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 /blackfin Files generic to Analog Devices Blackfin architecture 141 /m68k Files generic to m68k architecture 142 /microblaze Files generic to microblaze architecture 143 /mips Files generic to MIPS architecture 144 /nds32 Files generic to NDS32 architecture 145 /nios2 Files generic to Altera NIOS2 architecture 146 /openrisc Files generic to OpenRISC architecture 147 /powerpc Files generic to PowerPC architecture 148 /sandbox Files generic to HW-independent "sandbox" 149 /sh Files generic to SH architecture 150 /sparc Files generic to SPARC architecture 151 /x86 Files generic to x86 architecture 152/api Machine/arch independent API for external apps 153/board Board dependent files 154/cmd U-Boot commands functions 155/common Misc architecture independent functions 156/configs Board default configuration files 157/disk Code for disk drive partition handling 158/doc Documentation (don't expect too much) 159/drivers Commonly used device drivers 160/dts Contains Makefile for building internal U-Boot fdt. 161/examples Example code for standalone applications, etc. 162/fs Filesystem code (cramfs, ext2, jffs2, etc.) 163/include Header Files 164/lib Library routines generic to all architectures 165/Licenses Various license files 166/net Networking code 167/post Power On Self Test 168/scripts Various build scripts and Makefiles 169/test Various unit test files 170/tools Tools to build S-Record or U-Boot images, etc. 171 172Software Configuration: 173======================= 174 175Configuration is usually done using C preprocessor defines; the 176rationale behind that is to avoid dead code whenever possible. 177 178There are two classes of configuration variables: 179 180* Configuration _OPTIONS_: 181 These are selectable by the user and have names beginning with 182 "CONFIG_". 183 184* Configuration _SETTINGS_: 185 These depend on the hardware etc. and should not be meddled with if 186 you don't know what you're doing; they have names beginning with 187 "CONFIG_SYS_". 188 189Previously, all configuration was done by hand, which involved creating 190symbolic links and editing configuration files manually. More recently, 191U-Boot has added the Kbuild infrastructure used by the Linux kernel, 192allowing you to use the "make menuconfig" command to configure your 193build. 194 195 196Selection of Processor Architecture and Board Type: 197--------------------------------------------------- 198 199For all supported boards there are ready-to-use default 200configurations available; just type "make <board_name>_defconfig". 201 202Example: For a TQM823L module type: 203 204 cd u-boot 205 make TQM823L_defconfig 206 207Note: If you're looking for the default configuration file for a board 208you're sure used to be there but is now missing, check the file 209doc/README.scrapyard for a list of no longer supported boards. 210 211Sandbox Environment: 212-------------------- 213 214U-Boot can be built natively to run on a Linux host using the 'sandbox' 215board. This allows feature development which is not board- or architecture- 216specific to be undertaken on a native platform. The sandbox is also used to 217run some of U-Boot's tests. 218 219See board/sandbox/README.sandbox for more details. 220 221 222Board Initialisation Flow: 223-------------------------- 224 225This is the intended start-up flow for boards. This should apply for both 226SPL and U-Boot proper (i.e. they both follow the same rules). 227 228Note: "SPL" stands for "Secondary Program Loader," which is explained in 229more detail later in this file. 230 231At present, SPL mostly uses a separate code path, but the function names 232and roles of each function are the same. Some boards or architectures 233may not conform to this. At least most ARM boards which use 234CONFIG_SPL_FRAMEWORK conform to this. 235 236Execution typically starts with an architecture-specific (and possibly 237CPU-specific) start.S file, such as: 238 239 - arch/arm/cpu/armv7/start.S 240 - arch/powerpc/cpu/mpc83xx/start.S 241 - arch/mips/cpu/start.S 242 243and so on. From there, three functions are called; the purpose and 244limitations of each of these functions are described below. 245 246lowlevel_init(): 247 - purpose: essential init to permit execution to reach board_init_f() 248 - no global_data or BSS 249 - there is no stack (ARMv7 may have one but it will soon be removed) 250 - must not set up SDRAM or use console 251 - must only do the bare minimum to allow execution to continue to 252 board_init_f() 253 - this is almost never needed 254 - return normally from this function 255 256board_init_f(): 257 - purpose: set up the machine ready for running board_init_r(): 258 i.e. SDRAM and serial UART 259 - global_data is available 260 - stack is in SRAM 261 - BSS is not available, so you cannot use global/static variables, 262 only stack variables and global_data 263 264 Non-SPL-specific notes: 265 - dram_init() is called to set up DRAM. If already done in SPL this 266 can do nothing 267 268 SPL-specific notes: 269 - you can override the entire board_init_f() function with your own 270 version as needed. 271 - preloader_console_init() can be called here in extremis 272 - should set up SDRAM, and anything needed to make the UART work 273 - these is no need to clear BSS, it will be done by crt0.S 274 - must return normally from this function (don't call board_init_r() 275 directly) 276 277Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at 278this point the stack and global_data are relocated to below 279CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of 280memory. 281 282board_init_r(): 283 - purpose: main execution, common code 284 - global_data is available 285 - SDRAM is available 286 - BSS is available, all static/global variables can be used 287 - execution eventually continues to main_loop() 288 289 Non-SPL-specific notes: 290 - U-Boot is relocated to the top of memory and is now running from 291 there. 292 293 SPL-specific notes: 294 - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and 295 CONFIG_SPL_STACK_R_ADDR points into SDRAM 296 - preloader_console_init() can be called here - typically this is 297 done by defining CONFIG_SPL_BOARD_INIT and then supplying a 298 spl_board_init() function containing this call 299 - loads U-Boot or (in falcon mode) Linux 300 301 302 303Configuration Options: 304---------------------- 305 306Configuration depends on the combination of board and CPU type; all 307such information is kept in a configuration file 308"include/configs/<board_name>.h". 309 310Example: For a TQM823L module, all configuration settings are in 311"include/configs/TQM823L.h". 312 313 314Many of the options are named exactly as the corresponding Linux 315kernel configuration options. The intention is to make it easier to 316build a config tool - later. 317 318 319The following options need to be configured: 320 321- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 322 323- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 324 325- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 326 Define exactly one, e.g. CONFIG_ATSTK1002 327 328- Marvell Family Member 329 CONFIG_SYS_MVFS - define it if you want to enable 330 multiple fs option at one time 331 for marvell soc family 332 333- 8xx CPU Options: (if using an MPC8xx CPU) 334 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 335 get_gclk_freq() cannot work 336 e.g. if there is no 32KHz 337 reference PIT/RTC clock 338 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 339 or XTAL/EXTAL) 340 341- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 342 CONFIG_SYS_8xx_CPUCLK_MIN 343 CONFIG_SYS_8xx_CPUCLK_MAX 344 CONFIG_8xx_CPUCLK_DEFAULT 345 See doc/README.MPC866 346 347 CONFIG_SYS_MEASURE_CPUCLK 348 349 Define this to measure the actual CPU clock instead 350 of relying on the correctness of the configured 351 values. Mostly useful for board bringup to make sure 352 the PLL is locked at the intended frequency. Note 353 that this requires a (stable) reference clock (32 kHz 354 RTC clock or CONFIG_SYS_8XX_XIN) 355 356 CONFIG_SYS_DELAYED_ICACHE 357 358 Define this option if you want to enable the 359 ICache only when Code runs from RAM. 360 361- 85xx CPU Options: 362 CONFIG_SYS_PPC64 363 364 Specifies that the core is a 64-bit PowerPC implementation (implements 365 the "64" category of the Power ISA). This is necessary for ePAPR 366 compliance, among other possible reasons. 367 368 CONFIG_SYS_FSL_TBCLK_DIV 369 370 Defines the core time base clock divider ratio compared to the 371 system clock. On most PQ3 devices this is 8, on newer QorIQ 372 devices it can be 16 or 32. The ratio varies from SoC to Soc. 373 374 CONFIG_SYS_FSL_PCIE_COMPAT 375 376 Defines the string to utilize when trying to match PCIe device 377 tree nodes for the given platform. 378 379 CONFIG_SYS_FSL_ERRATUM_A004510 380 381 Enables a workaround for erratum A004510. If set, 382 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and 383 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set. 384 385 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV 386 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional) 387 388 Defines one or two SoC revisions (low 8 bits of SVR) 389 for which the A004510 workaround should be applied. 390 391 The rest of SVR is either not relevant to the decision 392 of whether the erratum is present (e.g. p2040 versus 393 p2041) or is implied by the build target, which controls 394 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set. 395 396 See Freescale App Note 4493 for more information about 397 this erratum. 398 399 CONFIG_A003399_NOR_WORKAROUND 400 Enables a workaround for IFC erratum A003399. It is only 401 required during NOR boot. 402 403 CONFIG_A008044_WORKAROUND 404 Enables a workaround for T1040/T1042 erratum A008044. It is only 405 required during NAND boot and valid for Rev 1.0 SoC revision 406 407 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 408 409 This is the value to write into CCSR offset 0x18600 410 according to the A004510 workaround. 411 412 CONFIG_SYS_FSL_DSP_DDR_ADDR 413 This value denotes start offset of DDR memory which is 414 connected exclusively to the DSP cores. 415 416 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR 417 This value denotes start offset of M2 memory 418 which is directly connected to the DSP core. 419 420 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR 421 This value denotes start offset of M3 memory which is directly 422 connected to the DSP core. 423 424 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT 425 This value denotes start offset of DSP CCSR space. 426 427 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK 428 Single Source Clock is clocking mode present in some of FSL SoC's. 429 In this mode, a single differential clock is used to supply 430 clocks to the sysclock, ddrclock and usbclock. 431 432 CONFIG_SYS_CPC_REINIT_F 433 This CONFIG is defined when the CPC is configured as SRAM at the 434 time of U-Boot entry and is required to be re-initialized. 435 436 CONFIG_DEEP_SLEEP 437 Indicates this SoC supports deep sleep feature. If deep sleep is 438 supported, core will start to execute uboot when wakes up. 439 440- Generic CPU options: 441 CONFIG_SYS_GENERIC_GLOBAL_DATA 442 Defines global data is initialized in generic board board_init_f(). 443 If this macro is defined, global data is created and cleared in 444 generic board board_init_f(). Without this macro, architecture/board 445 should initialize global data before calling board_init_f(). 446 447 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN 448 449 Defines the endianess of the CPU. Implementation of those 450 values is arch specific. 451 452 CONFIG_SYS_FSL_DDR 453 Freescale DDR driver in use. This type of DDR controller is 454 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core 455 SoCs. 456 457 CONFIG_SYS_FSL_DDR_ADDR 458 Freescale DDR memory-mapped register base. 459 460 CONFIG_SYS_FSL_DDR_EMU 461 Specify emulator support for DDR. Some DDR features such as 462 deskew training are not available. 463 464 CONFIG_SYS_FSL_DDRC_GEN1 465 Freescale DDR1 controller. 466 467 CONFIG_SYS_FSL_DDRC_GEN2 468 Freescale DDR2 controller. 469 470 CONFIG_SYS_FSL_DDRC_GEN3 471 Freescale DDR3 controller. 472 473 CONFIG_SYS_FSL_DDRC_GEN4 474 Freescale DDR4 controller. 475 476 CONFIG_SYS_FSL_DDRC_ARM_GEN3 477 Freescale DDR3 controller for ARM-based SoCs. 478 479 CONFIG_SYS_FSL_DDR1 480 Board config to use DDR1. It can be enabled for SoCs with 481 Freescale DDR1 or DDR2 controllers, depending on the board 482 implemetation. 483 484 CONFIG_SYS_FSL_DDR2 485 Board config to use DDR2. It can be enabled for SoCs with 486 Freescale DDR2 or DDR3 controllers, depending on the board 487 implementation. 488 489 CONFIG_SYS_FSL_DDR3 490 Board config to use DDR3. It can be enabled for SoCs with 491 Freescale DDR3 or DDR3L controllers. 492 493 CONFIG_SYS_FSL_DDR3L 494 Board config to use DDR3L. It can be enabled for SoCs with 495 DDR3L controllers. 496 497 CONFIG_SYS_FSL_DDR4 498 Board config to use DDR4. It can be enabled for SoCs with 499 DDR4 controllers. 500 501 CONFIG_SYS_FSL_IFC_BE 502 Defines the IFC controller register space as Big Endian 503 504 CONFIG_SYS_FSL_IFC_LE 505 Defines the IFC controller register space as Little Endian 506 507 CONFIG_SYS_FSL_IFC_CLK_DIV 508 Defines divider of platform clock(clock input to IFC controller). 509 510 CONFIG_SYS_FSL_LBC_CLK_DIV 511 Defines divider of platform clock(clock input to eLBC controller). 512 513 CONFIG_SYS_FSL_PBL_PBI 514 It enables addition of RCW (Power on reset configuration) in built image. 515 Please refer doc/README.pblimage for more details 516 517 CONFIG_SYS_FSL_PBL_RCW 518 It adds PBI(pre-boot instructions) commands in u-boot build image. 519 PBI commands can be used to configure SoC before it starts the execution. 520 Please refer doc/README.pblimage for more details 521 522 CONFIG_SPL_FSL_PBL 523 It adds a target to create boot binary having SPL binary in PBI format 524 concatenated with u-boot binary. 525 526 CONFIG_SYS_FSL_DDR_BE 527 Defines the DDR controller register space as Big Endian 528 529 CONFIG_SYS_FSL_DDR_LE 530 Defines the DDR controller register space as Little Endian 531 532 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY 533 Physical address from the view of DDR controllers. It is the 534 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But 535 it could be different for ARM SoCs. 536 537 CONFIG_SYS_FSL_DDR_INTLV_256B 538 DDR controller interleaving on 256-byte. This is a special 539 interleaving mode, handled by Dickens for Freescale layerscape 540 SoCs with ARM core. 541 542 CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS 543 Number of controllers used as main memory. 544 545 CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS 546 Number of controllers used for other than main memory. 547 548 CONFIG_SYS_FSL_HAS_DP_DDR 549 Defines the SoC has DP-DDR used for DPAA. 550 551 CONFIG_SYS_FSL_SEC_BE 552 Defines the SEC controller register space as Big Endian 553 554 CONFIG_SYS_FSL_SEC_LE 555 Defines the SEC controller register space as Little Endian 556 557- MIPS CPU options: 558 CONFIG_SYS_INIT_SP_OFFSET 559 560 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack 561 pointer. This is needed for the temporary stack before 562 relocation. 563 564 CONFIG_SYS_MIPS_CACHE_MODE 565 566 Cache operation mode for the MIPS CPU. 567 See also arch/mips/include/asm/mipsregs.h. 568 Possible values are: 569 CONF_CM_CACHABLE_NO_WA 570 CONF_CM_CACHABLE_WA 571 CONF_CM_UNCACHED 572 CONF_CM_CACHABLE_NONCOHERENT 573 CONF_CM_CACHABLE_CE 574 CONF_CM_CACHABLE_COW 575 CONF_CM_CACHABLE_CUW 576 CONF_CM_CACHABLE_ACCELERATED 577 578 CONFIG_SYS_XWAY_EBU_BOOTCFG 579 580 Special option for Lantiq XWAY SoCs for booting from NOR flash. 581 See also arch/mips/cpu/mips32/start.S. 582 583 CONFIG_XWAY_SWAP_BYTES 584 585 Enable compilation of tools/xway-swap-bytes needed for Lantiq 586 XWAY SoCs for booting from NOR flash. The U-Boot image needs to 587 be swapped if a flash programmer is used. 588 589- ARM options: 590 CONFIG_SYS_EXCEPTION_VECTORS_HIGH 591 592 Select high exception vectors of the ARM core, e.g., do not 593 clear the V bit of the c1 register of CP15. 594 595 CONFIG_SYS_THUMB_BUILD 596 597 Use this flag to build U-Boot using the Thumb instruction 598 set for ARM architectures. Thumb instruction set provides 599 better code density. For ARM architectures that support 600 Thumb2 this flag will result in Thumb2 code generated by 601 GCC. 602 603 COUNTER_FREQUENCY 604 Generic timer clock source frequency. 605 606 COUNTER_FREQUENCY_REAL 607 Generic timer clock source frequency if the real clock is 608 different from COUNTER_FREQUENCY, and can only be determined 609 at run time. 610 611- Tegra SoC options: 612 CONFIG_TEGRA_SUPPORT_NON_SECURE 613 614 Support executing U-Boot in non-secure (NS) mode. Certain 615 impossible actions will be skipped if the CPU is in NS mode, 616 such as ARM architectural timer initialization. 617 618- Linux Kernel Interface: 619 CONFIG_CLOCKS_IN_MHZ 620 621 U-Boot stores all clock information in Hz 622 internally. For binary compatibility with older Linux 623 kernels (which expect the clocks passed in the 624 bd_info data to be in MHz) the environment variable 625 "clocks_in_mhz" can be defined so that U-Boot 626 converts clock data to MHZ before passing it to the 627 Linux kernel. 628 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 629 "clocks_in_mhz=1" is automatically included in the 630 default environment. 631 632 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 633 634 When transferring memsize parameter to Linux, some versions 635 expect it to be in bytes, others in MB. 636 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 637 638 CONFIG_OF_LIBFDT 639 640 New kernel versions are expecting firmware settings to be 641 passed using flattened device trees (based on open firmware 642 concepts). 643 644 CONFIG_OF_LIBFDT 645 * New libfdt-based support 646 * Adds the "fdt" command 647 * The bootm command automatically updates the fdt 648 649 OF_CPU - The proper name of the cpus node (only required for 650 MPC512X and MPC5xxx based boards). 651 OF_SOC - The proper name of the soc node (only required for 652 MPC512X and MPC5xxx based boards). 653 OF_TBCLK - The timebase frequency. 654 OF_STDOUT_PATH - The path to the console device 655 656 boards with QUICC Engines require OF_QE to set UCC MAC 657 addresses 658 659 CONFIG_OF_BOARD_SETUP 660 661 Board code has addition modification that it wants to make 662 to the flat device tree before handing it off to the kernel 663 664 CONFIG_OF_SYSTEM_SETUP 665 666 Other code has addition modification that it wants to make 667 to the flat device tree before handing it off to the kernel. 668 This causes ft_system_setup() to be called before booting 669 the kernel. 670 671 CONFIG_OF_IDE_FIXUP 672 673 U-Boot can detect if an IDE device is present or not. 674 If not, and this new config option is activated, U-Boot 675 removes the ATA node from the DTS before booting Linux, 676 so the Linux IDE driver does not probe the device and 677 crash. This is needed for buggy hardware (uc101) where 678 no pull down resistor is connected to the signal IDE5V_DD7. 679 680 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 681 682 This setting is mandatory for all boards that have only one 683 machine type and must be used to specify the machine type 684 number as it appears in the ARM machine registry 685 (see http://www.arm.linux.org.uk/developer/machines/). 686 Only boards that have multiple machine types supported 687 in a single configuration file and the machine type is 688 runtime discoverable, do not have to use this setting. 689 690- vxWorks boot parameters: 691 692 bootvx constructs a valid bootline using the following 693 environments variables: bootdev, bootfile, ipaddr, netmask, 694 serverip, gatewayip, hostname, othbootargs. 695 It loads the vxWorks image pointed bootfile. 696 697 Note: If a "bootargs" environment is defined, it will overwride 698 the defaults discussed just above. 699 700- Cache Configuration: 701 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 702 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 703 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 704 705- Cache Configuration for ARM: 706 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 707 controller 708 CONFIG_SYS_PL310_BASE - Physical base address of PL310 709 controller register space 710 711- Serial Ports: 712 CONFIG_PL010_SERIAL 713 714 Define this if you want support for Amba PrimeCell PL010 UARTs. 715 716 CONFIG_PL011_SERIAL 717 718 Define this if you want support for Amba PrimeCell PL011 UARTs. 719 720 CONFIG_PL011_CLOCK 721 722 If you have Amba PrimeCell PL011 UARTs, set this variable to 723 the clock speed of the UARTs. 724 725 CONFIG_PL01x_PORTS 726 727 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 728 define this to a list of base addresses for each (supported) 729 port. See e.g. include/configs/versatile.h 730 731 CONFIG_SERIAL_HW_FLOW_CONTROL 732 733 Define this variable to enable hw flow control in serial driver. 734 Current user of this option is drivers/serial/nsl16550.c driver 735 736- Console Interface: 737 Depending on board, define exactly one serial port 738 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 739 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 740 console by defining CONFIG_8xx_CONS_NONE 741 742 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 743 port routines must be defined elsewhere 744 (i.e. serial_init(), serial_getc(), ...) 745 746- Console Baudrate: 747 CONFIG_BAUDRATE - in bps 748 Select one of the baudrates listed in 749 CONFIG_SYS_BAUDRATE_TABLE, see below. 750 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 751 752- Console Rx buffer length 753 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 754 the maximum receive buffer length for the SMC. 755 This option is actual only for 82xx and 8xx possible. 756 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 757 must be defined, to setup the maximum idle timeout for 758 the SMC. 759 760- Autoboot Command: 761 CONFIG_BOOTCOMMAND 762 Only needed when CONFIG_BOOTDELAY is enabled; 763 define a command string that is automatically executed 764 when no character is read on the console interface 765 within "Boot Delay" after reset. 766 767 CONFIG_BOOTARGS 768 This can be used to pass arguments to the bootm 769 command. The value of CONFIG_BOOTARGS goes into the 770 environment value "bootargs". 771 772 CONFIG_RAMBOOT and CONFIG_NFSBOOT 773 The value of these goes into the environment as 774 "ramboot" and "nfsboot" respectively, and can be used 775 as a convenience, when switching between booting from 776 RAM and NFS. 777 778- Bootcount: 779 CONFIG_BOOTCOUNT_LIMIT 780 Implements a mechanism for detecting a repeating reboot 781 cycle, see: 782 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit 783 784 CONFIG_BOOTCOUNT_ENV 785 If no softreset save registers are found on the hardware 786 "bootcount" is stored in the environment. To prevent a 787 saveenv on all reboots, the environment variable 788 "upgrade_available" is used. If "upgrade_available" is 789 0, "bootcount" is always 0, if "upgrade_available" is 790 1 "bootcount" is incremented in the environment. 791 So the Userspace Applikation must set the "upgrade_available" 792 and "bootcount" variable to 0, if a boot was successfully. 793 794- Pre-Boot Commands: 795 CONFIG_PREBOOT 796 797 When this option is #defined, the existence of the 798 environment variable "preboot" will be checked 799 immediately before starting the CONFIG_BOOTDELAY 800 countdown and/or running the auto-boot command resp. 801 entering interactive mode. 802 803 This feature is especially useful when "preboot" is 804 automatically generated or modified. For an example 805 see the LWMON board specific code: here "preboot" is 806 modified when the user holds down a certain 807 combination of keys on the (special) keyboard when 808 booting the systems 809 810- Serial Download Echo Mode: 811 CONFIG_LOADS_ECHO 812 If defined to 1, all characters received during a 813 serial download (using the "loads" command) are 814 echoed back. This might be needed by some terminal 815 emulations (like "cu"), but may as well just take 816 time on others. This setting #define's the initial 817 value of the "loads_echo" environment variable. 818 819- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 820 CONFIG_KGDB_BAUDRATE 821 Select one of the baudrates listed in 822 CONFIG_SYS_BAUDRATE_TABLE, see below. 823 824- Monitor Functions: 825 Monitor commands can be included or excluded 826 from the build by using the #include files 827 <config_cmd_all.h> and #undef'ing unwanted 828 commands, or adding #define's for wanted commands. 829 830 The default command configuration includes all commands 831 except those marked below with a "*". 832 833 CONFIG_CMD_AES AES 128 CBC encrypt/decrypt 834 CONFIG_CMD_ASKENV * ask for env variable 835 CONFIG_CMD_BDI bdinfo 836 CONFIG_CMD_BEDBUG * Include BedBug Debugger 837 CONFIG_CMD_BMP * BMP support 838 CONFIG_CMD_BSP * Board specific commands 839 CONFIG_CMD_BOOTD bootd 840 CONFIG_CMD_BOOTI * ARM64 Linux kernel Image support 841 CONFIG_CMD_CACHE * icache, dcache 842 CONFIG_CMD_CLK * clock command support 843 CONFIG_CMD_CONSOLE coninfo 844 CONFIG_CMD_CRC32 * crc32 845 CONFIG_CMD_DATE * support for RTC, date/time... 846 CONFIG_CMD_DHCP * DHCP support 847 CONFIG_CMD_DIAG * Diagnostics 848 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands 849 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command 850 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd 851 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command 852 CONFIG_CMD_DTT * Digital Therm and Thermostat 853 CONFIG_CMD_ECHO echo arguments 854 CONFIG_CMD_EDITENV edit env variable 855 CONFIG_CMD_EEPROM * EEPROM read/write support 856 CONFIG_CMD_EEPROM_LAYOUT* EEPROM layout aware commands 857 CONFIG_CMD_ELF * bootelf, bootvx 858 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks 859 CONFIG_CMD_ENV_FLAGS * display details about env flags 860 CONFIG_CMD_ENV_EXISTS * check existence of env variable 861 CONFIG_CMD_EXPORTENV * export the environment 862 CONFIG_CMD_EXT2 * ext2 command support 863 CONFIG_CMD_EXT4 * ext4 command support 864 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls) 865 that work for multiple fs types 866 CONFIG_CMD_FS_UUID * Look up a filesystem UUID 867 CONFIG_CMD_SAVEENV saveenv 868 CONFIG_CMD_FDC * Floppy Disk Support 869 CONFIG_CMD_FAT * FAT command support 870 CONFIG_CMD_FLASH flinfo, erase, protect 871 CONFIG_CMD_FPGA FPGA device initialization support 872 CONFIG_CMD_FUSE * Device fuse support 873 CONFIG_CMD_GETTIME * Get time since boot 874 CONFIG_CMD_GO * the 'go' command (exec code) 875 CONFIG_CMD_GREPENV * search environment 876 CONFIG_CMD_HASH * calculate hash / digest 877 CONFIG_CMD_I2C * I2C serial bus support 878 CONFIG_CMD_IDE * IDE harddisk support 879 CONFIG_CMD_IMI iminfo 880 CONFIG_CMD_IMLS List all images found in NOR flash 881 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash 882 CONFIG_CMD_IMMAP * IMMR dump support 883 CONFIG_CMD_IOTRACE * I/O tracing for debugging 884 CONFIG_CMD_IMPORTENV * import an environment 885 CONFIG_CMD_INI * import data from an ini file into the env 886 CONFIG_CMD_IRQ * irqinfo 887 CONFIG_CMD_ITEST Integer/string test of 2 values 888 CONFIG_CMD_JFFS2 * JFFS2 Support 889 CONFIG_CMD_KGDB * kgdb 890 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader) 891 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration 892 (169.254.*.*) 893 CONFIG_CMD_LOADB loadb 894 CONFIG_CMD_LOADS loads 895 CONFIG_CMD_MD5SUM * print md5 message digest 896 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 897 CONFIG_CMD_MEMINFO * Display detailed memory information 898 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 899 loop, loopw 900 CONFIG_CMD_MEMTEST * mtest 901 CONFIG_CMD_MISC Misc functions like sleep etc 902 CONFIG_CMD_MMC * MMC memory mapped support 903 CONFIG_CMD_MII * MII utility commands 904 CONFIG_CMD_MTDPARTS * MTD partition support 905 CONFIG_CMD_NAND * NAND support 906 CONFIG_CMD_NET bootp, tftpboot, rarpboot 907 CONFIG_CMD_NFS NFS support 908 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 909 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 910 CONFIG_CMD_PCI * pciinfo 911 CONFIG_CMD_PCMCIA * PCMCIA support 912 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 913 host 914 CONFIG_CMD_PORTIO * Port I/O 915 CONFIG_CMD_READ * Read raw data from partition 916 CONFIG_CMD_REGINFO * Register dump 917 CONFIG_CMD_RUN run command in env variable 918 CONFIG_CMD_SANDBOX * sb command to access sandbox features 919 CONFIG_CMD_SAVES * save S record dump 920 CONFIG_SCSI * SCSI Support 921 CONFIG_CMD_SDRAM * print SDRAM configuration information 922 (requires CONFIG_CMD_I2C) 923 CONFIG_CMD_SETGETDCR Support for DCR Register access 924 (4xx only) 925 CONFIG_CMD_SF * Read/write/erase SPI NOR flash 926 CONFIG_CMD_SHA1SUM * print sha1 memory digest 927 (requires CONFIG_CMD_MEMORY) 928 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x 929 CONFIG_CMD_SOURCE "source" command Support 930 CONFIG_CMD_SPI * SPI serial bus support 931 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 932 CONFIG_CMD_TFTPPUT * TFTP put command (upload) 933 CONFIG_CMD_TIME * run command and report execution time (ARM specific) 934 CONFIG_CMD_TIMER * access to the system tick timer 935 CONFIG_CMD_USB * USB support 936 CONFIG_CMD_CDP * Cisco Discover Protocol support 937 CONFIG_CMD_MFSL * Microblaze FSL support 938 CONFIG_CMD_XIMG Load part of Multi Image 939 CONFIG_CMD_UUID * Generate random UUID or GUID string 940 941 EXAMPLE: If you want all functions except of network 942 support you can write: 943 944 #include "config_cmd_all.h" 945 #undef CONFIG_CMD_NET 946 947 Other Commands: 948 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 949 950 Note: Don't enable the "icache" and "dcache" commands 951 (configuration option CONFIG_CMD_CACHE) unless you know 952 what you (and your U-Boot users) are doing. Data 953 cache cannot be enabled on systems like the 8xx or 954 8260 (where accesses to the IMMR region must be 955 uncached), and it cannot be disabled on all other 956 systems where we (mis-) use the data cache to hold an 957 initial stack and some data. 958 959 960 XXX - this list needs to get updated! 