README 170 KB

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  1. #
  2. # (C) Copyright 2000 - 2012
  3. # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  4. #
  5. # See file CREDITS for list of people who contributed to this
  6. # project.
  7. #
  8. # This program is free software; you can redistribute it and/or
  9. # modify it under the terms of the GNU General Public License as
  10. # published by the Free Software Foundation; either version 2 of
  11. # the License, or (at your option) any later version.
  12. #
  13. # This program is distributed in the hope that it will be useful,
  14. # but WITHOUT ANY WARRANTY; without even the implied warranty of
  15. # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16. # GNU General Public License for more details.
  17. #
  18. # You should have received a copy of the GNU General Public License
  19. # along with this program; if not, write to the Free Software
  20. # Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  21. # MA 02111-1307 USA
  22. #
  23. Summary:
  24. ========
  25. This directory contains the source code for U-Boot, a boot loader for
  26. Embedded boards based on PowerPC, ARM, MIPS and several other
  27. processors, which can be installed in a boot ROM and used to
  28. initialize and test the hardware or to download and run application
  29. code.
  30. The development of U-Boot is closely related to Linux: some parts of
  31. the source code originate in the Linux source tree, we have some
  32. header files in common, and special provision has been made to
  33. support booting of Linux images.
  34. Some attention has been paid to make this software easily
  35. configurable and extendable. For instance, all monitor commands are
  36. implemented with the same call interface, so that it's very easy to
  37. add new commands. Also, instead of permanently adding rarely used
  38. code (for instance hardware test utilities) to the monitor, you can
  39. load and run it dynamically.
  40. Status:
  41. =======
  42. In general, all boards for which a configuration option exists in the
  43. Makefile have been tested to some extent and can be considered
  44. "working". In fact, many of them are used in production systems.
  45. In case of problems see the CHANGELOG and CREDITS files to find out
  46. who contributed the specific port. The MAINTAINERS file lists board
  47. maintainers.
  48. Where to get help:
  49. ==================
  50. In case you have questions about, problems with or contributions for
  51. U-Boot you should send a message to the U-Boot mailing list at
  52. <u-boot@lists.denx.de>. There is also an archive of previous traffic
  53. on the mailing list - please search the archive before asking FAQ's.
  54. Please see http://lists.denx.de/pipermail/u-boot and
  55. http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
  56. Where to get source code:
  57. =========================
  58. The U-Boot source code is maintained in the git repository at
  59. git://www.denx.de/git/u-boot.git ; you can browse it online at
  60. http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
  61. The "snapshot" links on this page allow you to download tarballs of
  62. any version you might be interested in. Official releases are also
  63. available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
  64. directory.
  65. Pre-built (and tested) images are available from
  66. ftp://ftp.denx.de/pub/u-boot/images/
  67. Where we come from:
  68. ===================
  69. - start from 8xxrom sources
  70. - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
  71. - clean up code
  72. - make it easier to add custom boards
  73. - make it possible to add other [PowerPC] CPUs
  74. - extend functions, especially:
  75. * Provide extended interface to Linux boot loader
  76. * S-Record download
  77. * network boot
  78. * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
  79. - create ARMBoot project (http://sourceforge.net/projects/armboot)
  80. - add other CPU families (starting with ARM)
  81. - create U-Boot project (http://sourceforge.net/projects/u-boot)
  82. - current project page: see http://www.denx.de/wiki/U-Boot
  83. Names and Spelling:
  84. ===================
  85. The "official" name of this project is "Das U-Boot". The spelling
  86. "U-Boot" shall be used in all written text (documentation, comments
  87. in source files etc.). Example:
  88. This is the README file for the U-Boot project.
  89. File names etc. shall be based on the string "u-boot". Examples:
  90. include/asm-ppc/u-boot.h
  91. #include <asm/u-boot.h>
  92. Variable names, preprocessor constants etc. shall be either based on
  93. the string "u_boot" or on "U_BOOT". Example:
  94. U_BOOT_VERSION u_boot_logo
  95. IH_OS_U_BOOT u_boot_hush_start
  96. Versioning:
  97. ===========
  98. Starting with the release in October 2008, the names of the releases
  99. were changed from numerical release numbers without deeper meaning
  100. into a time stamp based numbering. Regular releases are identified by
  101. names consisting of the calendar year and month of the release date.
  102. Additional fields (if present) indicate release candidates or bug fix
  103. releases in "stable" maintenance trees.
  104. Examples:
  105. U-Boot v2009.11 - Release November 2009
  106. U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
  107. U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release
  108. Directory Hierarchy:
  109. ====================
  110. /arch Architecture specific files
  111. /arm Files generic to ARM architecture
  112. /cpu CPU specific files
  113. /arm720t Files specific to ARM 720 CPUs
  114. /arm920t Files specific to ARM 920 CPUs
  115. /at91 Files specific to Atmel AT91RM9200 CPU
  116. /imx Files specific to Freescale MC9328 i.MX CPUs
  117. /s3c24x0 Files specific to Samsung S3C24X0 CPUs
  118. /arm925t Files specific to ARM 925 CPUs
  119. /arm926ejs Files specific to ARM 926 CPUs
  120. /arm1136 Files specific to ARM 1136 CPUs
  121. /ixp Files specific to Intel XScale IXP CPUs
  122. /pxa Files specific to Intel XScale PXA CPUs
  123. /s3c44b0 Files specific to Samsung S3C44B0 CPUs
  124. /sa1100 Files specific to Intel StrongARM SA1100 CPUs
  125. /lib Architecture specific library files
  126. /avr32 Files generic to AVR32 architecture
  127. /cpu CPU specific files
  128. /lib Architecture specific library files
  129. /blackfin Files generic to Analog Devices Blackfin architecture
  130. /cpu CPU specific files
  131. /lib Architecture specific library files
  132. /x86 Files generic to x86 architecture
  133. /cpu CPU specific files
  134. /lib Architecture specific library files
  135. /m68k Files generic to m68k architecture
  136. /cpu CPU specific files
  137. /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
  138. /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
  139. /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
  140. /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
  141. /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
  142. /lib Architecture specific library files
  143. /microblaze Files generic to microblaze architecture
  144. /cpu CPU specific files
  145. /lib Architecture specific library files
  146. /mips Files generic to MIPS architecture
  147. /cpu CPU specific files
  148. /mips32 Files specific to MIPS32 CPUs
  149. /xburst Files specific to Ingenic XBurst CPUs
  150. /lib Architecture specific library files
  151. /nds32 Files generic to NDS32 architecture
  152. /cpu CPU specific files
  153. /n1213 Files specific to Andes Technology N1213 CPUs
  154. /lib Architecture specific library files
  155. /nios2 Files generic to Altera NIOS2 architecture
  156. /cpu CPU specific files
  157. /lib Architecture specific library files
  158. /powerpc Files generic to PowerPC architecture
  159. /cpu CPU specific files
  160. /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
  161. /mpc5xx Files specific to Freescale MPC5xx CPUs
  162. /mpc5xxx Files specific to Freescale MPC5xxx CPUs
  163. /mpc8xx Files specific to Freescale MPC8xx CPUs
  164. /mpc8220 Files specific to Freescale MPC8220 CPUs
  165. /mpc824x Files specific to Freescale MPC824x CPUs
  166. /mpc8260 Files specific to Freescale MPC8260 CPUs
  167. /mpc85xx Files specific to Freescale MPC85xx CPUs
  168. /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
  169. /lib Architecture specific library files
  170. /sh Files generic to SH architecture
  171. /cpu CPU specific files
  172. /sh2 Files specific to sh2 CPUs
  173. /sh3 Files specific to sh3 CPUs
  174. /sh4 Files specific to sh4 CPUs
  175. /lib Architecture specific library files
  176. /sparc Files generic to SPARC architecture
  177. /cpu CPU specific files
  178. /leon2 Files specific to Gaisler LEON2 SPARC CPU
  179. /leon3 Files specific to Gaisler LEON3 SPARC CPU
  180. /lib Architecture specific library files
  181. /api Machine/arch independent API for external apps
  182. /board Board dependent files
  183. /common Misc architecture independent functions
  184. /disk Code for disk drive partition handling
  185. /doc Documentation (don't expect too much)
  186. /drivers Commonly used device drivers
  187. /examples Example code for standalone applications, etc.
  188. /fs Filesystem code (cramfs, ext2, jffs2, etc.)
  189. /include Header Files
  190. /lib Files generic to all architectures
  191. /libfdt Library files to support flattened device trees
  192. /lzma Library files to support LZMA decompression
  193. /lzo Library files to support LZO decompression
  194. /net Networking code
  195. /post Power On Self Test
  196. /rtc Real Time Clock drivers
  197. /tools Tools to build S-Record or U-Boot images, etc.
  198. Software Configuration:
  199. =======================
  200. Configuration is usually done using C preprocessor defines; the
  201. rationale behind that is to avoid dead code whenever possible.
  202. There are two classes of configuration variables:
  203. * Configuration _OPTIONS_:
  204. These are selectable by the user and have names beginning with
  205. "CONFIG_".
  206. * Configuration _SETTINGS_:
  207. These depend on the hardware etc. and should not be meddled with if
  208. you don't know what you're doing; they have names beginning with
  209. "CONFIG_SYS_".
  210. Later we will add a configuration tool - probably similar to or even
  211. identical to what's used for the Linux kernel. Right now, we have to
  212. do the configuration by hand, which means creating some symbolic
  213. links and editing some configuration files. We use the TQM8xxL boards
  214. as an example here.
  215. Selection of Processor Architecture and Board Type:
  216. ---------------------------------------------------
  217. For all supported boards there are ready-to-use default
  218. configurations available; just type "make <board_name>_config".
  219. Example: For a TQM823L module type:
  220. cd u-boot
  221. make TQM823L_config
  222. For the Cogent platform, you need to specify the CPU type as well;
  223. e.g. "make cogent_mpc8xx_config". And also configure the cogent
  224. directory according to the instructions in cogent/README.
  225. Configuration Options:
  226. ----------------------
  227. Configuration depends on the combination of board and CPU type; all
  228. such information is kept in a configuration file
  229. "include/configs/<board_name>.h".
  230. Example: For a TQM823L module, all configuration settings are in
  231. "include/configs/TQM823L.h".
  232. Many of the options are named exactly as the corresponding Linux
  233. kernel configuration options. The intention is to make it easier to
  234. build a config tool - later.
  235. The following options need to be configured:
  236. - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
  237. - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
  238. - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
  239. Define exactly one, e.g. CONFIG_ATSTK1002
  240. - CPU Module Type: (if CONFIG_COGENT is defined)
  241. Define exactly one of
  242. CONFIG_CMA286_60_OLD
  243. --- FIXME --- not tested yet:
  244. CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
  245. CONFIG_CMA287_23, CONFIG_CMA287_50
  246. - Motherboard Type: (if CONFIG_COGENT is defined)
  247. Define exactly one of
  248. CONFIG_CMA101, CONFIG_CMA102
  249. - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
  250. Define one or more of
  251. CONFIG_CMA302
  252. - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
  253. Define one or more of
  254. CONFIG_LCD_HEARTBEAT - update a character position on
  255. the LCD display every second with
  256. a "rotator" |\-/|\-/
  257. - Board flavour: (if CONFIG_MPC8260ADS is defined)
  258. CONFIG_ADSTYPE
  259. Possible values are:
  260. CONFIG_SYS_8260ADS - original MPC8260ADS
  261. CONFIG_SYS_8266ADS - MPC8266ADS
  262. CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
  263. CONFIG_SYS_8272ADS - MPC8272ADS
  264. - Marvell Family Member
  265. CONFIG_SYS_MVFS - define it if you want to enable
  266. multiple fs option at one time
  267. for marvell soc family
  268. - MPC824X Family Member (if CONFIG_MPC824X is defined)
  269. Define exactly one of
  270. CONFIG_MPC8240, CONFIG_MPC8245
  271. - 8xx CPU Options: (if using an MPC8xx CPU)
  272. CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
  273. get_gclk_freq() cannot work
  274. e.g. if there is no 32KHz
  275. reference PIT/RTC clock
  276. CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
  277. or XTAL/EXTAL)
  278. - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
  279. CONFIG_SYS_8xx_CPUCLK_MIN
  280. CONFIG_SYS_8xx_CPUCLK_MAX
  281. CONFIG_8xx_CPUCLK_DEFAULT
  282. See doc/README.MPC866
  283. CONFIG_SYS_MEASURE_CPUCLK
  284. Define this to measure the actual CPU clock instead
  285. of relying on the correctness of the configured
  286. values. Mostly useful for board bringup to make sure
  287. the PLL is locked at the intended frequency. Note
  288. that this requires a (stable) reference clock (32 kHz
  289. RTC clock or CONFIG_SYS_8XX_XIN)
  290. CONFIG_SYS_DELAYED_ICACHE
  291. Define this option if you want to enable the
  292. ICache only when Code runs from RAM.
  293. - 85xx CPU Options:
  294. CONFIG_SYS_FSL_TBCLK_DIV
  295. Defines the core time base clock divider ratio compared to the
  296. system clock. On most PQ3 devices this is 8, on newer QorIQ
  297. devices it can be 16 or 32. The ratio varies from SoC to Soc.
  298. CONFIG_SYS_FSL_PCIE_COMPAT
  299. Defines the string to utilize when trying to match PCIe device
  300. tree nodes for the given platform.
  301. - Intel Monahans options:
  302. CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
  303. Defines the Monahans run mode to oscillator
  304. ratio. Valid values are 8, 16, 24, 31. The core
  305. frequency is this value multiplied by 13 MHz.
  306. CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
  307. Defines the Monahans turbo mode to oscillator
  308. ratio. Valid values are 1 (default if undefined) and
  309. 2. The core frequency as calculated above is multiplied
  310. by this value.
  311. - MIPS CPU options:
  312. CONFIG_SYS_INIT_SP_OFFSET
  313. Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
  314. pointer. This is needed for the temporary stack before
  315. relocation.
  316. CONFIG_SYS_MIPS_CACHE_MODE
  317. Cache operation mode for the MIPS CPU.
  318. See also arch/mips/include/asm/mipsregs.h.
  319. Possible values are:
  320. CONF_CM_CACHABLE_NO_WA
  321. CONF_CM_CACHABLE_WA
  322. CONF_CM_UNCACHED
  323. CONF_CM_CACHABLE_NONCOHERENT
  324. CONF_CM_CACHABLE_CE
  325. CONF_CM_CACHABLE_COW
  326. CONF_CM_CACHABLE_CUW
  327. CONF_CM_CACHABLE_ACCELERATED
  328. CONFIG_SYS_XWAY_EBU_BOOTCFG
  329. Special option for Lantiq XWAY SoCs for booting from NOR flash.
  330. See also arch/mips/cpu/mips32/start.S.
  331. CONFIG_XWAY_SWAP_BYTES
  332. Enable compilation of tools/xway-swap-bytes needed for Lantiq
  333. XWAY SoCs for booting from NOR flash. The U-Boot image needs to
  334. be swapped if a flash programmer is used.
  335. - ARM options:
  336. CONFIG_SYS_EXCEPTION_VECTORS_HIGH
  337. Select high exception vectors of the ARM core, e.g., do not
  338. clear the V bit of the c1 register of CP15.
  339. - Linux Kernel Interface:
  340. CONFIG_CLOCKS_IN_MHZ
  341. U-Boot stores all clock information in Hz
  342. internally. For binary compatibility with older Linux
  343. kernels (which expect the clocks passed in the
  344. bd_info data to be in MHz) the environment variable
  345. "clocks_in_mhz" can be defined so that U-Boot
  346. converts clock data to MHZ before passing it to the
  347. Linux kernel.
  348. When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
  349. "clocks_in_mhz=1" is automatically included in the
  350. default environment.
  351. CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
  352. When transferring memsize parameter to linux, some versions
  353. expect it to be in bytes, others in MB.
  354. Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
  355. CONFIG_OF_LIBFDT
  356. New kernel versions are expecting firmware settings to be
  357. passed using flattened device trees (based on open firmware
  358. concepts).
  359. CONFIG_OF_LIBFDT
  360. * New libfdt-based support
  361. * Adds the "fdt" command
  362. * The bootm command automatically updates the fdt
  363. OF_CPU - The proper name of the cpus node (only required for
  364. MPC512X and MPC5xxx based boards).
  365. OF_SOC - The proper name of the soc node (only required for
  366. MPC512X and MPC5xxx based boards).
  367. OF_TBCLK - The timebase frequency.
  368. OF_STDOUT_PATH - The path to the console device
  369. boards with QUICC Engines require OF_QE to set UCC MAC
  370. addresses
  371. CONFIG_OF_BOARD_SETUP
  372. Board code has addition modification that it wants to make
  373. to the flat device tree before handing it off to the kernel
  374. CONFIG_OF_BOOT_CPU
  375. This define fills in the correct boot CPU in the boot
  376. param header, the default value is zero if undefined.
  377. CONFIG_OF_IDE_FIXUP
  378. U-Boot can detect if an IDE device is present or not.
  379. If not, and this new config option is activated, U-Boot
  380. removes the ATA node from the DTS before booting Linux,
  381. so the Linux IDE driver does not probe the device and
  382. crash. This is needed for buggy hardware (uc101) where
  383. no pull down resistor is connected to the signal IDE5V_DD7.
  384. CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
  385. This setting is mandatory for all boards that have only one
  386. machine type and must be used to specify the machine type
  387. number as it appears in the ARM machine registry
  388. (see http://www.arm.linux.org.uk/developer/machines/).
  389. Only boards that have multiple machine types supported
  390. in a single configuration file and the machine type is
  391. runtime discoverable, do not have to use this setting.
  392. - vxWorks boot parameters:
  393. bootvx constructs a valid bootline using the following
  394. environments variables: bootfile, ipaddr, serverip, hostname.
  395. It loads the vxWorks image pointed bootfile.
  396. CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
  397. CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
  398. CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
  399. CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
  400. CONFIG_SYS_VXWORKS_ADD_PARAMS
  401. Add it at the end of the bootline. E.g "u=username pw=secret"
  402. Note: If a "bootargs" environment is defined, it will overwride
  403. the defaults discussed just above.
  404. - Cache Configuration:
  405. CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
  406. CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
  407. CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
  408. - Cache Configuration for ARM:
  409. CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
  410. controller
  411. CONFIG_SYS_PL310_BASE - Physical base address of PL310
  412. controller register space
  413. - Serial Ports:
  414. CONFIG_PL010_SERIAL
  415. Define this if you want support for Amba PrimeCell PL010 UARTs.
  416. CONFIG_PL011_SERIAL
  417. Define this if you want support for Amba PrimeCell PL011 UARTs.
  418. CONFIG_PL011_CLOCK
  419. If you have Amba PrimeCell PL011 UARTs, set this variable to
  420. the clock speed of the UARTs.
  421. CONFIG_PL01x_PORTS
  422. If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
  423. define this to a list of base addresses for each (supported)
  424. port. See e.g. include/configs/versatile.h
  425. CONFIG_PL011_SERIAL_RLCR
  426. Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
  427. have separate receive and transmit line control registers. Set
  428. this variable to initialize the extra register.
  429. CONFIG_PL011_SERIAL_FLUSH_ON_INIT
  430. On some platforms (e.g. U8500) U-Boot is loaded by a second stage
  431. boot loader that has already initialized the UART. Define this
  432. variable to flush the UART at init time.
  433. - Console Interface:
  434. Depending on board, define exactly one serial port
  435. (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
  436. CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
  437. console by defining CONFIG_8xx_CONS_NONE
  438. Note: if CONFIG_8xx_CONS_NONE is defined, the serial
  439. port routines must be defined elsewhere
  440. (i.e. serial_init(), serial_getc(), ...)
  441. CONFIG_CFB_CONSOLE
  442. Enables console device for a color framebuffer. Needs following
  443. defines (cf. smiLynxEM, i8042)
  444. VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
  445. (default big endian)
  446. VIDEO_HW_RECTFILL graphic chip supports
  447. rectangle fill
  448. (cf. smiLynxEM)
  449. VIDEO_HW_BITBLT graphic chip supports
  450. bit-blit (cf. smiLynxEM)
  451. VIDEO_VISIBLE_COLS visible pixel columns
  452. (cols=pitch)
  453. VIDEO_VISIBLE_ROWS visible pixel rows
  454. VIDEO_PIXEL_SIZE bytes per pixel
  455. VIDEO_DATA_FORMAT graphic data format
  456. (0-5, cf. cfb_console.c)
  457. VIDEO_FB_ADRS framebuffer address
  458. VIDEO_KBD_INIT_FCT keyboard int fct
  459. (i.e. i8042_kbd_init())
  460. VIDEO_TSTC_FCT test char fct
  461. (i.e. i8042_tstc)
  462. VIDEO_GETC_FCT get char fct
  463. (i.e. i8042_getc)
  464. CONFIG_CONSOLE_CURSOR cursor drawing on/off
  465. (requires blink timer
  466. cf. i8042.c)
  467. CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
  468. CONFIG_CONSOLE_TIME display time/date info in
  469. upper right corner
  470. (requires CONFIG_CMD_DATE)
  471. CONFIG_VIDEO_LOGO display Linux logo in
  472. upper left corner
  473. CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
  474. linux_logo.h for logo.
  475. Requires CONFIG_VIDEO_LOGO
  476. CONFIG_CONSOLE_EXTRA_INFO
  477. additional board info beside
  478. the logo
  479. When CONFIG_CFB_CONSOLE is defined, video console is
  480. default i/o. Serial console can be forced with
  481. environment 'console=serial'.
  482. When CONFIG_SILENT_CONSOLE is defined, all console
  483. messages (by U-Boot and Linux!) can be silenced with
  484. the "silent" environment variable. See
  485. doc/README.silent for more information.
  486. - Console Baudrate:
  487. CONFIG_BAUDRATE - in bps
  488. Select one of the baudrates listed in
  489. CONFIG_SYS_BAUDRATE_TABLE, see below.
  490. CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
  491. - Console Rx buffer length
  492. With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
  493. the maximum receive buffer length for the SMC.
  494. This option is actual only for 82xx and 8xx possible.
  495. If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
  496. must be defined, to setup the maximum idle timeout for
  497. the SMC.
  498. - Pre-Console Buffer:
  499. Prior to the console being initialised (i.e. serial UART
  500. initialised etc) all console output is silently discarded.
  501. Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to
  502. buffer any console messages prior to the console being
  503. initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ
  504. bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is
  505. a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ
  506. bytes are output before the console is initialised, the
  507. earlier bytes are discarded.
  508. 'Sane' compilers will generate smaller code if
  509. CONFIG_PRE_CON_BUF_SZ is a power of 2
  510. - Safe printf() functions
  511. Define CONFIG_SYS_VSNPRINTF to compile in safe versions of
  512. the printf() functions. These are defined in
  513. include/vsprintf.h and include snprintf(), vsnprintf() and
  514. so on. Code size increase is approximately 300-500 bytes.
  515. If this option is not given then these functions will
  516. silently discard their buffer size argument - this means
  517. you are not getting any overflow checking in this case.
