1# 2# (C) Copyright 2000 - 2013 3# Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4# 5# SPDX-License-Identifier: GPL-2.0+ 6# 7 8Summary: 9======== 10 11This directory contains the source code for U-Boot, a boot loader for 12Embedded boards based on PowerPC, ARM, MIPS and several other 13processors, which can be installed in a boot ROM and used to 14initialize and test the hardware or to download and run application 15code. 16 17The development of U-Boot is closely related to Linux: some parts of 18the source code originate in the Linux source tree, we have some 19header files in common, and special provision has been made to 20support booting of Linux images. 21 22Some attention has been paid to make this software easily 23configurable and extendable. For instance, all monitor commands are 24implemented with the same call interface, so that it's very easy to 25add new commands. Also, instead of permanently adding rarely used 26code (for instance hardware test utilities) to the monitor, you can 27load and run it dynamically. 28 29 30Status: 31======= 32 33In general, all boards for which a configuration option exists in the 34Makefile have been tested to some extent and can be considered 35"working". In fact, many of them are used in production systems. 36 37In case of problems see the CHANGELOG file to find out who contributed 38the specific port. In addition, there are various MAINTAINERS files 39scattered throughout the U-Boot source identifying the people or 40companies responsible for various boards and subsystems. 41 42Note: As of August, 2010, there is no longer a CHANGELOG file in the 43actual U-Boot source tree; however, it can be created dynamically 44from the Git log using: 45 46 make CHANGELOG 47 48 49Where to get help: 50================== 51 52In case you have questions about, problems with or contributions for 53U-Boot, you should send a message to the U-Boot mailing list at 54<u-boot@lists.denx.de>. There is also an archive of previous traffic 55on the mailing list - please search the archive before asking FAQ's. 56Please see http://lists.denx.de/pipermail/u-boot and 57http://dir.gmane.org/gmane.comp.boot-loaders.u-boot 58 59 60Where to get source code: 61========================= 62 63The U-Boot source code is maintained in the Git repository at 64git://www.denx.de/git/u-boot.git ; you can browse it online at 65http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary 66 67The "snapshot" links on this page allow you to download tarballs of 68any version you might be interested in. Official releases are also 69available for FTP download from the ftp://ftp.denx.de/pub/u-boot/ 70directory. 71 72Pre-built (and tested) images are available from 73ftp://ftp.denx.de/pub/u-boot/images/ 74 75 76Where we come from: 77=================== 78 79- start from 8xxrom sources 80- create PPCBoot project (http://sourceforge.net/projects/ppcboot) 81- clean up code 82- make it easier to add custom boards 83- make it possible to add other [PowerPC] CPUs 84- extend functions, especially: 85 * Provide extended interface to Linux boot loader 86 * S-Record download 87 * network boot 88 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot 89- create ARMBoot project (http://sourceforge.net/projects/armboot) 90- add other CPU families (starting with ARM) 91- create U-Boot project (http://sourceforge.net/projects/u-boot) 92- current project page: see http://www.denx.de/wiki/U-Boot 93 94 95Names and Spelling: 96=================== 97 98The "official" name of this project is "Das U-Boot". The spelling 99"U-Boot" shall be used in all written text (documentation, comments 100in source files etc.). Example: 101 102 This is the README file for the U-Boot project. 103 104File names etc. shall be based on the string "u-boot". Examples: 105 106 include/asm-ppc/u-boot.h 107 108 #include <asm/u-boot.h> 109 110Variable names, preprocessor constants etc. shall be either based on 111the string "u_boot" or on "U_BOOT". Example: 112 113 U_BOOT_VERSION u_boot_logo 114 IH_OS_U_BOOT u_boot_hush_start 115 116 117Versioning: 118=========== 119 120Starting with the release in October 2008, the names of the releases 121were changed from numerical release numbers without deeper meaning 122into a time stamp based numbering. Regular releases are identified by 123names consisting of the calendar year and month of the release date. 124Additional fields (if present) indicate release candidates or bug fix 125releases in "stable" maintenance trees. 126 127Examples: 128 U-Boot v2009.11 - Release November 2009 129 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree 130 U-Boot v2010.09-rc1 - Release candidate 1 for September 2010 release 131 132 133Directory Hierarchy: 134==================== 135 136/arch Architecture specific files 137 /arc Files generic to ARC architecture 138 /arm Files generic to ARM architecture 139 /avr32 Files generic to AVR32 architecture 140 /m68k Files generic to m68k architecture 141 /microblaze Files generic to microblaze architecture 142 /mips Files generic to MIPS architecture 143 /nds32 Files generic to NDS32 architecture 144 /nios2 Files generic to Altera NIOS2 architecture 145 /openrisc Files generic to OpenRISC architecture 146 /powerpc Files generic to PowerPC architecture 147 /sandbox Files generic to HW-independent "sandbox" 148 /sh Files generic to SH architecture 149 /x86 Files generic to x86 architecture 150/api Machine/arch independent API for external apps 151/board Board dependent files 152/cmd U-Boot commands functions 153/common Misc architecture independent functions 154/configs Board default configuration files 155/disk Code for disk drive partition handling 156/doc Documentation (don't expect too much) 157/drivers Commonly used device drivers 158/dts Contains Makefile for building internal U-Boot fdt. 159/examples Example code for standalone applications, etc. 160/fs Filesystem code (cramfs, ext2, jffs2, etc.) 161/include Header Files 162/lib Library routines generic to all architectures 163/Licenses Various license files 164/net Networking code 165/post Power On Self Test 166/scripts Various build scripts and Makefiles 167/test Various unit test files 168/tools Tools to build S-Record or U-Boot images, etc. 169 170Software Configuration: 171======================= 172 173Configuration is usually done using C preprocessor defines; the 174rationale behind that is to avoid dead code whenever possible. 175 176There are two classes of configuration variables: 177 178* Configuration _OPTIONS_: 179 These are selectable by the user and have names beginning with 180 "CONFIG_". 181 182* Configuration _SETTINGS_: 183 These depend on the hardware etc. and should not be meddled with if 184 you don't know what you're doing; they have names beginning with 185 "CONFIG_SYS_". 186 187Previously, all configuration was done by hand, which involved creating 188symbolic links and editing configuration files manually. More recently, 189U-Boot has added the Kbuild infrastructure used by the Linux kernel, 190allowing you to use the "make menuconfig" command to configure your 191build. 192 193 194Selection of Processor Architecture and Board Type: 195--------------------------------------------------- 196 197For all supported boards there are ready-to-use default 198configurations available; just type "make <board_name>_defconfig". 199 200Example: For a TQM823L module type: 201 202 cd u-boot 203 make TQM823L_defconfig 204 205Note: If you're looking for the default configuration file for a board 206you're sure used to be there but is now missing, check the file 207doc/README.scrapyard for a list of no longer supported boards. 208 209Sandbox Environment: 210-------------------- 211 212U-Boot can be built natively to run on a Linux host using the 'sandbox' 213board. This allows feature development which is not board- or architecture- 214specific to be undertaken on a native platform. The sandbox is also used to 215run some of U-Boot's tests. 216 217See board/sandbox/README.sandbox for more details. 218 219 220Board Initialisation Flow: 221-------------------------- 222 223This is the intended start-up flow for boards. This should apply for both 224SPL and U-Boot proper (i.e. they both follow the same rules). 225 226Note: "SPL" stands for "Secondary Program Loader," which is explained in 227more detail later in this file. 228 229At present, SPL mostly uses a separate code path, but the function names 230and roles of each function are the same. Some boards or architectures 231may not conform to this. At least most ARM boards which use 232CONFIG_SPL_FRAMEWORK conform to this. 233 234Execution typically starts with an architecture-specific (and possibly 235CPU-specific) start.S file, such as: 236 237 - arch/arm/cpu/armv7/start.S 238 - arch/powerpc/cpu/mpc83xx/start.S 239 - arch/mips/cpu/start.S 240 241and so on. From there, three functions are called; the purpose and 242limitations of each of these functions are described below. 243 244lowlevel_init(): 245 - purpose: essential init to permit execution to reach board_init_f() 246 - no global_data or BSS 247 - there is no stack (ARMv7 may have one but it will soon be removed) 248 - must not set up SDRAM or use console 249 - must only do the bare minimum to allow execution to continue to 250 board_init_f() 251 - this is almost never needed 252 - return normally from this function 253 254board_init_f(): 255 - purpose: set up the machine ready for running board_init_r(): 256 i.e. SDRAM and serial UART 257 - global_data is available 258 - stack is in SRAM 259 - BSS is not available, so you cannot use global/static variables, 260 only stack variables and global_data 261 262 Non-SPL-specific notes: 263 - dram_init() is called to set up DRAM. If already done in SPL this 264 can do nothing 265 266 SPL-specific notes: 267 - you can override the entire board_init_f() function with your own 268 version as needed. 269 - preloader_console_init() can be called here in extremis 270 - should set up SDRAM, and anything needed to make the UART work 271 - these is no need to clear BSS, it will be done by crt0.S 272 - must return normally from this function (don't call board_init_r() 273 directly) 274 275Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at 276this point the stack and global_data are relocated to below 277CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of 278memory. 279 280board_init_r(): 281 - purpose: main execution, common code 282 - global_data is available 283 - SDRAM is available 284 - BSS is available, all static/global variables can be used 285 - execution eventually continues to main_loop() 286 287 Non-SPL-specific notes: 288 - U-Boot is relocated to the top of memory and is now running from 289 there. 290 291 SPL-specific notes: 292 - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and 293 CONFIG_SPL_STACK_R_ADDR points into SDRAM 294 - preloader_console_init() can be called here - typically this is 295 done by selecting CONFIG_SPL_BOARD_INIT and then supplying a 296 spl_board_init() function containing this call 297 - loads U-Boot or (in falcon mode) Linux 298 299 300 301Configuration Options: 302---------------------- 303 304Configuration depends on the combination of board and CPU type; all 305such information is kept in a configuration file 306"include/configs/<board_name>.h". 307 308Example: For a TQM823L module, all configuration settings are in 309"include/configs/TQM823L.h". 310 311 312Many of the options are named exactly as the corresponding Linux 313kernel configuration options. The intention is to make it easier to 314build a config tool - later. 315 316 317The following options need to be configured: 318 319- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 320 321- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 322 323- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 324 Define exactly one, e.g. CONFIG_ATSTK1002 325 326- Marvell Family Member 327 CONFIG_SYS_MVFS - define it if you want to enable 328 multiple fs option at one time 329 for marvell soc family 330 331- 8xx CPU Options: (if using an MPC8xx CPU) 332 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 333 get_gclk_freq() cannot work 334 e.g. if there is no 32KHz 335 reference PIT/RTC clock 336 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 337 or XTAL/EXTAL) 338 339- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 340 CONFIG_SYS_8xx_CPUCLK_MIN 341 CONFIG_SYS_8xx_CPUCLK_MAX 342 CONFIG_8xx_CPUCLK_DEFAULT 343 See doc/README.MPC866 344 345 CONFIG_SYS_MEASURE_CPUCLK 346 347 Define this to measure the actual CPU clock instead 348 of relying on the correctness of the configured 349 values. Mostly useful for board bringup to make sure 350 the PLL is locked at the intended frequency. Note 351 that this requires a (stable) reference clock (32 kHz 352 RTC clock or CONFIG_SYS_8XX_XIN) 353 354 CONFIG_SYS_DELAYED_ICACHE 355 356 Define this option if you want to enable the 357 ICache only when Code runs from RAM. 358 359- 85xx CPU Options: 360 CONFIG_SYS_PPC64 361 362 Specifies that the core is a 64-bit PowerPC implementation (implements 363 the "64" category of the Power ISA). This is necessary for ePAPR 364 compliance, among other possible reasons. 365 366 CONFIG_SYS_FSL_TBCLK_DIV 367 368 Defines the core time base clock divider ratio compared to the 369 system clock. On most PQ3 devices this is 8, on newer QorIQ 370 devices it can be 16 or 32. The ratio varies from SoC to Soc. 371 372 CONFIG_SYS_FSL_PCIE_COMPAT 373 374 Defines the string to utilize when trying to match PCIe device 375 tree nodes for the given platform. 376 377 CONFIG_SYS_FSL_ERRATUM_A004510 378 379 Enables a workaround for erratum A004510. If set, 380 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and 381 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set. 382 383 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV 384 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional) 385 386 Defines one or two SoC revisions (low 8 bits of SVR) 387 for which the A004510 workaround should be applied. 388 389 The rest of SVR is either not relevant to the decision 390 of whether the erratum is present (e.g. p2040 versus 391 p2041) or is implied by the build target, which controls 392 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set. 393 394 See Freescale App Note 4493 for more information about 395 this erratum. 396 397 CONFIG_A003399_NOR_WORKAROUND 398 Enables a workaround for IFC erratum A003399. It is only 399 required during NOR boot. 400 401 CONFIG_A008044_WORKAROUND 402 Enables a workaround for T1040/T1042 erratum A008044. It is only 403 required during NAND boot and valid for Rev 1.0 SoC revision 404 405 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 406 407 This is the value to write into CCSR offset 0x18600 408 according to the A004510 workaround. 409 410 CONFIG_SYS_FSL_DSP_DDR_ADDR 411 This value denotes start offset of DDR memory which is 412 connected exclusively to the DSP cores. 413 414 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR 415 This value denotes start offset of M2 memory 416 which is directly connected to the DSP core. 417 418 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR 419 This value denotes start offset of M3 memory which is directly 420 connected to the DSP core. 421 422 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT 423 This value denotes start offset of DSP CCSR space. 424 425 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK 426 Single Source Clock is clocking mode present in some of FSL SoC's. 427 In this mode, a single differential clock is used to supply 428 clocks to the sysclock, ddrclock and usbclock. 429 430 CONFIG_SYS_CPC_REINIT_F 431 This CONFIG is defined when the CPC is configured as SRAM at the 432 time of U-Boot entry and is required to be re-initialized. 433 434 CONFIG_DEEP_SLEEP 435 Indicates this SoC supports deep sleep feature. If deep sleep is 436 supported, core will start to execute uboot when wakes up. 437 438- Generic CPU options: 439 CONFIG_SYS_GENERIC_GLOBAL_DATA 440 Defines global data is initialized in generic board board_init_f(). 441 If this macro is defined, global data is created and cleared in 442 generic board board_init_f(). Without this macro, architecture/board 443 should initialize global data before calling board_init_f(). 444 445 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN 446 447 Defines the endianess of the CPU. Implementation of those 448 values is arch specific. 449 450 CONFIG_SYS_FSL_DDR 451 Freescale DDR driver in use. This type of DDR controller is 452 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core 453 SoCs. 454 455 CONFIG_SYS_FSL_DDR_ADDR 456 Freescale DDR memory-mapped register base. 457 458 CONFIG_SYS_FSL_DDR_EMU 459 Specify emulator support for DDR. Some DDR features such as 460 deskew training are not available. 461 462 CONFIG_SYS_FSL_DDRC_GEN1 463 Freescale DDR1 controller. 464 465 CONFIG_SYS_FSL_DDRC_GEN2 466 Freescale DDR2 controller. 467 468 CONFIG_SYS_FSL_DDRC_GEN3 469 Freescale DDR3 controller. 470 471 CONFIG_SYS_FSL_DDRC_GEN4 472 Freescale DDR4 controller. 473 474 CONFIG_SYS_FSL_DDRC_ARM_GEN3 475 Freescale DDR3 controller for ARM-based SoCs. 476 477 CONFIG_SYS_FSL_DDR1 478 Board config to use DDR1. It can be enabled for SoCs with 479 Freescale DDR1 or DDR2 controllers, depending on the board 480 implemetation. 481 482 CONFIG_SYS_FSL_DDR2 483 Board config to use DDR2. It can be enabled for SoCs with 484 Freescale DDR2 or DDR3 controllers, depending on the board 485 implementation. 486 487 CONFIG_SYS_FSL_DDR3 488 Board config to use DDR3. It can be enabled for SoCs with 489 Freescale DDR3 or DDR3L controllers. 490 491 CONFIG_SYS_FSL_DDR3L 492 Board config to use DDR3L. It can be enabled for SoCs with 493 DDR3L controllers. 494 495 CONFIG_SYS_FSL_DDR4 496 Board config to use DDR4. It can be enabled for SoCs with 497 DDR4 controllers. 498 499 CONFIG_SYS_FSL_IFC_BE 500 Defines the IFC controller register space as Big Endian 501 502 CONFIG_SYS_FSL_IFC_LE 503 Defines the IFC controller register space as Little Endian 504 505 CONFIG_SYS_FSL_IFC_CLK_DIV 506 Defines divider of platform clock(clock input to IFC controller). 507 508 CONFIG_SYS_FSL_LBC_CLK_DIV 509 Defines divider of platform clock(clock input to eLBC controller). 510 511 CONFIG_SYS_FSL_PBL_PBI 512 It enables addition of RCW (Power on reset configuration) in built image. 513 Please refer doc/README.pblimage for more details 514 515 CONFIG_SYS_FSL_PBL_RCW 516 It adds PBI(pre-boot instructions) commands in u-boot build image. 517 PBI commands can be used to configure SoC before it starts the execution. 518 Please refer doc/README.pblimage for more details 519 520 CONFIG_SPL_FSL_PBL 521 It adds a target to create boot binary having SPL binary in PBI format 522 concatenated with u-boot binary. 523 524 CONFIG_SYS_FSL_DDR_BE 525 Defines the DDR controller register space as Big Endian 526 527 CONFIG_SYS_FSL_DDR_LE 528 Defines the DDR controller register space as Little Endian 529 530 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY 531 Physical address from the view of DDR controllers. It is the 532 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But 533 it could be different for ARM SoCs. 534 535 CONFIG_SYS_FSL_DDR_INTLV_256B 536 DDR controller interleaving on 256-byte. This is a special 537 interleaving mode, handled by Dickens for Freescale layerscape 538 SoCs with ARM core. 539 540 CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS 541 Number of controllers used as main memory. 542 543 CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS 544 Number of controllers used for other than main memory. 545 546 CONFIG_SYS_FSL_HAS_DP_DDR 547 Defines the SoC has DP-DDR used for DPAA. 548 549 CONFIG_SYS_FSL_SEC_BE 550 Defines the SEC controller register space as Big Endian 551 552 CONFIG_SYS_FSL_SEC_LE 553 Defines the SEC controller register space as Little Endian 554 555- MIPS CPU options: 556 CONFIG_SYS_INIT_SP_OFFSET 557 558 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack 559 pointer. This is needed for the temporary stack before 560 relocation. 561 562 CONFIG_SYS_MIPS_CACHE_MODE 563 564 Cache operation mode for the MIPS CPU. 565 See also arch/mips/include/asm/mipsregs.h. 566 Possible values are: 567 CONF_CM_CACHABLE_NO_WA 568 CONF_CM_CACHABLE_WA 569 CONF_CM_UNCACHED 570 CONF_CM_CACHABLE_NONCOHERENT 571 CONF_CM_CACHABLE_CE 572 CONF_CM_CACHABLE_COW 573 CONF_CM_CACHABLE_CUW 574 CONF_CM_CACHABLE_ACCELERATED 575 576 CONFIG_SYS_XWAY_EBU_BOOTCFG 577 578 Special option for Lantiq XWAY SoCs for booting from NOR flash. 579 See also arch/mips/cpu/mips32/start.S. 580 581 CONFIG_XWAY_SWAP_BYTES 582 583 Enable compilation of tools/xway-swap-bytes needed for Lantiq 584 XWAY SoCs for booting from NOR flash. The U-Boot image needs to 585 be swapped if a flash programmer is used. 586 587- ARM options: 588 CONFIG_SYS_EXCEPTION_VECTORS_HIGH 589 590 Select high exception vectors of the ARM core, e.g., do not 591 clear the V bit of the c1 register of CP15. 592 593 COUNTER_FREQUENCY 594 Generic timer clock source frequency. 595 596 COUNTER_FREQUENCY_REAL 597 Generic timer clock source frequency if the real clock is 598 different from COUNTER_FREQUENCY, and can only be determined 599 at run time. 600 601- Tegra SoC options: 602 CONFIG_TEGRA_SUPPORT_NON_SECURE 603 604 Support executing U-Boot in non-secure (NS) mode. Certain 605 impossible actions will be skipped if the CPU is in NS mode, 606 such as ARM architectural timer initialization. 607 608- Linux Kernel Interface: 609 CONFIG_CLOCKS_IN_MHZ 610 611 U-Boot stores all clock information in Hz 612 internally. For binary compatibility with older Linux 613 kernels (which expect the clocks passed in the 614 bd_info data to be in MHz) the environment variable 615 "clocks_in_mhz" can be defined so that U-Boot 616 converts clock data to MHZ before passing it to the 617 Linux kernel. 618 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 619 "clocks_in_mhz=1" is automatically included in the 620 default environment. 621 622 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 623 624 When transferring memsize parameter to Linux, some versions 625 expect it to be in bytes, others in MB. 626 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 627 628 CONFIG_OF_LIBFDT 629 630 New kernel versions are expecting firmware settings to be 631 passed using flattened device trees (based on open firmware 632 concepts). 633 634 CONFIG_OF_LIBFDT 635 * New libfdt-based support 636 * Adds the "fdt" command 637 * The bootm command automatically updates the fdt 638 639 OF_CPU - The proper name of the cpus node (only required for 640 MPC512X and MPC5xxx based boards). 641 OF_SOC - The proper name of the soc node (only required for 642 MPC512X and MPC5xxx based boards). 643 OF_TBCLK - The timebase frequency. 644 OF_STDOUT_PATH - The path to the console device 645 646 boards with QUICC Engines require OF_QE to set UCC MAC 647 addresses 648 649 CONFIG_OF_BOARD_SETUP 650 651 Board code has addition modification that it wants to make 652 to the flat device tree before handing it off to the kernel 653 654 CONFIG_OF_SYSTEM_SETUP 655 656 Other code has addition modification that it wants to make 657 to the flat device tree before handing it off to the kernel. 658 This causes ft_system_setup() to be called before booting 659 the kernel. 660 661 CONFIG_OF_IDE_FIXUP 662 663 U-Boot can detect if an IDE device is present or not. 664 If not, and this new config option is activated, U-Boot 665 removes the ATA node from the DTS before booting Linux, 666 so the Linux IDE driver does not probe the device and 667 crash. This is needed for buggy hardware (uc101) where 668 no pull down resistor is connected to the signal IDE5V_DD7. 669 670 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 671 672 This setting is mandatory for all boards that have only one 673 machine type and must be used to specify the machine type 674 number as it appears in the ARM machine registry 675 (see http://www.arm.linux.org.uk/developer/machines/). 676 Only boards that have multiple machine types supported 677 in a single configuration file and the machine type is 678 runtime discoverable, do not have to use this setting. 679 680- vxWorks boot parameters: 681 682 bootvx constructs a valid bootline using the following 683 environments variables: bootdev, bootfile, ipaddr, netmask, 684 serverip, gatewayip, hostname, othbootargs. 685 It loads the vxWorks image pointed bootfile. 686 687 Note: If a "bootargs" environment is defined, it will overwride 688 the defaults discussed just above. 689 690- Cache Configuration: 691 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 692 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 693 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 694 695- Cache Configuration for ARM: 696 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 697 controller 698 CONFIG_SYS_PL310_BASE - Physical base address of PL310 699 controller register space 700 701- Serial Ports: 702 CONFIG_PL010_SERIAL 703 704 Define this if you want support for Amba PrimeCell PL010 UARTs. 705 706 CONFIG_PL011_SERIAL 707 708 Define this if you want support for Amba PrimeCell PL011 UARTs. 709 710 CONFIG_PL011_CLOCK 711 712 If you have Amba PrimeCell PL011 UARTs, set this variable to 713 the clock speed of the UARTs. 714 715 CONFIG_PL01x_PORTS 716 717 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 718 define this to a list of base addresses for each (supported) 719 port. See e.g. include/configs/versatile.h 720 721 CONFIG_SERIAL_HW_FLOW_CONTROL 722 723 Define this variable to enable hw flow control in serial driver. 724 Current user of this option is drivers/serial/nsl16550.c driver 725 726- Console Interface: 727 Depending on board, define exactly one serial port 728 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 729 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 730 console by defining CONFIG_8xx_CONS_NONE 731 732 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 733 port routines must be defined elsewhere 734 (i.e. serial_init(), serial_getc(), ...) 735 736- Console Baudrate: 737 CONFIG_BAUDRATE - in bps 738 Select one of the baudrates listed in 739 CONFIG_SYS_BAUDRATE_TABLE, see below. 740 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 741 742- Console Rx buffer length 743 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 744 the maximum receive buffer length for the SMC. 745 This option is actual only for 82xx and 8xx possible. 746 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 747 must be defined, to setup the maximum idle timeout for 748 the SMC. 749 750- Autoboot Command: 751 CONFIG_BOOTCOMMAND 752 Only needed when CONFIG_BOOTDELAY is enabled; 753 define a command string that is automatically executed 754 when no character is read on the console interface 755 within "Boot Delay" after reset. 756 757 CONFIG_BOOTARGS 758 This can be used to pass arguments to the bootm 759 command. The value of CONFIG_BOOTARGS goes into the 760 environment value "bootargs". 761 762 CONFIG_RAMBOOT and CONFIG_NFSBOOT 763 The value of these goes into the environment as 764 "ramboot" and "nfsboot" respectively, and can be used 765 as a convenience, when switching between booting from 766 RAM and NFS. 767 768- Bootcount: 769 CONFIG_BOOTCOUNT_LIMIT 770 Implements a mechanism for detecting a repeating reboot 771 cycle, see: 772 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit 773 774 CONFIG_BOOTCOUNT_ENV 775 If no softreset save registers are found on the hardware 776 "bootcount" is stored in the environment. To prevent a 777 saveenv on all reboots, the environment variable 778 "upgrade_available" is used. If "upgrade_available" is 779 0, "bootcount" is always 0, if "upgrade_available" is 780 1 "bootcount" is incremented in the environment. 781 So the Userspace Applikation must set the "upgrade_available" 782 and "bootcount" variable to 0, if a boot was successfully. 783 784- Pre-Boot Commands: 785 CONFIG_PREBOOT 786 787 When this option is #defined, the existence of the 788 environment variable "preboot" will be checked 789 immediately before starting the CONFIG_BOOTDELAY 790 countdown and/or running the auto-boot command resp. 791 entering interactive mode. 792 793 This feature is especially useful when "preboot" is 794 automatically generated or modified. For an example 795 see the LWMON board specific code: here "preboot" is 796 modified when the user holds down a certain 797 combination of keys on the (special) keyboard when 798 booting the systems 799 800- Serial Download Echo Mode: 801 CONFIG_LOADS_ECHO 802 If defined to 1, all characters received during a 803 serial download (using the "loads" command) are 804 echoed back. This might be needed by some terminal 805 emulations (like "cu"), but may as well just take 806 time on others. This setting #define's the initial 807 value of the "loads_echo" environment variable. 808 809- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 810 CONFIG_KGDB_BAUDRATE 811 Select one of the baudrates listed in 812 CONFIG_SYS_BAUDRATE_TABLE, see below. 