961 962- Removal of commands 963 If no commands are needed to boot, you can disable 964 CONFIG_CMDLINE to remove them. In this case, the command line 965 will not be available, and when U-Boot wants to execute the 966 boot command (on start-up) it will call board_run_command() 967 instead. This can reduce image size significantly for very 968 simple boot procedures. 969 970- Regular expression support: 971 CONFIG_REGEX 972 If this variable is defined, U-Boot is linked against 973 the SLRE (Super Light Regular Expression) library, 974 which adds regex support to some commands, as for 975 example "env grep" and "setexpr". 976 977- Device tree: 978 CONFIG_OF_CONTROL 979 If this variable is defined, U-Boot will use a device tree 980 to configure its devices, instead of relying on statically 981 compiled #defines in the board file. This option is 982 experimental and only available on a few boards. The device 983 tree is available in the global data as gd->fdt_blob. 984 985 U-Boot needs to get its device tree from somewhere. This can 986 be done using one of the two options below: 987 988 CONFIG_OF_EMBED 989 If this variable is defined, U-Boot will embed a device tree 990 binary in its image. This device tree file should be in the 991 board directory and called <soc>-<board>.dts. The binary file 992 is then picked up in board_init_f() and made available through 993 the global data structure as gd->blob. 994 995 CONFIG_OF_SEPARATE 996 If this variable is defined, U-Boot will build a device tree 997 binary. It will be called u-boot.dtb. Architecture-specific 998 code will locate it at run-time. Generally this works by: 999 1000 cat u-boot.bin u-boot.dtb >image.bin 1001 1002 and in fact, U-Boot does this for you, creating a file called 1003 u-boot-dtb.bin which is useful in the common case. You can 1004 still use the individual files if you need something more 1005 exotic. 1006 1007- Watchdog: 1008 CONFIG_WATCHDOG 1009 If this variable is defined, it enables watchdog 1010 support for the SoC. There must be support in the SoC 1011 specific code for a watchdog. For the 8xx and 8260 1012 CPUs, the SIU Watchdog feature is enabled in the SYPCR 1013 register. When supported for a specific SoC is 1014 available, then no further board specific code should 1015 be needed to use it. 1016 1017 CONFIG_HW_WATCHDOG 1018 When using a watchdog circuitry external to the used 1019 SoC, then define this variable and provide board 1020 specific code for the "hw_watchdog_reset" function. 1021 1022 CONFIG_AT91_HW_WDT_TIMEOUT 1023 specify the timeout in seconds. default 2 seconds. 1024 1025- U-Boot Version: 1026 CONFIG_VERSION_VARIABLE 1027 If this variable is defined, an environment variable 1028 named "ver" is created by U-Boot showing the U-Boot 1029 version as printed by the "version" command. 1030 Any change to this variable will be reverted at the 1031 next reset. 1032 1033- Real-Time Clock: 1034 1035 When CONFIG_CMD_DATE is selected, the type of the RTC 1036 has to be selected, too. Define exactly one of the 1037 following options: 1038 1039 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 1040 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 1041 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 1042 CONFIG_RTC_MC146818 - use MC146818 RTC 1043 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 1044 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 1045 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 1046 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC 1047 CONFIG_RTC_DS164x - use Dallas DS164x RTC 1048 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 1049 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 1050 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 1051 CONFIG_SYS_RV3029_TCR - enable trickle charger on 1052 RV3029 RTC. 1053 1054 Note that if the RTC uses I2C, then the I2C interface 1055 must also be configured. See I2C Support, below. 1056 1057- GPIO Support: 1058 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 1059 1060 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 1061 chip-ngpio pairs that tell the PCA953X driver the number of 1062 pins supported by a particular chip. 1063 1064 Note that if the GPIO device uses I2C, then the I2C interface 1065 must also be configured. See I2C Support, below. 1066 1067- I/O tracing: 1068 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O 1069 accesses and can checksum them or write a list of them out 1070 to memory. See the 'iotrace' command for details. This is 1071 useful for testing device drivers since it can confirm that 1072 the driver behaves the same way before and after a code 1073 change. Currently this is supported on sandbox and arm. To 1074 add support for your architecture, add '#include <iotrace.h>' 1075 to the bottom of arch/<arch>/include/asm/io.h and test. 1076 1077 Example output from the 'iotrace stats' command is below. 1078 Note that if the trace buffer is exhausted, the checksum will 1079 still continue to operate. 1080 1081 iotrace is enabled 1082 Start: 10000000 (buffer start address) 1083 Size: 00010000 (buffer size) 1084 Offset: 00000120 (current buffer offset) 1085 Output: 10000120 (start + offset) 1086 Count: 00000018 (number of trace records) 1087 CRC32: 9526fb66 (CRC32 of all trace records) 1088 1089- Timestamp Support: 1090 1091 When CONFIG_TIMESTAMP is selected, the timestamp 1092 (date and time) of an image is printed by image 1093 commands like bootm or iminfo. This option is 1094 automatically enabled when you select CONFIG_CMD_DATE . 1095 1096- Partition Labels (disklabels) Supported: 1097 Zero or more of the following: 1098 CONFIG_MAC_PARTITION Apple's MacOS partition table. 1099 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the 1100 Intel architecture, USB sticks, etc. 1101 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc. 1102 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the 1103 bootloader. Note 2TB partition limit; see 1104 disk/part_efi.c 1105 CONFIG_MTD_PARTITIONS Memory Technology Device partition table. 1106 1107 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 1108 CONFIG_SCSI) you must configure support for at 1109 least one non-MTD partition type as well. 1110 1111- IDE Reset method: 1112 CONFIG_IDE_RESET_ROUTINE - this is defined in several 1113 board configurations files but used nowhere! 1114 1115 CONFIG_IDE_RESET - is this is defined, IDE Reset will 1116 be performed by calling the function 1117 ide_set_reset(int reset) 1118 which has to be defined in a board specific file 1119 1120- ATAPI Support: 1121 CONFIG_ATAPI 1122 1123 Set this to enable ATAPI support. 1124 1125- LBA48 Support 1126 CONFIG_LBA48 1127 1128 Set this to enable support for disks larger than 137GB 1129 Also look at CONFIG_SYS_64BIT_LBA. 1130 Whithout these , LBA48 support uses 32bit variables and will 'only' 1131 support disks up to 2.1TB. 1132 1133 CONFIG_SYS_64BIT_LBA: 1134 When enabled, makes the IDE subsystem use 64bit sector addresses. 1135 Default is 32bit. 1136 1137- SCSI Support: 1138 At the moment only there is only support for the 1139 SYM53C8XX SCSI controller; define 1140 CONFIG_SCSI_SYM53C8XX to enable it. 1141 1142 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 1143 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 1144 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 1145 maximum numbers of LUNs, SCSI ID's and target 1146 devices. 1147 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 1148 1149 The environment variable 'scsidevs' is set to the number of 1150 SCSI devices found during the last scan. 1151 1152- NETWORK Support (PCI): 1153 CONFIG_E1000 1154 Support for Intel 8254x/8257x gigabit chips. 1155 1156 CONFIG_E1000_SPI 1157 Utility code for direct access to the SPI bus on Intel 8257x. 1158 This does not do anything useful unless you set at least one 1159 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 1160 1161 CONFIG_E1000_SPI_GENERIC 1162 Allow generic access to the SPI bus on the Intel 8257x, for 1163 example with the "sspi" command. 1164 1165 CONFIG_CMD_E1000 1166 Management command for E1000 devices. When used on devices 1167 with SPI support you can reprogram the EEPROM from U-Boot. 1168 1169 CONFIG_EEPRO100 1170 Support for Intel 82557/82559/82559ER chips. 1171 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 1172 write routine for first time initialisation. 1173 1174 CONFIG_TULIP 1175 Support for Digital 2114x chips. 1176 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 1177 modem chip initialisation (KS8761/QS6611). 1178 1179 CONFIG_NATSEMI 1180 Support for National dp83815 chips. 1181 1182 CONFIG_NS8382X 1183 Support for National dp8382[01] gigabit chips. 1184 1185- NETWORK Support (other): 1186 1187 CONFIG_DRIVER_AT91EMAC 1188 Support for AT91RM9200 EMAC. 1189 1190 CONFIG_RMII 1191 Define this to use reduced MII inteface 1192 1193 CONFIG_DRIVER_AT91EMAC_QUIET 1194 If this defined, the driver is quiet. 1195 The driver doen't show link status messages. 1196 1197 CONFIG_CALXEDA_XGMAC 1198 Support for the Calxeda XGMAC device 1199 1200 CONFIG_LAN91C96 1201 Support for SMSC's LAN91C96 chips. 1202 1203 CONFIG_LAN91C96_USE_32_BIT 1204 Define this to enable 32 bit addressing 1205 1206 CONFIG_SMC91111 1207 Support for SMSC's LAN91C111 chip 1208 1209 CONFIG_SMC91111_BASE 1210 Define this to hold the physical address 1211 of the device (I/O space) 1212 1213 CONFIG_SMC_USE_32_BIT 1214 Define this if data bus is 32 bits 1215 1216 CONFIG_SMC_USE_IOFUNCS 1217 Define this to use i/o functions instead of macros 1218 (some hardware wont work with macros) 1219 1220 CONFIG_DRIVER_TI_EMAC 1221 Support for davinci emac 1222 1223 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1224 Define this if you have more then 3 PHYs. 1225 1226 CONFIG_FTGMAC100 1227 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1228 1229 CONFIG_FTGMAC100_EGIGA 1230 Define this to use GE link update with gigabit PHY. 1231 Define this if FTGMAC100 is connected to gigabit PHY. 1232 If your system has 10/100 PHY only, it might not occur 1233 wrong behavior. Because PHY usually return timeout or 1234 useless data when polling gigabit status and gigabit 1235 control registers. This behavior won't affect the 1236 correctnessof 10/100 link speed update. 1237 1238 CONFIG_SMC911X 1239 Support for SMSC's LAN911x and LAN921x chips 1240 1241 CONFIG_SMC911X_BASE 1242 Define this to hold the physical address 1243 of the device (I/O space) 1244 1245 CONFIG_SMC911X_32_BIT 1246 Define this if data bus is 32 bits 1247 1248 CONFIG_SMC911X_16_BIT 1249 Define this if data bus is 16 bits. If your processor 1250 automatically converts one 32 bit word to two 16 bit 1251 words you may also try CONFIG_SMC911X_32_BIT. 1252 1253 CONFIG_SH_ETHER 1254 Support for Renesas on-chip Ethernet controller 1255 1256 CONFIG_SH_ETHER_USE_PORT 1257 Define the number of ports to be used 1258 1259 CONFIG_SH_ETHER_PHY_ADDR 1260 Define the ETH PHY's address 1261 1262 CONFIG_SH_ETHER_CACHE_WRITEBACK 1263 If this option is set, the driver enables cache flush. 1264 1265- PWM Support: 1266 CONFIG_PWM_IMX 1267 Support for PWM module on the imx6. 1268 1269- TPM Support: 1270 CONFIG_TPM 1271 Support TPM devices. 1272 1273 CONFIG_TPM_TIS_INFINEON 1274 Support for Infineon i2c bus TPM devices. Only one device 1275 per system is supported at this time. 1276 1277 CONFIG_TPM_TIS_I2C_BURST_LIMITATION 1278 Define the burst count bytes upper limit 1279 1280 CONFIG_TPM_ST33ZP24 1281 Support for STMicroelectronics TPM devices. Requires DM_TPM support. 1282 1283 CONFIG_TPM_ST33ZP24_I2C 1284 Support for STMicroelectronics ST33ZP24 I2C devices. 1285 Requires TPM_ST33ZP24 and I2C. 1286 1287 CONFIG_TPM_ST33ZP24_SPI 1288 Support for STMicroelectronics ST33ZP24 SPI devices. 1289 Requires TPM_ST33ZP24 and SPI. 1290 1291 CONFIG_TPM_ATMEL_TWI 1292 Support for Atmel TWI TPM device. Requires I2C support. 1293 1294 CONFIG_TPM_TIS_LPC 1295 Support for generic parallel port TPM devices. Only one device 1296 per system is supported at this time. 1297 1298 CONFIG_TPM_TIS_BASE_ADDRESS 1299 Base address where the generic TPM device is mapped 1300 to. Contemporary x86 systems usually map it at 1301 0xfed40000. 1302 1303 CONFIG_CMD_TPM 1304 Add tpm monitor functions. 1305 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also 1306 provides monitor access to authorized functions. 1307 1308 CONFIG_TPM 1309 Define this to enable the TPM support library which provides 1310 functional interfaces to some TPM commands. 1311 Requires support for a TPM device. 1312 1313 CONFIG_TPM_AUTH_SESSIONS 1314 Define this to enable authorized functions in the TPM library. 1315 Requires CONFIG_TPM and CONFIG_SHA1. 1316 1317- USB Support: 1318 At the moment only the UHCI host controller is 1319 supported (PIP405, MIP405, MPC5200); define 1320 CONFIG_USB_UHCI to enable it. 1321 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1322 and define CONFIG_USB_STORAGE to enable the USB 1323 storage devices. 1324 Note: 1325 Supported are USB Keyboards and USB Floppy drives 1326 (TEAC FD-05PUB). 1327 MPC5200 USB requires additional defines: 1328 CONFIG_USB_CLOCK 1329 for 528 MHz Clock: 0x0001bbbb 1330 CONFIG_PSC3_USB 1331 for USB on PSC3 1332 CONFIG_USB_CONFIG 1333 for differential drivers: 0x00001000 1334 for single ended drivers: 0x00005000 1335 for differential drivers on PSC3: 0x00000100 1336 for single ended drivers on PSC3: 0x00004100 1337 CONFIG_SYS_USB_EVENT_POLL 1338 May be defined to allow interrupt polling 1339 instead of using asynchronous interrupts 1340 1341 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the 1342 txfilltuning field in the EHCI controller on reset. 1343 1344 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2 1345 HW module registers. 1346 1347- USB Device: 1348 Define the below if you wish to use the USB console. 1349 Once firmware is rebuilt from a serial console issue the 1350 command "setenv stdin usbtty; setenv stdout usbtty" and 1351 attach your USB cable. The Unix command "dmesg" should print 1352 it has found a new device. The environment variable usbtty 1353 can be set to gserial or cdc_acm to enable your device to 1354 appear to a USB host as a Linux gserial device or a 1355 Common Device Class Abstract Control Model serial device. 1356 If you select usbtty = gserial you should be able to enumerate 1357 a Linux host by 1358 # modprobe usbserial vendor=0xVendorID product=0xProductID 1359 else if using cdc_acm, simply setting the environment 1360 variable usbtty to be cdc_acm should suffice. The following 1361 might be defined in YourBoardName.h 1362 1363 CONFIG_USB_DEVICE 1364 Define this to build a UDC device 1365 1366 CONFIG_USB_TTY 1367 Define this to have a tty type of device available to 1368 talk to the UDC device 1369 1370 CONFIG_USBD_HS 1371 Define this to enable the high speed support for usb 1372 device and usbtty. If this feature is enabled, a routine 1373 int is_usbd_high_speed(void) 1374 also needs to be defined by the driver to dynamically poll 1375 whether the enumeration has succeded at high speed or full 1376 speed. 1377 1378 CONFIG_SYS_CONSOLE_IS_IN_ENV 1379 Define this if you want stdin, stdout &/or stderr to 1380 be set to usbtty. 1381 1382 mpc8xx: 1383 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1384 Derive USB clock from external clock "blah" 1385 - CONFIG_SYS_USB_EXTC_CLK 0x02 1386 1387 If you have a USB-IF assigned VendorID then you may wish to 1388 define your own vendor specific values either in BoardName.h 1389 or directly in usbd_vendor_info.h. If you don't define 1390 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1391 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1392 should pretend to be a Linux device to it's target host. 1393 1394 CONFIG_USBD_MANUFACTURER 1395 Define this string as the name of your company for 1396 - CONFIG_USBD_MANUFACTURER "my company" 1397 1398 CONFIG_USBD_PRODUCT_NAME 1399 Define this string as the name of your product 1400 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1401 1402 CONFIG_USBD_VENDORID 1403 Define this as your assigned Vendor ID from the USB 1404 Implementors Forum. This *must* be a genuine Vendor ID 1405 to avoid polluting the USB namespace. 1406 - CONFIG_USBD_VENDORID 0xFFFF 1407 1408 CONFIG_USBD_PRODUCTID 1409 Define this as the unique Product ID 1410 for your device 1411 - CONFIG_USBD_PRODUCTID 0xFFFF 1412 1413- ULPI Layer Support: 1414 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via 1415 the generic ULPI layer. The generic layer accesses the ULPI PHY 1416 via the platform viewport, so you need both the genric layer and 1417 the viewport enabled. Currently only Chipidea/ARC based 1418 viewport is supported. 1419 To enable the ULPI layer support, define CONFIG_USB_ULPI and 1420 CONFIG_USB_ULPI_VIEWPORT in your board configuration file. 1421 If your ULPI phy needs a different reference clock than the 1422 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to 1423 the appropriate value in Hz. 1424 1425- MMC Support: 1426 The MMC controller on the Intel PXA is supported. To 1427 enable this define CONFIG_MMC. The MMC can be 1428 accessed from the boot prompt by mapping the device 1429 to physical memory similar to flash. Command line is 1430 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1431 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1432 1433 CONFIG_SH_MMCIF 1434 Support for Renesas on-chip MMCIF controller 1435 1436 CONFIG_SH_MMCIF_ADDR 1437 Define the base address of MMCIF registers 1438 1439 CONFIG_SH_MMCIF_CLK 1440 Define the clock frequency for MMCIF 1441 1442 CONFIG_SUPPORT_EMMC_BOOT 1443 Enable some additional features of the eMMC boot partitions. 1444 1445 CONFIG_SUPPORT_EMMC_RPMB 1446 Enable the commands for reading, writing and programming the 1447 key for the Replay Protection Memory Block partition in eMMC. 1448 1449- USB Device Firmware Update (DFU) class support: 1450 CONFIG_USB_FUNCTION_DFU 1451 This enables the USB portion of the DFU USB class 1452 1453 CONFIG_CMD_DFU 1454 This enables the command "dfu" which is used to have 1455 U-Boot create a DFU class device via USB. This command 1456 requires that the "dfu_alt_info" environment variable be 1457 set and define the alt settings to expose to the host. 1458 1459 CONFIG_DFU_MMC 1460 This enables support for exposing (e)MMC devices via DFU. 1461 1462 CONFIG_DFU_NAND 1463 This enables support for exposing NAND devices via DFU. 1464 1465 CONFIG_DFU_RAM 1466 This enables support for exposing RAM via DFU. 1467 Note: DFU spec refer to non-volatile memory usage, but 1468 allow usages beyond the scope of spec - here RAM usage, 1469 one that would help mostly the developer. 1470 1471 CONFIG_SYS_DFU_DATA_BUF_SIZE 1472 Dfu transfer uses a buffer before writing data to the 1473 raw storage device. Make the size (in bytes) of this buffer 1474 configurable. The size of this buffer is also configurable 1475 through the "dfu_bufsiz" environment variable. 1476 1477 CONFIG_SYS_DFU_MAX_FILE_SIZE 1478 When updating files rather than the raw storage device, 1479 we use a static buffer to copy the file into and then write 1480 the buffer once we've been given the whole file. Define 1481 this to the maximum filesize (in bytes) for the buffer. 1482 Default is 4 MiB if undefined. 1483 1484 DFU_DEFAULT_POLL_TIMEOUT 1485 Poll timeout [ms], is the timeout a device can send to the 1486 host. The host must wait for this timeout before sending 1487 a subsequent DFU_GET_STATUS request to the device. 1488 1489 DFU_MANIFEST_POLL_TIMEOUT 1490 Poll timeout [ms], which the device sends to the host when 1491 entering dfuMANIFEST state. Host waits this timeout, before 1492 sending again an USB request to the device. 1493 1494- USB Device Android Fastboot support: 1495 CONFIG_USB_FUNCTION_FASTBOOT 1496 This enables the USB part of the fastboot gadget 1497 1498 CONFIG_CMD_FASTBOOT 1499 This enables the command "fastboot" which enables the Android 1500 fastboot mode for the platform's USB device. Fastboot is a USB 1501 protocol for downloading images, flashing and device control 1502 used on Android devices. 1503 See doc/README.android-fastboot for more information. 1504 1505 CONFIG_ANDROID_BOOT_IMAGE 1506 This enables support for booting images which use the Android 1507 image format header. 1508 1509 CONFIG_FASTBOOT_BUF_ADDR 1510 The fastboot protocol requires a large memory buffer for 1511 downloads. Define this to the starting RAM address to use for 1512 downloaded images. 1513 1514 CONFIG_FASTBOOT_BUF_SIZE 1515 The fastboot protocol requires a large memory buffer for 1516 downloads. This buffer should be as large as possible for a 1517 platform. Define this to the size available RAM for fastboot. 1518 1519 CONFIG_FASTBOOT_FLASH 1520 The fastboot protocol includes a "flash" command for writing 1521 the downloaded image to a non-volatile storage device. Define 1522 this to enable the "fastboot flash" command. 1523 1524 CONFIG_FASTBOOT_FLASH_MMC_DEV 1525 The fastboot "flash" command requires additional information 1526 regarding the non-volatile storage device. Define this to 1527 the eMMC device that fastboot should use to store the image. 1528 1529 CONFIG_FASTBOOT_GPT_NAME 1530 The fastboot "flash" command supports writing the downloaded 1531 image to the Protective MBR and the Primary GUID Partition 1532 Table. (Additionally, this downloaded image is post-processed 1533 to generate and write the Backup GUID Partition Table.) 1534 This occurs when the specified "partition name" on the 1535 "fastboot flash" command line matches this value. 1536 The default is "gpt" if undefined. 1537 1538 CONFIG_FASTBOOT_MBR_NAME 1539 The fastboot "flash" command supports writing the downloaded 1540 image to DOS MBR. 1541 This occurs when the "partition name" specified on the 1542 "fastboot flash" command line matches this value. 1543 If not defined the default value "mbr" is used. 1544 1545- Journaling Flash filesystem support: 1546 CONFIG_JFFS2_NAND 1547 Define these for a default partition on a NAND device 1548 1549 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1550 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1551 Define these for a default partition on a NOR device 1552 1553- FAT(File Allocation Table) filesystem write function support: 1554 CONFIG_FAT_WRITE 1555 1556 Define this to enable support for saving memory data as a 1557 file in FAT formatted partition. 1558 1559 This will also enable the command "fatwrite" enabling the 1560 user to write files to FAT. 1561 1562- CBFS (Coreboot Filesystem) support: 1563 CONFIG_CMD_CBFS 1564 1565 Define this to enable support for reading from a Coreboot 1566 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls 1567 and cbfsload. 1568 1569- FAT(File Allocation Table) filesystem cluster size: 1570 CONFIG_FS_FAT_MAX_CLUSTSIZE 1571 1572 Define the max cluster size for fat operations else 1573 a default value of 65536 will be defined. 1574 1575- Keyboard Support: 1576 See Kconfig help for available keyboard drivers. 1577 1578 CONFIG_KEYBOARD 1579 1580 Define this to enable a custom keyboard support. 1581 This simply calls drv_keyboard_init() which must be 1582 defined in your board-specific files. This option is deprecated 1583 and is only used by novena. For new boards, use driver model 1584 instead. 1585 1586- Video support: 1587 CONFIG_FSL_DIU_FB 1588 Enable the Freescale DIU video driver. Reference boards for 1589 SOCs that have a DIU should define this macro to enable DIU 1590 support, and should also define these other macros: 1591 1592 CONFIG_SYS_DIU_ADDR 1593 CONFIG_VIDEO 1594 CONFIG_CMD_BMP 1595 CONFIG_CFB_CONSOLE 1596 CONFIG_VIDEO_SW_CURSOR 1597 CONFIG_VGA_AS_SINGLE_DEVICE 1598 CONFIG_VIDEO_LOGO 1599 CONFIG_VIDEO_BMP_LOGO 1600 1601 The DIU driver will look for the 'video-mode' environment 1602 variable, and if defined, enable the DIU as a console during 1603 boot. See the documentation file doc/README.video for a 1604 description of this variable. 1605 1606- LCD Support: CONFIG_LCD 1607 1608 Define this to enable LCD support (for output to LCD 1609 display); also select one of the supported displays 1610 by defining one of these: 1611 1612 CONFIG_ATMEL_LCD: 1613 1614 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1615 1616 CONFIG_NEC_NL6448AC33: 1617 1618 NEC NL6448AC33-18. Active, color, single scan. 1619 1620 CONFIG_NEC_NL6448BC20 1621 1622 NEC NL6448BC20-08. 6.5", 640x480. 1623 Active, color, single scan. 1624 1625 CONFIG_NEC_NL6448BC33_54 1626 1627 NEC NL6448BC33-54. 10.4", 640x480. 1628 Active, color, single scan. 1629 1630 CONFIG_SHARP_16x9 1631 1632 Sharp 320x240. Active, color, single scan. 1633 It isn't 16x9, and I am not sure what it is. 1634 1635 CONFIG_SHARP_LQ64D341 1636 1637 Sharp LQ64D341 display, 640x480. 1638 Active, color, single scan. 1639 1640 CONFIG_HLD1045 1641 1642 HLD1045 display, 640x480. 1643 Active, color, single scan. 1644 1645 CONFIG_OPTREX_BW 1646 1647 Optrex CBL50840-2 NF-FW 99 22 M5 1648 or 1649 Hitachi LMG6912RPFC-00T 1650 or 1651 Hitachi SP14Q002 1652 1653 320x240. Black & white. 1654 1655 Normally display is black on white background; define 1656 CONFIG_SYS_WHITE_ON_BLACK to get it inverted. 1657 1658 CONFIG_LCD_ALIGNMENT 1659 1660 Normally the LCD is page-aligned (typically 4KB). If this is 1661 defined then the LCD will be aligned to this value instead. 1662 For ARM it is sometimes useful to use MMU_SECTION_SIZE 1663 here, since it is cheaper to change data cache settings on 1664 a per-section basis. 1665 1666 1667 CONFIG_LCD_ROTATION 1668 1669 Sometimes, for example if the display is mounted in portrait 1670 mode or even if it's mounted landscape but rotated by 180degree, 1671 we need to rotate our content of the display relative to the 1672 framebuffer, so that user can read the messages which are 1673 printed out. 1674 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be 1675 initialized with a given rotation from "vl_rot" out of 1676 "vidinfo_t" which is provided by the board specific code. 1677 The value for vl_rot is coded as following (matching to 1678 fbcon=rotate:<n> linux-kernel commandline): 1679 0 = no rotation respectively 0 degree 1680 1 = 90 degree rotation 1681 2 = 180 degree rotation 1682 3 = 270 degree rotation 1683 1684 If CONFIG_LCD_ROTATION is not defined, the console will be 1685 initialized with 0degree rotation. 1686 1687 CONFIG_LCD_BMP_RLE8 1688 1689 Support drawing of RLE8-compressed bitmaps on the LCD. 1690 1691 CONFIG_I2C_EDID 1692 1693 Enables an 'i2c edid' command which can read EDID 1694 information over I2C from an attached LCD display. 1695 1696- Splash Screen Support: CONFIG_SPLASH_SCREEN 1697 1698 If this option is set, the environment is checked for 1699 a variable "splashimage". If found, the usual display 1700 of logo, copyright and system information on the LCD 1701 is suppressed and the BMP image at the address 1702 specified in "splashimage" is loaded instead. The 1703 console is redirected to the "nulldev", too. This 1704 allows for a "silent" boot where a splash screen is 1705 loaded very quickly after power-on. 1706 1707 CONFIG_SPLASHIMAGE_GUARD 1708 1709 If this option is set, then U-Boot will prevent the environment 1710 variable "splashimage" from being set to a problematic address 1711 (see doc/README.displaying-bmps). 1712 This option is useful for targets where, due to alignment 1713 restrictions, an improperly aligned BMP image will cause a data 1714 abort. If you think you will not have problems with unaligned 1715 accesses (for example because your toolchain prevents them) 1716 there is no need to set this option. 1717 1718 CONFIG_SPLASH_SCREEN_ALIGN 1719 1720 If this option is set the splash image can be freely positioned 1721 on the screen. Environment variable "splashpos" specifies the 1722 position as "x,y". If a positive number is given it is used as 1723 number of pixel from left/top. If a negative number is given it 1724 is used as number of pixel from right/bottom. You can also 1725 specify 'm' for centering the image. 