1 #
2 # (C) Copyright 2000 - 2012
3 # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4 #
5 # See file CREDITS for list of people who contributed to this
6 # project.
7 #
8 # This program is free software; you can redistribute it and/or
9 # modify it under the terms of the GNU General Public License as
10 # published by the Free Software Foundation; either version 2 of
11 # the License, or (at your option) any later version.
12 #
13 # This program is distributed in the hope that it will be useful,
14 # but WITHOUT ANY WARRANTY; without even the implied warranty of
15 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 # GNU General Public License for more details.
17 #
18 # You should have received a copy of the GNU General Public License
19 # along with this program; if not, write to the Free Software
20 # Foundation, Inc., 59 Temple Place, Suite 330, Boston,
21 # MA 02111-1307 USA
22 #
24 Summary:
25 ========
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
31 code.
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.
46 Status:
47 =======
49 In general, all boards for which a configuration option exists in the
50 Makefile have been tested to some extent and can be considered
51 "working". In fact, many of them are used in production systems.
53 In case of problems see the CHANGELOG and CREDITS files to find out
54 who contributed the specific port. The MAINTAINERS file lists board
55 maintainers.
58 Where to get help:
59 ==================
61 In case you have questions about, problems with or contributions for
62 U-Boot you should send a message to the U-Boot mailing list at
63 <u-boot@lists.denx.de>. There is also an archive of previous traffic
64 on the mailing list - please search the archive before asking FAQ's.
65 Please see http://lists.denx.de/pipermail/u-boot and
66 http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
69 Where to get source code:
70 =========================
72 The U-Boot source code is maintained in the git repository at
73 git://www.denx.de/git/u-boot.git ; you can browse it online at
74 http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
76 The "snapshot" links on this page allow you to download tarballs of
77 any version you might be interested in. Official releases are also
78 available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
79 directory.
81 Pre-built (and tested) images are available from
82 ftp://ftp.denx.de/pub/u-boot/images/
85 Where we come from:
86 ===================
88 - start from 8xxrom sources
89 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
90 - clean up code
91 - make it easier to add custom boards
92 - make it possible to add other [PowerPC] CPUs
93 - extend functions, especially:
94 * Provide extended interface to Linux boot loader
95 * S-Record download
96 * network boot
97 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
98 - create ARMBoot project (http://sourceforge.net/projects/armboot)
99 - add other CPU families (starting with ARM)
100 - create U-Boot project (http://sourceforge.net/projects/u-boot)
101 - current project page: see http://www.denx.de/wiki/U-Boot
104 Names and Spelling:
105 ===================
107 The "official" name of this project is "Das U-Boot". The spelling
108 "U-Boot" shall be used in all written text (documentation, comments
109 in source files etc.). Example:
111 This is the README file for the U-Boot project.
113 File names etc. shall be based on the string "u-boot". Examples:
115 include/asm-ppc/u-boot.h
117 #include <asm/u-boot.h>
119 Variable names, preprocessor constants etc. shall be either based on
120 the string "u_boot" or on "U_BOOT". Example:
122 U_BOOT_VERSION u_boot_logo
123 IH_OS_U_BOOT u_boot_hush_start
126 Versioning:
127 ===========
129 Starting with the release in October 2008, the names of the releases
130 were changed from numerical release numbers without deeper meaning
131 into a time stamp based numbering. Regular releases are identified by
132 names consisting of the calendar year and month of the release date.
133 Additional fields (if present) indicate release candidates or bug fix
134 releases in "stable" maintenance trees.
136 Examples:
137 U-Boot v2009.11 - Release November 2009
138 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
139 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release
142 Directory Hierarchy:
143 ====================
145 /arch Architecture specific files
146 /arm Files generic to ARM architecture
147 /cpu CPU specific files
148 /arm720t Files specific to ARM 720 CPUs
149 /arm920t Files specific to ARM 920 CPUs
150 /at91 Files specific to Atmel AT91RM9200 CPU
151 /imx Files specific to Freescale MC9328 i.MX CPUs
152 /s3c24x0 Files specific to Samsung S3C24X0 CPUs
153 /arm925t Files specific to ARM 925 CPUs
154 /arm926ejs Files specific to ARM 926 CPUs
155 /arm1136 Files specific to ARM 1136 CPUs
156 /ixp Files specific to Intel XScale IXP CPUs
157 /pxa Files specific to Intel XScale PXA CPUs
158 /s3c44b0 Files specific to Samsung S3C44B0 CPUs
159 /sa1100 Files specific to Intel StrongARM SA1100 CPUs
160 /lib Architecture specific library files
161 /avr32 Files generic to AVR32 architecture
162 /cpu CPU specific files
163 /lib Architecture specific library files
164 /blackfin Files generic to Analog Devices Blackfin architecture
165 /cpu CPU specific files
166 /lib Architecture specific library files
167 /x86 Files generic to x86 architecture
168 /cpu CPU specific files
169 /lib Architecture specific library files
170 /m68k Files generic to m68k architecture
171 /cpu CPU specific files
172 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
173 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
174 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
175 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
176 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
177 /lib Architecture specific library files
178 /microblaze Files generic to microblaze architecture
179 /cpu CPU specific files
180 /lib Architecture specific library files
181 /mips Files generic to MIPS architecture
182 /cpu CPU specific files
183 /mips32 Files specific to MIPS32 CPUs
184 /xburst Files specific to Ingenic XBurst CPUs
185 /lib Architecture specific library files
186 /nds32 Files generic to NDS32 architecture
187 /cpu CPU specific files
188 /n1213 Files specific to Andes Technology N1213 CPUs
189 /lib Architecture specific library files
190 /nios2 Files generic to Altera NIOS2 architecture
191 /cpu CPU specific files
192 /lib Architecture specific library files
193 /powerpc Files generic to PowerPC architecture
194 /cpu CPU specific files
195 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
196 /mpc5xx Files specific to Freescale MPC5xx CPUs
197 /mpc5xxx Files specific to Freescale MPC5xxx CPUs
198 /mpc8xx Files specific to Freescale MPC8xx CPUs
199 /mpc8220 Files specific to Freescale MPC8220 CPUs
200 /mpc824x Files specific to Freescale MPC824x CPUs
201 /mpc8260 Files specific to Freescale MPC8260 CPUs
202 /mpc85xx Files specific to Freescale MPC85xx CPUs
203 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
204 /lib Architecture specific library files
205 /sh Files generic to SH architecture
206 /cpu CPU specific files
207 /sh2 Files specific to sh2 CPUs
208 /sh3 Files specific to sh3 CPUs
209 /sh4 Files specific to sh4 CPUs
210 /lib Architecture specific library files
211 /sparc Files generic to SPARC architecture
212 /cpu CPU specific files
213 /leon2 Files specific to Gaisler LEON2 SPARC CPU
214 /leon3 Files specific to Gaisler LEON3 SPARC CPU
215 /lib Architecture specific library files
216 /api Machine/arch independent API for external apps
217 /board Board dependent files
218 /common Misc architecture independent functions
219 /disk Code for disk drive partition handling
220 /doc Documentation (don't expect too much)
221 /drivers Commonly used device drivers
222 /examples Example code for standalone applications, etc.
223 /fs Filesystem code (cramfs, ext2, jffs2, etc.)
224 /include Header Files
225 /lib Files generic to all architectures
226 /libfdt Library files to support flattened device trees
227 /lzma Library files to support LZMA decompression
228 /lzo Library files to support LZO decompression
229 /net Networking code
230 /post Power On Self Test
231 /rtc Real Time Clock drivers
232 /tools Tools to build S-Record or U-Boot images, etc.
234 Software Configuration:
235 =======================
237 Configuration is usually done using C preprocessor defines; the
238 rationale behind that is to avoid dead code whenever possible.
240 There are two classes of configuration variables:
242 * Configuration _OPTIONS_:
243 These are selectable by the user and have names beginning with
244 "CONFIG_".
246 * Configuration _SETTINGS_:
247 These depend on the hardware etc. and should not be meddled with if
248 you don't know what you're doing; they have names beginning with
249 "CONFIG_SYS_".
251 Later we will add a configuration tool - probably similar to or even
252 identical to what's used for the Linux kernel. Right now, we have to
253 do the configuration by hand, which means creating some symbolic
254 links and editing some configuration files. We use the TQM8xxL boards
255 as an example here.
258 Selection of Processor Architecture and Board Type:
259 ---------------------------------------------------
261 For all supported boards there are ready-to-use default
262 configurations available; just type "make <board_name>_config".
264 Example: For a TQM823L module type:
266 cd u-boot
267 make TQM823L_config
269 For the Cogent platform, you need to specify the CPU type as well;
270 e.g. "make cogent_mpc8xx_config". And also configure the cogent
271 directory according to the instructions in cogent/README.
274 Configuration Options:
275 ----------------------
277 Configuration depends on the combination of board and CPU type; all
278 such information is kept in a configuration file
279 "include/configs/<board_name>.h".
281 Example: For a TQM823L module, all configuration settings are in
282 "include/configs/TQM823L.h".
285 Many of the options are named exactly as the corresponding Linux
286 kernel configuration options. The intention is to make it easier to
287 build a config tool - later.
290 The following options need to be configured:
292 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
294 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
296 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
297 Define exactly one, e.g. CONFIG_ATSTK1002
299 - CPU Module Type: (if CONFIG_COGENT is defined)
300 Define exactly one of
301 CONFIG_CMA286_60_OLD
302 --- FIXME --- not tested yet:
303 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
304 CONFIG_CMA287_23, CONFIG_CMA287_50
306 - Motherboard Type: (if CONFIG_COGENT is defined)
307 Define exactly one of
308 CONFIG_CMA101, CONFIG_CMA102
310 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
311 Define one or more of
312 CONFIG_CMA302
314 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
315 Define one or more of
316 CONFIG_LCD_HEARTBEAT - update a character position on
317 the LCD display every second with
318 a "rotator" |\-/|\-/
320 - Board flavour: (if CONFIG_MPC8260ADS is defined)
321 CONFIG_ADSTYPE
322 Possible values are:
323 CONFIG_SYS_8260ADS - original MPC8260ADS
324 CONFIG_SYS_8266ADS - MPC8266ADS
325 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
326 CONFIG_SYS_8272ADS - MPC8272ADS
328 - Marvell Family Member
329 CONFIG_SYS_MVFS - define it if you want to enable
330 multiple fs option at one time
331 for marvell soc family
333 - MPC824X Family Member (if CONFIG_MPC824X is defined)
334 Define exactly one of
335 CONFIG_MPC8240, CONFIG_MPC8245
337 - 8xx CPU Options: (if using an MPC8xx CPU)
338 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
339 get_gclk_freq() cannot work
340 e.g. if there is no 32KHz
341 reference PIT/RTC clock
342 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
343 or XTAL/EXTAL)
345 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
346 CONFIG_SYS_8xx_CPUCLK_MIN
347 CONFIG_SYS_8xx_CPUCLK_MAX
348 CONFIG_8xx_CPUCLK_DEFAULT
349 See doc/README.MPC866
351 CONFIG_SYS_MEASURE_CPUCLK
353 Define this to measure the actual CPU clock instead
354 of relying on the correctness of the configured
355 values. Mostly useful for board bringup to make sure
356 the PLL is locked at the intended frequency. Note
357 that this requires a (stable) reference clock (32 kHz
358 RTC clock or CONFIG_SYS_8XX_XIN)
360 CONFIG_SYS_DELAYED_ICACHE
362 Define this option if you want to enable the
363 ICache only when Code runs from RAM.
365 - 85xx CPU Options:
366 CONFIG_SYS_FSL_TBCLK_DIV
368 Defines the core time base clock divider ratio compared to the
369 system clock. On most PQ3 devices this is 8, on newer QorIQ
370 devices it can be 16 or 32. The ratio varies from SoC to Soc.
372 CONFIG_SYS_FSL_PCIE_COMPAT
374 Defines the string to utilize when trying to match PCIe device
375 tree nodes for the given platform.
377 - Intel Monahans options:
378 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
380 Defines the Monahans run mode to oscillator
381 ratio. Valid values are 8, 16, 24, 31. The core
382 frequency is this value multiplied by 13 MHz.
384 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
386 Defines the Monahans turbo mode to oscillator
387 ratio. Valid values are 1 (default if undefined) and
388 2. The core frequency as calculated above is multiplied
389 by this value.
391 - MIPS CPU options:
392 CONFIG_SYS_INIT_SP_OFFSET
394 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
395 pointer. This is needed for the temporary stack before
396 relocation.
398 CONFIG_SYS_MIPS_CACHE_MODE
400 Cache operation mode for the MIPS CPU.
401 See also arch/mips/include/asm/mipsregs.h.
402 Possible values are:
403 CONF_CM_CACHABLE_NO_WA
404 CONF_CM_CACHABLE_WA
405 CONF_CM_UNCACHED
406 CONF_CM_CACHABLE_NONCOHERENT
407 CONF_CM_CACHABLE_CE
408 CONF_CM_CACHABLE_COW
409 CONF_CM_CACHABLE_CUW
410 CONF_CM_CACHABLE_ACCELERATED
412 CONFIG_SYS_XWAY_EBU_BOOTCFG
414 Special option for Lantiq XWAY SoCs for booting from NOR flash.
415 See also arch/mips/cpu/mips32/start.S.
417 CONFIG_XWAY_SWAP_BYTES
419 Enable compilation of tools/xway-swap-bytes needed for Lantiq
420 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
421 be swapped if a flash programmer is used.
423 - ARM options:
424 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
426 Select high exception vectors of the ARM core, e.g., do not
427 clear the V bit of the c1 register of CP15.
429 - Linux Kernel Interface:
430 CONFIG_CLOCKS_IN_MHZ
432 U-Boot stores all clock information in Hz
433 internally. For binary compatibility with older Linux
434 kernels (which expect the clocks passed in the
435 bd_info data to be in MHz) the environment variable
436 "clocks_in_mhz" can be defined so that U-Boot
437 converts clock data to MHZ before passing it to the
438 Linux kernel.
439 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
440 "clocks_in_mhz=1" is automatically included in the
441 default environment.
443 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
445 When transferring memsize parameter to linux, some versions
446 expect it to be in bytes, others in MB.
447 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
449 CONFIG_OF_LIBFDT
451 New kernel versions are expecting firmware settings to be
452 passed using flattened device trees (based on open firmware
453 concepts).
455 CONFIG_OF_LIBFDT
456 * New libfdt-based support
457 * Adds the "fdt" command
458 * The bootm command automatically updates the fdt
460 OF_CPU - The proper name of the cpus node (only required for
461 MPC512X and MPC5xxx based boards).
462 OF_SOC - The proper name of the soc node (only required for
463 MPC512X and MPC5xxx based boards).
464 OF_TBCLK - The timebase frequency.
465 OF_STDOUT_PATH - The path to the console device
467 boards with QUICC Engines require OF_QE to set UCC MAC
468 addresses
470 CONFIG_OF_BOARD_SETUP
472 Board code has addition modification that it wants to make
473 to the flat device tree before handing it off to the kernel
475 CONFIG_OF_BOOT_CPU
477 This define fills in the correct boot CPU in the boot
478 param header, the default value is zero if undefined.
480 CONFIG_OF_IDE_FIXUP
482 U-Boot can detect if an IDE device is present or not.
483 If not, and this new config option is activated, U-Boot
484 removes the ATA node from the DTS before booting Linux,
485 so the Linux IDE driver does not probe the device and
486 crash. This is needed for buggy hardware (uc101) where
487 no pull down resistor is connected to the signal IDE5V_DD7.
489 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
491 This setting is mandatory for all boards that have only one
492 machine type and must be used to specify the machine type
493 number as it appears in the ARM machine registry
494 (see http://www.arm.linux.org.uk/developer/machines/).
495 Only boards that have multiple machine types supported
496 in a single configuration file and the machine type is
497 runtime discoverable, do not have to use this setting.
499 - vxWorks boot parameters:
501 bootvx constructs a valid bootline using the following
502 environments variables: bootfile, ipaddr, serverip, hostname.
503 It loads the vxWorks image pointed bootfile.
505 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
506 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
507 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
508 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
510 CONFIG_SYS_VXWORKS_ADD_PARAMS
512 Add it at the end of the bootline. E.g "u=username pw=secret"
514 Note: If a "bootargs" environment is defined, it will overwride
515 the defaults discussed just above.
517 - Cache Configuration:
518 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
519 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
520 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
522 - Cache Configuration for ARM:
523 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
524 controller
525 CONFIG_SYS_PL310_BASE - Physical base address of PL310
526 controller register space
528 - Serial Ports:
529 CONFIG_PL010_SERIAL
531 Define this if you want support for Amba PrimeCell PL010 UARTs.
533 CONFIG_PL011_SERIAL
535 Define this if you want support for Amba PrimeCell PL011 UARTs.
537 CONFIG_PL011_CLOCK
539 If you have Amba PrimeCell PL011 UARTs, set this variable to
540 the clock speed of the UARTs.
542 CONFIG_PL01x_PORTS
544 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
545 define this to a list of base addresses for each (supported)
546 port. See e.g. include/configs/versatile.h
548 CONFIG_PL011_SERIAL_RLCR
550 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
551 have separate receive and transmit line control registers. Set
552 this variable to initialize the extra register.
554 CONFIG_PL011_SERIAL_FLUSH_ON_INIT
556 On some platforms (e.g. U8500) U-Boot is loaded by a second stage
557 boot loader that has already initialized the UART. Define this
558 variable to flush the UART at init time.
561 - Console Interface:
562 Depending on board, define exactly one serial port
563 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
564 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
565 console by defining CONFIG_8xx_CONS_NONE
567 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
568 port routines must be defined elsewhere
569 (i.e. serial_init(), serial_getc(), ...)
571 CONFIG_CFB_CONSOLE
572 Enables console device for a color framebuffer. Needs following
573 defines (cf. smiLynxEM, i8042)
574 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
575 (default big endian)
576 VIDEO_HW_RECTFILL graphic chip supports
577 rectangle fill
578 (cf. smiLynxEM)
579 VIDEO_HW_BITBLT graphic chip supports
580 bit-blit (cf. smiLynxEM)
581 VIDEO_VISIBLE_COLS visible pixel columns
582 (cols=pitch)
583 VIDEO_VISIBLE_ROWS visible pixel rows
584 VIDEO_PIXEL_SIZE bytes per pixel
585 VIDEO_DATA_FORMAT graphic data format
586 (0-5, cf. cfb_console.c)
587 VIDEO_FB_ADRS framebuffer address
588 VIDEO_KBD_INIT_FCT keyboard int fct
589 (i.e. i8042_kbd_init())
590 VIDEO_TSTC_FCT test char fct
591 (i.e. i8042_tstc)
592 VIDEO_GETC_FCT get char fct
593 (i.e. i8042_getc)
594 CONFIG_CONSOLE_CURSOR cursor drawing on/off
595 (requires blink timer
596 cf. i8042.c)
597 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
598 CONFIG_CONSOLE_TIME display time/date info in
599 upper right corner
600 (requires CONFIG_CMD_DATE)
601 CONFIG_VIDEO_LOGO display Linux logo in
602 upper left corner
603 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
604 linux_logo.h for logo.
605 Requires CONFIG_VIDEO_LOGO
606 CONFIG_CONSOLE_EXTRA_INFO
607 additional board info beside
608 the logo
610 When CONFIG_CFB_CONSOLE is defined, video console is
611 default i/o. Serial console can be forced with
612 environment 'console=serial'.
614 When CONFIG_SILENT_CONSOLE is defined, all console
615 messages (by U-Boot and Linux!) can be silenced with
616 the "silent" environment variable. See
617 doc/README.silent for more information.
619 - Console Baudrate:
620 CONFIG_BAUDRATE - in bps
621 Select one of the baudrates listed in
622 CONFIG_SYS_BAUDRATE_TABLE, see below.
623 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
625 - Console Rx buffer length
626 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
627 the maximum receive buffer length for the SMC.
628 This option is actual only for 82xx and 8xx possible.
629 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
630 must be defined, to setup the maximum idle timeout for
631 the SMC.
633 - Pre-Console Buffer:
634 Prior to the console being initialised (i.e. serial UART
635 initialised etc) all console output is silently discarded.
636 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to
637 buffer any console messages prior to the console being
638 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ
639 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is
640 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ
641 bytes are output before the console is initialised, the
642 earlier bytes are discarded.
644 'Sane' compilers will generate smaller code if
645 CONFIG_PRE_CON_BUF_SZ is a power of 2
647 - Pre-console putc():
648 Prior to the console being initialised, console output is
649 normally silently discarded. This can be annoying if a
650 panic() happens in this time.
652 If the CONFIG_PRE_CONSOLE_PUTC option is defined, then
653 U-Boot will call board_pre_console_putc() for each output
654 character in this case, This function should try to output
655 the character if possible, perhaps on all available UARTs
656 (it will need to do this directly, since the console code
657 is not functional yet). Note that if the panic happens
658 early enough, then it is possible that board_init_f()
659 (or even arch_cpu_init() on ARM) has not been called yet.