813 814- Monitor Functions: 815 Monitor commands can be included or excluded 816 from the build by using the #include files 817 <config_cmd_all.h> and #undef'ing unwanted 818 commands, or adding #define's for wanted commands. 819 820 The default command configuration includes all commands 821 except those marked below with a "*". 822 823 CONFIG_CMD_AES AES 128 CBC encrypt/decrypt 824 CONFIG_CMD_ASKENV * ask for env variable 825 CONFIG_CMD_BDI bdinfo 826 CONFIG_CMD_BOOTD bootd 827 CONFIG_CMD_BOOTI * ARM64 Linux kernel Image support 828 CONFIG_CMD_CACHE * icache, dcache 829 CONFIG_CMD_CONSOLE coninfo 830 CONFIG_CMD_CRC32 * crc32 831 CONFIG_CMD_DHCP * DHCP support 832 CONFIG_CMD_DIAG * Diagnostics 833 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands 834 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command 835 CONFIG_CMD_DTT * Digital Therm and Thermostat 836 CONFIG_CMD_ECHO echo arguments 837 CONFIG_CMD_EDITENV edit env variable 838 CONFIG_CMD_EEPROM * EEPROM read/write support 839 CONFIG_CMD_EEPROM_LAYOUT* EEPROM layout aware commands 840 CONFIG_CMD_ELF * bootelf, bootvx 841 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks 842 CONFIG_CMD_ENV_FLAGS * display details about env flags 843 CONFIG_CMD_ENV_EXISTS * check existence of env variable 844 CONFIG_CMD_EXPORTENV * export the environment 845 CONFIG_CMD_EXT2 * ext2 command support 846 CONFIG_CMD_EXT4 * ext4 command support 847 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls) 848 that work for multiple fs types 849 CONFIG_CMD_FS_UUID * Look up a filesystem UUID 850 CONFIG_CMD_SAVEENV saveenv 851 CONFIG_CMD_FDC * Floppy Disk Support 852 CONFIG_CMD_FAT * FAT command support 853 CONFIG_CMD_FLASH flinfo, erase, protect 854 CONFIG_CMD_FPGA FPGA device initialization support 855 CONFIG_CMD_FUSE * Device fuse support 856 CONFIG_CMD_GETTIME * Get time since boot 857 CONFIG_CMD_GO * the 'go' command (exec code) 858 CONFIG_CMD_GREPENV * search environment 859 CONFIG_CMD_HASH * calculate hash / digest 860 CONFIG_CMD_I2C * I2C serial bus support 861 CONFIG_CMD_IDE * IDE harddisk support 862 CONFIG_CMD_IMI iminfo 863 CONFIG_CMD_IMLS List all images found in NOR flash 864 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash 865 CONFIG_CMD_IMMAP * IMMR dump support 866 CONFIG_CMD_IOTRACE * I/O tracing for debugging 867 CONFIG_CMD_IMPORTENV * import an environment 868 CONFIG_CMD_INI * import data from an ini file into the env 869 CONFIG_CMD_IRQ * irqinfo 870 CONFIG_CMD_ITEST Integer/string test of 2 values 871 CONFIG_CMD_JFFS2 * JFFS2 Support 872 CONFIG_CMD_KGDB * kgdb 873 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader) 874 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration 875 (169.254.*.*) 876 CONFIG_CMD_LOADB loadb 877 CONFIG_CMD_LOADS loads 878 CONFIG_CMD_MD5SUM * print md5 message digest 879 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 880 CONFIG_CMD_MEMINFO * Display detailed memory information 881 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 882 loop, loopw 883 CONFIG_CMD_MEMTEST * mtest 884 CONFIG_CMD_MISC Misc functions like sleep etc 885 CONFIG_CMD_MMC * MMC memory mapped support 886 CONFIG_CMD_MII * MII utility commands 887 CONFIG_CMD_MTDPARTS * MTD partition support 888 CONFIG_CMD_NAND * NAND support 889 CONFIG_CMD_NET bootp, tftpboot, rarpboot 890 CONFIG_CMD_NFS NFS support 891 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 892 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 893 CONFIG_CMD_PCI * pciinfo 894 CONFIG_CMD_PCMCIA * PCMCIA support 895 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 896 host 897 CONFIG_CMD_PORTIO * Port I/O 898 CONFIG_CMD_READ * Read raw data from partition 899 CONFIG_CMD_REGINFO * Register dump 900 CONFIG_CMD_RUN run command in env variable 901 CONFIG_CMD_SANDBOX * sb command to access sandbox features 902 CONFIG_CMD_SAVES * save S record dump 903 CONFIG_SCSI * SCSI Support 904 CONFIG_CMD_SDRAM * print SDRAM configuration information 905 (requires CONFIG_CMD_I2C) 906 CONFIG_CMD_SETGETDCR Support for DCR Register access 907 (4xx only) 908 CONFIG_CMD_SF * Read/write/erase SPI NOR flash 909 CONFIG_CMD_SHA1SUM * print sha1 memory digest 910 (requires CONFIG_CMD_MEMORY) 911 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x 912 CONFIG_CMD_SOURCE "source" command Support 913 CONFIG_CMD_SPI * SPI serial bus support 914 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 915 CONFIG_CMD_TFTPPUT * TFTP put command (upload) 916 CONFIG_CMD_TIME * run command and report execution time (ARM specific) 917 CONFIG_CMD_TIMER * access to the system tick timer 918 CONFIG_CMD_USB * USB support 919 CONFIG_CMD_CDP * Cisco Discover Protocol support 920 CONFIG_CMD_MFSL * Microblaze FSL support 921 CONFIG_CMD_XIMG Load part of Multi Image 922 CONFIG_CMD_UUID * Generate random UUID or GUID string 923 924 EXAMPLE: If you want all functions except of network 925 support you can write: 926 927 #include "config_cmd_all.h" 928 #undef CONFIG_CMD_NET 929 930 Other Commands: 931 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 932 933 Note: Don't enable the "icache" and "dcache" commands 934 (configuration option CONFIG_CMD_CACHE) unless you know 935 what you (and your U-Boot users) are doing. Data 936 cache cannot be enabled on systems like the 8xx or 937 8260 (where accesses to the IMMR region must be 938 uncached), and it cannot be disabled on all other 939 systems where we (mis-) use the data cache to hold an 940 initial stack and some data. 941 942 943 XXX - this list needs to get updated! 944 945- Removal of commands 946 If no commands are needed to boot, you can disable 947 CONFIG_CMDLINE to remove them. In this case, the command line 948 will not be available, and when U-Boot wants to execute the 949 boot command (on start-up) it will call board_run_command() 950 instead. This can reduce image size significantly for very 951 simple boot procedures. 952 953- Regular expression support: 954 CONFIG_REGEX 955 If this variable is defined, U-Boot is linked against 956 the SLRE (Super Light Regular Expression) library, 957 which adds regex support to some commands, as for 958 example "env grep" and "setexpr". 959 960- Device tree: 961 CONFIG_OF_CONTROL 962 If this variable is defined, U-Boot will use a device tree 963 to configure its devices, instead of relying on statically 964 compiled #defines in the board file. This option is 965 experimental and only available on a few boards. The device 966 tree is available in the global data as gd->fdt_blob. 967 968 U-Boot needs to get its device tree from somewhere. This can 969 be done using one of the three options below: 970 971 CONFIG_OF_EMBED 972 If this variable is defined, U-Boot will embed a device tree 973 binary in its image. This device tree file should be in the 974 board directory and called <soc>-<board>.dts. The binary file 975 is then picked up in board_init_f() and made available through 976 the global data structure as gd->blob. 977 978 CONFIG_OF_SEPARATE 979 If this variable is defined, U-Boot will build a device tree 980 binary. It will be called u-boot.dtb. Architecture-specific 981 code will locate it at run-time. Generally this works by: 982 983 cat u-boot.bin u-boot.dtb >image.bin 984 985 and in fact, U-Boot does this for you, creating a file called 986 u-boot-dtb.bin which is useful in the common case. You can 987 still use the individual files if you need something more 988 exotic. 989 990 CONFIG_OF_BOARD 991 If this variable is defined, U-Boot will use the device tree 992 provided by the board at runtime instead of embedding one with 993 the image. Only boards defining board_fdt_blob_setup() support 994 this option (see include/fdtdec.h file). 995 996- Watchdog: 997 CONFIG_WATCHDOG 998 If this variable is defined, it enables watchdog 999 support for the SoC. There must be support in the SoC 1000 specific code for a watchdog. For the 8xx and 8260 1001 CPUs, the SIU Watchdog feature is enabled in the SYPCR 1002 register. When supported for a specific SoC is 1003 available, then no further board specific code should 1004 be needed to use it. 1005 1006 CONFIG_HW_WATCHDOG 1007 When using a watchdog circuitry external to the used 1008 SoC, then define this variable and provide board 1009 specific code for the "hw_watchdog_reset" function. 1010 1011 CONFIG_AT91_HW_WDT_TIMEOUT 1012 specify the timeout in seconds. default 2 seconds. 1013 1014- U-Boot Version: 1015 CONFIG_VERSION_VARIABLE 1016 If this variable is defined, an environment variable 1017 named "ver" is created by U-Boot showing the U-Boot 1018 version as printed by the "version" command. 1019 Any change to this variable will be reverted at the 1020 next reset. 1021 1022- Real-Time Clock: 1023 1024 When CONFIG_CMD_DATE is selected, the type of the RTC 1025 has to be selected, too. Define exactly one of the 1026 following options: 1027 1028 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 1029 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 1030 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 1031 CONFIG_RTC_MC146818 - use MC146818 RTC 1032 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 1033 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 1034 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 1035 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC 1036 CONFIG_RTC_DS164x - use Dallas DS164x RTC 1037 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 1038 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 1039 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 1040 CONFIG_SYS_RV3029_TCR - enable trickle charger on 1041 RV3029 RTC. 1042 1043 Note that if the RTC uses I2C, then the I2C interface 1044 must also be configured. See I2C Support, below. 1045 1046- GPIO Support: 1047 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 1048 1049 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 1050 chip-ngpio pairs that tell the PCA953X driver the number of 1051 pins supported by a particular chip. 1052 1053 Note that if the GPIO device uses I2C, then the I2C interface 1054 must also be configured. See I2C Support, below. 1055 1056- I/O tracing: 1057 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O 1058 accesses and can checksum them or write a list of them out 1059 to memory. See the 'iotrace' command for details. This is 1060 useful for testing device drivers since it can confirm that 1061 the driver behaves the same way before and after a code 1062 change. Currently this is supported on sandbox and arm. To 1063 add support for your architecture, add '#include <iotrace.h>' 1064 to the bottom of arch/<arch>/include/asm/io.h and test. 1065 1066 Example output from the 'iotrace stats' command is below. 1067 Note that if the trace buffer is exhausted, the checksum will 1068 still continue to operate. 1069 1070 iotrace is enabled 1071 Start: 10000000 (buffer start address) 1072 Size: 00010000 (buffer size) 1073 Offset: 00000120 (current buffer offset) 1074 Output: 10000120 (start + offset) 1075 Count: 00000018 (number of trace records) 1076 CRC32: 9526fb66 (CRC32 of all trace records) 1077 1078- Timestamp Support: 1079 1080 When CONFIG_TIMESTAMP is selected, the timestamp 1081 (date and time) of an image is printed by image 1082 commands like bootm or iminfo. This option is 1083 automatically enabled when you select CONFIG_CMD_DATE . 1084 1085- Partition Labels (disklabels) Supported: 1086 Zero or more of the following: 1087 CONFIG_MAC_PARTITION Apple's MacOS partition table. 1088 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the 1089 Intel architecture, USB sticks, etc. 1090 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc. 1091 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the 1092 bootloader. Note 2TB partition limit; see 1093 disk/part_efi.c 1094 CONFIG_MTD_PARTITIONS Memory Technology Device partition table. 1095 1096 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 1097 CONFIG_SCSI) you must configure support for at 1098 least one non-MTD partition type as well. 1099 1100- IDE Reset method: 1101 CONFIG_IDE_RESET_ROUTINE - this is defined in several 1102 board configurations files but used nowhere! 1103 1104 CONFIG_IDE_RESET - is this is defined, IDE Reset will 1105 be performed by calling the function 1106 ide_set_reset(int reset) 1107 which has to be defined in a board specific file 1108 1109- ATAPI Support: 1110 CONFIG_ATAPI 1111 1112 Set this to enable ATAPI support. 1113 1114- LBA48 Support 1115 CONFIG_LBA48 1116 1117 Set this to enable support for disks larger than 137GB 1118 Also look at CONFIG_SYS_64BIT_LBA. 1119 Whithout these , LBA48 support uses 32bit variables and will 'only' 1120 support disks up to 2.1TB. 1121 1122 CONFIG_SYS_64BIT_LBA: 1123 When enabled, makes the IDE subsystem use 64bit sector addresses. 1124 Default is 32bit. 1125 1126- SCSI Support: 1127 At the moment only there is only support for the 1128 SYM53C8XX SCSI controller; define 1129 CONFIG_SCSI_SYM53C8XX to enable it. 1130 1131 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 1132 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 1133 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 1134 maximum numbers of LUNs, SCSI ID's and target 1135 devices. 1136 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 1137 1138 The environment variable 'scsidevs' is set to the number of 1139 SCSI devices found during the last scan. 1140 1141- NETWORK Support (PCI): 1142 CONFIG_E1000 1143 Support for Intel 8254x/8257x gigabit chips. 1144 1145 CONFIG_E1000_SPI 1146 Utility code for direct access to the SPI bus on Intel 8257x. 1147 This does not do anything useful unless you set at least one 1148 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 1149 1150 CONFIG_E1000_SPI_GENERIC 1151 Allow generic access to the SPI bus on the Intel 8257x, for 1152 example with the "sspi" command. 1153 1154 CONFIG_CMD_E1000 1155 Management command for E1000 devices. When used on devices 1156 with SPI support you can reprogram the EEPROM from U-Boot. 1157 1158 CONFIG_EEPRO100 1159 Support for Intel 82557/82559/82559ER chips. 1160 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 1161 write routine for first time initialisation. 1162 1163 CONFIG_TULIP 1164 Support for Digital 2114x chips. 1165 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 1166 modem chip initialisation (KS8761/QS6611). 1167 1168 CONFIG_NATSEMI 1169 Support for National dp83815 chips. 1170 1171 CONFIG_NS8382X 1172 Support for National dp8382[01] gigabit chips. 1173 1174- NETWORK Support (other): 1175 1176 CONFIG_DRIVER_AT91EMAC 1177 Support for AT91RM9200 EMAC. 1178 1179 CONFIG_RMII 1180 Define this to use reduced MII inteface 1181 1182 CONFIG_DRIVER_AT91EMAC_QUIET 1183 If this defined, the driver is quiet. 1184 The driver doen't show link status messages. 1185 1186 CONFIG_CALXEDA_XGMAC 1187 Support for the Calxeda XGMAC device 1188 1189 CONFIG_LAN91C96 1190 Support for SMSC's LAN91C96 chips. 1191 1192 CONFIG_LAN91C96_USE_32_BIT 1193 Define this to enable 32 bit addressing 1194 1195 CONFIG_SMC91111 1196 Support for SMSC's LAN91C111 chip 1197 1198 CONFIG_SMC91111_BASE 1199 Define this to hold the physical address 1200 of the device (I/O space) 1201 1202 CONFIG_SMC_USE_32_BIT 1203 Define this if data bus is 32 bits 1204 1205 CONFIG_SMC_USE_IOFUNCS 1206 Define this to use i/o functions instead of macros 1207 (some hardware wont work with macros) 1208 1209 CONFIG_DRIVER_TI_EMAC 1210 Support for davinci emac 1211 1212 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1213 Define this if you have more then 3 PHYs. 1214 1215 CONFIG_FTGMAC100 1216 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1217 1218 CONFIG_FTGMAC100_EGIGA 1219 Define this to use GE link update with gigabit PHY. 1220 Define this if FTGMAC100 is connected to gigabit PHY. 1221 If your system has 10/100 PHY only, it might not occur 1222 wrong behavior. Because PHY usually return timeout or 1223 useless data when polling gigabit status and gigabit 1224 control registers. This behavior won't affect the 1225 correctnessof 10/100 link speed update. 1226 1227 CONFIG_SMC911X 1228 Support for SMSC's LAN911x and LAN921x chips 1229 1230 CONFIG_SMC911X_BASE 1231 Define this to hold the physical address 1232 of the device (I/O space) 1233 1234 CONFIG_SMC911X_32_BIT 1235 Define this if data bus is 32 bits 1236 1237 CONFIG_SMC911X_16_BIT 1238 Define this if data bus is 16 bits. If your processor 1239 automatically converts one 32 bit word to two 16 bit 1240 words you may also try CONFIG_SMC911X_32_BIT. 1241 1242 CONFIG_SH_ETHER 1243 Support for Renesas on-chip Ethernet controller 1244 1245 CONFIG_SH_ETHER_USE_PORT 1246 Define the number of ports to be used 1247 1248 CONFIG_SH_ETHER_PHY_ADDR 1249 Define the ETH PHY's address 1250 1251 CONFIG_SH_ETHER_CACHE_WRITEBACK 1252 If this option is set, the driver enables cache flush. 1253 1254- PWM Support: 1255 CONFIG_PWM_IMX 1256 Support for PWM module on the imx6. 1257 1258- TPM Support: 1259 CONFIG_TPM 1260 Support TPM devices. 1261 1262 CONFIG_TPM_TIS_INFINEON 1263 Support for Infineon i2c bus TPM devices. Only one device 1264 per system is supported at this time. 1265 1266 CONFIG_TPM_TIS_I2C_BURST_LIMITATION 1267 Define the burst count bytes upper limit 1268 1269 CONFIG_TPM_ST33ZP24 1270 Support for STMicroelectronics TPM devices. Requires DM_TPM support. 1271 1272 CONFIG_TPM_ST33ZP24_I2C 1273 Support for STMicroelectronics ST33ZP24 I2C devices. 1274 Requires TPM_ST33ZP24 and I2C. 1275 1276 CONFIG_TPM_ST33ZP24_SPI 1277 Support for STMicroelectronics ST33ZP24 SPI devices. 1278 Requires TPM_ST33ZP24 and SPI. 1279 1280 CONFIG_TPM_ATMEL_TWI 1281 Support for Atmel TWI TPM device. Requires I2C support. 1282 1283 CONFIG_TPM_TIS_LPC 1284 Support for generic parallel port TPM devices. Only one device 1285 per system is supported at this time. 1286 1287 CONFIG_TPM_TIS_BASE_ADDRESS 1288 Base address where the generic TPM device is mapped 1289 to. Contemporary x86 systems usually map it at 1290 0xfed40000. 1291 1292 CONFIG_CMD_TPM 1293 Add tpm monitor functions. 1294 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also 1295 provides monitor access to authorized functions. 1296 1297 CONFIG_TPM 1298 Define this to enable the TPM support library which provides 1299 functional interfaces to some TPM commands. 1300 Requires support for a TPM device. 1301 1302 CONFIG_TPM_AUTH_SESSIONS 1303 Define this to enable authorized functions in the TPM library. 1304 Requires CONFIG_TPM and CONFIG_SHA1. 1305 1306- USB Support: 1307 At the moment only the UHCI host controller is 1308 supported (PIP405, MIP405, MPC5200); define 1309 CONFIG_USB_UHCI to enable it. 1310 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1311 and define CONFIG_USB_STORAGE to enable the USB 1312 storage devices. 1313 Note: 1314 Supported are USB Keyboards and USB Floppy drives 1315 (TEAC FD-05PUB). 1316 MPC5200 USB requires additional defines: 1317 CONFIG_USB_CLOCK 1318 for 528 MHz Clock: 0x0001bbbb 1319 CONFIG_PSC3_USB 1320 for USB on PSC3 1321 CONFIG_USB_CONFIG 1322 for differential drivers: 0x00001000 1323 for single ended drivers: 0x00005000 1324 for differential drivers on PSC3: 0x00000100 1325 for single ended drivers on PSC3: 0x00004100 1326 CONFIG_SYS_USB_EVENT_POLL 1327 May be defined to allow interrupt polling 1328 instead of using asynchronous interrupts 1329 1330 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the 1331 txfilltuning field in the EHCI controller on reset. 1332 1333 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2 1334 HW module registers. 1335 1336- USB Device: 1337 Define the below if you wish to use the USB console. 1338 Once firmware is rebuilt from a serial console issue the 1339 command "setenv stdin usbtty; setenv stdout usbtty" and 1340 attach your USB cable. The Unix command "dmesg" should print 1341 it has found a new device. The environment variable usbtty 1342 can be set to gserial or cdc_acm to enable your device to 1343 appear to a USB host as a Linux gserial device or a 1344 Common Device Class Abstract Control Model serial device. 1345 If you select usbtty = gserial you should be able to enumerate 1346 a Linux host by 1347 # modprobe usbserial vendor=0xVendorID product=0xProductID 1348 else if using cdc_acm, simply setting the environment 1349 variable usbtty to be cdc_acm should suffice. The following 1350 might be defined in YourBoardName.h 1351 1352 CONFIG_USB_DEVICE 1353 Define this to build a UDC device 1354 1355 CONFIG_USB_TTY 1356 Define this to have a tty type of device available to 1357 talk to the UDC device 1358 1359 CONFIG_USBD_HS 1360 Define this to enable the high speed support for usb 1361 device and usbtty. If this feature is enabled, a routine 1362 int is_usbd_high_speed(void) 1363 also needs to be defined by the driver to dynamically poll 1364 whether the enumeration has succeded at high speed or full 1365 speed. 1366 1367 CONFIG_SYS_CONSOLE_IS_IN_ENV 1368 Define this if you want stdin, stdout &/or stderr to 1369 be set to usbtty. 1370 1371 mpc8xx: 1372 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1373 Derive USB clock from external clock "blah" 1374 - CONFIG_SYS_USB_EXTC_CLK 0x02 1375 1376 If you have a USB-IF assigned VendorID then you may wish to 1377 define your own vendor specific values either in BoardName.h 1378 or directly in usbd_vendor_info.h. If you don't define 1379 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1380 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1381 should pretend to be a Linux device to it's target host. 1382 1383 CONFIG_USBD_MANUFACTURER 1384 Define this string as the name of your company for 1385 - CONFIG_USBD_MANUFACTURER "my company" 1386 1387 CONFIG_USBD_PRODUCT_NAME 1388 Define this string as the name of your product 1389 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1390 1391 CONFIG_USBD_VENDORID 1392 Define this as your assigned Vendor ID from the USB 1393 Implementors Forum. This *must* be a genuine Vendor ID 1394 to avoid polluting the USB namespace. 1395 - CONFIG_USBD_VENDORID 0xFFFF 1396 1397 CONFIG_USBD_PRODUCTID 1398 Define this as the unique Product ID 1399 for your device 1400 - CONFIG_USBD_PRODUCTID 0xFFFF 1401 1402- ULPI Layer Support: 1403 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via 1404 the generic ULPI layer. The generic layer accesses the ULPI PHY 1405 via the platform viewport, so you need both the genric layer and 1406 the viewport enabled. Currently only Chipidea/ARC based 1407 viewport is supported. 1408 To enable the ULPI layer support, define CONFIG_USB_ULPI and 1409 CONFIG_USB_ULPI_VIEWPORT in your board configuration file. 1410 If your ULPI phy needs a different reference clock than the 1411 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to 1412 the appropriate value in Hz. 1413 1414- MMC Support: 1415 The MMC controller on the Intel PXA is supported. To 1416 enable this define CONFIG_MMC. The MMC can be 1417 accessed from the boot prompt by mapping the device 1418 to physical memory similar to flash. Command line is 1419 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1420 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1421 1422 CONFIG_SH_MMCIF 1423 Support for Renesas on-chip MMCIF controller 1424 1425 CONFIG_SH_MMCIF_ADDR 1426 Define the base address of MMCIF registers 1427 1428 CONFIG_SH_MMCIF_CLK 1429 Define the clock frequency for MMCIF 1430 1431 CONFIG_SUPPORT_EMMC_BOOT 1432 Enable some additional features of the eMMC boot partitions. 1433 1434 CONFIG_SUPPORT_EMMC_RPMB 1435 Enable the commands for reading, writing and programming the 1436 key for the Replay Protection Memory Block partition in eMMC. 1437 1438- USB Device Firmware Update (DFU) class support: 1439 CONFIG_USB_FUNCTION_DFU 1440 This enables the USB portion of the DFU USB class 1441 1442 CONFIG_CMD_DFU 1443 This enables the command "dfu" which is used to have 1444 U-Boot create a DFU class device via USB. This command 1445 requires that the "dfu_alt_info" environment variable be 1446 set and define the alt settings to expose to the host. 1447 1448 CONFIG_DFU_MMC 1449 This enables support for exposing (e)MMC devices via DFU. 1450 1451 CONFIG_DFU_NAND 1452 This enables support for exposing NAND devices via DFU. 1453 1454 CONFIG_DFU_RAM 1455 This enables support for exposing RAM via DFU. 1456 Note: DFU spec refer to non-volatile memory usage, but 1457 allow usages beyond the scope of spec - here RAM usage, 1458 one that would help mostly the developer. 1459 1460 CONFIG_SYS_DFU_DATA_BUF_SIZE 1461 Dfu transfer uses a buffer before writing data to the 1462 raw storage device. Make the size (in bytes) of this buffer 1463 configurable. The size of this buffer is also configurable 1464 through the "dfu_bufsiz" environment variable. 1465 1466 CONFIG_SYS_DFU_MAX_FILE_SIZE 1467 When updating files rather than the raw storage device, 1468 we use a static buffer to copy the file into and then write 1469 the buffer once we've been given the whole file. Define 1470 this to the maximum filesize (in bytes) for the buffer. 1471 Default is 4 MiB if undefined. 1472 1473 DFU_DEFAULT_POLL_TIMEOUT 1474 Poll timeout [ms], is the timeout a device can send to the 1475 host. The host must wait for this timeout before sending 1476 a subsequent DFU_GET_STATUS request to the device. 1477 1478 DFU_MANIFEST_POLL_TIMEOUT 1479 Poll timeout [ms], which the device sends to the host when 1480 entering dfuMANIFEST state. Host waits this timeout, before 1481 sending again an USB request to the device. 1482 1483- USB Device Android Fastboot support: 1484 CONFIG_USB_FUNCTION_FASTBOOT 1485 This enables the USB part of the fastboot gadget 1486 1487 CONFIG_CMD_FASTBOOT 1488 This enables the command "fastboot" which enables the Android 1489 fastboot mode for the platform's USB device. Fastboot is a USB 1490 protocol for downloading images, flashing and device control 1491 used on Android devices. 1492 See doc/README.android-fastboot for more information. 1493 1494 CONFIG_ANDROID_BOOT_IMAGE 1495 This enables support for booting images which use the Android 1496 image format header. 1497 1498 CONFIG_FASTBOOT_BUF_ADDR 1499 The fastboot protocol requires a large memory buffer for 1500 downloads. Define this to the starting RAM address to use for 1501 downloaded images. 1502 1503 CONFIG_FASTBOOT_BUF_SIZE 1504 The fastboot protocol requires a large memory buffer for 1505 downloads. This buffer should be as large as possible for a 1506 platform. Define this to the size available RAM for fastboot. 1507 1508 CONFIG_FASTBOOT_FLASH 1509 The fastboot protocol includes a "flash" command for writing 1510 the downloaded image to a non-volatile storage device. Define 1511 this to enable the "fastboot flash" command. 1512 1513 CONFIG_FASTBOOT_FLASH_MMC_DEV 1514 The fastboot "flash" command requires additional information 1515 regarding the non-volatile storage device. Define this to 1516 the eMMC device that fastboot should use to store the image. 1517 1518 CONFIG_FASTBOOT_GPT_NAME 1519 The fastboot "flash" command supports writing the downloaded 1520 image to the Protective MBR and the Primary GUID Partition 1521 Table. (Additionally, this downloaded image is post-processed 1522 to generate and write the Backup GUID Partition Table.) 1523 This occurs when the specified "partition name" on the 1524 "fastboot flash" command line matches this value. 1525 The default is "gpt" if undefined. 1526 1527 CONFIG_FASTBOOT_MBR_NAME 1528 The fastboot "flash" command supports writing the downloaded 1529 image to DOS MBR. 1530 This occurs when the "partition name" specified on the 1531 "fastboot flash" command line matches this value. 1532 If not defined the default value "mbr" is used. 1533 1534- Journaling Flash filesystem support: 1535 CONFIG_JFFS2_NAND 1536 Define these for a default partition on a NAND device 1537 1538 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1539 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1540 Define these for a default partition on a NOR device 1541 1542- FAT(File Allocation Table) filesystem write function support: 1543 CONFIG_FAT_WRITE 1544 1545 Define this to enable support for saving memory data as a 1546 file in FAT formatted partition. 1547 1548 This will also enable the command "fatwrite" enabling the 1549 user to write files to FAT. 1550 1551- FAT(File Allocation Table) filesystem cluster size: 1552 CONFIG_FS_FAT_MAX_CLUSTSIZE 1553 1554 Define the max cluster size for fat operations else 1555 a default value of 65536 will be defined. 1556 1557- Keyboard Support: 1558 See Kconfig help for available keyboard drivers. 1559 1560 CONFIG_KEYBOARD 1561 1562 Define this to enable a custom keyboard support. 1563 This simply calls drv_keyboard_init() which must be 1564 defined in your board-specific files. This option is deprecated 1565 and is only used by novena. For new boards, use driver model 1566 instead. 