2 # (C) Copyright 2000 - 2005
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.
60 In case you have questions about, problems with or contributions for
61 U-Boot you should send a message to the U-Boot mailing list at
62 <u-boot-users@lists.sourceforge.net>. There is also an archive of
63 previous traffic on the mailing list - please search the archive
64 before asking FAQ's. Please see
65 http://lists.sourceforge.net/lists/listinfo/u-boot-users/
71 - start from 8xxrom sources
72 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
74 - make it easier to add custom boards
75 - make it possible to add other [PowerPC] CPUs
76 - extend functions, especially:
77 * Provide extended interface to Linux boot loader
80 * PCMCIA / CompactFLash / ATA disk / SCSI ... boot
81 - create ARMBoot project (http://sourceforge.net/projects/armboot)
82 - add other CPU families (starting with ARM)
83 - create U-Boot project (http://sourceforge.net/projects/u-boot)
89 The "official" name of this project is "Das U-Boot". The spelling
90 "U-Boot" shall be used in all written text (documentation, comments
91 in source files etc.). Example:
93 This is the README file for the U-Boot project.
95 File names etc. shall be based on the string "u-boot". Examples:
97 include/asm-ppc/u-boot.h
99 #include <asm/u-boot.h>
101 Variable names, preprocessor constants etc. shall be either based on
102 the string "u_boot" or on "U_BOOT". Example:
104 U_BOOT_VERSION u_boot_logo
105 IH_OS_U_BOOT u_boot_hush_start
111 U-Boot uses a 3 level version number containing a version, a
112 sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2",
113 sub-version "34", and patchlevel "4".
115 The patchlevel is used to indicate certain stages of development
116 between released versions, i. e. officially released versions of
117 U-Boot will always have a patchlevel of "0".
123 - board Board dependent files
124 - common Misc architecture independent functions
125 - cpu CPU specific files
126 - 74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
127 - arm720t Files specific to ARM 720 CPUs
128 - arm920t Files specific to ARM 920 CPUs
129 - at91rm9200 Files specific to Atmel AT91RM9200 CPU
130 - imx Files specific to Freescale MC9328 i.MX CPUs
131 - s3c24x0 Files specific to Samsung S3C24X0 CPUs
132 - arm925t Files specific to ARM 925 CPUs
133 - arm926ejs Files specific to ARM 926 CPUs
134 - arm1136 Files specific to ARM 1136 CPUs
135 - i386 Files specific to i386 CPUs
136 - ixp Files specific to Intel XScale IXP CPUs
137 - mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
138 - mips Files specific to MIPS CPUs
139 - mpc5xx Files specific to Freescale MPC5xx CPUs
140 - mpc5xxx Files specific to Freescale MPC5xxx CPUs
141 - mpc8xx Files specific to Freescale MPC8xx CPUs
142 - mpc8220 Files specific to Freescale MPC8220 CPUs
143 - mpc824x Files specific to Freescale MPC824x CPUs
144 - mpc8260 Files specific to Freescale MPC8260 CPUs
145 - mpc85xx Files specific to Freescale MPC85xx CPUs
146 - nios Files specific to Altera NIOS CPUs
147 - nios2 Files specific to Altera Nios-II CPUs
148 - ppc4xx Files specific to AMCC PowerPC 4xx CPUs
149 - pxa Files specific to Intel XScale PXA CPUs
150 - s3c44b0 Files specific to Samsung S3C44B0 CPUs
151 - sa1100 Files specific to Intel StrongARM SA1100 CPUs
152 - disk Code for disk drive partition handling
153 - doc Documentation (don't expect too much)
154 - drivers Commonly used device drivers
155 - dtt Digital Thermometer and Thermostat drivers
156 - examples Example code for standalone applications, etc.
157 - include Header Files
158 - lib_arm Files generic to ARM architecture
159 - lib_generic Files generic to all architectures
160 - lib_i386 Files generic to i386 architecture
161 - lib_m68k Files generic to m68k architecture
162 - lib_mips Files generic to MIPS architecture
163 - lib_nios Files generic to NIOS architecture
164 - lib_ppc Files generic to PowerPC architecture
165 - net Networking code
166 - post Power On Self Test
167 - rtc Real Time Clock drivers
168 - tools Tools to build S-Record or U-Boot images, etc.
170 Software Configuration:
171 =======================
173 Configuration is usually done using C preprocessor defines; the
174 rationale behind that is to avoid dead code whenever possible.
176 There are two classes of configuration variables:
178 * Configuration _OPTIONS_:
179 These are selectable by the user and have names beginning with
182 * Configuration _SETTINGS_:
183 These depend on the hardware etc. and should not be meddled with if
184 you don't know what you're doing; they have names beginning with
187 Later we will add a configuration tool - probably similar to or even
188 identical to what's used for the Linux kernel. Right now, we have to
189 do the configuration by hand, which means creating some symbolic
190 links and editing some configuration files. We use the TQM8xxL boards
194 Selection of Processor Architecture and Board Type:
195 ---------------------------------------------------
197 For all supported boards there are ready-to-use default
198 configurations available; just type "make <board_name>_config".
200 Example: For a TQM823L module type:
205 For the Cogent platform, you need to specify the cpu type as well;
206 e.g. "make cogent_mpc8xx_config". And also configure the cogent
207 directory according to the instructions in cogent/README.
210 Configuration Options:
211 ----------------------
213 Configuration depends on the combination of board and CPU type; all
214 such information is kept in a configuration file
215 "include/configs/<board_name>.h".
217 Example: For a TQM823L module, all configuration settings are in
218 "include/configs/TQM823L.h".
221 Many of the options are named exactly as the corresponding Linux
222 kernel configuration options. The intention is to make it easier to
223 build a config tool - later.
226 The following options need to be configured:
228 - CPU Type: Define exactly one of
232 CONFIG_MPC823, CONFIG_MPC850, CONFIG_MPC855, CONFIG_MPC860
235 or CONFIG_MPC824X, CONFIG_MPC8260
250 MicroBlaze based CPUs:
251 ----------------------
255 ----------------------
259 - Board Type: Define exactly one of
261 PowerPC based boards:
262 ---------------------
264 CONFIG_ADCIOP CONFIG_GEN860T CONFIG_PCIPPC2
265 CONFIG_ADS860 CONFIG_GENIETV CONFIG_PCIPPC6
266 CONFIG_AMX860 CONFIG_GTH CONFIG_pcu_e
267 CONFIG_AP1000 CONFIG_gw8260 CONFIG_PIP405
268 CONFIG_AR405 CONFIG_hermes CONFIG_PM826
269 CONFIG_BAB7xx CONFIG_hymod CONFIG_ppmc8260
270 CONFIG_c2mon CONFIG_IAD210 CONFIG_QS823
271 CONFIG_CANBT CONFIG_ICU862 CONFIG_QS850
272 CONFIG_CCM CONFIG_IP860 CONFIG_QS860T
273 CONFIG_CMI CONFIG_IPHASE4539 CONFIG_RBC823
274 CONFIG_cogent_mpc8260 CONFIG_IVML24 CONFIG_RPXClassic
275 CONFIG_cogent_mpc8xx CONFIG_IVML24_128 CONFIG_RPXlite
276 CONFIG_CPCI405 CONFIG_IVML24_256 CONFIG_RPXsuper
277 CONFIG_CPCI4052 CONFIG_IVMS8 CONFIG_rsdproto
278 CONFIG_CPCIISER4 CONFIG_IVMS8_128 CONFIG_sacsng
279 CONFIG_CPU86 CONFIG_IVMS8_256 CONFIG_Sandpoint8240
280 CONFIG_CRAYL1 CONFIG_JSE CONFIG_Sandpoint8245
281 CONFIG_CSB272 CONFIG_LANTEC CONFIG_sbc8260
282 CONFIG_CU824 CONFIG_lwmon CONFIG_sbc8560
283 CONFIG_DASA_SIM CONFIG_MBX CONFIG_SM850
284 CONFIG_DB64360 CONFIG_MBX860T CONFIG_SPD823TS
285 CONFIG_DB64460 CONFIG_MHPC CONFIG_STXGP3
286 CONFIG_DU405 CONFIG_MIP405 CONFIG_SXNI855T
287 CONFIG_DUET_ADS CONFIG_MOUSSE CONFIG_TQM823L
288 CONFIG_EBONY CONFIG_MPC8260ADS CONFIG_TQM8260
289 CONFIG_ELPPC CONFIG_MPC8540ADS CONFIG_TQM850L
290 CONFIG_ELPT860 CONFIG_MPC8540EVAL CONFIG_TQM855L
291 CONFIG_ep8260 CONFIG_MPC8560ADS CONFIG_TQM860L
292 CONFIG_ERIC CONFIG_MUSENKI CONFIG_TTTech
293 CONFIG_ESTEEM192E CONFIG_MVS1 CONFIG_UTX8245
294 CONFIG_ETX094 CONFIG_NETPHONE CONFIG_V37
295 CONFIG_EVB64260 CONFIG_NETTA CONFIG_W7OLMC
296 CONFIG_FADS823 CONFIG_NETVIA CONFIG_W7OLMG
297 CONFIG_FADS850SAR CONFIG_NX823 CONFIG_WALNUT
298 CONFIG_FADS860T CONFIG_OCRTC CONFIG_ZPC1900
299 CONFIG_FLAGADM CONFIG_ORSG CONFIG_ZUMA
300 CONFIG_FPS850L CONFIG_OXC
301 CONFIG_FPS860L CONFIG_PCI405
306 CONFIG_ARMADILLO, CONFIG_AT91RM9200DK, CONFIG_CERF250,
307 CONFIG_CSB637, CONFIG_DNP1110, CONFIG_EP7312,
308 CONFIG_H2_OMAP1610, CONFIG_HHP_CRADLE, CONFIG_IMPA7,
309 CONFIG_INNOVATOROMAP1510, CONFIG_INNOVATOROMAP1610, CONFIG_KB9202,
310 CONFIG_LART, CONFIG_LPD7A400, CONFIG_LUBBOCK,
311 CONFIG_OSK_OMAP5912, CONFIG_OMAP2420H4, CONFIG_SHANNON,
312 CONFIG_P2_OMAP730, CONFIG_SMDK2400, CONFIG_SMDK2410,
313 CONFIG_TRAB, CONFIG_VCMA9
315 MicroBlaze based boards:
316 ------------------------
321 ------------------------
323 CONFIG_PCI5441 CONFIG_PK1C20
326 - CPU Module Type: (if CONFIG_COGENT is defined)
327 Define exactly one of
329 --- FIXME --- not tested yet:
330 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
331 CONFIG_CMA287_23, CONFIG_CMA287_50
333 - Motherboard Type: (if CONFIG_COGENT is defined)
334 Define exactly one of
335 CONFIG_CMA101, CONFIG_CMA102
337 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
338 Define one or more of
341 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
342 Define one or more of
343 CONFIG_LCD_HEARTBEAT - update a character position on
344 the lcd display every second with
347 - Board flavour: (if CONFIG_MPC8260ADS is defined)
350 CFG_8260ADS - original MPC8260ADS
351 CFG_8266ADS - MPC8266ADS
352 CFG_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
353 CFG_8272ADS - MPC8272ADS
355 - MPC824X Family Member (if CONFIG_MPC824X is defined)
356 Define exactly one of
357 CONFIG_MPC8240, CONFIG_MPC8245
359 - 8xx CPU Options: (if using an MPC8xx cpu)
360 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
361 get_gclk_freq() cannot work
362 e.g. if there is no 32KHz
363 reference PIT/RTC clock
364 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
367 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
370 CONFIG_8xx_CPUCLK_DEFAULT
371 See doc/README.MPC866
375 Define this to measure the actual CPU clock instead
376 of relying on the correctness of the configured
377 values. Mostly useful for board bringup to make sure
378 the PLL is locked at the intended frequency. Note
379 that this requires a (stable) reference clock (32 kHz
380 RTC clock or CFG_8XX_XIN)
382 - Linux Kernel Interface:
385 U-Boot stores all clock information in Hz
386 internally. For binary compatibility with older Linux
387 kernels (which expect the clocks passed in the
388 bd_info data to be in MHz) the environment variable
389 "clocks_in_mhz" can be defined so that U-Boot
390 converts clock data to MHZ before passing it to the
392 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
393 "clocks_in_mhz=1" is automatically included in the
396 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
398 When transfering memsize parameter to linux, some versions
399 expect it to be in bytes, others in MB.
400 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
404 New kernel versions are expecting firmware settings to be
405 passed using flat open firmware trees.
406 The environment variable "disable_of", when set, disables this
409 CONFIG_OF_FLAT_TREE_MAX_SIZE
411 The maximum size of the constructed OF tree.
413 OF_CPU - The proper name of the cpus node.
414 OF_TBCLK - The timebase frequency.
419 Define this if you want support for Amba PrimeCell PL010 UARTs.
423 Define this if you want support for Amba PrimeCell PL011 UARTs.
427 If you have Amba PrimeCell PL011 UARTs, set this variable to
428 the clock speed of the UARTs.
432 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
433 define this to a list of base addresses for each (supported)
434 port. See e.g. include/configs/versatile.h
438 Depending on board, define exactly one serial port
439 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
440 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
441 console by defining CONFIG_8xx_CONS_NONE
443 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
444 port routines must be defined elsewhere
445 (i.e. serial_init(), serial_getc(), ...)
