1# 2# (C) Copyright 2000 - 2011 3# Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4# 5# See file CREDITS for list of people who contributed to this 6# project. 7# 8# This program is free software; you can redistribute it and/or 9# modify it under the terms of the GNU General Public License as 10# published by the Free Software Foundation; either version 2 of 11# the License, or (at your option) any later version. 12# 13# This program is distributed in the hope that it will be useful, 14# but WITHOUT ANY WARRANTY; without even the implied warranty of 15# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16# GNU General Public License for more details. 17# 18# You should have received a copy of the GNU General Public License 19# along with this program; if not, write to the Free Software 20# Foundation, Inc., 59 Temple Place, Suite 330, Boston, 21# MA 02111-1307 USA 22# 23 24Summary: 25======== 26 27This directory contains the source code for U-Boot, a boot loader for 28Embedded boards based on PowerPC, ARM, MIPS and several other 29processors, which can be installed in a boot ROM and used to 30initialize and test the hardware or to download and run application 31code. 32 33The development of U-Boot is closely related to Linux: some parts of 34the source code originate in the Linux source tree, we have some 35header files in common, and special provision has been made to 36support booting of Linux images. 37 38Some attention has been paid to make this software easily 39configurable and extendable. For instance, all monitor commands are 40implemented with the same call interface, so that it's very easy to 41add new commands. Also, instead of permanently adding rarely used 42code (for instance hardware test utilities) to the monitor, you can 43load and run it dynamically. 44 45 46Status: 47======= 48 49In general, all boards for which a configuration option exists in the 50Makefile have been tested to some extent and can be considered 51"working". In fact, many of them are used in production systems. 52 53In case of problems see the CHANGELOG and CREDITS files to find out 54who contributed the specific port. The MAINTAINERS file lists board 55maintainers. 56 57 58Where to get help: 59================== 60 61In case you have questions about, problems with or contributions for 62U-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 64on the mailing list - please search the archive before asking FAQ's. 65Please see http://lists.denx.de/pipermail/u-boot and 66http://dir.gmane.org/gmane.comp.boot-loaders.u-boot 67 68 69Where to get source code: 70========================= 71 72The U-Boot source code is maintained in the git repository at 73git://www.denx.de/git/u-boot.git ; you can browse it online at 74http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary 75 76The "snapshot" links on this page allow you to download tarballs of 77any version you might be interested in. Official releases are also 78available for FTP download from the ftp://ftp.denx.de/pub/u-boot/ 79directory. 80 81Pre-built (and tested) images are available from 82ftp://ftp.denx.de/pub/u-boot/images/ 83 84 85Where we come from: 86=================== 87 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 102 103 104Names and Spelling: 105=================== 106 107The "official" name of this project is "Das U-Boot". The spelling 108"U-Boot" shall be used in all written text (documentation, comments 109in source files etc.). Example: 110 111 This is the README file for the U-Boot project. 112 113File names etc. shall be based on the string "u-boot". Examples: 114 115 include/asm-ppc/u-boot.h 116 117 #include <asm/u-boot.h> 118 119Variable names, preprocessor constants etc. shall be either based on 120the string "u_boot" or on "U_BOOT". Example: 121 122 U_BOOT_VERSION u_boot_logo 123 IH_OS_U_BOOT u_boot_hush_start 124 125 126Versioning: 127=========== 128 129Starting with the release in October 2008, the names of the releases 130were changed from numerical release numbers without deeper meaning 131into a time stamp based numbering. Regular releases are identified by 132names consisting of the calendar year and month of the release date. 133Additional fields (if present) indicate release candidates or bug fix 134releases in "stable" maintenance trees. 135 136Examples: 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 140 141 142Directory Hierarchy: 143==================== 144 145/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. 233 234Software Configuration: 235======================= 236 237Configuration is usually done using C preprocessor defines; the 238rationale behind that is to avoid dead code whenever possible. 239 240There are two classes of configuration variables: 241 242* Configuration _OPTIONS_: 243 These are selectable by the user and have names beginning with 244 "CONFIG_". 245 246* 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_". 250 251Later we will add a configuration tool - probably similar to or even 252identical to what's used for the Linux kernel. Right now, we have to 253do the configuration by hand, which means creating some symbolic 254links and editing some configuration files. We use the TQM8xxL boards 255as an example here. 256 257 258Selection of Processor Architecture and Board Type: 259--------------------------------------------------- 260 261For all supported boards there are ready-to-use default 262configurations available; just type "make <board_name>_config". 263 264Example: For a TQM823L module type: 265 266 cd u-boot 267 make TQM823L_config 268 269For the Cogent platform, you need to specify the CPU type as well; 270e.g. "make cogent_mpc8xx_config". And also configure the cogent 271directory according to the instructions in cogent/README. 272 273 274Configuration Options: 275---------------------- 276 277Configuration depends on the combination of board and CPU type; all 278such information is kept in a configuration file 279"include/configs/<board_name>.h". 280 281Example: For a TQM823L module, all configuration settings are in 282"include/configs/TQM823L.h". 283 284 285Many of the options are named exactly as the corresponding Linux 286kernel configuration options. The intention is to make it easier to 287build a config tool - later. 288 289 290The following options need to be configured: 291 292- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 293 294- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 295 296- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 297 Define exactly one, e.g. CONFIG_ATSTK1002 298 299- 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_50 305 306- Motherboard Type: (if CONFIG_COGENT is defined) 307 Define exactly one of 308 CONFIG_CMA101, CONFIG_CMA102 309 310- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 311 Define one or more of 312 CONFIG_CMA302 313 314- 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" |\-/|\-/ 319 320- 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 327 328- 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 332 333- MPC824X Family Member (if CONFIG_MPC824X is defined) 334 Define exactly one of 335 CONFIG_MPC8240, CONFIG_MPC8245 336 337- 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) 344 345- 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 350 351 CONFIG_SYS_MEASURE_CPUCLK 352 353 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) 359 360 CONFIG_SYS_DELAYED_ICACHE 361 362 Define this option if you want to enable the 363 ICache only when Code runs from RAM. 364 365- 85xx CPU Options: 366 CONFIG_SYS_FSL_TBCLK_DIV 367 368 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. 371 372 CONFIG_SYS_FSL_PCIE_COMPAT 373 374 Defines the string to utilize when trying to match PCIe device 375 tree nodes for the given platform. 376 377- Intel Monahans options: 378 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO 379 380 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. 383 384 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO 385 386 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. 390 391- MIPS CPU options: 392 CONFIG_SYS_INIT_SP_OFFSET 393 394 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack 395 pointer. This is needed for the temporary stack before 396 relocation. 397 398 CONFIG_SYS_MIPS_CACHE_MODE 399 400 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 411 412 CONFIG_SYS_XWAY_EBU_BOOTCFG 413 414 Special option for Lantiq XWAY SoCs for booting from NOR flash. 415 See also arch/mips/cpu/mips32/start.S. 416 417 CONFIG_XWAY_SWAP_BYTES 418 419 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. 422 423- Linux Kernel Interface: 424 CONFIG_CLOCKS_IN_MHZ 425 426 U-Boot stores all clock information in Hz 427 internally. For binary compatibility with older Linux 428 kernels (which expect the clocks passed in the 429 bd_info data to be in MHz) the environment variable 430 "clocks_in_mhz" can be defined so that U-Boot 431 converts clock data to MHZ before passing it to the 432 Linux kernel. 433 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 434 "clocks_in_mhz=1" is automatically included in the 435 default environment. 436 437 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 438 439 When transferring memsize parameter to linux, some versions 440 expect it to be in bytes, others in MB. 441 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 442 443 CONFIG_OF_LIBFDT 444 445 New kernel versions are expecting firmware settings to be 446 passed using flattened device trees (based on open firmware 447 concepts). 448 449 CONFIG_OF_LIBFDT 450 * New libfdt-based support 451 * Adds the "fdt" command 452 * The bootm command automatically updates the fdt 453 454 OF_CPU - The proper name of the cpus node (only required for 455 MPC512X and MPC5xxx based boards). 456 OF_SOC - The proper name of the soc node (only required for 457 MPC512X and MPC5xxx based boards). 458 OF_TBCLK - The timebase frequency. 459 OF_STDOUT_PATH - The path to the console device 460 461 boards with QUICC Engines require OF_QE to set UCC MAC 462 addresses 463 464 CONFIG_OF_BOARD_SETUP 465 466 Board code has addition modification that it wants to make 467 to the flat device tree before handing it off to the kernel 468 469 CONFIG_OF_BOOT_CPU 470 471 This define fills in the correct boot CPU in the boot 472 param header, the default value is zero if undefined. 473 474 CONFIG_OF_IDE_FIXUP 475 476 U-Boot can detect if an IDE device is present or not. 477 If not, and this new config option is activated, U-Boot 478 removes the ATA node from the DTS before booting Linux, 479 so the Linux IDE driver does not probe the device and 480 crash. This is needed for buggy hardware (uc101) where 481 no pull down resistor is connected to the signal IDE5V_DD7. 482 483 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 484 485 This setting is mandatory for all boards that have only one 486 machine type and must be used to specify the machine type 487 number as it appears in the ARM machine registry 488 (see http://www.arm.linux.org.uk/developer/machines/). 489 Only boards that have multiple machine types supported 490 in a single configuration file and the machine type is 491 runtime discoverable, do not have to use this setting. 492 493- vxWorks boot parameters: 494 495 bootvx constructs a valid bootline using the following 496 environments variables: bootfile, ipaddr, serverip, hostname. 497 It loads the vxWorks image pointed bootfile. 498 499 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name 500 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address 501 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server 502 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters 503 504 CONFIG_SYS_VXWORKS_ADD_PARAMS 505 506 Add it at the end of the bootline. E.g "u=username pw=secret" 507 508 Note: If a "bootargs" environment is defined, it will overwride 509 the defaults discussed just above. 510 511- Cache Configuration: 512 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 513 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 514 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 515 516- Cache Configuration for ARM: 517 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 518 controller 519 CONFIG_SYS_PL310_BASE - Physical base address of PL310 520 controller register space 521 522- Serial Ports: 523 CONFIG_PL010_SERIAL 524 525 Define this if you want support for Amba PrimeCell PL010 UARTs. 526 527 CONFIG_PL011_SERIAL 528 529 Define this if you want support for Amba PrimeCell PL011 UARTs. 530 531 CONFIG_PL011_CLOCK 532 533 If you have Amba PrimeCell PL011 UARTs, set this variable to 534 the clock speed of the UARTs. 535 536 CONFIG_PL01x_PORTS 537 538 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 539 define this to a list of base addresses for each (supported) 540 port. See e.g. include/configs/versatile.h 541 542 CONFIG_PL011_SERIAL_RLCR 543 544 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500) 545 have separate receive and transmit line control registers. Set 546 this variable to initialize the extra register. 547 548 CONFIG_PL011_SERIAL_FLUSH_ON_INIT 549 550 On some platforms (e.g. U8500) U-Boot is loaded by a second stage 551 boot loader that has already initialized the UART. Define this 552 variable to flush the UART at init time. 553 554 555- Console Interface: 556 Depending on board, define exactly one serial port 557 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 558 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 559 console by defining CONFIG_8xx_CONS_NONE 560 561 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 562 port routines must be defined elsewhere 563 (i.e. serial_init(), serial_getc(), ...) 564 565 CONFIG_CFB_CONSOLE 566 Enables console device for a color framebuffer. Needs following 567 defines (cf. smiLynxEM, i8042) 568 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 569 (default big endian) 570 VIDEO_HW_RECTFILL graphic chip supports 571 rectangle fill 572 (cf. smiLynxEM) 573 VIDEO_HW_BITBLT graphic chip supports 574 bit-blit (cf. smiLynxEM) 575 VIDEO_VISIBLE_COLS visible pixel columns 576 (cols=pitch) 577 VIDEO_VISIBLE_ROWS visible pixel rows 578 VIDEO_PIXEL_SIZE bytes per pixel 579 VIDEO_DATA_FORMAT graphic data format 580 (0-5, cf. cfb_console.c) 581 VIDEO_FB_ADRS framebuffer address 582 VIDEO_KBD_INIT_FCT keyboard int fct 583 (i.e. i8042_kbd_init()) 584 VIDEO_TSTC_FCT test char fct 585 (i.e. i8042_tstc) 586 VIDEO_GETC_FCT get char fct 587 (i.e. i8042_getc) 588 CONFIG_CONSOLE_CURSOR cursor drawing on/off 589 (requires blink timer 590 cf. i8042.c) 591 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 592 CONFIG_CONSOLE_TIME display time/date info in 593 upper right corner 594 (requires CONFIG_CMD_DATE) 595 CONFIG_VIDEO_LOGO display Linux logo in 596 upper left corner 597 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 598 linux_logo.h for logo. 599 Requires CONFIG_VIDEO_LOGO 600 CONFIG_CONSOLE_EXTRA_INFO 601 additional board info beside 602 the logo 603 604 When CONFIG_CFB_CONSOLE is defined, video console is 605 default i/o. Serial console can be forced with 606 environment 'console=serial'. 607 608 When CONFIG_SILENT_CONSOLE is defined, all console 609 messages (by U-Boot and Linux!) can be silenced with 610 the "silent" environment variable. See 611 doc/README.silent for more information. 612 613- Console Baudrate: 614 CONFIG_BAUDRATE - in bps 615 Select one of the baudrates listed in 616 CONFIG_SYS_BAUDRATE_TABLE, see below. 617 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 618 619- Console Rx buffer length 620 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 621 the maximum receive buffer length for the SMC. 622 This option is actual only for 82xx and 8xx possible. 623 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 624 must be defined, to setup the maximum idle timeout for 625 the SMC. 626 627- Pre-Console Buffer: 628 Prior to the console being initialised (i.e. serial UART 629 initialised etc) all console output is silently discarded. 630 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to 631 buffer any console messages prior to the console being 632 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ 633 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is 634 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ 635 bytes are output before the console is initialised, the 636 earlier bytes are discarded. 637 638 'Sane' compilers will generate smaller code if 639 CONFIG_PRE_CON_BUF_SZ is a power of 2 640 641- Pre-console putc(): 642 Prior to the console being initialised, console output is 643 normally silently discarded. This can be annoying if a 644 panic() happens in this time. 645 646 If the CONFIG_PRE_CONSOLE_PUTC option is defined, then 647 U-Boot will call board_pre_console_putc() for each output 648 character in this case, This function should try to output 649 the character if possible, perhaps on all available UARTs 650 (it will need to do this directly, since the console code 651 is not functional yet). Note that if the panic happens 652 early enough, then it is possible that board_init_f() 653 (or even arch_cpu_init() on ARM) has not been called yet. 654 You should init all clocks, GPIOs, etc. that are needed 655 to get the character out. Baud rates will need to default 656 to something sensible. 657 658- Boot Delay: CONFIG_BOOTDELAY - in seconds 659 Delay before automatically booting the default image; 660 set to -1 to disable autoboot. 661 662 See doc/README.autoboot for these options that 663 work with CONFIG_BOOTDELAY. None are required. 664 CONFIG_BOOT_RETRY_TIME 665 CONFIG_BOOT_RETRY_MIN 666 CONFIG_AUTOBOOT_KEYED 667 CONFIG_AUTOBOOT_PROMPT 668 CONFIG_AUTOBOOT_DELAY_STR 669 CONFIG_AUTOBOOT_STOP_STR 670 CONFIG_AUTOBOOT_DELAY_STR2 671 CONFIG_AUTOBOOT_STOP_STR2 672 CONFIG_ZERO_BOOTDELAY_CHECK 673 CONFIG_RESET_TO_RETRY 674 675- Autoboot Command: 676 CONFIG_BOOTCOMMAND 677 Only needed when CONFIG_BOOTDELAY is enabled; 678 define a command string that is automatically executed 679 when no character is read on the console interface 680 within "Boot Delay" after reset. 681 682 CONFIG_BOOTARGS 683 This can be used to pass arguments to the bootm 684 command. The value of CONFIG_BOOTARGS goes into the 685 environment value "bootargs". 686 687 CONFIG_RAMBOOT and CONFIG_NFSBOOT 688 The value of these goes into the environment as 689 "ramboot" and "nfsboot" respectively, and can be used 690 as a convenience, when switching between booting from 691 RAM and NFS. 692 693- Pre-Boot Commands: 694 CONFIG_PREBOOT 695 696 When this option is #defined, the existence of the 697 environment variable "preboot" will be checked 698 immediately before starting the CONFIG_BOOTDELAY 699 countdown and/or running the auto-boot command resp. 700 entering interactive mode. 701 702 This feature is especially useful when "preboot" is 703 automatically generated or modified. For an example 704 see the LWMON board specific code: here "preboot" is 705 modified when the user holds down a certain 706 combination of keys on the (special) keyboard when 707 booting the systems 708 709- Serial Download Echo Mode: 710 CONFIG_LOADS_ECHO 711 If defined to 1, all characters received during a 712 serial download (using the "loads" command) are 713 echoed back. This might be needed by some terminal 714 emulations (like "cu"), but may as well just take 715 time on others. This setting #define's the initial 716 value of the "loads_echo" environment variable. 717 718- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 719 CONFIG_KGDB_BAUDRATE 720 Select one of the baudrates listed in 721 CONFIG_SYS_BAUDRATE_TABLE, see below. 722 723- Monitor Functions: 724 Monitor commands can be included or excluded 725 from the build by using the #include files 726 "config_cmd_all.h" and #undef'ing unwanted 727 commands, or using "config_cmd_default.h" 728 and augmenting with additional #define's 729 for wanted commands. 730 731 The default command configuration includes all commands 732 except those marked below with a "*". 