  518. - Boot Delay: CONFIG_BOOTDELAY - in seconds
  519. Delay before automatically booting the default image;
  520. set to -1 to disable autoboot.
  521. See doc/README.autoboot for these options that
  522. work with CONFIG_BOOTDELAY. None are required.
  523. CONFIG_BOOT_RETRY_TIME
  524. CONFIG_BOOT_RETRY_MIN
  525. CONFIG_AUTOBOOT_KEYED
  526. CONFIG_AUTOBOOT_PROMPT
  527. CONFIG_AUTOBOOT_DELAY_STR
  528. CONFIG_AUTOBOOT_STOP_STR
  529. CONFIG_AUTOBOOT_DELAY_STR2
  530. CONFIG_AUTOBOOT_STOP_STR2
  531. CONFIG_ZERO_BOOTDELAY_CHECK
  532. CONFIG_RESET_TO_RETRY
  533. - Autoboot Command:
  534. CONFIG_BOOTCOMMAND
  535. Only needed when CONFIG_BOOTDELAY is enabled;
  536. define a command string that is automatically executed
  537. when no character is read on the console interface
  538. within "Boot Delay" after reset.
  539. CONFIG_BOOTARGS
  540. This can be used to pass arguments to the bootm
  541. command. The value of CONFIG_BOOTARGS goes into the
  542. environment value "bootargs".
  543. CONFIG_RAMBOOT and CONFIG_NFSBOOT
  544. The value of these goes into the environment as
  545. "ramboot" and "nfsboot" respectively, and can be used
  546. as a convenience, when switching between booting from
  547. RAM and NFS.
  548. - Pre-Boot Commands:
  549. CONFIG_PREBOOT
  550. When this option is #defined, the existence of the
  551. environment variable "preboot" will be checked
  552. immediately before starting the CONFIG_BOOTDELAY
  553. countdown and/or running the auto-boot command resp.
  554. entering interactive mode.
  555. This feature is especially useful when "preboot" is
  556. automatically generated or modified. For an example
  557. see the LWMON board specific code: here "preboot" is
  558. modified when the user holds down a certain
  559. combination of keys on the (special) keyboard when
  560. booting the systems
  561. - Serial Download Echo Mode:
  562. CONFIG_LOADS_ECHO
  563. If defined to 1, all characters received during a
  564. serial download (using the "loads" command) are
  565. echoed back. This might be needed by some terminal
  566. emulations (like "cu"), but may as well just take
  567. time on others. This setting #define's the initial
  568. value of the "loads_echo" environment variable.
  569. - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
  570. CONFIG_KGDB_BAUDRATE
  571. Select one of the baudrates listed in
  572. CONFIG_SYS_BAUDRATE_TABLE, see below.
  573. - Monitor Functions:
  574. Monitor commands can be included or excluded
  575. from the build by using the #include files
  576. "config_cmd_all.h" and #undef'ing unwanted
  577. commands, or using "config_cmd_default.h"
  578. and augmenting with additional #define's
  579. for wanted commands.
  580. The default command configuration includes all commands
  581. except those marked below with a "*".
  582. CONFIG_CMD_ASKENV * ask for env variable
  583. CONFIG_CMD_BDI bdinfo
  584. CONFIG_CMD_BEDBUG * Include BedBug Debugger
  585. CONFIG_CMD_BMP * BMP support
  586. CONFIG_CMD_BSP * Board specific commands
  587. CONFIG_CMD_BOOTD bootd
  588. CONFIG_CMD_CACHE * icache, dcache
  589. CONFIG_CMD_CONSOLE coninfo
  590. CONFIG_CMD_CRC32 * crc32
  591. CONFIG_CMD_DATE * support for RTC, date/time...
  592. CONFIG_CMD_DHCP * DHCP support
  593. CONFIG_CMD_DIAG * Diagnostics
  594. CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
  595. CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
  596. CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
  597. CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
  598. CONFIG_CMD_DTT * Digital Therm and Thermostat
  599. CONFIG_CMD_ECHO echo arguments
  600. CONFIG_CMD_EDITENV edit env variable
  601. CONFIG_CMD_EEPROM * EEPROM read/write support
  602. CONFIG_CMD_ELF * bootelf, bootvx
  603. CONFIG_CMD_EXPORTENV * export the environment
  604. CONFIG_CMD_SAVEENV saveenv
  605. CONFIG_CMD_FDC * Floppy Disk Support
  606. CONFIG_CMD_FAT * FAT partition support
  607. CONFIG_CMD_FDOS * Dos diskette Support
  608. CONFIG_CMD_FLASH flinfo, erase, protect
  609. CONFIG_CMD_FPGA FPGA device initialization support
  610. CONFIG_CMD_GO * the 'go' command (exec code)
  611. CONFIG_CMD_GREPENV * search environment
  612. CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
  613. CONFIG_CMD_I2C * I2C serial bus support
  614. CONFIG_CMD_IDE * IDE harddisk support
  615. CONFIG_CMD_IMI iminfo
  616. CONFIG_CMD_IMLS List all found images
  617. CONFIG_CMD_IMMAP * IMMR dump support
  618. CONFIG_CMD_IMPORTENV * import an environment
  619. CONFIG_CMD_IRQ * irqinfo
  620. CONFIG_CMD_ITEST Integer/string test of 2 values
  621. CONFIG_CMD_JFFS2 * JFFS2 Support
  622. CONFIG_CMD_KGDB * kgdb
  623. CONFIG_CMD_LDRINFO ldrinfo (display Blackfin loader)
  624. CONFIG_CMD_LOADB loadb
  625. CONFIG_CMD_LOADS loads
  626. CONFIG_CMD_MD5SUM print md5 message digest
  627. (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
  628. CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
  629. loop, loopw, mtest
  630. CONFIG_CMD_MISC Misc functions like sleep etc
  631. CONFIG_CMD_MMC * MMC memory mapped support
  632. CONFIG_CMD_MII * MII utility commands
  633. CONFIG_CMD_MTDPARTS * MTD partition support
  634. CONFIG_CMD_NAND * NAND support
  635. CONFIG_CMD_NET bootp, tftpboot, rarpboot
  636. CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
  637. CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
  638. CONFIG_CMD_PCI * pciinfo
  639. CONFIG_CMD_PCMCIA * PCMCIA support
  640. CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
  641. host
  642. CONFIG_CMD_PORTIO * Port I/O
  643. CONFIG_CMD_REGINFO * Register dump
  644. CONFIG_CMD_RUN run command in env variable
  645. CONFIG_CMD_SAVES * save S record dump
  646. CONFIG_CMD_SCSI * SCSI Support
  647. CONFIG_CMD_SDRAM * print SDRAM configuration information
  648. (requires CONFIG_CMD_I2C)
  649. CONFIG_CMD_SETGETDCR Support for DCR Register access
  650. (4xx only)
  651. CONFIG_CMD_SF * Read/write/erase SPI NOR flash
  652. CONFIG_CMD_SHA1SUM print sha1 memory digest
  653. (requires CONFIG_CMD_MEMORY)
  654. CONFIG_CMD_SOURCE "source" command Support
  655. CONFIG_CMD_SPI * SPI serial bus support
  656. CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
  657. CONFIG_CMD_TFTPPUT * TFTP put command (upload)
  658. CONFIG_CMD_TIME * run command and report execution time
  659. CONFIG_CMD_USB * USB support
  660. CONFIG_CMD_CDP * Cisco Discover Protocol support
  661. CONFIG_CMD_FSL * Microblaze FSL support
  662. EXAMPLE: If you want all functions except of network
  663. support you can write:
  664. #include "config_cmd_all.h"
  665. #undef CONFIG_CMD_NET
  666. Other Commands:
  667. fdt (flattened device tree) command: CONFIG_OF_LIBFDT
  668. Note: Don't enable the "icache" and "dcache" commands
  669. (configuration option CONFIG_CMD_CACHE) unless you know
  670. what you (and your U-Boot users) are doing. Data
  671. cache cannot be enabled on systems like the 8xx or
  672. 8260 (where accesses to the IMMR region must be
  673. uncached), and it cannot be disabled on all other
  674. systems where we (mis-) use the data cache to hold an
  675. initial stack and some data.
  676. XXX - this list needs to get updated!
  677. - Device tree:
  678. CONFIG_OF_CONTROL
  679. If this variable is defined, U-Boot will use a device tree
  680. to configure its devices, instead of relying on statically
  681. compiled #defines in the board file. This option is
  682. experimental and only available on a few boards. The device
  683. tree is available in the global data as gd->fdt_blob.
  684. U-Boot needs to get its device tree from somewhere. This can
  685. be done using one of the two options below:
  686. CONFIG_OF_EMBED
  687. If this variable is defined, U-Boot will embed a device tree
  688. binary in its image. This device tree file should be in the
  689. board directory and called <soc>-<board>.dts. The binary file
  690. is then picked up in board_init_f() and made available through
  691. the global data structure as gd->blob.
  692. CONFIG_OF_SEPARATE
  693. If this variable is defined, U-Boot will build a device tree
  694. binary. It will be called u-boot.dtb. Architecture-specific
  695. code will locate it at run-time. Generally this works by:
  696. cat u-boot.bin u-boot.dtb >image.bin
  697. and in fact, U-Boot does this for you, creating a file called
  698. u-boot-dtb.bin which is useful in the common case. You can
  699. still use the individual files if you need something more
  700. exotic.
  701. - Watchdog:
  702. CONFIG_WATCHDOG
  703. If this variable is defined, it enables watchdog
  704. support for the SoC. There must be support in the SoC
  705. specific code for a watchdog. For the 8xx and 8260
  706. CPUs, the SIU Watchdog feature is enabled in the SYPCR
  707. register. When supported for a specific SoC is
  708. available, then no further board specific code should
  709. be needed to use it.
  710. CONFIG_HW_WATCHDOG
  711. When using a watchdog circuitry external to the used
  712. SoC, then define this variable and provide board
  713. specific code for the "hw_watchdog_reset" function.
  714. - U-Boot Version:
  715. CONFIG_VERSION_VARIABLE
  716. If this variable is defined, an environment variable
  717. named "ver" is created by U-Boot showing the U-Boot
  718. version as printed by the "version" command.
  719. This variable is readonly.
  720. - Real-Time Clock:
  721. When CONFIG_CMD_DATE is selected, the type of the RTC
  722. has to be selected, too. Define exactly one of the
  723. following options:
  724. CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
  725. CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
  726. CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
  727. CONFIG_RTC_MC146818 - use MC146818 RTC
  728. CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
  729. CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
  730. CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
  731. CONFIG_RTC_DS164x - use Dallas DS164x RTC
  732. CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
  733. CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
  734. CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
  735. CONFIG_SYS_RV3029_TCR - enable trickle charger on
  736. RV3029 RTC.
  737. Note that if the RTC uses I2C, then the I2C interface
  738. must also be configured. See I2C Support, below.
  739. - GPIO Support:
  740. CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
  741. CONFIG_PCA953X_INFO - enable pca953x info command
  742. The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
  743. chip-ngpio pairs that tell the PCA953X driver the number of
  744. pins supported by a particular chip.
  745. Note that if the GPIO device uses I2C, then the I2C interface
  746. must also be configured. See I2C Support, below.
  747. - Timestamp Support:
  748. When CONFIG_TIMESTAMP is selected, the timestamp
  749. (date and time) of an image is printed by image
  750. commands like bootm or iminfo. This option is
  751. automatically enabled when you select CONFIG_CMD_DATE .
  752. - Partition Support:
  753. CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
  754. and/or CONFIG_ISO_PARTITION and/or CONFIG_EFI_PARTITION
  755. If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
  756. CONFIG_CMD_SCSI) you must configure support for at
  757. least one partition type as well.
  758. - IDE Reset method:
  759. CONFIG_IDE_RESET_ROUTINE - this is defined in several
  760. board configurations files but used nowhere!
  761. CONFIG_IDE_RESET - is this is defined, IDE Reset will
  762. be performed by calling the function
  763. ide_set_reset(int reset)
  764. which has to be defined in a board specific file
  765. - ATAPI Support:
  766. CONFIG_ATAPI
  767. Set this to enable ATAPI support.
  768. - LBA48 Support
  769. CONFIG_LBA48
  770. Set this to enable support for disks larger than 137GB
  771. Also look at CONFIG_SYS_64BIT_LBA.
  772. Whithout these , LBA48 support uses 32bit variables and will 'only'
  773. support disks up to 2.1TB.
  774. CONFIG_SYS_64BIT_LBA:
  775. When enabled, makes the IDE subsystem use 64bit sector addresses.
  776. Default is 32bit.
  777. - SCSI Support:
  778. At the moment only there is only support for the
  779. SYM53C8XX SCSI controller; define
  780. CONFIG_SCSI_SYM53C8XX to enable it.
  781. CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
  782. CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
  783. CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
  784. maximum numbers of LUNs, SCSI ID's and target
  785. devices.
  786. CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
  787. - NETWORK Support (PCI):
  788. CONFIG_E1000
  789. Support for Intel 8254x/8257x gigabit chips.
  790. CONFIG_E1000_SPI
  791. Utility code for direct access to the SPI bus on Intel 8257x.
  792. This does not do anything useful unless you set at least one
  793. of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
  794. CONFIG_E1000_SPI_GENERIC
  795. Allow generic access to the SPI bus on the Intel 8257x, for
  796. example with the "sspi" command.
  797. CONFIG_CMD_E1000
  798. Management command for E1000 devices. When used on devices
  799. with SPI support you can reprogram the EEPROM from U-Boot.
  800. CONFIG_E1000_FALLBACK_MAC
  801. default MAC for empty EEPROM after production.
  802. CONFIG_EEPRO100
  803. Support for Intel 82557/82559/82559ER chips.
  804. Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
  805. write routine for first time initialisation.
  806. CONFIG_TULIP
  807. Support for Digital 2114x chips.
  808. Optional CONFIG_TULIP_SELECT_MEDIA for board specific
  809. modem chip initialisation (KS8761/QS6611).
  810. CONFIG_NATSEMI
  811. Support for National dp83815 chips.
  812. CONFIG_NS8382X
  813. Support for National dp8382[01] gigabit chips.
  814. - NETWORK Support (other):
  815. CONFIG_DRIVER_AT91EMAC
  816. Support for AT91RM9200 EMAC.
  817. CONFIG_RMII
  818. Define this to use reduced MII inteface
  819. CONFIG_DRIVER_AT91EMAC_QUIET
  820. If this defined, the driver is quiet.
  821. The driver doen't show link status messages.
  822. CONFIG_CALXEDA_XGMAC
  823. Support for the Calxeda XGMAC device
  824. CONFIG_DRIVER_LAN91C96
  825. Support for SMSC's LAN91C96 chips.
  826. CONFIG_LAN91C96_BASE
  827. Define this to hold the physical address
  828. of the LAN91C96's I/O space
  829. CONFIG_LAN91C96_USE_32_BIT
  830. Define this to enable 32 bit addressing
  831. CONFIG_DRIVER_SMC91111
  832. Support for SMSC's LAN91C111 chip
  833. CONFIG_SMC91111_BASE
  834. Define this to hold the physical address
  835. of the device (I/O space)
  836. CONFIG_SMC_USE_32_BIT
  837. Define this if data bus is 32 bits
  838. CONFIG_SMC_USE_IOFUNCS
  839. Define this to use i/o functions instead of macros
  840. (some hardware wont work with macros)
  841. CONFIG_DRIVER_TI_EMAC
  842. Support for davinci emac
  843. CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
  844. Define this if you have more then 3 PHYs.
  845. CONFIG_FTGMAC100
  846. Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
  847. CONFIG_FTGMAC100_EGIGA
  848. Define this to use GE link update with gigabit PHY.
  849. Define this if FTGMAC100 is connected to gigabit PHY.
  850. If your system has 10/100 PHY only, it might not occur
  851. wrong behavior. Because PHY usually return timeout or
  852. useless data when polling gigabit status and gigabit
  853. control registers. This behavior won't affect the
  854. correctnessof 10/100 link speed update.
  855. CONFIG_SMC911X
  856. Support for SMSC's LAN911x and LAN921x chips
  857. CONFIG_SMC911X_BASE
  858. Define this to hold the physical address
  859. of the device (I/O space)
  860. CONFIG_SMC911X_32_BIT
  861. Define this if data bus is 32 bits
  862. CONFIG_SMC911X_16_BIT
  863. Define this if data bus is 16 bits. If your processor
  864. automatically converts one 32 bit word to two 16 bit
  865. words you may also try CONFIG_SMC911X_32_BIT.
  866. CONFIG_SH_ETHER
  867. Support for Renesas on-chip Ethernet controller
  868. CONFIG_SH_ETHER_USE_PORT
  869. Define the number of ports to be used
  870. CONFIG_SH_ETHER_PHY_ADDR
  871. Define the ETH PHY's address
  872. CONFIG_SH_ETHER_CACHE_WRITEBACK
  873. If this option is set, the driver enables cache flush.
  874. - TPM Support:
  875. CONFIG_GENERIC_LPC_TPM
  876. Support for generic parallel port TPM devices. Only one device
  877. per system is supported at this time.
  878. CONFIG_TPM_TIS_BASE_ADDRESS
  879. Base address where the generic TPM device is mapped
  880. to. Contemporary x86 systems usually map it at
  881. 0xfed40000.
  882. - USB Support:
  883. At the moment only the UHCI host controller is
  884. supported (PIP405, MIP405, MPC5200); define
  885. CONFIG_USB_UHCI to enable it.
  886. define CONFIG_USB_KEYBOARD to enable the USB Keyboard
  887. and define CONFIG_USB_STORAGE to enable the USB
  888. storage devices.
  889. Note:
  890. Supported are USB Keyboards and USB Floppy drives
  891. (TEAC FD-05PUB).
  892. MPC5200 USB requires additional defines:
  893. CONFIG_USB_CLOCK
  894. for 528 MHz Clock: 0x0001bbbb
  895. CONFIG_PSC3_USB
  896. for USB on PSC3
  897. CONFIG_USB_CONFIG
  898. for differential drivers: 0x00001000
  899. for single ended drivers: 0x00005000
  900. for differential drivers on PSC3: 0x00000100
  901. for single ended drivers on PSC3: 0x00004100
  902. CONFIG_SYS_USB_EVENT_POLL
  903. May be defined to allow interrupt polling
  904. instead of using asynchronous interrupts
  905. CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
  906. txfilltuning field in the EHCI controller on reset.
  907. - USB Device:
  908. Define the below if you wish to use the USB console.
  909. Once firmware is rebuilt from a serial console issue the
  910. command "setenv stdin usbtty; setenv stdout usbtty" and
  911. attach your USB cable. The Unix command "dmesg" should print
  912. it has found a new device. The environment variable usbtty
  913. can be set to gserial or cdc_acm to enable your device to
  914. appear to a USB host as a Linux gserial device or a
  915. Common Device Class Abstract Control Model serial device.
  916. If you select usbtty = gserial you should be able to enumerate
  917. a Linux host by
  918. # modprobe usbserial vendor=0xVendorID product=0xProductID
  919. else if using cdc_acm, simply setting the environment
  920. variable usbtty to be cdc_acm should suffice. The following
  921. might be defined in YourBoardName.h
  922. CONFIG_USB_DEVICE
  923. Define this to build a UDC device
  924. CONFIG_USB_TTY
  925. Define this to have a tty type of device available to
  926. talk to the UDC device
  927. CONFIG_SYS_CONSOLE_IS_IN_ENV
  928. Define this if you want stdin, stdout &/or stderr to
  929. be set to usbtty.
  930. mpc8xx:
  931. CONFIG_SYS_USB_EXTC_CLK 0xBLAH
  932. Derive USB clock from external clock "blah"
  933. - CONFIG_SYS_USB_EXTC_CLK 0x02
  934. CONFIG_SYS_USB_BRG_CLK 0xBLAH
  935. Derive USB clock from brgclk
  936. - CONFIG_SYS_USB_BRG_CLK 0x04
  937. If you have a USB-IF assigned VendorID then you may wish to
  938. define your own vendor specific values either in BoardName.h
  939. or directly in usbd_vendor_info.h. If you don't define
  940. CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
  941. CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
  942. should pretend to be a Linux device to it's target host.
  943. CONFIG_USBD_MANUFACTURER
  944. Define this string as the name of your company for
  945. - CONFIG_USBD_MANUFACTURER "my company"
  946. CONFIG_USBD_PRODUCT_NAME
  947. Define this string as the name of your product
  948. - CONFIG_USBD_PRODUCT_NAME "acme usb device"
  949. CONFIG_USBD_VENDORID
  950. Define this as your assigned Vendor ID from the USB
  951. Implementors Forum. This *must* be a genuine Vendor ID
  952. to avoid polluting the USB namespace.
  953. - CONFIG_USBD_VENDORID 0xFFFF
  954. CONFIG_USBD_PRODUCTID
  955. Define this as the unique Product ID
  956. for your device
  957. - CONFIG_USBD_PRODUCTID 0xFFFF
  958. - ULPI Layer Support:
  959. The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
  960. the generic ULPI layer. The generic layer accesses the ULPI PHY
  961. via the platform viewport, so you need both the genric layer and
  962. the viewport enabled. Currently only Chipidea/ARC based
  963. viewport is supported.
  964. To enable the ULPI layer support, define CONFIG_USB_ULPI and
  965. CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
  966. - MMC Support:
  967. The MMC controller on the Intel PXA is supported. To
  968. enable this define CONFIG_MMC. The MMC can be
  969. accessed from the boot prompt by mapping the device
  970. to physical memory similar to flash. Command line is
  971. enabled with CONFIG_CMD_MMC. The MMC driver also works with
  972. the FAT fs. This is enabled with CONFIG_CMD_FAT.
  973. CONFIG_SH_MMCIF
  974. Support for Renesas on-chip MMCIF controller
  975. CONFIG_SH_MMCIF_ADDR
  976. Define the base address of MMCIF registers
  977. CONFIG_SH_MMCIF_CLK
  978. Define the clock frequency for MMCIF
  979. - Journaling Flash filesystem support:
  980. CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
  981. CONFIG_JFFS2_NAND_DEV
  982. Define these for a default partition on a NAND device
  983. CONFIG_SYS_JFFS2_FIRST_SECTOR,
  984. CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
  985. Define these for a default partition on a NOR device
  986. CONFIG_SYS_JFFS_CUSTOM_PART
  987. Define this to create an own partition. You have to provide a
  988. function struct part_info* jffs2_part_info(int part_num)
  989. If you define only one JFFS2 partition you may also want to
  990. #define CONFIG_SYS_JFFS_SINGLE_PART 1
  991. to disable the command chpart. This is the default when you
  992. have not defined a custom partition
  993. - FAT(File Allocation Table) filesystem write function support:
  994. CONFIG_FAT_WRITE
  995. Define this to enable support for saving memory data as a
  996. file in FAT formatted partition.
  997. This will also enable the command "fatwrite" enabling the
  998. user to write files to FAT.
