Status:
=======
-In general, all boards for which a configuration option exists in the
-Makefile have been tested to some extent and can be considered
+In general, all boards for which a default configuration file exists in the
+configs/ directory have been tested to some extent and can be considered
"working". In fact, many of them are used in production systems.
-In case of problems see the CHANGELOG file to find out who contributed
-the specific port. In addition, there are various MAINTAINERS files
-scattered throughout the U-Boot source identifying the people or
-companies responsible for various boards and subsystems.
+In case of problems you can use
-Note: As of August, 2010, there is no longer a CHANGELOG file in the
-actual U-Boot source tree; however, it can be created dynamically
-from the Git log using:
+ scripts/get_maintainer.pl <path>
- make CHANGELOG
+to identify the people or companies responsible for various boards and
+subsystems. Or have a look at the git log.
Where to get help:
IH_OS_U_BOOT u_boot_hush_start
-Versioning:
-===========
-
-Starting with the release in October 2008, the names of the releases
-were changed from numerical release numbers without deeper meaning
-into a time stamp based numbering. Regular releases are identified by
-names consisting of the calendar year and month of the release date.
-Additional fields (if present) indicate release candidates or bug fix
-releases in "stable" maintenance trees.
-
-Examples:
- U-Boot v2009.11 - Release November 2009
- U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
- U-Boot v2010.09-rc1 - Release candidate 1 for September 2010 release
-
-
-Directory Hierarchy:
-====================
-
-/arch Architecture-specific files
- /arc Files generic to ARC architecture
- /arm Files generic to ARM architecture
- /m68k Files generic to m68k architecture
- /microblaze Files generic to microblaze architecture
- /mips Files generic to MIPS architecture
- /nios2 Files generic to Altera NIOS2 architecture
- /powerpc Files generic to PowerPC architecture
- /riscv Files generic to RISC-V architecture
- /sandbox Files generic to HW-independent "sandbox"
- /sh Files generic to SH architecture
- /x86 Files generic to x86 architecture
- /xtensa Files generic to Xtensa architecture
-/api Machine/arch-independent API for external apps
-/board Board-dependent files
-/boot Support for images and booting
-/cmd U-Boot commands functions
-/common Misc architecture-independent functions
-/configs Board default configuration files
-/disk Code for disk drive partition handling
-/doc Documentation (a mix of ReST and READMEs)
-/drivers Device drivers
-/dts Makefile for building internal U-Boot fdt.
-/env Environment support
-/examples Example code for standalone applications, etc.
-/fs Filesystem code (cramfs, ext2, jffs2, etc.)
-/include Header Files
-/lib Library routines generic to all architectures
-/Licenses Various license files
-/net Networking code
-/post Power On Self Test
-/scripts Various build scripts and Makefiles
-/test Various unit test files
-/tools Tools to build and sign FIT images, etc.
-
Software Configuration:
=======================
specific to be undertaken on a native platform. The sandbox is also used to
run some of U-Boot's tests.
-See doc/arch/sandbox.rst for more details.
+See doc/arch/sandbox/sandbox.rst for more details.
Board Initialisation Flow:
same as CFG_SYS_DDR_SDRAM_BASE for all Power SoCs. But
it could be different for ARM SoCs.
-- MIPS CPU options:
- CONFIG_XWAY_SWAP_BYTES
-
- Enable compilation of tools/xway-swap-bytes needed for Lantiq
- XWAY SoCs for booting from NOR flash. The U-Boot image needs to
- be swapped if a flash programmer is used.
-
- ARM options:
CFG_SYS_EXCEPTION_VECTORS_HIGH
controller register space
- Serial Ports:
- CONFIG_PL011_CLOCK
+ CFG_PL011_CLOCK
If you have Amba PrimeCell PL011 UARTs, set this variable to
the clock speed of the UARTs.
- CONFIG_PL01x_PORTS
+ CFG_PL01x_PORTS
If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
define this to a list of base addresses for each (supported)
example "env grep" and "setexpr".
