2 # (C) Copyright 2000 - 2011
3 # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5 # See file CREDITS for list of people who contributed to this
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.
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.
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,
27 This directory contains the source code for U-Boot, a boot loader for
28 Embedded boards based on PowerPC, ARM, MIPS and several other
29 processors, which can be installed in a boot ROM and used to
30 initialize and test the hardware or to download and run application
33 The development of U-Boot is closely related to Linux: some parts of
34 the source code originate in the Linux source tree, we have some
35 header files in common, and special provision has been made to
36 support booting of Linux images.
38 Some attention has been paid to make this software easily
39 configurable and extendable. For instance, all monitor commands are
40 implemented with the same call interface, so that it's very easy to
41 add new commands. Also, instead of permanently adding rarely used
42 code (for instance hardware test utilities) to the monitor, you can
43 load and run it dynamically.
49 In general, all boards for which a configuration option exists in the
50 Makefile have been tested to some extent and can be considered
51 "working". In fact, many of them are used in production systems.
53 In case of problems see the CHANGELOG and CREDITS files to find out
54 who contributed the specific port. The MAINTAINERS file lists board
61 In case you have questions about, problems with or contributions for
62 U-Boot you should send a message to the U-Boot mailing list at
63 <u-boot@lists.denx.de>. There is also an archive of previous traffic
64 on the mailing list - please search the archive before asking FAQ's.
65 Please see http://lists.denx.de/pipermail/u-boot and
66 http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
69 Where to get source code:
70 =========================
72 The U-Boot source code is maintained in the git repository at
73 git://www.denx.de/git/u-boot.git ; you can browse it online at
74 http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
76 The "snapshot" links on this page allow you to download tarballs of
77 any version you might be interested in. Official releases are also
78 available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
81 Pre-built (and tested) images are available from
82 ftp://ftp.denx.de/pub/u-boot/images/
88 - start from 8xxrom sources
89 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
91 - make it easier to add custom boards
92 - make it possible to add other [PowerPC] CPUs
93 - extend functions, especially:
94 * Provide extended interface to Linux boot loader
97 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
98 - create ARMBoot project (http://sourceforge.net/projects/armboot)
99 - add other CPU families (starting with ARM)
100 - create U-Boot project (http://sourceforge.net/projects/u-boot)
101 - current project page: see http://www.denx.de/wiki/U-Boot
107 The "official" name of this project is "Das U-Boot". The spelling
108 "U-Boot" shall be used in all written text (documentation, comments
109 in source files etc.). Example:
111 This is the README file for the U-Boot project.
113 File names etc. shall be based on the string "u-boot". Examples:
115 include/asm-ppc/u-boot.h
117 #include <asm/u-boot.h>
119 Variable names, preprocessor constants etc. shall be either based on
120 the string "u_boot" or on "U_BOOT". Example:
122 U_BOOT_VERSION u_boot_logo
123 IH_OS_U_BOOT u_boot_hush_start
129 Starting with the release in October 2008, the names of the releases
130 were changed from numerical release numbers without deeper meaning
131 into a time stamp based numbering. Regular releases are identified by
132 names consisting of the calendar year and month of the release date.
133 Additional fields (if present) indicate release candidates or bug fix
134 releases in "stable" maintenance trees.
137 U-Boot v2009.11 - Release November 2009
138 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
139 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release
145 /arch Architecture specific files
146 /arm Files generic to ARM architecture
147 /cpu CPU specific files
148 /arm720t Files specific to ARM 720 CPUs
149 /arm920t Files specific to ARM 920 CPUs
150 /at91rm9200 Files specific to Atmel AT91RM9200 CPU
151 /imx Files specific to Freescale MC9328 i.MX CPUs
152 /s3c24x0 Files specific to Samsung S3C24X0 CPUs
153 /arm925t Files specific to ARM 925 CPUs
154 /arm926ejs Files specific to ARM 926 CPUs
155 /arm1136 Files specific to ARM 1136 CPUs
156 /ixp Files specific to Intel XScale IXP CPUs
157 /pxa Files specific to Intel XScale PXA CPUs
158 /s3c44b0 Files specific to Samsung S3C44B0 CPUs
159 /sa1100 Files specific to Intel StrongARM SA1100 CPUs
160 /lib Architecture specific library files
161 /avr32 Files generic to AVR32 architecture
162 /cpu CPU specific files
163 /lib Architecture specific library files
164 /blackfin Files generic to Analog Devices Blackfin architecture
165 /cpu CPU specific files
166 /lib Architecture specific library files
167 /x86 Files generic to x86 architecture
168 /cpu CPU specific files
169 /lib Architecture specific library files
170 /m68k Files generic to m68k architecture
171 /cpu CPU specific files
172 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
173 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
174 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
175 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
176 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
177 /lib Architecture specific library files
178 /microblaze Files generic to microblaze architecture
179 /cpu CPU specific files
180 /lib Architecture specific library files
181 /mips Files generic to MIPS architecture
182 /cpu CPU specific files
183 /lib Architecture specific library files
184 /nios2 Files generic to Altera NIOS2 architecture
185 /cpu CPU specific files
186 /lib Architecture specific library files
187 /powerpc Files generic to PowerPC architecture
188 /cpu CPU specific files
189 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
190 /mpc5xx Files specific to Freescale MPC5xx CPUs
191 /mpc5xxx Files specific to Freescale MPC5xxx CPUs
192 /mpc8xx Files specific to Freescale MPC8xx CPUs
193 /mpc8220 Files specific to Freescale MPC8220 CPUs
194 /mpc824x Files specific to Freescale MPC824x CPUs
195 /mpc8260 Files specific to Freescale MPC8260 CPUs
196 /mpc85xx Files specific to Freescale MPC85xx CPUs
197 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
198 /lib Architecture specific library files
199 /sh Files generic to SH architecture
200 /cpu CPU specific files
201 /sh2 Files specific to sh2 CPUs
202 /sh3 Files specific to sh3 CPUs
203 /sh4 Files specific to sh4 CPUs
204 /lib Architecture specific library files
205 /sparc Files generic to SPARC architecture
206 /cpu CPU specific files
207 /leon2 Files specific to Gaisler LEON2 SPARC CPU
208 /leon3 Files specific to Gaisler LEON3 SPARC CPU
209 /lib Architecture specific library files
210 /api Machine/arch independent API for external apps
211 /board Board dependent files
212 /common Misc architecture independent functions
213 /disk Code for disk drive partition handling
214 /doc Documentation (don't expect too much)
215 /drivers Commonly used device drivers
216 /examples Example code for standalone applications, etc.
217 /fs Filesystem code (cramfs, ext2, jffs2, etc.)
218 /include Header Files
219 /lib Files generic to all architectures
220 /libfdt Library files to support flattened device trees
221 /lzma Library files to support LZMA decompression
222 /lzo Library files to support LZO decompression
224 /post Power On Self Test
225 /rtc Real Time Clock drivers
226 /tools Tools to build S-Record or U-Boot images, etc.
228 Software Configuration:
229 =======================
231 Configuration is usually done using C preprocessor defines; the
232 rationale behind that is to avoid dead code whenever possible.
234 There are two classes of configuration variables:
236 * Configuration _OPTIONS_:
237 These are selectable by the user and have names beginning with
240 * Configuration _SETTINGS_:
241 These depend on the hardware etc. and should not be meddled with if
242 you don't know what you're doing; they have names beginning with
245 Later we will add a configuration tool - probably similar to or even
246 identical to what's used for the Linux kernel. Right now, we have to
247 do the configuration by hand, which means creating some symbolic
248 links and editing some configuration files. We use the TQM8xxL boards
252 Selection of Processor Architecture and Board Type:
253 ---------------------------------------------------
255 For all supported boards there are ready-to-use default
256 configurations available; just type "make <board_name>_config".
258 Example: For a TQM823L module type:
263 For the Cogent platform, you need to specify the CPU type as well;
264 e.g. "make cogent_mpc8xx_config". And also configure the cogent
265 directory according to the instructions in cogent/README.
268 Configuration Options:
269 ----------------------
271 Configuration depends on the combination of board and CPU type; all
272 such information is kept in a configuration file
273 "include/configs/<board_name>.h".
275 Example: For a TQM823L module, all configuration settings are in
276 "include/configs/TQM823L.h".
279 Many of the options are named exactly as the corresponding Linux
280 kernel configuration options. The intention is to make it easier to
281 build a config tool - later.
284 The following options need to be configured:
286 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
288 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
290 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
291 Define exactly one, e.g. CONFIG_ATSTK1002
293 - CPU Module Type: (if CONFIG_COGENT is defined)
294 Define exactly one of
296 --- FIXME --- not tested yet:
297 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
298 CONFIG_CMA287_23, CONFIG_CMA287_50
300 - Motherboard Type: (if CONFIG_COGENT is defined)
301 Define exactly one of
302 CONFIG_CMA101, CONFIG_CMA102
304 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
305 Define one or more of
308 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
309 Define one or more of
310 CONFIG_LCD_HEARTBEAT - update a character position on
311 the LCD display every second with
314 - Board flavour: (if CONFIG_MPC8260ADS is defined)
317 CONFIG_SYS_8260ADS - original MPC8260ADS
318 CONFIG_SYS_8266ADS - MPC8266ADS
319 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
320 CONFIG_SYS_8272ADS - MPC8272ADS
322 - Marvell Family Member
323 CONFIG_SYS_MVFS - define it if you want to enable
324 multiple fs option at one time
325 for marvell soc family
327 - MPC824X Family Member (if CONFIG_MPC824X is defined)
328 Define exactly one of
329 CONFIG_MPC8240, CONFIG_MPC8245
331 - 8xx CPU Options: (if using an MPC8xx CPU)
332 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
333 get_gclk_freq() cannot work
334 e.g. if there is no 32KHz
335 reference PIT/RTC clock
336 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
339 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
340 CONFIG_SYS_8xx_CPUCLK_MIN
341 CONFIG_SYS_8xx_CPUCLK_MAX
342 CONFIG_8xx_CPUCLK_DEFAULT
343 See doc/README.MPC866
345 CONFIG_SYS_MEASURE_CPUCLK
347 Define this to measure the actual CPU clock instead
348 of relying on the correctness of the configured
349 values. Mostly useful for board bringup to make sure
350 the PLL is locked at the intended frequency. Note
351 that this requires a (stable) reference clock (32 kHz
352 RTC clock or CONFIG_SYS_8XX_XIN)
354 CONFIG_SYS_DELAYED_ICACHE
356 Define this option if you want to enable the
357 ICache only when Code runs from RAM.
360 CONFIG_SYS_FSL_TBCLK_DIV
362 Defines the core time base clock divider ratio compared to the
363 system clock. On most PQ3 devices this is 8, on newer QorIQ
364 devices it can be 16 or 32. The ratio varies from SoC to Soc.
366 CONFIG_SYS_FSL_PCIE_COMPAT
368 Defines the string to utilize when trying to match PCIe device
369 tree nodes for the given platform.
371 - Intel Monahans options:
372 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
374 Defines the Monahans run mode to oscillator
375 ratio. Valid values are 8, 16, 24, 31. The core
376 frequency is this value multiplied by 13 MHz.
378 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
380 Defines the Monahans turbo mode to oscillator
381 ratio. Valid values are 1 (default if undefined) and
382 2. The core frequency as calculated above is multiplied
385 - Linux Kernel Interface:
388 U-Boot stores all clock information in Hz
389 internally. For binary compatibility with older Linux
390 kernels (which expect the clocks passed in the
391 bd_info data to be in MHz) the environment variable
392 "clocks_in_mhz" can be defined so that U-Boot
393 converts clock data to MHZ before passing it to the
395 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
396 "clocks_in_mhz=1" is automatically included in the
399 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
401 When transferring memsize parameter to linux, some versions
402 expect it to be in bytes, others in MB.
403 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
407 New kernel versions are expecting firmware settings to be
408 passed using flattened device trees (based on open firmware
412 * New libfdt-based support
413 * Adds the "fdt" command
414 * The bootm command automatically updates the fdt
416 OF_CPU - The proper name of the cpus node (only required for
417 MPC512X and MPC5xxx based boards).
418 OF_SOC - The proper name of the soc node (only required for
419 MPC512X and MPC5xxx based boards).
420 OF_TBCLK - The timebase frequency.
421 OF_STDOUT_PATH - The path to the console device
423 boards with QUICC Engines require OF_QE to set UCC MAC
426 CONFIG_OF_BOARD_SETUP
428 Board code has addition modification that it wants to make
429 to the flat device tree before handing it off to the kernel
433 This define fills in the correct boot CPU in the boot
434 param header, the default value is zero if undefined.
438 U-Boot can detect if an IDE device is present or not.
439 If not, and this new config option is activated, U-Boot
440 removes the ATA node from the DTS before booting Linux,
441 so the Linux IDE driver does not probe the device and
442 crash. This is needed for buggy hardware (uc101) where
443 no pull down resistor is connected to the signal IDE5V_DD7.
445 - vxWorks boot parameters:
447 bootvx constructs a valid bootline using the following
448 environments variables: bootfile, ipaddr, serverip, hostname.
449 It loads the vxWorks image pointed bootfile.
451 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
452 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
453 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
454 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
456 CONFIG_SYS_VXWORKS_ADD_PARAMS
458 Add it at the end of the bootline. E.g "u=username pw=secret"
460 Note: If a "bootargs" environment is defined, it will overwride
461 the defaults discussed just above.
463 - Cache Configuration:
464 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
465 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
466 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
471 Define this if you want support for Amba PrimeCell PL010 UARTs.
475 Define this if you want support for Amba PrimeCell PL011 UARTs.
479 If you have Amba PrimeCell PL011 UARTs, set this variable to
480 the clock speed of the UARTs.
484 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
485 define this to a list of base addresses for each (supported)
486 port. See e.g. include/configs/versatile.h
488 CONFIG_PL011_SERIAL_RLCR
490 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
491 have separate receive and transmit line control registers. Set
492 this variable to initialize the extra register.
494 CONFIG_PL011_SERIAL_FLUSH_ON_INIT
496 On some platforms (e.g. U8500) U-Boot is loaded by a second stage
497 boot loader that has already initialized the UART. Define this
498 variable to flush the UART at init time.
502 Depending on board, define exactly one serial port
503 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
504 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
505 console by defining CONFIG_8xx_CONS_NONE
507 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
508 port routines must be defined elsewhere
509 (i.e. serial_init(), serial_getc(), ...)
512 Enables console device for a color framebuffer. Needs following
513 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
514 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
516 VIDEO_HW_RECTFILL graphic chip supports
519 VIDEO_HW_BITBLT graphic chip supports
520 bit-blit (cf. smiLynxEM)
521 VIDEO_VISIBLE_COLS visible pixel columns
523 VIDEO_VISIBLE_ROWS visible pixel rows
524 VIDEO_PIXEL_SIZE bytes per pixel
525 VIDEO_DATA_FORMAT graphic data format
526 (0-5, cf. cfb_console.c)
527 VIDEO_FB_ADRS framebuffer address
528 VIDEO_KBD_INIT_FCT keyboard int fct
529 (i.e. i8042_kbd_init())
530 VIDEO_TSTC_FCT test char fct
532 VIDEO_GETC_FCT get char fct
534 CONFIG_CONSOLE_CURSOR cursor drawing on/off
535 (requires blink timer
537 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
538 CONFIG_CONSOLE_TIME display time/date info in
540 (requires CONFIG_CMD_DATE)
541 CONFIG_VIDEO_LOGO display Linux logo in
543 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
544 linux_logo.h for logo.
545 Requires CONFIG_VIDEO_LOGO
546 CONFIG_CONSOLE_EXTRA_INFO
547 additional board info beside
550 When CONFIG_CFB_CONSOLE is defined, video console is
551 default i/o. Serial console can be forced with
552 environment 'console=serial'.
554 When CONFIG_SILENT_CONSOLE is defined, all console
555 messages (by U-Boot and Linux!) can be silenced with
556 the "silent" environment variable. See
557 doc/README.silent for more information.
560 CONFIG_BAUDRATE - in bps
561 Select one of the baudrates listed in
562 CONFIG_SYS_BAUDRATE_TABLE, see below.
563 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
565 - Console Rx buffer length
566 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
567 the maximum receive buffer length for the SMC.
568 This option is actual only for 82xx and 8xx possible.
569 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
570 must be defined, to setup the maximum idle timeout for
573 - Boot Delay: CONFIG_BOOTDELAY - in seconds
574 Delay before automatically booting the default image;
575 set to -1 to disable autoboot.
577 See doc/README.autoboot for these options that
578 work with CONFIG_BOOTDELAY. None are required.
579 CONFIG_BOOT_RETRY_TIME
580 CONFIG_BOOT_RETRY_MIN
581 CONFIG_AUTOBOOT_KEYED
582 CONFIG_AUTOBOOT_PROMPT
583 CONFIG_AUTOBOOT_DELAY_STR
584 CONFIG_AUTOBOOT_STOP_STR
585 CONFIG_AUTOBOOT_DELAY_STR2
586 CONFIG_AUTOBOOT_STOP_STR2
587 CONFIG_ZERO_BOOTDELAY_CHECK
588 CONFIG_RESET_TO_RETRY
592 Only needed when CONFIG_BOOTDELAY is enabled;
593 define a command string that is automatically executed
594 when no character is read on the console interface
595 within "Boot Delay" after reset.