  999. - Keyboard Support:
  1000. CONFIG_ISA_KEYBOARD
  1001. Define this to enable standard (PC-Style) keyboard
  1002. support
  1003. CONFIG_I8042_KBD
  1004. Standard PC keyboard driver with US (is default) and
  1005. GERMAN key layout (switch via environment 'keymap=de') support.
  1006. Export function i8042_kbd_init, i8042_tstc and i8042_getc
  1007. for cfb_console. Supports cursor blinking.
  1008. - Video support:
  1009. CONFIG_VIDEO
  1010. Define this to enable video support (for output to
  1011. video).
  1012. CONFIG_VIDEO_CT69000
  1013. Enable Chips & Technologies 69000 Video chip
  1014. CONFIG_VIDEO_SMI_LYNXEM
  1015. Enable Silicon Motion SMI 712/710/810 Video chip. The
  1016. video output is selected via environment 'videoout'
  1017. (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
  1018. assumed.
  1019. For the CT69000 and SMI_LYNXEM drivers, videomode is
  1020. selected via environment 'videomode'. Two different ways
  1021. are possible:
  1022. - "videomode=num" 'num' is a standard LiLo mode numbers.
  1023. Following standard modes are supported (* is default):
  1024. Colors 640x480 800x600 1024x768 1152x864 1280x1024
  1025. -------------+---------------------------------------------
  1026. 8 bits | 0x301* 0x303 0x305 0x161 0x307
  1027. 15 bits | 0x310 0x313 0x316 0x162 0x319
  1028. 16 bits | 0x311 0x314 0x317 0x163 0x31A
  1029. 24 bits | 0x312 0x315 0x318 ? 0x31B
  1030. -------------+---------------------------------------------
  1031. (i.e. setenv videomode 317; saveenv; reset;)
  1032. - "videomode=bootargs" all the video parameters are parsed
  1033. from the bootargs. (See drivers/video/videomodes.c)
  1034. CONFIG_VIDEO_SED13806
  1035. Enable Epson SED13806 driver. This driver supports 8bpp
  1036. and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
  1037. or CONFIG_VIDEO_SED13806_16BPP
  1038. CONFIG_FSL_DIU_FB
  1039. Enable the Freescale DIU video driver. Reference boards for
  1040. SOCs that have a DIU should define this macro to enable DIU
  1041. support, and should also define these other macros:
  1042. CONFIG_SYS_DIU_ADDR
  1043. CONFIG_VIDEO
  1044. CONFIG_CMD_BMP
  1045. CONFIG_CFB_CONSOLE
  1046. CONFIG_VIDEO_SW_CURSOR
  1047. CONFIG_VGA_AS_SINGLE_DEVICE
  1048. CONFIG_VIDEO_LOGO
  1049. CONFIG_VIDEO_BMP_LOGO
  1050. The DIU driver will look for the 'video-mode' environment
  1051. variable, and if defined, enable the DIU as a console during
  1052. boot. See the documentation file README.video for a
  1053. description of this variable.
  1054. - Keyboard Support:
  1055. CONFIG_KEYBOARD
  1056. Define this to enable a custom keyboard support.
  1057. This simply calls drv_keyboard_init() which must be
  1058. defined in your board-specific files.
  1059. The only board using this so far is RBC823.
  1060. - LCD Support: CONFIG_LCD
  1061. Define this to enable LCD support (for output to LCD
  1062. display); also select one of the supported displays
  1063. by defining one of these:
  1064. CONFIG_ATMEL_LCD:
  1065. HITACHI TX09D70VM1CCA, 3.5", 240x320.
  1066. CONFIG_NEC_NL6448AC33:
  1067. NEC NL6448AC33-18. Active, color, single scan.
  1068. CONFIG_NEC_NL6448BC20
  1069. NEC NL6448BC20-08. 6.5", 640x480.
  1070. Active, color, single scan.
  1071. CONFIG_NEC_NL6448BC33_54
  1072. NEC NL6448BC33-54. 10.4", 640x480.
  1073. Active, color, single scan.
  1074. CONFIG_SHARP_16x9
  1075. Sharp 320x240. Active, color, single scan.
  1076. It isn't 16x9, and I am not sure what it is.
  1077. CONFIG_SHARP_LQ64D341
  1078. Sharp LQ64D341 display, 640x480.
  1079. Active, color, single scan.
  1080. CONFIG_HLD1045
  1081. HLD1045 display, 640x480.
  1082. Active, color, single scan.
  1083. CONFIG_OPTREX_BW
  1084. Optrex CBL50840-2 NF-FW 99 22 M5
  1085. or
  1086. Hitachi LMG6912RPFC-00T
  1087. or
  1088. Hitachi SP14Q002
  1089. 320x240. Black & white.
  1090. Normally display is black on white background; define
  1091. CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
  1092. - Splash Screen Support: CONFIG_SPLASH_SCREEN
  1093. If this option is set, the environment is checked for
  1094. a variable "splashimage". If found, the usual display
  1095. of logo, copyright and system information on the LCD
  1096. is suppressed and the BMP image at the address
  1097. specified in "splashimage" is loaded instead. The
  1098. console is redirected to the "nulldev", too. This
  1099. allows for a "silent" boot where a splash screen is
  1100. loaded very quickly after power-on.
  1101. CONFIG_SPLASH_SCREEN_ALIGN
  1102. If this option is set the splash image can be freely positioned
  1103. on the screen. Environment variable "splashpos" specifies the
  1104. position as "x,y". If a positive number is given it is used as
  1105. number of pixel from left/top. If a negative number is given it
  1106. is used as number of pixel from right/bottom. You can also
  1107. specify 'm' for centering the image.
  1108. Example:
  1109. setenv splashpos m,m
  1110. => image at center of screen
  1111. setenv splashpos 30,20
  1112. => image at x = 30 and y = 20
  1113. setenv splashpos -10,m
  1114. => vertically centered image
  1115. at x = dspWidth - bmpWidth - 9
  1116. - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
  1117. If this option is set, additionally to standard BMP
  1118. images, gzipped BMP images can be displayed via the
  1119. splashscreen support or the bmp command.
  1120. - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
  1121. If this option is set, 8-bit RLE compressed BMP images
  1122. can be displayed via the splashscreen support or the
  1123. bmp command.
  1124. - Compression support:
  1125. CONFIG_BZIP2
  1126. If this option is set, support for bzip2 compressed
  1127. images is included. If not, only uncompressed and gzip
  1128. compressed images are supported.
  1129. NOTE: the bzip2 algorithm requires a lot of RAM, so
  1130. the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
  1131. be at least 4MB.
  1132. CONFIG_LZMA
  1133. If this option is set, support for lzma compressed
  1134. images is included.
  1135. Note: The LZMA algorithm adds between 2 and 4KB of code and it
  1136. requires an amount of dynamic memory that is given by the
  1137. formula:
  1138. (1846 + 768 << (lc + lp)) * sizeof(uint16)
  1139. Where lc and lp stand for, respectively, Literal context bits
  1140. and Literal pos bits.
  1141. This value is upper-bounded by 14MB in the worst case. Anyway,
  1142. for a ~4MB large kernel image, we have lc=3 and lp=0 for a
  1143. total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
  1144. a very small buffer.
  1145. Use the lzmainfo tool to determinate the lc and lp values and
  1146. then calculate the amount of needed dynamic memory (ensuring
  1147. the appropriate CONFIG_SYS_MALLOC_LEN value).
  1148. - MII/PHY support:
  1149. CONFIG_PHY_ADDR
  1150. The address of PHY on MII bus.
  1151. CONFIG_PHY_CLOCK_FREQ (ppc4xx)
  1152. The clock frequency of the MII bus
  1153. CONFIG_PHY_GIGE
  1154. If this option is set, support for speed/duplex
  1155. detection of gigabit PHY is included.
  1156. CONFIG_PHY_RESET_DELAY
  1157. Some PHY like Intel LXT971A need extra delay after
  1158. reset before any MII register access is possible.
  1159. For such PHY, set this option to the usec delay
  1160. required. (minimum 300usec for LXT971A)
  1161. CONFIG_PHY_CMD_DELAY (ppc4xx)
  1162. Some PHY like Intel LXT971A need extra delay after
  1163. command issued before MII status register can be read
  1164. - Ethernet address:
  1165. CONFIG_ETHADDR
  1166. CONFIG_ETH1ADDR
  1167. CONFIG_ETH2ADDR
  1168. CONFIG_ETH3ADDR
  1169. CONFIG_ETH4ADDR
  1170. CONFIG_ETH5ADDR
  1171. Define a default value for Ethernet address to use
  1172. for the respective Ethernet interface, in case this
  1173. is not determined automatically.
  1174. - IP address:
  1175. CONFIG_IPADDR
  1176. Define a default value for the IP address to use for
  1177. the default Ethernet interface, in case this is not
  1178. determined through e.g. bootp.
  1179. (Environment variable "ipaddr")
  1180. - Server IP address:
  1181. CONFIG_SERVERIP
  1182. Defines a default value for the IP address of a TFTP
  1183. server to contact when using the "tftboot" command.
  1184. (Environment variable "serverip")
  1185. CONFIG_KEEP_SERVERADDR
  1186. Keeps the server's MAC address, in the env 'serveraddr'
  1187. for passing to bootargs (like Linux's netconsole option)
  1188. - Gateway IP address:
  1189. CONFIG_GATEWAYIP
  1190. Defines a default value for the IP address of the
  1191. default router where packets to other networks are
  1192. sent to.
  1193. (Environment variable "gatewayip")
  1194. - Subnet mask:
  1195. CONFIG_NETMASK
  1196. Defines a default value for the subnet mask (or
  1197. routing prefix) which is used to determine if an IP
  1198. address belongs to the local subnet or needs to be
  1199. forwarded through a router.
  1200. (Environment variable "netmask")
  1201. - Multicast TFTP Mode:
  1202. CONFIG_MCAST_TFTP
  1203. Defines whether you want to support multicast TFTP as per
  1204. rfc-2090; for example to work with atftp. Lets lots of targets
  1205. tftp down the same boot image concurrently. Note: the Ethernet
  1206. driver in use must provide a function: mcast() to join/leave a
  1207. multicast group.
  1208. - BOOTP Recovery Mode:
  1209. CONFIG_BOOTP_RANDOM_DELAY
  1210. If you have many targets in a network that try to
  1211. boot using BOOTP, you may want to avoid that all
  1212. systems send out BOOTP requests at precisely the same
  1213. moment (which would happen for instance at recovery
  1214. from a power failure, when all systems will try to
  1215. boot, thus flooding the BOOTP server. Defining
  1216. CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
  1217. inserted before sending out BOOTP requests. The
  1218. following delays are inserted then:
  1219. 1st BOOTP request: delay 0 ... 1 sec
  1220. 2nd BOOTP request: delay 0 ... 2 sec
  1221. 3rd BOOTP request: delay 0 ... 4 sec
  1222. 4th and following
  1223. BOOTP requests: delay 0 ... 8 sec
  1224. - DHCP Advanced Options:
  1225. You can fine tune the DHCP functionality by defining
  1226. CONFIG_BOOTP_* symbols:
  1227. CONFIG_BOOTP_SUBNETMASK
  1228. CONFIG_BOOTP_GATEWAY
  1229. CONFIG_BOOTP_HOSTNAME
  1230. CONFIG_BOOTP_NISDOMAIN
  1231. CONFIG_BOOTP_BOOTPATH
  1232. CONFIG_BOOTP_BOOTFILESIZE
  1233. CONFIG_BOOTP_DNS
  1234. CONFIG_BOOTP_DNS2
  1235. CONFIG_BOOTP_SEND_HOSTNAME
  1236. CONFIG_BOOTP_NTPSERVER
  1237. CONFIG_BOOTP_TIMEOFFSET
  1238. CONFIG_BOOTP_VENDOREX
  1239. CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
  1240. environment variable, not the BOOTP server.
  1241. CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
  1242. serverip from a DHCP server, it is possible that more
  1243. than one DNS serverip is offered to the client.
  1244. If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
  1245. serverip will be stored in the additional environment
  1246. variable "dnsip2". The first DNS serverip is always
  1247. stored in the variable "dnsip", when CONFIG_BOOTP_DNS
  1248. is defined.
  1249. CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
  1250. to do a dynamic update of a DNS server. To do this, they
  1251. need the hostname of the DHCP requester.
  1252. If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
  1253. of the "hostname" environment variable is passed as
  1254. option 12 to the DHCP server.
  1255. CONFIG_BOOTP_DHCP_REQUEST_DELAY
  1256. A 32bit value in microseconds for a delay between
  1257. receiving a "DHCP Offer" and sending the "DHCP Request".
  1258. This fixes a problem with certain DHCP servers that don't
  1259. respond 100% of the time to a "DHCP request". E.g. On an
  1260. AT91RM9200 processor running at 180MHz, this delay needed
  1261. to be *at least* 15,000 usec before a Windows Server 2003
  1262. DHCP server would reply 100% of the time. I recommend at
  1263. least 50,000 usec to be safe. The alternative is to hope
  1264. that one of the retries will be successful but note that
  1265. the DHCP timeout and retry process takes a longer than
  1266. this delay.
  1267. - CDP Options:
  1268. CONFIG_CDP_DEVICE_ID
  1269. The device id used in CDP trigger frames.
  1270. CONFIG_CDP_DEVICE_ID_PREFIX
  1271. A two character string which is prefixed to the MAC address
  1272. of the device.
  1273. CONFIG_CDP_PORT_ID
  1274. A printf format string which contains the ascii name of
  1275. the port. Normally is set to "eth%d" which sets
  1276. eth0 for the first Ethernet, eth1 for the second etc.
  1277. CONFIG_CDP_CAPABILITIES
  1278. A 32bit integer which indicates the device capabilities;
  1279. 0x00000010 for a normal host which does not forwards.
  1280. CONFIG_CDP_VERSION
  1281. An ascii string containing the version of the software.
  1282. CONFIG_CDP_PLATFORM
  1283. An ascii string containing the name of the platform.
  1284. CONFIG_CDP_TRIGGER
  1285. A 32bit integer sent on the trigger.
  1286. CONFIG_CDP_POWER_CONSUMPTION
  1287. A 16bit integer containing the power consumption of the
  1288. device in .1 of milliwatts.
  1289. CONFIG_CDP_APPLIANCE_VLAN_TYPE
  1290. A byte containing the id of the VLAN.
  1291. - Status LED: CONFIG_STATUS_LED
  1292. Several configurations allow to display the current
  1293. status using a LED. For instance, the LED will blink
  1294. fast while running U-Boot code, stop blinking as
  1295. soon as a reply to a BOOTP request was received, and
  1296. start blinking slow once the Linux kernel is running
  1297. (supported by a status LED driver in the Linux
  1298. kernel). Defining CONFIG_STATUS_LED enables this
  1299. feature in U-Boot.
  1300. - CAN Support: CONFIG_CAN_DRIVER
  1301. Defining CONFIG_CAN_DRIVER enables CAN driver support
  1302. on those systems that support this (optional)
  1303. feature, like the TQM8xxL modules.
  1304. - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
  1305. These enable I2C serial bus commands. Defining either of
  1306. (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
  1307. include the appropriate I2C driver for the selected CPU.
  1308. This will allow you to use i2c commands at the u-boot
  1309. command line (as long as you set CONFIG_CMD_I2C in
  1310. CONFIG_COMMANDS) and communicate with i2c based realtime
  1311. clock chips. See common/cmd_i2c.c for a description of the
  1312. command line interface.
  1313. CONFIG_HARD_I2C selects a hardware I2C controller.
  1314. CONFIG_SOFT_I2C configures u-boot to use a software (aka
  1315. bit-banging) driver instead of CPM or similar hardware
  1316. support for I2C.
  1317. There are several other quantities that must also be
  1318. defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
  1319. In both cases you will need to define CONFIG_SYS_I2C_SPEED
  1320. to be the frequency (in Hz) at which you wish your i2c bus
  1321. to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
  1322. the CPU's i2c node address).
  1323. Now, the u-boot i2c code for the mpc8xx
  1324. (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
  1325. and so its address should therefore be cleared to 0 (See,
  1326. eg, MPC823e User's Manual p.16-473). So, set
  1327. CONFIG_SYS_I2C_SLAVE to 0.
  1328. CONFIG_SYS_I2C_INIT_MPC5XXX
  1329. When a board is reset during an i2c bus transfer
  1330. chips might think that the current transfer is still
  1331. in progress. Reset the slave devices by sending start
  1332. commands until the slave device responds.
  1333. That's all that's required for CONFIG_HARD_I2C.
  1334. If you use the software i2c interface (CONFIG_SOFT_I2C)
  1335. then the following macros need to be defined (examples are
  1336. from include/configs/lwmon.h):
  1337. I2C_INIT
  1338. (Optional). Any commands necessary to enable the I2C
  1339. controller or configure ports.
  1340. eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
  1341. I2C_PORT
  1342. (Only for MPC8260 CPU). The I/O port to use (the code
  1343. assumes both bits are on the same port). Valid values
  1344. are 0..3 for ports A..D.
  1345. I2C_ACTIVE
  1346. The code necessary to make the I2C data line active
  1347. (driven). If the data line is open collector, this
  1348. define can be null.
  1349. eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
  1350. I2C_TRISTATE
  1351. The code necessary to make the I2C data line tri-stated
  1352. (inactive). If the data line is open collector, this
  1353. define can be null.
  1354. eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
  1355. I2C_READ
  1356. Code that returns TRUE if the I2C data line is high,
  1357. FALSE if it is low.
  1358. eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
  1359. I2C_SDA(bit)
  1360. If <bit> is TRUE, sets the I2C data line high. If it
  1361. is FALSE, it clears it (low).
  1362. eg: #define I2C_SDA(bit) \
  1363. if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
  1364. else immr->im_cpm.cp_pbdat &= ~PB_SDA
  1365. I2C_SCL(bit)
  1366. If <bit> is TRUE, sets the I2C clock line high. If it
  1367. is FALSE, it clears it (low).
  1368. eg: #define I2C_SCL(bit) \
  1369. if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
  1370. else immr->im_cpm.cp_pbdat &= ~PB_SCL
  1371. I2C_DELAY
  1372. This delay is invoked four times per clock cycle so this
  1373. controls the rate of data transfer. The data rate thus
  1374. is 1 / (I2C_DELAY * 4). Often defined to be something
  1375. like:
  1376. #define I2C_DELAY udelay(2)
  1377. CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
  1378. If your arch supports the generic GPIO framework (asm/gpio.h),
  1379. then you may alternatively define the two GPIOs that are to be
  1380. used as SCL / SDA. Any of the previous I2C_xxx macros will
  1381. have GPIO-based defaults assigned to them as appropriate.
  1382. You should define these to the GPIO value as given directly to
  1383. the generic GPIO functions.
  1384. CONFIG_SYS_I2C_INIT_BOARD
  1385. When a board is reset during an i2c bus transfer
  1386. chips might think that the current transfer is still
  1387. in progress. On some boards it is possible to access
  1388. the i2c SCLK line directly, either by using the
  1389. processor pin as a GPIO or by having a second pin
  1390. connected to the bus. If this option is defined a
  1391. custom i2c_init_board() routine in boards/xxx/board.c
  1392. is run early in the boot sequence.
  1393. CONFIG_SYS_I2C_BOARD_LATE_INIT
  1394. An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
  1395. defined a custom i2c_board_late_init() routine in
  1396. boards/xxx/board.c is run AFTER the operations in i2c_init()
  1397. is completed. This callpoint can be used to unreset i2c bus
  1398. using CPU i2c controller register accesses for CPUs whose i2c
  1399. controller provide such a method. It is called at the end of
  1400. i2c_init() to allow i2c_init operations to setup the i2c bus
  1401. controller on the CPU (e.g. setting bus speed & slave address).
  1402. CONFIG_I2CFAST (PPC405GP|PPC405EP only)
  1403. This option enables configuration of bi_iic_fast[] flags
  1404. in u-boot bd_info structure based on u-boot environment
  1405. variable "i2cfast". (see also i2cfast)
  1406. CONFIG_I2C_MULTI_BUS
  1407. This option allows the use of multiple I2C buses, each of which
  1408. must have a controller. At any point in time, only one bus is
  1409. active. To switch to a different bus, use the 'i2c dev' command.
  1410. Note that bus numbering is zero-based.
  1411. CONFIG_SYS_I2C_NOPROBES
  1412. This option specifies a list of I2C devices that will be skipped
  1413. when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
  1414. is set, specify a list of bus-device pairs. Otherwise, specify
  1415. a 1D array of device addresses
  1416. e.g.
  1417. #undef CONFIG_I2C_MULTI_BUS
  1418. #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
  1419. will skip addresses 0x50 and 0x68 on a board with one I2C bus
  1420. #define CONFIG_I2C_MULTI_BUS
  1421. #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
  1422. will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
  1423. CONFIG_SYS_SPD_BUS_NUM
  1424. If defined, then this indicates the I2C bus number for DDR SPD.
  1425. If not defined, then U-Boot assumes that SPD is on I2C bus 0.
  1426. CONFIG_SYS_RTC_BUS_NUM
  1427. If defined, then this indicates the I2C bus number for the RTC.
  1428. If not defined, then U-Boot assumes that RTC is on I2C bus 0.
  1429. CONFIG_SYS_DTT_BUS_NUM
  1430. If defined, then this indicates the I2C bus number for the DTT.
  1431. If not defined, then U-Boot assumes that DTT is on I2C bus 0.
  1432. CONFIG_SYS_I2C_DTT_ADDR:
  1433. If defined, specifies the I2C address of the DTT device.
  1434. If not defined, then U-Boot uses predefined value for
  1435. specified DTT device.
  1436. CONFIG_FSL_I2C
  1437. Define this option if you want to use Freescale's I2C driver in
  1438. drivers/i2c/fsl_i2c.c.
  1439. CONFIG_I2C_MUX
  1440. Define this option if you have I2C devices reached over 1 .. n
  1441. I2C Muxes like the pca9544a. This option addes a new I2C
  1442. Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a
  1443. new I2C Bus to the existing I2C Busses. If you select the
  1444. new Bus with "i2c dev", u-bbot sends first the commandos for
  1445. the muxes to activate this new "bus".
  1446. CONFIG_I2C_MULTI_BUS must be also defined, to use this
  1447. feature!
  1448. Example:
  1449. Adding a new I2C Bus reached over 2 pca9544a muxes
  1450. The First mux with address 70 and channel 6
  1451. The Second mux with address 71 and channel 4
  1452. => i2c bus pca9544a:70:6:pca9544a:71:4
  1453. Use the "i2c bus" command without parameter, to get a list
  1454. of I2C Busses with muxes:
  1455. => i2c bus
  1456. Busses reached over muxes:
  1457. Bus ID: 2
  1458. reached over Mux(es):
  1459. pca9544a@70 ch: 4
  1460. Bus ID: 3
  1461. reached over Mux(es):
  1462. pca9544a@70 ch: 6
  1463. pca9544a@71 ch: 4
  1464. =>
  1465. If you now switch to the new I2C Bus 3 with "i2c dev 3"
  1466. u-boot first sends the command to the mux@70 to enable
  1467. channel 6, and then the command to the mux@71 to enable
  1468. the channel 4.