733 734 CONFIG_CMD_ASKENV * ask for env variable 735 CONFIG_CMD_BDI bdinfo 736 CONFIG_CMD_BEDBUG * Include BedBug Debugger 737 CONFIG_CMD_BMP * BMP support 738 CONFIG_CMD_BSP * Board specific commands 739 CONFIG_CMD_BOOTD bootd 740 CONFIG_CMD_CACHE * icache, dcache 741 CONFIG_CMD_CONSOLE coninfo 742 CONFIG_CMD_CRC32 * crc32 743 CONFIG_CMD_DATE * support for RTC, date/time... 744 CONFIG_CMD_DHCP * DHCP support 745 CONFIG_CMD_DIAG * Diagnostics 746 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands 747 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command 748 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd 749 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command 750 CONFIG_CMD_DTT * Digital Therm and Thermostat 751 CONFIG_CMD_ECHO echo arguments 752 CONFIG_CMD_EDITENV edit env variable 753 CONFIG_CMD_EEPROM * EEPROM read/write support 754 CONFIG_CMD_ELF * bootelf, bootvx 755 CONFIG_CMD_EXPORTENV * export the environment 756 CONFIG_CMD_SAVEENV saveenv 757 CONFIG_CMD_FDC * Floppy Disk Support 758 CONFIG_CMD_FAT * FAT partition support 759 CONFIG_CMD_FDOS * Dos diskette Support 760 CONFIG_CMD_FLASH flinfo, erase, protect 761 CONFIG_CMD_FPGA FPGA device initialization support 762 CONFIG_CMD_GO * the 'go' command (exec code) 763 CONFIG_CMD_GREPENV * search environment 764 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control 765 CONFIG_CMD_I2C * I2C serial bus support 766 CONFIG_CMD_IDE * IDE harddisk support 767 CONFIG_CMD_IMI iminfo 768 CONFIG_CMD_IMLS List all found images 769 CONFIG_CMD_IMMAP * IMMR dump support 770 CONFIG_CMD_IMPORTENV * import an environment 771 CONFIG_CMD_IRQ * irqinfo 772 CONFIG_CMD_ITEST Integer/string test of 2 values 773 CONFIG_CMD_JFFS2 * JFFS2 Support 774 CONFIG_CMD_KGDB * kgdb 775 CONFIG_CMD_LDRINFO ldrinfo (display Blackfin loader) 776 CONFIG_CMD_LOADB loadb 777 CONFIG_CMD_LOADS loads 778 CONFIG_CMD_MD5SUM print md5 message digest 779 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 780 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 781 loop, loopw, mtest 782 CONFIG_CMD_MISC Misc functions like sleep etc 783 CONFIG_CMD_MMC * MMC memory mapped support 784 CONFIG_CMD_MII * MII utility commands 785 CONFIG_CMD_MTDPARTS * MTD partition support 786 CONFIG_CMD_NAND * NAND support 787 CONFIG_CMD_NET bootp, tftpboot, rarpboot 788 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 789 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 790 CONFIG_CMD_PCI * pciinfo 791 CONFIG_CMD_PCMCIA * PCMCIA support 792 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 793 host 794 CONFIG_CMD_PORTIO * Port I/O 795 CONFIG_CMD_REGINFO * Register dump 796 CONFIG_CMD_RUN run command in env variable 797 CONFIG_CMD_SAVES * save S record dump 798 CONFIG_CMD_SCSI * SCSI Support 799 CONFIG_CMD_SDRAM * print SDRAM configuration information 800 (requires CONFIG_CMD_I2C) 801 CONFIG_CMD_SETGETDCR Support for DCR Register access 802 (4xx only) 803 CONFIG_CMD_SHA1SUM print sha1 memory digest 804 (requires CONFIG_CMD_MEMORY) 805 CONFIG_CMD_SOURCE "source" command Support 806 CONFIG_CMD_SPI * SPI serial bus support 807 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 808 CONFIG_CMD_TFTPPUT * TFTP put command (upload) 809 CONFIG_CMD_TIME * run command and report execution time 810 CONFIG_CMD_USB * USB support 811 CONFIG_CMD_CDP * Cisco Discover Protocol support 812 CONFIG_CMD_FSL * Microblaze FSL support 813 814 815 EXAMPLE: If you want all functions except of network 816 support you can write: 817 818 #include "config_cmd_all.h" 819 #undef CONFIG_CMD_NET 820 821 Other Commands: 822 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 823 824 Note: Don't enable the "icache" and "dcache" commands 825 (configuration option CONFIG_CMD_CACHE) unless you know 826 what you (and your U-Boot users) are doing. Data 827 cache cannot be enabled on systems like the 8xx or 828 8260 (where accesses to the IMMR region must be 829 uncached), and it cannot be disabled on all other 830 systems where we (mis-) use the data cache to hold an 831 initial stack and some data. 832 833 834 XXX - this list needs to get updated! 835 836- Device tree: 837 CONFIG_OF_CONTROL 838 If this variable is defined, U-Boot will use a device tree 839 to configure its devices, instead of relying on statically 840 compiled #defines in the board file. This option is 841 experimental and only available on a few boards. The device 842 tree is available in the global data as gd->fdt_blob. 843 844 U-Boot needs to get its device tree from somewhere. This can 845 be done using one of the two options below: 846 847 CONFIG_OF_EMBED 848 If this variable is defined, U-Boot will embed a device tree 849 binary in its image. This device tree file should be in the 850 board directory and called <soc>-<board>.dts. The binary file 851 is then picked up in board_init_f() and made available through 852 the global data structure as gd->blob. 853 854 CONFIG_OF_SEPARATE 855 If this variable is defined, U-Boot will build a device tree 856 binary. It will be called u-boot.dtb. Architecture-specific 857 code will locate it at run-time. Generally this works by: 858 859 cat u-boot.bin u-boot.dtb >image.bin 860 861 and in fact, U-Boot does this for you, creating a file called 862 u-boot-dtb.bin which is useful in the common case. You can 863 still use the individual files if you need something more 864 exotic. 865 866- Watchdog: 867 CONFIG_WATCHDOG 868 If this variable is defined, it enables watchdog 869 support for the SoC. There must be support in the SoC 870 specific code for a watchdog. For the 8xx and 8260 871 CPUs, the SIU Watchdog feature is enabled in the SYPCR 872 register. When supported for a specific SoC is 873 available, then no further board specific code should 874 be needed to use it. 875 876 CONFIG_HW_WATCHDOG 877 When using a watchdog circuitry external to the used 878 SoC, then define this variable and provide board 879 specific code for the "hw_watchdog_reset" function. 880 881- U-Boot Version: 882 CONFIG_VERSION_VARIABLE 883 If this variable is defined, an environment variable 884 named "ver" is created by U-Boot showing the U-Boot 885 version as printed by the "version" command. 886 This variable is readonly. 887 888- Real-Time Clock: 889 890 When CONFIG_CMD_DATE is selected, the type of the RTC 891 has to be selected, too. Define exactly one of the 892 following options: 893 894 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 895 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 896 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 897 CONFIG_RTC_MC146818 - use MC146818 RTC 898 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 899 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 900 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 901 CONFIG_RTC_DS164x - use Dallas DS164x RTC 902 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 903 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 904 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 905 CONFIG_SYS_RV3029_TCR - enable trickle charger on 906 RV3029 RTC. 907 908 Note that if the RTC uses I2C, then the I2C interface 909 must also be configured. See I2C Support, below. 910 911- GPIO Support: 912 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 913 CONFIG_PCA953X_INFO - enable pca953x info command 914 915 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 916 chip-ngpio pairs that tell the PCA953X driver the number of 917 pins supported by a particular chip. 918 919 Note that if the GPIO device uses I2C, then the I2C interface 920 must also be configured. See I2C Support, below. 921 922- Timestamp Support: 923 924 When CONFIG_TIMESTAMP is selected, the timestamp 925 (date and time) of an image is printed by image 926 commands like bootm or iminfo. This option is 927 automatically enabled when you select CONFIG_CMD_DATE . 928 929- Partition Support: 930 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION 931 and/or CONFIG_ISO_PARTITION and/or CONFIG_EFI_PARTITION 932 933 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 934 CONFIG_CMD_SCSI) you must configure support for at 935 least one partition type as well. 936 937- IDE Reset method: 938 CONFIG_IDE_RESET_ROUTINE - this is defined in several 939 board configurations files but used nowhere! 940 941 CONFIG_IDE_RESET - is this is defined, IDE Reset will 942 be performed by calling the function 943 ide_set_reset(int reset) 944 which has to be defined in a board specific file 945 946- ATAPI Support: 947 CONFIG_ATAPI 948 949 Set this to enable ATAPI support. 950 951- LBA48 Support 952 CONFIG_LBA48 953 954 Set this to enable support for disks larger than 137GB 955 Also look at CONFIG_SYS_64BIT_LBA. 956 Whithout these , LBA48 support uses 32bit variables and will 'only' 957 support disks up to 2.1TB. 958 959 CONFIG_SYS_64BIT_LBA: 960 When enabled, makes the IDE subsystem use 64bit sector addresses. 961 Default is 32bit. 962 963- SCSI Support: 964 At the moment only there is only support for the 965 SYM53C8XX SCSI controller; define 966 CONFIG_SCSI_SYM53C8XX to enable it. 967 968 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 969 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 970 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 971 maximum numbers of LUNs, SCSI ID's and target 972 devices. 973 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 974 975- NETWORK Support (PCI): 976 CONFIG_E1000 977 Support for Intel 8254x/8257x gigabit chips. 978 979 CONFIG_E1000_SPI 980 Utility code for direct access to the SPI bus on Intel 8257x. 981 This does not do anything useful unless you set at least one 982 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 983 984 CONFIG_E1000_SPI_GENERIC 985 Allow generic access to the SPI bus on the Intel 8257x, for 986 example with the "sspi" command. 987 988 CONFIG_CMD_E1000 989 Management command for E1000 devices. When used on devices 990 with SPI support you can reprogram the EEPROM from U-Boot. 991 992 CONFIG_E1000_FALLBACK_MAC 993 default MAC for empty EEPROM after production. 994 995 CONFIG_EEPRO100 996 Support for Intel 82557/82559/82559ER chips. 997 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 998 write routine for first time initialisation. 999 1000 CONFIG_TULIP 1001 Support for Digital 2114x chips. 1002 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 1003 modem chip initialisation (KS8761/QS6611). 1004 1005 CONFIG_NATSEMI 1006 Support for National dp83815 chips. 1007 1008 CONFIG_NS8382X 1009 Support for National dp8382[01] gigabit chips. 1010 1011- NETWORK Support (other): 1012 1013 CONFIG_DRIVER_AT91EMAC 1014 Support for AT91RM9200 EMAC. 1015 1016 CONFIG_RMII 1017 Define this to use reduced MII inteface 1018 1019 CONFIG_DRIVER_AT91EMAC_QUIET 1020 If this defined, the driver is quiet. 1021 The driver doen't show link status messages. 1022 1023 CONFIG_DRIVER_LAN91C96 1024 Support for SMSC's LAN91C96 chips. 1025 1026 CONFIG_LAN91C96_BASE 1027 Define this to hold the physical address 1028 of the LAN91C96's I/O space 1029 1030 CONFIG_LAN91C96_USE_32_BIT 1031 Define this to enable 32 bit addressing 1032 1033 CONFIG_DRIVER_SMC91111 1034 Support for SMSC's LAN91C111 chip 1035 1036 CONFIG_SMC91111_BASE 1037 Define this to hold the physical address 1038 of the device (I/O space) 1039 1040 CONFIG_SMC_USE_32_BIT 1041 Define this if data bus is 32 bits 1042 1043 CONFIG_SMC_USE_IOFUNCS 1044 Define this to use i/o functions instead of macros 1045 (some hardware wont work with macros) 1046 1047 CONFIG_DRIVER_TI_EMAC 1048 Support for davinci emac 1049 1050 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1051 Define this if you have more then 3 PHYs. 1052 1053 CONFIG_FTGMAC100 1054 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1055 1056 CONFIG_FTGMAC100_EGIGA 1057 Define this to use GE link update with gigabit PHY. 1058 Define this if FTGMAC100 is connected to gigabit PHY. 1059 If your system has 10/100 PHY only, it might not occur 1060 wrong behavior. Because PHY usually return timeout or 1061 useless data when polling gigabit status and gigabit 1062 control registers. This behavior won't affect the 1063 correctnessof 10/100 link speed update. 1064 1065 CONFIG_SMC911X 1066 Support for SMSC's LAN911x and LAN921x chips 1067 1068 CONFIG_SMC911X_BASE 1069 Define this to hold the physical address 1070 of the device (I/O space) 1071 1072 CONFIG_SMC911X_32_BIT 1073 Define this if data bus is 32 bits 1074 1075 CONFIG_SMC911X_16_BIT 1076 Define this if data bus is 16 bits. If your processor 1077 automatically converts one 32 bit word to two 16 bit 1078 words you may also try CONFIG_SMC911X_32_BIT. 1079 1080 CONFIG_SH_ETHER 1081 Support for Renesas on-chip Ethernet controller 1082 1083 CONFIG_SH_ETHER_USE_PORT 1084 Define the number of ports to be used 1085 1086 CONFIG_SH_ETHER_PHY_ADDR 1087 Define the ETH PHY's address 1088 1089 CONFIG_SH_ETHER_CACHE_WRITEBACK 1090 If this option is set, the driver enables cache flush. 1091 1092- TPM Support: 1093 CONFIG_GENERIC_LPC_TPM 1094 Support for generic parallel port TPM devices. Only one device 1095 per system is supported at this time. 1096 1097 CONFIG_TPM_TIS_BASE_ADDRESS 1098 Base address where the generic TPM device is mapped 1099 to. Contemporary x86 systems usually map it at 1100 0xfed40000. 1101 1102- USB Support: 1103 At the moment only the UHCI host controller is 1104 supported (PIP405, MIP405, MPC5200); define 1105 CONFIG_USB_UHCI to enable it. 1106 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1107 and define CONFIG_USB_STORAGE to enable the USB 1108 storage devices. 1109 Note: 1110 Supported are USB Keyboards and USB Floppy drives 1111 (TEAC FD-05PUB). 1112 MPC5200 USB requires additional defines: 1113 CONFIG_USB_CLOCK 1114 for 528 MHz Clock: 0x0001bbbb 1115 CONFIG_PSC3_USB 1116 for USB on PSC3 1117 CONFIG_USB_CONFIG 1118 for differential drivers: 0x00001000 1119 for single ended drivers: 0x00005000 1120 for differential drivers on PSC3: 0x00000100 1121 for single ended drivers on PSC3: 0x00004100 1122 CONFIG_SYS_USB_EVENT_POLL 1123 May be defined to allow interrupt polling 1124 instead of using asynchronous interrupts 1125 1126- USB Device: 1127 Define the below if you wish to use the USB console. 1128 Once firmware is rebuilt from a serial console issue the 1129 command "setenv stdin usbtty; setenv stdout usbtty" and 1130 attach your USB cable. The Unix command "dmesg" should print 1131 it has found a new device. The environment variable usbtty 1132 can be set to gserial or cdc_acm to enable your device to 1133 appear to a USB host as a Linux gserial device or a 1134 Common Device Class Abstract Control Model serial device. 1135 If you select usbtty = gserial you should be able to enumerate 1136 a Linux host by 1137 # modprobe usbserial vendor=0xVendorID product=0xProductID 1138 else if using cdc_acm, simply setting the environment 1139 variable usbtty to be cdc_acm should suffice. The following 1140 might be defined in YourBoardName.h 1141 1142 CONFIG_USB_DEVICE 1143 Define this to build a UDC device 1144 1145 CONFIG_USB_TTY 1146 Define this to have a tty type of device available to 1147 talk to the UDC device 1148 1149 CONFIG_SYS_CONSOLE_IS_IN_ENV 1150 Define this if you want stdin, stdout &/or stderr to 1151 be set to usbtty. 1152 1153 mpc8xx: 1154 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1155 Derive USB clock from external clock "blah" 1156 - CONFIG_SYS_USB_EXTC_CLK 0x02 1157 1158 CONFIG_SYS_USB_BRG_CLK 0xBLAH 1159 Derive USB clock from brgclk 1160 - CONFIG_SYS_USB_BRG_CLK 0x04 1161 1162 If you have a USB-IF assigned VendorID then you may wish to 1163 define your own vendor specific values either in BoardName.h 1164 or directly in usbd_vendor_info.h. If you don't define 1165 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1166 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1167 should pretend to be a Linux device to it's target host. 1168 1169 CONFIG_USBD_MANUFACTURER 1170 Define this string as the name of your company for 1171 - CONFIG_USBD_MANUFACTURER "my company" 1172 1173 CONFIG_USBD_PRODUCT_NAME 1174 Define this string as the name of your product 1175 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1176 1177 CONFIG_USBD_VENDORID 1178 Define this as your assigned Vendor ID from the USB 1179 Implementors Forum. This *must* be a genuine Vendor ID 1180 to avoid polluting the USB namespace. 1181 - CONFIG_USBD_VENDORID 0xFFFF 1182 1183 CONFIG_USBD_PRODUCTID 1184 Define this as the unique Product ID 1185 for your device 1186 - CONFIG_USBD_PRODUCTID 0xFFFF 1187 1188 1189- MMC Support: 1190 The MMC controller on the Intel PXA is supported. To 1191 enable this define CONFIG_MMC. The MMC can be 1192 accessed from the boot prompt by mapping the device 1193 to physical memory similar to flash. Command line is 1194 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1195 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1196 1197 CONFIG_SH_MMCIF 1198 Support for Renesas on-chip MMCIF controller 1199 1200 CONFIG_SH_MMCIF_ADDR 1201 Define the base address of MMCIF registers 1202 1203 CONFIG_SH_MMCIF_CLK 1204 Define the clock frequency for MMCIF 1205 1206- Journaling Flash filesystem support: 1207 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 1208 CONFIG_JFFS2_NAND_DEV 1209 Define these for a default partition on a NAND device 1210 1211 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1212 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1213 Define these for a default partition on a NOR device 1214 1215 CONFIG_SYS_JFFS_CUSTOM_PART 1216 Define this to create an own partition. You have to provide a 1217 function struct part_info* jffs2_part_info(int part_num) 1218 1219 If you define only one JFFS2 partition you may also want to 1220 #define CONFIG_SYS_JFFS_SINGLE_PART 1 1221 to disable the command chpart. This is the default when you 1222 have not defined a custom partition 1223 1224- FAT(File Allocation Table) filesystem write function support: 1225 CONFIG_FAT_WRITE 1226 Support for saving memory data as a file 1227 in FAT formatted partition 1228 1229- Keyboard Support: 1230 CONFIG_ISA_KEYBOARD 1231 1232 Define this to enable standard (PC-Style) keyboard 1233 support 1234 1235 CONFIG_I8042_KBD 1236 Standard PC keyboard driver with US (is default) and 1237 GERMAN key layout (switch via environment 'keymap=de') support. 1238 Export function i8042_kbd_init, i8042_tstc and i8042_getc 1239 for cfb_console. Supports cursor blinking. 1240 1241- Video support: 1242 CONFIG_VIDEO 1243 1244 Define this to enable video support (for output to 1245 video). 1246 1247 CONFIG_VIDEO_CT69000 1248 1249 Enable Chips & Technologies 69000 Video chip 1250 1251 CONFIG_VIDEO_SMI_LYNXEM 1252 Enable Silicon Motion SMI 712/710/810 Video chip. The 1253 video output is selected via environment 'videoout' 1254 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 1255 assumed. 1256 1257 For the CT69000 and SMI_LYNXEM drivers, videomode is 1258 selected via environment 'videomode'. Two different ways 1259 are possible: 1260 - "videomode=num" 'num' is a standard LiLo mode numbers. 1261 Following standard modes are supported (* is default): 1262 1263 Colors 640x480 800x600 1024x768 1152x864 1280x1024 1264 -------------+--------------------------------------------- 1265 8 bits | 0x301* 0x303 0x305 0x161 0x307 1266 15 bits | 0x310 0x313 0x316 0x162 0x319 1267 16 bits | 0x311 0x314 0x317 0x163 0x31A 1268 24 bits | 0x312 0x315 0x318 ? 0x31B 1269 -------------+--------------------------------------------- 1270 (i.e. setenv videomode 317; saveenv; reset;) 1271 1272 - "videomode=bootargs" all the video parameters are parsed 1273 from the bootargs. (See drivers/video/videomodes.c) 1274 1275 1276 CONFIG_VIDEO_SED13806 1277 Enable Epson SED13806 driver. This driver supports 8bpp 1278 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 1279 or CONFIG_VIDEO_SED13806_16BPP 1280 1281 CONFIG_FSL_DIU_FB 1282 Enable the Freescale DIU video driver. Reference boards for 1283 SOCs that have a DIU should define this macro to enable DIU 1284 support, and should also define these other macros: 1285 1286 CONFIG_SYS_DIU_ADDR 1287 CONFIG_VIDEO 1288 CONFIG_CMD_BMP 1289 CONFIG_CFB_CONSOLE 1290 CONFIG_VIDEO_SW_CURSOR 1291 CONFIG_VGA_AS_SINGLE_DEVICE 1292 CONFIG_VIDEO_LOGO 1293 CONFIG_VIDEO_BMP_LOGO 1294 1295 The DIU driver will look for the 'video-mode' environment 1296 variable, and if defined, enable the DIU as a console during 1297 boot. See the documentation file README.video for a 1298 description of this variable. 1299 1300- Keyboard Support: 1301 CONFIG_KEYBOARD 1302 1303 Define this to enable a custom keyboard support. 1304 This simply calls drv_keyboard_init() which must be 1305 defined in your board-specific files. 1306 The only board using this so far is RBC823. 1307 1308- LCD Support: CONFIG_LCD 1309 1310 Define this to enable LCD support (for output to LCD 1311 display); also select one of the supported displays 1312 by defining one of these: 1313 1314 CONFIG_ATMEL_LCD: 1315 1316 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1317 1318 CONFIG_NEC_NL6448AC33: 1319 1320 NEC NL6448AC33-18. Active, color, single scan. 1321 1322 CONFIG_NEC_NL6448BC20 1323 1324 NEC NL6448BC20-08. 6.5", 640x480. 1325 Active, color, single scan. 1326 1327 CONFIG_NEC_NL6448BC33_54 1328 1329 NEC NL6448BC33-54. 10.4", 640x480. 1330 Active, color, single scan. 1331 1332 CONFIG_SHARP_16x9 1333 1334 Sharp 320x240. Active, color, single scan. 1335 It isn't 16x9, and I am not sure what it is. 1336 1337 CONFIG_SHARP_LQ64D341 1338 1339 Sharp LQ64D341 display, 640x480. 1340 Active, color, single scan. 1341 1342 CONFIG_HLD1045 1343 1344 HLD1045 display, 640x480. 1345 Active, color, single scan. 1346 1347 CONFIG_OPTREX_BW 1348 1349 Optrex CBL50840-2 NF-FW 99 22 M5 1350 or 1351 Hitachi LMG6912RPFC-00T 1352 or 1353 Hitachi SP14Q002 1354 1355 320x240. Black & white. 1356 1357 Normally display is black on white background; define 1358 CONFIG_SYS_WHITE_ON_BLACK to get it inverted. 1359 1360- Splash Screen Support: CONFIG_SPLASH_SCREEN 1361 1362 If this option is set, the environment is checked for 1363 a variable "splashimage". If found, the usual display 1364 of logo, copyright and system information on the LCD 1365 is suppressed and the BMP image at the address 1366 specified in "splashimage" is loaded instead. The 1367 console is redirected to the "nulldev", too. This 1368 allows for a "silent" boot where a splash screen is 1369 loaded very quickly after power-on. 1370 1371 CONFIG_SPLASH_SCREEN_ALIGN 1372 1373 If this option is set the splash image can be freely positioned 1374 on the screen. Environment variable "splashpos" specifies the 1375 position as "x,y". If a positive number is given it is used as 1376 number of pixel from left/top. If a negative number is given it 1377 is used as number of pixel from right/bottom. You can also 1378 specify 'm' for centering the image. 1379 1380 Example: 1381 setenv splashpos m,m 1382 => image at center of screen 1383 1384 setenv splashpos 30,20 1385 => image at x = 30 and y = 20 1386 1387 setenv splashpos -10,m 1388 => vertically centered image 1389 at x = dspWidth - bmpWidth - 9 1390 1391- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1392 1393 If this option is set, additionally to standard BMP 1394 images, gzipped BMP images can be displayed via the 1395 splashscreen support or the bmp command. 1396 1397- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 1398 1399 If this option is set, 8-bit RLE compressed BMP images 1400 can be displayed via the splashscreen support or the 1401 bmp command. 1402 1403- Compression support: 1404 CONFIG_BZIP2 1405 1406 If this option is set, support for bzip2 compressed 1407 images is included. If not, only uncompressed and gzip 1408 compressed images are supported. 