598 This can be used to pass arguments to the bootm
599 command. The value of CONFIG_BOOTARGS goes into the
600 environment value "bootargs".
602 CONFIG_RAMBOOT and CONFIG_NFSBOOT
603 The value of these goes into the environment as
604 "ramboot" and "nfsboot" respectively, and can be used
605 as a convenience, when switching between booting from
611 When this option is #defined, the existence of the
612 environment variable "preboot" will be checked
613 immediately before starting the CONFIG_BOOTDELAY
614 countdown and/or running the auto-boot command resp.
615 entering interactive mode.
617 This feature is especially useful when "preboot" is
618 automatically generated or modified. For an example
619 see the LWMON board specific code: here "preboot" is
620 modified when the user holds down a certain
621 combination of keys on the (special) keyboard when
624 - Serial Download Echo Mode:
626 If defined to 1, all characters received during a
627 serial download (using the "loads" command) are
628 echoed back. This might be needed by some terminal
629 emulations (like "cu"), but may as well just take
630 time on others. This setting #define's the initial
631 value of the "loads_echo" environment variable.
633 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
635 Select one of the baudrates listed in
636 CONFIG_SYS_BAUDRATE_TABLE, see below.
639 Monitor commands can be included or excluded
640 from the build by using the #include files
641 "config_cmd_all.h" and #undef'ing unwanted
642 commands, or using "config_cmd_default.h"
643 and augmenting with additional #define's
646 The default command configuration includes all commands
647 except those marked below with a "*".
649 CONFIG_CMD_ASKENV * ask for env variable
650 CONFIG_CMD_BDI bdinfo
651 CONFIG_CMD_BEDBUG * Include BedBug Debugger
652 CONFIG_CMD_BMP * BMP support
653 CONFIG_CMD_BSP * Board specific commands
654 CONFIG_CMD_BOOTD bootd
655 CONFIG_CMD_CACHE * icache, dcache
656 CONFIG_CMD_CONSOLE coninfo
657 CONFIG_CMD_CRC32 * crc32
658 CONFIG_CMD_DATE * support for RTC, date/time...
659 CONFIG_CMD_DHCP * DHCP support
660 CONFIG_CMD_DIAG * Diagnostics
661 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
662 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
663 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
664 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
665 CONFIG_CMD_DTT * Digital Therm and Thermostat
666 CONFIG_CMD_ECHO echo arguments
667 CONFIG_CMD_EDITENV edit env variable
668 CONFIG_CMD_EEPROM * EEPROM read/write support
669 CONFIG_CMD_ELF * bootelf, bootvx
670 CONFIG_CMD_EXPORTENV * export the environment
671 CONFIG_CMD_SAVEENV saveenv
672 CONFIG_CMD_FDC * Floppy Disk Support
673 CONFIG_CMD_FAT * FAT partition support
674 CONFIG_CMD_FDOS * Dos diskette Support
675 CONFIG_CMD_FLASH flinfo, erase, protect
676 CONFIG_CMD_FPGA FPGA device initialization support
677 CONFIG_CMD_GO * the 'go' command (exec code)
678 CONFIG_CMD_GREPENV * search environment
679 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
680 CONFIG_CMD_I2C * I2C serial bus support
681 CONFIG_CMD_IDE * IDE harddisk support
682 CONFIG_CMD_IMI iminfo
683 CONFIG_CMD_IMLS List all found images
684 CONFIG_CMD_IMMAP * IMMR dump support
685 CONFIG_CMD_IMPORTENV * import an environment
686 CONFIG_CMD_IRQ * irqinfo
687 CONFIG_CMD_ITEST Integer/string test of 2 values
688 CONFIG_CMD_JFFS2 * JFFS2 Support
689 CONFIG_CMD_KGDB * kgdb
690 CONFIG_CMD_LDRINFO ldrinfo (display Blackfin loader)
691 CONFIG_CMD_LOADB loadb
692 CONFIG_CMD_LOADS loads
693 CONFIG_CMD_MD5SUM print md5 message digest
694 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
695 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
697 CONFIG_CMD_MISC Misc functions like sleep etc
698 CONFIG_CMD_MMC * MMC memory mapped support
699 CONFIG_CMD_MII * MII utility commands
700 CONFIG_CMD_MTDPARTS * MTD partition support
701 CONFIG_CMD_NAND * NAND support
702 CONFIG_CMD_NET bootp, tftpboot, rarpboot
703 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
704 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
705 CONFIG_CMD_PCI * pciinfo
706 CONFIG_CMD_PCMCIA * PCMCIA support
707 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
709 CONFIG_CMD_PORTIO * Port I/O
710 CONFIG_CMD_REGINFO * Register dump
711 CONFIG_CMD_RUN run command in env variable
712 CONFIG_CMD_SAVES * save S record dump
713 CONFIG_CMD_SCSI * SCSI Support
714 CONFIG_CMD_SDRAM * print SDRAM configuration information
715 (requires CONFIG_CMD_I2C)
716 CONFIG_CMD_SETGETDCR Support for DCR Register access
718 CONFIG_CMD_SHA1SUM print sha1 memory digest
719 (requires CONFIG_CMD_MEMORY)
720 CONFIG_CMD_SOURCE "source" command Support
721 CONFIG_CMD_SPI * SPI serial bus support
722 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
723 CONFIG_CMD_USB * USB support
724 CONFIG_CMD_CDP * Cisco Discover Protocol support
725 CONFIG_CMD_FSL * Microblaze FSL support
728 EXAMPLE: If you want all functions except of network
729 support you can write:
731 #include "config_cmd_all.h"
732 #undef CONFIG_CMD_NET
735 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
737 Note: Don't enable the "icache" and "dcache" commands
738 (configuration option CONFIG_CMD_CACHE) unless you know
739 what you (and your U-Boot users) are doing. Data
740 cache cannot be enabled on systems like the 8xx or
741 8260 (where accesses to the IMMR region must be
742 uncached), and it cannot be disabled on all other
743 systems where we (mis-) use the data cache to hold an
744 initial stack and some data.
747 XXX - this list needs to get updated!
751 If this variable is defined, it enables watchdog
752 support for the SoC. There must be support in the SoC
753 specific code for a watchdog. For the 8xx and 8260
754 CPUs, the SIU Watchdog feature is enabled in the SYPCR
755 register. When supported for a specific SoC is
756 available, then no further board specific code should
760 When using a watchdog circuitry external to the used
761 SoC, then define this variable and provide board
762 specific code for the "hw_watchdog_reset" function.
765 CONFIG_VERSION_VARIABLE
766 If this variable is defined, an environment variable
767 named "ver" is created by U-Boot showing the U-Boot
768 version as printed by the "version" command.
769 This variable is readonly.
773 When CONFIG_CMD_DATE is selected, the type of the RTC
774 has to be selected, too. Define exactly one of the
777 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
778 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
779 CONFIG_RTC_MC13783 - use MC13783 RTC
780 CONFIG_RTC_MC146818 - use MC146818 RTC
781 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
782 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
783 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
784 CONFIG_RTC_DS164x - use Dallas DS164x RTC
785 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
786 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
787 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
788 CONFIG_SYS_RV3029_TCR - enable trickle charger on
791 Note that if the RTC uses I2C, then the I2C interface
792 must also be configured. See I2C Support, below.
795 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
796 CONFIG_PCA953X_INFO - enable pca953x info command
798 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
799 chip-ngpio pairs that tell the PCA953X driver the number of
800 pins supported by a particular chip.
802 Note that if the GPIO device uses I2C, then the I2C interface
803 must also be configured. See I2C Support, below.
807 When CONFIG_TIMESTAMP is selected, the timestamp
808 (date and time) of an image is printed by image
809 commands like bootm or iminfo. This option is
810 automatically enabled when you select CONFIG_CMD_DATE .
813 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
814 and/or CONFIG_ISO_PARTITION and/or CONFIG_EFI_PARTITION
816 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
817 CONFIG_CMD_SCSI) you must configure support for at
818 least one partition type as well.
821 CONFIG_IDE_RESET_ROUTINE - this is defined in several
822 board configurations files but used nowhere!
824 CONFIG_IDE_RESET - is this is defined, IDE Reset will
825 be performed by calling the function
826 ide_set_reset(int reset)
827 which has to be defined in a board specific file
832 Set this to enable ATAPI support.
837 Set this to enable support for disks larger than 137GB
838 Also look at CONFIG_SYS_64BIT_LBA.
839 Whithout these , LBA48 support uses 32bit variables and will 'only'
840 support disks up to 2.1TB.
842 CONFIG_SYS_64BIT_LBA:
843 When enabled, makes the IDE subsystem use 64bit sector addresses.
847 At the moment only there is only support for the
848 SYM53C8XX SCSI controller; define
849 CONFIG_SCSI_SYM53C8XX to enable it.
851 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
852 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
853 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
854 maximum numbers of LUNs, SCSI ID's and target
856 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
858 - NETWORK Support (PCI):
860 Support for Intel 8254x gigabit chips.
862 CONFIG_E1000_FALLBACK_MAC
863 default MAC for empty EEPROM after production.
866 Support for Intel 82557/82559/82559ER chips.
867 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
868 write routine for first time initialisation.
871 Support for Digital 2114x chips.
872 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
873 modem chip initialisation (KS8761/QS6611).
876 Support for National dp83815 chips.
879 Support for National dp8382[01] gigabit chips.
881 - NETWORK Support (other):
883 CONFIG_DRIVER_AT91EMAC
884 Support for AT91RM9200 EMAC.
887 Define this to use reduced MII inteface
889 CONFIG_DRIVER_AT91EMAC_QUIET
890 If this defined, the driver is quiet.
891 The driver doen't show link status messages.
893 CONFIG_DRIVER_LAN91C96
894 Support for SMSC's LAN91C96 chips.
897 Define this to hold the physical address
898 of the LAN91C96's I/O space
900 CONFIG_LAN91C96_USE_32_BIT
901 Define this to enable 32 bit addressing
903 CONFIG_DRIVER_SMC91111
904 Support for SMSC's LAN91C111 chip
907 Define this to hold the physical address
908 of the device (I/O space)
910 CONFIG_SMC_USE_32_BIT
911 Define this if data bus is 32 bits
913 CONFIG_SMC_USE_IOFUNCS
914 Define this to use i/o functions instead of macros
915 (some hardware wont work with macros)
918 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
920 CONFIG_FTGMAC100_EGIGA
921 Define this to use GE link update with gigabit PHY.
922 Define this if FTGMAC100 is connected to gigabit PHY.
923 If your system has 10/100 PHY only, it might not occur
924 wrong behavior. Because PHY usually return timeout or
925 useless data when polling gigabit status and gigabit
926 control registers. This behavior won't affect the
927 correctnessof 10/100 link speed update.
930 Support for SMSC's LAN911x and LAN921x chips
933 Define this to hold the physical address
934 of the device (I/O space)
936 CONFIG_SMC911X_32_BIT
937 Define this if data bus is 32 bits
939 CONFIG_SMC911X_16_BIT
940 Define this if data bus is 16 bits. If your processor
941 automatically converts one 32 bit word to two 16 bit
942 words you may also try CONFIG_SMC911X_32_BIT.
945 Support for Renesas on-chip Ethernet controller
947 CONFIG_SH_ETHER_USE_PORT
948 Define the number of ports to be used
950 CONFIG_SH_ETHER_PHY_ADDR
951 Define the ETH PHY's address
953 CONFIG_SH_ETHER_CACHE_WRITEBACK
954 If this option is set, the driver enables cache flush.
957 At the moment only the UHCI host controller is
958 supported (PIP405, MIP405, MPC5200); define
959 CONFIG_USB_UHCI to enable it.
960 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
961 and define CONFIG_USB_STORAGE to enable the USB
964 Supported are USB Keyboards and USB Floppy drives
966 MPC5200 USB requires additional defines:
968 for 528 MHz Clock: 0x0001bbbb
972 for differential drivers: 0x00001000
973 for single ended drivers: 0x00005000
974 for differential drivers on PSC3: 0x00000100
975 for single ended drivers on PSC3: 0x00004100
976 CONFIG_SYS_USB_EVENT_POLL
977 May be defined to allow interrupt polling
978 instead of using asynchronous interrupts
981 Define the below if you wish to use the USB console.
982 Once firmware is rebuilt from a serial console issue the
983 command "setenv stdin usbtty; setenv stdout usbtty" and
984 attach your USB cable. The Unix command "dmesg" should print
985 it has found a new device. The environment variable usbtty
986 can be set to gserial or cdc_acm to enable your device to
987 appear to a USB host as a Linux gserial device or a
988 Common Device Class Abstract Control Model serial device.
989 If you select usbtty = gserial you should be able to enumerate
991 # modprobe usbserial vendor=0xVendorID product=0xProductID
992 else if using cdc_acm, simply setting the environment
993 variable usbtty to be cdc_acm should suffice. The following
994 might be defined in YourBoardName.h
997 Define this to build a UDC device
1000 Define this to have a tty type of device available to
1001 talk to the UDC device
1003 CONFIG_SYS_CONSOLE_IS_IN_ENV
1004 Define this if you want stdin, stdout &/or stderr to
1008 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
1009 Derive USB clock from external clock "blah"
1010 - CONFIG_SYS_USB_EXTC_CLK 0x02
1012 CONFIG_SYS_USB_BRG_CLK 0xBLAH
1013 Derive USB clock from brgclk
1014 - CONFIG_SYS_USB_BRG_CLK 0x04
1016 If you have a USB-IF assigned VendorID then you may wish to
1017 define your own vendor specific values either in BoardName.h
1018 or directly in usbd_vendor_info.h. If you don't define
1019 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1020 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1021 should pretend to be a Linux device to it's target host.
1023 CONFIG_USBD_MANUFACTURER
1024 Define this string as the name of your company for
1025 - CONFIG_USBD_MANUFACTURER "my company"
1027 CONFIG_USBD_PRODUCT_NAME
1028 Define this string as the name of your product
1029 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1031 CONFIG_USBD_VENDORID
1032 Define this as your assigned Vendor ID from the USB
1033 Implementors Forum. This *must* be a genuine Vendor ID
1034 to avoid polluting the USB namespace.
1035 - CONFIG_USBD_VENDORID 0xFFFF
1037 CONFIG_USBD_PRODUCTID
1038 Define this as the unique Product ID
1040 - CONFIG_USBD_PRODUCTID 0xFFFF
1044 The MMC controller on the Intel PXA is supported. To
1045 enable this define CONFIG_MMC. The MMC can be
1046 accessed from the boot prompt by mapping the device
1047 to physical memory similar to flash. Command line is
1048 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1049 the FAT fs. This is enabled with CONFIG_CMD_FAT.
1051 - Journaling Flash filesystem support:
1052 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1053 CONFIG_JFFS2_NAND_DEV
1054 Define these for a default partition on a NAND device
1056 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1057 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1058 Define these for a default partition on a NOR device
1060 CONFIG_SYS_JFFS_CUSTOM_PART
1061 Define this to create an own partition. You have to provide a
1062 function struct part_info* jffs2_part_info(int part_num)
1064 If you define only one JFFS2 partition you may also want to
1065 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1066 to disable the command chpart. This is the default when you
1067 have not defined a custom partition
1072 Define this to enable standard (PC-Style) keyboard
1076 Standard PC keyboard driver with US (is default) and
1077 GERMAN key layout (switch via environment 'keymap=de') support.
1078 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1079 for cfb_console. Supports cursor blinking.
1084 Define this to enable video support (for output to
1087 CONFIG_VIDEO_CT69000
1089 Enable Chips & Technologies 69000 Video chip
1091 CONFIG_VIDEO_SMI_LYNXEM
1092 Enable Silicon Motion SMI 712/710/810 Video chip. The
1093 video output is selected via environment 'videoout'
1094 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1097 For the CT69000 and SMI_LYNXEM drivers, videomode is
1098 selected via environment 'videomode'. Two different ways
1100 - "videomode=num" 'num' is a standard LiLo mode numbers.
1101 Following standard modes are supported (* is default):
1103 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1104 -------------+---------------------------------------------
1105 8 bits | 0x301* 0x303 0x305 0x161 0x307
1106 15 bits | 0x310 0x313 0x316 0x162 0x319
1107 16 bits | 0x311 0x314 0x317 0x163 0x31A
1108 24 bits | 0x312 0x315 0x318 ? 0x31B
1109 -------------+---------------------------------------------
1110 (i.e. setenv videomode 317; saveenv; reset;)
1112 - "videomode=bootargs" all the video parameters are parsed
1113 from the bootargs. (See drivers/video/videomodes.c)
1116 CONFIG_VIDEO_SED13806
1117 Enable Epson SED13806 driver. This driver supports 8bpp
1118 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1119 or CONFIG_VIDEO_SED13806_16BPP
1122 Enable the Freescale DIU video driver. Reference boards for
1123 SOCs that have a DIU should define this macro to enable DIU
1124 support, and should also define these other macros:
1130 CONFIG_VIDEO_SW_CURSOR
1131 CONFIG_VGA_AS_SINGLE_DEVICE
1133 CONFIG_VIDEO_BMP_LOGO
1135 The DIU driver will look for the 'video-mode' environment
1136 variable, and if defined, enable the DIU as a console during
1137 boot. See the documentation file README.video for a
1138 description of this variable.
1143 Define this to enable a custom keyboard support.
1144 This simply calls drv_keyboard_init() which must be
1145 defined in your board-specific files.