1726 1727 Example: 1728 setenv splashpos m,m 1729 => image at center of screen 1730 1731 setenv splashpos 30,20 1732 => image at x = 30 and y = 20 1733 1734 setenv splashpos -10,m 1735 => vertically centered image 1736 at x = dspWidth - bmpWidth - 9 1737 1738- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1739 1740 If this option is set, additionally to standard BMP 1741 images, gzipped BMP images can be displayed via the 1742 splashscreen support or the bmp command. 1743 1744- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 1745 1746 If this option is set, 8-bit RLE compressed BMP images 1747 can be displayed via the splashscreen support or the 1748 bmp command. 1749 1750- Compression support: 1751 CONFIG_GZIP 1752 1753 Enabled by default to support gzip compressed images. 1754 1755 CONFIG_BZIP2 1756 1757 If this option is set, support for bzip2 compressed 1758 images is included. If not, only uncompressed and gzip 1759 compressed images are supported. 1760 1761 NOTE: the bzip2 algorithm requires a lot of RAM, so 1762 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 1763 be at least 4MB. 1764 1765 CONFIG_LZMA 1766 1767 If this option is set, support for lzma compressed 1768 images is included. 1769 1770 Note: The LZMA algorithm adds between 2 and 4KB of code and it 1771 requires an amount of dynamic memory that is given by the 1772 formula: 1773 1774 (1846 + 768 << (lc + lp)) * sizeof(uint16) 1775 1776 Where lc and lp stand for, respectively, Literal context bits 1777 and Literal pos bits. 1778 1779 This value is upper-bounded by 14MB in the worst case. Anyway, 1780 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 1781 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 1782 a very small buffer. 1783 1784 Use the lzmainfo tool to determinate the lc and lp values and 1785 then calculate the amount of needed dynamic memory (ensuring 1786 the appropriate CONFIG_SYS_MALLOC_LEN value). 1787 1788 CONFIG_LZO 1789 1790 If this option is set, support for LZO compressed images 1791 is included. 1792 1793- MII/PHY support: 1794 CONFIG_PHY_ADDR 1795 1796 The address of PHY on MII bus. 1797 1798 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1799 1800 The clock frequency of the MII bus 1801 1802 CONFIG_PHY_GIGE 1803 1804 If this option is set, support for speed/duplex 1805 detection of gigabit PHY is included. 1806 1807 CONFIG_PHY_RESET_DELAY 1808 1809 Some PHY like Intel LXT971A need extra delay after 1810 reset before any MII register access is possible. 1811 For such PHY, set this option to the usec delay 1812 required. (minimum 300usec for LXT971A) 1813 1814 CONFIG_PHY_CMD_DELAY (ppc4xx) 1815 1816 Some PHY like Intel LXT971A need extra delay after 1817 command issued before MII status register can be read 1818 1819- IP address: 1820 CONFIG_IPADDR 1821 1822 Define a default value for the IP address to use for 1823 the default Ethernet interface, in case this is not 1824 determined through e.g. bootp. 1825 (Environment variable "ipaddr") 1826 1827- Server IP address: 1828 CONFIG_SERVERIP 1829 1830 Defines a default value for the IP address of a TFTP 1831 server to contact when using the "tftboot" command. 1832 (Environment variable "serverip") 1833 1834 CONFIG_KEEP_SERVERADDR 1835 1836 Keeps the server's MAC address, in the env 'serveraddr' 1837 for passing to bootargs (like Linux's netconsole option) 1838 1839- Gateway IP address: 1840 CONFIG_GATEWAYIP 1841 1842 Defines a default value for the IP address of the 1843 default router where packets to other networks are 1844 sent to. 1845 (Environment variable "gatewayip") 1846 1847- Subnet mask: 1848 CONFIG_NETMASK 1849 1850 Defines a default value for the subnet mask (or 1851 routing prefix) which is used to determine if an IP 1852 address belongs to the local subnet or needs to be 1853 forwarded through a router. 1854 (Environment variable "netmask") 1855 1856- Multicast TFTP Mode: 1857 CONFIG_MCAST_TFTP 1858 1859 Defines whether you want to support multicast TFTP as per 1860 rfc-2090; for example to work with atftp. Lets lots of targets 1861 tftp down the same boot image concurrently. Note: the Ethernet 1862 driver in use must provide a function: mcast() to join/leave a 1863 multicast group. 1864 1865- BOOTP Recovery Mode: 1866 CONFIG_BOOTP_RANDOM_DELAY 1867 1868 If you have many targets in a network that try to 1869 boot using BOOTP, you may want to avoid that all 1870 systems send out BOOTP requests at precisely the same 1871 moment (which would happen for instance at recovery 1872 from a power failure, when all systems will try to 1873 boot, thus flooding the BOOTP server. Defining 1874 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1875 inserted before sending out BOOTP requests. The 1876 following delays are inserted then: 1877 1878 1st BOOTP request: delay 0 ... 1 sec 1879 2nd BOOTP request: delay 0 ... 2 sec 1880 3rd BOOTP request: delay 0 ... 4 sec 1881 4th and following 1882 BOOTP requests: delay 0 ... 8 sec 1883 1884 CONFIG_BOOTP_ID_CACHE_SIZE 1885 1886 BOOTP packets are uniquely identified using a 32-bit ID. The 1887 server will copy the ID from client requests to responses and 1888 U-Boot will use this to determine if it is the destination of 1889 an incoming response. Some servers will check that addresses 1890 aren't in use before handing them out (usually using an ARP 1891 ping) and therefore take up to a few hundred milliseconds to 1892 respond. Network congestion may also influence the time it 1893 takes for a response to make it back to the client. If that 1894 time is too long, U-Boot will retransmit requests. In order 1895 to allow earlier responses to still be accepted after these 1896 retransmissions, U-Boot's BOOTP client keeps a small cache of 1897 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this 1898 cache. The default is to keep IDs for up to four outstanding 1899 requests. Increasing this will allow U-Boot to accept offers 1900 from a BOOTP client in networks with unusually high latency. 1901 1902- DHCP Advanced Options: 1903 You can fine tune the DHCP functionality by defining 1904 CONFIG_BOOTP_* symbols: 1905 1906 CONFIG_BOOTP_SUBNETMASK 1907 CONFIG_BOOTP_GATEWAY 1908 CONFIG_BOOTP_HOSTNAME 1909 CONFIG_BOOTP_NISDOMAIN 1910 CONFIG_BOOTP_BOOTPATH 1911 CONFIG_BOOTP_BOOTFILESIZE 1912 CONFIG_BOOTP_DNS 1913 CONFIG_BOOTP_DNS2 1914 CONFIG_BOOTP_SEND_HOSTNAME 1915 CONFIG_BOOTP_NTPSERVER 1916 CONFIG_BOOTP_TIMEOFFSET 1917 CONFIG_BOOTP_VENDOREX 1918 CONFIG_BOOTP_MAY_FAIL 1919 1920 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 1921 environment variable, not the BOOTP server. 1922 1923 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found 1924 after the configured retry count, the call will fail 1925 instead of starting over. This can be used to fail over 1926 to Link-local IP address configuration if the DHCP server 1927 is not available. 1928 1929 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 1930 serverip from a DHCP server, it is possible that more 1931 than one DNS serverip is offered to the client. 1932 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 1933 serverip will be stored in the additional environment 1934 variable "dnsip2". The first DNS serverip is always 1935 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 1936 is defined. 1937 1938 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 1939 to do a dynamic update of a DNS server. To do this, they 1940 need the hostname of the DHCP requester. 1941 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 1942 of the "hostname" environment variable is passed as 1943 option 12 to the DHCP server. 1944 1945 CONFIG_BOOTP_DHCP_REQUEST_DELAY 1946 1947 A 32bit value in microseconds for a delay between 1948 receiving a "DHCP Offer" and sending the "DHCP Request". 1949 This fixes a problem with certain DHCP servers that don't 1950 respond 100% of the time to a "DHCP request". E.g. On an 1951 AT91RM9200 processor running at 180MHz, this delay needed 1952 to be *at least* 15,000 usec before a Windows Server 2003 1953 DHCP server would reply 100% of the time. I recommend at 1954 least 50,000 usec to be safe. The alternative is to hope 1955 that one of the retries will be successful but note that 1956 the DHCP timeout and retry process takes a longer than 1957 this delay. 1958 1959 - Link-local IP address negotiation: 1960 Negotiate with other link-local clients on the local network 1961 for an address that doesn't require explicit configuration. 1962 This is especially useful if a DHCP server cannot be guaranteed 1963 to exist in all environments that the device must operate. 1964 1965 See doc/README.link-local for more information. 1966 1967 - CDP Options: 1968 CONFIG_CDP_DEVICE_ID 1969 1970 The device id used in CDP trigger frames. 1971 1972 CONFIG_CDP_DEVICE_ID_PREFIX 1973 1974 A two character string which is prefixed to the MAC address 1975 of the device. 1976 1977 CONFIG_CDP_PORT_ID 1978 1979 A printf format string which contains the ascii name of 1980 the port. Normally is set to "eth%d" which sets 1981 eth0 for the first Ethernet, eth1 for the second etc. 1982 1983 CONFIG_CDP_CAPABILITIES 1984 1985 A 32bit integer which indicates the device capabilities; 1986 0x00000010 for a normal host which does not forwards. 1987 1988 CONFIG_CDP_VERSION 1989 1990 An ascii string containing the version of the software. 1991 1992 CONFIG_CDP_PLATFORM 1993 1994 An ascii string containing the name of the platform. 1995 1996 CONFIG_CDP_TRIGGER 1997 1998 A 32bit integer sent on the trigger. 1999 2000 CONFIG_CDP_POWER_CONSUMPTION 2001 2002 A 16bit integer containing the power consumption of the 2003 device in .1 of milliwatts. 2004 2005 CONFIG_CDP_APPLIANCE_VLAN_TYPE 2006 2007 A byte containing the id of the VLAN. 2008 2009- Status LED: CONFIG_LED_STATUS 2010 2011 Several configurations allow to display the current 2012 status using a LED. For instance, the LED will blink 2013 fast while running U-Boot code, stop blinking as 2014 soon as a reply to a BOOTP request was received, and 2015 start blinking slow once the Linux kernel is running 2016 (supported by a status LED driver in the Linux 2017 kernel). Defining CONFIG_LED_STATUS enables this 2018 feature in U-Boot. 2019 2020 Additional options: 2021 2022 CONFIG_LED_STATUS_GPIO 2023 The status LED can be connected to a GPIO pin. 2024 In such cases, the gpio_led driver can be used as a 2025 status LED backend implementation. Define CONFIG_LED_STATUS_GPIO 2026 to include the gpio_led driver in the U-Boot binary. 2027 2028 CONFIG_GPIO_LED_INVERTED_TABLE 2029 Some GPIO connected LEDs may have inverted polarity in which 2030 case the GPIO high value corresponds to LED off state and 2031 GPIO low value corresponds to LED on state. 2032 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined 2033 with a list of GPIO LEDs that have inverted polarity. 2034 2035- CAN Support: CONFIG_CAN_DRIVER 2036 2037 Defining CONFIG_CAN_DRIVER enables CAN driver support 2038 on those systems that support this (optional) 2039 feature, like the TQM8xxL modules. 2040 2041- I2C Support: CONFIG_SYS_I2C 2042 2043 This enable the NEW i2c subsystem, and will allow you to use 2044 i2c commands at the u-boot command line (as long as you set 2045 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c 2046 based realtime clock chips or other i2c devices. See 2047 common/cmd_i2c.c for a description of the command line 2048 interface. 2049 2050 ported i2c driver to the new framework: 2051 - drivers/i2c/soft_i2c.c: 2052 - activate first bus with CONFIG_SYS_I2C_SOFT define 2053 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE 2054 for defining speed and slave address 2055 - activate second bus with I2C_SOFT_DECLARATIONS2 define 2056 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2 2057 for defining speed and slave address 2058 - activate third bus with I2C_SOFT_DECLARATIONS3 define 2059 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3 2060 for defining speed and slave address 2061 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define 2062 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4 2063 for defining speed and slave address 2064 2065 - drivers/i2c/fsl_i2c.c: 2066 - activate i2c driver with CONFIG_SYS_I2C_FSL 2067 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register 2068 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and 2069 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first 2070 bus. 2071 - If your board supports a second fsl i2c bus, define 2072 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset 2073 CONFIG_SYS_FSL_I2C2_SPEED for the speed and 2074 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the 2075 second bus. 2076 2077 - drivers/i2c/tegra_i2c.c: 2078 - activate this driver with CONFIG_SYS_I2C_TEGRA 2079 - This driver adds 4 i2c buses with a fix speed from 2080 100000 and the slave addr 0! 2081 2082 - drivers/i2c/ppc4xx_i2c.c 2083 - activate this driver with CONFIG_SYS_I2C_PPC4XX 2084 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0 2085 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1 2086 2087 - drivers/i2c/i2c_mxc.c 2088 - activate this driver with CONFIG_SYS_I2C_MXC 2089 - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1 2090 - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2 2091 - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3 2092 - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4 2093 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED 2094 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE 2095 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED 2096 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE 2097 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED 2098 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE 2099 - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED 2100 - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE 2101 If those defines are not set, default value is 100000 2102 for speed, and 0 for slave. 2103 2104 - drivers/i2c/rcar_i2c.c: 2105 - activate this driver with CONFIG_SYS_I2C_RCAR 2106 - This driver adds 4 i2c buses 2107 2108 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0 2109 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0 2110 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1 2111 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1 2112 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2 2113 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2 2114 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3 2115 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3 2116 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses 2117 2118 - drivers/i2c/sh_i2c.c: 2119 - activate this driver with CONFIG_SYS_I2C_SH 2120 - This driver adds from 2 to 5 i2c buses 2121 2122 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0 2123 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0 2124 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1 2125 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1 2126 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2 2127 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2 2128 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3 2129 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3 2130 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4 2131 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4 2132 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses 2133 2134 - drivers/i2c/omap24xx_i2c.c 2135 - activate this driver with CONFIG_SYS_I2C_OMAP24XX 2136 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0 2137 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0 2138 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1 2139 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1 2140 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2 2141 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2 2142 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3 2143 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3 2144 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4 2145 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4 2146 2147 - drivers/i2c/zynq_i2c.c 2148 - activate this driver with CONFIG_SYS_I2C_ZYNQ 2149 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting 2150 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr 2151 2152 - drivers/i2c/s3c24x0_i2c.c: 2153 - activate this driver with CONFIG_SYS_I2C_S3C24X0 2154 - This driver adds i2c buses (11 for Exynos5250, Exynos5420 2155 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung) 2156 with a fix speed from 100000 and the slave addr 0! 2157 2158 - drivers/i2c/ihs_i2c.c 2159 - activate this driver with CONFIG_SYS_I2C_IHS 2160 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0 2161 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0 2162 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0 2163 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1 2164 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1 2165 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1 2166 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2 2167 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2 2168 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2 2169 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3 2170 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3 2171 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3 2172 - activate dual channel with CONFIG_SYS_I2C_IHS_DUAL 2173 - CONFIG_SYS_I2C_IHS_SPEED_0_1 speed channel 0_1 2174 - CONFIG_SYS_I2C_IHS_SLAVE_0_1 slave addr channel 0_1 2175 - CONFIG_SYS_I2C_IHS_SPEED_1_1 speed channel 1_1 2176 - CONFIG_SYS_I2C_IHS_SLAVE_1_1 slave addr channel 1_1 2177 - CONFIG_SYS_I2C_IHS_SPEED_2_1 speed channel 2_1 2178 - CONFIG_SYS_I2C_IHS_SLAVE_2_1 slave addr channel 2_1 2179 - CONFIG_SYS_I2C_IHS_SPEED_3_1 speed channel 3_1 2180 - CONFIG_SYS_I2C_IHS_SLAVE_3_1 slave addr channel 3_1 2181 2182 additional defines: 2183 2184 CONFIG_SYS_NUM_I2C_BUSES 2185 Hold the number of i2c buses you want to use. 2186 2187 CONFIG_SYS_I2C_DIRECT_BUS 2188 define this, if you don't use i2c muxes on your hardware. 2189 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can 2190 omit this define. 2191 2192 CONFIG_SYS_I2C_MAX_HOPS 2193 define how many muxes are maximal consecutively connected 2194 on one i2c bus. If you not use i2c muxes, omit this 2195 define. 2196 2197 CONFIG_SYS_I2C_BUSES 2198 hold a list of buses you want to use, only used if 2199 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example 2200 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and 2201 CONFIG_SYS_NUM_I2C_BUSES = 9: 2202 2203 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \ 2204 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \ 2205 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \ 2206 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \ 2207 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \ 2208 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \ 2209 {1, {I2C_NULL_HOP}}, \ 2210 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \ 2211 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \ 2212 } 2213 2214 which defines 2215 bus 0 on adapter 0 without a mux 2216 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1 2217 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2 2218 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3 2219 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4 2220 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5 2221 bus 6 on adapter 1 without a mux 2222 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1 2223 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2 2224 2225 If you do not have i2c muxes on your board, omit this define. 2226 2227- Legacy I2C Support: CONFIG_HARD_I2C 2228 2229 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which 2230 provides the following compelling advantages: 2231 2232 - more than one i2c adapter is usable 2233 - approved multibus support 2234 - better i2c mux support 2235 2236 ** Please consider updating your I2C driver now. ** 2237 2238 These enable legacy I2C serial bus commands. Defining 2239 CONFIG_HARD_I2C will include the appropriate I2C driver 2240 for the selected CPU. 2241 2242 This will allow you to use i2c commands at the u-boot 2243 command line (as long as you set CONFIG_CMD_I2C in 2244 CONFIG_COMMANDS) and communicate with i2c based realtime 2245 clock chips. See common/cmd_i2c.c for a description of the 2246 command line interface. 2247 2248 CONFIG_HARD_I2C selects a hardware I2C controller. 2249 2250 There are several other quantities that must also be 2251 defined when you define CONFIG_HARD_I2C. 2252 2253 In both cases you will need to define CONFIG_SYS_I2C_SPEED 2254 to be the frequency (in Hz) at which you wish your i2c bus 2255 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie 2256 the CPU's i2c node address). 2257 2258 Now, the u-boot i2c code for the mpc8xx 2259 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node 2260 and so its address should therefore be cleared to 0 (See, 2261 eg, MPC823e User's Manual p.16-473). So, set 2262 CONFIG_SYS_I2C_SLAVE to 0. 2263 2264 CONFIG_SYS_I2C_INIT_MPC5XXX 2265 2266 When a board is reset during an i2c bus transfer 2267 chips might think that the current transfer is still 2268 in progress. Reset the slave devices by sending start 2269 commands until the slave device responds. 2270 2271 That's all that's required for CONFIG_HARD_I2C. 2272 2273 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT) 2274 then the following macros need to be defined (examples are 2275 from include/configs/lwmon.h): 2276 2277 I2C_INIT 2278 2279 (Optional). Any commands necessary to enable the I2C 2280 controller or configure ports. 2281 2282 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 2283 2284 I2C_PORT 2285 2286 (Only for MPC8260 CPU). The I/O port to use (the code 2287 assumes both bits are on the same port). Valid values 2288 are 0..3 for ports A..D. 2289 2290 I2C_ACTIVE 2291 2292 The code necessary to make the I2C data line active 2293 (driven). If the data line is open collector, this 2294 define can be null. 2295 2296 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 2297 2298 I2C_TRISTATE 2299 2300 The code necessary to make the I2C data line tri-stated 2301 (inactive). If the data line is open collector, this 2302 define can be null. 2303 2304 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 2305 2306 I2C_READ 2307 2308 Code that returns true if the I2C data line is high, 2309 false if it is low. 2310 2311 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 2312 2313 I2C_SDA(bit) 2314 2315 If <bit> is true, sets the I2C data line high. If it 2316 is false, it clears it (low). 2317 2318 eg: #define I2C_SDA(bit) \ 2319 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 2320 else immr->im_cpm.cp_pbdat &= ~PB_SDA 2321 2322 I2C_SCL(bit) 2323 2324 If <bit> is true, sets the I2C clock line high. If it 2325 is false, it clears it (low). 2326 2327 eg: #define I2C_SCL(bit) \ 2328 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 2329 else immr->im_cpm.cp_pbdat &= ~PB_SCL 2330 2331 I2C_DELAY 2332 2333 This delay is invoked four times per clock cycle so this 2334 controls the rate of data transfer. The data rate thus 2335 is 1 / (I2C_DELAY * 4). Often defined to be something 2336 like: 2337 2338 #define I2C_DELAY udelay(2) 2339 2340 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 2341 2342 If your arch supports the generic GPIO framework (asm/gpio.h), 2343 then you may alternatively define the two GPIOs that are to be 2344 used as SCL / SDA. Any of the previous I2C_xxx macros will 2345 have GPIO-based defaults assigned to them as appropriate. 2346 2347 You should define these to the GPIO value as given directly to 2348 the generic GPIO functions. 2349 2350 CONFIG_SYS_I2C_INIT_BOARD 2351 2352 When a board is reset during an i2c bus transfer 2353 chips might think that the current transfer is still 2354 in progress. On some boards it is possible to access 2355 the i2c SCLK line directly, either by using the 2356 processor pin as a GPIO or by having a second pin 2357 connected to the bus. If this option is defined a 2358 custom i2c_init_board() routine in boards/xxx/board.c 2359 is run early in the boot sequence. 2360 2361 CONFIG_SYS_I2C_BOARD_LATE_INIT 2362 2363 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is 2364 defined a custom i2c_board_late_init() routine in 2365 boards/xxx/board.c is run AFTER the operations in i2c_init() 2366 is completed. This callpoint can be used to unreset i2c bus 2367 using CPU i2c controller register accesses for CPUs whose i2c 2368 controller provide such a method. It is called at the end of 2369 i2c_init() to allow i2c_init operations to setup the i2c bus 2370 controller on the CPU (e.g. setting bus speed & slave address). 2371 2372 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 2373 2374 This option enables configuration of bi_iic_fast[] flags 2375 in u-boot bd_info structure based on u-boot environment 2376 variable "i2cfast". (see also i2cfast) 2377 2378 CONFIG_I2C_MULTI_BUS 2379 2380 This option allows the use of multiple I2C buses, each of which 2381 must have a controller. At any point in time, only one bus is 2382 active. To switch to a different bus, use the 'i2c dev' command. 2383 Note that bus numbering is zero-based. 2384 2385 CONFIG_SYS_I2C_NOPROBES 2386 2387 This option specifies a list of I2C devices that will be skipped 2388 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 2389 is set, specify a list of bus-device pairs. Otherwise, specify 2390 a 1D array of device addresses 2391 2392 e.g. 2393 #undef CONFIG_I2C_MULTI_BUS 2394 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 2395 2396 will skip addresses 0x50 and 0x68 on a board with one I2C bus 2397 2398 #define CONFIG_I2C_MULTI_BUS 2399 #define CONFIG_SYS_I2C_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 2400 2401 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 2402 2403 CONFIG_SYS_SPD_BUS_NUM 2404 2405 If defined, then this indicates the I2C bus number for DDR SPD. 2406 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 2407 2408 CONFIG_SYS_RTC_BUS_NUM 2409 2410 If defined, then this indicates the I2C bus number for the RTC. 2411 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 2412 2413 CONFIG_SYS_DTT_BUS_NUM 2414 2415 If defined, then this indicates the I2C bus number for the DTT. 2416 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 2417 2418 CONFIG_SYS_I2C_DTT_ADDR: 2419 2420 If defined, specifies the I2C address of the DTT device. 2421 If not defined, then U-Boot uses predefined value for 2422 specified DTT device. 2423 2424 CONFIG_SOFT_I2C_READ_REPEATED_START 2425 2426 defining this will force the i2c_read() function in 2427 the soft_i2c driver to perform an I2C repeated start 2428 between writing the address pointer and reading the 2429 data. If this define is omitted the default behaviour 2430 of doing a stop-start sequence will be used. Most I2C 2431 devices can use either method, but some require one or 2432 the other. 2433 2434- SPI Support: CONFIG_SPI 2435 2436 Enables SPI driver (so far only tested with 2437 SPI EEPROM, also an instance works with Crystal A/D and 2438 D/As on the SACSng board) 2439 2440 CONFIG_SH_SPI 2441 2442 Enables the driver for SPI controller on SuperH. Currently 2443 only SH7757 is supported. 2444 2445 CONFIG_SOFT_SPI 2446 2447 Enables a software (bit-bang) SPI driver rather than 2448 using hardware support. This is a general purpose 2449 driver that only requires three general I/O port pins 2450 (two outputs, one input) to function. If this is 2451 defined, the board configuration must define several 2452 SPI configuration items (port pins to use, etc). For 2453 an example, see include/configs/sacsng.h. 2454 2455 CONFIG_HARD_SPI 2456 2457 Enables a hardware SPI driver for general-purpose reads 2458 and writes. As with CONFIG_SOFT_SPI, the board configuration 2459 must define a list of chip-select function pointers. 2460 Currently supported on some MPC8xxx processors. For an 2461 example, see include/configs/mpc8349emds.h. 2462 2463 CONFIG_MXC_SPI 2464 2465 Enables the driver for the SPI controllers on i.MX and MXC 2466 SoCs. Currently i.MX31/35/51 are supported. 2467 2468 CONFIG_SYS_SPI_MXC_WAIT 2469 Timeout for waiting until spi transfer completed. 2470 default: (CONFIG_SYS_HZ/100) /* 10 ms */ 2471 2472- FPGA Support: CONFIG_FPGA 2473 2474 Enables FPGA subsystem. 2475 2476 CONFIG_FPGA_<vendor> 2477 2478 Enables support for specific chip vendors. 2479 (ALTERA, XILINX) 2480 2481 CONFIG_FPGA_<family> 2482 2483 Enables support for FPGA family. 2484 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 2485 2486 CONFIG_FPGA_COUNT 2487 2488 Specify the number of FPGA devices to support. 2489 2490 CONFIG_CMD_FPGA_LOADMK 2491 2492 Enable support for fpga loadmk command 2493 2494 CONFIG_CMD_FPGA_LOADP 2495 2496 Enable support for fpga loadp command - load partial bitstream 2497 2498 CONFIG_CMD_FPGA_LOADBP 2499 2500 Enable support for fpga loadbp command - load partial bitstream 2501 (Xilinx only) 2502 2503 CONFIG_SYS_FPGA_PROG_FEEDBACK 2504 2505 Enable printing of hash marks during FPGA configuration. 