1409 1410 NOTE: the bzip2 algorithm requires a lot of RAM, so 1411 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 1412 be at least 4MB. 1413 1414 CONFIG_LZMA 1415 1416 If this option is set, support for lzma compressed 1417 images is included. 1418 1419 Note: The LZMA algorithm adds between 2 and 4KB of code and it 1420 requires an amount of dynamic memory that is given by the 1421 formula: 1422 1423 (1846 + 768 << (lc + lp)) * sizeof(uint16) 1424 1425 Where lc and lp stand for, respectively, Literal context bits 1426 and Literal pos bits. 1427 1428 This value is upper-bounded by 14MB in the worst case. Anyway, 1429 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 1430 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 1431 a very small buffer. 1432 1433 Use the lzmainfo tool to determinate the lc and lp values and 1434 then calculate the amount of needed dynamic memory (ensuring 1435 the appropriate CONFIG_SYS_MALLOC_LEN value). 1436 1437- MII/PHY support: 1438 CONFIG_PHY_ADDR 1439 1440 The address of PHY on MII bus. 1441 1442 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1443 1444 The clock frequency of the MII bus 1445 1446 CONFIG_PHY_GIGE 1447 1448 If this option is set, support for speed/duplex 1449 detection of gigabit PHY is included. 1450 1451 CONFIG_PHY_RESET_DELAY 1452 1453 Some PHY like Intel LXT971A need extra delay after 1454 reset before any MII register access is possible. 1455 For such PHY, set this option to the usec delay 1456 required. (minimum 300usec for LXT971A) 1457 1458 CONFIG_PHY_CMD_DELAY (ppc4xx) 1459 1460 Some PHY like Intel LXT971A need extra delay after 1461 command issued before MII status register can be read 1462 1463- Ethernet address: 1464 CONFIG_ETHADDR 1465 CONFIG_ETH1ADDR 1466 CONFIG_ETH2ADDR 1467 CONFIG_ETH3ADDR 1468 CONFIG_ETH4ADDR 1469 CONFIG_ETH5ADDR 1470 1471 Define a default value for Ethernet address to use 1472 for the respective Ethernet interface, in case this 1473 is not determined automatically. 1474 1475- IP address: 1476 CONFIG_IPADDR 1477 1478 Define a default value for the IP address to use for 1479 the default Ethernet interface, in case this is not 1480 determined through e.g. bootp. 1481 (Environment variable "ipaddr") 1482 1483- Server IP address: 1484 CONFIG_SERVERIP 1485 1486 Defines a default value for the IP address of a TFTP 1487 server to contact when using the "tftboot" command. 1488 (Environment variable "serverip") 1489 1490 CONFIG_KEEP_SERVERADDR 1491 1492 Keeps the server's MAC address, in the env 'serveraddr' 1493 for passing to bootargs (like Linux's netconsole option) 1494 1495- Gateway IP address: 1496 CONFIG_GATEWAYIP 1497 1498 Defines a default value for the IP address of the 1499 default router where packets to other networks are 1500 sent to. 1501 (Environment variable "gatewayip") 1502 1503- Subnet mask: 1504 CONFIG_NETMASK 1505 1506 Defines a default value for the subnet mask (or 1507 routing prefix) which is used to determine if an IP 1508 address belongs to the local subnet or needs to be 1509 forwarded through a router. 1510 (Environment variable "netmask") 1511 1512- Multicast TFTP Mode: 1513 CONFIG_MCAST_TFTP 1514 1515 Defines whether you want to support multicast TFTP as per 1516 rfc-2090; for example to work with atftp. Lets lots of targets 1517 tftp down the same boot image concurrently. Note: the Ethernet 1518 driver in use must provide a function: mcast() to join/leave a 1519 multicast group. 1520 1521- BOOTP Recovery Mode: 1522 CONFIG_BOOTP_RANDOM_DELAY 1523 1524 If you have many targets in a network that try to 1525 boot using BOOTP, you may want to avoid that all 1526 systems send out BOOTP requests at precisely the same 1527 moment (which would happen for instance at recovery 1528 from a power failure, when all systems will try to 1529 boot, thus flooding the BOOTP server. Defining 1530 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1531 inserted before sending out BOOTP requests. The 1532 following delays are inserted then: 1533 1534 1st BOOTP request: delay 0 ... 1 sec 1535 2nd BOOTP request: delay 0 ... 2 sec 1536 3rd BOOTP request: delay 0 ... 4 sec 1537 4th and following 1538 BOOTP requests: delay 0 ... 8 sec 1539 1540- DHCP Advanced Options: 1541 You can fine tune the DHCP functionality by defining 1542 CONFIG_BOOTP_* symbols: 1543 1544 CONFIG_BOOTP_SUBNETMASK 1545 CONFIG_BOOTP_GATEWAY 1546 CONFIG_BOOTP_HOSTNAME 1547 CONFIG_BOOTP_NISDOMAIN 1548 CONFIG_BOOTP_BOOTPATH 1549 CONFIG_BOOTP_BOOTFILESIZE 1550 CONFIG_BOOTP_DNS 1551 CONFIG_BOOTP_DNS2 1552 CONFIG_BOOTP_SEND_HOSTNAME 1553 CONFIG_BOOTP_NTPSERVER 1554 CONFIG_BOOTP_TIMEOFFSET 1555 CONFIG_BOOTP_VENDOREX 1556 1557 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 1558 environment variable, not the BOOTP server. 1559 1560 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 1561 serverip from a DHCP server, it is possible that more 1562 than one DNS serverip is offered to the client. 1563 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 1564 serverip will be stored in the additional environment 1565 variable "dnsip2". The first DNS serverip is always 1566 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 1567 is defined. 1568 1569 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 1570 to do a dynamic update of a DNS server. To do this, they 1571 need the hostname of the DHCP requester. 1572 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 1573 of the "hostname" environment variable is passed as 1574 option 12 to the DHCP server. 1575 1576 CONFIG_BOOTP_DHCP_REQUEST_DELAY 1577 1578 A 32bit value in microseconds for a delay between 1579 receiving a "DHCP Offer" and sending the "DHCP Request". 1580 This fixes a problem with certain DHCP servers that don't 1581 respond 100% of the time to a "DHCP request". E.g. On an 1582 AT91RM9200 processor running at 180MHz, this delay needed 1583 to be *at least* 15,000 usec before a Windows Server 2003 1584 DHCP server would reply 100% of the time. I recommend at 1585 least 50,000 usec to be safe. The alternative is to hope 1586 that one of the retries will be successful but note that 1587 the DHCP timeout and retry process takes a longer than 1588 this delay. 1589 1590 - CDP Options: 1591 CONFIG_CDP_DEVICE_ID 1592 1593 The device id used in CDP trigger frames. 1594 1595 CONFIG_CDP_DEVICE_ID_PREFIX 1596 1597 A two character string which is prefixed to the MAC address 1598 of the device. 1599 1600 CONFIG_CDP_PORT_ID 1601 1602 A printf format string which contains the ascii name of 1603 the port. Normally is set to "eth%d" which sets 1604 eth0 for the first Ethernet, eth1 for the second etc. 1605 1606 CONFIG_CDP_CAPABILITIES 1607 1608 A 32bit integer which indicates the device capabilities; 1609 0x00000010 for a normal host which does not forwards. 1610 1611 CONFIG_CDP_VERSION 1612 1613 An ascii string containing the version of the software. 1614 1615 CONFIG_CDP_PLATFORM 1616 1617 An ascii string containing the name of the platform. 1618 1619 CONFIG_CDP_TRIGGER 1620 1621 A 32bit integer sent on the trigger. 1622 1623 CONFIG_CDP_POWER_CONSUMPTION 1624 1625 A 16bit integer containing the power consumption of the 1626 device in .1 of milliwatts. 1627 1628 CONFIG_CDP_APPLIANCE_VLAN_TYPE 1629 1630 A byte containing the id of the VLAN. 1631 1632- Status LED: CONFIG_STATUS_LED 1633 1634 Several configurations allow to display the current 1635 status using a LED. For instance, the LED will blink 1636 fast while running U-Boot code, stop blinking as 1637 soon as a reply to a BOOTP request was received, and 1638 start blinking slow once the Linux kernel is running 1639 (supported by a status LED driver in the Linux 1640 kernel). Defining CONFIG_STATUS_LED enables this 1641 feature in U-Boot. 1642 1643- CAN Support: CONFIG_CAN_DRIVER 1644 1645 Defining CONFIG_CAN_DRIVER enables CAN driver support 1646 on those systems that support this (optional) 1647 feature, like the TQM8xxL modules. 1648 1649- I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C 1650 1651 These enable I2C serial bus commands. Defining either of 1652 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will 1653 include the appropriate I2C driver for the selected CPU. 1654 1655 This will allow you to use i2c commands at the u-boot 1656 command line (as long as you set CONFIG_CMD_I2C in 1657 CONFIG_COMMANDS) and communicate with i2c based realtime 1658 clock chips. See common/cmd_i2c.c for a description of the 1659 command line interface. 1660 1661 CONFIG_HARD_I2C selects a hardware I2C controller. 1662 1663 CONFIG_SOFT_I2C configures u-boot to use a software (aka 1664 bit-banging) driver instead of CPM or similar hardware 1665 support for I2C. 1666 1667 There are several other quantities that must also be 1668 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C. 1669 1670 In both cases you will need to define CONFIG_SYS_I2C_SPEED 1671 to be the frequency (in Hz) at which you wish your i2c bus 1672 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie 1673 the CPU's i2c node address). 1674 1675 Now, the u-boot i2c code for the mpc8xx 1676 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node 1677 and so its address should therefore be cleared to 0 (See, 1678 eg, MPC823e User's Manual p.16-473). So, set 1679 CONFIG_SYS_I2C_SLAVE to 0. 1680 1681 CONFIG_SYS_I2C_INIT_MPC5XXX 1682 1683 When a board is reset during an i2c bus transfer 1684 chips might think that the current transfer is still 1685 in progress. Reset the slave devices by sending start 1686 commands until the slave device responds. 1687 1688 That's all that's required for CONFIG_HARD_I2C. 1689 1690 If you use the software i2c interface (CONFIG_SOFT_I2C) 1691 then the following macros need to be defined (examples are 1692 from include/configs/lwmon.h): 1693 1694 I2C_INIT 1695 1696 (Optional). Any commands necessary to enable the I2C 1697 controller or configure ports. 1698 1699 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 1700 1701 I2C_PORT 1702 1703 (Only for MPC8260 CPU). The I/O port to use (the code 1704 assumes both bits are on the same port). Valid values 1705 are 0..3 for ports A..D. 1706 1707 I2C_ACTIVE 1708 1709 The code necessary to make the I2C data line active 1710 (driven). If the data line is open collector, this 1711 define can be null. 1712 1713 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 1714 1715 I2C_TRISTATE 1716 1717 The code necessary to make the I2C data line tri-stated 1718 (inactive). If the data line is open collector, this 1719 define can be null. 1720 1721 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 1722 1723 I2C_READ 1724 1725 Code that returns TRUE if the I2C data line is high, 1726 FALSE if it is low. 1727 1728 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 1729 1730 I2C_SDA(bit) 1731 1732 If <bit> is TRUE, sets the I2C data line high. If it 1733 is FALSE, it clears it (low). 1734 1735 eg: #define I2C_SDA(bit) \ 1736 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 1737 else immr->im_cpm.cp_pbdat &= ~PB_SDA 1738 1739 I2C_SCL(bit) 1740 1741 If <bit> is TRUE, sets the I2C clock line high. If it 1742 is FALSE, it clears it (low). 1743 1744 eg: #define I2C_SCL(bit) \ 1745 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 1746 else immr->im_cpm.cp_pbdat &= ~PB_SCL 1747 1748 I2C_DELAY 1749 1750 This delay is invoked four times per clock cycle so this 1751 controls the rate of data transfer. The data rate thus 1752 is 1 / (I2C_DELAY * 4). Often defined to be something 1753 like: 1754 1755 #define I2C_DELAY udelay(2) 1756 1757 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 1758 1759 If your arch supports the generic GPIO framework (asm/gpio.h), 1760 then you may alternatively define the two GPIOs that are to be 1761 used as SCL / SDA. Any of the previous I2C_xxx macros will 1762 have GPIO-based defaults assigned to them as appropriate. 1763 1764 You should define these to the GPIO value as given directly to 1765 the generic GPIO functions. 1766 1767 CONFIG_SYS_I2C_INIT_BOARD 1768 1769 When a board is reset during an i2c bus transfer 1770 chips might think that the current transfer is still 1771 in progress. On some boards it is possible to access 1772 the i2c SCLK line directly, either by using the 1773 processor pin as a GPIO or by having a second pin 1774 connected to the bus. If this option is defined a 1775 custom i2c_init_board() routine in boards/xxx/board.c 1776 is run early in the boot sequence. 1777 1778 CONFIG_SYS_I2C_BOARD_LATE_INIT 1779 1780 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is 1781 defined a custom i2c_board_late_init() routine in 1782 boards/xxx/board.c is run AFTER the operations in i2c_init() 1783 is completed. This callpoint can be used to unreset i2c bus 1784 using CPU i2c controller register accesses for CPUs whose i2c 1785 controller provide such a method. It is called at the end of 1786 i2c_init() to allow i2c_init operations to setup the i2c bus 1787 controller on the CPU (e.g. setting bus speed & slave address). 1788 1789 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 1790 1791 This option enables configuration of bi_iic_fast[] flags 1792 in u-boot bd_info structure based on u-boot environment 1793 variable "i2cfast". (see also i2cfast) 1794 1795 CONFIG_I2C_MULTI_BUS 1796 1797 This option allows the use of multiple I2C buses, each of which 1798 must have a controller. At any point in time, only one bus is 1799 active. To switch to a different bus, use the 'i2c dev' command. 1800 Note that bus numbering is zero-based. 1801 1802 CONFIG_SYS_I2C_NOPROBES 1803 1804 This option specifies a list of I2C devices that will be skipped 1805 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 1806 is set, specify a list of bus-device pairs. Otherwise, specify 1807 a 1D array of device addresses 1808 1809 e.g. 1810 #undef CONFIG_I2C_MULTI_BUS 1811 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 1812 1813 will skip addresses 0x50 and 0x68 on a board with one I2C bus 1814 1815 #define CONFIG_I2C_MULTI_BUS 1816 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 1817 1818 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 1819 1820 CONFIG_SYS_SPD_BUS_NUM 1821 1822 If defined, then this indicates the I2C bus number for DDR SPD. 1823 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 1824 1825 CONFIG_SYS_RTC_BUS_NUM 1826 1827 If defined, then this indicates the I2C bus number for the RTC. 1828 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 1829 1830 CONFIG_SYS_DTT_BUS_NUM 1831 1832 If defined, then this indicates the I2C bus number for the DTT. 1833 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 1834 1835 CONFIG_SYS_I2C_DTT_ADDR: 1836 1837 If defined, specifies the I2C address of the DTT device. 1838 If not defined, then U-Boot uses predefined value for 1839 specified DTT device. 1840 1841 CONFIG_FSL_I2C 1842 1843 Define this option if you want to use Freescale's I2C driver in 1844 drivers/i2c/fsl_i2c.c. 1845 1846 CONFIG_I2C_MUX 1847 1848 Define this option if you have I2C devices reached over 1 .. n 1849 I2C Muxes like the pca9544a. This option addes a new I2C 1850 Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a 1851 new I2C Bus to the existing I2C Busses. If you select the 1852 new Bus with "i2c dev", u-bbot sends first the commandos for 1853 the muxes to activate this new "bus". 1854 1855 CONFIG_I2C_MULTI_BUS must be also defined, to use this 1856 feature! 1857 1858 Example: 1859 Adding a new I2C Bus reached over 2 pca9544a muxes 1860 The First mux with address 70 and channel 6 1861 The Second mux with address 71 and channel 4 1862 1863 => i2c bus pca9544a:70:6:pca9544a:71:4 1864 1865 Use the "i2c bus" command without parameter, to get a list 1866 of I2C Busses with muxes: 1867 1868 => i2c bus 1869 Busses reached over muxes: 1870 Bus ID: 2 1871 reached over Mux(es): 1872 pca9544a@70 ch: 4 1873 Bus ID: 3 1874 reached over Mux(es): 1875 pca9544a@70 ch: 6 1876 pca9544a@71 ch: 4 1877 => 1878 1879 If you now switch to the new I2C Bus 3 with "i2c dev 3" 1880 u-boot first sends the command to the mux@70 to enable 1881 channel 6, and then the command to the mux@71 to enable 1882 the channel 4. 1883 1884 After that, you can use the "normal" i2c commands as 1885 usual to communicate with your I2C devices behind 1886 the 2 muxes. 1887 1888 This option is actually implemented for the bitbanging 1889 algorithm in common/soft_i2c.c and for the Hardware I2C 1890 Bus on the MPC8260. But it should be not so difficult 1891 to add this option to other architectures. 1892 1893 CONFIG_SOFT_I2C_READ_REPEATED_START 1894 1895 defining this will force the i2c_read() function in 1896 the soft_i2c driver to perform an I2C repeated start 1897 between writing the address pointer and reading the 1898 data. If this define is omitted the default behaviour 1899 of doing a stop-start sequence will be used. Most I2C 1900 devices can use either method, but some require one or 1901 the other. 1902 1903- SPI Support: CONFIG_SPI 1904 1905 Enables SPI driver (so far only tested with 1906 SPI EEPROM, also an instance works with Crystal A/D and 1907 D/As on the SACSng board) 1908 1909 CONFIG_SH_SPI 1910 1911 Enables the driver for SPI controller on SuperH. Currently 1912 only SH7757 is supported. 1913 1914 CONFIG_SPI_X 1915 1916 Enables extended (16-bit) SPI EEPROM addressing. 1917 (symmetrical to CONFIG_I2C_X) 1918 1919 CONFIG_SOFT_SPI 1920 1921 Enables a software (bit-bang) SPI driver rather than 1922 using hardware support. This is a general purpose 1923 driver that only requires three general I/O port pins 1924 (two outputs, one input) to function. If this is 1925 defined, the board configuration must define several 1926 SPI configuration items (port pins to use, etc). For 1927 an example, see include/configs/sacsng.h. 1928 1929 CONFIG_HARD_SPI 1930 1931 Enables a hardware SPI driver for general-purpose reads 1932 and writes. As with CONFIG_SOFT_SPI, the board configuration 1933 must define a list of chip-select function pointers. 1934 Currently supported on some MPC8xxx processors. For an 1935 example, see include/configs/mpc8349emds.h. 1936 1937 CONFIG_MXC_SPI 1938 1939 Enables the driver for the SPI controllers on i.MX and MXC 1940 SoCs. Currently i.MX31/35/51 are supported. 1941 1942- FPGA Support: CONFIG_FPGA 1943 1944 Enables FPGA subsystem. 1945 1946 CONFIG_FPGA_<vendor> 1947 1948 Enables support for specific chip vendors. 1949 (ALTERA, XILINX) 1950 1951 CONFIG_FPGA_<family> 1952 1953 Enables support for FPGA family. 1954 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 1955 1956 CONFIG_FPGA_COUNT 1957 1958 Specify the number of FPGA devices to support. 1959 1960 CONFIG_SYS_FPGA_PROG_FEEDBACK 1961 1962 Enable printing of hash marks during FPGA configuration. 1963 1964 CONFIG_SYS_FPGA_CHECK_BUSY 1965 1966 Enable checks on FPGA configuration interface busy 1967 status by the configuration function. This option 1968 will require a board or device specific function to 1969 be written. 1970 1971 CONFIG_FPGA_DELAY 1972 1973 If defined, a function that provides delays in the FPGA 1974 configuration driver. 1975 1976 CONFIG_SYS_FPGA_CHECK_CTRLC 1977 Allow Control-C to interrupt FPGA configuration 1978 1979 CONFIG_SYS_FPGA_CHECK_ERROR 1980 1981 Check for configuration errors during FPGA bitfile 1982 loading. For example, abort during Virtex II 1983 configuration if the INIT_B line goes low (which 1984 indicated a CRC error). 1985 1986 CONFIG_SYS_FPGA_WAIT_INIT 1987 1988 Maximum time to wait for the INIT_B line to deassert 1989 after PROB_B has been deasserted during a Virtex II 1990 FPGA configuration sequence. The default time is 500 1991 ms. 1992 1993 CONFIG_SYS_FPGA_WAIT_BUSY 1994 1995 Maximum time to wait for BUSY to deassert during 1996 Virtex II FPGA configuration. The default is 5 ms. 1997 1998 CONFIG_SYS_FPGA_WAIT_CONFIG 1999 2000 Time to wait after FPGA configuration. The default is 2001 200 ms. 2002 2003- Configuration Management: 2004 CONFIG_IDENT_STRING 2005 2006 If defined, this string will be added to the U-Boot 2007 version information (U_BOOT_VERSION) 2008 2009- Vendor Parameter Protection: 2010 2011 U-Boot considers the values of the environment 2012 variables "serial#" (Board Serial Number) and 2013 "ethaddr" (Ethernet Address) to be parameters that 2014 are set once by the board vendor / manufacturer, and 2015 protects these variables from casual modification by 2016 the user. Once set, these variables are read-only, 2017 and write or delete attempts are rejected. You can 2018 change this behaviour: 2019 2020 If CONFIG_ENV_OVERWRITE is #defined in your config 2021 file, the write protection for vendor parameters is 2022 completely disabled. Anybody can change or delete 2023 these parameters. 2024 2025 Alternatively, if you #define _both_ CONFIG_ETHADDR 2026 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2027 Ethernet address is installed in the environment, 2028 which can be changed exactly ONCE by the user. [The 2029 serial# is unaffected by this, i. e. it remains 2030 read-only.] 2031 2032- Protected RAM: 2033 CONFIG_PRAM 2034 2035 Define this variable to enable the reservation of 2036 "protected RAM", i. e. RAM which is not overwritten 2037 by U-Boot. Define CONFIG_PRAM to hold the number of 2038 kB you want to reserve for pRAM. You can overwrite 2039 this default value by defining an environment 2040 variable "pram" to the number of kB you want to 2041 reserve. Note that the board info structure will 2042 still show the full amount of RAM. If pRAM is 2043 reserved, a new environment variable "mem" will 2044 automatically be defined to hold the amount of 2045 remaining RAM in a form that can be passed as boot 2046 argument to Linux, for instance like that: 2047 2048 setenv bootargs ... mem=\${mem} 2049 saveenv 2050 2051 This way you can tell Linux not to use this memory, 2052 either, which results in a memory region that will 2053 not be affected by reboots. 