1146 The only board using this so far is RBC823.
1148 - LCD Support: CONFIG_LCD
1150 Define this to enable LCD support (for output to LCD
1151 display); also select one of the supported displays
1152 by defining one of these:
1156 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1158 CONFIG_NEC_NL6448AC33:
1160 NEC NL6448AC33-18. Active, color, single scan.
1162 CONFIG_NEC_NL6448BC20
1164 NEC NL6448BC20-08. 6.5", 640x480.
1165 Active, color, single scan.
1167 CONFIG_NEC_NL6448BC33_54
1169 NEC NL6448BC33-54. 10.4", 640x480.
1170 Active, color, single scan.
1174 Sharp 320x240. Active, color, single scan.
1175 It isn't 16x9, and I am not sure what it is.
1177 CONFIG_SHARP_LQ64D341
1179 Sharp LQ64D341 display, 640x480.
1180 Active, color, single scan.
1184 HLD1045 display, 640x480.
1185 Active, color, single scan.
1189 Optrex CBL50840-2 NF-FW 99 22 M5
1191 Hitachi LMG6912RPFC-00T
1195 320x240. Black & white.
1197 Normally display is black on white background; define
1198 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1200 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1202 If this option is set, the environment is checked for
1203 a variable "splashimage". If found, the usual display
1204 of logo, copyright and system information on the LCD
1205 is suppressed and the BMP image at the address
1206 specified in "splashimage" is loaded instead. The
1207 console is redirected to the "nulldev", too. This
1208 allows for a "silent" boot where a splash screen is
1209 loaded very quickly after power-on.
1211 CONFIG_SPLASH_SCREEN_ALIGN
1213 If this option is set the splash image can be freely positioned
1214 on the screen. Environment variable "splashpos" specifies the
1215 position as "x,y". If a positive number is given it is used as
1216 number of pixel from left/top. If a negative number is given it
1217 is used as number of pixel from right/bottom. You can also
1218 specify 'm' for centering the image.
1221 setenv splashpos m,m
1222 => image at center of screen
1224 setenv splashpos 30,20
1225 => image at x = 30 and y = 20
1227 setenv splashpos -10,m
1228 => vertically centered image
1229 at x = dspWidth - bmpWidth - 9
1231 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1233 If this option is set, additionally to standard BMP
1234 images, gzipped BMP images can be displayed via the
1235 splashscreen support or the bmp command.
1237 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1239 If this option is set, 8-bit RLE compressed BMP images
1240 can be displayed via the splashscreen support or the
1243 - Compression support:
1246 If this option is set, support for bzip2 compressed
1247 images is included. If not, only uncompressed and gzip
1248 compressed images are supported.
1250 NOTE: the bzip2 algorithm requires a lot of RAM, so
1251 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1256 If this option is set, support for lzma compressed
1259 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1260 requires an amount of dynamic memory that is given by the
1263 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1265 Where lc and lp stand for, respectively, Literal context bits
1266 and Literal pos bits.
1268 This value is upper-bounded by 14MB in the worst case. Anyway,
1269 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1270 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1271 a very small buffer.
1273 Use the lzmainfo tool to determinate the lc and lp values and
1274 then calculate the amount of needed dynamic memory (ensuring
1275 the appropriate CONFIG_SYS_MALLOC_LEN value).
1280 The address of PHY on MII bus.
1282 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1284 The clock frequency of the MII bus
1288 If this option is set, support for speed/duplex
1289 detection of gigabit PHY is included.
1291 CONFIG_PHY_RESET_DELAY
1293 Some PHY like Intel LXT971A need extra delay after
1294 reset before any MII register access is possible.
1295 For such PHY, set this option to the usec delay
1296 required. (minimum 300usec for LXT971A)
1298 CONFIG_PHY_CMD_DELAY (ppc4xx)
1300 Some PHY like Intel LXT971A need extra delay after
1301 command issued before MII status register can be read
1311 Define a default value for Ethernet address to use
1312 for the respective Ethernet interface, in case this
1313 is not determined automatically.
1318 Define a default value for the IP address to use for
1319 the default Ethernet interface, in case this is not
1320 determined through e.g. bootp.
1322 - Server IP address:
1325 Defines a default value for the IP address of a TFTP
1326 server to contact when using the "tftboot" command.
1328 CONFIG_KEEP_SERVERADDR
1330 Keeps the server's MAC address, in the env 'serveraddr'
1331 for passing to bootargs (like Linux's netconsole option)
1333 - Multicast TFTP Mode:
1336 Defines whether you want to support multicast TFTP as per
1337 rfc-2090; for example to work with atftp. Lets lots of targets
1338 tftp down the same boot image concurrently. Note: the Ethernet
1339 driver in use must provide a function: mcast() to join/leave a
1342 - BOOTP Recovery Mode:
1343 CONFIG_BOOTP_RANDOM_DELAY
1345 If you have many targets in a network that try to
1346 boot using BOOTP, you may want to avoid that all
1347 systems send out BOOTP requests at precisely the same
1348 moment (which would happen for instance at recovery
1349 from a power failure, when all systems will try to
1350 boot, thus flooding the BOOTP server. Defining
1351 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1352 inserted before sending out BOOTP requests. The
1353 following delays are inserted then:
1355 1st BOOTP request: delay 0 ... 1 sec
1356 2nd BOOTP request: delay 0 ... 2 sec
1357 3rd BOOTP request: delay 0 ... 4 sec
1359 BOOTP requests: delay 0 ... 8 sec
1361 - DHCP Advanced Options:
1362 You can fine tune the DHCP functionality by defining
1363 CONFIG_BOOTP_* symbols:
1365 CONFIG_BOOTP_SUBNETMASK
1366 CONFIG_BOOTP_GATEWAY
1367 CONFIG_BOOTP_HOSTNAME
1368 CONFIG_BOOTP_NISDOMAIN
1369 CONFIG_BOOTP_BOOTPATH
1370 CONFIG_BOOTP_BOOTFILESIZE
1373 CONFIG_BOOTP_SEND_HOSTNAME
1374 CONFIG_BOOTP_NTPSERVER
1375 CONFIG_BOOTP_TIMEOFFSET
1376 CONFIG_BOOTP_VENDOREX
1378 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1379 environment variable, not the BOOTP server.
1381 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1382 serverip from a DHCP server, it is possible that more
1383 than one DNS serverip is offered to the client.
1384 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1385 serverip will be stored in the additional environment
1386 variable "dnsip2". The first DNS serverip is always
1387 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1390 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1391 to do a dynamic update of a DNS server. To do this, they
1392 need the hostname of the DHCP requester.
1393 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1394 of the "hostname" environment variable is passed as
1395 option 12 to the DHCP server.
1397 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1399 A 32bit value in microseconds for a delay between
1400 receiving a "DHCP Offer" and sending the "DHCP Request".
1401 This fixes a problem with certain DHCP servers that don't
1402 respond 100% of the time to a "DHCP request". E.g. On an
1403 AT91RM9200 processor running at 180MHz, this delay needed
1404 to be *at least* 15,000 usec before a Windows Server 2003
1405 DHCP server would reply 100% of the time. I recommend at
1406 least 50,000 usec to be safe. The alternative is to hope
1407 that one of the retries will be successful but note that
1408 the DHCP timeout and retry process takes a longer than
1412 CONFIG_CDP_DEVICE_ID
1414 The device id used in CDP trigger frames.
1416 CONFIG_CDP_DEVICE_ID_PREFIX
1418 A two character string which is prefixed to the MAC address
1423 A printf format string which contains the ascii name of
1424 the port. Normally is set to "eth%d" which sets
1425 eth0 for the first Ethernet, eth1 for the second etc.
1427 CONFIG_CDP_CAPABILITIES
1429 A 32bit integer which indicates the device capabilities;
1430 0x00000010 for a normal host which does not forwards.
1434 An ascii string containing the version of the software.
1438 An ascii string containing the name of the platform.
1442 A 32bit integer sent on the trigger.
1444 CONFIG_CDP_POWER_CONSUMPTION
1446 A 16bit integer containing the power consumption of the
1447 device in .1 of milliwatts.
1449 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1451 A byte containing the id of the VLAN.
1453 - Status LED: CONFIG_STATUS_LED
1455 Several configurations allow to display the current
1456 status using a LED. For instance, the LED will blink
1457 fast while running U-Boot code, stop blinking as
1458 soon as a reply to a BOOTP request was received, and
1459 start blinking slow once the Linux kernel is running
1460 (supported by a status LED driver in the Linux
1461 kernel). Defining CONFIG_STATUS_LED enables this
1464 - CAN Support: CONFIG_CAN_DRIVER
1466 Defining CONFIG_CAN_DRIVER enables CAN driver support
1467 on those systems that support this (optional)
1468 feature, like the TQM8xxL modules.
1470 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1472 These enable I2C serial bus commands. Defining either of
1473 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1474 include the appropriate I2C driver for the selected CPU.
1476 This will allow you to use i2c commands at the u-boot
1477 command line (as long as you set CONFIG_CMD_I2C in
1478 CONFIG_COMMANDS) and communicate with i2c based realtime
1479 clock chips. See common/cmd_i2c.c for a description of the
1480 command line interface.
1482 CONFIG_HARD_I2C selects a hardware I2C controller.
1484 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1485 bit-banging) driver instead of CPM or similar hardware
1488 There are several other quantities that must also be
1489 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1491 In both cases you will need to define CONFIG_SYS_I2C_SPEED
1492 to be the frequency (in Hz) at which you wish your i2c bus
1493 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
1494 the CPU's i2c node address).
1496 Now, the u-boot i2c code for the mpc8xx
1497 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
1498 and so its address should therefore be cleared to 0 (See,
1499 eg, MPC823e User's Manual p.16-473). So, set
1500 CONFIG_SYS_I2C_SLAVE to 0.
1502 CONFIG_SYS_I2C_INIT_MPC5XXX
1504 When a board is reset during an i2c bus transfer
1505 chips might think that the current transfer is still
1506 in progress. Reset the slave devices by sending start
1507 commands until the slave device responds.
1509 That's all that's required for CONFIG_HARD_I2C.
1511 If you use the software i2c interface (CONFIG_SOFT_I2C)
1512 then the following macros need to be defined (examples are
1513 from include/configs/lwmon.h):
1517 (Optional). Any commands necessary to enable the I2C
1518 controller or configure ports.
1520 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1524 (Only for MPC8260 CPU). The I/O port to use (the code
1525 assumes both bits are on the same port). Valid values
1526 are 0..3 for ports A..D.
1530 The code necessary to make the I2C data line active
1531 (driven). If the data line is open collector, this
1534 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1538 The code necessary to make the I2C data line tri-stated
1539 (inactive). If the data line is open collector, this
1542 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1546 Code that returns TRUE if the I2C data line is high,
1549 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1553 If <bit> is TRUE, sets the I2C data line high. If it
1554 is FALSE, it clears it (low).
1556 eg: #define I2C_SDA(bit) \
1557 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1558 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1562 If <bit> is TRUE, sets the I2C clock line high. If it
1563 is FALSE, it clears it (low).
1565 eg: #define I2C_SCL(bit) \
1566 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1567 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1571 This delay is invoked four times per clock cycle so this
1572 controls the rate of data transfer. The data rate thus
1573 is 1 / (I2C_DELAY * 4). Often defined to be something
1576 #define I2C_DELAY udelay(2)
1578 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
1580 If your arch supports the generic GPIO framework (asm/gpio.h),
1581 then you may alternatively define the two GPIOs that are to be
1582 used as SCL / SDA. Any of the previous I2C_xxx macros will
1583 have GPIO-based defaults assigned to them as appropriate.
1585 You should define these to the GPIO value as given directly to
1586 the generic GPIO functions.
1588 CONFIG_SYS_I2C_INIT_BOARD
1590 When a board is reset during an i2c bus transfer
1591 chips might think that the current transfer is still
1592 in progress. On some boards it is possible to access
1593 the i2c SCLK line directly, either by using the
1594 processor pin as a GPIO or by having a second pin
1595 connected to the bus. If this option is defined a
1596 custom i2c_init_board() routine in boards/xxx/board.c
1597 is run early in the boot sequence.
1599 CONFIG_SYS_I2C_BOARD_LATE_INIT
1601 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
1602 defined a custom i2c_board_late_init() routine in
1603 boards/xxx/board.c is run AFTER the operations in i2c_init()
1604 is completed. This callpoint can be used to unreset i2c bus
1605 using CPU i2c controller register accesses for CPUs whose i2c
1606 controller provide such a method. It is called at the end of
1607 i2c_init() to allow i2c_init operations to setup the i2c bus
1608 controller on the CPU (e.g. setting bus speed & slave address).
1610 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
1612 This option enables configuration of bi_iic_fast[] flags
1613 in u-boot bd_info structure based on u-boot environment
1614 variable "i2cfast". (see also i2cfast)
1616 CONFIG_I2C_MULTI_BUS
1618 This option allows the use of multiple I2C buses, each of which
1619 must have a controller. At any point in time, only one bus is
1620 active. To switch to a different bus, use the 'i2c dev' command.
1621 Note that bus numbering is zero-based.
1623 CONFIG_SYS_I2C_NOPROBES
1625 This option specifies a list of I2C devices that will be skipped
1626 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
1627 is set, specify a list of bus-device pairs. Otherwise, specify
1628 a 1D array of device addresses
1631 #undef CONFIG_I2C_MULTI_BUS
1632 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
1634 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1636 #define CONFIG_I2C_MULTI_BUS
1637 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
1639 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1641 CONFIG_SYS_SPD_BUS_NUM
1643 If defined, then this indicates the I2C bus number for DDR SPD.
1644 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1646 CONFIG_SYS_RTC_BUS_NUM
1648 If defined, then this indicates the I2C bus number for the RTC.
1649 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1651 CONFIG_SYS_DTT_BUS_NUM
1653 If defined, then this indicates the I2C bus number for the DTT.
1654 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
1656 CONFIG_SYS_I2C_DTT_ADDR:
1658 If defined, specifies the I2C address of the DTT device.
1659 If not defined, then U-Boot uses predefined value for
1660 specified DTT device.
1664 Define this option if you want to use Freescale's I2C driver in
1665 drivers/i2c/fsl_i2c.c.
1669 Define this option if you have I2C devices reached over 1 .. n
1670 I2C Muxes like the pca9544a. This option addes a new I2C
1671 Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a
1672 new I2C Bus to the existing I2C Busses. If you select the
1673 new Bus with "i2c dev", u-bbot sends first the commandos for
1674 the muxes to activate this new "bus".
1676 CONFIG_I2C_MULTI_BUS must be also defined, to use this
1680 Adding a new I2C Bus reached over 2 pca9544a muxes
1681 The First mux with address 70 and channel 6
1682 The Second mux with address 71 and channel 4
1684 => i2c bus pca9544a:70:6:pca9544a:71:4
1686 Use the "i2c bus" command without parameter, to get a list
1687 of I2C Busses with muxes:
1690 Busses reached over muxes:
1692 reached over Mux(es):
1695 reached over Mux(es):
1700 If you now switch to the new I2C Bus 3 with "i2c dev 3"
1701 u-boot sends First the Commando to the mux@70 to enable
1702 channel 6, and then the Commando to the mux@71 to enable
1705 After that, you can use the "normal" i2c commands as
1706 usual, to communicate with your I2C devices behind
1709 This option is actually implemented for the bitbanging
1710 algorithm in common/soft_i2c.c and for the Hardware I2C
1711 Bus on the MPC8260. But it should be not so difficult
1712 to add this option to other architectures.
1714 CONFIG_SOFT_I2C_READ_REPEATED_START
1716 defining this will force the i2c_read() function in
1717 the soft_i2c driver to perform an I2C repeated start
1718 between writing the address pointer and reading the
1719 data. If this define is omitted the default behaviour
1720 of doing a stop-start sequence will be used. Most I2C
1721 devices can use either method, but some require one or
1724 - SPI Support: CONFIG_SPI
1726 Enables SPI driver (so far only tested with
1727 SPI EEPROM, also an instance works with Crystal A/D and
1728 D/As on the SACSng board)
1732 Enables the driver for SPI controller on SuperH. Currently
1733 only SH7757 is supported.
1737 Enables extended (16-bit) SPI EEPROM addressing.
1738 (symmetrical to CONFIG_I2C_X)
1742 Enables a software (bit-bang) SPI driver rather than
1743 using hardware support. This is a general purpose
1744 driver that only requires three general I/O port pins
1745 (two outputs, one input) to function. If this is
1746 defined, the board configuration must define several
1747 SPI configuration items (port pins to use, etc). For
1748 an example, see include/configs/sacsng.h.
1752 Enables a hardware SPI driver for general-purpose reads
1753 and writes. As with CONFIG_SOFT_SPI, the board configuration
1754 must define a list of chip-select function pointers.
1755 Currently supported on some MPC8xxx processors. For an
1756 example, see include/configs/mpc8349emds.h.
1760 Enables the driver for the SPI controllers on i.MX and MXC
1761 SoCs. Currently only i.MX31 is supported.
1763 - FPGA Support: CONFIG_FPGA
1765 Enables FPGA subsystem.
1767 CONFIG_FPGA_<vendor>
1769 Enables support for specific chip vendors.
1772 CONFIG_FPGA_<family>
1774 Enables support for FPGA family.
1775 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
1779 Specify the number of FPGA devices to support.
1781 CONFIG_SYS_FPGA_PROG_FEEDBACK
1783 Enable printing of hash marks during FPGA configuration.
1785 CONFIG_SYS_FPGA_CHECK_BUSY
1787 Enable checks on FPGA configuration interface busy
1788 status by the configuration function. This option
1789 will require a board or device specific function to
1794 If defined, a function that provides delays in the FPGA
1795 configuration driver.