660 You should init all clocks, GPIOs, etc. that are needed
661 to get the character out. Baud rates will need to default
662 to something sensible.
664 - Safe printf() functions
665 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of
666 the printf() functions. These are defined in
667 include/vsprintf.h and include snprintf(), vsnprintf() and
668 so on. Code size increase is approximately 300-500 bytes.
669 If this option is not given then these functions will
670 silently discard their buffer size argument - this means
671 you are not getting any overflow checking in this case.
673 - Boot Delay: CONFIG_BOOTDELAY - in seconds
674 Delay before automatically booting the default image;
675 set to -1 to disable autoboot.
677 See doc/README.autoboot for these options that
678 work with CONFIG_BOOTDELAY. None are required.
679 CONFIG_BOOT_RETRY_TIME
680 CONFIG_BOOT_RETRY_MIN
681 CONFIG_AUTOBOOT_KEYED
682 CONFIG_AUTOBOOT_PROMPT
683 CONFIG_AUTOBOOT_DELAY_STR
684 CONFIG_AUTOBOOT_STOP_STR
685 CONFIG_AUTOBOOT_DELAY_STR2
686 CONFIG_AUTOBOOT_STOP_STR2
687 CONFIG_ZERO_BOOTDELAY_CHECK
688 CONFIG_RESET_TO_RETRY
690 - Autoboot Command:
691 CONFIG_BOOTCOMMAND
692 Only needed when CONFIG_BOOTDELAY is enabled;
693 define a command string that is automatically executed
694 when no character is read on the console interface
695 within "Boot Delay" after reset.
697 CONFIG_BOOTARGS
698 This can be used to pass arguments to the bootm
699 command. The value of CONFIG_BOOTARGS goes into the
700 environment value "bootargs".
702 CONFIG_RAMBOOT and CONFIG_NFSBOOT
703 The value of these goes into the environment as
704 "ramboot" and "nfsboot" respectively, and can be used
705 as a convenience, when switching between booting from
706 RAM and NFS.
708 - Pre-Boot Commands:
709 CONFIG_PREBOOT
711 When this option is #defined, the existence of the
712 environment variable "preboot" will be checked
713 immediately before starting the CONFIG_BOOTDELAY
714 countdown and/or running the auto-boot command resp.
715 entering interactive mode.
717 This feature is especially useful when "preboot" is
718 automatically generated or modified. For an example
719 see the LWMON board specific code: here "preboot" is
720 modified when the user holds down a certain
721 combination of keys on the (special) keyboard when
722 booting the systems
724 - Serial Download Echo Mode:
725 CONFIG_LOADS_ECHO
726 If defined to 1, all characters received during a
727 serial download (using the "loads" command) are
728 echoed back. This might be needed by some terminal
729 emulations (like "cu"), but may as well just take
730 time on others. This setting #define's the initial
731 value of the "loads_echo" environment variable.
733 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
734 CONFIG_KGDB_BAUDRATE
735 Select one of the baudrates listed in
736 CONFIG_SYS_BAUDRATE_TABLE, see below.
738 - Monitor Functions:
739 Monitor commands can be included or excluded
740 from the build by using the #include files
741 "config_cmd_all.h" and #undef'ing unwanted
742 commands, or using "config_cmd_default.h"
743 and augmenting with additional #define's
744 for wanted commands.
746 The default command configuration includes all commands
747 except those marked below with a "*".
749 CONFIG_CMD_ASKENV * ask for env variable
750 CONFIG_CMD_BDI bdinfo
751 CONFIG_CMD_BEDBUG * Include BedBug Debugger
752 CONFIG_CMD_BMP * BMP support
753 CONFIG_CMD_BSP * Board specific commands
754 CONFIG_CMD_BOOTD bootd
755 CONFIG_CMD_CACHE * icache, dcache
756 CONFIG_CMD_CONSOLE coninfo
757 CONFIG_CMD_CRC32 * crc32
758 CONFIG_CMD_DATE * support for RTC, date/time...
759 CONFIG_CMD_DHCP * DHCP support
760 CONFIG_CMD_DIAG * Diagnostics
761 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
762 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
763 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
764 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
765 CONFIG_CMD_DTT * Digital Therm and Thermostat
766 CONFIG_CMD_ECHO echo arguments
767 CONFIG_CMD_EDITENV edit env variable
768 CONFIG_CMD_EEPROM * EEPROM read/write support
769 CONFIG_CMD_ELF * bootelf, bootvx
770 CONFIG_CMD_EXPORTENV * export the environment
771 CONFIG_CMD_SAVEENV saveenv
772 CONFIG_CMD_FDC * Floppy Disk Support
773 CONFIG_CMD_FAT * FAT partition support
774 CONFIG_CMD_FDOS * Dos diskette Support
775 CONFIG_CMD_FLASH flinfo, erase, protect
776 CONFIG_CMD_FPGA FPGA device initialization support
777 CONFIG_CMD_GO * the 'go' command (exec code)
778 CONFIG_CMD_GREPENV * search environment
779 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
780 CONFIG_CMD_I2C * I2C serial bus support
781 CONFIG_CMD_IDE * IDE harddisk support
782 CONFIG_CMD_IMI iminfo
783 CONFIG_CMD_IMLS List all found images
784 CONFIG_CMD_IMMAP * IMMR dump support
785 CONFIG_CMD_IMPORTENV * import an environment
786 CONFIG_CMD_IRQ * irqinfo
787 CONFIG_CMD_ITEST Integer/string test of 2 values
788 CONFIG_CMD_JFFS2 * JFFS2 Support
789 CONFIG_CMD_KGDB * kgdb
790 CONFIG_CMD_LDRINFO ldrinfo (display Blackfin loader)
791 CONFIG_CMD_LOADB loadb
792 CONFIG_CMD_LOADS loads
793 CONFIG_CMD_MD5SUM print md5 message digest
794 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
795 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
796 loop, loopw, mtest
797 CONFIG_CMD_MISC Misc functions like sleep etc
798 CONFIG_CMD_MMC * MMC memory mapped support
799 CONFIG_CMD_MII * MII utility commands
800 CONFIG_CMD_MTDPARTS * MTD partition support
801 CONFIG_CMD_NAND * NAND support
802 CONFIG_CMD_NET bootp, tftpboot, rarpboot
803 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
804 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
805 CONFIG_CMD_PCI * pciinfo
806 CONFIG_CMD_PCMCIA * PCMCIA support
807 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
808 host
809 CONFIG_CMD_PORTIO * Port I/O
810 CONFIG_CMD_REGINFO * Register dump
811 CONFIG_CMD_RUN run command in env variable
812 CONFIG_CMD_SAVES * save S record dump
813 CONFIG_CMD_SCSI * SCSI Support
814 CONFIG_CMD_SDRAM * print SDRAM configuration information
815 (requires CONFIG_CMD_I2C)
816 CONFIG_CMD_SETGETDCR Support for DCR Register access
817 (4xx only)
818 CONFIG_CMD_SF * Read/write/erase SPI NOR flash
819 CONFIG_CMD_SHA1SUM print sha1 memory digest
820 (requires CONFIG_CMD_MEMORY)
821 CONFIG_CMD_SOURCE "source" command Support
822 CONFIG_CMD_SPI * SPI serial bus support
823 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
824 CONFIG_CMD_TFTPPUT * TFTP put command (upload)
825 CONFIG_CMD_TIME * run command and report execution time
826 CONFIG_CMD_USB * USB support
827 CONFIG_CMD_CDP * Cisco Discover Protocol support
828 CONFIG_CMD_FSL * Microblaze FSL support
831 EXAMPLE: If you want all functions except of network
832 support you can write:
834 #include "config_cmd_all.h"
835 #undef CONFIG_CMD_NET
837 Other Commands:
838 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
840 Note: Don't enable the "icache" and "dcache" commands
841 (configuration option CONFIG_CMD_CACHE) unless you know
842 what you (and your U-Boot users) are doing. Data
843 cache cannot be enabled on systems like the 8xx or
844 8260 (where accesses to the IMMR region must be
845 uncached), and it cannot be disabled on all other
846 systems where we (mis-) use the data cache to hold an
847 initial stack and some data.
850 XXX - this list needs to get updated!
852 - Device tree:
853 CONFIG_OF_CONTROL
854 If this variable is defined, U-Boot will use a device tree
855 to configure its devices, instead of relying on statically
856 compiled #defines in the board file. This option is
857 experimental and only available on a few boards. The device
858 tree is available in the global data as gd->fdt_blob.
860 U-Boot needs to get its device tree from somewhere. This can
861 be done using one of the two options below:
863 CONFIG_OF_EMBED
864 If this variable is defined, U-Boot will embed a device tree
865 binary in its image. This device tree file should be in the
866 board directory and called <soc>-<board>.dts. The binary file
867 is then picked up in board_init_f() and made available through
868 the global data structure as gd->blob.
870 CONFIG_OF_SEPARATE
871 If this variable is defined, U-Boot will build a device tree
872 binary. It will be called u-boot.dtb. Architecture-specific
873 code will locate it at run-time. Generally this works by:
875 cat u-boot.bin u-boot.dtb >image.bin
877 and in fact, U-Boot does this for you, creating a file called
878 u-boot-dtb.bin which is useful in the common case. You can
879 still use the individual files if you need something more
880 exotic.
882 - Watchdog:
883 CONFIG_WATCHDOG
884 If this variable is defined, it enables watchdog
885 support for the SoC. There must be support in the SoC
886 specific code for a watchdog. For the 8xx and 8260
887 CPUs, the SIU Watchdog feature is enabled in the SYPCR
888 register. When supported for a specific SoC is
889 available, then no further board specific code should
890 be needed to use it.
892 CONFIG_HW_WATCHDOG
893 When using a watchdog circuitry external to the used
894 SoC, then define this variable and provide board
895 specific code for the "hw_watchdog_reset" function.
897 - U-Boot Version:
898 CONFIG_VERSION_VARIABLE
899 If this variable is defined, an environment variable
900 named "ver" is created by U-Boot showing the U-Boot
901 version as printed by the "version" command.
902 This variable is readonly.
904 - Real-Time Clock:
906 When CONFIG_CMD_DATE is selected, the type of the RTC
907 has to be selected, too. Define exactly one of the
908 following options:
910 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
911 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
912 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
913 CONFIG_RTC_MC146818 - use MC146818 RTC
914 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
915 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
916 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
917 CONFIG_RTC_DS164x - use Dallas DS164x RTC
918 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
919 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
920 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
921 CONFIG_SYS_RV3029_TCR - enable trickle charger on
922 RV3029 RTC.
924 Note that if the RTC uses I2C, then the I2C interface
925 must also be configured. See I2C Support, below.
927 - GPIO Support:
928 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
929 CONFIG_PCA953X_INFO - enable pca953x info command
931 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
932 chip-ngpio pairs that tell the PCA953X driver the number of
933 pins supported by a particular chip.
935 Note that if the GPIO device uses I2C, then the I2C interface
936 must also be configured. See I2C Support, below.
938 - Timestamp Support:
940 When CONFIG_TIMESTAMP is selected, the timestamp
941 (date and time) of an image is printed by image
942 commands like bootm or iminfo. This option is
943 automatically enabled when you select CONFIG_CMD_DATE .
945 - Partition Support:
946 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
947 and/or CONFIG_ISO_PARTITION and/or CONFIG_EFI_PARTITION
949 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
950 CONFIG_CMD_SCSI) you must configure support for at
951 least one partition type as well.
953 - IDE Reset method:
954 CONFIG_IDE_RESET_ROUTINE - this is defined in several
955 board configurations files but used nowhere!
957 CONFIG_IDE_RESET - is this is defined, IDE Reset will
958 be performed by calling the function
959 ide_set_reset(int reset)
960 which has to be defined in a board specific file
962 - ATAPI Support:
963 CONFIG_ATAPI
965 Set this to enable ATAPI support.
967 - LBA48 Support
968 CONFIG_LBA48
970 Set this to enable support for disks larger than 137GB
971 Also look at CONFIG_SYS_64BIT_LBA.
972 Whithout these , LBA48 support uses 32bit variables and will 'only'
973 support disks up to 2.1TB.
975 CONFIG_SYS_64BIT_LBA:
976 When enabled, makes the IDE subsystem use 64bit sector addresses.
977 Default is 32bit.
979 - SCSI Support:
980 At the moment only there is only support for the
981 SYM53C8XX SCSI controller; define
982 CONFIG_SCSI_SYM53C8XX to enable it.
984 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
985 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
986 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
987 maximum numbers of LUNs, SCSI ID's and target
988 devices.
989 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
991 - NETWORK Support (PCI):
992 CONFIG_E1000
993 Support for Intel 8254x/8257x gigabit chips.
995 CONFIG_E1000_SPI
996 Utility code for direct access to the SPI bus on Intel 8257x.
997 This does not do anything useful unless you set at least one
998 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
1000 CONFIG_E1000_SPI_GENERIC
1001 Allow generic access to the SPI bus on the Intel 8257x, for
1002 example with the "sspi" command.
1004 CONFIG_CMD_E1000
1005 Management command for E1000 devices. When used on devices
1006 with SPI support you can reprogram the EEPROM from U-Boot.
1008 CONFIG_E1000_FALLBACK_MAC
1009 default MAC for empty EEPROM after production.
1011 CONFIG_EEPRO100
1012 Support for Intel 82557/82559/82559ER chips.
1013 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
1014 write routine for first time initialisation.
1016 CONFIG_TULIP
1017 Support for Digital 2114x chips.
1018 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
1019 modem chip initialisation (KS8761/QS6611).
1021 CONFIG_NATSEMI
1022 Support for National dp83815 chips.
1024 CONFIG_NS8382X
1025 Support for National dp8382[01] gigabit chips.
1027 - NETWORK Support (other):
1029 CONFIG_DRIVER_AT91EMAC
1030 Support for AT91RM9200 EMAC.
1032 CONFIG_RMII
1033 Define this to use reduced MII inteface
1035 CONFIG_DRIVER_AT91EMAC_QUIET
1036 If this defined, the driver is quiet.
1037 The driver doen't show link status messages.
1039 CONFIG_CALXEDA_XGMAC
1040 Support for the Calxeda XGMAC device
1042 CONFIG_DRIVER_LAN91C96
1043 Support for SMSC's LAN91C96 chips.
1045 CONFIG_LAN91C96_BASE
1046 Define this to hold the physical address
1047 of the LAN91C96's I/O space
1049 CONFIG_LAN91C96_USE_32_BIT
1050 Define this to enable 32 bit addressing
1052 CONFIG_DRIVER_SMC91111
1053 Support for SMSC's LAN91C111 chip
1055 CONFIG_SMC91111_BASE
1056 Define this to hold the physical address
1057 of the device (I/O space)
1059 CONFIG_SMC_USE_32_BIT
1060 Define this if data bus is 32 bits
1062 CONFIG_SMC_USE_IOFUNCS
1063 Define this to use i/o functions instead of macros
1064 (some hardware wont work with macros)
1066 CONFIG_DRIVER_TI_EMAC
1067 Support for davinci emac
1069 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
1070 Define this if you have more then 3 PHYs.
1072 CONFIG_FTGMAC100
1073 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
1075 CONFIG_FTGMAC100_EGIGA
1076 Define this to use GE link update with gigabit PHY.
1077 Define this if FTGMAC100 is connected to gigabit PHY.
1078 If your system has 10/100 PHY only, it might not occur
1079 wrong behavior. Because PHY usually return timeout or
1080 useless data when polling gigabit status and gigabit
1081 control registers. This behavior won't affect the
1082 correctnessof 10/100 link speed update.
1084 CONFIG_SMC911X
1085 Support for SMSC's LAN911x and LAN921x chips
1087 CONFIG_SMC911X_BASE
1088 Define this to hold the physical address
1089 of the device (I/O space)
1091 CONFIG_SMC911X_32_BIT
1092 Define this if data bus is 32 bits
1094 CONFIG_SMC911X_16_BIT
1095 Define this if data bus is 16 bits. If your processor
1096 automatically converts one 32 bit word to two 16 bit
1097 words you may also try CONFIG_SMC911X_32_BIT.
1099 CONFIG_SH_ETHER
1100 Support for Renesas on-chip Ethernet controller
1102 CONFIG_SH_ETHER_USE_PORT
1103 Define the number of ports to be used
1105 CONFIG_SH_ETHER_PHY_ADDR
1106 Define the ETH PHY's address
1108 CONFIG_SH_ETHER_CACHE_WRITEBACK
1109 If this option is set, the driver enables cache flush.
1111 - TPM Support:
1112 CONFIG_GENERIC_LPC_TPM
1113 Support for generic parallel port TPM devices. Only one device
1114 per system is supported at this time.
1116 CONFIG_TPM_TIS_BASE_ADDRESS
1117 Base address where the generic TPM device is mapped
1118 to. Contemporary x86 systems usually map it at
1119 0xfed40000.
1121 - USB Support:
1122 At the moment only the UHCI host controller is
1123 supported (PIP405, MIP405, MPC5200); define
1124 CONFIG_USB_UHCI to enable it.
1125 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
1126 and define CONFIG_USB_STORAGE to enable the USB
1127 storage devices.
1128 Note:
1129 Supported are USB Keyboards and USB Floppy drives
1130 (TEAC FD-05PUB).
1131 MPC5200 USB requires additional defines:
1132 CONFIG_USB_CLOCK
1133 for 528 MHz Clock: 0x0001bbbb
1134 CONFIG_PSC3_USB
1135 for USB on PSC3
1136 CONFIG_USB_CONFIG
1137 for differential drivers: 0x00001000
1138 for single ended drivers: 0x00005000
1139 for differential drivers on PSC3: 0x00000100
1140 for single ended drivers on PSC3: 0x00004100
1141 CONFIG_SYS_USB_EVENT_POLL
1142 May be defined to allow interrupt polling
1143 instead of using asynchronous interrupts
1145 - USB Device:
1146 Define the below if you wish to use the USB console.
1147 Once firmware is rebuilt from a serial console issue the
1148 command "setenv stdin usbtty; setenv stdout usbtty" and
1149 attach your USB cable. The Unix command "dmesg" should print
1150 it has found a new device. The environment variable usbtty
1151 can be set to gserial or cdc_acm to enable your device to
1152 appear to a USB host as a Linux gserial device or a
1153 Common Device Class Abstract Control Model serial device.
1154 If you select usbtty = gserial you should be able to enumerate
1155 a Linux host by
1156 # modprobe usbserial vendor=0xVendorID product=0xProductID
1157 else if using cdc_acm, simply setting the environment
1158 variable usbtty to be cdc_acm should suffice. The following
1159 might be defined in YourBoardName.h
1161 CONFIG_USB_DEVICE
1162 Define this to build a UDC device
1164 CONFIG_USB_TTY
1165 Define this to have a tty type of device available to
1166 talk to the UDC device
1168 CONFIG_SYS_CONSOLE_IS_IN_ENV
1169 Define this if you want stdin, stdout &/or stderr to
1170 be set to usbtty.
1172 mpc8xx:
1173 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
1174 Derive USB clock from external clock "blah"
1175 - CONFIG_SYS_USB_EXTC_CLK 0x02
1177 CONFIG_SYS_USB_BRG_CLK 0xBLAH
1178 Derive USB clock from brgclk
1179 - CONFIG_SYS_USB_BRG_CLK 0x04
1181 If you have a USB-IF assigned VendorID then you may wish to
1182 define your own vendor specific values either in BoardName.h
1183 or directly in usbd_vendor_info.h. If you don't define
1184 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1185 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1186 should pretend to be a Linux device to it's target host.
1188 CONFIG_USBD_MANUFACTURER
1189 Define this string as the name of your company for
1190 - CONFIG_USBD_MANUFACTURER "my company"
1192 CONFIG_USBD_PRODUCT_NAME
1193 Define this string as the name of your product
1194 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1196 CONFIG_USBD_VENDORID
1197 Define this as your assigned Vendor ID from the USB
1198 Implementors Forum. This *must* be a genuine Vendor ID
1199 to avoid polluting the USB namespace.
1200 - CONFIG_USBD_VENDORID 0xFFFF
1202 CONFIG_USBD_PRODUCTID
1203 Define this as the unique Product ID
1204 for your device
1205 - CONFIG_USBD_PRODUCTID 0xFFFF
1207 - ULPI Layer Support:
1208 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1209 the generic ULPI layer. The generic layer accesses the ULPI PHY
1210 via the platform viewport, so you need both the genric layer and
1211 the viewport enabled. Currently only Chipidea/ARC based
1212 viewport is supported.
1213 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1214 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
1216 - MMC Support:
1217 The MMC controller on the Intel PXA is supported. To
1218 enable this define CONFIG_MMC. The MMC can be
1219 accessed from the boot prompt by mapping the device
1220 to physical memory similar to flash. Command line is
1221 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1222 the FAT fs. This is enabled with CONFIG_CMD_FAT.