448 Enables console device for a color framebuffer. Needs following
449 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
450 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
452 VIDEO_HW_RECTFILL graphic chip supports
455 VIDEO_HW_BITBLT graphic chip supports
456 bit-blit (cf. smiLynxEM)
457 VIDEO_VISIBLE_COLS visible pixel columns
459 VIDEO_VISIBLE_ROWS visible pixel rows
460 VIDEO_PIXEL_SIZE bytes per pixel
461 VIDEO_DATA_FORMAT graphic data format
462 (0-5, cf. cfb_console.c)
463 VIDEO_FB_ADRS framebuffer address
464 VIDEO_KBD_INIT_FCT keyboard int fct
465 (i.e. i8042_kbd_init())
466 VIDEO_TSTC_FCT test char fct
468 VIDEO_GETC_FCT get char fct
470 CONFIG_CONSOLE_CURSOR cursor drawing on/off
471 (requires blink timer
473 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
474 CONFIG_CONSOLE_TIME display time/date info in
476 (requires CFG_CMD_DATE)
477 CONFIG_VIDEO_LOGO display Linux logo in
479 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
480 linux_logo.h for logo.
481 Requires CONFIG_VIDEO_LOGO
482 CONFIG_CONSOLE_EXTRA_INFO
483 addional board info beside
486 When CONFIG_CFB_CONSOLE is defined, video console is
487 default i/o. Serial console can be forced with
488 environment 'console=serial'.
490 When CONFIG_SILENT_CONSOLE is defined, all console
491 messages (by U-Boot and Linux!) can be silenced with
492 the "silent" environment variable. See
493 doc/README.silent for more information.
496 CONFIG_BAUDRATE - in bps
497 Select one of the baudrates listed in
498 CFG_BAUDRATE_TABLE, see below.
499 CFG_BRGCLK_PRESCALE, baudrate prescale
501 - Interrupt driven serial port input:
502 CONFIG_SERIAL_SOFTWARE_FIFO
505 Use an interrupt handler for receiving data on the
506 serial port. It also enables using hardware handshake
507 (RTS/CTS) and UART's built-in FIFO. Set the number of
508 bytes the interrupt driven input buffer should have.
510 Leave undefined to disable this feature, including
511 disable the buffer and hardware handshake.
513 - Console UART Number:
517 If defined internal UART1 (and not UART0) is used
518 as default U-Boot console.
520 - Boot Delay: CONFIG_BOOTDELAY - in seconds
521 Delay before automatically booting the default image;
522 set to -1 to disable autoboot.
524 See doc/README.autoboot for these options that
525 work with CONFIG_BOOTDELAY. None are required.
526 CONFIG_BOOT_RETRY_TIME
527 CONFIG_BOOT_RETRY_MIN
528 CONFIG_AUTOBOOT_KEYED
529 CONFIG_AUTOBOOT_PROMPT
530 CONFIG_AUTOBOOT_DELAY_STR
531 CONFIG_AUTOBOOT_STOP_STR
532 CONFIG_AUTOBOOT_DELAY_STR2
533 CONFIG_AUTOBOOT_STOP_STR2
534 CONFIG_ZERO_BOOTDELAY_CHECK
535 CONFIG_RESET_TO_RETRY
539 Only needed when CONFIG_BOOTDELAY is enabled;
540 define a command string that is automatically executed
541 when no character is read on the console interface
542 within "Boot Delay" after reset.
545 This can be used to pass arguments to the bootm
546 command. The value of CONFIG_BOOTARGS goes into the
547 environment value "bootargs".
549 CONFIG_RAMBOOT and CONFIG_NFSBOOT
550 The value of these goes into the environment as
551 "ramboot" and "nfsboot" respectively, and can be used
552 as a convenience, when switching between booting from
558 When this option is #defined, the existence of the
559 environment variable "preboot" will be checked
560 immediately before starting the CONFIG_BOOTDELAY
561 countdown and/or running the auto-boot command resp.
562 entering interactive mode.
564 This feature is especially useful when "preboot" is
565 automatically generated or modified. For an example
566 see the LWMON board specific code: here "preboot" is
567 modified when the user holds down a certain
568 combination of keys on the (special) keyboard when
571 - Serial Download Echo Mode:
573 If defined to 1, all characters received during a
574 serial download (using the "loads" command) are
575 echoed back. This might be needed by some terminal
576 emulations (like "cu"), but may as well just take
577 time on others. This setting #define's the initial
578 value of the "loads_echo" environment variable.
580 - Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined)
582 Select one of the baudrates listed in
583 CFG_BAUDRATE_TABLE, see below.
587 Most monitor functions can be selected (or
588 de-selected) by adjusting the definition of
589 CONFIG_COMMANDS; to select individual functions,
590 #define CONFIG_COMMANDS by "OR"ing any of the
593 #define enables commands:
594 -------------------------
595 CFG_CMD_ASKENV * ask for env variable
596 CFG_CMD_AUTOSCRIPT Autoscript Support
598 CFG_CMD_BEDBUG * Include BedBug Debugger
599 CFG_CMD_BMP * BMP support
600 CFG_CMD_BSP * Board specific commands
602 CFG_CMD_CACHE * icache, dcache
603 CFG_CMD_CONSOLE coninfo
604 CFG_CMD_DATE * support for RTC, date/time...
605 CFG_CMD_DHCP * DHCP support
606 CFG_CMD_DIAG * Diagnostics
607 CFG_CMD_DOC * Disk-On-Chip Support
608 CFG_CMD_DTT * Digital Therm and Thermostat
609 CFG_CMD_ECHO * echo arguments
610 CFG_CMD_EEPROM * EEPROM read/write support
611 CFG_CMD_ELF * bootelf, bootvx
613 CFG_CMD_FDC * Floppy Disk Support
614 CFG_CMD_FAT * FAT partition support
615 CFG_CMD_FDOS * Dos diskette Support
616 CFG_CMD_FLASH flinfo, erase, protect
617 CFG_CMD_FPGA FPGA device initialization support
618 CFG_CMD_HWFLOW * RTS/CTS hw flow control
619 CFG_CMD_I2C * I2C serial bus support
620 CFG_CMD_IDE * IDE harddisk support
622 CFG_CMD_IMLS List all found images
623 CFG_CMD_IMMAP * IMMR dump support
624 CFG_CMD_IRQ * irqinfo
625 CFG_CMD_ITEST Integer/string test of 2 values
626 CFG_CMD_JFFS2 * JFFS2 Support
630 CFG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
632 CFG_CMD_MISC Misc functions like sleep etc
633 CFG_CMD_MMC * MMC memory mapped support
634 CFG_CMD_MII * MII utility commands
635 CFG_CMD_NAND * NAND support
636 CFG_CMD_NET bootp, tftpboot, rarpboot
637 CFG_CMD_PCI * pciinfo
638 CFG_CMD_PCMCIA * PCMCIA support
639 CFG_CMD_PING * send ICMP ECHO_REQUEST to network host
640 CFG_CMD_PORTIO * Port I/O
641 CFG_CMD_REGINFO * Register dump
642 CFG_CMD_RUN run command in env variable
643 CFG_CMD_SAVES * save S record dump
644 CFG_CMD_SCSI * SCSI Support
645 CFG_CMD_SDRAM * print SDRAM configuration information
646 (requires CFG_CMD_I2C)
647 CFG_CMD_SETGETDCR Support for DCR Register access (4xx only)
648 CFG_CMD_SPI * SPI serial bus support
649 CFG_CMD_USB * USB support
650 CFG_CMD_VFD * VFD support (TRAB)
651 CFG_CMD_BSP * Board SPecific functions
652 CFG_CMD_CDP * Cisco Discover Protocol support
653 -----------------------------------------------
656 CONFIG_CMD_DFL Default configuration; at the moment
657 this is includes all commands, except
658 the ones marked with "*" in the list
661 If you don't define CONFIG_COMMANDS it defaults to
662 CONFIG_CMD_DFL in include/cmd_confdefs.h. A board can
663 override the default settings in the respective
666 EXAMPLE: If you want all functions except of network
667 support you can write:
669 #define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET)
672 Note: Don't enable the "icache" and "dcache" commands
673 (configuration option CFG_CMD_CACHE) unless you know
674 what you (and your U-Boot users) are doing. Data
675 cache cannot be enabled on systems like the 8xx or
676 8260 (where accesses to the IMMR region must be
677 uncached), and it cannot be disabled on all other
678 systems where we (mis-) use the data cache to hold an
679 initial stack and some data.
682 XXX - this list needs to get updated!
686 If this variable is defined, it enables watchdog
687 support. There must be support in the platform specific
688 code for a watchdog. For the 8xx and 8260 CPUs, the
689 SIU Watchdog feature is enabled in the SYPCR
693 CONFIG_VERSION_VARIABLE
694 If this variable is defined, an environment variable
695 named "ver" is created by U-Boot showing the U-Boot
696 version as printed by the "version" command.
697 This variable is readonly.
701 When CFG_CMD_DATE is selected, the type of the RTC
702 has to be selected, too. Define exactly one of the
705 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
706 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
707 CONFIG_RTC_MC146818 - use MC146818 RTC
708 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
709 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
710 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
711 CONFIG_RTC_DS164x - use Dallas DS164x RTC
712 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
714 Note that if the RTC uses I2C, then the I2C interface
715 must also be configured. See I2C Support, below.
719 When CONFIG_TIMESTAMP is selected, the timestamp
720 (date and time) of an image is printed by image
721 commands like bootm or iminfo. This option is
722 automatically enabled when you select CFG_CMD_DATE .
725 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
726 and/or CONFIG_ISO_PARTITION
728 If IDE or SCSI support is enabled (CFG_CMD_IDE or
729 CFG_CMD_SCSI) you must configure support for at least
730 one partition type as well.
733 CONFIG_IDE_RESET_ROUTINE - this is defined in several
734 board configurations files but used nowhere!
736 CONFIG_IDE_RESET - is this is defined, IDE Reset will
737 be performed by calling the function
738 ide_set_reset(int reset)
739 which has to be defined in a board specific file
744 Set this to enable ATAPI support.
749 Set this to enable support for disks larger than 137GB
750 Also look at CFG_64BIT_LBA ,CFG_64BIT_VSPRINTF and CFG_64BIT_STRTOUL
751 Whithout these , LBA48 support uses 32bit variables and will 'only'
752 support disks up to 2.1TB.
755 When enabled, makes the IDE subsystem use 64bit sector addresses.
759 At the moment only there is only support for the
760 SYM53C8XX SCSI controller; define
761 CONFIG_SCSI_SYM53C8XX to enable it.
763 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and
764 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID *
765 CFG_SCSI_MAX_LUN] can be adjusted to define the
766 maximum numbers of LUNs, SCSI ID's and target
768 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
770 - NETWORK Support (PCI):
772 Support for Intel 8254x gigabit chips.
775 Support for Intel 82557/82559/82559ER chips.
776 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom
777 write routine for first time initialisation.
780 Support for Digital 2114x chips.
781 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
782 modem chip initialisation (KS8761/QS6611).
785 Support for National dp83815 chips.
788 Support for National dp8382[01] gigabit chips.
790 - NETWORK Support (other):
792 CONFIG_DRIVER_LAN91C96
793 Support for SMSC's LAN91C96 chips.
796 Define this to hold the physical address
797 of the LAN91C96's I/O space
799 CONFIG_LAN91C96_USE_32_BIT
800 Define this to enable 32 bit addressing
802 CONFIG_DRIVER_SMC91111
803 Support for SMSC's LAN91C111 chip
806 Define this to hold the physical address
807 of the device (I/O space)
809 CONFIG_SMC_USE_32_BIT
810 Define this if data bus is 32 bits
812 CONFIG_SMC_USE_IOFUNCS
813 Define this to use i/o functions instead of macros
814 (some hardware wont work with macros)
817 At the moment only the UHCI host controller is
818 supported (PIP405, MIP405, MPC5200); define
819 CONFIG_USB_UHCI to enable it.
820 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
821 and define CONFIG_USB_STORAGE to enable the USB
824 Supported are USB Keyboards and USB Floppy drives
826 MPC5200 USB requires additional defines:
828 for 528 MHz Clock: 0x0001bbbb
830 for differential drivers: 0x00001000
831 for single ended drivers: 0x00005000
835 The MMC controller on the Intel PXA is supported. To
836 enable this define CONFIG_MMC. The MMC can be
837 accessed from the boot prompt by mapping the device
838 to physical memory similar to flash. Command line is
839 enabled with CFG_CMD_MMC. The MMC driver also works with
840 the FAT fs. This is enabled with CFG_CMD_FAT.
842 - Journaling Flash filesystem support:
843 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
844 CONFIG_JFFS2_NAND_DEV
845 Define these for a default partition on a NAND device
847 CFG_JFFS2_FIRST_SECTOR,
848 CFG_JFFS2_FIRST_BANK, CFG_JFFS2_NUM_BANKS
849 Define these for a default partition on a NOR device
852 Define this to create an own partition. You have to provide a
853 function struct part_info* jffs2_part_info(int part_num)
855 If you define only one JFFS2 partition you may also want to
856 #define CFG_JFFS_SINGLE_PART 1
857 to disable the command chpart. This is the default when you
858 have not defined a custom partition
863 Define this to enable standard (PC-Style) keyboard
867 Standard PC keyboard driver with US (is default) and
868 GERMAN key layout (switch via environment 'keymap=de') support.
869 Export function i8042_kbd_init, i8042_tstc and i8042_getc
870 for cfb_console. Supports cursor blinking.