2506 2507 CONFIG_SYS_FPGA_CHECK_BUSY 2508 2509 Enable checks on FPGA configuration interface busy 2510 status by the configuration function. This option 2511 will require a board or device specific function to 2512 be written. 2513 2514 CONFIG_FPGA_DELAY 2515 2516 If defined, a function that provides delays in the FPGA 2517 configuration driver. 2518 2519 CONFIG_SYS_FPGA_CHECK_CTRLC 2520 Allow Control-C to interrupt FPGA configuration 2521 2522 CONFIG_SYS_FPGA_CHECK_ERROR 2523 2524 Check for configuration errors during FPGA bitfile 2525 loading. For example, abort during Virtex II 2526 configuration if the INIT_B line goes low (which 2527 indicated a CRC error). 2528 2529 CONFIG_SYS_FPGA_WAIT_INIT 2530 2531 Maximum time to wait for the INIT_B line to de-assert 2532 after PROB_B has been de-asserted during a Virtex II 2533 FPGA configuration sequence. The default time is 500 2534 ms. 2535 2536 CONFIG_SYS_FPGA_WAIT_BUSY 2537 2538 Maximum time to wait for BUSY to de-assert during 2539 Virtex II FPGA configuration. The default is 5 ms. 2540 2541 CONFIG_SYS_FPGA_WAIT_CONFIG 2542 2543 Time to wait after FPGA configuration. The default is 2544 200 ms. 2545 2546- Configuration Management: 2547 CONFIG_BUILD_TARGET 2548 2549 Some SoCs need special image types (e.g. U-Boot binary 2550 with a special header) as build targets. By defining 2551 CONFIG_BUILD_TARGET in the SoC / board header, this 2552 special image will be automatically built upon calling 2553 make / buildman. 2554 2555 CONFIG_IDENT_STRING 2556 2557 If defined, this string will be added to the U-Boot 2558 version information (U_BOOT_VERSION) 2559 2560- Vendor Parameter Protection: 2561 2562 U-Boot considers the values of the environment 2563 variables "serial#" (Board Serial Number) and 2564 "ethaddr" (Ethernet Address) to be parameters that 2565 are set once by the board vendor / manufacturer, and 2566 protects these variables from casual modification by 2567 the user. Once set, these variables are read-only, 2568 and write or delete attempts are rejected. You can 2569 change this behaviour: 2570 2571 If CONFIG_ENV_OVERWRITE is #defined in your config 2572 file, the write protection for vendor parameters is 2573 completely disabled. Anybody can change or delete 2574 these parameters. 2575 2576 Alternatively, if you define _both_ an ethaddr in the 2577 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2578 Ethernet address is installed in the environment, 2579 which can be changed exactly ONCE by the user. [The 2580 serial# is unaffected by this, i. e. it remains 2581 read-only.] 2582 2583 The same can be accomplished in a more flexible way 2584 for any variable by configuring the type of access 2585 to allow for those variables in the ".flags" variable 2586 or define CONFIG_ENV_FLAGS_LIST_STATIC. 2587 2588- Protected RAM: 2589 CONFIG_PRAM 2590 2591 Define this variable to enable the reservation of 2592 "protected RAM", i. e. RAM which is not overwritten 2593 by U-Boot. Define CONFIG_PRAM to hold the number of 2594 kB you want to reserve for pRAM. You can overwrite 2595 this default value by defining an environment 2596 variable "pram" to the number of kB you want to 2597 reserve. Note that the board info structure will 2598 still show the full amount of RAM. If pRAM is 2599 reserved, a new environment variable "mem" will 2600 automatically be defined to hold the amount of 2601 remaining RAM in a form that can be passed as boot 2602 argument to Linux, for instance like that: 2603 2604 setenv bootargs ... mem=\${mem} 2605 saveenv 2606 2607 This way you can tell Linux not to use this memory, 2608 either, which results in a memory region that will 2609 not be affected by reboots. 2610 2611 *WARNING* If your board configuration uses automatic 2612 detection of the RAM size, you must make sure that 2613 this memory test is non-destructive. So far, the 2614 following board configurations are known to be 2615 "pRAM-clean": 2616 2617 IVMS8, IVML24, SPD8xx, TQM8xxL, 2618 HERMES, IP860, RPXlite, LWMON, 2619 FLAGADM, TQM8260 2620 2621- Access to physical memory region (> 4GB) 2622 Some basic support is provided for operations on memory not 2623 normally accessible to U-Boot - e.g. some architectures 2624 support access to more than 4GB of memory on 32-bit 2625 machines using physical address extension or similar. 2626 Define CONFIG_PHYSMEM to access this basic support, which 2627 currently only supports clearing the memory. 2628 2629- Error Recovery: 2630 CONFIG_PANIC_HANG 2631 2632 Define this variable to stop the system in case of a 2633 fatal error, so that you have to reset it manually. 2634 This is probably NOT a good idea for an embedded 2635 system where you want the system to reboot 2636 automatically as fast as possible, but it may be 2637 useful during development since you can try to debug 2638 the conditions that lead to the situation. 2639 2640 CONFIG_NET_RETRY_COUNT 2641 2642 This variable defines the number of retries for 2643 network operations like ARP, RARP, TFTP, or BOOTP 2644 before giving up the operation. If not defined, a 2645 default value of 5 is used. 2646 2647 CONFIG_ARP_TIMEOUT 2648 2649 Timeout waiting for an ARP reply in milliseconds. 2650 2651 CONFIG_NFS_TIMEOUT 2652 2653 Timeout in milliseconds used in NFS protocol. 2654 If you encounter "ERROR: Cannot umount" in nfs command, 2655 try longer timeout such as 2656 #define CONFIG_NFS_TIMEOUT 10000UL 2657 2658- Command Interpreter: 2659 CONFIG_AUTO_COMPLETE 2660 2661 Enable auto completion of commands using TAB. 2662 2663 CONFIG_SYS_PROMPT_HUSH_PS2 2664 2665 This defines the secondary prompt string, which is 2666 printed when the command interpreter needs more input 2667 to complete a command. Usually "> ". 2668 2669 Note: 2670 2671 In the current implementation, the local variables 2672 space and global environment variables space are 2673 separated. Local variables are those you define by 2674 simply typing `name=value'. To access a local 2675 variable later on, you have write `$name' or 2676 `${name}'; to execute the contents of a variable 2677 directly type `$name' at the command prompt. 2678 2679 Global environment variables are those you use 2680 setenv/printenv to work with. To run a command stored 2681 in such a variable, you need to use the run command, 2682 and you must not use the '$' sign to access them. 2683 2684 To store commands and special characters in a 2685 variable, please use double quotation marks 2686 surrounding the whole text of the variable, instead 2687 of the backslashes before semicolons and special 2688 symbols. 2689 2690- Command Line Editing and History: 2691 CONFIG_CMDLINE_EDITING 2692 2693 Enable editing and History functions for interactive 2694 command line input operations 2695 2696- Command Line PS1/PS2 support: 2697 CONFIG_CMDLINE_PS_SUPPORT 2698 2699 Enable support for changing the command prompt string 2700 at run-time. Only static string is supported so far. 2701 The string is obtained from environment variables PS1 2702 and PS2. 2703 2704- Default Environment: 2705 CONFIG_EXTRA_ENV_SETTINGS 2706 2707 Define this to contain any number of null terminated 2708 strings (variable = value pairs) that will be part of 2709 the default environment compiled into the boot image. 2710 2711 For example, place something like this in your 2712 board's config file: 2713 2714 #define CONFIG_EXTRA_ENV_SETTINGS \ 2715 "myvar1=value1\0" \ 2716 "myvar2=value2\0" 2717 2718 Warning: This method is based on knowledge about the 2719 internal format how the environment is stored by the 2720 U-Boot code. This is NOT an official, exported 2721 interface! Although it is unlikely that this format 2722 will change soon, there is no guarantee either. 2723 You better know what you are doing here. 2724 2725 Note: overly (ab)use of the default environment is 2726 discouraged. Make sure to check other ways to preset 2727 the environment like the "source" command or the 2728 boot command first. 2729 2730 CONFIG_ENV_VARS_UBOOT_CONFIG 2731 2732 Define this in order to add variables describing the 2733 U-Boot build configuration to the default environment. 2734 These will be named arch, cpu, board, vendor, and soc. 2735 2736 Enabling this option will cause the following to be defined: 2737 2738 - CONFIG_SYS_ARCH 2739 - CONFIG_SYS_CPU 2740 - CONFIG_SYS_BOARD 2741 - CONFIG_SYS_VENDOR 2742 - CONFIG_SYS_SOC 2743 2744 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG 2745 2746 Define this in order to add variables describing certain 2747 run-time determined information about the hardware to the 2748 environment. These will be named board_name, board_rev. 2749 2750 CONFIG_DELAY_ENVIRONMENT 2751 2752 Normally the environment is loaded when the board is 2753 initialised so that it is available to U-Boot. This inhibits 2754 that so that the environment is not available until 2755 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL 2756 this is instead controlled by the value of 2757 /config/load-environment. 2758 2759- DataFlash Support: 2760 CONFIG_HAS_DATAFLASH 2761 2762 Defining this option enables DataFlash features and 2763 allows to read/write in Dataflash via the standard 2764 commands cp, md... 2765 2766- Serial Flash support 2767 CONFIG_CMD_SF 2768 2769 Defining this option enables SPI flash commands 2770 'sf probe/read/write/erase/update'. 2771 2772 Usage requires an initial 'probe' to define the serial 2773 flash parameters, followed by read/write/erase/update 2774 commands. 2775 2776 The following defaults may be provided by the platform 2777 to handle the common case when only a single serial 2778 flash is present on the system. 2779 2780 CONFIG_SF_DEFAULT_BUS Bus identifier 2781 CONFIG_SF_DEFAULT_CS Chip-select 2782 CONFIG_SF_DEFAULT_MODE (see include/spi.h) 2783 CONFIG_SF_DEFAULT_SPEED in Hz 2784 2785 CONFIG_CMD_SF_TEST 2786 2787 Define this option to include a destructive SPI flash 2788 test ('sf test'). 2789 2790 CONFIG_SF_DUAL_FLASH Dual flash memories 2791 2792 Define this option to use dual flash support where two flash 2793 memories can be connected with a given cs line. 2794 Currently Xilinx Zynq qspi supports these type of connections. 2795 2796- SystemACE Support: 2797 CONFIG_SYSTEMACE 2798 2799 Adding this option adds support for Xilinx SystemACE 2800 chips attached via some sort of local bus. The address 2801 of the chip must also be defined in the 2802 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 2803 2804 #define CONFIG_SYSTEMACE 2805 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 2806 2807 When SystemACE support is added, the "ace" device type 2808 becomes available to the fat commands, i.e. fatls. 2809 2810- TFTP Fixed UDP Port: 2811 CONFIG_TFTP_PORT 2812 2813 If this is defined, the environment variable tftpsrcp 2814 is used to supply the TFTP UDP source port value. 2815 If tftpsrcp isn't defined, the normal pseudo-random port 2816 number generator is used. 2817 2818 Also, the environment variable tftpdstp is used to supply 2819 the TFTP UDP destination port value. If tftpdstp isn't 2820 defined, the normal port 69 is used. 2821 2822 The purpose for tftpsrcp is to allow a TFTP server to 2823 blindly start the TFTP transfer using the pre-configured 2824 target IP address and UDP port. This has the effect of 2825 "punching through" the (Windows XP) firewall, allowing 2826 the remainder of the TFTP transfer to proceed normally. 2827 A better solution is to properly configure the firewall, 2828 but sometimes that is not allowed. 2829 2830- Hashing support: 2831 CONFIG_CMD_HASH 2832 2833 This enables a generic 'hash' command which can produce 2834 hashes / digests from a few algorithms (e.g. SHA1, SHA256). 2835 2836 CONFIG_HASH_VERIFY 2837 2838 Enable the hash verify command (hash -v). This adds to code 2839 size a little. 2840 2841 CONFIG_SHA1 - This option enables support of hashing using SHA1 2842 algorithm. The hash is calculated in software. 2843 CONFIG_SHA256 - This option enables support of hashing using 2844 SHA256 algorithm. The hash is calculated in software. 2845 CONFIG_SHA_HW_ACCEL - This option enables hardware acceleration 2846 for SHA1/SHA256 hashing. 2847 This affects the 'hash' command and also the 2848 hash_lookup_algo() function. 2849 CONFIG_SHA_PROG_HW_ACCEL - This option enables 2850 hardware-acceleration for SHA1/SHA256 progressive hashing. 2851 Data can be streamed in a block at a time and the hashing 2852 is performed in hardware. 2853 2854 Note: There is also a sha1sum command, which should perhaps 2855 be deprecated in favour of 'hash sha1'. 2856 2857- Freescale i.MX specific commands: 2858 CONFIG_CMD_HDMIDETECT 2859 This enables 'hdmidet' command which returns true if an 2860 HDMI monitor is detected. This command is i.MX 6 specific. 2861 2862 CONFIG_CMD_BMODE 2863 This enables the 'bmode' (bootmode) command for forcing 2864 a boot from specific media. 2865 2866 This is useful for forcing the ROM's usb downloader to 2867 activate upon a watchdog reset which is nice when iterating 2868 on U-Boot. Using the reset button or running bmode normal 2869 will set it back to normal. This command currently 2870 supports i.MX53 and i.MX6. 2871 2872- bootcount support: 2873 CONFIG_BOOTCOUNT_LIMIT 2874 2875 This enables the bootcounter support, see: 2876 http://www.denx.de/wiki/DULG/UBootBootCountLimit 2877 2878 CONFIG_AT91SAM9XE 2879 enable special bootcounter support on at91sam9xe based boards. 2880 CONFIG_BLACKFIN 2881 enable special bootcounter support on blackfin based boards. 2882 CONFIG_SOC_DA8XX 2883 enable special bootcounter support on da850 based boards. 2884 CONFIG_BOOTCOUNT_RAM 2885 enable support for the bootcounter in RAM 2886 CONFIG_BOOTCOUNT_I2C 2887 enable support for the bootcounter on an i2c (like RTC) device. 2888 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address 2889 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for 2890 the bootcounter. 2891 CONFIG_BOOTCOUNT_ALEN = address len 2892 2893- Show boot progress: 2894 CONFIG_SHOW_BOOT_PROGRESS 2895 2896 Defining this option allows to add some board- 2897 specific code (calling a user-provided function 2898 "show_boot_progress(int)") that enables you to show 2899 the system's boot progress on some display (for 2900 example, some LED's) on your board. At the moment, 2901 the following checkpoints are implemented: 2902 2903 2904Legacy uImage format: 2905 2906 Arg Where When 2907 1 common/cmd_bootm.c before attempting to boot an image 2908 -1 common/cmd_bootm.c Image header has bad magic number 2909 2 common/cmd_bootm.c Image header has correct magic number 2910 -2 common/cmd_bootm.c Image header has bad checksum 2911 3 common/cmd_bootm.c Image header has correct checksum 2912 -3 common/cmd_bootm.c Image data has bad checksum 2913 4 common/cmd_bootm.c Image data has correct checksum 2914 -4 common/cmd_bootm.c Image is for unsupported architecture 2915 5 common/cmd_bootm.c Architecture check OK 2916 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 2917 6 common/cmd_bootm.c Image Type check OK 2918 -6 common/cmd_bootm.c gunzip uncompression error 2919 -7 common/cmd_bootm.c Unimplemented compression type 2920 7 common/cmd_bootm.c Uncompression OK 2921 8 common/cmd_bootm.c No uncompress/copy overwrite error 2922 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 2923 2924 9 common/image.c Start initial ramdisk verification 2925 -10 common/image.c Ramdisk header has bad magic number 2926 -11 common/image.c Ramdisk header has bad checksum 2927 10 common/image.c Ramdisk header is OK 2928 -12 common/image.c Ramdisk data has bad checksum 2929 11 common/image.c Ramdisk data has correct checksum 2930 12 common/image.c Ramdisk verification complete, start loading 2931 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 2932 13 common/image.c Start multifile image verification 2933 14 common/image.c No initial ramdisk, no multifile, continue. 2934 2935 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 2936 2937 -30 arch/powerpc/lib/board.c Fatal error, hang the system 2938 -31 post/post.c POST test failed, detected by post_output_backlog() 2939 -32 post/post.c POST test failed, detected by post_run_single() 2940 2941 34 common/cmd_doc.c before loading a Image from a DOC device 2942 -35 common/cmd_doc.c Bad usage of "doc" command 2943 35 common/cmd_doc.c correct usage of "doc" command 2944 -36 common/cmd_doc.c No boot device 2945 36 common/cmd_doc.c correct boot device 2946 -37 common/cmd_doc.c Unknown Chip ID on boot device 2947 37 common/cmd_doc.c correct chip ID found, device available 2948 -38 common/cmd_doc.c Read Error on boot device 2949 38 common/cmd_doc.c reading Image header from DOC device OK 2950 -39 common/cmd_doc.c Image header has bad magic number 2951 39 common/cmd_doc.c Image header has correct magic number 2952 -40 common/cmd_doc.c Error reading Image from DOC device 2953 40 common/cmd_doc.c Image header has correct magic number 2954 41 common/cmd_ide.c before loading a Image from a IDE device 2955 -42 common/cmd_ide.c Bad usage of "ide" command 2956 42 common/cmd_ide.c correct usage of "ide" command 2957 -43 common/cmd_ide.c No boot device 2958 43 common/cmd_ide.c boot device found 2959 -44 common/cmd_ide.c Device not available 2960 44 common/cmd_ide.c Device available 2961 -45 common/cmd_ide.c wrong partition selected 2962 45 common/cmd_ide.c partition selected 2963 -46 common/cmd_ide.c Unknown partition table 2964 46 common/cmd_ide.c valid partition table found 2965 -47 common/cmd_ide.c Invalid partition type 2966 47 common/cmd_ide.c correct partition type 2967 -48 common/cmd_ide.c Error reading Image Header on boot device 2968 48 common/cmd_ide.c reading Image Header from IDE device OK 2969 -49 common/cmd_ide.c Image header has bad magic number 2970 49 common/cmd_ide.c Image header has correct magic number 2971 -50 common/cmd_ide.c Image header has bad checksum 2972 50 common/cmd_ide.c Image header has correct checksum 2973 -51 common/cmd_ide.c Error reading Image from IDE device 2974 51 common/cmd_ide.c reading Image from IDE device OK 2975 52 common/cmd_nand.c before loading a Image from a NAND device 2976 -53 common/cmd_nand.c Bad usage of "nand" command 2977 53 common/cmd_nand.c correct usage of "nand" command 2978 -54 common/cmd_nand.c No boot device 2979 54 common/cmd_nand.c boot device found 2980 -55 common/cmd_nand.c Unknown Chip ID on boot device 2981 55 common/cmd_nand.c correct chip ID found, device available 2982 -56 common/cmd_nand.c Error reading Image Header on boot device 2983 56 common/cmd_nand.c reading Image Header from NAND device OK 2984 -57 common/cmd_nand.c Image header has bad magic number 2985 57 common/cmd_nand.c Image header has correct magic number 2986 -58 common/cmd_nand.c Error reading Image from NAND device 2987 58 common/cmd_nand.c reading Image from NAND device OK 2988 2989 -60 common/env_common.c Environment has a bad CRC, using default 2990 2991 64 net/eth.c starting with Ethernet configuration. 2992 -64 net/eth.c no Ethernet found. 2993 65 net/eth.c Ethernet found. 2994 2995 -80 common/cmd_net.c usage wrong 2996 80 common/cmd_net.c before calling net_loop() 2997 -81 common/cmd_net.c some error in net_loop() occurred 2998 81 common/cmd_net.c net_loop() back without error 2999 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 3000 82 common/cmd_net.c trying automatic boot 3001 83 common/cmd_net.c running "source" command 3002 -83 common/cmd_net.c some error in automatic boot or "source" command 3003 84 common/cmd_net.c end without errors 3004 3005FIT uImage format: 3006 3007 Arg Where When 3008 100 common/cmd_bootm.c Kernel FIT Image has correct format 3009 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 3010 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 3011 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 3012 102 common/cmd_bootm.c Kernel unit name specified 3013 -103 common/cmd_bootm.c Can't get kernel subimage node offset 3014 103 common/cmd_bootm.c Found configuration node 3015 104 common/cmd_bootm.c Got kernel subimage node offset 3016 -104 common/cmd_bootm.c Kernel subimage hash verification failed 3017 105 common/cmd_bootm.c Kernel subimage hash verification OK 3018 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 3019 106 common/cmd_bootm.c Architecture check OK 3020 -106 common/cmd_bootm.c Kernel subimage has wrong type 3021 107 common/cmd_bootm.c Kernel subimage type OK 3022 -107 common/cmd_bootm.c Can't get kernel subimage data/size 3023 108 common/cmd_bootm.c Got kernel subimage data/size 3024 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 3025 -109 common/cmd_bootm.c Can't get kernel subimage type 3026 -110 common/cmd_bootm.c Can't get kernel subimage comp 3027 -111 common/cmd_bootm.c Can't get kernel subimage os 3028 -112 common/cmd_bootm.c Can't get kernel subimage load address 3029 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 3030 3031 120 common/image.c Start initial ramdisk verification 3032 -120 common/image.c Ramdisk FIT image has incorrect format 3033 121 common/image.c Ramdisk FIT image has correct format 3034 122 common/image.c No ramdisk subimage unit name, using configuration 3035 -122 common/image.c Can't get configuration for ramdisk subimage 3036 123 common/image.c Ramdisk unit name specified 3037 -124 common/image.c Can't get ramdisk subimage node offset 3038 125 common/image.c Got ramdisk subimage node offset 3039 -125 common/image.c Ramdisk subimage hash verification failed 3040 126 common/image.c Ramdisk subimage hash verification OK 3041 -126 common/image.c Ramdisk subimage for unsupported architecture 3042 127 common/image.c Architecture check OK 3043 -127 common/image.c Can't get ramdisk subimage data/size 3044 128 common/image.c Got ramdisk subimage data/size 3045 129 common/image.c Can't get ramdisk load address 3046 -129 common/image.c Got ramdisk load address 3047 3048 -130 common/cmd_doc.c Incorrect FIT image format 3049 131 common/cmd_doc.c FIT image format OK 3050 3051 -140 common/cmd_ide.c Incorrect FIT image format 3052 141 common/cmd_ide.c FIT image format OK 3053 3054 -150 common/cmd_nand.c Incorrect FIT image format 3055 151 common/cmd_nand.c FIT image format OK 3056 3057- legacy image format: 3058 CONFIG_IMAGE_FORMAT_LEGACY 3059 enables the legacy image format support in U-Boot. 3060 3061 Default: 3062 enabled if CONFIG_FIT_SIGNATURE is not defined. 3063 3064 CONFIG_DISABLE_IMAGE_LEGACY 3065 disable the legacy image format 3066 3067 This define is introduced, as the legacy image format is 3068 enabled per default for backward compatibility. 3069 3070- FIT image support: 3071 CONFIG_FIT_DISABLE_SHA256 3072 Supporting SHA256 hashes has quite an impact on binary size. 3073 For constrained systems sha256 hash support can be disabled 3074 with this option. 3075 3076 TODO(sjg@chromium.org): Adjust this option to be positive, 3077 and move it to Kconfig 3078 3079- Standalone program support: 3080 CONFIG_STANDALONE_LOAD_ADDR 3081 3082 This option defines a board specific value for the 3083 address where standalone program gets loaded, thus 3084 overwriting the architecture dependent default 3085 settings. 3086 3087- Frame Buffer Address: 3088 CONFIG_FB_ADDR 3089 3090 Define CONFIG_FB_ADDR if you want to use specific 3091 address for frame buffer. This is typically the case 3092 when using a graphics controller has separate video 3093 memory. U-Boot will then place the frame buffer at 3094 the given address instead of dynamically reserving it 3095 in system RAM by calling lcd_setmem(), which grabs 3096 the memory for the frame buffer depending on the 3097 configured panel size. 3098 3099 Please see board_init_f function. 3100 3101- Automatic software updates via TFTP server 3102 CONFIG_UPDATE_TFTP 3103 CONFIG_UPDATE_TFTP_CNT_MAX 3104 CONFIG_UPDATE_TFTP_MSEC_MAX 3105 3106 These options enable and control the auto-update feature; 3107 for a more detailed description refer to doc/README.update. 3108 3109- MTD Support (mtdparts command, UBI support) 3110 CONFIG_MTD_DEVICE 3111 3112 Adds the MTD device infrastructure from the Linux kernel. 3113 Needed for mtdparts command support. 3114 3115 CONFIG_MTD_PARTITIONS 3116 3117 Adds the MTD partitioning infrastructure from the Linux 3118 kernel. Needed for UBI support. 3119 3120- UBI support 3121 CONFIG_CMD_UBI 3122 3123 Adds commands for interacting with MTD partitions formatted 3124 with the UBI flash translation layer 3125 3126 Requires also defining CONFIG_RBTREE 3127 3128 CONFIG_UBI_SILENCE_MSG 3129 3130 Make the verbose messages from UBI stop printing. This leaves 3131 warnings and errors enabled. 3132 3133 3134 CONFIG_MTD_UBI_WL_THRESHOLD 3135 This parameter defines the maximum difference between the highest 3136 erase counter value and the lowest erase counter value of eraseblocks 3137 of UBI devices. When this threshold is exceeded, UBI starts performing 3138 wear leveling by means of moving data from eraseblock with low erase 3139 counter to eraseblocks with high erase counter. 3140 3141 The default value should be OK for SLC NAND flashes, NOR flashes and 3142 other flashes which have eraseblock life-cycle 100000 or more. 3143 However, in case of MLC NAND flashes which typically have eraseblock 3144 life-cycle less than 10000, the threshold should be lessened (e.g., 3145 to 128 or 256, although it does not have to be power of 2). 3146 3147 default: 4096 3148 3149 CONFIG_MTD_UBI_BEB_LIMIT 3150 This option specifies the maximum bad physical eraseblocks UBI 3151 expects on the MTD device (per 1024 eraseblocks). If the 3152 underlying flash does not admit of bad eraseblocks (e.g. NOR 3153 flash), this value is ignored. 3154 3155 NAND datasheets often specify the minimum and maximum NVM 3156 (Number of Valid Blocks) for the flashes' endurance lifetime. 3157 The maximum expected bad eraseblocks per 1024 eraseblocks 3158 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)", 3159 which gives 20 for most NANDs (MaxNVB is basically the total 3160 count of eraseblocks on the chip). 3161 3162 To put it differently, if this value is 20, UBI will try to 3163 reserve about 1.9% of physical eraseblocks for bad blocks 3164 handling. And that will be 1.9% of eraseblocks on the entire 3165 NAND chip, not just the MTD partition UBI attaches. This means 3166 that if you have, say, a NAND flash chip admits maximum 40 bad 3167 eraseblocks, and it is split on two MTD partitions of the same 3168 size, UBI will reserve 40 eraseblocks when attaching a 3169 partition. 3170 3171 default: 20 3172 3173 CONFIG_MTD_UBI_FASTMAP 3174 Fastmap is a mechanism which allows attaching an UBI device 3175 in nearly constant time. Instead of scanning the whole MTD device it 3176 only has to locate a checkpoint (called fastmap) on the device. 3177 The on-flash fastmap contains all information needed to attach 3178 the device. Using fastmap makes only sense on large devices where 3179 attaching by scanning takes long. UBI will not automatically install 3180 a fastmap on old images, but you can set the UBI parameter 3181 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note 3182 that fastmap-enabled images are still usable with UBI implementations 3183 without fastmap support. On typical flash devices the whole fastmap 3184 fits into one PEB. UBI will reserve PEBs to hold two fastmaps. 3185 3186 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT 3187 Set this parameter to enable fastmap automatically on images 3188 without a fastmap. 3189 default: 0 3190 3191 CONFIG_MTD_UBI_FM_DEBUG 3192 Enable UBI fastmap debug 3193 default: 0 3194 3195- UBIFS support 3196 CONFIG_CMD_UBIFS 3197 3198 Adds commands for interacting with UBI volumes formatted as 3199 UBIFS. UBIFS is read-only in u-boot. 3200 3201 Requires UBI support as well as CONFIG_LZO 3202 3203 CONFIG_UBIFS_SILENCE_MSG 3204 3205 Make the verbose messages from UBIFS stop printing. This leaves 3206 warnings and errors enabled. 3207 3208- SPL framework 3209 CONFIG_SPL 3210 Enable building of SPL globally. 3211 3212 CONFIG_SPL_LDSCRIPT 3213 LDSCRIPT for linking the SPL binary. 3214 3215 CONFIG_SPL_MAX_FOOTPRINT 3216 Maximum size in memory allocated to the SPL, BSS included. 3217 When defined, the linker checks that the actual memory 3218 used by SPL from _start to __bss_end does not exceed it. 3219 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3220 must not be both defined at the same time. 3221 3222 CONFIG_SPL_MAX_SIZE 3223 Maximum size of the SPL image (text, data, rodata, and 3224 linker lists sections), BSS excluded. 3225 When defined, the linker checks that the actual size does 3226 not exceed it. 3227 3228 CONFIG_SPL_TEXT_BASE 3229 TEXT_BASE for linking the SPL binary. 3230 3231 CONFIG_SPL_RELOC_TEXT_BASE 3232 Address to relocate to. If unspecified, this is equal to 3233 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done). 3234 3235 CONFIG_SPL_BSS_START_ADDR 3236 Link address for the BSS within the SPL binary. 