1797 CONFIG_SYS_FPGA_CHECK_CTRLC
1798 Allow Control-C to interrupt FPGA configuration
1800 CONFIG_SYS_FPGA_CHECK_ERROR
1802 Check for configuration errors during FPGA bitfile
1803 loading. For example, abort during Virtex II
1804 configuration if the INIT_B line goes low (which
1805 indicated a CRC error).
1807 CONFIG_SYS_FPGA_WAIT_INIT
1809 Maximum time to wait for the INIT_B line to deassert
1810 after PROB_B has been deasserted during a Virtex II
1811 FPGA configuration sequence. The default time is 500
1814 CONFIG_SYS_FPGA_WAIT_BUSY
1816 Maximum time to wait for BUSY to deassert during
1817 Virtex II FPGA configuration. The default is 5 ms.
1819 CONFIG_SYS_FPGA_WAIT_CONFIG
1821 Time to wait after FPGA configuration. The default is
1824 - Configuration Management:
1827 If defined, this string will be added to the U-Boot
1828 version information (U_BOOT_VERSION)
1830 - Vendor Parameter Protection:
1832 U-Boot considers the values of the environment
1833 variables "serial#" (Board Serial Number) and
1834 "ethaddr" (Ethernet Address) to be parameters that
1835 are set once by the board vendor / manufacturer, and
1836 protects these variables from casual modification by
1837 the user. Once set, these variables are read-only,
1838 and write or delete attempts are rejected. You can
1839 change this behaviour:
1841 If CONFIG_ENV_OVERWRITE is #defined in your config
1842 file, the write protection for vendor parameters is
1843 completely disabled. Anybody can change or delete
1846 Alternatively, if you #define _both_ CONFIG_ETHADDR
1847 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1848 Ethernet address is installed in the environment,
1849 which can be changed exactly ONCE by the user. [The
1850 serial# is unaffected by this, i. e. it remains
1856 Define this variable to enable the reservation of
1857 "protected RAM", i. e. RAM which is not overwritten
1858 by U-Boot. Define CONFIG_PRAM to hold the number of
1859 kB you want to reserve for pRAM. You can overwrite
1860 this default value by defining an environment
1861 variable "pram" to the number of kB you want to
1862 reserve. Note that the board info structure will
1863 still show the full amount of RAM. If pRAM is
1864 reserved, a new environment variable "mem" will
1865 automatically be defined to hold the amount of
1866 remaining RAM in a form that can be passed as boot
1867 argument to Linux, for instance like that:
1869 setenv bootargs ... mem=\${mem}
1872 This way you can tell Linux not to use this memory,
1873 either, which results in a memory region that will
1874 not be affected by reboots.
1876 *WARNING* If your board configuration uses automatic
1877 detection of the RAM size, you must make sure that
1878 this memory test is non-destructive. So far, the
1879 following board configurations are known to be
1882 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1883 HERMES, IP860, RPXlite, LWMON, LANTEC,
1889 Define this variable to stop the system in case of a
1890 fatal error, so that you have to reset it manually.
1891 This is probably NOT a good idea for an embedded
1892 system where you want the system to reboot
1893 automatically as fast as possible, but it may be
1894 useful during development since you can try to debug
1895 the conditions that lead to the situation.
1897 CONFIG_NET_RETRY_COUNT
1899 This variable defines the number of retries for
1900 network operations like ARP, RARP, TFTP, or BOOTP
1901 before giving up the operation. If not defined, a
1902 default value of 5 is used.
1906 Timeout waiting for an ARP reply in milliseconds.
1908 - Command Interpreter:
1909 CONFIG_AUTO_COMPLETE
1911 Enable auto completion of commands using TAB.
1913 Note that this feature has NOT been implemented yet
1914 for the "hush" shell.
1917 CONFIG_SYS_HUSH_PARSER
1919 Define this variable to enable the "hush" shell (from
1920 Busybox) as command line interpreter, thus enabling
1921 powerful command line syntax like
1922 if...then...else...fi conditionals or `&&' and '||'
1923 constructs ("shell scripts").
1925 If undefined, you get the old, much simpler behaviour
1926 with a somewhat smaller memory footprint.
1929 CONFIG_SYS_PROMPT_HUSH_PS2
1931 This defines the secondary prompt string, which is
1932 printed when the command interpreter needs more input
1933 to complete a command. Usually "> ".
1937 In the current implementation, the local variables
1938 space and global environment variables space are
1939 separated. Local variables are those you define by
1940 simply typing `name=value'. To access a local
1941 variable later on, you have write `$name' or
1942 `${name}'; to execute the contents of a variable
1943 directly type `$name' at the command prompt.
1945 Global environment variables are those you use
1946 setenv/printenv to work with. To run a command stored
1947 in such a variable, you need to use the run command,
1948 and you must not use the '$' sign to access them.
1950 To store commands and special characters in a
1951 variable, please use double quotation marks
1952 surrounding the whole text of the variable, instead
1953 of the backslashes before semicolons and special
1956 - Commandline Editing and History:
1957 CONFIG_CMDLINE_EDITING
1959 Enable editing and History functions for interactive
1960 commandline input operations
1962 - Default Environment:
1963 CONFIG_EXTRA_ENV_SETTINGS
1965 Define this to contain any number of null terminated
1966 strings (variable = value pairs) that will be part of
1967 the default environment compiled into the boot image.
1969 For example, place something like this in your
1970 board's config file:
1972 #define CONFIG_EXTRA_ENV_SETTINGS \
1976 Warning: This method is based on knowledge about the
1977 internal format how the environment is stored by the
1978 U-Boot code. This is NOT an official, exported
1979 interface! Although it is unlikely that this format
1980 will change soon, there is no guarantee either.
1981 You better know what you are doing here.
1983 Note: overly (ab)use of the default environment is
1984 discouraged. Make sure to check other ways to preset
1985 the environment like the "source" command or the
1988 - DataFlash Support:
1989 CONFIG_HAS_DATAFLASH
1991 Defining this option enables DataFlash features and
1992 allows to read/write in Dataflash via the standard
1995 - SystemACE Support:
1998 Adding this option adds support for Xilinx SystemACE
1999 chips attached via some sort of local bus. The address
2000 of the chip must also be defined in the
2001 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
2003 #define CONFIG_SYSTEMACE
2004 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
2006 When SystemACE support is added, the "ace" device type
2007 becomes available to the fat commands, i.e. fatls.
2009 - TFTP Fixed UDP Port:
2012 If this is defined, the environment variable tftpsrcp
2013 is used to supply the TFTP UDP source port value.
2014 If tftpsrcp isn't defined, the normal pseudo-random port
2015 number generator is used.
2017 Also, the environment variable tftpdstp is used to supply
2018 the TFTP UDP destination port value. If tftpdstp isn't
2019 defined, the normal port 69 is used.
2021 The purpose for tftpsrcp is to allow a TFTP server to
2022 blindly start the TFTP transfer using the pre-configured
2023 target IP address and UDP port. This has the effect of
2024 "punching through" the (Windows XP) firewall, allowing
2025 the remainder of the TFTP transfer to proceed normally.
2026 A better solution is to properly configure the firewall,
2027 but sometimes that is not allowed.
2029 - Show boot progress:
2030 CONFIG_SHOW_BOOT_PROGRESS
2032 Defining this option allows to add some board-
2033 specific code (calling a user-provided function
2034 "show_boot_progress(int)") that enables you to show
2035 the system's boot progress on some display (for
2036 example, some LED's) on your board. At the moment,
2037 the following checkpoints are implemented:
2039 - Standalone program support:
2040 CONFIG_STANDALONE_LOAD_ADDR
2042 This option allows to define board specific values
2043 for the address where standalone program gets loaded,
2044 thus overwriting the architecutre dependent default
2047 - Frame Buffer Address:
2050 Define CONFIG_FB_ADDR if you want to use specific address for
2052 Then system will reserve the frame buffer address to defined address
2053 instead of lcd_setmem (this function grab the memory for frame buffer
2056 Please see board_init_f function.
2058 If you want this config option then,
2059 please define it at your board config file
2061 Legacy uImage format:
2064 1 common/cmd_bootm.c before attempting to boot an image
2065 -1 common/cmd_bootm.c Image header has bad magic number
2066 2 common/cmd_bootm.c Image header has correct magic number
2067 -2 common/cmd_bootm.c Image header has bad checksum
2068 3 common/cmd_bootm.c Image header has correct checksum
2069 -3 common/cmd_bootm.c Image data has bad checksum
2070 4 common/cmd_bootm.c Image data has correct checksum
2071 -4 common/cmd_bootm.c Image is for unsupported architecture
2072 5 common/cmd_bootm.c Architecture check OK
2073 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
2074 6 common/cmd_bootm.c Image Type check OK
2075 -6 common/cmd_bootm.c gunzip uncompression error
2076 -7 common/cmd_bootm.c Unimplemented compression type
2077 7 common/cmd_bootm.c Uncompression OK
2078 8 common/cmd_bootm.c No uncompress/copy overwrite error
2079 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
2081 9 common/image.c Start initial ramdisk verification
2082 -10 common/image.c Ramdisk header has bad magic number
2083 -11 common/image.c Ramdisk header has bad checksum
2084 10 common/image.c Ramdisk header is OK
2085 -12 common/image.c Ramdisk data has bad checksum
2086 11 common/image.c Ramdisk data has correct checksum
2087 12 common/image.c Ramdisk verification complete, start loading
2088 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
2089 13 common/image.c Start multifile image verification
2090 14 common/image.c No initial ramdisk, no multifile, continue.
2092 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
2094 -30 arch/powerpc/lib/board.c Fatal error, hang the system
2095 -31 post/post.c POST test failed, detected by post_output_backlog()
2096 -32 post/post.c POST test failed, detected by post_run_single()
2098 34 common/cmd_doc.c before loading a Image from a DOC device
2099 -35 common/cmd_doc.c Bad usage of "doc" command
2100 35 common/cmd_doc.c correct usage of "doc" command
2101 -36 common/cmd_doc.c No boot device
2102 36 common/cmd_doc.c correct boot device
2103 -37 common/cmd_doc.c Unknown Chip ID on boot device
2104 37 common/cmd_doc.c correct chip ID found, device available
2105 -38 common/cmd_doc.c Read Error on boot device
2106 38 common/cmd_doc.c reading Image header from DOC device OK
2107 -39 common/cmd_doc.c Image header has bad magic number
2108 39 common/cmd_doc.c Image header has correct magic number
2109 -40 common/cmd_doc.c Error reading Image from DOC device
2110 40 common/cmd_doc.c Image header has correct magic number
2111 41 common/cmd_ide.c before loading a Image from a IDE device
2112 -42 common/cmd_ide.c Bad usage of "ide" command
2113 42 common/cmd_ide.c correct usage of "ide" command
2114 -43 common/cmd_ide.c No boot device
2115 43 common/cmd_ide.c boot device found
2116 -44 common/cmd_ide.c Device not available
2117 44 common/cmd_ide.c Device available
2118 -45 common/cmd_ide.c wrong partition selected
2119 45 common/cmd_ide.c partition selected
2120 -46 common/cmd_ide.c Unknown partition table
2121 46 common/cmd_ide.c valid partition table found
2122 -47 common/cmd_ide.c Invalid partition type
2123 47 common/cmd_ide.c correct partition type
2124 -48 common/cmd_ide.c Error reading Image Header on boot device
2125 48 common/cmd_ide.c reading Image Header from IDE device OK
2126 -49 common/cmd_ide.c Image header has bad magic number
2127 49 common/cmd_ide.c Image header has correct magic number
2128 -50 common/cmd_ide.c Image header has bad checksum
2129 50 common/cmd_ide.c Image header has correct checksum
2130 -51 common/cmd_ide.c Error reading Image from IDE device
2131 51 common/cmd_ide.c reading Image from IDE device OK
2132 52 common/cmd_nand.c before loading a Image from a NAND device
2133 -53 common/cmd_nand.c Bad usage of "nand" command
2134 53 common/cmd_nand.c correct usage of "nand" command
2135 -54 common/cmd_nand.c No boot device
2136 54 common/cmd_nand.c boot device found
2137 -55 common/cmd_nand.c Unknown Chip ID on boot device
2138 55 common/cmd_nand.c correct chip ID found, device available
2139 -56 common/cmd_nand.c Error reading Image Header on boot device
2140 56 common/cmd_nand.c reading Image Header from NAND device OK
2141 -57 common/cmd_nand.c Image header has bad magic number
2142 57 common/cmd_nand.c Image header has correct magic number
2143 -58 common/cmd_nand.c Error reading Image from NAND device
2144 58 common/cmd_nand.c reading Image from NAND device OK
2146 -60 common/env_common.c Environment has a bad CRC, using default
2148 64 net/eth.c starting with Ethernet configuration.
2149 -64 net/eth.c no Ethernet found.
2150 65 net/eth.c Ethernet found.
2152 -80 common/cmd_net.c usage wrong
2153 80 common/cmd_net.c before calling NetLoop()
2154 -81 common/cmd_net.c some error in NetLoop() occurred
2155 81 common/cmd_net.c NetLoop() back without error
2156 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2157 82 common/cmd_net.c trying automatic boot
2158 83 common/cmd_net.c running "source" command
2159 -83 common/cmd_net.c some error in automatic boot or "source" command
2160 84 common/cmd_net.c end without errors
2165 100 common/cmd_bootm.c Kernel FIT Image has correct format
2166 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2167 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2168 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2169 102 common/cmd_bootm.c Kernel unit name specified
2170 -103 common/cmd_bootm.c Can't get kernel subimage node offset
2171 103 common/cmd_bootm.c Found configuration node
2172 104 common/cmd_bootm.c Got kernel subimage node offset
2173 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2174 105 common/cmd_bootm.c Kernel subimage hash verification OK
2175 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2176 106 common/cmd_bootm.c Architecture check OK
2177 -106 common/cmd_bootm.c Kernel subimage has wrong type
2178 107 common/cmd_bootm.c Kernel subimage type OK
2179 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2180 108 common/cmd_bootm.c Got kernel subimage data/size
2181 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2182 -109 common/cmd_bootm.c Can't get kernel subimage type
2183 -110 common/cmd_bootm.c Can't get kernel subimage comp
2184 -111 common/cmd_bootm.c Can't get kernel subimage os
2185 -112 common/cmd_bootm.c Can't get kernel subimage load address
2186 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2188 120 common/image.c Start initial ramdisk verification
2189 -120 common/image.c Ramdisk FIT image has incorrect format
2190 121 common/image.c Ramdisk FIT image has correct format
2191 122 common/image.c No ramdisk subimage unit name, using configuration
2192 -122 common/image.c Can't get configuration for ramdisk subimage
2193 123 common/image.c Ramdisk unit name specified
2194 -124 common/image.c Can't get ramdisk subimage node offset
2195 125 common/image.c Got ramdisk subimage node offset
2196 -125 common/image.c Ramdisk subimage hash verification failed
2197 126 common/image.c Ramdisk subimage hash verification OK
2198 -126 common/image.c Ramdisk subimage for unsupported architecture
2199 127 common/image.c Architecture check OK
2200 -127 common/image.c Can't get ramdisk subimage data/size
2201 128 common/image.c Got ramdisk subimage data/size
2202 129 common/image.c Can't get ramdisk load address
2203 -129 common/image.c Got ramdisk load address
2205 -130 common/cmd_doc.c Incorrect FIT image format
2206 131 common/cmd_doc.c FIT image format OK
2208 -140 common/cmd_ide.c Incorrect FIT image format
2209 141 common/cmd_ide.c FIT image format OK
2211 -150 common/cmd_nand.c Incorrect FIT image format
2212 151 common/cmd_nand.c FIT image format OK
2214 - Automatic software updates via TFTP server
2216 CONFIG_UPDATE_TFTP_CNT_MAX
2217 CONFIG_UPDATE_TFTP_MSEC_MAX
2219 These options enable and control the auto-update feature;
2220 for a more detailed description refer to doc/README.update.
2222 - MTD Support (mtdparts command, UBI support)
2225 Adds the MTD device infrastructure from the Linux kernel.
2226 Needed for mtdparts command support.
2228 CONFIG_MTD_PARTITIONS
2230 Adds the MTD partitioning infrastructure from the Linux
2231 kernel. Needed for UBI support.
2237 [so far only for SMDK2400 boards]
2239 - Modem support enable:
2240 CONFIG_MODEM_SUPPORT
2242 - RTS/CTS Flow control enable:
2245 - Modem debug support:
2246 CONFIG_MODEM_SUPPORT_DEBUG
2248 Enables debugging stuff (char screen[1024], dbg())
2249 for modem support. Useful only with BDI2000.
2251 - Interrupt support (PPC):
2253 There are common interrupt_init() and timer_interrupt()
2254 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
2255 for CPU specific initialization. interrupt_init_cpu()
2256 should set decrementer_count to appropriate value. If
2257 CPU resets decrementer automatically after interrupt
2258 (ppc4xx) it should set decrementer_count to zero.
