1# 2# (C) Copyright 2000 - 2012 3# Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4# 5# See file CREDITS for list of people who contributed to this 6# project. 7# 8# This program is free software; you can redistribute it and/or 9# modify it under the terms of the GNU General Public License as 10# published by the Free Software Foundation; either version 2 of 11# the License, or (at your option) any later version. 12# 13# This program is distributed in the hope that it will be useful, 14# but WITHOUT ANY WARRANTY; without even the implied warranty of 15# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16# GNU General Public License for more details. 17# 18# You should have received a copy of the GNU General Public License 19# along with this program; if not, write to the Free Software 20# Foundation, Inc., 59 Temple Place, Suite 330, Boston, 21# MA 02111-1307 USA 22# 23 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 57Note: There is no CHANGELOG file in the actual U-Boot source tree; 58it can be created dynamically from the Git log using: 59 60 make CHANGELOG 61 62 63Where to get help: 64================== 65 66In case you have questions about, problems with or contributions for 67U-Boot you should send a message to the U-Boot mailing list at 68<u-boot@lists.denx.de>. There is also an archive of previous traffic 69on the mailing list - please search the archive before asking FAQ's. 70Please see http://lists.denx.de/pipermail/u-boot and 71http://dir.gmane.org/gmane.comp.boot-loaders.u-boot 72 73 74Where to get source code: 75========================= 76 77The U-Boot source code is maintained in the git repository at 78git://www.denx.de/git/u-boot.git ; you can browse it online at 79http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary 80 81The "snapshot" links on this page allow you to download tarballs of 82any version you might be interested in. Official releases are also 83available for FTP download from the ftp://ftp.denx.de/pub/u-boot/ 84directory. 85 86Pre-built (and tested) images are available from 87ftp://ftp.denx.de/pub/u-boot/images/ 88 89 90Where we come from: 91=================== 92 93- start from 8xxrom sources 94- create PPCBoot project (http://sourceforge.net/projects/ppcboot) 95- clean up code 96- make it easier to add custom boards 97- make it possible to add other [PowerPC] CPUs 98- extend functions, especially: 99 * Provide extended interface to Linux boot loader 100 * S-Record download 101 * network boot 102 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot 103- create ARMBoot project (http://sourceforge.net/projects/armboot) 104- add other CPU families (starting with ARM) 105- create U-Boot project (http://sourceforge.net/projects/u-boot) 106- current project page: see http://www.denx.de/wiki/U-Boot 107 108 109Names and Spelling: 110=================== 111 112The "official" name of this project is "Das U-Boot". The spelling 113"U-Boot" shall be used in all written text (documentation, comments 114in source files etc.). Example: 115 116 This is the README file for the U-Boot project. 117 118File names etc. shall be based on the string "u-boot". Examples: 119 120 include/asm-ppc/u-boot.h 121 122 #include <asm/u-boot.h> 123 124Variable names, preprocessor constants etc. shall be either based on 125the string "u_boot" or on "U_BOOT". Example: 126 127 U_BOOT_VERSION u_boot_logo 128 IH_OS_U_BOOT u_boot_hush_start 129 130 131Versioning: 132=========== 133 134Starting with the release in October 2008, the names of the releases 135were changed from numerical release numbers without deeper meaning 136into a time stamp based numbering. Regular releases are identified by 137names consisting of the calendar year and month of the release date. 138Additional fields (if present) indicate release candidates or bug fix 139releases in "stable" maintenance trees. 140 141Examples: 142 U-Boot v2009.11 - Release November 2009 143 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree 144 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release 145 146 147Directory Hierarchy: 148==================== 149 150/arch Architecture specific files 151 /arm Files generic to ARM architecture 152 /cpu CPU specific files 153 /arm720t Files specific to ARM 720 CPUs 154 /arm920t Files specific to ARM 920 CPUs 155 /at91 Files specific to Atmel AT91RM9200 CPU 156 /imx Files specific to Freescale MC9328 i.MX CPUs 157 /s3c24x0 Files specific to Samsung S3C24X0 CPUs 158 /arm925t Files specific to ARM 925 CPUs 159 /arm926ejs Files specific to ARM 926 CPUs 160 /arm1136 Files specific to ARM 1136 CPUs 161 /ixp Files specific to Intel XScale IXP CPUs 162 /pxa Files specific to Intel XScale PXA CPUs 163 /s3c44b0 Files specific to Samsung S3C44B0 CPUs 164 /sa1100 Files specific to Intel StrongARM SA1100 CPUs 165 /lib Architecture specific library files 166 /avr32 Files generic to AVR32 architecture 167 /cpu CPU specific files 168 /lib Architecture specific library files 169 /blackfin Files generic to Analog Devices Blackfin architecture 170 /cpu CPU specific files 171 /lib Architecture specific library files 172 /x86 Files generic to x86 architecture 173 /cpu CPU specific files 174 /lib Architecture specific library files 175 /m68k Files generic to m68k architecture 176 /cpu CPU specific files 177 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs 178 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs 179 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs 180 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs 181 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs 182 /lib Architecture specific library files 183 /microblaze Files generic to microblaze architecture 184 /cpu CPU specific files 185 /lib Architecture specific library files 186 /mips Files generic to MIPS architecture 187 /cpu CPU specific files 188 /mips32 Files specific to MIPS32 CPUs 189 /xburst Files specific to Ingenic XBurst CPUs 190 /lib Architecture specific library files 191 /nds32 Files generic to NDS32 architecture 192 /cpu CPU specific files 193 /n1213 Files specific to Andes Technology N1213 CPUs 194 /lib Architecture specific library files 195 /nios2 Files generic to Altera NIOS2 architecture 196 /cpu CPU specific files 197 /lib Architecture specific library files 198 /powerpc Files generic to PowerPC architecture 199 /cpu CPU specific files 200 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs 201 /mpc5xx Files specific to Freescale MPC5xx CPUs 202 /mpc5xxx Files specific to Freescale MPC5xxx CPUs 203 /mpc8xx Files specific to Freescale MPC8xx CPUs 204 /mpc8220 Files specific to Freescale MPC8220 CPUs 205 /mpc824x Files specific to Freescale MPC824x CPUs 206 /mpc8260 Files specific to Freescale MPC8260 CPUs 207 /mpc85xx Files specific to Freescale MPC85xx CPUs 208 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs 209 /lib Architecture specific library files 210 /sh Files generic to SH architecture 211 /cpu CPU specific files 212 /sh2 Files specific to sh2 CPUs 213 /sh3 Files specific to sh3 CPUs 214 /sh4 Files specific to sh4 CPUs 215 /lib Architecture specific library files 216 /sparc Files generic to SPARC architecture 217 /cpu CPU specific files 218 /leon2 Files specific to Gaisler LEON2 SPARC CPU 219 /leon3 Files specific to Gaisler LEON3 SPARC CPU 220 /lib Architecture specific library files 221/api Machine/arch independent API for external apps 222/board Board dependent files 223/common Misc architecture independent functions 224/disk Code for disk drive partition handling 225/doc Documentation (don't expect too much) 226/drivers Commonly used device drivers 227/examples Example code for standalone applications, etc. 228/fs Filesystem code (cramfs, ext2, jffs2, etc.) 229/include Header Files 230/lib Files generic to all architectures 231 /libfdt Library files to support flattened device trees 232 /lzma Library files to support LZMA decompression 233 /lzo Library files to support LZO decompression 234/net Networking code 235/post Power On Self Test 236/rtc Real Time Clock drivers 237/tools Tools to build S-Record or U-Boot images, etc. 238 239Software Configuration: 240======================= 241 242Configuration is usually done using C preprocessor defines; the 243rationale behind that is to avoid dead code whenever possible. 244 245There are two classes of configuration variables: 246 247* Configuration _OPTIONS_: 248 These are selectable by the user and have names beginning with 249 "CONFIG_". 250 251* Configuration _SETTINGS_: 252 These depend on the hardware etc. and should not be meddled with if 253 you don't know what you're doing; they have names beginning with 254 "CONFIG_SYS_". 255 256Later we will add a configuration tool - probably similar to or even 257identical to what's used for the Linux kernel. Right now, we have to 258do the configuration by hand, which means creating some symbolic 259links and editing some configuration files. We use the TQM8xxL boards 260as an example here. 261 262 263Selection of Processor Architecture and Board Type: 264--------------------------------------------------- 265 266For all supported boards there are ready-to-use default 267configurations available; just type "make <board_name>_config". 268 269Example: For a TQM823L module type: 270 271 cd u-boot 272 make TQM823L_config 273 274For the Cogent platform, you need to specify the CPU type as well; 275e.g. "make cogent_mpc8xx_config". And also configure the cogent 276directory according to the instructions in cogent/README. 277 278 279Configuration Options: 280---------------------- 281 282Configuration depends on the combination of board and CPU type; all 283such information is kept in a configuration file 284"include/configs/<board_name>.h". 285 286Example: For a TQM823L module, all configuration settings are in 287"include/configs/TQM823L.h". 288 289 290Many of the options are named exactly as the corresponding Linux 291kernel configuration options. The intention is to make it easier to 292build a config tool - later. 293 294 295The following options need to be configured: 296 297- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 298 299- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 300 301- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 302 Define exactly one, e.g. CONFIG_ATSTK1002 303 304- CPU Module Type: (if CONFIG_COGENT is defined) 305 Define exactly one of 306 CONFIG_CMA286_60_OLD 307--- FIXME --- not tested yet: 308 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P, 309 CONFIG_CMA287_23, CONFIG_CMA287_50 310 311- Motherboard Type: (if CONFIG_COGENT is defined) 312 Define exactly one of 313 CONFIG_CMA101, CONFIG_CMA102 314 315- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 316 Define one or more of 317 CONFIG_CMA302 318 319- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined) 320 Define one or more of 321 CONFIG_LCD_HEARTBEAT - update a character position on 322 the LCD display every second with 323 a "rotator" |\-/|\-/ 324 325- Board flavour: (if CONFIG_MPC8260ADS is defined) 326 CONFIG_ADSTYPE 327 Possible values are: 328 CONFIG_SYS_8260ADS - original MPC8260ADS 329 CONFIG_SYS_8266ADS - MPC8266ADS 330 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR 331 CONFIG_SYS_8272ADS - MPC8272ADS 332 333- Marvell Family Member 334 CONFIG_SYS_MVFS - define it if you want to enable 335 multiple fs option at one time 336 for marvell soc family 337 338- MPC824X Family Member (if CONFIG_MPC824X is defined) 339 Define exactly one of 340 CONFIG_MPC8240, CONFIG_MPC8245 341 342- 8xx CPU Options: (if using an MPC8xx CPU) 343 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 344 get_gclk_freq() cannot work 345 e.g. if there is no 32KHz 346 reference PIT/RTC clock 347 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 348 or XTAL/EXTAL) 349 350- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 351 CONFIG_SYS_8xx_CPUCLK_MIN 352 CONFIG_SYS_8xx_CPUCLK_MAX 353 CONFIG_8xx_CPUCLK_DEFAULT 354 See doc/README.MPC866 355 356 CONFIG_SYS_MEASURE_CPUCLK 357 358 Define this to measure the actual CPU clock instead 359 of relying on the correctness of the configured 360 values. Mostly useful for board bringup to make sure 361 the PLL is locked at the intended frequency. Note 362 that this requires a (stable) reference clock (32 kHz 363 RTC clock or CONFIG_SYS_8XX_XIN) 364 365 CONFIG_SYS_DELAYED_ICACHE 366 367 Define this option if you want to enable the 368 ICache only when Code runs from RAM. 369 370- 85xx CPU Options: 371 CONFIG_SYS_PPC64 372 373 Specifies that the core is a 64-bit PowerPC implementation (implements 374 the "64" category of the Power ISA). This is necessary for ePAPR 375 compliance, among other possible reasons. 376 377 CONFIG_SYS_FSL_TBCLK_DIV 378 379 Defines the core time base clock divider ratio compared to the 380 system clock. On most PQ3 devices this is 8, on newer QorIQ 381 devices it can be 16 or 32. The ratio varies from SoC to Soc. 382 383 CONFIG_SYS_FSL_PCIE_COMPAT 384 385 Defines the string to utilize when trying to match PCIe device 386 tree nodes for the given platform. 387 388 CONFIG_SYS_PPC_E500_DEBUG_TLB 389 390 Enables a temporary TLB entry to be used during boot to work 391 around limitations in e500v1 and e500v2 external debugger 392 support. This reduces the portions of the boot code where 393 breakpoints and single stepping do not work. The value of this 394 symbol should be set to the TLB1 entry to be used for this 395 purpose. 396 397 CONFIG_SYS_FSL_ERRATUM_A004510 398 399 Enables a workaround for erratum A004510. If set, 400 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and 401 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set. 402 403 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV 404 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional) 405 406 Defines one or two SoC revisions (low 8 bits of SVR) 407 for which the A004510 workaround should be applied. 408 409 The rest of SVR is either not relevant to the decision 410 of whether the erratum is present (e.g. p2040 versus 411 p2041) or is implied by the build target, which controls 412 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set. 413 414 See Freescale App Note 4493 for more information about 415 this erratum. 416 417 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 418 419 This is the value to write into CCSR offset 0x18600 420 according to the A004510 workaround. 421 422- Generic CPU options: 423 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN 424 425 Defines the endianess of the CPU. Implementation of those 426 values is arch specific. 427 428- Intel Monahans options: 429 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO 430 431 Defines the Monahans run mode to oscillator 432 ratio. Valid values are 8, 16, 24, 31. The core 433 frequency is this value multiplied by 13 MHz. 434 435 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO 436 437 Defines the Monahans turbo mode to oscillator 438 ratio. Valid values are 1 (default if undefined) and 439 2. The core frequency as calculated above is multiplied 440 by this value. 441 442- MIPS CPU options: 443 CONFIG_SYS_INIT_SP_OFFSET 444 445 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack 446 pointer. This is needed for the temporary stack before 447 relocation. 448 449 CONFIG_SYS_MIPS_CACHE_MODE 450 451 Cache operation mode for the MIPS CPU. 452 See also arch/mips/include/asm/mipsregs.h. 453 Possible values are: 454 CONF_CM_CACHABLE_NO_WA 455 CONF_CM_CACHABLE_WA 456 CONF_CM_UNCACHED 457 CONF_CM_CACHABLE_NONCOHERENT 458 CONF_CM_CACHABLE_CE 459 CONF_CM_CACHABLE_COW 460 CONF_CM_CACHABLE_CUW 461 CONF_CM_CACHABLE_ACCELERATED 462 463 CONFIG_SYS_XWAY_EBU_BOOTCFG 464 465 Special option for Lantiq XWAY SoCs for booting from NOR flash. 466 See also arch/mips/cpu/mips32/start.S. 467 468 CONFIG_XWAY_SWAP_BYTES 469 470 Enable compilation of tools/xway-swap-bytes needed for Lantiq 471 XWAY SoCs for booting from NOR flash. The U-Boot image needs to 472 be swapped if a flash programmer is used. 473 474- ARM options: 475 CONFIG_SYS_EXCEPTION_VECTORS_HIGH 476 477 Select high exception vectors of the ARM core, e.g., do not 478 clear the V bit of the c1 register of CP15. 479 480 CONFIG_SYS_THUMB_BUILD 481 482 Use this flag to build U-Boot using the Thumb instruction 483 set for ARM architectures. Thumb instruction set provides 484 better code density. For ARM architectures that support 485 Thumb2 this flag will result in Thumb2 code generated by 486 GCC. 487 488- Linux Kernel Interface: 489 CONFIG_CLOCKS_IN_MHZ 490 491 U-Boot stores all clock information in Hz 492 internally. For binary compatibility with older Linux 493 kernels (which expect the clocks passed in the 494 bd_info data to be in MHz) the environment variable 495 "clocks_in_mhz" can be defined so that U-Boot 496 converts clock data to MHZ before passing it to the 497 Linux kernel. 498 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 499 "clocks_in_mhz=1" is automatically included in the 500 default environment. 501 502 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 503 504 When transferring memsize parameter to linux, some versions 505 expect it to be in bytes, others in MB. 506 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 507 508 CONFIG_OF_LIBFDT 509 510 New kernel versions are expecting firmware settings to be 511 passed using flattened device trees (based on open firmware 512 concepts). 513 514 CONFIG_OF_LIBFDT 515 * New libfdt-based support 516 * Adds the "fdt" command 517 * The bootm command automatically updates the fdt 518 519 OF_CPU - The proper name of the cpus node (only required for 520 MPC512X and MPC5xxx based boards). 521 OF_SOC - The proper name of the soc node (only required for 522 MPC512X and MPC5xxx based boards). 523 OF_TBCLK - The timebase frequency. 524 OF_STDOUT_PATH - The path to the console device 525 526 boards with QUICC Engines require OF_QE to set UCC MAC 527 addresses 528 529 CONFIG_OF_BOARD_SETUP 530 531 Board code has addition modification that it wants to make 532 to the flat device tree before handing it off to the kernel 533 534 CONFIG_OF_BOOT_CPU 535 536 This define fills in the correct boot CPU in the boot 537 param header, the default value is zero if undefined. 538 539 CONFIG_OF_IDE_FIXUP 540 541 U-Boot can detect if an IDE device is present or not. 542 If not, and this new config option is activated, U-Boot 543 removes the ATA node from the DTS before booting Linux, 544 so the Linux IDE driver does not probe the device and 545 crash. This is needed for buggy hardware (uc101) where 546 no pull down resistor is connected to the signal IDE5V_DD7. 547 548 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 549 550 This setting is mandatory for all boards that have only one 551 machine type and must be used to specify the machine type 552 number as it appears in the ARM machine registry 553 (see http://www.arm.linux.org.uk/developer/machines/). 554 Only boards that have multiple machine types supported 555 in a single configuration file and the machine type is 556 runtime discoverable, do not have to use this setting. 557 558- vxWorks boot parameters: 559 560 bootvx constructs a valid bootline using the following 561 environments variables: bootfile, ipaddr, serverip, hostname. 562 It loads the vxWorks image pointed bootfile. 563 564 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name 565 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address 566 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server 567 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters 568 569 CONFIG_SYS_VXWORKS_ADD_PARAMS 570 571 Add it at the end of the bootline. E.g "u=username pw=secret" 572 573 Note: If a "bootargs" environment is defined, it will overwride 574 the defaults discussed just above. 575 576- Cache Configuration: 577 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 578 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 579 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 580 581- Cache Configuration for ARM: 582 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 583 controller 584 CONFIG_SYS_PL310_BASE - Physical base address of PL310 585 controller register space 586 587- Serial Ports: 588 CONFIG_PL010_SERIAL 589 590 Define this if you want support for Amba PrimeCell PL010 UARTs. 591 592 CONFIG_PL011_SERIAL 593 594 Define this if you want support for Amba PrimeCell PL011 UARTs. 595 596 CONFIG_PL011_CLOCK 597 598 If you have Amba PrimeCell PL011 UARTs, set this variable to 599 the clock speed of the UARTs. 600 601 CONFIG_PL01x_PORTS 602 603 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 604 define this to a list of base addresses for each (supported) 605 port. See e.g. include/configs/versatile.h 606 607 CONFIG_PL011_SERIAL_RLCR 608 609 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500) 610 have separate receive and transmit line control registers. Set 611 this variable to initialize the extra register. 612 613 CONFIG_PL011_SERIAL_FLUSH_ON_INIT 614 615 On some platforms (e.g. U8500) U-Boot is loaded by a second stage 616 boot loader that has already initialized the UART. Define this 617 variable to flush the UART at init time. 618 619 CONFIG_SYS_NS16550_BROKEN_TEMT 620 621 16550 UART set the Transmitter Empty (TEMT) Bit when all output 622 has finished and the transmitter is totally empty. U-Boot waits 623 for this bit to be set to initialize the serial console. On some 624 broken platforms this bit is not set in SPL making U-Boot to 625 hang while waiting for TEMT. Define this option to avoid it. 626 627 628- Console Interface: 629 Depending on board, define exactly one serial port 630 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 631 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 632 console by defining CONFIG_8xx_CONS_NONE 633 634 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 635 port routines must be defined elsewhere 636 (i.e. serial_init(), serial_getc(), ...) 637 638 CONFIG_CFB_CONSOLE 639 Enables console device for a color framebuffer. Needs following 640 defines (cf. smiLynxEM, i8042) 641 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 642 (default big endian) 643 VIDEO_HW_RECTFILL graphic chip supports 644 rectangle fill 645 (cf. smiLynxEM) 646 VIDEO_HW_BITBLT graphic chip supports 647 bit-blit (cf. smiLynxEM) 648 VIDEO_VISIBLE_COLS visible pixel columns 649 (cols=pitch) 650 VIDEO_VISIBLE_ROWS visible pixel rows 651 VIDEO_PIXEL_SIZE bytes per pixel 652 VIDEO_DATA_FORMAT graphic data format 653 (0-5, cf. cfb_console.c) 654 VIDEO_FB_ADRS framebuffer address 655 VIDEO_KBD_INIT_FCT keyboard int fct 656 (i.e. i8042_kbd_init()) 657 VIDEO_TSTC_FCT test char fct 658 (i.e. i8042_tstc) 659 VIDEO_GETC_FCT get char fct 660 (i.e. i8042_getc) 661 CONFIG_CONSOLE_CURSOR cursor drawing on/off 662 (requires blink timer 663 cf. i8042.c) 664 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 665 CONFIG_CONSOLE_TIME display time/date info in 666 upper right corner 667 (requires CONFIG_CMD_DATE) 668 CONFIG_VIDEO_LOGO display Linux logo in 669 upper left corner 670 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 671 linux_logo.h for logo. 672 Requires CONFIG_VIDEO_LOGO 673 CONFIG_CONSOLE_EXTRA_INFO 674 additional board info beside 675 the logo 676 677 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support 678 a limited number of ANSI escape sequences (cursor control, 679 erase functions and limited graphics rendition control). 680 681 When CONFIG_CFB_CONSOLE is defined, video console is 682 default i/o. Serial console can be forced with 683 environment 'console=serial'. 684 685 When CONFIG_SILENT_CONSOLE is defined, all console 686 messages (by U-Boot and Linux!) can be silenced with 687 the "silent" environment variable. See 688 doc/README.silent for more information. 689 690- Console Baudrate: 691 CONFIG_BAUDRATE - in bps 692 Select one of the baudrates listed in 693 CONFIG_SYS_BAUDRATE_TABLE, see below. 694 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 695 696- Console Rx buffer length 697 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 698 the maximum receive buffer length for the SMC. 699 This option is actual only for 82xx and 8xx possible. 700 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 701 must be defined, to setup the maximum idle timeout for 702 the SMC. 703 704- Pre-Console Buffer: 705 Prior to the console being initialised (i.e. serial UART 706 initialised etc) all console output is silently discarded. 707 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to 708 buffer any console messages prior to the console being 709 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ 710 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is 711 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ 712 bytes are output before the console is initialised, the 713 earlier bytes are discarded. 714 715 'Sane' compilers will generate smaller code if 716 CONFIG_PRE_CON_BUF_SZ is a power of 2 717 718- Safe printf() functions 719 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of 720 the printf() functions. These are defined in 721 include/vsprintf.h and include snprintf(), vsnprintf() and 722 so on. Code size increase is approximately 300-500 bytes. 723 If this option is not given then these functions will 724 silently discard their buffer size argument - this means 725 you are not getting any overflow checking in this case. 726 727- Boot Delay: CONFIG_BOOTDELAY - in seconds 728 Delay before automatically booting the default image; 729 set to -1 to disable autoboot. 