. than your SDRAM module. If you have a 64MB SDRAM module, set
  2184. it above 400_0000. Just make sure your board has no resources
  2185. that are supposed to respond to that address! That code in
  2186. start.S has been around a while and should work as is when
  2187. you get the config right.
  2188. -Chris Hallinan
  2189. DS4.COM, Inc.
  2190. It is essential to remember this, since it has some impact on the C
  2191. code for the initialization procedures:
  2192. * Initialized global data (data segment) is read-only. Do not attempt
  2193. to write it.
  2194. * Do not use any unitialized global data (or implicitely initialized
  2195. as zero data - BSS segment) at all - this is undefined, initiali-
  2196. zation is performed later (when relocationg to RAM).
  2197. * Stack space is very limited. Avoid big data buffers or things like
  2198. that.
  2199. Having only the stack as writable memory limits means we cannot use
  2200. normal global data to share information beween the code. But it
  2201. turned out that the implementation of U-Boot can be greatly
  2202. simplified by making a global data structure (gd_t) available to all
  2203. functions. We could pass a pointer to this data as argument to _all_
  2204. functions, but this would bloat the code. Instead we use a feature of
  2205. the GCC compiler (Global Register Variables) to share the data: we
  2206. place a pointer (gd) to the global data into a register which we
  2207. reserve for this purpose.
  2208. When chosing a register for such a purpose we are restricted by the
  2209. relevant (E)ABI specifications for the current architecture, and by
  2210. GCC's implementation.
  2211. For PowerPC, the following registers have specific use:
  2212. R1: stack pointer
  2213. R2: TOC pointer
  2214. R3-R4: parameter passing and return values
  2215. R5-R10: parameter passing
  2216. R13: small data area pointer
  2217. R30: GOT pointer
  2218. R31: frame pointer
  2219. (U-Boot also uses R14 as internal GOT pointer.)
  2220. ==> U-Boot will use R29 to hold a pointer to the global data
  2221. Note: on PPC, we could use a static initializer (since the
  2222. address of the global data structure is known at compile time),
  2223. but it turned out that reserving a register results in somewhat
  2224. smaller code - although the code savings are not that big (on
  2225. average for all boards 752 bytes for the whole U-Boot image,
  2226. 624 text + 127 data).
  2227. On ARM, the following registers are used:
  2228. R0: function argument word/integer result
  2229. R1-R3: function argument word
  2230. R9: GOT pointer
  2231. R10: stack limit (used only if stack checking if enabled)
  2232. R11: argument (frame) pointer
  2233. R12: temporary workspace
  2234. R13: stack pointer
  2235. R14: link register
  2236. R15: program counter
  2237. ==> U-Boot will use R8 to hold a pointer to the global data
  2238. Memory Management:
  2239. ------------------
  2240. U-Boot runs in system state and uses physical addresses, i.e. the
  2241. MMU is not used either for address mapping nor for memory protection.
  2242. The available memory is mapped to fixed addresses using the memory
  2243. controller. In this process, a contiguous block is formed for each
  2244. memory type (Flash, SDRAM, SRAM), even when it consists of several
  2245. physical memory banks.
  2246. U-Boot is installed in the first 128 kB of the first Flash bank (on
  2247. TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
  2248. booting and sizing and initializing DRAM, the code relocates itself
  2249. to the upper end of DRAM. Immediately below the U-Boot code some
  2250. memory is reserved for use by malloc() [see CFG_MALLOC_LEN
  2251. configuration setting]. Below that, a structure with global Board
  2252. Info data is placed, followed by the stack (growing downward).
  2253. Additionally, some exception handler code is copied to the low 8 kB
  2254. of DRAM (0x00000000 ... 0x00001FFF).
  2255. So a typical memory configuration with 16 MB of DRAM could look like
  2256. this:
  2257. 0x0000 0000 Exception Vector code
  2258. :
  2259. 0x0000 1FFF
  2260. 0x0000 2000 Free for Application Use
  2261. :
  2262. :
  2263. :
  2264. :
  2265. 0x00FB FF20 Monitor Stack (Growing downward)
  2266. 0x00FB FFAC Board Info Data and permanent copy of global data
  2267. 0x00FC 0000 Malloc Arena
  2268. :
  2269. 0x00FD FFFF
  2270. 0x00FE 0000 RAM Copy of Monitor Code
  2271. ... eventually: LCD or video framebuffer
  2272. ... eventually: pRAM (Protected RAM - unchanged by reset)
  2273. 0x00FF FFFF [End of RAM]
  2274. System Initialization:
  2275. ----------------------
  2276. In the reset configuration, U-Boot starts at the reset entry point
  2277. (on most PowerPC systens at address 0x00000100). Because of the reset
  2278. configuration for CS0# this is a mirror of the onboard Flash memory.
  2279. To be able to re-map memory U-Boot then jumps to it's link address.
  2280. To be able to implement the initialization code in C, a (small!)
  2281. initial stack is set up in the internal Dual Ported RAM (in case CPUs
  2282. which provide such a feature like MPC8xx or MPC8260), or in a locked
  2283. part of the data cache. After that, U-Boot initializes the CPU core,
  2284. the caches and the SIU.