875 Define this to enable video support (for output to
880 Enable Chips & Technologies 69000 Video chip
882 CONFIG_VIDEO_SMI_LYNXEM
883 Enable Silicon Motion SMI 712/710/810 Video chip. The
884 video output is selected via environment 'videoout'
885 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
888 For the CT69000 and SMI_LYNXEM drivers, videomode is
889 selected via environment 'videomode'. Two diferent ways
891 - "videomode=num" 'num' is a standard LiLo mode numbers.
892 Following standard modes are supported (* is default):
894 Colors 640x480 800x600 1024x768 1152x864 1280x1024
895 -------------+---------------------------------------------
896 8 bits | 0x301* 0x303 0x305 0x161 0x307
897 15 bits | 0x310 0x313 0x316 0x162 0x319
898 16 bits | 0x311 0x314 0x317 0x163 0x31A
899 24 bits | 0x312 0x315 0x318 ? 0x31B
900 -------------+---------------------------------------------
901 (i.e. setenv videomode 317; saveenv; reset;)
903 - "videomode=bootargs" all the video parameters are parsed
904 from the bootargs. (See drivers/videomodes.c)
907 CONFIG_VIDEO_SED13806
908 Enable Epson SED13806 driver. This driver supports 8bpp
909 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
910 or CONFIG_VIDEO_SED13806_16BPP
915 Define this to enable a custom keyboard support.
916 This simply calls drv_keyboard_init() which must be
917 defined in your board-specific files.
918 The only board using this so far is RBC823.
920 - LCD Support: CONFIG_LCD
922 Define this to enable LCD support (for output to LCD
923 display); also select one of the supported displays
924 by defining one of these:
926 CONFIG_NEC_NL6448AC33:
928 NEC NL6448AC33-18. Active, color, single scan.
930 CONFIG_NEC_NL6448BC20
932 NEC NL6448BC20-08. 6.5", 640x480.
933 Active, color, single scan.
935 CONFIG_NEC_NL6448BC33_54
937 NEC NL6448BC33-54. 10.4", 640x480.
938 Active, color, single scan.
942 Sharp 320x240. Active, color, single scan.
943 It isn't 16x9, and I am not sure what it is.
945 CONFIG_SHARP_LQ64D341
947 Sharp LQ64D341 display, 640x480.
948 Active, color, single scan.
952 HLD1045 display, 640x480.
953 Active, color, single scan.
957 Optrex CBL50840-2 NF-FW 99 22 M5
959 Hitachi LMG6912RPFC-00T
963 320x240. Black & white.
965 Normally display is black on white background; define
966 CFG_WHITE_ON_BLACK to get it inverted.
968 - Splash Screen Support: CONFIG_SPLASH_SCREEN
970 If this option is set, the environment is checked for
971 a variable "splashimage". If found, the usual display
972 of logo, copyright and system information on the LCD
973 is suppressed and the BMP image at the address
974 specified in "splashimage" is loaded instead. The
975 console is redirected to the "nulldev", too. This
976 allows for a "silent" boot where a splash screen is
977 loaded very quickly after power-on.
979 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
981 If this option is set, additionally to standard BMP
982 images, gzipped BMP images can be displayed via the
983 splashscreen support or the bmp command.
985 - Compression support:
988 If this option is set, support for bzip2 compressed
989 images is included. If not, only uncompressed and gzip
990 compressed images are supported.
992 NOTE: the bzip2 algorithm requires a lot of RAM, so
993 the malloc area (as defined by CFG_MALLOC_LEN) should
999 The address of PHY on MII bus.
1001 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1003 The clock frequency of the MII bus
1007 If this option is set, support for speed/duplex
1008 detection of Gigabit PHY is included.
1010 CONFIG_PHY_RESET_DELAY
1012 Some PHY like Intel LXT971A need extra delay after
1013 reset before any MII register access is possible.
1014 For such PHY, set this option to the usec delay
1015 required. (minimum 300usec for LXT971A)
1017 CONFIG_PHY_CMD_DELAY (ppc4xx)
1019 Some PHY like Intel LXT971A need extra delay after
1020 command issued before MII status register can be read
1027 Define a default value for ethernet address to use
1028 for the respective ethernet interface, in case this
1029 is not determined automatically.
1034 Define a default value for the IP address to use for
1035 the default ethernet interface, in case this is not
1036 determined through e.g. bootp.
1038 - Server IP address:
1041 Defines a default value for theIP address of a TFTP
1042 server to contact when using the "tftboot" command.
1044 - BOOTP Recovery Mode:
1045 CONFIG_BOOTP_RANDOM_DELAY
1047 If you have many targets in a network that try to
1048 boot using BOOTP, you may want to avoid that all
1049 systems send out BOOTP requests at precisely the same
1050 moment (which would happen for instance at recovery
1051 from a power failure, when all systems will try to
1052 boot, thus flooding the BOOTP server. Defining
1053 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1054 inserted before sending out BOOTP requests. The
1055 following delays are insterted then:
1057 1st BOOTP request: delay 0 ... 1 sec
1058 2nd BOOTP request: delay 0 ... 2 sec
1059 3rd BOOTP request: delay 0 ... 4 sec
1061 BOOTP requests: delay 0 ... 8 sec
1063 - DHCP Advanced Options:
1066 You can fine tune the DHCP functionality by adding
1067 these flags to the CONFIG_BOOTP_MASK define:
1069 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1070 serverip from a DHCP server, it is possible that more
1071 than one DNS serverip is offered to the client.
1072 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1073 serverip will be stored in the additional environment
1074 variable "dnsip2". The first DNS serverip is always
1075 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1076 is added to the CONFIG_BOOTP_MASK.
1078 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1079 to do a dynamic update of a DNS server. To do this, they
1080 need the hostname of the DHCP requester.
1081 If CONFIG_BOOP_SEND_HOSTNAME is added to the
1082 CONFIG_BOOTP_MASK, the content of the "hostname"
1083 environment variable is passed as option 12 to
1087 CONFIG_CDP_DEVICE_ID
1089 The device id used in CDP trigger frames.
1091 CONFIG_CDP_DEVICE_ID_PREFIX
1093 A two character string which is prefixed to the MAC address
1098 A printf format string which contains the ascii name of
1099 the port. Normally is set to "eth%d" which sets
1100 eth0 for the first ethernet, eth1 for the second etc.
1102 CONFIG_CDP_CAPABILITIES
1104 A 32bit integer which indicates the device capabilities;
1105 0x00000010 for a normal host which does not forwards.
1109 An ascii string containing the version of the software.
1113 An ascii string containing the name of the platform.
1117 A 32bit integer sent on the trigger.
1119 CONFIG_CDP_POWER_CONSUMPTION
1121 A 16bit integer containing the power consumption of the
1122 device in .1 of milliwatts.
1124 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1126 A byte containing the id of the VLAN.
1128 - Status LED: CONFIG_STATUS_LED
1130 Several configurations allow to display the current
1131 status using a LED. For instance, the LED will blink
1132 fast while running U-Boot code, stop blinking as
1133 soon as a reply to a BOOTP request was received, and
1134 start blinking slow once the Linux kernel is running
1135 (supported by a status LED driver in the Linux
1136 kernel). Defining CONFIG_STATUS_LED enables this
1139 - CAN Support: CONFIG_CAN_DRIVER
1141 Defining CONFIG_CAN_DRIVER enables CAN driver support
1142 on those systems that support this (optional)
1143 feature, like the TQM8xxL modules.
1145 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1147 These enable I2C serial bus commands. Defining either of
1148 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1149 include the appropriate I2C driver for the selected cpu.
1151 This will allow you to use i2c commands at the u-boot
1152 command line (as long as you set CFG_CMD_I2C in
1153 CONFIG_COMMANDS) and communicate with i2c based realtime
1154 clock chips. See common/cmd_i2c.c for a description of the
1155 command line interface.
1157 CONFIG_HARD_I2C selects the CPM hardware driver for I2C.
1159 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1160 bit-banging) driver instead of CPM or similar hardware
1163 There are several other quantities that must also be
1164 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1166 In both cases you will need to define CFG_I2C_SPEED
1167 to be the frequency (in Hz) at which you wish your i2c bus
1168 to run and CFG_I2C_SLAVE to be the address of this node (ie
1169 the cpu's i2c node address).
1171 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c)
1172 sets the cpu up as a master node and so its address should
1173 therefore be cleared to 0 (See, eg, MPC823e User's Manual
1174 p.16-473). So, set CFG_I2C_SLAVE to 0.
1176 That's all that's required for CONFIG_HARD_I2C.
1178 If you use the software i2c interface (CONFIG_SOFT_I2C)
1179 then the following macros need to be defined (examples are
1180 from include/configs/lwmon.h):
1184 (Optional). Any commands necessary to enable the I2C
1185 controller or configure ports.
1187 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1191 (Only for MPC8260 CPU). The I/O port to use (the code
1192 assumes both bits are on the same port). Valid values
1193 are 0..3 for ports A..D.
1197 The code necessary to make the I2C data line active
1198 (driven). If the data line is open collector, this
1201 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1205 The code necessary to make the I2C data line tri-stated
1206 (inactive). If the data line is open collector, this
1209 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1213 Code that returns TRUE if the I2C data line is high,
1216 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1220 If <bit> is TRUE, sets the I2C data line high. If it
1221 is FALSE, it clears it (low).
1223 eg: #define I2C_SDA(bit) \
1224 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1225 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1229 If <bit> is TRUE, sets the I2C clock line high. If it
1230 is FALSE, it clears it (low).
1232 eg: #define I2C_SCL(bit) \
1233 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1234 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1238 This delay is invoked four times per clock cycle so this
1239 controls the rate of data transfer. The data rate thus
1240 is 1 / (I2C_DELAY * 4). Often defined to be something
1243 #define I2C_DELAY udelay(2)
1247 When a board is reset during an i2c bus transfer
1248 chips might think that the current transfer is still
1249 in progress. On some boards it is possible to access
1250 the i2c SCLK line directly, either by using the
1251 processor pin as a GPIO or by having a second pin
1252 connected to the bus. If this option is defined a
1253 custom i2c_init_board() routine in boards/xxx/board.c
1254 is run early in the boot sequence.
1256 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
1258 This option enables configuration of bi_iic_fast[] flags
1259 in u-boot bd_info structure based on u-boot environment
1260 variable "i2cfast". (see also i2cfast)
1262 - SPI Support: CONFIG_SPI
1264 Enables SPI driver (so far only tested with
1265 SPI EEPROM, also an instance works with Crystal A/D and
1266 D/As on the SACSng board)
1270 Enables extended (16-bit) SPI EEPROM addressing.
1271 (symmetrical to CONFIG_I2C_X)
1275 Enables a software (bit-bang) SPI driver rather than
1276 using hardware support. This is a general purpose
1277 driver that only requires three general I/O port pins
1278 (two outputs, one input) to function. If this is
1279 defined, the board configuration must define several
1280 SPI configuration items (port pins to use, etc). For
1281 an example, see include/configs/sacsng.h.
1283 - FPGA Support: CONFIG_FPGA_COUNT
1285 Specify the number of FPGA devices to support.
1289 Used to specify the types of FPGA devices. For example,
1290 #define CONFIG_FPGA CFG_XILINX_VIRTEX2
1292 CFG_FPGA_PROG_FEEDBACK
1294 Enable printing of hash marks during FPGA configuration.
1298 Enable checks on FPGA configuration interface busy
1299 status by the configuration function. This option
1300 will require a board or device specific function to
1305 If defined, a function that provides delays in the FPGA
1306 configuration driver.
1308 CFG_FPGA_CHECK_CTRLC
1309 Allow Control-C to interrupt FPGA configuration
1311 CFG_FPGA_CHECK_ERROR
1313 Check for configuration errors during FPGA bitfile
1314 loading. For example, abort during Virtex II
1315 configuration if the INIT_B line goes low (which
1316 indicated a CRC error).
1320 Maximum time to wait for the INIT_B line to deassert
1321 after PROB_B has been deasserted during a Virtex II
1322 FPGA configuration sequence. The default time is 500
1327 Maximum time to wait for BUSY to deassert during
1328 Virtex II FPGA configuration. The default is 5 mS.
1330 CFG_FPGA_WAIT_CONFIG
1332 Time to wait after FPGA configuration. The default is
1335 - Configuration Management:
1338 If defined, this string will be added to the U-Boot
1339 version information (U_BOOT_VERSION)
1341 - Vendor Parameter Protection:
1343 U-Boot considers the values of the environment
1344 variables "serial#" (Board Serial Number) and
1345 "ethaddr" (Ethernet Address) to be parameters that
1346 are set once by the board vendor / manufacturer, and
1347 protects these variables from casual modification by
1348 the user. Once set, these variables are read-only,
1349 and write or delete attempts are rejected. You can
1350 change this behviour:
1352 If CONFIG_ENV_OVERWRITE is #defined in your config
1353 file, the write protection for vendor parameters is
1354 completely disabled. Anybody can change or delete
1357 Alternatively, if you #define _both_ CONFIG_ETHADDR
1358 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1359 ethernet address is installed in the environment,
1360 which can be changed exactly ONCE by the user. [The
1361 serial# is unaffected by this, i. e. it remains
1367 Define this variable to enable the reservation of
1368 "protected RAM", i. e. RAM which is not overwritten
1369 by U-Boot. Define CONFIG_PRAM to hold the number of
1370 kB you want to reserve for pRAM. You can overwrite
1371 this default value by defining an environment
1372 variable "pram" to the number of kB you want to
1373 reserve. Note that the board info structure will
1374 still show the full amount of RAM. If pRAM is
1375 reserved, a new environment variable "mem" will
1376 automatically be defined to hold the amount of
1377 remaining RAM in a form that can be passed as boot
1378 argument to Linux, for instance like that:
1380 setenv bootargs ... mem=\${mem}
1383 This way you can tell Linux not to use this memory,
1384 either, which results in a memory region that will
1385 not be affected by reboots.