730 set to -2 to autoboot with no delay and not check for abort 731 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined). 732 733 See doc/README.autoboot for these options that 734 work with CONFIG_BOOTDELAY. None are required. 735 CONFIG_BOOT_RETRY_TIME 736 CONFIG_BOOT_RETRY_MIN 737 CONFIG_AUTOBOOT_KEYED 738 CONFIG_AUTOBOOT_PROMPT 739 CONFIG_AUTOBOOT_DELAY_STR 740 CONFIG_AUTOBOOT_STOP_STR 741 CONFIG_AUTOBOOT_DELAY_STR2 742 CONFIG_AUTOBOOT_STOP_STR2 743 CONFIG_ZERO_BOOTDELAY_CHECK 744 CONFIG_RESET_TO_RETRY 745 746- Autoboot Command: 747 CONFIG_BOOTCOMMAND 748 Only needed when CONFIG_BOOTDELAY is enabled; 749 define a command string that is automatically executed 750 when no character is read on the console interface 751 within "Boot Delay" after reset. 752 753 CONFIG_BOOTARGS 754 This can be used to pass arguments to the bootm 755 command. The value of CONFIG_BOOTARGS goes into the 756 environment value "bootargs". 757 758 CONFIG_RAMBOOT and CONFIG_NFSBOOT 759 The value of these goes into the environment as 760 "ramboot" and "nfsboot" respectively, and can be used 761 as a convenience, when switching between booting from 762 RAM and NFS. 763 764- Pre-Boot Commands: 765 CONFIG_PREBOOT 766 767 When this option is #defined, the existence of the 768 environment variable "preboot" will be checked 769 immediately before starting the CONFIG_BOOTDELAY 770 countdown and/or running the auto-boot command resp. 771 entering interactive mode. 772 773 This feature is especially useful when "preboot" is 774 automatically generated or modified. For an example 775 see the LWMON board specific code: here "preboot" is 776 modified when the user holds down a certain 777 combination of keys on the (special) keyboard when 778 booting the systems 779 780- Serial Download Echo Mode: 781 CONFIG_LOADS_ECHO 782 If defined to 1, all characters received during a 783 serial download (using the "loads" command) are 784 echoed back. This might be needed by some terminal 785 emulations (like "cu"), but may as well just take 786 time on others. This setting #define's the initial 787 value of the "loads_echo" environment variable. 788 789- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 790 CONFIG_KGDB_BAUDRATE 791 Select one of the baudrates listed in 792 CONFIG_SYS_BAUDRATE_TABLE, see below. 793 794- Monitor Functions: 795 Monitor commands can be included or excluded 796 from the build by using the #include files 797 <config_cmd_all.h> and #undef'ing unwanted 798 commands, or using <config_cmd_default.h> 799 and augmenting with additional #define's 800 for wanted commands. 801 802 The default command configuration includes all commands 803 except those marked below with a "*". 804 805 CONFIG_CMD_ASKENV * ask for env variable 806 CONFIG_CMD_BDI bdinfo 807 CONFIG_CMD_BEDBUG * Include BedBug Debugger 808 CONFIG_CMD_BMP * BMP support 809 CONFIG_CMD_BSP * Board specific commands 810 CONFIG_CMD_BOOTD bootd 811 CONFIG_CMD_CACHE * icache, dcache 812 CONFIG_CMD_CONSOLE coninfo 813 CONFIG_CMD_CRC32 * crc32 814 CONFIG_CMD_DATE * support for RTC, date/time... 815 CONFIG_CMD_DHCP * DHCP support 816 CONFIG_CMD_DIAG * Diagnostics 817 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands 818 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command 819 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd 820 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command 821 CONFIG_CMD_DTT * Digital Therm and Thermostat 822 CONFIG_CMD_ECHO echo arguments 823 CONFIG_CMD_EDITENV edit env variable 824 CONFIG_CMD_EEPROM * EEPROM read/write support 825 CONFIG_CMD_ELF * bootelf, bootvx 826 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks 827 CONFIG_CMD_ENV_FLAGS * display details about env flags 828 CONFIG_CMD_EXPORTENV * export the environment 829 CONFIG_CMD_EXT2 * ext2 command support 830 CONFIG_CMD_EXT4 * ext4 command support 831 CONFIG_CMD_SAVEENV saveenv 832 CONFIG_CMD_FDC * Floppy Disk Support 833 CONFIG_CMD_FAT * FAT command support 834 CONFIG_CMD_FDOS * Dos diskette Support 835 CONFIG_CMD_FLASH flinfo, erase, protect 836 CONFIG_CMD_FPGA FPGA device initialization support 837 CONFIG_CMD_GETTIME * Get time since boot 838 CONFIG_CMD_GO * the 'go' command (exec code) 839 CONFIG_CMD_GREPENV * search environment 840 CONFIG_CMD_HASH * calculate hash / digest 841 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control 842 CONFIG_CMD_I2C * I2C serial bus support 843 CONFIG_CMD_IDE * IDE harddisk support 844 CONFIG_CMD_IMI iminfo 845 CONFIG_CMD_IMLS List all images found in NOR flash 846 CONFIG_CMD_IMLS_NAND List all images found in NAND flash 847 CONFIG_CMD_IMMAP * IMMR dump support 848 CONFIG_CMD_IMPORTENV * import an environment 849 CONFIG_CMD_INI * import data from an ini file into the env 850 CONFIG_CMD_IRQ * irqinfo 851 CONFIG_CMD_ITEST Integer/string test of 2 values 852 CONFIG_CMD_JFFS2 * JFFS2 Support 853 CONFIG_CMD_KGDB * kgdb 854 CONFIG_CMD_LDRINFO ldrinfo (display Blackfin loader) 855 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration 856 (169.254.*.*) 857 CONFIG_CMD_LOADB loadb 858 CONFIG_CMD_LOADS loads 859 CONFIG_CMD_MD5SUM print md5 message digest 860 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 861 CONFIG_CMD_MEMINFO * Display detailed memory information 862 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 863 loop, loopw, mtest 864 CONFIG_CMD_MISC Misc functions like sleep etc 865 CONFIG_CMD_MMC * MMC memory mapped support 866 CONFIG_CMD_MII * MII utility commands 867 CONFIG_CMD_MTDPARTS * MTD partition support 868 CONFIG_CMD_NAND * NAND support 869 CONFIG_CMD_NET bootp, tftpboot, rarpboot 870 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 871 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 872 CONFIG_CMD_PCI * pciinfo 873 CONFIG_CMD_PCMCIA * PCMCIA support 874 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 875 host 876 CONFIG_CMD_PORTIO * Port I/O 877 CONFIG_CMD_READ * Read raw data from partition 878 CONFIG_CMD_REGINFO * Register dump 879 CONFIG_CMD_RUN run command in env variable 880 CONFIG_CMD_SAVES * save S record dump 881 CONFIG_CMD_SCSI * SCSI Support 882 CONFIG_CMD_SDRAM * print SDRAM configuration information 883 (requires CONFIG_CMD_I2C) 884 CONFIG_CMD_SETGETDCR Support for DCR Register access 885 (4xx only) 886 CONFIG_CMD_SF * Read/write/erase SPI NOR flash 887 CONFIG_CMD_SHA1SUM print sha1 memory digest 888 (requires CONFIG_CMD_MEMORY) 889 CONFIG_CMD_SOURCE "source" command Support 890 CONFIG_CMD_SPI * SPI serial bus support 891 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 892 CONFIG_CMD_TFTPPUT * TFTP put command (upload) 893 CONFIG_CMD_TIME * run command and report execution time (ARM specific) 894 CONFIG_CMD_TIMER * access to the system tick timer 895 CONFIG_CMD_USB * USB support 896 CONFIG_CMD_CDP * Cisco Discover Protocol support 897 CONFIG_CMD_MFSL * Microblaze FSL support 898 899 900 EXAMPLE: If you want all functions except of network 901 support you can write: 902 903 #include "config_cmd_all.h" 904 #undef CONFIG_CMD_NET 905 906 Other Commands: 907 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 908 909 Note: Don't enable the "icache" and "dcache" commands 910 (configuration option CONFIG_CMD_CACHE) unless you know 911 what you (and your U-Boot users) are doing. Data 912 cache cannot be enabled on systems like the 8xx or 913 8260 (where accesses to the IMMR region must be 914 uncached), and it cannot be disabled on all other 915 systems where we (mis-) use the data cache to hold an 916 initial stack and some data. 917 918 919 XXX - this list needs to get updated! 920 921- Device tree: 922 CONFIG_OF_CONTROL 923 If this variable is defined, U-Boot will use a device tree 924 to configure its devices, instead of relying on statically 925 compiled #defines in the board file. This option is 926 experimental and only available on a few boards. The device 927 tree is available in the global data as gd->fdt_blob. 928 929 U-Boot needs to get its device tree from somewhere. This can 930 be done using one of the two options below: 931 932 CONFIG_OF_EMBED 933 If this variable is defined, U-Boot will embed a device tree 934 binary in its image. This device tree file should be in the 935 board directory and called <soc>-<board>.dts. The binary file 936 is then picked up in board_init_f() and made available through 937 the global data structure as gd->blob. 938 939 CONFIG_OF_SEPARATE 940 If this variable is defined, U-Boot will build a device tree 941 binary. It will be called u-boot.dtb. Architecture-specific 942 code will locate it at run-time. Generally this works by: 943 944 cat u-boot.bin u-boot.dtb >image.bin 945 946 and in fact, U-Boot does this for you, creating a file called 947 u-boot-dtb.bin which is useful in the common case. You can 948 still use the individual files if you need something more 949 exotic. 950 951- Watchdog: 952 CONFIG_WATCHDOG 953 If this variable is defined, it enables watchdog 954 support for the SoC. There must be support in the SoC 955 specific code for a watchdog. For the 8xx and 8260 956 CPUs, the SIU Watchdog feature is enabled in the SYPCR 957 register. When supported for a specific SoC is 958 available, then no further board specific code should 959 be needed to use it. 960 961 CONFIG_HW_WATCHDOG 962 When using a watchdog circuitry external to the used 963 SoC, then define this variable and provide board 964 specific code for the "hw_watchdog_reset" function. 965 966- U-Boot Version: 967 CONFIG_VERSION_VARIABLE 968 If this variable is defined, an environment variable 969 named "ver" is created by U-Boot showing the U-Boot 970 version as printed by the "version" command. 971 Any change to this variable will be reverted at the 972 next reset. 973 974- Real-Time Clock: 975 976 When CONFIG_CMD_DATE is selected, the type of the RTC 977 has to be selected, too. Define exactly one of the 978 following options: 979 980 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 981 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 982 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 983 CONFIG_RTC_MC146818 - use MC146818 RTC 984 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 985 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 986 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 987 CONFIG_RTC_DS164x - use Dallas DS164x RTC 988 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 989 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 990 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 991 CONFIG_SYS_RV3029_TCR - enable trickle charger on 992 RV3029 RTC. 993 994 Note that if the RTC uses I2C, then the I2C interface 995 must also be configured. See I2C Support, below. 996 997- GPIO Support: 998 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 999 CONFIG_PCA953X_INFO - enable pca953x info command 1000 1001 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 1002 chip-ngpio pairs that tell the PCA953X driver the number of 1003 pins supported by a particular chip. 1004 1005 Note that if the GPIO device uses I2C, then the I2C interface 1006 must also be configured. See I2C Support, below. 1007 1008- Timestamp Support: 1009 1010 When CONFIG_TIMESTAMP is selected, the timestamp 1011 (date and time) of an image is printed by image 1012 commands like bootm or iminfo. This option is 1013 automatically enabled when you select CONFIG_CMD_DATE . 1014 1015- Partition Labels (disklabels) Supported: 1016 Zero or more of the following: 1017 CONFIG_MAC_PARTITION Apple's MacOS partition table. 1018 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the 1019 Intel architecture, USB sticks, etc. 1020 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc. 1021 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the 1022 bootloader. Note 2TB partition limit; see 1023 disk/part_efi.c 1024 CONFIG_MTD_PARTITIONS Memory Technology Device partition table. 1025 1026 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 1027 CONFIG_CMD_SCSI) you must configure support for at 1028 least one non-MTD partition type as well. 1029 1030- IDE Reset method: 1031 CONFIG_IDE_RESET_ROUTINE - this is defined in several 1032 board configurations files but used nowhere! 1033 1034 CONFIG_IDE_RESET - is this is defined, IDE Reset will 1035 be performed by calling the function 1036 ide_set_reset(int reset) 1037 which has to be defined in a board specific file 1038 1039- ATAPI Support: 1040 CONFIG_ATAPI 1041 1042 Set this to enable ATAPI support. 1043 1044- LBA48 Support 1045 CONFIG_LBA48 1046 1047 Set this to enable support for disks larger than 137GB 1048 Also look at CONFIG_SYS_64BIT_LBA. 1049 Whithout these , LBA48 support uses 32bit variables and will 'only' 1050 support disks up to 2.1TB. 1051 1052 CONFIG_SYS_64BIT_LBA: 1053 When enabled, makes the IDE subsystem use 64bit sector addresses. 1054 Default is 32bit. 1055 1056- SCSI Support: 1057 At the moment only there is only support for the 1058 SYM53C8XX SCSI controller; define 1059 CONFIG_SCSI_SYM53C8XX to enable it. 1060 1061 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 1062 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 1063 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 1064 maximum numbers of LUNs, SCSI ID's and target 1065 devices. 1066 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 1067 1068 The environment variable 'scsidevs' is set to the number of 1069 SCSI devices found during the last scan. 1070 1071- NETWORK Support (PCI): 1072 CONFIG_E1000 1073 Support for Intel 8254x/8257x gigabit chips. 1074 1075 CONFIG_E1000_SPI 1076 Utility code for direct access to the SPI bus on Intel 8257x. 1077 This does not do anything useful unless you set at least one 1078 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 1079 1080 CONFIG_E1000_SPI_GENERIC 1081 Allow generic access to the SPI bus on the Intel 8257x, for 1082 example with the "sspi" command. 1083 1084 CONFIG_CMD_E1000 1085 Management command for E1000 devices. When used on devices 1086 with SPI support you can reprogram the EEPROM from U-Boot. 1087 1088 CONFIG_E1000_FALLBACK_MAC 1089 default MAC for empty EEPROM after production. 1090 1091 CONFIG_EEPRO100 1092 Support for Intel 82557/82559/82559ER chips. 1093 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 1094 write routine for first time initialisation. 1095 1096 CONFIG_TULIP 1097 Support for Digital 2114x chips. 1098 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 1099 modem chip initialisation (KS8761/QS6611). 1100 1101 CONFIG_NATSEMI 1102 Support for National dp83815 chips. 1103 1104 CONFIG_NS8382X 1105 Support for National dp8382[01] gigabit chips. 1106 1107- NETWORK Support (other): 1108 1109 CONFIG_DRIVER_AT91EMAC 1110 Support for AT91RM9200 EMAC. 1111 1112 CONFIG_RMII 1113 Define this to use reduced MII inteface 1114 1115 CONFIG_DRIVER_AT91EMAC_QUIET 1116 If this defined, the driver is quiet. 1117 The driver doen't show link status messages. 1118 1119 CONFIG_CALXEDA_XGMAC 1120 Support for the Calxeda XGMAC device 1121 1122 CONFIG_LAN91C96 1123 Support for SMSC's LAN91C96 chips. 1124 1125 CONFIG_LAN91C96_BASE 1126 Define this to hold the physical address 1127 of the LAN91C96's I/O space 1128 1129 CONFIG_LAN91C96_USE_32_BIT 1130 Define this to enable 32 bit addressing 1131 1132 CONFIG_SMC91111 1133 Support for SMSC's LAN91C111 chip 1134 1135 CONFIG_SMC91111_BASE 1136 Define this to hold the physical address 1137 of the device (I/O space) 1138 1139 CONFIG_SMC_USE_32_BIT 1140 Define this if data bus is 32 bits 1141 1142 CONFIG_SMC_USE_IOFUNCS 1143 Define this to use i/o functions instead of macros 1144 (some hardware wont work with macros) 1145 1146 CONFIG_DRIVER_TI_EMAC 1147 Support for davinci emac 1148 1149 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1150 Define this if you have more then 3 PHYs. 1151 1152 CONFIG_FTGMAC100 1153 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1154 1155 CONFIG_FTGMAC100_EGIGA 1156 Define this to use GE link update with gigabit PHY. 1157 Define this if FTGMAC100 is connected to gigabit PHY. 1158 If your system has 10/100 PHY only, it might not occur 1159 wrong behavior. Because PHY usually return timeout or 1160 useless data when polling gigabit status and gigabit 1161 control registers. This behavior won't affect the 1162 correctnessof 10/100 link speed update. 1163 1164 CONFIG_SMC911X 1165 Support for SMSC's LAN911x and LAN921x chips 1166 1167 CONFIG_SMC911X_BASE 1168 Define this to hold the physical address 1169 of the device (I/O space) 1170 1171 CONFIG_SMC911X_32_BIT 1172 Define this if data bus is 32 bits 1173 1174 CONFIG_SMC911X_16_BIT 1175 Define this if data bus is 16 bits. If your processor 1176 automatically converts one 32 bit word to two 16 bit 1177 words you may also try CONFIG_SMC911X_32_BIT. 1178 1179 CONFIG_SH_ETHER 1180 Support for Renesas on-chip Ethernet controller 1181 1182 CONFIG_SH_ETHER_USE_PORT 1183 Define the number of ports to be used 1184 1185 CONFIG_SH_ETHER_PHY_ADDR 1186 Define the ETH PHY's address 1187 1188 CONFIG_SH_ETHER_CACHE_WRITEBACK 1189 If this option is set, the driver enables cache flush. 1190 1191- TPM Support: 1192 CONFIG_GENERIC_LPC_TPM 1193 Support for generic parallel port TPM devices. Only one device 1194 per system is supported at this time. 1195 1196 CONFIG_TPM_TIS_BASE_ADDRESS 1197 Base address where the generic TPM device is mapped 1198 to. Contemporary x86 systems usually map it at 1199 0xfed40000. 1200 1201- USB Support: 1202 At the moment only the UHCI host controller is 1203 supported (PIP405, MIP405, MPC5200); define 1204 CONFIG_USB_UHCI to enable it. 1205 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1206 and define CONFIG_USB_STORAGE to enable the USB 1207 storage devices. 1208 Note: 1209 Supported are USB Keyboards and USB Floppy drives 1210 (TEAC FD-05PUB). 1211 MPC5200 USB requires additional defines: 1212 CONFIG_USB_CLOCK 1213 for 528 MHz Clock: 0x0001bbbb 1214 CONFIG_PSC3_USB 1215 for USB on PSC3 1216 CONFIG_USB_CONFIG 1217 for differential drivers: 0x00001000 1218 for single ended drivers: 0x00005000 1219 for differential drivers on PSC3: 0x00000100 1220 for single ended drivers on PSC3: 0x00004100 1221 CONFIG_SYS_USB_EVENT_POLL 1222 May be defined to allow interrupt polling 1223 instead of using asynchronous interrupts 1224 1225 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the 1226 txfilltuning field in the EHCI controller on reset. 1227 1228- USB Device: 1229 Define the below if you wish to use the USB console. 1230 Once firmware is rebuilt from a serial console issue the 1231 command "setenv stdin usbtty; setenv stdout usbtty" and 1232 attach your USB cable. The Unix command "dmesg" should print 1233 it has found a new device. The environment variable usbtty 1234 can be set to gserial or cdc_acm to enable your device to 1235 appear to a USB host as a Linux gserial device or a 1236 Common Device Class Abstract Control Model serial device. 1237 If you select usbtty = gserial you should be able to enumerate 1238 a Linux host by 1239 # modprobe usbserial vendor=0xVendorID product=0xProductID 1240 else if using cdc_acm, simply setting the environment 1241 variable usbtty to be cdc_acm should suffice. The following 1242 might be defined in YourBoardName.h 1243 1244 CONFIG_USB_DEVICE 1245 Define this to build a UDC device 1246 1247 CONFIG_USB_TTY 1248 Define this to have a tty type of device available to 1249 talk to the UDC device 1250 1251 CONFIG_USBD_HS 1252 Define this to enable the high speed support for usb 1253 device and usbtty. If this feature is enabled, a routine 1254 int is_usbd_high_speed(void) 1255 also needs to be defined by the driver to dynamically poll 1256 whether the enumeration has succeded at high speed or full 1257 speed. 1258 1259 CONFIG_SYS_CONSOLE_IS_IN_ENV 1260 Define this if you want stdin, stdout &/or stderr to 1261 be set to usbtty. 1262 1263 mpc8xx: 1264 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1265 Derive USB clock from external clock "blah" 1266 - CONFIG_SYS_USB_EXTC_CLK 0x02 1267 1268 CONFIG_SYS_USB_BRG_CLK 0xBLAH 1269 Derive USB clock from brgclk 1270 - CONFIG_SYS_USB_BRG_CLK 0x04 1271 1272 If you have a USB-IF assigned VendorID then you may wish to 1273 define your own vendor specific values either in BoardName.h 1274 or directly in usbd_vendor_info.h. If you don't define 1275 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1276 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1277 should pretend to be a Linux device to it's target host. 1278 1279 CONFIG_USBD_MANUFACTURER 1280 Define this string as the name of your company for 1281 - CONFIG_USBD_MANUFACTURER "my company" 1282 1283 CONFIG_USBD_PRODUCT_NAME 1284 Define this string as the name of your product 1285 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1286 1287 CONFIG_USBD_VENDORID 1288 Define this as your assigned Vendor ID from the USB 1289 Implementors Forum. This *must* be a genuine Vendor ID 1290 to avoid polluting the USB namespace. 1291 - CONFIG_USBD_VENDORID 0xFFFF 1292 1293 CONFIG_USBD_PRODUCTID 1294 Define this as the unique Product ID 1295 for your device 1296 - CONFIG_USBD_PRODUCTID 0xFFFF 1297 1298- ULPI Layer Support: 1299 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via 1300 the generic ULPI layer. The generic layer accesses the ULPI PHY 1301 via the platform viewport, so you need both the genric layer and 1302 the viewport enabled. Currently only Chipidea/ARC based 1303 viewport is supported. 1304 To enable the ULPI layer support, define CONFIG_USB_ULPI and 1305 CONFIG_USB_ULPI_VIEWPORT in your board configuration file. 1306 If your ULPI phy needs a different reference clock than the 1307 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to 1308 the appropriate value in Hz. 1309 1310- MMC Support: 1311 The MMC controller on the Intel PXA is supported. To 1312 enable this define CONFIG_MMC. The MMC can be 1313 accessed from the boot prompt by mapping the device 1314 to physical memory similar to flash. Command line is 1315 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1316 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1317 1318 CONFIG_SH_MMCIF 1319 Support for Renesas on-chip MMCIF controller 1320 1321 CONFIG_SH_MMCIF_ADDR 1322 Define the base address of MMCIF registers 1323 1324 CONFIG_SH_MMCIF_CLK 1325 Define the clock frequency for MMCIF 1326 1327- Journaling Flash filesystem support: 1328 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 1329 CONFIG_JFFS2_NAND_DEV 1330 Define these for a default partition on a NAND device 1331 1332 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1333 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1334 Define these for a default partition on a NOR device 1335 1336 CONFIG_SYS_JFFS_CUSTOM_PART 1337 Define this to create an own partition. You have to provide a 1338 function struct part_info* jffs2_part_info(int part_num) 1339 1340 If you define only one JFFS2 partition you may also want to 1341 #define CONFIG_SYS_JFFS_SINGLE_PART 1 1342 to disable the command chpart. This is the default when you 1343 have not defined a custom partition 1344 1345- FAT(File Allocation Table) filesystem write function support: 1346 CONFIG_FAT_WRITE 1347 1348 Define this to enable support for saving memory data as a 1349 file in FAT formatted partition. 1350 1351 This will also enable the command "fatwrite" enabling the 1352 user to write files to FAT. 1353 1354CBFS (Coreboot Filesystem) support 1355 CONFIG_CMD_CBFS 1356 1357 Define this to enable support for reading from a Coreboot 1358 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls 1359 and cbfsload. 1360 1361- Keyboard Support: 1362 CONFIG_ISA_KEYBOARD 1363 1364 Define this to enable standard (PC-Style) keyboard 1365 support 1366 1367 CONFIG_I8042_KBD 1368 Standard PC keyboard driver with US (is default) and 1369 GERMAN key layout (switch via environment 'keymap=de') support. 1370 Export function i8042_kbd_init, i8042_tstc and i8042_getc 1371 for cfb_console. Supports cursor blinking. 1372 1373- Video support: 1374 CONFIG_VIDEO 1375 1376 Define this to enable video support (for output to 1377 video). 1378 1379 CONFIG_VIDEO_CT69000 1380 1381 Enable Chips & Technologies 69000 Video chip 1382 1383 CONFIG_VIDEO_SMI_LYNXEM 1384 Enable Silicon Motion SMI 712/710/810 Video chip. The 1385 video output is selected via environment 'videoout' 1386 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 1387 assumed. 1388 1389 For the CT69000 and SMI_LYNXEM drivers, videomode is 1390 selected via environment 'videomode'. Two different ways 1391 are possible: 1392 - "videomode=num" 'num' is a standard LiLo mode numbers. 1393 Following standard modes are supported (* is default): 1394 1395 Colors 640x480 800x600 1024x768 1152x864 1280x1024 1396 -------------+--------------------------------------------- 1397 8 bits | 0x301* 0x303 0x305 0x161 0x307 1398 15 bits | 0x310 0x313 0x316 0x162 0x319 1399 16 bits | 0x311 0x314 0x317 0x163 0x31A 1400 24 bits | 0x312 0x315 0x318 ? 