- Watchdog:
- CONFIG_SYS_WATCHDOG_FREQ
+ CFG_SYS_WATCHDOG_FREQ
Some platforms automatically call WATCHDOG_RESET()
from the timer interrupt handler every
- CONFIG_SYS_WATCHDOG_FREQ interrupts. If not set by the
+ CFG_SYS_WATCHDOG_FREQ interrupts. If not set by the
board configuration file, a default of CONFIG_SYS_HZ/2
- (i.e. 500) is used. Setting CONFIG_SYS_WATCHDOG_FREQ
+ (i.e. 500) is used. Setting CFG_SYS_WATCHDOG_FREQ
to 0 disables calling WATCHDOG_RESET() from the timer
interrupt.
CONFIG_LAN91C96_USE_32_BIT
Define this to enable 32 bit addressing
- CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
+ CFG_SYS_DAVINCI_EMAC_PHY_COUNT
Define this if you have more then 3 PHYs.
CONFIG_FTGMAC100
CONFIG_SH_ETHER
Support for Renesas on-chip Ethernet controller
- CONFIG_SH_ETHER_USE_PORT
+ CFG_SH_ETHER_USE_PORT
Define the number of ports to be used
- CONFIG_SH_ETHER_PHY_ADDR
+ CFG_SH_ETHER_PHY_ADDR
Define the ETH PHY's address
- CONFIG_SH_ETHER_CACHE_WRITEBACK
+ CFG_SH_ETHER_CACHE_WRITEBACK
If this option is set, the driver enables cache flush.
- TPM Support:
To enable the ULPI layer support, define CONFIG_USB_ULPI and
CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
If your ULPI phy needs a different reference clock than the
- standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
+ standard 24 MHz then you have to define CFG_ULPI_REF_CLK to
the appropriate value in Hz.
- MMC Support:
4th and following
BOOTP requests: delay 0 ... 8 sec
- CONFIG_BOOTP_ID_CACHE_SIZE
+ CFG_BOOTP_ID_CACHE_SIZE
BOOTP packets are uniquely identified using a 32-bit ID. The
server will copy the ID from client requests to responses and
time is too long, U-Boot will retransmit requests. In order
to allow earlier responses to still be accepted after these
retransmissions, U-Boot's BOOTP client keeps a small cache of
- IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this
+ IDs. The CFG_BOOTP_ID_CACHE_SIZE controls the size of this
cache. The default is to keep IDs for up to four outstanding
requests. Increasing this will allow U-Boot to accept offers
from a BOOTP client in networks with unusually high latency.
status LED backend implementation. Define CONFIG_LED_STATUS_GPIO
to include the gpio_led driver in the U-Boot binary.
- CONFIG_GPIO_LED_INVERTED_TABLE
+ CFG_GPIO_LED_INVERTED_TABLE
Some GPIO connected LEDs may have inverted polarity in which
case the GPIO high value corresponds to LED off state and
GPIO low value corresponds to LED on state.
- In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
+ In such cases CFG_GPIO_LED_INVERTED_TABLE may be defined
with a list of GPIO LEDs that have inverted polarity.
- I2C Support:
CFG_SYS_NUM_I2C_BUSES
Hold the number of i2c buses you want to use.
- CONFIG_SYS_I2C_DIRECT_BUS
+ CFG_SYS_I2C_DIRECT_BUS
define this, if you don't use i2c muxes on your hardware.
if CFG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
omit this define.
CFG_SYS_I2C_BUSES
hold a list of buses you want to use, only used if
- CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
+ CFG_SYS_I2C_DIRECT_BUS is not defined, for example
a board with CFG_SYS_I2C_MAX_HOPS = 1 and
CFG_SYS_NUM_I2C_BUSES = 9:
You should define these to the GPIO value as given directly to
the generic GPIO functions.
- CONFIG_I2C_MULTI_BUS
+ CFG_I2C_MULTI_BUS
This option allows the use of multiple I2C buses, each of which
must have a controller. At any point in time, only one bus is
SPI EEPROM, also an instance works with Crystal A/D and
D/As on the SACSng board)
- CONFIG_SYS_SPI_MXC_WAIT
+ CFG_SYS_SPI_MXC_WAIT
Timeout for waiting until spi transfer completed.
default: (CONFIG_SYS_HZ/100) /* 10 ms */
If defined, a function that provides delays in the FPGA
configuration driver.
- CONFIG_SYS_FPGA_CHECK_ERROR
+ CFG_SYS_FPGA_CHECK_ERROR
Check for configuration errors during FPGA bitfile
loading. For example, abort during Virtex II
or define CFG_ENV_FLAGS_LIST_STATIC.