  1469. After that, you can use the "normal" i2c commands as
  1470. usual to communicate with your I2C devices behind
  1471. the 2 muxes.
  1472. This option is actually implemented for the bitbanging
  1473. algorithm in common/soft_i2c.c and for the Hardware I2C
  1474. Bus on the MPC8260. But it should be not so difficult
  1475. to add this option to other architectures.
  1476. CONFIG_SOFT_I2C_READ_REPEATED_START
  1477. defining this will force the i2c_read() function in
  1478. the soft_i2c driver to perform an I2C repeated start
  1479. between writing the address pointer and reading the
  1480. data. If this define is omitted the default behaviour
  1481. of doing a stop-start sequence will be used. Most I2C
  1482. devices can use either method, but some require one or
  1483. the other.
  1484. - SPI Support: CONFIG_SPI
  1485. Enables SPI driver (so far only tested with
  1486. SPI EEPROM, also an instance works with Crystal A/D and
  1487. D/As on the SACSng board)
  1488. CONFIG_SH_SPI
  1489. Enables the driver for SPI controller on SuperH. Currently
  1490. only SH7757 is supported.
  1491. CONFIG_SPI_X
  1492. Enables extended (16-bit) SPI EEPROM addressing.
  1493. (symmetrical to CONFIG_I2C_X)
  1494. CONFIG_SOFT_SPI
  1495. Enables a software (bit-bang) SPI driver rather than
  1496. using hardware support. This is a general purpose
  1497. driver that only requires three general I/O port pins
  1498. (two outputs, one input) to function. If this is
  1499. defined, the board configuration must define several
  1500. SPI configuration items (port pins to use, etc). For
  1501. an example, see include/configs/sacsng.h.
  1502. CONFIG_HARD_SPI
  1503. Enables a hardware SPI driver for general-purpose reads
  1504. and writes. As with CONFIG_SOFT_SPI, the board configuration
  1505. must define a list of chip-select function pointers.
  1506. Currently supported on some MPC8xxx processors. For an
  1507. example, see include/configs/mpc8349emds.h.
  1508. CONFIG_MXC_SPI
  1509. Enables the driver for the SPI controllers on i.MX and MXC
  1510. SoCs. Currently i.MX31/35/51 are supported.
  1511. - FPGA Support: CONFIG_FPGA
  1512. Enables FPGA subsystem.
  1513. CONFIG_FPGA_<vendor>
  1514. Enables support for specific chip vendors.
  1515. (ALTERA, XILINX)
  1516. CONFIG_FPGA_<family>
  1517. Enables support for FPGA family.
  1518. (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
  1519. CONFIG_FPGA_COUNT
  1520. Specify the number of FPGA devices to support.
  1521. CONFIG_SYS_FPGA_PROG_FEEDBACK
  1522. Enable printing of hash marks during FPGA configuration.
  1523. CONFIG_SYS_FPGA_CHECK_BUSY
  1524. Enable checks on FPGA configuration interface busy
  1525. status by the configuration function. This option
  1526. will require a board or device specific function to
  1527. be written.
  1528. CONFIG_FPGA_DELAY
  1529. If defined, a function that provides delays in the FPGA
  1530. configuration driver.
  1531. CONFIG_SYS_FPGA_CHECK_CTRLC
  1532. Allow Control-C to interrupt FPGA configuration
  1533. CONFIG_SYS_FPGA_CHECK_ERROR
  1534. Check for configuration errors during FPGA bitfile
  1535. loading. For example, abort during Virtex II
  1536. configuration if the INIT_B line goes low (which
  1537. indicated a CRC error).
  1538. CONFIG_SYS_FPGA_WAIT_INIT
  1539. Maximum time to wait for the INIT_B line to deassert
  1540. after PROB_B has been deasserted during a Virtex II
  1541. FPGA configuration sequence. The default time is 500
  1542. ms.
  1543. CONFIG_SYS_FPGA_WAIT_BUSY
  1544. Maximum time to wait for BUSY to deassert during
  1545. Virtex II FPGA configuration. The default is 5 ms.
  1546. CONFIG_SYS_FPGA_WAIT_CONFIG
  1547. Time to wait after FPGA configuration. The default is
  1548. 200 ms.
  1549. - Configuration Management:
  1550. CONFIG_IDENT_STRING
  1551. If defined, this string will be added to the U-Boot
  1552. version information (U_BOOT_VERSION)
  1553. - Vendor Parameter Protection:
  1554. U-Boot considers the values of the environment
  1555. variables "serial#" (Board Serial Number) and
  1556. "ethaddr" (Ethernet Address) to be parameters that
  1557. are set once by the board vendor / manufacturer, and
  1558. protects these variables from casual modification by
  1559. the user. Once set, these variables are read-only,
  1560. and write or delete attempts are rejected. You can
  1561. change this behaviour:
  1562. If CONFIG_ENV_OVERWRITE is #defined in your config
  1563. file, the write protection for vendor parameters is
  1564. completely disabled. Anybody can change or delete
  1565. these parameters.
  1566. Alternatively, if you #define _both_ CONFIG_ETHADDR
  1567. _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
  1568. Ethernet address is installed in the environment,
  1569. which can be changed exactly ONCE by the user. [The
  1570. serial# is unaffected by this, i. e. it remains
  1571. read-only.]
  1572. - Protected RAM:
  1573. CONFIG_PRAM
  1574. Define this variable to enable the reservation of
  1575. "protected RAM", i. e. RAM which is not overwritten
  1576. by U-Boot. Define CONFIG_PRAM to hold the number of
  1577. kB you want to reserve for pRAM. You can overwrite
  1578. this default value by defining an environment
  1579. variable "pram" to the number of kB you want to
  1580. reserve. Note that the board info structure will
  1581. still show the full amount of RAM. If pRAM is
  1582. reserved, a new environment variable "mem" will
  1583. automatically be defined to hold the amount of
  1584. remaining RAM in a form that can be passed as boot
  1585. argument to Linux, for instance like that:
  1586. setenv bootargs ... mem=\${mem}
  1587. saveenv
  1588. This way you can tell Linux not to use this memory,
  1589. either, which results in a memory region that will
  1590. not be affected by reboots.
  1591. *WARNING* If your board configuration uses automatic
  1592. detection of the RAM size, you must make sure that
  1593. this memory test is non-destructive. So far, the
  1594. following board configurations are known to be
  1595. "pRAM-clean":
  1596. ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
  1597. HERMES, IP860, RPXlite, LWMON, LANTEC,
  1598. FLAGADM, TQM8260
  1599. - Error Recovery:
  1600. CONFIG_PANIC_HANG
  1601. Define this variable to stop the system in case of a
  1602. fatal error, so that you have to reset it manually.
  1603. This is probably NOT a good idea for an embedded
  1604. system where you want the system to reboot
  1605. automatically as fast as possible, but it may be
  1606. useful during development since you can try to debug
  1607. the conditions that lead to the situation.
  1608. CONFIG_NET_RETRY_COUNT
  1609. This variable defines the number of retries for
  1610. network operations like ARP, RARP, TFTP, or BOOTP
  1611. before giving up the operation. If not defined, a
  1612. default value of 5 is used.
  1613. CONFIG_ARP_TIMEOUT
  1614. Timeout waiting for an ARP reply in milliseconds.
  1615. - Command Interpreter:
  1616. CONFIG_AUTO_COMPLETE
  1617. Enable auto completion of commands using TAB.
  1618. Note that this feature has NOT been implemented yet
  1619. for the "hush" shell.
  1620. CONFIG_SYS_HUSH_PARSER
  1621. Define this variable to enable the "hush" shell (from
  1622. Busybox) as command line interpreter, thus enabling
  1623. powerful command line syntax like
  1624. if...then...else...fi conditionals or `&&' and '||'
  1625. constructs ("shell scripts").
  1626. If undefined, you get the old, much simpler behaviour
  1627. with a somewhat smaller memory footprint.
  1628. CONFIG_SYS_PROMPT_HUSH_PS2
  1629. This defines the secondary prompt string, which is
  1630. printed when the command interpreter needs more input
  1631. to complete a command. Usually "> ".
  1632. Note:
  1633. In the current implementation, the local variables
  1634. space and global environment variables space are
  1635. separated. Local variables are those you define by
  1636. simply typing `name=value'. To access a local
  1637. variable later on, you have write `$name' or
  1638. `${name}'; to execute the contents of a variable
  1639. directly type `$name' at the command prompt.
  1640. Global environment variables are those you use
  1641. setenv/printenv to work with. To run a command stored
  1642. in such a variable, you need to use the run command,
  1643. and you must not use the '$' sign to access them.
  1644. To store commands and special characters in a
  1645. variable, please use double quotation marks
  1646. surrounding the whole text of the variable, instead
  1647. of the backslashes before semicolons and special
  1648. symbols.
  1649. - Commandline Editing and History:
  1650. CONFIG_CMDLINE_EDITING
  1651. Enable editing and History functions for interactive
  1652. commandline input operations
  1653. - Default Environment:
  1654. CONFIG_EXTRA_ENV_SETTINGS
  1655. Define this to contain any number of null terminated
  1656. strings (variable = value pairs) that will be part of
  1657. the default environment compiled into the boot image.
  1658. For example, place something like this in your
  1659. board's config file:
  1660. #define CONFIG_EXTRA_ENV_SETTINGS \
  1661. "myvar1=value1\0" \
  1662. "myvar2=value2\0"
  1663. Warning: This method is based on knowledge about the
  1664. internal format how the environment is stored by the
  1665. U-Boot code. This is NOT an official, exported
  1666. interface! Although it is unlikely that this format
  1667. will change soon, there is no guarantee either.
  1668. You better know what you are doing here.
  1669. Note: overly (ab)use of the default environment is
  1670. discouraged. Make sure to check other ways to preset
  1671. the environment like the "source" command or the
  1672. boot command first.
  1673. - DataFlash Support:
  1674. CONFIG_HAS_DATAFLASH
  1675. Defining this option enables DataFlash features and
  1676. allows to read/write in Dataflash via the standard
  1677. commands cp, md...
  1678. - Serial Flash support
  1679. CONFIG_CMD_SF
  1680. Defining this option enables SPI flash commands
  1681. 'sf probe/read/write/erase/update'.
  1682. Usage requires an initial 'probe' to define the serial
  1683. flash parameters, followed by read/write/erase/update
  1684. commands.
  1685. The following defaults may be provided by the platform
  1686. to handle the common case when only a single serial
  1687. flash is present on the system.
  1688. CONFIG_SF_DEFAULT_BUS Bus identifier
  1689. CONFIG_SF_DEFAULT_CS Chip-select
  1690. CONFIG_SF_DEFAULT_MODE (see include/spi.h)
  1691. CONFIG_SF_DEFAULT_SPEED in Hz
  1692. - SystemACE Support:
  1693. CONFIG_SYSTEMACE
  1694. Adding this option adds support for Xilinx SystemACE
  1695. chips attached via some sort of local bus. The address
  1696. of the chip must also be defined in the
  1697. CONFIG_SYS_SYSTEMACE_BASE macro. For example:
  1698. #define CONFIG_SYSTEMACE
  1699. #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
  1700. When SystemACE support is added, the "ace" device type
  1701. becomes available to the fat commands, i.e. fatls.
  1702. - TFTP Fixed UDP Port:
  1703. CONFIG_TFTP_PORT
  1704. If this is defined, the environment variable tftpsrcp
  1705. is used to supply the TFTP UDP source port value.
  1706. If tftpsrcp isn't defined, the normal pseudo-random port
  1707. number generator is used.
  1708. Also, the environment variable tftpdstp is used to supply
  1709. the TFTP UDP destination port value. If tftpdstp isn't
  1710. defined, the normal port 69 is used.
  1711. The purpose for tftpsrcp is to allow a TFTP server to
  1712. blindly start the TFTP transfer using the pre-configured
  1713. target IP address and UDP port. This has the effect of
  1714. "punching through" the (Windows XP) firewall, allowing
  1715. the remainder of the TFTP transfer to proceed normally.
  1716. A better solution is to properly configure the firewall,
  1717. but sometimes that is not allowed.
  1718. - Show boot progress:
  1719. CONFIG_SHOW_BOOT_PROGRESS
  1720. Defining this option allows to add some board-
  1721. specific code (calling a user-provided function
  1722. "show_boot_progress(int)") that enables you to show
  1723. the system's boot progress on some display (for
  1724. example, some LED's) on your board. At the moment,
  1725. the following checkpoints are implemented:
  1726. - Detailed boot stage timing
  1727. CONFIG_BOOTSTAGE
  1728. Define this option to get detailed timing of each stage
  1729. of the boot process.
  1730. CONFIG_BOOTSTAGE_USER_COUNT
  1731. This is the number of available user bootstage records.
  1732. Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...)
  1733. a new ID will be allocated from this stash. If you exceed
  1734. the limit, recording will stop.
  1735. CONFIG_BOOTSTAGE_REPORT
  1736. Define this to print a report before boot, similar to this:
  1737. Timer summary in microseconds:
  1738. Mark Elapsed Stage
  1739. 0 0 reset
  1740. 3,575,678 3,575,678 board_init_f start
  1741. 3,575,695 17 arch_cpu_init A9
  1742. 3,575,777 82 arch_cpu_init done
  1743. 3,659,598 83,821 board_init_r start
  1744. 3,910,375 250,777 main_loop
  1745. 29,916,167 26,005,792 bootm_start
  1746. 30,361,327 445,160 start_kernel
  1747. Legacy uImage format:
  1748. Arg Where When
  1749. 1 common/cmd_bootm.c before attempting to boot an image
  1750. -1 common/cmd_bootm.c Image header has bad magic number
  1751. 2 common/cmd_bootm.c Image header has correct magic number
  1752. -2 common/cmd_bootm.c Image header has bad checksum
  1753. 3 common/cmd_bootm.c Image header has correct checksum
  1754. -3 common/cmd_bootm.c Image data has bad checksum
  1755. 4 common/cmd_bootm.c Image data has correct checksum
  1756. -4 common/cmd_bootm.c Image is for unsupported architecture
  1757. 5 common/cmd_bootm.c Architecture check OK
  1758. -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
  1759. 6 common/cmd_bootm.c Image Type check OK
  1760. -6 common/cmd_bootm.c gunzip uncompression error
  1761. -7 common/cmd_bootm.c Unimplemented compression type
  1762. 7 common/cmd_bootm.c Uncompression OK
  1763. 8 common/cmd_bootm.c No uncompress/copy overwrite error
  1764. -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
  1765. 9 common/image.c Start initial ramdisk verification
  1766. -10 common/image.c Ramdisk header has bad magic number
  1767. -11 common/image.c Ramdisk header has bad checksum
  1768. 10 common/image.c Ramdisk header is OK
  1769. -12 common/image.c Ramdisk data has bad checksum
  1770. 11 common/image.c Ramdisk data has correct checksum
  1771. 12 common/image.c Ramdisk verification complete, start loading
  1772. -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
  1773. 13 common/image.c Start multifile image verification
  1774. 14 common/image.c No initial ramdisk, no multifile, continue.
  1775. 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
  1776. -30 arch/powerpc/lib/board.c Fatal error, hang the system
  1777. -31 post/post.c POST test failed, detected by post_output_backlog()
  1778. -32 post/post.c POST test failed, detected by post_run_single()
  1779. 34 common/cmd_doc.c before loading a Image from a DOC device
  1780. -35 common/cmd_doc.c Bad usage of "doc" command
  1781. 35 common/cmd_doc.c correct usage of "doc" command
  1782. -36 common/cmd_doc.c No boot device
  1783. 36 common/cmd_doc.c correct boot device
  1784. -37 common/cmd_doc.c Unknown Chip ID on boot device
  1785. 37 common/cmd_doc.c correct chip ID found, device available
  1786. -38 common/cmd_doc.c Read Error on boot device
  1787. 38 common/cmd_doc.c reading Image header from DOC device OK
  1788. -39 common/cmd_doc.c Image header has bad magic number
  1789. 39 common/cmd_doc.c Image header has correct magic number
  1790. -40 common/cmd_doc.c Error reading Image from DOC device
  1791. 40 common/cmd_doc.c Image header has correct magic number
  1792. 41 common/cmd_ide.c before loading a Image from a IDE device
  1793. -42 common/cmd_ide.c Bad usage of "ide" command
  1794. 42 common/cmd_ide.c correct usage of "ide" command
  1795. -43 common/cmd_ide.c No boot device
  1796. 43 common/cmd_ide.c boot device found
  1797. -44 common/cmd_ide.c Device not available
  1798. 44 common/cmd_ide.c Device available
  1799. -45 common/cmd_ide.c wrong partition selected
  1800. 45 common/cmd_ide.c partition selected
  1801. -46 common/cmd_ide.c Unknown partition table
  1802. 46 common/cmd_ide.c valid partition table found
  1803. -47 common/cmd_ide.c Invalid partition type
  1804. 47 common/cmd_ide.c correct partition type
  1805. -48 common/cmd_ide.c Error reading Image Header on boot device
  1806. 48 common/cmd_ide.c reading Image Header from IDE device OK
  1807. -49 common/cmd_ide.c Image header has bad magic number
  1808. 49 common/cmd_ide.c Image header has correct magic number
  1809. -50 common/cmd_ide.c Image header has bad checksum
  1810. 50 common/cmd_ide.c Image header has correct checksum
  1811. -51 common/cmd_ide.c Error reading Image from IDE device
  1812. 51 common/cmd_ide.c reading Image from IDE device OK
  1813. 52 common/cmd_nand.c before loading a Image from a NAND device
  1814. -53 common/cmd_nand.c Bad usage of "nand" command
  1815. 53 common/cmd_nand.c correct usage of "nand" command
  1816. -54 common/cmd_nand.c No boot device
  1817. 54 common/cmd_nand.c boot device found
  1818. -55 common/cmd_nand.c Unknown Chip ID on boot device
  1819. 55 common/cmd_nand.c correct chip ID found, device available
  1820. -56 common/cmd_nand.c Error reading Image Header on boot device
  1821. 56 common/cmd_nand.c reading Image Header from NAND device OK
  1822. -57 common/cmd_nand.c Image header has bad magic number
  1823. 57 common/cmd_nand.c Image header has correct magic number
  1824. -58 common/cmd_nand.c Error reading Image from NAND device
  1825. 58 common/cmd_nand.c reading Image from NAND device OK
  1826. -60 common/env_common.c Environment has a bad CRC, using default
  1827. 64 net/eth.c starting with Ethernet configuration.
  1828. -64 net/eth.c no Ethernet found.
  1829. 65 net/eth.c Ethernet found.
  1830. -80 common/cmd_net.c usage wrong
  1831. 80 common/cmd_net.c before calling NetLoop()
  1832. -81 common/cmd_net.c some error in NetLoop() occurred
  1833. 81 common/cmd_net.c NetLoop() back without error
  1834. -82 common/cmd_net.c size == 0 (File with size 0 loaded)
  1835. 82 common/cmd_net.c trying automatic boot
  1836. 83 common/cmd_net.c running "source" command
  1837. -83 common/cmd_net.c some error in automatic boot or "source" command
  1838. 84 common/cmd_net.c end without errors
  1839. FIT uImage format:
  1840. Arg Where When
  1841. 100 common/cmd_bootm.c Kernel FIT Image has correct format
  1842. -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
  1843. 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
  1844. -101 common/cmd_bootm.c Can't get configuration for kernel subimage
  1845. 102 common/cmd_bootm.c Kernel unit name specified
  1846. -103 common/cmd_bootm.c Can't get kernel subimage node offset
  1847. 103 common/cmd_bootm.c Found configuration node
  1848. 104 common/cmd_bootm.c Got kernel subimage node offset
  1849. -104 common/cmd_bootm.c Kernel subimage hash verification failed
  1850. 105 common/cmd_bootm.c Kernel subimage hash verification OK
  1851. -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
  1852. 106 common/cmd_bootm.c Architecture check OK
  1853. -106 common/cmd_bootm.c Kernel subimage has wrong type
  1854. 107 common/cmd_bootm.c Kernel subimage type OK
  1855. -107 common/cmd_bootm.c Can't get kernel subimage data/size
  1856. 108 common/cmd_bootm.c Got kernel subimage data/size
  1857. -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
  1858. -109 common/cmd_bootm.c Can't get kernel subimage type
  1859. -110 common/cmd_bootm.c Can't get kernel subimage comp
  1860. -111 common/cmd_bootm.c Can't get kernel subimage os
  1861. -112 common/cmd_bootm.c Can't get kernel subimage load address
  1862. -113 common/cmd_bootm.c Image uncompress/copy overwrite error
  1863. 120 common/image.c Start initial ramdisk verification
  1864. -120 common/image.c Ramdisk FIT image has incorrect format
  1865. 121 common/image.c Ramdisk FIT image has correct format
  1866. 122 common/image.c No ramdisk subimage unit name, using configuration
  1867. -122 common/image.c Can't get configuration for ramdisk subimage
  1868. 123 common/image.c Ramdisk unit name specified
  1869. -124 common/image.c Can't get ramdisk subimage node offset
  1870. 125 common/image.c Got ramdisk subimage node offset
  1871. -125 common/image.c Ramdisk subimage hash verification failed
  1872. 126 common/image.c Ramdisk subimage hash verification OK
  1873. -126 common/image.c Ramdisk subimage for unsupported architecture
  1874. 127 common/image.c Architecture check OK
  1875. -127 common/image.c Can't get ramdisk subimage data/size
  1876. 128 common/image.c Got ramdisk subimage data/size
  1877. 129 common/image.c Can't get ramdisk load address
  1878. -129 common/image.c Got ramdisk load address
  1879. -130 common/cmd_doc.c Incorrect FIT image format
  1880. 131 common/cmd_doc.c FIT image format OK
  1881. -140 common/cmd_ide.c Incorrect FIT image format
  1882. 141 common/cmd_ide.c FIT image format OK
  1883. -150 common/cmd_nand.c Incorrect FIT image format
  1884. 151 common/cmd_nand.c FIT image format OK
  1885. - Standalone program support:
  1886. CONFIG_STANDALONE_LOAD_ADDR
  1887. This option defines a board specific value for the
  1888. address where standalone program gets loaded, thus
  1889. overwriting the architecture dependent default
  1890. settings.
  1891. - Frame Buffer Address:
  1892. CONFIG_FB_ADDR
  1893. Define CONFIG_FB_ADDR if you want to use specific
  1894. address for frame buffer.
  1895. Then system will reserve the frame buffer address to
  1896. defined address instead of lcd_setmem (this function
  1897. grabs the memory for frame buffer by panel's size).
  1898. Please see board_init_f function.
  1899. - Automatic software updates via TFTP server
  1900. CONFIG_UPDATE_TFTP
  1901. CONFIG_UPDATE_TFTP_CNT_MAX
  1902. CONFIG_UPDATE_TFTP_MSEC_MAX
  1903. These options enable and control the auto-update feature;
  1904. for a more detailed description refer to doc/README.update.