0x31B 1401 -------------+--------------------------------------------- 1402 (i.e. setenv videomode 317; saveenv; reset;) 1403 1404 - "videomode=bootargs" all the video parameters are parsed 1405 from the bootargs. (See drivers/video/videomodes.c) 1406 1407 1408 CONFIG_VIDEO_SED13806 1409 Enable Epson SED13806 driver. This driver supports 8bpp 1410 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 1411 or CONFIG_VIDEO_SED13806_16BPP 1412 1413 CONFIG_FSL_DIU_FB 1414 Enable the Freescale DIU video driver. Reference boards for 1415 SOCs that have a DIU should define this macro to enable DIU 1416 support, and should also define these other macros: 1417 1418 CONFIG_SYS_DIU_ADDR 1419 CONFIG_VIDEO 1420 CONFIG_CMD_BMP 1421 CONFIG_CFB_CONSOLE 1422 CONFIG_VIDEO_SW_CURSOR 1423 CONFIG_VGA_AS_SINGLE_DEVICE 1424 CONFIG_VIDEO_LOGO 1425 CONFIG_VIDEO_BMP_LOGO 1426 1427 The DIU driver will look for the 'video-mode' environment 1428 variable, and if defined, enable the DIU as a console during 1429 boot. See the documentation file README.video for a 1430 description of this variable. 1431 1432 CONFIG_VIDEO_VGA 1433 1434 Enable the VGA video / BIOS for x86. The alternative if you 1435 are using coreboot is to use the coreboot frame buffer 1436 driver. 1437 1438 1439- Keyboard Support: 1440 CONFIG_KEYBOARD 1441 1442 Define this to enable a custom keyboard support. 1443 This simply calls drv_keyboard_init() which must be 1444 defined in your board-specific files. 1445 The only board using this so far is RBC823. 1446 1447- LCD Support: CONFIG_LCD 1448 1449 Define this to enable LCD support (for output to LCD 1450 display); also select one of the supported displays 1451 by defining one of these: 1452 1453 CONFIG_ATMEL_LCD: 1454 1455 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1456 1457 CONFIG_NEC_NL6448AC33: 1458 1459 NEC NL6448AC33-18. Active, color, single scan. 1460 1461 CONFIG_NEC_NL6448BC20 1462 1463 NEC NL6448BC20-08. 6.5", 640x480. 1464 Active, color, single scan. 1465 1466 CONFIG_NEC_NL6448BC33_54 1467 1468 NEC NL6448BC33-54. 10.4", 640x480. 1469 Active, color, single scan. 1470 1471 CONFIG_SHARP_16x9 1472 1473 Sharp 320x240. Active, color, single scan. 1474 It isn't 16x9, and I am not sure what it is. 1475 1476 CONFIG_SHARP_LQ64D341 1477 1478 Sharp LQ64D341 display, 640x480. 1479 Active, color, single scan. 1480 1481 CONFIG_HLD1045 1482 1483 HLD1045 display, 640x480. 1484 Active, color, single scan. 1485 1486 CONFIG_OPTREX_BW 1487 1488 Optrex CBL50840-2 NF-FW 99 22 M5 1489 or 1490 Hitachi LMG6912RPFC-00T 1491 or 1492 Hitachi SP14Q002 1493 1494 320x240. Black & white. 1495 1496 Normally display is black on white background; define 1497 CONFIG_SYS_WHITE_ON_BLACK to get it inverted. 1498 1499 CONFIG_LCD_ALIGNMENT 1500 1501 Normally the LCD is page-aligned (tyically 4KB). If this is 1502 defined then the LCD will be aligned to this value instead. 1503 For ARM it is sometimes useful to use MMU_SECTION_SIZE 1504 here, since it is cheaper to change data cache settings on 1505 a per-section basis. 1506 1507 CONFIG_CONSOLE_SCROLL_LINES 1508 1509 When the console need to be scrolled, this is the number of 1510 lines to scroll by. It defaults to 1. Increasing this makes 1511 the console jump but can help speed up operation when scrolling 1512 is slow. 1513 1514 CONFIG_LCD_BMP_RLE8 1515 1516 Support drawing of RLE8-compressed bitmaps on the LCD. 1517 1518 CONFIG_I2C_EDID 1519 1520 Enables an 'i2c edid' command which can read EDID 1521 information over I2C from an attached LCD display. 1522 1523- Splash Screen Support: CONFIG_SPLASH_SCREEN 1524 1525 If this option is set, the environment is checked for 1526 a variable "splashimage". If found, the usual display 1527 of logo, copyright and system information on the LCD 1528 is suppressed and the BMP image at the address 1529 specified in "splashimage" is loaded instead. The 1530 console is redirected to the "nulldev", too. This 1531 allows for a "silent" boot where a splash screen is 1532 loaded very quickly after power-on. 1533 1534 CONFIG_SPLASH_SCREEN_ALIGN 1535 1536 If this option is set the splash image can be freely positioned 1537 on the screen. Environment variable "splashpos" specifies the 1538 position as "x,y". If a positive number is given it is used as 1539 number of pixel from left/top. If a negative number is given it 1540 is used as number of pixel from right/bottom. You can also 1541 specify 'm' for centering the image. 1542 1543 Example: 1544 setenv splashpos m,m 1545 => image at center of screen 1546 1547 setenv splashpos 30,20 1548 => image at x = 30 and y = 20 1549 1550 setenv splashpos -10,m 1551 => vertically centered image 1552 at x = dspWidth - bmpWidth - 9 1553 1554- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1555 1556 If this option is set, additionally to standard BMP 1557 images, gzipped BMP images can be displayed via the 1558 splashscreen support or the bmp command. 1559 1560- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 1561 1562 If this option is set, 8-bit RLE compressed BMP images 1563 can be displayed via the splashscreen support or the 1564 bmp command. 1565 1566- Do compresssing for memory range: 1567 CONFIG_CMD_ZIP 1568 1569 If this option is set, it would use zlib deflate method 1570 to compress the specified memory at its best effort. 1571 1572- Compression support: 1573 CONFIG_BZIP2 1574 1575 If this option is set, support for bzip2 compressed 1576 images is included. If not, only uncompressed and gzip 1577 compressed images are supported. 1578 1579 NOTE: the bzip2 algorithm requires a lot of RAM, so 1580 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 1581 be at least 4MB. 1582 1583 CONFIG_LZMA 1584 1585 If this option is set, support for lzma compressed 1586 images is included. 1587 1588 Note: The LZMA algorithm adds between 2 and 4KB of code and it 1589 requires an amount of dynamic memory that is given by the 1590 formula: 1591 1592 (1846 + 768 << (lc + lp)) * sizeof(uint16) 1593 1594 Where lc and lp stand for, respectively, Literal context bits 1595 and Literal pos bits. 1596 1597 This value is upper-bounded by 14MB in the worst case. Anyway, 1598 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 1599 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 1600 a very small buffer. 1601 1602 Use the lzmainfo tool to determinate the lc and lp values and 1603 then calculate the amount of needed dynamic memory (ensuring 1604 the appropriate CONFIG_SYS_MALLOC_LEN value). 1605 1606- MII/PHY support: 1607 CONFIG_PHY_ADDR 1608 1609 The address of PHY on MII bus. 1610 1611 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1612 1613 The clock frequency of the MII bus 1614 1615 CONFIG_PHY_GIGE 1616 1617 If this option is set, support for speed/duplex 1618 detection of gigabit PHY is included. 1619 1620 CONFIG_PHY_RESET_DELAY 1621 1622 Some PHY like Intel LXT971A need extra delay after 1623 reset before any MII register access is possible. 1624 For such PHY, set this option to the usec delay 1625 required. (minimum 300usec for LXT971A) 1626 1627 CONFIG_PHY_CMD_DELAY (ppc4xx) 1628 1629 Some PHY like Intel LXT971A need extra delay after 1630 command issued before MII status register can be read 1631 1632- Ethernet address: 1633 CONFIG_ETHADDR 1634 CONFIG_ETH1ADDR 1635 CONFIG_ETH2ADDR 1636 CONFIG_ETH3ADDR 1637 CONFIG_ETH4ADDR 1638 CONFIG_ETH5ADDR 1639 1640 Define a default value for Ethernet address to use 1641 for the respective Ethernet interface, in case this 1642 is not determined automatically. 1643 1644- IP address: 1645 CONFIG_IPADDR 1646 1647 Define a default value for the IP address to use for 1648 the default Ethernet interface, in case this is not 1649 determined through e.g. bootp. 1650 (Environment variable "ipaddr") 1651 1652- Server IP address: 1653 CONFIG_SERVERIP 1654 1655 Defines a default value for the IP address of a TFTP 1656 server to contact when using the "tftboot" command. 1657 (Environment variable "serverip") 1658 1659 CONFIG_KEEP_SERVERADDR 1660 1661 Keeps the server's MAC address, in the env 'serveraddr' 1662 for passing to bootargs (like Linux's netconsole option) 1663 1664- Gateway IP address: 1665 CONFIG_GATEWAYIP 1666 1667 Defines a default value for the IP address of the 1668 default router where packets to other networks are 1669 sent to. 1670 (Environment variable "gatewayip") 1671 1672- Subnet mask: 1673 CONFIG_NETMASK 1674 1675 Defines a default value for the subnet mask (or 1676 routing prefix) which is used to determine if an IP 1677 address belongs to the local subnet or needs to be 1678 forwarded through a router. 1679 (Environment variable "netmask") 1680 1681- Multicast TFTP Mode: 1682 CONFIG_MCAST_TFTP 1683 1684 Defines whether you want to support multicast TFTP as per 1685 rfc-2090; for example to work with atftp. Lets lots of targets 1686 tftp down the same boot image concurrently. Note: the Ethernet 1687 driver in use must provide a function: mcast() to join/leave a 1688 multicast group. 1689 1690- BOOTP Recovery Mode: 1691 CONFIG_BOOTP_RANDOM_DELAY 1692 1693 If you have many targets in a network that try to 1694 boot using BOOTP, you may want to avoid that all 1695 systems send out BOOTP requests at precisely the same 1696 moment (which would happen for instance at recovery 1697 from a power failure, when all systems will try to 1698 boot, thus flooding the BOOTP server. Defining 1699 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1700 inserted before sending out BOOTP requests. The 1701 following delays are inserted then: 1702 1703 1st BOOTP request: delay 0 ... 1 sec 1704 2nd BOOTP request: delay 0 ... 2 sec 1705 3rd BOOTP request: delay 0 ... 4 sec 1706 4th and following 1707 BOOTP requests: delay 0 ... 8 sec 1708 1709- DHCP Advanced Options: 1710 You can fine tune the DHCP functionality by defining 1711 CONFIG_BOOTP_* symbols: 1712 1713 CONFIG_BOOTP_SUBNETMASK 1714 CONFIG_BOOTP_GATEWAY 1715 CONFIG_BOOTP_HOSTNAME 1716 CONFIG_BOOTP_NISDOMAIN 1717 CONFIG_BOOTP_BOOTPATH 1718 CONFIG_BOOTP_BOOTFILESIZE 1719 CONFIG_BOOTP_DNS 1720 CONFIG_BOOTP_DNS2 1721 CONFIG_BOOTP_SEND_HOSTNAME 1722 CONFIG_BOOTP_NTPSERVER 1723 CONFIG_BOOTP_TIMEOFFSET 1724 CONFIG_BOOTP_VENDOREX 1725 CONFIG_BOOTP_MAY_FAIL 1726 1727 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 1728 environment variable, not the BOOTP server. 1729 1730 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found 1731 after the configured retry count, the call will fail 1732 instead of starting over. This can be used to fail over 1733 to Link-local IP address configuration if the DHCP server 1734 is not available. 1735 1736 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 1737 serverip from a DHCP server, it is possible that more 1738 than one DNS serverip is offered to the client. 1739 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 1740 serverip will be stored in the additional environment 1741 variable "dnsip2". The first DNS serverip is always 1742 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 1743 is defined. 1744 1745 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 1746 to do a dynamic update of a DNS server. To do this, they 1747 need the hostname of the DHCP requester. 1748 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 1749 of the "hostname" environment variable is passed as 1750 option 12 to the DHCP server. 1751 1752 CONFIG_BOOTP_DHCP_REQUEST_DELAY 1753 1754 A 32bit value in microseconds for a delay between 1755 receiving a "DHCP Offer" and sending the "DHCP Request". 1756 This fixes a problem with certain DHCP servers that don't 1757 respond 100% of the time to a "DHCP request". E.g. On an 1758 AT91RM9200 processor running at 180MHz, this delay needed 1759 to be *at least* 15,000 usec before a Windows Server 2003 1760 DHCP server would reply 100% of the time. I recommend at 1761 least 50,000 usec to be safe. The alternative is to hope 1762 that one of the retries will be successful but note that 1763 the DHCP timeout and retry process takes a longer than 1764 this delay. 1765 1766 - Link-local IP address negotiation: 1767 Negotiate with other link-local clients on the local network 1768 for an address that doesn't require explicit configuration. 1769 This is especially useful if a DHCP server cannot be guaranteed 1770 to exist in all environments that the device must operate. 1771 1772 See doc/README.link-local for more information. 1773 1774 - CDP Options: 1775 CONFIG_CDP_DEVICE_ID 1776 1777 The device id used in CDP trigger frames. 1778 1779 CONFIG_CDP_DEVICE_ID_PREFIX 1780 1781 A two character string which is prefixed to the MAC address 1782 of the device. 1783 1784 CONFIG_CDP_PORT_ID 1785 1786 A printf format string which contains the ascii name of 1787 the port. Normally is set to "eth%d" which sets 1788 eth0 for the first Ethernet, eth1 for the second etc. 1789 1790 CONFIG_CDP_CAPABILITIES 1791 1792 A 32bit integer which indicates the device capabilities; 1793 0x00000010 for a normal host which does not forwards. 1794 1795 CONFIG_CDP_VERSION 1796 1797 An ascii string containing the version of the software. 1798 1799 CONFIG_CDP_PLATFORM 1800 1801 An ascii string containing the name of the platform. 1802 1803 CONFIG_CDP_TRIGGER 1804 1805 A 32bit integer sent on the trigger. 1806 1807 CONFIG_CDP_POWER_CONSUMPTION 1808 1809 A 16bit integer containing the power consumption of the 1810 device in .1 of milliwatts. 1811 1812 CONFIG_CDP_APPLIANCE_VLAN_TYPE 1813 1814 A byte containing the id of the VLAN. 1815 1816- Status LED: CONFIG_STATUS_LED 1817 1818 Several configurations allow to display the current 1819 status using a LED. For instance, the LED will blink 1820 fast while running U-Boot code, stop blinking as 1821 soon as a reply to a BOOTP request was received, and 1822 start blinking slow once the Linux kernel is running 1823 (supported by a status LED driver in the Linux 1824 kernel). Defining CONFIG_STATUS_LED enables this 1825 feature in U-Boot. 1826 1827- CAN Support: CONFIG_CAN_DRIVER 1828 1829 Defining CONFIG_CAN_DRIVER enables CAN driver support 1830 on those systems that support this (optional) 1831 feature, like the TQM8xxL modules. 1832 1833- I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C 1834 1835 These enable I2C serial bus commands. Defining either of 1836 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will 1837 include the appropriate I2C driver for the selected CPU. 1838 1839 This will allow you to use i2c commands at the u-boot 1840 command line (as long as you set CONFIG_CMD_I2C in 1841 CONFIG_COMMANDS) and communicate with i2c based realtime 1842 clock chips. See common/cmd_i2c.c for a description of the 1843 command line interface. 1844 1845 CONFIG_HARD_I2C selects a hardware I2C controller. 1846 1847 CONFIG_SOFT_I2C configures u-boot to use a software (aka 1848 bit-banging) driver instead of CPM or similar hardware 1849 support for I2C. 1850 1851 There are several other quantities that must also be 1852 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C. 1853 1854 In both cases you will need to define CONFIG_SYS_I2C_SPEED 1855 to be the frequency (in Hz) at which you wish your i2c bus 1856 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie 1857 the CPU's i2c node address). 1858 1859 Now, the u-boot i2c code for the mpc8xx 1860 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node 1861 and so its address should therefore be cleared to 0 (See, 1862 eg, MPC823e User's Manual p.16-473). So, set 1863 CONFIG_SYS_I2C_SLAVE to 0. 1864 1865 CONFIG_SYS_I2C_INIT_MPC5XXX 1866 1867 When a board is reset during an i2c bus transfer 1868 chips might think that the current transfer is still 1869 in progress. Reset the slave devices by sending start 1870 commands until the slave device responds. 1871 1872 That's all that's required for CONFIG_HARD_I2C. 1873 1874 If you use the software i2c interface (CONFIG_SOFT_I2C) 1875 then the following macros need to be defined (examples are 1876 from include/configs/lwmon.h): 1877 1878 I2C_INIT 1879 1880 (Optional). Any commands necessary to enable the I2C 1881 controller or configure ports. 1882 1883 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 1884 1885 I2C_PORT 1886 1887 (Only for MPC8260 CPU). The I/O port to use (the code 1888 assumes both bits are on the same port). Valid values 1889 are 0..3 for ports A..D. 1890 1891 I2C_ACTIVE 1892 1893 The code necessary to make the I2C data line active 1894 (driven). If the data line is open collector, this 1895 define can be null. 1896 1897 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 1898 1899 I2C_TRISTATE 1900 1901 The code necessary to make the I2C data line tri-stated 1902 (inactive). If the data line is open collector, this 1903 define can be null. 1904 1905 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 1906 1907 I2C_READ 1908 1909 Code that returns TRUE if the I2C data line is high, 1910 FALSE if it is low. 1911 1912 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 1913 1914 I2C_SDA(bit) 1915 1916 If <bit> is TRUE, sets the I2C data line high. If it 1917 is FALSE, it clears it (low). 1918 1919 eg: #define I2C_SDA(bit) \ 1920 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 1921 else immr->im_cpm.cp_pbdat &= ~PB_SDA 1922 1923 I2C_SCL(bit) 1924 1925 If <bit> is TRUE, sets the I2C clock line high. If it 1926 is FALSE, it clears it (low). 1927 1928 eg: #define I2C_SCL(bit) \ 1929 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 1930 else immr->im_cpm.cp_pbdat &= ~PB_SCL 1931 1932 I2C_DELAY 1933 1934 This delay is invoked four times per clock cycle so this 1935 controls the rate of data transfer. The data rate thus 1936 is 1 / (I2C_DELAY * 4). Often defined to be something 1937 like: 1938 1939 #define I2C_DELAY udelay(2) 1940 1941 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 1942 1943 If your arch supports the generic GPIO framework (asm/gpio.h), 1944 then you may alternatively define the two GPIOs that are to be 1945 used as SCL / SDA. Any of the previous I2C_xxx macros will 1946 have GPIO-based defaults assigned to them as appropriate. 1947 1948 You should define these to the GPIO value as given directly to 1949 the generic GPIO functions. 1950 1951 CONFIG_SYS_I2C_INIT_BOARD 1952 1953 When a board is reset during an i2c bus transfer 1954 chips might think that the current transfer is still 1955 in progress. On some boards it is possible to access 1956 the i2c SCLK line directly, either by using the 1957 processor pin as a GPIO or by having a second pin 1958 connected to the bus. If this option is defined a 1959 custom i2c_init_board() routine in boards/xxx/board.c 1960 is run early in the boot sequence. 1961 1962 CONFIG_SYS_I2C_BOARD_LATE_INIT 1963 1964 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is 1965 defined a custom i2c_board_late_init() routine in 1966 boards/xxx/board.c is run AFTER the operations in i2c_init() 1967 is completed. This callpoint can be used to unreset i2c bus 1968 using CPU i2c controller register accesses for CPUs whose i2c 1969 controller provide such a method. It is called at the end of 1970 i2c_init() to allow i2c_init operations to setup the i2c bus 1971 controller on the CPU (e.g. setting bus speed & slave address). 1972 1973 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 1974 1975 This option enables configuration of bi_iic_fast[] flags 1976 in u-boot bd_info structure based on u-boot environment 1977 variable "i2cfast". (see also i2cfast) 1978 1979 CONFIG_I2C_MULTI_BUS 1980 1981 This option allows the use of multiple I2C buses, each of which 1982 must have a controller. At any point in time, only one bus is 1983 active. To switch to a different bus, use the 'i2c dev' command. 1984 Note that bus numbering is zero-based. 1985 1986 CONFIG_SYS_I2C_NOPROBES 1987 1988 This option specifies a list of I2C devices that will be skipped 1989 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 1990 is set, specify a list of bus-device pairs. Otherwise, specify 1991 a 1D array of device addresses 1992 1993 e.g. 1994 #undef CONFIG_I2C_MULTI_BUS 1995 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 1996 1997 will skip addresses 0x50 and 0x68 on a board with one I2C bus 1998 1999 #define CONFIG_I2C_MULTI_BUS 2000 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 2001 2002 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 2003 2004 CONFIG_SYS_SPD_BUS_NUM 2005 2006 If defined, then this indicates the I2C bus number for DDR SPD. 2007 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 2008 2009 CONFIG_SYS_RTC_BUS_NUM 2010 2011 If defined, then this indicates the I2C bus number for the RTC. 2012 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 2013 2014 CONFIG_SYS_DTT_BUS_NUM 2015 2016 If defined, then this indicates the I2C bus number for the DTT. 2017 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 2018 2019 CONFIG_SYS_I2C_DTT_ADDR: 2020 2021 If defined, specifies the I2C address of the DTT device. 2022 If not defined, then U-Boot uses predefined value for 2023 specified DTT device. 2024 2025 CONFIG_FSL_I2C 2026 2027 Define this option if you want to use Freescale's I2C driver in 2028 drivers/i2c/fsl_i2c.c. 2029 2030 CONFIG_I2C_MUX 2031 2032 Define this option if you have I2C devices reached over 1 .. n 2033 I2C Muxes like the pca9544a. This option addes a new I2C 2034 Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a 2035 new I2C Bus to the existing I2C Busses. If you select the 2036 new Bus with "i2c dev", u-bbot sends first the commandos for 2037 the muxes to activate this new "bus". 2038 2039 CONFIG_I2C_MULTI_BUS must be also defined, to use this 2040 feature! 2041 2042 Example: 2043 Adding a new I2C Bus reached over 2 pca9544a muxes 2044 The First mux with address 70 and channel 6 2045 The Second mux with address 71 and channel 4 2046 2047 => i2c bus pca9544a:70:6:pca9544a:71:4 2048 2049 Use the "i2c bus" command without parameter, to get a list 2050 of I2C Busses with muxes: 2051 2052 => i2c bus 2053 Busses reached over muxes: 2054 Bus ID: 2 2055 reached over Mux(es): 2056 pca9544a@70 ch: 4 2057 Bus ID: 3 2058 reached over Mux(es): 2059 pca9544a@70 ch: 6 2060 pca9544a@71 ch: 4 2061 => 2062 2063 If you now switch to the new I2C Bus 3 with "i2c dev 3" 2064 u-boot first sends the command to the mux@70 to enable 2065 channel 6, and then the command to the mux@71 to enable 2066 the channel 4. 2067 2068 After that, you can use the "normal" i2c commands as 2069 usual to communicate with your I2C devices behind 2070 the 2 muxes. 2071 2072 This option is actually implemented for the bitbanging 2073 algorithm in common/soft_i2c.c and for the Hardware I2C 2074 Bus on the MPC8260. But it should be not so difficult 2075 to add this option to other architectures. 2076 2077 CONFIG_SOFT_I2C_READ_REPEATED_START 2078 2079 defining this will force the i2c_read() function in 2080 the soft_i2c driver to perform an I2C repeated start 2081 between writing the address pointer and reading the 2082 data. If this define is omitted the default behaviour 2083 of doing a stop-start sequence will be used. Most I2C 2084 devices can use either method, but some require one or 2085 the other. 2086 2087- SPI Support: CONFIG_SPI 2088 2089 Enables SPI driver (so far only tested with 2090 SPI EEPROM, also an instance works with Crystal A/D and 2091 D/As on the SACSng board) 2092 2093 CONFIG_SH_SPI 2094 2095 Enables the driver for SPI controller on SuperH. Currently 2096 only SH7757 is supported. 2097 2098 CONFIG_SPI_X 2099 2100 Enables extended (16-bit) SPI EEPROM addressing. 2101 (symmetrical to CONFIG_I2C_X) 2102 2103 CONFIG_SOFT_SPI 2104 2105 Enables a software (bit-bang) SPI driver rather than 2106 using hardware support. This is a general purpose 2107 driver that only requires three general I/O port pins 2108 (two outputs, one input) to function. If this is 2109 defined, the board configuration must define several 2110 SPI configuration items (port pins to use, etc). For 2111 an example, see include/configs/sacsng.h. 2112 2113 CONFIG_HARD_SPI 2114 2115 Enables a hardware SPI driver for general-purpose reads 2116 and writes. As with CONFIG_SOFT_SPI, the board configuration 2117 must define a list of chip-select function pointers. 2118 Currently supported on some MPC8xxx processors. For an 2119 example, see include/configs/mpc8349emds.h. 2120 2121 CONFIG_MXC_SPI 2122 2123 Enables the driver for the SPI controllers on i.MX and MXC 2124 SoCs. Currently i.MX31/35/51 are supported. 2125 2126- FPGA Support: CONFIG_FPGA 2127 2128 Enables FPGA subsystem. 2129 2130 CONFIG_FPGA_<vendor> 2131 2132 Enables support for specific chip vendors. 2133 (ALTERA, XILINX) 2134 2135 CONFIG_FPGA_<family> 2136 2137 Enables support for FPGA family. 2138 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 2139 2140 CONFIG_FPGA_COUNT 2141 2142 Specify the number of FPGA devices to support. 2143 2144 CONFIG_SYS_FPGA_PROG_FEEDBACK 2145 2146 Enable printing of hash marks during FPGA configuration. 2147 2148 CONFIG_SYS_FPGA_CHECK_BUSY 2149 2150 Enable checks on FPGA configuration interface busy 2151 status by the configuration function. This option 2152 will require a board or device specific function to 2153 be written. 2154 2155 CONFIG_FPGA_DELAY 2156 2157 If defined, a function that provides delays in the FPGA 2158 configuration driver. 2159 2160 CONFIG_SYS_FPGA_CHECK_CTRLC 2161 Allow Control-C to interrupt FPGA configuration 2162 2163 CONFIG_SYS_FPGA_CHECK_ERROR 2164 2165 Check for configuration errors during FPGA bitfile 2166 loading. For example, abort during Virtex II 2167 configuration if the INIT_B line goes low (which 2168 indicated a CRC error). 