1567 1568- Video support: 1569 CONFIG_FSL_DIU_FB 1570 Enable the Freescale DIU video driver. Reference boards for 1571 SOCs that have a DIU should define this macro to enable DIU 1572 support, and should also define these other macros: 1573 1574 CONFIG_SYS_DIU_ADDR 1575 CONFIG_VIDEO 1576 CONFIG_CFB_CONSOLE 1577 CONFIG_VIDEO_SW_CURSOR 1578 CONFIG_VGA_AS_SINGLE_DEVICE 1579 CONFIG_VIDEO_LOGO 1580 CONFIG_VIDEO_BMP_LOGO 1581 1582 The DIU driver will look for the 'video-mode' environment 1583 variable, and if defined, enable the DIU as a console during 1584 boot. See the documentation file doc/README.video for a 1585 description of this variable. 1586 1587- LCD Support: CONFIG_LCD 1588 1589 Define this to enable LCD support (for output to LCD 1590 display); also select one of the supported displays 1591 by defining one of these: 1592 1593 CONFIG_ATMEL_LCD: 1594 1595 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1596 1597 CONFIG_NEC_NL6448AC33: 1598 1599 NEC NL6448AC33-18. Active, color, single scan. 1600 1601 CONFIG_NEC_NL6448BC20 1602 1603 NEC NL6448BC20-08. 6.5", 640x480. 1604 Active, color, single scan. 1605 1606 CONFIG_NEC_NL6448BC33_54 1607 1608 NEC NL6448BC33-54. 10.4", 640x480. 1609 Active, color, single scan. 1610 1611 CONFIG_SHARP_16x9 1612 1613 Sharp 320x240. Active, color, single scan. 1614 It isn't 16x9, and I am not sure what it is. 1615 1616 CONFIG_SHARP_LQ64D341 1617 1618 Sharp LQ64D341 display, 640x480. 1619 Active, color, single scan. 1620 1621 CONFIG_HLD1045 1622 1623 HLD1045 display, 640x480. 1624 Active, color, single scan. 1625 1626 CONFIG_OPTREX_BW 1627 1628 Optrex CBL50840-2 NF-FW 99 22 M5 1629 or 1630 Hitachi LMG6912RPFC-00T 1631 or 1632 Hitachi SP14Q002 1633 1634 320x240. Black & white. 1635 1636 CONFIG_LCD_ALIGNMENT 1637 1638 Normally the LCD is page-aligned (typically 4KB). If this is 1639 defined then the LCD will be aligned to this value instead. 1640 For ARM it is sometimes useful to use MMU_SECTION_SIZE 1641 here, since it is cheaper to change data cache settings on 1642 a per-section basis. 1643 1644 1645 CONFIG_LCD_ROTATION 1646 1647 Sometimes, for example if the display is mounted in portrait 1648 mode or even if it's mounted landscape but rotated by 180degree, 1649 we need to rotate our content of the display relative to the 1650 framebuffer, so that user can read the messages which are 1651 printed out. 1652 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be 1653 initialized with a given rotation from "vl_rot" out of 1654 "vidinfo_t" which is provided by the board specific code. 1655 The value for vl_rot is coded as following (matching to 1656 fbcon=rotate:<n> linux-kernel commandline): 1657 0 = no rotation respectively 0 degree 1658 1 = 90 degree rotation 1659 2 = 180 degree rotation 1660 3 = 270 degree rotation 1661 1662 If CONFIG_LCD_ROTATION is not defined, the console will be 1663 initialized with 0degree rotation. 1664 1665 CONFIG_LCD_BMP_RLE8 1666 1667 Support drawing of RLE8-compressed bitmaps on the LCD. 1668 1669 CONFIG_I2C_EDID 1670 1671 Enables an 'i2c edid' command which can read EDID 1672 information over I2C from an attached LCD display. 1673 1674- Splash Screen Support: CONFIG_SPLASH_SCREEN 1675 1676 If this option is set, the environment is checked for 1677 a variable "splashimage". If found, the usual display 1678 of logo, copyright and system information on the LCD 1679 is suppressed and the BMP image at the address 1680 specified in "splashimage" is loaded instead. The 1681 console is redirected to the "nulldev", too. This 1682 allows for a "silent" boot where a splash screen is 1683 loaded very quickly after power-on. 1684 1685 CONFIG_SPLASHIMAGE_GUARD 1686 1687 If this option is set, then U-Boot will prevent the environment 1688 variable "splashimage" from being set to a problematic address 1689 (see doc/README.displaying-bmps). 1690 This option is useful for targets where, due to alignment 1691 restrictions, an improperly aligned BMP image will cause a data 1692 abort. If you think you will not have problems with unaligned 1693 accesses (for example because your toolchain prevents them) 1694 there is no need to set this option. 1695 1696 CONFIG_SPLASH_SCREEN_ALIGN 1697 1698 If this option is set the splash image can be freely positioned 1699 on the screen. Environment variable "splashpos" specifies the 1700 position as "x,y". If a positive number is given it is used as 1701 number of pixel from left/top. If a negative number is given it 1702 is used as number of pixel from right/bottom. You can also 1703 specify 'm' for centering the image. 1704 1705 Example: 1706 setenv splashpos m,m 1707 => image at center of screen 1708 1709 setenv splashpos 30,20 1710 => image at x = 30 and y = 20 1711 1712 setenv splashpos -10,m 1713 => vertically centered image 1714 at x = dspWidth - bmpWidth - 9 1715 1716- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1717 1718 If this option is set, additionally to standard BMP 1719 images, gzipped BMP images can be displayed via the 1720 splashscreen support or the bmp command. 1721 1722- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 1723 1724 If this option is set, 8-bit RLE compressed BMP images 1725 can be displayed via the splashscreen support or the 1726 bmp command. 1727 1728- Compression support: 1729 CONFIG_GZIP 1730 1731 Enabled by default to support gzip compressed images. 1732 1733 CONFIG_BZIP2 1734 1735 If this option is set, support for bzip2 compressed 1736 images is included. If not, only uncompressed and gzip 1737 compressed images are supported. 1738 1739 NOTE: the bzip2 algorithm requires a lot of RAM, so 1740 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 1741 be at least 4MB. 1742 1743 CONFIG_LZMA 1744 1745 If this option is set, support for lzma compressed 1746 images is included. 1747 1748 Note: The LZMA algorithm adds between 2 and 4KB of code and it 1749 requires an amount of dynamic memory that is given by the 1750 formula: 1751 1752 (1846 + 768 << (lc + lp)) * sizeof(uint16) 1753 1754 Where lc and lp stand for, respectively, Literal context bits 1755 and Literal pos bits. 1756 1757 This value is upper-bounded by 14MB in the worst case. Anyway, 1758 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 1759 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 1760 a very small buffer. 1761 1762 Use the lzmainfo tool to determinate the lc and lp values and 1763 then calculate the amount of needed dynamic memory (ensuring 1764 the appropriate CONFIG_SYS_MALLOC_LEN value). 1765 1766 CONFIG_LZO 1767 1768 If this option is set, support for LZO compressed images 1769 is included. 1770 1771- MII/PHY support: 1772 CONFIG_PHY_ADDR 1773 1774 The address of PHY on MII bus. 1775 1776 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1777 1778 The clock frequency of the MII bus 1779 1780 CONFIG_PHY_GIGE 1781 1782 If this option is set, support for speed/duplex 1783 detection of gigabit PHY is included. 1784 1785 CONFIG_PHY_RESET_DELAY 1786 1787 Some PHY like Intel LXT971A need extra delay after 1788 reset before any MII register access is possible. 1789 For such PHY, set this option to the usec delay 1790 required. (minimum 300usec for LXT971A) 1791 1792 CONFIG_PHY_CMD_DELAY (ppc4xx) 1793 1794 Some PHY like Intel LXT971A need extra delay after 1795 command issued before MII status register can be read 1796 1797- IP address: 1798 CONFIG_IPADDR 1799 1800 Define a default value for the IP address to use for 1801 the default Ethernet interface, in case this is not 1802 determined through e.g. bootp. 1803 (Environment variable "ipaddr") 1804 1805- Server IP address: 1806 CONFIG_SERVERIP 1807 1808 Defines a default value for the IP address of a TFTP 1809 server to contact when using the "tftboot" command. 1810 (Environment variable "serverip") 1811 1812 CONFIG_KEEP_SERVERADDR 1813 1814 Keeps the server's MAC address, in the env 'serveraddr' 1815 for passing to bootargs (like Linux's netconsole option) 1816 1817- Gateway IP address: 1818 CONFIG_GATEWAYIP 1819 1820 Defines a default value for the IP address of the 1821 default router where packets to other networks are 1822 sent to. 1823 (Environment variable "gatewayip") 1824 1825- Subnet mask: 1826 CONFIG_NETMASK 1827 1828 Defines a default value for the subnet mask (or 1829 routing prefix) which is used to determine if an IP 1830 address belongs to the local subnet or needs to be 1831 forwarded through a router. 1832 (Environment variable "netmask") 1833 1834- Multicast TFTP Mode: 1835 CONFIG_MCAST_TFTP 1836 1837 Defines whether you want to support multicast TFTP as per 1838 rfc-2090; for example to work with atftp. Lets lots of targets 1839 tftp down the same boot image concurrently. Note: the Ethernet 1840 driver in use must provide a function: mcast() to join/leave a 1841 multicast group. 1842 1843- BOOTP Recovery Mode: 1844 CONFIG_BOOTP_RANDOM_DELAY 1845 1846 If you have many targets in a network that try to 1847 boot using BOOTP, you may want to avoid that all 1848 systems send out BOOTP requests at precisely the same 1849 moment (which would happen for instance at recovery 1850 from a power failure, when all systems will try to 1851 boot, thus flooding the BOOTP server. Defining 1852 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1853 inserted before sending out BOOTP requests. The 1854 following delays are inserted then: 1855 1856 1st BOOTP request: delay 0 ... 1 sec 1857 2nd BOOTP request: delay 0 ... 2 sec 1858 3rd BOOTP request: delay 0 ... 4 sec 1859 4th and following 1860 BOOTP requests: delay 0 ... 8 sec 1861 1862 CONFIG_BOOTP_ID_CACHE_SIZE 1863 1864 BOOTP packets are uniquely identified using a 32-bit ID. The 1865 server will copy the ID from client requests to responses and 1866 U-Boot will use this to determine if it is the destination of 1867 an incoming response. Some servers will check that addresses 1868 aren't in use before handing them out (usually using an ARP 1869 ping) and therefore take up to a few hundred milliseconds to 1870 respond. Network congestion may also influence the time it 1871 takes for a response to make it back to the client. If that 1872 time is too long, U-Boot will retransmit requests. In order 1873 to allow earlier responses to still be accepted after these 1874 retransmissions, U-Boot's BOOTP client keeps a small cache of 1875 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this 1876 cache. The default is to keep IDs for up to four outstanding 1877 requests. Increasing this will allow U-Boot to accept offers 1878 from a BOOTP client in networks with unusually high latency. 1879 1880- DHCP Advanced Options: 1881 You can fine tune the DHCP functionality by defining 1882 CONFIG_BOOTP_* symbols: 1883 1884 CONFIG_BOOTP_SUBNETMASK 1885 CONFIG_BOOTP_GATEWAY 1886 CONFIG_BOOTP_HOSTNAME 1887 CONFIG_BOOTP_NISDOMAIN 1888 CONFIG_BOOTP_BOOTPATH 1889 CONFIG_BOOTP_BOOTFILESIZE 1890 CONFIG_BOOTP_DNS 1891 CONFIG_BOOTP_DNS2 1892 CONFIG_BOOTP_SEND_HOSTNAME 1893 CONFIG_BOOTP_NTPSERVER 1894 CONFIG_BOOTP_TIMEOFFSET 1895 CONFIG_BOOTP_VENDOREX 1896 CONFIG_BOOTP_MAY_FAIL 1897 1898 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 1899 environment variable, not the BOOTP server. 1900 1901 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found 1902 after the configured retry count, the call will fail 1903 instead of starting over. This can be used to fail over 1904 to Link-local IP address configuration if the DHCP server 1905 is not available. 1906 1907 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 1908 serverip from a DHCP server, it is possible that more 1909 than one DNS serverip is offered to the client. 1910 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 1911 serverip will be stored in the additional environment 1912 variable "dnsip2". The first DNS serverip is always 1913 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 1914 is defined. 1915 1916 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 1917 to do a dynamic update of a DNS server. To do this, they 1918 need the hostname of the DHCP requester. 1919 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 1920 of the "hostname" environment variable is passed as 1921 option 12 to the DHCP server. 1922 1923 CONFIG_BOOTP_DHCP_REQUEST_DELAY 1924 1925 A 32bit value in microseconds for a delay between 1926 receiving a "DHCP Offer" and sending the "DHCP Request". 1927 This fixes a problem with certain DHCP servers that don't 1928 respond 100% of the time to a "DHCP request". E.g. On an 1929 AT91RM9200 processor running at 180MHz, this delay needed 1930 to be *at least* 15,000 usec before a Windows Server 2003 1931 DHCP server would reply 100% of the time. I recommend at 1932 least 50,000 usec to be safe. The alternative is to hope 1933 that one of the retries will be successful but note that 1934 the DHCP timeout and retry process takes a longer than 1935 this delay. 1936 1937 - Link-local IP address negotiation: 1938 Negotiate with other link-local clients on the local network 1939 for an address that doesn't require explicit configuration. 1940 This is especially useful if a DHCP server cannot be guaranteed 1941 to exist in all environments that the device must operate. 1942 1943 See doc/README.link-local for more information. 1944 1945 - CDP Options: 1946 CONFIG_CDP_DEVICE_ID 1947 1948 The device id used in CDP trigger frames. 1949 1950 CONFIG_CDP_DEVICE_ID_PREFIX 1951 1952 A two character string which is prefixed to the MAC address 1953 of the device. 1954 1955 CONFIG_CDP_PORT_ID 1956 1957 A printf format string which contains the ascii name of 1958 the port. Normally is set to "eth%d" which sets 1959 eth0 for the first Ethernet, eth1 for the second etc. 1960 1961 CONFIG_CDP_CAPABILITIES 1962 1963 A 32bit integer which indicates the device capabilities; 1964 0x00000010 for a normal host which does not forwards. 1965 1966 CONFIG_CDP_VERSION 1967 1968 An ascii string containing the version of the software. 1969 1970 CONFIG_CDP_PLATFORM 1971 1972 An ascii string containing the name of the platform. 1973 1974 CONFIG_CDP_TRIGGER 1975 1976 A 32bit integer sent on the trigger. 1977 1978 CONFIG_CDP_POWER_CONSUMPTION 1979 1980 A 16bit integer containing the power consumption of the 1981 device in .1 of milliwatts. 1982 1983 CONFIG_CDP_APPLIANCE_VLAN_TYPE 1984 1985 A byte containing the id of the VLAN. 1986 1987- Status LED: CONFIG_LED_STATUS 1988 1989 Several configurations allow to display the current 1990 status using a LED. For instance, the LED will blink 1991 fast while running U-Boot code, stop blinking as 1992 soon as a reply to a BOOTP request was received, and 1993 start blinking slow once the Linux kernel is running 1994 (supported by a status LED driver in the Linux 1995 kernel). Defining CONFIG_LED_STATUS enables this 1996 feature in U-Boot. 1997 1998 Additional options: 1999 2000 CONFIG_LED_STATUS_GPIO 2001 The status LED can be connected to a GPIO pin. 2002 In such cases, the gpio_led driver can be used as a 2003 status LED backend implementation. Define CONFIG_LED_STATUS_GPIO 2004 to include the gpio_led driver in the U-Boot binary. 2005 2006 CONFIG_GPIO_LED_INVERTED_TABLE 2007 Some GPIO connected LEDs may have inverted polarity in which 2008 case the GPIO high value corresponds to LED off state and 2009 GPIO low value corresponds to LED on state. 2010 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined 2011 with a list of GPIO LEDs that have inverted polarity. 2012 2013- CAN Support: CONFIG_CAN_DRIVER 2014 2015 Defining CONFIG_CAN_DRIVER enables CAN driver support 2016 on those systems that support this (optional) 2017 feature, like the TQM8xxL modules. 2018 2019- I2C Support: CONFIG_SYS_I2C 2020 2021 This enable the NEW i2c subsystem, and will allow you to use 2022 i2c commands at the u-boot command line (as long as you set 2023 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c 2024 based realtime clock chips or other i2c devices. See 2025 common/cmd_i2c.c for a description of the command line 2026 interface. 2027 2028 ported i2c driver to the new framework: 2029 - drivers/i2c/soft_i2c.c: 2030 - activate first bus with CONFIG_SYS_I2C_SOFT define 2031 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE 2032 for defining speed and slave address 2033 - activate second bus with I2C_SOFT_DECLARATIONS2 define 2034 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2 2035 for defining speed and slave address 2036 - activate third bus with I2C_SOFT_DECLARATIONS3 define 2037 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3 2038 for defining speed and slave address 2039 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define 2040 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4 2041 for defining speed and slave address 2042 2043 - drivers/i2c/fsl_i2c.c: 2044 - activate i2c driver with CONFIG_SYS_I2C_FSL 2045 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register 2046 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and 2047 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first 2048 bus. 2049 - If your board supports a second fsl i2c bus, define 2050 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset 2051 CONFIG_SYS_FSL_I2C2_SPEED for the speed and 2052 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the 2053 second bus. 2054 2055 - drivers/i2c/tegra_i2c.c: 2056 - activate this driver with CONFIG_SYS_I2C_TEGRA 2057 - This driver adds 4 i2c buses with a fix speed from 2058 100000 and the slave addr 0! 2059 2060 - drivers/i2c/ppc4xx_i2c.c 2061 - activate this driver with CONFIG_SYS_I2C_PPC4XX 2062 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0 2063 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1 2064 2065 - drivers/i2c/i2c_mxc.c 2066 - activate this driver with CONFIG_SYS_I2C_MXC 2067 - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1 2068 - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2 2069 - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3 2070 - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4 2071 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED 2072 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE 2073 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED 2074 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE 2075 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED 2076 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE 2077 - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED 2078 - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE 2079 If those defines are not set, default value is 100000 2080 for speed, and 0 for slave. 2081 2082 - drivers/i2c/rcar_i2c.c: 2083 - activate this driver with CONFIG_SYS_I2C_RCAR 2084 - This driver adds 4 i2c buses 2085 2086 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0 2087 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0 2088 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1 2089 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1 2090 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2 2091 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2 2092 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3 2093 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3 2094 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses 2095 2096 - drivers/i2c/sh_i2c.c: 2097 - activate this driver with CONFIG_SYS_I2C_SH 2098 - This driver adds from 2 to 5 i2c buses 2099 2100 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0 2101 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0 2102 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1 2103 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1 2104 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2 2105 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2 2106 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3 2107 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3 2108 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4 2109 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4 2110 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses 2111 2112 - drivers/i2c/omap24xx_i2c.c 2113 - activate this driver with CONFIG_SYS_I2C_OMAP24XX 2114 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0 2115 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0 2116 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1 2117 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1 2118 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2 2119 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2 2120 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3 2121 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3 2122 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4 2123 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4 2124 2125 - drivers/i2c/zynq_i2c.c 2126 - activate this driver with CONFIG_SYS_I2C_ZYNQ 2127 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting 2128 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr 2129 2130 - drivers/i2c/s3c24x0_i2c.c: 2131 - activate this driver with CONFIG_SYS_I2C_S3C24X0 2132 - This driver adds i2c buses (11 for Exynos5250, Exynos5420 2133 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung) 2134 with a fix speed from 100000 and the slave addr 0! 2135 2136 - drivers/i2c/ihs_i2c.c 2137 - activate this driver with CONFIG_SYS_I2C_IHS 2138 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0 2139 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0 2140 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0 2141 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1 2142 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1 2143 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1 2144 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2 2145 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2 2146 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2 2147 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3 2148 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3 2149 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3 2150 - activate dual channel with CONFIG_SYS_I2C_IHS_DUAL 2151 - CONFIG_SYS_I2C_IHS_SPEED_0_1 speed channel 0_1 2152 - CONFIG_SYS_I2C_IHS_SLAVE_0_1 slave addr channel 0_1 2153 - CONFIG_SYS_I2C_IHS_SPEED_1_1 speed channel 1_1 2154 - CONFIG_SYS_I2C_IHS_SLAVE_1_1 slave addr channel 1_1 2155 - CONFIG_SYS_I2C_IHS_SPEED_2_1 speed channel 2_1 2156 - CONFIG_SYS_I2C_IHS_SLAVE_2_1 slave addr channel 2_1 2157 - CONFIG_SYS_I2C_IHS_SPEED_3_1 speed channel 3_1 2158 - CONFIG_SYS_I2C_IHS_SLAVE_3_1 slave addr channel 3_1 2159 2160 additional defines: 2161 2162 CONFIG_SYS_NUM_I2C_BUSES 2163 Hold the number of i2c buses you want to use. 2164 2165 CONFIG_SYS_I2C_DIRECT_BUS 2166 define this, if you don't use i2c muxes on your hardware. 2167 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can 2168 omit this define. 2169 2170 CONFIG_SYS_I2C_MAX_HOPS 2171 define how many muxes are maximal consecutively connected 2172 on one i2c bus. If you not use i2c muxes, omit this 2173 define. 2174 2175 CONFIG_SYS_I2C_BUSES 2176 hold a list of buses you want to use, only used if 2177 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example 2178 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and 2179 CONFIG_SYS_NUM_I2C_BUSES = 9: 2180 2181 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \ 2182 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \ 2183 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \ 2184 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \ 2185 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \ 2186 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \ 2187 {1, {I2C_NULL_HOP}}, \ 2188 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \ 2189 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \ 2190 } 2191 2192 which defines 2193 bus 0 on adapter 0 without a mux 2194 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1 2195 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2 2196 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3 2197 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4 2198 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5 2199 bus 6 on adapter 1 without a mux 2200 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1 2201 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2 2202 2203 If you do not have i2c muxes on your board, omit this define. 2204 2205- Legacy I2C Support: 2206 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT) 2207 then the following macros need to be defined (examples are 2208 from include/configs/lwmon.h): 2209 2210 I2C_INIT 2211 2212 (Optional). Any commands necessary to enable the I2C 2213 controller or configure ports. 2214 2215 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 2216 2217 I2C_PORT 2218 2219 (Only for MPC8260 CPU). The I/O port to use (the code 2220 assumes both bits are on the same port). Valid values 2221 are 0..3 for ports A..D. 2222 2223 I2C_ACTIVE 2224 2225 The code necessary to make the I2C data line active 2226 (driven). If the data line is open collector, this 2227 define can be null. 2228 2229 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 2230 2231 I2C_TRISTATE 2232 2233 The code necessary to make the I2C data line tri-stated 2234 (inactive). If the data line is open collector, this 2235 define can be null. 2236 2237 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 2238 2239 I2C_READ 2240 2241 Code that returns true if the I2C data line is high, 2242 false if it is low. 2243 2244 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 2245 2246 I2C_SDA(bit) 2247 2248 If <bit> is true, sets the I2C data line high. If it 2249 is false, it clears it (low). 2250 2251 eg: #define I2C_SDA(bit) \ 2252 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 2253 else immr->im_cpm.cp_pbdat &= ~PB_SDA 2254 2255 I2C_SCL(bit) 2256 2257 If <bit> is true, sets the I2C clock line high. If it 2258 is false, it clears it (low). 2259 2260 eg: #define I2C_SCL(bit) \ 2261 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 2262 else immr->im_cpm.cp_pbdat &= ~PB_SCL 2263 2264 I2C_DELAY 2265 2266 This delay is invoked four times per clock cycle so this 2267 controls the rate of data transfer. The data rate thus 2268 is 1 / (I2C_DELAY * 4). Often defined to be something 2269 like: 2270 2271 #define I2C_DELAY udelay(2) 2272 2273 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 2274 2275 If your arch supports the generic GPIO framework (asm/gpio.h), 2276 then you may alternatively define the two GPIOs that are to be 2277 used as SCL / SDA. Any of the previous I2C_xxx macros will 2278 have GPIO-based defaults assigned to them as appropriate. 2279 2280 You should define these to the GPIO value as given directly to 2281 the generic GPIO functions. 2282 2283 CONFIG_SYS_I2C_INIT_BOARD 2284 2285 When a board is reset during an i2c bus transfer 2286 chips might think that the current transfer is still 2287 in progress. On some boards it is possible to access 2288 the i2c SCLK line directly, either by using the 2289 processor pin as a GPIO or by having a second pin 2290 connected to the bus. If this option is defined a 2291 custom i2c_init_board() routine in boards/xxx/board.c 2292 is run early in the boot sequence. 2293 2294 CONFIG_I2C_MULTI_BUS 2295 2296 This option allows the use of multiple I2C buses, each of which 2297 must have a controller. At any point in time, only one bus is 2298 active. To switch to a different bus, use the 'i2c dev' command. 2299 Note that bus numbering is zero-based. 2300 2301 CONFIG_SYS_I2C_NOPROBES 2302 2303 This option specifies a list of I2C devices that will be skipped 2304 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 2305 is set, specify a list of bus-device pairs. Otherwise, specify 2306 a 1D array of device addresses 2307 2308 e.g. 2309 #undef CONFIG_I2C_MULTI_BUS 2310 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 2311 2312 will skip addresses 0x50 and 0x68 on a board with one I2C bus 2313 2314 #define CONFIG_I2C_MULTI_BUS 2315 #define CONFIG_SYS_I2C_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 2316 2317 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 2318 2319 CONFIG_SYS_SPD_BUS_NUM 2320 2321 If defined, then this indicates the I2C bus number for DDR SPD. 2322 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 2323 2324 CONFIG_SYS_RTC_BUS_NUM 2325 2326 If defined, then this indicates the I2C bus number for the RTC. 2327 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 2328 2329 CONFIG_SYS_DTT_BUS_NUM 2330 2331 If defined, then this indicates the I2C bus number for the DTT. 2332 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 2333 2334 CONFIG_SYS_I2C_DTT_ADDR: 2335 2336 If defined, specifies the I2C address of the DTT device. 2337 If not defined, then U-Boot uses predefined value for 2338 specified DTT device. 2339 2340 CONFIG_SOFT_I2C_READ_REPEATED_START 2341 2342 defining this will force the i2c_read() function in 2343 the soft_i2c driver to perform an I2C repeated start 2344 between writing the address pointer and reading the 2345 data. If this define is omitted the default behaviour 2346 of doing a stop-start sequence will be used. Most I2C 2347 devices can use either method, but some require one or 2348 the other. 2349 2350- SPI Support: CONFIG_SPI 2351 2352 Enables SPI driver (so far only tested with 2353 SPI EEPROM, also an instance works with Crystal A/D and 2354 D/As on the SACSng board) 2355 2356 CONFIG_SH_SPI 2357 2358 Enables the driver for SPI controller on SuperH. Currently 2359 only SH7757 is supported. 