  1905. - MTD Support (mtdparts command, UBI support)
  1906. CONFIG_MTD_DEVICE
  1907. Adds the MTD device infrastructure from the Linux kernel.
  1908. Needed for mtdparts command support.
  1909. CONFIG_MTD_PARTITIONS
  1910. Adds the MTD partitioning infrastructure from the Linux
  1911. kernel. Needed for UBI support.
  1912. - SPL framework
  1913. CONFIG_SPL
  1914. Enable building of SPL globally.
  1915. CONFIG_SPL_LDSCRIPT
  1916. LDSCRIPT for linking the SPL binary.
  1917. CONFIG_SPL_MAX_SIZE
  1918. Maximum binary size (text, data and rodata) of the SPL binary.
  1919. CONFIG_SPL_TEXT_BASE
  1920. TEXT_BASE for linking the SPL binary.
  1921. CONFIG_SPL_BSS_START_ADDR
  1922. Link address for the BSS within the SPL binary.
  1923. CONFIG_SPL_BSS_MAX_SIZE
  1924. Maximum binary size of the BSS section of the SPL binary.
  1925. CONFIG_SPL_STACK
  1926. Adress of the start of the stack SPL will use
  1927. CONFIG_SYS_SPL_MALLOC_START
  1928. Starting address of the malloc pool used in SPL.
  1929. CONFIG_SYS_SPL_MALLOC_SIZE
  1930. The size of the malloc pool used in SPL.
  1931. CONFIG_SPL_LIBCOMMON_SUPPORT
  1932. Support for common/libcommon.o in SPL binary
  1933. CONFIG_SPL_LIBDISK_SUPPORT
  1934. Support for disk/libdisk.o in SPL binary
  1935. CONFIG_SPL_I2C_SUPPORT
  1936. Support for drivers/i2c/libi2c.o in SPL binary
  1937. CONFIG_SPL_GPIO_SUPPORT
  1938. Support for drivers/gpio/libgpio.o in SPL binary
  1939. CONFIG_SPL_MMC_SUPPORT
  1940. Support for drivers/mmc/libmmc.o in SPL binary
  1941. CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR,
  1942. CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS,
  1943. CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION
  1944. Address, size and partition on the MMC to load U-Boot from
  1945. when the MMC is being used in raw mode.
  1946. CONFIG_SPL_FAT_SUPPORT
  1947. Support for fs/fat/libfat.o in SPL binary
  1948. CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME
  1949. Filename to read to load U-Boot when reading from FAT
  1950. CONFIG_SPL_NAND_SIMPLE
  1951. Support for drivers/mtd/nand/libnand.o in SPL binary
  1952. CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
  1953. CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
  1954. CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
  1955. CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
  1956. CONFIG_SYS_NAND_ECCBYTES
  1957. Defines the size and behavior of the NAND that SPL uses
  1958. to read U-Boot with CONFIG_SPL_NAND_SIMPLE
  1959. CONFIG_SYS_NAND_U_BOOT_OFFS
  1960. Location in NAND for CONFIG_SPL_NAND_SIMPLE to read U-Boot
  1961. from.
  1962. CONFIG_SYS_NAND_U_BOOT_START
  1963. Location in memory for CONFIG_SPL_NAND_SIMPLE to load U-Boot
  1964. to.
  1965. CONFIG_SYS_NAND_HW_ECC_OOBFIRST
  1966. Define this if you need to first read the OOB and then the
  1967. data. This is used for example on davinci plattforms.
  1968. CONFIG_SPL_OMAP3_ID_NAND
  1969. Support for an OMAP3-specific set of functions to return the
  1970. ID and MFR of the first attached NAND chip, if present.
  1971. CONFIG_SPL_SERIAL_SUPPORT
  1972. Support for drivers/serial/libserial.o in SPL binary
  1973. CONFIG_SPL_SPI_FLASH_SUPPORT
  1974. Support for drivers/mtd/spi/libspi_flash.o in SPL binary
  1975. CONFIG_SPL_SPI_SUPPORT
  1976. Support for drivers/spi/libspi.o in SPL binary
  1977. CONFIG_SPL_LIBGENERIC_SUPPORT
  1978. Support for lib/libgeneric.o in SPL binary
  1979. Modem Support:
  1980. --------------
  1981. [so far only for SMDK2400 boards]
  1982. - Modem support enable:
  1983. CONFIG_MODEM_SUPPORT
  1984. - RTS/CTS Flow control enable:
  1985. CONFIG_HWFLOW
  1986. - Modem debug support:
  1987. CONFIG_MODEM_SUPPORT_DEBUG
  1988. Enables debugging stuff (char screen[1024], dbg())
  1989. for modem support. Useful only with BDI2000.
  1990. - Interrupt support (PPC):
  1991. There are common interrupt_init() and timer_interrupt()
  1992. for all PPC archs. interrupt_init() calls interrupt_init_cpu()
  1993. for CPU specific initialization. interrupt_init_cpu()
  1994. should set decrementer_count to appropriate value. If
  1995. CPU resets decrementer automatically after interrupt
  1996. (ppc4xx) it should set decrementer_count to zero.
  1997. timer_interrupt() calls timer_interrupt_cpu() for CPU
  1998. specific handling. If board has watchdog / status_led
  1999. / other_activity_monitor it works automatically from
  2000. general timer_interrupt().
  2001. - General:
  2002. In the target system modem support is enabled when a
  2003. specific key (key combination) is pressed during
  2004. power-on. Otherwise U-Boot will boot normally
  2005. (autoboot). The key_pressed() function is called from
  2006. board_init(). Currently key_pressed() is a dummy
  2007. function, returning 1 and thus enabling modem
  2008. initialization.
  2009. If there are no modem init strings in the
  2010. environment, U-Boot proceed to autoboot; the
  2011. previous output (banner, info printfs) will be
  2012. suppressed, though.
  2013. See also: doc/README.Modem
  2014. Board initialization settings:
  2015. ------------------------------
  2016. During Initialization u-boot calls a number of board specific functions
  2017. to allow the preparation of board specific prerequisites, e.g. pin setup
  2018. before drivers are initialized. To enable these callbacks the
  2019. following configuration macros have to be defined. Currently this is
  2020. architecture specific, so please check arch/your_architecture/lib/board.c
  2021. typically in board_init_f() and board_init_r().
  2022. - CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
  2023. - CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
  2024. - CONFIG_BOARD_LATE_INIT: Call board_late_init()
  2025. - CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
  2026. Configuration Settings:
  2027. -----------------------
  2028. - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
  2029. undefine this when you're short of memory.
  2030. - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
  2031. width of the commands listed in the 'help' command output.
  2032. - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
  2033. prompt for user input.
  2034. - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
  2035. - CONFIG_SYS_PBSIZE: Buffer size for Console output
  2036. - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
  2037. - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
  2038. the application (usually a Linux kernel) when it is
  2039. booted
  2040. - CONFIG_SYS_BAUDRATE_TABLE:
  2041. List of legal baudrate settings for this board.
  2042. - CONFIG_SYS_CONSOLE_INFO_QUIET
  2043. Suppress display of console information at boot.
  2044. - CONFIG_SYS_CONSOLE_IS_IN_ENV
  2045. If the board specific function
  2046. extern int overwrite_console (void);
  2047. returns 1, the stdin, stderr and stdout are switched to the
  2048. serial port, else the settings in the environment are used.
  2049. - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
  2050. Enable the call to overwrite_console().
  2051. - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
  2052. Enable overwrite of previous console environment settings.
  2053. - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
  2054. Begin and End addresses of the area used by the
  2055. simple memory test.
  2056. - CONFIG_SYS_ALT_MEMTEST:
  2057. Enable an alternate, more extensive memory test.
  2058. - CONFIG_SYS_MEMTEST_SCRATCH:
  2059. Scratch address used by the alternate memory test
  2060. You only need to set this if address zero isn't writeable
  2061. - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
  2062. If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
  2063. this specified memory area will get subtracted from the top
  2064. (end) of RAM and won't get "touched" at all by U-Boot. By
  2065. fixing up gd->ram_size the Linux kernel should gets passed
  2066. the now "corrected" memory size and won't touch it either.
  2067. This should work for arch/ppc and arch/powerpc. Only Linux
  2068. board ports in arch/powerpc with bootwrapper support that
  2069. recalculate the memory size from the SDRAM controller setup
  2070. will have to get fixed in Linux additionally.
  2071. This option can be used as a workaround for the 440EPx/GRx
  2072. CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
  2073. be touched.
  2074. WARNING: Please make sure that this value is a multiple of
  2075. the Linux page size (normally 4k). If this is not the case,
  2076. then the end address of the Linux memory will be located at a
  2077. non page size aligned address and this could cause major
  2078. problems.
  2079. - CONFIG_SYS_TFTP_LOADADDR:
  2080. Default load address for network file downloads
  2081. - CONFIG_SYS_LOADS_BAUD_CHANGE:
  2082. Enable temporary baudrate change while serial download
  2083. - CONFIG_SYS_SDRAM_BASE:
  2084. Physical start address of SDRAM. _Must_ be 0 here.
  2085. - CONFIG_SYS_MBIO_BASE:
  2086. Physical start address of Motherboard I/O (if using a
  2087. Cogent motherboard)
  2088. - CONFIG_SYS_FLASH_BASE:
  2089. Physical start address of Flash memory.
  2090. - CONFIG_SYS_MONITOR_BASE:
  2091. Physical start address of boot monitor code (set by
  2092. make config files to be same as the text base address
  2093. (CONFIG_SYS_TEXT_BASE) used when linking) - same as
  2094. CONFIG_SYS_FLASH_BASE when booting from flash.
  2095. - CONFIG_SYS_MONITOR_LEN:
  2096. Size of memory reserved for monitor code, used to
  2097. determine _at_compile_time_ (!) if the environment is
  2098. embedded within the U-Boot image, or in a separate
  2099. flash sector.
  2100. - CONFIG_SYS_MALLOC_LEN:
  2101. Size of DRAM reserved for malloc() use.
  2102. - CONFIG_SYS_BOOTM_LEN:
  2103. Normally compressed uImages are limited to an
  2104. uncompressed size of 8 MBytes. If this is not enough,
  2105. you can define CONFIG_SYS_BOOTM_LEN in your board config file
  2106. to adjust this setting to your needs.
  2107. - CONFIG_SYS_BOOTMAPSZ:
  2108. Maximum size of memory mapped by the startup code of
  2109. the Linux kernel; all data that must be processed by
  2110. the Linux kernel (bd_info, boot arguments, FDT blob if
  2111. used) must be put below this limit, unless "bootm_low"
  2112. enviroment variable is defined and non-zero. In such case
  2113. all data for the Linux kernel must be between "bootm_low"
  2114. and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
  2115. variable "bootm_mapsize" will override the value of
  2116. CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
  2117. then the value in "bootm_size" will be used instead.
  2118. - CONFIG_SYS_BOOT_RAMDISK_HIGH:
  2119. Enable initrd_high functionality. If defined then the
  2120. initrd_high feature is enabled and the bootm ramdisk subcommand
  2121. is enabled.
  2122. - CONFIG_SYS_BOOT_GET_CMDLINE:
  2123. Enables allocating and saving kernel cmdline in space between
  2124. "bootm_low" and "bootm_low" + BOOTMAPSZ.
  2125. - CONFIG_SYS_BOOT_GET_KBD:
  2126. Enables allocating and saving a kernel copy of the bd_info in
  2127. space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
  2128. - CONFIG_SYS_MAX_FLASH_BANKS:
  2129. Max number of Flash memory banks
  2130. - CONFIG_SYS_MAX_FLASH_SECT:
  2131. Max number of sectors on a Flash chip
  2132. - CONFIG_SYS_FLASH_ERASE_TOUT:
  2133. Timeout for Flash erase operations (in ms)
  2134. - CONFIG_SYS_FLASH_WRITE_TOUT:
  2135. Timeout for Flash write operations (in ms)
  2136. - CONFIG_SYS_FLASH_LOCK_TOUT
  2137. Timeout for Flash set sector lock bit operation (in ms)
  2138. - CONFIG_SYS_FLASH_UNLOCK_TOUT
  2139. Timeout for Flash clear lock bits operation (in ms)
  2140. - CONFIG_SYS_FLASH_PROTECTION
  2141. If defined, hardware flash sectors protection is used
  2142. instead of U-Boot software protection.
  2143. - CONFIG_SYS_DIRECT_FLASH_TFTP:
  2144. Enable TFTP transfers directly to flash memory;
  2145. without this option such a download has to be
  2146. performed in two steps: (1) download to RAM, and (2)
  2147. copy from RAM to flash.
  2148. The two-step approach is usually more reliable, since
  2149. you can check if the download worked before you erase
  2150. the flash, but in some situations (when system RAM is
  2151. too limited to allow for a temporary copy of the
  2152. downloaded image) this option may be very useful.
  2153. - CONFIG_SYS_FLASH_CFI:
  2154. Define if the flash driver uses extra elements in the
  2155. common flash structure for storing flash geometry.
  2156. - CONFIG_FLASH_CFI_DRIVER
  2157. This option also enables the building of the cfi_flash driver
  2158. in the drivers directory
  2159. - CONFIG_FLASH_CFI_MTD
  2160. This option enables the building of the cfi_mtd driver
  2161. in the drivers directory. The driver exports CFI flash
  2162. to the MTD layer.
  2163. - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
  2164. Use buffered writes to flash.
  2165. - CONFIG_FLASH_SPANSION_S29WS_N
  2166. s29ws-n MirrorBit flash has non-standard addresses for buffered
  2167. write commands.
  2168. - CONFIG_SYS_FLASH_QUIET_TEST
  2169. If this option is defined, the common CFI flash doesn't
  2170. print it's warning upon not recognized FLASH banks. This
  2171. is useful, if some of the configured banks are only
  2172. optionally available.
  2173. - CONFIG_FLASH_SHOW_PROGRESS
  2174. If defined (must be an integer), print out countdown
  2175. digits and dots. Recommended value: 45 (9..1) for 80
  2176. column displays, 15 (3..1) for 40 column displays.
  2177. - CONFIG_SYS_RX_ETH_BUFFER:
  2178. Defines the number of Ethernet receive buffers. On some
  2179. Ethernet controllers it is recommended to set this value
  2180. to 8 or even higher (EEPRO100 or 405 EMAC), since all
  2181. buffers can be full shortly after enabling the interface
  2182. on high Ethernet traffic.
  2183. Defaults to 4 if not defined.
  2184. - CONFIG_ENV_MAX_ENTRIES
  2185. Maximum number of entries in the hash table that is used
  2186. internally to store the environment settings. The default
  2187. setting is supposed to be generous and should work in most
  2188. cases. This setting can be used to tune behaviour; see
  2189. lib/hashtable.c for details.
  2190. The following definitions that deal with the placement and management
  2191. of environment data (variable area); in general, we support the
  2192. following configurations:
  2193. - CONFIG_BUILD_ENVCRC:
  2194. Builds up envcrc with the target environment so that external utils
  2195. may easily extract it and embed it in final U-Boot images.
  2196. - CONFIG_ENV_IS_IN_FLASH:
  2197. Define this if the environment is in flash memory.
  2198. a) The environment occupies one whole flash sector, which is
  2199. "embedded" in the text segment with the U-Boot code. This
  2200. happens usually with "bottom boot sector" or "top boot
  2201. sector" type flash chips, which have several smaller
  2202. sectors at the start or the end. For instance, such a
  2203. layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
  2204. such a case you would place the environment in one of the
  2205. 4 kB sectors - with U-Boot code before and after it. With
  2206. "top boot sector" type flash chips, you would put the
  2207. environment in one of the last sectors, leaving a gap
  2208. between U-Boot and the environment.
  2209. - CONFIG_ENV_OFFSET:
  2210. Offset of environment data (variable area) to the
  2211. beginning of flash memory; for instance, with bottom boot
  2212. type flash chips the second sector can be used: the offset
  2213. for this sector is given here.
  2214. CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
  2215. - CONFIG_ENV_ADDR:
  2216. This is just another way to specify the start address of
  2217. the flash sector containing the environment (instead of
  2218. CONFIG_ENV_OFFSET).
  2219. - CONFIG_ENV_SECT_SIZE:
  2220. Size of the sector containing the environment.
  2221. b) Sometimes flash chips have few, equal sized, BIG sectors.
  2222. In such a case you don't want to spend a whole sector for
  2223. the environment.
  2224. - CONFIG_ENV_SIZE:
  2225. If you use this in combination with CONFIG_ENV_IS_IN_FLASH
  2226. and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
  2227. of this flash sector for the environment. This saves
  2228. memory for the RAM copy of the environment.
  2229. It may also save flash memory if you decide to use this
  2230. when your environment is "embedded" within U-Boot code,
  2231. since then the remainder of the flash sector could be used
  2232. for U-Boot code. It should be pointed out that this is
  2233. STRONGLY DISCOURAGED from a robustness point of view:
  2234. updating the environment in flash makes it always
  2235. necessary to erase the WHOLE sector. If something goes
  2236. wrong before the contents has been restored from a copy in
  2237. RAM, your target system will be dead.
  2238. - CONFIG_ENV_ADDR_REDUND
  2239. CONFIG_ENV_SIZE_REDUND
  2240. These settings describe a second storage area used to hold
  2241. a redundant copy of the environment data, so that there is
  2242. a valid backup copy in case there is a power failure during
  2243. a "saveenv" operation.
  2244. BE CAREFUL! Any changes to the flash layout, and some changes to the
  2245. source code will make it necessary to adapt <board>/u-boot.lds*
  2246. accordingly!
  2247. - CONFIG_ENV_IS_IN_NVRAM:
  2248. Define this if you have some non-volatile memory device
  2249. (NVRAM, battery buffered SRAM) which you want to use for the
  2250. environment.
  2251. - CONFIG_ENV_ADDR:
  2252. - CONFIG_ENV_SIZE:
  2253. These two #defines are used to determine the memory area you
  2254. want to use for environment. It is assumed that this memory
  2255. can just be read and written to, without any special
  2256. provision.
  2257. BE CAREFUL! The first access to the environment happens quite early
  2258. in U-Boot initalization (when we try to get the setting of for the
  2259. console baudrate). You *MUST* have mapped your NVRAM area then, or
  2260. U-Boot will hang.
  2261. Please note that even with NVRAM we still use a copy of the
  2262. environment in RAM: we could work on NVRAM directly, but we want to
  2263. keep settings there always unmodified except somebody uses "saveenv"
  2264. to save the current settings.
  2265. - CONFIG_ENV_IS_IN_EEPROM:
  2266. Use this if you have an EEPROM or similar serial access
  2267. device and a driver for it.
  2268. - CONFIG_ENV_OFFSET:
  2269. - CONFIG_ENV_SIZE:
  2270. These two #defines specify the offset and size of the
  2271. environment area within the total memory of your EEPROM.
  2272. - CONFIG_SYS_I2C_EEPROM_ADDR:
  2273. If defined, specified the chip address of the EEPROM device.
  2274. The default address is zero.
  2275. - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
  2276. If defined, the number of bits used to address bytes in a
  2277. single page in the EEPROM device. A 64 byte page, for example
  2278. would require six bits.
  2279. - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
  2280. If defined, the number of milliseconds to delay between
  2281. page writes. The default is zero milliseconds.
  2282. - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
  2283. The length in bytes of the EEPROM memory array address. Note
  2284. that this is NOT the chip address length!
  2285. - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
  2286. EEPROM chips that implement "address overflow" are ones
  2287. like Catalyst 24WC04/08/16 which has 9/10/11 bits of
  2288. address and the extra bits end up in the "chip address" bit
  2289. slots. This makes a 24WC08 (1Kbyte) chip look like four 256
  2290. byte chips.
  2291. Note that we consider the length of the address field to
  2292. still be one byte because the extra address bits are hidden
  2293. in the chip address.
  2294. - CONFIG_SYS_EEPROM_SIZE:
  2295. The size in bytes of the EEPROM device.
  2296. - CONFIG_ENV_EEPROM_IS_ON_I2C
  2297. define this, if you have I2C and SPI activated, and your
  2298. EEPROM, which holds the environment, is on the I2C bus.
  2299. - CONFIG_I2C_ENV_EEPROM_BUS
  2300. if you have an Environment on an EEPROM reached over
  2301. I2C muxes, you can define here, how to reach this
  2302. EEPROM. For example:
  2303. #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0"
  2304. EEPROM which holds the environment, is reached over
  2305. a pca9547 i2c mux with address 0x70, channel 3.
  2306. - CONFIG_ENV_IS_IN_DATAFLASH:
  2307. Define this if you have a DataFlash memory device which you
  2308. want to use for the environment.
  2309. - CONFIG_ENV_OFFSET:
  2310. - CONFIG_ENV_ADDR:
  2311. - CONFIG_ENV_SIZE:
  2312. These three #defines specify the offset and size of the
  2313. environment area within the total memory of your DataFlash placed
  2314. at the specified address.
  2315. - CONFIG_ENV_IS_IN_NAND:
  2316. Define this if you have a NAND device which you want to use
  2317. for the environment.
  2318. - CONFIG_ENV_OFFSET:
  2319. - CONFIG_ENV_SIZE:
  2320. These two #defines specify the offset and size of the environment
  2321. area within the first NAND device. CONFIG_ENV_OFFSET must be
  2322. aligned to an erase block boundary.
  2323. - CONFIG_ENV_OFFSET_REDUND (optional):
  2324. This setting describes a second storage area of CONFIG_ENV_SIZE
  2325. size used to hold a redundant copy of the environment data, so
  2326. that there is a valid backup copy in case there is a power failure
  2327. during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
  2328. aligned to an erase block boundary.
  2329. - CONFIG_ENV_RANGE (optional):
  2330. Specifies the length of the region in which the environment
  2331. can be written. This should be a multiple of the NAND device's
  2332. block size. Specifying a range with more erase blocks than
  2333. are needed to hold CONFIG_ENV_SIZE allows bad blocks within
  2334. the range to be avoided.
  2335. - CONFIG_ENV_OFFSET_OOB (optional):
  2336. Enables support for dynamically retrieving the offset of the
  2337. environment from block zero's out-of-band data. The
  2338. "nand env.oob" command can be used to record this offset.
  2339. Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
  2340. using CONFIG_ENV_OFFSET_OOB.
  2341. - CONFIG_NAND_ENV_DST
  2342. Defines address in RAM to which the nand_spl code should copy the
  2343. environment. If redundant environment is used, it will be copied to
  2344. CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
  2345. - CONFIG_SYS_SPI_INIT_OFFSET
  2346. Defines offset to the initial SPI buffer area in DPRAM. The
  2347. area is used at an early stage (ROM part) if the environment
  2348. is configured to reside in the SPI EEPROM: We need a 520 byte
  2349. scratch DPRAM area. It is used between the two initialization
  2350. calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
  2351. to be a good choice since it makes it far enough from the
  2352. start of the data area as well as from the stack pointer.
  2353. Please note that the environment is read-only until the monitor
  2354. has been relocated to RAM and a RAM copy of the environment has been
  2355. created; also, when using EEPROM you will have to use getenv_f()
  2356. until then to read environment variables.