2169 2170 CONFIG_SYS_FPGA_WAIT_INIT 2171 2172 Maximum time to wait for the INIT_B line to deassert 2173 after PROB_B has been deasserted during a Virtex II 2174 FPGA configuration sequence. The default time is 500 2175 ms. 2176 2177 CONFIG_SYS_FPGA_WAIT_BUSY 2178 2179 Maximum time to wait for BUSY to deassert during 2180 Virtex II FPGA configuration. The default is 5 ms. 2181 2182 CONFIG_SYS_FPGA_WAIT_CONFIG 2183 2184 Time to wait after FPGA configuration. The default is 2185 200 ms. 2186 2187- Configuration Management: 2188 CONFIG_IDENT_STRING 2189 2190 If defined, this string will be added to the U-Boot 2191 version information (U_BOOT_VERSION) 2192 2193- Vendor Parameter Protection: 2194 2195 U-Boot considers the values of the environment 2196 variables "serial#" (Board Serial Number) and 2197 "ethaddr" (Ethernet Address) to be parameters that 2198 are set once by the board vendor / manufacturer, and 2199 protects these variables from casual modification by 2200 the user. Once set, these variables are read-only, 2201 and write or delete attempts are rejected. You can 2202 change this behaviour: 2203 2204 If CONFIG_ENV_OVERWRITE is #defined in your config 2205 file, the write protection for vendor parameters is 2206 completely disabled. Anybody can change or delete 2207 these parameters. 2208 2209 Alternatively, if you #define _both_ CONFIG_ETHADDR 2210 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2211 Ethernet address is installed in the environment, 2212 which can be changed exactly ONCE by the user. [The 2213 serial# is unaffected by this, i. e. it remains 2214 read-only.] 2215 2216 The same can be accomplished in a more flexible way 2217 for any variable by configuring the type of access 2218 to allow for those variables in the ".flags" variable 2219 or define CONFIG_ENV_FLAGS_LIST_STATIC. 2220 2221- Protected RAM: 2222 CONFIG_PRAM 2223 2224 Define this variable to enable the reservation of 2225 "protected RAM", i. e. RAM which is not overwritten 2226 by U-Boot. Define CONFIG_PRAM to hold the number of 2227 kB you want to reserve for pRAM. You can overwrite 2228 this default value by defining an environment 2229 variable "pram" to the number of kB you want to 2230 reserve. Note that the board info structure will 2231 still show the full amount of RAM. If pRAM is 2232 reserved, a new environment variable "mem" will 2233 automatically be defined to hold the amount of 2234 remaining RAM in a form that can be passed as boot 2235 argument to Linux, for instance like that: 2236 2237 setenv bootargs ... mem=\${mem} 2238 saveenv 2239 2240 This way you can tell Linux not to use this memory, 2241 either, which results in a memory region that will 2242 not be affected by reboots. 2243 2244 *WARNING* If your board configuration uses automatic 2245 detection of the RAM size, you must make sure that 2246 this memory test is non-destructive. So far, the 2247 following board configurations are known to be 2248 "pRAM-clean": 2249 2250 IVMS8, IVML24, SPD8xx, TQM8xxL, 2251 HERMES, IP860, RPXlite, LWMON, 2252 FLAGADM, TQM8260 2253 2254- Access to physical memory region (> 4GB) 2255 Some basic support is provided for operations on memory not 2256 normally accessible to U-Boot - e.g. some architectures 2257 support access to more than 4GB of memory on 32-bit 2258 machines using physical address extension or similar. 2259 Define CONFIG_PHYSMEM to access this basic support, which 2260 currently only supports clearing the memory. 2261 2262- Error Recovery: 2263 CONFIG_PANIC_HANG 2264 2265 Define this variable to stop the system in case of a 2266 fatal error, so that you have to reset it manually. 2267 This is probably NOT a good idea for an embedded 2268 system where you want the system to reboot 2269 automatically as fast as possible, but it may be 2270 useful during development since you can try to debug 2271 the conditions that lead to the situation. 2272 2273 CONFIG_NET_RETRY_COUNT 2274 2275 This variable defines the number of retries for 2276 network operations like ARP, RARP, TFTP, or BOOTP 2277 before giving up the operation. If not defined, a 2278 default value of 5 is used. 2279 2280 CONFIG_ARP_TIMEOUT 2281 2282 Timeout waiting for an ARP reply in milliseconds. 2283 2284 CONFIG_NFS_TIMEOUT 2285 2286 Timeout in milliseconds used in NFS protocol. 2287 If you encounter "ERROR: Cannot umount" in nfs command, 2288 try longer timeout such as 2289 #define CONFIG_NFS_TIMEOUT 10000UL 2290 2291- Command Interpreter: 2292 CONFIG_AUTO_COMPLETE 2293 2294 Enable auto completion of commands using TAB. 2295 2296 Note that this feature has NOT been implemented yet 2297 for the "hush" shell. 2298 2299 2300 CONFIG_SYS_HUSH_PARSER 2301 2302 Define this variable to enable the "hush" shell (from 2303 Busybox) as command line interpreter, thus enabling 2304 powerful command line syntax like 2305 if...then...else...fi conditionals or `&&' and '||' 2306 constructs ("shell scripts"). 2307 2308 If undefined, you get the old, much simpler behaviour 2309 with a somewhat smaller memory footprint. 2310 2311 2312 CONFIG_SYS_PROMPT_HUSH_PS2 2313 2314 This defines the secondary prompt string, which is 2315 printed when the command interpreter needs more input 2316 to complete a command. Usually "> ". 2317 2318 Note: 2319 2320 In the current implementation, the local variables 2321 space and global environment variables space are 2322 separated. Local variables are those you define by 2323 simply typing `name=value'. To access a local 2324 variable later on, you have write `$name' or 2325 `${name}'; to execute the contents of a variable 2326 directly type `$name' at the command prompt. 2327 2328 Global environment variables are those you use 2329 setenv/printenv to work with. To run a command stored 2330 in such a variable, you need to use the run command, 2331 and you must not use the '$' sign to access them. 2332 2333 To store commands and special characters in a 2334 variable, please use double quotation marks 2335 surrounding the whole text of the variable, instead 2336 of the backslashes before semicolons and special 2337 symbols. 2338 2339- Commandline Editing and History: 2340 CONFIG_CMDLINE_EDITING 2341 2342 Enable editing and History functions for interactive 2343 commandline input operations 2344 2345- Default Environment: 2346 CONFIG_EXTRA_ENV_SETTINGS 2347 2348 Define this to contain any number of null terminated 2349 strings (variable = value pairs) that will be part of 2350 the default environment compiled into the boot image. 2351 2352 For example, place something like this in your 2353 board's config file: 2354 2355 #define CONFIG_EXTRA_ENV_SETTINGS \ 2356 "myvar1=value1\0" \ 2357 "myvar2=value2\0" 2358 2359 Warning: This method is based on knowledge about the 2360 internal format how the environment is stored by the 2361 U-Boot code. This is NOT an official, exported 2362 interface! Although it is unlikely that this format 2363 will change soon, there is no guarantee either. 2364 You better know what you are doing here. 2365 2366 Note: overly (ab)use of the default environment is 2367 discouraged. Make sure to check other ways to preset 2368 the environment like the "source" command or the 2369 boot command first. 2370 2371 CONFIG_ENV_VARS_UBOOT_CONFIG 2372 2373 Define this in order to add variables describing the 2374 U-Boot build configuration to the default environment. 2375 These will be named arch, cpu, board, vendor, and soc. 2376 2377 Enabling this option will cause the following to be defined: 2378 2379 - CONFIG_SYS_ARCH 2380 - CONFIG_SYS_CPU 2381 - CONFIG_SYS_BOARD 2382 - CONFIG_SYS_VENDOR 2383 - CONFIG_SYS_SOC 2384 2385 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG 2386 2387 Define this in order to add variables describing certain 2388 run-time determined information about the hardware to the 2389 environment. These will be named board_name, board_rev. 2390 2391 CONFIG_DELAY_ENVIRONMENT 2392 2393 Normally the environment is loaded when the board is 2394 intialised so that it is available to U-Boot. This inhibits 2395 that so that the environment is not available until 2396 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL 2397 this is instead controlled by the value of 2398 /config/load-environment. 2399 2400- DataFlash Support: 2401 CONFIG_HAS_DATAFLASH 2402 2403 Defining this option enables DataFlash features and 2404 allows to read/write in Dataflash via the standard 2405 commands cp, md... 2406 2407- Serial Flash support 2408 CONFIG_CMD_SF 2409 2410 Defining this option enables SPI flash commands 2411 'sf probe/read/write/erase/update'. 2412 2413 Usage requires an initial 'probe' to define the serial 2414 flash parameters, followed by read/write/erase/update 2415 commands. 2416 2417 The following defaults may be provided by the platform 2418 to handle the common case when only a single serial 2419 flash is present on the system. 2420 2421 CONFIG_SF_DEFAULT_BUS Bus identifier 2422 CONFIG_SF_DEFAULT_CS Chip-select 2423 CONFIG_SF_DEFAULT_MODE (see include/spi.h) 2424 CONFIG_SF_DEFAULT_SPEED in Hz 2425 2426 CONFIG_CMD_SF_TEST 2427 2428 Define this option to include a destructive SPI flash 2429 test ('sf test'). 2430 2431- SystemACE Support: 2432 CONFIG_SYSTEMACE 2433 2434 Adding this option adds support for Xilinx SystemACE 2435 chips attached via some sort of local bus. The address 2436 of the chip must also be defined in the 2437 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 2438 2439 #define CONFIG_SYSTEMACE 2440 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 2441 2442 When SystemACE support is added, the "ace" device type 2443 becomes available to the fat commands, i.e. fatls. 2444 2445- TFTP Fixed UDP Port: 2446 CONFIG_TFTP_PORT 2447 2448 If this is defined, the environment variable tftpsrcp 2449 is used to supply the TFTP UDP source port value. 2450 If tftpsrcp isn't defined, the normal pseudo-random port 2451 number generator is used. 2452 2453 Also, the environment variable tftpdstp is used to supply 2454 the TFTP UDP destination port value. If tftpdstp isn't 2455 defined, the normal port 69 is used. 2456 2457 The purpose for tftpsrcp is to allow a TFTP server to 2458 blindly start the TFTP transfer using the pre-configured 2459 target IP address and UDP port. This has the effect of 2460 "punching through" the (Windows XP) firewall, allowing 2461 the remainder of the TFTP transfer to proceed normally. 2462 A better solution is to properly configure the firewall, 2463 but sometimes that is not allowed. 2464 2465- Hashing support: 2466 CONFIG_CMD_HASH 2467 2468 This enables a generic 'hash' command which can produce 2469 hashes / digests from a few algorithms (e.g. SHA1, SHA256). 2470 2471 CONFIG_HASH_VERIFY 2472 2473 Enable the hash verify command (hash -v). This adds to code 2474 size a little. 2475 2476 CONFIG_SHA1 - support SHA1 hashing 2477 CONFIG_SHA256 - support SHA256 hashing 2478 2479 Note: There is also a sha1sum command, which should perhaps 2480 be deprecated in favour of 'hash sha1'. 2481 2482- Show boot progress: 2483 CONFIG_SHOW_BOOT_PROGRESS 2484 2485 Defining this option allows to add some board- 2486 specific code (calling a user-provided function 2487 "show_boot_progress(int)") that enables you to show 2488 the system's boot progress on some display (for 2489 example, some LED's) on your board. At the moment, 2490 the following checkpoints are implemented: 2491 2492- Detailed boot stage timing 2493 CONFIG_BOOTSTAGE 2494 Define this option to get detailed timing of each stage 2495 of the boot process. 2496 2497 CONFIG_BOOTSTAGE_USER_COUNT 2498 This is the number of available user bootstage records. 2499 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...) 2500 a new ID will be allocated from this stash. If you exceed 2501 the limit, recording will stop. 2502 2503 CONFIG_BOOTSTAGE_REPORT 2504 Define this to print a report before boot, similar to this: 2505 2506 Timer summary in microseconds: 2507 Mark Elapsed Stage 2508 0 0 reset 2509 3,575,678 3,575,678 board_init_f start 2510 3,575,695 17 arch_cpu_init A9 2511 3,575,777 82 arch_cpu_init done 2512 3,659,598 83,821 board_init_r start 2513 3,910,375 250,777 main_loop 2514 29,916,167 26,005,792 bootm_start 2515 30,361,327 445,160 start_kernel 2516 2517 CONFIG_CMD_BOOTSTAGE 2518 Add a 'bootstage' command which supports printing a report 2519 and un/stashing of bootstage data. 2520 2521 CONFIG_BOOTSTAGE_FDT 2522 Stash the bootstage information in the FDT. A root 'bootstage' 2523 node is created with each bootstage id as a child. Each child 2524 has a 'name' property and either 'mark' containing the 2525 mark time in microsecond, or 'accum' containing the 2526 accumulated time for that bootstage id in microseconds. 2527 For example: 2528 2529 bootstage { 2530 154 { 2531 name = "board_init_f"; 2532 mark = <3575678>; 2533 }; 2534 170 { 2535 name = "lcd"; 2536 accum = <33482>; 2537 }; 2538 }; 2539 2540 Code in the Linux kernel can find this in /proc/devicetree. 2541 2542Legacy uImage format: 2543 2544 Arg Where When 2545 1 common/cmd_bootm.c before attempting to boot an image 2546 -1 common/cmd_bootm.c Image header has bad magic number 2547 2 common/cmd_bootm.c Image header has correct magic number 2548 -2 common/cmd_bootm.c Image header has bad checksum 2549 3 common/cmd_bootm.c Image header has correct checksum 2550 -3 common/cmd_bootm.c Image data has bad checksum 2551 4 common/cmd_bootm.c Image data has correct checksum 2552 -4 common/cmd_bootm.c Image is for unsupported architecture 2553 5 common/cmd_bootm.c Architecture check OK 2554 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 2555 6 common/cmd_bootm.c Image Type check OK 2556 -6 common/cmd_bootm.c gunzip uncompression error 2557 -7 common/cmd_bootm.c Unimplemented compression type 2558 7 common/cmd_bootm.c Uncompression OK 2559 8 common/cmd_bootm.c No uncompress/copy overwrite error 2560 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 2561 2562 9 common/image.c Start initial ramdisk verification 2563 -10 common/image.c Ramdisk header has bad magic number 2564 -11 common/image.c Ramdisk header has bad checksum 2565 10 common/image.c Ramdisk header is OK 2566 -12 common/image.c Ramdisk data has bad checksum 2567 11 common/image.c Ramdisk data has correct checksum 2568 12 common/image.c Ramdisk verification complete, start loading 2569 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 2570 13 common/image.c Start multifile image verification 2571 14 common/image.c No initial ramdisk, no multifile, continue. 2572 2573 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 2574 2575 -30 arch/powerpc/lib/board.c Fatal error, hang the system 2576 -31 post/post.c POST test failed, detected by post_output_backlog() 2577 -32 post/post.c POST test failed, detected by post_run_single() 2578 2579 34 common/cmd_doc.c before loading a Image from a DOC device 2580 -35 common/cmd_doc.c Bad usage of "doc" command 2581 35 common/cmd_doc.c correct usage of "doc" command 2582 -36 common/cmd_doc.c No boot device 2583 36 common/cmd_doc.c correct boot device 2584 -37 common/cmd_doc.c Unknown Chip ID on boot device 2585 37 common/cmd_doc.c correct chip ID found, device available 2586 -38 common/cmd_doc.c Read Error on boot device 2587 38 common/cmd_doc.c reading Image header from DOC device OK 2588 -39 common/cmd_doc.c Image header has bad magic number 2589 39 common/cmd_doc.c Image header has correct magic number 2590 -40 common/cmd_doc.c Error reading Image from DOC device 2591 40 common/cmd_doc.c Image header has correct magic number 2592 41 common/cmd_ide.c before loading a Image from a IDE device 2593 -42 common/cmd_ide.c Bad usage of "ide" command 2594 42 common/cmd_ide.c correct usage of "ide" command 2595 -43 common/cmd_ide.c No boot device 2596 43 common/cmd_ide.c boot device found 2597 -44 common/cmd_ide.c Device not available 2598 44 common/cmd_ide.c Device available 2599 -45 common/cmd_ide.c wrong partition selected 2600 45 common/cmd_ide.c partition selected 2601 -46 common/cmd_ide.c Unknown partition table 2602 46 common/cmd_ide.c valid partition table found 2603 -47 common/cmd_ide.c Invalid partition type 2604 47 common/cmd_ide.c correct partition type 2605 -48 common/cmd_ide.c Error reading Image Header on boot device 2606 48 common/cmd_ide.c reading Image Header from IDE device OK 2607 -49 common/cmd_ide.c Image header has bad magic number 2608 49 common/cmd_ide.c Image header has correct magic number 2609 -50 common/cmd_ide.c Image header has bad checksum 2610 50 common/cmd_ide.c Image header has correct checksum 2611 -51 common/cmd_ide.c Error reading Image from IDE device 2612 51 common/cmd_ide.c reading Image from IDE device OK 2613 52 common/cmd_nand.c before loading a Image from a NAND device 2614 -53 common/cmd_nand.c Bad usage of "nand" command 2615 53 common/cmd_nand.c correct usage of "nand" command 2616 -54 common/cmd_nand.c No boot device 2617 54 common/cmd_nand.c boot device found 2618 -55 common/cmd_nand.c Unknown Chip ID on boot device 2619 55 common/cmd_nand.c correct chip ID found, device available 2620 -56 common/cmd_nand.c Error reading Image Header on boot device 2621 56 common/cmd_nand.c reading Image Header from NAND device OK 2622 -57 common/cmd_nand.c Image header has bad magic number 2623 57 common/cmd_nand.c Image header has correct magic number 2624 -58 common/cmd_nand.c Error reading Image from NAND device 2625 58 common/cmd_nand.c reading Image from NAND device OK 2626 2627 -60 common/env_common.c Environment has a bad CRC, using default 2628 2629 64 net/eth.c starting with Ethernet configuration. 2630 -64 net/eth.c no Ethernet found. 2631 65 net/eth.c Ethernet found. 2632 2633 -80 common/cmd_net.c usage wrong 2634 80 common/cmd_net.c before calling NetLoop() 2635 -81 common/cmd_net.c some error in NetLoop() occurred 2636 81 common/cmd_net.c NetLoop() back without error 2637 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 2638 82 common/cmd_net.c trying automatic boot 2639 83 common/cmd_net.c running "source" command 2640 -83 common/cmd_net.c some error in automatic boot or "source" command 2641 84 common/cmd_net.c end without errors 2642 2643FIT uImage format: 2644 2645 Arg Where When 2646 100 common/cmd_bootm.c Kernel FIT Image has correct format 2647 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 2648 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 2649 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 2650 102 common/cmd_bootm.c Kernel unit name specified 2651 -103 common/cmd_bootm.c Can't get kernel subimage node offset 2652 103 common/cmd_bootm.c Found configuration node 2653 104 common/cmd_bootm.c Got kernel subimage node offset 2654 -104 common/cmd_bootm.c Kernel subimage hash verification failed 2655 105 common/cmd_bootm.c Kernel subimage hash verification OK 2656 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 2657 106 common/cmd_bootm.c Architecture check OK 2658 -106 common/cmd_bootm.c Kernel subimage has wrong type 2659 107 common/cmd_bootm.c Kernel subimage type OK 2660 -107 common/cmd_bootm.c Can't get kernel subimage data/size 2661 108 common/cmd_bootm.c Got kernel subimage data/size 2662 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 2663 -109 common/cmd_bootm.c Can't get kernel subimage type 2664 -110 common/cmd_bootm.c Can't get kernel subimage comp 2665 -111 common/cmd_bootm.c Can't get kernel subimage os 2666 -112 common/cmd_bootm.c Can't get kernel subimage load address 2667 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 2668 2669 120 common/image.c Start initial ramdisk verification 2670 -120 common/image.c Ramdisk FIT image has incorrect format 2671 121 common/image.c Ramdisk FIT image has correct format 2672 122 common/image.c No ramdisk subimage unit name, using configuration 2673 -122 common/image.c Can't get configuration for ramdisk subimage 2674 123 common/image.c Ramdisk unit name specified 2675 -124 common/image.c Can't get ramdisk subimage node offset 2676 125 common/image.c Got ramdisk subimage node offset 2677 -125 common/image.c Ramdisk subimage hash verification failed 2678 126 common/image.c Ramdisk subimage hash verification OK 2679 -126 common/image.c Ramdisk subimage for unsupported architecture 2680 127 common/image.c Architecture check OK 2681 -127 common/image.c Can't get ramdisk subimage data/size 2682 128 common/image.c Got ramdisk subimage data/size 2683 129 common/image.c Can't get ramdisk load address 2684 -129 common/image.c Got ramdisk load address 2685 2686 -130 common/cmd_doc.c Incorrect FIT image format 2687 131 common/cmd_doc.c FIT image format OK 2688 2689 -140 common/cmd_ide.c Incorrect FIT image format 2690 141 common/cmd_ide.c FIT image format OK 2691 2692 -150 common/cmd_nand.c Incorrect FIT image format 2693 151 common/cmd_nand.c FIT image format OK 2694 2695- FIT image support: 2696 CONFIG_FIT 2697 Enable support for the FIT uImage format. 2698 2699 CONFIG_FIT_BEST_MATCH 2700 When no configuration is explicitly selected, default to the 2701 one whose fdt's compatibility field best matches that of 2702 U-Boot itself. A match is considered "best" if it matches the 2703 most specific compatibility entry of U-Boot's fdt's root node. 2704 The order of entries in the configuration's fdt is ignored. 2705 2706- Standalone program support: 2707 CONFIG_STANDALONE_LOAD_ADDR 2708 2709 This option defines a board specific value for the 2710 address where standalone program gets loaded, thus 2711 overwriting the architecture dependent default 2712 settings. 2713 2714- Frame Buffer Address: 2715 CONFIG_FB_ADDR 2716 2717 Define CONFIG_FB_ADDR if you want to use specific 2718 address for frame buffer. This is typically the case 2719 when using a graphics controller has separate video 2720 memory. U-Boot will then place the frame buffer at 2721 the given address instead of dynamically reserving it 2722 in system RAM by calling lcd_setmem(), which grabs 2723 the memory for the frame buffer depending on the 2724 configured panel size. 2725 2726 Please see board_init_f function. 2727 2728- Automatic software updates via TFTP server 2729 CONFIG_UPDATE_TFTP 2730 CONFIG_UPDATE_TFTP_CNT_MAX 2731 CONFIG_UPDATE_TFTP_MSEC_MAX 2732 2733 These options enable and control the auto-update feature; 2734 for a more detailed description refer to doc/README.update. 2735 2736- MTD Support (mtdparts command, UBI support) 2737 CONFIG_MTD_DEVICE 2738 2739 Adds the MTD device infrastructure from the Linux kernel. 2740 Needed for mtdparts command support. 2741 2742 CONFIG_MTD_PARTITIONS 2743 2744 Adds the MTD partitioning infrastructure from the Linux 2745 kernel. Needed for UBI support. 2746 2747- SPL framework 2748 CONFIG_SPL 2749 Enable building of SPL globally. 2750 2751 CONFIG_SPL_LDSCRIPT 2752 LDSCRIPT for linking the SPL binary. 2753 2754 CONFIG_SPL_MAX_SIZE 2755 Maximum binary size (text, data and rodata) of the SPL binary. 2756 2757 CONFIG_SPL_TEXT_BASE 2758 TEXT_BASE for linking the SPL binary. 2759 2760 CONFIG_SPL_RELOC_TEXT_BASE 2761 Address to relocate to. If unspecified, this is equal to 2762 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done). 2763 2764 CONFIG_SPL_BSS_START_ADDR 2765 Link address for the BSS within the SPL binary. 2766 2767 CONFIG_SPL_BSS_MAX_SIZE 2768 Maximum binary size of the BSS section of the SPL binary. 2769 2770 CONFIG_SPL_STACK 2771 Adress of the start of the stack SPL will use 2772 2773 CONFIG_SPL_RELOC_STACK 2774 Adress of the start of the stack SPL will use after 2775 relocation. If unspecified, this is equal to 2776 CONFIG_SPL_STACK. 2777 2778 CONFIG_SYS_SPL_MALLOC_START 2779 Starting address of the malloc pool used in SPL. 2780 2781 CONFIG_SYS_SPL_MALLOC_SIZE 2782 The size of the malloc pool used in SPL. 2783 2784 CONFIG_SPL_FRAMEWORK 2785 Enable the SPL framework under common/. This framework 2786 supports MMC, NAND and YMODEM loading of U-Boot and NAND 2787 NAND loading of the Linux Kernel. 2788 2789 CONFIG_SPL_DISPLAY_PRINT 2790 For ARM, enable an optional function to print more information 2791 about the running system. 2792 2793 CONFIG_SPL_INIT_MINIMAL 2794 Arch init code should be built for a very small image 2795 2796 CONFIG_SPL_LIBCOMMON_SUPPORT 2797 Support for common/libcommon.o in SPL binary 2798 2799 CONFIG_SPL_LIBDISK_SUPPORT 2800 Support for disk/libdisk.o in SPL binary 2801 2802 CONFIG_SPL_I2C_SUPPORT 2803 Support for drivers/i2c/libi2c.o in SPL binary 2804 2805 CONFIG_SPL_GPIO_SUPPORT 2806 Support for drivers/gpio/libgpio.o in SPL binary 2807 2808 CONFIG_SPL_MMC_SUPPORT 2809 Support for drivers/mmc/libmmc.o in SPL binary 2810 2811 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR, 2812 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS, 2813 CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION 2814 Address, size and partition on the MMC to load U-Boot from 2815 when the MMC is being used in raw mode. 2816 2817 CONFIG_SPL_FAT_SUPPORT 2818 Support for fs/fat/libfat.o in SPL binary 2819 2820 CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME 2821 Filename to read to load U-Boot when reading from FAT 2822 2823 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND 2824 Set this for NAND SPL on PPC mpc83xx targets, so that 2825 start.S waits for the rest of the SPL to load before 2826 continuing (the hardware starts execution after just 2827 loading the first page rather than the full 4K). 2828 2829 CONFIG_SPL_NAND_BASE 2830 Include nand_base.c in the SPL. Requires 2831 CONFIG_SPL_NAND_DRIVERS. 