1387 *WARNING* If your board configuration uses automatic
1388 detection of the RAM size, you must make sure that
1389 this memory test is non-destructive. So far, the
1390 following board configurations are known to be
1393 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1394 HERMES, IP860, RPXlite, LWMON, LANTEC,
1395 PCU_E, FLAGADM, TQM8260
1400 Define this variable to stop the system in case of a
1401 fatal error, so that you have to reset it manually.
1402 This is probably NOT a good idea for an embedded
1403 system where you want to system to reboot
1404 automatically as fast as possible, but it may be
1405 useful during development since you can try to debug
1406 the conditions that lead to the situation.
1408 CONFIG_NET_RETRY_COUNT
1410 This variable defines the number of retries for
1411 network operations like ARP, RARP, TFTP, or BOOTP
1412 before giving up the operation. If not defined, a
1413 default value of 5 is used.
1415 - Command Interpreter:
1418 Enable auto completion of commands using TAB.
1422 Define this variable to enable the "hush" shell (from
1423 Busybox) as command line interpreter, thus enabling
1424 powerful command line syntax like
1425 if...then...else...fi conditionals or `&&' and '||'
1426 constructs ("shell scripts").
1428 If undefined, you get the old, much simpler behaviour
1429 with a somewhat smaller memory footprint.
1434 This defines the secondary prompt string, which is
1435 printed when the command interpreter needs more input
1436 to complete a command. Usually "> ".
1440 In the current implementation, the local variables
1441 space and global environment variables space are
1442 separated. Local variables are those you define by
1443 simply typing `name=value'. To access a local
1444 variable later on, you have write `$name' or
1445 `${name}'; to execute the contents of a variable
1446 directly type `$name' at the command prompt.
1448 Global environment variables are those you use
1449 setenv/printenv to work with. To run a command stored
1450 in such a variable, you need to use the run command,
1451 and you must not use the '$' sign to access them.
1453 To store commands and special characters in a
1454 variable, please use double quotation marks
1455 surrounding the whole text of the variable, instead
1456 of the backslashes before semicolons and special
1459 - Default Environment:
1460 CONFIG_EXTRA_ENV_SETTINGS
1462 Define this to contain any number of null terminated
1463 strings (variable = value pairs) that will be part of
1464 the default environment compiled into the boot image.
1466 For example, place something like this in your
1467 board's config file:
1469 #define CONFIG_EXTRA_ENV_SETTINGS \
1473 Warning: This method is based on knowledge about the
1474 internal format how the environment is stored by the
1475 U-Boot code. This is NOT an official, exported
1476 interface! Although it is unlikely that this format
1477 will change soon, there is no guarantee either.
1478 You better know what you are doing here.
1480 Note: overly (ab)use of the default environment is
1481 discouraged. Make sure to check other ways to preset
1482 the environment like the autoscript function or the
1485 - DataFlash Support:
1486 CONFIG_HAS_DATAFLASH
1488 Defining this option enables DataFlash features and
1489 allows to read/write in Dataflash via the standard
1492 - SystemACE Support:
1495 Adding this option adds support for Xilinx SystemACE
1496 chips attached via some sort of local bus. The address
1497 of the chip must alsh be defined in the
1498 CFG_SYSTEMACE_BASE macro. For example:
1500 #define CONFIG_SYSTEMACE
1501 #define CFG_SYSTEMACE_BASE 0xf0000000
1503 When SystemACE support is added, the "ace" device type
1504 becomes available to the fat commands, i.e. fatls.
1506 - TFTP Fixed UDP Port:
1509 If this is defined, the environment variable tftpsrcp
1510 is used to supply the TFTP UDP source port value.
1511 If tftpsrcp isn't defined, the normal pseudo-random port
1512 number generator is used.
1514 Also, the environment variable tftpdstp is used to supply
1515 the TFTP UDP destination port value. If tftpdstp isn't
1516 defined, the normal port 69 is used.
1518 The purpose for tftpsrcp is to allow a TFTP server to
1519 blindly start the TFTP transfer using the pre-configured
1520 target IP address and UDP port. This has the effect of
1521 "punching through" the (Windows XP) firewall, allowing
1522 the remainder of the TFTP transfer to proceed normally.
1523 A better solution is to properly configure the firewall,
1524 but sometimes that is not allowed.
1526 - Show boot progress:
1527 CONFIG_SHOW_BOOT_PROGRESS
1529 Defining this option allows to add some board-
1530 specific code (calling a user-provided function
1531 "show_boot_progress(int)") that enables you to show
1532 the system's boot progress on some display (for
1533 example, some LED's) on your board. At the moment,
1534 the following checkpoints are implemented:
1537 1 common/cmd_bootm.c before attempting to boot an image
1538 -1 common/cmd_bootm.c Image header has bad magic number
1539 2 common/cmd_bootm.c Image header has correct magic number
1540 -2 common/cmd_bootm.c Image header has bad checksum
1541 3 common/cmd_bootm.c Image header has correct checksum
1542 -3 common/cmd_bootm.c Image data has bad checksum
1543 4 common/cmd_bootm.c Image data has correct checksum
1544 -4 common/cmd_bootm.c Image is for unsupported architecture
1545 5 common/cmd_bootm.c Architecture check OK
1546 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1547 6 common/cmd_bootm.c Image Type check OK
1548 -6 common/cmd_bootm.c gunzip uncompression error
1549 -7 common/cmd_bootm.c Unimplemented compression type
1550 7 common/cmd_bootm.c Uncompression OK
1551 -8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1552 8 common/cmd_bootm.c Image Type check OK
1553 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
1554 9 common/cmd_bootm.c Start initial ramdisk verification
1555 -10 common/cmd_bootm.c Ramdisk header has bad magic number
1556 -11 common/cmd_bootm.c Ramdisk header has bad checksum
1557 10 common/cmd_bootm.c Ramdisk header is OK
1558 -12 common/cmd_bootm.c Ramdisk data has bad checksum
1559 11 common/cmd_bootm.c Ramdisk data has correct checksum
1560 12 common/cmd_bootm.c Ramdisk verification complete, start loading
1561 -13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk)
1562 13 common/cmd_bootm.c Start multifile image verification
1563 14 common/cmd_bootm.c No initial ramdisk, no multifile, continue.
1564 15 common/cmd_bootm.c All preparation done, transferring control to OS
1566 -30 lib_ppc/board.c Fatal error, hang the system
1567 -31 post/post.c POST test failed, detected by post_output_backlog()
1568 -32 post/post.c POST test failed, detected by post_run_single()
1570 -1 common/cmd_doc.c Bad usage of "doc" command
1571 -1 common/cmd_doc.c No boot device
1572 -1 common/cmd_doc.c Unknown Chip ID on boot device
1573 -1 common/cmd_doc.c Read Error on boot device
1574 -1 common/cmd_doc.c Image header has bad magic number
1576 -1 common/cmd_ide.c Bad usage of "ide" command
1577 -1 common/cmd_ide.c No boot device
1578 -1 common/cmd_ide.c Unknown boot device
1579 -1 common/cmd_ide.c Unknown partition table
1580 -1 common/cmd_ide.c Invalid partition type
1581 -1 common/cmd_ide.c Read Error on boot device
1582 -1 common/cmd_ide.c Image header has bad magic number
1584 -1 common/cmd_nand.c Bad usage of "nand" command
1585 -1 common/cmd_nand.c No boot device
1586 -1 common/cmd_nand.c Unknown Chip ID on boot device
1587 -1 common/cmd_nand.c Read Error on boot device
1588 -1 common/cmd_nand.c Image header has bad magic number
1590 -1 common/env_common.c Environment has a bad CRC, using default
1596 [so far only for SMDK2400 and TRAB boards]
1598 - Modem support endable:
1599 CONFIG_MODEM_SUPPORT
1601 - RTS/CTS Flow control enable:
1604 - Modem debug support:
1605 CONFIG_MODEM_SUPPORT_DEBUG
1607 Enables debugging stuff (char screen[1024], dbg())
1608 for modem support. Useful only with BDI2000.
1610 - Interrupt support (PPC):
1612 There are common interrupt_init() and timer_interrupt()
1613 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
1614 for cpu specific initialization. interrupt_init_cpu()
1615 should set decrementer_count to appropriate value. If
1616 cpu resets decrementer automatically after interrupt
1617 (ppc4xx) it should set decrementer_count to zero.
1618 timer_interrupt() calls timer_interrupt_cpu() for cpu
1619 specific handling. If board has watchdog / status_led
1620 / other_activity_monitor it works automatically from
1621 general timer_interrupt().
1625 In the target system modem support is enabled when a
1626 specific key (key combination) is pressed during
1627 power-on. Otherwise U-Boot will boot normally
1628 (autoboot). The key_pressed() fuction is called from
1629 board_init(). Currently key_pressed() is a dummy
1630 function, returning 1 and thus enabling modem
1633 If there are no modem init strings in the
1634 environment, U-Boot proceed to autoboot; the
1635 previous output (banner, info printfs) will be
1638 See also: doc/README.Modem
1641 Configuration Settings:
1642 -----------------------
1644 - CFG_LONGHELP: Defined when you want long help messages included;
1645 undefine this when you're short of memory.
1647 - CFG_PROMPT: This is what U-Boot prints on the console to
1648 prompt for user input.
1650 - CFG_CBSIZE: Buffer size for input from the Console
1652 - CFG_PBSIZE: Buffer size for Console output
1654 - CFG_MAXARGS: max. Number of arguments accepted for monitor commands
1656 - CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to
1657 the application (usually a Linux kernel) when it is
1660 - CFG_BAUDRATE_TABLE:
1661 List of legal baudrate settings for this board.
1663 - CFG_CONSOLE_INFO_QUIET
1664 Suppress display of console information at boot.
1666 - CFG_CONSOLE_IS_IN_ENV
1667 If the board specific function
1668 extern int overwrite_console (void);
1669 returns 1, the stdin, stderr and stdout are switched to the
1670 serial port, else the settings in the environment are used.
1672 - CFG_CONSOLE_OVERWRITE_ROUTINE
1673 Enable the call to overwrite_console().
1675 - CFG_CONSOLE_ENV_OVERWRITE
1676 Enable overwrite of previous console environment settings.
1678 - CFG_MEMTEST_START, CFG_MEMTEST_END:
1679 Begin and End addresses of the area used by the
1683 Enable an alternate, more extensive memory test.
1685 - CFG_MEMTEST_SCRATCH:
1686 Scratch address used by the alternate memory test
1687 You only need to set this if address zero isn't writeable
1689 - CFG_TFTP_LOADADDR:
1690 Default load address for network file downloads
1692 - CFG_LOADS_BAUD_CHANGE:
1693 Enable temporary baudrate change while serial download
1696 Physical start address of SDRAM. _Must_ be 0 here.
1699 Physical start address of Motherboard I/O (if using a
1703 Physical start address of Flash memory.
1706 Physical start address of boot monitor code (set by
1707 make config files to be same as the text base address
1708 (TEXT_BASE) used when linking) - same as
1709 CFG_FLASH_BASE when booting from flash.
1712 Size of memory reserved for monitor code, used to
1713 determine _at_compile_time_ (!) if the environment is
1714 embedded within the U-Boot image, or in a separate
1718 Size of DRAM reserved for malloc() use.
1721 Maximum size of memory mapped by the startup code of
1722 the Linux kernel; all data that must be processed by
1723 the Linux kernel (bd_info, boot arguments, eventually
1724 initrd image) must be put below this limit.
1726 - CFG_MAX_FLASH_BANKS:
1727 Max number of Flash memory banks
1729 - CFG_MAX_FLASH_SECT:
1730 Max number of sectors on a Flash chip
1732 - CFG_FLASH_ERASE_TOUT:
1733 Timeout for Flash erase operations (in ms)
1735 - CFG_FLASH_WRITE_TOUT:
1736 Timeout for Flash write operations (in ms)
1738 - CFG_FLASH_LOCK_TOUT
1739 Timeout for Flash set sector lock bit operation (in ms)
1741 - CFG_FLASH_UNLOCK_TOUT
1742 Timeout for Flash clear lock bits operation (in ms)
1744 - CFG_FLASH_PROTECTION
1745 If defined, hardware flash sectors protection is used
1746 instead of U-Boot software protection.
1748 - CFG_DIRECT_FLASH_TFTP:
1750 Enable TFTP transfers directly to flash memory;
1751 without this option such a download has to be
1752 performed in two steps: (1) download to RAM, and (2)
1753 copy from RAM to flash.
1755 The two-step approach is usually more reliable, since
1756 you can check if the download worked before you erase
1757 the flash, but in some situations (when sytem RAM is
1758 too limited to allow for a tempory copy of the
1759 downloaded image) this option may be very useful.
1762 Define if the flash driver uses extra elements in the
1763 common flash structure for storing flash geometry.
1765 - CFG_FLASH_CFI_DRIVER
1766 This option also enables the building of the cfi_flash driver
1767 in the drivers directory
1769 - CFG_FLASH_QUIET_TEST
1770 If this option is defined, the common CFI flash doesn't
1771 print it's warning upon not recognized FLASH banks. This
1772 is useful, if some of the configured banks are only
1773 optionally available.