1224 CONFIG_SH_MMCIF
1225 Support for Renesas on-chip MMCIF controller
1227 CONFIG_SH_MMCIF_ADDR
1228 Define the base address of MMCIF registers
1230 CONFIG_SH_MMCIF_CLK
1231 Define the clock frequency for MMCIF
1233 - Journaling Flash filesystem support:
1234 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1235 CONFIG_JFFS2_NAND_DEV
1236 Define these for a default partition on a NAND device
1238 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1239 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1240 Define these for a default partition on a NOR device
1242 CONFIG_SYS_JFFS_CUSTOM_PART
1243 Define this to create an own partition. You have to provide a
1244 function struct part_info* jffs2_part_info(int part_num)
1246 If you define only one JFFS2 partition you may also want to
1247 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1248 to disable the command chpart. This is the default when you
1249 have not defined a custom partition
1251 - FAT(File Allocation Table) filesystem write function support:
1252 CONFIG_FAT_WRITE
1253 Support for saving memory data as a file
1254 in FAT formatted partition
1256 - Keyboard Support:
1257 CONFIG_ISA_KEYBOARD
1259 Define this to enable standard (PC-Style) keyboard
1260 support
1262 CONFIG_I8042_KBD
1263 Standard PC keyboard driver with US (is default) and
1264 GERMAN key layout (switch via environment 'keymap=de') support.
1265 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1266 for cfb_console. Supports cursor blinking.
1268 - Video support:
1269 CONFIG_VIDEO
1271 Define this to enable video support (for output to
1272 video).
1274 CONFIG_VIDEO_CT69000
1276 Enable Chips & Technologies 69000 Video chip
1278 CONFIG_VIDEO_SMI_LYNXEM
1279 Enable Silicon Motion SMI 712/710/810 Video chip. The
1280 video output is selected via environment 'videoout'
1281 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1282 assumed.
1284 For the CT69000 and SMI_LYNXEM drivers, videomode is
1285 selected via environment 'videomode'. Two different ways
1286 are possible:
1287 - "videomode=num" 'num' is a standard LiLo mode numbers.
1288 Following standard modes are supported (* is default):
1290 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1291 -------------+---------------------------------------------
1292 8 bits | 0x301* 0x303 0x305 0x161 0x307
1293 15 bits | 0x310 0x313 0x316 0x162 0x319
1294 16 bits | 0x311 0x314 0x317 0x163 0x31A
1295 24 bits | 0x312 0x315 0x318 ? 0x31B
1296 -------------+---------------------------------------------
1297 (i.e. setenv videomode 317; saveenv; reset;)
1299 - "videomode=bootargs" all the video parameters are parsed
1300 from the bootargs. (See drivers/video/videomodes.c)
1303 CONFIG_VIDEO_SED13806
1304 Enable Epson SED13806 driver. This driver supports 8bpp
1305 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1306 or CONFIG_VIDEO_SED13806_16BPP
1308 CONFIG_FSL_DIU_FB
1309 Enable the Freescale DIU video driver. Reference boards for
1310 SOCs that have a DIU should define this macro to enable DIU
1311 support, and should also define these other macros:
1313 CONFIG_SYS_DIU_ADDR
1314 CONFIG_VIDEO
1315 CONFIG_CMD_BMP
1316 CONFIG_CFB_CONSOLE
1317 CONFIG_VIDEO_SW_CURSOR
1318 CONFIG_VGA_AS_SINGLE_DEVICE
1319 CONFIG_VIDEO_LOGO
1320 CONFIG_VIDEO_BMP_LOGO
1322 The DIU driver will look for the 'video-mode' environment
1323 variable, and if defined, enable the DIU as a console during
1324 boot. See the documentation file README.video for a
1325 description of this variable.
1327 - Keyboard Support:
1328 CONFIG_KEYBOARD
1330 Define this to enable a custom keyboard support.
1331 This simply calls drv_keyboard_init() which must be
1332 defined in your board-specific files.
1333 The only board using this so far is RBC823.
1335 - LCD Support: CONFIG_LCD
1337 Define this to enable LCD support (for output to LCD
1338 display); also select one of the supported displays
1339 by defining one of these:
1341 CONFIG_ATMEL_LCD:
1343 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1345 CONFIG_NEC_NL6448AC33:
1347 NEC NL6448AC33-18. Active, color, single scan.
1349 CONFIG_NEC_NL6448BC20
1351 NEC NL6448BC20-08. 6.5", 640x480.
1352 Active, color, single scan.
1354 CONFIG_NEC_NL6448BC33_54
1356 NEC NL6448BC33-54. 10.4", 640x480.
1357 Active, color, single scan.
1359 CONFIG_SHARP_16x9
1361 Sharp 320x240. Active, color, single scan.
1362 It isn't 16x9, and I am not sure what it is.
1364 CONFIG_SHARP_LQ64D341
1366 Sharp LQ64D341 display, 640x480.
1367 Active, color, single scan.
1369 CONFIG_HLD1045
1371 HLD1045 display, 640x480.
1372 Active, color, single scan.
1374 CONFIG_OPTREX_BW
1376 Optrex CBL50840-2 NF-FW 99 22 M5
1377 or
1378 Hitachi LMG6912RPFC-00T
1379 or
1380 Hitachi SP14Q002
1382 320x240. Black & white.
1384 Normally display is black on white background; define
1385 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1387 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1389 If this option is set, the environment is checked for
1390 a variable "splashimage". If found, the usual display
1391 of logo, copyright and system information on the LCD
1392 is suppressed and the BMP image at the address
1393 specified in "splashimage" is loaded instead. The
1394 console is redirected to the "nulldev", too. This
1395 allows for a "silent" boot where a splash screen is
1396 loaded very quickly after power-on.
1398 CONFIG_SPLASH_SCREEN_ALIGN
1400 If this option is set the splash image can be freely positioned
1401 on the screen. Environment variable "splashpos" specifies the
1402 position as "x,y". If a positive number is given it is used as
1403 number of pixel from left/top. If a negative number is given it
1404 is used as number of pixel from right/bottom. You can also
1405 specify 'm' for centering the image.
1407 Example:
1408 setenv splashpos m,m
1409 => image at center of screen
1411 setenv splashpos 30,20
1412 => image at x = 30 and y = 20
1414 setenv splashpos -10,m
1415 => vertically centered image
1416 at x = dspWidth - bmpWidth - 9
1418 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1420 If this option is set, additionally to standard BMP
1421 images, gzipped BMP images can be displayed via the
1422 splashscreen support or the bmp command.
1424 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1426 If this option is set, 8-bit RLE compressed BMP images
1427 can be displayed via the splashscreen support or the
1428 bmp command.
1430 - Compression support:
1431 CONFIG_BZIP2
1433 If this option is set, support for bzip2 compressed
1434 images is included. If not, only uncompressed and gzip
1435 compressed images are supported.
1437 NOTE: the bzip2 algorithm requires a lot of RAM, so
1438 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1439 be at least 4MB.
1441 CONFIG_LZMA
1443 If this option is set, support for lzma compressed
1444 images is included.
1446 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1447 requires an amount of dynamic memory that is given by the
1448 formula:
1450 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1452 Where lc and lp stand for, respectively, Literal context bits
1453 and Literal pos bits.
1455 This value is upper-bounded by 14MB in the worst case. Anyway,
1456 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1457 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1458 a very small buffer.
1460 Use the lzmainfo tool to determinate the lc and lp values and
1461 then calculate the amount of needed dynamic memory (ensuring
1462 the appropriate CONFIG_SYS_MALLOC_LEN value).
1464 - MII/PHY support:
1465 CONFIG_PHY_ADDR
1467 The address of PHY on MII bus.
1469 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1471 The clock frequency of the MII bus
1473 CONFIG_PHY_GIGE
1475 If this option is set, support for speed/duplex
1476 detection of gigabit PHY is included.
1478 CONFIG_PHY_RESET_DELAY
1480 Some PHY like Intel LXT971A need extra delay after
1481 reset before any MII register access is possible.
1482 For such PHY, set this option to the usec delay
1483 required. (minimum 300usec for LXT971A)
1485 CONFIG_PHY_CMD_DELAY (ppc4xx)
1487 Some PHY like Intel LXT971A need extra delay after
1488 command issued before MII status register can be read
1490 - Ethernet address:
1491 CONFIG_ETHADDR
1492 CONFIG_ETH1ADDR
1493 CONFIG_ETH2ADDR
1494 CONFIG_ETH3ADDR
1495 CONFIG_ETH4ADDR
1496 CONFIG_ETH5ADDR
1498 Define a default value for Ethernet address to use
1499 for the respective Ethernet interface, in case this
1500 is not determined automatically.
1502 - IP address:
1503 CONFIG_IPADDR
1505 Define a default value for the IP address to use for
1506 the default Ethernet interface, in case this is not
1507 determined through e.g. bootp.
1508 (Environment variable "ipaddr")
1510 - Server IP address:
1511 CONFIG_SERVERIP
1513 Defines a default value for the IP address of a TFTP
1514 server to contact when using the "tftboot" command.
1515 (Environment variable "serverip")
1517 CONFIG_KEEP_SERVERADDR
1519 Keeps the server's MAC address, in the env 'serveraddr'
1520 for passing to bootargs (like Linux's netconsole option)
1522 - Gateway IP address:
1523 CONFIG_GATEWAYIP
1525 Defines a default value for the IP address of the
1526 default router where packets to other networks are
1527 sent to.
1528 (Environment variable "gatewayip")
1530 - Subnet mask:
1531 CONFIG_NETMASK
1533 Defines a default value for the subnet mask (or
1534 routing prefix) which is used to determine if an IP
1535 address belongs to the local subnet or needs to be
1536 forwarded through a router.
1537 (Environment variable "netmask")
1539 - Multicast TFTP Mode:
1540 CONFIG_MCAST_TFTP
1542 Defines whether you want to support multicast TFTP as per
1543 rfc-2090; for example to work with atftp. Lets lots of targets
1544 tftp down the same boot image concurrently. Note: the Ethernet
1545 driver in use must provide a function: mcast() to join/leave a
1546 multicast group.
1548 - BOOTP Recovery Mode:
1549 CONFIG_BOOTP_RANDOM_DELAY
1551 If you have many targets in a network that try to
1552 boot using BOOTP, you may want to avoid that all
1553 systems send out BOOTP requests at precisely the same
1554 moment (which would happen for instance at recovery
1555 from a power failure, when all systems will try to
1556 boot, thus flooding the BOOTP server. Defining
1557 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1558 inserted before sending out BOOTP requests. The
1559 following delays are inserted then:
1561 1st BOOTP request: delay 0 ... 1 sec
1562 2nd BOOTP request: delay 0 ... 2 sec
1563 3rd BOOTP request: delay 0 ... 4 sec
1564 4th and following
1565 BOOTP requests: delay 0 ... 8 sec
1567 - DHCP Advanced Options:
1568 You can fine tune the DHCP functionality by defining
1569 CONFIG_BOOTP_* symbols:
1571 CONFIG_BOOTP_SUBNETMASK
1572 CONFIG_BOOTP_GATEWAY
1573 CONFIG_BOOTP_HOSTNAME
1574 CONFIG_BOOTP_NISDOMAIN
1575 CONFIG_BOOTP_BOOTPATH
1576 CONFIG_BOOTP_BOOTFILESIZE
1577 CONFIG_BOOTP_DNS
1578 CONFIG_BOOTP_DNS2
1579 CONFIG_BOOTP_SEND_HOSTNAME
1580 CONFIG_BOOTP_NTPSERVER
1581 CONFIG_BOOTP_TIMEOFFSET
1582 CONFIG_BOOTP_VENDOREX
1584 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1585 environment variable, not the BOOTP server.
1587 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1588 serverip from a DHCP server, it is possible that more
1589 than one DNS serverip is offered to the client.
1590 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1591 serverip will be stored in the additional environment
1592 variable "dnsip2". The first DNS serverip is always
1593 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1594 is defined.
1596 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1597 to do a dynamic update of a DNS server. To do this, they
1598 need the hostname of the DHCP requester.
1599 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1600 of the "hostname" environment variable is passed as
1601 option 12 to the DHCP server.
1603 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1605 A 32bit value in microseconds for a delay between
1606 receiving a "DHCP Offer" and sending the "DHCP Request".
1607 This fixes a problem with certain DHCP servers that don't
1608 respond 100% of the time to a "DHCP request". E.g. On an
1609 AT91RM9200 processor running at 180MHz, this delay needed
1610 to be *at least* 15,000 usec before a Windows Server 2003
1611 DHCP server would reply 100% of the time. I recommend at
1612 least 50,000 usec to be safe. The alternative is to hope
1613 that one of the retries will be successful but note that
1614 the DHCP timeout and retry process takes a longer than
1615 this delay.
1617 - CDP Options:
1618 CONFIG_CDP_DEVICE_ID
1620 The device id used in CDP trigger frames.
1622 CONFIG_CDP_DEVICE_ID_PREFIX
1624 A two character string which is prefixed to the MAC address
1625 of the device.
1627 CONFIG_CDP_PORT_ID
1629 A printf format string which contains the ascii name of
1630 the port. Normally is set to "eth%d" which sets
1631 eth0 for the first Ethernet, eth1 for the second etc.
1633 CONFIG_CDP_CAPABILITIES
1635 A 32bit integer which indicates the device capabilities;
1636 0x00000010 for a normal host which does not forwards.
1638 CONFIG_CDP_VERSION
1640 An ascii string containing the version of the software.
1642 CONFIG_CDP_PLATFORM
1644 An ascii string containing the name of the platform.
1646 CONFIG_CDP_TRIGGER
1648 A 32bit integer sent on the trigger.
1650 CONFIG_CDP_POWER_CONSUMPTION
1652 A 16bit integer containing the power consumption of the
1653 device in .1 of milliwatts.
1655 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1657 A byte containing the id of the VLAN.
1659 - Status LED: CONFIG_STATUS_LED
1661 Several configurations allow to display the current
1662 status using a LED. For instance, the LED will blink
1663 fast while running U-Boot code, stop blinking as
1664 soon as a reply to a BOOTP request was received, and
1665 start blinking slow once the Linux kernel is running
1666 (supported by a status LED driver in the Linux
1667 kernel). Defining CONFIG_STATUS_LED enables this
1668 feature in U-Boot.
1670 - CAN Support: CONFIG_CAN_DRIVER
1672 Defining CONFIG_CAN_DRIVER enables CAN driver support
1673 on those systems that support this (optional)
1674 feature, like the TQM8xxL modules.
1676 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1678 These enable I2C serial bus commands. Defining either of
1679 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1680 include the appropriate I2C driver for the selected CPU.
1682 This will allow you to use i2c commands at the u-boot
1683 command line (as long as you set CONFIG_CMD_I2C in
1684 CONFIG_COMMANDS) and communicate with i2c based realtime
1685 clock chips. See common/cmd_i2c.c for a description of the
1686 command line interface.
1688 CONFIG_HARD_I2C selects a hardware I2C controller.
1690 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1691 bit-banging) driver instead of CPM or similar hardware
1692 support for I2C.
1694 There are several other quantities that must also be
1695 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1697 In both cases you will need to define CONFIG_SYS_I2C_SPEED
1698 to be the frequency (in Hz) at which you wish your i2c bus
1699 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
1700 the CPU's i2c node address).
1702 Now, the u-boot i2c code for the mpc8xx
1703 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
1704 and so its address should therefore be cleared to 0 (See,
1705 eg, MPC823e User's Manual p.16-473). So, set
1706 CONFIG_SYS_I2C_SLAVE to 0.
1708 CONFIG_SYS_I2C_INIT_MPC5XXX
1710 When a board is reset during an i2c bus transfer
1711 chips might think that the current transfer is still
1712 in progress. Reset the slave devices by sending start
1713 commands until the slave device responds.
1715 That's all that's required for CONFIG_HARD_I2C.
1717 If you use the software i2c interface (CONFIG_SOFT_I2C)
1718 then the following macros need to be defined (examples are
1719 from include/configs/lwmon.h):
1721 I2C_INIT
1723 (Optional). Any commands necessary to enable the I2C
1724 controller or configure ports.
1726 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1728 I2C_PORT
1730 (Only for MPC8260 CPU). The I/O port to use (the code
1731 assumes both bits are on the same port). Valid values
1732 are 0..3 for ports A..D.
1734 I2C_ACTIVE
1736 The code necessary to make the I2C data line active
1737 (driven). If the data line is open collector, this
1738 define can be null.
1740 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1742 I2C_TRISTATE
1744 The code necessary to make the I2C data line tri-stated
1745 (inactive). If the data line is open collector, this
1746 define can be null.
1748 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1750 I2C_READ
1752 Code that returns TRUE if the I2C data line is high,
1753 FALSE if it is low.
1755 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1757 I2C_SDA(bit)
1759 If <bit> is TRUE, sets the I2C data line high. If it
1760 is FALSE, it clears it (low).
1762 eg: #define I2C_SDA(bit) \
1763 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1764 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1766 I2C_SCL(bit)
1768 If <bit> is TRUE, sets the I2C clock line high. If it
1769 is FALSE, it clears it (low).
1771 eg: #define I2C_SCL(bit) \
1772 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1773 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1775 I2C_DELAY
1777 This delay is invoked four times per clock cycle so this
1778 controls the rate of data transfer. The data rate thus
1779 is 1 / (I2C_DELAY * 4). Often defined to be something
1780 like:
1782 #define I2C_DELAY udelay(2)
1784 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
1786 If your arch supports the generic GPIO framework (asm/gpio.h),
1787 then you may alternatively define the two GPIOs that are to be
1788 used as SCL / SDA. Any of the previous I2C_xxx macros will
1789 have GPIO-based defaults assigned to them as appropriate.
1791 You should define these to the GPIO value as given directly to
1792 the generic GPIO functions.
1794 CONFIG_SYS_I2C_INIT_BOARD
1796 When a board is reset during an i2c bus transfer
1797 chips might think that the current transfer is still
1798 in progress. On some boards it is possible to access
1799 the i2c SCLK line directly, either by using the
1800 processor pin as a GPIO or by having a second pin
1801 connected to the bus. If this option is defined a
1802 custom i2c_init_board() routine in boards/xxx/board.c
1803 is run early in the boot sequence.
1805 CONFIG_SYS_I2C_BOARD_LATE_INIT
1807 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
1808 defined a custom i2c_board_late_init() routine in
1809 boards/xxx/board.c is run AFTER the operations in i2c_init()
1810 is completed. This callpoint can be used to unreset i2c bus
1811 using CPU i2c controller register accesses for CPUs whose i2c
1812 controller provide such a method. It is called at the end of
1813 i2c_init() to allow i2c_init operations to setup the i2c bus
1814 controller on the CPU (e.g. setting bus speed & slave address).
1816 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
1818 This option enables configuration of bi_iic_fast[] flags
1819 in u-boot bd_info structure based on u-boot environment
1820 variable "i2cfast". (see also i2cfast)
1822 CONFIG_I2C_MULTI_BUS
1824 This option allows the use of multiple I2C buses, each of which
1825 must have a controller. At any point in time, only one bus is
1826 active. To switch to a different bus, use the 'i2c dev' command.
1827 Note that bus numbering is zero-based.
1829 CONFIG_SYS_I2C_NOPROBES
1831 This option specifies a list of I2C devices that will be skipped
1832 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
1833 is set, specify a list of bus-device pairs. Otherwise, specify
1834 a 1D array of device addresses
1836 e.g.
1837 #undef CONFIG_I2C_MULTI_BUS
1838 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
1840 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1842 #define CONFIG_I2C_MULTI_BUS
1843 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
1845 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1847 CONFIG_SYS_SPD_BUS_NUM
1849 If defined, then this indicates the I2C bus number for DDR SPD.
1850 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1852 CONFIG_SYS_RTC_BUS_NUM
1854 If defined, then this indicates the I2C bus number for the RTC.
1855 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1857 CONFIG_SYS_DTT_BUS_NUM
1859 If defined, then this indicates the I2C bus number for the DTT.
1860 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
1862 CONFIG_SYS_I2C_DTT_ADDR:
1864 If defined, specifies the I2C address of the DTT device.
1865 If not defined, then U-Boot uses predefined value for
1866 specified DTT device.
1868 CONFIG_FSL_I2C
1870 Define this option if you want to use Freescale's I2C driver in
1871 drivers/i2c/fsl_i2c.c.
1873 CONFIG_I2C_MUX
1875 Define this option if you have I2C devices reached over 1 .. n
1876 I2C Muxes like the pca9544a. This option addes a new I2C
1877 Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a
1878 new I2C Bus to the existing I2C Busses. If you select the
1879 new Bus with "i2c dev", u-bbot sends first the commandos for
1880 the muxes to activate this new "bus".
1882 CONFIG_I2C_MULTI_BUS must be also defined, to use this
1883 feature!