  2357. The environment is protected by a CRC32 checksum. Before the monitor
  2358. is relocated into RAM, as a result of a bad CRC you will be working
  2359. with the compiled-in default environment - *silently*!!! [This is
  2360. necessary, because the first environment variable we need is the
  2361. "baudrate" setting for the console - if we have a bad CRC, we don't
  2362. have any device yet where we could complain.]
  2363. Note: once the monitor has been relocated, then it will complain if
  2364. the default environment is used; a new CRC is computed as soon as you
  2365. use the "saveenv" command to store a valid environment.
  2366. - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
  2367. Echo the inverted Ethernet link state to the fault LED.
  2368. Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
  2369. also needs to be defined.
  2370. - CONFIG_SYS_FAULT_MII_ADDR:
  2371. MII address of the PHY to check for the Ethernet link state.
  2372. - CONFIG_NS16550_MIN_FUNCTIONS:
  2373. Define this if you desire to only have use of the NS16550_init
  2374. and NS16550_putc functions for the serial driver located at
  2375. drivers/serial/ns16550.c. This option is useful for saving
  2376. space for already greatly restricted images, including but not
  2377. limited to NAND_SPL configurations.
  2378. Low Level (hardware related) configuration options:
  2379. ---------------------------------------------------
  2380. - CONFIG_SYS_CACHELINE_SIZE:
  2381. Cache Line Size of the CPU.
  2382. - CONFIG_SYS_DEFAULT_IMMR:
  2383. Default address of the IMMR after system reset.
  2384. Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
  2385. and RPXsuper) to be able to adjust the position of
  2386. the IMMR register after a reset.
  2387. - CONFIG_SYS_CCSRBAR_DEFAULT:
  2388. Default (power-on reset) physical address of CCSR on Freescale
  2389. PowerPC SOCs.
  2390. - CONFIG_SYS_CCSRBAR:
  2391. Virtual address of CCSR. On a 32-bit build, this is typically
  2392. the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
  2393. CONFIG_SYS_DEFAULT_IMMR must also be set to this value,
  2394. for cross-platform code that uses that macro instead.
  2395. - CONFIG_SYS_CCSRBAR_PHYS:
  2396. Physical address of CCSR. CCSR can be relocated to a new
  2397. physical address, if desired. In this case, this macro should
  2398. be set to that address. Otherwise, it should be set to the
  2399. same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
  2400. is typically relocated on 36-bit builds. It is recommended
  2401. that this macro be defined via the _HIGH and _LOW macros:
  2402. #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
  2403. * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
  2404. - CONFIG_SYS_CCSRBAR_PHYS_HIGH:
  2405. Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
  2406. either 0 (32-bit build) or 0xF (36-bit build). This macro is
  2407. used in assembly code, so it must not contain typecasts or
  2408. integer size suffixes (e.g. "ULL").
  2409. - CONFIG_SYS_CCSRBAR_PHYS_LOW:
  2410. Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
  2411. used in assembly code, so it must not contain typecasts or
  2412. integer size suffixes (e.g. "ULL").
  2413. - CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
  2414. If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
  2415. forced to a value that ensures that CCSR is not relocated.
  2416. - Floppy Disk Support:
  2417. CONFIG_SYS_FDC_DRIVE_NUMBER
  2418. the default drive number (default value 0)
  2419. CONFIG_SYS_ISA_IO_STRIDE
  2420. defines the spacing between FDC chipset registers
  2421. (default value 1)
  2422. CONFIG_SYS_ISA_IO_OFFSET
  2423. defines the offset of register from address. It
  2424. depends on which part of the data bus is connected to
  2425. the FDC chipset. (default value 0)
  2426. If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
  2427. CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
  2428. default value.
  2429. if CONFIG_SYS_FDC_HW_INIT is defined, then the function
  2430. fdc_hw_init() is called at the beginning of the FDC
  2431. setup. fdc_hw_init() must be provided by the board
  2432. source code. It is used to make hardware dependant
  2433. initializations.
  2434. - CONFIG_IDE_AHB:
  2435. Most IDE controllers were designed to be connected with PCI
  2436. interface. Only few of them were designed for AHB interface.
  2437. When software is doing ATA command and data transfer to
  2438. IDE devices through IDE-AHB controller, some additional
  2439. registers accessing to these kind of IDE-AHB controller
  2440. is requierd.
  2441. - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
  2442. DO NOT CHANGE unless you know exactly what you're
  2443. doing! (11-4) [MPC8xx/82xx systems only]
  2444. - CONFIG_SYS_INIT_RAM_ADDR:
  2445. Start address of memory area that can be used for
  2446. initial data and stack; please note that this must be
  2447. writable memory that is working WITHOUT special
  2448. initialization, i. e. you CANNOT use normal RAM which
  2449. will become available only after programming the
  2450. memory controller and running certain initialization
  2451. sequences.
  2452. U-Boot uses the following memory types:
  2453. - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
  2454. - MPC824X: data cache
  2455. - PPC4xx: data cache
  2456. - CONFIG_SYS_GBL_DATA_OFFSET:
  2457. Offset of the initial data structure in the memory
  2458. area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
  2459. CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
  2460. data is located at the end of the available space
  2461. (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
  2462. CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
  2463. below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
  2464. CONFIG_SYS_GBL_DATA_OFFSET) downward.
  2465. Note:
  2466. On the MPC824X (or other systems that use the data
  2467. cache for initial memory) the address chosen for
  2468. CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
  2469. point to an otherwise UNUSED address space between
  2470. the top of RAM and the start of the PCI space.
  2471. - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
  2472. - CONFIG_SYS_SYPCR: System Protection Control (11-9)
  2473. - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
  2474. - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
  2475. - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
  2476. - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
  2477. - CONFIG_SYS_OR_TIMING_SDRAM:
  2478. SDRAM timing
  2479. - CONFIG_SYS_MAMR_PTA:
  2480. periodic timer for refresh
  2481. - CONFIG_SYS_DER: Debug Event Register (37-47)
  2482. - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
  2483. CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
  2484. CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
  2485. CONFIG_SYS_BR1_PRELIM:
  2486. Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
  2487. - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
  2488. CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
  2489. CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
  2490. Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
  2491. - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
  2492. CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
  2493. Machine Mode Register and Memory Periodic Timer
  2494. Prescaler definitions (SDRAM timing)
  2495. - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
  2496. enable I2C microcode relocation patch (MPC8xx);
  2497. define relocation offset in DPRAM [DSP2]
  2498. - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
  2499. enable SMC microcode relocation patch (MPC8xx);
  2500. define relocation offset in DPRAM [SMC1]
  2501. - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
  2502. enable SPI microcode relocation patch (MPC8xx);
  2503. define relocation offset in DPRAM [SCC4]
  2504. - CONFIG_SYS_USE_OSCCLK:
  2505. Use OSCM clock mode on MBX8xx board. Be careful,
  2506. wrong setting might damage your board. Read
  2507. doc/README.MBX before setting this variable!
  2508. - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
  2509. Offset of the bootmode word in DPRAM used by post
  2510. (Power On Self Tests). This definition overrides
  2511. #define'd default value in commproc.h resp.
  2512. cpm_8260.h.
  2513. - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
  2514. CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
  2515. CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
  2516. CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
  2517. CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
  2518. CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
  2519. CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
  2520. CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
  2521. Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
  2522. - CONFIG_PCI_DISABLE_PCIE:
  2523. Disable PCI-Express on systems where it is supported but not
  2524. required.
  2525. - CONFIG_SYS_SRIO:
  2526. Chip has SRIO or not
  2527. - CONFIG_SRIO1:
  2528. Board has SRIO 1 port available
  2529. - CONFIG_SRIO2:
  2530. Board has SRIO 2 port available
  2531. - CONFIG_SYS_SRIOn_MEM_VIRT:
  2532. Virtual Address of SRIO port 'n' memory region
  2533. - CONFIG_SYS_SRIOn_MEM_PHYS:
  2534. Physical Address of SRIO port 'n' memory region
  2535. - CONFIG_SYS_SRIOn_MEM_SIZE:
  2536. Size of SRIO port 'n' memory region
  2537. - CONFIG_SYS_NDFC_16
  2538. Defined to tell the NDFC that the NAND chip is using a
  2539. 16 bit bus.
  2540. - CONFIG_SYS_NDFC_EBC0_CFG
  2541. Sets the EBC0_CFG register for the NDFC. If not defined
  2542. a default value will be used.
  2543. - CONFIG_SPD_EEPROM
  2544. Get DDR timing information from an I2C EEPROM. Common
  2545. with pluggable memory modules such as SODIMMs
  2546. SPD_EEPROM_ADDRESS
  2547. I2C address of the SPD EEPROM
  2548. - CONFIG_SYS_SPD_BUS_NUM
  2549. If SPD EEPROM is on an I2C bus other than the first
  2550. one, specify here. Note that the value must resolve
  2551. to something your driver can deal with.
  2552. - CONFIG_SYS_DDR_RAW_TIMING
  2553. Get DDR timing information from other than SPD. Common with
  2554. soldered DDR chips onboard without SPD. DDR raw timing
  2555. parameters are extracted from datasheet and hard-coded into
  2556. header files or board specific files.
  2557. - CONFIG_FSL_DDR_INTERACTIVE
  2558. Enable interactive DDR debugging. See doc/README.fsl-ddr.
  2559. - CONFIG_SYS_83XX_DDR_USES_CS0
  2560. Only for 83xx systems. If specified, then DDR should
  2561. be configured using CS0 and CS1 instead of CS2 and CS3.
  2562. - CONFIG_ETHER_ON_FEC[12]
  2563. Define to enable FEC[12] on a 8xx series processor.
  2564. - CONFIG_FEC[12]_PHY
  2565. Define to the hardcoded PHY address which corresponds
  2566. to the given FEC; i. e.
  2567. #define CONFIG_FEC1_PHY 4
  2568. means that the PHY with address 4 is connected to FEC1
  2569. When set to -1, means to probe for first available.
  2570. - CONFIG_FEC[12]_PHY_NORXERR
  2571. The PHY does not have a RXERR line (RMII only).
  2572. (so program the FEC to ignore it).
  2573. - CONFIG_RMII
  2574. Enable RMII mode for all FECs.
  2575. Note that this is a global option, we can't
  2576. have one FEC in standard MII mode and another in RMII mode.
  2577. - CONFIG_CRC32_VERIFY
  2578. Add a verify option to the crc32 command.
  2579. The syntax is:
  2580. => crc32 -v <address> <count> <crc32>
  2581. Where address/count indicate a memory area
  2582. and crc32 is the correct crc32 which the
  2583. area should have.
  2584. - CONFIG_LOOPW
  2585. Add the "loopw" memory command. This only takes effect if
  2586. the memory commands are activated globally (CONFIG_CMD_MEM).
  2587. - CONFIG_MX_CYCLIC
  2588. Add the "mdc" and "mwc" memory commands. These are cyclic
  2589. "md/mw" commands.
  2590. Examples:
  2591. => mdc.b 10 4 500
  2592. This command will print 4 bytes (10,11,12,13) each 500 ms.
  2593. => mwc.l 100 12345678 10
  2594. This command will write 12345678 to address 100 all 10 ms.
  2595. This only takes effect if the memory commands are activated
  2596. globally (CONFIG_CMD_MEM).
  2597. - CONFIG_SKIP_LOWLEVEL_INIT
  2598. [ARM, NDS32, MIPS only] If this variable is defined, then certain
  2599. low level initializations (like setting up the memory
  2600. controller) are omitted and/or U-Boot does not
  2601. relocate itself into RAM.
  2602. Normally this variable MUST NOT be defined. The only
  2603. exception is when U-Boot is loaded (to RAM) by some
  2604. other boot loader or by a debugger which performs
  2605. these initializations itself.
  2606. - CONFIG_SPL_BUILD
  2607. Modifies the behaviour of start.S when compiling a loader
  2608. that is executed before the actual U-Boot. E.g. when
  2609. compiling a NAND SPL.
  2610. - CONFIG_USE_ARCH_MEMCPY
  2611. CONFIG_USE_ARCH_MEMSET
  2612. If these options are used a optimized version of memcpy/memset will
  2613. be used if available. These functions may be faster under some
  2614. conditions but may increase the binary size.
  2615. Freescale QE/FMAN Firmware Support:
  2616. -----------------------------------
  2617. The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
  2618. loading of "firmware", which is encoded in the QE firmware binary format.
  2619. This firmware often needs to be loaded during U-Boot booting, so macros
  2620. are used to identify the storage device (NOR flash, SPI, etc) and the address
  2621. within that device.
  2622. - CONFIG_SYS_QE_FMAN_FW_ADDR
  2623. The address in the storage device where the firmware is located. The
  2624. meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
  2625. is also specified.
  2626. - CONFIG_SYS_QE_FMAN_FW_LENGTH
  2627. The maximum possible size of the firmware. The firmware binary format
  2628. has a field that specifies the actual size of the firmware, but it
  2629. might not be possible to read any part of the firmware unless some
  2630. local storage is allocated to hold the entire firmware first.
  2631. - CONFIG_SYS_QE_FMAN_FW_IN_NOR
  2632. Specifies that QE/FMAN firmware is located in NOR flash, mapped as
  2633. normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
  2634. virtual address in NOR flash.
  2635. - CONFIG_SYS_QE_FMAN_FW_IN_NAND
  2636. Specifies that QE/FMAN firmware is located in NAND flash.
  2637. CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
  2638. - CONFIG_SYS_QE_FMAN_FW_IN_MMC
  2639. Specifies that QE/FMAN firmware is located on the primary SD/MMC
  2640. device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
  2641. - CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH
  2642. Specifies that QE/FMAN firmware is located on the primary SPI
  2643. device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
  2644. Building the Software:
  2645. ======================
  2646. Building U-Boot has been tested in several native build environments
  2647. and in many different cross environments. Of course we cannot support
  2648. all possibly existing versions of cross development tools in all
  2649. (potentially obsolete) versions. In case of tool chain problems we
  2650. recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
  2651. which is extensively used to build and test U-Boot.
  2652. If you are not using a native environment, it is assumed that you
  2653. have GNU cross compiling tools available in your path. In this case,
  2654. you must set the environment variable CROSS_COMPILE in your shell.
  2655. Note that no changes to the Makefile or any other source files are
  2656. necessary. For example using the ELDK on a 4xx CPU, please enter:
  2657. $ CROSS_COMPILE=ppc_4xx-
  2658. $ export CROSS_COMPILE
  2659. Note: If you wish to generate Windows versions of the utilities in
  2660. the tools directory you can use the MinGW toolchain
  2661. (http://www.mingw.org). Set your HOST tools to the MinGW
  2662. toolchain and execute 'make tools'. For example:
  2663. $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
  2664. Binaries such as tools/mkimage.exe will be created which can
  2665. be executed on computers running Windows.
  2666. U-Boot is intended to be simple to build. After installing the
  2667. sources you must configure U-Boot for one specific board type. This
  2668. is done by typing:
  2669. make NAME_config
  2670. where "NAME_config" is the name of one of the existing configu-
  2671. rations; see the main Makefile for supported names.
  2672. Note: for some board special configuration names may exist; check if
  2673. additional information is available from the board vendor; for
  2674. instance, the TQM823L systems are available without (standard)
  2675. or with LCD support. You can select such additional "features"
  2676. when choosing the configuration, i. e.
  2677. make TQM823L_config
  2678. - will configure for a plain TQM823L, i. e. no LCD support
  2679. make TQM823L_LCD_config
  2680. - will configure for a TQM823L with U-Boot console on LCD
  2681. etc.
  2682. Finally, type "make all", and you should get some working U-Boot
  2683. images ready for download to / installation on your system:
  2684. - "u-boot.bin" is a raw binary image
  2685. - "u-boot" is an image in ELF binary format
  2686. - "u-boot.srec" is in Motorola S-Record format
  2687. By default the build is performed locally and the objects are saved
  2688. in the source directory. One of the two methods can be used to change
  2689. this behavior and build U-Boot to some external directory:
  2690. 1. Add O= to the make command line invocations:
  2691. make O=/tmp/build distclean
  2692. make O=/tmp/build NAME_config
  2693. make O=/tmp/build all
  2694. 2. Set environment variable BUILD_DIR to point to the desired location:
  2695. export BUILD_DIR=/tmp/build
  2696. make distclean
  2697. make NAME_config
  2698. make all
  2699. Note that the command line "O=" setting overrides the BUILD_DIR environment
  2700. variable.
  2701. Please be aware that the Makefiles assume you are using GNU make, so
  2702. for instance on NetBSD you might need to use "gmake" instead of
  2703. native "make".
  2704. If the system board that you have is not listed, then you will need
  2705. to port U-Boot to your hardware platform. To do this, follow these
  2706. steps:
  2707. 1. Add a new configuration option for your board to the toplevel
  2708. "Makefile" and to the "MAKEALL" script, using the existing
  2709. entries as examples. Note that here and at many other places
  2710. boards and other names are listed in alphabetical sort order. Please
  2711. keep this order.
  2712. 2. Create a new directory to hold your board specific code. Add any
  2713. files you need. In your board directory, you will need at least
  2714. the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
  2715. 3. Create a new configuration file "include/configs/<board>.h" for
  2716. your board
  2717. 3. If you're porting U-Boot to a new CPU, then also create a new
  2718. directory to hold your CPU specific code. Add any files you need.
  2719. 4. Run "make <board>_config" with your new name.
  2720. 5. Type "make", and you should get a working "u-boot.srec" file
  2721. to be installed on your target system.
  2722. 6. Debug and solve any problems that might arise.
  2723. [Of course, this last step is much harder than it sounds.]
  2724. Testing of U-Boot Modifications, Ports to New Hardware, etc.:
  2725. ==============================================================
  2726. If you have modified U-Boot sources (for instance added a new board
  2727. or support for new devices, a new CPU, etc.) you are expected to
  2728. provide feedback to the other developers. The feedback normally takes
  2729. the form of a "patch", i. e. a context diff against a certain (latest
  2730. official or latest in the git repository) version of U-Boot sources.
  2731. But before you submit such a patch, please verify that your modifi-
  2732. cation did not break existing code. At least make sure that *ALL* of
  2733. the supported boards compile WITHOUT ANY compiler warnings. To do so,
  2734. just run the "MAKEALL" script, which will configure and build U-Boot
  2735. for ALL supported system. Be warned, this will take a while. You can
  2736. select which (cross) compiler to use by passing a `CROSS_COMPILE'
  2737. environment variable to the script, i. e. to use the ELDK cross tools
  2738. you can type
  2739. CROSS_COMPILE=ppc_8xx- MAKEALL
  2740. or to build on a native PowerPC system you can type
  2741. CROSS_COMPILE=' ' MAKEALL
  2742. When using the MAKEALL script, the default behaviour is to build
  2743. U-Boot in the source directory. This location can be changed by
  2744. setting the BUILD_DIR environment variable. Also, for each target
  2745. built, the MAKEALL script saves two log files (<target>.ERR and
  2746. <target>.MAKEALL) in the <source dir>/LOG directory. This default
  2747. location can be changed by setting the MAKEALL_LOGDIR environment
  2748. variable. For example:
  2749. export BUILD_DIR=/tmp/build
  2750. export MAKEALL_LOGDIR=/tmp/log
  2751. CROSS_COMPILE=ppc_8xx- MAKEALL
  2752. With the above settings build objects are saved in the /tmp/build,
  2753. log files are saved in the /tmp/log and the source tree remains clean
  2754. during the whole build process.
  2755. See also "U-Boot Porting Guide" below.
  2756. Monitor Commands - Overview:
  2757. ============================
  2758. go - start application at address 'addr'
  2759. run - run commands in an environment variable
  2760. bootm - boot application image from memory
  2761. bootp - boot image via network using BootP/TFTP protocol
  2762. tftpboot- boot image via network using TFTP protocol
  2763. and env variables "ipaddr" and "serverip"
  2764. (and eventually "gatewayip")
  2765. tftpput - upload a file via network using TFTP protocol
  2766. rarpboot- boot image via network using RARP/TFTP protocol
  2767. diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
  2768. loads - load S-Record file over serial line
  2769. loadb - load binary file over serial line (kermit mode)
  2770. md - memory display
  2771. mm - memory modify (auto-incrementing)
  2772. nm - memory modify (constant address)
  2773. mw - memory write (fill)
  2774. cp - memory copy
  2775. cmp - memory compare
  2776. crc32 - checksum calculation
  2777. i2c - I2C sub-system
  2778. sspi - SPI utility commands
  2779. base - print or set address offset
  2780. printenv- print environment variables
  2781. setenv - set environment variables
  2782. saveenv - save environment variables to persistent storage
  2783. protect - enable or disable FLASH write protection
  2784. erase - erase FLASH memory
  2785. flinfo - print FLASH memory information
  2786. bdinfo - print Board Info structure
  2787. iminfo - print header information for application image
  2788. coninfo - print console devices and informations
  2789. ide - IDE sub-system
  2790. loop - infinite loop on address range
  2791. loopw - infinite write loop on address range
  2792. mtest - simple RAM test
  2793. icache - enable or disable instruction cache
  2794. dcache - enable or disable data cache
  2795. reset - Perform RESET of the CPU
  2796. echo - echo args to console
  2797. version - print monitor version
  2798. help - print online help
  2799. ? - alias for 'help'
  2800. Monitor Commands - Detailed Description:
  2801. ========================================
  2802. TODO.
  2803. For now: just type "help <command>".
  2804. Environment Variables:
  2805. ======================
  2806. U-Boot supports user configuration using Environment Variables which
  2807. can be made persistent by saving to Flash memory.
  2808. Environment Variables are set using "setenv", printed using
  2809. "printenv", and saved to Flash using "saveenv". Using "setenv"
  2810. without a value can be used to delete a variable from the
  2811. environment. As long as you don't save the environment you are
  2812. working with an in-memory copy. In case the Flash area containing the
  2813. environment is erased by accident, a default environment is provided.
  2814. Some configuration options can be set using Environment Variables.
  2815. List of environment variables (most likely not complete):
  2816. baudrate - see CONFIG_BAUDRATE
  2817. bootdelay - see CONFIG_BOOTDELAY
  2818. bootcmd - see CONFIG_BOOTCOMMAND
  2819. bootargs - Boot arguments when booting an RTOS image
  2820. bootfile - Name of the image to load with TFTP
  2821. bootm_low - Memory range available for image processing in the bootm
  2822. command can be restricted. This variable is given as
  2823. a hexadecimal number and defines lowest address allowed
  2824. for use by the bootm command. See also "bootm_size"
  2825. environment variable. Address defined by "bootm_low" is
  2826. also the base of the initial memory mapping for the Linux
  2827. kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
  2828. bootm_mapsize.
  2829. bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
  2830. This variable is given as a hexadecimal number and it
  2831. defines the size of the memory region starting at base
  2832. address bootm_low that is accessible by the Linux kernel
  2833. during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
  2834. as the default value if it is defined, and bootm_size is
  2835. used otherwise.