1775 - CFG_RX_ETH_BUFFER:
1776 Defines the number of ethernet receive buffers. On some
1777 ethernet controllers it is recommended to set this value
1778 to 8 or even higher (EEPRO100 or 405 EMAC), since all
1779 buffers can be full shortly after enabling the interface
1780 on high ethernet traffic.
1781 Defaults to 4 if not defined.
1783 The following definitions that deal with the placement and management
1784 of environment data (variable area); in general, we support the
1785 following configurations:
1787 - CFG_ENV_IS_IN_FLASH:
1789 Define this if the environment is in flash memory.
1791 a) The environment occupies one whole flash sector, which is
1792 "embedded" in the text segment with the U-Boot code. This
1793 happens usually with "bottom boot sector" or "top boot
1794 sector" type flash chips, which have several smaller
1795 sectors at the start or the end. For instance, such a
1796 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
1797 such a case you would place the environment in one of the
1798 4 kB sectors - with U-Boot code before and after it. With
1799 "top boot sector" type flash chips, you would put the
1800 environment in one of the last sectors, leaving a gap
1801 between U-Boot and the environment.
1805 Offset of environment data (variable area) to the
1806 beginning of flash memory; for instance, with bottom boot
1807 type flash chips the second sector can be used: the offset
1808 for this sector is given here.
1810 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE.
1814 This is just another way to specify the start address of
1815 the flash sector containing the environment (instead of
1818 - CFG_ENV_SECT_SIZE:
1820 Size of the sector containing the environment.
1823 b) Sometimes flash chips have few, equal sized, BIG sectors.
1824 In such a case you don't want to spend a whole sector for
1829 If you use this in combination with CFG_ENV_IS_IN_FLASH
1830 and CFG_ENV_SECT_SIZE, you can specify to use only a part
1831 of this flash sector for the environment. This saves
1832 memory for the RAM copy of the environment.
1834 It may also save flash memory if you decide to use this
1835 when your environment is "embedded" within U-Boot code,
1836 since then the remainder of the flash sector could be used
1837 for U-Boot code. It should be pointed out that this is
1838 STRONGLY DISCOURAGED from a robustness point of view:
1839 updating the environment in flash makes it always
1840 necessary to erase the WHOLE sector. If something goes
1841 wrong before the contents has been restored from a copy in
1842 RAM, your target system will be dead.
1844 - CFG_ENV_ADDR_REDUND
1847 These settings describe a second storage area used to hold
1848 a redundand copy of the environment data, so that there is
1849 a valid backup copy in case there is a power failure during
1850 a "saveenv" operation.
1852 BE CAREFUL! Any changes to the flash layout, and some changes to the
1853 source code will make it necessary to adapt <board>/u-boot.lds*
1857 - CFG_ENV_IS_IN_NVRAM:
1859 Define this if you have some non-volatile memory device
1860 (NVRAM, battery buffered SRAM) which you want to use for the
1866 These two #defines are used to determin the memory area you
1867 want to use for environment. It is assumed that this memory
1868 can just be read and written to, without any special
1871 BE CAREFUL! The first access to the environment happens quite early
1872 in U-Boot initalization (when we try to get the setting of for the
1873 console baudrate). You *MUST* have mappend your NVRAM area then, or
1876 Please note that even with NVRAM we still use a copy of the
1877 environment in RAM: we could work on NVRAM directly, but we want to
1878 keep settings there always unmodified except somebody uses "saveenv"
1879 to save the current settings.
1882 - CFG_ENV_IS_IN_EEPROM:
1884 Use this if you have an EEPROM or similar serial access
1885 device and a driver for it.
1890 These two #defines specify the offset and size of the
1891 environment area within the total memory of your EEPROM.
1893 - CFG_I2C_EEPROM_ADDR:
1894 If defined, specified the chip address of the EEPROM device.
1895 The default address is zero.
1897 - CFG_EEPROM_PAGE_WRITE_BITS:
1898 If defined, the number of bits used to address bytes in a
1899 single page in the EEPROM device. A 64 byte page, for example
1900 would require six bits.
1902 - CFG_EEPROM_PAGE_WRITE_DELAY_MS:
1903 If defined, the number of milliseconds to delay between
1904 page writes. The default is zero milliseconds.
1906 - CFG_I2C_EEPROM_ADDR_LEN:
1907 The length in bytes of the EEPROM memory array address. Note
1908 that this is NOT the chip address length!
1910 - CFG_I2C_EEPROM_ADDR_OVERFLOW:
1911 EEPROM chips that implement "address overflow" are ones
1912 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
1913 address and the extra bits end up in the "chip address" bit
1914 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
1917 Note that we consider the length of the address field to
1918 still be one byte because the extra address bits are hidden
1919 in the chip address.
1922 The size in bytes of the EEPROM device.
1925 - CFG_ENV_IS_IN_DATAFLASH:
1927 Define this if you have a DataFlash memory device which you
1928 want to use for the environment.
1934 These three #defines specify the offset and size of the
1935 environment area within the total memory of your DataFlash placed
1936 at the specified address.
1938 - CFG_ENV_IS_IN_NAND:
1940 Define this if you have a NAND device which you want to use
1941 for the environment.
1946 These two #defines specify the offset and size of the environment
1947 area within the first NAND device.
1949 - CFG_SPI_INIT_OFFSET
1951 Defines offset to the initial SPI buffer area in DPRAM. The
1952 area is used at an early stage (ROM part) if the environment
1953 is configured to reside in the SPI EEPROM: We need a 520 byte
1954 scratch DPRAM area. It is used between the two initialization
1955 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
1956 to be a good choice since it makes it far enough from the
1957 start of the data area as well as from the stack pointer.
1959 Please note that the environment is read-only as long as the monitor
1960 has been relocated to RAM and a RAM copy of the environment has been
1961 created; also, when using EEPROM you will have to use getenv_r()
1962 until then to read environment variables.
1964 The environment is protected by a CRC32 checksum. Before the monitor
1965 is relocated into RAM, as a result of a bad CRC you will be working
1966 with the compiled-in default environment - *silently*!!! [This is
1967 necessary, because the first environment variable we need is the
1968 "baudrate" setting for the console - if we have a bad CRC, we don't
1969 have any device yet where we could complain.]
1971 Note: once the monitor has been relocated, then it will complain if
1972 the default environment is used; a new CRC is computed as soon as you
1973 use the "saveenv" command to store a valid environment.
1975 - CFG_FAULT_ECHO_LINK_DOWN:
1976 Echo the inverted Ethernet link state to the fault LED.
1978 Note: If this option is active, then CFG_FAULT_MII_ADDR
1979 also needs to be defined.
1981 - CFG_FAULT_MII_ADDR:
1982 MII address of the PHY to check for the Ethernet link state.
1984 - CFG_64BIT_VSPRINTF:
1985 Makes vsprintf (and all *printf functions) support printing
1986 of 64bit values by using the L quantifier
1988 - CFG_64BIT_STRTOUL:
1989 Adds simple_strtoull that returns a 64bit value
1991 Low Level (hardware related) configuration options:
1992 ---------------------------------------------------
1994 - CFG_CACHELINE_SIZE:
1995 Cache Line Size of the CPU.
1998 Default address of the IMMR after system reset.
2000 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
2001 and RPXsuper) to be able to adjust the position of
2002 the IMMR register after a reset.
2004 - Floppy Disk Support:
2005 CFG_FDC_DRIVE_NUMBER
2007 the default drive number (default value 0)
2011 defines the spacing between fdc chipset registers
2016 defines the offset of register from address. It
2017 depends on which part of the data bus is connected to
2018 the fdc chipset. (default value 0)
2020 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and
2021 CFG_FDC_DRIVE_NUMBER are undefined, they take their
2024 if CFG_FDC_HW_INIT is defined, then the function
2025 fdc_hw_init() is called at the beginning of the FDC
2026 setup. fdc_hw_init() must be provided by the board
2027 source code. It is used to make hardware dependant
2030 - CFG_IMMR: Physical address of the Internal Memory.
2031 DO NOT CHANGE unless you know exactly what you're
2032 doing! (11-4) [MPC8xx/82xx systems only]
2034 - CFG_INIT_RAM_ADDR:
2036 Start address of memory area that can be used for
2037 initial data and stack; please note that this must be
2038 writable memory that is working WITHOUT special
2039 initialization, i. e. you CANNOT use normal RAM which
2040 will become available only after programming the
2041 memory controller and running certain initialization
2044 U-Boot uses the following memory types:
2045 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
2046 - MPC824X: data cache
2047 - PPC4xx: data cache
2049 - CFG_GBL_DATA_OFFSET:
2051 Offset of the initial data structure in the memory
2052 area defined by CFG_INIT_RAM_ADDR. Usually
2053 CFG_GBL_DATA_OFFSET is chosen such that the initial
2054 data is located at the end of the available space
2055 (sometimes written as (CFG_INIT_RAM_END -
2056 CFG_INIT_DATA_SIZE), and the initial stack is just
2057 below that area (growing from (CFG_INIT_RAM_ADDR +
2058 CFG_GBL_DATA_OFFSET) downward.
2061 On the MPC824X (or other systems that use the data
2062 cache for initial memory) the address chosen for
2063 CFG_INIT_RAM_ADDR is basically arbitrary - it must
2064 point to an otherwise UNUSED address space between
2065 the top of RAM and the start of the PCI space.
2067 - CFG_SIUMCR: SIU Module Configuration (11-6)
2069 - CFG_SYPCR: System Protection Control (11-9)
2071 - CFG_TBSCR: Time Base Status and Control (11-26)
2073 - CFG_PISCR: Periodic Interrupt Status and Control (11-31)
2075 - CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
2077 - CFG_SCCR: System Clock and reset Control Register (15-27)
2079 - CFG_OR_TIMING_SDRAM:
2083 periodic timer for refresh
2085 - CFG_DER: Debug Event Register (37-47)
2087 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM,
2088 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP,
2089 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM,
2091 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
2093 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
2094 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM,
2095 CFG_OR3_PRELIM, CFG_BR3_PRELIM:
2096 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
2098 - CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K,
2099 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL:
2100 Machine Mode Register and Memory Periodic Timer
2101 Prescaler definitions (SDRAM timing)
2103 - CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]:
2104 enable I2C microcode relocation patch (MPC8xx);
2105 define relocation offset in DPRAM [DSP2]
2107 - CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]:
2108 enable SPI microcode relocation patch (MPC8xx);
2109 define relocation offset in DPRAM [SCC4]
2112 Use OSCM clock mode on MBX8xx board. Be careful,
2113 wrong setting might damage your board. Read
2114 doc/README.MBX before setting this variable!
2116 - CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
2117 Offset of the bootmode word in DPRAM used by post
2118 (Power On Self Tests). This definition overrides
2119 #define'd default value in commproc.h resp.
2122 - CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB,
2123 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL,
2124 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS,
2125 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB,
2126 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
2127 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL,
2128 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE,
2129 CFG_POCMR2_MASK_ATTRIB: (MPC826x only)
2130 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set.
2132 - CONFIG_ETHER_ON_FEC[12]
2133 Define to enable FEC[12] on a 8xx series processor.
2135 - CONFIG_FEC[12]_PHY
2136 Define to the hardcoded PHY address which corresponds
2137 to the given FEC; i. e.
2138 #define CONFIG_FEC1_PHY 4
2139 means that the PHY with address 4 is connected to FEC1
2141 When set to -1, means to probe for first available.
2143 - CONFIG_FEC[12]_PHY_NORXERR
2144 The PHY does not have a RXERR line (RMII only).
2145 (so program the FEC to ignore it).
2148 Enable RMII mode for all FECs.
2149 Note that this is a global option, we can't
2150 have one FEC in standard MII mode and another in RMII mode.
2152 - CONFIG_CRC32_VERIFY
2153 Add a verify option to the crc32 command.
2156 => crc32 -v <address> <count> <crc32>
2158 Where address/count indicate a memory area
2159 and crc32 is the correct crc32 which the
2163 Add the "loopw" memory command. This only takes effect if
2164 the memory commands are activated globally (CFG_CMD_MEM).
2167 Add the "mdc" and "mwc" memory commands. These are cyclic
2172 This command will print 4 bytes (10,11,12,13) each 500 ms.
2174 => mwc.l 100 12345678 10
2175 This command will write 12345678 to address 100 all 10 ms.
2177 This only takes effect if the memory commands are activated
2178 globally (CFG_CMD_MEM).
2180 - CONFIG_SKIP_LOWLEVEL_INIT
2181 - CONFIG_SKIP_RELOCATE_UBOOT
2183 [ARM only] If these variables are defined, then
2184 certain low level initializations (like setting up
2185 the memory controller) are omitted and/or U-Boot does
2186 not relocate itself into RAM.
2187 Normally these variables MUST NOT be defined. The
2188 only exception is when U-Boot is loaded (to RAM) by
2189 some other boot loader or by a debugger which
2190 performs these intializations itself.