2054 2055 *WARNING* If your board configuration uses automatic 2056 detection of the RAM size, you must make sure that 2057 this memory test is non-destructive. So far, the 2058 following board configurations are known to be 2059 "pRAM-clean": 2060 2061 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL, 2062 HERMES, IP860, RPXlite, LWMON, LANTEC, 2063 FLAGADM, TQM8260 2064 2065- Error Recovery: 2066 CONFIG_PANIC_HANG 2067 2068 Define this variable to stop the system in case of a 2069 fatal error, so that you have to reset it manually. 2070 This is probably NOT a good idea for an embedded 2071 system where you want the system to reboot 2072 automatically as fast as possible, but it may be 2073 useful during development since you can try to debug 2074 the conditions that lead to the situation. 2075 2076 CONFIG_NET_RETRY_COUNT 2077 2078 This variable defines the number of retries for 2079 network operations like ARP, RARP, TFTP, or BOOTP 2080 before giving up the operation. If not defined, a 2081 default value of 5 is used. 2082 2083 CONFIG_ARP_TIMEOUT 2084 2085 Timeout waiting for an ARP reply in milliseconds. 2086 2087- Command Interpreter: 2088 CONFIG_AUTO_COMPLETE 2089 2090 Enable auto completion of commands using TAB. 2091 2092 Note that this feature has NOT been implemented yet 2093 for the "hush" shell. 2094 2095 2096 CONFIG_SYS_HUSH_PARSER 2097 2098 Define this variable to enable the "hush" shell (from 2099 Busybox) as command line interpreter, thus enabling 2100 powerful command line syntax like 2101 if...then...else...fi conditionals or `&&' and '||' 2102 constructs ("shell scripts"). 2103 2104 If undefined, you get the old, much simpler behaviour 2105 with a somewhat smaller memory footprint. 2106 2107 2108 CONFIG_SYS_PROMPT_HUSH_PS2 2109 2110 This defines the secondary prompt string, which is 2111 printed when the command interpreter needs more input 2112 to complete a command. Usually "> ". 2113 2114 Note: 2115 2116 In the current implementation, the local variables 2117 space and global environment variables space are 2118 separated. Local variables are those you define by 2119 simply typing `name=value'. To access a local 2120 variable later on, you have write `$name' or 2121 `${name}'; to execute the contents of a variable 2122 directly type `$name' at the command prompt. 2123 2124 Global environment variables are those you use 2125 setenv/printenv to work with. To run a command stored 2126 in such a variable, you need to use the run command, 2127 and you must not use the '$' sign to access them. 2128 2129 To store commands and special characters in a 2130 variable, please use double quotation marks 2131 surrounding the whole text of the variable, instead 2132 of the backslashes before semicolons and special 2133 symbols. 2134 2135- Commandline Editing and History: 2136 CONFIG_CMDLINE_EDITING 2137 2138 Enable editing and History functions for interactive 2139 commandline input operations 2140 2141- Default Environment: 2142 CONFIG_EXTRA_ENV_SETTINGS 2143 2144 Define this to contain any number of null terminated 2145 strings (variable = value pairs) that will be part of 2146 the default environment compiled into the boot image. 2147 2148 For example, place something like this in your 2149 board's config file: 2150 2151 #define CONFIG_EXTRA_ENV_SETTINGS \ 2152 "myvar1=value1\0" \ 2153 "myvar2=value2\0" 2154 2155 Warning: This method is based on knowledge about the 2156 internal format how the environment is stored by the 2157 U-Boot code. This is NOT an official, exported 2158 interface! Although it is unlikely that this format 2159 will change soon, there is no guarantee either. 2160 You better know what you are doing here. 2161 2162 Note: overly (ab)use of the default environment is 2163 discouraged. Make sure to check other ways to preset 2164 the environment like the "source" command or the 2165 boot command first. 2166 2167- DataFlash Support: 2168 CONFIG_HAS_DATAFLASH 2169 2170 Defining this option enables DataFlash features and 2171 allows to read/write in Dataflash via the standard 2172 commands cp, md... 2173 2174- SystemACE Support: 2175 CONFIG_SYSTEMACE 2176 2177 Adding this option adds support for Xilinx SystemACE 2178 chips attached via some sort of local bus. The address 2179 of the chip must also be defined in the 2180 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 2181 2182 #define CONFIG_SYSTEMACE 2183 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 2184 2185 When SystemACE support is added, the "ace" device type 2186 becomes available to the fat commands, i.e. fatls. 2187 2188- TFTP Fixed UDP Port: 2189 CONFIG_TFTP_PORT 2190 2191 If this is defined, the environment variable tftpsrcp 2192 is used to supply the TFTP UDP source port value. 2193 If tftpsrcp isn't defined, the normal pseudo-random port 2194 number generator is used. 2195 2196 Also, the environment variable tftpdstp is used to supply 2197 the TFTP UDP destination port value. If tftpdstp isn't 2198 defined, the normal port 69 is used. 2199 2200 The purpose for tftpsrcp is to allow a TFTP server to 2201 blindly start the TFTP transfer using the pre-configured 2202 target IP address and UDP port. This has the effect of 2203 "punching through" the (Windows XP) firewall, allowing 2204 the remainder of the TFTP transfer to proceed normally. 2205 A better solution is to properly configure the firewall, 2206 but sometimes that is not allowed. 2207 2208- Show boot progress: 2209 CONFIG_SHOW_BOOT_PROGRESS 2210 2211 Defining this option allows to add some board- 2212 specific code (calling a user-provided function 2213 "show_boot_progress(int)") that enables you to show 2214 the system's boot progress on some display (for 2215 example, some LED's) on your board. At the moment, 2216 the following checkpoints are implemented: 2217 2218Legacy uImage format: 2219 2220 Arg Where When 2221 1 common/cmd_bootm.c before attempting to boot an image 2222 -1 common/cmd_bootm.c Image header has bad magic number 2223 2 common/cmd_bootm.c Image header has correct magic number 2224 -2 common/cmd_bootm.c Image header has bad checksum 2225 3 common/cmd_bootm.c Image header has correct checksum 2226 -3 common/cmd_bootm.c Image data has bad checksum 2227 4 common/cmd_bootm.c Image data has correct checksum 2228 -4 common/cmd_bootm.c Image is for unsupported architecture 2229 5 common/cmd_bootm.c Architecture check OK 2230 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 2231 6 common/cmd_bootm.c Image Type check OK 2232 -6 common/cmd_bootm.c gunzip uncompression error 2233 -7 common/cmd_bootm.c Unimplemented compression type 2234 7 common/cmd_bootm.c Uncompression OK 2235 8 common/cmd_bootm.c No uncompress/copy overwrite error 2236 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 2237 2238 9 common/image.c Start initial ramdisk verification 2239 -10 common/image.c Ramdisk header has bad magic number 2240 -11 common/image.c Ramdisk header has bad checksum 2241 10 common/image.c Ramdisk header is OK 2242 -12 common/image.c Ramdisk data has bad checksum 2243 11 common/image.c Ramdisk data has correct checksum 2244 12 common/image.c Ramdisk verification complete, start loading 2245 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 2246 13 common/image.c Start multifile image verification 2247 14 common/image.c No initial ramdisk, no multifile, continue. 2248 2249 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 2250 2251 -30 arch/powerpc/lib/board.c Fatal error, hang the system 2252 -31 post/post.c POST test failed, detected by post_output_backlog() 2253 -32 post/post.c POST test failed, detected by post_run_single() 2254 2255 34 common/cmd_doc.c before loading a Image from a DOC device 2256 -35 common/cmd_doc.c Bad usage of "doc" command 2257 35 common/cmd_doc.c correct usage of "doc" command 2258 -36 common/cmd_doc.c No boot device 2259 36 common/cmd_doc.c correct boot device 2260 -37 common/cmd_doc.c Unknown Chip ID on boot device 2261 37 common/cmd_doc.c correct chip ID found, device available 2262 -38 common/cmd_doc.c Read Error on boot device 2263 38 common/cmd_doc.c reading Image header from DOC device OK 2264 -39 common/cmd_doc.c Image header has bad magic number 2265 39 common/cmd_doc.c Image header has correct magic number 2266 -40 common/cmd_doc.c Error reading Image from DOC device 2267 40 common/cmd_doc.c Image header has correct magic number 2268 41 common/cmd_ide.c before loading a Image from a IDE device 2269 -42 common/cmd_ide.c Bad usage of "ide" command 2270 42 common/cmd_ide.c correct usage of "ide" command 2271 -43 common/cmd_ide.c No boot device 2272 43 common/cmd_ide.c boot device found 2273 -44 common/cmd_ide.c Device not available 2274 44 common/cmd_ide.c Device available 2275 -45 common/cmd_ide.c wrong partition selected 2276 45 common/cmd_ide.c partition selected 2277 -46 common/cmd_ide.c Unknown partition table 2278 46 common/cmd_ide.c valid partition table found 2279 -47 common/cmd_ide.c Invalid partition type 2280 47 common/cmd_ide.c correct partition type 2281 -48 common/cmd_ide.c Error reading Image Header on boot device 2282 48 common/cmd_ide.c reading Image Header from IDE device OK 2283 -49 common/cmd_ide.c Image header has bad magic number 2284 49 common/cmd_ide.c Image header has correct magic number 2285 -50 common/cmd_ide.c Image header has bad checksum 2286 50 common/cmd_ide.c Image header has correct checksum 2287 -51 common/cmd_ide.c Error reading Image from IDE device 2288 51 common/cmd_ide.c reading Image from IDE device OK 2289 52 common/cmd_nand.c before loading a Image from a NAND device 2290 -53 common/cmd_nand.c Bad usage of "nand" command 2291 53 common/cmd_nand.c correct usage of "nand" command 2292 -54 common/cmd_nand.c No boot device 2293 54 common/cmd_nand.c boot device found 2294 -55 common/cmd_nand.c Unknown Chip ID on boot device 2295 55 common/cmd_nand.c correct chip ID found, device available 2296 -56 common/cmd_nand.c Error reading Image Header on boot device 2297 56 common/cmd_nand.c reading Image Header from NAND device OK 2298 -57 common/cmd_nand.c Image header has bad magic number 2299 57 common/cmd_nand.c Image header has correct magic number 2300 -58 common/cmd_nand.c Error reading Image from NAND device 2301 58 common/cmd_nand.c reading Image from NAND device OK 2302 2303 -60 common/env_common.c Environment has a bad CRC, using default 2304 2305 64 net/eth.c starting with Ethernet configuration. 2306 -64 net/eth.c no Ethernet found. 2307 65 net/eth.c Ethernet found. 2308 2309 -80 common/cmd_net.c usage wrong 2310 80 common/cmd_net.c before calling NetLoop() 2311 -81 common/cmd_net.c some error in NetLoop() occurred 2312 81 common/cmd_net.c NetLoop() back without error 2313 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 2314 82 common/cmd_net.c trying automatic boot 2315 83 common/cmd_net.c running "source" command 2316 -83 common/cmd_net.c some error in automatic boot or "source" command 2317 84 common/cmd_net.c end without errors 2318 2319FIT uImage format: 2320 2321 Arg Where When 2322 100 common/cmd_bootm.c Kernel FIT Image has correct format 2323 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 2324 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 2325 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 2326 102 common/cmd_bootm.c Kernel unit name specified 2327 -103 common/cmd_bootm.c Can't get kernel subimage node offset 2328 103 common/cmd_bootm.c Found configuration node 2329 104 common/cmd_bootm.c Got kernel subimage node offset 2330 -104 common/cmd_bootm.c Kernel subimage hash verification failed 2331 105 common/cmd_bootm.c Kernel subimage hash verification OK 2332 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 2333 106 common/cmd_bootm.c Architecture check OK 2334 -106 common/cmd_bootm.c Kernel subimage has wrong type 2335 107 common/cmd_bootm.c Kernel subimage type OK 2336 -107 common/cmd_bootm.c Can't get kernel subimage data/size 2337 108 common/cmd_bootm.c Got kernel subimage data/size 2338 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 2339 -109 common/cmd_bootm.c Can't get kernel subimage type 2340 -110 common/cmd_bootm.c Can't get kernel subimage comp 2341 -111 common/cmd_bootm.c Can't get kernel subimage os 2342 -112 common/cmd_bootm.c Can't get kernel subimage load address 2343 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 2344 2345 120 common/image.c Start initial ramdisk verification 2346 -120 common/image.c Ramdisk FIT image has incorrect format 2347 121 common/image.c Ramdisk FIT image has correct format 2348 122 common/image.c No ramdisk subimage unit name, using configuration 2349 -122 common/image.c Can't get configuration for ramdisk subimage 2350 123 common/image.c Ramdisk unit name specified 2351 -124 common/image.c Can't get ramdisk subimage node offset 2352 125 common/image.c Got ramdisk subimage node offset 2353 -125 common/image.c Ramdisk subimage hash verification failed 2354 126 common/image.c Ramdisk subimage hash verification OK 2355 -126 common/image.c Ramdisk subimage for unsupported architecture 2356 127 common/image.c Architecture check OK 2357 -127 common/image.c Can't get ramdisk subimage data/size 2358 128 common/image.c Got ramdisk subimage data/size 2359 129 common/image.c Can't get ramdisk load address 2360 -129 common/image.c Got ramdisk load address 2361 2362 -130 common/cmd_doc.c Incorrect FIT image format 2363 131 common/cmd_doc.c FIT image format OK 2364 2365 -140 common/cmd_ide.c Incorrect FIT image format 2366 141 common/cmd_ide.c FIT image format OK 2367 2368 -150 common/cmd_nand.c Incorrect FIT image format 2369 151 common/cmd_nand.c FIT image format OK 2370 2371- Standalone program support: 2372 CONFIG_STANDALONE_LOAD_ADDR 2373 2374 This option defines a board specific value for the 2375 address where standalone program gets loaded, thus 2376 overwriting the architecture dependent default 2377 settings. 2378 2379- Frame Buffer Address: 2380 CONFIG_FB_ADDR 2381 2382 Define CONFIG_FB_ADDR if you want to use specific 2383 address for frame buffer. 2384 Then system will reserve the frame buffer address to 2385 defined address instead of lcd_setmem (this function 2386 grabs the memory for frame buffer by panel's size). 2387 2388 Please see board_init_f function. 2389 2390- Automatic software updates via TFTP server 2391 CONFIG_UPDATE_TFTP 2392 CONFIG_UPDATE_TFTP_CNT_MAX 2393 CONFIG_UPDATE_TFTP_MSEC_MAX 2394 2395 These options enable and control the auto-update feature; 2396 for a more detailed description refer to doc/README.update. 2397 2398- MTD Support (mtdparts command, UBI support) 2399 CONFIG_MTD_DEVICE 2400 2401 Adds the MTD device infrastructure from the Linux kernel. 2402 Needed for mtdparts command support. 2403 2404 CONFIG_MTD_PARTITIONS 2405 2406 Adds the MTD partitioning infrastructure from the Linux 2407 kernel. Needed for UBI support. 2408 2409- SPL framework 2410 CONFIG_SPL 2411 Enable building of SPL globally. 2412 2413 CONFIG_SPL_TEXT_BASE 2414 TEXT_BASE for linking the SPL binary. 2415 2416 CONFIG_SPL_LDSCRIPT 2417 LDSCRIPT for linking the SPL binary. 2418 2419 CONFIG_SPL_LIBCOMMON_SUPPORT 2420 Support for common/libcommon.o in SPL binary 2421 2422 CONFIG_SPL_LIBDISK_SUPPORT 2423 Support for disk/libdisk.o in SPL binary 2424 2425 CONFIG_SPL_I2C_SUPPORT 2426 Support for drivers/i2c/libi2c.o in SPL binary 2427 2428 CONFIG_SPL_GPIO_SUPPORT 2429 Support for drivers/gpio/libgpio.o in SPL binary 2430 2431 CONFIG_SPL_MMC_SUPPORT 2432 Support for drivers/mmc/libmmc.o in SPL binary 2433 2434 CONFIG_SPL_SERIAL_SUPPORT 2435 Support for drivers/serial/libserial.o in SPL binary 2436 2437 CONFIG_SPL_SPI_FLASH_SUPPORT 2438 Support for drivers/mtd/spi/libspi_flash.o in SPL binary 2439 2440 CONFIG_SPL_SPI_SUPPORT 2441 Support for drivers/spi/libspi.o in SPL binary 2442 2443 CONFIG_SPL_FAT_SUPPORT 2444 Support for fs/fat/libfat.o in SPL binary 2445 2446 CONFIG_SPL_LIBGENERIC_SUPPORT 2447 Support for lib/libgeneric.o in SPL binary 2448 2449Modem Support: 2450-------------- 2451 2452[so far only for SMDK2400 boards] 2453 2454- Modem support enable: 2455 CONFIG_MODEM_SUPPORT 2456 2457- RTS/CTS Flow control enable: 2458 CONFIG_HWFLOW 2459 2460- Modem debug support: 2461 CONFIG_MODEM_SUPPORT_DEBUG 2462 2463 Enables debugging stuff (char screen[1024], dbg()) 2464 for modem support. Useful only with BDI2000. 2465 2466- Interrupt support (PPC): 2467 2468 There are common interrupt_init() and timer_interrupt() 2469 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 2470 for CPU specific initialization. interrupt_init_cpu() 2471 should set decrementer_count to appropriate value. If 2472 CPU resets decrementer automatically after interrupt 2473 (ppc4xx) it should set decrementer_count to zero. 2474 timer_interrupt() calls timer_interrupt_cpu() for CPU 2475 specific handling. If board has watchdog / status_led 2476 / other_activity_monitor it works automatically from 2477 general timer_interrupt(). 2478 2479- General: 2480 2481 In the target system modem support is enabled when a 2482 specific key (key combination) is pressed during 2483 power-on. Otherwise U-Boot will boot normally 2484 (autoboot). The key_pressed() function is called from 2485 board_init(). Currently key_pressed() is a dummy 2486 function, returning 1 and thus enabling modem 2487 initialization. 2488 2489 If there are no modem init strings in the 2490 environment, U-Boot proceed to autoboot; the 2491 previous output (banner, info printfs) will be 2492 suppressed, though. 2493 2494 See also: doc/README.Modem 2495 2496Board initialization settings: 2497------------------------------ 2498 2499During Initialization u-boot calls a number of board specific functions 2500to allow the preparation of board specific prerequisites, e.g. pin setup 2501before drivers are initialized. To enable these callbacks the 2502following configuration macros have to be defined. Currently this is 2503architecture specific, so please check arch/your_architecture/lib/board.c 2504typically in board_init_f() and board_init_r(). 2505 2506- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 2507- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 2508- CONFIG_BOARD_LATE_INIT: Call board_late_init() 2509- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 2510 2511Configuration Settings: 2512----------------------- 2513 2514- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 2515 undefine this when you're short of memory. 2516 2517- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 2518 width of the commands listed in the 'help' command output. 2519 2520- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 2521 prompt for user input. 2522 2523- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 2524 2525- CONFIG_SYS_PBSIZE: Buffer size for Console output 2526 2527- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 2528 2529- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 2530 the application (usually a Linux kernel) when it is 2531 booted 2532 2533- CONFIG_SYS_BAUDRATE_TABLE: 2534 List of legal baudrate settings for this board. 2535 2536- CONFIG_SYS_CONSOLE_INFO_QUIET 2537 Suppress display of console information at boot. 2538 2539- CONFIG_SYS_CONSOLE_IS_IN_ENV 2540 If the board specific function 2541 extern int overwrite_console (void); 2542 returns 1, the stdin, stderr and stdout are switched to the 2543 serial port, else the settings in the environment are used. 2544 2545- CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE 2546 Enable the call to overwrite_console(). 2547 2548- CONFIG_SYS_CONSOLE_ENV_OVERWRITE 2549 Enable overwrite of previous console environment settings. 2550 2551- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 2552 Begin and End addresses of the area used by the 2553 simple memory test. 2554 2555- CONFIG_SYS_ALT_MEMTEST: 2556 Enable an alternate, more extensive memory test. 2557 2558- CONFIG_SYS_MEMTEST_SCRATCH: 2559 Scratch address used by the alternate memory test 2560 You only need to set this if address zero isn't writeable 2561 2562- CONFIG_SYS_MEM_TOP_HIDE (PPC only): 2563 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 2564 this specified memory area will get subtracted from the top 2565 (end) of RAM and won't get "touched" at all by U-Boot. By 2566 fixing up gd->ram_size the Linux kernel should gets passed 2567 the now "corrected" memory size and won't touch it either. 2568 This should work for arch/ppc and arch/powerpc. Only Linux 2569 board ports in arch/powerpc with bootwrapper support that 2570 recalculate the memory size from the SDRAM controller setup 2571 will have to get fixed in Linux additionally. 2572 2573 This option can be used as a workaround for the 440EPx/GRx 2574 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 2575 be touched. 2576 2577 WARNING: Please make sure that this value is a multiple of 2578 the Linux page size (normally 4k). If this is not the case, 2579 then the end address of the Linux memory will be located at a 2580 non page size aligned address and this could cause major 2581 problems. 2582 2583- CONFIG_SYS_TFTP_LOADADDR: 2584 Default load address for network file downloads 2585 2586- CONFIG_SYS_LOADS_BAUD_CHANGE: 2587 Enable temporary baudrate change while serial download 2588 2589- CONFIG_SYS_SDRAM_BASE: 2590 Physical start address of SDRAM. _Must_ be 0 here. 2591 2592- CONFIG_SYS_MBIO_BASE: 2593 Physical start address of Motherboard I/O (if using a 2594 Cogent motherboard) 2595 2596- CONFIG_SYS_FLASH_BASE: 2597 Physical start address of Flash memory. 2598 2599- CONFIG_SYS_MONITOR_BASE: 2600 Physical start address of boot monitor code (set by 2601 make config files to be same as the text base address 2602 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 2603 CONFIG_SYS_FLASH_BASE when booting from flash. 