2259 timer_interrupt() calls timer_interrupt_cpu() for CPU
2260 specific handling. If board has watchdog / status_led
2261 / other_activity_monitor it works automatically from
2262 general timer_interrupt().
2266 In the target system modem support is enabled when a
2267 specific key (key combination) is pressed during
2268 power-on. Otherwise U-Boot will boot normally
2269 (autoboot). The key_pressed() function is called from
2270 board_init(). Currently key_pressed() is a dummy
2271 function, returning 1 and thus enabling modem
2274 If there are no modem init strings in the
2275 environment, U-Boot proceed to autoboot; the
2276 previous output (banner, info printfs) will be
2279 See also: doc/README.Modem
2282 Configuration Settings:
2283 -----------------------
2285 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
2286 undefine this when you're short of memory.
2288 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
2289 width of the commands listed in the 'help' command output.
2291 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
2292 prompt for user input.
2294 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
2296 - CONFIG_SYS_PBSIZE: Buffer size for Console output
2298 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
2300 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
2301 the application (usually a Linux kernel) when it is
2304 - CONFIG_SYS_BAUDRATE_TABLE:
2305 List of legal baudrate settings for this board.
2307 - CONFIG_SYS_CONSOLE_INFO_QUIET
2308 Suppress display of console information at boot.
2310 - CONFIG_SYS_CONSOLE_IS_IN_ENV
2311 If the board specific function
2312 extern int overwrite_console (void);
2313 returns 1, the stdin, stderr and stdout are switched to the
2314 serial port, else the settings in the environment are used.
2316 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
2317 Enable the call to overwrite_console().
2319 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
2320 Enable overwrite of previous console environment settings.
2322 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
2323 Begin and End addresses of the area used by the
2326 - CONFIG_SYS_ALT_MEMTEST:
2327 Enable an alternate, more extensive memory test.
2329 - CONFIG_SYS_MEMTEST_SCRATCH:
2330 Scratch address used by the alternate memory test
2331 You only need to set this if address zero isn't writeable
2333 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
2334 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
2335 this specified memory area will get subtracted from the top
2336 (end) of RAM and won't get "touched" at all by U-Boot. By
2337 fixing up gd->ram_size the Linux kernel should gets passed
2338 the now "corrected" memory size and won't touch it either.
2339 This should work for arch/ppc and arch/powerpc. Only Linux
2340 board ports in arch/powerpc with bootwrapper support that
2341 recalculate the memory size from the SDRAM controller setup
2342 will have to get fixed in Linux additionally.
2344 This option can be used as a workaround for the 440EPx/GRx
2345 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
2348 WARNING: Please make sure that this value is a multiple of
2349 the Linux page size (normally 4k). If this is not the case,
2350 then the end address of the Linux memory will be located at a
2351 non page size aligned address and this could cause major
2354 - CONFIG_SYS_TFTP_LOADADDR:
2355 Default load address for network file downloads
2357 - CONFIG_SYS_LOADS_BAUD_CHANGE:
2358 Enable temporary baudrate change while serial download
2360 - CONFIG_SYS_SDRAM_BASE:
2361 Physical start address of SDRAM. _Must_ be 0 here.
2363 - CONFIG_SYS_MBIO_BASE:
2364 Physical start address of Motherboard I/O (if using a
2367 - CONFIG_SYS_FLASH_BASE:
2368 Physical start address of Flash memory.
2370 - CONFIG_SYS_MONITOR_BASE:
2371 Physical start address of boot monitor code (set by
2372 make config files to be same as the text base address
2373 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
2374 CONFIG_SYS_FLASH_BASE when booting from flash.
2376 - CONFIG_SYS_MONITOR_LEN:
2377 Size of memory reserved for monitor code, used to
2378 determine _at_compile_time_ (!) if the environment is
2379 embedded within the U-Boot image, or in a separate
2382 - CONFIG_SYS_MALLOC_LEN:
2383 Size of DRAM reserved for malloc() use.
2385 - CONFIG_SYS_BOOTM_LEN:
2386 Normally compressed uImages are limited to an
2387 uncompressed size of 8 MBytes. If this is not enough,
2388 you can define CONFIG_SYS_BOOTM_LEN in your board config file
2389 to adjust this setting to your needs.
2391 - CONFIG_SYS_BOOTMAPSZ:
2392 Maximum size of memory mapped by the startup code of
2393 the Linux kernel; all data that must be processed by
2394 the Linux kernel (bd_info, boot arguments, FDT blob if
2395 used) must be put below this limit, unless "bootm_low"
2396 enviroment variable is defined and non-zero. In such case
2397 all data for the Linux kernel must be between "bootm_low"
2398 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
2399 variable "bootm_mapsize" will override the value of
2400 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
2401 then the value in "bootm_size" will be used instead.
2403 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
2404 Enable initrd_high functionality. If defined then the
2405 initrd_high feature is enabled and the bootm ramdisk subcommand
2408 - CONFIG_SYS_BOOT_GET_CMDLINE:
2409 Enables allocating and saving kernel cmdline in space between
2410 "bootm_low" and "bootm_low" + BOOTMAPSZ.
2412 - CONFIG_SYS_BOOT_GET_KBD:
2413 Enables allocating and saving a kernel copy of the bd_info in
2414 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
2416 - CONFIG_SYS_MAX_FLASH_BANKS:
2417 Max number of Flash memory banks
2419 - CONFIG_SYS_MAX_FLASH_SECT:
2420 Max number of sectors on a Flash chip
2422 - CONFIG_SYS_FLASH_ERASE_TOUT:
2423 Timeout for Flash erase operations (in ms)
2425 - CONFIG_SYS_FLASH_WRITE_TOUT:
2426 Timeout for Flash write operations (in ms)
2428 - CONFIG_SYS_FLASH_LOCK_TOUT
2429 Timeout for Flash set sector lock bit operation (in ms)
2431 - CONFIG_SYS_FLASH_UNLOCK_TOUT
2432 Timeout for Flash clear lock bits operation (in ms)
2434 - CONFIG_SYS_FLASH_PROTECTION
2435 If defined, hardware flash sectors protection is used
2436 instead of U-Boot software protection.
2438 - CONFIG_SYS_DIRECT_FLASH_TFTP:
2440 Enable TFTP transfers directly to flash memory;
2441 without this option such a download has to be
2442 performed in two steps: (1) download to RAM, and (2)
2443 copy from RAM to flash.
2445 The two-step approach is usually more reliable, since
2446 you can check if the download worked before you erase
2447 the flash, but in some situations (when system RAM is
2448 too limited to allow for a temporary copy of the
2449 downloaded image) this option may be very useful.
2451 - CONFIG_SYS_FLASH_CFI:
2452 Define if the flash driver uses extra elements in the
2453 common flash structure for storing flash geometry.
2455 - CONFIG_FLASH_CFI_DRIVER
2456 This option also enables the building of the cfi_flash driver
2457 in the drivers directory
2459 - CONFIG_FLASH_CFI_MTD
2460 This option enables the building of the cfi_mtd driver
2461 in the drivers directory. The driver exports CFI flash
2464 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
2465 Use buffered writes to flash.
2467 - CONFIG_FLASH_SPANSION_S29WS_N
2468 s29ws-n MirrorBit flash has non-standard addresses for buffered
2471 - CONFIG_SYS_FLASH_QUIET_TEST
2472 If this option is defined, the common CFI flash doesn't
2473 print it's warning upon not recognized FLASH banks. This
2474 is useful, if some of the configured banks are only
2475 optionally available.
2477 - CONFIG_FLASH_SHOW_PROGRESS
2478 If defined (must be an integer), print out countdown
2479 digits and dots. Recommended value: 45 (9..1) for 80
2480 column displays, 15 (3..1) for 40 column displays.
2482 - CONFIG_SYS_RX_ETH_BUFFER:
2483 Defines the number of Ethernet receive buffers. On some
2484 Ethernet controllers it is recommended to set this value
2485 to 8 or even higher (EEPRO100 or 405 EMAC), since all
2486 buffers can be full shortly after enabling the interface
2487 on high Ethernet traffic.
2488 Defaults to 4 if not defined.
2490 - CONFIG_ENV_MAX_ENTRIES
2492 Maximum number of entries in the hash table that is used
2493 internally to store the environment settings. The default
2494 setting is supposed to be generous and should work in most
2495 cases. This setting can be used to tune behaviour; see
2496 lib/hashtable.c for details.
2498 The following definitions that deal with the placement and management
2499 of environment data (variable area); in general, we support the
2500 following configurations:
2502 - CONFIG_ENV_IS_IN_FLASH:
2504 Define this if the environment is in flash memory.
2506 a) The environment occupies one whole flash sector, which is
2507 "embedded" in the text segment with the U-Boot code. This
2508 happens usually with "bottom boot sector" or "top boot
2509 sector" type flash chips, which have several smaller
2510 sectors at the start or the end. For instance, such a
2511 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
2512 such a case you would place the environment in one of the
2513 4 kB sectors - with U-Boot code before and after it. With
2514 "top boot sector" type flash chips, you would put the
2515 environment in one of the last sectors, leaving a gap
2516 between U-Boot and the environment.
2518 - CONFIG_ENV_OFFSET:
2520 Offset of environment data (variable area) to the
2521 beginning of flash memory; for instance, with bottom boot
2522 type flash chips the second sector can be used: the offset
2523 for this sector is given here.
2525 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
2529 This is just another way to specify the start address of
2530 the flash sector containing the environment (instead of
2533 - CONFIG_ENV_SECT_SIZE:
2535 Size of the sector containing the environment.
2538 b) Sometimes flash chips have few, equal sized, BIG sectors.
2539 In such a case you don't want to spend a whole sector for
2544 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
2545 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
2546 of this flash sector for the environment. This saves
2547 memory for the RAM copy of the environment.
2549 It may also save flash memory if you decide to use this
2550 when your environment is "embedded" within U-Boot code,
2551 since then the remainder of the flash sector could be used
2552 for U-Boot code. It should be pointed out that this is
2553 STRONGLY DISCOURAGED from a robustness point of view:
2554 updating the environment in flash makes it always
2555 necessary to erase the WHOLE sector. If something goes
2556 wrong before the contents has been restored from a copy in
2557 RAM, your target system will be dead.
2559 - CONFIG_ENV_ADDR_REDUND
2560 CONFIG_ENV_SIZE_REDUND
2562 These settings describe a second storage area used to hold
2563 a redundant copy of the environment data, so that there is
2564 a valid backup copy in case there is a power failure during
2565 a "saveenv" operation.
2567 BE CAREFUL! Any changes to the flash layout, and some changes to the
2568 source code will make it necessary to adapt <board>/u-boot.lds*
2572 - CONFIG_ENV_IS_IN_NVRAM:
2574 Define this if you have some non-volatile memory device
2575 (NVRAM, battery buffered SRAM) which you want to use for the
2581 These two #defines are used to determine the memory area you
2582 want to use for environment. It is assumed that this memory
2583 can just be read and written to, without any special
2586 BE CAREFUL! The first access to the environment happens quite early
2587 in U-Boot initalization (when we try to get the setting of for the
2588 console baudrate). You *MUST* have mapped your NVRAM area then, or
2591 Please note that even with NVRAM we still use a copy of the
2592 environment in RAM: we could work on NVRAM directly, but we want to
2593 keep settings there always unmodified except somebody uses "saveenv"
2594 to save the current settings.
2597 - CONFIG_ENV_IS_IN_EEPROM:
2599 Use this if you have an EEPROM or similar serial access
2600 device and a driver for it.
2602 - CONFIG_ENV_OFFSET:
2605 These two #defines specify the offset and size of the
2606 environment area within the total memory of your EEPROM.
2608 - CONFIG_SYS_I2C_EEPROM_ADDR:
2609 If defined, specified the chip address of the EEPROM device.
2610 The default address is zero.
2612 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
2613 If defined, the number of bits used to address bytes in a
2614 single page in the EEPROM device. A 64 byte page, for example
2615 would require six bits.
2617 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
2618 If defined, the number of milliseconds to delay between
2619 page writes. The default is zero milliseconds.
2621 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
2622 The length in bytes of the EEPROM memory array address. Note
2623 that this is NOT the chip address length!
2625 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
2626 EEPROM chips that implement "address overflow" are ones
2627 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
2628 address and the extra bits end up in the "chip address" bit
2629 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
2632 Note that we consider the length of the address field to
2633 still be one byte because the extra address bits are hidden
2634 in the chip address.
2636 - CONFIG_SYS_EEPROM_SIZE:
2637 The size in bytes of the EEPROM device.
2639 - CONFIG_ENV_EEPROM_IS_ON_I2C
2640 define this, if you have I2C and SPI activated, and your
2641 EEPROM, which holds the environment, is on the I2C bus.
2643 - CONFIG_I2C_ENV_EEPROM_BUS
2644 if you have an Environment on an EEPROM reached over
2645 I2C muxes, you can define here, how to reach this
2646 EEPROM. For example:
2648 #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0"
2650 EEPROM which holds the environment, is reached over
2651 a pca9547 i2c mux with address 0x70, channel 3.
2653 - CONFIG_ENV_IS_IN_DATAFLASH:
2655 Define this if you have a DataFlash memory device which you
2656 want to use for the environment.
2658 - CONFIG_ENV_OFFSET:
2662 These three #defines specify the offset and size of the
2663 environment area within the total memory of your DataFlash placed
2664 at the specified address.
2666 - CONFIG_ENV_IS_IN_NAND:
2668 Define this if you have a NAND device which you want to use
2669 for the environment.
2671 - CONFIG_ENV_OFFSET:
2674 These two #defines specify the offset and size of the environment
2675 area within the first NAND device. CONFIG_ENV_OFFSET must be
2676 aligned to an erase block boundary.
2678 - CONFIG_ENV_OFFSET_REDUND (optional):
2680 This setting describes a second storage area of CONFIG_ENV_SIZE
2681 size used to hold a redundant copy of the environment data, so
2682 that there is a valid backup copy in case there is a power failure
2683 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
2684 aligned to an erase block boundary.
2686 - CONFIG_ENV_RANGE (optional):
2688 Specifies the length of the region in which the environment
2689 can be written. This should be a multiple of the NAND device's
2690 block size. Specifying a range with more erase blocks than
2691 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
2692 the range to be avoided.
2694 - CONFIG_ENV_OFFSET_OOB (optional):
2696 Enables support for dynamically retrieving the offset of the
2697 environment from block zero's out-of-band data. The
2698 "nand env.oob" command can be used to record this offset.
2699 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
2700 using CONFIG_ENV_OFFSET_OOB.
2702 - CONFIG_NAND_ENV_DST
2704 Defines address in RAM to which the nand_spl code should copy the
2705 environment. If redundant environment is used, it will be copied to
2706 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
2708 - CONFIG_SYS_SPI_INIT_OFFSET
2710 Defines offset to the initial SPI buffer area in DPRAM. The
2711 area is used at an early stage (ROM part) if the environment
2712 is configured to reside in the SPI EEPROM: We need a 520 byte
2713 scratch DPRAM area. It is used between the two initialization
2714 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
2715 to be a good choice since it makes it far enough from the
2716 start of the data area as well as from the stack pointer.
2718 Please note that the environment is read-only until the monitor
2719 has been relocated to RAM and a RAM copy of the environment has been
2720 created; also, when using EEPROM you will have to use getenv_f()
2721 until then to read environment variables.
2723 The environment is protected by a CRC32 checksum. Before the monitor
2724 is relocated into RAM, as a result of a bad CRC you will be working
2725 with the compiled-in default environment - *silently*!!! [This is
2726 necessary, because the first environment variable we need is the
2727 "baudrate" setting for the console - if we have a bad CRC, we don't
2728 have any device yet where we could complain.]
2730 Note: once the monitor has been relocated, then it will complain if
2731 the default environment is used; a new CRC is computed as soon as you
2732 use the "saveenv" command to store a valid environment.
2734 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
2735 Echo the inverted Ethernet link state to the fault LED.
2737 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
2738 also needs to be defined.
2740 - CONFIG_SYS_FAULT_MII_ADDR:
2741 MII address of the PHY to check for the Ethernet link state.
2743 - CONFIG_NS16550_MIN_FUNCTIONS:
2744 Define this if you desire to only have use of the NS16550_init
2745 and NS16550_putc functions for the serial driver located at
2746 drivers/serial/ns16550.c. This option is useful for saving
2747 space for already greatly restricted images, including but not
2748 limited to NAND_SPL configurations.
2750 Low Level (hardware related) configuration options:
2751 ---------------------------------------------------
2753 - CONFIG_SYS_CACHELINE_SIZE:
2754 Cache Line Size of the CPU.
2756 - CONFIG_SYS_DEFAULT_IMMR:
2757 Default address of the IMMR after system reset.
2759 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
2760 and RPXsuper) to be able to adjust the position of
2761 the IMMR register after a reset.
2763 - Floppy Disk Support:
2764 CONFIG_SYS_FDC_DRIVE_NUMBER
2766 the default drive number (default value 0)
2768 CONFIG_SYS_ISA_IO_STRIDE
2770 defines the spacing between FDC chipset registers
2773 CONFIG_SYS_ISA_IO_OFFSET
2775 defines the offset of register from address. It
2776 depends on which part of the data bus is connected to
2777 the FDC chipset. (default value 0)
2779 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
2780 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
2783 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
2784 fdc_hw_init() is called at the beginning of the FDC
2785 setup. fdc_hw_init() must be provided by the board
2786 source code. It is used to make hardware dependant
2790 Most IDE controllers were designed to be connected with PCI
2791 interface. Only few of them were designed for AHB interface.