2193 Building the Software:
2194 ======================
2196 Building U-Boot has been tested in native PPC environments (on a
2197 PowerBook G3 running LinuxPPC 2000) and in cross environments
2198 (running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and
2201 If you are not using a native PPC environment, it is assumed that you
2202 have the GNU cross compiling tools available in your path and named
2203 with a prefix of "powerpc-linux-". If this is not the case, (e.g. if
2204 you are using Monta Vista's Hard Hat Linux CDK 1.2) you must change
2205 the definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU,
2208 CROSS_COMPILE = ppc_4xx-
2211 U-Boot is intended to be simple to build. After installing the
2212 sources you must configure U-Boot for one specific board type. This
2217 where "NAME_config" is the name of one of the existing
2218 configurations; the following names are supported:
2220 ADCIOP_config FPS860L_config omap730p2_config
2221 ADS860_config GEN860T_config pcu_e_config
2223 AR405_config GENIETV_config PIP405_config
2224 at91rm9200dk_config GTH_config QS823_config
2225 CANBT_config hermes_config QS850_config
2226 cmi_mpc5xx_config hymod_config QS860T_config
2227 cogent_common_config IP860_config RPXlite_config
2228 cogent_mpc8260_config IVML24_config RPXlite_DW_config
2229 cogent_mpc8xx_config IVMS8_config RPXsuper_config
2230 CPCI405_config JSE_config rsdproto_config
2231 CPCIISER4_config LANTEC_config Sandpoint8240_config
2232 csb272_config lwmon_config sbc8260_config
2233 CU824_config MBX860T_config sbc8560_33_config
2234 DUET_ADS_config MBX_config sbc8560_66_config
2235 EBONY_config MPC8260ADS_config SM850_config
2236 ELPT860_config MPC8540ADS_config SPD823TS_config
2237 ESTEEM192E_config MPC8540EVAL_config stxgp3_config
2238 ETX094_config MPC8560ADS_config SXNI855T_config
2239 FADS823_config NETVIA_config TQM823L_config
2240 FADS850SAR_config omap1510inn_config TQM850L_config
2241 FADS860T_config omap1610h2_config TQM855L_config
2242 FPS850L_config omap1610inn_config TQM860L_config
2243 omap5912osk_config walnut_config
2244 omap2420h4_config Yukon8220_config
2247 Note: for some board special configuration names may exist; check if
2248 additional information is available from the board vendor; for
2249 instance, the TQM823L systems are available without (standard)
2250 or with LCD support. You can select such additional "features"
2251 when chosing the configuration, i. e.
2254 - will configure for a plain TQM823L, i. e. no LCD support
2256 make TQM823L_LCD_config
2257 - will configure for a TQM823L with U-Boot console on LCD
2262 Finally, type "make all", and you should get some working U-Boot
2263 images ready for download to / installation on your system:
2265 - "u-boot.bin" is a raw binary image
2266 - "u-boot" is an image in ELF binary format
2267 - "u-boot.srec" is in Motorola S-Record format
2270 Please be aware that the Makefiles assume you are using GNU make, so
2271 for instance on NetBSD you might need to use "gmake" instead of
2275 If the system board that you have is not listed, then you will need
2276 to port U-Boot to your hardware platform. To do this, follow these
2279 1. Add a new configuration option for your board to the toplevel
2280 "Makefile" and to the "MAKEALL" script, using the existing
2281 entries as examples. Note that here and at many other places
2282 boards and other names are listed in alphabetical sort order. Please
2284 2. Create a new directory to hold your board specific code. Add any
2285 files you need. In your board directory, you will need at least
2286 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
2287 3. Create a new configuration file "include/configs/<board>.h" for
2289 3. If you're porting U-Boot to a new CPU, then also create a new
2290 directory to hold your CPU specific code. Add any files you need.
2291 4. Run "make <board>_config" with your new name.
2292 5. Type "make", and you should get a working "u-boot.srec" file
2293 to be installed on your target system.
2294 6. Debug and solve any problems that might arise.
2295 [Of course, this last step is much harder than it sounds.]
2298 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
2299 ==============================================================
2301 If you have modified U-Boot sources (for instance added a new board
2302 or support for new devices, a new CPU, etc.) you are expected to
2303 provide feedback to the other developers. The feedback normally takes
2304 the form of a "patch", i. e. a context diff against a certain (latest
2305 official or latest in CVS) version of U-Boot sources.
2307 But before you submit such a patch, please verify that your modifi-
2308 cation did not break existing code. At least make sure that *ALL* of
2309 the supported boards compile WITHOUT ANY compiler warnings. To do so,
2310 just run the "MAKEALL" script, which will configure and build U-Boot
2311 for ALL supported system. Be warned, this will take a while. You can
2312 select which (cross) compiler to use by passing a `CROSS_COMPILE'
2313 environment variable to the script, i. e. to use the cross tools from
2314 MontaVista's Hard Hat Linux you can type
2316 CROSS_COMPILE=ppc_8xx- MAKEALL
2318 or to build on a native PowerPC system you can type
2320 CROSS_COMPILE=' ' MAKEALL
2322 See also "U-Boot Porting Guide" below.
2325 Monitor Commands - Overview:
2326 ============================
2328 go - start application at address 'addr'
2329 run - run commands in an environment variable
2330 bootm - boot application image from memory
2331 bootp - boot image via network using BootP/TFTP protocol
2332 tftpboot- boot image via network using TFTP protocol
2333 and env variables "ipaddr" and "serverip"
2334 (and eventually "gatewayip")
2335 rarpboot- boot image via network using RARP/TFTP protocol
2336 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
2337 loads - load S-Record file over serial line
2338 loadb - load binary file over serial line (kermit mode)
2340 mm - memory modify (auto-incrementing)
2341 nm - memory modify (constant address)
2342 mw - memory write (fill)
2344 cmp - memory compare
2345 crc32 - checksum calculation
2346 imd - i2c memory display
2347 imm - i2c memory modify (auto-incrementing)
2348 inm - i2c memory modify (constant address)
2349 imw - i2c memory write (fill)
2350 icrc32 - i2c checksum calculation
2351 iprobe - probe to discover valid I2C chip addresses
2352 iloop - infinite loop on address range
2353 isdram - print SDRAM configuration information
2354 sspi - SPI utility commands
2355 base - print or set address offset
2356 printenv- print environment variables
2357 setenv - set environment variables
2358 saveenv - save environment variables to persistent storage
2359 protect - enable or disable FLASH write protection
2360 erase - erase FLASH memory
2361 flinfo - print FLASH memory information
2362 bdinfo - print Board Info structure
2363 iminfo - print header information for application image
2364 coninfo - print console devices and informations
2365 ide - IDE sub-system
2366 loop - infinite loop on address range
2367 loopw - infinite write loop on address range
2368 mtest - simple RAM test
2369 icache - enable or disable instruction cache
2370 dcache - enable or disable data cache
2371 reset - Perform RESET of the CPU
2372 echo - echo args to console
2373 version - print monitor version
2374 help - print online help
2375 ? - alias for 'help'
2378 Monitor Commands - Detailed Description:
2379 ========================================
2383 For now: just type "help <command>".
2386 Environment Variables:
2387 ======================
2389 U-Boot supports user configuration using Environment Variables which
2390 can be made persistent by saving to Flash memory.
2392 Environment Variables are set using "setenv", printed using
2393 "printenv", and saved to Flash using "saveenv". Using "setenv"
2394 without a value can be used to delete a variable from the
2395 environment. As long as you don't save the environment you are
2396 working with an in-memory copy. In case the Flash area containing the
2397 environment is erased by accident, a default environment is provided.
2399 Some configuration options can be set using Environment Variables:
2401 baudrate - see CONFIG_BAUDRATE
2403 bootdelay - see CONFIG_BOOTDELAY
2405 bootcmd - see CONFIG_BOOTCOMMAND
2407 bootargs - Boot arguments when booting an RTOS image
2409 bootfile - Name of the image to load with TFTP
2411 autoload - if set to "no" (any string beginning with 'n'),
2412 "bootp" will just load perform a lookup of the
2413 configuration from the BOOTP server, but not try to
2414 load any image using TFTP
2416 autostart - if set to "yes", an image loaded using the "bootp",
2417 "rarpboot", "tftpboot" or "diskboot" commands will
2418 be automatically started (by internally calling
2421 If set to "no", a standalone image passed to the
2422 "bootm" command will be copied to the load address
2423 (and eventually uncompressed), but NOT be started.
2424 This can be used to load and uncompress arbitrary
2427 i2cfast - (PPC405GP|PPC405EP only)
2428 if set to 'y' configures Linux I2C driver for fast
2429 mode (400kHZ). This environment variable is used in
2430 initialization code. So, for changes to be effective
2431 it must be saved and board must be reset.
2433 initrd_high - restrict positioning of initrd images:
2434 If this variable is not set, initrd images will be
2435 copied to the highest possible address in RAM; this
2436 is usually what you want since it allows for
2437 maximum initrd size. If for some reason you want to
2438 make sure that the initrd image is loaded below the
2439 CFG_BOOTMAPSZ limit, you can set this environment
2440 variable to a value of "no" or "off" or "0".
2441 Alternatively, you can set it to a maximum upper
2442 address to use (U-Boot will still check that it
2443 does not overwrite the U-Boot stack and data).
2445 For instance, when you have a system with 16 MB
2446 RAM, and want to reserve 4 MB from use by Linux,
2447 you can do this by adding "mem=12M" to the value of
2448 the "bootargs" variable. However, now you must make
2449 sure that the initrd image is placed in the first
2450 12 MB as well - this can be done with
2452 setenv initrd_high 00c00000
2454 If you set initrd_high to 0xFFFFFFFF, this is an
2455 indication to U-Boot that all addresses are legal
2456 for the Linux kernel, including addresses in flash
2457 memory. In this case U-Boot will NOT COPY the
2458 ramdisk at all. This may be useful to reduce the
2459 boot time on your system, but requires that this
2460 feature is supported by your Linux kernel.
2462 ipaddr - IP address; needed for tftpboot command
2464 loadaddr - Default load address for commands like "bootp",
2465 "rarpboot", "tftpboot", "loadb" or "diskboot"
2467 loads_echo - see CONFIG_LOADS_ECHO
2469 serverip - TFTP server IP address; needed for tftpboot command
2471 bootretry - see CONFIG_BOOT_RETRY_TIME
2473 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
2475 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
2477 ethprime - When CONFIG_NET_MULTI is enabled controls which
2478 interface is used first.
2480 ethact - When CONFIG_NET_MULTI is enabled controls which
2481 interface is currently active. For example you
2482 can do the following
2484 => setenv ethact FEC ETHERNET
2485 => ping 192.168.0.1 # traffic sent on FEC ETHERNET
2486 => setenv ethact SCC ETHERNET
2487 => ping 10.0.0.1 # traffic sent on SCC ETHERNET
2489 netretry - When set to "no" each network operation will
2490 either succeed or fail without retrying.
2491 When set to "once" the network operation will
2492 fail when all the available network interfaces
2493 are tried once without success.
2494 Useful on scripts which control the retry operation
2497 tftpsrcport - If this is set, the value is used for TFTP's
2500 tftpdstport - If this is set, the value is used for TFTP's UDP
2501 destination port instead of the Well Know Port 69.
2503 vlan - When set to a value < 4095 the traffic over
2504 ethernet is encapsulated/received over 802.1q
2507 The following environment variables may be used and automatically
2508 updated by the network boot commands ("bootp" and "rarpboot"),
2509 depending the information provided by your boot server:
2511 bootfile - see above
2512 dnsip - IP address of your Domain Name Server
2513 dnsip2 - IP address of your secondary Domain Name Server
2514 gatewayip - IP address of the Gateway (Router) to use
2515 hostname - Target hostname
2517 netmask - Subnet Mask
2518 rootpath - Pathname of the root filesystem on the NFS server
2519 serverip - see above
2522 There are two special Environment Variables:
2524 serial# - contains hardware identification information such
2525 as type string and/or serial number
2526 ethaddr - Ethernet address
2528 These variables can be set only once (usually during manufacturing of
2529 the board). U-Boot refuses to delete or overwrite these variables
2530 once they have been set once.
2533 Further special Environment Variables:
2535 ver - Contains the U-Boot version string as printed
2536 with the "version" command. This variable is
2537 readonly (see CONFIG_VERSION_VARIABLE).
2540 Please note that changes to some configuration parameters may take
2541 only effect after the next boot (yes, that's just like Windoze :-).
2544 Command Line Parsing:
2545 =====================
2547 There are two different command line parsers available with U-Boot:
2548 the old "simple" one, and the much more powerful "hush" shell:
2550 Old, simple command line parser:
2551 --------------------------------
2553 - supports environment variables (through setenv / saveenv commands)
2554 - several commands on one line, separated by ';'
2555 - variable substitution using "... ${name} ..." syntax
2556 - special characters ('$', ';') can be escaped by prefixing with '\',
2558 setenv bootcmd bootm \${address}
2559 - You can also escape text by enclosing in single apostrophes, for example:
2560 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
2565 - similar to Bourne shell, with control structures like
2566 if...then...else...fi, for...do...done; while...do...done,
2567 until...do...done, ...
2568 - supports environment ("global") variables (through setenv / saveenv
2569 commands) and local shell variables (through standard shell syntax
2570 "name=value"); only environment variables can be used with "run"
2576 (1) If a command line (or an environment variable executed by a "run"
2577 command) contains several commands separated by semicolon, and
2578 one of these commands fails, then the remaining commands will be
2581 (2) If you execute several variables with one call to run (i. e.
2582 calling run with a list af variables as arguments), any failing
2583 command will cause "run" to terminate, i. e. the remaining
2584 variables are not executed.
2586 Note for Redundant Ethernet Interfaces:
2587 =======================================
2589 Some boards come with redundant ethernet interfaces; U-Boot supports
2590 such configurations and is capable of automatic selection of a
2591 "working" interface when needed. MAC assignment works as follows:
2593 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
2594 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
2595 "eth1addr" (=>eth1), "eth2addr", ...