1885 Example:
1886 Adding a new I2C Bus reached over 2 pca9544a muxes
1887 The First mux with address 70 and channel 6
1888 The Second mux with address 71 and channel 4
1890 => i2c bus pca9544a:70:6:pca9544a:71:4
1892 Use the "i2c bus" command without parameter, to get a list
1893 of I2C Busses with muxes:
1895 => i2c bus
1896 Busses reached over muxes:
1897 Bus ID: 2
1898 reached over Mux(es):
1899 pca9544a@70 ch: 4
1900 Bus ID: 3
1901 reached over Mux(es):
1902 pca9544a@70 ch: 6
1903 pca9544a@71 ch: 4
1904 =>
1906 If you now switch to the new I2C Bus 3 with "i2c dev 3"
1907 u-boot first sends the command to the mux@70 to enable
1908 channel 6, and then the command to the mux@71 to enable
1909 the channel 4.
1911 After that, you can use the "normal" i2c commands as
1912 usual to communicate with your I2C devices behind
1913 the 2 muxes.
1915 This option is actually implemented for the bitbanging
1916 algorithm in common/soft_i2c.c and for the Hardware I2C
1917 Bus on the MPC8260. But it should be not so difficult
1918 to add this option to other architectures.
1920 CONFIG_SOFT_I2C_READ_REPEATED_START
1922 defining this will force the i2c_read() function in
1923 the soft_i2c driver to perform an I2C repeated start
1924 between writing the address pointer and reading the
1925 data. If this define is omitted the default behaviour
1926 of doing a stop-start sequence will be used. Most I2C
1927 devices can use either method, but some require one or
1928 the other.
1930 - SPI Support: CONFIG_SPI
1932 Enables SPI driver (so far only tested with
1933 SPI EEPROM, also an instance works with Crystal A/D and
1934 D/As on the SACSng board)
1936 CONFIG_SH_SPI
1938 Enables the driver for SPI controller on SuperH. Currently
1939 only SH7757 is supported.
1941 CONFIG_SPI_X
1943 Enables extended (16-bit) SPI EEPROM addressing.
1944 (symmetrical to CONFIG_I2C_X)
1946 CONFIG_SOFT_SPI
1948 Enables a software (bit-bang) SPI driver rather than
1949 using hardware support. This is a general purpose
1950 driver that only requires three general I/O port pins
1951 (two outputs, one input) to function. If this is
1952 defined, the board configuration must define several
1953 SPI configuration items (port pins to use, etc). For
1954 an example, see include/configs/sacsng.h.
1956 CONFIG_HARD_SPI
1958 Enables a hardware SPI driver for general-purpose reads
1959 and writes. As with CONFIG_SOFT_SPI, the board configuration
1960 must define a list of chip-select function pointers.
1961 Currently supported on some MPC8xxx processors. For an
1962 example, see include/configs/mpc8349emds.h.
1964 CONFIG_MXC_SPI
1966 Enables the driver for the SPI controllers on i.MX and MXC
1967 SoCs. Currently i.MX31/35/51 are supported.
1969 - FPGA Support: CONFIG_FPGA
1971 Enables FPGA subsystem.
1973 CONFIG_FPGA_<vendor>
1975 Enables support for specific chip vendors.
1976 (ALTERA, XILINX)
1978 CONFIG_FPGA_<family>
1980 Enables support for FPGA family.
1981 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
1983 CONFIG_FPGA_COUNT
1985 Specify the number of FPGA devices to support.
1987 CONFIG_SYS_FPGA_PROG_FEEDBACK
1989 Enable printing of hash marks during FPGA configuration.
1991 CONFIG_SYS_FPGA_CHECK_BUSY
1993 Enable checks on FPGA configuration interface busy
1994 status by the configuration function. This option
1995 will require a board or device specific function to
1996 be written.
1998 CONFIG_FPGA_DELAY
2000 If defined, a function that provides delays in the FPGA
2001 configuration driver.
2003 CONFIG_SYS_FPGA_CHECK_CTRLC
2004 Allow Control-C to interrupt FPGA configuration
2006 CONFIG_SYS_FPGA_CHECK_ERROR
2008 Check for configuration errors during FPGA bitfile
2009 loading. For example, abort during Virtex II
2010 configuration if the INIT_B line goes low (which
2011 indicated a CRC error).
2013 CONFIG_SYS_FPGA_WAIT_INIT
2015 Maximum time to wait for the INIT_B line to deassert
2016 after PROB_B has been deasserted during a Virtex II
2017 FPGA configuration sequence. The default time is 500
2018 ms.
2020 CONFIG_SYS_FPGA_WAIT_BUSY
2022 Maximum time to wait for BUSY to deassert during
2023 Virtex II FPGA configuration. The default is 5 ms.
2025 CONFIG_SYS_FPGA_WAIT_CONFIG
2027 Time to wait after FPGA configuration. The default is
2028 200 ms.
2030 - Configuration Management:
2031 CONFIG_IDENT_STRING
2033 If defined, this string will be added to the U-Boot
2034 version information (U_BOOT_VERSION)
2036 - Vendor Parameter Protection:
2038 U-Boot considers the values of the environment
2039 variables "serial#" (Board Serial Number) and
2040 "ethaddr" (Ethernet Address) to be parameters that
2041 are set once by the board vendor / manufacturer, and
2042 protects these variables from casual modification by
2043 the user. Once set, these variables are read-only,
2044 and write or delete attempts are rejected. You can
2045 change this behaviour:
2047 If CONFIG_ENV_OVERWRITE is #defined in your config
2048 file, the write protection for vendor parameters is
2049 completely disabled. Anybody can change or delete
2050 these parameters.
2052 Alternatively, if you #define _both_ CONFIG_ETHADDR
2053 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
2054 Ethernet address is installed in the environment,
2055 which can be changed exactly ONCE by the user. [The
2056 serial# is unaffected by this, i. e. it remains
2057 read-only.]
2059 - Protected RAM:
2060 CONFIG_PRAM
2062 Define this variable to enable the reservation of
2063 "protected RAM", i. e. RAM which is not overwritten
2064 by U-Boot. Define CONFIG_PRAM to hold the number of
2065 kB you want to reserve for pRAM. You can overwrite
2066 this default value by defining an environment
2067 variable "pram" to the number of kB you want to
2068 reserve. Note that the board info structure will
2069 still show the full amount of RAM. If pRAM is
2070 reserved, a new environment variable "mem" will
2071 automatically be defined to hold the amount of
2072 remaining RAM in a form that can be passed as boot
2073 argument to Linux, for instance like that:
2075 setenv bootargs ... mem=\${mem}
2076 saveenv
2078 This way you can tell Linux not to use this memory,
2079 either, which results in a memory region that will
2080 not be affected by reboots.
2082 *WARNING* If your board configuration uses automatic
2083 detection of the RAM size, you must make sure that
2084 this memory test is non-destructive. So far, the
2085 following board configurations are known to be
2086 "pRAM-clean":
2088 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
2089 HERMES, IP860, RPXlite, LWMON, LANTEC,
2090 FLAGADM, TQM8260
2092 - Error Recovery:
2093 CONFIG_PANIC_HANG
2095 Define this variable to stop the system in case of a
2096 fatal error, so that you have to reset it manually.
2097 This is probably NOT a good idea for an embedded
2098 system where you want the system to reboot
2099 automatically as fast as possible, but it may be
2100 useful during development since you can try to debug
2101 the conditions that lead to the situation.
2103 CONFIG_NET_RETRY_COUNT
2105 This variable defines the number of retries for
2106 network operations like ARP, RARP, TFTP, or BOOTP
2107 before giving up the operation. If not defined, a
2108 default value of 5 is used.
2110 CONFIG_ARP_TIMEOUT
2112 Timeout waiting for an ARP reply in milliseconds.
2114 - Command Interpreter:
2115 CONFIG_AUTO_COMPLETE
2117 Enable auto completion of commands using TAB.
2119 Note that this feature has NOT been implemented yet
2120 for the "hush" shell.
2123 CONFIG_SYS_HUSH_PARSER
2125 Define this variable to enable the "hush" shell (from
2126 Busybox) as command line interpreter, thus enabling
2127 powerful command line syntax like
2128 if...then...else...fi conditionals or `&&' and '||'
2129 constructs ("shell scripts").
2131 If undefined, you get the old, much simpler behaviour
2132 with a somewhat smaller memory footprint.
2135 CONFIG_SYS_PROMPT_HUSH_PS2
2137 This defines the secondary prompt string, which is
2138 printed when the command interpreter needs more input
2139 to complete a command. Usually "> ".
2141 Note:
2143 In the current implementation, the local variables
2144 space and global environment variables space are
2145 separated. Local variables are those you define by
2146 simply typing `name=value'. To access a local
2147 variable later on, you have write `$name' or
2148 `${name}'; to execute the contents of a variable
2149 directly type `$name' at the command prompt.
2151 Global environment variables are those you use
2152 setenv/printenv to work with. To run a command stored
2153 in such a variable, you need to use the run command,
2154 and you must not use the '$' sign to access them.
2156 To store commands and special characters in a
2157 variable, please use double quotation marks
2158 surrounding the whole text of the variable, instead
2159 of the backslashes before semicolons and special
2160 symbols.
2162 - Commandline Editing and History:
2163 CONFIG_CMDLINE_EDITING
2165 Enable editing and History functions for interactive
2166 commandline input operations
2168 - Default Environment:
2169 CONFIG_EXTRA_ENV_SETTINGS
2171 Define this to contain any number of null terminated
2172 strings (variable = value pairs) that will be part of
2173 the default environment compiled into the boot image.
2175 For example, place something like this in your
2176 board's config file:
2178 #define CONFIG_EXTRA_ENV_SETTINGS \
2179 "myvar1=value1\0" \
2180 "myvar2=value2\0"
2182 Warning: This method is based on knowledge about the
2183 internal format how the environment is stored by the
2184 U-Boot code. This is NOT an official, exported
2185 interface! Although it is unlikely that this format
2186 will change soon, there is no guarantee either.
2187 You better know what you are doing here.
2189 Note: overly (ab)use of the default environment is
2190 discouraged. Make sure to check other ways to preset
2191 the environment like the "source" command or the
2192 boot command first.
2194 - DataFlash Support:
2195 CONFIG_HAS_DATAFLASH
2197 Defining this option enables DataFlash features and
2198 allows to read/write in Dataflash via the standard
2199 commands cp, md...
2201 - Serial Flash support
2202 CONFIG_CMD_SF
2204 Defining this option enables SPI flash commands
2205 'sf probe/read/write/erase/update'.
2207 Usage requires an initial 'probe' to define the serial
2208 flash parameters, followed by read/write/erase/update
2209 commands.
2211 The following defaults may be provided by the platform
2212 to handle the common case when only a single serial
2213 flash is present on the system.
2215 CONFIG_SF_DEFAULT_BUS Bus identifier
2216 CONFIG_SF_DEFAULT_CS Chip-select
2217 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
2218 CONFIG_SF_DEFAULT_SPEED in Hz
2220 - SystemACE Support:
2221 CONFIG_SYSTEMACE
2223 Adding this option adds support for Xilinx SystemACE
2224 chips attached via some sort of local bus. The address
2225 of the chip must also be defined in the
2226 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
2228 #define CONFIG_SYSTEMACE
2229 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
2231 When SystemACE support is added, the "ace" device type
2232 becomes available to the fat commands, i.e. fatls.
2234 - TFTP Fixed UDP Port:
2235 CONFIG_TFTP_PORT
2237 If this is defined, the environment variable tftpsrcp
2238 is used to supply the TFTP UDP source port value.
2239 If tftpsrcp isn't defined, the normal pseudo-random port
2240 number generator is used.
2242 Also, the environment variable tftpdstp is used to supply
2243 the TFTP UDP destination port value. If tftpdstp isn't
2244 defined, the normal port 69 is used.
2246 The purpose for tftpsrcp is to allow a TFTP server to
2247 blindly start the TFTP transfer using the pre-configured
2248 target IP address and UDP port. This has the effect of
2249 "punching through" the (Windows XP) firewall, allowing
2250 the remainder of the TFTP transfer to proceed normally.
2251 A better solution is to properly configure the firewall,
2252 but sometimes that is not allowed.
2254 - Show boot progress:
2255 CONFIG_SHOW_BOOT_PROGRESS
2257 Defining this option allows to add some board-
2258 specific code (calling a user-provided function
2259 "show_boot_progress(int)") that enables you to show
2260 the system's boot progress on some display (for
2261 example, some LED's) on your board. At the moment,
2262 the following checkpoints are implemented:
2264 Legacy uImage format:
2266 Arg Where When
2267 1 common/cmd_bootm.c before attempting to boot an image
2268 -1 common/cmd_bootm.c Image header has bad magic number
2269 2 common/cmd_bootm.c Image header has correct magic number
2270 -2 common/cmd_bootm.c Image header has bad checksum
2271 3 common/cmd_bootm.c Image header has correct checksum
2272 -3 common/cmd_bootm.c Image data has bad checksum
2273 4 common/cmd_bootm.c Image data has correct checksum
2274 -4 common/cmd_bootm.c Image is for unsupported architecture
2275 5 common/cmd_bootm.c Architecture check OK
2276 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
2277 6 common/cmd_bootm.c Image Type check OK
2278 -6 common/cmd_bootm.c gunzip uncompression error
2279 -7 common/cmd_bootm.c Unimplemented compression type
2280 7 common/cmd_bootm.c Uncompression OK
2281 8 common/cmd_bootm.c No uncompress/copy overwrite error
2282 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
2284 9 common/image.c Start initial ramdisk verification
2285 -10 common/image.c Ramdisk header has bad magic number
2286 -11 common/image.c Ramdisk header has bad checksum
2287 10 common/image.c Ramdisk header is OK
2288 -12 common/image.c Ramdisk data has bad checksum
2289 11 common/image.c Ramdisk data has correct checksum
2290 12 common/image.c Ramdisk verification complete, start loading
2291 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
2292 13 common/image.c Start multifile image verification
2293 14 common/image.c No initial ramdisk, no multifile, continue.
2295 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
2297 -30 arch/powerpc/lib/board.c Fatal error, hang the system
2298 -31 post/post.c POST test failed, detected by post_output_backlog()
2299 -32 post/post.c POST test failed, detected by post_run_single()
2301 34 common/cmd_doc.c before loading a Image from a DOC device
2302 -35 common/cmd_doc.c Bad usage of "doc" command
2303 35 common/cmd_doc.c correct usage of "doc" command
2304 -36 common/cmd_doc.c No boot device
2305 36 common/cmd_doc.c correct boot device
2306 -37 common/cmd_doc.c Unknown Chip ID on boot device
2307 37 common/cmd_doc.c correct chip ID found, device available
2308 -38 common/cmd_doc.c Read Error on boot device
2309 38 common/cmd_doc.c reading Image header from DOC device OK
2310 -39 common/cmd_doc.c Image header has bad magic number
2311 39 common/cmd_doc.c Image header has correct magic number
2312 -40 common/cmd_doc.c Error reading Image from DOC device
2313 40 common/cmd_doc.c Image header has correct magic number
2314 41 common/cmd_ide.c before loading a Image from a IDE device
2315 -42 common/cmd_ide.c Bad usage of "ide" command
2316 42 common/cmd_ide.c correct usage of "ide" command
2317 -43 common/cmd_ide.c No boot device
2318 43 common/cmd_ide.c boot device found
2319 -44 common/cmd_ide.c Device not available
2320 44 common/cmd_ide.c Device available
2321 -45 common/cmd_ide.c wrong partition selected
2322 45 common/cmd_ide.c partition selected
2323 -46 common/cmd_ide.c Unknown partition table
2324 46 common/cmd_ide.c valid partition table found
2325 -47 common/cmd_ide.c Invalid partition type
2326 47 common/cmd_ide.c correct partition type
2327 -48 common/cmd_ide.c Error reading Image Header on boot device
2328 48 common/cmd_ide.c reading Image Header from IDE device OK
2329 -49 common/cmd_ide.c Image header has bad magic number
2330 49 common/cmd_ide.c Image header has correct magic number
2331 -50 common/cmd_ide.c Image header has bad checksum
2332 50 common/cmd_ide.c Image header has correct checksum
2333 -51 common/cmd_ide.c Error reading Image from IDE device
2334 51 common/cmd_ide.c reading Image from IDE device OK
2335 52 common/cmd_nand.c before loading a Image from a NAND device
2336 -53 common/cmd_nand.c Bad usage of "nand" command
2337 53 common/cmd_nand.c correct usage of "nand" command
2338 -54 common/cmd_nand.c No boot device
2339 54 common/cmd_nand.c boot device found
2340 -55 common/cmd_nand.c Unknown Chip ID on boot device
2341 55 common/cmd_nand.c correct chip ID found, device available
2342 -56 common/cmd_nand.c Error reading Image Header on boot device
2343 56 common/cmd_nand.c reading Image Header from NAND device OK
2344 -57 common/cmd_nand.c Image header has bad magic number
2345 57 common/cmd_nand.c Image header has correct magic number
2346 -58 common/cmd_nand.c Error reading Image from NAND device
2347 58 common/cmd_nand.c reading Image from NAND device OK
2349 -60 common/env_common.c Environment has a bad CRC, using default
2351 64 net/eth.c starting with Ethernet configuration.
2352 -64 net/eth.c no Ethernet found.
2353 65 net/eth.c Ethernet found.
2355 -80 common/cmd_net.c usage wrong
2356 80 common/cmd_net.c before calling NetLoop()
2357 -81 common/cmd_net.c some error in NetLoop() occurred
2358 81 common/cmd_net.c NetLoop() back without error
2359 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2360 82 common/cmd_net.c trying automatic boot
2361 83 common/cmd_net.c running "source" command
2362 -83 common/cmd_net.c some error in automatic boot or "source" command
2363 84 common/cmd_net.c end without errors
2365 FIT uImage format:
2367 Arg Where When
2368 100 common/cmd_bootm.c Kernel FIT Image has correct format
2369 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2370 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2371 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2372 102 common/cmd_bootm.c Kernel unit name specified
2373 -103 common/cmd_bootm.c Can't get kernel subimage node offset
2374 103 common/cmd_bootm.c Found configuration node
2375 104 common/cmd_bootm.c Got kernel subimage node offset
2376 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2377 105 common/cmd_bootm.c Kernel subimage hash verification OK
2378 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2379 106 common/cmd_bootm.c Architecture check OK
2380 -106 common/cmd_bootm.c Kernel subimage has wrong type
2381 107 common/cmd_bootm.c Kernel subimage type OK
2382 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2383 108 common/cmd_bootm.c Got kernel subimage data/size
2384 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2385 -109 common/cmd_bootm.c Can't get kernel subimage type
2386 -110 common/cmd_bootm.c Can't get kernel subimage comp
2387 -111 common/cmd_bootm.c Can't get kernel subimage os
2388 -112 common/cmd_bootm.c Can't get kernel subimage load address
2389 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2391 120 common/image.c Start initial ramdisk verification
2392 -120 common/image.c Ramdisk FIT image has incorrect format
2393 121 common/image.c Ramdisk FIT image has correct format
2394 122 common/image.c No ramdisk subimage unit name, using configuration
2395 -122 common/image.c Can't get configuration for ramdisk subimage
2396 123 common/image.c Ramdisk unit name specified
2397 -124 common/image.c Can't get ramdisk subimage node offset
2398 125 common/image.c Got ramdisk subimage node offset
2399 -125 common/image.c Ramdisk subimage hash verification failed
2400 126 common/image.c Ramdisk subimage hash verification OK
2401 -126 common/image.c Ramdisk subimage for unsupported architecture
2402 127 common/image.c Architecture check OK
2403 -127 common/image.c Can't get ramdisk subimage data/size
2404 128 common/image.c Got ramdisk subimage data/size
2405 129 common/image.c Can't get ramdisk load address
2406 -129 common/image.c Got ramdisk load address
2408 -130 common/cmd_doc.c Incorrect FIT image format
2409 131 common/cmd_doc.c FIT image format OK
2411 -140 common/cmd_ide.c Incorrect FIT image format
2412 141 common/cmd_ide.c FIT image format OK
2414 -150 common/cmd_nand.c Incorrect FIT image format
2415 151 common/cmd_nand.c FIT image format OK
2417 - Standalone program support:
2418 CONFIG_STANDALONE_LOAD_ADDR
2420 This option defines a board specific value for the
2421 address where standalone program gets loaded, thus
2422 overwriting the architecture dependent default
2423 settings.
2425 - Frame Buffer Address:
2426 CONFIG_FB_ADDR
2428 Define CONFIG_FB_ADDR if you want to use specific
2429 address for frame buffer.
2430 Then system will reserve the frame buffer address to
2431 defined address instead of lcd_setmem (this function
2432 grabs the memory for frame buffer by panel's size).
2434 Please see board_init_f function.
2436 - Automatic software updates via TFTP server
2437 CONFIG_UPDATE_TFTP
2438 CONFIG_UPDATE_TFTP_CNT_MAX
2439 CONFIG_UPDATE_TFTP_MSEC_MAX
2441 These options enable and control the auto-update feature;
2442 for a more detailed description refer to doc/README.update.