2792 When software is doing ATA command and data transfer to
2793 IDE devices through IDE-AHB controller, some additional
2794 registers accessing to these kind of IDE-AHB controller
2797 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
2798 DO NOT CHANGE unless you know exactly what you're
2799 doing! (11-4) [MPC8xx/82xx systems only]
2801 - CONFIG_SYS_INIT_RAM_ADDR:
2803 Start address of memory area that can be used for
2804 initial data and stack; please note that this must be
2805 writable memory that is working WITHOUT special
2806 initialization, i. e. you CANNOT use normal RAM which
2807 will become available only after programming the
2808 memory controller and running certain initialization
2811 U-Boot uses the following memory types:
2812 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
2813 - MPC824X: data cache
2814 - PPC4xx: data cache
2816 - CONFIG_SYS_GBL_DATA_OFFSET:
2818 Offset of the initial data structure in the memory
2819 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
2820 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
2821 data is located at the end of the available space
2822 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
2823 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
2824 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
2825 CONFIG_SYS_GBL_DATA_OFFSET) downward.
2828 On the MPC824X (or other systems that use the data
2829 cache for initial memory) the address chosen for
2830 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
2831 point to an otherwise UNUSED address space between
2832 the top of RAM and the start of the PCI space.
2834 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
2836 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
2838 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
2840 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
2842 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
2844 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
2846 - CONFIG_SYS_OR_TIMING_SDRAM:
2849 - CONFIG_SYS_MAMR_PTA:
2850 periodic timer for refresh
2852 - CONFIG_SYS_DER: Debug Event Register (37-47)
2854 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
2855 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
2856 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
2857 CONFIG_SYS_BR1_PRELIM:
2858 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
2860 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
2861 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
2862 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
2863 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
2865 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
2866 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
2867 Machine Mode Register and Memory Periodic Timer
2868 Prescaler definitions (SDRAM timing)
2870 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
2871 enable I2C microcode relocation patch (MPC8xx);
2872 define relocation offset in DPRAM [DSP2]
2874 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
2875 enable SMC microcode relocation patch (MPC8xx);
2876 define relocation offset in DPRAM [SMC1]
2878 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
2879 enable SPI microcode relocation patch (MPC8xx);
2880 define relocation offset in DPRAM [SCC4]
2882 - CONFIG_SYS_USE_OSCCLK:
2883 Use OSCM clock mode on MBX8xx board. Be careful,
2884 wrong setting might damage your board. Read
2885 doc/README.MBX before setting this variable!
2887 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
2888 Offset of the bootmode word in DPRAM used by post
2889 (Power On Self Tests). This definition overrides
2890 #define'd default value in commproc.h resp.
2893 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
2894 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
2895 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
2896 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
2897 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
2898 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
2899 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
2900 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
2901 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
2903 - CONFIG_PCI_DISABLE_PCIE:
2904 Disable PCI-Express on systems where it is supported but not
2908 Chip has SRIO or not
2911 Board has SRIO 1 port available
2914 Board has SRIO 2 port available
2916 - CONFIG_SYS_SRIOn_MEM_VIRT:
2917 Virtual Address of SRIO port 'n' memory region
2919 - CONFIG_SYS_SRIOn_MEM_PHYS:
2920 Physical Address of SRIO port 'n' memory region
2922 - CONFIG_SYS_SRIOn_MEM_SIZE:
2923 Size of SRIO port 'n' memory region
2925 - CONFIG_SYS_NDFC_16
2926 Defined to tell the NDFC that the NAND chip is using a
2929 - CONFIG_SYS_NDFC_EBC0_CFG
2930 Sets the EBC0_CFG register for the NDFC. If not defined
2931 a default value will be used.
2934 Get DDR timing information from an I2C EEPROM. Common
2935 with pluggable memory modules such as SODIMMs
2938 I2C address of the SPD EEPROM
2940 - CONFIG_SYS_SPD_BUS_NUM
2941 If SPD EEPROM is on an I2C bus other than the first
2942 one, specify here. Note that the value must resolve
2943 to something your driver can deal with.
2945 - CONFIG_SYS_83XX_DDR_USES_CS0
2946 Only for 83xx systems. If specified, then DDR should
2947 be configured using CS0 and CS1 instead of CS2 and CS3.
2949 - CONFIG_ETHER_ON_FEC[12]
2950 Define to enable FEC[12] on a 8xx series processor.
2952 - CONFIG_FEC[12]_PHY
2953 Define to the hardcoded PHY address which corresponds
2954 to the given FEC; i. e.
2955 #define CONFIG_FEC1_PHY 4
2956 means that the PHY with address 4 is connected to FEC1
2958 When set to -1, means to probe for first available.
2960 - CONFIG_FEC[12]_PHY_NORXERR
2961 The PHY does not have a RXERR line (RMII only).
2962 (so program the FEC to ignore it).
2965 Enable RMII mode for all FECs.
2966 Note that this is a global option, we can't
2967 have one FEC in standard MII mode and another in RMII mode.
2969 - CONFIG_CRC32_VERIFY
2970 Add a verify option to the crc32 command.
2973 => crc32 -v <address> <count> <crc32>
2975 Where address/count indicate a memory area
2976 and crc32 is the correct crc32 which the
2980 Add the "loopw" memory command. This only takes effect if
2981 the memory commands are activated globally (CONFIG_CMD_MEM).
2984 Add the "mdc" and "mwc" memory commands. These are cyclic
2989 This command will print 4 bytes (10,11,12,13) each 500 ms.
2991 => mwc.l 100 12345678 10
2992 This command will write 12345678 to address 100 all 10 ms.
2994 This only takes effect if the memory commands are activated
2995 globally (CONFIG_CMD_MEM).
2997 - CONFIG_SKIP_LOWLEVEL_INIT
2998 [ARM only] If this variable is defined, then certain
2999 low level initializations (like setting up the memory
3000 controller) are omitted and/or U-Boot does not
3001 relocate itself into RAM.
3003 Normally this variable MUST NOT be defined. The only
3004 exception is when U-Boot is loaded (to RAM) by some
3005 other boot loader or by a debugger which performs
3006 these initializations itself.
3009 Modifies the behaviour of start.S when compiling a loader
3010 that is executed before the actual U-Boot. E.g. when
3011 compiling a NAND SPL.
3013 - CONFIG_USE_ARCH_MEMCPY
3014 CONFIG_USE_ARCH_MEMSET
3015 If these options are used a optimized version of memcpy/memset will
3016 be used if available. These functions may be faster under some
3017 conditions but may increase the binary size.
3019 Building the Software:
3020 ======================
3022 Building U-Boot has been tested in several native build environments
3023 and in many different cross environments. Of course we cannot support
3024 all possibly existing versions of cross development tools in all
3025 (potentially obsolete) versions. In case of tool chain problems we
3026 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
3027 which is extensively used to build and test U-Boot.
3029 If you are not using a native environment, it is assumed that you
3030 have GNU cross compiling tools available in your path. In this case,
3031 you must set the environment variable CROSS_COMPILE in your shell.
3032 Note that no changes to the Makefile or any other source files are
3033 necessary. For example using the ELDK on a 4xx CPU, please enter:
3035 $ CROSS_COMPILE=ppc_4xx-
3036 $ export CROSS_COMPILE
3038 Note: If you wish to generate Windows versions of the utilities in
3039 the tools directory you can use the MinGW toolchain
3040 (http://www.mingw.org). Set your HOST tools to the MinGW
3041 toolchain and execute 'make tools'. For example:
3043 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
3045 Binaries such as tools/mkimage.exe will be created which can
3046 be executed on computers running Windows.
3048 U-Boot is intended to be simple to build. After installing the
3049 sources you must configure U-Boot for one specific board type. This
3054 where "NAME_config" is the name of one of the existing configu-
3055 rations; see the main Makefile for supported names.
3057 Note: for some board special configuration names may exist; check if
3058 additional information is available from the board vendor; for
3059 instance, the TQM823L systems are available without (standard)
3060 or with LCD support. You can select such additional "features"
3061 when choosing the configuration, i. e.
3064 - will configure for a plain TQM823L, i. e. no LCD support
3066 make TQM823L_LCD_config
3067 - will configure for a TQM823L with U-Boot console on LCD
3072 Finally, type "make all", and you should get some working U-Boot
3073 images ready for download to / installation on your system:
3075 - "u-boot.bin" is a raw binary image
3076 - "u-boot" is an image in ELF binary format
3077 - "u-boot.srec" is in Motorola S-Record format
3079 By default the build is performed locally and the objects are saved
3080 in the source directory. One of the two methods can be used to change
3081 this behavior and build U-Boot to some external directory:
3083 1. Add O= to the make command line invocations:
3085 make O=/tmp/build distclean
3086 make O=/tmp/build NAME_config
3087 make O=/tmp/build all
3089 2. Set environment variable BUILD_DIR to point to the desired location:
3091 export BUILD_DIR=/tmp/build
3096 Note that the command line "O=" setting overrides the BUILD_DIR environment
3100 Please be aware that the Makefiles assume you are using GNU make, so
3101 for instance on NetBSD you might need to use "gmake" instead of
3105 If the system board that you have is not listed, then you will need
3106 to port U-Boot to your hardware platform. To do this, follow these
3109 1. Add a new configuration option for your board to the toplevel
3110 "Makefile" and to the "MAKEALL" script, using the existing
3111 entries as examples. Note that here and at many other places
3112 boards and other names are listed in alphabetical sort order. Please
3114 2. Create a new directory to hold your board specific code. Add any
3115 files you need. In your board directory, you will need at least
3116 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
3117 3. Create a new configuration file "include/configs/<board>.h" for
3119 3. If you're porting U-Boot to a new CPU, then also create a new
3120 directory to hold your CPU specific code. Add any files you need.
3121 4. Run "make <board>_config" with your new name.
3122 5. Type "make", and you should get a working "u-boot.srec" file
3123 to be installed on your target system.
3124 6. Debug and solve any problems that might arise.
3125 [Of course, this last step is much harder than it sounds.]
3128 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
3129 ==============================================================
3131 If you have modified U-Boot sources (for instance added a new board
3132 or support for new devices, a new CPU, etc.) you are expected to
3133 provide feedback to the other developers. The feedback normally takes
3134 the form of a "patch", i. e. a context diff against a certain (latest
3135 official or latest in the git repository) version of U-Boot sources.
3137 But before you submit such a patch, please verify that your modifi-
3138 cation did not break existing code. At least make sure that *ALL* of
3139 the supported boards compile WITHOUT ANY compiler warnings. To do so,
3140 just run the "MAKEALL" script, which will configure and build U-Boot
3141 for ALL supported system. Be warned, this will take a while. You can
3142 select which (cross) compiler to use by passing a `CROSS_COMPILE'
3143 environment variable to the script, i. e. to use the ELDK cross tools
3146 CROSS_COMPILE=ppc_8xx- MAKEALL
3148 or to build on a native PowerPC system you can type
3150 CROSS_COMPILE=' ' MAKEALL
3152 When using the MAKEALL script, the default behaviour is to build
3153 U-Boot in the source directory. This location can be changed by
3154 setting the BUILD_DIR environment variable. Also, for each target
3155 built, the MAKEALL script saves two log files (<target>.ERR and
3156 <target>.MAKEALL) in the <source dir>/LOG directory. This default
3157 location can be changed by setting the MAKEALL_LOGDIR environment
3158 variable. For example:
3160 export BUILD_DIR=/tmp/build
3161 export MAKEALL_LOGDIR=/tmp/log
3162 CROSS_COMPILE=ppc_8xx- MAKEALL
3164 With the above settings build objects are saved in the /tmp/build,
3165 log files are saved in the /tmp/log and the source tree remains clean
3166 during the whole build process.
3169 See also "U-Boot Porting Guide" below.
3172 Monitor Commands - Overview:
3173 ============================
3175 go - start application at address 'addr'
3176 run - run commands in an environment variable
3177 bootm - boot application image from memory
3178 bootp - boot image via network using BootP/TFTP protocol
3179 tftpboot- boot image via network using TFTP protocol
3180 and env variables "ipaddr" and "serverip"
3181 (and eventually "gatewayip")
3182 rarpboot- boot image via network using RARP/TFTP protocol
3183 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
3184 loads - load S-Record file over serial line
3185 loadb - load binary file over serial line (kermit mode)
3187 mm - memory modify (auto-incrementing)
3188 nm - memory modify (constant address)
3189 mw - memory write (fill)
3191 cmp - memory compare
3192 crc32 - checksum calculation
3193 i2c - I2C sub-system
3194 sspi - SPI utility commands
3195 base - print or set address offset
3196 printenv- print environment variables
3197 setenv - set environment variables
3198 saveenv - save environment variables to persistent storage
3199 protect - enable or disable FLASH write protection
3200 erase - erase FLASH memory
3201 flinfo - print FLASH memory information
3202 bdinfo - print Board Info structure
3203 iminfo - print header information for application image
3204 coninfo - print console devices and informations
3205 ide - IDE sub-system
3206 loop - infinite loop on address range
3207 loopw - infinite write loop on address range
3208 mtest - simple RAM test
3209 icache - enable or disable instruction cache
3210 dcache - enable or disable data cache
3211 reset - Perform RESET of the CPU
3212 echo - echo args to console
3213 version - print monitor version
3214 help - print online help
3215 ? - alias for 'help'
3218 Monitor Commands - Detailed Description:
3219 ========================================
3223 For now: just type "help <command>".
3226 Environment Variables:
3227 ======================
3229 U-Boot supports user configuration using Environment Variables which
3230 can be made persistent by saving to Flash memory.
3232 Environment Variables are set using "setenv", printed using
3233 "printenv", and saved to Flash using "saveenv". Using "setenv"
3234 without a value can be used to delete a variable from the
3235 environment. As long as you don't save the environment you are
3236 working with an in-memory copy. In case the Flash area containing the
3237 environment is erased by accident, a default environment is provided.
3239 Some configuration options can be set using Environment Variables.
3241 List of environment variables (most likely not complete):
3243 baudrate - see CONFIG_BAUDRATE
3245 bootdelay - see CONFIG_BOOTDELAY
3247 bootcmd - see CONFIG_BOOTCOMMAND
3249 bootargs - Boot arguments when booting an RTOS image
3251 bootfile - Name of the image to load with TFTP
3253 bootm_low - Memory range available for image processing in the bootm
3254 command can be restricted. This variable is given as
3255 a hexadecimal number and defines lowest address allowed
3256 for use by the bootm command. See also "bootm_size"
3257 environment variable. Address defined by "bootm_low" is
3258 also the base of the initial memory mapping for the Linux
3259 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
3262 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
3263 This variable is given as a hexadecimal number and it
3264 defines the size of the memory region starting at base
3265 address bootm_low that is accessible by the Linux kernel
3266 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
3267 as the default value if it is defined, and bootm_size is
3270 bootm_size - Memory range available for image processing in the bootm
3271 command can be restricted. This variable is given as
3272 a hexadecimal number and defines the size of the region
3273 allowed for use by the bootm command. See also "bootm_low"
3274 environment variable.
3276 updatefile - Location of the software update file on a TFTP server, used
3277 by the automatic software update feature. Please refer to
3278 documentation in doc/README.update for more details.
3280 autoload - if set to "no" (any string beginning with 'n'),
3281 "bootp" will just load perform a lookup of the
3282 configuration from the BOOTP server, but not try to
3283 load any image using TFTP
3285 autostart - if set to "yes", an image loaded using the "bootp",
3286 "rarpboot", "tftpboot" or "diskboot" commands will
3287 be automatically started (by internally calling
3290 If set to "no", a standalone image passed to the
3291 "bootm" command will be copied to the load address
3292 (and eventually uncompressed), but NOT be started.
3293 This can be used to load and uncompress arbitrary
3296 i2cfast - (PPC405GP|PPC405EP only)
3297 if set to 'y' configures Linux I2C driver for fast
3298 mode (400kHZ). This environment variable is used in
3299 initialization code. So, for changes to be effective
3300 it must be saved and board must be reset.
3302 initrd_high - restrict positioning of initrd images:
3303 If this variable is not set, initrd images will be
3304 copied to the highest possible address in RAM; this
3305 is usually what you want since it allows for
3306 maximum initrd size. If for some reason you want to
3307 make sure that the initrd image is loaded below the
3308 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
3309 variable to a value of "no" or "off" or "0".
3310 Alternatively, you can set it to a maximum upper
3311 address to use (U-Boot will still check that it
3312 does not overwrite the U-Boot stack and data).
3314 For instance, when you have a system with 16 MB
3315 RAM, and want to reserve 4 MB from use by Linux,
3316 you can do this by adding "mem=12M" to the value of
3317 the "bootargs" variable. However, now you must make
3318 sure that the initrd image is placed in the first
3319 12 MB as well - this can be done with
3321 setenv initrd_high 00c00000
3323 If you set initrd_high to 0xFFFFFFFF, this is an
3324 indication to U-Boot that all addresses are legal
3325 for the Linux kernel, including addresses in flash
3326 memory. In this case U-Boot will NOT COPY the
3327 ramdisk at all. This may be useful to reduce the
3328 boot time on your system, but requires that this
3329 feature is supported by your Linux kernel.