2597 If the network interface stores some valid MAC address (for instance
2598 in SROM), this is used as default address if there is NO correspon-
2599 ding setting in the environment; if the corresponding environment
2600 variable is set, this overrides the settings in the card; that means:
2602 o If the SROM has a valid MAC address, and there is no address in the
2603 environment, the SROM's address is used.
2605 o If there is no valid address in the SROM, and a definition in the
2606 environment exists, then the value from the environment variable is
2609 o If both the SROM and the environment contain a MAC address, and
2610 both addresses are the same, this MAC address is used.
2612 o If both the SROM and the environment contain a MAC address, and the
2613 addresses differ, the value from the environment is used and a
2616 o If neither SROM nor the environment contain a MAC address, an error
2623 The "boot" commands of this monitor operate on "image" files which
2624 can be basicly anything, preceeded by a special header; see the
2625 definitions in include/image.h for details; basicly, the header
2626 defines the following image properties:
2628 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
2629 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
2630 LynxOS, pSOS, QNX, RTEMS, ARTOS;
2631 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS).
2632 * Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
2633 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
2634 Currently supported: ARM, Intel x86, MIPS, NIOS, PowerPC).
2635 * Compression Type (uncompressed, gzip, bzip2)
2641 The header is marked by a special Magic Number, and both the header
2642 and the data portions of the image are secured against corruption by
2649 Although U-Boot should support any OS or standalone application
2650 easily, the main focus has always been on Linux during the design of
2653 U-Boot includes many features that so far have been part of some
2654 special "boot loader" code within the Linux kernel. Also, any
2655 "initrd" images to be used are no longer part of one big Linux image;
2656 instead, kernel and "initrd" are separate images. This implementation
2657 serves several purposes:
2659 - the same features can be used for other OS or standalone
2660 applications (for instance: using compressed images to reduce the
2661 Flash memory footprint)
2663 - it becomes much easier to port new Linux kernel versions because
2664 lots of low-level, hardware dependent stuff are done by U-Boot
2666 - the same Linux kernel image can now be used with different "initrd"
2667 images; of course this also means that different kernel images can
2668 be run with the same "initrd". This makes testing easier (you don't
2669 have to build a new "zImage.initrd" Linux image when you just
2670 change a file in your "initrd"). Also, a field-upgrade of the
2671 software is easier now.
2677 Porting Linux to U-Boot based systems:
2678 ---------------------------------------
2680 U-Boot cannot save you from doing all the necessary modifications to
2681 configure the Linux device drivers for use with your target hardware
2682 (no, we don't intend to provide a full virtual machine interface to
2685 But now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
2687 Just make sure your machine specific header file (for instance
2688 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
2689 Information structure as we define in include/u-boot.h, and make
2690 sure that your definition of IMAP_ADDR uses the same value as your
2691 U-Boot configuration in CFG_IMMR.
2694 Configuring the Linux kernel:
2695 -----------------------------
2697 No specific requirements for U-Boot. Make sure you have some root
2698 device (initial ramdisk, NFS) for your target system.
2701 Building a Linux Image:
2702 -----------------------
2704 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
2705 not used. If you use recent kernel source, a new build target
2706 "uImage" will exist which automatically builds an image usable by
2707 U-Boot. Most older kernels also have support for a "pImage" target,
2708 which was introduced for our predecessor project PPCBoot and uses a
2709 100% compatible format.
2718 The "uImage" build target uses a special tool (in 'tools/mkimage') to
2719 encapsulate a compressed Linux kernel image with header information,
2720 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
2722 * build a standard "vmlinux" kernel image (in ELF binary format):
2724 * convert the kernel into a raw binary image:
2726 ${CROSS_COMPILE}-objcopy -O binary \
2727 -R .note -R .comment \
2728 -S vmlinux linux.bin
2730 * compress the binary image:
2734 * package compressed binary image for U-Boot:
2736 mkimage -A ppc -O linux -T kernel -C gzip \
2737 -a 0 -e 0 -n "Linux Kernel Image" \
2738 -d linux.bin.gz uImage
2741 The "mkimage" tool can also be used to create ramdisk images for use
2742 with U-Boot, either separated from the Linux kernel image, or
2743 combined into one file. "mkimage" encapsulates the images with a 64
2744 byte header containing information about target architecture,
2745 operating system, image type, compression method, entry points, time
2746 stamp, CRC32 checksums, etc.
2748 "mkimage" can be called in two ways: to verify existing images and
2749 print the header information, or to build new images.
2751 In the first form (with "-l" option) mkimage lists the information
2752 contained in the header of an existing U-Boot image; this includes
2753 checksum verification:
2755 tools/mkimage -l image
2756 -l ==> list image header information
2758 The second form (with "-d" option) is used to build a U-Boot image
2759 from a "data file" which is used as image payload:
2761 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
2762 -n name -d data_file image
2763 -A ==> set architecture to 'arch'
2764 -O ==> set operating system to 'os'
2765 -T ==> set image type to 'type'
2766 -C ==> set compression type 'comp'
2767 -a ==> set load address to 'addr' (hex)
2768 -e ==> set entry point to 'ep' (hex)
2769 -n ==> set image name to 'name'
2770 -d ==> use image data from 'datafile'
2772 Right now, all Linux kernels for PowerPC systems use the same load
2773 address (0x00000000), but the entry point address depends on the
2776 - 2.2.x kernels have the entry point at 0x0000000C,
2777 - 2.3.x and later kernels have the entry point at 0x00000000.
2779 So a typical call to build a U-Boot image would read:
2781 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2782 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
2783 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
2784 > examples/uImage.TQM850L
2785 Image Name: 2.4.4 kernel for TQM850L
2786 Created: Wed Jul 19 02:34:59 2000
2787 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2788 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2789 Load Address: 0x00000000
2790 Entry Point: 0x00000000
2792 To verify the contents of the image (or check for corruption):
2794 -> tools/mkimage -l examples/uImage.TQM850L
2795 Image Name: 2.4.4 kernel for TQM850L
2796 Created: Wed Jul 19 02:34:59 2000
2797 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2798 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2799 Load Address: 0x00000000
2800 Entry Point: 0x00000000
2802 NOTE: for embedded systems where boot time is critical you can trade
2803 speed for memory and install an UNCOMPRESSED image instead: this
2804 needs more space in Flash, but boots much faster since it does not
2805 need to be uncompressed:
2807 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
2808 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2809 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
2810 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
2811 > examples/uImage.TQM850L-uncompressed
2812 Image Name: 2.4.4 kernel for TQM850L
2813 Created: Wed Jul 19 02:34:59 2000
2814 Image Type: PowerPC Linux Kernel Image (uncompressed)
2815 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
2816 Load Address: 0x00000000
2817 Entry Point: 0x00000000
2820 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
2821 when your kernel is intended to use an initial ramdisk:
2823 -> tools/mkimage -n 'Simple Ramdisk Image' \
2824 > -A ppc -O linux -T ramdisk -C gzip \
2825 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
2826 Image Name: Simple Ramdisk Image
2827 Created: Wed Jan 12 14:01:50 2000
2828 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2829 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
2830 Load Address: 0x00000000
2831 Entry Point: 0x00000000
2834 Installing a Linux Image:
2835 -------------------------
2837 To downloading a U-Boot image over the serial (console) interface,
2838 you must convert the image to S-Record format:
2840 objcopy -I binary -O srec examples/image examples/image.srec
2842 The 'objcopy' does not understand the information in the U-Boot
2843 image header, so the resulting S-Record file will be relative to
2844 address 0x00000000. To load it to a given address, you need to
2845 specify the target address as 'offset' parameter with the 'loads'
2848 Example: install the image to address 0x40100000 (which on the
2849 TQM8xxL is in the first Flash bank):
2851 => erase 40100000 401FFFFF
2857 ## Ready for S-Record download ...
2858 ~>examples/image.srec
2859 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
2861 15989 15990 15991 15992
2862 [file transfer complete]
2864 ## Start Addr = 0x00000000
2867 You can check the success of the download using the 'iminfo' command;
2868 this includes a checksum verification so you can be sure no data
2869 corruption happened:
2873 ## Checking Image at 40100000 ...
2874 Image Name: 2.2.13 for initrd on TQM850L
2875 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2876 Data Size: 335725 Bytes = 327 kB = 0 MB
2877 Load Address: 00000000
2878 Entry Point: 0000000c
2879 Verifying Checksum ... OK
2885 The "bootm" command is used to boot an application that is stored in
2886 memory (RAM or Flash). In case of a Linux kernel image, the contents
2887 of the "bootargs" environment variable is passed to the kernel as
2888 parameters. You can check and modify this variable using the
2889 "printenv" and "setenv" commands:
2892 => printenv bootargs
2893 bootargs=root=/dev/ram
2895 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2897 => printenv bootargs
2898 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2901 ## Booting Linux kernel at 40020000 ...
2902 Image Name: 2.2.13 for NFS on TQM850L
2903 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2904 Data Size: 381681 Bytes = 372 kB = 0 MB
2905 Load Address: 00000000
2906 Entry Point: 0000000c
2907 Verifying Checksum ... OK
2908 Uncompressing Kernel Image ... OK
2909 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
2910 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2911 time_init: decrementer frequency = 187500000/60
2912 Calibrating delay loop... 49.77 BogoMIPS
2913 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
2916 If you want to boot a Linux kernel with initial ram disk, you pass
2917 the memory addresses of both the kernel and the initrd image (PPBCOOT
2918 format!) to the "bootm" command:
2920 => imi 40100000 40200000
2922 ## Checking Image at 40100000 ...
2923 Image Name: 2.2.13 for initrd on TQM850L
2924 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2925 Data Size: 335725 Bytes = 327 kB = 0 MB
2926 Load Address: 00000000
2927 Entry Point: 0000000c
2928 Verifying Checksum ... OK
2930 ## Checking Image at 40200000 ...
2931 Image Name: Simple Ramdisk Image
2932 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2933 Data Size: 566530 Bytes = 553 kB = 0 MB
2934 Load Address: 00000000
2935 Entry Point: 00000000
2936 Verifying Checksum ... OK
2938 => bootm 40100000 40200000
2939 ## Booting Linux kernel at 40100000 ...
2940 Image Name: 2.2.13 for initrd on TQM850L
2941 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2942 Data Size: 335725 Bytes = 327 kB = 0 MB
2943 Load Address: 00000000
2944 Entry Point: 0000000c
2945 Verifying Checksum ... OK
2946 Uncompressing Kernel Image ... OK
2947 ## Loading RAMDisk Image at 40200000 ...
2948 Image Name: Simple Ramdisk Image
2949 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2950 Data Size: 566530 Bytes = 553 kB = 0 MB
2951 Load Address: 00000000
2952 Entry Point: 00000000
2953 Verifying Checksum ... OK
2954 Loading Ramdisk ... OK
2955 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
2956 Boot arguments: root=/dev/ram
2957 time_init: decrementer frequency = 187500000/60
2958 Calibrating delay loop... 49.77 BogoMIPS
2960 RAMDISK: Compressed image found at block 0
2961 VFS: Mounted root (ext2 filesystem).
2965 More About U-Boot Image Types:
2966 ------------------------------
2968 U-Boot supports the following image types:
2970 "Standalone Programs" are directly runnable in the environment
2971 provided by U-Boot; it is expected that (if they behave
2972 well) you can continue to work in U-Boot after return from
2973 the Standalone Program.
2974 "OS Kernel Images" are usually images of some Embedded OS which
2975 will take over control completely. Usually these programs
2976 will install their own set of exception handlers, device
2977 drivers, set up the MMU, etc. - this means, that you cannot
2978 expect to re-enter U-Boot except by resetting the CPU.
2979 "RAMDisk Images" are more or less just data blocks, and their
2980 parameters (address, size) are passed to an OS kernel that is
2982 "Multi-File Images" contain several images, typically an OS
2983 (Linux) kernel image and one or more data images like
2984 RAMDisks. This construct is useful for instance when you want
2985 to boot over the network using BOOTP etc., where the boot
2986 server provides just a single image file, but you want to get
2987 for instance an OS kernel and a RAMDisk image.
2989 "Multi-File Images" start with a list of image sizes, each
2990 image size (in bytes) specified by an "uint32_t" in network
2991 byte order. This list is terminated by an "(uint32_t)0".
2992 Immediately after the terminating 0 follow the images, one by
2993 one, all aligned on "uint32_t" boundaries (size rounded up to
2994 a multiple of 4 bytes).
2996 "Firmware Images" are binary images containing firmware (like
2997 U-Boot or FPGA images) which usually will be programmed to
3000 "Script files" are command sequences that will be executed by
3001 U-Boot's command interpreter; this feature is especially
3002 useful when you configure U-Boot to use a real shell (hush)
3003 as command interpreter.
3009 One of the features of U-Boot is that you can dynamically load and
3010 run "standalone" applications, which can use some resources of
3011 U-Boot like console I/O functions or interrupt services.
3013 Two simple examples are included with the sources:
3018 'examples/hello_world.c' contains a small "Hello World" Demo
3019 application; it is automatically compiled when you build U-Boot.
3020 It's configured to run at address 0x00040004, so you can play with it
3024 ## Ready for S-Record download ...
3025 ~>examples/hello_world.srec
3026 1 2 3 4 5 6 7 8 9 10 11 ...
3027 [file transfer complete]
3029 ## Start Addr = 0x00040004
3031 => go 40004 Hello World! This is a test.
3032 ## Starting application at 0x00040004 ...
3043 Hit any key to exit ...
3045 ## Application terminated, rc = 0x0
3047 Another example, which demonstrates how to register a CPM interrupt
3048 handler with the U-Boot code, can be found in 'examples/timer.c'.