2444 - MTD Support (mtdparts command, UBI support)
2445 CONFIG_MTD_DEVICE
2447 Adds the MTD device infrastructure from the Linux kernel.
2448 Needed for mtdparts command support.
2450 CONFIG_MTD_PARTITIONS
2452 Adds the MTD partitioning infrastructure from the Linux
2453 kernel. Needed for UBI support.
2455 - SPL framework
2456 CONFIG_SPL
2457 Enable building of SPL globally.
2459 CONFIG_SPL_TEXT_BASE
2460 TEXT_BASE for linking the SPL binary.
2462 CONFIG_SPL_LDSCRIPT
2463 LDSCRIPT for linking the SPL binary.
2465 CONFIG_SPL_LIBCOMMON_SUPPORT
2466 Support for common/libcommon.o in SPL binary
2468 CONFIG_SPL_LIBDISK_SUPPORT
2469 Support for disk/libdisk.o in SPL binary
2471 CONFIG_SPL_I2C_SUPPORT
2472 Support for drivers/i2c/libi2c.o in SPL binary
2474 CONFIG_SPL_GPIO_SUPPORT
2475 Support for drivers/gpio/libgpio.o in SPL binary
2477 CONFIG_SPL_MMC_SUPPORT
2478 Support for drivers/mmc/libmmc.o in SPL binary
2480 CONFIG_SPL_SERIAL_SUPPORT
2481 Support for drivers/serial/libserial.o in SPL binary
2483 CONFIG_SPL_SPI_FLASH_SUPPORT
2484 Support for drivers/mtd/spi/libspi_flash.o in SPL binary
2486 CONFIG_SPL_SPI_SUPPORT
2487 Support for drivers/spi/libspi.o in SPL binary
2489 CONFIG_SPL_FAT_SUPPORT
2490 Support for fs/fat/libfat.o in SPL binary
2492 CONFIG_SPL_LIBGENERIC_SUPPORT
2493 Support for lib/libgeneric.o in SPL binary
2495 Modem Support:
2496 --------------
2498 [so far only for SMDK2400 boards]
2500 - Modem support enable:
2501 CONFIG_MODEM_SUPPORT
2503 - RTS/CTS Flow control enable:
2504 CONFIG_HWFLOW
2506 - Modem debug support:
2507 CONFIG_MODEM_SUPPORT_DEBUG
2509 Enables debugging stuff (char screen[1024], dbg())
2510 for modem support. Useful only with BDI2000.
2512 - Interrupt support (PPC):
2514 There are common interrupt_init() and timer_interrupt()
2515 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
2516 for CPU specific initialization. interrupt_init_cpu()
2517 should set decrementer_count to appropriate value. If
2518 CPU resets decrementer automatically after interrupt
2519 (ppc4xx) it should set decrementer_count to zero.
2520 timer_interrupt() calls timer_interrupt_cpu() for CPU
2521 specific handling. If board has watchdog / status_led
2522 / other_activity_monitor it works automatically from
2523 general timer_interrupt().
2525 - General:
2527 In the target system modem support is enabled when a
2528 specific key (key combination) is pressed during
2529 power-on. Otherwise U-Boot will boot normally
2530 (autoboot). The key_pressed() function is called from
2531 board_init(). Currently key_pressed() is a dummy
2532 function, returning 1 and thus enabling modem
2533 initialization.
2535 If there are no modem init strings in the
2536 environment, U-Boot proceed to autoboot; the
2537 previous output (banner, info printfs) will be
2538 suppressed, though.
2540 See also: doc/README.Modem
2542 Board initialization settings:
2543 ------------------------------
2545 During Initialization u-boot calls a number of board specific functions
2546 to allow the preparation of board specific prerequisites, e.g. pin setup
2547 before drivers are initialized. To enable these callbacks the
2548 following configuration macros have to be defined. Currently this is
2549 architecture specific, so please check arch/your_architecture/lib/board.c
2550 typically in board_init_f() and board_init_r().
2552 - CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
2553 - CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
2554 - CONFIG_BOARD_LATE_INIT: Call board_late_init()
2555 - CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
2557 Configuration Settings:
2558 -----------------------
2560 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
2561 undefine this when you're short of memory.
2563 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
2564 width of the commands listed in the 'help' command output.
2566 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
2567 prompt for user input.
2569 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
2571 - CONFIG_SYS_PBSIZE: Buffer size for Console output
2573 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
2575 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
2576 the application (usually a Linux kernel) when it is
2577 booted
2579 - CONFIG_SYS_BAUDRATE_TABLE:
2580 List of legal baudrate settings for this board.
2582 - CONFIG_SYS_CONSOLE_INFO_QUIET
2583 Suppress display of console information at boot.
2585 - CONFIG_SYS_CONSOLE_IS_IN_ENV
2586 If the board specific function
2587 extern int overwrite_console (void);
2588 returns 1, the stdin, stderr and stdout are switched to the
2589 serial port, else the settings in the environment are used.
2591 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
2592 Enable the call to overwrite_console().
2594 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
2595 Enable overwrite of previous console environment settings.
2597 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
2598 Begin and End addresses of the area used by the
2599 simple memory test.
2601 - CONFIG_SYS_ALT_MEMTEST:
2602 Enable an alternate, more extensive memory test.
2604 - CONFIG_SYS_MEMTEST_SCRATCH:
2605 Scratch address used by the alternate memory test
2606 You only need to set this if address zero isn't writeable
2608 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
2609 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
2610 this specified memory area will get subtracted from the top
2611 (end) of RAM and won't get "touched" at all by U-Boot. By
2612 fixing up gd->ram_size the Linux kernel should gets passed
2613 the now "corrected" memory size and won't touch it either.
2614 This should work for arch/ppc and arch/powerpc. Only Linux
2615 board ports in arch/powerpc with bootwrapper support that
2616 recalculate the memory size from the SDRAM controller setup
2617 will have to get fixed in Linux additionally.
2619 This option can be used as a workaround for the 440EPx/GRx
2620 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
2621 be touched.
2623 WARNING: Please make sure that this value is a multiple of
2624 the Linux page size (normally 4k). If this is not the case,
2625 then the end address of the Linux memory will be located at a
2626 non page size aligned address and this could cause major
2627 problems.
2629 - CONFIG_SYS_TFTP_LOADADDR:
2630 Default load address for network file downloads
2632 - CONFIG_SYS_LOADS_BAUD_CHANGE:
2633 Enable temporary baudrate change while serial download
2635 - CONFIG_SYS_SDRAM_BASE:
2636 Physical start address of SDRAM. _Must_ be 0 here.
2638 - CONFIG_SYS_MBIO_BASE:
2639 Physical start address of Motherboard I/O (if using a
2640 Cogent motherboard)
2642 - CONFIG_SYS_FLASH_BASE:
2643 Physical start address of Flash memory.
2645 - CONFIG_SYS_MONITOR_BASE:
2646 Physical start address of boot monitor code (set by
2647 make config files to be same as the text base address
2648 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
2649 CONFIG_SYS_FLASH_BASE when booting from flash.
2651 - CONFIG_SYS_MONITOR_LEN:
2652 Size of memory reserved for monitor code, used to
2653 determine _at_compile_time_ (!) if the environment is
2654 embedded within the U-Boot image, or in a separate
2655 flash sector.
2657 - CONFIG_SYS_MALLOC_LEN:
2658 Size of DRAM reserved for malloc() use.
2660 - CONFIG_SYS_BOOTM_LEN:
2661 Normally compressed uImages are limited to an
2662 uncompressed size of 8 MBytes. If this is not enough,
2663 you can define CONFIG_SYS_BOOTM_LEN in your board config file
2664 to adjust this setting to your needs.
2666 - CONFIG_SYS_BOOTMAPSZ:
2667 Maximum size of memory mapped by the startup code of
2668 the Linux kernel; all data that must be processed by
2669 the Linux kernel (bd_info, boot arguments, FDT blob if
2670 used) must be put below this limit, unless "bootm_low"
2671 enviroment variable is defined and non-zero. In such case
2672 all data for the Linux kernel must be between "bootm_low"
2673 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
2674 variable "bootm_mapsize" will override the value of
2675 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
2676 then the value in "bootm_size" will be used instead.
2678 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
2679 Enable initrd_high functionality. If defined then the
2680 initrd_high feature is enabled and the bootm ramdisk subcommand
2681 is enabled.
2683 - CONFIG_SYS_BOOT_GET_CMDLINE:
2684 Enables allocating and saving kernel cmdline in space between
2685 "bootm_low" and "bootm_low" + BOOTMAPSZ.
2687 - CONFIG_SYS_BOOT_GET_KBD:
2688 Enables allocating and saving a kernel copy of the bd_info in
2689 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
2691 - CONFIG_SYS_MAX_FLASH_BANKS:
2692 Max number of Flash memory banks
2694 - CONFIG_SYS_MAX_FLASH_SECT:
2695 Max number of sectors on a Flash chip
2697 - CONFIG_SYS_FLASH_ERASE_TOUT:
2698 Timeout for Flash erase operations (in ms)
2700 - CONFIG_SYS_FLASH_WRITE_TOUT:
2701 Timeout for Flash write operations (in ms)
2703 - CONFIG_SYS_FLASH_LOCK_TOUT
2704 Timeout for Flash set sector lock bit operation (in ms)
2706 - CONFIG_SYS_FLASH_UNLOCK_TOUT
2707 Timeout for Flash clear lock bits operation (in ms)
2709 - CONFIG_SYS_FLASH_PROTECTION
2710 If defined, hardware flash sectors protection is used
2711 instead of U-Boot software protection.
2713 - CONFIG_SYS_DIRECT_FLASH_TFTP:
2715 Enable TFTP transfers directly to flash memory;
2716 without this option such a download has to be
2717 performed in two steps: (1) download to RAM, and (2)
2718 copy from RAM to flash.
2720 The two-step approach is usually more reliable, since
2721 you can check if the download worked before you erase
2722 the flash, but in some situations (when system RAM is
2723 too limited to allow for a temporary copy of the
2724 downloaded image) this option may be very useful.
2726 - CONFIG_SYS_FLASH_CFI:
2727 Define if the flash driver uses extra elements in the
2728 common flash structure for storing flash geometry.
2730 - CONFIG_FLASH_CFI_DRIVER
2731 This option also enables the building of the cfi_flash driver
2732 in the drivers directory
2734 - CONFIG_FLASH_CFI_MTD
2735 This option enables the building of the cfi_mtd driver
2736 in the drivers directory. The driver exports CFI flash
2737 to the MTD layer.
2739 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
2740 Use buffered writes to flash.
2742 - CONFIG_FLASH_SPANSION_S29WS_N
2743 s29ws-n MirrorBit flash has non-standard addresses for buffered
2744 write commands.
2746 - CONFIG_SYS_FLASH_QUIET_TEST
2747 If this option is defined, the common CFI flash doesn't
2748 print it's warning upon not recognized FLASH banks. This
2749 is useful, if some of the configured banks are only
2750 optionally available.
2752 - CONFIG_FLASH_SHOW_PROGRESS
2753 If defined (must be an integer), print out countdown
2754 digits and dots. Recommended value: 45 (9..1) for 80
2755 column displays, 15 (3..1) for 40 column displays.
2757 - CONFIG_SYS_RX_ETH_BUFFER:
2758 Defines the number of Ethernet receive buffers. On some
2759 Ethernet controllers it is recommended to set this value
2760 to 8 or even higher (EEPRO100 or 405 EMAC), since all
2761 buffers can be full shortly after enabling the interface
2762 on high Ethernet traffic.
2763 Defaults to 4 if not defined.
2765 - CONFIG_ENV_MAX_ENTRIES
2767 Maximum number of entries in the hash table that is used
2768 internally to store the environment settings. The default
2769 setting is supposed to be generous and should work in most
2770 cases. This setting can be used to tune behaviour; see
2771 lib/hashtable.c for details.
2773 The following definitions that deal with the placement and management
2774 of environment data (variable area); in general, we support the
2775 following configurations:
2777 - CONFIG_BUILD_ENVCRC:
2779 Builds up envcrc with the target environment so that external utils
2780 may easily extract it and embed it in final U-Boot images.
2782 - CONFIG_ENV_IS_IN_FLASH:
2784 Define this if the environment is in flash memory.
2786 a) The environment occupies one whole flash sector, which is
2787 "embedded" in the text segment with the U-Boot code. This
2788 happens usually with "bottom boot sector" or "top boot
2789 sector" type flash chips, which have several smaller
2790 sectors at the start or the end. For instance, such a
2791 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
2792 such a case you would place the environment in one of the
2793 4 kB sectors - with U-Boot code before and after it. With
2794 "top boot sector" type flash chips, you would put the
2795 environment in one of the last sectors, leaving a gap
2796 between U-Boot and the environment.
2798 - CONFIG_ENV_OFFSET:
2800 Offset of environment data (variable area) to the
2801 beginning of flash memory; for instance, with bottom boot
2802 type flash chips the second sector can be used: the offset
2803 for this sector is given here.
2805 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
2807 - CONFIG_ENV_ADDR:
2809 This is just another way to specify the start address of
2810 the flash sector containing the environment (instead of
2811 CONFIG_ENV_OFFSET).
2813 - CONFIG_ENV_SECT_SIZE:
2815 Size of the sector containing the environment.
2818 b) Sometimes flash chips have few, equal sized, BIG sectors.
2819 In such a case you don't want to spend a whole sector for
2820 the environment.
2822 - CONFIG_ENV_SIZE:
2824 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
2825 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
2826 of this flash sector for the environment. This saves
2827 memory for the RAM copy of the environment.
2829 It may also save flash memory if you decide to use this
2830 when your environment is "embedded" within U-Boot code,
2831 since then the remainder of the flash sector could be used
2832 for U-Boot code. It should be pointed out that this is
2833 STRONGLY DISCOURAGED from a robustness point of view:
2834 updating the environment in flash makes it always
2835 necessary to erase the WHOLE sector. If something goes
2836 wrong before the contents has been restored from a copy in
2837 RAM, your target system will be dead.
2839 - CONFIG_ENV_ADDR_REDUND
2840 CONFIG_ENV_SIZE_REDUND
2842 These settings describe a second storage area used to hold
2843 a redundant copy of the environment data, so that there is
2844 a valid backup copy in case there is a power failure during
2845 a "saveenv" operation.
2847 BE CAREFUL! Any changes to the flash layout, and some changes to the
2848 source code will make it necessary to adapt <board>/u-boot.lds*
2849 accordingly!
2852 - CONFIG_ENV_IS_IN_NVRAM:
2854 Define this if you have some non-volatile memory device
2855 (NVRAM, battery buffered SRAM) which you want to use for the
2856 environment.
2858 - CONFIG_ENV_ADDR:
2859 - CONFIG_ENV_SIZE:
2861 These two #defines are used to determine the memory area you
2862 want to use for environment. It is assumed that this memory
2863 can just be read and written to, without any special
2864 provision.
2866 BE CAREFUL! The first access to the environment happens quite early
2867 in U-Boot initalization (when we try to get the setting of for the
2868 console baudrate). You *MUST* have mapped your NVRAM area then, or
2869 U-Boot will hang.
2871 Please note that even with NVRAM we still use a copy of the
2872 environment in RAM: we could work on NVRAM directly, but we want to
2873 keep settings there always unmodified except somebody uses "saveenv"
2874 to save the current settings.
2877 - CONFIG_ENV_IS_IN_EEPROM:
2879 Use this if you have an EEPROM or similar serial access
2880 device and a driver for it.
2882 - CONFIG_ENV_OFFSET:
2883 - CONFIG_ENV_SIZE:
2885 These two #defines specify the offset and size of the
2886 environment area within the total memory of your EEPROM.
2888 - CONFIG_SYS_I2C_EEPROM_ADDR:
2889 If defined, specified the chip address of the EEPROM device.
2890 The default address is zero.
2892 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
2893 If defined, the number of bits used to address bytes in a
2894 single page in the EEPROM device. A 64 byte page, for example
2895 would require six bits.
2897 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
2898 If defined, the number of milliseconds to delay between
2899 page writes. The default is zero milliseconds.
2901 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
2902 The length in bytes of the EEPROM memory array address. Note
2903 that this is NOT the chip address length!
2905 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
2906 EEPROM chips that implement "address overflow" are ones
2907 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
2908 address and the extra bits end up in the "chip address" bit
2909 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
2910 byte chips.
2912 Note that we consider the length of the address field to
2913 still be one byte because the extra address bits are hidden
2914 in the chip address.
2916 - CONFIG_SYS_EEPROM_SIZE:
2917 The size in bytes of the EEPROM device.
2919 - CONFIG_ENV_EEPROM_IS_ON_I2C
2920 define this, if you have I2C and SPI activated, and your
2921 EEPROM, which holds the environment, is on the I2C bus.
2923 - CONFIG_I2C_ENV_EEPROM_BUS
2924 if you have an Environment on an EEPROM reached over
2925 I2C muxes, you can define here, how to reach this
2926 EEPROM. For example:
2928 #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0"
2930 EEPROM which holds the environment, is reached over
2931 a pca9547 i2c mux with address 0x70, channel 3.
2933 - CONFIG_ENV_IS_IN_DATAFLASH:
2935 Define this if you have a DataFlash memory device which you
2936 want to use for the environment.
2938 - CONFIG_ENV_OFFSET:
2939 - CONFIG_ENV_ADDR:
2940 - CONFIG_ENV_SIZE:
2942 These three #defines specify the offset and size of the
2943 environment area within the total memory of your DataFlash placed
2944 at the specified address.
2946 - CONFIG_ENV_IS_IN_NAND:
2948 Define this if you have a NAND device which you want to use
2949 for the environment.
2951 - CONFIG_ENV_OFFSET:
2952 - CONFIG_ENV_SIZE:
2954 These two #defines specify the offset and size of the environment
2955 area within the first NAND device. CONFIG_ENV_OFFSET must be
2956 aligned to an erase block boundary.
2958 - CONFIG_ENV_OFFSET_REDUND (optional):
2960 This setting describes a second storage area of CONFIG_ENV_SIZE
2961 size used to hold a redundant copy of the environment data, so
2962 that there is a valid backup copy in case there is a power failure
2963 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
2964 aligned to an erase block boundary.
2966 - CONFIG_ENV_RANGE (optional):
2968 Specifies the length of the region in which the environment
2969 can be written. This should be a multiple of the NAND device's
2970 block size. Specifying a range with more erase blocks than
2971 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
2972 the range to be avoided.
2974 - CONFIG_ENV_OFFSET_OOB (optional):
2976 Enables support for dynamically retrieving the offset of the
2977 environment from block zero's out-of-band data. The
2978 "nand env.oob" command can be used to record this offset.
2979 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
2980 using CONFIG_ENV_OFFSET_OOB.
2982 - CONFIG_NAND_ENV_DST
2984 Defines address in RAM to which the nand_spl code should copy the
2985 environment. If redundant environment is used, it will be copied to
2986 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
2988 - CONFIG_SYS_SPI_INIT_OFFSET
2990 Defines offset to the initial SPI buffer area in DPRAM. The
2991 area is used at an early stage (ROM part) if the environment
2992 is configured to reside in the SPI EEPROM: We need a 520 byte
2993 scratch DPRAM area. It is used between the two initialization
2994 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
2995 to be a good choice since it makes it far enough from the
2996 start of the data area as well as from the stack pointer.
2998 Please note that the environment is read-only until the monitor
2999 has been relocated to RAM and a RAM copy of the environment has been
3000 created; also, when using EEPROM you will have to use getenv_f()
3001 until then to read environment variables.
3003 The environment is protected by a CRC32 checksum. Before the monitor
3004 is relocated into RAM, as a result of a bad CRC you will be working
3005 with the compiled-in default environment - *silently*!!! [This is
3006 necessary, because the first environment variable we need is the
3007 "baudrate" setting for the console - if we have a bad CRC, we don't
3008 have any device yet where we could complain.]
3010 Note: once the monitor has been relocated, then it will complain if
3011 the default environment is used; a new CRC is computed as soon as you
3012 use the "saveenv" command to store a valid environment.
3014 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
3015 Echo the inverted Ethernet link state to the fault LED.
3017 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
3018 also needs to be defined.
3020 - CONFIG_SYS_FAULT_MII_ADDR:
3021 MII address of the PHY to check for the Ethernet link state.
3023 - CONFIG_NS16550_MIN_FUNCTIONS:
3024 Define this if you desire to only have use of the NS16550_init
3025 and NS16550_putc functions for the serial driver located at
3026 drivers/serial/ns16550.c. This option is useful for saving
3027 space for already greatly restricted images, including but not
3028 limited to NAND_SPL configurations.
3030 Low Level (hardware related) configuration options:
3031 ---------------------------------------------------
3033 - CONFIG_SYS_CACHELINE_SIZE:
3034 Cache Line Size of the CPU.
3036 - CONFIG_SYS_DEFAULT_IMMR:
3037 Default address of the IMMR after system reset.
3039 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
3040 and RPXsuper) to be able to adjust the position of
3041 the IMMR register after a reset.