2604 2605- CONFIG_SYS_MONITOR_LEN: 2606 Size of memory reserved for monitor code, used to 2607 determine _at_compile_time_ (!) if the environment is 2608 embedded within the U-Boot image, or in a separate 2609 flash sector. 2610 2611- CONFIG_SYS_MALLOC_LEN: 2612 Size of DRAM reserved for malloc() use. 2613 2614- CONFIG_SYS_BOOTM_LEN: 2615 Normally compressed uImages are limited to an 2616 uncompressed size of 8 MBytes. If this is not enough, 2617 you can define CONFIG_SYS_BOOTM_LEN in your board config file 2618 to adjust this setting to your needs. 2619 2620- CONFIG_SYS_BOOTMAPSZ: 2621 Maximum size of memory mapped by the startup code of 2622 the Linux kernel; all data that must be processed by 2623 the Linux kernel (bd_info, boot arguments, FDT blob if 2624 used) must be put below this limit, unless "bootm_low" 2625 enviroment variable is defined and non-zero. In such case 2626 all data for the Linux kernel must be between "bootm_low" 2627 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 2628 variable "bootm_mapsize" will override the value of 2629 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 2630 then the value in "bootm_size" will be used instead. 2631 2632- CONFIG_SYS_BOOT_RAMDISK_HIGH: 2633 Enable initrd_high functionality. If defined then the 2634 initrd_high feature is enabled and the bootm ramdisk subcommand 2635 is enabled. 2636 2637- CONFIG_SYS_BOOT_GET_CMDLINE: 2638 Enables allocating and saving kernel cmdline in space between 2639 "bootm_low" and "bootm_low" + BOOTMAPSZ. 2640 2641- CONFIG_SYS_BOOT_GET_KBD: 2642 Enables allocating and saving a kernel copy of the bd_info in 2643 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 2644 2645- CONFIG_SYS_MAX_FLASH_BANKS: 2646 Max number of Flash memory banks 2647 2648- CONFIG_SYS_MAX_FLASH_SECT: 2649 Max number of sectors on a Flash chip 2650 2651- CONFIG_SYS_FLASH_ERASE_TOUT: 2652 Timeout for Flash erase operations (in ms) 2653 2654- CONFIG_SYS_FLASH_WRITE_TOUT: 2655 Timeout for Flash write operations (in ms) 2656 2657- CONFIG_SYS_FLASH_LOCK_TOUT 2658 Timeout for Flash set sector lock bit operation (in ms) 2659 2660- CONFIG_SYS_FLASH_UNLOCK_TOUT 2661 Timeout for Flash clear lock bits operation (in ms) 2662 2663- CONFIG_SYS_FLASH_PROTECTION 2664 If defined, hardware flash sectors protection is used 2665 instead of U-Boot software protection. 2666 2667- CONFIG_SYS_DIRECT_FLASH_TFTP: 2668 2669 Enable TFTP transfers directly to flash memory; 2670 without this option such a download has to be 2671 performed in two steps: (1) download to RAM, and (2) 2672 copy from RAM to flash. 2673 2674 The two-step approach is usually more reliable, since 2675 you can check if the download worked before you erase 2676 the flash, but in some situations (when system RAM is 2677 too limited to allow for a temporary copy of the 2678 downloaded image) this option may be very useful. 2679 2680- CONFIG_SYS_FLASH_CFI: 2681 Define if the flash driver uses extra elements in the 2682 common flash structure for storing flash geometry. 2683 2684- CONFIG_FLASH_CFI_DRIVER 2685 This option also enables the building of the cfi_flash driver 2686 in the drivers directory 2687 2688- CONFIG_FLASH_CFI_MTD 2689 This option enables the building of the cfi_mtd driver 2690 in the drivers directory. The driver exports CFI flash 2691 to the MTD layer. 2692 2693- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 2694 Use buffered writes to flash. 2695 2696- CONFIG_FLASH_SPANSION_S29WS_N 2697 s29ws-n MirrorBit flash has non-standard addresses for buffered 2698 write commands. 2699 2700- CONFIG_SYS_FLASH_QUIET_TEST 2701 If this option is defined, the common CFI flash doesn't 2702 print it's warning upon not recognized FLASH banks. This 2703 is useful, if some of the configured banks are only 2704 optionally available. 2705 2706- CONFIG_FLASH_SHOW_PROGRESS 2707 If defined (must be an integer), print out countdown 2708 digits and dots. Recommended value: 45 (9..1) for 80 2709 column displays, 15 (3..1) for 40 column displays. 2710 2711- CONFIG_SYS_RX_ETH_BUFFER: 2712 Defines the number of Ethernet receive buffers. On some 2713 Ethernet controllers it is recommended to set this value 2714 to 8 or even higher (EEPRO100 or 405 EMAC), since all 2715 buffers can be full shortly after enabling the interface 2716 on high Ethernet traffic. 2717 Defaults to 4 if not defined. 2718 2719- CONFIG_ENV_MAX_ENTRIES 2720 2721 Maximum number of entries in the hash table that is used 2722 internally to store the environment settings. The default 2723 setting is supposed to be generous and should work in most 2724 cases. This setting can be used to tune behaviour; see 2725 lib/hashtable.c for details. 2726 2727The following definitions that deal with the placement and management 2728of environment data (variable area); in general, we support the 2729following configurations: 2730 2731- CONFIG_BUILD_ENVCRC: 2732 2733 Builds up envcrc with the target environment so that external utils 2734 may easily extract it and embed it in final U-Boot images. 2735 2736- CONFIG_ENV_IS_IN_FLASH: 2737 2738 Define this if the environment is in flash memory. 2739 2740 a) The environment occupies one whole flash sector, which is 2741 "embedded" in the text segment with the U-Boot code. This 2742 happens usually with "bottom boot sector" or "top boot 2743 sector" type flash chips, which have several smaller 2744 sectors at the start or the end. For instance, such a 2745 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 2746 such a case you would place the environment in one of the 2747 4 kB sectors - with U-Boot code before and after it. With 2748 "top boot sector" type flash chips, you would put the 2749 environment in one of the last sectors, leaving a gap 2750 between U-Boot and the environment. 2751 2752 - CONFIG_ENV_OFFSET: 2753 2754 Offset of environment data (variable area) to the 2755 beginning of flash memory; for instance, with bottom boot 2756 type flash chips the second sector can be used: the offset 2757 for this sector is given here. 2758 2759 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 2760 2761 - CONFIG_ENV_ADDR: 2762 2763 This is just another way to specify the start address of 2764 the flash sector containing the environment (instead of 2765 CONFIG_ENV_OFFSET). 2766 2767 - CONFIG_ENV_SECT_SIZE: 2768 2769 Size of the sector containing the environment. 2770 2771 2772 b) Sometimes flash chips have few, equal sized, BIG sectors. 2773 In such a case you don't want to spend a whole sector for 2774 the environment. 2775 2776 - CONFIG_ENV_SIZE: 2777 2778 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 2779 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 2780 of this flash sector for the environment. This saves 2781 memory for the RAM copy of the environment. 2782 2783 It may also save flash memory if you decide to use this 2784 when your environment is "embedded" within U-Boot code, 2785 since then the remainder of the flash sector could be used 2786 for U-Boot code. It should be pointed out that this is 2787 STRONGLY DISCOURAGED from a robustness point of view: 2788 updating the environment in flash makes it always 2789 necessary to erase the WHOLE sector. If something goes 2790 wrong before the contents has been restored from a copy in 2791 RAM, your target system will be dead. 2792 2793 - CONFIG_ENV_ADDR_REDUND 2794 CONFIG_ENV_SIZE_REDUND 2795 2796 These settings describe a second storage area used to hold 2797 a redundant copy of the environment data, so that there is 2798 a valid backup copy in case there is a power failure during 2799 a "saveenv" operation. 2800 2801BE CAREFUL! Any changes to the flash layout, and some changes to the 2802source code will make it necessary to adapt <board>/u-boot.lds* 2803accordingly! 2804 2805 2806- CONFIG_ENV_IS_IN_NVRAM: 2807 2808 Define this if you have some non-volatile memory device 2809 (NVRAM, battery buffered SRAM) which you want to use for the 2810 environment. 2811 2812 - CONFIG_ENV_ADDR: 2813 - CONFIG_ENV_SIZE: 2814 2815 These two #defines are used to determine the memory area you 2816 want to use for environment. It is assumed that this memory 2817 can just be read and written to, without any special 2818 provision. 2819 2820BE CAREFUL! The first access to the environment happens quite early 2821in U-Boot initalization (when we try to get the setting of for the 2822console baudrate). You *MUST* have mapped your NVRAM area then, or 2823U-Boot will hang. 2824 2825Please note that even with NVRAM we still use a copy of the 2826environment in RAM: we could work on NVRAM directly, but we want to 2827keep settings there always unmodified except somebody uses "saveenv" 2828to save the current settings. 2829 2830 2831- CONFIG_ENV_IS_IN_EEPROM: 2832 2833 Use this if you have an EEPROM or similar serial access 2834 device and a driver for it. 2835 2836 - CONFIG_ENV_OFFSET: 2837 - CONFIG_ENV_SIZE: 2838 2839 These two #defines specify the offset and size of the 2840 environment area within the total memory of your EEPROM. 2841 2842 - CONFIG_SYS_I2C_EEPROM_ADDR: 2843 If defined, specified the chip address of the EEPROM device. 2844 The default address is zero. 2845 2846 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 2847 If defined, the number of bits used to address bytes in a 2848 single page in the EEPROM device. A 64 byte page, for example 2849 would require six bits. 2850 2851 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 2852 If defined, the number of milliseconds to delay between 2853 page writes. The default is zero milliseconds. 2854 2855 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 2856 The length in bytes of the EEPROM memory array address. Note 2857 that this is NOT the chip address length! 2858 2859 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 2860 EEPROM chips that implement "address overflow" are ones 2861 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 2862 address and the extra bits end up in the "chip address" bit 2863 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 2864 byte chips. 2865 2866 Note that we consider the length of the address field to 2867 still be one byte because the extra address bits are hidden 2868 in the chip address. 2869 2870 - CONFIG_SYS_EEPROM_SIZE: 2871 The size in bytes of the EEPROM device. 2872 2873 - CONFIG_ENV_EEPROM_IS_ON_I2C 2874 define this, if you have I2C and SPI activated, and your 2875 EEPROM, which holds the environment, is on the I2C bus. 2876 2877 - CONFIG_I2C_ENV_EEPROM_BUS 2878 if you have an Environment on an EEPROM reached over 2879 I2C muxes, you can define here, how to reach this 2880 EEPROM. For example: 2881 2882 #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0" 2883 2884 EEPROM which holds the environment, is reached over 2885 a pca9547 i2c mux with address 0x70, channel 3. 2886 2887- CONFIG_ENV_IS_IN_DATAFLASH: 2888 2889 Define this if you have a DataFlash memory device which you 2890 want to use for the environment. 2891 2892 - CONFIG_ENV_OFFSET: 2893 - CONFIG_ENV_ADDR: 2894 - CONFIG_ENV_SIZE: 2895 2896 These three #defines specify the offset and size of the 2897 environment area within the total memory of your DataFlash placed 2898 at the specified address. 2899 2900- CONFIG_ENV_IS_IN_NAND: 2901 2902 Define this if you have a NAND device which you want to use 2903 for the environment. 2904 2905 - CONFIG_ENV_OFFSET: 2906 - CONFIG_ENV_SIZE: 2907 2908 These two #defines specify the offset and size of the environment 2909 area within the first NAND device. CONFIG_ENV_OFFSET must be 2910 aligned to an erase block boundary. 2911 2912 - CONFIG_ENV_OFFSET_REDUND (optional): 2913 2914 This setting describes a second storage area of CONFIG_ENV_SIZE 2915 size used to hold a redundant copy of the environment data, so 2916 that there is a valid backup copy in case there is a power failure 2917 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 2918 aligned to an erase block boundary. 2919 2920 - CONFIG_ENV_RANGE (optional): 2921 2922 Specifies the length of the region in which the environment 2923 can be written. This should be a multiple of the NAND device's 2924 block size. Specifying a range with more erase blocks than 2925 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 2926 the range to be avoided. 2927 2928 - CONFIG_ENV_OFFSET_OOB (optional): 2929 2930 Enables support for dynamically retrieving the offset of the 2931 environment from block zero's out-of-band data. The 2932 "nand env.oob" command can be used to record this offset. 2933 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 2934 using CONFIG_ENV_OFFSET_OOB. 2935 2936- CONFIG_NAND_ENV_DST 2937 2938 Defines address in RAM to which the nand_spl code should copy the 2939 environment. If redundant environment is used, it will be copied to 2940 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 2941 2942- CONFIG_SYS_SPI_INIT_OFFSET 2943 2944 Defines offset to the initial SPI buffer area in DPRAM. The 2945 area is used at an early stage (ROM part) if the environment 2946 is configured to reside in the SPI EEPROM: We need a 520 byte 2947 scratch DPRAM area. It is used between the two initialization 2948 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 2949 to be a good choice since it makes it far enough from the 2950 start of the data area as well as from the stack pointer. 2951 2952Please note that the environment is read-only until the monitor 2953has been relocated to RAM and a RAM copy of the environment has been 2954created; also, when using EEPROM you will have to use getenv_f() 2955until then to read environment variables. 2956 2957The environment is protected by a CRC32 checksum. Before the monitor 2958is relocated into RAM, as a result of a bad CRC you will be working 2959with the compiled-in default environment - *silently*!!! [This is 2960necessary, because the first environment variable we need is the 2961"baudrate" setting for the console - if we have a bad CRC, we don't 2962have any device yet where we could complain.] 2963 2964Note: once the monitor has been relocated, then it will complain if 2965the default environment is used; a new CRC is computed as soon as you 2966use the "saveenv" command to store a valid environment. 2967 2968- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 2969 Echo the inverted Ethernet link state to the fault LED. 2970 2971 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 2972 also needs to be defined. 2973 2974- CONFIG_SYS_FAULT_MII_ADDR: 2975 MII address of the PHY to check for the Ethernet link state. 2976 2977- CONFIG_NS16550_MIN_FUNCTIONS: 2978 Define this if you desire to only have use of the NS16550_init 2979 and NS16550_putc functions for the serial driver located at 2980 drivers/serial/ns16550.c. This option is useful for saving 2981 space for already greatly restricted images, including but not 2982 limited to NAND_SPL configurations. 2983 2984Low Level (hardware related) configuration options: 2985--------------------------------------------------- 2986 2987- CONFIG_SYS_CACHELINE_SIZE: 2988 Cache Line Size of the CPU. 2989 2990- CONFIG_SYS_DEFAULT_IMMR: 2991 Default address of the IMMR after system reset. 2992 2993 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 2994 and RPXsuper) to be able to adjust the position of 2995 the IMMR register after a reset. 2996 2997- CONFIG_SYS_CCSRBAR_DEFAULT: 2998 Default (power-on reset) physical address of CCSR on Freescale 2999 PowerPC SOCs. 3000 3001- CONFIG_SYS_CCSRBAR: 3002 Virtual address of CCSR. On a 32-bit build, this is typically 3003 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 3004 3005 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 3006 for cross-platform code that uses that macro instead. 3007 3008- CONFIG_SYS_CCSRBAR_PHYS: 3009 Physical address of CCSR. CCSR can be relocated to a new 3010 physical address, if desired. In this case, this macro should 3011 be set to that address. Otherwise, it should be set to the 3012 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 3013 is typically relocated on 36-bit builds. It is recommended 3014 that this macro be defined via the _HIGH and _LOW macros: 3015 3016 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 3017 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 3018 3019- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 3020 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 3021 either 0 (32-bit build) or 0xF (36-bit build). This macro is 3022 used in assembly code, so it must not contain typecasts or 3023 integer size suffixes (e.g. "ULL"). 3024 3025- CONFIG_SYS_CCSRBAR_PHYS_LOW: 3026 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 3027 used in assembly code, so it must not contain typecasts or 3028 integer size suffixes (e.g. "ULL"). 3029 3030- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 3031 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 3032 forced to a value that ensures that CCSR is not relocated. 3033 3034- Floppy Disk Support: 3035 CONFIG_SYS_FDC_DRIVE_NUMBER 3036 3037 the default drive number (default value 0) 3038 3039 CONFIG_SYS_ISA_IO_STRIDE 3040 3041 defines the spacing between FDC chipset registers 3042 (default value 1) 3043 3044 CONFIG_SYS_ISA_IO_OFFSET 3045 3046 defines the offset of register from address. It 3047 depends on which part of the data bus is connected to 3048 the FDC chipset. (default value 0) 3049 3050 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 3051 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 3052 default value. 3053 3054 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 3055 fdc_hw_init() is called at the beginning of the FDC 3056 setup. fdc_hw_init() must be provided by the board 3057 source code. It is used to make hardware dependant 3058 initializations. 3059 3060- CONFIG_IDE_AHB: 3061 Most IDE controllers were designed to be connected with PCI 3062 interface. Only few of them were designed for AHB interface. 3063 When software is doing ATA command and data transfer to 3064 IDE devices through IDE-AHB controller, some additional 3065 registers accessing to these kind of IDE-AHB controller 3066 is requierd. 3067 3068- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 3069 DO NOT CHANGE unless you know exactly what you're 3070 doing! (11-4) [MPC8xx/82xx systems only] 3071 3072- CONFIG_SYS_INIT_RAM_ADDR: 3073 3074 Start address of memory area that can be used for 3075 initial data and stack; please note that this must be 3076 writable memory that is working WITHOUT special 3077 initialization, i. e. you CANNOT use normal RAM which 3078 will become available only after programming the 3079 memory controller and running certain initialization 3080 sequences. 3081 3082 U-Boot uses the following memory types: 3083 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 3084 - MPC824X: data cache 3085 - PPC4xx: data cache 3086 3087- CONFIG_SYS_GBL_DATA_OFFSET: 3088 3089 Offset of the initial data structure in the memory 3090 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 3091 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 3092 data is located at the end of the available space 3093 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 3094 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just 3095 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 3096 CONFIG_SYS_GBL_DATA_OFFSET) downward. 3097 3098 Note: 3099 On the MPC824X (or other systems that use the data 3100 cache for initial memory) the address chosen for 3101 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 3102 point to an otherwise UNUSED address space between 3103 the top of RAM and the start of the PCI space. 3104 3105- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 3106 3107- CONFIG_SYS_SYPCR: System Protection Control (11-9) 3108 3109- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 3110 3111- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 3112 3113- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 3114 3115- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 3116 3117- CONFIG_SYS_OR_TIMING_SDRAM: 3118 SDRAM timing 3119 3120- CONFIG_SYS_MAMR_PTA: 3121 periodic timer for refresh 3122 3123- CONFIG_SYS_DER: Debug Event Register (37-47) 3124 3125- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 3126 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 3127 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 3128 CONFIG_SYS_BR1_PRELIM: 3129 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 3130 3131- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 3132 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 3133 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 3134 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 3135 3136- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 3137 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 3138 Machine Mode Register and Memory Periodic Timer 3139 Prescaler definitions (SDRAM timing) 3140 3141- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 3142 enable I2C microcode relocation patch (MPC8xx); 3143 define relocation offset in DPRAM [DSP2] 3144 3145- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 3146 enable SMC microcode relocation patch (MPC8xx); 3147 define relocation offset in DPRAM [SMC1] 3148 3149- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 3150 enable SPI microcode relocation patch (MPC8xx); 3151 define relocation offset in DPRAM [SCC4] 3152 3153- CONFIG_SYS_USE_OSCCLK: 3154 Use OSCM clock mode on MBX8xx board. Be careful, 3155 wrong setting might damage your board. Read 3156 doc/README.MBX before setting this variable! 