- Protected RAM:
- CONFIG_PRAM
+ CFG_PRAM
Define this variable to enable the reservation of
"protected RAM", i. e. RAM which is not overwritten
- by U-Boot. Define CONFIG_PRAM to hold the number of
+ by U-Boot. Define CFG_PRAM to hold the number of
kB you want to reserve for pRAM. You can overwrite
this default value by defining an environment
variable "pram" to the number of kB you want to
- CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
undefine this when you're short of memory.
-- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
+- CFG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
width of the commands listed in the 'help' command output.
- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
- CONFIG_SYS_MC_RSV_MEM_ALIGN
Define alignment of reserved memory MC requires
-Reproducible builds
--------------------
-
-In order to achieve reproducible builds, timestamps used in the U-Boot build
-process have to be set to a fixed value.
-
-This is done using the SOURCE_DATE_EPOCH environment variable.
-SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration
-option for U-Boot or an environment variable in U-Boot.
-
-SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC.
Building the Software:
======================
base - print or set address offset
printenv- print environment variables
pwm - control pwm channels
+seama - load SEAMA NAND image
setenv - set environment variables
saveenv - save environment variables to persistent storage
protect - enable or disable FLASH write protection
[q, b, e, ?] ## Application terminated, rc = 0x0
-Minicom warning:
-================
-
-Over time, many people have reported problems when trying to use the
-"minicom" terminal emulation program for serial download. I (wd)
-consider minicom to be broken, and recommend not to use it. Under
-Unix, I recommend to use C-Kermit for general purpose use (and
-especially for kermit binary protocol download ("loadb" command), and
-use "cu" for S-Record download ("loads" command). See
-https://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
-for help with kermit.
-
-
-Nevertheless, if you absolutely want to use it try adding this
-configuration to your "File transfer protocols" section:
-
- Name Program Name U/D FullScr IO-Red. Multi
- X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
- Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
-
-
-NetBSD Notes:
-=============
-
-Starting at version 0.9.2, U-Boot supports NetBSD both as host
-(build U-Boot) and target system (boots NetBSD/mpc8xx).
-
-Building requires a cross environment; it is known to work on
-NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
-need gmake since the Makefiles are not compatible with BSD make).
-Note that the cross-powerpc package does not install include files;
-attempting to build U-Boot will fail because <machine/ansi.h> is
-missing. This file has to be installed and patched manually:
-
- # cd /usr/pkg/cross/powerpc-netbsd/include
- # mkdir powerpc
- # ln -s powerpc machine
- # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
- # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
-
-Native builds *don't* work due to incompatibilities between native
-and U-Boot include files.
-
-Booting assumes that (the first part of) the image booted is a
-stage-2 loader which in turn loads and then invokes the kernel
-proper. Loader sources will eventually appear in the NetBSD source
-tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
-meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
-
-
Implementation Internals:
=========================
new address in RAM.
-U-Boot Porting Guide:
-----------------------
-
-[Based on messages by Jerry Van Baren in the U-Boot-Users mailing
-list, October 2002]
-
-
-int main(int argc, char *argv[])
-{
- sighandler_t no_more_time;
-
- signal(SIGALRM, no_more_time);
- alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
-
- if (available_money > available_manpower) {
- Pay consultant to port U-Boot;
- return 0;
- }
-
- Download latest U-Boot source;
-
- Subscribe to u-boot mailing list;
-
- if (clueless)
- email("Hi, I am new to U-Boot, how do I get started?");
-
- while (learning) {
- Read the README file in the top level directory;
- Read https://www.denx.de/wiki/bin/view/DULG/Manual;
- Read applicable doc/README.*;
- Read the source, Luke;
- /* find . -name "*.[chS]" | xargs grep -i <keyword> */
- }
-
- if (available_money > toLocalCurrency ($2500))
- Buy a BDI3000;
- else
- Add a lot of aggravation and time;
-
- if (a similar board exists) { /* hopefully... */
- cp -a board/<similar> board/<myboard>
- cp include/configs/<similar>.h include/configs/<myboard>.h
- } else {
- Create your own board support subdirectory;
- Create your own board include/configs/<myboard>.h file;
- }
- Edit new board/<myboard> files
- Edit new include/configs/<myboard>.h
-
- while (!accepted) {
- while (!running) {
- do {
- Add / modify source code;
- } until (compiles);
- Debug;
- if (clueless)
- email("Hi, I am having problems...");
- }
- Send patch file to the U-Boot email list;
- if (reasonable critiques)
- Incorporate improvements from email list code review;
- else
- Defend code as written;
- }
-
- return 0;
-}
-
-void no_more_time (int sig)
-{
- hire_a_guru();
-}
-
-
-Coding Standards:
------------------
-
-All contributions to U-Boot should conform to the Linux kernel
-coding style; see the kernel coding style guide at
-https://www.kernel.org/doc/html/latest/process/coding-style.html, and the
-script "scripts/Lindent" in your Linux kernel source directory.