2360 2361 CONFIG_SOFT_SPI 2362 2363 Enables a software (bit-bang) SPI driver rather than 2364 using hardware support. This is a general purpose 2365 driver that only requires three general I/O port pins 2366 (two outputs, one input) to function. If this is 2367 defined, the board configuration must define several 2368 SPI configuration items (port pins to use, etc). For 2369 an example, see include/configs/sacsng.h. 2370 2371 CONFIG_HARD_SPI 2372 2373 Enables a hardware SPI driver for general-purpose reads 2374 and writes. As with CONFIG_SOFT_SPI, the board configuration 2375 must define a list of chip-select function pointers. 2376 Currently supported on some MPC8xxx processors. For an 2377 example, see include/configs/mpc8349emds.h. 2378 2379 CONFIG_MXC_SPI 2380 2381 Enables the driver for the SPI controllers on i.MX and MXC 2382 SoCs. Currently i.MX31/35/51 are supported. 2383 2384 CONFIG_SYS_SPI_MXC_WAIT 2385 Timeout for waiting until spi transfer completed. 2386 default: (CONFIG_SYS_HZ/100) /* 10 ms */ 2387 2388- FPGA Support: CONFIG_FPGA 2389 2390 Enables FPGA subsystem. 2391 2392 CONFIG_FPGA_<vendor> 2393 2394 Enables support for specific chip vendors. 2395 (ALTERA, XILINX) 2396 2397 CONFIG_FPGA_<family> 2398 2399 Enables support for FPGA family. 2400 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 2401 2402 CONFIG_FPGA_COUNT 2403 2404 Specify the number of FPGA devices to support. 2405 2406 CONFIG_CMD_FPGA_LOADMK 2407 2408 Enable support for fpga loadmk command 2409 2410 CONFIG_CMD_FPGA_LOADP 2411 2412 Enable support for fpga loadp command - load partial bitstream 2413 2414 CONFIG_CMD_FPGA_LOADBP 2415 2416 Enable support for fpga loadbp command - load partial bitstream 2417 (Xilinx only) 2418 2419 CONFIG_SYS_FPGA_PROG_FEEDBACK 2420 2421 Enable printing of hash marks during FPGA configuration. 2422 2423 CONFIG_SYS_FPGA_CHECK_BUSY 2424 2425 Enable checks on FPGA configuration interface busy 2426 status by the configuration function. This option 2427 will require a board or device specific function to 2428 be written. 2429 2430 CONFIG_FPGA_DELAY 2431 2432 If defined, a function that provides delays in the FPGA 2433 configuration driver. 2434 2435 CONFIG_SYS_FPGA_CHECK_CTRLC 2436 Allow Control-C to interrupt FPGA configuration 2437 2438 CONFIG_SYS_FPGA_CHECK_ERROR 2439 2440 Check for configuration errors during FPGA bitfile 2441 loading. For example, abort during Virtex II 2442 configuration if the INIT_B line goes low (which 2443 indicated a CRC error). 2444 2445 CONFIG_SYS_FPGA_WAIT_INIT 2446 2447 Maximum time to wait for the INIT_B line to de-assert 2448 after PROB_B has been de-asserted during a Virtex II 2449 FPGA configuration sequence. The default time is 500 2450 ms. 2451 2452 CONFIG_SYS_FPGA_WAIT_BUSY 2453 2454 Maximum time to wait for BUSY to de-assert during 2455 Virtex II FPGA configuration. The default is 5 ms. 2456 2457 CONFIG_SYS_FPGA_WAIT_CONFIG 2458 2459 Time to wait after FPGA configuration. The default is 2460 200 ms. 2461 2462- Configuration Management: 2463 CONFIG_BUILD_TARGET 2464 2465 Some SoCs need special image types (e.g. U-Boot binary 2466 with a special header) as build targets. By defining 2467 CONFIG_BUILD_TARGET in the SoC / board header, this 2468 special image will be automatically built upon calling 2469 make / buildman. 2470 2471 CONFIG_IDENT_STRING 2472 2473 If defined, this string will be added to the U-Boot 2474 version information (U_BOOT_VERSION) 2475 2476- Vendor Parameter Protection: 2477 2478 U-Boot considers the values of the environment 2479 variables "serial#" (Board Serial Number) and 2480 "ethaddr" (Ethernet Address) to be parameters that 2481 are set once by the board vendor / manufacturer, and 2482 protects these variables from casual modification by 2483 the user. Once set, these variables are read-only, 2484 and write or delete attempts are rejected. You can 2485 change this behaviour: 2486 2487 If CONFIG_ENV_OVERWRITE is #defined in your config 2488 file, the write protection for vendor parameters is 2489 completely disabled. Anybody can change or delete 2490 these parameters. 2491 2492 Alternatively, if you define _both_ an ethaddr in the 2493 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2494 Ethernet address is installed in the environment, 2495 which can be changed exactly ONCE by the user. [The 2496 serial# is unaffected by this, i. e. it remains 2497 read-only.] 2498 2499 The same can be accomplished in a more flexible way 2500 for any variable by configuring the type of access 2501 to allow for those variables in the ".flags" variable 2502 or define CONFIG_ENV_FLAGS_LIST_STATIC. 2503 2504- Protected RAM: 2505 CONFIG_PRAM 2506 2507 Define this variable to enable the reservation of 2508 "protected RAM", i. e. RAM which is not overwritten 2509 by U-Boot. Define CONFIG_PRAM to hold the number of 2510 kB you want to reserve for pRAM. You can overwrite 2511 this default value by defining an environment 2512 variable "pram" to the number of kB you want to 2513 reserve. Note that the board info structure will 2514 still show the full amount of RAM. If pRAM is 2515 reserved, a new environment variable "mem" will 2516 automatically be defined to hold the amount of 2517 remaining RAM in a form that can be passed as boot 2518 argument to Linux, for instance like that: 2519 2520 setenv bootargs ... mem=\${mem} 2521 saveenv 2522 2523 This way you can tell Linux not to use this memory, 2524 either, which results in a memory region that will 2525 not be affected by reboots. 2526 2527 *WARNING* If your board configuration uses automatic 2528 detection of the RAM size, you must make sure that 2529 this memory test is non-destructive. So far, the 2530 following board configurations are known to be 2531 "pRAM-clean": 2532 2533 IVMS8, IVML24, SPD8xx, TQM8xxL, 2534 HERMES, IP860, RPXlite, LWMON, 2535 FLAGADM, TQM8260 2536 2537- Access to physical memory region (> 4GB) 2538 Some basic support is provided for operations on memory not 2539 normally accessible to U-Boot - e.g. some architectures 2540 support access to more than 4GB of memory on 32-bit 2541 machines using physical address extension or similar. 2542 Define CONFIG_PHYSMEM to access this basic support, which 2543 currently only supports clearing the memory. 2544 2545- Error Recovery: 2546 CONFIG_PANIC_HANG 2547 2548 Define this variable to stop the system in case of a 2549 fatal error, so that you have to reset it manually. 2550 This is probably NOT a good idea for an embedded 2551 system where you want the system to reboot 2552 automatically as fast as possible, but it may be 2553 useful during development since you can try to debug 2554 the conditions that lead to the situation. 2555 2556 CONFIG_NET_RETRY_COUNT 2557 2558 This variable defines the number of retries for 2559 network operations like ARP, RARP, TFTP, or BOOTP 2560 before giving up the operation. If not defined, a 2561 default value of 5 is used. 2562 2563 CONFIG_ARP_TIMEOUT 2564 2565 Timeout waiting for an ARP reply in milliseconds. 2566 2567 CONFIG_NFS_TIMEOUT 2568 2569 Timeout in milliseconds used in NFS protocol. 2570 If you encounter "ERROR: Cannot umount" in nfs command, 2571 try longer timeout such as 2572 #define CONFIG_NFS_TIMEOUT 10000UL 2573 2574- Command Interpreter: 2575 CONFIG_AUTO_COMPLETE 2576 2577 Enable auto completion of commands using TAB. 2578 2579 CONFIG_SYS_PROMPT_HUSH_PS2 2580 2581 This defines the secondary prompt string, which is 2582 printed when the command interpreter needs more input 2583 to complete a command. Usually "> ". 2584 2585 Note: 2586 2587 In the current implementation, the local variables 2588 space and global environment variables space are 2589 separated. Local variables are those you define by 2590 simply typing `name=value'. To access a local 2591 variable later on, you have write `$name' or 2592 `${name}'; to execute the contents of a variable 2593 directly type `$name' at the command prompt. 2594 2595 Global environment variables are those you use 2596 setenv/printenv to work with. To run a command stored 2597 in such a variable, you need to use the run command, 2598 and you must not use the '$' sign to access them. 2599 2600 To store commands and special characters in a 2601 variable, please use double quotation marks 2602 surrounding the whole text of the variable, instead 2603 of the backslashes before semicolons and special 2604 symbols. 2605 2606- Command Line Editing and History: 2607 CONFIG_CMDLINE_EDITING 2608 2609 Enable editing and History functions for interactive 2610 command line input operations 2611 2612- Command Line PS1/PS2 support: 2613 CONFIG_CMDLINE_PS_SUPPORT 2614 2615 Enable support for changing the command prompt string 2616 at run-time. Only static string is supported so far. 2617 The string is obtained from environment variables PS1 2618 and PS2. 2619 2620- Default Environment: 2621 CONFIG_EXTRA_ENV_SETTINGS 2622 2623 Define this to contain any number of null terminated 2624 strings (variable = value pairs) that will be part of 2625 the default environment compiled into the boot image. 2626 2627 For example, place something like this in your 2628 board's config file: 2629 2630 #define CONFIG_EXTRA_ENV_SETTINGS \ 2631 "myvar1=value1\0" \ 2632 "myvar2=value2\0" 2633 2634 Warning: This method is based on knowledge about the 2635 internal format how the environment is stored by the 2636 U-Boot code. This is NOT an official, exported 2637 interface! Although it is unlikely that this format 2638 will change soon, there is no guarantee either. 2639 You better know what you are doing here. 2640 2641 Note: overly (ab)use of the default environment is 2642 discouraged. Make sure to check other ways to preset 2643 the environment like the "source" command or the 2644 boot command first. 2645 2646 CONFIG_ENV_VARS_UBOOT_CONFIG 2647 2648 Define this in order to add variables describing the 2649 U-Boot build configuration to the default environment. 2650 These will be named arch, cpu, board, vendor, and soc. 2651 2652 Enabling this option will cause the following to be defined: 2653 2654 - CONFIG_SYS_ARCH 2655 - CONFIG_SYS_CPU 2656 - CONFIG_SYS_BOARD 2657 - CONFIG_SYS_VENDOR 2658 - CONFIG_SYS_SOC 2659 2660 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG 2661 2662 Define this in order to add variables describing certain 2663 run-time determined information about the hardware to the 2664 environment. These will be named board_name, board_rev. 2665 2666 CONFIG_DELAY_ENVIRONMENT 2667 2668 Normally the environment is loaded when the board is 2669 initialised so that it is available to U-Boot. This inhibits 2670 that so that the environment is not available until 2671 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL 2672 this is instead controlled by the value of 2673 /config/load-environment. 2674 2675- DataFlash Support: 2676 CONFIG_HAS_DATAFLASH 2677 2678 Defining this option enables DataFlash features and 2679 allows to read/write in Dataflash via the standard 2680 commands cp, md... 2681 2682- Serial Flash support 2683 CONFIG_CMD_SF 2684 2685 Defining this option enables SPI flash commands 2686 'sf probe/read/write/erase/update'. 2687 2688 Usage requires an initial 'probe' to define the serial 2689 flash parameters, followed by read/write/erase/update 2690 commands. 2691 2692 The following defaults may be provided by the platform 2693 to handle the common case when only a single serial 2694 flash is present on the system. 2695 2696 CONFIG_SF_DEFAULT_BUS Bus identifier 2697 CONFIG_SF_DEFAULT_CS Chip-select 2698 CONFIG_SF_DEFAULT_MODE (see include/spi.h) 2699 CONFIG_SF_DEFAULT_SPEED in Hz 2700 2701 CONFIG_CMD_SF_TEST 2702 2703 Define this option to include a destructive SPI flash 2704 test ('sf test'). 2705 2706 CONFIG_SF_DUAL_FLASH Dual flash memories 2707 2708 Define this option to use dual flash support where two flash 2709 memories can be connected with a given cs line. 2710 Currently Xilinx Zynq qspi supports these type of connections. 2711 2712- SystemACE Support: 2713 CONFIG_SYSTEMACE 2714 2715 Adding this option adds support for Xilinx SystemACE 2716 chips attached via some sort of local bus. The address 2717 of the chip must also be defined in the 2718 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 2719 2720 #define CONFIG_SYSTEMACE 2721 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 2722 2723 When SystemACE support is added, the "ace" device type 2724 becomes available to the fat commands, i.e. fatls. 2725 2726- TFTP Fixed UDP Port: 2727 CONFIG_TFTP_PORT 2728 2729 If this is defined, the environment variable tftpsrcp 2730 is used to supply the TFTP UDP source port value. 2731 If tftpsrcp isn't defined, the normal pseudo-random port 2732 number generator is used. 2733 2734 Also, the environment variable tftpdstp is used to supply 2735 the TFTP UDP destination port value. If tftpdstp isn't 2736 defined, the normal port 69 is used. 2737 2738 The purpose for tftpsrcp is to allow a TFTP server to 2739 blindly start the TFTP transfer using the pre-configured 2740 target IP address and UDP port. This has the effect of 2741 "punching through" the (Windows XP) firewall, allowing 2742 the remainder of the TFTP transfer to proceed normally. 2743 A better solution is to properly configure the firewall, 2744 but sometimes that is not allowed. 2745 2746- Hashing support: 2747 CONFIG_CMD_HASH 2748 2749 This enables a generic 'hash' command which can produce 2750 hashes / digests from a few algorithms (e.g. SHA1, SHA256). 2751 2752 CONFIG_HASH_VERIFY 2753 2754 Enable the hash verify command (hash -v). This adds to code 2755 size a little. 2756 2757 Note: There is also a sha1sum command, which should perhaps 2758 be deprecated in favour of 'hash sha1'. 2759 2760- Freescale i.MX specific commands: 2761 CONFIG_CMD_HDMIDETECT 2762 This enables 'hdmidet' command which returns true if an 2763 HDMI monitor is detected. This command is i.MX 6 specific. 2764 2765- bootcount support: 2766 CONFIG_BOOTCOUNT_LIMIT 2767 2768 This enables the bootcounter support, see: 2769 http://www.denx.de/wiki/DULG/UBootBootCountLimit 2770 2771 CONFIG_AT91SAM9XE 2772 enable special bootcounter support on at91sam9xe based boards. 2773 CONFIG_SOC_DA8XX 2774 enable special bootcounter support on da850 based boards. 2775 CONFIG_BOOTCOUNT_RAM 2776 enable support for the bootcounter in RAM 2777 CONFIG_BOOTCOUNT_I2C 2778 enable support for the bootcounter on an i2c (like RTC) device. 2779 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address 2780 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for 2781 the bootcounter. 2782 CONFIG_BOOTCOUNT_ALEN = address len 2783 2784- Show boot progress: 2785 CONFIG_SHOW_BOOT_PROGRESS 2786 2787 Defining this option allows to add some board- 2788 specific code (calling a user-provided function 2789 "show_boot_progress(int)") that enables you to show 2790 the system's boot progress on some display (for 2791 example, some LED's) on your board. At the moment, 2792 the following checkpoints are implemented: 2793 2794 2795Legacy uImage format: 2796 2797 Arg Where When 2798 1 common/cmd_bootm.c before attempting to boot an image 2799 -1 common/cmd_bootm.c Image header has bad magic number 2800 2 common/cmd_bootm.c Image header has correct magic number 2801 -2 common/cmd_bootm.c Image header has bad checksum 2802 3 common/cmd_bootm.c Image header has correct checksum 2803 -3 common/cmd_bootm.c Image data has bad checksum 2804 4 common/cmd_bootm.c Image data has correct checksum 2805 -4 common/cmd_bootm.c Image is for unsupported architecture 2806 5 common/cmd_bootm.c Architecture check OK 2807 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 2808 6 common/cmd_bootm.c Image Type check OK 2809 -6 common/cmd_bootm.c gunzip uncompression error 2810 -7 common/cmd_bootm.c Unimplemented compression type 2811 7 common/cmd_bootm.c Uncompression OK 2812 8 common/cmd_bootm.c No uncompress/copy overwrite error 2813 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 2814 2815 9 common/image.c Start initial ramdisk verification 2816 -10 common/image.c Ramdisk header has bad magic number 2817 -11 common/image.c Ramdisk header has bad checksum 2818 10 common/image.c Ramdisk header is OK 2819 -12 common/image.c Ramdisk data has bad checksum 2820 11 common/image.c Ramdisk data has correct checksum 2821 12 common/image.c Ramdisk verification complete, start loading 2822 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 2823 13 common/image.c Start multifile image verification 2824 14 common/image.c No initial ramdisk, no multifile, continue. 2825 2826 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 2827 2828 -30 arch/powerpc/lib/board.c Fatal error, hang the system 2829 -31 post/post.c POST test failed, detected by post_output_backlog() 2830 -32 post/post.c POST test failed, detected by post_run_single() 2831 2832 34 common/cmd_doc.c before loading a Image from a DOC device 2833 -35 common/cmd_doc.c Bad usage of "doc" command 2834 35 common/cmd_doc.c correct usage of "doc" command 2835 -36 common/cmd_doc.c No boot device 2836 36 common/cmd_doc.c correct boot device 2837 -37 common/cmd_doc.c Unknown Chip ID on boot device 2838 37 common/cmd_doc.c correct chip ID found, device available 2839 -38 common/cmd_doc.c Read Error on boot device 2840 38 common/cmd_doc.c reading Image header from DOC device OK 2841 -39 common/cmd_doc.c Image header has bad magic number 2842 39 common/cmd_doc.c Image header has correct magic number 2843 -40 common/cmd_doc.c Error reading Image from DOC device 2844 40 common/cmd_doc.c Image header has correct magic number 2845 41 common/cmd_ide.c before loading a Image from a IDE device 2846 -42 common/cmd_ide.c Bad usage of "ide" command 2847 42 common/cmd_ide.c correct usage of "ide" command 2848 -43 common/cmd_ide.c No boot device 2849 43 common/cmd_ide.c boot device found 2850 -44 common/cmd_ide.c Device not available 2851 44 common/cmd_ide.c Device available 2852 -45 common/cmd_ide.c wrong partition selected 2853 45 common/cmd_ide.c partition selected 2854 -46 common/cmd_ide.c Unknown partition table 2855 46 common/cmd_ide.c valid partition table found 2856 -47 common/cmd_ide.c Invalid partition type 2857 47 common/cmd_ide.c correct partition type 2858 -48 common/cmd_ide.c Error reading Image Header on boot device 2859 48 common/cmd_ide.c reading Image Header from IDE device OK 2860 -49 common/cmd_ide.c Image header has bad magic number 2861 49 common/cmd_ide.c Image header has correct magic number 2862 -50 common/cmd_ide.c Image header has bad checksum 2863 50 common/cmd_ide.c Image header has correct checksum 2864 -51 common/cmd_ide.c Error reading Image from IDE device 2865 51 common/cmd_ide.c reading Image from IDE device OK 2866 52 common/cmd_nand.c before loading a Image from a NAND device 2867 -53 common/cmd_nand.c Bad usage of "nand" command 2868 53 common/cmd_nand.c correct usage of "nand" command 2869 -54 common/cmd_nand.c No boot device 2870 54 common/cmd_nand.c boot device found 2871 -55 common/cmd_nand.c Unknown Chip ID on boot device 2872 55 common/cmd_nand.c correct chip ID found, device available 2873 -56 common/cmd_nand.c Error reading Image Header on boot device 2874 56 common/cmd_nand.c reading Image Header from NAND device OK 2875 -57 common/cmd_nand.c Image header has bad magic number 2876 57 common/cmd_nand.c Image header has correct magic number 2877 -58 common/cmd_nand.c Error reading Image from NAND device 2878 58 common/cmd_nand.c reading Image from NAND device OK 2879 2880 -60 common/env_common.c Environment has a bad CRC, using default 2881 2882 64 net/eth.c starting with Ethernet configuration. 2883 -64 net/eth.c no Ethernet found. 2884 65 net/eth.c Ethernet found. 2885 2886 -80 common/cmd_net.c usage wrong 2887 80 common/cmd_net.c before calling net_loop() 2888 -81 common/cmd_net.c some error in net_loop() occurred 2889 81 common/cmd_net.c net_loop() back without error 2890 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 2891 82 common/cmd_net.c trying automatic boot 2892 83 common/cmd_net.c running "source" command 2893 -83 common/cmd_net.c some error in automatic boot or "source" command 2894 84 common/cmd_net.c end without errors 2895 2896FIT uImage format: 2897 2898 Arg Where When 2899 100 common/cmd_bootm.c Kernel FIT Image has correct format 2900 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 2901 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 2902 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 2903 102 common/cmd_bootm.c Kernel unit name specified 2904 -103 common/cmd_bootm.c Can't get kernel subimage node offset 2905 103 common/cmd_bootm.c Found configuration node 2906 104 common/cmd_bootm.c Got kernel subimage node offset 2907 -104 common/cmd_bootm.c Kernel subimage hash verification failed 2908 105 common/cmd_bootm.c Kernel subimage hash verification OK 2909 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 2910 106 common/cmd_bootm.c Architecture check OK 2911 -106 common/cmd_bootm.c Kernel subimage has wrong type 2912 107 common/cmd_bootm.c Kernel subimage type OK 2913 -107 common/cmd_bootm.c Can't get kernel subimage data/size 2914 108 common/cmd_bootm.c Got kernel subimage data/size 2915 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 2916 -109 common/cmd_bootm.c Can't get kernel subimage type 2917 -110 common/cmd_bootm.c Can't get kernel subimage comp 2918 -111 common/cmd_bootm.c Can't get kernel subimage os 2919 -112 common/cmd_bootm.c Can't get kernel subimage load address 2920 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 2921 2922 120 common/image.c Start initial ramdisk verification 2923 -120 common/image.c Ramdisk FIT image has incorrect format 2924 121 common/image.c Ramdisk FIT image has correct format 2925 122 common/image.c No ramdisk subimage unit name, using configuration 2926 -122 common/image.c Can't get configuration for ramdisk subimage 2927 123 common/image.c Ramdisk unit name specified 2928 -124 common/image.c Can't get ramdisk subimage node offset 2929 125 common/image.c Got ramdisk subimage node offset 2930 -125 common/image.c Ramdisk subimage hash verification failed 2931 126 common/image.c Ramdisk subimage hash verification OK 2932 -126 common/image.c Ramdisk subimage for unsupported architecture 2933 127 common/image.c Architecture check OK 2934 -127 common/image.c Can't get ramdisk subimage data/size 2935 128 common/image.c Got ramdisk subimage data/size 2936 129 common/image.c Can't get ramdisk load address 2937 -129 common/image.c Got ramdisk load address 2938 2939 -130 common/cmd_doc.c Incorrect FIT image format 2940 131 common/cmd_doc.c FIT image format OK 2941 2942 -140 common/cmd_ide.c Incorrect FIT image format 2943 141 common/cmd_ide.c FIT image format OK 2944 2945 -150 common/cmd_nand.c Incorrect FIT image format 2946 151 common/cmd_nand.c FIT image format OK 2947 2948- legacy image format: 2949 CONFIG_IMAGE_FORMAT_LEGACY 2950 enables the legacy image format support in U-Boot. 2951 2952 Default: 2953 enabled if CONFIG_FIT_SIGNATURE is not defined. 2954 2955 CONFIG_DISABLE_IMAGE_LEGACY 2956 disable the legacy image format 2957 2958 This define is introduced, as the legacy image format is 2959 enabled per default for backward compatibility. 2960 2961- Standalone program support: 2962 CONFIG_STANDALONE_LOAD_ADDR 2963 2964 This option defines a board specific value for the 2965 address where standalone program gets loaded, thus 2966 overwriting the architecture dependent default 2967 settings. 2968 2969- Frame Buffer Address: 2970 CONFIG_FB_ADDR 2971 2972 Define CONFIG_FB_ADDR if you want to use specific 2973 address for frame buffer. This is typically the case 2974 when using a graphics controller has separate video 2975 memory. U-Boot will then place the frame buffer at 2976 the given address instead of dynamically reserving it 2977 in system RAM by calling lcd_setmem(), which grabs 2978 the memory for the frame buffer depending on the 2979 configured panel size. 2980 2981 Please see board_init_f function. 2982 2983- Automatic software updates via TFTP server 2984 CONFIG_UPDATE_TFTP 2985 CONFIG_UPDATE_TFTP_CNT_MAX 2986 CONFIG_UPDATE_TFTP_MSEC_MAX 2987 2988 These options enable and control the auto-update feature; 2989 for a more detailed description refer to doc/README.update. 2990 2991- MTD Support (mtdparts command, UBI support) 2992 CONFIG_MTD_DEVICE 2993 2994 Adds the MTD device infrastructure from the Linux kernel. 2995 Needed for mtdparts command support. 2996 2997 CONFIG_MTD_PARTITIONS 2998 2999 Adds the MTD partitioning infrastructure from the Linux 3000 kernel. Needed for UBI support. 3001 3002- UBI support 3003 CONFIG_CMD_UBI 3004 3005 Adds commands for interacting with MTD partitions formatted 3006 with the UBI flash translation layer 3007 3008 Requires also defining CONFIG_RBTREE 3009 3010 CONFIG_UBI_SILENCE_MSG 3011 3012 Make the verbose messages from UBI stop printing. This leaves 3013 warnings and errors enabled. 3014 3015 3016 CONFIG_MTD_UBI_WL_THRESHOLD 3017 This parameter defines the maximum difference between the highest 3018 erase counter value and the lowest erase counter value of eraseblocks 3019 of UBI devices. When this threshold is exceeded, UBI starts performing 3020 wear leveling by means of moving data from eraseblock with low erase 3021 counter to eraseblocks with high erase counter. 3022 3023 The default value should be OK for SLC NAND flashes, NOR flashes and 3024 other flashes which have eraseblock life-cycle 100000 or more. 3025 However, in case of MLC NAND flashes which typically have eraseblock 3026 life-cycle less than 10000, the threshold should be lessened (e.g., 3027 to 128 or 256, although it does not have to be power of 2). 3028 3029 default: 4096 3030 3031 CONFIG_MTD_UBI_BEB_LIMIT 3032 This option specifies the maximum bad physical eraseblocks UBI 3033 expects on the MTD device (per 1024 eraseblocks). If the 3034 underlying flash does not admit of bad eraseblocks (e.g. NOR 3035 flash), this value is ignored. 3036 3037 NAND datasheets often specify the minimum and maximum NVM 3038 (Number of Valid Blocks) for the flashes' endurance lifetime. 3039 The maximum expected bad eraseblocks per 1024 eraseblocks 3040 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)", 3041 which gives 20 for most NANDs (MaxNVB is basically the total 3042 count of eraseblocks on the chip). 3043 3044 To put it differently, if this value is 20, UBI will try to 3045 reserve about 1.9% of physical eraseblocks for bad blocks 3046 handling. And that will be 1.9% of eraseblocks on the entire 3047 NAND chip, not just the MTD partition UBI attaches. This means 3048 that if you have, say, a NAND flash chip admits maximum 40 bad 3049 eraseblocks, and it is split on two MTD partitions of the same 3050 size, UBI will reserve 40 eraseblocks when attaching a 3051 partition. 3052 3053 default: 20 3054 3055 CONFIG_MTD_UBI_FASTMAP 3056 Fastmap is a mechanism which allows attaching an UBI device 3057 in nearly constant time. Instead of scanning the whole MTD device it 3058 only has to locate a checkpoint (called fastmap) on the device. 3059 The on-flash fastmap contains all information needed to attach 3060 the device. Using fastmap makes only sense on large devices where 3061 attaching by scanning takes long. UBI will not automatically install 3062 a fastmap on old images, but you can set the UBI parameter 3063 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note 3064 that fastmap-enabled images are still usable with UBI implementations 3065 without fastmap support. On typical flash devices the whole fastmap 3066 fits into one PEB. UBI will reserve PEBs to hold two fastmaps. 3067 3068 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT 3069 Set this parameter to enable fastmap automatically on images 3070 without a fastmap. 3071 default: 0 3072 3073 CONFIG_MTD_UBI_FM_DEBUG 3074 Enable UBI fastmap debug 3075 default: 0 3076 3077- UBIFS support 3078 CONFIG_CMD_UBIFS 3079 3080 Adds commands for interacting with UBI volumes formatted as 3081 UBIFS. UBIFS is read-only in u-boot. 3082 3083 Requires UBI support as well as CONFIG_LZO 3084 3085 CONFIG_UBIFS_SILENCE_MSG 3086 3087 Make the verbose messages from UBIFS stop printing. This leaves 3088 warnings and errors enabled. 3089 3090- SPL framework 3091 CONFIG_SPL 3092 Enable building of SPL globally. 3093 3094 CONFIG_SPL_LDSCRIPT 3095 LDSCRIPT for linking the SPL binary. 3096 3097 CONFIG_SPL_MAX_FOOTPRINT 3098 Maximum size in memory allocated to the SPL, BSS included. 3099 When defined, the linker checks that the actual memory 3100 used by SPL from _start to __bss_end does not exceed it. 3101 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3102 must not be both defined at the same time. 3103 3104 CONFIG_SPL_MAX_SIZE 3105 Maximum size of the SPL image (text, data, rodata, and 3106 linker lists sections), BSS excluded. 3107 When defined, the linker checks that the actual size does 3108 not exceed it. 3109 3110 CONFIG_SPL_TEXT_BASE 3111 TEXT_BASE for linking the SPL binary. 