3157 3158- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 3159 Offset of the bootmode word in DPRAM used by post 3160 (Power On Self Tests). This definition overrides 3161 #define'd default value in commproc.h resp. 3162 cpm_8260.h. 3163 3164- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 3165 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 3166 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 3167 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 3168 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 3169 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 3170 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 3171 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 3172 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 3173 3174- CONFIG_PCI_DISABLE_PCIE: 3175 Disable PCI-Express on systems where it is supported but not 3176 required. 3177 3178- CONFIG_SYS_SRIO: 3179 Chip has SRIO or not 3180 3181- CONFIG_SRIO1: 3182 Board has SRIO 1 port available 3183 3184- CONFIG_SRIO2: 3185 Board has SRIO 2 port available 3186 3187- CONFIG_SYS_SRIOn_MEM_VIRT: 3188 Virtual Address of SRIO port 'n' memory region 3189 3190- CONFIG_SYS_SRIOn_MEM_PHYS: 3191 Physical Address of SRIO port 'n' memory region 3192 3193- CONFIG_SYS_SRIOn_MEM_SIZE: 3194 Size of SRIO port 'n' memory region 3195 3196- CONFIG_SYS_NDFC_16 3197 Defined to tell the NDFC that the NAND chip is using a 3198 16 bit bus. 3199 3200- CONFIG_SYS_NDFC_EBC0_CFG 3201 Sets the EBC0_CFG register for the NDFC. If not defined 3202 a default value will be used. 3203 3204- CONFIG_SPD_EEPROM 3205 Get DDR timing information from an I2C EEPROM. Common 3206 with pluggable memory modules such as SODIMMs 3207 3208 SPD_EEPROM_ADDRESS 3209 I2C address of the SPD EEPROM 3210 3211- CONFIG_SYS_SPD_BUS_NUM 3212 If SPD EEPROM is on an I2C bus other than the first 3213 one, specify here. Note that the value must resolve 3214 to something your driver can deal with. 3215 3216- CONFIG_SYS_DDR_RAW_TIMING 3217 Get DDR timing information from other than SPD. Common with 3218 soldered DDR chips onboard without SPD. DDR raw timing 3219 parameters are extracted from datasheet and hard-coded into 3220 header files or board specific files. 3221 3222- CONFIG_FSL_DDR_INTERACTIVE 3223 Enable interactive DDR debugging. See doc/README.fsl-ddr. 3224 3225- CONFIG_SYS_83XX_DDR_USES_CS0 3226 Only for 83xx systems. If specified, then DDR should 3227 be configured using CS0 and CS1 instead of CS2 and CS3. 3228 3229- CONFIG_ETHER_ON_FEC[12] 3230 Define to enable FEC[12] on a 8xx series processor. 3231 3232- CONFIG_FEC[12]_PHY 3233 Define to the hardcoded PHY address which corresponds 3234 to the given FEC; i. e. 3235 #define CONFIG_FEC1_PHY 4 3236 means that the PHY with address 4 is connected to FEC1 3237 3238 When set to -1, means to probe for first available. 3239 3240- CONFIG_FEC[12]_PHY_NORXERR 3241 The PHY does not have a RXERR line (RMII only). 3242 (so program the FEC to ignore it). 3243 3244- CONFIG_RMII 3245 Enable RMII mode for all FECs. 3246 Note that this is a global option, we can't 3247 have one FEC in standard MII mode and another in RMII mode. 3248 3249- CONFIG_CRC32_VERIFY 3250 Add a verify option to the crc32 command. 3251 The syntax is: 3252 3253 => crc32 -v <address> <count> <crc32> 3254 3255 Where address/count indicate a memory area 3256 and crc32 is the correct crc32 which the 3257 area should have. 3258 3259- CONFIG_LOOPW 3260 Add the "loopw" memory command. This only takes effect if 3261 the memory commands are activated globally (CONFIG_CMD_MEM). 3262 3263- CONFIG_MX_CYCLIC 3264 Add the "mdc" and "mwc" memory commands. These are cyclic 3265 "md/mw" commands. 3266 Examples: 3267 3268 => mdc.b 10 4 500 3269 This command will print 4 bytes (10,11,12,13) each 500 ms. 3270 3271 => mwc.l 100 12345678 10 3272 This command will write 12345678 to address 100 all 10 ms. 3273 3274 This only takes effect if the memory commands are activated 3275 globally (CONFIG_CMD_MEM). 3276 3277- CONFIG_SKIP_LOWLEVEL_INIT 3278 [ARM, NDS32, MIPS only] If this variable is defined, then certain 3279 low level initializations (like setting up the memory 3280 controller) are omitted and/or U-Boot does not 3281 relocate itself into RAM. 3282 3283 Normally this variable MUST NOT be defined. The only 3284 exception is when U-Boot is loaded (to RAM) by some 3285 other boot loader or by a debugger which performs 3286 these initializations itself. 3287 3288- CONFIG_SPL_BUILD 3289 Modifies the behaviour of start.S when compiling a loader 3290 that is executed before the actual U-Boot. E.g. when 3291 compiling a NAND SPL. 3292 3293- CONFIG_SYS_NAND_HW_ECC_OOBFIRST 3294 define this, if you want to read first the oob data 3295 and then the data. This is used for example on 3296 davinci plattforms. 3297 3298- CONFIG_USE_ARCH_MEMCPY 3299 CONFIG_USE_ARCH_MEMSET 3300 If these options are used a optimized version of memcpy/memset will 3301 be used if available. These functions may be faster under some 3302 conditions but may increase the binary size. 3303 3304Freescale QE/FMAN Firmware Support: 3305----------------------------------- 3306 3307The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 3308loading of "firmware", which is encoded in the QE firmware binary format. 3309This firmware often needs to be loaded during U-Boot booting, so macros 3310are used to identify the storage device (NOR flash, SPI, etc) and the address 3311within that device. 3312 3313- CONFIG_SYS_QE_FMAN_FW_ADDR 3314 The address in the storage device where the firmware is located. The 3315 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 3316 is also specified. 3317 3318- CONFIG_SYS_QE_FMAN_FW_LENGTH 3319 The maximum possible size of the firmware. The firmware binary format 3320 has a field that specifies the actual size of the firmware, but it 3321 might not be possible to read any part of the firmware unless some 3322 local storage is allocated to hold the entire firmware first. 3323 3324- CONFIG_SYS_QE_FMAN_FW_IN_NOR 3325 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 3326 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 3327 virtual address in NOR flash. 3328 3329- CONFIG_SYS_QE_FMAN_FW_IN_NAND 3330 Specifies that QE/FMAN firmware is located in NAND flash. 3331 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 3332 3333- CONFIG_SYS_QE_FMAN_FW_IN_MMC 3334 Specifies that QE/FMAN firmware is located on the primary SD/MMC 3335 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 3336 3337- CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH 3338 Specifies that QE/FMAN firmware is located on the primary SPI 3339 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 3340 3341 3342Building the Software: 3343====================== 3344 3345Building U-Boot has been tested in several native build environments 3346and in many different cross environments. Of course we cannot support 3347all possibly existing versions of cross development tools in all 3348(potentially obsolete) versions. In case of tool chain problems we 3349recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 3350which is extensively used to build and test U-Boot. 3351 3352If you are not using a native environment, it is assumed that you 3353have GNU cross compiling tools available in your path. In this case, 3354you must set the environment variable CROSS_COMPILE in your shell. 3355Note that no changes to the Makefile or any other source files are 3356necessary. For example using the ELDK on a 4xx CPU, please enter: 3357 3358 $ CROSS_COMPILE=ppc_4xx- 3359 $ export CROSS_COMPILE 3360 3361Note: If you wish to generate Windows versions of the utilities in 3362 the tools directory you can use the MinGW toolchain 3363 (http://www.mingw.org). Set your HOST tools to the MinGW 3364 toolchain and execute 'make tools'. For example: 3365 3366 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 3367 3368 Binaries such as tools/mkimage.exe will be created which can 3369 be executed on computers running Windows. 3370 3371U-Boot is intended to be simple to build. After installing the 3372sources you must configure U-Boot for one specific board type. This 3373is done by typing: 3374 3375 make NAME_config 3376 3377where "NAME_config" is the name of one of the existing configu- 3378rations; see the main Makefile for supported names. 3379 3380Note: for some board special configuration names may exist; check if 3381 additional information is available from the board vendor; for 3382 instance, the TQM823L systems are available without (standard) 3383 or with LCD support. You can select such additional "features" 3384 when choosing the configuration, i. e. 3385 3386 make TQM823L_config 3387 - will configure for a plain TQM823L, i. e. no LCD support 3388 3389 make TQM823L_LCD_config 3390 - will configure for a TQM823L with U-Boot console on LCD 3391 3392 etc. 3393 3394 3395Finally, type "make all", and you should get some working U-Boot 3396images ready for download to / installation on your system: 3397 3398- "u-boot.bin" is a raw binary image 3399- "u-boot" is an image in ELF binary format 3400- "u-boot.srec" is in Motorola S-Record format 3401 3402By default the build is performed locally and the objects are saved 3403in the source directory. One of the two methods can be used to change 3404this behavior and build U-Boot to some external directory: 3405 34061. Add O= to the make command line invocations: 3407 3408 make O=/tmp/build distclean 3409 make O=/tmp/build NAME_config 3410 make O=/tmp/build all 3411 34122. Set environment variable BUILD_DIR to point to the desired location: 3413 3414 export BUILD_DIR=/tmp/build 3415 make distclean 3416 make NAME_config 3417 make all 3418 3419Note that the command line "O=" setting overrides the BUILD_DIR environment 3420variable. 3421 3422 3423Please be aware that the Makefiles assume you are using GNU make, so 3424for instance on NetBSD you might need to use "gmake" instead of 3425native "make". 3426 3427 3428If the system board that you have is not listed, then you will need 3429to port U-Boot to your hardware platform. To do this, follow these 3430steps: 3431 34321. Add a new configuration option for your board to the toplevel 3433 "Makefile" and to the "MAKEALL" script, using the existing 3434 entries as examples. Note that here and at many other places 3435 boards and other names are listed in alphabetical sort order. Please 3436 keep this order. 34372. Create a new directory to hold your board specific code. Add any 3438 files you need. In your board directory, you will need at least 3439 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 34403. Create a new configuration file "include/configs/<board>.h" for 3441 your board 34423. If you're porting U-Boot to a new CPU, then also create a new 3443 directory to hold your CPU specific code. Add any files you need. 34444. Run "make <board>_config" with your new name. 34455. Type "make", and you should get a working "u-boot.srec" file 3446 to be installed on your target system. 34476. Debug and solve any problems that might arise. 3448 [Of course, this last step is much harder than it sounds.] 3449 3450 3451Testing of U-Boot Modifications, Ports to New Hardware, etc.: 3452============================================================== 3453 3454If you have modified U-Boot sources (for instance added a new board 3455or support for new devices, a new CPU, etc.) you are expected to 3456provide feedback to the other developers. The feedback normally takes 3457the form of a "patch", i. e. a context diff against a certain (latest 3458official or latest in the git repository) version of U-Boot sources. 3459 3460But before you submit such a patch, please verify that your modifi- 3461cation did not break existing code. At least make sure that *ALL* of 3462the supported boards compile WITHOUT ANY compiler warnings. To do so, 3463just run the "MAKEALL" script, which will configure and build U-Boot 3464for ALL supported system. Be warned, this will take a while. You can 3465select which (cross) compiler to use by passing a `CROSS_COMPILE' 3466environment variable to the script, i. e. to use the ELDK cross tools 3467you can type 3468 3469 CROSS_COMPILE=ppc_8xx- MAKEALL 3470 3471or to build on a native PowerPC system you can type 3472 3473 CROSS_COMPILE=' ' MAKEALL 3474 3475When using the MAKEALL script, the default behaviour is to build 3476U-Boot in the source directory. This location can be changed by 3477setting the BUILD_DIR environment variable. Also, for each target 3478built, the MAKEALL script saves two log files (<target>.ERR and 3479<target>.MAKEALL) in the <source dir>/LOG directory. This default 3480location can be changed by setting the MAKEALL_LOGDIR environment 3481variable. For example: 3482 3483 export BUILD_DIR=/tmp/build 3484 export MAKEALL_LOGDIR=/tmp/log 3485 CROSS_COMPILE=ppc_8xx- MAKEALL 3486 3487With the above settings build objects are saved in the /tmp/build, 3488log files are saved in the /tmp/log and the source tree remains clean 3489during the whole build process. 3490 3491 3492See also "U-Boot Porting Guide" below. 3493 3494 3495Monitor Commands - Overview: 3496============================ 3497 3498go - start application at address 'addr' 3499run - run commands in an environment variable 3500bootm - boot application image from memory 3501bootp - boot image via network using BootP/TFTP protocol 3502tftpboot- boot image via network using TFTP protocol 3503 and env variables "ipaddr" and "serverip" 3504 (and eventually "gatewayip") 3505tftpput - upload a file via network using TFTP protocol 3506rarpboot- boot image via network using RARP/TFTP protocol 3507diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 3508loads - load S-Record file over serial line 3509loadb - load binary file over serial line (kermit mode) 3510md - memory display 3511mm - memory modify (auto-incrementing) 3512nm - memory modify (constant address) 3513mw - memory write (fill) 3514cp - memory copy 3515cmp - memory compare 3516crc32 - checksum calculation 3517i2c - I2C sub-system 3518sspi - SPI utility commands 3519base - print or set address offset 3520printenv- print environment variables 3521setenv - set environment variables 3522saveenv - save environment variables to persistent storage 3523protect - enable or disable FLASH write protection 3524erase - erase FLASH memory 3525flinfo - print FLASH memory information 3526bdinfo - print Board Info structure 3527iminfo - print header information for application image 3528coninfo - print console devices and informations 3529ide - IDE sub-system 3530loop - infinite loop on address range 3531loopw - infinite write loop on address range 3532mtest - simple RAM test 3533icache - enable or disable instruction cache 3534dcache - enable or disable data cache 3535reset - Perform RESET of the CPU 3536echo - echo args to console 3537version - print monitor version 3538help - print online help 3539? - alias for 'help' 3540 3541 3542Monitor Commands - Detailed Description: 3543======================================== 3544 3545TODO. 3546 3547For now: just type "help <command>". 3548 3549 3550Environment Variables: 3551====================== 3552 3553U-Boot supports user configuration using Environment Variables which 3554can be made persistent by saving to Flash memory. 3555 3556Environment Variables are set using "setenv", printed using 3557"printenv", and saved to Flash using "saveenv". Using "setenv" 3558without a value can be used to delete a variable from the 3559environment. As long as you don't save the environment you are 3560working with an in-memory copy. In case the Flash area containing the 3561environment is erased by accident, a default environment is provided. 3562 3563Some configuration options can be set using Environment Variables. 3564 3565List of environment variables (most likely not complete): 3566 3567 baudrate - see CONFIG_BAUDRATE 3568 3569 bootdelay - see CONFIG_BOOTDELAY 3570 3571 bootcmd - see CONFIG_BOOTCOMMAND 3572 3573 bootargs - Boot arguments when booting an RTOS image 3574 3575 bootfile - Name of the image to load with TFTP 3576 3577 bootm_low - Memory range available for image processing in the bootm 3578 command can be restricted. This variable is given as 3579 a hexadecimal number and defines lowest address allowed 3580 for use by the bootm command. See also "bootm_size" 3581 environment variable. Address defined by "bootm_low" is 3582 also the base of the initial memory mapping for the Linux 3583 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 3584 bootm_mapsize. 3585 3586 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 3587 This variable is given as a hexadecimal number and it 3588 defines the size of the memory region starting at base 3589 address bootm_low that is accessible by the Linux kernel 3590 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 3591 as the default value if it is defined, and bootm_size is 3592 used otherwise. 3593 3594 bootm_size - Memory range available for image processing in the bootm 3595 command can be restricted. This variable is given as 3596 a hexadecimal number and defines the size of the region 3597 allowed for use by the bootm command. See also "bootm_low" 3598 environment variable. 3599 3600 updatefile - Location of the software update file on a TFTP server, used 3601 by the automatic software update feature. Please refer to 3602 documentation in doc/README.update for more details. 3603 3604 autoload - if set to "no" (any string beginning with 'n'), 3605 "bootp" will just load perform a lookup of the 3606 configuration from the BOOTP server, but not try to 3607 load any image using TFTP 3608 3609 autostart - if set to "yes", an image loaded using the "bootp", 3610 "rarpboot", "tftpboot" or "diskboot" commands will 3611 be automatically started (by internally calling 3612 "bootm") 3613 3614 If set to "no", a standalone image passed to the 3615 "bootm" command will be copied to the load address 3616 (and eventually uncompressed), but NOT be started. 3617 This can be used to load and uncompress arbitrary 3618 data. 3619 3620 fdt_high - if set this restricts the maximum address that the 3621 flattened device tree will be copied into upon boot. 3622 If this is set to the special value 0xFFFFFFFF then 3623 the fdt will not be copied at all on boot. For this 3624 to work it must reside in writable memory, have 3625 sufficient padding on the end of it for u-boot to 3626 add the information it needs into it, and the memory 3627 must be accessible by the kernel. 3628 3629 fdtcontroladdr- if set this is the address of the control flattened 3630 device tree used by U-Boot when CONFIG_OF_CONTROL is 3631 defined. 3632 3633 i2cfast - (PPC405GP|PPC405EP only) 3634 if set to 'y' configures Linux I2C driver for fast 3635 mode (400kHZ). This environment variable is used in 3636 initialization code. So, for changes to be effective 3637 it must be saved and board must be reset. 3638 3639 initrd_high - restrict positioning of initrd images: 3640 If this variable is not set, initrd images will be 3641 copied to the highest possible address in RAM; this 3642 is usually what you want since it allows for 3643 maximum initrd size. If for some reason you want to 3644 make sure that the initrd image is loaded below the 3645 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 3646 variable to a value of "no" or "off" or "0". 3647 Alternatively, you can set it to a maximum upper 3648 address to use (U-Boot will still check that it 3649 does not overwrite the U-Boot stack and data). 3650 3651 For instance, when you have a system with 16 MB 3652 RAM, and want to reserve 4 MB from use by Linux, 3653 you can do this by adding "mem=12M" to the value of 3654 the "bootargs" variable. However, now you must make 3655 sure that the initrd image is placed in the first 3656 12 MB as well - this can be done with 3657 3658 setenv initrd_high 00c00000 3659 3660 If you set initrd_high to 0xFFFFFFFF, this is an 3661 indication to U-Boot that all addresses are legal 3662 for the Linux kernel, including addresses in flash 3663 memory. In this case U-Boot will NOT COPY the 3664 ramdisk at all. This may be useful to reduce the 3665 boot time on your system, but requires that this 3666 feature is supported by your Linux kernel. 3667 3668 ipaddr - IP address; needed for tftpboot command 3669 3670 loadaddr - Default load address for commands like "bootp", 3671 "rarpboot", "tftpboot", "loadb" or "diskboot" 3672 3673 loads_echo - see CONFIG_LOADS_ECHO 3674 3675 serverip - TFTP server IP address; needed for tftpboot command 3676 3677 bootretry - see CONFIG_BOOT_RETRY_TIME 3678 3679 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 3680 3681 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 3682 3683 ethprime - controls which interface is used first. 3684 3685 ethact - controls which interface is currently active. 3686 For example you can do the following 3687 3688 => setenv ethact FEC 3689 => ping 192.168.0.1 # traffic sent on FEC 3690 => setenv ethact SCC 3691 => ping 10.0.0.1 # traffic sent on SCC 3692 3693 ethrotate - When set to "no" U-Boot does not go through all 3694 available network interfaces. 3695 It just stays at the currently selected interface. 3696 3697 netretry - When set to "no" each network operation will 3698 either succeed or fail without retrying. 3699 When set to "once" the network operation will 3700 fail when all the available network interfaces 3701 are tried once without success. 3702 Useful on scripts which control the retry operation 3703 themselves. 3704 3705 npe_ucode - set load address for the NPE microcode 3706 3707 tftpsrcport - If this is set, the value is used for TFTP's 3708 UDP source port. 3709 3710 tftpdstport - If this is set, the value is used for TFTP's UDP 3711 destination port instead of the Well Know Port 69. 3712 3713 tftpblocksize - Block size to use for TFTP transfers; if not set, 3714 we use the TFTP server's default block size 3715 3716 tftptimeout - Retransmission timeout for TFTP packets (in milli- 3717 seconds, minimum value is 1000 = 1 second). Defines 3718 when a packet is considered to be lost so it has to 3719 be retransmitted. The default is 5000 = 5 seconds. 3720 Lowering this value may make downloads succeed 3721 faster in networks with high packet loss rates or 3722 with unreliable TFTP servers. 