3237 3238 CONFIG_SPL_BSS_MAX_SIZE 3239 Maximum size in memory allocated to the SPL BSS. 3240 When defined, the linker checks that the actual memory used 3241 by SPL from __bss_start to __bss_end does not exceed it. 3242 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3243 must not be both defined at the same time. 3244 3245 CONFIG_SPL_STACK 3246 Adress of the start of the stack SPL will use 3247 3248 CONFIG_SPL_PANIC_ON_RAW_IMAGE 3249 When defined, SPL will panic() if the image it has 3250 loaded does not have a signature. 3251 Defining this is useful when code which loads images 3252 in SPL cannot guarantee that absolutely all read errors 3253 will be caught. 3254 An example is the LPC32XX MLC NAND driver, which will 3255 consider that a completely unreadable NAND block is bad, 3256 and thus should be skipped silently. 3257 3258 CONFIG_SPL_ABORT_ON_RAW_IMAGE 3259 When defined, SPL will proceed to another boot method 3260 if the image it has loaded does not have a signature. 3261 3262 CONFIG_SPL_RELOC_STACK 3263 Adress of the start of the stack SPL will use after 3264 relocation. If unspecified, this is equal to 3265 CONFIG_SPL_STACK. 3266 3267 CONFIG_SYS_SPL_MALLOC_START 3268 Starting address of the malloc pool used in SPL. 3269 When this option is set the full malloc is used in SPL and 3270 it is set up by spl_init() and before that, the simple malloc() 3271 can be used if CONFIG_SYS_MALLOC_F is defined. 3272 3273 CONFIG_SYS_SPL_MALLOC_SIZE 3274 The size of the malloc pool used in SPL. 3275 3276 CONFIG_SPL_FRAMEWORK 3277 Enable the SPL framework under common/. This framework 3278 supports MMC, NAND and YMODEM loading of U-Boot and NAND 3279 NAND loading of the Linux Kernel. 3280 3281 CONFIG_SPL_OS_BOOT 3282 Enable booting directly to an OS from SPL. 3283 See also: doc/README.falcon 3284 3285 CONFIG_SPL_DISPLAY_PRINT 3286 For ARM, enable an optional function to print more information 3287 about the running system. 3288 3289 CONFIG_SPL_INIT_MINIMAL 3290 Arch init code should be built for a very small image 3291 3292 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION 3293 Partition on the MMC to load U-Boot from when the MMC is being 3294 used in raw mode 3295 3296 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR 3297 Sector to load kernel uImage from when MMC is being 3298 used in raw mode (for Falcon mode) 3299 3300 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR, 3301 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS 3302 Sector and number of sectors to load kernel argument 3303 parameters from when MMC is being used in raw mode 3304 (for falcon mode) 3305 3306 CONFIG_SYS_MMCSD_FS_BOOT_PARTITION 3307 Partition on the MMC to load U-Boot from when the MMC is being 3308 used in fs mode 3309 3310 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME 3311 Filename to read to load U-Boot when reading from filesystem 3312 3313 CONFIG_SPL_FS_LOAD_KERNEL_NAME 3314 Filename to read to load kernel uImage when reading 3315 from filesystem (for Falcon mode) 3316 3317 CONFIG_SPL_FS_LOAD_ARGS_NAME 3318 Filename to read to load kernel argument parameters 3319 when reading from filesystem (for Falcon mode) 3320 3321 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND 3322 Set this for NAND SPL on PPC mpc83xx targets, so that 3323 start.S waits for the rest of the SPL to load before 3324 continuing (the hardware starts execution after just 3325 loading the first page rather than the full 4K). 3326 3327 CONFIG_SPL_SKIP_RELOCATE 3328 Avoid SPL relocation 3329 3330 CONFIG_SPL_NAND_BASE 3331 Include nand_base.c in the SPL. Requires 3332 CONFIG_SPL_NAND_DRIVERS. 3333 3334 CONFIG_SPL_NAND_DRIVERS 3335 SPL uses normal NAND drivers, not minimal drivers. 3336 3337 CONFIG_SPL_NAND_ECC 3338 Include standard software ECC in the SPL 3339 3340 CONFIG_SPL_NAND_SIMPLE 3341 Support for NAND boot using simple NAND drivers that 3342 expose the cmd_ctrl() interface. 3343 3344 CONFIG_SPL_UBI 3345 Support for a lightweight UBI (fastmap) scanner and 3346 loader 3347 3348 CONFIG_SPL_NAND_RAW_ONLY 3349 Support to boot only raw u-boot.bin images. Use this only 3350 if you need to save space. 3351 3352 CONFIG_SPL_COMMON_INIT_DDR 3353 Set for common ddr init with serial presence detect in 3354 SPL binary. 3355 3356 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT, 3357 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE, 3358 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS, 3359 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE, 3360 CONFIG_SYS_NAND_ECCBYTES 3361 Defines the size and behavior of the NAND that SPL uses 3362 to read U-Boot 3363 3364 CONFIG_SPL_NAND_BOOT 3365 Add support NAND boot 3366 3367 CONFIG_SYS_NAND_U_BOOT_OFFS 3368 Location in NAND to read U-Boot from 3369 3370 CONFIG_SYS_NAND_U_BOOT_DST 3371 Location in memory to load U-Boot to 3372 3373 CONFIG_SYS_NAND_U_BOOT_SIZE 3374 Size of image to load 3375 3376 CONFIG_SYS_NAND_U_BOOT_START 3377 Entry point in loaded image to jump to 3378 3379 CONFIG_SYS_NAND_HW_ECC_OOBFIRST 3380 Define this if you need to first read the OOB and then the 3381 data. This is used, for example, on davinci platforms. 3382 3383 CONFIG_SPL_OMAP3_ID_NAND 3384 Support for an OMAP3-specific set of functions to return the 3385 ID and MFR of the first attached NAND chip, if present. 3386 3387 CONFIG_SPL_RAM_DEVICE 3388 Support for running image already present in ram, in SPL binary 3389 3390 CONFIG_SPL_PAD_TO 3391 Image offset to which the SPL should be padded before appending 3392 the SPL payload. By default, this is defined as 3393 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3394 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3395 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3396 3397 CONFIG_SPL_TARGET 3398 Final target image containing SPL and payload. Some SPLs 3399 use an arch-specific makefile fragment instead, for 3400 example if more than one image needs to be produced. 3401 3402 CONFIG_FIT_SPL_PRINT 3403 Printing information about a FIT image adds quite a bit of 3404 code to SPL. So this is normally disabled in SPL. Use this 3405 option to re-enable it. This will affect the output of the 3406 bootm command when booting a FIT image. 3407 3408- TPL framework 3409 CONFIG_TPL 3410 Enable building of TPL globally. 3411 3412 CONFIG_TPL_PAD_TO 3413 Image offset to which the TPL should be padded before appending 3414 the TPL payload. By default, this is defined as 3415 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3416 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3417 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3418 3419- Interrupt support (PPC): 3420 3421 There are common interrupt_init() and timer_interrupt() 3422 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 3423 for CPU specific initialization. interrupt_init_cpu() 3424 should set decrementer_count to appropriate value. If 3425 CPU resets decrementer automatically after interrupt 3426 (ppc4xx) it should set decrementer_count to zero. 3427 timer_interrupt() calls timer_interrupt_cpu() for CPU 3428 specific handling. If board has watchdog / status_led 3429 / other_activity_monitor it works automatically from 3430 general timer_interrupt(). 3431 3432 3433Board initialization settings: 3434------------------------------ 3435 3436During Initialization u-boot calls a number of board specific functions 3437to allow the preparation of board specific prerequisites, e.g. pin setup 3438before drivers are initialized. To enable these callbacks the 3439following configuration macros have to be defined. Currently this is 3440architecture specific, so please check arch/your_architecture/lib/board.c 3441typically in board_init_f() and board_init_r(). 3442 3443- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 3444- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 3445- CONFIG_BOARD_LATE_INIT: Call board_late_init() 3446- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 3447 3448Configuration Settings: 3449----------------------- 3450 3451- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit. 3452 Optionally it can be defined to support 64-bit memory commands. 3453 3454- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 3455 undefine this when you're short of memory. 3456 3457- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 3458 width of the commands listed in the 'help' command output. 3459 3460- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 3461 prompt for user input. 3462 3463- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 3464 3465- CONFIG_SYS_PBSIZE: Buffer size for Console output 3466 3467- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 3468 3469- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 3470 the application (usually a Linux kernel) when it is 3471 booted 3472 3473- CONFIG_SYS_BAUDRATE_TABLE: 3474 List of legal baudrate settings for this board. 3475 3476- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 3477 Begin and End addresses of the area used by the 3478 simple memory test. 3479 3480- CONFIG_SYS_ALT_MEMTEST: 3481 Enable an alternate, more extensive memory test. 3482 3483- CONFIG_SYS_MEMTEST_SCRATCH: 3484 Scratch address used by the alternate memory test 3485 You only need to set this if address zero isn't writeable 3486 3487- CONFIG_SYS_MEM_RESERVE_SECURE 3488 Only implemented for ARMv8 for now. 3489 If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory 3490 is substracted from total RAM and won't be reported to OS. 3491 This memory can be used as secure memory. A variable 3492 gd->arch.secure_ram is used to track the location. In systems 3493 the RAM base is not zero, or RAM is divided into banks, 3494 this variable needs to be recalcuated to get the address. 3495 3496- CONFIG_SYS_MEM_TOP_HIDE: 3497 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 3498 this specified memory area will get subtracted from the top 3499 (end) of RAM and won't get "touched" at all by U-Boot. By 3500 fixing up gd->ram_size the Linux kernel should gets passed 3501 the now "corrected" memory size and won't touch it either. 3502 This should work for arch/ppc and arch/powerpc. Only Linux 3503 board ports in arch/powerpc with bootwrapper support that 3504 recalculate the memory size from the SDRAM controller setup 3505 will have to get fixed in Linux additionally. 3506 3507 This option can be used as a workaround for the 440EPx/GRx 3508 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 3509 be touched. 3510 3511 WARNING: Please make sure that this value is a multiple of 3512 the Linux page size (normally 4k). If this is not the case, 3513 then the end address of the Linux memory will be located at a 3514 non page size aligned address and this could cause major 3515 problems. 3516 3517- CONFIG_SYS_LOADS_BAUD_CHANGE: 3518 Enable temporary baudrate change while serial download 3519 3520- CONFIG_SYS_SDRAM_BASE: 3521 Physical start address of SDRAM. _Must_ be 0 here. 3522 3523- CONFIG_SYS_FLASH_BASE: 3524 Physical start address of Flash memory. 3525 3526- CONFIG_SYS_MONITOR_BASE: 3527 Physical start address of boot monitor code (set by 3528 make config files to be same as the text base address 3529 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 3530 CONFIG_SYS_FLASH_BASE when booting from flash. 3531 3532- CONFIG_SYS_MONITOR_LEN: 3533 Size of memory reserved for monitor code, used to 3534 determine _at_compile_time_ (!) if the environment is 3535 embedded within the U-Boot image, or in a separate 3536 flash sector. 3537 3538- CONFIG_SYS_MALLOC_LEN: 3539 Size of DRAM reserved for malloc() use. 3540 3541- CONFIG_SYS_MALLOC_F_LEN 3542 Size of the malloc() pool for use before relocation. If 3543 this is defined, then a very simple malloc() implementation 3544 will become available before relocation. The address is just 3545 below the global data, and the stack is moved down to make 3546 space. 3547 3548 This feature allocates regions with increasing addresses 3549 within the region. calloc() is supported, but realloc() 3550 is not available. free() is supported but does nothing. 3551 The memory will be freed (or in fact just forgotten) when 3552 U-Boot relocates itself. 3553 3554- CONFIG_SYS_MALLOC_SIMPLE 3555 Provides a simple and small malloc() and calloc() for those 3556 boards which do not use the full malloc in SPL (which is 3557 enabled with CONFIG_SYS_SPL_MALLOC_START). 3558 3559- CONFIG_SYS_NONCACHED_MEMORY: 3560 Size of non-cached memory area. This area of memory will be 3561 typically located right below the malloc() area and mapped 3562 uncached in the MMU. This is useful for drivers that would 3563 otherwise require a lot of explicit cache maintenance. For 3564 some drivers it's also impossible to properly maintain the 3565 cache. For example if the regions that need to be flushed 3566 are not a multiple of the cache-line size, *and* padding 3567 cannot be allocated between the regions to align them (i.e. 3568 if the HW requires a contiguous array of regions, and the 3569 size of each region is not cache-aligned), then a flush of 3570 one region may result in overwriting data that hardware has 3571 written to another region in the same cache-line. This can 3572 happen for example in network drivers where descriptors for 3573 buffers are typically smaller than the CPU cache-line (e.g. 3574 16 bytes vs. 32 or 64 bytes). 3575 3576 Non-cached memory is only supported on 32-bit ARM at present. 3577 3578- CONFIG_SYS_BOOTM_LEN: 3579 Normally compressed uImages are limited to an 3580 uncompressed size of 8 MBytes. If this is not enough, 3581 you can define CONFIG_SYS_BOOTM_LEN in your board config file 3582 to adjust this setting to your needs. 3583 3584- CONFIG_SYS_BOOTMAPSZ: 3585 Maximum size of memory mapped by the startup code of 3586 the Linux kernel; all data that must be processed by 3587 the Linux kernel (bd_info, boot arguments, FDT blob if 3588 used) must be put below this limit, unless "bootm_low" 3589 environment variable is defined and non-zero. In such case 3590 all data for the Linux kernel must be between "bootm_low" 3591 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 3592 variable "bootm_mapsize" will override the value of 3593 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 3594 then the value in "bootm_size" will be used instead. 3595 3596- CONFIG_SYS_BOOT_RAMDISK_HIGH: 3597 Enable initrd_high functionality. If defined then the 3598 initrd_high feature is enabled and the bootm ramdisk subcommand 3599 is enabled. 3600 3601- CONFIG_SYS_BOOT_GET_CMDLINE: 3602 Enables allocating and saving kernel cmdline in space between 3603 "bootm_low" and "bootm_low" + BOOTMAPSZ. 3604 3605- CONFIG_SYS_BOOT_GET_KBD: 3606 Enables allocating and saving a kernel copy of the bd_info in 3607 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 3608 3609- CONFIG_SYS_MAX_FLASH_BANKS: 3610 Max number of Flash memory banks 3611 3612- CONFIG_SYS_MAX_FLASH_SECT: 3613 Max number of sectors on a Flash chip 3614 3615- CONFIG_SYS_FLASH_ERASE_TOUT: 3616 Timeout for Flash erase operations (in ms) 3617 3618- CONFIG_SYS_FLASH_WRITE_TOUT: 3619 Timeout for Flash write operations (in ms) 3620 3621- CONFIG_SYS_FLASH_LOCK_TOUT 3622 Timeout for Flash set sector lock bit operation (in ms) 3623 3624- CONFIG_SYS_FLASH_UNLOCK_TOUT 3625 Timeout for Flash clear lock bits operation (in ms) 3626 3627- CONFIG_SYS_FLASH_PROTECTION 3628 If defined, hardware flash sectors protection is used 3629 instead of U-Boot software protection. 3630 3631- CONFIG_SYS_DIRECT_FLASH_TFTP: 3632 3633 Enable TFTP transfers directly to flash memory; 3634 without this option such a download has to be 3635 performed in two steps: (1) download to RAM, and (2) 3636 copy from RAM to flash. 3637 3638 The two-step approach is usually more reliable, since 3639 you can check if the download worked before you erase 3640 the flash, but in some situations (when system RAM is 3641 too limited to allow for a temporary copy of the 3642 downloaded image) this option may be very useful. 3643 3644- CONFIG_SYS_FLASH_CFI: 3645 Define if the flash driver uses extra elements in the 3646 common flash structure for storing flash geometry. 3647 3648- CONFIG_FLASH_CFI_DRIVER 3649 This option also enables the building of the cfi_flash driver 3650 in the drivers directory 3651 3652- CONFIG_FLASH_CFI_MTD 3653 This option enables the building of the cfi_mtd driver 3654 in the drivers directory. The driver exports CFI flash 3655 to the MTD layer. 3656 3657- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 3658 Use buffered writes to flash. 3659 3660- CONFIG_FLASH_SPANSION_S29WS_N 3661 s29ws-n MirrorBit flash has non-standard addresses for buffered 3662 write commands. 3663 3664- CONFIG_SYS_FLASH_QUIET_TEST 3665 If this option is defined, the common CFI flash doesn't 3666 print it's warning upon not recognized FLASH banks. This 3667 is useful, if some of the configured banks are only 3668 optionally available. 3669 3670- CONFIG_FLASH_SHOW_PROGRESS 3671 If defined (must be an integer), print out countdown 3672 digits and dots. Recommended value: 45 (9..1) for 80 3673 column displays, 15 (3..1) for 40 column displays. 3674 3675- CONFIG_FLASH_VERIFY 3676 If defined, the content of the flash (destination) is compared 3677 against the source after the write operation. An error message 3678 will be printed when the contents are not identical. 3679 Please note that this option is useless in nearly all cases, 3680 since such flash programming errors usually are detected earlier 3681 while unprotecting/erasing/programming. Please only enable 3682 this option if you really know what you are doing. 3683 3684- CONFIG_SYS_RX_ETH_BUFFER: 3685 Defines the number of Ethernet receive buffers. On some 3686 Ethernet controllers it is recommended to set this value 3687 to 8 or even higher (EEPRO100 or 405 EMAC), since all 3688 buffers can be full shortly after enabling the interface 3689 on high Ethernet traffic. 3690 Defaults to 4 if not defined. 3691 3692- CONFIG_ENV_MAX_ENTRIES 3693 3694 Maximum number of entries in the hash table that is used 3695 internally to store the environment settings. The default 3696 setting is supposed to be generous and should work in most 3697 cases. This setting can be used to tune behaviour; see 3698 lib/hashtable.c for details. 3699 3700- CONFIG_ENV_FLAGS_LIST_DEFAULT 3701- CONFIG_ENV_FLAGS_LIST_STATIC 3702 Enable validation of the values given to environment variables when 3703 calling env set. Variables can be restricted to only decimal, 3704 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined, 3705 the variables can also be restricted to IP address or MAC address. 3706 3707 The format of the list is: 3708 type_attribute = [s|d|x|b|i|m] 3709 access_attribute = [a|r|o|c] 3710 attributes = type_attribute[access_attribute] 3711 entry = variable_name[:attributes] 3712 list = entry[,list] 3713 3714 The type attributes are: 3715 s - String (default) 3716 d - Decimal 3717 x - Hexadecimal 3718 b - Boolean ([1yYtT|0nNfF]) 3719 i - IP address 3720 m - MAC address 3721 3722 The access attributes are: 3723 a - Any (default) 3724 r - Read-only 3725 o - Write-once 3726 c - Change-default 3727 3728 - CONFIG_ENV_FLAGS_LIST_DEFAULT 3729 Define this to a list (string) to define the ".flags" 3730 environment variable in the default or embedded environment. 3731 3732 - CONFIG_ENV_FLAGS_LIST_STATIC 3733 Define this to a list (string) to define validation that 3734 should be done if an entry is not found in the ".flags" 3735 environment variable. To override a setting in the static 3736 list, simply add an entry for the same variable name to the 3737 ".flags" variable. 3738 3739 If CONFIG_REGEX is defined, the variable_name above is evaluated as a 3740 regular expression. This allows multiple variables to define the same 3741 flags without explicitly listing them for each variable. 3742 3743- CONFIG_ENV_ACCESS_IGNORE_FORCE 3744 If defined, don't allow the -f switch to env set override variable 3745 access flags. 3746 3747- CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only) 3748 This is set by OMAP boards for the max time that reset should 3749 be asserted. See doc/README.omap-reset-time for details on how 3750 the value can be calculated on a given board. 3751 3752- CONFIG_USE_STDINT 3753 If stdint.h is available with your toolchain you can define this 3754 option to enable it. You can provide option 'USE_STDINT=1' when 3755 building U-Boot to enable this. 3756 3757The following definitions that deal with the placement and management 3758of environment data (variable area); in general, we support the 3759following configurations: 3760 3761- CONFIG_BUILD_ENVCRC: 3762 3763 Builds up envcrc with the target environment so that external utils 3764 may easily extract it and embed it in final U-Boot images. 3765 3766- CONFIG_ENV_IS_IN_FLASH: 3767 3768 Define this if the environment is in flash memory. 3769 3770 a) The environment occupies one whole flash sector, which is 3771 "embedded" in the text segment with the U-Boot code. This 3772 happens usually with "bottom boot sector" or "top boot 3773 sector" type flash chips, which have several smaller 3774 sectors at the start or the end. For instance, such a 3775 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 3776 such a case you would place the environment in one of the 3777 4 kB sectors - with U-Boot code before and after it. With 3778 "top boot sector" type flash chips, you would put the 3779 environment in one of the last sectors, leaving a gap 3780 between U-Boot and the environment. 3781 3782 - CONFIG_ENV_OFFSET: 3783 3784 Offset of environment data (variable area) to the 3785 beginning of flash memory; for instance, with bottom boot 3786 type flash chips the second sector can be used: the offset 3787 for this sector is given here. 3788 3789 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 3790 3791 - CONFIG_ENV_ADDR: 3792 3793 This is just another way to specify the start address of 3794 the flash sector containing the environment (instead of 3795 CONFIG_ENV_OFFSET). 3796 3797 - CONFIG_ENV_SECT_SIZE: 3798 3799 Size of the sector containing the environment. 3800 3801 3802 b) Sometimes flash chips have few, equal sized, BIG sectors. 3803 In such a case you don't want to spend a whole sector for 3804 the environment. 3805 3806 - CONFIG_ENV_SIZE: 3807 3808 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 3809 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 3810 of this flash sector for the environment. This saves 3811 memory for the RAM copy of the environment. 3812 3813 It may also save flash memory if you decide to use this 3814 when your environment is "embedded" within U-Boot code, 3815 since then the remainder of the flash sector could be used 3816 for U-Boot code. It should be pointed out that this is 3817 STRONGLY DISCOURAGED from a robustness point of view: 3818 updating the environment in flash makes it always 3819 necessary to erase the WHOLE sector. If something goes 3820 wrong before the contents has been restored from a copy in 3821 RAM, your target system will be dead. 3822 3823 - CONFIG_ENV_ADDR_REDUND 3824 CONFIG_ENV_SIZE_REDUND 3825 3826 These settings describe a second storage area used to hold 3827 a redundant copy of the environment data, so that there is 3828 a valid backup copy in case there is a power failure during 3829 a "saveenv" operation. 3830 3831BE CAREFUL! Any changes to the flash layout, and some changes to the 3832source code will make it necessary to adapt <board>/u-boot.lds* 3833accordingly! 3834 3835 3836- CONFIG_ENV_IS_IN_NVRAM: 3837 3838 Define this if you have some non-volatile memory device 3839 (NVRAM, battery buffered SRAM) which you want to use for the 3840 environment. 3841 3842 - CONFIG_ENV_ADDR: 3843 - CONFIG_ENV_SIZE: 3844 3845 These two #defines are used to determine the memory area you 3846 want to use for environment. It is assumed that this memory 3847 can just be read and written to, without any special 3848 provision. 3849 3850BE CAREFUL! The first access to the environment happens quite early 3851in U-Boot initialization (when we try to get the setting of for the 3852console baudrate). You *MUST* have mapped your NVRAM area then, or 3853U-Boot will hang. 3854 3855Please note that even with NVRAM we still use a copy of the 3856environment in RAM: we could work on NVRAM directly, but we want to 3857keep settings there always unmodified except somebody uses "saveenv" 3858to save the current settings. 3859 3860 3861- CONFIG_ENV_IS_IN_EEPROM: 3862 3863 Use this if you have an EEPROM or similar serial access 3864 device and a driver for it. 3865 3866 - CONFIG_ENV_OFFSET: 3867 - CONFIG_ENV_SIZE: 3868 3869 These two #defines specify the offset and size of the 3870 environment area within the total memory of your EEPROM. 3871 3872 - CONFIG_SYS_I2C_EEPROM_ADDR: 3873 If defined, specified the chip address of the EEPROM device. 3874 The default address is zero. 3875 3876 - CONFIG_SYS_I2C_EEPROM_BUS: 3877 If defined, specified the i2c bus of the EEPROM device. 3878 3879 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 3880 If defined, the number of bits used to address bytes in a 3881 single page in the EEPROM device. A 64 byte page, for example 3882 would require six bits. 3883 3884 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 3885 If defined, the number of milliseconds to delay between 3886 page writes. The default is zero milliseconds. 3887 3888 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 3889 The length in bytes of the EEPROM memory array address. Note 3890 that this is NOT the chip address length! 3891 3892 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 3893 EEPROM chips that implement "address overflow" are ones 3894 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 3895 address and the extra bits end up in the "chip address" bit 3896 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 3897 byte chips. 3898 3899 Note that we consider the length of the address field to 3900 still be one byte because the extra address bits are hidden 3901 in the chip address. 3902 3903 - CONFIG_SYS_EEPROM_SIZE: 3904 The size in bytes of the EEPROM device. 3905 3906 - CONFIG_ENV_EEPROM_IS_ON_I2C 3907 define this, if you have I2C and SPI activated, and your 3908 EEPROM, which holds the environment, is on the I2C bus. 3909 3910 - CONFIG_I2C_ENV_EEPROM_BUS 3911 if you have an Environment on an EEPROM reached over 3912 I2C muxes, you can define here, how to reach this 3913 EEPROM. For example: 3914 3915 #define CONFIG_I2C_ENV_EEPROM_BUS 1 3916 3917 EEPROM which holds the environment, is reached over 3918 a pca9547 i2c mux with address 0x70, channel 3. 3919 3920- CONFIG_ENV_IS_IN_DATAFLASH: 3921 3922 Define this if you have a DataFlash memory device which you 3923 want to use for the environment. 3924 3925 - CONFIG_ENV_OFFSET: 3926 - CONFIG_ENV_ADDR: 3927 - CONFIG_ENV_SIZE: 3928 3929 These three #defines specify the offset and size of the 3930 environment area within the total memory of your DataFlash placed 3931 at the specified address. 3932 3933- CONFIG_ENV_IS_IN_SPI_FLASH: 3934 3935 Define this if you have a SPI Flash memory device which you 3936 want to use for the environment. 3937 3938 - CONFIG_ENV_OFFSET: 3939 - CONFIG_ENV_SIZE: 3940 3941 These two #defines specify the offset and size of the 3942 environment area within the SPI Flash. CONFIG_ENV_OFFSET must be 3943 aligned to an erase sector boundary. 3944 3945 - CONFIG_ENV_SECT_SIZE: 3946 3947 Define the SPI flash's sector size. 3948 3949 - CONFIG_ENV_OFFSET_REDUND (optional): 3950 3951 This setting describes a second storage area of CONFIG_ENV_SIZE 3952 size used to hold a redundant copy of the environment data, so 3953 that there is a valid backup copy in case there is a power failure 3954 during a "saveenv" operation. CONFIG_ENV_OFFSET_REDUND must be 3955 aligned to an erase sector boundary. 3956 3957 - CONFIG_ENV_SPI_BUS (optional): 3958 - CONFIG_ENV_SPI_CS (optional): 3959 3960 Define the SPI bus and chip select. If not defined they will be 0. 3961 3962 - CONFIG_ENV_SPI_MAX_HZ (optional): 3963 3964 Define the SPI max work clock. If not defined then use 1MHz. 3965 3966 - CONFIG_ENV_SPI_MODE (optional): 3967 3968 Define the SPI work mode. If not defined then use SPI_MODE_3. 3969 3970- CONFIG_ENV_IS_IN_REMOTE: 3971 3972 Define this if you have a remote memory space which you 3973 want to use for the local device's environment. 3974 3975 - CONFIG_ENV_ADDR: 3976 - CONFIG_ENV_SIZE: 3977 3978 These two #defines specify the address and size of the 3979 environment area within the remote memory space. The 3980 local device can get the environment from remote memory 3981 space by SRIO or PCIE links. 3982 3983BE CAREFUL! For some special cases, the local device can not use 3984"saveenv" command. For example, the local device will get the 3985environment stored in a remote NOR flash by SRIO or PCIE link, 3986but it can not erase, write this NOR flash by SRIO or PCIE interface. 3987 3988- CONFIG_ENV_IS_IN_NAND: 3989 3990 Define this if you have a NAND device which you want to use 3991 for the environment. 3992 3993 - CONFIG_ENV_OFFSET: 3994 - CONFIG_ENV_SIZE: 3995 3996 These two #defines specify the offset and size of the environment 3997 area within the first NAND device. CONFIG_ENV_OFFSET must be 3998 aligned to an erase block boundary. 