3049 Here, a CPM timer is set up to generate an interrupt every second.
3050 The interrupt service routine is trivial, just printing a '.'
3051 character, but this is just a demo program. The application can be
3052 controlled by the following keys:
3054 ? - print current values og the CPM Timer registers
3055 b - enable interrupts and start timer
3056 e - stop timer and disable interrupts
3057 q - quit application
3060 ## Ready for S-Record download ...
3061 ~>examples/timer.srec
3062 1 2 3 4 5 6 7 8 9 10 11 ...
3063 [file transfer complete]
3065 ## Start Addr = 0x00040004
3068 ## Starting application at 0x00040004 ...
3071 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
3074 [q, b, e, ?] Set interval 1000000 us
3077 [q, b, e, ?] ........
3078 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
3081 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
3084 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
3087 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
3089 [q, b, e, ?] ...Stopping timer
3091 [q, b, e, ?] ## Application terminated, rc = 0x0
3097 Over time, many people have reported problems when trying to use the
3098 "minicom" terminal emulation program for serial download. I (wd)
3099 consider minicom to be broken, and recommend not to use it. Under
3100 Unix, I recommend to use C-Kermit for general purpose use (and
3101 especially for kermit binary protocol download ("loadb" command), and
3102 use "cu" for S-Record download ("loads" command).
3104 Nevertheless, if you absolutely want to use it try adding this
3105 configuration to your "File transfer protocols" section:
3107 Name Program Name U/D FullScr IO-Red. Multi
3108 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
3109 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
3115 Starting at version 0.9.2, U-Boot supports NetBSD both as host
3116 (build U-Boot) and target system (boots NetBSD/mpc8xx).
3118 Building requires a cross environment; it is known to work on
3119 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
3120 need gmake since the Makefiles are not compatible with BSD make).
3121 Note that the cross-powerpc package does not install include files;
3122 attempting to build U-Boot will fail because <machine/ansi.h> is
3123 missing. This file has to be installed and patched manually:
3125 # cd /usr/pkg/cross/powerpc-netbsd/include
3127 # ln -s powerpc machine
3128 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
3129 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
3131 Native builds *don't* work due to incompatibilities between native
3132 and U-Boot include files.
3134 Booting assumes that (the first part of) the image booted is a
3135 stage-2 loader which in turn loads and then invokes the kernel
3136 proper. Loader sources will eventually appear in the NetBSD source
3137 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
3138 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
3141 Implementation Internals:
3142 =========================
3144 The following is not intended to be a complete description of every
3145 implementation detail. However, it should help to understand the
3146 inner workings of U-Boot and make it easier to port it to custom
3150 Initial Stack, Global Data:
3151 ---------------------------
3153 The implementation of U-Boot is complicated by the fact that U-Boot
3154 starts running out of ROM (flash memory), usually without access to
3155 system RAM (because the memory controller is not initialized yet).
3156 This means that we don't have writable Data or BSS segments, and BSS
3157 is not initialized as zero. To be able to get a C environment working
3158 at all, we have to allocate at least a minimal stack. Implementation
3159 options for this are defined and restricted by the CPU used: Some CPU
3160 models provide on-chip memory (like the IMMR area on MPC8xx and
3161 MPC826x processors), on others (parts of) the data cache can be
3162 locked as (mis-) used as memory, etc.
3164 Chris Hallinan posted a good summary of these issues to the
3165 u-boot-users mailing list:
3167 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
3168 From: "Chris Hallinan" <clh@net1plus.com>
3169 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
3172 Correct me if I'm wrong, folks, but the way I understand it
3173 is this: Using DCACHE as initial RAM for Stack, etc, does not
3174 require any physical RAM backing up the cache. The cleverness
3175 is that the cache is being used as a temporary supply of
3176 necessary storage before the SDRAM controller is setup. It's
3177 beyond the scope of this list to expain the details, but you
3178 can see how this works by studying the cache architecture and
3179 operation in the architecture and processor-specific manuals.
3181 OCM is On Chip Memory, which I believe the 405GP has 4K. It
3182 is another option for the system designer to use as an
3183 initial stack/ram area prior to SDRAM being available. Either
3184 option should work for you. Using CS 4 should be fine if your
3185 board designers haven't used it for something that would
3186 cause you grief during the initial boot! It is frequently not
3189 CFG_INIT_RAM_ADDR should be somewhere that won't interfere
3190 with your processor/board/system design. The default value
3191 you will find in any recent u-boot distribution in
3192 walnut.h should work for you. I'd set it to a value larger
3193 than your SDRAM module. If you have a 64MB SDRAM module, set
3194 it above 400_0000. Just make sure your board has no resources
3195 that are supposed to respond to that address! That code in
3196 start.S has been around a while and should work as is when
3197 you get the config right.
3202 It is essential to remember this, since it has some impact on the C
3203 code for the initialization procedures:
3205 * Initialized global data (data segment) is read-only. Do not attempt
3208 * Do not use any unitialized global data (or implicitely initialized
3209 as zero data - BSS segment) at all - this is undefined, initiali-
3210 zation is performed later (when relocating to RAM).
3212 * Stack space is very limited. Avoid big data buffers or things like
3215 Having only the stack as writable memory limits means we cannot use
3216 normal global data to share information beween the code. But it
3217 turned out that the implementation of U-Boot can be greatly
3218 simplified by making a global data structure (gd_t) available to all
3219 functions. We could pass a pointer to this data as argument to _all_
3220 functions, but this would bloat the code. Instead we use a feature of
3221 the GCC compiler (Global Register Variables) to share the data: we
3222 place a pointer (gd) to the global data into a register which we
3223 reserve for this purpose.
3225 When choosing a register for such a purpose we are restricted by the
3226 relevant (E)ABI specifications for the current architecture, and by
3227 GCC's implementation.
3229 For PowerPC, the following registers have specific use:
3232 R3-R4: parameter passing and return values
3233 R5-R10: parameter passing
3234 R13: small data area pointer
3238 (U-Boot also uses R14 as internal GOT pointer.)
3240 ==> U-Boot will use R29 to hold a pointer to the global data
3242 Note: on PPC, we could use a static initializer (since the
3243 address of the global data structure is known at compile time),
3244 but it turned out that reserving a register results in somewhat
3245 smaller code - although the code savings are not that big (on
3246 average for all boards 752 bytes for the whole U-Boot image,
3247 624 text + 127 data).
3249 On ARM, the following registers are used:
3251 R0: function argument word/integer result
3252 R1-R3: function argument word
3254 R10: stack limit (used only if stack checking if enabled)
3255 R11: argument (frame) pointer
3256 R12: temporary workspace
3259 R15: program counter
3261 ==> U-Boot will use R8 to hold a pointer to the global data
3267 U-Boot runs in system state and uses physical addresses, i.e. the
3268 MMU is not used either for address mapping nor for memory protection.
3270 The available memory is mapped to fixed addresses using the memory
3271 controller. In this process, a contiguous block is formed for each
3272 memory type (Flash, SDRAM, SRAM), even when it consists of several
3273 physical memory banks.
3275 U-Boot is installed in the first 128 kB of the first Flash bank (on
3276 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
3277 booting and sizing and initializing DRAM, the code relocates itself
3278 to the upper end of DRAM. Immediately below the U-Boot code some
3279 memory is reserved for use by malloc() [see CFG_MALLOC_LEN
3280 configuration setting]. Below that, a structure with global Board
3281 Info data is placed, followed by the stack (growing downward).
3283 Additionally, some exception handler code is copied to the low 8 kB
3284 of DRAM (0x00000000 ... 0x00001FFF).
3286 So a typical memory configuration with 16 MB of DRAM could look like
3289 0x0000 0000 Exception Vector code
3292 0x0000 2000 Free for Application Use
3298 0x00FB FF20 Monitor Stack (Growing downward)
3299 0x00FB FFAC Board Info Data and permanent copy of global data
3300 0x00FC 0000 Malloc Arena
3303 0x00FE 0000 RAM Copy of Monitor Code
3304 ... eventually: LCD or video framebuffer
3305 ... eventually: pRAM (Protected RAM - unchanged by reset)
3306 0x00FF FFFF [End of RAM]
3309 System Initialization:
3310 ----------------------
3312 In the reset configuration, U-Boot starts at the reset entry point
3313 (on most PowerPC systens at address 0x00000100). Because of the reset
3314 configuration for CS0# this is a mirror of the onboard Flash memory.
3315 To be able to re-map memory U-Boot then jumps to its link address.
3316 To be able to implement the initialization code in C, a (small!)
3317 initial stack is set up in the internal Dual Ported RAM (in case CPUs
3318 which provide such a feature like MPC8xx or MPC8260), or in a locked
3319 part of the data cache. After that, U-Boot initializes the CPU core,
3320 the caches and the SIU.
3322 Next, all (potentially) available memory banks are mapped using a
3323 preliminary mapping. For example, we put them on 512 MB boundaries
3324 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
3325 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
3326 programmed for SDRAM access. Using the temporary configuration, a
3327 simple memory test is run that determines the size of the SDRAM
3330 When there is more than one SDRAM bank, and the banks are of
3331 different size, the largest is mapped first. For equal size, the first
3332 bank (CS2#) is mapped first. The first mapping is always for address
3333 0x00000000, with any additional banks following immediately to create
3334 contiguous memory starting from 0.
3336 Then, the monitor installs itself at the upper end of the SDRAM area
3337 and allocates memory for use by malloc() and for the global Board
3338 Info data; also, the exception vector code is copied to the low RAM
3339 pages, and the final stack is set up.
3341 Only after this relocation will you have a "normal" C environment;
3342 until that you are restricted in several ways, mostly because you are
3343 running from ROM, and because the code will have to be relocated to a
3347 U-Boot Porting Guide:
3348 ----------------------
3350 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
3354 int main (int argc, char *argv[])
3356 sighandler_t no_more_time;
3358 signal (SIGALRM, no_more_time);
3359 alarm (PROJECT_DEADLINE - toSec (3 * WEEK));
3361 if (available_money > available_manpower) {
3362 pay consultant to port U-Boot;
3366 Download latest U-Boot source;
3368 Subscribe to u-boot-users mailing list;
3371 email ("Hi, I am new to U-Boot, how do I get started?");
3375 Read the README file in the top level directory;
3376 Read http://www.denx.de/twiki/bin/view/DULG/Manual ;
3377 Read the source, Luke;
3380 if (available_money > toLocalCurrency ($2500)) {
3383 Add a lot of aggravation and time;
3386 Create your own board support subdirectory;
3388 Create your own board config file;
3392 Add / modify source code;
3396 email ("Hi, I am having problems...");
3398 Send patch file to Wolfgang;
3403 void no_more_time (int sig)
3412 All contributions to U-Boot should conform to the Linux kernel
3413 coding style; see the file "Documentation/CodingStyle" in your Linux
3414 kernel source directory.
3416 Please note that U-Boot is implemented in C (and to some small parts
3417 in Assembler); no C++ is used, so please do not use C++ style
3418 comments (//) in your code.
3420 Please also stick to the following formatting rules:
3421 - remove any trailing white space
3422 - use TAB characters for indentation, not spaces
3423 - make sure NOT to use DOS '\r\n' line feeds
3424 - do not add more than 2 empty lines to source files
3425 - do not add trailing empty lines to source files
3427 Submissions which do not conform to the standards may be returned
3428 with a request to reformat the changes.
3434 Since the number of patches for U-Boot is growing, we need to
3435 establish some rules. Submissions which do not conform to these rules
3436 may be rejected, even when they contain important and valuable stuff.
3438 Patches shall be sent to the u-boot-users mailing list.
3440 When you send a patch, please include the following information with
3443 * For bug fixes: a description of the bug and how your patch fixes
3444 this bug. Please try to include a way of demonstrating that the
3445 patch actually fixes something.
3447 * For new features: a description of the feature and your
3450 * A CHANGELOG entry as plaintext (separate from the patch)
3452 * For major contributions, your entry to the CREDITS file
3454 * When you add support for a new board, don't forget to add this
3455 board to the MAKEALL script, too.
3457 * If your patch adds new configuration options, don't forget to
3458 document these in the README file.
3460 * The patch itself. If you are accessing the CVS repository use "cvs
3461 update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your
3462 version of diff does not support these options, then get the latest
3463 version of GNU diff.
3465 The current directory when running this command shall be the top
3466 level directory of the U-Boot source tree, or it's parent directory
3467 (i. e. please make sure that your patch includes sufficient
3468 directory information for the affected files).
3470 We accept patches as plain text, MIME attachments or as uuencoded
3473 * If one logical set of modifications affects or creates several
3474 files, all these changes shall be submitted in a SINGLE patch file.
3476 * Changesets that contain different, unrelated modifications shall be
3477 submitted as SEPARATE patches, one patch per changeset.
3482 * Before sending the patch, run the MAKEALL script on your patched
3483 source tree and make sure that no errors or warnings are reported
3484 for any of the boards.
3486 * Keep your modifications to the necessary minimum: A patch
3487 containing several unrelated changes or arbitrary reformats will be
3488 returned with a request to re-formatting / split it.
3490 * If you modify existing code, make sure that your new code does not
3491 add to the memory footprint of the code ;-) Small is beautiful!
3492 When adding new features, these should compile conditionally only
3493 (using #ifdef), and the resulting code with the new feature
3494 disabled must not need more memory than the old code without your
3497 * Remember that there is a size limit of 40 kB per message on the
3498 u-boot-users mailing list. Compression may help.
projects / u-boot / blob