3723 3724 vlan - When set to a value < 4095 the traffic over 3725 Ethernet is encapsulated/received over 802.1q 3726 VLAN tagged frames. 3727 3728The following image location variables contain the location of images 3729used in booting. The "Image" column gives the role of the image and is 3730not an environment variable name. The other columns are environment 3731variable names. "File Name" gives the name of the file on a TFTP 3732server, "RAM Address" gives the location in RAM the image will be 3733loaded to, and "Flash Location" gives the image's address in NOR 3734flash or offset in NAND flash. 3735 3736*Note* - these variables don't have to be defined for all boards, some 3737boards currenlty use other variables for these purposes, and some 3738boards use these variables for other purposes. 3739 3740Image File Name RAM Address Flash Location 3741----- --------- ----------- -------------- 3742u-boot u-boot u-boot_addr_r u-boot_addr 3743Linux kernel bootfile kernel_addr_r kernel_addr 3744device tree blob fdtfile fdt_addr_r fdt_addr 3745ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 3746 3747The following environment variables may be used and automatically 3748updated by the network boot commands ("bootp" and "rarpboot"), 3749depending the information provided by your boot server: 3750 3751 bootfile - see above 3752 dnsip - IP address of your Domain Name Server 3753 dnsip2 - IP address of your secondary Domain Name Server 3754 gatewayip - IP address of the Gateway (Router) to use 3755 hostname - Target hostname 3756 ipaddr - see above 3757 netmask - Subnet Mask 3758 rootpath - Pathname of the root filesystem on the NFS server 3759 serverip - see above 3760 3761 3762There are two special Environment Variables: 3763 3764 serial# - contains hardware identification information such 3765 as type string and/or serial number 3766 ethaddr - Ethernet address 3767 3768These variables can be set only once (usually during manufacturing of 3769the board). U-Boot refuses to delete or overwrite these variables 3770once they have been set once. 3771 3772 3773Further special Environment Variables: 3774 3775 ver - Contains the U-Boot version string as printed 3776 with the "version" command. This variable is 3777 readonly (see CONFIG_VERSION_VARIABLE). 3778 3779 3780Please note that changes to some configuration parameters may take 3781only effect after the next boot (yes, that's just like Windoze :-). 3782 3783 3784Command Line Parsing: 3785===================== 3786 3787There are two different command line parsers available with U-Boot: 3788the old "simple" one, and the much more powerful "hush" shell: 3789 3790Old, simple command line parser: 3791-------------------------------- 3792 3793- supports environment variables (through setenv / saveenv commands) 3794- several commands on one line, separated by ';' 3795- variable substitution using "... ${name} ..." syntax 3796- special characters ('$', ';') can be escaped by prefixing with '\', 3797 for example: 3798 setenv bootcmd bootm \${address} 3799- You can also escape text by enclosing in single apostrophes, for example: 3800 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 3801 3802Hush shell: 3803----------- 3804 3805- similar to Bourne shell, with control structures like 3806 if...then...else...fi, for...do...done; while...do...done, 3807 until...do...done, ... 3808- supports environment ("global") variables (through setenv / saveenv 3809 commands) and local shell variables (through standard shell syntax 3810 "name=value"); only environment variables can be used with "run" 3811 command 3812 3813General rules: 3814-------------- 3815 3816(1) If a command line (or an environment variable executed by a "run" 3817 command) contains several commands separated by semicolon, and 3818 one of these commands fails, then the remaining commands will be 3819 executed anyway. 3820 3821(2) If you execute several variables with one call to run (i. e. 3822 calling run with a list of variables as arguments), any failing 3823 command will cause "run" to terminate, i. e. the remaining 3824 variables are not executed. 3825 3826Note for Redundant Ethernet Interfaces: 3827======================================= 3828 3829Some boards come with redundant Ethernet interfaces; U-Boot supports 3830such configurations and is capable of automatic selection of a 3831"working" interface when needed. MAC assignment works as follows: 3832 3833Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 3834MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 3835"eth1addr" (=>eth1), "eth2addr", ... 3836 3837If the network interface stores some valid MAC address (for instance 3838in SROM), this is used as default address if there is NO correspon- 3839ding setting in the environment; if the corresponding environment 3840variable is set, this overrides the settings in the card; that means: 3841 3842o If the SROM has a valid MAC address, and there is no address in the 3843 environment, the SROM's address is used. 3844 3845o If there is no valid address in the SROM, and a definition in the 3846 environment exists, then the value from the environment variable is 3847 used. 3848 3849o If both the SROM and the environment contain a MAC address, and 3850 both addresses are the same, this MAC address is used. 3851 3852o If both the SROM and the environment contain a MAC address, and the 3853 addresses differ, the value from the environment is used and a 3854 warning is printed. 3855 3856o If neither SROM nor the environment contain a MAC address, an error 3857 is raised. 3858 3859If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 3860will be programmed into hardware as part of the initialization process. This 3861may be skipped by setting the appropriate 'ethmacskip' environment variable. 3862The naming convention is as follows: 3863"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 3864 3865Image Formats: 3866============== 3867 3868U-Boot is capable of booting (and performing other auxiliary operations on) 3869images in two formats: 3870 3871New uImage format (FIT) 3872----------------------- 3873 3874Flexible and powerful format based on Flattened Image Tree -- FIT (similar 3875to Flattened Device Tree). It allows the use of images with multiple 3876components (several kernels, ramdisks, etc.), with contents protected by 3877SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 3878 3879 3880Old uImage format 3881----------------- 3882 3883Old image format is based on binary files which can be basically anything, 3884preceded by a special header; see the definitions in include/image.h for 3885details; basically, the header defines the following image properties: 3886 3887* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 3888 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 3889 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 3890 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 3891 INTEGRITY). 3892* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 3893 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 3894 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 3895* Compression Type (uncompressed, gzip, bzip2) 3896* Load Address 3897* Entry Point 3898* Image Name 3899* Image Timestamp 3900 3901The header is marked by a special Magic Number, and both the header 3902and the data portions of the image are secured against corruption by 3903CRC32 checksums. 3904 3905 3906Linux Support: 3907============== 3908 3909Although U-Boot should support any OS or standalone application 3910easily, the main focus has always been on Linux during the design of 3911U-Boot. 3912 3913U-Boot includes many features that so far have been part of some 3914special "boot loader" code within the Linux kernel. Also, any 3915"initrd" images to be used are no longer part of one big Linux image; 3916instead, kernel and "initrd" are separate images. This implementation 3917serves several purposes: 3918 3919- the same features can be used for other OS or standalone 3920 applications (for instance: using compressed images to reduce the 3921 Flash memory footprint) 3922 3923- it becomes much easier to port new Linux kernel versions because 3924 lots of low-level, hardware dependent stuff are done by U-Boot 3925 3926- the same Linux kernel image can now be used with different "initrd" 3927 images; of course this also means that different kernel images can 3928 be run with the same "initrd". This makes testing easier (you don't 3929 have to build a new "zImage.initrd" Linux image when you just 3930 change a file in your "initrd"). Also, a field-upgrade of the 3931 software is easier now. 3932 3933 3934Linux HOWTO: 3935============ 3936 3937Porting Linux to U-Boot based systems: 3938--------------------------------------- 3939 3940U-Boot cannot save you from doing all the necessary modifications to 3941configure the Linux device drivers for use with your target hardware 3942(no, we don't intend to provide a full virtual machine interface to 3943Linux :-). 3944 3945But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 3946 3947Just make sure your machine specific header file (for instance 3948include/asm-ppc/tqm8xx.h) includes the same definition of the Board 3949Information structure as we define in include/asm-<arch>/u-boot.h, 3950and make sure that your definition of IMAP_ADDR uses the same value 3951as your U-Boot configuration in CONFIG_SYS_IMMR. 3952 3953 3954Configuring the Linux kernel: 3955----------------------------- 3956 3957No specific requirements for U-Boot. Make sure you have some root 3958device (initial ramdisk, NFS) for your target system. 3959 3960 3961Building a Linux Image: 3962----------------------- 3963 3964With U-Boot, "normal" build targets like "zImage" or "bzImage" are 3965not used. If you use recent kernel source, a new build target 3966"uImage" will exist which automatically builds an image usable by 3967U-Boot. Most older kernels also have support for a "pImage" target, 3968which was introduced for our predecessor project PPCBoot and uses a 3969100% compatible format. 3970 3971Example: 3972 3973 make TQM850L_config 3974 make oldconfig 3975 make dep 3976 make uImage 3977 3978The "uImage" build target uses a special tool (in 'tools/mkimage') to 3979encapsulate a compressed Linux kernel image with header information, 3980CRC32 checksum etc. for use with U-Boot. This is what we are doing: 3981 3982* build a standard "vmlinux" kernel image (in ELF binary format): 3983 3984* convert the kernel into a raw binary image: 3985 3986 ${CROSS_COMPILE}-objcopy -O binary \ 3987 -R .note -R .comment \ 3988 -S vmlinux linux.bin 3989 3990* compress the binary image: 3991 3992 gzip -9 linux.bin 3993 3994* package compressed binary image for U-Boot: 3995 3996 mkimage -A ppc -O linux -T kernel -C gzip \ 3997 -a 0 -e 0 -n "Linux Kernel Image" \ 3998 -d linux.bin.gz uImage 3999 4000 4001The "mkimage" tool can also be used to create ramdisk images for use 4002with U-Boot, either separated from the Linux kernel image, or 4003combined into one file. "mkimage" encapsulates the images with a 64 4004byte header containing information about target architecture, 4005operating system, image type, compression method, entry points, time 4006stamp, CRC32 checksums, etc. 4007 4008"mkimage" can be called in two ways: to verify existing images and 4009print the header information, or to build new images. 4010 4011In the first form (with "-l" option) mkimage lists the information 4012contained in the header of an existing U-Boot image; this includes 4013checksum verification: 4014 4015 tools/mkimage -l image 4016 -l ==> list image header information 4017 4018The second form (with "-d" option) is used to build a U-Boot image 4019from a "data file" which is used as image payload: 4020 4021 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 4022 -n name -d data_file image 4023 -A ==> set architecture to 'arch' 4024 -O ==> set operating system to 'os' 4025 -T ==> set image type to 'type' 4026 -C ==> set compression type 'comp' 4027 -a ==> set load address to 'addr' (hex) 4028 -e ==> set entry point to 'ep' (hex) 4029 -n ==> set image name to 'name' 4030 -d ==> use image data from 'datafile' 4031 4032Right now, all Linux kernels for PowerPC systems use the same load 4033address (0x00000000), but the entry point address depends on the 4034kernel version: 4035 4036- 2.2.x kernels have the entry point at 0x0000000C, 4037- 2.3.x and later kernels have the entry point at 0x00000000. 4038 4039So a typical call to build a U-Boot image would read: 4040 4041 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 4042 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 4043 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 4044 > examples/uImage.TQM850L 4045 Image Name: 2.4.4 kernel for TQM850L 4046 Created: Wed Jul 19 02:34:59 2000 4047 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4048 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 4049 Load Address: 0x00000000 4050 Entry Point: 0x00000000 4051 4052To verify the contents of the image (or check for corruption): 4053 4054 -> tools/mkimage -l examples/uImage.TQM850L 4055 Image Name: 2.4.4 kernel for TQM850L 4056 Created: Wed Jul 19 02:34:59 2000 4057 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4058 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 4059 Load Address: 0x00000000 4060 Entry Point: 0x00000000 4061 4062NOTE: for embedded systems where boot time is critical you can trade 4063speed for memory and install an UNCOMPRESSED image instead: this 4064needs more space in Flash, but boots much faster since it does not 4065need to be uncompressed: 4066 4067 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 4068 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 4069 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 4070 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 4071 > examples/uImage.TQM850L-uncompressed 4072 Image Name: 2.4.4 kernel for TQM850L 4073 Created: Wed Jul 19 02:34:59 2000 4074 Image Type: PowerPC Linux Kernel Image (uncompressed) 4075 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 4076 Load Address: 0x00000000 4077 Entry Point: 0x00000000 4078 4079 4080Similar you can build U-Boot images from a 'ramdisk.image.gz' file 4081when your kernel is intended to use an initial ramdisk: 4082 4083 -> tools/mkimage -n 'Simple Ramdisk Image' \ 4084 > -A ppc -O linux -T ramdisk -C gzip \ 4085 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 4086 Image Name: Simple Ramdisk Image 4087 Created: Wed Jan 12 14:01:50 2000 4088 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 4089 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 4090 Load Address: 0x00000000 4091 Entry Point: 0x00000000 4092 4093 4094Installing a Linux Image: 4095------------------------- 4096 4097To downloading a U-Boot image over the serial (console) interface, 4098you must convert the image to S-Record format: 4099 4100 objcopy -I binary -O srec examples/image examples/image.srec 4101 4102The 'objcopy' does not understand the information in the U-Boot 4103image header, so the resulting S-Record file will be relative to 4104address 0x00000000. To load it to a given address, you need to 4105specify the target address as 'offset' parameter with the 'loads' 4106command. 4107 4108Example: install the image to address 0x40100000 (which on the 4109TQM8xxL is in the first Flash bank): 4110 4111 => erase 40100000 401FFFFF 4112 4113 .......... done 4114 Erased 8 sectors 4115 4116 => loads 40100000 4117 ## Ready for S-Record download ... 4118 ~>examples/image.srec 4119 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 4120 ... 4121 15989 15990 15991 15992 4122 [file transfer complete] 4123 [connected] 4124 ## Start Addr = 0x00000000 4125 4126 4127You can check the success of the download using the 'iminfo' command; 4128this includes a checksum verification so you can be sure no data 4129corruption happened: 4130 4131 => imi 40100000 4132 4133 ## Checking Image at 40100000 ... 4134 Image Name: 2.2.13 for initrd on TQM850L 4135 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4136 Data Size: 335725 Bytes = 327 kB = 0 MB 4137 Load Address: 00000000 4138 Entry Point: 0000000c 4139 Verifying Checksum ... OK 4140 4141 4142Boot Linux: 4143----------- 4144 4145The "bootm" command is used to boot an application that is stored in 4146memory (RAM or Flash). In case of a Linux kernel image, the contents 4147of the "bootargs" environment variable is passed to the kernel as 4148parameters. You can check and modify this variable using the 4149"printenv" and "setenv" commands: 4150 4151 4152 => printenv bootargs 4153 bootargs=root=/dev/ram 4154 4155 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 4156 4157 => printenv bootargs 4158 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 4159 4160 => bootm 40020000 4161 ## Booting Linux kernel at 40020000 ... 4162 Image Name: 2.2.13 for NFS on TQM850L 4163 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4164 Data Size: 381681 Bytes = 372 kB = 0 MB 4165 Load Address: 00000000 4166 Entry Point: 0000000c 4167 Verifying Checksum ... OK 4168 Uncompressing Kernel Image ... OK 4169 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 4170 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 4171 time_init: decrementer frequency = 187500000/60 4172 Calibrating delay loop... 49.77 BogoMIPS 4173 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 4174 ... 4175 4176If you want to boot a Linux kernel with initial RAM disk, you pass 4177the memory addresses of both the kernel and the initrd image (PPBCOOT 4178format!) to the "bootm" command: 4179 4180 => imi 40100000 40200000 4181 4182 ## Checking Image at 40100000 ... 4183 Image Name: 2.2.13 for initrd on TQM850L 4184 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4185 Data Size: 335725 Bytes = 327 kB = 0 MB 4186 Load Address: 00000000 4187 Entry Point: 0000000c 4188 Verifying Checksum ... OK 4189 4190 ## Checking Image at 40200000 ... 4191 Image Name: Simple Ramdisk Image 4192 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 4193 Data Size: 566530 Bytes = 553 kB = 0 MB 4194 Load Address: 00000000 4195 Entry Point: 00000000 4196 Verifying Checksum ... OK 4197 4198 => bootm 40100000 40200000 4199 ## Booting Linux kernel at 40100000 ... 4200 Image Name: 2.2.13 for initrd on TQM850L 4201 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4202 Data Size: 335725 Bytes = 327 kB = 0 MB 4203 Load Address: 00000000 4204 Entry Point: 0000000c 4205 Verifying Checksum ... OK 4206 Uncompressing Kernel Image ... OK 4207 ## Loading RAMDisk Image at 40200000 ... 4208 Image Name: Simple Ramdisk Image 4209 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 4210 Data Size: 566530 Bytes = 553 kB = 0 MB 4211 Load Address: 00000000 4212 Entry Point: 00000000 4213 Verifying Checksum ... OK 4214 Loading Ramdisk ... OK 4215 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 4216 Boot arguments: root=/dev/ram 4217 time_init: decrementer frequency = 187500000/60 4218 Calibrating delay loop... 49.77 BogoMIPS 4219 ... 4220 RAMDISK: Compressed image found at block 0 4221 VFS: Mounted root (ext2 filesystem). 4222 4223 bash# 4224 4225Boot Linux and pass a flat device tree: 4226----------- 4227 4228First, U-Boot must be compiled with the appropriate defines. See the section 4229titled "Linux Kernel Interface" above for a more in depth explanation. The 4230following is an example of how to start a kernel and pass an updated 4231flat device tree: 4232 4233=> print oftaddr 4234oftaddr=0x300000 4235=> print oft 4236oft=oftrees/mpc8540ads.dtb 4237=> tftp $oftaddr $oft 4238Speed: 1000, full duplex 4239Using TSEC0 device 4240TFTP from server 192.168.1.1; our IP address is 192.168.1.101 4241Filename 'oftrees/mpc8540ads.dtb'. 4242Load address: 0x300000 4243Loading: # 4244done 4245Bytes transferred = 4106 (100a hex) 4246=> tftp $loadaddr $bootfile 4247Speed: 1000, full duplex 4248Using TSEC0 device 4249TFTP from server 192.168.1.1; our IP address is 192.168.1.2 4250Filename 'uImage'. 4251Load address: 0x200000 4252Loading:############ 4253done 4254Bytes transferred = 1029407 (fb51f hex) 4255=> print loadaddr 4256loadaddr=200000 4257=> print oftaddr 4258oftaddr=0x300000 4259=> bootm $loadaddr - $oftaddr 4260## Booting image at 00200000 ... 4261 Image Name: Linux-2.6.17-dirty 4262 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4263 Data Size: 1029343 Bytes = 1005.2 kB 4264 Load Address: 00000000 4265 Entry Point: 00000000 4266 Verifying Checksum ... OK 4267 Uncompressing Kernel Image ... OK 4268Booting using flat device tree at 0x300000 4269Using MPC85xx ADS machine description 4270Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 4271[snip] 4272 4273 4274More About U-Boot Image Types: 4275------------------------------ 4276 4277U-Boot supports the following image types: 4278 4279 "Standalone Programs" are directly runnable in the environment 4280 provided by U-Boot; it is expected that (if they behave 4281 well) you can continue to work in U-Boot after return from 4282 the Standalone Program. 4283 "OS Kernel Images" are usually images of some Embedded OS which 4284 will take over control completely. Usually these programs 4285 will install their own set of exception handlers, device 4286 drivers, set up the MMU, etc. - this means, that you cannot 4287 expect to re-enter U-Boot except by resetting the CPU. 4288 "RAMDisk Images" are more or less just data blocks, and their 4289 parameters (address, size) are passed to an OS kernel that is 4290 being started. 4291 "Multi-File Images" contain several images, typically an OS 4292 (Linux) kernel image and one or more data images like 4293 RAMDisks. This construct is useful for instance when you want 4294 to boot over the network using BOOTP etc., where the boot 4295 server provides just a single image file, but you want to get 4296 for instance an OS kernel and a RAMDisk image. 