3999 4000 - CONFIG_ENV_OFFSET_REDUND (optional): 4001 4002 This setting describes a second storage area of CONFIG_ENV_SIZE 4003 size used to hold a redundant copy of the environment data, so 4004 that there is a valid backup copy in case there is a power failure 4005 during a "saveenv" operation. CONFIG_ENV_OFFSET_REDUND must be 4006 aligned to an erase block boundary. 4007 4008 - CONFIG_ENV_RANGE (optional): 4009 4010 Specifies the length of the region in which the environment 4011 can be written. This should be a multiple of the NAND device's 4012 block size. Specifying a range with more erase blocks than 4013 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 4014 the range to be avoided. 4015 4016 - CONFIG_ENV_OFFSET_OOB (optional): 4017 4018 Enables support for dynamically retrieving the offset of the 4019 environment from block zero's out-of-band data. The 4020 "nand env.oob" command can be used to record this offset. 4021 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 4022 using CONFIG_ENV_OFFSET_OOB. 4023 4024- CONFIG_NAND_ENV_DST 4025 4026 Defines address in RAM to which the nand_spl code should copy the 4027 environment. If redundant environment is used, it will be copied to 4028 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 4029 4030- CONFIG_ENV_IS_IN_UBI: 4031 4032 Define this if you have an UBI volume that you want to use for the 4033 environment. This has the benefit of wear-leveling the environment 4034 accesses, which is important on NAND. 4035 4036 - CONFIG_ENV_UBI_PART: 4037 4038 Define this to a string that is the mtd partition containing the UBI. 4039 4040 - CONFIG_ENV_UBI_VOLUME: 4041 4042 Define this to the name of the volume that you want to store the 4043 environment in. 4044 4045 - CONFIG_ENV_UBI_VOLUME_REDUND: 4046 4047 Define this to the name of another volume to store a second copy of 4048 the environment in. This will enable redundant environments in UBI. 4049 It is assumed that both volumes are in the same MTD partition. 4050 4051 - CONFIG_UBI_SILENCE_MSG 4052 - CONFIG_UBIFS_SILENCE_MSG 4053 4054 You will probably want to define these to avoid a really noisy system 4055 when storing the env in UBI. 4056 4057- CONFIG_ENV_IS_IN_FAT: 4058 Define this if you want to use the FAT file system for the environment. 4059 4060 - FAT_ENV_INTERFACE: 4061 4062 Define this to a string that is the name of the block device. 4063 4064 - FAT_ENV_DEVICE_AND_PART: 4065 4066 Define this to a string to specify the partition of the device. It can 4067 be as following: 4068 4069 "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1) 4070 - "D:P": device D partition P. Error occurs if device D has no 4071 partition table. 4072 - "D:0": device D. 4073 - "D" or "D:": device D partition 1 if device D has partition 4074 table, or the whole device D if has no partition 4075 table. 4076 - "D:auto": first partition in device D with bootable flag set. 4077 If none, first valid partition in device D. If no 4078 partition table then means device D. 4079 4080 - FAT_ENV_FILE: 4081 4082 It's a string of the FAT file name. This file use to store the 4083 environment. 4084 4085 - CONFIG_FAT_WRITE: 4086 This should be defined. Otherwise it cannot save the environment file. 4087 4088- CONFIG_ENV_IS_IN_MMC: 4089 4090 Define this if you have an MMC device which you want to use for the 4091 environment. 4092 4093 - CONFIG_SYS_MMC_ENV_DEV: 4094 4095 Specifies which MMC device the environment is stored in. 4096 4097 - CONFIG_SYS_MMC_ENV_PART (optional): 4098 4099 Specifies which MMC partition the environment is stored in. If not 4100 set, defaults to partition 0, the user area. Common values might be 4101 1 (first MMC boot partition), 2 (second MMC boot partition). 4102 4103 - CONFIG_ENV_OFFSET: 4104 - CONFIG_ENV_SIZE: 4105 4106 These two #defines specify the offset and size of the environment 4107 area within the specified MMC device. 4108 4109 If offset is positive (the usual case), it is treated as relative to 4110 the start of the MMC partition. If offset is negative, it is treated 4111 as relative to the end of the MMC partition. This can be useful if 4112 your board may be fitted with different MMC devices, which have 4113 different sizes for the MMC partitions, and you always want the 4114 environment placed at the very end of the partition, to leave the 4115 maximum possible space before it, to store other data. 4116 4117 These two values are in units of bytes, but must be aligned to an 4118 MMC sector boundary. 4119 4120 - CONFIG_ENV_OFFSET_REDUND (optional): 4121 4122 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to 4123 hold a redundant copy of the environment data. This provides a 4124 valid backup copy in case the other copy is corrupted, e.g. due 4125 to a power failure during a "saveenv" operation. 4126 4127 This value may also be positive or negative; this is handled in the 4128 same way as CONFIG_ENV_OFFSET. 4129 4130 This value is also in units of bytes, but must also be aligned to 4131 an MMC sector boundary. 4132 4133 - CONFIG_ENV_SIZE_REDUND (optional): 4134 4135 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is 4136 set. If this value is set, it must be set to the same value as 4137 CONFIG_ENV_SIZE. 4138 4139- CONFIG_SYS_SPI_INIT_OFFSET 4140 4141 Defines offset to the initial SPI buffer area in DPRAM. The 4142 area is used at an early stage (ROM part) if the environment 4143 is configured to reside in the SPI EEPROM: We need a 520 byte 4144 scratch DPRAM area. It is used between the two initialization 4145 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 4146 to be a good choice since it makes it far enough from the 4147 start of the data area as well as from the stack pointer. 4148 4149Please note that the environment is read-only until the monitor 4150has been relocated to RAM and a RAM copy of the environment has been 4151created; also, when using EEPROM you will have to use getenv_f() 4152until then to read environment variables. 4153 4154The environment is protected by a CRC32 checksum. Before the monitor 4155is relocated into RAM, as a result of a bad CRC you will be working 4156with the compiled-in default environment - *silently*!!! [This is 4157necessary, because the first environment variable we need is the 4158"baudrate" setting for the console - if we have a bad CRC, we don't 4159have any device yet where we could complain.] 4160 4161Note: once the monitor has been relocated, then it will complain if 4162the default environment is used; a new CRC is computed as soon as you 4163use the "saveenv" command to store a valid environment. 4164 4165- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 4166 Echo the inverted Ethernet link state to the fault LED. 4167 4168 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 4169 also needs to be defined. 4170 4171- CONFIG_SYS_FAULT_MII_ADDR: 4172 MII address of the PHY to check for the Ethernet link state. 4173 4174- CONFIG_NS16550_MIN_FUNCTIONS: 4175 Define this if you desire to only have use of the NS16550_init 4176 and NS16550_putc functions for the serial driver located at 4177 drivers/serial/ns16550.c. This option is useful for saving 4178 space for already greatly restricted images, including but not 4179 limited to NAND_SPL configurations. 4180 4181- CONFIG_DISPLAY_BOARDINFO 4182 Display information about the board that U-Boot is running on 4183 when U-Boot starts up. The board function checkboard() is called 4184 to do this. 4185 4186- CONFIG_DISPLAY_BOARDINFO_LATE 4187 Similar to the previous option, but display this information 4188 later, once stdio is running and output goes to the LCD, if 4189 present. 4190 4191- CONFIG_BOARD_SIZE_LIMIT: 4192 Maximum size of the U-Boot image. When defined, the 4193 build system checks that the actual size does not 4194 exceed it. 4195 4196Low Level (hardware related) configuration options: 4197--------------------------------------------------- 4198 4199- CONFIG_SYS_CACHELINE_SIZE: 4200 Cache Line Size of the CPU. 4201 4202- CONFIG_SYS_DEFAULT_IMMR: 4203 Default address of the IMMR after system reset. 4204 4205 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 4206 and RPXsuper) to be able to adjust the position of 4207 the IMMR register after a reset. 4208 4209- CONFIG_SYS_CCSRBAR_DEFAULT: 4210 Default (power-on reset) physical address of CCSR on Freescale 4211 PowerPC SOCs. 4212 4213- CONFIG_SYS_CCSRBAR: 4214 Virtual address of CCSR. On a 32-bit build, this is typically 4215 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 4216 4217 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 4218 for cross-platform code that uses that macro instead. 4219 4220- CONFIG_SYS_CCSRBAR_PHYS: 4221 Physical address of CCSR. CCSR can be relocated to a new 4222 physical address, if desired. In this case, this macro should 4223 be set to that address. Otherwise, it should be set to the 4224 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 4225 is typically relocated on 36-bit builds. It is recommended 4226 that this macro be defined via the _HIGH and _LOW macros: 4227 4228 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 4229 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 4230 4231- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 4232 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 4233 either 0 (32-bit build) or 0xF (36-bit build). This macro is 4234 used in assembly code, so it must not contain typecasts or 4235 integer size suffixes (e.g. "ULL"). 4236 4237- CONFIG_SYS_CCSRBAR_PHYS_LOW: 4238 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 4239 used in assembly code, so it must not contain typecasts or 4240 integer size suffixes (e.g. "ULL"). 4241 4242- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 4243 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 4244 forced to a value that ensures that CCSR is not relocated. 4245 4246- Floppy Disk Support: 4247 CONFIG_SYS_FDC_DRIVE_NUMBER 4248 4249 the default drive number (default value 0) 4250 4251 CONFIG_SYS_ISA_IO_STRIDE 4252 4253 defines the spacing between FDC chipset registers 4254 (default value 1) 4255 4256 CONFIG_SYS_ISA_IO_OFFSET 4257 4258 defines the offset of register from address. It 4259 depends on which part of the data bus is connected to 4260 the FDC chipset. (default value 0) 4261 4262 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 4263 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 4264 default value. 4265 4266 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 4267 fdc_hw_init() is called at the beginning of the FDC 4268 setup. fdc_hw_init() must be provided by the board 4269 source code. It is used to make hardware-dependent 4270 initializations. 4271 4272- CONFIG_IDE_AHB: 4273 Most IDE controllers were designed to be connected with PCI 4274 interface. Only few of them were designed for AHB interface. 4275 When software is doing ATA command and data transfer to 4276 IDE devices through IDE-AHB controller, some additional 4277 registers accessing to these kind of IDE-AHB controller 4278 is required. 4279 4280- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 4281 DO NOT CHANGE unless you know exactly what you're 4282 doing! (11-4) [MPC8xx/82xx systems only] 4283 4284- CONFIG_SYS_INIT_RAM_ADDR: 4285 4286 Start address of memory area that can be used for 4287 initial data and stack; please note that this must be 4288 writable memory that is working WITHOUT special 4289 initialization, i. e. you CANNOT use normal RAM which 4290 will become available only after programming the 4291 memory controller and running certain initialization 4292 sequences. 4293 4294 U-Boot uses the following memory types: 4295 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 4296 - MPC824X: data cache 4297 - PPC4xx: data cache 4298 4299- CONFIG_SYS_GBL_DATA_OFFSET: 4300 4301 Offset of the initial data structure in the memory 4302 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 4303 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 4304 data is located at the end of the available space 4305 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 4306 GENERATED_GBL_DATA_SIZE), and the initial stack is just 4307 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 4308 CONFIG_SYS_GBL_DATA_OFFSET) downward. 4309 4310 Note: 4311 On the MPC824X (or other systems that use the data 4312 cache for initial memory) the address chosen for 4313 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 4314 point to an otherwise UNUSED address space between 4315 the top of RAM and the start of the PCI space. 4316 4317- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 4318 4319- CONFIG_SYS_SYPCR: System Protection Control (11-9) 4320 4321- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 4322 4323- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 4324 4325- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 4326 4327- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 4328 4329- CONFIG_SYS_OR_TIMING_SDRAM: 4330 SDRAM timing 4331 4332- CONFIG_SYS_MAMR_PTA: 4333 periodic timer for refresh 4334 4335- CONFIG_SYS_DER: Debug Event Register (37-47) 4336 4337- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 4338 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 4339 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 4340 CONFIG_SYS_BR1_PRELIM: 4341 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 4342 4343- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 4344 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 4345 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 4346 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 4347 4348- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 4349 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 4350 Machine Mode Register and Memory Periodic Timer 4351 Prescaler definitions (SDRAM timing) 4352 4353- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 4354 enable I2C microcode relocation patch (MPC8xx); 4355 define relocation offset in DPRAM [DSP2] 4356 4357- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 4358 enable SMC microcode relocation patch (MPC8xx); 4359 define relocation offset in DPRAM [SMC1] 4360 4361- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 4362 enable SPI microcode relocation patch (MPC8xx); 4363 define relocation offset in DPRAM [SCC4] 4364 4365- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 4366 Offset of the bootmode word in DPRAM used by post 4367 (Power On Self Tests). This definition overrides 4368 #define'd default value in commproc.h resp. 4369 cpm_8260.h. 4370 4371- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 4372 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 4373 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 4374 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 4375 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 4376 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 4377 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 4378 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 4379 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 4380 4381- CONFIG_PCI_DISABLE_PCIE: 4382 Disable PCI-Express on systems where it is supported but not 4383 required. 4384 4385- CONFIG_PCI_ENUM_ONLY 4386 Only scan through and get the devices on the buses. 4387 Don't do any setup work, presumably because someone or 4388 something has already done it, and we don't need to do it 4389 a second time. Useful for platforms that are pre-booted 4390 by coreboot or similar. 4391 4392- CONFIG_PCI_INDIRECT_BRIDGE: 4393 Enable support for indirect PCI bridges. 4394 4395- CONFIG_SYS_SRIO: 4396 Chip has SRIO or not 4397 4398- CONFIG_SRIO1: 4399 Board has SRIO 1 port available 4400 4401- CONFIG_SRIO2: 4402 Board has SRIO 2 port available 4403 4404- CONFIG_SRIO_PCIE_BOOT_MASTER 4405 Board can support master function for Boot from SRIO and PCIE 4406 4407- CONFIG_SYS_SRIOn_MEM_VIRT: 4408 Virtual Address of SRIO port 'n' memory region 4409 4410- CONFIG_SYS_SRIOn_MEM_PHYS: 4411 Physical Address of SRIO port 'n' memory region 4412 4413- CONFIG_SYS_SRIOn_MEM_SIZE: 4414 Size of SRIO port 'n' memory region 4415 4416- CONFIG_SYS_NAND_BUSWIDTH_16BIT 4417 Defined to tell the NAND controller that the NAND chip is using 4418 a 16 bit bus. 4419 Not all NAND drivers use this symbol. 4420 Example of drivers that use it: 4421 - drivers/mtd/nand/ndfc.c 4422 - drivers/mtd/nand/mxc_nand.c 4423 4424- CONFIG_SYS_NDFC_EBC0_CFG 4425 Sets the EBC0_CFG register for the NDFC. If not defined 4426 a default value will be used. 4427 4428- CONFIG_SPD_EEPROM 4429 Get DDR timing information from an I2C EEPROM. Common 4430 with pluggable memory modules such as SODIMMs 4431 4432 SPD_EEPROM_ADDRESS 4433 I2C address of the SPD EEPROM 4434 4435- CONFIG_SYS_SPD_BUS_NUM 4436 If SPD EEPROM is on an I2C bus other than the first 4437 one, specify here. Note that the value must resolve 4438 to something your driver can deal with. 4439 4440- CONFIG_SYS_DDR_RAW_TIMING 4441 Get DDR timing information from other than SPD. Common with 4442 soldered DDR chips onboard without SPD. DDR raw timing 4443 parameters are extracted from datasheet and hard-coded into 4444 header files or board specific files. 4445 4446- CONFIG_FSL_DDR_INTERACTIVE 4447 Enable interactive DDR debugging. See doc/README.fsl-ddr. 4448 4449- CONFIG_FSL_DDR_SYNC_REFRESH 4450 Enable sync of refresh for multiple controllers. 4451 4452- CONFIG_FSL_DDR_BIST 4453 Enable built-in memory test for Freescale DDR controllers. 4454 4455- CONFIG_SYS_83XX_DDR_USES_CS0 4456 Only for 83xx systems. If specified, then DDR should 4457 be configured using CS0 and CS1 instead of CS2 and CS3. 4458 4459- CONFIG_ETHER_ON_FEC[12] 4460 Define to enable FEC[12] on a 8xx series processor. 4461 4462- CONFIG_FEC[12]_PHY 4463 Define to the hardcoded PHY address which corresponds 4464 to the given FEC; i. e. 4465 #define CONFIG_FEC1_PHY 4 4466 means that the PHY with address 4 is connected to FEC1 4467 4468 When set to -1, means to probe for first available. 4469 4470- CONFIG_FEC[12]_PHY_NORXERR 4471 The PHY does not have a RXERR line (RMII only). 4472 (so program the FEC to ignore it). 4473 4474- CONFIG_RMII 4475 Enable RMII mode for all FECs. 4476 Note that this is a global option, we can't 4477 have one FEC in standard MII mode and another in RMII mode. 4478 4479- CONFIG_CRC32_VERIFY 4480 Add a verify option to the crc32 command. 4481 The syntax is: 4482 4483 => crc32 -v <address> <count> <crc32> 4484 4485 Where address/count indicate a memory area 4486 and crc32 is the correct crc32 which the 4487 area should have. 4488 4489- CONFIG_LOOPW 4490 Add the "loopw" memory command. This only takes effect if 4491 the memory commands are activated globally (CONFIG_CMD_MEM). 4492 4493- CONFIG_MX_CYCLIC 4494 Add the "mdc" and "mwc" memory commands. These are cyclic 4495 "md/mw" commands. 4496 Examples: 4497 4498 => mdc.b 10 4 500 4499 This command will print 4 bytes (10,11,12,13) each 500 ms. 4500 4501 => mwc.l 100 12345678 10 4502 This command will write 12345678 to address 100 all 10 ms. 4503 4504 This only takes effect if the memory commands are activated 4505 globally (CONFIG_CMD_MEM). 4506 4507- CONFIG_SKIP_LOWLEVEL_INIT 4508 [ARM, NDS32, MIPS only] If this variable is defined, then certain 4509 low level initializations (like setting up the memory 4510 controller) are omitted and/or U-Boot does not 4511 relocate itself into RAM. 4512 4513 Normally this variable MUST NOT be defined. The only 4514 exception is when U-Boot is loaded (to RAM) by some 4515 other boot loader or by a debugger which performs 4516 these initializations itself. 4517 4518- CONFIG_SKIP_LOWLEVEL_INIT_ONLY 4519 [ARM926EJ-S only] This allows just the call to lowlevel_init() 4520 to be skipped. The normal CP15 init (such as enabling the 4521 instruction cache) is still performed. 4522 4523- CONFIG_SPL_BUILD 4524 Modifies the behaviour of start.S when compiling a loader 4525 that is executed before the actual U-Boot. E.g. when 4526 compiling a NAND SPL. 4527 4528- CONFIG_TPL_BUILD 4529 Modifies the behaviour of start.S when compiling a loader 4530 that is executed after the SPL and before the actual U-Boot. 4531 It is loaded by the SPL. 4532 4533- CONFIG_SYS_MPC85XX_NO_RESETVEC 4534 Only for 85xx systems. If this variable is specified, the section 4535 .resetvec is not kept and the section .bootpg is placed in the 4536 previous 4k of the .text section. 4537 4538- CONFIG_ARCH_MAP_SYSMEM 4539 Generally U-Boot (and in particular the md command) uses 4540 effective address. It is therefore not necessary to regard 4541 U-Boot address as virtual addresses that need to be translated 4542 to physical addresses. However, sandbox requires this, since 4543 it maintains its own little RAM buffer which contains all 4544 addressable memory. This option causes some memory accesses 4545 to be mapped through map_sysmem() / unmap_sysmem(). 4546 4547- CONFIG_X86_RESET_VECTOR 4548 If defined, the x86 reset vector code is included. This is not 4549 needed when U-Boot is running from Coreboot. 4550 4551- CONFIG_SYS_MPUCLK 4552 Defines the MPU clock speed (in MHz). 4553 4554 NOTE : currently only supported on AM335x platforms. 4555 4556- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC: 4557 Enables the RTC32K OSC on AM33xx based plattforms 4558 4559- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE 4560 Option to disable subpage write in NAND driver 4561 driver that uses this: 4562 drivers/mtd/nand/davinci_nand.c 4563 4564Freescale QE/FMAN Firmware Support: 4565----------------------------------- 4566 4567The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 4568loading of "firmware", which is encoded in the QE firmware binary format. 4569This firmware often needs to be loaded during U-Boot booting, so macros 4570are used to identify the storage device (NOR flash, SPI, etc) and the address 4571within that device. 4572 4573- CONFIG_SYS_FMAN_FW_ADDR 4574 The address in the storage device where the FMAN microcode is located. The 4575 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4576 is also specified. 4577 4578- CONFIG_SYS_QE_FW_ADDR 4579 The address in the storage device where the QE microcode is located. The 4580 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4581 is also specified. 4582 4583- CONFIG_SYS_QE_FMAN_FW_LENGTH 4584 The maximum possible size of the firmware. The firmware binary format 4585 has a field that specifies the actual size of the firmware, but it 4586 might not be possible to read any part of the firmware unless some 4587 local storage is allocated to hold the entire firmware first. 4588 4589- CONFIG_SYS_QE_FMAN_FW_IN_NOR 4590 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 4591 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 4592 virtual address in NOR flash. 4593 4594- CONFIG_SYS_QE_FMAN_FW_IN_NAND 4595 Specifies that QE/FMAN firmware is located in NAND flash. 4596 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 4597 4598- CONFIG_SYS_QE_FMAN_FW_IN_MMC 4599 Specifies that QE/FMAN firmware is located on the primary SD/MMC 4600 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 4601 4602- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE 4603 Specifies that QE/FMAN firmware is located in the remote (master) 4604 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which 4605 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound 4606 window->master inbound window->master LAW->the ucode address in 4607 master's memory space. 4608 4609Freescale Layerscape Management Complex Firmware Support: 4610--------------------------------------------------------- 4611The Freescale Layerscape Management Complex (MC) supports the loading of 4612"firmware". 4613This firmware often needs to be loaded during U-Boot booting, so macros 4614are used to identify the storage device (NOR flash, SPI, etc) and the address 4615within that device. 4616 4617- CONFIG_FSL_MC_ENET 4618 Enable the MC driver for Layerscape SoCs. 4619 4620Freescale Layerscape Debug Server Support: 4621------------------------------------------- 4622The Freescale Layerscape Debug Server Support supports the loading of 4623"Debug Server firmware" and triggering SP boot-rom. 4624This firmware often needs to be loaded during U-Boot booting. 4625 4626- CONFIG_SYS_MC_RSV_MEM_ALIGN 4627 Define alignment of reserved memory MC requires 4628 4629Reproducible builds 4630------------------- 4631 4632In order to achieve reproducible builds, timestamps used in the U-Boot build 4633process have to be set to a fixed value. 4634 4635This is done using the SOURCE_DATE_EPOCH environment variable. 4636SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration 4637option for U-Boot or an environment variable in U-Boot. 4638 4639SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC. 4640 4641Building the Software: 4642====================== 4643 4644Building U-Boot has been tested in several native build environments 4645and in many different cross environments. Of course we cannot support 4646all possibly existing versions of cross development tools in all 4647(potentially obsolete) versions. In case of tool chain problems we 4648recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 4649which is extensively used to build and test U-Boot. 4650 4651If you are not using a native environment, it is assumed that you 4652have GNU cross compiling tools available in your path. In this case, 4653you must set the environment variable CROSS_COMPILE in your shell. 4654Note that no changes to the Makefile or any other source files are 4655necessary. For example using the ELDK on a 4xx CPU, please enter: 4656 4657 $ CROSS_COMPILE=ppc_4xx- 4658 $ export CROSS_COMPILE 4659 4660Note: If you wish to generate Windows versions of the utilities in 4661 the tools directory you can use the MinGW toolchain 4662 (http://www.mingw.org). Set your HOST tools to the MinGW 4663 toolchain and execute 'make tools'. For example: 4664 4665 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 4666 4667 Binaries such as tools/mkimage.exe will be created which can 4668 be executed on computers running Windows. 4669 4670U-Boot is intended to be simple to build. After installing the 4671sources you must configure U-Boot for one specific board type. This 4672is done by typing: 4673 4674 make NAME_defconfig 4675 4676where "NAME_defconfig" is the name of one of the existing configu- 4677rations; see boards.cfg for supported names. 4678 4679Note: for some board special configuration names may exist; check if 4680 additional information is available from the board vendor; for 4681 instance, the TQM823L systems are available without (standard) 4682 or with LCD support. You can select such additional "features" 4683 when choosing the configuration, i. e. 4684 4685 make TQM823L_defconfig 4686 - will configure for a plain TQM823L, i. e. no LCD support 4687 4688 make TQM823L_LCD_defconfig 4689 - will configure for a TQM823L with U-Boot console on LCD 4690 4691 etc. 4692 4693 4694Finally, type "make all", and you should get some working U-Boot 4695images ready for download to / installation on your system: 4696 4697- "u-boot.bin" is a raw binary image 4698- "u-boot" is an image in ELF binary format 4699- "u-boot.srec" is in Motorola S-Record format 4700 4701By default the build is performed locally and the objects are saved 4702in the source directory. One of the two methods can be used to change 4703this behavior and build U-Boot to some external directory: 4704 47051. Add O= to the make command line invocations: 4706 4707 make O=/tmp/build distclean 4708 make O=/tmp/build NAME_defconfig 4709 make O=/tmp/build all 4710 47112. Set environment variable KBUILD_OUTPUT to point to the desired location: 4712 4713 export KBUILD_OUTPUT=/tmp/build 4714 make distclean 4715 make NAME_defconfig 4716 make all 4717 4718Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment 4719variable. 4720 4721 4722Please be aware that the Makefiles assume you are using GNU make, so 4723for instance on NetBSD you might need to use "gmake" instead of 4724native "make". 4725 4726 4727If the system board that you have is not listed, then you will need 4728to port U-Boot to your hardware platform. To do this, follow these 4729steps: 4730 47311. Create a new directory to hold your board specific code. Add any 4732 files you need. In your board directory, you will need at least 4733 the "Makefile" and a "<board>.c". 47342. Create a new configuration file "include/configs/<board>.h" for 4735 your board. 47363. If you're porting U-Boot to a new CPU, then also create a new 4737 directory to hold your CPU specific code. Add any files you need. 47384. Run "make <board>_defconfig" with your new name. 47395. Type "make", and you should get a working "u-boot.srec" file 4740 to be installed on your target system. 47416. Debug and solve any problems that might arise. 4742 [Of course, this last step is much harder than it sounds.] 4743 4744 4745Testing of U-Boot Modifications, Ports to New Hardware, etc.: 4746============================================================== 4747 4748If you have modified U-Boot sources (for instance added a new board 4749or support for new devices, a new CPU, etc.) you are expected to 4750provide feedback to the other developers. The feedback normally takes 4751the form of a "patch", i. e. a context diff against a certain (latest 4752official or latest in the git repository) version of U-Boot sources. 