3043 - CONFIG_SYS_CCSRBAR_DEFAULT:
3044 Default (power-on reset) physical address of CCSR on Freescale
3045 PowerPC SOCs.
3047 - CONFIG_SYS_CCSRBAR:
3048 Virtual address of CCSR. On a 32-bit build, this is typically
3049 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
3051 CONFIG_SYS_DEFAULT_IMMR must also be set to this value,
3052 for cross-platform code that uses that macro instead.
3054 - CONFIG_SYS_CCSRBAR_PHYS:
3055 Physical address of CCSR. CCSR can be relocated to a new
3056 physical address, if desired. In this case, this macro should
3057 be set to that address. Otherwise, it should be set to the
3058 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
3059 is typically relocated on 36-bit builds. It is recommended
3060 that this macro be defined via the _HIGH and _LOW macros:
3062 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
3063 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
3065 - CONFIG_SYS_CCSRBAR_PHYS_HIGH:
3066 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
3067 either 0 (32-bit build) or 0xF (36-bit build). This macro is
3068 used in assembly code, so it must not contain typecasts or
3069 integer size suffixes (e.g. "ULL").
3071 - CONFIG_SYS_CCSRBAR_PHYS_LOW:
3072 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
3073 used in assembly code, so it must not contain typecasts or
3074 integer size suffixes (e.g. "ULL").
3076 - CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
3077 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
3078 forced to a value that ensures that CCSR is not relocated.
3080 - Floppy Disk Support:
3081 CONFIG_SYS_FDC_DRIVE_NUMBER
3083 the default drive number (default value 0)
3085 CONFIG_SYS_ISA_IO_STRIDE
3087 defines the spacing between FDC chipset registers
3088 (default value 1)
3090 CONFIG_SYS_ISA_IO_OFFSET
3092 defines the offset of register from address. It
3093 depends on which part of the data bus is connected to
3094 the FDC chipset. (default value 0)
3096 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
3097 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
3098 default value.
3100 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
3101 fdc_hw_init() is called at the beginning of the FDC
3102 setup. fdc_hw_init() must be provided by the board
3103 source code. It is used to make hardware dependant
3104 initializations.
3106 - CONFIG_IDE_AHB:
3107 Most IDE controllers were designed to be connected with PCI
3108 interface. Only few of them were designed for AHB interface.
3109 When software is doing ATA command and data transfer to
3110 IDE devices through IDE-AHB controller, some additional
3111 registers accessing to these kind of IDE-AHB controller
3112 is requierd.
3114 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
3115 DO NOT CHANGE unless you know exactly what you're
3116 doing! (11-4) [MPC8xx/82xx systems only]
3118 - CONFIG_SYS_INIT_RAM_ADDR:
3120 Start address of memory area that can be used for
3121 initial data and stack; please note that this must be
3122 writable memory that is working WITHOUT special
3123 initialization, i. e. you CANNOT use normal RAM which
3124 will become available only after programming the
3125 memory controller and running certain initialization
3126 sequences.
3128 U-Boot uses the following memory types:
3129 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
3130 - MPC824X: data cache
3131 - PPC4xx: data cache
3133 - CONFIG_SYS_GBL_DATA_OFFSET:
3135 Offset of the initial data structure in the memory
3136 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
3137 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
3138 data is located at the end of the available space
3139 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
3140 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
3141 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
3142 CONFIG_SYS_GBL_DATA_OFFSET) downward.
3144 Note:
3145 On the MPC824X (or other systems that use the data
3146 cache for initial memory) the address chosen for
3147 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
3148 point to an otherwise UNUSED address space between
3149 the top of RAM and the start of the PCI space.
3151 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
3153 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
3155 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
3157 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
3159 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
3161 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
3163 - CONFIG_SYS_OR_TIMING_SDRAM:
3164 SDRAM timing
3166 - CONFIG_SYS_MAMR_PTA:
3167 periodic timer for refresh
3169 - CONFIG_SYS_DER: Debug Event Register (37-47)
3171 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
3172 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
3173 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
3174 CONFIG_SYS_BR1_PRELIM:
3175 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
3177 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
3178 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
3179 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
3180 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
3182 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
3183 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
3184 Machine Mode Register and Memory Periodic Timer
3185 Prescaler definitions (SDRAM timing)
3187 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
3188 enable I2C microcode relocation patch (MPC8xx);
3189 define relocation offset in DPRAM [DSP2]
3191 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
3192 enable SMC microcode relocation patch (MPC8xx);
3193 define relocation offset in DPRAM [SMC1]
3195 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
3196 enable SPI microcode relocation patch (MPC8xx);
3197 define relocation offset in DPRAM [SCC4]
3199 - CONFIG_SYS_USE_OSCCLK:
3200 Use OSCM clock mode on MBX8xx board. Be careful,
3201 wrong setting might damage your board. Read
3202 doc/README.MBX before setting this variable!
3204 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
3205 Offset of the bootmode word in DPRAM used by post
3206 (Power On Self Tests). This definition overrides
3207 #define'd default value in commproc.h resp.
3208 cpm_8260.h.
3210 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
3211 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
3212 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
3213 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
3214 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
3215 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
3216 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
3217 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
3218 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
3220 - CONFIG_PCI_DISABLE_PCIE:
3221 Disable PCI-Express on systems where it is supported but not
3222 required.
3224 - CONFIG_SYS_SRIO:
3225 Chip has SRIO or not
3227 - CONFIG_SRIO1:
3228 Board has SRIO 1 port available
3230 - CONFIG_SRIO2:
3231 Board has SRIO 2 port available
3233 - CONFIG_SYS_SRIOn_MEM_VIRT:
3234 Virtual Address of SRIO port 'n' memory region
3236 - CONFIG_SYS_SRIOn_MEM_PHYS:
3237 Physical Address of SRIO port 'n' memory region
3239 - CONFIG_SYS_SRIOn_MEM_SIZE:
3240 Size of SRIO port 'n' memory region
3242 - CONFIG_SYS_NDFC_16
3243 Defined to tell the NDFC that the NAND chip is using a
3244 16 bit bus.
3246 - CONFIG_SYS_NDFC_EBC0_CFG
3247 Sets the EBC0_CFG register for the NDFC. If not defined
3248 a default value will be used.
3250 - CONFIG_SPD_EEPROM
3251 Get DDR timing information from an I2C EEPROM. Common
3252 with pluggable memory modules such as SODIMMs
3254 SPD_EEPROM_ADDRESS
3255 I2C address of the SPD EEPROM
3257 - CONFIG_SYS_SPD_BUS_NUM
3258 If SPD EEPROM is on an I2C bus other than the first
3259 one, specify here. Note that the value must resolve
3260 to something your driver can deal with.
3262 - CONFIG_SYS_DDR_RAW_TIMING
3263 Get DDR timing information from other than SPD. Common with
3264 soldered DDR chips onboard without SPD. DDR raw timing
3265 parameters are extracted from datasheet and hard-coded into
3266 header files or board specific files.
3268 - CONFIG_FSL_DDR_INTERACTIVE
3269 Enable interactive DDR debugging. See doc/README.fsl-ddr.
3271 - CONFIG_SYS_83XX_DDR_USES_CS0
3272 Only for 83xx systems. If specified, then DDR should
3273 be configured using CS0 and CS1 instead of CS2 and CS3.
3275 - CONFIG_ETHER_ON_FEC[12]
3276 Define to enable FEC[12] on a 8xx series processor.
3278 - CONFIG_FEC[12]_PHY
3279 Define to the hardcoded PHY address which corresponds
3280 to the given FEC; i. e.
3281 #define CONFIG_FEC1_PHY 4
3282 means that the PHY with address 4 is connected to FEC1
3284 When set to -1, means to probe for first available.
3286 - CONFIG_FEC[12]_PHY_NORXERR
3287 The PHY does not have a RXERR line (RMII only).
3288 (so program the FEC to ignore it).
3290 - CONFIG_RMII
3291 Enable RMII mode for all FECs.
3292 Note that this is a global option, we can't
3293 have one FEC in standard MII mode and another in RMII mode.
3295 - CONFIG_CRC32_VERIFY
3296 Add a verify option to the crc32 command.
3297 The syntax is:
3299 => crc32 -v <address> <count> <crc32>
3301 Where address/count indicate a memory area
3302 and crc32 is the correct crc32 which the
3303 area should have.
3305 - CONFIG_LOOPW
3306 Add the "loopw" memory command. This only takes effect if
3307 the memory commands are activated globally (CONFIG_CMD_MEM).
3309 - CONFIG_MX_CYCLIC
3310 Add the "mdc" and "mwc" memory commands. These are cyclic
3311 "md/mw" commands.
3312 Examples:
3314 => mdc.b 10 4 500
3315 This command will print 4 bytes (10,11,12,13) each 500 ms.
3317 => mwc.l 100 12345678 10
3318 This command will write 12345678 to address 100 all 10 ms.
3320 This only takes effect if the memory commands are activated
3321 globally (CONFIG_CMD_MEM).
3323 - CONFIG_SKIP_LOWLEVEL_INIT
3324 [ARM, NDS32, MIPS only] If this variable is defined, then certain
3325 low level initializations (like setting up the memory
3326 controller) are omitted and/or U-Boot does not
3327 relocate itself into RAM.
3329 Normally this variable MUST NOT be defined. The only
3330 exception is when U-Boot is loaded (to RAM) by some
3331 other boot loader or by a debugger which performs
3332 these initializations itself.
3334 - CONFIG_SPL_BUILD
3335 Modifies the behaviour of start.S when compiling a loader
3336 that is executed before the actual U-Boot. E.g. when
3337 compiling a NAND SPL.
3339 - CONFIG_SYS_NAND_HW_ECC_OOBFIRST
3340 define this, if you want to read first the oob data
3341 and then the data. This is used for example on
3342 davinci plattforms.
3344 - CONFIG_USE_ARCH_MEMCPY
3345 CONFIG_USE_ARCH_MEMSET
3346 If these options are used a optimized version of memcpy/memset will
3347 be used if available. These functions may be faster under some
3348 conditions but may increase the binary size.
3350 Freescale QE/FMAN Firmware Support:
3351 -----------------------------------
3353 The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
3354 loading of "firmware", which is encoded in the QE firmware binary format.
3355 This firmware often needs to be loaded during U-Boot booting, so macros
3356 are used to identify the storage device (NOR flash, SPI, etc) and the address
3357 within that device.
3359 - CONFIG_SYS_QE_FMAN_FW_ADDR
3360 The address in the storage device where the firmware is located. The
3361 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
3362 is also specified.
3364 - CONFIG_SYS_QE_FMAN_FW_LENGTH
3365 The maximum possible size of the firmware. The firmware binary format
3366 has a field that specifies the actual size of the firmware, but it
3367 might not be possible to read any part of the firmware unless some
3368 local storage is allocated to hold the entire firmware first.
3370 - CONFIG_SYS_QE_FMAN_FW_IN_NOR
3371 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
3372 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
3373 virtual address in NOR flash.
3375 - CONFIG_SYS_QE_FMAN_FW_IN_NAND
3376 Specifies that QE/FMAN firmware is located in NAND flash.
3377 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
3379 - CONFIG_SYS_QE_FMAN_FW_IN_MMC
3380 Specifies that QE/FMAN firmware is located on the primary SD/MMC
3381 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
3383 - CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH
3384 Specifies that QE/FMAN firmware is located on the primary SPI
3385 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
3388 Building the Software:
3389 ======================
3391 Building U-Boot has been tested in several native build environments
3392 and in many different cross environments. Of course we cannot support
3393 all possibly existing versions of cross development tools in all
3394 (potentially obsolete) versions. In case of tool chain problems we
3395 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
3396 which is extensively used to build and test U-Boot.
3398 If you are not using a native environment, it is assumed that you
3399 have GNU cross compiling tools available in your path. In this case,
3400 you must set the environment variable CROSS_COMPILE in your shell.
3401 Note that no changes to the Makefile or any other source files are
3402 necessary. For example using the ELDK on a 4xx CPU, please enter:
3404 $ CROSS_COMPILE=ppc_4xx-
3405 $ export CROSS_COMPILE
3407 Note: If you wish to generate Windows versions of the utilities in
3408 the tools directory you can use the MinGW toolchain
3409 (http://www.mingw.org). Set your HOST tools to the MinGW
3410 toolchain and execute 'make tools'. For example:
3412 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
3414 Binaries such as tools/mkimage.exe will be created which can
3415 be executed on computers running Windows.
3417 U-Boot is intended to be simple to build. After installing the
3418 sources you must configure U-Boot for one specific board type. This
3419 is done by typing:
3421 make NAME_config
3423 where "NAME_config" is the name of one of the existing configu-
3424 rations; see the main Makefile for supported names.
3426 Note: for some board special configuration names may exist; check if
3427 additional information is available from the board vendor; for
3428 instance, the TQM823L systems are available without (standard)
3429 or with LCD support. You can select such additional "features"
3430 when choosing the configuration, i. e.
3432 make TQM823L_config
3433 - will configure for a plain TQM823L, i. e. no LCD support
3435 make TQM823L_LCD_config
3436 - will configure for a TQM823L with U-Boot console on LCD
3438 etc.
3441 Finally, type "make all", and you should get some working U-Boot
3442 images ready for download to / installation on your system:
3444 - "u-boot.bin" is a raw binary image
3445 - "u-boot" is an image in ELF binary format
3446 - "u-boot.srec" is in Motorola S-Record format
3448 By default the build is performed locally and the objects are saved
3449 in the source directory. One of the two methods can be used to change
3450 this behavior and build U-Boot to some external directory:
3452 1. Add O= to the make command line invocations:
3454 make O=/tmp/build distclean
3455 make O=/tmp/build NAME_config
3456 make O=/tmp/build all
3458 2. Set environment variable BUILD_DIR to point to the desired location:
3460 export BUILD_DIR=/tmp/build
3461 make distclean
3462 make NAME_config
3463 make all
3465 Note that the command line "O=" setting overrides the BUILD_DIR environment
3466 variable.
3469 Please be aware that the Makefiles assume you are using GNU make, so
3470 for instance on NetBSD you might need to use "gmake" instead of
3471 native "make".
3474 If the system board that you have is not listed, then you will need
3475 to port U-Boot to your hardware platform. To do this, follow these
3476 steps:
3478 1. Add a new configuration option for your board to the toplevel
3479 "Makefile" and to the "MAKEALL" script, using the existing
3480 entries as examples. Note that here and at many other places
3481 boards and other names are listed in alphabetical sort order. Please
3482 keep this order.
3483 2. Create a new directory to hold your board specific code. Add any
3484 files you need. In your board directory, you will need at least
3485 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
3486 3. Create a new configuration file "include/configs/<board>.h" for
3487 your board
3488 3. If you're porting U-Boot to a new CPU, then also create a new
3489 directory to hold your CPU specific code. Add any files you need.
3490 4. Run "make <board>_config" with your new name.
3491 5. Type "make", and you should get a working "u-boot.srec" file
3492 to be installed on your target system.
3493 6. Debug and solve any problems that might arise.
3494 [Of course, this last step is much harder than it sounds.]
3497 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
3498 ==============================================================
3500 If you have modified U-Boot sources (for instance added a new board
3501 or support for new devices, a new CPU, etc.) you are expected to
3502 provide feedback to the other developers. The feedback normally takes
3503 the form of a "patch", i. e. a context diff against a certain (latest
3504 official or latest in the git repository) version of U-Boot sources.
3506 But before you submit such a patch, please verify that your modifi-
3507 cation did not break existing code. At least make sure that *ALL* of
3508 the supported boards compile WITHOUT ANY compiler warnings. To do so,
3509 just run the "MAKEALL" script, which will configure and build U-Boot
3510 for ALL supported system. Be warned, this will take a while. You can
3511 select which (cross) compiler to use by passing a `CROSS_COMPILE'
3512 environment variable to the script, i. e. to use the ELDK cross tools
3513 you can type
3515 CROSS_COMPILE=ppc_8xx- MAKEALL
3517 or to build on a native PowerPC system you can type
3519 CROSS_COMPILE=' ' MAKEALL
3521 When using the MAKEALL script, the default behaviour is to build
3522 U-Boot in the source directory. This location can be changed by
3523 setting the BUILD_DIR environment variable. Also, for each target
3524 built, the MAKEALL script saves two log files (<target>.ERR and
3525 <target>.MAKEALL) in the <source dir>/LOG directory. This default
3526 location can be changed by setting the MAKEALL_LOGDIR environment
3527 variable. For example:
3529 export BUILD_DIR=/tmp/build
3530 export MAKEALL_LOGDIR=/tmp/log
3531 CROSS_COMPILE=ppc_8xx- MAKEALL
3533 With the above settings build objects are saved in the /tmp/build,
3534 log files are saved in the /tmp/log and the source tree remains clean
3535 during the whole build process.
3538 See also "U-Boot Porting Guide" below.
3541 Monitor Commands - Overview:
3542 ============================
3544 go - start application at address 'addr'
3545 run - run commands in an environment variable
3546 bootm - boot application image from memory
3547 bootp - boot image via network using BootP/TFTP protocol
3548 tftpboot- boot image via network using TFTP protocol
3549 and env variables "ipaddr" and "serverip"
3550 (and eventually "gatewayip")
3551 tftpput - upload a file via network using TFTP protocol
3552 rarpboot- boot image via network using RARP/TFTP protocol
3553 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
3554 loads - load S-Record file over serial line
3555 loadb - load binary file over serial line (kermit mode)
3556 md - memory display
3557 mm - memory modify (auto-incrementing)
3558 nm - memory modify (constant address)
3559 mw - memory write (fill)
3560 cp - memory copy
3561 cmp - memory compare
3562 crc32 - checksum calculation
3563 i2c - I2C sub-system
3564 sspi - SPI utility commands
3565 base - print or set address offset
3566 printenv- print environment variables
3567 setenv - set environment variables
3568 saveenv - save environment variables to persistent storage
3569 protect - enable or disable FLASH write protection
3570 erase - erase FLASH memory
3571 flinfo - print FLASH memory information
3572 bdinfo - print Board Info structure
3573 iminfo - print header information for application image
3574 coninfo - print console devices and informations
3575 ide - IDE sub-system
3576 loop - infinite loop on address range
3577 loopw - infinite write loop on address range
3578 mtest - simple RAM test
3579 icache - enable or disable instruction cache
3580 dcache - enable or disable data cache
3581 reset - Perform RESET of the CPU
3582 echo - echo args to console
3583 version - print monitor version
3584 help - print online help
3585 ? - alias for 'help'
3588 Monitor Commands - Detailed Description:
3589 ========================================
3591 TODO.
3593 For now: just type "help <command>".
3596 Environment Variables:
3597 ======================
3599 U-Boot supports user configuration using Environment Variables which
3600 can be made persistent by saving to Flash memory.
3602 Environment Variables are set using "setenv", printed using
3603 "printenv", and saved to Flash using "saveenv". Using "setenv"
3604 without a value can be used to delete a variable from the
3605 environment. As long as you don't save the environment you are
3606 working with an in-memory copy. In case the Flash area containing the
3607 environment is erased by accident, a default environment is provided.
3609 Some configuration options can be set using Environment Variables.
3611 List of environment variables (most likely not complete):
3613 baudrate - see CONFIG_BAUDRATE
3615 bootdelay - see CONFIG_BOOTDELAY
3617 bootcmd - see CONFIG_BOOTCOMMAND
3619 bootargs - Boot arguments when booting an RTOS image
3621 bootfile - Name of the image to load with TFTP
3623 bootm_low - Memory range available for image processing in the bootm
3624 command can be restricted. This variable is given as
3625 a hexadecimal number and defines lowest address allowed
3626 for use by the bootm command. See also "bootm_size"
3627 environment variable. Address defined by "bootm_low" is
3628 also the base of the initial memory mapping for the Linux
3629 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
3630 bootm_mapsize.
3632 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
3633 This variable is given as a hexadecimal number and it
3634 defines the size of the memory region starting at base
3635 address bootm_low that is accessible by the Linux kernel
3636 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
3637 as the default value if it is defined, and bootm_size is
3638 used otherwise.
3640 bootm_size - Memory range available for image processing in the bootm
3641 command can be restricted. This variable is given as
3642 a hexadecimal number and defines the size of the region
3643 allowed for use by the bootm command. See also "bootm_low"
3644 environment variable.
3646 updatefile - Location of the software update file on a TFTP server, used
3647 by the automatic software update feature. Please refer to
3648 documentation in doc/README.update for more details.
3650 autoload - if set to "no" (any string beginning with 'n'),
3651 "bootp" will just load perform a lookup of the
3652 configuration from the BOOTP server, but not try to
3653 load any image using TFTP
3655 autostart - if set to "yes", an image loaded using the "bootp",
3656 "rarpboot", "tftpboot" or "diskboot" commands will
3657 be automatically started (by internally calling
3658 "bootm")
3660 If set to "no", a standalone image passed to the
3661 "bootm" command will be copied to the load address
3662 (and eventually uncompressed), but NOT be started.