3331 ipaddr - IP address; needed for tftpboot command
3333 loadaddr - Default load address for commands like "bootp",
3334 "rarpboot", "tftpboot", "loadb" or "diskboot"
3336 loads_echo - see CONFIG_LOADS_ECHO
3338 serverip - TFTP server IP address; needed for tftpboot command
3340 bootretry - see CONFIG_BOOT_RETRY_TIME
3342 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
3344 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
3346 ethprime - When CONFIG_NET_MULTI is enabled controls which
3347 interface is used first.
3349 ethact - When CONFIG_NET_MULTI is enabled controls which
3350 interface is currently active. For example you
3351 can do the following
3353 => setenv ethact FEC
3354 => ping 192.168.0.1 # traffic sent on FEC
3355 => setenv ethact SCC
3356 => ping 10.0.0.1 # traffic sent on SCC
3358 ethrotate - When set to "no" U-Boot does not go through all
3359 available network interfaces.
3360 It just stays at the currently selected interface.
3362 netretry - When set to "no" each network operation will
3363 either succeed or fail without retrying.
3364 When set to "once" the network operation will
3365 fail when all the available network interfaces
3366 are tried once without success.
3367 Useful on scripts which control the retry operation
3370 npe_ucode - set load address for the NPE microcode
3372 tftpsrcport - If this is set, the value is used for TFTP's
3375 tftpdstport - If this is set, the value is used for TFTP's UDP
3376 destination port instead of the Well Know Port 69.
3378 tftpblocksize - Block size to use for TFTP transfers; if not set,
3379 we use the TFTP server's default block size
3381 tftptimeout - Retransmission timeout for TFTP packets (in milli-
3382 seconds, minimum value is 1000 = 1 second). Defines
3383 when a packet is considered to be lost so it has to
3384 be retransmitted. The default is 5000 = 5 seconds.
3385 Lowering this value may make downloads succeed
3386 faster in networks with high packet loss rates or
3387 with unreliable TFTP servers.
3389 vlan - When set to a value < 4095 the traffic over
3390 Ethernet is encapsulated/received over 802.1q
3393 The following environment variables may be used and automatically
3394 updated by the network boot commands ("bootp" and "rarpboot"),
3395 depending the information provided by your boot server:
3397 bootfile - see above
3398 dnsip - IP address of your Domain Name Server
3399 dnsip2 - IP address of your secondary Domain Name Server
3400 gatewayip - IP address of the Gateway (Router) to use
3401 hostname - Target hostname
3403 netmask - Subnet Mask
3404 rootpath - Pathname of the root filesystem on the NFS server
3405 serverip - see above
3408 There are two special Environment Variables:
3410 serial# - contains hardware identification information such
3411 as type string and/or serial number
3412 ethaddr - Ethernet address
3414 These variables can be set only once (usually during manufacturing of
3415 the board). U-Boot refuses to delete or overwrite these variables
3416 once they have been set once.
3419 Further special Environment Variables:
3421 ver - Contains the U-Boot version string as printed
3422 with the "version" command. This variable is
3423 readonly (see CONFIG_VERSION_VARIABLE).
3426 Please note that changes to some configuration parameters may take
3427 only effect after the next boot (yes, that's just like Windoze :-).
3430 Command Line Parsing:
3431 =====================
3433 There are two different command line parsers available with U-Boot:
3434 the old "simple" one, and the much more powerful "hush" shell:
3436 Old, simple command line parser:
3437 --------------------------------
3439 - supports environment variables (through setenv / saveenv commands)
3440 - several commands on one line, separated by ';'
3441 - variable substitution using "... ${name} ..." syntax
3442 - special characters ('$', ';') can be escaped by prefixing with '\',
3444 setenv bootcmd bootm \${address}
3445 - You can also escape text by enclosing in single apostrophes, for example:
3446 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
3451 - similar to Bourne shell, with control structures like
3452 if...then...else...fi, for...do...done; while...do...done,
3453 until...do...done, ...
3454 - supports environment ("global") variables (through setenv / saveenv
3455 commands) and local shell variables (through standard shell syntax
3456 "name=value"); only environment variables can be used with "run"
3462 (1) If a command line (or an environment variable executed by a "run"
3463 command) contains several commands separated by semicolon, and
3464 one of these commands fails, then the remaining commands will be
3467 (2) If you execute several variables with one call to run (i. e.
3468 calling run with a list of variables as arguments), any failing
3469 command will cause "run" to terminate, i. e. the remaining
3470 variables are not executed.
3472 Note for Redundant Ethernet Interfaces:
3473 =======================================
3475 Some boards come with redundant Ethernet interfaces; U-Boot supports
3476 such configurations and is capable of automatic selection of a
3477 "working" interface when needed. MAC assignment works as follows:
3479 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
3480 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
3481 "eth1addr" (=>eth1), "eth2addr", ...
3483 If the network interface stores some valid MAC address (for instance
3484 in SROM), this is used as default address if there is NO correspon-
3485 ding setting in the environment; if the corresponding environment
3486 variable is set, this overrides the settings in the card; that means:
3488 o If the SROM has a valid MAC address, and there is no address in the
3489 environment, the SROM's address is used.
3491 o If there is no valid address in the SROM, and a definition in the
3492 environment exists, then the value from the environment variable is
3495 o If both the SROM and the environment contain a MAC address, and
3496 both addresses are the same, this MAC address is used.
3498 o If both the SROM and the environment contain a MAC address, and the
3499 addresses differ, the value from the environment is used and a
3502 o If neither SROM nor the environment contain a MAC address, an error
3505 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
3506 will be programmed into hardware as part of the initialization process. This
3507 may be skipped by setting the appropriate 'ethmacskip' environment variable.
3508 The naming convention is as follows:
3509 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
3514 U-Boot is capable of booting (and performing other auxiliary operations on)
3515 images in two formats:
3517 New uImage format (FIT)
3518 -----------------------
3520 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
3521 to Flattened Device Tree). It allows the use of images with multiple
3522 components (several kernels, ramdisks, etc.), with contents protected by
3523 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
3529 Old image format is based on binary files which can be basically anything,
3530 preceded by a special header; see the definitions in include/image.h for
3531 details; basically, the header defines the following image properties:
3533 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
3534 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
3535 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
3536 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
3538 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
3539 IA64, MIPS, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
3540 Currently supported: ARM, AVR32, Intel x86, MIPS, Nios II, PowerPC).
3541 * Compression Type (uncompressed, gzip, bzip2)
3547 The header is marked by a special Magic Number, and both the header
3548 and the data portions of the image are secured against corruption by
3555 Although U-Boot should support any OS or standalone application
3556 easily, the main focus has always been on Linux during the design of
3559 U-Boot includes many features that so far have been part of some
3560 special "boot loader" code within the Linux kernel. Also, any
3561 "initrd" images to be used are no longer part of one big Linux image;
3562 instead, kernel and "initrd" are separate images. This implementation
3563 serves several purposes:
3565 - the same features can be used for other OS or standalone
3566 applications (for instance: using compressed images to reduce the
3567 Flash memory footprint)
3569 - it becomes much easier to port new Linux kernel versions because
3570 lots of low-level, hardware dependent stuff are done by U-Boot
3572 - the same Linux kernel image can now be used with different "initrd"
3573 images; of course this also means that different kernel images can
3574 be run with the same "initrd". This makes testing easier (you don't
3575 have to build a new "zImage.initrd" Linux image when you just
3576 change a file in your "initrd"). Also, a field-upgrade of the
3577 software is easier now.
3583 Porting Linux to U-Boot based systems:
3584 ---------------------------------------
3586 U-Boot cannot save you from doing all the necessary modifications to
3587 configure the Linux device drivers for use with your target hardware
3588 (no, we don't intend to provide a full virtual machine interface to
3591 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
3593 Just make sure your machine specific header file (for instance
3594 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
3595 Information structure as we define in include/asm-<arch>/u-boot.h,
3596 and make sure that your definition of IMAP_ADDR uses the same value
3597 as your U-Boot configuration in CONFIG_SYS_IMMR.
3600 Configuring the Linux kernel:
3601 -----------------------------
3603 No specific requirements for U-Boot. Make sure you have some root
3604 device (initial ramdisk, NFS) for your target system.
3607 Building a Linux Image:
3608 -----------------------
3610 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
3611 not used. If you use recent kernel source, a new build target
3612 "uImage" will exist which automatically builds an image usable by
3613 U-Boot. Most older kernels also have support for a "pImage" target,
3614 which was introduced for our predecessor project PPCBoot and uses a
3615 100% compatible format.
3624 The "uImage" build target uses a special tool (in 'tools/mkimage') to
3625 encapsulate a compressed Linux kernel image with header information,
3626 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
3628 * build a standard "vmlinux" kernel image (in ELF binary format):
3630 * convert the kernel into a raw binary image:
3632 ${CROSS_COMPILE}-objcopy -O binary \
3633 -R .note -R .comment \
3634 -S vmlinux linux.bin
3636 * compress the binary image:
3640 * package compressed binary image for U-Boot:
3642 mkimage -A ppc -O linux -T kernel -C gzip \
3643 -a 0 -e 0 -n "Linux Kernel Image" \
3644 -d linux.bin.gz uImage
3647 The "mkimage" tool can also be used to create ramdisk images for use
3648 with U-Boot, either separated from the Linux kernel image, or
3649 combined into one file. "mkimage" encapsulates the images with a 64
3650 byte header containing information about target architecture,
3651 operating system, image type, compression method, entry points, time
3652 stamp, CRC32 checksums, etc.
3654 "mkimage" can be called in two ways: to verify existing images and
3655 print the header information, or to build new images.
3657 In the first form (with "-l" option) mkimage lists the information
3658 contained in the header of an existing U-Boot image; this includes
3659 checksum verification:
3661 tools/mkimage -l image
3662 -l ==> list image header information
3664 The second form (with "-d" option) is used to build a U-Boot image
3665 from a "data file" which is used as image payload:
3667 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
3668 -n name -d data_file image
3669 -A ==> set architecture to 'arch'
3670 -O ==> set operating system to 'os'
3671 -T ==> set image type to 'type'
3672 -C ==> set compression type 'comp'
3673 -a ==> set load address to 'addr' (hex)
3674 -e ==> set entry point to 'ep' (hex)
3675 -n ==> set image name to 'name'
3676 -d ==> use image data from 'datafile'
3678 Right now, all Linux kernels for PowerPC systems use the same load
3679 address (0x00000000), but the entry point address depends on the
3682 - 2.2.x kernels have the entry point at 0x0000000C,
3683 - 2.3.x and later kernels have the entry point at 0x00000000.
3685 So a typical call to build a U-Boot image would read:
3687 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3688 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
3689 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
3690 > examples/uImage.TQM850L
3691 Image Name: 2.4.4 kernel for TQM850L
3692 Created: Wed Jul 19 02:34:59 2000
3693 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3694 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3695 Load Address: 0x00000000
3696 Entry Point: 0x00000000
3698 To verify the contents of the image (or check for corruption):
3700 -> tools/mkimage -l examples/uImage.TQM850L
3701 Image Name: 2.4.4 kernel for TQM850L
3702 Created: Wed Jul 19 02:34:59 2000
3703 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3704 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3705 Load Address: 0x00000000
3706 Entry Point: 0x00000000
3708 NOTE: for embedded systems where boot time is critical you can trade
3709 speed for memory and install an UNCOMPRESSED image instead: this
3710 needs more space in Flash, but boots much faster since it does not
3711 need to be uncompressed:
3713 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
3714 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3715 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
3716 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
3717 > examples/uImage.TQM850L-uncompressed
3718 Image Name: 2.4.4 kernel for TQM850L
3719 Created: Wed Jul 19 02:34:59 2000
3720 Image Type: PowerPC Linux Kernel Image (uncompressed)
3721 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
3722 Load Address: 0x00000000
3723 Entry Point: 0x00000000
3726 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
3727 when your kernel is intended to use an initial ramdisk:
3729 -> tools/mkimage -n 'Simple Ramdisk Image' \
3730 > -A ppc -O linux -T ramdisk -C gzip \
3731 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
3732 Image Name: Simple Ramdisk Image
3733 Created: Wed Jan 12 14:01:50 2000
3734 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3735 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
3736 Load Address: 0x00000000
3737 Entry Point: 0x00000000
3740 Installing a Linux Image:
3741 -------------------------
3743 To downloading a U-Boot image over the serial (console) interface,
3744 you must convert the image to S-Record format:
3746 objcopy -I binary -O srec examples/image examples/image.srec
3748 The 'objcopy' does not understand the information in the U-Boot
3749 image header, so the resulting S-Record file will be relative to
3750 address 0x00000000. To load it to a given address, you need to
3751 specify the target address as 'offset' parameter with the 'loads'
3754 Example: install the image to address 0x40100000 (which on the
3755 TQM8xxL is in the first Flash bank):
3757 => erase 40100000 401FFFFF
3763 ## Ready for S-Record download ...
3764 ~>examples/image.srec
3765 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
3767 15989 15990 15991 15992
3768 [file transfer complete]
3770 ## Start Addr = 0x00000000
3773 You can check the success of the download using the 'iminfo' command;
3774 this includes a checksum verification so you can be sure no data
3775 corruption happened:
3779 ## Checking Image at 40100000 ...
3780 Image Name: 2.2.13 for initrd on TQM850L
3781 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3782 Data Size: 335725 Bytes = 327 kB = 0 MB
3783 Load Address: 00000000
3784 Entry Point: 0000000c
3785 Verifying Checksum ... OK
3791 The "bootm" command is used to boot an application that is stored in
3792 memory (RAM or Flash). In case of a Linux kernel image, the contents
3793 of the "bootargs" environment variable is passed to the kernel as
3794 parameters. You can check and modify this variable using the
3795 "printenv" and "setenv" commands:
3798 => printenv bootargs
3799 bootargs=root=/dev/ram
3801 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3803 => printenv bootargs
3804 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3807 ## Booting Linux kernel at 40020000 ...
3808 Image Name: 2.2.13 for NFS on TQM850L
3809 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3810 Data Size: 381681 Bytes = 372 kB = 0 MB
3811 Load Address: 00000000
3812 Entry Point: 0000000c
3813 Verifying Checksum ... OK
3814 Uncompressing Kernel Image ... OK
3815 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
3816 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3817 time_init: decrementer frequency = 187500000/60
3818 Calibrating delay loop... 49.77 BogoMIPS
3819 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
3822 If you want to boot a Linux kernel with initial RAM disk, you pass
3823 the memory addresses of both the kernel and the initrd image (PPBCOOT
3824 format!) to the "bootm" command:
3826 => imi 40100000 40200000
3828 ## Checking Image at 40100000 ...
3829 Image Name: 2.2.13 for initrd on TQM850L
3830 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3831 Data Size: 335725 Bytes = 327 kB = 0 MB
3832 Load Address: 00000000
3833 Entry Point: 0000000c
3834 Verifying Checksum ... OK
3836 ## Checking Image at 40200000 ...
3837 Image Name: Simple Ramdisk Image
3838 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3839 Data Size: 566530 Bytes = 553 kB = 0 MB
3840 Load Address: 00000000
3841 Entry Point: 00000000
3842 Verifying Checksum ... OK
3844 => bootm 40100000 40200000
3845 ## Booting Linux kernel at 40100000 ...
3846 Image Name: 2.2.13 for initrd on TQM850L
3847 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3848 Data Size: 335725 Bytes = 327 kB = 0 MB
3849 Load Address: 00000000
3850 Entry Point: 0000000c
3851 Verifying Checksum ... OK
3852 Uncompressing Kernel Image ... OK
3853 ## Loading RAMDisk Image at 40200000 ...
3854 Image Name: Simple Ramdisk Image
3855 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3856 Data Size: 566530 Bytes = 553 kB = 0 MB
3857 Load Address: 00000000
3858 Entry Point: 00000000
3859 Verifying Checksum ... OK
3860 Loading Ramdisk ... OK
3861 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
3862 Boot arguments: root=/dev/ram
3863 time_init: decrementer frequency = 187500000/60
3864 Calibrating delay loop... 49.77 BogoMIPS
3866 RAMDISK: Compressed image found at block 0
3867 VFS: Mounted root (ext2 filesystem).
3871 Boot Linux and pass a flat device tree:
3874 First, U-Boot must be compiled with the appropriate defines. See the section
3875 titled "Linux Kernel Interface" above for a more in depth explanation. The
3876 following is an example of how to start a kernel and pass an updated
3882 oft=oftrees/mpc8540ads.dtb
3883 => tftp $oftaddr $oft
3884 Speed: 1000, full duplex
3886 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
3887 Filename 'oftrees/mpc8540ads.dtb'.
3888 Load address: 0x300000
3891 Bytes transferred = 4106 (100a hex)
3892 => tftp $loadaddr $bootfile
3893 Speed: 1000, full duplex
3895 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
3897 Load address: 0x200000
3898 Loading:############
3900 Bytes transferred = 1029407 (fb51f hex)
3905 => bootm $loadaddr - $oftaddr
3906 ## Booting image at 00200000 ...
3907 Image Name: Linux-2.6.17-dirty
3908 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3909 Data Size: 1029343 Bytes = 1005.2 kB
3910 Load Address: 00000000
3911 Entry Point: 00000000
3912 Verifying Checksum ... OK
3913 Uncompressing Kernel Image ... OK
3914 Booting using flat device tree at 0x300000
3915 Using MPC85xx ADS machine description
3916 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
3920 More About U-Boot Image Types:
3921 ------------------------------
3923 U-Boot supports the following image types:
3925 "Standalone Programs" are directly runnable in the environment
3926 provided by U-Boot; it is expected that (if they behave
3927 well) you can continue to work in U-Boot after return from
3928 the Standalone Program.