  2836. bootm_size - Memory range available for image processing in the bootm
  2837. command can be restricted. This variable is given as
  2838. a hexadecimal number and defines the size of the region
  2839. allowed for use by the bootm command. See also "bootm_low"
  2840. environment variable.
  2841. updatefile - Location of the software update file on a TFTP server, used
  2842. by the automatic software update feature. Please refer to
  2843. documentation in doc/README.update for more details.
  2844. autoload - if set to "no" (any string beginning with 'n'),
  2845. "bootp" will just load perform a lookup of the
  2846. configuration from the BOOTP server, but not try to
  2847. load any image using TFTP
  2848. autostart - if set to "yes", an image loaded using the "bootp",
  2849. "rarpboot", "tftpboot" or "diskboot" commands will
  2850. be automatically started (by internally calling
  2851. "bootm")
  2852. If set to "no", a standalone image passed to the
  2853. "bootm" command will be copied to the load address
  2854. (and eventually uncompressed), but NOT be started.
  2855. This can be used to load and uncompress arbitrary
  2856. data.
  2857. fdt_high - if set this restricts the maximum address that the
  2858. flattened device tree will be copied into upon boot.
  2859. For example, if you have a system with 1 GB memory
  2860. at physical address 0x10000000, while Linux kernel
  2861. only recognizes the first 704 MB as low memory, you
  2862. may need to set fdt_high as 0x3C000000 to have the
  2863. device tree blob be copied to the maximum address
  2864. of the 704 MB low memory, so that Linux kernel can
  2865. access it during the boot procedure.
  2866. If this is set to the special value 0xFFFFFFFF then
  2867. the fdt will not be copied at all on boot. For this
  2868. to work it must reside in writable memory, have
  2869. sufficient padding on the end of it for u-boot to
  2870. add the information it needs into it, and the memory
  2871. must be accessible by the kernel.
  2872. fdtcontroladdr- if set this is the address of the control flattened
  2873. device tree used by U-Boot when CONFIG_OF_CONTROL is
  2874. defined.
  2875. i2cfast - (PPC405GP|PPC405EP only)
  2876. if set to 'y' configures Linux I2C driver for fast
  2877. mode (400kHZ). This environment variable is used in
  2878. initialization code. So, for changes to be effective
  2879. it must be saved and board must be reset.
  2880. initrd_high - restrict positioning of initrd images:
  2881. If this variable is not set, initrd images will be
  2882. copied to the highest possible address in RAM; this
  2883. is usually what you want since it allows for
  2884. maximum initrd size. If for some reason you want to
  2885. make sure that the initrd image is loaded below the
  2886. CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
  2887. variable to a value of "no" or "off" or "0".
  2888. Alternatively, you can set it to a maximum upper
  2889. address to use (U-Boot will still check that it
  2890. does not overwrite the U-Boot stack and data).
  2891. For instance, when you have a system with 16 MB
  2892. RAM, and want to reserve 4 MB from use by Linux,
  2893. you can do this by adding "mem=12M" to the value of
  2894. the "bootargs" variable. However, now you must make
  2895. sure that the initrd image is placed in the first
  2896. 12 MB as well - this can be done with
  2897. setenv initrd_high 00c00000
  2898. If you set initrd_high to 0xFFFFFFFF, this is an
  2899. indication to U-Boot that all addresses are legal
  2900. for the Linux kernel, including addresses in flash
  2901. memory. In this case U-Boot will NOT COPY the
  2902. ramdisk at all. This may be useful to reduce the
  2903. boot time on your system, but requires that this
  2904. feature is supported by your Linux kernel.
  2905. ipaddr - IP address; needed for tftpboot command
  2906. loadaddr - Default load address for commands like "bootp",
  2907. "rarpboot", "tftpboot", "loadb" or "diskboot"
  2908. loads_echo - see CONFIG_LOADS_ECHO
  2909. serverip - TFTP server IP address; needed for tftpboot command
  2910. bootretry - see CONFIG_BOOT_RETRY_TIME
  2911. bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
  2912. bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
  2913. ethprime - controls which interface is used first.
  2914. ethact - controls which interface is currently active.
  2915. For example you can do the following
  2916. => setenv ethact FEC
  2917. => ping 192.168.0.1 # traffic sent on FEC
  2918. => setenv ethact SCC
  2919. => ping 10.0.0.1 # traffic sent on SCC
  2920. ethrotate - When set to "no" U-Boot does not go through all
  2921. available network interfaces.
  2922. It just stays at the currently selected interface.
  2923. netretry - When set to "no" each network operation will
  2924. either succeed or fail without retrying.
  2925. When set to "once" the network operation will
  2926. fail when all the available network interfaces
  2927. are tried once without success.
  2928. Useful on scripts which control the retry operation
  2929. themselves.
  2930. npe_ucode - set load address for the NPE microcode
  2931. tftpsrcport - If this is set, the value is used for TFTP's
  2932. UDP source port.
  2933. tftpdstport - If this is set, the value is used for TFTP's UDP
  2934. destination port instead of the Well Know Port 69.
  2935. tftpblocksize - Block size to use for TFTP transfers; if not set,
  2936. we use the TFTP server's default block size
  2937. tftptimeout - Retransmission timeout for TFTP packets (in milli-
  2938. seconds, minimum value is 1000 = 1 second). Defines
  2939. when a packet is considered to be lost so it has to
  2940. be retransmitted. The default is 5000 = 5 seconds.
  2941. Lowering this value may make downloads succeed
  2942. faster in networks with high packet loss rates or
  2943. with unreliable TFTP servers.
  2944. vlan - When set to a value < 4095 the traffic over
  2945. Ethernet is encapsulated/received over 802.1q
  2946. VLAN tagged frames.
  2947. The following image location variables contain the location of images
  2948. used in booting. The "Image" column gives the role of the image and is
  2949. not an environment variable name. The other columns are environment
  2950. variable names. "File Name" gives the name of the file on a TFTP
  2951. server, "RAM Address" gives the location in RAM the image will be
  2952. loaded to, and "Flash Location" gives the image's address in NOR
  2953. flash or offset in NAND flash.
  2954. *Note* - these variables don't have to be defined for all boards, some
  2955. boards currenlty use other variables for these purposes, and some
  2956. boards use these variables for other purposes.
  2957. Image File Name RAM Address Flash Location
  2958. ----- --------- ----------- --------------
  2959. u-boot u-boot u-boot_addr_r u-boot_addr
  2960. Linux kernel bootfile kernel_addr_r kernel_addr
  2961. device tree blob fdtfile fdt_addr_r fdt_addr
  2962. ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
  2963. The following environment variables may be used and automatically
  2964. updated by the network boot commands ("bootp" and "rarpboot"),
  2965. depending the information provided by your boot server:
  2966. bootfile - see above
  2967. dnsip - IP address of your Domain Name Server
  2968. dnsip2 - IP address of your secondary Domain Name Server
  2969. gatewayip - IP address of the Gateway (Router) to use
  2970. hostname - Target hostname
  2971. ipaddr - see above
  2972. netmask - Subnet Mask
  2973. rootpath - Pathname of the root filesystem on the NFS server
  2974. serverip - see above
  2975. There are two special Environment Variables:
  2976. serial# - contains hardware identification information such
  2977. as type string and/or serial number
  2978. ethaddr - Ethernet address
  2979. These variables can be set only once (usually during manufacturing of
  2980. the board). U-Boot refuses to delete or overwrite these variables
  2981. once they have been set once.
  2982. Further special Environment Variables:
  2983. ver - Contains the U-Boot version string as printed
  2984. with the "version" command. This variable is
  2985. readonly (see CONFIG_VERSION_VARIABLE).
  2986. Please note that changes to some configuration parameters may take
  2987. only effect after the next boot (yes, that's just like Windoze :-).
  2988. Command Line Parsing:
  2989. =====================
  2990. There are two different command line parsers available with U-Boot:
  2991. the old "simple" one, and the much more powerful "hush" shell:
  2992. Old, simple command line parser:
  2993. --------------------------------
  2994. - supports environment variables (through setenv / saveenv commands)
  2995. - several commands on one line, separated by ';'
  2996. - variable substitution using "... ${name} ..." syntax
  2997. - special characters ('$', ';') can be escaped by prefixing with '\',
  2998. for example:
  2999. setenv bootcmd bootm \${address}
  3000. - You can also escape text by enclosing in single apostrophes, for example:
  3001. setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
  3002. Hush shell:
  3003. -----------
  3004. - similar to Bourne shell, with control structures like
  3005. if...then...else...fi, for...do...done; while...do...done,
  3006. until...do...done, ...
  3007. - supports environment ("global") variables (through setenv / saveenv
  3008. commands) and local shell variables (through standard shell syntax
  3009. "name=value"); only environment variables can be used with "run"
  3010. command
  3011. General rules:
  3012. --------------
  3013. (1) If a command line (or an environment variable executed by a "run"
  3014. command) contains several commands separated by semicolon, and
  3015. one of these commands fails, then the remaining commands will be
  3016. executed anyway.
  3017. (2) If you execute several variables with one call to run (i. e.
  3018. calling run with a list of variables as arguments), any failing
  3019. command will cause "run" to terminate, i. e. the remaining
  3020. variables are not executed.
  3021. Note for Redundant Ethernet Interfaces:
  3022. =======================================
  3023. Some boards come with redundant Ethernet interfaces; U-Boot supports
  3024. such configurations and is capable of automatic selection of a
  3025. "working" interface when needed. MAC assignment works as follows:
  3026. Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
  3027. MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
  3028. "eth1addr" (=>eth1), "eth2addr", ...
  3029. If the network interface stores some valid MAC address (for instance
  3030. in SROM), this is used as default address if there is NO correspon-
  3031. ding setting in the environment; if the corresponding environment
  3032. variable is set, this overrides the settings in the card; that means:
  3033. o If the SROM has a valid MAC address, and there is no address in the
  3034. environment, the SROM's address is used.
  3035. o If there is no valid address in the SROM, and a definition in the
  3036. environment exists, then the value from the environment variable is
  3037. used.
  3038. o If both the SROM and the environment contain a MAC address, and
  3039. both addresses are the same, this MAC address is used.
  3040. o If both the SROM and the environment contain a MAC address, and the
  3041. addresses differ, the value from the environment is used and a
  3042. warning is printed.
  3043. o If neither SROM nor the environment contain a MAC address, an error
  3044. is raised.
  3045. If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
  3046. will be programmed into hardware as part of the initialization process. This
  3047. may be skipped by setting the appropriate 'ethmacskip' environment variable.
  3048. The naming convention is as follows:
  3049. "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
  3050. Image Formats:
  3051. ==============
  3052. U-Boot is capable of booting (and performing other auxiliary operations on)
  3053. images in two formats:
  3054. New uImage format (FIT)
  3055. -----------------------
  3056. Flexible and powerful format based on Flattened Image Tree -- FIT (similar
  3057. to Flattened Device Tree). It allows the use of images with multiple
  3058. components (several kernels, ramdisks, etc.), with contents protected by
  3059. SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
  3060. Old uImage format
  3061. -----------------
  3062. Old image format is based on binary files which can be basically anything,
  3063. preceded by a special header; see the definitions in include/image.h for
  3064. details; basically, the header defines the following image properties:
  3065. * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
  3066. 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
  3067. LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
  3068. Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
  3069. INTEGRITY).
  3070. * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
  3071. IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
  3072. Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC).
  3073. * Compression Type (uncompressed, gzip, bzip2)
  3074. * Load Address
  3075. * Entry Point
  3076. * Image Name
  3077. * Image Timestamp
  3078. The header is marked by a special Magic Number, and both the header
  3079. and the data portions of the image are secured against corruption by
  3080. CRC32 checksums.
  3081. Linux Support:
  3082. ==============
  3083. Although U-Boot should support any OS or standalone application
  3084. easily, the main focus has always been on Linux during the design of
  3085. U-Boot.
  3086. U-Boot includes many features that so far have been part of some
  3087. special "boot loader" code within the Linux kernel. Also, any
  3088. "initrd" images to be used are no longer part of one big Linux image;
  3089. instead, kernel and "initrd" are separate images. This implementation
  3090. serves several purposes:
  3091. - the same features can be used for other OS or standalone
  3092. applications (for instance: using compressed images to reduce the
  3093. Flash memory footprint)
  3094. - it becomes much easier to port new Linux kernel versions because
  3095. lots of low-level, hardware dependent stuff are done by U-Boot
  3096. - the same Linux kernel image can now be used with different "initrd"
  3097. images; of course this also means that different kernel images can
  3098. be run with the same "initrd". This makes testing easier (you don't
  3099. have to build a new "zImage.initrd" Linux image when you just
  3100. change a file in your "initrd"). Also, a field-upgrade of the
  3101. software is easier now.
  3102. Linux HOWTO:
  3103. ============
  3104. Porting Linux to U-Boot based systems:
  3105. ---------------------------------------
  3106. U-Boot cannot save you from doing all the necessary modifications to
  3107. configure the Linux device drivers for use with your target hardware
  3108. (no, we don't intend to provide a full virtual machine interface to
  3109. Linux :-).
  3110. But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
  3111. Just make sure your machine specific header file (for instance
  3112. include/asm-ppc/tqm8xx.h) includes the same definition of the Board
  3113. Information structure as we define in include/asm-<arch>/u-boot.h,
  3114. and make sure that your definition of IMAP_ADDR uses the same value
  3115. as your U-Boot configuration in CONFIG_SYS_IMMR.
  3116. Configuring the Linux kernel:
  3117. -----------------------------
  3118. No specific requirements for U-Boot. Make sure you have some root
  3119. device (initial ramdisk, NFS) for your target system.
  3120. Building a Linux Image:
  3121. -----------------------
  3122. With U-Boot, "normal" build targets like "zImage" or "bzImage" are
  3123. not used. If you use recent kernel source, a new build target
  3124. "uImage" will exist which automatically builds an image usable by
  3125. U-Boot. Most older kernels also have support for a "pImage" target,
  3126. which was introduced for our predecessor project PPCBoot and uses a
  3127. 100% compatible format.
  3128. Example:
  3129. make TQM850L_config
  3130. make oldconfig
  3131. make dep
  3132. make uImage
  3133. The "uImage" build target uses a special tool (in 'tools/mkimage') to
  3134. encapsulate a compressed Linux kernel image with header information,
  3135. CRC32 checksum etc. for use with U-Boot. This is what we are doing:
  3136. * build a standard "vmlinux" kernel image (in ELF binary format):
  3137. * convert the kernel into a raw binary image:
  3138. ${CROSS_COMPILE}-objcopy -O binary \
  3139. -R .note -R .comment \
  3140. -S vmlinux linux.bin
  3141. * compress the binary image:
  3142. gzip -9 linux.bin
  3143. * package compressed binary image for U-Boot:
  3144. mkimage -A ppc -O linux -T kernel -C gzip \
  3145. -a 0 -e 0 -n "Linux Kernel Image" \
  3146. -d linux.bin.gz uImage
  3147. The "mkimage" tool can also be used to create ramdisk images for use
  3148. with U-Boot, either separated from the Linux kernel image, or
  3149. combined into one file. "mkimage" encapsulates the images with a 64
  3150. byte header containing information about target architecture,
  3151. operating system, image type, compression method, entry points, time
  3152. stamp, CRC32 checksums, etc.
  3153. "mkimage" can be called in two ways: to verify existing images and
  3154. print the header information, or to build new images.
  3155. In the first form (with "-l" option) mkimage lists the information
  3156. contained in the header of an existing U-Boot image; this includes
  3157. checksum verification:
  3158. tools/mkimage -l image
  3159. -l ==> list image header information
  3160. The second form (with "-d" option) is used to build a U-Boot image
  3161. from a "data file" which is used as image payload:
  3162. tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
  3163. -n name -d data_file image
  3164. -A ==> set architecture to 'arch'
  3165. -O ==> set operating system to 'os'
  3166. -T ==> set image type to 'type'
  3167. -C ==> set compression type 'comp'
  3168. -a ==> set load address to 'addr' (hex)
  3169. -e ==> set entry point to 'ep' (hex)
  3170. -n ==> set image name to 'name'
  3171. -d ==> use image data from 'datafile'
  3172. Right now, all Linux kernels for PowerPC systems use the same load
  3173. address (0x00000000), but the entry point address depends on the
  3174. kernel version:
  3175. - 2.2.x kernels have the entry point at 0x0000000C,
  3176. - 2.3.x and later kernels have the entry point at 0x00000000.
  3177. So a typical call to build a U-Boot image would read:
  3178. -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
  3179. > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
  3180. > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
  3181. > examples/uImage.TQM850L
  3182. Image Name: 2.4.4 kernel for TQM850L
  3183. Created: Wed Jul 19 02:34:59 2000
  3184. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  3185. Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
  3186. Load Address: 0x00000000
  3187. Entry Point: 0x00000000
  3188. To verify the contents of the image (or check for corruption):
  3189. -> tools/mkimage -l examples/uImage.TQM850L
  3190. Image Name: 2.4.4 kernel for TQM850L
  3191. Created: Wed Jul 19 02:34:59 2000
  3192. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  3193. Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
  3194. Load Address: 0x00000000
  3195. Entry Point: 0x00000000
  3196. NOTE: for embedded systems where boot time is critical you can trade
  3197. speed for memory and install an UNCOMPRESSED image instead: this
  3198. needs more space in Flash, but boots much faster since it does not
  3199. need to be uncompressed:
  3200. -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
  3201. -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
  3202. > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
  3203. > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
  3204. > examples/uImage.TQM850L-uncompressed
  3205. Image Name: 2.4.4 kernel for TQM850L
  3206. Created: Wed Jul 19 02:34:59 2000
  3207. Image Type: PowerPC Linux Kernel Image (uncompressed)
  3208. Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
  3209. Load Address: 0x00000000
  3210. Entry Point: 0x00000000
  3211. Similar you can build U-Boot images from a 'ramdisk.image.gz' file
  3212. when your kernel is intended to use an initial ramdisk:
  3213. -> tools/mkimage -n 'Simple Ramdisk Image' \
  3214. > -A ppc -O linux -T ramdisk -C gzip \
  3215. > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
  3216. Image Name: Simple Ramdisk Image
  3217. Created: Wed Jan 12 14:01:50 2000
  3218. Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
  3219. Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
  3220. Load Address: 0x00000000
  3221. Entry Point: 0x00000000
  3222. Installing a Linux Image:
  3223. -------------------------
  3224. To downloading a U-Boot image over the serial (console) interface,
  3225. you must convert the image to S-Record format:
  3226. objcopy -I binary -O srec examples/image examples/image.srec
  3227. The 'objcopy' does not understand the information in the U-Boot
  3228. image header, so the resulting S-Record file will be relative to
  3229. address 0x00000000. To load it to a given address, you need to
  3230. specify the target address as 'offset' parameter with the 'loads'
  3231. command.
  3232. Example: install the image to address 0x40100000 (which on the
  3233. TQM8xxL is in the first Flash bank):
  3234. => erase 40100000 401FFFFF
  3235. .......... done
  3236. Erased 8 sectors
  3237. => loads 40100000
  3238. ## Ready for S-Record download ...
  3239. ~>examples/image.srec
  3240. 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
  3241. ...
  3242. 15989 15990 15991 15992
  3243. [file transfer complete]
  3244. [connected]
  3245. ## Start Addr = 0x00000000
  3246. You can check the success of the download using the 'iminfo' command;
  3247. this includes a checksum verification so you can be sure no data
  3248. corruption happened:
  3249. => imi 40100000
  3250. ## Checking Image at 40100000 ...
  3251. Image Name: 2.2.13 for initrd on TQM850L
  3252. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  3253. Data Size: 335725 Bytes = 327 kB = 0 MB
  3254. Load Address: 00000000
  3255. Entry Point: 0000000c
  3256. Verifying Checksum ... OK
  3257. Boot Linux:
  3258. -----------
  3259. The "bootm" command is used to boot an application that is stored in
  3260. memory (RAM or Flash). In case of a Linux kernel image, the contents
  3261. of the "bootargs" environment variable is passed to the kernel as
  3262. parameters. You can check and modify this variable using the
  3263. "printenv" and "setenv" commands:
  3264. => printenv bootargs
  3265. bootargs=root=/dev/ram
  3266. => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
  3267. => printenv bootargs
  3268. bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
  3269. => bootm 40020000
  3270. ## Booting Linux kernel at 40020000 ...
  3271. Image Name: 2.2.13 for NFS on TQM850L
  3272. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  3273. Data Size: 381681 Bytes = 372 kB = 0 MB
  3274. Load Address: 00000000
  3275. Entry Point: 0000000c
  3276. Verifying Checksum ... OK
  3277. Uncompressing Kernel Image ... OK
  3278. 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
  3279. Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
  3280. time_init: decrementer frequency = 187500000/60
  3281. Calibrating delay loop... 49.77 BogoMIPS
  3282. Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
  3283. ...
  3284. If you want to boot a Linux kernel with initial RAM disk, you pass
  3285. the memory addresses of both the kernel and the initrd image (PPBCOOT
  3286. format!) to the "bootm" command:
  3287. => imi 40100000 40200000
  3288. ## Checking Image at 40100000 ...
  3289. Image Name: 2.2.13 for initrd on TQM850L
  3290. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  3291. Data Size: 335725 Bytes = 327 kB = 0 MB
  3292. Load Address: 00000000
  3293. Entry Point: 0000000c
  3294. Verifying Checksum ... OK
  3295. ## Checking Image at 40200000 ...
  3296. Image Name: Simple Ramdisk Image
  3297. Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
  3298. Data Size: 566530 Bytes = 553 kB = 0 MB
  3299. Load Address: 00000000
  3300. Entry Point: 00000000
  3301. Verifying Checksum ... OK
  3302. => bootm 40100000 40200000
  3303. ## Booting Linux kernel at 40100000 ...
  3304. Image Name: 2.2.13 for initrd on TQM850L
  3305. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  3306. Data Size: 335725 Bytes = 327 kB = 0 MB
  3307. Load Address: 00000000
  3308. Entry Point: 0000000c
  3309. Verifying Checksum ... OK
  3310. Uncompressing Kernel Image ... OK
  3311. ## Loading RAMDisk Image at 40200000 ...
  3312. Image Name: Simple Ramdisk Image
  3313. Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
  3314. Data Size: 566530 Bytes = 553 kB = 0 MB
  3315. Load Address: 00000000
  3316. Entry Point: 00000000
  3317. Verifying Checksum ... OK
  3318. Loading Ramdisk ... OK
  3319. 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
  3320. Boot arguments: root=/dev/ram
  3321. time_init: decrementer frequency = 187500000/60
  3322. Calibrating delay loop... 49.77 BogoMIPS
  3323. ...