3112 3113 CONFIG_SPL_RELOC_TEXT_BASE 3114 Address to relocate to. If unspecified, this is equal to 3115 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done). 3116 3117 CONFIG_SPL_BSS_START_ADDR 3118 Link address for the BSS within the SPL binary. 3119 3120 CONFIG_SPL_BSS_MAX_SIZE 3121 Maximum size in memory allocated to the SPL BSS. 3122 When defined, the linker checks that the actual memory used 3123 by SPL from __bss_start to __bss_end does not exceed it. 3124 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3125 must not be both defined at the same time. 3126 3127 CONFIG_SPL_STACK 3128 Adress of the start of the stack SPL will use 3129 3130 CONFIG_SPL_PANIC_ON_RAW_IMAGE 3131 When defined, SPL will panic() if the image it has 3132 loaded does not have a signature. 3133 Defining this is useful when code which loads images 3134 in SPL cannot guarantee that absolutely all read errors 3135 will be caught. 3136 An example is the LPC32XX MLC NAND driver, which will 3137 consider that a completely unreadable NAND block is bad, 3138 and thus should be skipped silently. 3139 3140 CONFIG_SPL_RELOC_STACK 3141 Adress of the start of the stack SPL will use after 3142 relocation. If unspecified, this is equal to 3143 CONFIG_SPL_STACK. 3144 3145 CONFIG_SYS_SPL_MALLOC_START 3146 Starting address of the malloc pool used in SPL. 3147 When this option is set the full malloc is used in SPL and 3148 it is set up by spl_init() and before that, the simple malloc() 3149 can be used if CONFIG_SYS_MALLOC_F is defined. 3150 3151 CONFIG_SYS_SPL_MALLOC_SIZE 3152 The size of the malloc pool used in SPL. 3153 3154 CONFIG_SPL_FRAMEWORK 3155 Enable the SPL framework under common/. This framework 3156 supports MMC, NAND and YMODEM loading of U-Boot and NAND 3157 NAND loading of the Linux Kernel. 3158 3159 CONFIG_SPL_OS_BOOT 3160 Enable booting directly to an OS from SPL. 3161 See also: doc/README.falcon 3162 3163 CONFIG_SPL_DISPLAY_PRINT 3164 For ARM, enable an optional function to print more information 3165 about the running system. 3166 3167 CONFIG_SPL_INIT_MINIMAL 3168 Arch init code should be built for a very small image 3169 3170 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION 3171 Partition on the MMC to load U-Boot from when the MMC is being 3172 used in raw mode 3173 3174 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR 3175 Sector to load kernel uImage from when MMC is being 3176 used in raw mode (for Falcon mode) 3177 3178 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR, 3179 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS 3180 Sector and number of sectors to load kernel argument 3181 parameters from when MMC is being used in raw mode 3182 (for falcon mode) 3183 3184 CONFIG_SYS_MMCSD_FS_BOOT_PARTITION 3185 Partition on the MMC to load U-Boot from when the MMC is being 3186 used in fs mode 3187 3188 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME 3189 Filename to read to load U-Boot when reading from filesystem 3190 3191 CONFIG_SPL_FS_LOAD_KERNEL_NAME 3192 Filename to read to load kernel uImage when reading 3193 from filesystem (for Falcon mode) 3194 3195 CONFIG_SPL_FS_LOAD_ARGS_NAME 3196 Filename to read to load kernel argument parameters 3197 when reading from filesystem (for Falcon mode) 3198 3199 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND 3200 Set this for NAND SPL on PPC mpc83xx targets, so that 3201 start.S waits for the rest of the SPL to load before 3202 continuing (the hardware starts execution after just 3203 loading the first page rather than the full 4K). 3204 3205 CONFIG_SPL_SKIP_RELOCATE 3206 Avoid SPL relocation 3207 3208 CONFIG_SPL_NAND_BASE 3209 Include nand_base.c in the SPL. Requires 3210 CONFIG_SPL_NAND_DRIVERS. 3211 3212 CONFIG_SPL_NAND_DRIVERS 3213 SPL uses normal NAND drivers, not minimal drivers. 3214 3215 CONFIG_SPL_NAND_ECC 3216 Include standard software ECC in the SPL 3217 3218 CONFIG_SPL_NAND_SIMPLE 3219 Support for NAND boot using simple NAND drivers that 3220 expose the cmd_ctrl() interface. 3221 3222 CONFIG_SPL_UBI 3223 Support for a lightweight UBI (fastmap) scanner and 3224 loader 3225 3226 CONFIG_SPL_NAND_RAW_ONLY 3227 Support to boot only raw u-boot.bin images. Use this only 3228 if you need to save space. 3229 3230 CONFIG_SPL_COMMON_INIT_DDR 3231 Set for common ddr init with serial presence detect in 3232 SPL binary. 3233 3234 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT, 3235 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE, 3236 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS, 3237 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE, 3238 CONFIG_SYS_NAND_ECCBYTES 3239 Defines the size and behavior of the NAND that SPL uses 3240 to read U-Boot 3241 3242 CONFIG_SPL_NAND_BOOT 3243 Add support NAND boot 3244 3245 CONFIG_SYS_NAND_U_BOOT_OFFS 3246 Location in NAND to read U-Boot from 3247 3248 CONFIG_SYS_NAND_U_BOOT_DST 3249 Location in memory to load U-Boot to 3250 3251 CONFIG_SYS_NAND_U_BOOT_SIZE 3252 Size of image to load 3253 3254 CONFIG_SYS_NAND_U_BOOT_START 3255 Entry point in loaded image to jump to 3256 3257 CONFIG_SYS_NAND_HW_ECC_OOBFIRST 3258 Define this if you need to first read the OOB and then the 3259 data. This is used, for example, on davinci platforms. 3260 3261 CONFIG_SPL_OMAP3_ID_NAND 3262 Support for an OMAP3-specific set of functions to return the 3263 ID and MFR of the first attached NAND chip, if present. 3264 3265 CONFIG_SPL_RAM_DEVICE 3266 Support for running image already present in ram, in SPL binary 3267 3268 CONFIG_SPL_PAD_TO 3269 Image offset to which the SPL should be padded before appending 3270 the SPL payload. By default, this is defined as 3271 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3272 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3273 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3274 3275 CONFIG_SPL_TARGET 3276 Final target image containing SPL and payload. Some SPLs 3277 use an arch-specific makefile fragment instead, for 3278 example if more than one image needs to be produced. 3279 3280 CONFIG_FIT_SPL_PRINT 3281 Printing information about a FIT image adds quite a bit of 3282 code to SPL. So this is normally disabled in SPL. Use this 3283 option to re-enable it. This will affect the output of the 3284 bootm command when booting a FIT image. 3285 3286- TPL framework 3287 CONFIG_TPL 3288 Enable building of TPL globally. 3289 3290 CONFIG_TPL_PAD_TO 3291 Image offset to which the TPL should be padded before appending 3292 the TPL payload. By default, this is defined as 3293 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3294 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3295 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3296 3297- Interrupt support (PPC): 3298 3299 There are common interrupt_init() and timer_interrupt() 3300 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 3301 for CPU specific initialization. interrupt_init_cpu() 3302 should set decrementer_count to appropriate value. If 3303 CPU resets decrementer automatically after interrupt 3304 (ppc4xx) it should set decrementer_count to zero. 3305 timer_interrupt() calls timer_interrupt_cpu() for CPU 3306 specific handling. If board has watchdog / status_led 3307 / other_activity_monitor it works automatically from 3308 general timer_interrupt(). 3309 3310 3311Board initialization settings: 3312------------------------------ 3313 3314During Initialization u-boot calls a number of board specific functions 3315to allow the preparation of board specific prerequisites, e.g. pin setup 3316before drivers are initialized. To enable these callbacks the 3317following configuration macros have to be defined. Currently this is 3318architecture specific, so please check arch/your_architecture/lib/board.c 3319typically in board_init_f() and board_init_r(). 3320 3321- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 3322- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 3323- CONFIG_BOARD_LATE_INIT: Call board_late_init() 3324- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 3325 3326Configuration Settings: 3327----------------------- 3328 3329- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit. 3330 Optionally it can be defined to support 64-bit memory commands. 3331 3332- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 3333 undefine this when you're short of memory. 3334 3335- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 3336 width of the commands listed in the 'help' command output. 3337 3338- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 3339 prompt for user input. 3340 3341- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 3342 3343- CONFIG_SYS_PBSIZE: Buffer size for Console output 3344 3345- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 3346 3347- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 3348 the application (usually a Linux kernel) when it is 3349 booted 3350 3351- CONFIG_SYS_BAUDRATE_TABLE: 3352 List of legal baudrate settings for this board. 3353 3354- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 3355 Begin and End addresses of the area used by the 3356 simple memory test. 3357 3358- CONFIG_SYS_ALT_MEMTEST: 3359 Enable an alternate, more extensive memory test. 3360 3361- CONFIG_SYS_MEMTEST_SCRATCH: 3362 Scratch address used by the alternate memory test 3363 You only need to set this if address zero isn't writeable 3364 3365- CONFIG_SYS_MEM_RESERVE_SECURE 3366 Only implemented for ARMv8 for now. 3367 If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory 3368 is substracted from total RAM and won't be reported to OS. 3369 This memory can be used as secure memory. A variable 3370 gd->arch.secure_ram is used to track the location. In systems 3371 the RAM base is not zero, or RAM is divided into banks, 3372 this variable needs to be recalcuated to get the address. 3373 3374- CONFIG_SYS_MEM_TOP_HIDE: 3375 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 3376 this specified memory area will get subtracted from the top 3377 (end) of RAM and won't get "touched" at all by U-Boot. By 3378 fixing up gd->ram_size the Linux kernel should gets passed 3379 the now "corrected" memory size and won't touch it either. 3380 This should work for arch/ppc and arch/powerpc. Only Linux 3381 board ports in arch/powerpc with bootwrapper support that 3382 recalculate the memory size from the SDRAM controller setup 3383 will have to get fixed in Linux additionally. 3384 3385 This option can be used as a workaround for the 440EPx/GRx 3386 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 3387 be touched. 3388 3389 WARNING: Please make sure that this value is a multiple of 3390 the Linux page size (normally 4k). If this is not the case, 3391 then the end address of the Linux memory will be located at a 3392 non page size aligned address and this could cause major 3393 problems. 3394 3395- CONFIG_SYS_LOADS_BAUD_CHANGE: 3396 Enable temporary baudrate change while serial download 3397 3398- CONFIG_SYS_SDRAM_BASE: 3399 Physical start address of SDRAM. _Must_ be 0 here. 3400 3401- CONFIG_SYS_FLASH_BASE: 3402 Physical start address of Flash memory. 3403 3404- CONFIG_SYS_MONITOR_BASE: 3405 Physical start address of boot monitor code (set by 3406 make config files to be same as the text base address 3407 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 3408 CONFIG_SYS_FLASH_BASE when booting from flash. 3409 3410- CONFIG_SYS_MONITOR_LEN: 3411 Size of memory reserved for monitor code, used to 3412 determine _at_compile_time_ (!) if the environment is 3413 embedded within the U-Boot image, or in a separate 3414 flash sector. 3415 3416- CONFIG_SYS_MALLOC_LEN: 3417 Size of DRAM reserved for malloc() use. 3418 3419- CONFIG_SYS_MALLOC_F_LEN 3420 Size of the malloc() pool for use before relocation. If 3421 this is defined, then a very simple malloc() implementation 3422 will become available before relocation. The address is just 3423 below the global data, and the stack is moved down to make 3424 space. 3425 3426 This feature allocates regions with increasing addresses 3427 within the region. calloc() is supported, but realloc() 3428 is not available. free() is supported but does nothing. 3429 The memory will be freed (or in fact just forgotten) when 3430 U-Boot relocates itself. 3431 3432- CONFIG_SYS_MALLOC_SIMPLE 3433 Provides a simple and small malloc() and calloc() for those 3434 boards which do not use the full malloc in SPL (which is 3435 enabled with CONFIG_SYS_SPL_MALLOC_START). 3436 3437- CONFIG_SYS_NONCACHED_MEMORY: 3438 Size of non-cached memory area. This area of memory will be 3439 typically located right below the malloc() area and mapped 3440 uncached in the MMU. This is useful for drivers that would 3441 otherwise require a lot of explicit cache maintenance. For 3442 some drivers it's also impossible to properly maintain the 3443 cache. For example if the regions that need to be flushed 3444 are not a multiple of the cache-line size, *and* padding 3445 cannot be allocated between the regions to align them (i.e. 3446 if the HW requires a contiguous array of regions, and the 3447 size of each region is not cache-aligned), then a flush of 3448 one region may result in overwriting data that hardware has 3449 written to another region in the same cache-line. This can 3450 happen for example in network drivers where descriptors for 3451 buffers are typically smaller than the CPU cache-line (e.g. 3452 16 bytes vs. 32 or 64 bytes). 3453 3454 Non-cached memory is only supported on 32-bit ARM at present. 3455 3456- CONFIG_SYS_BOOTM_LEN: 3457 Normally compressed uImages are limited to an 3458 uncompressed size of 8 MBytes. If this is not enough, 3459 you can define CONFIG_SYS_BOOTM_LEN in your board config file 3460 to adjust this setting to your needs. 3461 3462- CONFIG_SYS_BOOTMAPSZ: 3463 Maximum size of memory mapped by the startup code of 3464 the Linux kernel; all data that must be processed by 3465 the Linux kernel (bd_info, boot arguments, FDT blob if 3466 used) must be put below this limit, unless "bootm_low" 3467 environment variable is defined and non-zero. In such case 3468 all data for the Linux kernel must be between "bootm_low" 3469 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 3470 variable "bootm_mapsize" will override the value of 3471 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 3472 then the value in "bootm_size" will be used instead. 3473 3474- CONFIG_SYS_BOOT_RAMDISK_HIGH: 3475 Enable initrd_high functionality. If defined then the 3476 initrd_high feature is enabled and the bootm ramdisk subcommand 3477 is enabled. 3478 3479- CONFIG_SYS_BOOT_GET_CMDLINE: 3480 Enables allocating and saving kernel cmdline in space between 3481 "bootm_low" and "bootm_low" + BOOTMAPSZ. 3482 3483- CONFIG_SYS_BOOT_GET_KBD: 3484 Enables allocating and saving a kernel copy of the bd_info in 3485 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 3486 3487- CONFIG_SYS_MAX_FLASH_BANKS: 3488 Max number of Flash memory banks 3489 3490- CONFIG_SYS_MAX_FLASH_SECT: 3491 Max number of sectors on a Flash chip 3492 3493- CONFIG_SYS_FLASH_ERASE_TOUT: 3494 Timeout for Flash erase operations (in ms) 3495 3496- CONFIG_SYS_FLASH_WRITE_TOUT: 3497 Timeout for Flash write operations (in ms) 3498 3499- CONFIG_SYS_FLASH_LOCK_TOUT 3500 Timeout for Flash set sector lock bit operation (in ms) 3501 3502- CONFIG_SYS_FLASH_UNLOCK_TOUT 3503 Timeout for Flash clear lock bits operation (in ms) 3504 3505- CONFIG_SYS_FLASH_PROTECTION 3506 If defined, hardware flash sectors protection is used 3507 instead of U-Boot software protection. 3508 3509- CONFIG_SYS_DIRECT_FLASH_TFTP: 3510 3511 Enable TFTP transfers directly to flash memory; 3512 without this option such a download has to be 3513 performed in two steps: (1) download to RAM, and (2) 3514 copy from RAM to flash. 3515 3516 The two-step approach is usually more reliable, since 3517 you can check if the download worked before you erase 3518 the flash, but in some situations (when system RAM is 3519 too limited to allow for a temporary copy of the 3520 downloaded image) this option may be very useful. 3521 3522- CONFIG_SYS_FLASH_CFI: 3523 Define if the flash driver uses extra elements in the 3524 common flash structure for storing flash geometry. 3525 3526- CONFIG_FLASH_CFI_DRIVER 3527 This option also enables the building of the cfi_flash driver 3528 in the drivers directory 3529 3530- CONFIG_FLASH_CFI_MTD 3531 This option enables the building of the cfi_mtd driver 3532 in the drivers directory. The driver exports CFI flash 3533 to the MTD layer. 3534 3535- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 3536 Use buffered writes to flash. 3537 3538- CONFIG_FLASH_SPANSION_S29WS_N 3539 s29ws-n MirrorBit flash has non-standard addresses for buffered 3540 write commands. 3541 3542- CONFIG_SYS_FLASH_QUIET_TEST 3543 If this option is defined, the common CFI flash doesn't 3544 print it's warning upon not recognized FLASH banks. This 3545 is useful, if some of the configured banks are only 3546 optionally available. 3547 3548- CONFIG_FLASH_SHOW_PROGRESS 3549 If defined (must be an integer), print out countdown 3550 digits and dots. Recommended value: 45 (9..1) for 80 3551 column displays, 15 (3..1) for 40 column displays. 3552 3553- CONFIG_FLASH_VERIFY 3554 If defined, the content of the flash (destination) is compared 3555 against the source after the write operation. An error message 3556 will be printed when the contents are not identical. 3557 Please note that this option is useless in nearly all cases, 3558 since such flash programming errors usually are detected earlier 3559 while unprotecting/erasing/programming. Please only enable 3560 this option if you really know what you are doing. 3561 3562- CONFIG_SYS_RX_ETH_BUFFER: 3563 Defines the number of Ethernet receive buffers. On some 3564 Ethernet controllers it is recommended to set this value 3565 to 8 or even higher (EEPRO100 or 405 EMAC), since all 3566 buffers can be full shortly after enabling the interface 3567 on high Ethernet traffic. 3568 Defaults to 4 if not defined. 3569 3570- CONFIG_ENV_MAX_ENTRIES 3571 3572 Maximum number of entries in the hash table that is used 3573 internally to store the environment settings. The default 3574 setting is supposed to be generous and should work in most 3575 cases. This setting can be used to tune behaviour; see 3576 lib/hashtable.c for details. 3577 3578- CONFIG_ENV_FLAGS_LIST_DEFAULT 3579- CONFIG_ENV_FLAGS_LIST_STATIC 3580 Enable validation of the values given to environment variables when 3581 calling env set. Variables can be restricted to only decimal, 3582 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined, 3583 the variables can also be restricted to IP address or MAC address. 3584 3585 The format of the list is: 3586 type_attribute = [s|d|x|b|i|m] 3587 access_attribute = [a|r|o|c] 3588 attributes = type_attribute[access_attribute] 3589 entry = variable_name[:attributes] 3590 list = entry[,list] 3591 3592 The type attributes are: 3593 s - String (default) 3594 d - Decimal 3595 x - Hexadecimal 3596 b - Boolean ([1yYtT|0nNfF]) 3597 i - IP address 3598 m - MAC address 3599 3600 The access attributes are: 3601 a - Any (default) 3602 r - Read-only 3603 o - Write-once 3604 c - Change-default 3605 3606 - CONFIG_ENV_FLAGS_LIST_DEFAULT 3607 Define this to a list (string) to define the ".flags" 3608 environment variable in the default or embedded environment. 3609 3610 - CONFIG_ENV_FLAGS_LIST_STATIC 3611 Define this to a list (string) to define validation that 3612 should be done if an entry is not found in the ".flags" 3613 environment variable. To override a setting in the static 3614 list, simply add an entry for the same variable name to the 3615 ".flags" variable. 3616 3617 If CONFIG_REGEX is defined, the variable_name above is evaluated as a 3618 regular expression. This allows multiple variables to define the same 3619 flags without explicitly listing them for each variable. 3620 3621- CONFIG_ENV_ACCESS_IGNORE_FORCE 3622 If defined, don't allow the -f switch to env set override variable 3623 access flags. 3624 3625- CONFIG_USE_STDINT 3626 If stdint.h is available with your toolchain you can define this 3627 option to enable it. You can provide option 'USE_STDINT=1' when 3628 building U-Boot to enable this. 3629 3630The following definitions that deal with the placement and management 3631of environment data (variable area); in general, we support the 3632following configurations: 3633 3634- CONFIG_BUILD_ENVCRC: 3635 3636 Builds up envcrc with the target environment so that external utils 3637 may easily extract it and embed it in final U-Boot images. 3638 3639- CONFIG_ENV_IS_IN_FLASH: 3640 3641 Define this if the environment is in flash memory. 3642 3643 a) The environment occupies one whole flash sector, which is 3644 "embedded" in the text segment with the U-Boot code. This 3645 happens usually with "bottom boot sector" or "top boot 3646 sector" type flash chips, which have several smaller 3647 sectors at the start or the end. For instance, such a 3648 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 3649 such a case you would place the environment in one of the 3650 4 kB sectors - with U-Boot code before and after it. With 3651 "top boot sector" type flash chips, you would put the 3652 environment in one of the last sectors, leaving a gap 3653 between U-Boot and the environment. 3654 3655 - CONFIG_ENV_OFFSET: 3656 3657 Offset of environment data (variable area) to the 3658 beginning of flash memory; for instance, with bottom boot 3659 type flash chips the second sector can be used: the offset 3660 for this sector is given here. 3661 3662 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 3663 3664 - CONFIG_ENV_ADDR: 3665 3666 This is just another way to specify the start address of 3667 the flash sector containing the environment (instead of 3668 CONFIG_ENV_OFFSET). 3669 3670 - CONFIG_ENV_SECT_SIZE: 3671 3672 Size of the sector containing the environment. 3673 3674 3675 b) Sometimes flash chips have few, equal sized, BIG sectors. 3676 In such a case you don't want to spend a whole sector for 3677 the environment. 3678 3679 - CONFIG_ENV_SIZE: 3680 3681 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 3682 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 3683 of this flash sector for the environment. This saves 3684 memory for the RAM copy of the environment. 3685 3686 It may also save flash memory if you decide to use this 3687 when your environment is "embedded" within U-Boot code, 3688 since then the remainder of the flash sector could be used 3689 for U-Boot code. It should be pointed out that this is 3690 STRONGLY DISCOURAGED from a robustness point of view: 3691 updating the environment in flash makes it always 3692 necessary to erase the WHOLE sector. If something goes 3693 wrong before the contents has been restored from a copy in 3694 RAM, your target system will be dead. 3695 3696 - CONFIG_ENV_ADDR_REDUND 3697 CONFIG_ENV_SIZE_REDUND 3698 3699 These settings describe a second storage area used to hold 3700 a redundant copy of the environment data, so that there is 3701 a valid backup copy in case there is a power failure during 3702 a "saveenv" operation. 3703 3704BE CAREFUL! Any changes to the flash layout, and some changes to the 3705source code will make it necessary to adapt <board>/u-boot.lds* 3706accordingly! 3707 3708 3709- CONFIG_ENV_IS_IN_NVRAM: 3710 3711 Define this if you have some non-volatile memory device 3712 (NVRAM, battery buffered SRAM) which you want to use for the 3713 environment. 3714 3715 - CONFIG_ENV_ADDR: 3716 - CONFIG_ENV_SIZE: 3717 3718 These two #defines are used to determine the memory area you 3719 want to use for environment. It is assumed that this memory 3720 can just be read and written to, without any special 3721 provision. 3722 3723BE CAREFUL! The first access to the environment happens quite early 3724in U-Boot initialization (when we try to get the setting of for the 3725console baudrate). You *MUST* have mapped your NVRAM area then, or 3726U-Boot will hang. 3727 3728Please note that even with NVRAM we still use a copy of the 3729environment in RAM: we could work on NVRAM directly, but we want to 3730keep settings there always unmodified except somebody uses "saveenv" 3731to save the current settings. 3732 3733 3734- CONFIG_ENV_IS_IN_EEPROM: 3735 3736 Use this if you have an EEPROM or similar serial access 3737 device and a driver for it. 3738 3739 - CONFIG_ENV_OFFSET: 3740 - CONFIG_ENV_SIZE: 3741 3742 These two #defines specify the offset and size of the 3743 environment area within the total memory of your EEPROM. 3744 3745 - CONFIG_SYS_I2C_EEPROM_ADDR: 3746 If defined, specified the chip address of the EEPROM device. 3747 The default address is zero. 3748 3749 - CONFIG_SYS_I2C_EEPROM_BUS: 3750 If defined, specified the i2c bus of the EEPROM device. 3751 3752 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 3753 If defined, the number of bits used to address bytes in a 3754 single page in the EEPROM device. A 64 byte page, for example 3755 would require six bits. 3756 3757 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 3758 If defined, the number of milliseconds to delay between 3759 page writes. The default is zero milliseconds. 3760 3761 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 3762 The length in bytes of the EEPROM memory array address. Note 3763 that this is NOT the chip address length! 3764 3765 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 3766 EEPROM chips that implement "address overflow" are ones 3767 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 3768 address and the extra bits end up in the "chip address" bit 3769 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 3770 byte chips. 3771 3772 Note that we consider the length of the address field to 3773 still be one byte because the extra address bits are hidden 3774 in the chip address. 3775 3776 - CONFIG_SYS_EEPROM_SIZE: 3777 The size in bytes of the EEPROM device. 3778 3779 - CONFIG_ENV_EEPROM_IS_ON_I2C 3780 define this, if you have I2C and SPI activated, and your 3781 EEPROM, which holds the environment, is on the I2C bus. 3782 3783 - CONFIG_I2C_ENV_EEPROM_BUS 3784 if you have an Environment on an EEPROM reached over 3785 I2C muxes, you can define here, how to reach this 3786 EEPROM. For example: 3787 3788 #define CONFIG_I2C_ENV_EEPROM_BUS 1 3789 3790 EEPROM which holds the environment, is reached over 3791 a pca9547 i2c mux with address 0x70, channel 3. 3792 3793- CONFIG_ENV_IS_IN_DATAFLASH: 3794 3795 Define this if you have a DataFlash memory device which you 3796 want to use for the environment. 3797 3798 - CONFIG_ENV_OFFSET: 3799 - CONFIG_ENV_ADDR: 3800 - CONFIG_ENV_SIZE: 3801 3802 These three #defines specify the offset and size of the 3803 environment area within the total memory of your DataFlash placed 3804 at the specified address. 3805 3806- CONFIG_ENV_IS_IN_SPI_FLASH: 3807 3808 Define this if you have a SPI Flash memory device which you 3809 want to use for the environment. 3810 3811 - CONFIG_ENV_OFFSET: 3812 - CONFIG_ENV_SIZE: 3813 3814 These two #defines specify the offset and size of the 3815 environment area within the SPI Flash. CONFIG_ENV_OFFSET must be 3816 aligned to an erase sector boundary. 3817 3818 - CONFIG_ENV_SECT_SIZE: 3819 3820 Define the SPI flash's sector size. 3821 3822 - CONFIG_ENV_OFFSET_REDUND (optional): 3823 3824 This setting describes a second storage area of CONFIG_ENV_SIZE 3825 size used to hold a redundant copy of the environment data, so 3826 that there is a valid backup copy in case there is a power failure 3827 during a "saveenv" operation. CONFIG_ENV_OFFSET_REDUND must be 3828 aligned to an erase sector boundary. 3829 3830 - CONFIG_ENV_SPI_BUS (optional): 3831 - CONFIG_ENV_SPI_CS (optional): 3832 3833 Define the SPI bus and chip select. If not defined they will be 0. 3834 3835 - CONFIG_ENV_SPI_MAX_HZ (optional): 3836 3837 Define the SPI max work clock. If not defined then use 1MHz. 3838 3839 - CONFIG_ENV_SPI_MODE (optional): 3840 3841 Define the SPI work mode. If not defined then use SPI_MODE_3. 3842 3843- CONFIG_ENV_IS_IN_REMOTE: 3844 3845 Define this if you have a remote memory space which you 3846 want to use for the local device's environment. 3847 3848 - CONFIG_ENV_ADDR: 3849 - CONFIG_ENV_SIZE: 3850 3851 These two #defines specify the address and size of the 3852 environment area within the remote memory space. The 3853 local device can get the environment from remote memory 3854 space by SRIO or PCIE links. 3855 3856BE CAREFUL! For some special cases, the local device can not use 3857"saveenv" command. For example, the local device will get the 3858environment stored in a remote NOR flash by SRIO or PCIE link, 3859but it can not erase, write this NOR flash by SRIO or PCIE interface. 3860 3861- CONFIG_ENV_IS_IN_NAND: 3862 3863 Define this if you have a NAND device which you want to use 3864 for the environment. 3865 3866 - CONFIG_ENV_OFFSET: 3867 - CONFIG_ENV_SIZE: 3868 3869 These two #defines specify the offset and size of the environment 3870 area within the first NAND device. CONFIG_ENV_OFFSET must be 3871 aligned to an erase block boundary. 