2832 2833 CONFIG_SPL_NAND_DRIVERS 2834 SPL uses normal NAND drivers, not minimal drivers. 2835 2836 CONFIG_SPL_NAND_ECC 2837 Include standard software ECC in the SPL 2838 2839 CONFIG_SPL_NAND_SIMPLE 2840 Support for NAND boot using simple NAND drivers that 2841 expose the cmd_ctrl() interface. 2842 2843 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT, 2844 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE, 2845 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS, 2846 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE, 2847 CONFIG_SYS_NAND_ECCBYTES 2848 Defines the size and behavior of the NAND that SPL uses 2849 to read U-Boot 2850 2851 CONFIG_SYS_NAND_U_BOOT_OFFS 2852 Location in NAND to read U-Boot from 2853 2854 CONFIG_SYS_NAND_U_BOOT_DST 2855 Location in memory to load U-Boot to 2856 2857 CONFIG_SYS_NAND_U_BOOT_SIZE 2858 Size of image to load 2859 2860 CONFIG_SYS_NAND_U_BOOT_START 2861 Entry point in loaded image to jump to 2862 2863 CONFIG_SYS_NAND_HW_ECC_OOBFIRST 2864 Define this if you need to first read the OOB and then the 2865 data. This is used for example on davinci plattforms. 2866 2867 CONFIG_SPL_OMAP3_ID_NAND 2868 Support for an OMAP3-specific set of functions to return the 2869 ID and MFR of the first attached NAND chip, if present. 2870 2871 CONFIG_SPL_SERIAL_SUPPORT 2872 Support for drivers/serial/libserial.o in SPL binary 2873 2874 CONFIG_SPL_SPI_FLASH_SUPPORT 2875 Support for drivers/mtd/spi/libspi_flash.o in SPL binary 2876 2877 CONFIG_SPL_SPI_SUPPORT 2878 Support for drivers/spi/libspi.o in SPL binary 2879 2880 CONFIG_SPL_RAM_DEVICE 2881 Support for running image already present in ram, in SPL binary 2882 2883 CONFIG_SPL_LIBGENERIC_SUPPORT 2884 Support for lib/libgeneric.o in SPL binary 2885 2886 CONFIG_SPL_PAD_TO 2887 Linker address to which the SPL should be padded before 2888 appending the SPL payload. 2889 2890 CONFIG_SPL_TARGET 2891 Final target image containing SPL and payload. Some SPLs 2892 use an arch-specific makefile fragment instead, for 2893 example if more than one image needs to be produced. 2894 2895Modem Support: 2896-------------- 2897 2898[so far only for SMDK2400 boards] 2899 2900- Modem support enable: 2901 CONFIG_MODEM_SUPPORT 2902 2903- RTS/CTS Flow control enable: 2904 CONFIG_HWFLOW 2905 2906- Modem debug support: 2907 CONFIG_MODEM_SUPPORT_DEBUG 2908 2909 Enables debugging stuff (char screen[1024], dbg()) 2910 for modem support. Useful only with BDI2000. 2911 2912- Interrupt support (PPC): 2913 2914 There are common interrupt_init() and timer_interrupt() 2915 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 2916 for CPU specific initialization. interrupt_init_cpu() 2917 should set decrementer_count to appropriate value. If 2918 CPU resets decrementer automatically after interrupt 2919 (ppc4xx) it should set decrementer_count to zero. 2920 timer_interrupt() calls timer_interrupt_cpu() for CPU 2921 specific handling. If board has watchdog / status_led 2922 / other_activity_monitor it works automatically from 2923 general timer_interrupt(). 2924 2925- General: 2926 2927 In the target system modem support is enabled when a 2928 specific key (key combination) is pressed during 2929 power-on. Otherwise U-Boot will boot normally 2930 (autoboot). The key_pressed() function is called from 2931 board_init(). Currently key_pressed() is a dummy 2932 function, returning 1 and thus enabling modem 2933 initialization. 2934 2935 If there are no modem init strings in the 2936 environment, U-Boot proceed to autoboot; the 2937 previous output (banner, info printfs) will be 2938 suppressed, though. 2939 2940 See also: doc/README.Modem 2941 2942Board initialization settings: 2943------------------------------ 2944 2945During Initialization u-boot calls a number of board specific functions 2946to allow the preparation of board specific prerequisites, e.g. pin setup 2947before drivers are initialized. To enable these callbacks the 2948following configuration macros have to be defined. Currently this is 2949architecture specific, so please check arch/your_architecture/lib/board.c 2950typically in board_init_f() and board_init_r(). 2951 2952- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 2953- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 2954- CONFIG_BOARD_LATE_INIT: Call board_late_init() 2955- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 2956 2957Configuration Settings: 2958----------------------- 2959 2960- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 2961 undefine this when you're short of memory. 2962 2963- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 2964 width of the commands listed in the 'help' command output. 2965 2966- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 2967 prompt for user input. 2968 2969- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 2970 2971- CONFIG_SYS_PBSIZE: Buffer size for Console output 2972 2973- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 2974 2975- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 2976 the application (usually a Linux kernel) when it is 2977 booted 2978 2979- CONFIG_SYS_BAUDRATE_TABLE: 2980 List of legal baudrate settings for this board. 2981 2982- CONFIG_SYS_CONSOLE_INFO_QUIET 2983 Suppress display of console information at boot. 2984 2985- CONFIG_SYS_CONSOLE_IS_IN_ENV 2986 If the board specific function 2987 extern int overwrite_console (void); 2988 returns 1, the stdin, stderr and stdout are switched to the 2989 serial port, else the settings in the environment are used. 2990 2991- CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE 2992 Enable the call to overwrite_console(). 2993 2994- CONFIG_SYS_CONSOLE_ENV_OVERWRITE 2995 Enable overwrite of previous console environment settings. 2996 2997- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 2998 Begin and End addresses of the area used by the 2999 simple memory test. 3000 3001- CONFIG_SYS_ALT_MEMTEST: 3002 Enable an alternate, more extensive memory test. 3003 3004- CONFIG_SYS_MEMTEST_SCRATCH: 3005 Scratch address used by the alternate memory test 3006 You only need to set this if address zero isn't writeable 3007 3008- CONFIG_SYS_MEM_TOP_HIDE (PPC only): 3009 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 3010 this specified memory area will get subtracted from the top 3011 (end) of RAM and won't get "touched" at all by U-Boot. By 3012 fixing up gd->ram_size the Linux kernel should gets passed 3013 the now "corrected" memory size and won't touch it either. 3014 This should work for arch/ppc and arch/powerpc. Only Linux 3015 board ports in arch/powerpc with bootwrapper support that 3016 recalculate the memory size from the SDRAM controller setup 3017 will have to get fixed in Linux additionally. 3018 3019 This option can be used as a workaround for the 440EPx/GRx 3020 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 3021 be touched. 3022 3023 WARNING: Please make sure that this value is a multiple of 3024 the Linux page size (normally 4k). If this is not the case, 3025 then the end address of the Linux memory will be located at a 3026 non page size aligned address and this could cause major 3027 problems. 3028 3029- CONFIG_SYS_LOADS_BAUD_CHANGE: 3030 Enable temporary baudrate change while serial download 3031 3032- CONFIG_SYS_SDRAM_BASE: 3033 Physical start address of SDRAM. _Must_ be 0 here. 3034 3035- CONFIG_SYS_MBIO_BASE: 3036 Physical start address of Motherboard I/O (if using a 3037 Cogent motherboard) 3038 3039- CONFIG_SYS_FLASH_BASE: 3040 Physical start address of Flash memory. 3041 3042- CONFIG_SYS_MONITOR_BASE: 3043 Physical start address of boot monitor code (set by 3044 make config files to be same as the text base address 3045 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 3046 CONFIG_SYS_FLASH_BASE when booting from flash. 3047 3048- CONFIG_SYS_MONITOR_LEN: 3049 Size of memory reserved for monitor code, used to 3050 determine _at_compile_time_ (!) if the environment is 3051 embedded within the U-Boot image, or in a separate 3052 flash sector. 3053 3054- CONFIG_SYS_MALLOC_LEN: 3055 Size of DRAM reserved for malloc() use. 3056 3057- CONFIG_SYS_BOOTM_LEN: 3058 Normally compressed uImages are limited to an 3059 uncompressed size of 8 MBytes. If this is not enough, 3060 you can define CONFIG_SYS_BOOTM_LEN in your board config file 3061 to adjust this setting to your needs. 3062 3063- CONFIG_SYS_BOOTMAPSZ: 3064 Maximum size of memory mapped by the startup code of 3065 the Linux kernel; all data that must be processed by 3066 the Linux kernel (bd_info, boot arguments, FDT blob if 3067 used) must be put below this limit, unless "bootm_low" 3068 enviroment variable is defined and non-zero. In such case 3069 all data for the Linux kernel must be between "bootm_low" 3070 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 3071 variable "bootm_mapsize" will override the value of 3072 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 3073 then the value in "bootm_size" will be used instead. 3074 3075- CONFIG_SYS_BOOT_RAMDISK_HIGH: 3076 Enable initrd_high functionality. If defined then the 3077 initrd_high feature is enabled and the bootm ramdisk subcommand 3078 is enabled. 3079 3080- CONFIG_SYS_BOOT_GET_CMDLINE: 3081 Enables allocating and saving kernel cmdline in space between 3082 "bootm_low" and "bootm_low" + BOOTMAPSZ. 3083 3084- CONFIG_SYS_BOOT_GET_KBD: 3085 Enables allocating and saving a kernel copy of the bd_info in 3086 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 3087 3088- CONFIG_SYS_MAX_FLASH_BANKS: 3089 Max number of Flash memory banks 3090 3091- CONFIG_SYS_MAX_FLASH_SECT: 3092 Max number of sectors on a Flash chip 3093 3094- CONFIG_SYS_FLASH_ERASE_TOUT: 3095 Timeout for Flash erase operations (in ms) 3096 3097- CONFIG_SYS_FLASH_WRITE_TOUT: 3098 Timeout for Flash write operations (in ms) 3099 3100- CONFIG_SYS_FLASH_LOCK_TOUT 3101 Timeout for Flash set sector lock bit operation (in ms) 3102 3103- CONFIG_SYS_FLASH_UNLOCK_TOUT 3104 Timeout for Flash clear lock bits operation (in ms) 3105 3106- CONFIG_SYS_FLASH_PROTECTION 3107 If defined, hardware flash sectors protection is used 3108 instead of U-Boot software protection. 3109 3110- CONFIG_SYS_DIRECT_FLASH_TFTP: 3111 3112 Enable TFTP transfers directly to flash memory; 3113 without this option such a download has to be 3114 performed in two steps: (1) download to RAM, and (2) 3115 copy from RAM to flash. 3116 3117 The two-step approach is usually more reliable, since 3118 you can check if the download worked before you erase 3119 the flash, but in some situations (when system RAM is 3120 too limited to allow for a temporary copy of the 3121 downloaded image) this option may be very useful. 3122 3123- CONFIG_SYS_FLASH_CFI: 3124 Define if the flash driver uses extra elements in the 3125 common flash structure for storing flash geometry. 3126 3127- CONFIG_FLASH_CFI_DRIVER 3128 This option also enables the building of the cfi_flash driver 3129 in the drivers directory 3130 3131- CONFIG_FLASH_CFI_MTD 3132 This option enables the building of the cfi_mtd driver 3133 in the drivers directory. The driver exports CFI flash 3134 to the MTD layer. 3135 3136- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 3137 Use buffered writes to flash. 3138 3139- CONFIG_FLASH_SPANSION_S29WS_N 3140 s29ws-n MirrorBit flash has non-standard addresses for buffered 3141 write commands. 3142 3143- CONFIG_SYS_FLASH_QUIET_TEST 3144 If this option is defined, the common CFI flash doesn't 3145 print it's warning upon not recognized FLASH banks. This 3146 is useful, if some of the configured banks are only 3147 optionally available. 3148 3149- CONFIG_FLASH_SHOW_PROGRESS 3150 If defined (must be an integer), print out countdown 3151 digits and dots. Recommended value: 45 (9..1) for 80 3152 column displays, 15 (3..1) for 40 column displays. 3153 3154- CONFIG_SYS_RX_ETH_BUFFER: 3155 Defines the number of Ethernet receive buffers. On some 3156 Ethernet controllers it is recommended to set this value 3157 to 8 or even higher (EEPRO100 or 405 EMAC), since all 3158 buffers can be full shortly after enabling the interface 3159 on high Ethernet traffic. 3160 Defaults to 4 if not defined. 3161 3162- CONFIG_ENV_MAX_ENTRIES 3163 3164 Maximum number of entries in the hash table that is used 3165 internally to store the environment settings. The default 3166 setting is supposed to be generous and should work in most 3167 cases. This setting can be used to tune behaviour; see 3168 lib/hashtable.c for details. 3169 3170- CONFIG_ENV_FLAGS_LIST_DEFAULT 3171- CONFIG_ENV_FLAGS_LIST_STATIC 3172 Enable validation of the values given to enviroment variables when 3173 calling env set. Variables can be restricted to only decimal, 3174 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined, 3175 the variables can also be restricted to IP address or MAC address. 3176 3177 The format of the list is: 3178 type_attribute = [s|d|x|b|i|m] 3179 access_atribute = [a|r|o|c] 3180 attributes = type_attribute[access_atribute] 3181 entry = variable_name[:attributes] 3182 list = entry[,list] 3183 3184 The type attributes are: 3185 s - String (default) 3186 d - Decimal 3187 x - Hexadecimal 3188 b - Boolean ([1yYtT|0nNfF]) 3189 i - IP address 3190 m - MAC address 3191 3192 The access attributes are: 3193 a - Any (default) 3194 r - Read-only 3195 o - Write-once 3196 c - Change-default 3197 3198 - CONFIG_ENV_FLAGS_LIST_DEFAULT 3199 Define this to a list (string) to define the ".flags" 3200 envirnoment variable in the default or embedded environment. 3201 3202 - CONFIG_ENV_FLAGS_LIST_STATIC 3203 Define this to a list (string) to define validation that 3204 should be done if an entry is not found in the ".flags" 3205 environment variable. To override a setting in the static 3206 list, simply add an entry for the same variable name to the 3207 ".flags" variable. 3208 3209- CONFIG_ENV_ACCESS_IGNORE_FORCE 3210 If defined, don't allow the -f switch to env set override variable 3211 access flags. 3212 3213The following definitions that deal with the placement and management 3214of environment data (variable area); in general, we support the 3215following configurations: 3216 3217- CONFIG_BUILD_ENVCRC: 3218 3219 Builds up envcrc with the target environment so that external utils 3220 may easily extract it and embed it in final U-Boot images. 3221 3222- CONFIG_ENV_IS_IN_FLASH: 3223 3224 Define this if the environment is in flash memory. 3225 3226 a) The environment occupies one whole flash sector, which is 3227 "embedded" in the text segment with the U-Boot code. This 3228 happens usually with "bottom boot sector" or "top boot 3229 sector" type flash chips, which have several smaller 3230 sectors at the start or the end. For instance, such a 3231 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 3232 such a case you would place the environment in one of the 3233 4 kB sectors - with U-Boot code before and after it. With 3234 "top boot sector" type flash chips, you would put the 3235 environment in one of the last sectors, leaving a gap 3236 between U-Boot and the environment. 3237 3238 - CONFIG_ENV_OFFSET: 3239 3240 Offset of environment data (variable area) to the 3241 beginning of flash memory; for instance, with bottom boot 3242 type flash chips the second sector can be used: the offset 3243 for this sector is given here. 3244 3245 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 3246 3247 - CONFIG_ENV_ADDR: 3248 3249 This is just another way to specify the start address of 3250 the flash sector containing the environment (instead of 3251 CONFIG_ENV_OFFSET). 3252 3253 - CONFIG_ENV_SECT_SIZE: 3254 3255 Size of the sector containing the environment. 3256 3257 3258 b) Sometimes flash chips have few, equal sized, BIG sectors. 3259 In such a case you don't want to spend a whole sector for 3260 the environment. 3261 3262 - CONFIG_ENV_SIZE: 3263 3264 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 3265 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 3266 of this flash sector for the environment. This saves 3267 memory for the RAM copy of the environment. 3268 3269 It may also save flash memory if you decide to use this 3270 when your environment is "embedded" within U-Boot code, 3271 since then the remainder of the flash sector could be used 3272 for U-Boot code. It should be pointed out that this is 3273 STRONGLY DISCOURAGED from a robustness point of view: 3274 updating the environment in flash makes it always 3275 necessary to erase the WHOLE sector. If something goes 3276 wrong before the contents has been restored from a copy in 3277 RAM, your target system will be dead. 3278 3279 - CONFIG_ENV_ADDR_REDUND 3280 CONFIG_ENV_SIZE_REDUND 3281 3282 These settings describe a second storage area used to hold 3283 a redundant copy of the environment data, so that there is 3284 a valid backup copy in case there is a power failure during 3285 a "saveenv" operation. 3286 3287BE CAREFUL! Any changes to the flash layout, and some changes to the 3288source code will make it necessary to adapt <board>/u-boot.lds* 3289accordingly! 3290 3291 3292- CONFIG_ENV_IS_IN_NVRAM: 3293 3294 Define this if you have some non-volatile memory device 3295 (NVRAM, battery buffered SRAM) which you want to use for the 3296 environment. 3297 3298 - CONFIG_ENV_ADDR: 3299 - CONFIG_ENV_SIZE: 3300 3301 These two #defines are used to determine the memory area you 3302 want to use for environment. It is assumed that this memory 3303 can just be read and written to, without any special 3304 provision. 3305 3306BE CAREFUL! The first access to the environment happens quite early 3307in U-Boot initalization (when we try to get the setting of for the 3308console baudrate). You *MUST* have mapped your NVRAM area then, or 3309U-Boot will hang. 3310 3311Please note that even with NVRAM we still use a copy of the 3312environment in RAM: we could work on NVRAM directly, but we want to 3313keep settings there always unmodified except somebody uses "saveenv" 3314to save the current settings. 3315 3316 3317- CONFIG_ENV_IS_IN_EEPROM: 3318 3319 Use this if you have an EEPROM or similar serial access 3320 device and a driver for it. 3321 3322 - CONFIG_ENV_OFFSET: 3323 - CONFIG_ENV_SIZE: 3324 3325 These two #defines specify the offset and size of the 3326 environment area within the total memory of your EEPROM. 3327 3328 - CONFIG_SYS_I2C_EEPROM_ADDR: 3329 If defined, specified the chip address of the EEPROM device. 3330 The default address is zero. 3331 3332 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 3333 If defined, the number of bits used to address bytes in a 3334 single page in the EEPROM device. A 64 byte page, for example 3335 would require six bits. 3336 3337 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 3338 If defined, the number of milliseconds to delay between 3339 page writes. The default is zero milliseconds. 3340 3341 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 3342 The length in bytes of the EEPROM memory array address. Note 3343 that this is NOT the chip address length! 3344 3345 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 3346 EEPROM chips that implement "address overflow" are ones 3347 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 3348 address and the extra bits end up in the "chip address" bit 3349 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 3350 byte chips. 3351 3352 Note that we consider the length of the address field to 3353 still be one byte because the extra address bits are hidden 3354 in the chip address. 3355 3356 - CONFIG_SYS_EEPROM_SIZE: 3357 The size in bytes of the EEPROM device. 3358 3359 - CONFIG_ENV_EEPROM_IS_ON_I2C 3360 define this, if you have I2C and SPI activated, and your 3361 EEPROM, which holds the environment, is on the I2C bus. 3362 3363 - CONFIG_I2C_ENV_EEPROM_BUS 3364 if you have an Environment on an EEPROM reached over 3365 I2C muxes, you can define here, how to reach this 3366 EEPROM. For example: 3367 3368 #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0" 3369 3370 EEPROM which holds the environment, is reached over 3371 a pca9547 i2c mux with address 0x70, channel 3. 3372 3373- CONFIG_ENV_IS_IN_DATAFLASH: 3374 3375 Define this if you have a DataFlash memory device which you 3376 want to use for the environment. 3377 3378 - CONFIG_ENV_OFFSET: 3379 - CONFIG_ENV_ADDR: 3380 - CONFIG_ENV_SIZE: 3381 3382 These three #defines specify the offset and size of the 3383 environment area within the total memory of your DataFlash placed 3384 at the specified address. 3385 3386- CONFIG_ENV_IS_IN_REMOTE: 3387 3388 Define this if you have a remote memory space which you 3389 want to use for the local device's environment. 3390 3391 - CONFIG_ENV_ADDR: 3392 - CONFIG_ENV_SIZE: 3393 3394 These two #defines specify the address and size of the 3395 environment area within the remote memory space. The 3396 local device can get the environment from remote memory 3397 space by SRIO or PCIE links. 3398 3399BE CAREFUL! For some special cases, the local device can not use 3400"saveenv" command. For example, the local device will get the 3401environment stored in a remote NOR flash by SRIO or PCIE link, 3402but it can not erase, write this NOR flash by SRIO or PCIE interface. 3403 3404- CONFIG_ENV_IS_IN_NAND: 3405 3406 Define this if you have a NAND device which you want to use 3407 for the environment. 3408 3409 - CONFIG_ENV_OFFSET: 3410 - CONFIG_ENV_SIZE: 3411 3412 These two #defines specify the offset and size of the environment 3413 area within the first NAND device. CONFIG_ENV_OFFSET must be 3414 aligned to an erase block boundary. 3415 3416 - CONFIG_ENV_OFFSET_REDUND (optional): 3417 3418 This setting describes a second storage area of CONFIG_ENV_SIZE 3419 size used to hold a redundant copy of the environment data, so 3420 that there is a valid backup copy in case there is a power failure 3421 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 3422 aligned to an erase block boundary. 3423 3424 - CONFIG_ENV_RANGE (optional): 3425 3426 Specifies the length of the region in which the environment 3427 can be written. This should be a multiple of the NAND device's 3428 block size. Specifying a range with more erase blocks than 3429 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 3430 the range to be avoided. 3431 3432 - CONFIG_ENV_OFFSET_OOB (optional): 3433 3434 Enables support for dynamically retrieving the offset of the 3435 environment from block zero's out-of-band data. The 3436 "nand env.oob" command can be used to record this offset. 3437 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 3438 using CONFIG_ENV_OFFSET_OOB. 3439 3440- CONFIG_NAND_ENV_DST 3441 3442 Defines address in RAM to which the nand_spl code should copy the 3443 environment. If redundant environment is used, it will be copied to 3444 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 3445 3446- CONFIG_SYS_SPI_INIT_OFFSET 3447 3448 Defines offset to the initial SPI buffer area in DPRAM. The 3449 area is used at an early stage (ROM part) if the environment 3450 is configured to reside in the SPI EEPROM: We need a 520 byte 3451 scratch DPRAM area. It is used between the two initialization 3452 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 3453 to be a good choice since it makes it far enough from the 3454 start of the data area as well as from the stack pointer. 3455 3456Please note that the environment is read-only until the monitor 3457has been relocated to RAM and a RAM copy of the environment has been 3458created; also, when using EEPROM you will have to use getenv_f() 3459until then to read environment variables. 3460 3461The environment is protected by a CRC32 checksum. Before the monitor 3462is relocated into RAM, as a result of a bad CRC you will be working 3463with the compiled-in default environment - *silently*!!! [This is 3464necessary, because the first environment variable we need is the 3465"baudrate" setting for the console - if we have a bad CRC, we don't 3466have any device yet where we could complain.] 3467 3468Note: once the monitor has been relocated, then it will complain if 3469the default environment is used; a new CRC is computed as soon as you 3470use the "saveenv" command to store a valid environment. 3471 3472- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 3473 Echo the inverted Ethernet link state to the fault LED. 3474 3475 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 3476 also needs to be defined. 3477 3478- CONFIG_SYS_FAULT_MII_ADDR: 3479 MII address of the PHY to check for the Ethernet link state. 3480 3481- CONFIG_NS16550_MIN_FUNCTIONS: 3482 Define this if you desire to only have use of the NS16550_init 3483 and NS16550_putc functions for the serial driver located at 3484 drivers/serial/ns16550.c. This option is useful for saving 3485 space for already greatly restricted images, including but not 3486 limited to NAND_SPL configurations. 3487 3488- CONFIG_DISPLAY_BOARDINFO 3489 Display information about the board that U-Boot is running on 3490 when U-Boot starts up. The board function checkboard() is called 3491 to do this. 3492 3493- CONFIG_DISPLAY_BOARDINFO_LATE 3494 Similar to the previous option, but display this information 3495 later, once stdio is running and output goes to the LCD, if 3496 present. 3497 3498Low Level (hardware related) configuration options: 3499--------------------------------------------------- 3500 3501- CONFIG_SYS_CACHELINE_SIZE: 3502 Cache Line Size of the CPU. 3503 3504- CONFIG_SYS_DEFAULT_IMMR: 3505 Default address of the IMMR after system reset. 