4753 4754But before you submit such a patch, please verify that your modifi- 4755cation did not break existing code. At least make sure that *ALL* of 4756the supported boards compile WITHOUT ANY compiler warnings. To do so, 4757just run the buildman script (tools/buildman/buildman), which will 4758configure and build U-Boot for ALL supported system. Be warned, this 4759will take a while. Please see the buildman README, or run 'buildman -H' 4760for documentation. 4761 4762 4763See also "U-Boot Porting Guide" below. 4764 4765 4766Monitor Commands - Overview: 4767============================ 4768 4769go - start application at address 'addr' 4770run - run commands in an environment variable 4771bootm - boot application image from memory 4772bootp - boot image via network using BootP/TFTP protocol 4773bootz - boot zImage from memory 4774tftpboot- boot image via network using TFTP protocol 4775 and env variables "ipaddr" and "serverip" 4776 (and eventually "gatewayip") 4777tftpput - upload a file via network using TFTP protocol 4778rarpboot- boot image via network using RARP/TFTP protocol 4779diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 4780loads - load S-Record file over serial line 4781loadb - load binary file over serial line (kermit mode) 4782md - memory display 4783mm - memory modify (auto-incrementing) 4784nm - memory modify (constant address) 4785mw - memory write (fill) 4786cp - memory copy 4787cmp - memory compare 4788crc32 - checksum calculation 4789i2c - I2C sub-system 4790sspi - SPI utility commands 4791base - print or set address offset 4792printenv- print environment variables 4793setenv - set environment variables 4794saveenv - save environment variables to persistent storage 4795protect - enable or disable FLASH write protection 4796erase - erase FLASH memory 4797flinfo - print FLASH memory information 4798nand - NAND memory operations (see doc/README.nand) 4799bdinfo - print Board Info structure 4800iminfo - print header information for application image 4801coninfo - print console devices and informations 4802ide - IDE sub-system 4803loop - infinite loop on address range 4804loopw - infinite write loop on address range 4805mtest - simple RAM test 4806icache - enable or disable instruction cache 4807dcache - enable or disable data cache 4808reset - Perform RESET of the CPU 4809echo - echo args to console 4810version - print monitor version 4811help - print online help 4812? - alias for 'help' 4813 4814 4815Monitor Commands - Detailed Description: 4816======================================== 4817 4818TODO. 4819 4820For now: just type "help <command>". 4821 4822 4823Environment Variables: 4824====================== 4825 4826U-Boot supports user configuration using Environment Variables which 4827can be made persistent by saving to Flash memory. 4828 4829Environment Variables are set using "setenv", printed using 4830"printenv", and saved to Flash using "saveenv". Using "setenv" 4831without a value can be used to delete a variable from the 4832environment. As long as you don't save the environment you are 4833working with an in-memory copy. In case the Flash area containing the 4834environment is erased by accident, a default environment is provided. 4835 4836Some configuration options can be set using Environment Variables. 4837 4838List of environment variables (most likely not complete): 4839 4840 baudrate - see CONFIG_BAUDRATE 4841 4842 bootdelay - see CONFIG_BOOTDELAY 4843 4844 bootcmd - see CONFIG_BOOTCOMMAND 4845 4846 bootargs - Boot arguments when booting an RTOS image 4847 4848 bootfile - Name of the image to load with TFTP 4849 4850 bootm_low - Memory range available for image processing in the bootm 4851 command can be restricted. This variable is given as 4852 a hexadecimal number and defines lowest address allowed 4853 for use by the bootm command. See also "bootm_size" 4854 environment variable. Address defined by "bootm_low" is 4855 also the base of the initial memory mapping for the Linux 4856 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 4857 bootm_mapsize. 4858 4859 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 4860 This variable is given as a hexadecimal number and it 4861 defines the size of the memory region starting at base 4862 address bootm_low that is accessible by the Linux kernel 4863 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 4864 as the default value if it is defined, and bootm_size is 4865 used otherwise. 4866 4867 bootm_size - Memory range available for image processing in the bootm 4868 command can be restricted. This variable is given as 4869 a hexadecimal number and defines the size of the region 4870 allowed for use by the bootm command. See also "bootm_low" 4871 environment variable. 4872 4873 updatefile - Location of the software update file on a TFTP server, used 4874 by the automatic software update feature. Please refer to 4875 documentation in doc/README.update for more details. 4876 4877 autoload - if set to "no" (any string beginning with 'n'), 4878 "bootp" will just load perform a lookup of the 4879 configuration from the BOOTP server, but not try to 4880 load any image using TFTP 4881 4882 autostart - if set to "yes", an image loaded using the "bootp", 4883 "rarpboot", "tftpboot" or "diskboot" commands will 4884 be automatically started (by internally calling 4885 "bootm") 4886 4887 If set to "no", a standalone image passed to the 4888 "bootm" command will be copied to the load address 4889 (and eventually uncompressed), but NOT be started. 4890 This can be used to load and uncompress arbitrary 4891 data. 4892 4893 fdt_high - if set this restricts the maximum address that the 4894 flattened device tree will be copied into upon boot. 4895 For example, if you have a system with 1 GB memory 4896 at physical address 0x10000000, while Linux kernel 4897 only recognizes the first 704 MB as low memory, you 4898 may need to set fdt_high as 0x3C000000 to have the 4899 device tree blob be copied to the maximum address 4900 of the 704 MB low memory, so that Linux kernel can 4901 access it during the boot procedure. 4902 4903 If this is set to the special value 0xFFFFFFFF then 4904 the fdt will not be copied at all on boot. For this 4905 to work it must reside in writable memory, have 4906 sufficient padding on the end of it for u-boot to 4907 add the information it needs into it, and the memory 4908 must be accessible by the kernel. 4909 4910 fdtcontroladdr- if set this is the address of the control flattened 4911 device tree used by U-Boot when CONFIG_OF_CONTROL is 4912 defined. 4913 4914 i2cfast - (PPC405GP|PPC405EP only) 4915 if set to 'y' configures Linux I2C driver for fast 4916 mode (400kHZ). This environment variable is used in 4917 initialization code. So, for changes to be effective 4918 it must be saved and board must be reset. 4919 4920 initrd_high - restrict positioning of initrd images: 4921 If this variable is not set, initrd images will be 4922 copied to the highest possible address in RAM; this 4923 is usually what you want since it allows for 4924 maximum initrd size. If for some reason you want to 4925 make sure that the initrd image is loaded below the 4926 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 4927 variable to a value of "no" or "off" or "0". 4928 Alternatively, you can set it to a maximum upper 4929 address to use (U-Boot will still check that it 4930 does not overwrite the U-Boot stack and data). 4931 4932 For instance, when you have a system with 16 MB 4933 RAM, and want to reserve 4 MB from use by Linux, 4934 you can do this by adding "mem=12M" to the value of 4935 the "bootargs" variable. However, now you must make 4936 sure that the initrd image is placed in the first 4937 12 MB as well - this can be done with 4938 4939 setenv initrd_high 00c00000 4940 4941 If you set initrd_high to 0xFFFFFFFF, this is an 4942 indication to U-Boot that all addresses are legal 4943 for the Linux kernel, including addresses in flash 4944 memory. In this case U-Boot will NOT COPY the 4945 ramdisk at all. This may be useful to reduce the 4946 boot time on your system, but requires that this 4947 feature is supported by your Linux kernel. 4948 4949 ipaddr - IP address; needed for tftpboot command 4950 4951 loadaddr - Default load address for commands like "bootp", 4952 "rarpboot", "tftpboot", "loadb" or "diskboot" 4953 4954 loads_echo - see CONFIG_LOADS_ECHO 4955 4956 serverip - TFTP server IP address; needed for tftpboot command 4957 4958 bootretry - see CONFIG_BOOT_RETRY_TIME 4959 4960 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 4961 4962 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 4963 4964 ethprime - controls which interface is used first. 4965 4966 ethact - controls which interface is currently active. 4967 For example you can do the following 4968 4969 => setenv ethact FEC 4970 => ping 192.168.0.1 # traffic sent on FEC 4971 => setenv ethact SCC 4972 => ping 10.0.0.1 # traffic sent on SCC 4973 4974 ethrotate - When set to "no" U-Boot does not go through all 4975 available network interfaces. 4976 It just stays at the currently selected interface. 4977 4978 netretry - When set to "no" each network operation will 4979 either succeed or fail without retrying. 4980 When set to "once" the network operation will 4981 fail when all the available network interfaces 4982 are tried once without success. 4983 Useful on scripts which control the retry operation 4984 themselves. 4985 4986 npe_ucode - set load address for the NPE microcode 4987 4988 silent_linux - If set then Linux will be told to boot silently, by 4989 changing the console to be empty. If "yes" it will be 4990 made silent. If "no" it will not be made silent. If 4991 unset, then it will be made silent if the U-Boot console 4992 is silent. 4993 4994 tftpsrcp - If this is set, the value is used for TFTP's 4995 UDP source port. 4996 4997 tftpdstp - If this is set, the value is used for TFTP's UDP 4998 destination port instead of the Well Know Port 69. 4999 5000 tftpblocksize - Block size to use for TFTP transfers; if not set, 5001 we use the TFTP server's default block size 5002 5003 tftptimeout - Retransmission timeout for TFTP packets (in milli- 5004 seconds, minimum value is 1000 = 1 second). Defines 5005 when a packet is considered to be lost so it has to 5006 be retransmitted. The default is 5000 = 5 seconds. 5007 Lowering this value may make downloads succeed 5008 faster in networks with high packet loss rates or 5009 with unreliable TFTP servers. 5010 5011 tftptimeoutcountmax - maximum count of TFTP timeouts (no 5012 unit, minimum value = 0). Defines how many timeouts 5013 can happen during a single file transfer before that 5014 transfer is aborted. The default is 10, and 0 means 5015 'no timeouts allowed'. Increasing this value may help 5016 downloads succeed with high packet loss rates, or with 5017 unreliable TFTP servers or client hardware. 5018 5019 vlan - When set to a value < 4095 the traffic over 5020 Ethernet is encapsulated/received over 802.1q 5021 VLAN tagged frames. 5022 5023 bootpretryperiod - Period during which BOOTP/DHCP sends retries. 5024 Unsigned value, in milliseconds. If not set, the period will 5025 be either the default (28000), or a value based on 5026 CONFIG_NET_RETRY_COUNT, if defined. This value has 5027 precedence over the valu based on CONFIG_NET_RETRY_COUNT. 5028 5029The following image location variables contain the location of images 5030used in booting. The "Image" column gives the role of the image and is 5031not an environment variable name. The other columns are environment 5032variable names. "File Name" gives the name of the file on a TFTP 5033server, "RAM Address" gives the location in RAM the image will be 5034loaded to, and "Flash Location" gives the image's address in NOR 5035flash or offset in NAND flash. 5036 5037*Note* - these variables don't have to be defined for all boards, some 5038boards currently use other variables for these purposes, and some 5039boards use these variables for other purposes. 5040 5041Image File Name RAM Address Flash Location 5042----- --------- ----------- -------------- 5043u-boot u-boot u-boot_addr_r u-boot_addr 5044Linux kernel bootfile kernel_addr_r kernel_addr 5045device tree blob fdtfile fdt_addr_r fdt_addr 5046ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 5047 5048The following environment variables may be used and automatically 5049updated by the network boot commands ("bootp" and "rarpboot"), 5050depending the information provided by your boot server: 5051 5052 bootfile - see above 5053 dnsip - IP address of your Domain Name Server 5054 dnsip2 - IP address of your secondary Domain Name Server 5055 gatewayip - IP address of the Gateway (Router) to use 5056 hostname - Target hostname 5057 ipaddr - see above 5058 netmask - Subnet Mask 5059 rootpath - Pathname of the root filesystem on the NFS server 5060 serverip - see above 5061 5062 5063There are two special Environment Variables: 5064 5065 serial# - contains hardware identification information such 5066 as type string and/or serial number 5067 ethaddr - Ethernet address 5068 5069These variables can be set only once (usually during manufacturing of 5070the board). U-Boot refuses to delete or overwrite these variables 5071once they have been set once. 5072 5073 5074Further special Environment Variables: 5075 5076 ver - Contains the U-Boot version string as printed 5077 with the "version" command. This variable is 5078 readonly (see CONFIG_VERSION_VARIABLE). 5079 5080 5081Please note that changes to some configuration parameters may take 5082only effect after the next boot (yes, that's just like Windoze :-). 5083 5084 5085Callback functions for environment variables: 5086--------------------------------------------- 5087 5088For some environment variables, the behavior of u-boot needs to change 5089when their values are changed. This functionality allows functions to 5090be associated with arbitrary variables. On creation, overwrite, or 5091deletion, the callback will provide the opportunity for some side 5092effect to happen or for the change to be rejected. 5093 5094The callbacks are named and associated with a function using the 5095U_BOOT_ENV_CALLBACK macro in your board or driver code. 5096 5097These callbacks are associated with variables in one of two ways. The 5098static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC 5099in the board configuration to a string that defines a list of 5100associations. The list must be in the following format: 5101 5102 entry = variable_name[:callback_name] 5103 list = entry[,list] 5104 5105If the callback name is not specified, then the callback is deleted. 5106Spaces are also allowed anywhere in the list. 5107 5108Callbacks can also be associated by defining the ".callbacks" variable 5109with the same list format above. Any association in ".callbacks" will 5110override any association in the static list. You can define 5111CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the 5112".callbacks" environment variable in the default or embedded environment. 5113 5114If CONFIG_REGEX is defined, the variable_name above is evaluated as a 5115regular expression. This allows multiple variables to be connected to 5116the same callback without explicitly listing them all out. 5117 5118 5119Command Line Parsing: 5120===================== 5121 5122There are two different command line parsers available with U-Boot: 5123the old "simple" one, and the much more powerful "hush" shell: 5124 5125Old, simple command line parser: 5126-------------------------------- 5127 5128- supports environment variables (through setenv / saveenv commands) 5129- several commands on one line, separated by ';' 5130- variable substitution using "... ${name} ..." syntax 5131- special characters ('$', ';') can be escaped by prefixing with '\', 5132 for example: 5133 setenv bootcmd bootm \${address} 5134- You can also escape text by enclosing in single apostrophes, for example: 5135 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 5136 5137Hush shell: 5138----------- 5139 5140- similar to Bourne shell, with control structures like 5141 if...then...else...fi, for...do...done; while...do...done, 5142 until...do...done, ... 5143- supports environment ("global") variables (through setenv / saveenv 5144 commands) and local shell variables (through standard shell syntax 5145 "name=value"); only environment variables can be used with "run" 5146 command 5147 5148General rules: 5149-------------- 5150 5151(1) If a command line (or an environment variable executed by a "run" 5152 command) contains several commands separated by semicolon, and 5153 one of these commands fails, then the remaining commands will be 5154 executed anyway. 5155 5156(2) If you execute several variables with one call to run (i. e. 5157 calling run with a list of variables as arguments), any failing 5158 command will cause "run" to terminate, i. e. the remaining 5159 variables are not executed. 5160 5161Note for Redundant Ethernet Interfaces: 5162======================================= 5163 5164Some boards come with redundant Ethernet interfaces; U-Boot supports 5165such configurations and is capable of automatic selection of a 5166"working" interface when needed. MAC assignment works as follows: 5167 5168Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 5169MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 5170"eth1addr" (=>eth1), "eth2addr", ... 5171 5172If the network interface stores some valid MAC address (for instance 5173in SROM), this is used as default address if there is NO correspon- 5174ding setting in the environment; if the corresponding environment 5175variable is set, this overrides the settings in the card; that means: 5176 5177o If the SROM has a valid MAC address, and there is no address in the 5178 environment, the SROM's address is used. 5179 5180o If there is no valid address in the SROM, and a definition in the 5181 environment exists, then the value from the environment variable is 5182 used. 5183 5184o If both the SROM and the environment contain a MAC address, and 5185 both addresses are the same, this MAC address is used. 5186 5187o If both the SROM and the environment contain a MAC address, and the 5188 addresses differ, the value from the environment is used and a 5189 warning is printed. 5190 5191o If neither SROM nor the environment contain a MAC address, an error 5192 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case 5193 a random, locally-assigned MAC is used. 5194 5195If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 5196will be programmed into hardware as part of the initialization process. This 5197may be skipped by setting the appropriate 'ethmacskip' environment variable. 5198The naming convention is as follows: 5199"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 5200 5201Image Formats: 5202============== 5203 5204U-Boot is capable of booting (and performing other auxiliary operations on) 5205images in two formats: 5206 5207New uImage format (FIT) 5208----------------------- 5209 5210Flexible and powerful format based on Flattened Image Tree -- FIT (similar 5211to Flattened Device Tree). It allows the use of images with multiple 5212components (several kernels, ramdisks, etc.), with contents protected by 5213SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 5214 5215 5216Old uImage format 5217----------------- 5218 5219Old image format is based on binary files which can be basically anything, 5220preceded by a special header; see the definitions in include/image.h for 5221details; basically, the header defines the following image properties: 5222 5223* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 5224 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 5225 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 5226 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 5227 INTEGRITY). 5228* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 5229 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 5230 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 5231* Compression Type (uncompressed, gzip, bzip2) 5232* Load Address 5233* Entry Point 5234* Image Name 5235* Image Timestamp 5236 5237The header is marked by a special Magic Number, and both the header 5238and the data portions of the image are secured against corruption by 5239CRC32 checksums. 5240 5241 5242Linux Support: 5243============== 5244 5245Although U-Boot should support any OS or standalone application 5246easily, the main focus has always been on Linux during the design of 5247U-Boot. 5248 5249U-Boot includes many features that so far have been part of some 5250special "boot loader" code within the Linux kernel. Also, any 5251"initrd" images to be used are no longer part of one big Linux image; 5252instead, kernel and "initrd" are separate images. This implementation 5253serves several purposes: 5254 5255- the same features can be used for other OS or standalone 5256 applications (for instance: using compressed images to reduce the 5257 Flash memory footprint) 5258 5259- it becomes much easier to port new Linux kernel versions because 5260 lots of low-level, hardware dependent stuff are done by U-Boot 5261 5262- the same Linux kernel image can now be used with different "initrd" 5263 images; of course this also means that different kernel images can 5264 be run with the same "initrd". This makes testing easier (you don't 5265 have to build a new "zImage.initrd" Linux image when you just 5266 change a file in your "initrd"). Also, a field-upgrade of the 5267 software is easier now. 5268 5269 5270Linux HOWTO: 5271============ 5272 5273Porting Linux to U-Boot based systems: 5274--------------------------------------- 5275 5276U-Boot cannot save you from doing all the necessary modifications to 5277configure the Linux device drivers for use with your target hardware 5278(no, we don't intend to provide a full virtual machine interface to 5279Linux :-). 5280 5281But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 5282 5283Just make sure your machine specific header file (for instance 5284include/asm-ppc/tqm8xx.h) includes the same definition of the Board 5285Information structure as we define in include/asm-<arch>/u-boot.h, 5286and make sure that your definition of IMAP_ADDR uses the same value 5287as your U-Boot configuration in CONFIG_SYS_IMMR. 5288 5289Note that U-Boot now has a driver model, a unified model for drivers. 5290If you are adding a new driver, plumb it into driver model. If there 5291is no uclass available, you are encouraged to create one. See 5292doc/driver-model. 5293 5294 5295Configuring the Linux kernel: 5296----------------------------- 5297 5298No specific requirements for U-Boot. Make sure you have some root 5299device (initial ramdisk, NFS) for your target system. 5300 5301 5302Building a Linux Image: 5303----------------------- 5304 5305With U-Boot, "normal" build targets like "zImage" or "bzImage" are 5306not used. If you use recent kernel source, a new build target 5307"uImage" will exist which automatically builds an image usable by 5308U-Boot. Most older kernels also have support for a "pImage" target, 5309which was introduced for our predecessor project PPCBoot and uses a 5310100% compatible format. 5311 5312Example: 5313 5314 make TQM850L_defconfig 5315 make oldconfig 5316 make dep 5317 make uImage 5318 5319The "uImage" build target uses a special tool (in 'tools/mkimage') to 5320encapsulate a compressed Linux kernel image with header information, 5321CRC32 checksum etc. for use with U-Boot. This is what we are doing: 5322 5323* build a standard "vmlinux" kernel image (in ELF binary format): 5324 5325* convert the kernel into a raw binary image: 5326 5327 ${CROSS_COMPILE}-objcopy -O binary \ 5328 -R .note -R .comment \ 5329 -S vmlinux linux.bin 5330 5331* compress the binary image: 5332 5333 gzip -9 linux.bin 5334 5335* package compressed binary image for U-Boot: 5336 5337 mkimage -A ppc -O linux -T kernel -C gzip \ 5338 -a 0 -e 0 -n "Linux Kernel Image" \ 5339 -d linux.bin.gz uImage 5340 5341 5342The "mkimage" tool can also be used to create ramdisk images for use 5343with U-Boot, either separated from the Linux kernel image, or 5344combined into one file. "mkimage" encapsulates the images with a 64 5345byte header containing information about target architecture, 5346operating system, image type, compression method, entry points, time 5347stamp, CRC32 checksums, etc. 5348 5349"mkimage" can be called in two ways: to verify existing images and 5350print the header information, or to build new images. 5351 5352In the first form (with "-l" option) mkimage lists the information 5353contained in the header of an existing U-Boot image; this includes 5354checksum verification: 5355 5356 tools/mkimage -l image 5357 -l ==> list image header information 5358 5359The second form (with "-d" option) is used to build a U-Boot image 5360from a "data file" which is used as image payload: 5361 5362 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 5363 -n name -d data_file image 5364 -A ==> set architecture to 'arch' 5365 -O ==> set operating system to 'os' 5366 -T ==> set image type to 'type' 5367 -C ==> set compression type 'comp' 5368 -a ==> set load address to 'addr' (hex) 5369 -e ==> set entry point to 'ep' (hex) 5370 -n ==> set image name to 'name' 5371 -d ==> use image data from 'datafile' 5372 5373Right now, all Linux kernels for PowerPC systems use the same load 5374address (0x00000000), but the entry point address depends on the 5375kernel version: 5376 5377- 2.2.x kernels have the entry point at 0x0000000C, 5378- 2.3.x and later kernels have the entry point at 0x00000000. 5379 5380So a typical call to build a U-Boot image would read: 5381 5382 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5383 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 5384 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 5385 > examples/uImage.TQM850L 5386 Image Name: 2.4.4 kernel for TQM850L 5387 Created: Wed Jul 19 02:34:59 2000 5388 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5389 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5390 Load Address: 0x00000000 5391 Entry Point: 0x00000000 5392 5393To verify the contents of the image (or check for corruption): 5394 5395 -> tools/mkimage -l examples/uImage.TQM850L 5396 Image Name: 2.4.4 kernel for TQM850L 5397 Created: Wed Jul 19 02:34:59 2000 5398 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5399 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5400 Load Address: 0x00000000 5401 Entry Point: 0x00000000 5402 5403NOTE: for embedded systems where boot time is critical you can trade 5404speed for memory and install an UNCOMPRESSED image instead: this 5405needs more space in Flash, but boots much faster since it does not 5406need to be uncompressed: 5407 5408 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 5409 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5410 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 5411 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 5412 > examples/uImage.TQM850L-uncompressed 5413 Image Name: 2.4.4 kernel for TQM850L 5414 Created: Wed Jul 19 02:34:59 2000 5415 Image Type: PowerPC Linux Kernel Image (uncompressed) 5416 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 5417 Load Address: 0x00000000 5418 Entry Point: 0x00000000 5419 5420 5421Similar you can build U-Boot images from a 'ramdisk.image.gz' file 5422when your kernel is intended to use an initial ramdisk: 5423 5424 -> tools/mkimage -n 'Simple Ramdisk Image' \ 5425 > -A ppc -O linux -T ramdisk -C gzip \ 5426 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 5427 Image Name: Simple Ramdisk Image 5428 Created: Wed Jan 12 14:01:50 2000 5429 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5430 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 5431 Load Address: 0x00000000 5432 Entry Point: 0x00000000 5433 5434The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i" 5435option performs the converse operation of the mkimage's second form (the "-d" 5436option). Given an image built by mkimage, the dumpimage extracts a "data file" 5437from the image: 5438 5439 tools/dumpimage -i image -T type -p position data_file 5440 -i ==> extract from the 'image' a specific 'data_file' 5441 -T ==> set image type to 'type' 5442 -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image' 5443 5444 5445Installing a Linux Image: 5446------------------------- 5447 5448To downloading a U-Boot image over the serial (console) interface, 5449you must convert the image to S-Record format: 5450 5451 objcopy -I binary -O srec examples/image examples/image.srec 5452 5453The 'objcopy' does not understand the information in the U-Boot 5454image header, so the resulting S-Record file will be relative to 5455address 0x00000000. To load it to a given address, you need to 5456specify the target address as 'offset' parameter with the 'loads' 5457command. 