-
-Source files originating from a different project (for example the
-MTD subsystem) are generally exempt from these guidelines and are not
-reformatted to ease subsequent migration to newer versions of those
-sources.
-
-Please note that U-Boot is implemented in C (and to some small parts in
-Assembler); no C++ is used, so please do not use C++ style comments (//)
-in your code.
-
-Please also stick to the following formatting rules:
-- remove any trailing white space
-- use TAB characters for indentation and vertical alignment, not spaces
-- make sure NOT to use DOS '\r\n' line feeds
-- do not add more than 2 consecutive empty lines to source files
-- do not add trailing empty lines to source files
-
-Submissions which do not conform to the standards may be returned
-with a request to reformat the changes.
-
-
-Submitting Patches:
--------------------
-
-Since the number of patches for U-Boot is growing, we need to
-establish some rules. Submissions which do not conform to these rules
-may be rejected, even when they contain important and valuable stuff.
-
-Please see https://www.denx.de/wiki/U-Boot/Patches for details.
-
-Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
-see https://lists.denx.de/listinfo/u-boot
-
-When you send a patch, please include the following information with
-it:
-
-* For bug fixes: a description of the bug and how your patch fixes
- this bug. Please try to include a way of demonstrating that the
- patch actually fixes something.
-
-* For new features: a description of the feature and your
- implementation.
-
-* For major contributions, add a MAINTAINERS file with your
- information and associated file and directory references.
-
-* When you add support for a new board, don't forget to add a
- maintainer e-mail address to the boards.cfg file, too.
-
-* If your patch adds new configuration options, don't forget to
- document these in the README file.
-
-* The patch itself. If you are using git (which is *strongly*
- recommended) you can easily generate the patch using the
- "git format-patch". If you then use "git send-email" to send it to
- the U-Boot mailing list, you will avoid most of the common problems
- with some other mail clients.
-
- If you cannot use git, use "diff -purN OLD NEW". If your version of
- diff does not support these options, then get the latest version of
- GNU diff.
-
- The current directory when running this command shall be the parent
- directory of the U-Boot source tree (i. e. please make sure that
- your patch includes sufficient directory information for the
- affected files).
-
- We prefer patches as plain text. MIME attachments are discouraged,
- and compressed attachments must not be used.
-
-* If one logical set of modifications affects or creates several
- files, all these changes shall be submitted in a SINGLE patch file.
-
-* Changesets that contain different, unrelated modifications shall be
- submitted as SEPARATE patches, one patch per changeset.
-
-
-Notes:
-
-* Before sending the patch, run the buildman script on your patched
- source tree and make sure that no errors or warnings are reported
- for any of the boards.
-
-* Keep your modifications to the necessary minimum: A patch
- containing several unrelated changes or arbitrary reformats will be
- returned with a request to re-formatting / split it.
-
-* If you modify existing code, make sure that your new code does not
- add to the memory footprint of the code ;-) Small is beautiful!
- When adding new features, these should compile conditionally only
- (using #ifdef), and the resulting code with the new feature
- disabled must not need more memory than the old code without your
- modification.
+Contributing
+============
-* Remember that there is a size limit of 100 kB per message on the
- u-boot mailing list. Bigger patches will be moderated. If they are
- reasonable and not too big, they will be acknowledged. But patches
- bigger than the size limit should be avoided.
+The U-Boot projects depends on contributions from the user community.
+If you want to participate, please, have a look at the 'General'
+section of https://u-boot.readthedocs.io/en/latest/develop/index.html
+where we describe coding standards and the patch submission process.
projects / platform / kernel / u-boot.git / blobdiff