  3324. RAMDISK: Compressed image found at block 0
  3325. VFS: Mounted root (ext2 filesystem).
  3326. bash#
  3327. Boot Linux and pass a flat device tree:
  3328. -----------
  3329. First, U-Boot must be compiled with the appropriate defines. See the section
  3330. titled "Linux Kernel Interface" above for a more in depth explanation. The
  3331. following is an example of how to start a kernel and pass an updated
  3332. flat device tree:
  3333. => print oftaddr
  3334. oftaddr=0x300000
  3335. => print oft
  3336. oft=oftrees/mpc8540ads.dtb
  3337. => tftp $oftaddr $oft
  3338. Speed: 1000, full duplex
  3339. Using TSEC0 device
  3340. TFTP from server 192.168.1.1; our IP address is 192.168.1.101
  3341. Filename 'oftrees/mpc8540ads.dtb'.
  3342. Load address: 0x300000
  3343. Loading: #
  3344. done
  3345. Bytes transferred = 4106 (100a hex)
  3346. => tftp $loadaddr $bootfile
  3347. Speed: 1000, full duplex
  3348. Using TSEC0 device
  3349. TFTP from server 192.168.1.1; our IP address is 192.168.1.2
  3350. Filename 'uImage'.
  3351. Load address: 0x200000
  3352. Loading:############
  3353. done
  3354. Bytes transferred = 1029407 (fb51f hex)
  3355. => print loadaddr
  3356. loadaddr=200000
  3357. => print oftaddr
  3358. oftaddr=0x300000
  3359. => bootm $loadaddr - $oftaddr
  3360. ## Booting image at 00200000 ...
  3361. Image Name: Linux-2.6.17-dirty
  3362. Image Type: PowerPC Linux Kernel Image (gzip compressed)
  3363. Data Size: 1029343 Bytes = 1005.2 kB
  3364. Load Address: 00000000
  3365. Entry Point: 00000000
  3366. Verifying Checksum ... OK
  3367. Uncompressing Kernel Image ... OK
  3368. Booting using flat device tree at 0x300000
  3369. Using MPC85xx ADS machine description
  3370. Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
  3371. [snip]
  3372. More About U-Boot Image Types:
  3373. ------------------------------
  3374. U-Boot supports the following image types:
  3375. "Standalone Programs" are directly runnable in the environment
  3376. provided by U-Boot; it is expected that (if they behave
  3377. well) you can continue to work in U-Boot after return from
  3378. the Standalone Program.
  3379. "OS Kernel Images" are usually images of some Embedded OS which
  3380. will take over control completely. Usually these programs
  3381. will install their own set of exception handlers, device
  3382. drivers, set up the MMU, etc. - this means, that you cannot
  3383. expect to re-enter U-Boot except by resetting the CPU.
  3384. "RAMDisk Images" are more or less just data blocks, and their
  3385. parameters (address, size) are passed to an OS kernel that is
  3386. being started.
  3387. "Multi-File Images" contain several images, typically an OS
  3388. (Linux) kernel image and one or more data images like
  3389. RAMDisks. This construct is useful for instance when you want
  3390. to boot over the network using BOOTP etc., where the boot
  3391. server provides just a single image file, but you want to get
  3392. for instance an OS kernel and a RAMDisk image.
  3393. "Multi-File Images" start with a list of image sizes, each
  3394. image size (in bytes) specified by an "uint32_t" in network
  3395. byte order. This list is terminated by an "(uint32_t)0".
  3396. Immediately after the terminating 0 follow the images, one by
  3397. one, all aligned on "uint32_t" boundaries (size rounded up to
  3398. a multiple of 4 bytes).
  3399. "Firmware Images" are binary images containing firmware (like
  3400. U-Boot or FPGA images) which usually will be programmed to
  3401. flash memory.
  3402. "Script files" are command sequences that will be executed by
  3403. U-Boot's command interpreter; this feature is especially
  3404. useful when you configure U-Boot to use a real shell (hush)
  3405. as command interpreter.
  3406. Standalone HOWTO:
  3407. =================
  3408. One of the features of U-Boot is that you can dynamically load and
  3409. run "standalone" applications, which can use some resources of
  3410. U-Boot like console I/O functions or interrupt services.
  3411. Two simple examples are included with the sources:
  3412. "Hello World" Demo:
  3413. -------------------
  3414. 'examples/hello_world.c' contains a small "Hello World" Demo
  3415. application; it is automatically compiled when you build U-Boot.
  3416. It's configured to run at address 0x00040004, so you can play with it
  3417. like that:
  3418. => loads
  3419. ## Ready for S-Record download ...
  3420. ~>examples/hello_world.srec
  3421. 1 2 3 4 5 6 7 8 9 10 11 ...
  3422. [file transfer complete]
  3423. [connected]
  3424. ## Start Addr = 0x00040004
  3425. => go 40004 Hello World! This is a test.
  3426. ## Starting application at 0x00040004 ...
  3427. Hello World
  3428. argc = 7
  3429. argv[0] = "40004"
  3430. argv[1] = "Hello"
  3431. argv[2] = "World!"
  3432. argv[3] = "This"
  3433. argv[4] = "is"
  3434. argv[5] = "a"
  3435. argv[6] = "test."
  3436. argv[7] = "<NULL>"
  3437. Hit any key to exit ...
  3438. ## Application terminated, rc = 0x0
  3439. Another example, which demonstrates how to register a CPM interrupt
  3440. handler with the U-Boot code, can be found in 'examples/timer.c'.
  3441. Here, a CPM timer is set up to generate an interrupt every second.
  3442. The interrupt service routine is trivial, just printing a '.'
  3443. character, but this is just a demo program. The application can be
  3444. controlled by the following keys:
  3445. ? - print current values og the CPM Timer registers
  3446. b - enable interrupts and start timer
  3447. e - stop timer and disable interrupts
  3448. q - quit application
  3449. => loads
  3450. ## Ready for S-Record download ...
  3451. ~>examples/timer.srec
  3452. 1 2 3 4 5 6 7 8 9 10 11 ...
  3453. [file transfer complete]
  3454. [connected]
  3455. ## Start Addr = 0x00040004
  3456. => go 40004
  3457. ## Starting application at 0x00040004 ...
  3458. TIMERS=0xfff00980
  3459. Using timer 1
  3460. tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
  3461. Hit 'b':
  3462. [q, b, e, ?] Set interval 1000000 us
  3463. Enabling timer
  3464. Hit '?':
  3465. [q, b, e, ?] ........
  3466. tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
  3467. Hit '?':
  3468. [q, b, e, ?] .
  3469. tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
  3470. Hit '?':
  3471. [q, b, e, ?] .
  3472. tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
  3473. Hit '?':
  3474. [q, b, e, ?] .
  3475. tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
  3476. Hit 'e':
  3477. [q, b, e, ?] ...Stopping timer
  3478. Hit 'q':
  3479. [q, b, e, ?] ## Application terminated, rc = 0x0
  3480. Minicom warning:
  3481. ================
  3482. Over time, many people have reported problems when trying to use the
  3483. "minicom" terminal emulation program for serial download. I (wd)
  3484. consider minicom to be broken, and recommend not to use it. Under
  3485. Unix, I recommend to use C-Kermit for general purpose use (and
  3486. especially for kermit binary protocol download ("loadb" command), and
  3487. use "cu" for S-Record download ("loads" command).
  3488. Nevertheless, if you absolutely want to use it try adding this
  3489. configuration to your "File transfer protocols" section:
  3490. Name Program Name U/D FullScr IO-Red. Multi
  3491. X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
  3492. Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
  3493. NetBSD Notes:
  3494. =============
  3495. Starting at version 0.9.2, U-Boot supports NetBSD both as host
  3496. (build U-Boot) and target system (boots NetBSD/mpc8xx).
  3497. Building requires a cross environment; it is known to work on
  3498. NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
  3499. need gmake since the Makefiles are not compatible with BSD make).
  3500. Note that the cross-powerpc package does not install include files;
  3501. attempting to build U-Boot will fail because <machine/ansi.h> is
  3502. missing. This file has to be installed and patched manually:
  3503. # cd /usr/pkg/cross/powerpc-netbsd/include
  3504. # mkdir powerpc
  3505. # ln -s powerpc machine
  3506. # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
  3507. # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
  3508. Native builds *don't* work due to incompatibilities between native
  3509. and U-Boot include files.
  3510. Booting assumes that (the first part of) the image booted is a
  3511. stage-2 loader which in turn loads and then invokes the kernel
  3512. proper. Loader sources will eventually appear in the NetBSD source
  3513. tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
  3514. meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
  3515. Implementation Internals:
  3516. =========================
  3517. The following is not intended to be a complete description of every
  3518. implementation detail. However, it should help to understand the
  3519. inner workings of U-Boot and make it easier to port it to custom
  3520. hardware.
  3521. Initial Stack, Global Data:
  3522. ---------------------------
  3523. The implementation of U-Boot is complicated by the fact that U-Boot
  3524. starts running out of ROM (flash memory), usually without access to
  3525. system RAM (because the memory controller is not initialized yet).
  3526. This means that we don't have writable Data or BSS segments, and BSS
  3527. is not initialized as zero. To be able to get a C environment working
  3528. at all, we have to allocate at least a minimal stack. Implementation
  3529. options for this are defined and restricted by the CPU used: Some CPU
  3530. models provide on-chip memory (like the IMMR area on MPC8xx and
  3531. MPC826x processors), on others (parts of) the data cache can be
  3532. locked as (mis-) used as memory, etc.
  3533. Chris Hallinan posted a good summary of these issues to the
  3534. U-Boot mailing list:
  3535. Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
  3536. From: "Chris Hallinan" <clh@net1plus.com>
  3537. Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
  3538. ...
  3539. Correct me if I'm wrong, folks, but the way I understand it
  3540. is this: Using DCACHE as initial RAM for Stack, etc, does not
  3541. require any physical RAM backing up the cache. The cleverness
  3542. is that the cache is being used as a temporary supply of
  3543. necessary storage before the SDRAM controller is setup. It's
  3544. beyond the scope of this list to explain the details, but you
  3545. can see how this works by studying the cache architecture and
  3546. operation in the architecture and processor-specific manuals.
  3547. OCM is On Chip Memory, which I believe the 405GP has 4K. It
  3548. is another option for the system designer to use as an
  3549. initial stack/RAM area prior to SDRAM being available. Either
  3550. option should work for you. Using CS 4 should be fine if your
  3551. board designers haven't used it for something that would
  3552. cause you grief during the initial boot! It is frequently not
  3553. used.
  3554. CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
  3555. with your processor/board/system design. The default value
  3556. you will find in any recent u-boot distribution in
  3557. walnut.h should work for you. I'd set it to a value larger
  3558. than your SDRAM module. If you have a 64MB SDRAM module, set
  3559. it above 400_0000. Just make sure your board has no resources
  3560. that are supposed to respond to that address! That code in
  3561. start.S has been around a while and should work as is when
  3562. you get the config right.
  3563. -Chris Hallinan
  3564. DS4.COM, Inc.
  3565. It is essential to remember this, since it has some impact on the C
  3566. code for the initialization procedures:
  3567. * Initialized global data (data segment) is read-only. Do not attempt
  3568. to write it.
  3569. * Do not use any uninitialized global data (or implicitely initialized
  3570. as zero data - BSS segment) at all - this is undefined, initiali-
  3571. zation is performed later (when relocating to RAM).
  3572. * Stack space is very limited. Avoid big data buffers or things like
  3573. that.
  3574. Having only the stack as writable memory limits means we cannot use
  3575. normal global data to share information beween the code. But it
  3576. turned out that the implementation of U-Boot can be greatly
  3577. simplified by making a global data structure (gd_t) available to all
  3578. functions. We could pass a pointer to this data as argument to _all_
  3579. functions, but this would bloat the code. Instead we use a feature of
  3580. the GCC compiler (Global Register Variables) to share the data: we
  3581. place a pointer (gd) to the global data into a register which we
  3582. reserve for this purpose.
  3583. When choosing a register for such a purpose we are restricted by the
  3584. relevant (E)ABI specifications for the current architecture, and by
  3585. GCC's implementation.
  3586. For PowerPC, the following registers have specific use:
  3587. R1: stack pointer
  3588. R2: reserved for system use
  3589. R3-R4: parameter passing and return values
  3590. R5-R10: parameter passing
  3591. R13: small data area pointer
  3592. R30: GOT pointer
  3593. R31: frame pointer
  3594. (U-Boot also uses R12 as internal GOT pointer. r12
  3595. is a volatile register so r12 needs to be reset when
  3596. going back and forth between asm and C)
  3597. ==> U-Boot will use R2 to hold a pointer to the global data
  3598. Note: on PPC, we could use a static initializer (since the
  3599. address of the global data structure is known at compile time),
  3600. but it turned out that reserving a register results in somewhat
  3601. smaller code - although the code savings are not that big (on
  3602. average for all boards 752 bytes for the whole U-Boot image,
  3603. 624 text + 127 data).
  3604. On Blackfin, the normal C ABI (except for P3) is followed as documented here:
  3605. http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
  3606. ==> U-Boot will use P3 to hold a pointer to the global data
  3607. On ARM, the following registers are used:
  3608. R0: function argument word/integer result
  3609. R1-R3: function argument word
  3610. R9: GOT pointer
  3611. R10: stack limit (used only if stack checking if enabled)
  3612. R11: argument (frame) pointer
  3613. R12: temporary workspace
  3614. R13: stack pointer
  3615. R14: link register
  3616. R15: program counter
  3617. ==> U-Boot will use R8 to hold a pointer to the global data
  3618. On Nios II, the ABI is documented here:
  3619. http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
  3620. ==> U-Boot will use gp to hold a pointer to the global data
  3621. Note: on Nios II, we give "-G0" option to gcc and don't use gp
  3622. to access small data sections, so gp is free.
  3623. On NDS32, the following registers are used:
  3624. R0-R1: argument/return
  3625. R2-R5: argument
  3626. R15: temporary register for assembler
  3627. R16: trampoline register
  3628. R28: frame pointer (FP)
  3629. R29: global pointer (GP)
  3630. R30: link register (LP)
  3631. R31: stack pointer (SP)
  3632. PC: program counter (PC)
  3633. ==> U-Boot will use R10 to hold a pointer to the global data
  3634. NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
  3635. or current versions of GCC may "optimize" the code too much.
  3636. Memory Management:
  3637. ------------------
  3638. U-Boot runs in system state and uses physical addresses, i.e. the
  3639. MMU is not used either for address mapping nor for memory protection.
  3640. The available memory is mapped to fixed addresses using the memory
  3641. controller. In this process, a contiguous block is formed for each
  3642. memory type (Flash, SDRAM, SRAM), even when it consists of several
  3643. physical memory banks.
  3644. U-Boot is installed in the first 128 kB of the first Flash bank (on
  3645. TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
  3646. booting and sizing and initializing DRAM, the code relocates itself
  3647. to the upper end of DRAM. Immediately below the U-Boot code some
  3648. memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
  3649. configuration setting]. Below that, a structure with global Board
  3650. Info data is placed, followed by the stack (growing downward).
  3651. Additionally, some exception handler code is copied to the low 8 kB
  3652. of DRAM (0x00000000 ... 0x00001FFF).
  3653. So a typical memory configuration with 16 MB of DRAM could look like
  3654. this:
  3655. 0x0000 0000 Exception Vector code
  3656. :
  3657. 0x0000 1FFF
  3658. 0x0000 2000 Free for Application Use
  3659. :
  3660. :
  3661. :
  3662. :
  3663. 0x00FB FF20 Monitor Stack (Growing downward)
  3664. 0x00FB FFAC Board Info Data and permanent copy of global data
  3665. 0x00FC 0000 Malloc Arena
  3666. :
  3667. 0x00FD FFFF
  3668. 0x00FE 0000 RAM Copy of Monitor Code
  3669. ... eventually: LCD or video framebuffer
  3670. ... eventually: pRAM (Protected RAM - unchanged by reset)
  3671. 0x00FF FFFF [End of RAM]
  3672. System Initialization:
  3673. ----------------------
  3674. In the reset configuration, U-Boot starts at the reset entry point
  3675. (on most PowerPC systems at address 0x00000100). Because of the reset
  3676. configuration for CS0# this is a mirror of the onboard Flash memory.
  3677. To be able to re-map memory U-Boot then jumps to its link address.
  3678. To be able to implement the initialization code in C, a (small!)
  3679. initial stack is set up in the internal Dual Ported RAM (in case CPUs
  3680. which provide such a feature like MPC8xx or MPC8260), or in a locked
  3681. part of the data cache. After that, U-Boot initializes the CPU core,
  3682. the caches and the SIU.
  3683. Next, all (potentially) available memory banks are mapped using a
  3684. preliminary mapping. For example, we put them on 512 MB boundaries
  3685. (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
  3686. on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
  3687. programmed for SDRAM access. Using the temporary configuration, a
  3688. simple memory test is run that determines the size of the SDRAM
  3689. banks.
  3690. When there is more than one SDRAM bank, and the banks are of
  3691. different size, the largest is mapped first. For equal size, the first
  3692. bank (CS2#) is mapped first. The first mapping is always for address
  3693. 0x00000000, with any additional banks following immediately to create
  3694. contiguous memory starting from 0.
  3695. Then, the monitor installs itself at the upper end of the SDRAM area
  3696. and allocates memory for use by malloc() and for the global Board
  3697. Info data; also, the exception vector code is copied to the low RAM
  3698. pages, and the final stack is set up.
  3699. Only after this relocation will you have a "normal" C environment;
  3700. until that you are restricted in several ways, mostly because you are
  3701. running from ROM, and because the code will have to be relocated to a
  3702. new address in RAM.
  3703. U-Boot Porting Guide:
  3704. ----------------------
  3705. [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
  3706. list, October 2002]
  3707. int main(int argc, char *argv[])
  3708. {
  3709. sighandler_t no_more_time;
  3710. signal(SIGALRM, no_more_time);
  3711. alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
  3712. if (available_money > available_manpower) {
  3713. Pay consultant to port U-Boot;
  3714. return 0;
  3715. }
  3716. Download latest U-Boot source;
  3717. Subscribe to u-boot mailing list;
  3718. if (clueless)
  3719. email("Hi, I am new to U-Boot, how do I get started?");
  3720. while (learning) {
  3721. Read the README file in the top level directory;
  3722. Read http://www.denx.de/twiki/bin/view/DULG/Manual;
  3723. Read applicable doc/*.README;
  3724. Read the source, Luke;
  3725. /* find . -name "*.[chS]" | xargs grep -i <keyword> */
  3726. }
  3727. if (available_money > toLocalCurrency ($2500))
  3728. Buy a BDI3000;
  3729. else
  3730. Add a lot of aggravation and time;
  3731. if (a similar board exists) { /* hopefully... */
  3732. cp -a board/<similar> board/<myboard>
  3733. cp include/configs/<similar>.h include/configs/<myboard>.h
  3734. } else {
  3735. Create your own board support subdirectory;
  3736. Create your own board include/configs/<myboard>.h file;
  3737. }
  3738. Edit new board/<myboard> files
  3739. Edit new include/configs/<myboard>.h
  3740. while (!accepted) {
  3741. while (!running) {
  3742. do {
  3743. Add / modify source code;
  3744. } until (compiles);
  3745. Debug;
  3746. if (clueless)
  3747. email("Hi, I am having problems...");
  3748. }
  3749. Send patch file to the U-Boot email list;
  3750. if (reasonable critiques)
  3751. Incorporate improvements from email list code review;
  3752. else
  3753. Defend code as written;
  3754. }
  3755. return 0;
  3756. }
  3757. void no_more_time (int sig)
  3758. {
  3759. hire_a_guru();
  3760. }
  3761. Coding Standards:
  3762. -----------------
  3763. All contributions to U-Boot should conform to the Linux kernel
  3764. coding style; see the file "Documentation/CodingStyle" and the script
  3765. "scripts/Lindent" in your Linux kernel source directory.
  3766. Source files originating from a different project (for example the
  3767. MTD subsystem) are generally exempt from these guidelines and are not
  3768. reformated to ease subsequent migration to newer versions of those
  3769. sources.
  3770. Please note that U-Boot is implemented in C (and to some small parts in
  3771. Assembler); no C++ is used, so please do not use C++ style comments (//)
  3772. in your code.
  3773. Please also stick to the following formatting rules:
  3774. - remove any trailing white space
  3775. - use TAB characters for indentation and vertical alignment, not spaces
  3776. - make sure NOT to use DOS '\r\n' line feeds
  3777. - do not add more than 2 consecutive empty lines to source files
  3778. - do not add trailing empty lines to source files
  3779. Submissions which do not conform to the standards may be returned
  3780. with a request to reformat the changes.
  3781. Submitting Patches:
  3782. -------------------
  3783. Since the number of patches for U-Boot is growing, we need to
  3784. establish some rules. Submissions which do not conform to these rules
  3785. may be rejected, even when they contain important and valuable stuff.
  3786. Please see http://www.denx.de/wiki/U-Boot/Patches for details.
  3787. Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
  3788. see http://lists.denx.de/mailman/listinfo/u-boot
  3789. When you send a patch, please include the following information with
  3790. it:
  3791. * For bug fixes: a description of the bug and how your patch fixes
  3792. this bug. Please try to include a way of demonstrating that the
  3793. patch actually fixes something.
  3794. * For new features: a description of the feature and your
  3795. implementation.
  3796. * A CHANGELOG entry as plaintext (separate from the patch)
  3797. * For major contributions, your entry to the CREDITS file
  3798. * When you add support for a new board, don't forget to add this
  3799. board to the MAINTAINERS file, too.
  3800. * If your patch adds new configuration options, don't forget to
  3801. document these in the README file.
  3802. * The patch itself. If you are using git (which is *strongly*
  3803. recommended) you can easily generate the patch using the
  3804. "git format-patch". If you then use "git send-email" to send it to
  3805. the U-Boot mailing list, you will avoid most of the common problems
  3806. with some other mail clients.
  3807. If you cannot use git, use "diff -purN OLD NEW". If your version of
  3808. diff does not support these options, then get the latest version of
  3809. GNU diff.
  3810. The current directory when running this command shall be the parent
  3811. directory of the U-Boot source tree (i. e. please make sure that
  3812. your patch includes sufficient directory information for the
  3813. affected files).
  3814. We prefer patches as plain text. MIME attachments are discouraged,
  3815. and compressed attachments must not be used.
  3816. * If one logical set of modifications affects or creates several
  3817. files, all these changes shall be submitted in a SINGLE patch file.
  3818. * Changesets that contain different, unrelated modifications shall be
  3819. submitted as SEPARATE patches, one patch per changeset.
  3820. Notes:
  3821. * Before sending the patch, run the MAKEALL script on your patched
  3822. source tree and make sure that no errors or warnings are reported
  3823. for any of the boards.
  3824. * Keep your modifications to the necessary minimum: A patch
  3825. containing several unrelated changes or arbitrary reformats will be
  3826. returned with a request to re-formatting / split it.
  3827. * If you modify existing code, make sure that your new code does not
  3828. add to the memory footprint of the code ;-) Small is beautiful!
  3829. When adding new features, these should compile conditionally only
  3830. (using #ifdef), and the resulting code with the new feature
  3831. disabled must not need more memory than the old code without your
  3832. modification.
  3833. * Remember that there is a size limit of 100 kB per message on the
  3834. u-boot mailing list. Bigger patches will be moderated. If they are
  3835. reasonable and not too big, they will be acknowledged. But patches
  3836. bigger than the size limit should be avoided.