5458 5459Example: install the image to address 0x40100000 (which on the 5460TQM8xxL is in the first Flash bank): 5461 5462 => erase 40100000 401FFFFF 5463 5464 .......... done 5465 Erased 8 sectors 5466 5467 => loads 40100000 5468 ## Ready for S-Record download ... 5469 ~>examples/image.srec 5470 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 5471 ... 5472 15989 15990 15991 15992 5473 [file transfer complete] 5474 [connected] 5475 ## Start Addr = 0x00000000 5476 5477 5478You can check the success of the download using the 'iminfo' command; 5479this includes a checksum verification so you can be sure no data 5480corruption happened: 5481 5482 => imi 40100000 5483 5484 ## Checking Image at 40100000 ... 5485 Image Name: 2.2.13 for initrd on TQM850L 5486 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5487 Data Size: 335725 Bytes = 327 kB = 0 MB 5488 Load Address: 00000000 5489 Entry Point: 0000000c 5490 Verifying Checksum ... OK 5491 5492 5493Boot Linux: 5494----------- 5495 5496The "bootm" command is used to boot an application that is stored in 5497memory (RAM or Flash). In case of a Linux kernel image, the contents 5498of the "bootargs" environment variable is passed to the kernel as 5499parameters. You can check and modify this variable using the 5500"printenv" and "setenv" commands: 5501 5502 5503 => printenv bootargs 5504 bootargs=root=/dev/ram 5505 5506 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5507 5508 => printenv bootargs 5509 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5510 5511 => bootm 40020000 5512 ## Booting Linux kernel at 40020000 ... 5513 Image Name: 2.2.13 for NFS on TQM850L 5514 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5515 Data Size: 381681 Bytes = 372 kB = 0 MB 5516 Load Address: 00000000 5517 Entry Point: 0000000c 5518 Verifying Checksum ... OK 5519 Uncompressing Kernel Image ... OK 5520 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 5521 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5522 time_init: decrementer frequency = 187500000/60 5523 Calibrating delay loop... 49.77 BogoMIPS 5524 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 5525 ... 5526 5527If you want to boot a Linux kernel with initial RAM disk, you pass 5528the memory addresses of both the kernel and the initrd image (PPBCOOT 5529format!) to the "bootm" command: 5530 5531 => imi 40100000 40200000 5532 5533 ## Checking Image at 40100000 ... 5534 Image Name: 2.2.13 for initrd on TQM850L 5535 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5536 Data Size: 335725 Bytes = 327 kB = 0 MB 5537 Load Address: 00000000 5538 Entry Point: 0000000c 5539 Verifying Checksum ... OK 5540 5541 ## Checking Image at 40200000 ... 5542 Image Name: Simple Ramdisk Image 5543 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5544 Data Size: 566530 Bytes = 553 kB = 0 MB 5545 Load Address: 00000000 5546 Entry Point: 00000000 5547 Verifying Checksum ... OK 5548 5549 => bootm 40100000 40200000 5550 ## Booting Linux kernel at 40100000 ... 5551 Image Name: 2.2.13 for initrd on TQM850L 5552 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5553 Data Size: 335725 Bytes = 327 kB = 0 MB 5554 Load Address: 00000000 5555 Entry Point: 0000000c 5556 Verifying Checksum ... OK 5557 Uncompressing Kernel Image ... OK 5558 ## Loading RAMDisk Image at 40200000 ... 5559 Image Name: Simple Ramdisk Image 5560 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5561 Data Size: 566530 Bytes = 553 kB = 0 MB 5562 Load Address: 00000000 5563 Entry Point: 00000000 5564 Verifying Checksum ... OK 5565 Loading Ramdisk ... OK 5566 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 5567 Boot arguments: root=/dev/ram 5568 time_init: decrementer frequency = 187500000/60 5569 Calibrating delay loop... 49.77 BogoMIPS 5570 ... 5571 RAMDISK: Compressed image found at block 0 5572 VFS: Mounted root (ext2 filesystem). 5573 5574 bash# 5575 5576Boot Linux and pass a flat device tree: 5577----------- 5578 5579First, U-Boot must be compiled with the appropriate defines. See the section 5580titled "Linux Kernel Interface" above for a more in depth explanation. The 5581following is an example of how to start a kernel and pass an updated 5582flat device tree: 5583 5584=> print oftaddr 5585oftaddr=0x300000 5586=> print oft 5587oft=oftrees/mpc8540ads.dtb 5588=> tftp $oftaddr $oft 5589Speed: 1000, full duplex 5590Using TSEC0 device 5591TFTP from server 192.168.1.1; our IP address is 192.168.1.101 5592Filename 'oftrees/mpc8540ads.dtb'. 5593Load address: 0x300000 5594Loading: # 5595done 5596Bytes transferred = 4106 (100a hex) 5597=> tftp $loadaddr $bootfile 5598Speed: 1000, full duplex 5599Using TSEC0 device 5600TFTP from server 192.168.1.1; our IP address is 192.168.1.2 5601Filename 'uImage'. 5602Load address: 0x200000 5603Loading:############ 5604done 5605Bytes transferred = 1029407 (fb51f hex) 5606=> print loadaddr 5607loadaddr=200000 5608=> print oftaddr 5609oftaddr=0x300000 5610=> bootm $loadaddr - $oftaddr 5611## Booting image at 00200000 ... 5612 Image Name: Linux-2.6.17-dirty 5613 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5614 Data Size: 1029343 Bytes = 1005.2 kB 5615 Load Address: 00000000 5616 Entry Point: 00000000 5617 Verifying Checksum ... OK 5618 Uncompressing Kernel Image ... OK 5619Booting using flat device tree at 0x300000 5620Using MPC85xx ADS machine description 5621Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 5622[snip] 5623 5624 5625More About U-Boot Image Types: 5626------------------------------ 5627 5628U-Boot supports the following image types: 5629 5630 "Standalone Programs" are directly runnable in the environment 5631 provided by U-Boot; it is expected that (if they behave 5632 well) you can continue to work in U-Boot after return from 5633 the Standalone Program. 5634 "OS Kernel Images" are usually images of some Embedded OS which 5635 will take over control completely. Usually these programs 5636 will install their own set of exception handlers, device 5637 drivers, set up the MMU, etc. - this means, that you cannot 5638 expect to re-enter U-Boot except by resetting the CPU. 5639 "RAMDisk Images" are more or less just data blocks, and their 5640 parameters (address, size) are passed to an OS kernel that is 5641 being started. 5642 "Multi-File Images" contain several images, typically an OS 5643 (Linux) kernel image and one or more data images like 5644 RAMDisks. This construct is useful for instance when you want 5645 to boot over the network using BOOTP etc., where the boot 5646 server provides just a single image file, but you want to get 5647 for instance an OS kernel and a RAMDisk image. 5648 5649 "Multi-File Images" start with a list of image sizes, each 5650 image size (in bytes) specified by an "uint32_t" in network 5651 byte order. This list is terminated by an "(uint32_t)0". 5652 Immediately after the terminating 0 follow the images, one by 5653 one, all aligned on "uint32_t" boundaries (size rounded up to 5654 a multiple of 4 bytes). 5655 5656 "Firmware Images" are binary images containing firmware (like 5657 U-Boot or FPGA images) which usually will be programmed to 5658 flash memory. 5659 5660 "Script files" are command sequences that will be executed by 5661 U-Boot's command interpreter; this feature is especially 5662 useful when you configure U-Boot to use a real shell (hush) 5663 as command interpreter. 5664 5665Booting the Linux zImage: 5666------------------------- 5667 5668On some platforms, it's possible to boot Linux zImage. This is done 5669using the "bootz" command. The syntax of "bootz" command is the same 5670as the syntax of "bootm" command. 5671 5672Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply 5673kernel with raw initrd images. The syntax is slightly different, the 5674address of the initrd must be augmented by it's size, in the following 5675format: "<initrd addres>:<initrd size>". 5676 5677 5678Standalone HOWTO: 5679================= 5680 5681One of the features of U-Boot is that you can dynamically load and 5682run "standalone" applications, which can use some resources of 5683U-Boot like console I/O functions or interrupt services. 5684 5685Two simple examples are included with the sources: 5686 5687"Hello World" Demo: 5688------------------- 5689 5690'examples/hello_world.c' contains a small "Hello World" Demo 5691application; it is automatically compiled when you build U-Boot. 5692It's configured to run at address 0x00040004, so you can play with it 5693like that: 5694 5695 => loads 5696 ## Ready for S-Record download ... 5697 ~>examples/hello_world.srec 5698 1 2 3 4 5 6 7 8 9 10 11 ... 5699 [file transfer complete] 5700 [connected] 5701 ## Start Addr = 0x00040004 5702 5703 => go 40004 Hello World! This is a test. 5704 ## Starting application at 0x00040004 ... 5705 Hello World 5706 argc = 7 5707 argv[0] = "40004" 5708 argv[1] = "Hello" 5709 argv[2] = "World!" 5710 argv[3] = "This" 5711 argv[4] = "is" 5712 argv[5] = "a" 5713 argv[6] = "test." 5714 argv[7] = "<NULL>" 5715 Hit any key to exit ... 5716 5717 ## Application terminated, rc = 0x0 5718 5719Another example, which demonstrates how to register a CPM interrupt 5720handler with the U-Boot code, can be found in 'examples/timer.c'. 5721Here, a CPM timer is set up to generate an interrupt every second. 5722The interrupt service routine is trivial, just printing a '.' 5723character, but this is just a demo program. The application can be 5724controlled by the following keys: 5725 5726 ? - print current values og the CPM Timer registers 5727 b - enable interrupts and start timer 5728 e - stop timer and disable interrupts 5729 q - quit application 5730 5731 => loads 5732 ## Ready for S-Record download ... 5733 ~>examples/timer.srec 5734 1 2 3 4 5 6 7 8 9 10 11 ... 5735 [file transfer complete] 5736 [connected] 5737 ## Start Addr = 0x00040004 5738 5739 => go 40004 5740 ## Starting application at 0x00040004 ... 5741 TIMERS=0xfff00980 5742 Using timer 1 5743 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 5744 5745Hit 'b': 5746 [q, b, e, ?] Set interval 1000000 us 5747 Enabling timer 5748Hit '?': 5749 [q, b, e, ?] ........ 5750 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 5751Hit '?': 5752 [q, b, e, ?] . 5753 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 5754Hit '?': 5755 [q, b, e, ?] . 5756 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 5757Hit '?': 5758 [q, b, e, ?] . 5759 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 5760Hit 'e': 5761 [q, b, e, ?] ...Stopping timer 5762Hit 'q': 5763 [q, b, e, ?] ## Application terminated, rc = 0x0 5764 5765 5766Minicom warning: 5767================ 5768 5769Over time, many people have reported problems when trying to use the 5770"minicom" terminal emulation program for serial download. I (wd) 5771consider minicom to be broken, and recommend not to use it. Under 5772Unix, I recommend to use C-Kermit for general purpose use (and 5773especially for kermit binary protocol download ("loadb" command), and 5774use "cu" for S-Record download ("loads" command). See 5775http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3. 5776for help with kermit. 5777 5778 5779Nevertheless, if you absolutely want to use it try adding this 5780configuration to your "File transfer protocols" section: 5781 5782 Name Program Name U/D FullScr IO-Red. Multi 5783 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 5784 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 5785 5786 5787NetBSD Notes: 5788============= 5789 5790Starting at version 0.9.2, U-Boot supports NetBSD both as host 5791(build U-Boot) and target system (boots NetBSD/mpc8xx). 5792 5793Building requires a cross environment; it is known to work on 5794NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 5795need gmake since the Makefiles are not compatible with BSD make). 5796Note that the cross-powerpc package does not install include files; 5797attempting to build U-Boot will fail because <machine/ansi.h> is 5798missing. This file has to be installed and patched manually: 5799 5800 # cd /usr/pkg/cross/powerpc-netbsd/include 5801 # mkdir powerpc 5802 # ln -s powerpc machine 5803 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 5804 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 5805 5806Native builds *don't* work due to incompatibilities between native 5807and U-Boot include files. 5808 5809Booting assumes that (the first part of) the image booted is a 5810stage-2 loader which in turn loads and then invokes the kernel 5811proper. Loader sources will eventually appear in the NetBSD source 5812tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 5813meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 5814 5815 5816Implementation Internals: 5817========================= 5818 5819The following is not intended to be a complete description of every 5820implementation detail. However, it should help to understand the 5821inner workings of U-Boot and make it easier to port it to custom 5822hardware. 5823 5824 5825Initial Stack, Global Data: 5826--------------------------- 5827 5828The implementation of U-Boot is complicated by the fact that U-Boot 5829starts running out of ROM (flash memory), usually without access to 5830system RAM (because the memory controller is not initialized yet). 5831This means that we don't have writable Data or BSS segments, and BSS 5832is not initialized as zero. To be able to get a C environment working 5833at all, we have to allocate at least a minimal stack. Implementation 5834options for this are defined and restricted by the CPU used: Some CPU 5835models provide on-chip memory (like the IMMR area on MPC8xx and 5836MPC826x processors), on others (parts of) the data cache can be 5837locked as (mis-) used as memory, etc. 5838 5839 Chris Hallinan posted a good summary of these issues to the 5840 U-Boot mailing list: 5841 5842 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 5843 From: "Chris Hallinan" <clh@net1plus.com> 5844 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 5845 ... 5846 5847 Correct me if I'm wrong, folks, but the way I understand it 5848 is this: Using DCACHE as initial RAM for Stack, etc, does not 5849 require any physical RAM backing up the cache. The cleverness 5850 is that the cache is being used as a temporary supply of 5851 necessary storage before the SDRAM controller is setup. It's 5852 beyond the scope of this list to explain the details, but you 5853 can see how this works by studying the cache architecture and 5854 operation in the architecture and processor-specific manuals. 5855 5856 OCM is On Chip Memory, which I believe the 405GP has 4K. It 5857 is another option for the system designer to use as an 5858 initial stack/RAM area prior to SDRAM being available. Either 5859 option should work for you. Using CS 4 should be fine if your 5860 board designers haven't used it for something that would 5861 cause you grief during the initial boot! It is frequently not 5862 used. 5863 5864 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 5865 with your processor/board/system design. The default value 5866 you will find in any recent u-boot distribution in 5867 walnut.h should work for you. I'd set it to a value larger 5868 than your SDRAM module. If you have a 64MB SDRAM module, set 5869 it above 400_0000. Just make sure your board has no resources 5870 that are supposed to respond to that address! That code in 5871 start.S has been around a while and should work as is when 5872 you get the config right. 5873 5874 -Chris Hallinan 5875 DS4.COM, Inc. 5876 5877It is essential to remember this, since it has some impact on the C 5878code for the initialization procedures: 5879 5880* Initialized global data (data segment) is read-only. Do not attempt 5881 to write it. 5882 5883* Do not use any uninitialized global data (or implicitly initialized 5884 as zero data - BSS segment) at all - this is undefined, initiali- 5885 zation is performed later (when relocating to RAM). 5886 5887* Stack space is very limited. Avoid big data buffers or things like 5888 that. 5889 5890Having only the stack as writable memory limits means we cannot use 5891normal global data to share information between the code. But it 5892turned out that the implementation of U-Boot can be greatly 5893simplified by making a global data structure (gd_t) available to all 5894functions. We could pass a pointer to this data as argument to _all_ 5895functions, but this would bloat the code. Instead we use a feature of 5896the GCC compiler (Global Register Variables) to share the data: we 5897place a pointer (gd) to the global data into a register which we 5898reserve for this purpose. 5899 5900When choosing a register for such a purpose we are restricted by the 5901relevant (E)ABI specifications for the current architecture, and by 5902GCC's implementation. 5903 5904For PowerPC, the following registers have specific use: 5905 R1: stack pointer 5906 R2: reserved for system use 5907 R3-R4: parameter passing and return values 5908 R5-R10: parameter passing 5909 R13: small data area pointer 5910 R30: GOT pointer 5911 R31: frame pointer 5912 5913 (U-Boot also uses R12 as internal GOT pointer. r12 5914 is a volatile register so r12 needs to be reset when 5915 going back and forth between asm and C) 5916 5917 ==> U-Boot will use R2 to hold a pointer to the global data 5918 5919 Note: on PPC, we could use a static initializer (since the 5920 address of the global data structure is known at compile time), 5921 but it turned out that reserving a register results in somewhat 5922 smaller code - although the code savings are not that big (on 5923 average for all boards 752 bytes for the whole U-Boot image, 5924 624 text + 127 data). 5925 5926On Blackfin, the normal C ABI (except for P3) is followed as documented here: 5927 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 5928 5929 ==> U-Boot will use P3 to hold a pointer to the global data 5930 5931On ARM, the following registers are used: 5932 5933 R0: function argument word/integer result 5934 R1-R3: function argument word 5935 R9: platform specific 5936 R10: stack limit (used only if stack checking is enabled) 5937 R11: argument (frame) pointer 5938 R12: temporary workspace 5939 R13: stack pointer 5940 R14: link register 5941 R15: program counter 5942 5943 ==> U-Boot will use R9 to hold a pointer to the global data 5944 5945 Note: on ARM, only R_ARM_RELATIVE relocations are supported. 5946 5947On Nios II, the ABI is documented here: 5948 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 5949 5950 ==> U-Boot will use gp to hold a pointer to the global data 5951 5952 Note: on Nios II, we give "-G0" option to gcc and don't use gp 5953 to access small data sections, so gp is free. 5954 5955On NDS32, the following registers are used: 5956 5957 R0-R1: argument/return 5958 R2-R5: argument 5959 R15: temporary register for assembler 5960 R16: trampoline register 5961 R28: frame pointer (FP) 5962 R29: global pointer (GP) 5963 R30: link register (LP) 5964 R31: stack pointer (SP) 5965 PC: program counter (PC) 5966 5967 ==> U-Boot will use R10 to hold a pointer to the global data 5968 5969NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 5970or current versions of GCC may "optimize" the code too much. 5971 5972Memory Management: 5973------------------ 5974 5975U-Boot runs in system state and uses physical addresses, i.e. the 5976MMU is not used either for address mapping nor for memory protection. 5977 5978The available memory is mapped to fixed addresses using the memory 5979controller. In this process, a contiguous block is formed for each 5980memory type (Flash, SDRAM, SRAM), even when it consists of several 5981physical memory banks. 5982 5983U-Boot is installed in the first 128 kB of the first Flash bank (on 5984TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 5985booting and sizing and initializing DRAM, the code relocates itself 5986to the upper end of DRAM. Immediately below the U-Boot code some 5987memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 5988configuration setting]. Below that, a structure with global Board 5989Info data is placed, followed by the stack (growing downward). 5990 5991Additionally, some exception handler code is copied to the low 8 kB 5992of DRAM (0x00000000 ... 0x00001FFF). 5993 5994So a typical memory configuration with 16 MB of DRAM could look like 5995this: 5996 5997 0x0000 0000 Exception Vector code 5998 : 5999 0x0000 1FFF 6000 0x0000 2000 Free for Application Use 6001 : 6002 : 6003 6004 : 6005 : 6006 0x00FB FF20 Monitor Stack (Growing downward) 6007 0x00FB FFAC Board Info Data and permanent copy of global data 6008 0x00FC 0000 Malloc Arena 6009 : 6010 0x00FD FFFF 6011 0x00FE 0000 RAM Copy of Monitor Code 6012 ... eventually: LCD or video framebuffer 6013 ... eventually: pRAM (Protected RAM - unchanged by reset) 6014 0x00FF FFFF [End of RAM] 6015 6016 6017System Initialization: 6018---------------------- 6019 6020In the reset configuration, U-Boot starts at the reset entry point 6021(on most PowerPC systems at address 0x00000100). Because of the reset 6022configuration for CS0# this is a mirror of the on board Flash memory. 6023To be able to re-map memory U-Boot then jumps to its link address. 6024To be able to implement the initialization code in C, a (small!) 6025initial stack is set up in the internal Dual Ported RAM (in case CPUs 6026which provide such a feature like MPC8xx or MPC8260), or in a locked 6027part of the data cache. After that, U-Boot initializes the CPU core, 6028the caches and the SIU. 6029 6030Next, all (potentially) available memory banks are mapped using a 6031preliminary mapping. For example, we put them on 512 MB boundaries 6032(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 6033on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 6034programmed for SDRAM access. Using the temporary configuration, a 6035simple memory test is run that determines the size of the SDRAM 6036banks. 6037 6038When there is more than one SDRAM bank, and the banks are of 6039different size, the largest is mapped first. For equal size, the first 6040bank (CS2#) is mapped first. The first mapping is always for address 60410x00000000, with any additional banks following immediately to create 6042contiguous memory starting from 0. 6043 6044Then, the monitor installs itself at the upper end of the SDRAM area 6045and allocates memory for use by malloc() and for the global Board 6046Info data; also, the exception vector code is copied to the low RAM 6047pages, and the final stack is set up. 6048 6049Only after this relocation will you have a "normal" C environment; 6050until that you are restricted in several ways, mostly because you are 6051running from ROM, and because the code will have to be relocated to a 6052new address in RAM. 6053 6054 6055U-Boot Porting Guide: 6056---------------------- 6057 6058[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 6059list, October 2002] 6060 6061 6062int main(int argc, char *argv[]) 6063{ 6064 sighandler_t no_more_time; 6065 6066 signal(SIGALRM, no_more_time); 6067 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 6068 6069 if (available_money > available_manpower) { 6070 Pay consultant to port U-Boot; 6071 return 0; 6072 } 6073 6074 Download latest U-Boot source; 6075 6076 Subscribe to u-boot mailing list; 6077 6078 if (clueless) 6079 email("Hi, I am new to U-Boot, how do I get started?"); 6080 6081 while (learning) { 6082 Read the README file in the top level directory; 6083 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 6084 Read applicable doc/*.README; 6085 Read the source, Luke; 6086 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 6087 } 6088 6089 if (available_money > toLocalCurrency ($2500)) 6090 Buy a BDI3000; 6091 else 6092 Add a lot of aggravation and time; 6093 6094 if (a similar board exists) { /* hopefully... */ 6095 cp -a board/<similar> board/<myboard> 6096 cp include/configs/<similar>.h include/configs/<myboard>.h 6097 } else { 6098 Create your own board support subdirectory; 6099 Create your own board include/configs/<myboard>.h file; 6100 } 6101 Edit new board/<myboard> files 6102 Edit new include/configs/<myboard>.h 6103 6104 while (!accepted) { 6105 while (!running) { 6106 do { 6107 Add / modify source code; 6108 } until (compiles); 6109 Debug; 6110 if (clueless) 6111 email("Hi, I am having problems..."); 6112 } 6113 Send patch file to the U-Boot email list; 6114 if (reasonable critiques) 6115 Incorporate improvements from email list code review; 6116 else 6117 Defend code as written; 6118 } 6119 6120 return 0; 6121} 6122 6123void no_more_time (int sig) 6124{ 6125 hire_a_guru(); 6126} 6127 6128 6129Coding Standards: 6130----------------- 6131 6132All contributions to U-Boot should conform to the Linux kernel 6133coding style; see the file "Documentation/CodingStyle" and the script 6134"scripts/Lindent" in your Linux kernel source directory. 6135 6136Source files originating from a different project (for example the 6137MTD subsystem) are generally exempt from these guidelines and are not 6138reformatted to ease subsequent migration to newer versions of those 6139sources. 6140 6141Please note that U-Boot is implemented in C (and to some small parts in 6142Assembler); no C++ is used, so please do not use C++ style comments (//) 6143in your code. 6144 6145Please also stick to the following formatting rules: 6146- remove any trailing white space 6147- use TAB characters for indentation and vertical alignment, not spaces 6148- make sure NOT to use DOS '\r\n' line feeds 6149- do not add more than 2 consecutive empty lines to source files 6150- do not add trailing empty lines to source files 6151 6152Submissions which do not conform to the standards may be returned 6153with a request to reformat the changes. 6154 6155 6156Submitting Patches: 6157------------------- 6158 6159Since the number of patches for U-Boot is growing, we need to 6160establish some rules. Submissions which do not conform to these rules 6161may be rejected, even when they contain important and valuable stuff. 6162 6163Please see http://www.denx.de/wiki/U-Boot/Patches for details. 6164 6165Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 6166see http://lists.denx.de/mailman/listinfo/u-boot 6167 6168When you send a patch, please include the following information with 6169it: 6170 6171* For bug fixes: a description of the bug and how your patch fixes 6172 this bug. Please try to include a way of demonstrating that the 6173 patch actually fixes something. 6174 6175* For new features: a description of the feature and your 6176 implementation. 6177 6178* A CHANGELOG entry as plaintext (separate from the patch) 6179 6180* For major contributions, add a MAINTAINERS file with your 6181 information and associated file and directory references. 6182 6183* When you add support for a new board, don't forget to add a 6184 maintainer e-mail address to the boards.cfg file, too. 6185 6186* If your patch adds new configuration options, don't forget to 6187 document these in the README file. 6188 6189* The patch itself. If you are using git (which is *strongly* 6190 recommended) you can easily generate the patch using the 6191 "git format-patch". If you then use "git send-email" to send it to 6192 the U-Boot mailing list, you will avoid most of the common problems 6193 with some other mail clients. 6194 6195 If you cannot use git, use "diff -purN OLD NEW". If your version of 6196 diff does not support these options, then get the latest version of 6197 GNU diff. 6198 6199 The current directory when running this command shall be the parent 6200 directory of the U-Boot source tree (i. e. please make sure that 6201 your patch includes sufficient directory information for the 6202 affected files). 6203 6204 We prefer patches as plain text. MIME attachments are discouraged, 6205 and compressed attachments must not be used. 6206 6207* If one logical set of modifications affects or creates several 6208 files, all these changes shall be submitted in a SINGLE patch file. 6209 6210* Changesets that contain different, unrelated modifications shall be 6211 submitted as SEPARATE patches, one patch per changeset. 6212 6213 6214Notes: 6215 6216* Before sending the patch, run the buildman script on your patched 6217 source tree and make sure that no errors or warnings are reported 6218 for any of the boards. 6219 6220* Keep your modifications to the necessary minimum: A patch 6221 containing several unrelated changes or arbitrary reformats will be 6222 returned with a request to re-formatting / split it. 6223 6224* If you modify existing code, make sure that your new code does not 6225 add to the memory footprint of the code ;-) Small is beautiful! 6226 When adding new features, these should compile conditionally only 6227 (using #ifdef), and the resulting code with the new feature 6228 disabled must not need more memory than the old code without your 6229 modification. 6230 6231* Remember that there is a size limit of 100 kB per message on the 6232 u-boot mailing list. Bigger patches will be moderated. If they are 6233 reasonable and not too big, they will be acknowledged. But patches 6234 bigger than the size limit should be avoided. 6235