4297 4298 "Multi-File Images" start with a list of image sizes, each 4299 image size (in bytes) specified by an "uint32_t" in network 4300 byte order. This list is terminated by an "(uint32_t)0". 4301 Immediately after the terminating 0 follow the images, one by 4302 one, all aligned on "uint32_t" boundaries (size rounded up to 4303 a multiple of 4 bytes). 4304 4305 "Firmware Images" are binary images containing firmware (like 4306 U-Boot or FPGA images) which usually will be programmed to 4307 flash memory. 4308 4309 "Script files" are command sequences that will be executed by 4310 U-Boot's command interpreter; this feature is especially 4311 useful when you configure U-Boot to use a real shell (hush) 4312 as command interpreter. 4313 4314 4315Standalone HOWTO: 4316================= 4317 4318One of the features of U-Boot is that you can dynamically load and 4319run "standalone" applications, which can use some resources of 4320U-Boot like console I/O functions or interrupt services. 4321 4322Two simple examples are included with the sources: 4323 4324"Hello World" Demo: 4325------------------- 4326 4327'examples/hello_world.c' contains a small "Hello World" Demo 4328application; it is automatically compiled when you build U-Boot. 4329It's configured to run at address 0x00040004, so you can play with it 4330like that: 4331 4332 => loads 4333 ## Ready for S-Record download ... 4334 ~>examples/hello_world.srec 4335 1 2 3 4 5 6 7 8 9 10 11 ... 4336 [file transfer complete] 4337 [connected] 4338 ## Start Addr = 0x00040004 4339 4340 => go 40004 Hello World! This is a test. 4341 ## Starting application at 0x00040004 ... 4342 Hello World 4343 argc = 7 4344 argv[0] = "40004" 4345 argv[1] = "Hello" 4346 argv[2] = "World!" 4347 argv[3] = "This" 4348 argv[4] = "is" 4349 argv[5] = "a" 4350 argv[6] = "test." 4351 argv[7] = "<NULL>" 4352 Hit any key to exit ... 4353 4354 ## Application terminated, rc = 0x0 4355 4356Another example, which demonstrates how to register a CPM interrupt 4357handler with the U-Boot code, can be found in 'examples/timer.c'. 4358Here, a CPM timer is set up to generate an interrupt every second. 4359The interrupt service routine is trivial, just printing a '.' 4360character, but this is just a demo program. The application can be 4361controlled by the following keys: 4362 4363 ? - print current values og the CPM Timer registers 4364 b - enable interrupts and start timer 4365 e - stop timer and disable interrupts 4366 q - quit application 4367 4368 => loads 4369 ## Ready for S-Record download ... 4370 ~>examples/timer.srec 4371 1 2 3 4 5 6 7 8 9 10 11 ... 4372 [file transfer complete] 4373 [connected] 4374 ## Start Addr = 0x00040004 4375 4376 => go 40004 4377 ## Starting application at 0x00040004 ... 4378 TIMERS=0xfff00980 4379 Using timer 1 4380 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 4381 4382Hit 'b': 4383 [q, b, e, ?] Set interval 1000000 us 4384 Enabling timer 4385Hit '?': 4386 [q, b, e, ?] ........ 4387 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 4388Hit '?': 4389 [q, b, e, ?] . 4390 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 4391Hit '?': 4392 [q, b, e, ?] . 4393 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 4394Hit '?': 4395 [q, b, e, ?] . 4396 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 4397Hit 'e': 4398 [q, b, e, ?] ...Stopping timer 4399Hit 'q': 4400 [q, b, e, ?] ## Application terminated, rc = 0x0 4401 4402 4403Minicom warning: 4404================ 4405 4406Over time, many people have reported problems when trying to use the 4407"minicom" terminal emulation program for serial download. I (wd) 4408consider minicom to be broken, and recommend not to use it. Under 4409Unix, I recommend to use C-Kermit for general purpose use (and 4410especially for kermit binary protocol download ("loadb" command), and 4411use "cu" for S-Record download ("loads" command). 4412 4413Nevertheless, if you absolutely want to use it try adding this 4414configuration to your "File transfer protocols" section: 4415 4416 Name Program Name U/D FullScr IO-Red. Multi 4417 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 4418 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 4419 4420 4421NetBSD Notes: 4422============= 4423 4424Starting at version 0.9.2, U-Boot supports NetBSD both as host 4425(build U-Boot) and target system (boots NetBSD/mpc8xx). 4426 4427Building requires a cross environment; it is known to work on 4428NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 4429need gmake since the Makefiles are not compatible with BSD make). 4430Note that the cross-powerpc package does not install include files; 4431attempting to build U-Boot will fail because <machine/ansi.h> is 4432missing. This file has to be installed and patched manually: 4433 4434 # cd /usr/pkg/cross/powerpc-netbsd/include 4435 # mkdir powerpc 4436 # ln -s powerpc machine 4437 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 4438 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 4439 4440Native builds *don't* work due to incompatibilities between native 4441and U-Boot include files. 4442 4443Booting assumes that (the first part of) the image booted is a 4444stage-2 loader which in turn loads and then invokes the kernel 4445proper. Loader sources will eventually appear in the NetBSD source 4446tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 4447meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 4448 4449 4450Implementation Internals: 4451========================= 4452 4453The following is not intended to be a complete description of every 4454implementation detail. However, it should help to understand the 4455inner workings of U-Boot and make it easier to port it to custom 4456hardware. 4457 4458 4459Initial Stack, Global Data: 4460--------------------------- 4461 4462The implementation of U-Boot is complicated by the fact that U-Boot 4463starts running out of ROM (flash memory), usually without access to 4464system RAM (because the memory controller is not initialized yet). 4465This means that we don't have writable Data or BSS segments, and BSS 4466is not initialized as zero. To be able to get a C environment working 4467at all, we have to allocate at least a minimal stack. Implementation 4468options for this are defined and restricted by the CPU used: Some CPU 4469models provide on-chip memory (like the IMMR area on MPC8xx and 4470MPC826x processors), on others (parts of) the data cache can be 4471locked as (mis-) used as memory, etc. 4472 4473 Chris Hallinan posted a good summary of these issues to the 4474 U-Boot mailing list: 4475 4476 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 4477 From: "Chris Hallinan" <clh@net1plus.com> 4478 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 4479 ... 4480 4481 Correct me if I'm wrong, folks, but the way I understand it 4482 is this: Using DCACHE as initial RAM for Stack, etc, does not 4483 require any physical RAM backing up the cache. The cleverness 4484 is that the cache is being used as a temporary supply of 4485 necessary storage before the SDRAM controller is setup. It's 4486 beyond the scope of this list to explain the details, but you 4487 can see how this works by studying the cache architecture and 4488 operation in the architecture and processor-specific manuals. 4489 4490 OCM is On Chip Memory, which I believe the 405GP has 4K. It 4491 is another option for the system designer to use as an 4492 initial stack/RAM area prior to SDRAM being available. Either 4493 option should work for you. Using CS 4 should be fine if your 4494 board designers haven't used it for something that would 4495 cause you grief during the initial boot! It is frequently not 4496 used. 4497 4498 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 4499 with your processor/board/system design. The default value 4500 you will find in any recent u-boot distribution in 4501 walnut.h should work for you. I'd set it to a value larger 4502 than your SDRAM module. If you have a 64MB SDRAM module, set 4503 it above 400_0000. Just make sure your board has no resources 4504 that are supposed to respond to that address! That code in 4505 start.S has been around a while and should work as is when 4506 you get the config right. 4507 4508 -Chris Hallinan 4509 DS4.COM, Inc. 4510 4511It is essential to remember this, since it has some impact on the C 4512code for the initialization procedures: 4513 4514* Initialized global data (data segment) is read-only. Do not attempt 4515 to write it. 4516 4517* Do not use any uninitialized global data (or implicitely initialized 4518 as zero data - BSS segment) at all - this is undefined, initiali- 4519 zation is performed later (when relocating to RAM). 4520 4521* Stack space is very limited. Avoid big data buffers or things like 4522 that. 4523 4524Having only the stack as writable memory limits means we cannot use 4525normal global data to share information beween the code. But it 4526turned out that the implementation of U-Boot can be greatly 4527simplified by making a global data structure (gd_t) available to all 4528functions. We could pass a pointer to this data as argument to _all_ 4529functions, but this would bloat the code. Instead we use a feature of 4530the GCC compiler (Global Register Variables) to share the data: we 4531place a pointer (gd) to the global data into a register which we 4532reserve for this purpose. 4533 4534When choosing a register for such a purpose we are restricted by the 4535relevant (E)ABI specifications for the current architecture, and by 4536GCC's implementation. 4537 4538For PowerPC, the following registers have specific use: 4539 R1: stack pointer 4540 R2: reserved for system use 4541 R3-R4: parameter passing and return values 4542 R5-R10: parameter passing 4543 R13: small data area pointer 4544 R30: GOT pointer 4545 R31: frame pointer 4546 4547 (U-Boot also uses R12 as internal GOT pointer. r12 4548 is a volatile register so r12 needs to be reset when 4549 going back and forth between asm and C) 4550 4551 ==> U-Boot will use R2 to hold a pointer to the global data 4552 4553 Note: on PPC, we could use a static initializer (since the 4554 address of the global data structure is known at compile time), 4555 but it turned out that reserving a register results in somewhat 4556 smaller code - although the code savings are not that big (on 4557 average for all boards 752 bytes for the whole U-Boot image, 4558 624 text + 127 data). 4559 4560On Blackfin, the normal C ABI (except for P3) is followed as documented here: 4561 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 4562 4563 ==> U-Boot will use P3 to hold a pointer to the global data 4564 4565On ARM, the following registers are used: 4566 4567 R0: function argument word/integer result 4568 R1-R3: function argument word 4569 R9: GOT pointer 4570 R10: stack limit (used only if stack checking if enabled) 4571 R11: argument (frame) pointer 4572 R12: temporary workspace 4573 R13: stack pointer 4574 R14: link register 4575 R15: program counter 4576 4577 ==> U-Boot will use R8 to hold a pointer to the global data 4578 4579On Nios II, the ABI is documented here: 4580 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 4581 4582 ==> U-Boot will use gp to hold a pointer to the global data 4583 4584 Note: on Nios II, we give "-G0" option to gcc and don't use gp 4585 to access small data sections, so gp is free. 4586 4587On NDS32, the following registers are used: 4588 4589 R0-R1: argument/return 4590 R2-R5: argument 4591 R15: temporary register for assembler 4592 R16: trampoline register 4593 R28: frame pointer (FP) 4594 R29: global pointer (GP) 4595 R30: link register (LP) 4596 R31: stack pointer (SP) 4597 PC: program counter (PC) 4598 4599 ==> U-Boot will use R10 to hold a pointer to the global data 4600 4601NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 4602or current versions of GCC may "optimize" the code too much. 4603 4604Memory Management: 4605------------------ 4606 4607U-Boot runs in system state and uses physical addresses, i.e. the 4608MMU is not used either for address mapping nor for memory protection. 4609 4610The available memory is mapped to fixed addresses using the memory 4611controller. In this process, a contiguous block is formed for each 4612memory type (Flash, SDRAM, SRAM), even when it consists of several 4613physical memory banks. 4614 4615U-Boot is installed in the first 128 kB of the first Flash bank (on 4616TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 4617booting and sizing and initializing DRAM, the code relocates itself 4618to the upper end of DRAM. Immediately below the U-Boot code some 4619memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 4620configuration setting]. Below that, a structure with global Board 4621Info data is placed, followed by the stack (growing downward). 4622 4623Additionally, some exception handler code is copied to the low 8 kB 4624of DRAM (0x00000000 ... 0x00001FFF). 4625 4626So a typical memory configuration with 16 MB of DRAM could look like 4627this: 4628 4629 0x0000 0000 Exception Vector code 4630 : 4631 0x0000 1FFF 4632 0x0000 2000 Free for Application Use 4633 : 4634 : 4635 4636 : 4637 : 4638 0x00FB FF20 Monitor Stack (Growing downward) 4639 0x00FB FFAC Board Info Data and permanent copy of global data 4640 0x00FC 0000 Malloc Arena 4641 : 4642 0x00FD FFFF 4643 0x00FE 0000 RAM Copy of Monitor Code 4644 ... eventually: LCD or video framebuffer 4645 ... eventually: pRAM (Protected RAM - unchanged by reset) 4646 0x00FF FFFF [End of RAM] 4647 4648 4649System Initialization: 4650---------------------- 4651 4652In the reset configuration, U-Boot starts at the reset entry point 4653(on most PowerPC systems at address 0x00000100). Because of the reset 4654configuration for CS0# this is a mirror of the onboard Flash memory. 4655To be able to re-map memory U-Boot then jumps to its link address. 4656To be able to implement the initialization code in C, a (small!) 4657initial stack is set up in the internal Dual Ported RAM (in case CPUs 4658which provide such a feature like MPC8xx or MPC8260), or in a locked 4659part of the data cache. After that, U-Boot initializes the CPU core, 4660the caches and the SIU. 4661 4662Next, all (potentially) available memory banks are mapped using a 4663preliminary mapping. For example, we put them on 512 MB boundaries 4664(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 4665on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 4666programmed for SDRAM access. Using the temporary configuration, a 4667simple memory test is run that determines the size of the SDRAM 4668banks. 4669 4670When there is more than one SDRAM bank, and the banks are of 4671different size, the largest is mapped first. For equal size, the first 4672bank (CS2#) is mapped first. The first mapping is always for address 46730x00000000, with any additional banks following immediately to create 4674contiguous memory starting from 0. 4675 4676Then, the monitor installs itself at the upper end of the SDRAM area 4677and allocates memory for use by malloc() and for the global Board 4678Info data; also, the exception vector code is copied to the low RAM 4679pages, and the final stack is set up. 4680 4681Only after this relocation will you have a "normal" C environment; 4682until that you are restricted in several ways, mostly because you are 4683running from ROM, and because the code will have to be relocated to a 4684new address in RAM. 4685 4686 4687U-Boot Porting Guide: 4688---------------------- 4689 4690[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 4691list, October 2002] 4692 4693 4694int main(int argc, char *argv[]) 4695{ 4696 sighandler_t no_more_time; 4697 4698 signal(SIGALRM, no_more_time); 4699 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 4700 4701 if (available_money > available_manpower) { 4702 Pay consultant to port U-Boot; 4703 return 0; 4704 } 4705 4706 Download latest U-Boot source; 4707 4708 Subscribe to u-boot mailing list; 4709 4710 if (clueless) 4711 email("Hi, I am new to U-Boot, how do I get started?"); 4712 4713 while (learning) { 4714 Read the README file in the top level directory; 4715 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 4716 Read applicable doc/*.README; 4717 Read the source, Luke; 4718 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 4719 } 4720 4721 if (available_money > toLocalCurrency ($2500)) 4722 Buy a BDI3000; 4723 else 4724 Add a lot of aggravation and time; 4725 4726 if (a similar board exists) { /* hopefully... */ 4727 cp -a board/<similar> board/<myboard> 4728 cp include/configs/<similar>.h include/configs/<myboard>.h 4729 } else { 4730 Create your own board support subdirectory; 4731 Create your own board include/configs/<myboard>.h file; 4732 } 4733 Edit new board/<myboard> files 4734 Edit new include/configs/<myboard>.h 4735 4736 while (!accepted) { 4737 while (!running) { 4738 do { 4739 Add / modify source code; 4740 } until (compiles); 4741 Debug; 4742 if (clueless) 4743 email("Hi, I am having problems..."); 4744 } 4745 Send patch file to the U-Boot email list; 4746 if (reasonable critiques) 4747 Incorporate improvements from email list code review; 4748 else 4749 Defend code as written; 4750 } 4751 4752 return 0; 4753} 4754 4755void no_more_time (int sig) 4756{ 4757 hire_a_guru(); 4758} 4759 4760 4761Coding Standards: 4762----------------- 4763 4764All contributions to U-Boot should conform to the Linux kernel 4765coding style; see the file "Documentation/CodingStyle" and the script 4766"scripts/Lindent" in your Linux kernel source directory. 4767 4768Source files originating from a different project (for example the 4769MTD subsystem) are generally exempt from these guidelines and are not 4770reformated to ease subsequent migration to newer versions of those 4771sources. 4772 4773Please note that U-Boot is implemented in C (and to some small parts in 4774Assembler); no C++ is used, so please do not use C++ style comments (//) 4775in your code. 4776 4777Please also stick to the following formatting rules: 4778- remove any trailing white space 4779- use TAB characters for indentation and vertical alignment, not spaces 4780- make sure NOT to use DOS '\r\n' line feeds 4781- do not add more than 2 consecutive empty lines to source files 4782- do not add trailing empty lines to source files 4783 4784Submissions which do not conform to the standards may be returned 4785with a request to reformat the changes. 4786 4787 4788Submitting Patches: 4789------------------- 4790 4791Since the number of patches for U-Boot is growing, we need to 4792establish some rules. Submissions which do not conform to these rules 4793may be rejected, even when they contain important and valuable stuff. 4794 4795Please see http://www.denx.de/wiki/U-Boot/Patches for details. 4796 4797Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 4798see http://lists.denx.de/mailman/listinfo/u-boot 4799 4800When you send a patch, please include the following information with 4801it: 4802 4803* For bug fixes: a description of the bug and how your patch fixes 4804 this bug. Please try to include a way of demonstrating that the 4805 patch actually fixes something. 4806 4807* For new features: a description of the feature and your 4808 implementation. 4809 4810* A CHANGELOG entry as plaintext (separate from the patch) 4811 4812* For major contributions, your entry to the CREDITS file 4813 4814* When you add support for a new board, don't forget to add this 4815 board to the MAINTAINERS file, too. 4816 4817* If your patch adds new configuration options, don't forget to 4818 document these in the README file. 4819 4820* The patch itself. If you are using git (which is *strongly* 4821 recommended) you can easily generate the patch using the 4822 "git format-patch". If you then use "git send-email" to send it to 4823 the U-Boot mailing list, you will avoid most of the common problems 4824 with some other mail clients. 4825 4826 If you cannot use git, use "diff -purN OLD NEW". If your version of 4827 diff does not support these options, then get the latest version of 4828 GNU diff. 4829 4830 The current directory when running this command shall be the parent 4831 directory of the U-Boot source tree (i. e. please make sure that 4832 your patch includes sufficient directory information for the 4833 affected files). 4834 4835 We prefer patches as plain text. MIME attachments are discouraged, 4836 and compressed attachments must not be used. 4837 4838* If one logical set of modifications affects or creates several 4839 files, all these changes shall be submitted in a SINGLE patch file. 4840 4841* Changesets that contain different, unrelated modifications shall be 4842 submitted as SEPARATE patches, one patch per changeset. 4843 4844 4845Notes: 4846 4847* Before sending the patch, run the MAKEALL script on your patched 4848 source tree and make sure that no errors or warnings are reported 4849 for any of the boards. 4850 4851* Keep your modifications to the necessary minimum: A patch 4852 containing several unrelated changes or arbitrary reformats will be 4853 returned with a request to re-formatting / split it. 4854 4855* If you modify existing code, make sure that your new code does not 4856 add to the memory footprint of the code ;-) Small is beautiful! 4857 When adding new features, these should compile conditionally only 4858 (using #ifdef), and the resulting code with the new feature 4859 disabled must not need more memory than the old code without your 4860 modification. 4861 4862* Remember that there is a size limit of 100 kB per message on the 4863 u-boot mailing list. Bigger patches will be moderated. If they are 4864 reasonable and not too big, they will be acknowledged. But patches 4865 bigger than the size limit should be avoided. 4866