3872 3873 - CONFIG_ENV_OFFSET_REDUND (optional): 3874 3875 This setting describes a second storage area of CONFIG_ENV_SIZE 3876 size used to hold a redundant copy of the environment data, so 3877 that there is a valid backup copy in case there is a power failure 3878 during a "saveenv" operation. CONFIG_ENV_OFFSET_REDUND must be 3879 aligned to an erase block boundary. 3880 3881 - CONFIG_ENV_RANGE (optional): 3882 3883 Specifies the length of the region in which the environment 3884 can be written. This should be a multiple of the NAND device's 3885 block size. Specifying a range with more erase blocks than 3886 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 3887 the range to be avoided. 3888 3889 - CONFIG_ENV_OFFSET_OOB (optional): 3890 3891 Enables support for dynamically retrieving the offset of the 3892 environment from block zero's out-of-band data. The 3893 "nand env.oob" command can be used to record this offset. 3894 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 3895 using CONFIG_ENV_OFFSET_OOB. 3896 3897- CONFIG_NAND_ENV_DST 3898 3899 Defines address in RAM to which the nand_spl code should copy the 3900 environment. If redundant environment is used, it will be copied to 3901 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 3902 3903- CONFIG_ENV_IS_IN_UBI: 3904 3905 Define this if you have an UBI volume that you want to use for the 3906 environment. This has the benefit of wear-leveling the environment 3907 accesses, which is important on NAND. 3908 3909 - CONFIG_ENV_UBI_PART: 3910 3911 Define this to a string that is the mtd partition containing the UBI. 3912 3913 - CONFIG_ENV_UBI_VOLUME: 3914 3915 Define this to the name of the volume that you want to store the 3916 environment in. 3917 3918 - CONFIG_ENV_UBI_VOLUME_REDUND: 3919 3920 Define this to the name of another volume to store a second copy of 3921 the environment in. This will enable redundant environments in UBI. 3922 It is assumed that both volumes are in the same MTD partition. 3923 3924 - CONFIG_UBI_SILENCE_MSG 3925 - CONFIG_UBIFS_SILENCE_MSG 3926 3927 You will probably want to define these to avoid a really noisy system 3928 when storing the env in UBI. 3929 3930- CONFIG_ENV_IS_IN_FAT: 3931 Define this if you want to use the FAT file system for the environment. 3932 3933 - FAT_ENV_INTERFACE: 3934 3935 Define this to a string that is the name of the block device. 3936 3937 - FAT_ENV_DEVICE_AND_PART: 3938 3939 Define this to a string to specify the partition of the device. It can 3940 be as following: 3941 3942 "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1) 3943 - "D:P": device D partition P. Error occurs if device D has no 3944 partition table. 3945 - "D:0": device D. 3946 - "D" or "D:": device D partition 1 if device D has partition 3947 table, or the whole device D if has no partition 3948 table. 3949 - "D:auto": first partition in device D with bootable flag set. 3950 If none, first valid partition in device D. If no 3951 partition table then means device D. 3952 3953 - FAT_ENV_FILE: 3954 3955 It's a string of the FAT file name. This file use to store the 3956 environment. 3957 3958 - CONFIG_FAT_WRITE: 3959 This should be defined. Otherwise it cannot save the environment file. 3960 3961- CONFIG_ENV_IS_IN_MMC: 3962 3963 Define this if you have an MMC device which you want to use for the 3964 environment. 3965 3966 - CONFIG_SYS_MMC_ENV_DEV: 3967 3968 Specifies which MMC device the environment is stored in. 3969 3970 - CONFIG_SYS_MMC_ENV_PART (optional): 3971 3972 Specifies which MMC partition the environment is stored in. If not 3973 set, defaults to partition 0, the user area. Common values might be 3974 1 (first MMC boot partition), 2 (second MMC boot partition). 3975 3976 - CONFIG_ENV_OFFSET: 3977 - CONFIG_ENV_SIZE: 3978 3979 These two #defines specify the offset and size of the environment 3980 area within the specified MMC device. 3981 3982 If offset is positive (the usual case), it is treated as relative to 3983 the start of the MMC partition. If offset is negative, it is treated 3984 as relative to the end of the MMC partition. This can be useful if 3985 your board may be fitted with different MMC devices, which have 3986 different sizes for the MMC partitions, and you always want the 3987 environment placed at the very end of the partition, to leave the 3988 maximum possible space before it, to store other data. 3989 3990 These two values are in units of bytes, but must be aligned to an 3991 MMC sector boundary. 3992 3993 - CONFIG_ENV_OFFSET_REDUND (optional): 3994 3995 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to 3996 hold a redundant copy of the environment data. This provides a 3997 valid backup copy in case the other copy is corrupted, e.g. due 3998 to a power failure during a "saveenv" operation. 3999 4000 This value may also be positive or negative; this is handled in the 4001 same way as CONFIG_ENV_OFFSET. 4002 4003 This value is also in units of bytes, but must also be aligned to 4004 an MMC sector boundary. 4005 4006 - CONFIG_ENV_SIZE_REDUND (optional): 4007 4008 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is 4009 set. If this value is set, it must be set to the same value as 4010 CONFIG_ENV_SIZE. 4011 4012- CONFIG_SYS_SPI_INIT_OFFSET 4013 4014 Defines offset to the initial SPI buffer area in DPRAM. The 4015 area is used at an early stage (ROM part) if the environment 4016 is configured to reside in the SPI EEPROM: We need a 520 byte 4017 scratch DPRAM area. It is used between the two initialization 4018 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 4019 to be a good choice since it makes it far enough from the 4020 start of the data area as well as from the stack pointer. 4021 4022Please note that the environment is read-only until the monitor 4023has been relocated to RAM and a RAM copy of the environment has been 4024created; also, when using EEPROM you will have to use getenv_f() 4025until then to read environment variables. 4026 4027The environment is protected by a CRC32 checksum. Before the monitor 4028is relocated into RAM, as a result of a bad CRC you will be working 4029with the compiled-in default environment - *silently*!!! [This is 4030necessary, because the first environment variable we need is the 4031"baudrate" setting for the console - if we have a bad CRC, we don't 4032have any device yet where we could complain.] 4033 4034Note: once the monitor has been relocated, then it will complain if 4035the default environment is used; a new CRC is computed as soon as you 4036use the "saveenv" command to store a valid environment. 4037 4038- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 4039 Echo the inverted Ethernet link state to the fault LED. 4040 4041 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 4042 also needs to be defined. 4043 4044- CONFIG_SYS_FAULT_MII_ADDR: 4045 MII address of the PHY to check for the Ethernet link state. 4046 4047- CONFIG_NS16550_MIN_FUNCTIONS: 4048 Define this if you desire to only have use of the NS16550_init 4049 and NS16550_putc functions for the serial driver located at 4050 drivers/serial/ns16550.c. This option is useful for saving 4051 space for already greatly restricted images, including but not 4052 limited to NAND_SPL configurations. 4053 4054- CONFIG_DISPLAY_BOARDINFO 4055 Display information about the board that U-Boot is running on 4056 when U-Boot starts up. The board function checkboard() is called 4057 to do this. 4058 4059- CONFIG_DISPLAY_BOARDINFO_LATE 4060 Similar to the previous option, but display this information 4061 later, once stdio is running and output goes to the LCD, if 4062 present. 4063 4064- CONFIG_BOARD_SIZE_LIMIT: 4065 Maximum size of the U-Boot image. When defined, the 4066 build system checks that the actual size does not 4067 exceed it. 4068 4069Low Level (hardware related) configuration options: 4070--------------------------------------------------- 4071 4072- CONFIG_SYS_CACHELINE_SIZE: 4073 Cache Line Size of the CPU. 4074 4075- CONFIG_SYS_DEFAULT_IMMR: 4076 Default address of the IMMR after system reset. 4077 4078 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 4079 and RPXsuper) to be able to adjust the position of 4080 the IMMR register after a reset. 4081 4082- CONFIG_SYS_CCSRBAR_DEFAULT: 4083 Default (power-on reset) physical address of CCSR on Freescale 4084 PowerPC SOCs. 4085 4086- CONFIG_SYS_CCSRBAR: 4087 Virtual address of CCSR. On a 32-bit build, this is typically 4088 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 4089 4090 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 4091 for cross-platform code that uses that macro instead. 4092 4093- CONFIG_SYS_CCSRBAR_PHYS: 4094 Physical address of CCSR. CCSR can be relocated to a new 4095 physical address, if desired. In this case, this macro should 4096 be set to that address. Otherwise, it should be set to the 4097 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 4098 is typically relocated on 36-bit builds. It is recommended 4099 that this macro be defined via the _HIGH and _LOW macros: 4100 4101 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 4102 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 4103 4104- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 4105 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 4106 either 0 (32-bit build) or 0xF (36-bit build). This macro is 4107 used in assembly code, so it must not contain typecasts or 4108 integer size suffixes (e.g. "ULL"). 4109 4110- CONFIG_SYS_CCSRBAR_PHYS_LOW: 4111 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 4112 used in assembly code, so it must not contain typecasts or 4113 integer size suffixes (e.g. "ULL"). 4114 4115- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 4116 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 4117 forced to a value that ensures that CCSR is not relocated. 4118 4119- Floppy Disk Support: 4120 CONFIG_SYS_FDC_DRIVE_NUMBER 4121 4122 the default drive number (default value 0) 4123 4124 CONFIG_SYS_ISA_IO_STRIDE 4125 4126 defines the spacing between FDC chipset registers 4127 (default value 1) 4128 4129 CONFIG_SYS_ISA_IO_OFFSET 4130 4131 defines the offset of register from address. It 4132 depends on which part of the data bus is connected to 4133 the FDC chipset. (default value 0) 4134 4135 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 4136 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 4137 default value. 4138 4139 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 4140 fdc_hw_init() is called at the beginning of the FDC 4141 setup. fdc_hw_init() must be provided by the board 4142 source code. It is used to make hardware-dependent 4143 initializations. 4144 4145- CONFIG_IDE_AHB: 4146 Most IDE controllers were designed to be connected with PCI 4147 interface. Only few of them were designed for AHB interface. 4148 When software is doing ATA command and data transfer to 4149 IDE devices through IDE-AHB controller, some additional 4150 registers accessing to these kind of IDE-AHB controller 4151 is required. 4152 4153- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 4154 DO NOT CHANGE unless you know exactly what you're 4155 doing! (11-4) [MPC8xx/82xx systems only] 4156 4157- CONFIG_SYS_INIT_RAM_ADDR: 4158 4159 Start address of memory area that can be used for 4160 initial data and stack; please note that this must be 4161 writable memory that is working WITHOUT special 4162 initialization, i. e. you CANNOT use normal RAM which 4163 will become available only after programming the 4164 memory controller and running certain initialization 4165 sequences. 4166 4167 U-Boot uses the following memory types: 4168 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 4169 - MPC824X: data cache 4170 - PPC4xx: data cache 4171 4172- CONFIG_SYS_GBL_DATA_OFFSET: 4173 4174 Offset of the initial data structure in the memory 4175 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 4176 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 4177 data is located at the end of the available space 4178 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 4179 GENERATED_GBL_DATA_SIZE), and the initial stack is just 4180 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 4181 CONFIG_SYS_GBL_DATA_OFFSET) downward. 4182 4183 Note: 4184 On the MPC824X (or other systems that use the data 4185 cache for initial memory) the address chosen for 4186 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 4187 point to an otherwise UNUSED address space between 4188 the top of RAM and the start of the PCI space. 4189 4190- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 4191 4192- CONFIG_SYS_SYPCR: System Protection Control (11-9) 4193 4194- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 4195 4196- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 4197 4198- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 4199 4200- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 4201 4202- CONFIG_SYS_OR_TIMING_SDRAM: 4203 SDRAM timing 4204 4205- CONFIG_SYS_MAMR_PTA: 4206 periodic timer for refresh 4207 4208- CONFIG_SYS_DER: Debug Event Register (37-47) 4209 4210- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 4211 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 4212 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 4213 CONFIG_SYS_BR1_PRELIM: 4214 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 4215 4216- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 4217 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 4218 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 4219 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 4220 4221- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 4222 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 4223 Machine Mode Register and Memory Periodic Timer 4224 Prescaler definitions (SDRAM timing) 4225 4226- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 4227 enable I2C microcode relocation patch (MPC8xx); 4228 define relocation offset in DPRAM [DSP2] 4229 4230- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 4231 enable SMC microcode relocation patch (MPC8xx); 4232 define relocation offset in DPRAM [SMC1] 4233 4234- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 4235 enable SPI microcode relocation patch (MPC8xx); 4236 define relocation offset in DPRAM [SCC4] 4237 4238- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 4239 Offset of the bootmode word in DPRAM used by post 4240 (Power On Self Tests). This definition overrides 4241 #define'd default value in commproc.h resp. 4242 cpm_8260.h. 4243 4244- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 4245 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 4246 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 4247 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 4248 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 4249 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 4250 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 4251 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 4252 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 4253 4254- CONFIG_PCI_DISABLE_PCIE: 4255 Disable PCI-Express on systems where it is supported but not 4256 required. 4257 4258- CONFIG_PCI_ENUM_ONLY 4259 Only scan through and get the devices on the buses. 4260 Don't do any setup work, presumably because someone or 4261 something has already done it, and we don't need to do it 4262 a second time. Useful for platforms that are pre-booted 4263 by coreboot or similar. 4264 4265- CONFIG_PCI_INDIRECT_BRIDGE: 4266 Enable support for indirect PCI bridges. 4267 4268- CONFIG_SYS_SRIO: 4269 Chip has SRIO or not 4270 4271- CONFIG_SRIO1: 4272 Board has SRIO 1 port available 4273 4274- CONFIG_SRIO2: 4275 Board has SRIO 2 port available 4276 4277- CONFIG_SRIO_PCIE_BOOT_MASTER 4278 Board can support master function for Boot from SRIO and PCIE 4279 4280- CONFIG_SYS_SRIOn_MEM_VIRT: 4281 Virtual Address of SRIO port 'n' memory region 4282 4283- CONFIG_SYS_SRIOn_MEM_PHYS: 4284 Physical Address of SRIO port 'n' memory region 4285 4286- CONFIG_SYS_SRIOn_MEM_SIZE: 4287 Size of SRIO port 'n' memory region 4288 4289- CONFIG_SYS_NAND_BUSWIDTH_16BIT 4290 Defined to tell the NAND controller that the NAND chip is using 4291 a 16 bit bus. 4292 Not all NAND drivers use this symbol. 4293 Example of drivers that use it: 4294 - drivers/mtd/nand/ndfc.c 4295 - drivers/mtd/nand/mxc_nand.c 4296 4297- CONFIG_SYS_NDFC_EBC0_CFG 4298 Sets the EBC0_CFG register for the NDFC. If not defined 4299 a default value will be used. 4300 4301- CONFIG_SPD_EEPROM 4302 Get DDR timing information from an I2C EEPROM. Common 4303 with pluggable memory modules such as SODIMMs 4304 4305 SPD_EEPROM_ADDRESS 4306 I2C address of the SPD EEPROM 4307 4308- CONFIG_SYS_SPD_BUS_NUM 4309 If SPD EEPROM is on an I2C bus other than the first 4310 one, specify here. Note that the value must resolve 4311 to something your driver can deal with. 4312 4313- CONFIG_SYS_DDR_RAW_TIMING 4314 Get DDR timing information from other than SPD. Common with 4315 soldered DDR chips onboard without SPD. DDR raw timing 4316 parameters are extracted from datasheet and hard-coded into 4317 header files or board specific files. 4318 4319- CONFIG_FSL_DDR_INTERACTIVE 4320 Enable interactive DDR debugging. See doc/README.fsl-ddr. 4321 4322- CONFIG_FSL_DDR_SYNC_REFRESH 4323 Enable sync of refresh for multiple controllers. 4324 4325- CONFIG_FSL_DDR_BIST 4326 Enable built-in memory test for Freescale DDR controllers. 4327 4328- CONFIG_SYS_83XX_DDR_USES_CS0 4329 Only for 83xx systems. If specified, then DDR should 4330 be configured using CS0 and CS1 instead of CS2 and CS3. 4331 4332- CONFIG_ETHER_ON_FEC[12] 4333 Define to enable FEC[12] on a 8xx series processor. 4334 4335- CONFIG_FEC[12]_PHY 4336 Define to the hardcoded PHY address which corresponds 4337 to the given FEC; i. e. 4338 #define CONFIG_FEC1_PHY 4 4339 means that the PHY with address 4 is connected to FEC1 4340 4341 When set to -1, means to probe for first available. 4342 4343- CONFIG_FEC[12]_PHY_NORXERR 4344 The PHY does not have a RXERR line (RMII only). 4345 (so program the FEC to ignore it). 4346 4347- CONFIG_RMII 4348 Enable RMII mode for all FECs. 4349 Note that this is a global option, we can't 4350 have one FEC in standard MII mode and another in RMII mode. 4351 4352- CONFIG_CRC32_VERIFY 4353 Add a verify option to the crc32 command. 4354 The syntax is: 4355 4356 => crc32 -v <address> <count> <crc32> 4357 4358 Where address/count indicate a memory area 4359 and crc32 is the correct crc32 which the 4360 area should have. 4361 4362- CONFIG_LOOPW 4363 Add the "loopw" memory command. This only takes effect if 4364 the memory commands are activated globally (CONFIG_CMD_MEM). 4365 4366- CONFIG_MX_CYCLIC 4367 Add the "mdc" and "mwc" memory commands. These are cyclic 4368 "md/mw" commands. 4369 Examples: 4370 4371 => mdc.b 10 4 500 4372 This command will print 4 bytes (10,11,12,13) each 500 ms. 4373 4374 => mwc.l 100 12345678 10 4375 This command will write 12345678 to address 100 all 10 ms. 4376 4377 This only takes effect if the memory commands are activated 4378 globally (CONFIG_CMD_MEM). 4379 4380- CONFIG_SKIP_LOWLEVEL_INIT 4381 [ARM, NDS32, MIPS only] If this variable is defined, then certain 4382 low level initializations (like setting up the memory 4383 controller) are omitted and/or U-Boot does not 4384 relocate itself into RAM. 4385 4386 Normally this variable MUST NOT be defined. The only 4387 exception is when U-Boot is loaded (to RAM) by some 4388 other boot loader or by a debugger which performs 4389 these initializations itself. 4390 4391- CONFIG_SKIP_LOWLEVEL_INIT_ONLY 4392 [ARM926EJ-S only] This allows just the call to lowlevel_init() 4393 to be skipped. The normal CP15 init (such as enabling the 4394 instruction cache) is still performed. 4395 4396- CONFIG_SPL_BUILD 4397 Modifies the behaviour of start.S when compiling a loader 4398 that is executed before the actual U-Boot. E.g. when 4399 compiling a NAND SPL. 4400 4401- CONFIG_TPL_BUILD 4402 Modifies the behaviour of start.S when compiling a loader 4403 that is executed after the SPL and before the actual U-Boot. 4404 It is loaded by the SPL. 4405 4406- CONFIG_SYS_MPC85XX_NO_RESETVEC 4407 Only for 85xx systems. If this variable is specified, the section 4408 .resetvec is not kept and the section .bootpg is placed in the 4409 previous 4k of the .text section. 4410 4411- CONFIG_ARCH_MAP_SYSMEM 4412 Generally U-Boot (and in particular the md command) uses 4413 effective address. It is therefore not necessary to regard 4414 U-Boot address as virtual addresses that need to be translated 4415 to physical addresses. However, sandbox requires this, since 4416 it maintains its own little RAM buffer which contains all 4417 addressable memory. This option causes some memory accesses 4418 to be mapped through map_sysmem() / unmap_sysmem(). 4419 4420- CONFIG_X86_RESET_VECTOR 4421 If defined, the x86 reset vector code is included. This is not 4422 needed when U-Boot is running from Coreboot. 4423 4424- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC: 4425 Enables the RTC32K OSC on AM33xx based plattforms 4426 4427- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE 4428 Option to disable subpage write in NAND driver 4429 driver that uses this: 4430 drivers/mtd/nand/davinci_nand.c 4431 4432Freescale QE/FMAN Firmware Support: 4433----------------------------------- 4434 4435The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 4436loading of "firmware", which is encoded in the QE firmware binary format. 4437This firmware often needs to be loaded during U-Boot booting, so macros 4438are used to identify the storage device (NOR flash, SPI, etc) and the address 4439within that device. 4440 4441- CONFIG_SYS_FMAN_FW_ADDR 4442 The address in the storage device where the FMAN microcode is located. The 4443 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4444 is also specified. 4445 4446- CONFIG_SYS_QE_FW_ADDR 4447 The address in the storage device where the QE microcode is located. The 4448 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4449 is also specified. 4450 4451- CONFIG_SYS_QE_FMAN_FW_LENGTH 4452 The maximum possible size of the firmware. The firmware binary format 4453 has a field that specifies the actual size of the firmware, but it 4454 might not be possible to read any part of the firmware unless some 4455 local storage is allocated to hold the entire firmware first. 4456 4457- CONFIG_SYS_QE_FMAN_FW_IN_NOR 4458 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 4459 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 4460 virtual address in NOR flash. 4461 4462- CONFIG_SYS_QE_FMAN_FW_IN_NAND 4463 Specifies that QE/FMAN firmware is located in NAND flash. 4464 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 4465 4466- CONFIG_SYS_QE_FMAN_FW_IN_MMC 4467 Specifies that QE/FMAN firmware is located on the primary SD/MMC 4468 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 4469 4470- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE 4471 Specifies that QE/FMAN firmware is located in the remote (master) 4472 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which 4473 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound 4474 window->master inbound window->master LAW->the ucode address in 4475 master's memory space. 4476 4477Freescale Layerscape Management Complex Firmware Support: 4478--------------------------------------------------------- 4479The Freescale Layerscape Management Complex (MC) supports the loading of 4480"firmware". 4481This firmware often needs to be loaded during U-Boot booting, so macros 4482are used to identify the storage device (NOR flash, SPI, etc) and the address 4483within that device. 4484 4485- CONFIG_FSL_MC_ENET 4486 Enable the MC driver for Layerscape SoCs. 4487 4488Freescale Layerscape Debug Server Support: 4489------------------------------------------- 4490The Freescale Layerscape Debug Server Support supports the loading of 4491"Debug Server firmware" and triggering SP boot-rom. 4492This firmware often needs to be loaded during U-Boot booting. 4493 4494- CONFIG_SYS_MC_RSV_MEM_ALIGN 4495 Define alignment of reserved memory MC requires 4496 4497Reproducible builds 4498------------------- 4499 4500In order to achieve reproducible builds, timestamps used in the U-Boot build 4501process have to be set to a fixed value. 4502 4503This is done using the SOURCE_DATE_EPOCH environment variable. 4504SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration 4505option for U-Boot or an environment variable in U-Boot. 4506 4507SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC. 4508 4509Building the Software: 4510====================== 4511 4512Building U-Boot has been tested in several native build environments 4513and in many different cross environments. Of course we cannot support 4514all possibly existing versions of cross development tools in all 4515(potentially obsolete) versions. In case of tool chain problems we 4516recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 4517which is extensively used to build and test U-Boot. 4518 4519If you are not using a native environment, it is assumed that you 4520have GNU cross compiling tools available in your path. In this case, 4521you must set the environment variable CROSS_COMPILE in your shell. 4522Note that no changes to the Makefile or any other source files are 4523necessary. For example using the ELDK on a 4xx CPU, please enter: 4524 4525 $ CROSS_COMPILE=ppc_4xx- 4526 $ export CROSS_COMPILE 4527 4528Note: If you wish to generate Windows versions of the utilities in 4529 the tools directory you can use the MinGW toolchain 4530 (http://www.mingw.org). Set your HOST tools to the MinGW 4531 toolchain and execute 'make tools'. For example: 4532 4533 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 4534 4535 Binaries such as tools/mkimage.exe will be created which can 4536 be executed on computers running Windows. 4537 4538U-Boot is intended to be simple to build. After installing the 4539sources you must configure U-Boot for one specific board type. This 4540is done by typing: 4541 4542 make NAME_defconfig 4543 4544where "NAME_defconfig" is the name of one of the existing configu- 4545rations; see boards.cfg for supported names. 4546 4547Note: for some board special configuration names may exist; check if 4548 additional information is available from the board vendor; for 4549 instance, the TQM823L systems are available without (standard) 4550 or with LCD support. You can select such additional "features" 4551 when choosing the configuration, i. e. 4552 4553 make TQM823L_defconfig 4554 - will configure for a plain TQM823L, i. e. no LCD support 4555 4556 make TQM823L_LCD_defconfig 4557 - will configure for a TQM823L with U-Boot console on LCD 4558 4559 etc. 4560 4561 4562Finally, type "make all", and you should get some working U-Boot 4563images ready for download to / installation on your system: 4564 4565- "u-boot.bin" is a raw binary image 4566- "u-boot" is an image in ELF binary format 4567- "u-boot.srec" is in Motorola S-Record format 4568 4569By default the build is performed locally and the objects are saved 4570in the source directory. One of the two methods can be used to change 4571this behavior and build U-Boot to some external directory: 4572 45731. Add O= to the make command line invocations: 4574 4575 make O=/tmp/build distclean 4576 make O=/tmp/build NAME_defconfig 4577 make O=/tmp/build all 4578 45792. Set environment variable KBUILD_OUTPUT to point to the desired location: 4580 4581 export KBUILD_OUTPUT=/tmp/build 4582 make distclean 4583 make NAME_defconfig 4584 make all 4585 4586Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment 4587variable. 4588 4589 4590Please be aware that the Makefiles assume you are using GNU make, so 4591for instance on NetBSD you might need to use "gmake" instead of 4592native "make". 4593 4594 4595If the system board that you have is not listed, then you will need 4596to port U-Boot to your hardware platform. To do this, follow these 4597steps: 4598 45991. Create a new directory to hold your board specific code. Add any 4600 files you need. In your board directory, you will need at least 4601 the "Makefile" and a "<board>.c". 46022. Create a new configuration file "include/configs/<board>.h" for 4603 your board. 46043. If you're porting U-Boot to a new CPU, then also create a new 4605 directory to hold your CPU specific code. Add any files you need. 46064. Run "make <board>_defconfig" with your new name. 46075. Type "make", and you should get a working "u-boot.srec" file 4608 to be installed on your target system. 46096. Debug and solve any problems that might arise. 4610 [Of course, this last step is much harder than it sounds.] 