3506 3507 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 3508 and RPXsuper) to be able to adjust the position of 3509 the IMMR register after a reset. 3510 3511- CONFIG_SYS_CCSRBAR_DEFAULT: 3512 Default (power-on reset) physical address of CCSR on Freescale 3513 PowerPC SOCs. 3514 3515- CONFIG_SYS_CCSRBAR: 3516 Virtual address of CCSR. On a 32-bit build, this is typically 3517 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 3518 3519 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 3520 for cross-platform code that uses that macro instead. 3521 3522- CONFIG_SYS_CCSRBAR_PHYS: 3523 Physical address of CCSR. CCSR can be relocated to a new 3524 physical address, if desired. In this case, this macro should 3525 be set to that address. Otherwise, it should be set to the 3526 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 3527 is typically relocated on 36-bit builds. It is recommended 3528 that this macro be defined via the _HIGH and _LOW macros: 3529 3530 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 3531 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 3532 3533- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 3534 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 3535 either 0 (32-bit build) or 0xF (36-bit build). This macro is 3536 used in assembly code, so it must not contain typecasts or 3537 integer size suffixes (e.g. "ULL"). 3538 3539- CONFIG_SYS_CCSRBAR_PHYS_LOW: 3540 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 3541 used in assembly code, so it must not contain typecasts or 3542 integer size suffixes (e.g. "ULL"). 3543 3544- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 3545 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 3546 forced to a value that ensures that CCSR is not relocated. 3547 3548- Floppy Disk Support: 3549 CONFIG_SYS_FDC_DRIVE_NUMBER 3550 3551 the default drive number (default value 0) 3552 3553 CONFIG_SYS_ISA_IO_STRIDE 3554 3555 defines the spacing between FDC chipset registers 3556 (default value 1) 3557 3558 CONFIG_SYS_ISA_IO_OFFSET 3559 3560 defines the offset of register from address. It 3561 depends on which part of the data bus is connected to 3562 the FDC chipset. (default value 0) 3563 3564 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 3565 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 3566 default value. 3567 3568 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 3569 fdc_hw_init() is called at the beginning of the FDC 3570 setup. fdc_hw_init() must be provided by the board 3571 source code. It is used to make hardware dependant 3572 initializations. 3573 3574- CONFIG_IDE_AHB: 3575 Most IDE controllers were designed to be connected with PCI 3576 interface. Only few of them were designed for AHB interface. 3577 When software is doing ATA command and data transfer to 3578 IDE devices through IDE-AHB controller, some additional 3579 registers accessing to these kind of IDE-AHB controller 3580 is requierd. 3581 3582- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 3583 DO NOT CHANGE unless you know exactly what you're 3584 doing! (11-4) [MPC8xx/82xx systems only] 3585 3586- CONFIG_SYS_INIT_RAM_ADDR: 3587 3588 Start address of memory area that can be used for 3589 initial data and stack; please note that this must be 3590 writable memory that is working WITHOUT special 3591 initialization, i. e. you CANNOT use normal RAM which 3592 will become available only after programming the 3593 memory controller and running certain initialization 3594 sequences. 3595 3596 U-Boot uses the following memory types: 3597 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 3598 - MPC824X: data cache 3599 - PPC4xx: data cache 3600 3601- CONFIG_SYS_GBL_DATA_OFFSET: 3602 3603 Offset of the initial data structure in the memory 3604 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 3605 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 3606 data is located at the end of the available space 3607 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 3608 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just 3609 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 3610 CONFIG_SYS_GBL_DATA_OFFSET) downward. 3611 3612 Note: 3613 On the MPC824X (or other systems that use the data 3614 cache for initial memory) the address chosen for 3615 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 3616 point to an otherwise UNUSED address space between 3617 the top of RAM and the start of the PCI space. 3618 3619- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 3620 3621- CONFIG_SYS_SYPCR: System Protection Control (11-9) 3622 3623- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 3624 3625- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 3626 3627- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 3628 3629- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 3630 3631- CONFIG_SYS_OR_TIMING_SDRAM: 3632 SDRAM timing 3633 3634- CONFIG_SYS_MAMR_PTA: 3635 periodic timer for refresh 3636 3637- CONFIG_SYS_DER: Debug Event Register (37-47) 3638 3639- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 3640 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 3641 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 3642 CONFIG_SYS_BR1_PRELIM: 3643 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 3644 3645- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 3646 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 3647 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 3648 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 3649 3650- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 3651 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 3652 Machine Mode Register and Memory Periodic Timer 3653 Prescaler definitions (SDRAM timing) 3654 3655- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 3656 enable I2C microcode relocation patch (MPC8xx); 3657 define relocation offset in DPRAM [DSP2] 3658 3659- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 3660 enable SMC microcode relocation patch (MPC8xx); 3661 define relocation offset in DPRAM [SMC1] 3662 3663- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 3664 enable SPI microcode relocation patch (MPC8xx); 3665 define relocation offset in DPRAM [SCC4] 3666 3667- CONFIG_SYS_USE_OSCCLK: 3668 Use OSCM clock mode on MBX8xx board. Be careful, 3669 wrong setting might damage your board. Read 3670 doc/README.MBX before setting this variable! 3671 3672- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 3673 Offset of the bootmode word in DPRAM used by post 3674 (Power On Self Tests). This definition overrides 3675 #define'd default value in commproc.h resp. 3676 cpm_8260.h. 3677 3678- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 3679 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 3680 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 3681 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 3682 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 3683 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 3684 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 3685 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 3686 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 3687 3688- CONFIG_PCI_DISABLE_PCIE: 3689 Disable PCI-Express on systems where it is supported but not 3690 required. 3691 3692- CONFIG_PCI_ENUM_ONLY 3693 Only scan through and get the devices on the busses. 3694 Don't do any setup work, presumably because someone or 3695 something has already done it, and we don't need to do it 3696 a second time. Useful for platforms that are pre-booted 3697 by coreboot or similar. 3698 3699- CONFIG_SYS_SRIO: 3700 Chip has SRIO or not 3701 3702- CONFIG_SRIO1: 3703 Board has SRIO 1 port available 3704 3705- CONFIG_SRIO2: 3706 Board has SRIO 2 port available 3707 3708- CONFIG_SYS_SRIOn_MEM_VIRT: 3709 Virtual Address of SRIO port 'n' memory region 3710 3711- CONFIG_SYS_SRIOn_MEM_PHYS: 3712 Physical Address of SRIO port 'n' memory region 3713 3714- CONFIG_SYS_SRIOn_MEM_SIZE: 3715 Size of SRIO port 'n' memory region 3716 3717- CONFIG_SYS_NDFC_16 3718 Defined to tell the NDFC that the NAND chip is using a 3719 16 bit bus. 3720 3721- CONFIG_SYS_NDFC_EBC0_CFG 3722 Sets the EBC0_CFG register for the NDFC. If not defined 3723 a default value will be used. 3724 3725- CONFIG_SPD_EEPROM 3726 Get DDR timing information from an I2C EEPROM. Common 3727 with pluggable memory modules such as SODIMMs 3728 3729 SPD_EEPROM_ADDRESS 3730 I2C address of the SPD EEPROM 3731 3732- CONFIG_SYS_SPD_BUS_NUM 3733 If SPD EEPROM is on an I2C bus other than the first 3734 one, specify here. Note that the value must resolve 3735 to something your driver can deal with. 3736 3737- CONFIG_SYS_DDR_RAW_TIMING 3738 Get DDR timing information from other than SPD. Common with 3739 soldered DDR chips onboard without SPD. DDR raw timing 3740 parameters are extracted from datasheet and hard-coded into 3741 header files or board specific files. 3742 3743- CONFIG_FSL_DDR_INTERACTIVE 3744 Enable interactive DDR debugging. See doc/README.fsl-ddr. 3745 3746- CONFIG_SYS_83XX_DDR_USES_CS0 3747 Only for 83xx systems. If specified, then DDR should 3748 be configured using CS0 and CS1 instead of CS2 and CS3. 3749 3750- CONFIG_ETHER_ON_FEC[12] 3751 Define to enable FEC[12] on a 8xx series processor. 3752 3753- CONFIG_FEC[12]_PHY 3754 Define to the hardcoded PHY address which corresponds 3755 to the given FEC; i. e. 3756 #define CONFIG_FEC1_PHY 4 3757 means that the PHY with address 4 is connected to FEC1 3758 3759 When set to -1, means to probe for first available. 3760 3761- CONFIG_FEC[12]_PHY_NORXERR 3762 The PHY does not have a RXERR line (RMII only). 3763 (so program the FEC to ignore it). 3764 3765- CONFIG_RMII 3766 Enable RMII mode for all FECs. 3767 Note that this is a global option, we can't 3768 have one FEC in standard MII mode and another in RMII mode. 3769 3770- CONFIG_CRC32_VERIFY 3771 Add a verify option to the crc32 command. 3772 The syntax is: 3773 3774 => crc32 -v <address> <count> <crc32> 3775 3776 Where address/count indicate a memory area 3777 and crc32 is the correct crc32 which the 3778 area should have. 3779 3780- CONFIG_LOOPW 3781 Add the "loopw" memory command. This only takes effect if 3782 the memory commands are activated globally (CONFIG_CMD_MEM). 3783 3784- CONFIG_MX_CYCLIC 3785 Add the "mdc" and "mwc" memory commands. These are cyclic 3786 "md/mw" commands. 3787 Examples: 3788 3789 => mdc.b 10 4 500 3790 This command will print 4 bytes (10,11,12,13) each 500 ms. 3791 3792 => mwc.l 100 12345678 10 3793 This command will write 12345678 to address 100 all 10 ms. 3794 3795 This only takes effect if the memory commands are activated 3796 globally (CONFIG_CMD_MEM). 3797 3798- CONFIG_SKIP_LOWLEVEL_INIT 3799 [ARM, NDS32, MIPS only] If this variable is defined, then certain 3800 low level initializations (like setting up the memory 3801 controller) are omitted and/or U-Boot does not 3802 relocate itself into RAM. 3803 3804 Normally this variable MUST NOT be defined. The only 3805 exception is when U-Boot is loaded (to RAM) by some 3806 other boot loader or by a debugger which performs 3807 these initializations itself. 3808 3809- CONFIG_SPL_BUILD 3810 Modifies the behaviour of start.S when compiling a loader 3811 that is executed before the actual U-Boot. E.g. when 3812 compiling a NAND SPL. 3813 3814- CONFIG_ARCH_MAP_SYSMEM 3815 Generally U-Boot (and in particular the md command) uses 3816 effective address. It is therefore not necessary to regard 3817 U-Boot address as virtual addresses that need to be translated 3818 to physical addresses. However, sandbox requires this, since 3819 it maintains its own little RAM buffer which contains all 3820 addressable memory. This option causes some memory accesses 3821 to be mapped through map_sysmem() / unmap_sysmem(). 3822 3823- CONFIG_USE_ARCH_MEMCPY 3824 CONFIG_USE_ARCH_MEMSET 3825 If these options are used a optimized version of memcpy/memset will 3826 be used if available. These functions may be faster under some 3827 conditions but may increase the binary size. 3828 3829- CONFIG_X86_RESET_VECTOR 3830 If defined, the x86 reset vector code is included. This is not 3831 needed when U-Boot is running from Coreboot. 3832 3833 3834Freescale QE/FMAN Firmware Support: 3835----------------------------------- 3836 3837The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 3838loading of "firmware", which is encoded in the QE firmware binary format. 3839This firmware often needs to be loaded during U-Boot booting, so macros 3840are used to identify the storage device (NOR flash, SPI, etc) and the address 3841within that device. 3842 3843- CONFIG_SYS_QE_FMAN_FW_ADDR 3844 The address in the storage device where the firmware is located. The 3845 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 3846 is also specified. 3847 3848- CONFIG_SYS_QE_FMAN_FW_LENGTH 3849 The maximum possible size of the firmware. The firmware binary format 3850 has a field that specifies the actual size of the firmware, but it 3851 might not be possible to read any part of the firmware unless some 3852 local storage is allocated to hold the entire firmware first. 3853 3854- CONFIG_SYS_QE_FMAN_FW_IN_NOR 3855 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 3856 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 3857 virtual address in NOR flash. 3858 3859- CONFIG_SYS_QE_FMAN_FW_IN_NAND 3860 Specifies that QE/FMAN firmware is located in NAND flash. 3861 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 3862 3863- CONFIG_SYS_QE_FMAN_FW_IN_MMC 3864 Specifies that QE/FMAN firmware is located on the primary SD/MMC 3865 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 3866 3867- CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH 3868 Specifies that QE/FMAN firmware is located on the primary SPI 3869 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 3870 3871- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE 3872 Specifies that QE/FMAN firmware is located in the remote (master) 3873 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which 3874 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound 3875 window->master inbound window->master LAW->the ucode address in 3876 master's memory space. 3877 3878Building the Software: 3879====================== 3880 3881Building U-Boot has been tested in several native build environments 3882and in many different cross environments. Of course we cannot support 3883all possibly existing versions of cross development tools in all 3884(potentially obsolete) versions. In case of tool chain problems we 3885recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 3886which is extensively used to build and test U-Boot. 3887 3888If you are not using a native environment, it is assumed that you 3889have GNU cross compiling tools available in your path. In this case, 3890you must set the environment variable CROSS_COMPILE in your shell. 3891Note that no changes to the Makefile or any other source files are 3892necessary. For example using the ELDK on a 4xx CPU, please enter: 3893 3894 $ CROSS_COMPILE=ppc_4xx- 3895 $ export CROSS_COMPILE 3896 3897Note: If you wish to generate Windows versions of the utilities in 3898 the tools directory you can use the MinGW toolchain 3899 (http://www.mingw.org). Set your HOST tools to the MinGW 3900 toolchain and execute 'make tools'. For example: 3901 3902 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 3903 3904 Binaries such as tools/mkimage.exe will be created which can 3905 be executed on computers running Windows. 3906 3907U-Boot is intended to be simple to build. After installing the 3908sources you must configure U-Boot for one specific board type. This 3909is done by typing: 3910 3911 make NAME_config 3912 3913where "NAME_config" is the name of one of the existing configu- 3914rations; see boards.cfg for supported names. 3915 3916Note: for some board special configuration names may exist; check if 3917 additional information is available from the board vendor; for 3918 instance, the TQM823L systems are available without (standard) 3919 or with LCD support. You can select such additional "features" 3920 when choosing the configuration, i. e. 3921 3922 make TQM823L_config 3923 - will configure for a plain TQM823L, i. e. no LCD support 3924 3925 make TQM823L_LCD_config 3926 - will configure for a TQM823L with U-Boot console on LCD 3927 3928 etc. 3929 3930 3931Finally, type "make all", and you should get some working U-Boot 3932images ready for download to / installation on your system: 3933 3934- "u-boot.bin" is a raw binary image 3935- "u-boot" is an image in ELF binary format 3936- "u-boot.srec" is in Motorola S-Record format 3937 3938By default the build is performed locally and the objects are saved 3939in the source directory. One of the two methods can be used to change 3940this behavior and build U-Boot to some external directory: 3941 39421. Add O= to the make command line invocations: 3943 3944 make O=/tmp/build distclean 3945 make O=/tmp/build NAME_config 3946 make O=/tmp/build all 3947 39482. Set environment variable BUILD_DIR to point to the desired location: 3949 3950 export BUILD_DIR=/tmp/build 3951 make distclean 3952 make NAME_config 3953 make all 3954 3955Note that the command line "O=" setting overrides the BUILD_DIR environment 3956variable. 3957 3958 3959Please be aware that the Makefiles assume you are using GNU make, so 3960for instance on NetBSD you might need to use "gmake" instead of 3961native "make". 3962 3963 3964If the system board that you have is not listed, then you will need 3965to port U-Boot to your hardware platform. To do this, follow these 3966steps: 3967 39681. Add a new configuration option for your board to the toplevel 3969 "boards.cfg" file, using the existing entries as examples. 3970 Follow the instructions there to keep the boards in order. 39712. Create a new directory to hold your board specific code. Add any 3972 files you need. In your board directory, you will need at least 3973 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 39743. Create a new configuration file "include/configs/<board>.h" for 3975 your board 39763. If you're porting U-Boot to a new CPU, then also create a new 3977 directory to hold your CPU specific code. Add any files you need. 39784. Run "make <board>_config" with your new name. 39795. Type "make", and you should get a working "u-boot.srec" file 3980 to be installed on your target system. 39816. Debug and solve any problems that might arise. 3982 [Of course, this last step is much harder than it sounds.] 3983 3984 3985Testing of U-Boot Modifications, Ports to New Hardware, etc.: 3986============================================================== 3987 3988If you have modified U-Boot sources (for instance added a new board 3989or support for new devices, a new CPU, etc.) you are expected to 3990provide feedback to the other developers. The feedback normally takes 3991the form of a "patch", i. e. a context diff against a certain (latest 3992official or latest in the git repository) version of U-Boot sources. 3993 3994But before you submit such a patch, please verify that your modifi- 3995cation did not break existing code. At least make sure that *ALL* of 3996the supported boards compile WITHOUT ANY compiler warnings. To do so, 3997just run the "MAKEALL" script, which will configure and build U-Boot 3998for ALL supported system. Be warned, this will take a while. You can 3999select which (cross) compiler to use by passing a `CROSS_COMPILE' 4000environment variable to the script, i. e. to use the ELDK cross tools 4001you can type 4002 4003 CROSS_COMPILE=ppc_8xx- MAKEALL 4004 4005or to build on a native PowerPC system you can type 4006 4007 CROSS_COMPILE=' ' MAKEALL 4008 4009When using the MAKEALL script, the default behaviour is to build 4010U-Boot in the source directory. This location can be changed by 4011setting the BUILD_DIR environment variable. Also, for each target 4012built, the MAKEALL script saves two log files (<target>.ERR and 4013<target>.MAKEALL) in the <source dir>/LOG directory. This default 4014location can be changed by setting the MAKEALL_LOGDIR environment 4015variable. For example: 4016 4017 export BUILD_DIR=/tmp/build 4018 export MAKEALL_LOGDIR=/tmp/log 4019 CROSS_COMPILE=ppc_8xx- MAKEALL 4020 4021With the above settings build objects are saved in the /tmp/build, 4022log files are saved in the /tmp/log and the source tree remains clean 4023during the whole build process. 4024 4025 4026See also "U-Boot Porting Guide" below. 4027 4028 4029Monitor Commands - Overview: 4030============================ 4031 4032go - start application at address 'addr' 4033run - run commands in an environment variable 4034bootm - boot application image from memory 4035bootp - boot image via network using BootP/TFTP protocol 4036bootz - boot zImage from memory 4037tftpboot- boot image via network using TFTP protocol 4038 and env variables "ipaddr" and "serverip" 4039 (and eventually "gatewayip") 4040tftpput - upload a file via network using TFTP protocol 4041rarpboot- boot image via network using RARP/TFTP protocol 4042diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 4043loads - load S-Record file over serial line 4044loadb - load binary file over serial line (kermit mode) 4045md - memory display 4046mm - memory modify (auto-incrementing) 4047nm - memory modify (constant address) 4048mw - memory write (fill) 4049cp - memory copy 4050cmp - memory compare 4051crc32 - checksum calculation 4052i2c - I2C sub-system 4053sspi - SPI utility commands 4054base - print or set address offset 4055printenv- print environment variables 4056setenv - set environment variables 4057saveenv - save environment variables to persistent storage 4058protect - enable or disable FLASH write protection 4059erase - erase FLASH memory 4060flinfo - print FLASH memory information 4061nand - NAND memory operations (see doc/README.nand) 4062bdinfo - print Board Info structure 4063iminfo - print header information for application image 4064coninfo - print console devices and informations 4065ide - IDE sub-system 4066loop - infinite loop on address range 4067loopw - infinite write loop on address range 4068mtest - simple RAM test 4069icache - enable or disable instruction cache 4070dcache - enable or disable data cache 4071reset - Perform RESET of the CPU 4072echo - echo args to console 4073version - print monitor version 4074help - print online help 4075? - alias for 'help' 4076 4077 4078Monitor Commands - Detailed Description: 4079======================================== 4080 4081TODO. 4082 4083For now: just type "help <command>". 4084 4085 4086Environment Variables: 4087====================== 4088 4089U-Boot supports user configuration using Environment Variables which 4090can be made persistent by saving to Flash memory. 4091 4092Environment Variables are set using "setenv", printed using 4093"printenv", and saved to Flash using "saveenv". Using "setenv" 4094without a value can be used to delete a variable from the 4095environment. As long as you don't save the environment you are 4096working with an in-memory copy. In case the Flash area containing the 4097environment is erased by accident, a default environment is provided. 4098 4099Some configuration options can be set using Environment Variables. 4100 4101List of environment variables (most likely not complete): 4102 4103 baudrate - see CONFIG_BAUDRATE 4104 4105 bootdelay - see CONFIG_BOOTDELAY 4106 4107 bootcmd - see CONFIG_BOOTCOMMAND 4108 4109 bootargs - Boot arguments when booting an RTOS image 4110 4111 bootfile - Name of the image to load with TFTP 4112 4113 bootm_low - Memory range available for image processing in the bootm 4114 command can be restricted. This variable is given as 4115 a hexadecimal number and defines lowest address allowed 4116 for use by the bootm command. See also "bootm_size" 4117 environment variable. Address defined by "bootm_low" is 4118 also the base of the initial memory mapping for the Linux 4119 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 4120 bootm_mapsize. 4121 4122 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 4123 This variable is given as a hexadecimal number and it 4124 defines the size of the memory region starting at base 4125 address bootm_low that is accessible by the Linux kernel 4126 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 4127 as the default value if it is defined, and bootm_size is 4128 used otherwise. 4129 4130 bootm_size - Memory range available for image processing in the bootm 4131 command can be restricted. This variable is given as 4132 a hexadecimal number and defines the size of the region 4133 allowed for use by the bootm command. See also "bootm_low" 4134 environment variable. 4135 4136 updatefile - Location of the software update file on a TFTP server, used 4137 by the automatic software update feature. Please refer to 4138 documentation in doc/README.update for more details. 4139 4140 autoload - if set to "no" (any string beginning with 'n'), 4141 "bootp" will just load perform a lookup of the 4142 configuration from the BOOTP server, but not try to 4143 load any image using TFTP 4144 4145 autostart - if set to "yes", an image loaded using the "bootp", 4146 "rarpboot", "tftpboot" or "diskboot" commands will 4147 be automatically started (by internally calling 4148 "bootm") 4149 4150 If set to "no", a standalone image passed to the 4151 "bootm" command will be copied to the load address 4152 (and eventually uncompressed), but NOT be started. 