3929 "OS Kernel Images" are usually images of some Embedded OS which
3930 will take over control completely. Usually these programs
3931 will install their own set of exception handlers, device
3932 drivers, set up the MMU, etc. - this means, that you cannot
3933 expect to re-enter U-Boot except by resetting the CPU.
3934 "RAMDisk Images" are more or less just data blocks, and their
3935 parameters (address, size) are passed to an OS kernel that is
3937 "Multi-File Images" contain several images, typically an OS
3938 (Linux) kernel image and one or more data images like
3939 RAMDisks. This construct is useful for instance when you want
3940 to boot over the network using BOOTP etc., where the boot
3941 server provides just a single image file, but you want to get
3942 for instance an OS kernel and a RAMDisk image.
3944 "Multi-File Images" start with a list of image sizes, each
3945 image size (in bytes) specified by an "uint32_t" in network
3946 byte order. This list is terminated by an "(uint32_t)0".
3947 Immediately after the terminating 0 follow the images, one by
3948 one, all aligned on "uint32_t" boundaries (size rounded up to
3949 a multiple of 4 bytes).
3951 "Firmware Images" are binary images containing firmware (like
3952 U-Boot or FPGA images) which usually will be programmed to
3955 "Script files" are command sequences that will be executed by
3956 U-Boot's command interpreter; this feature is especially
3957 useful when you configure U-Boot to use a real shell (hush)
3958 as command interpreter.
3964 One of the features of U-Boot is that you can dynamically load and
3965 run "standalone" applications, which can use some resources of
3966 U-Boot like console I/O functions or interrupt services.
3968 Two simple examples are included with the sources:
3973 'examples/hello_world.c' contains a small "Hello World" Demo
3974 application; it is automatically compiled when you build U-Boot.
3975 It's configured to run at address 0x00040004, so you can play with it
3979 ## Ready for S-Record download ...
3980 ~>examples/hello_world.srec
3981 1 2 3 4 5 6 7 8 9 10 11 ...
3982 [file transfer complete]
3984 ## Start Addr = 0x00040004
3986 => go 40004 Hello World! This is a test.
3987 ## Starting application at 0x00040004 ...
3998 Hit any key to exit ...
4000 ## Application terminated, rc = 0x0
4002 Another example, which demonstrates how to register a CPM interrupt
4003 handler with the U-Boot code, can be found in 'examples/timer.c'.
4004 Here, a CPM timer is set up to generate an interrupt every second.
4005 The interrupt service routine is trivial, just printing a '.'
4006 character, but this is just a demo program. The application can be
4007 controlled by the following keys:
4009 ? - print current values og the CPM Timer registers
4010 b - enable interrupts and start timer
4011 e - stop timer and disable interrupts
4012 q - quit application
4015 ## Ready for S-Record download ...
4016 ~>examples/timer.srec
4017 1 2 3 4 5 6 7 8 9 10 11 ...
4018 [file transfer complete]
4020 ## Start Addr = 0x00040004
4023 ## Starting application at 0x00040004 ...
4026 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
4029 [q, b, e, ?] Set interval 1000000 us
4032 [q, b, e, ?] ........
4033 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
4036 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
4039 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
4042 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
4044 [q, b, e, ?] ...Stopping timer
4046 [q, b, e, ?] ## Application terminated, rc = 0x0
4052 Over time, many people have reported problems when trying to use the
4053 "minicom" terminal emulation program for serial download. I (wd)
4054 consider minicom to be broken, and recommend not to use it. Under
4055 Unix, I recommend to use C-Kermit for general purpose use (and
4056 especially for kermit binary protocol download ("loadb" command), and
4057 use "cu" for S-Record download ("loads" command).
4059 Nevertheless, if you absolutely want to use it try adding this
4060 configuration to your "File transfer protocols" section:
4062 Name Program Name U/D FullScr IO-Red. Multi
4063 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
4064 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
4070 Starting at version 0.9.2, U-Boot supports NetBSD both as host
4071 (build U-Boot) and target system (boots NetBSD/mpc8xx).
4073 Building requires a cross environment; it is known to work on
4074 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
4075 need gmake since the Makefiles are not compatible with BSD make).
4076 Note that the cross-powerpc package does not install include files;
4077 attempting to build U-Boot will fail because <machine/ansi.h> is
4078 missing. This file has to be installed and patched manually:
4080 # cd /usr/pkg/cross/powerpc-netbsd/include
4082 # ln -s powerpc machine
4083 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
4084 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
4086 Native builds *don't* work due to incompatibilities between native
4087 and U-Boot include files.
4089 Booting assumes that (the first part of) the image booted is a
4090 stage-2 loader which in turn loads and then invokes the kernel
4091 proper. Loader sources will eventually appear in the NetBSD source
4092 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
4093 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
4096 Implementation Internals:
4097 =========================
4099 The following is not intended to be a complete description of every
4100 implementation detail. However, it should help to understand the
4101 inner workings of U-Boot and make it easier to port it to custom
4105 Initial Stack, Global Data:
4106 ---------------------------
4108 The implementation of U-Boot is complicated by the fact that U-Boot
4109 starts running out of ROM (flash memory), usually without access to
4110 system RAM (because the memory controller is not initialized yet).
4111 This means that we don't have writable Data or BSS segments, and BSS
4112 is not initialized as zero. To be able to get a C environment working
4113 at all, we have to allocate at least a minimal stack. Implementation
4114 options for this are defined and restricted by the CPU used: Some CPU
4115 models provide on-chip memory (like the IMMR area on MPC8xx and
4116 MPC826x processors), on others (parts of) the data cache can be
4117 locked as (mis-) used as memory, etc.
4119 Chris Hallinan posted a good summary of these issues to the
4120 U-Boot mailing list:
4122 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
4123 From: "Chris Hallinan" <clh@net1plus.com>
4124 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
4127 Correct me if I'm wrong, folks, but the way I understand it
4128 is this: Using DCACHE as initial RAM for Stack, etc, does not
4129 require any physical RAM backing up the cache. The cleverness
4130 is that the cache is being used as a temporary supply of
4131 necessary storage before the SDRAM controller is setup. It's
4132 beyond the scope of this list to explain the details, but you
4133 can see how this works by studying the cache architecture and
4134 operation in the architecture and processor-specific manuals.
4136 OCM is On Chip Memory, which I believe the 405GP has 4K. It
4137 is another option for the system designer to use as an
4138 initial stack/RAM area prior to SDRAM being available. Either
4139 option should work for you. Using CS 4 should be fine if your
4140 board designers haven't used it for something that would
4141 cause you grief during the initial boot! It is frequently not
4144 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
4145 with your processor/board/system design. The default value
4146 you will find in any recent u-boot distribution in
4147 walnut.h should work for you. I'd set it to a value larger
4148 than your SDRAM module. If you have a 64MB SDRAM module, set
4149 it above 400_0000. Just make sure your board has no resources
4150 that are supposed to respond to that address! That code in
4151 start.S has been around a while and should work as is when
4152 you get the config right.
4157 It is essential to remember this, since it has some impact on the C
4158 code for the initialization procedures:
4160 * Initialized global data (data segment) is read-only. Do not attempt
4163 * Do not use any uninitialized global data (or implicitely initialized
4164 as zero data - BSS segment) at all - this is undefined, initiali-
4165 zation is performed later (when relocating to RAM).
4167 * Stack space is very limited. Avoid big data buffers or things like
4170 Having only the stack as writable memory limits means we cannot use
4171 normal global data to share information beween the code. But it
4172 turned out that the implementation of U-Boot can be greatly
4173 simplified by making a global data structure (gd_t) available to all
4174 functions. We could pass a pointer to this data as argument to _all_
4175 functions, but this would bloat the code. Instead we use a feature of
4176 the GCC compiler (Global Register Variables) to share the data: we
4177 place a pointer (gd) to the global data into a register which we
4178 reserve for this purpose.
4180 When choosing a register for such a purpose we are restricted by the
4181 relevant (E)ABI specifications for the current architecture, and by
4182 GCC's implementation.
4184 For PowerPC, the following registers have specific use:
4186 R2: reserved for system use
4187 R3-R4: parameter passing and return values
4188 R5-R10: parameter passing
4189 R13: small data area pointer
4193 (U-Boot also uses R12 as internal GOT pointer. r12
4194 is a volatile register so r12 needs to be reset when
4195 going back and forth between asm and C)
4197 ==> U-Boot will use R2 to hold a pointer to the global data
4199 Note: on PPC, we could use a static initializer (since the
4200 address of the global data structure is known at compile time),
4201 but it turned out that reserving a register results in somewhat
4202 smaller code - although the code savings are not that big (on
4203 average for all boards 752 bytes for the whole U-Boot image,
4204 624 text + 127 data).
4206 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
4207 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
4209 ==> U-Boot will use P3 to hold a pointer to the global data
4211 On ARM, the following registers are used:
4213 R0: function argument word/integer result
4214 R1-R3: function argument word
4216 R10: stack limit (used only if stack checking if enabled)
4217 R11: argument (frame) pointer
4218 R12: temporary workspace
4221 R15: program counter
4223 ==> U-Boot will use R8 to hold a pointer to the global data
4225 On Nios II, the ABI is documented here:
4226 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
4228 ==> U-Boot will use gp to hold a pointer to the global data
4230 Note: on Nios II, we give "-G0" option to gcc and don't use gp
4231 to access small data sections, so gp is free.
4233 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
4234 or current versions of GCC may "optimize" the code too much.
4239 U-Boot runs in system state and uses physical addresses, i.e. the
4240 MMU is not used either for address mapping nor for memory protection.
4242 The available memory is mapped to fixed addresses using the memory
4243 controller. In this process, a contiguous block is formed for each
4244 memory type (Flash, SDRAM, SRAM), even when it consists of several
4245 physical memory banks.
4247 U-Boot is installed in the first 128 kB of the first Flash bank (on
4248 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
4249 booting and sizing and initializing DRAM, the code relocates itself
4250 to the upper end of DRAM. Immediately below the U-Boot code some
4251 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
4252 configuration setting]. Below that, a structure with global Board
4253 Info data is placed, followed by the stack (growing downward).
4255 Additionally, some exception handler code is copied to the low 8 kB
4256 of DRAM (0x00000000 ... 0x00001FFF).
4258 So a typical memory configuration with 16 MB of DRAM could look like
4261 0x0000 0000 Exception Vector code
4264 0x0000 2000 Free for Application Use
4270 0x00FB FF20 Monitor Stack (Growing downward)
4271 0x00FB FFAC Board Info Data and permanent copy of global data
4272 0x00FC 0000 Malloc Arena
4275 0x00FE 0000 RAM Copy of Monitor Code
4276 ... eventually: LCD or video framebuffer
4277 ... eventually: pRAM (Protected RAM - unchanged by reset)
4278 0x00FF FFFF [End of RAM]
4281 System Initialization:
4282 ----------------------
4284 In the reset configuration, U-Boot starts at the reset entry point
4285 (on most PowerPC systems at address 0x00000100). Because of the reset
4286 configuration for CS0# this is a mirror of the onboard Flash memory.
4287 To be able to re-map memory U-Boot then jumps to its link address.
4288 To be able to implement the initialization code in C, a (small!)
4289 initial stack is set up in the internal Dual Ported RAM (in case CPUs
4290 which provide such a feature like MPC8xx or MPC8260), or in a locked
4291 part of the data cache. After that, U-Boot initializes the CPU core,
4292 the caches and the SIU.
4294 Next, all (potentially) available memory banks are mapped using a
4295 preliminary mapping. For example, we put them on 512 MB boundaries
4296 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
4297 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
4298 programmed for SDRAM access. Using the temporary configuration, a
4299 simple memory test is run that determines the size of the SDRAM
4302 When there is more than one SDRAM bank, and the banks are of
4303 different size, the largest is mapped first. For equal size, the first
4304 bank (CS2#) is mapped first. The first mapping is always for address
4305 0x00000000, with any additional banks following immediately to create
4306 contiguous memory starting from 0.
4308 Then, the monitor installs itself at the upper end of the SDRAM area
4309 and allocates memory for use by malloc() and for the global Board
4310 Info data; also, the exception vector code is copied to the low RAM
4311 pages, and the final stack is set up.
4313 Only after this relocation will you have a "normal" C environment;
4314 until that you are restricted in several ways, mostly because you are
4315 running from ROM, and because the code will have to be relocated to a
4319 U-Boot Porting Guide:
4320 ----------------------
4322 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
4326 int main(int argc, char *argv[])
4328 sighandler_t no_more_time;
4330 signal(SIGALRM, no_more_time);
4331 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
4333 if (available_money > available_manpower) {
4334 Pay consultant to port U-Boot;
4338 Download latest U-Boot source;
4340 Subscribe to u-boot mailing list;
4343 email("Hi, I am new to U-Boot, how do I get started?");
4346 Read the README file in the top level directory;
4347 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
4348 Read applicable doc/*.README;
4349 Read the source, Luke;
4350 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
4353 if (available_money > toLocalCurrency ($2500))
4356 Add a lot of aggravation and time;
4358 if (a similar board exists) { /* hopefully... */
4359 cp -a board/<similar> board/<myboard>
4360 cp include/configs/<similar>.h include/configs/<myboard>.h
4362 Create your own board support subdirectory;
4363 Create your own board include/configs/<myboard>.h file;
4365 Edit new board/<myboard> files
4366 Edit new include/configs/<myboard>.h
4371 Add / modify source code;
4375 email("Hi, I am having problems...");
4377 Send patch file to the U-Boot email list;
4378 if (reasonable critiques)
4379 Incorporate improvements from email list code review;
4381 Defend code as written;
4387 void no_more_time (int sig)
4396 All contributions to U-Boot should conform to the Linux kernel
4397 coding style; see the file "Documentation/CodingStyle" and the script
4398 "scripts/Lindent" in your Linux kernel source directory. In sources
4399 originating from U-Boot a style corresponding to "Lindent -pcs" (adding
4400 spaces before parameters to function calls) is actually used.
4402 Source files originating from a different project (for example the
4403 MTD subsystem) are generally exempt from these guidelines and are not
4404 reformated to ease subsequent migration to newer versions of those
4407 Please note that U-Boot is implemented in C (and to some small parts in
4408 Assembler); no C++ is used, so please do not use C++ style comments (//)
4411 Please also stick to the following formatting rules:
4412 - remove any trailing white space
4413 - use TAB characters for indentation, not spaces
4414 - make sure NOT to use DOS '\r\n' line feeds
4415 - do not add more than 2 empty lines to source files
4416 - do not add trailing empty lines to source files
4418 Submissions which do not conform to the standards may be returned
4419 with a request to reformat the changes.
4425 Since the number of patches for U-Boot is growing, we need to
4426 establish some rules. Submissions which do not conform to these rules
4427 may be rejected, even when they contain important and valuable stuff.
4429 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
4431 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
4432 see http://lists.denx.de/mailman/listinfo/u-boot
4434 When you send a patch, please include the following information with
4437 * For bug fixes: a description of the bug and how your patch fixes
4438 this bug. Please try to include a way of demonstrating that the
4439 patch actually fixes something.
4441 * For new features: a description of the feature and your
4444 * A CHANGELOG entry as plaintext (separate from the patch)
4446 * For major contributions, your entry to the CREDITS file
4448 * When you add support for a new board, don't forget to add this
4449 board to the MAKEALL script, too.
4451 * If your patch adds new configuration options, don't forget to
4452 document these in the README file.
4454 * The patch itself. If you are using git (which is *strongly*
4455 recommended) you can easily generate the patch using the
4456 "git-format-patch". If you then use "git-send-email" to send it to
4457 the U-Boot mailing list, you will avoid most of the common problems
4458 with some other mail clients.
4460 If you cannot use git, use "diff -purN OLD NEW". If your version of
4461 diff does not support these options, then get the latest version of
4464 The current directory when running this command shall be the parent
4465 directory of the U-Boot source tree (i. e. please make sure that
4466 your patch includes sufficient directory information for the
4469 We prefer patches as plain text. MIME attachments are discouraged,
4470 and compressed attachments must not be used.
4472 * If one logical set of modifications affects or creates several
4473 files, all these changes shall be submitted in a SINGLE patch file.
4475 * Changesets that contain different, unrelated modifications shall be
4476 submitted as SEPARATE patches, one patch per changeset.
4481 * Before sending the patch, run the MAKEALL script on your patched
4482 source tree and make sure that no errors or warnings are reported
4483 for any of the boards.
4485 * Keep your modifications to the necessary minimum: A patch
4486 containing several unrelated changes or arbitrary reformats will be
4487 returned with a request to re-formatting / split it.
4489 * If you modify existing code, make sure that your new code does not
4490 add to the memory footprint of the code ;-) Small is beautiful!
4491 When adding new features, these should compile conditionally only
4492 (using #ifdef), and the resulting code with the new feature
4493 disabled must not need more memory than the old code without your
4496 * Remember that there is a size limit of 100 kB per message on the
4497 u-boot mailing list. Bigger patches will be moderated. If they are
4498 reasonable and not too big, they will be acknowledged. But patches
4499 bigger than the size limit should be avoided.
projects / karo-tx-uboot.git / blob