4611 4612 4613Testing of U-Boot Modifications, Ports to New Hardware, etc.: 4614============================================================== 4615 4616If you have modified U-Boot sources (for instance added a new board 4617or support for new devices, a new CPU, etc.) you are expected to 4618provide feedback to the other developers. The feedback normally takes 4619the form of a "patch", i. e. a context diff against a certain (latest 4620official or latest in the git repository) version of U-Boot sources. 4621 4622But before you submit such a patch, please verify that your modifi- 4623cation did not break existing code. At least make sure that *ALL* of 4624the supported boards compile WITHOUT ANY compiler warnings. To do so, 4625just run the buildman script (tools/buildman/buildman), which will 4626configure and build U-Boot for ALL supported system. Be warned, this 4627will take a while. Please see the buildman README, or run 'buildman -H' 4628for documentation. 4629 4630 4631See also "U-Boot Porting Guide" below. 4632 4633 4634Monitor Commands - Overview: 4635============================ 4636 4637go - start application at address 'addr' 4638run - run commands in an environment variable 4639bootm - boot application image from memory 4640bootp - boot image via network using BootP/TFTP protocol 4641bootz - boot zImage from memory 4642tftpboot- boot image via network using TFTP protocol 4643 and env variables "ipaddr" and "serverip" 4644 (and eventually "gatewayip") 4645tftpput - upload a file via network using TFTP protocol 4646rarpboot- boot image via network using RARP/TFTP protocol 4647diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 4648loads - load S-Record file over serial line 4649loadb - load binary file over serial line (kermit mode) 4650md - memory display 4651mm - memory modify (auto-incrementing) 4652nm - memory modify (constant address) 4653mw - memory write (fill) 4654cp - memory copy 4655cmp - memory compare 4656crc32 - checksum calculation 4657i2c - I2C sub-system 4658sspi - SPI utility commands 4659base - print or set address offset 4660printenv- print environment variables 4661setenv - set environment variables 4662saveenv - save environment variables to persistent storage 4663protect - enable or disable FLASH write protection 4664erase - erase FLASH memory 4665flinfo - print FLASH memory information 4666nand - NAND memory operations (see doc/README.nand) 4667bdinfo - print Board Info structure 4668iminfo - print header information for application image 4669coninfo - print console devices and informations 4670ide - IDE sub-system 4671loop - infinite loop on address range 4672loopw - infinite write loop on address range 4673mtest - simple RAM test 4674icache - enable or disable instruction cache 4675dcache - enable or disable data cache 4676reset - Perform RESET of the CPU 4677echo - echo args to console 4678version - print monitor version 4679help - print online help 4680? - alias for 'help' 4681 4682 4683Monitor Commands - Detailed Description: 4684======================================== 4685 4686TODO. 4687 4688For now: just type "help <command>". 4689 4690 4691Environment Variables: 4692====================== 4693 4694U-Boot supports user configuration using Environment Variables which 4695can be made persistent by saving to Flash memory. 4696 4697Environment Variables are set using "setenv", printed using 4698"printenv", and saved to Flash using "saveenv". Using "setenv" 4699without a value can be used to delete a variable from the 4700environment. As long as you don't save the environment you are 4701working with an in-memory copy. In case the Flash area containing the 4702environment is erased by accident, a default environment is provided. 4703 4704Some configuration options can be set using Environment Variables. 4705 4706List of environment variables (most likely not complete): 4707 4708 baudrate - see CONFIG_BAUDRATE 4709 4710 bootdelay - see CONFIG_BOOTDELAY 4711 4712 bootcmd - see CONFIG_BOOTCOMMAND 4713 4714 bootargs - Boot arguments when booting an RTOS image 4715 4716 bootfile - Name of the image to load with TFTP 4717 4718 bootm_low - Memory range available for image processing in the bootm 4719 command can be restricted. This variable is given as 4720 a hexadecimal number and defines lowest address allowed 4721 for use by the bootm command. See also "bootm_size" 4722 environment variable. Address defined by "bootm_low" is 4723 also the base of the initial memory mapping for the Linux 4724 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 4725 bootm_mapsize. 4726 4727 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 4728 This variable is given as a hexadecimal number and it 4729 defines the size of the memory region starting at base 4730 address bootm_low that is accessible by the Linux kernel 4731 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 4732 as the default value if it is defined, and bootm_size is 4733 used otherwise. 4734 4735 bootm_size - Memory range available for image processing in the bootm 4736 command can be restricted. This variable is given as 4737 a hexadecimal number and defines the size of the region 4738 allowed for use by the bootm command. See also "bootm_low" 4739 environment variable. 4740 4741 updatefile - Location of the software update file on a TFTP server, used 4742 by the automatic software update feature. Please refer to 4743 documentation in doc/README.update for more details. 4744 4745 autoload - if set to "no" (any string beginning with 'n'), 4746 "bootp" will just load perform a lookup of the 4747 configuration from the BOOTP server, but not try to 4748 load any image using TFTP 4749 4750 autostart - if set to "yes", an image loaded using the "bootp", 4751 "rarpboot", "tftpboot" or "diskboot" commands will 4752 be automatically started (by internally calling 4753 "bootm") 4754 4755 If set to "no", a standalone image passed to the 4756 "bootm" command will be copied to the load address 4757 (and eventually uncompressed), but NOT be started. 4758 This can be used to load and uncompress arbitrary 4759 data. 4760 4761 fdt_high - if set this restricts the maximum address that the 4762 flattened device tree will be copied into upon boot. 4763 For example, if you have a system with 1 GB memory 4764 at physical address 0x10000000, while Linux kernel 4765 only recognizes the first 704 MB as low memory, you 4766 may need to set fdt_high as 0x3C000000 to have the 4767 device tree blob be copied to the maximum address 4768 of the 704 MB low memory, so that Linux kernel can 4769 access it during the boot procedure. 4770 4771 If this is set to the special value 0xFFFFFFFF then 4772 the fdt will not be copied at all on boot. For this 4773 to work it must reside in writable memory, have 4774 sufficient padding on the end of it for u-boot to 4775 add the information it needs into it, and the memory 4776 must be accessible by the kernel. 4777 4778 fdtcontroladdr- if set this is the address of the control flattened 4779 device tree used by U-Boot when CONFIG_OF_CONTROL is 4780 defined. 4781 4782 i2cfast - (PPC405GP|PPC405EP only) 4783 if set to 'y' configures Linux I2C driver for fast 4784 mode (400kHZ). This environment variable is used in 4785 initialization code. So, for changes to be effective 4786 it must be saved and board must be reset. 4787 4788 initrd_high - restrict positioning of initrd images: 4789 If this variable is not set, initrd images will be 4790 copied to the highest possible address in RAM; this 4791 is usually what you want since it allows for 4792 maximum initrd size. If for some reason you want to 4793 make sure that the initrd image is loaded below the 4794 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 4795 variable to a value of "no" or "off" or "0". 4796 Alternatively, you can set it to a maximum upper 4797 address to use (U-Boot will still check that it 4798 does not overwrite the U-Boot stack and data). 4799 4800 For instance, when you have a system with 16 MB 4801 RAM, and want to reserve 4 MB from use by Linux, 4802 you can do this by adding "mem=12M" to the value of 4803 the "bootargs" variable. However, now you must make 4804 sure that the initrd image is placed in the first 4805 12 MB as well - this can be done with 4806 4807 setenv initrd_high 00c00000 4808 4809 If you set initrd_high to 0xFFFFFFFF, this is an 4810 indication to U-Boot that all addresses are legal 4811 for the Linux kernel, including addresses in flash 4812 memory. In this case U-Boot will NOT COPY the 4813 ramdisk at all. This may be useful to reduce the 4814 boot time on your system, but requires that this 4815 feature is supported by your Linux kernel. 4816 4817 ipaddr - IP address; needed for tftpboot command 4818 4819 loadaddr - Default load address for commands like "bootp", 4820 "rarpboot", "tftpboot", "loadb" or "diskboot" 4821 4822 loads_echo - see CONFIG_LOADS_ECHO 4823 4824 serverip - TFTP server IP address; needed for tftpboot command 4825 4826 bootretry - see CONFIG_BOOT_RETRY_TIME 4827 4828 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 4829 4830 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 4831 4832 ethprime - controls which interface is used first. 4833 4834 ethact - controls which interface is currently active. 4835 For example you can do the following 4836 4837 => setenv ethact FEC 4838 => ping 192.168.0.1 # traffic sent on FEC 4839 => setenv ethact SCC 4840 => ping 10.0.0.1 # traffic sent on SCC 4841 4842 ethrotate - When set to "no" U-Boot does not go through all 4843 available network interfaces. 4844 It just stays at the currently selected interface. 4845 4846 netretry - When set to "no" each network operation will 4847 either succeed or fail without retrying. 4848 When set to "once" the network operation will 4849 fail when all the available network interfaces 4850 are tried once without success. 4851 Useful on scripts which control the retry operation 4852 themselves. 4853 4854 npe_ucode - set load address for the NPE microcode 4855 4856 silent_linux - If set then Linux will be told to boot silently, by 4857 changing the console to be empty. If "yes" it will be 4858 made silent. If "no" it will not be made silent. If 4859 unset, then it will be made silent if the U-Boot console 4860 is silent. 4861 4862 tftpsrcp - If this is set, the value is used for TFTP's 4863 UDP source port. 4864 4865 tftpdstp - If this is set, the value is used for TFTP's UDP 4866 destination port instead of the Well Know Port 69. 4867 4868 tftpblocksize - Block size to use for TFTP transfers; if not set, 4869 we use the TFTP server's default block size 4870 4871 tftptimeout - Retransmission timeout for TFTP packets (in milli- 4872 seconds, minimum value is 1000 = 1 second). Defines 4873 when a packet is considered to be lost so it has to 4874 be retransmitted. The default is 5000 = 5 seconds. 4875 Lowering this value may make downloads succeed 4876 faster in networks with high packet loss rates or 4877 with unreliable TFTP servers. 4878 4879 tftptimeoutcountmax - maximum count of TFTP timeouts (no 4880 unit, minimum value = 0). Defines how many timeouts 4881 can happen during a single file transfer before that 4882 transfer is aborted. The default is 10, and 0 means 4883 'no timeouts allowed'. Increasing this value may help 4884 downloads succeed with high packet loss rates, or with 4885 unreliable TFTP servers or client hardware. 4886 4887 vlan - When set to a value < 4095 the traffic over 4888 Ethernet is encapsulated/received over 802.1q 4889 VLAN tagged frames. 4890 4891 bootpretryperiod - Period during which BOOTP/DHCP sends retries. 4892 Unsigned value, in milliseconds. If not set, the period will 4893 be either the default (28000), or a value based on 4894 CONFIG_NET_RETRY_COUNT, if defined. This value has 4895 precedence over the valu based on CONFIG_NET_RETRY_COUNT. 4896 4897The following image location variables contain the location of images 4898used in booting. The "Image" column gives the role of the image and is 4899not an environment variable name. The other columns are environment 4900variable names. "File Name" gives the name of the file on a TFTP 4901server, "RAM Address" gives the location in RAM the image will be 4902loaded to, and "Flash Location" gives the image's address in NOR 4903flash or offset in NAND flash. 4904 4905*Note* - these variables don't have to be defined for all boards, some 4906boards currently use other variables for these purposes, and some 4907boards use these variables for other purposes. 4908 4909Image File Name RAM Address Flash Location 4910----- --------- ----------- -------------- 4911u-boot u-boot u-boot_addr_r u-boot_addr 4912Linux kernel bootfile kernel_addr_r kernel_addr 4913device tree blob fdtfile fdt_addr_r fdt_addr 4914ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 4915 4916The following environment variables may be used and automatically 4917updated by the network boot commands ("bootp" and "rarpboot"), 4918depending the information provided by your boot server: 4919 4920 bootfile - see above 4921 dnsip - IP address of your Domain Name Server 4922 dnsip2 - IP address of your secondary Domain Name Server 4923 gatewayip - IP address of the Gateway (Router) to use 4924 hostname - Target hostname 4925 ipaddr - see above 4926 netmask - Subnet Mask 4927 rootpath - Pathname of the root filesystem on the NFS server 4928 serverip - see above 4929 4930 4931There are two special Environment Variables: 4932 4933 serial# - contains hardware identification information such 4934 as type string and/or serial number 4935 ethaddr - Ethernet address 4936 4937These variables can be set only once (usually during manufacturing of 4938the board). U-Boot refuses to delete or overwrite these variables 4939once they have been set once. 4940 4941 4942Further special Environment Variables: 4943 4944 ver - Contains the U-Boot version string as printed 4945 with the "version" command. This variable is 4946 readonly (see CONFIG_VERSION_VARIABLE). 4947 4948 4949Please note that changes to some configuration parameters may take 4950only effect after the next boot (yes, that's just like Windoze :-). 4951 4952 4953Callback functions for environment variables: 4954--------------------------------------------- 4955 4956For some environment variables, the behavior of u-boot needs to change 4957when their values are changed. This functionality allows functions to 4958be associated with arbitrary variables. On creation, overwrite, or 4959deletion, the callback will provide the opportunity for some side 4960effect to happen or for the change to be rejected. 4961 4962The callbacks are named and associated with a function using the 4963U_BOOT_ENV_CALLBACK macro in your board or driver code. 4964 4965These callbacks are associated with variables in one of two ways. The 4966static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC 4967in the board configuration to a string that defines a list of 4968associations. The list must be in the following format: 4969 4970 entry = variable_name[:callback_name] 4971 list = entry[,list] 4972 4973If the callback name is not specified, then the callback is deleted. 4974Spaces are also allowed anywhere in the list. 4975 4976Callbacks can also be associated by defining the ".callbacks" variable 4977with the same list format above. Any association in ".callbacks" will 4978override any association in the static list. You can define 4979CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the 4980".callbacks" environment variable in the default or embedded environment. 4981 4982If CONFIG_REGEX is defined, the variable_name above is evaluated as a 4983regular expression. This allows multiple variables to be connected to 4984the same callback without explicitly listing them all out. 4985 4986 4987Command Line Parsing: 4988===================== 4989 4990There are two different command line parsers available with U-Boot: 4991the old "simple" one, and the much more powerful "hush" shell: 4992 4993Old, simple command line parser: 4994-------------------------------- 4995 4996- supports environment variables (through setenv / saveenv commands) 4997- several commands on one line, separated by ';' 4998- variable substitution using "... ${name} ..." syntax 4999- special characters ('$', ';') can be escaped by prefixing with '\', 5000 for example: 5001 setenv bootcmd bootm \${address} 5002- You can also escape text by enclosing in single apostrophes, for example: 5003 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 5004 5005Hush shell: 5006----------- 5007 5008- similar to Bourne shell, with control structures like 5009 if...then...else...fi, for...do...done; while...do...done, 5010 until...do...done, ... 5011- supports environment ("global") variables (through setenv / saveenv 5012 commands) and local shell variables (through standard shell syntax 5013 "name=value"); only environment variables can be used with "run" 5014 command 5015 5016General rules: 5017-------------- 5018 5019(1) If a command line (or an environment variable executed by a "run" 5020 command) contains several commands separated by semicolon, and 5021 one of these commands fails, then the remaining commands will be 5022 executed anyway. 5023 5024(2) If you execute several variables with one call to run (i. e. 5025 calling run with a list of variables as arguments), any failing 5026 command will cause "run" to terminate, i. e. the remaining 5027 variables are not executed. 5028 5029Note for Redundant Ethernet Interfaces: 5030======================================= 5031 5032Some boards come with redundant Ethernet interfaces; U-Boot supports 5033such configurations and is capable of automatic selection of a 5034"working" interface when needed. MAC assignment works as follows: 5035 5036Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 5037MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 5038"eth1addr" (=>eth1), "eth2addr", ... 5039 5040If the network interface stores some valid MAC address (for instance 5041in SROM), this is used as default address if there is NO correspon- 5042ding setting in the environment; if the corresponding environment 5043variable is set, this overrides the settings in the card; that means: 5044 5045o If the SROM has a valid MAC address, and there is no address in the 5046 environment, the SROM's address is used. 5047 5048o If there is no valid address in the SROM, and a definition in the 5049 environment exists, then the value from the environment variable is 5050 used. 5051 5052o If both the SROM and the environment contain a MAC address, and 5053 both addresses are the same, this MAC address is used. 5054 5055o If both the SROM and the environment contain a MAC address, and the 5056 addresses differ, the value from the environment is used and a 5057 warning is printed. 5058 5059o If neither SROM nor the environment contain a MAC address, an error 5060 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case 5061 a random, locally-assigned MAC is used. 5062 5063If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 5064will be programmed into hardware as part of the initialization process. This 5065may be skipped by setting the appropriate 'ethmacskip' environment variable. 5066The naming convention is as follows: 5067"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 5068 5069Image Formats: 5070============== 5071 5072U-Boot is capable of booting (and performing other auxiliary operations on) 5073images in two formats: 5074 5075New uImage format (FIT) 5076----------------------- 5077 5078Flexible and powerful format based on Flattened Image Tree -- FIT (similar 5079to Flattened Device Tree). It allows the use of images with multiple 5080components (several kernels, ramdisks, etc.), with contents protected by 5081SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 5082 5083 5084Old uImage format 5085----------------- 5086 5087Old image format is based on binary files which can be basically anything, 5088preceded by a special header; see the definitions in include/image.h for 5089details; basically, the header defines the following image properties: 5090 5091* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 5092 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 5093 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 5094 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 5095 INTEGRITY). 5096* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 5097 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 5098 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 5099* Compression Type (uncompressed, gzip, bzip2) 5100* Load Address 5101* Entry Point 5102* Image Name 5103* Image Timestamp 5104 5105The header is marked by a special Magic Number, and both the header 5106and the data portions of the image are secured against corruption by 5107CRC32 checksums. 5108 5109 5110Linux Support: 5111============== 5112 5113Although U-Boot should support any OS or standalone application 5114easily, the main focus has always been on Linux during the design of 5115U-Boot. 5116 5117U-Boot includes many features that so far have been part of some 5118special "boot loader" code within the Linux kernel. Also, any 5119"initrd" images to be used are no longer part of one big Linux image; 5120instead, kernel and "initrd" are separate images. This implementation 5121serves several purposes: 5122 5123- the same features can be used for other OS or standalone 5124 applications (for instance: using compressed images to reduce the 5125 Flash memory footprint) 5126 5127- it becomes much easier to port new Linux kernel versions because 5128 lots of low-level, hardware dependent stuff are done by U-Boot 5129 5130- the same Linux kernel image can now be used with different "initrd" 5131 images; of course this also means that different kernel images can 5132 be run with the same "initrd". This makes testing easier (you don't 5133 have to build a new "zImage.initrd" Linux image when you just 5134 change a file in your "initrd"). Also, a field-upgrade of the 5135 software is easier now. 5136 5137 5138Linux HOWTO: 5139============ 5140 5141Porting Linux to U-Boot based systems: 5142--------------------------------------- 5143 5144U-Boot cannot save you from doing all the necessary modifications to 5145configure the Linux device drivers for use with your target hardware 5146(no, we don't intend to provide a full virtual machine interface to 5147Linux :-). 5148 5149But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 5150 5151Just make sure your machine specific header file (for instance 5152include/asm-ppc/tqm8xx.h) includes the same definition of the Board 5153Information structure as we define in include/asm-<arch>/u-boot.h, 5154and make sure that your definition of IMAP_ADDR uses the same value 5155as your U-Boot configuration in CONFIG_SYS_IMMR. 5156 5157Note that U-Boot now has a driver model, a unified model for drivers. 5158If you are adding a new driver, plumb it into driver model. If there 5159is no uclass available, you are encouraged to create one. See 5160doc/driver-model. 5161 5162 5163Configuring the Linux kernel: 5164----------------------------- 5165 5166No specific requirements for U-Boot. Make sure you have some root 5167device (initial ramdisk, NFS) for your target system. 5168 5169 5170Building a Linux Image: 5171----------------------- 5172 5173With U-Boot, "normal" build targets like "zImage" or "bzImage" are 5174not used. If you use recent kernel source, a new build target 5175"uImage" will exist which automatically builds an image usable by 5176U-Boot. Most older kernels also have support for a "pImage" target, 5177which was introduced for our predecessor project PPCBoot and uses a 5178100% compatible format. 5179 5180Example: 5181 5182 make TQM850L_defconfig 5183 make oldconfig 5184 make dep 5185 make uImage 5186 5187The "uImage" build target uses a special tool (in 'tools/mkimage') to 5188encapsulate a compressed Linux kernel image with header information, 5189CRC32 checksum etc. for use with U-Boot. This is what we are doing: 5190 5191* build a standard "vmlinux" kernel image (in ELF binary format): 5192 5193* convert the kernel into a raw binary image: 5194 5195 ${CROSS_COMPILE}-objcopy -O binary \ 5196 -R .note -R .comment \ 5197 -S vmlinux linux.bin 5198 5199* compress the binary image: 5200 5201 gzip -9 linux.bin 5202 5203* package compressed binary image for U-Boot: 5204 5205 mkimage -A ppc -O linux -T kernel -C gzip \ 5206 -a 0 -e 0 -n "Linux Kernel Image" \ 5207 -d linux.bin.gz uImage 5208 5209 5210The "mkimage" tool can also be used to create ramdisk images for use 5211with U-Boot, either separated from the Linux kernel image, or 5212combined into one file. "mkimage" encapsulates the images with a 64 5213byte header containing information about target architecture, 5214operating system, image type, compression method, entry points, time 5215stamp, CRC32 checksums, etc. 5216 5217"mkimage" can be called in two ways: to verify existing images and 5218print the header information, or to build new images. 5219 5220In the first form (with "-l" option) mkimage lists the information 5221contained in the header of an existing U-Boot image; this includes 5222checksum verification: 5223 5224 tools/mkimage -l image 5225 -l ==> list image header information 5226 5227The second form (with "-d" option) is used to build a U-Boot image 5228from a "data file" which is used as image payload: 5229 5230 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 5231 -n name -d data_file image 5232 -A ==> set architecture to 'arch' 5233 -O ==> set operating system to 'os' 5234 -T ==> set image type to 'type' 5235 -C ==> set compression type 'comp' 5236 -a ==> set load address to 'addr' (hex) 5237 -e ==> set entry point to 'ep' (hex) 5238 -n ==> set image name to 'name' 5239 -d ==> use image data from 'datafile' 5240 5241Right now, all Linux kernels for PowerPC systems use the same load 5242address (0x00000000), but the entry point address depends on the 5243kernel version: 5244 5245- 2.2.x kernels have the entry point at 0x0000000C, 5246- 2.3.x and later kernels have the entry point at 0x00000000. 5247 5248So a typical call to build a U-Boot image would read: 5249 5250 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5251 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 5252 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 5253 > examples/uImage.TQM850L 5254 Image Name: 2.4.4 kernel for TQM850L 5255 Created: Wed Jul 19 02:34:59 2000 5256 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5257 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5258 Load Address: 0x00000000 5259 Entry Point: 0x00000000 5260 5261To verify the contents of the image (or check for corruption): 5262 5263 -> tools/mkimage -l examples/uImage.TQM850L 5264 Image Name: 2.4.4 kernel for TQM850L 5265 Created: Wed Jul 19 02:34:59 2000 5266 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5267 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5268 Load Address: 0x00000000 5269 Entry Point: 0x00000000 5270 5271NOTE: for embedded systems where boot time is critical you can trade 5272speed for memory and install an UNCOMPRESSED image instead: this 5273needs more space in Flash, but boots much faster since it does not 5274need to be uncompressed: 5275 5276 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 5277 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5278 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 5279 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 5280 > examples/uImage.TQM850L-uncompressed 5281 Image Name: 2.4.4 kernel for TQM850L 5282 Created: Wed Jul 19 02:34:59 2000 5283 Image Type: PowerPC Linux Kernel Image (uncompressed) 5284 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 5285 Load Address: 0x00000000 5286 Entry Point: 0x00000000 5287 5288 5289Similar you can build U-Boot images from a 'ramdisk.image.gz' file 5290when your kernel is intended to use an initial ramdisk: 5291 5292 -> tools/mkimage -n 'Simple Ramdisk Image' \ 5293 > -A ppc -O linux -T ramdisk -C gzip \ 5294 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 5295 Image Name: Simple Ramdisk Image 5296 Created: Wed Jan 12 14:01:50 2000 5297 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5298 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 5299 Load Address: 0x00000000 5300 Entry Point: 0x00000000 5301 5302The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i" 5303option performs the converse operation of the mkimage's second form (the "-d" 5304option). Given an image built by mkimage, the dumpimage extracts a "data file" 5305from the image: 5306 5307 tools/dumpimage -i image -T type -p position data_file 5308 -i ==> extract from the 'image' a specific 'data_file' 5309 -T ==> set image type to 'type' 5310 -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image' 5311 5312 5313Installing a Linux Image: 5314------------------------- 5315 5316To downloading a U-Boot image over the serial (console) interface, 5317you must convert the image to S-Record format: 5318 5319 objcopy -I binary -O srec examples/image examples/image.srec 5320 5321The 'objcopy' does not understand the information in the U-Boot 5322image header, so the resulting S-Record file will be relative to 5323address 0x00000000. To load it to a given address, you need to 5324specify the target address as 'offset' parameter with the 'loads' 5325command. 