4153 This can be used to load and uncompress arbitrary 4154 data. 4155 4156 fdt_high - if set this restricts the maximum address that the 4157 flattened device tree will be copied into upon boot. 4158 For example, if you have a system with 1 GB memory 4159 at physical address 0x10000000, while Linux kernel 4160 only recognizes the first 704 MB as low memory, you 4161 may need to set fdt_high as 0x3C000000 to have the 4162 device tree blob be copied to the maximum address 4163 of the 704 MB low memory, so that Linux kernel can 4164 access it during the boot procedure. 4165 4166 If this is set to the special value 0xFFFFFFFF then 4167 the fdt will not be copied at all on boot. For this 4168 to work it must reside in writable memory, have 4169 sufficient padding on the end of it for u-boot to 4170 add the information it needs into it, and the memory 4171 must be accessible by the kernel. 4172 4173 fdtcontroladdr- if set this is the address of the control flattened 4174 device tree used by U-Boot when CONFIG_OF_CONTROL is 4175 defined. 4176 4177 i2cfast - (PPC405GP|PPC405EP only) 4178 if set to 'y' configures Linux I2C driver for fast 4179 mode (400kHZ). This environment variable is used in 4180 initialization code. So, for changes to be effective 4181 it must be saved and board must be reset. 4182 4183 initrd_high - restrict positioning of initrd images: 4184 If this variable is not set, initrd images will be 4185 copied to the highest possible address in RAM; this 4186 is usually what you want since it allows for 4187 maximum initrd size. If for some reason you want to 4188 make sure that the initrd image is loaded below the 4189 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 4190 variable to a value of "no" or "off" or "0". 4191 Alternatively, you can set it to a maximum upper 4192 address to use (U-Boot will still check that it 4193 does not overwrite the U-Boot stack and data). 4194 4195 For instance, when you have a system with 16 MB 4196 RAM, and want to reserve 4 MB from use by Linux, 4197 you can do this by adding "mem=12M" to the value of 4198 the "bootargs" variable. However, now you must make 4199 sure that the initrd image is placed in the first 4200 12 MB as well - this can be done with 4201 4202 setenv initrd_high 00c00000 4203 4204 If you set initrd_high to 0xFFFFFFFF, this is an 4205 indication to U-Boot that all addresses are legal 4206 for the Linux kernel, including addresses in flash 4207 memory. In this case U-Boot will NOT COPY the 4208 ramdisk at all. This may be useful to reduce the 4209 boot time on your system, but requires that this 4210 feature is supported by your Linux kernel. 4211 4212 ipaddr - IP address; needed for tftpboot command 4213 4214 loadaddr - Default load address for commands like "bootp", 4215 "rarpboot", "tftpboot", "loadb" or "diskboot" 4216 4217 loads_echo - see CONFIG_LOADS_ECHO 4218 4219 serverip - TFTP server IP address; needed for tftpboot command 4220 4221 bootretry - see CONFIG_BOOT_RETRY_TIME 4222 4223 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 4224 4225 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 4226 4227 ethprime - controls which interface is used first. 4228 4229 ethact - controls which interface is currently active. 4230 For example you can do the following 4231 4232 => setenv ethact FEC 4233 => ping 192.168.0.1 # traffic sent on FEC 4234 => setenv ethact SCC 4235 => ping 10.0.0.1 # traffic sent on SCC 4236 4237 ethrotate - When set to "no" U-Boot does not go through all 4238 available network interfaces. 4239 It just stays at the currently selected interface. 4240 4241 netretry - When set to "no" each network operation will 4242 either succeed or fail without retrying. 4243 When set to "once" the network operation will 4244 fail when all the available network interfaces 4245 are tried once without success. 4246 Useful on scripts which control the retry operation 4247 themselves. 4248 4249 npe_ucode - set load address for the NPE microcode 4250 4251 tftpsrcport - If this is set, the value is used for TFTP's 4252 UDP source port. 4253 4254 tftpdstport - If this is set, the value is used for TFTP's UDP 4255 destination port instead of the Well Know Port 69. 4256 4257 tftpblocksize - Block size to use for TFTP transfers; if not set, 4258 we use the TFTP server's default block size 4259 4260 tftptimeout - Retransmission timeout for TFTP packets (in milli- 4261 seconds, minimum value is 1000 = 1 second). Defines 4262 when a packet is considered to be lost so it has to 4263 be retransmitted. The default is 5000 = 5 seconds. 4264 Lowering this value may make downloads succeed 4265 faster in networks with high packet loss rates or 4266 with unreliable TFTP servers. 4267 4268 vlan - When set to a value < 4095 the traffic over 4269 Ethernet is encapsulated/received over 802.1q 4270 VLAN tagged frames. 4271 4272The following image location variables contain the location of images 4273used in booting. The "Image" column gives the role of the image and is 4274not an environment variable name. The other columns are environment 4275variable names. "File Name" gives the name of the file on a TFTP 4276server, "RAM Address" gives the location in RAM the image will be 4277loaded to, and "Flash Location" gives the image's address in NOR 4278flash or offset in NAND flash. 4279 4280*Note* - these variables don't have to be defined for all boards, some 4281boards currenlty use other variables for these purposes, and some 4282boards use these variables for other purposes. 4283 4284Image File Name RAM Address Flash Location 4285----- --------- ----------- -------------- 4286u-boot u-boot u-boot_addr_r u-boot_addr 4287Linux kernel bootfile kernel_addr_r kernel_addr 4288device tree blob fdtfile fdt_addr_r fdt_addr 4289ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 4290 4291The following environment variables may be used and automatically 4292updated by the network boot commands ("bootp" and "rarpboot"), 4293depending the information provided by your boot server: 4294 4295 bootfile - see above 4296 dnsip - IP address of your Domain Name Server 4297 dnsip2 - IP address of your secondary Domain Name Server 4298 gatewayip - IP address of the Gateway (Router) to use 4299 hostname - Target hostname 4300 ipaddr - see above 4301 netmask - Subnet Mask 4302 rootpath - Pathname of the root filesystem on the NFS server 4303 serverip - see above 4304 4305 4306There are two special Environment Variables: 4307 4308 serial# - contains hardware identification information such 4309 as type string and/or serial number 4310 ethaddr - Ethernet address 4311 4312These variables can be set only once (usually during manufacturing of 4313the board). U-Boot refuses to delete or overwrite these variables 4314once they have been set once. 4315 4316 4317Further special Environment Variables: 4318 4319 ver - Contains the U-Boot version string as printed 4320 with the "version" command. This variable is 4321 readonly (see CONFIG_VERSION_VARIABLE). 4322 4323 4324Please note that changes to some configuration parameters may take 4325only effect after the next boot (yes, that's just like Windoze :-). 4326 4327 4328Callback functions for environment variables: 4329--------------------------------------------- 4330 4331For some environment variables, the behavior of u-boot needs to change 4332when their values are changed. This functionailty allows functions to 4333be associated with arbitrary variables. On creation, overwrite, or 4334deletion, the callback will provide the opportunity for some side 4335effect to happen or for the change to be rejected. 4336 4337The callbacks are named and associated with a function using the 4338U_BOOT_ENV_CALLBACK macro in your board or driver code. 4339 4340These callbacks are associated with variables in one of two ways. The 4341static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC 4342in the board configuration to a string that defines a list of 4343associations. The list must be in the following format: 4344 4345 entry = variable_name[:callback_name] 4346 list = entry[,list] 4347 4348If the callback name is not specified, then the callback is deleted. 4349Spaces are also allowed anywhere in the list. 4350 4351Callbacks can also be associated by defining the ".callbacks" variable 4352with the same list format above. Any association in ".callbacks" will 4353override any association in the static list. You can define 4354CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the 4355".callbacks" envirnoment variable in the default or embedded environment. 4356 4357 4358Command Line Parsing: 4359===================== 4360 4361There are two different command line parsers available with U-Boot: 4362the old "simple" one, and the much more powerful "hush" shell: 4363 4364Old, simple command line parser: 4365-------------------------------- 4366 4367- supports environment variables (through setenv / saveenv commands) 4368- several commands on one line, separated by ';' 4369- variable substitution using "... ${name} ..." syntax 4370- special characters ('$', ';') can be escaped by prefixing with '\', 4371 for example: 4372 setenv bootcmd bootm \${address} 4373- You can also escape text by enclosing in single apostrophes, for example: 4374 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 4375 4376Hush shell: 4377----------- 4378 4379- similar to Bourne shell, with control structures like 4380 if...then...else...fi, for...do...done; while...do...done, 4381 until...do...done, ... 4382- supports environment ("global") variables (through setenv / saveenv 4383 commands) and local shell variables (through standard shell syntax 4384 "name=value"); only environment variables can be used with "run" 4385 command 4386 4387General rules: 4388-------------- 4389 4390(1) If a command line (or an environment variable executed by a "run" 4391 command) contains several commands separated by semicolon, and 4392 one of these commands fails, then the remaining commands will be 4393 executed anyway. 4394 4395(2) If you execute several variables with one call to run (i. e. 4396 calling run with a list of variables as arguments), any failing 4397 command will cause "run" to terminate, i. e. the remaining 4398 variables are not executed. 4399 4400Note for Redundant Ethernet Interfaces: 4401======================================= 4402 4403Some boards come with redundant Ethernet interfaces; U-Boot supports 4404such configurations and is capable of automatic selection of a 4405"working" interface when needed. MAC assignment works as follows: 4406 4407Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 4408MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 4409"eth1addr" (=>eth1), "eth2addr", ... 4410 4411If the network interface stores some valid MAC address (for instance 4412in SROM), this is used as default address if there is NO correspon- 4413ding setting in the environment; if the corresponding environment 4414variable is set, this overrides the settings in the card; that means: 4415 4416o If the SROM has a valid MAC address, and there is no address in the 4417 environment, the SROM's address is used. 4418 4419o If there is no valid address in the SROM, and a definition in the 4420 environment exists, then the value from the environment variable is 4421 used. 4422 4423o If both the SROM and the environment contain a MAC address, and 4424 both addresses are the same, this MAC address is used. 4425 4426o If both the SROM and the environment contain a MAC address, and the 4427 addresses differ, the value from the environment is used and a 4428 warning is printed. 4429 4430o If neither SROM nor the environment contain a MAC address, an error 4431 is raised. 4432 4433If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 4434will be programmed into hardware as part of the initialization process. This 4435may be skipped by setting the appropriate 'ethmacskip' environment variable. 4436The naming convention is as follows: 4437"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 4438 4439Image Formats: 4440============== 4441 4442U-Boot is capable of booting (and performing other auxiliary operations on) 4443images in two formats: 4444 4445New uImage format (FIT) 4446----------------------- 4447 4448Flexible and powerful format based on Flattened Image Tree -- FIT (similar 4449to Flattened Device Tree). It allows the use of images with multiple 4450components (several kernels, ramdisks, etc.), with contents protected by 4451SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 4452 4453 4454Old uImage format 4455----------------- 4456 4457Old image format is based on binary files which can be basically anything, 4458preceded by a special header; see the definitions in include/image.h for 4459details; basically, the header defines the following image properties: 4460 4461* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 4462 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 4463 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 4464 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 4465 INTEGRITY). 4466* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 4467 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 4468 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 4469* Compression Type (uncompressed, gzip, bzip2) 4470* Load Address 4471* Entry Point 4472* Image Name 4473* Image Timestamp 4474 4475The header is marked by a special Magic Number, and both the header 4476and the data portions of the image are secured against corruption by 4477CRC32 checksums. 4478 4479 4480Linux Support: 4481============== 4482 4483Although U-Boot should support any OS or standalone application 4484easily, the main focus has always been on Linux during the design of 4485U-Boot. 4486 4487U-Boot includes many features that so far have been part of some 4488special "boot loader" code within the Linux kernel. Also, any 4489"initrd" images to be used are no longer part of one big Linux image; 4490instead, kernel and "initrd" are separate images. This implementation 4491serves several purposes: 4492 4493- the same features can be used for other OS or standalone 4494 applications (for instance: using compressed images to reduce the 4495 Flash memory footprint) 4496 4497- it becomes much easier to port new Linux kernel versions because 4498 lots of low-level, hardware dependent stuff are done by U-Boot 4499 4500- the same Linux kernel image can now be used with different "initrd" 4501 images; of course this also means that different kernel images can 4502 be run with the same "initrd". This makes testing easier (you don't 4503 have to build a new "zImage.initrd" Linux image when you just 4504 change a file in your "initrd"). Also, a field-upgrade of the 4505 software is easier now. 4506 4507 4508Linux HOWTO: 4509============ 4510 4511Porting Linux to U-Boot based systems: 4512--------------------------------------- 4513 4514U-Boot cannot save you from doing all the necessary modifications to 4515configure the Linux device drivers for use with your target hardware 4516(no, we don't intend to provide a full virtual machine interface to 4517Linux :-). 4518 4519But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 4520 4521Just make sure your machine specific header file (for instance 4522include/asm-ppc/tqm8xx.h) includes the same definition of the Board 4523Information structure as we define in include/asm-<arch>/u-boot.h, 4524and make sure that your definition of IMAP_ADDR uses the same value 4525as your U-Boot configuration in CONFIG_SYS_IMMR. 4526 4527 4528Configuring the Linux kernel: 4529----------------------------- 4530 4531No specific requirements for U-Boot. Make sure you have some root 4532device (initial ramdisk, NFS) for your target system. 4533 4534 4535Building a Linux Image: 4536----------------------- 4537 4538With U-Boot, "normal" build targets like "zImage" or "bzImage" are 4539not used. If you use recent kernel source, a new build target 4540"uImage" will exist which automatically builds an image usable by 4541U-Boot. Most older kernels also have support for a "pImage" target, 4542which was introduced for our predecessor project PPCBoot and uses a 4543100% compatible format. 4544 4545Example: 4546 4547 make TQM850L_config 4548 make oldconfig 4549 make dep 4550 make uImage 4551 4552The "uImage" build target uses a special tool (in 'tools/mkimage') to 4553encapsulate a compressed Linux kernel image with header information, 4554CRC32 checksum etc. for use with U-Boot. This is what we are doing: 4555 4556* build a standard "vmlinux" kernel image (in ELF binary format): 4557 4558* convert the kernel into a raw binary image: 4559 4560 ${CROSS_COMPILE}-objcopy -O binary \ 4561 -R .note -R .comment \ 4562 -S vmlinux linux.bin 4563 4564* compress the binary image: 4565 4566 gzip -9 linux.bin 4567 4568* package compressed binary image for U-Boot: 4569 4570 mkimage -A ppc -O linux -T kernel -C gzip \ 4571 -a 0 -e 0 -n "Linux Kernel Image" \ 4572 -d linux.bin.gz uImage 4573 4574 4575The "mkimage" tool can also be used to create ramdisk images for use 4576with U-Boot, either separated from the Linux kernel image, or 4577combined into one file. "mkimage" encapsulates the images with a 64 4578byte header containing information about target architecture, 4579operating system, image type, compression method, entry points, time 4580stamp, CRC32 checksums, etc. 4581 4582"mkimage" can be called in two ways: to verify existing images and 4583print the header information, or to build new images. 4584 4585In the first form (with "-l" option) mkimage lists the information 4586contained in the header of an existing U-Boot image; this includes 4587checksum verification: 4588 4589 tools/mkimage -l image 4590 -l ==> list image header information 4591 4592The second form (with "-d" option) is used to build a U-Boot image 4593from a "data file" which is used as image payload: 4594 4595 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 4596 -n name -d data_file image 4597 -A ==> set architecture to 'arch' 4598 -O ==> set operating system to 'os' 4599 -T ==> set image type to 'type' 4600 -C ==> set compression type 'comp' 4601 -a ==> set load address to 'addr' (hex) 4602 -e ==> set entry point to 'ep' (hex) 4603 -n ==> set image name to 'name' 4604 -d ==> use image data from 'datafile' 4605 4606Right now, all Linux kernels for PowerPC systems use the same load 4607address (0x00000000), but the entry point address depends on the 4608kernel version: 4609 4610- 2.2.x kernels have the entry point at 0x0000000C, 4611- 2.3.x and later kernels have the entry point at 0x00000000. 4612 4613So a typical call to build a U-Boot image would read: 4614 4615 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 4616 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 4617 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 4618 > examples/uImage.TQM850L 4619 Image Name: 2.4.4 kernel for TQM850L 4620 Created: Wed Jul 19 02:34:59 2000 4621 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4622 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 4623 Load Address: 0x00000000 4624 Entry Point: 0x00000000 4625 4626To verify the contents of the image (or check for corruption): 4627 4628 -> tools/mkimage -l examples/uImage.TQM850L 4629 Image Name: 2.4.4 kernel for TQM850L 4630 Created: Wed Jul 19 02:34:59 2000 4631 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4632 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 4633 Load Address: 0x00000000 4634 Entry Point: 0x00000000 4635 4636NOTE: for embedded systems where boot time is critical you can trade 4637speed for memory and install an UNCOMPRESSED image instead: this 4638needs more space in Flash, but boots much faster since it does not 4639need to be uncompressed: 4640 4641 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 4642 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 4643 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 4644 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 4645 > examples/uImage.TQM850L-uncompressed 4646 Image Name: 2.4.4 kernel for TQM850L 4647 Created: Wed Jul 19 02:34:59 2000 4648 Image Type: PowerPC Linux Kernel Image (uncompressed) 4649 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 4650 Load Address: 0x00000000 4651 Entry Point: 0x00000000 4652 4653 4654Similar you can build U-Boot images from a 'ramdisk.image.gz' file 4655when your kernel is intended to use an initial ramdisk: 4656 4657 -> tools/mkimage -n 'Simple Ramdisk Image' \ 4658 > -A ppc -O linux -T ramdisk -C gzip \ 4659 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 4660 Image Name: Simple Ramdisk Image 4661 Created: Wed Jan 12 14:01:50 2000 4662 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 4663 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 4664 Load Address: 0x00000000 4665 Entry Point: 0x00000000 4666 4667 4668Installing a Linux Image: 4669------------------------- 4670 4671To downloading a U-Boot image over the serial (console) interface, 4672you must convert the image to S-Record format: 4673 4674 objcopy -I binary -O srec examples/image examples/image.srec 4675 4676The 'objcopy' does not understand the information in the U-Boot 4677image header, so the resulting S-Record file will be relative to 4678address 0x00000000. To load it to a given address, you need to 4679specify the target address as 'offset' parameter with the 'loads' 4680command. 4681 4682Example: install the image to address 0x40100000 (which on the 4683TQM8xxL is in the first Flash bank): 4684 4685 => erase 40100000 401FFFFF 4686 4687 .......... done 4688 Erased 8 sectors 4689 4690 => loads 40100000 4691 ## Ready for S-Record download ... 4692 ~>examples/image.srec 4693 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 4694 ... 4695 15989 15990 15991 15992 4696 [file transfer complete] 4697 [connected] 4698 ## Start Addr = 0x00000000 4699 4700 4701You can check the success of the download using the 'iminfo' command; 4702this includes a checksum verification so you can be sure no data 4703corruption happened: 4704 4705 => imi 40100000 4706 4707 ## Checking Image at 40100000 ... 4708 Image Name: 2.2.13 for initrd on TQM850L 4709 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4710 Data Size: 335725 Bytes = 327 kB = 0 MB 4711 Load Address: 00000000 4712 Entry Point: 0000000c 4713 Verifying Checksum ... OK 4714 4715 4716Boot Linux: 4717----------- 4718 4719The "bootm" command is used to boot an application that is stored in 4720memory (RAM or Flash). In case of a Linux kernel image, the contents 4721of the "bootargs" environment variable is passed to the kernel as 4722parameters. You can check and modify this variable using the 4723"printenv" and "setenv" commands: 4724 4725 4726 => printenv bootargs 4727 bootargs=root=/dev/ram 4728 4729 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 4730 4731 => printenv bootargs 4732 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 4733 4734 => bootm 40020000 4735 ## Booting Linux kernel at 40020000 ... 4736 Image Name: 2.2.13 for NFS on TQM850L 4737 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4738 Data Size: 381681 Bytes = 372 kB = 0 MB 4739 Load Address: 00000000 4740 Entry Point: 0000000c 4741 Verifying Checksum ... OK 4742 Uncompressing Kernel Image ... OK 4743 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 4744 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 4745 time_init: decrementer frequency = 187500000/60 4746 Calibrating delay loop... 49.77 BogoMIPS 4747 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 4748 ... 4749 4750If you want to boot a Linux kernel with initial RAM disk, you pass 4751the memory addresses of both the kernel and the initrd image (PPBCOOT 4752format!) to the "bootm" command: 4753 4754 => imi 40100000 40200000 4755 4756 ## Checking Image at 40100000 ... 4757 Image Name: 2.2.13 for initrd on TQM850L 4758 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4759 Data Size: 335725 Bytes = 327 kB = 0 MB 4760 Load Address: 00000000 4761 Entry Point: 0000000c 4762 Verifying Checksum ... OK 4763 4764 ## Checking Image at 40200000 ... 4765 Image Name: Simple Ramdisk Image 4766 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 4767 Data Size: 566530 Bytes = 553 kB = 0 MB 4768 Load Address: 00000000 4769 Entry Point: 00000000 4770 Verifying Checksum ... OK 4771 4772 => bootm 40100000 40200000 4773 ## Booting Linux kernel at 40100000 ... 4774 Image Name: 2.2.13 for initrd on TQM850L 4775 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4776 Data Size: 335725 Bytes = 327 kB = 0 MB 4777 Load Address: 00000000 4778 Entry Point: 0000000c 4779 Verifying Checksum ... OK 4780 Uncompressing Kernel Image ... OK 4781 ## Loading RAMDisk Image at 40200000 ... 4782 Image Name: Simple Ramdisk Image 4783 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 4784 Data Size: 566530 Bytes = 553 kB = 0 MB 4785 Load Address: 00000000 4786 Entry Point: 00000000 4787 Verifying Checksum ... OK 4788 Loading Ramdisk ... OK 4789 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 4790 Boot arguments: root=/dev/ram 4791 time_init: decrementer frequency = 187500000/60 4792 Calibrating delay loop... 49.77 BogoMIPS 4793 ... 