3663 This can be used to load and uncompress arbitrary
3664 data.
3666 fdt_high - if set this restricts the maximum address that the
3667 flattened device tree will be copied into upon boot.
3668 For example, if you have a system with 1 GB memory
3669 at physical address 0x10000000, while Linux kernel
3670 only recognizes the first 704 MB as low memory, you
3671 may need to set fdt_high as 0x3C000000 to have the
3672 device tree blob be copied to the maximum address
3673 of the 704 MB low memory, so that Linux kernel can
3674 access it during the boot procedure.
3676 If this is set to the special value 0xFFFFFFFF then
3677 the fdt will not be copied at all on boot. For this
3678 to work it must reside in writable memory, have
3679 sufficient padding on the end of it for u-boot to
3680 add the information it needs into it, and the memory
3681 must be accessible by the kernel.
3683 fdtcontroladdr- if set this is the address of the control flattened
3684 device tree used by U-Boot when CONFIG_OF_CONTROL is
3685 defined.
3687 i2cfast - (PPC405GP|PPC405EP only)
3688 if set to 'y' configures Linux I2C driver for fast
3689 mode (400kHZ). This environment variable is used in
3690 initialization code. So, for changes to be effective
3691 it must be saved and board must be reset.
3693 initrd_high - restrict positioning of initrd images:
3694 If this variable is not set, initrd images will be
3695 copied to the highest possible address in RAM; this
3696 is usually what you want since it allows for
3697 maximum initrd size. If for some reason you want to
3698 make sure that the initrd image is loaded below the
3699 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
3700 variable to a value of "no" or "off" or "0".
3701 Alternatively, you can set it to a maximum upper
3702 address to use (U-Boot will still check that it
3703 does not overwrite the U-Boot stack and data).
3705 For instance, when you have a system with 16 MB
3706 RAM, and want to reserve 4 MB from use by Linux,
3707 you can do this by adding "mem=12M" to the value of
3708 the "bootargs" variable. However, now you must make
3709 sure that the initrd image is placed in the first
3710 12 MB as well - this can be done with
3712 setenv initrd_high 00c00000
3714 If you set initrd_high to 0xFFFFFFFF, this is an
3715 indication to U-Boot that all addresses are legal
3716 for the Linux kernel, including addresses in flash
3717 memory. In this case U-Boot will NOT COPY the
3718 ramdisk at all. This may be useful to reduce the
3719 boot time on your system, but requires that this
3720 feature is supported by your Linux kernel.
3722 ipaddr - IP address; needed for tftpboot command
3724 loadaddr - Default load address for commands like "bootp",
3725 "rarpboot", "tftpboot", "loadb" or "diskboot"
3727 loads_echo - see CONFIG_LOADS_ECHO
3729 serverip - TFTP server IP address; needed for tftpboot command
3731 bootretry - see CONFIG_BOOT_RETRY_TIME
3733 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
3735 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
3737 ethprime - controls which interface is used first.
3739 ethact - controls which interface is currently active.
3740 For example you can do the following
3742 => setenv ethact FEC
3743 => ping 192.168.0.1 # traffic sent on FEC
3744 => setenv ethact SCC
3745 => ping 10.0.0.1 # traffic sent on SCC
3747 ethrotate - When set to "no" U-Boot does not go through all
3748 available network interfaces.
3749 It just stays at the currently selected interface.
3751 netretry - When set to "no" each network operation will
3752 either succeed or fail without retrying.
3753 When set to "once" the network operation will
3754 fail when all the available network interfaces
3755 are tried once without success.
3756 Useful on scripts which control the retry operation
3757 themselves.
3759 npe_ucode - set load address for the NPE microcode
3761 tftpsrcport - If this is set, the value is used for TFTP's
3762 UDP source port.
3764 tftpdstport - If this is set, the value is used for TFTP's UDP
3765 destination port instead of the Well Know Port 69.
3767 tftpblocksize - Block size to use for TFTP transfers; if not set,
3768 we use the TFTP server's default block size
3770 tftptimeout - Retransmission timeout for TFTP packets (in milli-
3771 seconds, minimum value is 1000 = 1 second). Defines
3772 when a packet is considered to be lost so it has to
3773 be retransmitted. The default is 5000 = 5 seconds.
3774 Lowering this value may make downloads succeed
3775 faster in networks with high packet loss rates or
3776 with unreliable TFTP servers.
3778 vlan - When set to a value < 4095 the traffic over
3779 Ethernet is encapsulated/received over 802.1q
3780 VLAN tagged frames.
3782 The following image location variables contain the location of images
3783 used in booting. The "Image" column gives the role of the image and is
3784 not an environment variable name. The other columns are environment
3785 variable names. "File Name" gives the name of the file on a TFTP
3786 server, "RAM Address" gives the location in RAM the image will be
3787 loaded to, and "Flash Location" gives the image's address in NOR
3788 flash or offset in NAND flash.
3790 *Note* - these variables don't have to be defined for all boards, some
3791 boards currenlty use other variables for these purposes, and some
3792 boards use these variables for other purposes.
3794 Image File Name RAM Address Flash Location
3795 ----- --------- ----------- --------------
3796 u-boot u-boot u-boot_addr_r u-boot_addr
3797 Linux kernel bootfile kernel_addr_r kernel_addr
3798 device tree blob fdtfile fdt_addr_r fdt_addr
3799 ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
3801 The following environment variables may be used and automatically
3802 updated by the network boot commands ("bootp" and "rarpboot"),
3803 depending the information provided by your boot server:
3805 bootfile - see above
3806 dnsip - IP address of your Domain Name Server
3807 dnsip2 - IP address of your secondary Domain Name Server
3808 gatewayip - IP address of the Gateway (Router) to use
3809 hostname - Target hostname
3810 ipaddr - see above
3811 netmask - Subnet Mask
3812 rootpath - Pathname of the root filesystem on the NFS server
3813 serverip - see above
3816 There are two special Environment Variables:
3818 serial# - contains hardware identification information such
3819 as type string and/or serial number
3820 ethaddr - Ethernet address
3822 These variables can be set only once (usually during manufacturing of
3823 the board). U-Boot refuses to delete or overwrite these variables
3824 once they have been set once.
3827 Further special Environment Variables:
3829 ver - Contains the U-Boot version string as printed
3830 with the "version" command. This variable is
3831 readonly (see CONFIG_VERSION_VARIABLE).
3834 Please note that changes to some configuration parameters may take
3835 only effect after the next boot (yes, that's just like Windoze :-).
3838 Command Line Parsing:
3839 =====================
3841 There are two different command line parsers available with U-Boot:
3842 the old "simple" one, and the much more powerful "hush" shell:
3844 Old, simple command line parser:
3845 --------------------------------
3847 - supports environment variables (through setenv / saveenv commands)
3848 - several commands on one line, separated by ';'
3849 - variable substitution using "... ${name} ..." syntax
3850 - special characters ('$', ';') can be escaped by prefixing with '\',
3851 for example:
3852 setenv bootcmd bootm \${address}
3853 - You can also escape text by enclosing in single apostrophes, for example:
3854 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
3856 Hush shell:
3857 -----------
3859 - similar to Bourne shell, with control structures like
3860 if...then...else...fi, for...do...done; while...do...done,
3861 until...do...done, ...
3862 - supports environment ("global") variables (through setenv / saveenv
3863 commands) and local shell variables (through standard shell syntax
3864 "name=value"); only environment variables can be used with "run"
3865 command
3867 General rules:
3868 --------------
3870 (1) If a command line (or an environment variable executed by a "run"
3871 command) contains several commands separated by semicolon, and
3872 one of these commands fails, then the remaining commands will be
3873 executed anyway.
3875 (2) If you execute several variables with one call to run (i. e.
3876 calling run with a list of variables as arguments), any failing
3877 command will cause "run" to terminate, i. e. the remaining
3878 variables are not executed.
3880 Note for Redundant Ethernet Interfaces:
3881 =======================================
3883 Some boards come with redundant Ethernet interfaces; U-Boot supports
3884 such configurations and is capable of automatic selection of a
3885 "working" interface when needed. MAC assignment works as follows:
3887 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
3888 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
3889 "eth1addr" (=>eth1), "eth2addr", ...
3891 If the network interface stores some valid MAC address (for instance
3892 in SROM), this is used as default address if there is NO correspon-
3893 ding setting in the environment; if the corresponding environment
3894 variable is set, this overrides the settings in the card; that means:
3896 o If the SROM has a valid MAC address, and there is no address in the
3897 environment, the SROM's address is used.
3899 o If there is no valid address in the SROM, and a definition in the
3900 environment exists, then the value from the environment variable is
3901 used.
3903 o If both the SROM and the environment contain a MAC address, and
3904 both addresses are the same, this MAC address is used.
3906 o If both the SROM and the environment contain a MAC address, and the
3907 addresses differ, the value from the environment is used and a
3908 warning is printed.
3910 o If neither SROM nor the environment contain a MAC address, an error
3911 is raised.
3913 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
3914 will be programmed into hardware as part of the initialization process. This
3915 may be skipped by setting the appropriate 'ethmacskip' environment variable.
3916 The naming convention is as follows:
3917 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
3919 Image Formats:
3920 ==============
3922 U-Boot is capable of booting (and performing other auxiliary operations on)
3923 images in two formats:
3925 New uImage format (FIT)
3926 -----------------------
3928 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
3929 to Flattened Device Tree). It allows the use of images with multiple
3930 components (several kernels, ramdisks, etc.), with contents protected by
3931 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
3934 Old uImage format
3935 -----------------
3937 Old image format is based on binary files which can be basically anything,
3938 preceded by a special header; see the definitions in include/image.h for
3939 details; basically, the header defines the following image properties:
3941 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
3942 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
3943 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
3944 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
3945 INTEGRITY).
3946 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
3947 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
3948 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC).
3949 * Compression Type (uncompressed, gzip, bzip2)
3950 * Load Address
3951 * Entry Point
3952 * Image Name
3953 * Image Timestamp
3955 The header is marked by a special Magic Number, and both the header
3956 and the data portions of the image are secured against corruption by
3957 CRC32 checksums.
3960 Linux Support:
3961 ==============
3963 Although U-Boot should support any OS or standalone application
3964 easily, the main focus has always been on Linux during the design of
3965 U-Boot.
3967 U-Boot includes many features that so far have been part of some
3968 special "boot loader" code within the Linux kernel. Also, any
3969 "initrd" images to be used are no longer part of one big Linux image;
3970 instead, kernel and "initrd" are separate images. This implementation
3971 serves several purposes:
3973 - the same features can be used for other OS or standalone
3974 applications (for instance: using compressed images to reduce the
3975 Flash memory footprint)
3977 - it becomes much easier to port new Linux kernel versions because
3978 lots of low-level, hardware dependent stuff are done by U-Boot
3980 - the same Linux kernel image can now be used with different "initrd"
3981 images; of course this also means that different kernel images can
3982 be run with the same "initrd". This makes testing easier (you don't
3983 have to build a new "zImage.initrd" Linux image when you just
3984 change a file in your "initrd"). Also, a field-upgrade of the
3985 software is easier now.
3988 Linux HOWTO:
3989 ============
3991 Porting Linux to U-Boot based systems:
3992 ---------------------------------------
3994 U-Boot cannot save you from doing all the necessary modifications to
3995 configure the Linux device drivers for use with your target hardware
3996 (no, we don't intend to provide a full virtual machine interface to
3997 Linux :-).
3999 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
4001 Just make sure your machine specific header file (for instance
4002 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
4003 Information structure as we define in include/asm-<arch>/u-boot.h,
4004 and make sure that your definition of IMAP_ADDR uses the same value
4005 as your U-Boot configuration in CONFIG_SYS_IMMR.
4008 Configuring the Linux kernel:
4009 -----------------------------
4011 No specific requirements for U-Boot. Make sure you have some root
4012 device (initial ramdisk, NFS) for your target system.
4015 Building a Linux Image:
4016 -----------------------
4018 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
4019 not used. If you use recent kernel source, a new build target
4020 "uImage" will exist which automatically builds an image usable by
4021 U-Boot. Most older kernels also have support for a "pImage" target,
4022 which was introduced for our predecessor project PPCBoot and uses a
4023 100% compatible format.
4025 Example:
4027 make TQM850L_config
4028 make oldconfig
4029 make dep
4030 make uImage
4032 The "uImage" build target uses a special tool (in 'tools/mkimage') to
4033 encapsulate a compressed Linux kernel image with header information,
4034 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
4036 * build a standard "vmlinux" kernel image (in ELF binary format):
4038 * convert the kernel into a raw binary image:
4040 ${CROSS_COMPILE}-objcopy -O binary \
4041 -R .note -R .comment \
4042 -S vmlinux linux.bin
4044 * compress the binary image:
4046 gzip -9 linux.bin
4048 * package compressed binary image for U-Boot:
4050 mkimage -A ppc -O linux -T kernel -C gzip \
4051 -a 0 -e 0 -n "Linux Kernel Image" \
4052 -d linux.bin.gz uImage
4055 The "mkimage" tool can also be used to create ramdisk images for use
4056 with U-Boot, either separated from the Linux kernel image, or
4057 combined into one file. "mkimage" encapsulates the images with a 64
4058 byte header containing information about target architecture,
4059 operating system, image type, compression method, entry points, time
4060 stamp, CRC32 checksums, etc.
4062 "mkimage" can be called in two ways: to verify existing images and
4063 print the header information, or to build new images.
4065 In the first form (with "-l" option) mkimage lists the information
4066 contained in the header of an existing U-Boot image; this includes
4067 checksum verification:
4069 tools/mkimage -l image
4070 -l ==> list image header information
4072 The second form (with "-d" option) is used to build a U-Boot image
4073 from a "data file" which is used as image payload:
4075 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
4076 -n name -d data_file image
4077 -A ==> set architecture to 'arch'
4078 -O ==> set operating system to 'os'
4079 -T ==> set image type to 'type'
4080 -C ==> set compression type 'comp'
4081 -a ==> set load address to 'addr' (hex)
4082 -e ==> set entry point to 'ep' (hex)
4083 -n ==> set image name to 'name'
4084 -d ==> use image data from 'datafile'
4086 Right now, all Linux kernels for PowerPC systems use the same load
4087 address (0x00000000), but the entry point address depends on the
4088 kernel version:
4090 - 2.2.x kernels have the entry point at 0x0000000C,
4091 - 2.3.x and later kernels have the entry point at 0x00000000.
4093 So a typical call to build a U-Boot image would read:
4095 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
4096 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
4097 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
4098 > examples/uImage.TQM850L
4099 Image Name: 2.4.4 kernel for TQM850L
4100 Created: Wed Jul 19 02:34:59 2000
4101 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4102 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
4103 Load Address: 0x00000000
4104 Entry Point: 0x00000000
4106 To verify the contents of the image (or check for corruption):
4108 -> tools/mkimage -l examples/uImage.TQM850L
4109 Image Name: 2.4.4 kernel for TQM850L
4110 Created: Wed Jul 19 02:34:59 2000
4111 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4112 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
4113 Load Address: 0x00000000
4114 Entry Point: 0x00000000
4116 NOTE: for embedded systems where boot time is critical you can trade
4117 speed for memory and install an UNCOMPRESSED image instead: this
4118 needs more space in Flash, but boots much faster since it does not
4119 need to be uncompressed:
4121 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
4122 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
4123 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
4124 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
4125 > examples/uImage.TQM850L-uncompressed
4126 Image Name: 2.4.4 kernel for TQM850L
4127 Created: Wed Jul 19 02:34:59 2000
4128 Image Type: PowerPC Linux Kernel Image (uncompressed)
4129 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
4130 Load Address: 0x00000000
4131 Entry Point: 0x00000000
4134 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
4135 when your kernel is intended to use an initial ramdisk:
4137 -> tools/mkimage -n 'Simple Ramdisk Image' \
4138 > -A ppc -O linux -T ramdisk -C gzip \
4139 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
4140 Image Name: Simple Ramdisk Image
4141 Created: Wed Jan 12 14:01:50 2000
4142 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4143 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
4144 Load Address: 0x00000000
4145 Entry Point: 0x00000000
4148 Installing a Linux Image:
4149 -------------------------
4151 To downloading a U-Boot image over the serial (console) interface,
4152 you must convert the image to S-Record format:
4154 objcopy -I binary -O srec examples/image examples/image.srec
4156 The 'objcopy' does not understand the information in the U-Boot
4157 image header, so the resulting S-Record file will be relative to
4158 address 0x00000000. To load it to a given address, you need to
4159 specify the target address as 'offset' parameter with the 'loads'
4160 command.
4162 Example: install the image to address 0x40100000 (which on the
4163 TQM8xxL is in the first Flash bank):
4165 => erase 40100000 401FFFFF
4167 .......... done
4168 Erased 8 sectors
4170 => loads 40100000
4171 ## Ready for S-Record download ...
4172 ~>examples/image.srec
4173 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
4174 ...
4175 15989 15990 15991 15992
4176 [file transfer complete]
4177 [connected]
4178 ## Start Addr = 0x00000000
4181 You can check the success of the download using the 'iminfo' command;
4182 this includes a checksum verification so you can be sure no data
4183 corruption happened:
4185 => imi 40100000
4187 ## Checking Image at 40100000 ...
4188 Image Name: 2.2.13 for initrd on TQM850L
4189 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4190 Data Size: 335725 Bytes = 327 kB = 0 MB
4191 Load Address: 00000000
4192 Entry Point: 0000000c
4193 Verifying Checksum ... OK
4196 Boot Linux:
4197 -----------
4199 The "bootm" command is used to boot an application that is stored in
4200 memory (RAM or Flash). In case of a Linux kernel image, the contents
4201 of the "bootargs" environment variable is passed to the kernel as
4202 parameters. You can check and modify this variable using the
4203 "printenv" and "setenv" commands:
4206 => printenv bootargs
4207 bootargs=root=/dev/ram
4209 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4211 => printenv bootargs
4212 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4214 => bootm 40020000
4215 ## Booting Linux kernel at 40020000 ...
4216 Image Name: 2.2.13 for NFS on TQM850L
4217 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4218 Data Size: 381681 Bytes = 372 kB = 0 MB
4219 Load Address: 00000000
4220 Entry Point: 0000000c
4221 Verifying Checksum ... OK
4222 Uncompressing Kernel Image ... OK
4223 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
4224 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4225 time_init: decrementer frequency = 187500000/60
4226 Calibrating delay loop... 49.77 BogoMIPS
4227 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
4228 ...
4230 If you want to boot a Linux kernel with initial RAM disk, you pass
4231 the memory addresses of both the kernel and the initrd image (PPBCOOT
4232 format!) to the "bootm" command:
4234 => imi 40100000 40200000
4236 ## Checking Image at 40100000 ...
4237 Image Name: 2.2.13 for initrd on TQM850L
4238 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4239 Data Size: 335725 Bytes = 327 kB = 0 MB
4240 Load Address: 00000000
4241 Entry Point: 0000000c
4242 Verifying Checksum ... OK
4244 ## Checking Image at 40200000 ...
4245 Image Name: Simple Ramdisk Image
4246 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4247 Data Size: 566530 Bytes = 553 kB = 0 MB
4248 Load Address: 00000000
4249 Entry Point: 00000000
4250 Verifying Checksum ... OK
4252 => bootm 40100000 40200000
4253 ## Booting Linux kernel at 40100000 ...
4254 Image Name: 2.2.13 for initrd on TQM850L
4255 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4256 Data Size: 335725 Bytes = 327 kB = 0 MB
4257 Load Address: 00000000
4258 Entry Point: 0000000c
4259 Verifying Checksum ... OK
4260 Uncompressing Kernel Image ... OK
4261 ## Loading RAMDisk Image at 40200000 ...
4262 Image Name: Simple Ramdisk Image
4263 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4264 Data Size: 566530 Bytes = 553 kB = 0 MB
4265 Load Address: 00000000
4266 Entry Point: 00000000
4267 Verifying Checksum ... OK
4268 Loading Ramdisk ... OK
4269 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
4270 Boot arguments: root=/dev/ram
4271 time_init: decrementer frequency = 187500000/60
4272 Calibrating delay loop... 49.77 BogoMIPS
4273 ...
4274 RAMDISK: Compressed image found at block 0
4275 VFS: Mounted root (ext2 filesystem).
4277 bash#
4279 Boot Linux and pass a flat device tree:
4280 -----------
4282 First, U-Boot must be compiled with the appropriate defines. See the section
4283 titled "Linux Kernel Interface" above for a more in depth explanation. The
4284 following is an example of how to start a kernel and pass an updated
4285 flat device tree:
4287 => print oftaddr
4288 oftaddr=0x300000
4289 => print oft
4290 oft=oftrees/mpc8540ads.dtb
4291 => tftp $oftaddr $oft
4292 Speed: 1000, full duplex
4293 Using TSEC0 device
4294 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
4295 Filename 'oftrees/mpc8540ads.dtb'.
4296 Load address: 0x300000
4297 Loading: #
4298 done
4299 Bytes transferred = 4106 (100a hex)
4300 => tftp $loadaddr $bootfile
4301 Speed: 1000, full duplex
4302 Using TSEC0 device
4303 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
4304 Filename 'uImage'.
4305 Load address: 0x200000
4306 Loading:############
4307 done
4308 Bytes transferred = 1029407 (fb51f hex)
4309 => print loadaddr
4310 loadaddr=200000
4311 => print oftaddr
4312 oftaddr=0x300000
4313 => bootm $loadaddr - $oftaddr
4314 ## Booting image at 00200000 ...