5326 5327Example: install the image to address 0x40100000 (which on the 5328TQM8xxL is in the first Flash bank): 5329 5330 => erase 40100000 401FFFFF 5331 5332 .......... done 5333 Erased 8 sectors 5334 5335 => loads 40100000 5336 ## Ready for S-Record download ... 5337 ~>examples/image.srec 5338 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 5339 ... 5340 15989 15990 15991 15992 5341 [file transfer complete] 5342 [connected] 5343 ## Start Addr = 0x00000000 5344 5345 5346You can check the success of the download using the 'iminfo' command; 5347this includes a checksum verification so you can be sure no data 5348corruption happened: 5349 5350 => imi 40100000 5351 5352 ## Checking Image at 40100000 ... 5353 Image Name: 2.2.13 for initrd on TQM850L 5354 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5355 Data Size: 335725 Bytes = 327 kB = 0 MB 5356 Load Address: 00000000 5357 Entry Point: 0000000c 5358 Verifying Checksum ... OK 5359 5360 5361Boot Linux: 5362----------- 5363 5364The "bootm" command is used to boot an application that is stored in 5365memory (RAM or Flash). In case of a Linux kernel image, the contents 5366of the "bootargs" environment variable is passed to the kernel as 5367parameters. You can check and modify this variable using the 5368"printenv" and "setenv" commands: 5369 5370 5371 => printenv bootargs 5372 bootargs=root=/dev/ram 5373 5374 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5375 5376 => printenv bootargs 5377 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5378 5379 => bootm 40020000 5380 ## Booting Linux kernel at 40020000 ... 5381 Image Name: 2.2.13 for NFS on TQM850L 5382 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5383 Data Size: 381681 Bytes = 372 kB = 0 MB 5384 Load Address: 00000000 5385 Entry Point: 0000000c 5386 Verifying Checksum ... OK 5387 Uncompressing Kernel Image ... OK 5388 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 5389 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5390 time_init: decrementer frequency = 187500000/60 5391 Calibrating delay loop... 49.77 BogoMIPS 5392 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 5393 ... 5394 5395If you want to boot a Linux kernel with initial RAM disk, you pass 5396the memory addresses of both the kernel and the initrd image (PPBCOOT 5397format!) to the "bootm" command: 5398 5399 => imi 40100000 40200000 5400 5401 ## Checking Image at 40100000 ... 5402 Image Name: 2.2.13 for initrd on TQM850L 5403 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5404 Data Size: 335725 Bytes = 327 kB = 0 MB 5405 Load Address: 00000000 5406 Entry Point: 0000000c 5407 Verifying Checksum ... OK 5408 5409 ## Checking Image at 40200000 ... 5410 Image Name: Simple Ramdisk Image 5411 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5412 Data Size: 566530 Bytes = 553 kB = 0 MB 5413 Load Address: 00000000 5414 Entry Point: 00000000 5415 Verifying Checksum ... OK 5416 5417 => bootm 40100000 40200000 5418 ## Booting Linux kernel at 40100000 ... 5419 Image Name: 2.2.13 for initrd on TQM850L 5420 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5421 Data Size: 335725 Bytes = 327 kB = 0 MB 5422 Load Address: 00000000 5423 Entry Point: 0000000c 5424 Verifying Checksum ... OK 5425 Uncompressing Kernel Image ... OK 5426 ## Loading RAMDisk Image at 40200000 ... 5427 Image Name: Simple Ramdisk Image 5428 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5429 Data Size: 566530 Bytes = 553 kB = 0 MB 5430 Load Address: 00000000 5431 Entry Point: 00000000 5432 Verifying Checksum ... OK 5433 Loading Ramdisk ... OK 5434 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 5435 Boot arguments: root=/dev/ram 5436 time_init: decrementer frequency = 187500000/60 5437 Calibrating delay loop... 49.77 BogoMIPS 5438 ... 5439 RAMDISK: Compressed image found at block 0 5440 VFS: Mounted root (ext2 filesystem). 5441 5442 bash# 5443 5444Boot Linux and pass a flat device tree: 5445----------- 5446 5447First, U-Boot must be compiled with the appropriate defines. See the section 5448titled "Linux Kernel Interface" above for a more in depth explanation. The 5449following is an example of how to start a kernel and pass an updated 5450flat device tree: 5451 5452=> print oftaddr 5453oftaddr=0x300000 5454=> print oft 5455oft=oftrees/mpc8540ads.dtb 5456=> tftp $oftaddr $oft 5457Speed: 1000, full duplex 5458Using TSEC0 device 5459TFTP from server 192.168.1.1; our IP address is 192.168.1.101 5460Filename 'oftrees/mpc8540ads.dtb'. 5461Load address: 0x300000 5462Loading: # 5463done 5464Bytes transferred = 4106 (100a hex) 5465=> tftp $loadaddr $bootfile 5466Speed: 1000, full duplex 5467Using TSEC0 device 5468TFTP from server 192.168.1.1; our IP address is 192.168.1.2 5469Filename 'uImage'. 5470Load address: 0x200000 5471Loading:############ 5472done 5473Bytes transferred = 1029407 (fb51f hex) 5474=> print loadaddr 5475loadaddr=200000 5476=> print oftaddr 5477oftaddr=0x300000 5478=> bootm $loadaddr - $oftaddr 5479## Booting image at 00200000 ... 5480 Image Name: Linux-2.6.17-dirty 5481 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5482 Data Size: 1029343 Bytes = 1005.2 kB 5483 Load Address: 00000000 5484 Entry Point: 00000000 5485 Verifying Checksum ... OK 5486 Uncompressing Kernel Image ... OK 5487Booting using flat device tree at 0x300000 5488Using MPC85xx ADS machine description 5489Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 5490[snip] 5491 5492 5493More About U-Boot Image Types: 5494------------------------------ 5495 5496U-Boot supports the following image types: 5497 5498 "Standalone Programs" are directly runnable in the environment 5499 provided by U-Boot; it is expected that (if they behave 5500 well) you can continue to work in U-Boot after return from 5501 the Standalone Program. 5502 "OS Kernel Images" are usually images of some Embedded OS which 5503 will take over control completely. Usually these programs 5504 will install their own set of exception handlers, device 5505 drivers, set up the MMU, etc. - this means, that you cannot 5506 expect to re-enter U-Boot except by resetting the CPU. 5507 "RAMDisk Images" are more or less just data blocks, and their 5508 parameters (address, size) are passed to an OS kernel that is 5509 being started. 5510 "Multi-File Images" contain several images, typically an OS 5511 (Linux) kernel image and one or more data images like 5512 RAMDisks. This construct is useful for instance when you want 5513 to boot over the network using BOOTP etc., where the boot 5514 server provides just a single image file, but you want to get 5515 for instance an OS kernel and a RAMDisk image. 5516 5517 "Multi-File Images" start with a list of image sizes, each 5518 image size (in bytes) specified by an "uint32_t" in network 5519 byte order. This list is terminated by an "(uint32_t)0". 5520 Immediately after the terminating 0 follow the images, one by 5521 one, all aligned on "uint32_t" boundaries (size rounded up to 5522 a multiple of 4 bytes). 5523 5524 "Firmware Images" are binary images containing firmware (like 5525 U-Boot or FPGA images) which usually will be programmed to 5526 flash memory. 5527 5528 "Script files" are command sequences that will be executed by 5529 U-Boot's command interpreter; this feature is especially 5530 useful when you configure U-Boot to use a real shell (hush) 5531 as command interpreter. 5532 5533Booting the Linux zImage: 5534------------------------- 5535 5536On some platforms, it's possible to boot Linux zImage. This is done 5537using the "bootz" command. The syntax of "bootz" command is the same 5538as the syntax of "bootm" command. 5539 5540Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply 5541kernel with raw initrd images. The syntax is slightly different, the 5542address of the initrd must be augmented by it's size, in the following 5543format: "<initrd addres>:<initrd size>". 5544 5545 5546Standalone HOWTO: 5547================= 5548 5549One of the features of U-Boot is that you can dynamically load and 5550run "standalone" applications, which can use some resources of 5551U-Boot like console I/O functions or interrupt services. 5552 5553Two simple examples are included with the sources: 5554 5555"Hello World" Demo: 5556------------------- 5557 5558'examples/hello_world.c' contains a small "Hello World" Demo 5559application; it is automatically compiled when you build U-Boot. 5560It's configured to run at address 0x00040004, so you can play with it 5561like that: 5562 5563 => loads 5564 ## Ready for S-Record download ... 5565 ~>examples/hello_world.srec 5566 1 2 3 4 5 6 7 8 9 10 11 ... 5567 [file transfer complete] 5568 [connected] 5569 ## Start Addr = 0x00040004 5570 5571 => go 40004 Hello World! This is a test. 5572 ## Starting application at 0x00040004 ... 5573 Hello World 5574 argc = 7 5575 argv[0] = "40004" 5576 argv[1] = "Hello" 5577 argv[2] = "World!" 5578 argv[3] = "This" 5579 argv[4] = "is" 5580 argv[5] = "a" 5581 argv[6] = "test." 5582 argv[7] = "<NULL>" 5583 Hit any key to exit ... 5584 5585 ## Application terminated, rc = 0x0 5586 5587Another example, which demonstrates how to register a CPM interrupt 5588handler with the U-Boot code, can be found in 'examples/timer.c'. 5589Here, a CPM timer is set up to generate an interrupt every second. 5590The interrupt service routine is trivial, just printing a '.' 5591character, but this is just a demo program. The application can be 5592controlled by the following keys: 5593 5594 ? - print current values og the CPM Timer registers 5595 b - enable interrupts and start timer 5596 e - stop timer and disable interrupts 5597 q - quit application 5598 5599 => loads 5600 ## Ready for S-Record download ... 5601 ~>examples/timer.srec 5602 1 2 3 4 5 6 7 8 9 10 11 ... 5603 [file transfer complete] 5604 [connected] 5605 ## Start Addr = 0x00040004 5606 5607 => go 40004 5608 ## Starting application at 0x00040004 ... 5609 TIMERS=0xfff00980 5610 Using timer 1 5611 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 5612 5613Hit 'b': 5614 [q, b, e, ?] Set interval 1000000 us 5615 Enabling timer 5616Hit '?': 5617 [q, b, e, ?] ........ 5618 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 5619Hit '?': 5620 [q, b, e, ?] . 5621 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 5622Hit '?': 5623 [q, b, e, ?] . 5624 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 5625Hit '?': 5626 [q, b, e, ?] . 5627 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 5628Hit 'e': 5629 [q, b, e, ?] ...Stopping timer 5630Hit 'q': 5631 [q, b, e, ?] ## Application terminated, rc = 0x0 5632 5633 5634Minicom warning: 5635================ 5636 5637Over time, many people have reported problems when trying to use the 5638"minicom" terminal emulation program for serial download. I (wd) 5639consider minicom to be broken, and recommend not to use it. Under 5640Unix, I recommend to use C-Kermit for general purpose use (and 5641especially for kermit binary protocol download ("loadb" command), and 5642use "cu" for S-Record download ("loads" command). See 5643http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3. 5644for help with kermit. 5645 5646 5647Nevertheless, if you absolutely want to use it try adding this 5648configuration to your "File transfer protocols" section: 5649 5650 Name Program Name U/D FullScr IO-Red. Multi 5651 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 5652 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 5653 5654 5655NetBSD Notes: 5656============= 5657 5658Starting at version 0.9.2, U-Boot supports NetBSD both as host 5659(build U-Boot) and target system (boots NetBSD/mpc8xx). 5660 5661Building requires a cross environment; it is known to work on 5662NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 5663need gmake since the Makefiles are not compatible with BSD make). 5664Note that the cross-powerpc package does not install include files; 5665attempting to build U-Boot will fail because <machine/ansi.h> is 5666missing. This file has to be installed and patched manually: 5667 5668 # cd /usr/pkg/cross/powerpc-netbsd/include 5669 # mkdir powerpc 5670 # ln -s powerpc machine 5671 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 5672 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 5673 5674Native builds *don't* work due to incompatibilities between native 5675and U-Boot include files. 5676 5677Booting assumes that (the first part of) the image booted is a 5678stage-2 loader which in turn loads and then invokes the kernel 5679proper. Loader sources will eventually appear in the NetBSD source 5680tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 5681meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 5682 5683 5684Implementation Internals: 5685========================= 5686 5687The following is not intended to be a complete description of every 5688implementation detail. However, it should help to understand the 5689inner workings of U-Boot and make it easier to port it to custom 5690hardware. 5691 5692 5693Initial Stack, Global Data: 5694--------------------------- 5695 5696The implementation of U-Boot is complicated by the fact that U-Boot 5697starts running out of ROM (flash memory), usually without access to 5698system RAM (because the memory controller is not initialized yet). 5699This means that we don't have writable Data or BSS segments, and BSS 5700is not initialized as zero. To be able to get a C environment working 5701at all, we have to allocate at least a minimal stack. Implementation 5702options for this are defined and restricted by the CPU used: Some CPU 5703models provide on-chip memory (like the IMMR area on MPC8xx and 5704MPC826x processors), on others (parts of) the data cache can be 5705locked as (mis-) used as memory, etc. 5706 5707 Chris Hallinan posted a good summary of these issues to the 5708 U-Boot mailing list: 5709 5710 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 5711 From: "Chris Hallinan" <clh@net1plus.com> 5712 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 5713 ... 5714 5715 Correct me if I'm wrong, folks, but the way I understand it 5716 is this: Using DCACHE as initial RAM for Stack, etc, does not 5717 require any physical RAM backing up the cache. The cleverness 5718 is that the cache is being used as a temporary supply of 5719 necessary storage before the SDRAM controller is setup. It's 5720 beyond the scope of this list to explain the details, but you 5721 can see how this works by studying the cache architecture and 5722 operation in the architecture and processor-specific manuals. 5723 5724 OCM is On Chip Memory, which I believe the 405GP has 4K. It 5725 is another option for the system designer to use as an 5726 initial stack/RAM area prior to SDRAM being available. Either 5727 option should work for you. Using CS 4 should be fine if your 5728 board designers haven't used it for something that would 5729 cause you grief during the initial boot! It is frequently not 5730 used. 5731 5732 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 5733 with your processor/board/system design. The default value 5734 you will find in any recent u-boot distribution in 5735 walnut.h should work for you. I'd set it to a value larger 5736 than your SDRAM module. If you have a 64MB SDRAM module, set 5737 it above 400_0000. Just make sure your board has no resources 5738 that are supposed to respond to that address! That code in 5739 start.S has been around a while and should work as is when 5740 you get the config right. 5741 5742 -Chris Hallinan 5743 DS4.COM, Inc. 5744 5745It is essential to remember this, since it has some impact on the C 5746code for the initialization procedures: 5747 5748* Initialized global data (data segment) is read-only. Do not attempt 5749 to write it. 5750 5751* Do not use any uninitialized global data (or implicitly initialized 5752 as zero data - BSS segment) at all - this is undefined, initiali- 5753 zation is performed later (when relocating to RAM). 5754 5755* Stack space is very limited. Avoid big data buffers or things like 5756 that. 5757 5758Having only the stack as writable memory limits means we cannot use 5759normal global data to share information between the code. But it 5760turned out that the implementation of U-Boot can be greatly 5761simplified by making a global data structure (gd_t) available to all 5762functions. We could pass a pointer to this data as argument to _all_ 5763functions, but this would bloat the code. Instead we use a feature of 5764the GCC compiler (Global Register Variables) to share the data: we 5765place a pointer (gd) to the global data into a register which we 5766reserve for this purpose. 5767 5768When choosing a register for such a purpose we are restricted by the 5769relevant (E)ABI specifications for the current architecture, and by 5770GCC's implementation. 5771 5772For PowerPC, the following registers have specific use: 5773 R1: stack pointer 5774 R2: reserved for system use 5775 R3-R4: parameter passing and return values 5776 R5-R10: parameter passing 5777 R13: small data area pointer 5778 R30: GOT pointer 5779 R31: frame pointer 5780 5781 (U-Boot also uses R12 as internal GOT pointer. r12 5782 is a volatile register so r12 needs to be reset when 5783 going back and forth between asm and C) 5784 5785 ==> U-Boot will use R2 to hold a pointer to the global data 5786 5787 Note: on PPC, we could use a static initializer (since the 5788 address of the global data structure is known at compile time), 5789 but it turned out that reserving a register results in somewhat 5790 smaller code - although the code savings are not that big (on 5791 average for all boards 752 bytes for the whole U-Boot image, 5792 624 text + 127 data). 5793 5794On ARM, the following registers are used: 5795 5796 R0: function argument word/integer result 5797 R1-R3: function argument word 5798 R9: platform specific 5799 R10: stack limit (used only if stack checking is enabled) 5800 R11: argument (frame) pointer 5801 R12: temporary workspace 5802 R13: stack pointer 5803 R14: link register 5804 R15: program counter 5805 5806 ==> U-Boot will use R9 to hold a pointer to the global data 5807 5808 Note: on ARM, only R_ARM_RELATIVE relocations are supported. 5809 5810On Nios II, the ABI is documented here: 5811 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 5812 5813 ==> U-Boot will use gp to hold a pointer to the global data 5814 5815 Note: on Nios II, we give "-G0" option to gcc and don't use gp 5816 to access small data sections, so gp is free. 5817 5818On NDS32, the following registers are used: 5819 5820 R0-R1: argument/return 5821 R2-R5: argument 5822 R15: temporary register for assembler 5823 R16: trampoline register 5824 R28: frame pointer (FP) 5825 R29: global pointer (GP) 5826 R30: link register (LP) 5827 R31: stack pointer (SP) 5828 PC: program counter (PC) 5829 5830 ==> U-Boot will use R10 to hold a pointer to the global data 5831 5832NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 5833or current versions of GCC may "optimize" the code too much. 5834 5835Memory Management: 5836------------------ 5837 5838U-Boot runs in system state and uses physical addresses, i.e. the 5839MMU is not used either for address mapping nor for memory protection. 5840 5841The available memory is mapped to fixed addresses using the memory 5842controller. In this process, a contiguous block is formed for each 5843memory type (Flash, SDRAM, SRAM), even when it consists of several 5844physical memory banks. 5845 5846U-Boot is installed in the first 128 kB of the first Flash bank (on 5847TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 5848booting and sizing and initializing DRAM, the code relocates itself 5849to the upper end of DRAM. Immediately below the U-Boot code some 5850memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 5851configuration setting]. Below that, a structure with global Board 5852Info data is placed, followed by the stack (growing downward). 5853 5854Additionally, some exception handler code is copied to the low 8 kB 5855of DRAM (0x00000000 ... 0x00001FFF). 5856 5857So a typical memory configuration with 16 MB of DRAM could look like 5858this: 5859 5860 0x0000 0000 Exception Vector code 5861 : 5862 0x0000 1FFF 5863 0x0000 2000 Free for Application Use 5864 : 5865 : 5866 5867 : 5868 : 5869 0x00FB FF20 Monitor Stack (Growing downward) 5870 0x00FB FFAC Board Info Data and permanent copy of global data 5871 0x00FC 0000 Malloc Arena 5872 : 5873 0x00FD FFFF 5874 0x00FE 0000 RAM Copy of Monitor Code 5875 ... eventually: LCD or video framebuffer 5876 ... eventually: pRAM (Protected RAM - unchanged by reset) 5877 0x00FF FFFF [End of RAM] 5878 5879 5880System Initialization: 5881---------------------- 5882 5883In the reset configuration, U-Boot starts at the reset entry point 5884(on most PowerPC systems at address 0x00000100). Because of the reset 5885configuration for CS0# this is a mirror of the on board Flash memory. 5886To be able to re-map memory U-Boot then jumps to its link address. 5887To be able to implement the initialization code in C, a (small!) 5888initial stack is set up in the internal Dual Ported RAM (in case CPUs 5889which provide such a feature like MPC8xx or MPC8260), or in a locked 5890part of the data cache. After that, U-Boot initializes the CPU core, 5891the caches and the SIU. 5892 5893Next, all (potentially) available memory banks are mapped using a 5894preliminary mapping. For example, we put them on 512 MB boundaries 5895(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 5896on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 5897programmed for SDRAM access. Using the temporary configuration, a 5898simple memory test is run that determines the size of the SDRAM 5899banks. 5900 5901When there is more than one SDRAM bank, and the banks are of 5902different size, the largest is mapped first. For equal size, the first 5903bank (CS2#) is mapped first. The first mapping is always for address 59040x00000000, with any additional banks following immediately to create 5905contiguous memory starting from 0. 5906 5907Then, the monitor installs itself at the upper end of the SDRAM area 5908and allocates memory for use by malloc() and for the global Board 5909Info data; also, the exception vector code is copied to the low RAM 5910pages, and the final stack is set up. 5911 5912Only after this relocation will you have a "normal" C environment; 5913until that you are restricted in several ways, mostly because you are 5914running from ROM, and because the code will have to be relocated to a 5915new address in RAM. 5916 5917 5918U-Boot Porting Guide: 5919---------------------- 5920 5921[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 5922list, October 2002] 5923 5924 5925int main(int argc, char *argv[]) 5926{ 5927 sighandler_t no_more_time; 5928 5929 signal(SIGALRM, no_more_time); 5930 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 5931 5932 if (available_money > available_manpower) { 5933 Pay consultant to port U-Boot; 5934 return 0; 5935 } 5936 5937 Download latest U-Boot source; 5938 5939 Subscribe to u-boot mailing list; 5940 5941 if (clueless) 5942 email("Hi, I am new to U-Boot, how do I get started?"); 5943 5944 while (learning) { 5945 Read the README file in the top level directory; 5946 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 5947 Read applicable doc/*.README; 5948 Read the source, Luke; 5949 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 5950 } 5951 5952 if (available_money > toLocalCurrency ($2500)) 5953 Buy a BDI3000; 5954 else 5955 Add a lot of aggravation and time; 5956 5957 if (a similar board exists) { /* hopefully... */ 5958 cp -a board/<similar> board/<myboard> 5959 cp include/configs/<similar>.h include/configs/<myboard>.h 5960 } else { 5961 Create your own board support subdirectory; 5962 Create your own board include/configs/<myboard>.h file; 5963 } 5964 Edit new board/<myboard> files 5965 Edit new include/configs/<myboard>.h 5966 5967 while (!accepted) { 5968 while (!running) { 5969 do { 5970 Add / modify source code; 5971 } until (compiles); 5972 Debug; 5973 if (clueless) 5974 email("Hi, I am having problems..."); 5975 } 5976 Send patch file to the U-Boot email list; 5977 if (reasonable critiques) 5978 Incorporate improvements from email list code review; 5979 else 5980 Defend code as written; 5981 } 5982 5983 return 0; 5984} 5985 5986void no_more_time (int sig) 5987{ 5988 hire_a_guru(); 5989} 5990 5991 5992Coding Standards: 5993----------------- 5994 5995All contributions to U-Boot should conform to the Linux kernel 5996coding style; see the file "Documentation/CodingStyle" and the script 5997"scripts/Lindent" in your Linux kernel source directory. 5998 5999Source files originating from a different project (for example the 6000MTD subsystem) are generally exempt from these guidelines and are not 6001reformatted to ease subsequent migration to newer versions of those 6002sources. 6003 6004Please note that U-Boot is implemented in C (and to some small parts in 6005Assembler); no C++ is used, so please do not use C++ style comments (//) 6006in your code. 6007 6008Please also stick to the following formatting rules: 6009- remove any trailing white space 6010- use TAB characters for indentation and vertical alignment, not spaces 6011- make sure NOT to use DOS '\r\n' line feeds 6012- do not add more than 2 consecutive empty lines to source files 6013- do not add trailing empty lines to source files 6014 6015Submissions which do not conform to the standards may be returned 6016with a request to reformat the changes. 6017 6018 6019Submitting Patches: 6020------------------- 6021 6022Since the number of patches for U-Boot is growing, we need to 6023establish some rules. Submissions which do not conform to these rules 6024may be rejected, even when they contain important and valuable stuff. 6025 6026Please see http://www.denx.de/wiki/U-Boot/Patches for details. 6027 6028Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 6029see http://lists.denx.de/mailman/listinfo/u-boot 6030 6031When you send a patch, please include the following information with 6032it: 6033 6034* For bug fixes: a description of the bug and how your patch fixes 6035 this bug. Please try to include a way of demonstrating that the 6036 patch actually fixes something. 6037 6038* For new features: a description of the feature and your 6039 implementation. 6040 6041* A CHANGELOG entry as plaintext (separate from the patch) 6042 6043* For major contributions, add a MAINTAINERS file with your 6044 information and associated file and directory references. 6045 6046* When you add support for a new board, don't forget to add a 6047 maintainer e-mail address to the boards.cfg file, too. 6048 6049* If your patch adds new configuration options, don't forget to 6050 document these in the README file. 6051 6052* The patch itself. If you are using git (which is *strongly* 6053 recommended) you can easily generate the patch using the 6054 "git format-patch". If you then use "git send-email" to send it to 6055 the U-Boot mailing list, you will avoid most of the common problems 6056 with some other mail clients. 6057 6058 If you cannot use git, use "diff -purN OLD NEW". If your version of 6059 diff does not support these options, then get the latest version of 6060 GNU diff. 6061 6062 The current directory when running this command shall be the parent 6063 directory of the U-Boot source tree (i. e. please make sure that 6064 your patch includes sufficient directory information for the 6065 affected files). 6066 6067 We prefer patches as plain text. MIME attachments are discouraged, 6068 and compressed attachments must not be used. 6069 6070* If one logical set of modifications affects or creates several 6071 files, all these changes shall be submitted in a SINGLE patch file. 6072 6073* Changesets that contain different, unrelated modifications shall be 6074 submitted as SEPARATE patches, one patch per changeset. 6075 6076 6077Notes: 6078 6079* Before sending the patch, run the buildman script on your patched 6080 source tree and make sure that no errors or warnings are reported 6081 for any of the boards. 6082 6083* Keep your modifications to the necessary minimum: A patch 6084 containing several unrelated changes or arbitrary reformats will be 6085 returned with a request to re-formatting / split it. 6086 6087* If you modify existing code, make sure that your new code does not 6088 add to the memory footprint of the code ;-) Small is beautiful! 6089 When adding new features, these should compile conditionally only 6090 (using #ifdef), and the resulting code with the new feature 6091 disabled must not need more memory than the old code without your 6092 modification. 6093 6094* Remember that there is a size limit of 100 kB per message on the 6095 u-boot mailing list. Bigger patches will be moderated. If they are 6096 reasonable and not too big, they will be acknowledged. But patches 6097 bigger than the size limit should be avoided. 6098