4794 RAMDISK: Compressed image found at block 0 4795 VFS: Mounted root (ext2 filesystem). 4796 4797 bash# 4798 4799Boot Linux and pass a flat device tree: 4800----------- 4801 4802First, U-Boot must be compiled with the appropriate defines. See the section 4803titled "Linux Kernel Interface" above for a more in depth explanation. The 4804following is an example of how to start a kernel and pass an updated 4805flat device tree: 4806 4807=> print oftaddr 4808oftaddr=0x300000 4809=> print oft 4810oft=oftrees/mpc8540ads.dtb 4811=> tftp $oftaddr $oft 4812Speed: 1000, full duplex 4813Using TSEC0 device 4814TFTP from server 192.168.1.1; our IP address is 192.168.1.101 4815Filename 'oftrees/mpc8540ads.dtb'. 4816Load address: 0x300000 4817Loading: # 4818done 4819Bytes transferred = 4106 (100a hex) 4820=> tftp $loadaddr $bootfile 4821Speed: 1000, full duplex 4822Using TSEC0 device 4823TFTP from server 192.168.1.1; our IP address is 192.168.1.2 4824Filename 'uImage'. 4825Load address: 0x200000 4826Loading:############ 4827done 4828Bytes transferred = 1029407 (fb51f hex) 4829=> print loadaddr 4830loadaddr=200000 4831=> print oftaddr 4832oftaddr=0x300000 4833=> bootm $loadaddr - $oftaddr 4834## Booting image at 00200000 ... 4835 Image Name: Linux-2.6.17-dirty 4836 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4837 Data Size: 1029343 Bytes = 1005.2 kB 4838 Load Address: 00000000 4839 Entry Point: 00000000 4840 Verifying Checksum ... OK 4841 Uncompressing Kernel Image ... OK 4842Booting using flat device tree at 0x300000 4843Using MPC85xx ADS machine description 4844Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 4845[snip] 4846 4847 4848More About U-Boot Image Types: 4849------------------------------ 4850 4851U-Boot supports the following image types: 4852 4853 "Standalone Programs" are directly runnable in the environment 4854 provided by U-Boot; it is expected that (if they behave 4855 well) you can continue to work in U-Boot after return from 4856 the Standalone Program. 4857 "OS Kernel Images" are usually images of some Embedded OS which 4858 will take over control completely. Usually these programs 4859 will install their own set of exception handlers, device 4860 drivers, set up the MMU, etc. - this means, that you cannot 4861 expect to re-enter U-Boot except by resetting the CPU. 4862 "RAMDisk Images" are more or less just data blocks, and their 4863 parameters (address, size) are passed to an OS kernel that is 4864 being started. 4865 "Multi-File Images" contain several images, typically an OS 4866 (Linux) kernel image and one or more data images like 4867 RAMDisks. This construct is useful for instance when you want 4868 to boot over the network using BOOTP etc., where the boot 4869 server provides just a single image file, but you want to get 4870 for instance an OS kernel and a RAMDisk image. 4871 4872 "Multi-File Images" start with a list of image sizes, each 4873 image size (in bytes) specified by an "uint32_t" in network 4874 byte order. This list is terminated by an "(uint32_t)0". 4875 Immediately after the terminating 0 follow the images, one by 4876 one, all aligned on "uint32_t" boundaries (size rounded up to 4877 a multiple of 4 bytes). 4878 4879 "Firmware Images" are binary images containing firmware (like 4880 U-Boot or FPGA images) which usually will be programmed to 4881 flash memory. 4882 4883 "Script files" are command sequences that will be executed by 4884 U-Boot's command interpreter; this feature is especially 4885 useful when you configure U-Boot to use a real shell (hush) 4886 as command interpreter. 4887 4888Booting the Linux zImage: 4889------------------------- 4890 4891On some platforms, it's possible to boot Linux zImage. This is done 4892using the "bootz" command. The syntax of "bootz" command is the same 4893as the syntax of "bootm" command. 4894 4895Note, defining the CONFIG_SUPPORT_INITRD_RAW allows user to supply 4896kernel with raw initrd images. The syntax is slightly different, the 4897address of the initrd must be augmented by it's size, in the following 4898format: "<initrd addres>:<initrd size>". 4899 4900 4901Standalone HOWTO: 4902================= 4903 4904One of the features of U-Boot is that you can dynamically load and 4905run "standalone" applications, which can use some resources of 4906U-Boot like console I/O functions or interrupt services. 4907 4908Two simple examples are included with the sources: 4909 4910"Hello World" Demo: 4911------------------- 4912 4913'examples/hello_world.c' contains a small "Hello World" Demo 4914application; it is automatically compiled when you build U-Boot. 4915It's configured to run at address 0x00040004, so you can play with it 4916like that: 4917 4918 => loads 4919 ## Ready for S-Record download ... 4920 ~>examples/hello_world.srec 4921 1 2 3 4 5 6 7 8 9 10 11 ... 4922 [file transfer complete] 4923 [connected] 4924 ## Start Addr = 0x00040004 4925 4926 => go 40004 Hello World! This is a test. 4927 ## Starting application at 0x00040004 ... 4928 Hello World 4929 argc = 7 4930 argv[0] = "40004" 4931 argv[1] = "Hello" 4932 argv[2] = "World!" 4933 argv[3] = "This" 4934 argv[4] = "is" 4935 argv[5] = "a" 4936 argv[6] = "test." 4937 argv[7] = "<NULL>" 4938 Hit any key to exit ... 4939 4940 ## Application terminated, rc = 0x0 4941 4942Another example, which demonstrates how to register a CPM interrupt 4943handler with the U-Boot code, can be found in 'examples/timer.c'. 4944Here, a CPM timer is set up to generate an interrupt every second. 4945The interrupt service routine is trivial, just printing a '.' 4946character, but this is just a demo program. The application can be 4947controlled by the following keys: 4948 4949 ? - print current values og the CPM Timer registers 4950 b - enable interrupts and start timer 4951 e - stop timer and disable interrupts 4952 q - quit application 4953 4954 => loads 4955 ## Ready for S-Record download ... 4956 ~>examples/timer.srec 4957 1 2 3 4 5 6 7 8 9 10 11 ... 4958 [file transfer complete] 4959 [connected] 4960 ## Start Addr = 0x00040004 4961 4962 => go 40004 4963 ## Starting application at 0x00040004 ... 4964 TIMERS=0xfff00980 4965 Using timer 1 4966 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 4967 4968Hit 'b': 4969 [q, b, e, ?] Set interval 1000000 us 4970 Enabling timer 4971Hit '?': 4972 [q, b, e, ?] ........ 4973 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 4974Hit '?': 4975 [q, b, e, ?] . 4976 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 4977Hit '?': 4978 [q, b, e, ?] . 4979 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 4980Hit '?': 4981 [q, b, e, ?] . 4982 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 4983Hit 'e': 4984 [q, b, e, ?] ...Stopping timer 4985Hit 'q': 4986 [q, b, e, ?] ## Application terminated, rc = 0x0 4987 4988 4989Minicom warning: 4990================ 4991 4992Over time, many people have reported problems when trying to use the 4993"minicom" terminal emulation program for serial download. I (wd) 4994consider minicom to be broken, and recommend not to use it. Under 4995Unix, I recommend to use C-Kermit for general purpose use (and 4996especially for kermit binary protocol download ("loadb" command), and 4997use "cu" for S-Record download ("loads" command). See 4998http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3. 4999for help with kermit. 5000 5001 5002Nevertheless, if you absolutely want to use it try adding this 5003configuration to your "File transfer protocols" section: 5004 5005 Name Program Name U/D FullScr IO-Red. Multi 5006 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 5007 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 5008 5009 5010NetBSD Notes: 5011============= 5012 5013Starting at version 0.9.2, U-Boot supports NetBSD both as host 5014(build U-Boot) and target system (boots NetBSD/mpc8xx). 5015 5016Building requires a cross environment; it is known to work on 5017NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 5018need gmake since the Makefiles are not compatible with BSD make). 5019Note that the cross-powerpc package does not install include files; 5020attempting to build U-Boot will fail because <machine/ansi.h> is 5021missing. This file has to be installed and patched manually: 5022 5023 # cd /usr/pkg/cross/powerpc-netbsd/include 5024 # mkdir powerpc 5025 # ln -s powerpc machine 5026 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 5027 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 5028 5029Native builds *don't* work due to incompatibilities between native 5030and U-Boot include files. 5031 5032Booting assumes that (the first part of) the image booted is a 5033stage-2 loader which in turn loads and then invokes the kernel 5034proper. Loader sources will eventually appear in the NetBSD source 5035tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 5036meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 5037 5038 5039Implementation Internals: 5040========================= 5041 5042The following is not intended to be a complete description of every 5043implementation detail. However, it should help to understand the 5044inner workings of U-Boot and make it easier to port it to custom 5045hardware. 5046 5047 5048Initial Stack, Global Data: 5049--------------------------- 5050 5051The implementation of U-Boot is complicated by the fact that U-Boot 5052starts running out of ROM (flash memory), usually without access to 5053system RAM (because the memory controller is not initialized yet). 5054This means that we don't have writable Data or BSS segments, and BSS 5055is not initialized as zero. To be able to get a C environment working 5056at all, we have to allocate at least a minimal stack. Implementation 5057options for this are defined and restricted by the CPU used: Some CPU 5058models provide on-chip memory (like the IMMR area on MPC8xx and 5059MPC826x processors), on others (parts of) the data cache can be 5060locked as (mis-) used as memory, etc. 5061 5062 Chris Hallinan posted a good summary of these issues to the 5063 U-Boot mailing list: 5064 5065 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 5066 From: "Chris Hallinan" <clh@net1plus.com> 5067 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 5068 ... 5069 5070 Correct me if I'm wrong, folks, but the way I understand it 5071 is this: Using DCACHE as initial RAM for Stack, etc, does not 5072 require any physical RAM backing up the cache. The cleverness 5073 is that the cache is being used as a temporary supply of 5074 necessary storage before the SDRAM controller is setup. It's 5075 beyond the scope of this list to explain the details, but you 5076 can see how this works by studying the cache architecture and 5077 operation in the architecture and processor-specific manuals. 5078 5079 OCM is On Chip Memory, which I believe the 405GP has 4K. It 5080 is another option for the system designer to use as an 5081 initial stack/RAM area prior to SDRAM being available. Either 5082 option should work for you. Using CS 4 should be fine if your 5083 board designers haven't used it for something that would 5084 cause you grief during the initial boot! It is frequently not 5085 used. 5086 5087 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 5088 with your processor/board/system design. The default value 5089 you will find in any recent u-boot distribution in 5090 walnut.h should work for you. I'd set it to a value larger 5091 than your SDRAM module. If you have a 64MB SDRAM module, set 5092 it above 400_0000. Just make sure your board has no resources 5093 that are supposed to respond to that address! That code in 5094 start.S has been around a while and should work as is when 5095 you get the config right. 5096 5097 -Chris Hallinan 5098 DS4.COM, Inc. 5099 5100It is essential to remember this, since it has some impact on the C 5101code for the initialization procedures: 5102 5103* Initialized global data (data segment) is read-only. Do not attempt 5104 to write it. 5105 5106* Do not use any uninitialized global data (or implicitely initialized 5107 as zero data - BSS segment) at all - this is undefined, initiali- 5108 zation is performed later (when relocating to RAM). 5109 5110* Stack space is very limited. Avoid big data buffers or things like 5111 that. 5112 5113Having only the stack as writable memory limits means we cannot use 5114normal global data to share information beween the code. But it 5115turned out that the implementation of U-Boot can be greatly 5116simplified by making a global data structure (gd_t) available to all 5117functions. We could pass a pointer to this data as argument to _all_ 5118functions, but this would bloat the code. Instead we use a feature of 5119the GCC compiler (Global Register Variables) to share the data: we 5120place a pointer (gd) to the global data into a register which we 5121reserve for this purpose. 5122 5123When choosing a register for such a purpose we are restricted by the 5124relevant (E)ABI specifications for the current architecture, and by 5125GCC's implementation. 5126 5127For PowerPC, the following registers have specific use: 5128 R1: stack pointer 5129 R2: reserved for system use 5130 R3-R4: parameter passing and return values 5131 R5-R10: parameter passing 5132 R13: small data area pointer 5133 R30: GOT pointer 5134 R31: frame pointer 5135 5136 (U-Boot also uses R12 as internal GOT pointer. r12 5137 is a volatile register so r12 needs to be reset when 5138 going back and forth between asm and C) 5139 5140 ==> U-Boot will use R2 to hold a pointer to the global data 5141 5142 Note: on PPC, we could use a static initializer (since the 5143 address of the global data structure is known at compile time), 5144 but it turned out that reserving a register results in somewhat 5145 smaller code - although the code savings are not that big (on 5146 average for all boards 752 bytes for the whole U-Boot image, 5147 624 text + 127 data). 5148 5149On Blackfin, the normal C ABI (except for P3) is followed as documented here: 5150 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 5151 5152 ==> U-Boot will use P3 to hold a pointer to the global data 5153 5154On ARM, the following registers are used: 5155 5156 R0: function argument word/integer result 5157 R1-R3: function argument word 5158 R9: GOT pointer 5159 R10: stack limit (used only if stack checking if enabled) 5160 R11: argument (frame) pointer 5161 R12: temporary workspace 5162 R13: stack pointer 5163 R14: link register 5164 R15: program counter 5165 5166 ==> U-Boot will use R8 to hold a pointer to the global data 5167 5168On Nios II, the ABI is documented here: 5169 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 5170 5171 ==> U-Boot will use gp to hold a pointer to the global data 5172 5173 Note: on Nios II, we give "-G0" option to gcc and don't use gp 5174 to access small data sections, so gp is free. 5175 5176On NDS32, the following registers are used: 5177 5178 R0-R1: argument/return 5179 R2-R5: argument 5180 R15: temporary register for assembler 5181 R16: trampoline register 5182 R28: frame pointer (FP) 5183 R29: global pointer (GP) 5184 R30: link register (LP) 5185 R31: stack pointer (SP) 5186 PC: program counter (PC) 5187 5188 ==> U-Boot will use R10 to hold a pointer to the global data 5189 5190NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 5191or current versions of GCC may "optimize" the code too much. 5192 5193Memory Management: 5194------------------ 5195 5196U-Boot runs in system state and uses physical addresses, i.e. the 5197MMU is not used either for address mapping nor for memory protection. 5198 5199The available memory is mapped to fixed addresses using the memory 5200controller. In this process, a contiguous block is formed for each 5201memory type (Flash, SDRAM, SRAM), even when it consists of several 5202physical memory banks. 5203 5204U-Boot is installed in the first 128 kB of the first Flash bank (on 5205TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 5206booting and sizing and initializing DRAM, the code relocates itself 5207to the upper end of DRAM. Immediately below the U-Boot code some 5208memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 5209configuration setting]. Below that, a structure with global Board 5210Info data is placed, followed by the stack (growing downward). 5211 5212Additionally, some exception handler code is copied to the low 8 kB 5213of DRAM (0x00000000 ... 0x00001FFF). 5214 5215So a typical memory configuration with 16 MB of DRAM could look like 5216this: 5217 5218 0x0000 0000 Exception Vector code 5219 : 5220 0x0000 1FFF 5221 0x0000 2000 Free for Application Use 5222 : 5223 : 5224 5225 : 5226 : 5227 0x00FB FF20 Monitor Stack (Growing downward) 5228 0x00FB FFAC Board Info Data and permanent copy of global data 5229 0x00FC 0000 Malloc Arena 5230 : 5231 0x00FD FFFF 5232 0x00FE 0000 RAM Copy of Monitor Code 5233 ... eventually: LCD or video framebuffer 5234 ... eventually: pRAM (Protected RAM - unchanged by reset) 5235 0x00FF FFFF [End of RAM] 5236 5237 5238System Initialization: 5239---------------------- 5240 5241In the reset configuration, U-Boot starts at the reset entry point 5242(on most PowerPC systems at address 0x00000100). Because of the reset 5243configuration for CS0# this is a mirror of the onboard Flash memory. 5244To be able to re-map memory U-Boot then jumps to its link address. 5245To be able to implement the initialization code in C, a (small!) 5246initial stack is set up in the internal Dual Ported RAM (in case CPUs 5247which provide such a feature like MPC8xx or MPC8260), or in a locked 5248part of the data cache. After that, U-Boot initializes the CPU core, 5249the caches and the SIU. 5250 5251Next, all (potentially) available memory banks are mapped using a 5252preliminary mapping. For example, we put them on 512 MB boundaries 5253(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 5254on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 5255programmed for SDRAM access. Using the temporary configuration, a 5256simple memory test is run that determines the size of the SDRAM 5257banks. 5258 5259When there is more than one SDRAM bank, and the banks are of 5260different size, the largest is mapped first. For equal size, the first 5261bank (CS2#) is mapped first. The first mapping is always for address 52620x00000000, with any additional banks following immediately to create 5263contiguous memory starting from 0. 5264 5265Then, the monitor installs itself at the upper end of the SDRAM area 5266and allocates memory for use by malloc() and for the global Board 5267Info data; also, the exception vector code is copied to the low RAM 5268pages, and the final stack is set up. 5269 5270Only after this relocation will you have a "normal" C environment; 5271until that you are restricted in several ways, mostly because you are 5272running from ROM, and because the code will have to be relocated to a 5273new address in RAM. 5274 5275 5276U-Boot Porting Guide: 5277---------------------- 5278 5279[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 5280list, October 2002] 5281 5282 5283int main(int argc, char *argv[]) 5284{ 5285 sighandler_t no_more_time; 5286 5287 signal(SIGALRM, no_more_time); 5288 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 5289 5290 if (available_money > available_manpower) { 5291 Pay consultant to port U-Boot; 5292 return 0; 5293 } 5294 5295 Download latest U-Boot source; 5296 5297 Subscribe to u-boot mailing list; 5298 5299 if (clueless) 5300 email("Hi, I am new to U-Boot, how do I get started?"); 5301 5302 while (learning) { 5303 Read the README file in the top level directory; 5304 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 5305 Read applicable doc/*.README; 5306 Read the source, Luke; 5307 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 5308 } 5309 5310 if (available_money > toLocalCurrency ($2500)) 5311 Buy a BDI3000; 5312 else 5313 Add a lot of aggravation and time; 5314 5315 if (a similar board exists) { /* hopefully... */ 5316 cp -a board/<similar> board/<myboard> 5317 cp include/configs/<similar>.h include/configs/<myboard>.h 5318 } else { 5319 Create your own board support subdirectory; 5320 Create your own board include/configs/<myboard>.h file; 5321 } 5322 Edit new board/<myboard> files 5323 Edit new include/configs/<myboard>.h 5324 5325 while (!accepted) { 5326 while (!running) { 5327 do { 5328 Add / modify source code; 5329 } until (compiles); 5330 Debug; 5331 if (clueless) 5332 email("Hi, I am having problems..."); 5333 } 5334 Send patch file to the U-Boot email list; 5335 if (reasonable critiques) 5336 Incorporate improvements from email list code review; 5337 else 5338 Defend code as written; 5339 } 5340 5341 return 0; 5342} 5343 5344void no_more_time (int sig) 5345{ 5346 hire_a_guru(); 5347} 5348 5349 5350Coding Standards: 5351----------------- 5352 5353All contributions to U-Boot should conform to the Linux kernel 5354coding style; see the file "Documentation/CodingStyle" and the script 5355"scripts/Lindent" in your Linux kernel source directory. 5356 5357Source files originating from a different project (for example the 5358MTD subsystem) are generally exempt from these guidelines and are not 5359reformated to ease subsequent migration to newer versions of those 5360sources. 5361 5362Please note that U-Boot is implemented in C (and to some small parts in 5363Assembler); no C++ is used, so please do not use C++ style comments (//) 5364in your code. 5365 5366Please also stick to the following formatting rules: 5367- remove any trailing white space 5368- use TAB characters for indentation and vertical alignment, not spaces 5369- make sure NOT to use DOS '\r\n' line feeds 5370- do not add more than 2 consecutive empty lines to source files 5371- do not add trailing empty lines to source files 5372 5373Submissions which do not conform to the standards may be returned 5374with a request to reformat the changes. 5375 5376 5377Submitting Patches: 5378------------------- 5379 5380Since the number of patches for U-Boot is growing, we need to 5381establish some rules. Submissions which do not conform to these rules 5382may be rejected, even when they contain important and valuable stuff. 5383 5384Please see http://www.denx.de/wiki/U-Boot/Patches for details. 5385 5386Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 5387see http://lists.denx.de/mailman/listinfo/u-boot 5388 5389When you send a patch, please include the following information with 5390it: 5391 5392* For bug fixes: a description of the bug and how your patch fixes 5393 this bug. Please try to include a way of demonstrating that the 5394 patch actually fixes something. 5395 5396* For new features: a description of the feature and your 5397 implementation. 5398 5399* A CHANGELOG entry as plaintext (separate from the patch) 5400 5401* For major contributions, your entry to the CREDITS file 5402 5403* When you add support for a new board, don't forget to add this 5404 board to the MAINTAINERS file, too. 5405 5406* If your patch adds new configuration options, don't forget to 5407 document these in the README file. 5408 5409* The patch itself. If you are using git (which is *strongly* 5410 recommended) you can easily generate the patch using the 5411 "git format-patch". If you then use "git send-email" to send it to 5412 the U-Boot mailing list, you will avoid most of the common problems 5413 with some other mail clients. 5414 5415 If you cannot use git, use "diff -purN OLD NEW". If your version of 5416 diff does not support these options, then get the latest version of 5417 GNU diff. 5418 5419 The current directory when running this command shall be the parent 5420 directory of the U-Boot source tree (i. e. please make sure that 5421 your patch includes sufficient directory information for the 5422 affected files). 5423 5424 We prefer patches as plain text. MIME attachments are discouraged, 5425 and compressed attachments must not be used. 5426 5427* If one logical set of modifications affects or creates several 5428 files, all these changes shall be submitted in a SINGLE patch file. 5429 5430* Changesets that contain different, unrelated modifications shall be 5431 submitted as SEPARATE patches, one patch per changeset. 5432 5433 5434Notes: 5435 5436* Before sending the patch, run the MAKEALL script on your patched 5437 source tree and make sure that no errors or warnings are reported 5438 for any of the boards. 5439 5440* Keep your modifications to the necessary minimum: A patch 5441 containing several unrelated changes or arbitrary reformats will be 5442 returned with a request to re-formatting / split it. 5443 5444* If you modify existing code, make sure that your new code does not 5445 add to the memory footprint of the code ;-) Small is beautiful! 5446 When adding new features, these should compile conditionally only 5447 (using #ifdef), and the resulting code with the new feature 5448 disabled must not need more memory than the old code without your 5449 modification. 5450 5451* Remember that there is a size limit of 100 kB per message on the 5452 u-boot mailing list. Bigger patches will be moderated. If they are 5453 reasonable and not too big, they will be acknowledged. But patches 5454 bigger than the size limit should be avoided. 5455