4315 Image Name: Linux-2.6.17-dirty
4316 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4317 Data Size: 1029343 Bytes = 1005.2 kB
4318 Load Address: 00000000
4319 Entry Point: 00000000
4320 Verifying Checksum ... OK
4321 Uncompressing Kernel Image ... OK
4322 Booting using flat device tree at 0x300000
4323 Using MPC85xx ADS machine description
4324 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
4325 [snip]
4328 More About U-Boot Image Types:
4329 ------------------------------
4331 U-Boot supports the following image types:
4333 "Standalone Programs" are directly runnable in the environment
4334 provided by U-Boot; it is expected that (if they behave
4335 well) you can continue to work in U-Boot after return from
4336 the Standalone Program.
4337 "OS Kernel Images" are usually images of some Embedded OS which
4338 will take over control completely. Usually these programs
4339 will install their own set of exception handlers, device
4340 drivers, set up the MMU, etc. - this means, that you cannot
4341 expect to re-enter U-Boot except by resetting the CPU.
4342 "RAMDisk Images" are more or less just data blocks, and their
4343 parameters (address, size) are passed to an OS kernel that is
4344 being started.
4345 "Multi-File Images" contain several images, typically an OS
4346 (Linux) kernel image and one or more data images like
4347 RAMDisks. This construct is useful for instance when you want
4348 to boot over the network using BOOTP etc., where the boot
4349 server provides just a single image file, but you want to get
4350 for instance an OS kernel and a RAMDisk image.
4352 "Multi-File Images" start with a list of image sizes, each
4353 image size (in bytes) specified by an "uint32_t" in network
4354 byte order. This list is terminated by an "(uint32_t)0".
4355 Immediately after the terminating 0 follow the images, one by
4356 one, all aligned on "uint32_t" boundaries (size rounded up to
4357 a multiple of 4 bytes).
4359 "Firmware Images" are binary images containing firmware (like
4360 U-Boot or FPGA images) which usually will be programmed to
4361 flash memory.
4363 "Script files" are command sequences that will be executed by
4364 U-Boot's command interpreter; this feature is especially
4365 useful when you configure U-Boot to use a real shell (hush)
4366 as command interpreter.
4369 Standalone HOWTO:
4370 =================
4372 One of the features of U-Boot is that you can dynamically load and
4373 run "standalone" applications, which can use some resources of
4374 U-Boot like console I/O functions or interrupt services.
4376 Two simple examples are included with the sources:
4378 "Hello World" Demo:
4379 -------------------
4381 'examples/hello_world.c' contains a small "Hello World" Demo
4382 application; it is automatically compiled when you build U-Boot.
4383 It's configured to run at address 0x00040004, so you can play with it
4384 like that:
4386 => loads
4387 ## Ready for S-Record download ...
4388 ~>examples/hello_world.srec
4389 1 2 3 4 5 6 7 8 9 10 11 ...
4390 [file transfer complete]
4391 [connected]
4392 ## Start Addr = 0x00040004
4394 => go 40004 Hello World! This is a test.
4395 ## Starting application at 0x00040004 ...
4396 Hello World
4397 argc = 7
4398 argv[0] = "40004"
4399 argv[1] = "Hello"
4400 argv[2] = "World!"
4401 argv[3] = "This"
4402 argv[4] = "is"
4403 argv[5] = "a"
4404 argv[6] = "test."
4405 argv[7] = "<NULL>"
4406 Hit any key to exit ...
4408 ## Application terminated, rc = 0x0
4410 Another example, which demonstrates how to register a CPM interrupt
4411 handler with the U-Boot code, can be found in 'examples/timer.c'.
4412 Here, a CPM timer is set up to generate an interrupt every second.
4413 The interrupt service routine is trivial, just printing a '.'
4414 character, but this is just a demo program. The application can be
4415 controlled by the following keys:
4417 ? - print current values og the CPM Timer registers
4418 b - enable interrupts and start timer
4419 e - stop timer and disable interrupts
4420 q - quit application
4422 => loads
4423 ## Ready for S-Record download ...
4424 ~>examples/timer.srec
4425 1 2 3 4 5 6 7 8 9 10 11 ...
4426 [file transfer complete]
4427 [connected]
4428 ## Start Addr = 0x00040004
4430 => go 40004
4431 ## Starting application at 0x00040004 ...
4432 TIMERS=0xfff00980
4433 Using timer 1
4434 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
4436 Hit 'b':
4437 [q, b, e, ?] Set interval 1000000 us
4438 Enabling timer
4439 Hit '?':
4440 [q, b, e, ?] ........
4441 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
4442 Hit '?':
4443 [q, b, e, ?] .
4444 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
4445 Hit '?':
4446 [q, b, e, ?] .
4447 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
4448 Hit '?':
4449 [q, b, e, ?] .
4450 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
4451 Hit 'e':
4452 [q, b, e, ?] ...Stopping timer
4453 Hit 'q':
4454 [q, b, e, ?] ## Application terminated, rc = 0x0
4457 Minicom warning:
4458 ================
4460 Over time, many people have reported problems when trying to use the
4461 "minicom" terminal emulation program for serial download. I (wd)
4462 consider minicom to be broken, and recommend not to use it. Under
4463 Unix, I recommend to use C-Kermit for general purpose use (and
4464 especially for kermit binary protocol download ("loadb" command), and
4465 use "cu" for S-Record download ("loads" command).
4467 Nevertheless, if you absolutely want to use it try adding this
4468 configuration to your "File transfer protocols" section:
4470 Name Program Name U/D FullScr IO-Red. Multi
4471 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
4472 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
4475 NetBSD Notes:
4476 =============
4478 Starting at version 0.9.2, U-Boot supports NetBSD both as host
4479 (build U-Boot) and target system (boots NetBSD/mpc8xx).
4481 Building requires a cross environment; it is known to work on
4482 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
4483 need gmake since the Makefiles are not compatible with BSD make).
4484 Note that the cross-powerpc package does not install include files;
4485 attempting to build U-Boot will fail because <machine/ansi.h> is
4486 missing. This file has to be installed and patched manually:
4488 # cd /usr/pkg/cross/powerpc-netbsd/include
4489 # mkdir powerpc
4490 # ln -s powerpc machine
4491 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
4492 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
4494 Native builds *don't* work due to incompatibilities between native
4495 and U-Boot include files.
4497 Booting assumes that (the first part of) the image booted is a
4498 stage-2 loader which in turn loads and then invokes the kernel
4499 proper. Loader sources will eventually appear in the NetBSD source
4500 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
4501 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
4504 Implementation Internals:
4505 =========================
4507 The following is not intended to be a complete description of every
4508 implementation detail. However, it should help to understand the
4509 inner workings of U-Boot and make it easier to port it to custom
4510 hardware.
4513 Initial Stack, Global Data:
4514 ---------------------------
4516 The implementation of U-Boot is complicated by the fact that U-Boot
4517 starts running out of ROM (flash memory), usually without access to
4518 system RAM (because the memory controller is not initialized yet).
4519 This means that we don't have writable Data or BSS segments, and BSS
4520 is not initialized as zero. To be able to get a C environment working
4521 at all, we have to allocate at least a minimal stack. Implementation
4522 options for this are defined and restricted by the CPU used: Some CPU
4523 models provide on-chip memory (like the IMMR area on MPC8xx and
4524 MPC826x processors), on others (parts of) the data cache can be
4525 locked as (mis-) used as memory, etc.
4527 Chris Hallinan posted a good summary of these issues to the
4528 U-Boot mailing list:
4530 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
4531 From: "Chris Hallinan" <clh@net1plus.com>
4532 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
4533 ...
4535 Correct me if I'm wrong, folks, but the way I understand it
4536 is this: Using DCACHE as initial RAM for Stack, etc, does not
4537 require any physical RAM backing up the cache. The cleverness
4538 is that the cache is being used as a temporary supply of
4539 necessary storage before the SDRAM controller is setup. It's
4540 beyond the scope of this list to explain the details, but you
4541 can see how this works by studying the cache architecture and
4542 operation in the architecture and processor-specific manuals.
4544 OCM is On Chip Memory, which I believe the 405GP has 4K. It
4545 is another option for the system designer to use as an
4546 initial stack/RAM area prior to SDRAM being available. Either
4547 option should work for you. Using CS 4 should be fine if your
4548 board designers haven't used it for something that would
4549 cause you grief during the initial boot! It is frequently not
4550 used.
4552 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
4553 with your processor/board/system design. The default value
4554 you will find in any recent u-boot distribution in
4555 walnut.h should work for you. I'd set it to a value larger
4556 than your SDRAM module. If you have a 64MB SDRAM module, set
4557 it above 400_0000. Just make sure your board has no resources
4558 that are supposed to respond to that address! That code in
4559 start.S has been around a while and should work as is when
4560 you get the config right.
4562 -Chris Hallinan
4563 DS4.COM, Inc.
4565 It is essential to remember this, since it has some impact on the C
4566 code for the initialization procedures:
4568 * Initialized global data (data segment) is read-only. Do not attempt
4569 to write it.
4571 * Do not use any uninitialized global data (or implicitely initialized
4572 as zero data - BSS segment) at all - this is undefined, initiali-
4573 zation is performed later (when relocating to RAM).
4575 * Stack space is very limited. Avoid big data buffers or things like
4576 that.
4578 Having only the stack as writable memory limits means we cannot use
4579 normal global data to share information beween the code. But it
4580 turned out that the implementation of U-Boot can be greatly
4581 simplified by making a global data structure (gd_t) available to all
4582 functions. We could pass a pointer to this data as argument to _all_
4583 functions, but this would bloat the code. Instead we use a feature of
4584 the GCC compiler (Global Register Variables) to share the data: we
4585 place a pointer (gd) to the global data into a register which we
4586 reserve for this purpose.
4588 When choosing a register for such a purpose we are restricted by the
4589 relevant (E)ABI specifications for the current architecture, and by
4590 GCC's implementation.
4592 For PowerPC, the following registers have specific use:
4593 R1: stack pointer
4594 R2: reserved for system use
4595 R3-R4: parameter passing and return values
4596 R5-R10: parameter passing
4597 R13: small data area pointer
4598 R30: GOT pointer
4599 R31: frame pointer
4601 (U-Boot also uses R12 as internal GOT pointer. r12
4602 is a volatile register so r12 needs to be reset when
4603 going back and forth between asm and C)
4605 ==> U-Boot will use R2 to hold a pointer to the global data
4607 Note: on PPC, we could use a static initializer (since the
4608 address of the global data structure is known at compile time),
4609 but it turned out that reserving a register results in somewhat
4610 smaller code - although the code savings are not that big (on
4611 average for all boards 752 bytes for the whole U-Boot image,
4612 624 text + 127 data).
4614 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
4615 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
4617 ==> U-Boot will use P3 to hold a pointer to the global data
4619 On ARM, the following registers are used:
4621 R0: function argument word/integer result
4622 R1-R3: function argument word
4623 R9: GOT pointer
4624 R10: stack limit (used only if stack checking if enabled)
4625 R11: argument (frame) pointer
4626 R12: temporary workspace
4627 R13: stack pointer
4628 R14: link register
4629 R15: program counter
4631 ==> U-Boot will use R8 to hold a pointer to the global data
4633 On Nios II, the ABI is documented here:
4634 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
4636 ==> U-Boot will use gp to hold a pointer to the global data
4638 Note: on Nios II, we give "-G0" option to gcc and don't use gp
4639 to access small data sections, so gp is free.
4641 On NDS32, the following registers are used:
4643 R0-R1: argument/return
4644 R2-R5: argument
4645 R15: temporary register for assembler
4646 R16: trampoline register
4647 R28: frame pointer (FP)
4648 R29: global pointer (GP)
4649 R30: link register (LP)
4650 R31: stack pointer (SP)
4651 PC: program counter (PC)
4653 ==> U-Boot will use R10 to hold a pointer to the global data
4655 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
4656 or current versions of GCC may "optimize" the code too much.
4658 Memory Management:
4659 ------------------
4661 U-Boot runs in system state and uses physical addresses, i.e. the
4662 MMU is not used either for address mapping nor for memory protection.
4664 The available memory is mapped to fixed addresses using the memory
4665 controller. In this process, a contiguous block is formed for each
4666 memory type (Flash, SDRAM, SRAM), even when it consists of several
4667 physical memory banks.
4669 U-Boot is installed in the first 128 kB of the first Flash bank (on
4670 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
4671 booting and sizing and initializing DRAM, the code relocates itself
4672 to the upper end of DRAM. Immediately below the U-Boot code some
4673 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
4674 configuration setting]. Below that, a structure with global Board
4675 Info data is placed, followed by the stack (growing downward).
4677 Additionally, some exception handler code is copied to the low 8 kB
4678 of DRAM (0x00000000 ... 0x00001FFF).
4680 So a typical memory configuration with 16 MB of DRAM could look like
4681 this:
4683 0x0000 0000 Exception Vector code
4684 :
4685 0x0000 1FFF
4686 0x0000 2000 Free for Application Use
4687 :
4688 :
4690 :
4691 :
4692 0x00FB FF20 Monitor Stack (Growing downward)
4693 0x00FB FFAC Board Info Data and permanent copy of global data
4694 0x00FC 0000 Malloc Arena
4695 :
4696 0x00FD FFFF
4697 0x00FE 0000 RAM Copy of Monitor Code
4698 ... eventually: LCD or video framebuffer
4699 ... eventually: pRAM (Protected RAM - unchanged by reset)
4700 0x00FF FFFF [End of RAM]
4703 System Initialization:
4704 ----------------------
4706 In the reset configuration, U-Boot starts at the reset entry point
4707 (on most PowerPC systems at address 0x00000100). Because of the reset
4708 configuration for CS0# this is a mirror of the onboard Flash memory.
4709 To be able to re-map memory U-Boot then jumps to its link address.
4710 To be able to implement the initialization code in C, a (small!)
4711 initial stack is set up in the internal Dual Ported RAM (in case CPUs
4712 which provide such a feature like MPC8xx or MPC8260), or in a locked
4713 part of the data cache. After that, U-Boot initializes the CPU core,
4714 the caches and the SIU.
4716 Next, all (potentially) available memory banks are mapped using a
4717 preliminary mapping. For example, we put them on 512 MB boundaries
4718 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
4719 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
4720 programmed for SDRAM access. Using the temporary configuration, a
4721 simple memory test is run that determines the size of the SDRAM
4722 banks.
4724 When there is more than one SDRAM bank, and the banks are of
4725 different size, the largest is mapped first. For equal size, the first
4726 bank (CS2#) is mapped first. The first mapping is always for address
4727 0x00000000, with any additional banks following immediately to create
4728 contiguous memory starting from 0.
4730 Then, the monitor installs itself at the upper end of the SDRAM area
4731 and allocates memory for use by malloc() and for the global Board
4732 Info data; also, the exception vector code is copied to the low RAM
4733 pages, and the final stack is set up.
4735 Only after this relocation will you have a "normal" C environment;
4736 until that you are restricted in several ways, mostly because you are
4737 running from ROM, and because the code will have to be relocated to a
4738 new address in RAM.
4741 U-Boot Porting Guide:
4742 ----------------------
4744 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
4745 list, October 2002]
4748 int main(int argc, char *argv[])
4749 {
4750 sighandler_t no_more_time;
4752 signal(SIGALRM, no_more_time);
4753 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
4755 if (available_money > available_manpower) {
4756 Pay consultant to port U-Boot;
4757 return 0;
4758 }
4760 Download latest U-Boot source;
4762 Subscribe to u-boot mailing list;
4764 if (clueless)
4765 email("Hi, I am new to U-Boot, how do I get started?");
4767 while (learning) {
4768 Read the README file in the top level directory;
4769 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
4770 Read applicable doc/*.README;
4771 Read the source, Luke;
4772 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
4773 }
4775 if (available_money > toLocalCurrency ($2500))
4776 Buy a BDI3000;
4777 else
4778 Add a lot of aggravation and time;
4780 if (a similar board exists) { /* hopefully... */
4781 cp -a board/<similar> board/<myboard>
4782 cp include/configs/<similar>.h include/configs/<myboard>.h
4783 } else {
4784 Create your own board support subdirectory;
4785 Create your own board include/configs/<myboard>.h file;
4786 }
4787 Edit new board/<myboard> files
4788 Edit new include/configs/<myboard>.h
4790 while (!accepted) {
4791 while (!running) {
4792 do {
4793 Add / modify source code;
4794 } until (compiles);
4795 Debug;
4796 if (clueless)
4797 email("Hi, I am having problems...");
4798 }
4799 Send patch file to the U-Boot email list;
4800 if (reasonable critiques)
4801 Incorporate improvements from email list code review;
4802 else
4803 Defend code as written;
4804 }
4806 return 0;
4807 }
4809 void no_more_time (int sig)
4810 {
4811 hire_a_guru();
4812 }
4815 Coding Standards:
4816 -----------------
4818 All contributions to U-Boot should conform to the Linux kernel
4819 coding style; see the file "Documentation/CodingStyle" and the script
4820 "scripts/Lindent" in your Linux kernel source directory.
4822 Source files originating from a different project (for example the
4823 MTD subsystem) are generally exempt from these guidelines and are not
4824 reformated to ease subsequent migration to newer versions of those
4825 sources.
4827 Please note that U-Boot is implemented in C (and to some small parts in
4828 Assembler); no C++ is used, so please do not use C++ style comments (//)
4829 in your code.
4831 Please also stick to the following formatting rules:
4832 - remove any trailing white space
4833 - use TAB characters for indentation and vertical alignment, not spaces
4834 - make sure NOT to use DOS '\r\n' line feeds
4835 - do not add more than 2 consecutive empty lines to source files
4836 - do not add trailing empty lines to source files
4838 Submissions which do not conform to the standards may be returned
4839 with a request to reformat the changes.
4842 Submitting Patches:
4843 -------------------
4845 Since the number of patches for U-Boot is growing, we need to
4846 establish some rules. Submissions which do not conform to these rules
4847 may be rejected, even when they contain important and valuable stuff.
4849 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
4851 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
4852 see http://lists.denx.de/mailman/listinfo/u-boot
4854 When you send a patch, please include the following information with
4855 it:
4857 * For bug fixes: a description of the bug and how your patch fixes
4858 this bug. Please try to include a way of demonstrating that the
4859 patch actually fixes something.
4861 * For new features: a description of the feature and your
4862 implementation.
4864 * A CHANGELOG entry as plaintext (separate from the patch)
4866 * For major contributions, your entry to the CREDITS file
4868 * When you add support for a new board, don't forget to add this
4869 board to the MAINTAINERS file, too.
4871 * If your patch adds new configuration options, don't forget to
4872 document these in the README file.
4874 * The patch itself. If you are using git (which is *strongly*
4875 recommended) you can easily generate the patch using the
4876 "git format-patch". If you then use "git send-email" to send it to
4877 the U-Boot mailing list, you will avoid most of the common problems
4878 with some other mail clients.
4880 If you cannot use git, use "diff -purN OLD NEW". If your version of
4881 diff does not support these options, then get the latest version of
4882 GNU diff.
4884 The current directory when running this command shall be the parent
4885 directory of the U-Boot source tree (i. e. please make sure that
4886 your patch includes sufficient directory information for the
4887 affected files).
4889 We prefer patches as plain text. MIME attachments are discouraged,
4890 and compressed attachments must not be used.
4892 * If one logical set of modifications affects or creates several
4893 files, all these changes shall be submitted in a SINGLE patch file.
4895 * Changesets that contain different, unrelated modifications shall be
4896 submitted as SEPARATE patches, one patch per changeset.
4899 Notes:
4901 * Before sending the patch, run the MAKEALL script on your patched
4902 source tree and make sure that no errors or warnings are reported
4903 for any of the boards.
4905 * Keep your modifications to the necessary minimum: A patch
4906 containing several unrelated changes or arbitrary reformats will be
4907 returned with a request to re-formatting / split it.
4909 * If you modify existing code, make sure that your new code does not
4910 add to the memory footprint of the code ;-) Small is beautiful!
4911 When adding new features, these should compile conditionally only
4912 (using #ifdef), and the resulting code with the new feature
4913 disabled must not need more memory than the old code without your
4914 modification.
4916 * Remember that there is a size limit of 100 kB per message on the
4917 u-boot mailing list. Bigger patches will be moderated. If they are
4918 reasonable and not too big, they will be acknowledged. But patches
4919 bigger than the size limit should be avoided.