  2285. Next, all (potentially) available memory banks are mapped using a
  2286. preliminary mapping. For example, we put them on 512 MB boundaries
  2287. (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
  2288. on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
  2289. programmed for SDRAM access. Using the temporary configuration, a
  2290. simple memory test is run that determines the size of the SDRAM
  2291. banks.
  2292. When there is more than one SDRAM bank, and the banks are of
  2293. different size, the larger is mapped first. For equal size, the first
  2294. bank (CS2#) is mapped first. The first mapping is always for address
  2295. 0x00000000, with any additional banks following immediately to create
  2296. contiguous memory starting from 0.
  2297. Then, the monitor installs itself at the upper end of the SDRAM area
  2298. and allocates memory for use by malloc() and for the global Board
  2299. Info data; also, the exception vector code is copied to the low RAM
  2300. pages, and the final stack is set up.
  2301. Only after this relocation will you have a "normal" C environment;
  2302. until that you are restricted in several ways, mostly because you are
  2303. running from ROM, and because the code will have to be relocated to a
  2304. new address in RAM.
  2305. U-Boot Porting Guide:
  2306. ----------------------
  2307. [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
  2308. list, October 2002]
  2309. int main (int argc, char *argv[])
  2310. {
  2311. sighandler_t no_more_time;
  2312. signal (SIGALRM, no_more_time);
  2313. alarm (PROJECT_DEADLINE - toSec (3 * WEEK));
  2314. if (available_money > available_manpower) {
  2315. pay consultant to port U-Boot;
  2316. return 0;
  2317. }
  2318. Download latest U-Boot source;
  2319. Subscribe to u-boot-users mailing list;
  2320. if (clueless) {
  2321. email ("Hi, I am new to U-Boot, how do I get started?");
  2322. }
  2323. while (learning) {
  2324. Read the README file in the top level directory;
  2325. Read http://www.denx.de/re/DPLG.html
  2326. Read the source, Luke;
  2327. }
  2328. if (available_money > toLocalCurrency ($2500)) {
  2329. Buy a BDI2000;
  2330. } else {
  2331. Add a lot of aggravation and time;
  2332. }
  2333. Create your own board support subdirectory;
  2334. Create your own board config file;
  2335. while (!running) {
  2336. do {
  2337. Add / modify source code;
  2338. } until (compiles);
  2339. Debug;
  2340. if (clueless)
  2341. email ("Hi, I am having problems...");
  2342. }
  2343. Send patch file to Wolfgang;
  2344. return 0;
  2345. }
  2346. void no_more_time (int sig)
  2347. {
  2348. hire_a_guru();
  2349. }
  2350. Coding Standards:
  2351. -----------------
  2352. All contributions to U-Boot should conform to the Linux kernel
  2353. coding style; see the file "Documentation/CodingStyle" in your Linux
  2354. kernel source directory.
  2355. Please note that U-Boot is implemented in C (and to some small parts
  2356. in Assembler); no C++ is used, so please do not use C++ style
  2357. comments (//) in your code.
  2358. Submissions which do not conform to the standards may be returned
  2359. with a request to reformat the changes.
  2360. Submitting Patches:
  2361. -------------------
  2362. Since the number of patches for U-Boot is growing, we need to
  2363. establish some rules. Submissions which do not conform to these rules
  2364. may be rejected, even when they contain important and valuable stuff.
  2365. When you send a patch, please include the following information with
  2366. it:
  2367. * For bug fixes: a description of the bug and how your patch fixes
  2368. this bug. Please try to include a way of demonstrating that the
  2369. patch actually fixes something.
  2370. * For new features: a description of the feature and your
  2371. implementation.
  2372. * A CHANGELOG entry as plaintext (separate from the patch)
  2373. * For major contributions, your entry to the CREDITS file
  2374. * When you add support for a new board, don't forget to add this
  2375. board to the MAKEALL script, too.
  2376. * If your patch adds new configuration options, don't forget to
  2377. document these in the README file.
  2378. * The patch itself. If you are accessing the CVS repository use "cvs
  2379. update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your
  2380. version of diff does not support these options, then get the latest
  2381. version of GNU diff.
  2382. The current directory when running this command shall be the top
  2383. level directory of the U-Boot source tree, or it's parent directory
  2384. (i. e. please make sure that your patch includes sufficient
  2385. directory information for the affected files).
  2386. We accept patches as plain text, MIME attachments or as uuencoded
  2387. gzipped text.
  2388. * If one logical set of modifications affects or creates several
  2389. files, all these changes shall be submitted in a SINGLE patch file.
  2390. * Changesets that contain different, unrelated modifications shall be
  2391. submitted as SEPARATE patches, one patch per changeset.
  2392. Notes:
  2393. * Before sending the patch, run the MAKEALL script on your patched
  2394. source tree and make sure that no errors or warnings are reported
  2395. for any of the boards.
  2396. * Keep your modifications to the necessary minimum: A patch
  2397. containing several unrelated changes or arbitrary reformats will be
  2398. returned with a request to re-formatting / split it.
  2399. * If you modify existing code, make sure that your new code does not
  2400. add to the memory footprint of the code ;-) Small is beautiful!
  2401. When adding new features, these should compile conditionally only
  2402. (using #ifdef), and the resulting code with the new feature
  2403. disabled must not need more memory than the old code without your
  2404. modification.