In a rare placement edge case when adding a file with alignment requirements, cbfstool may need to generate a CBFS header that's slightly larger than it needs to be. The way we do this is by just increasing the data offset field in the CBFS header until the data falls to the desired value. This approach works but it may confuse parsing code in the presence of CBFS attributes. Normally, the whole area between the attribute offset and the data offset is filled with valid attributes written back to back, but when this header expansion occurs the attributes are followed by some garbage data (usually 0xff). Parsers are resilient against this but may show unexpected error messages. This patch solves the problem by moving the attribute offset forwards together with the data offset, so that the total area used for attributes doesn't change. Instead, the filename field becomes the expanded area, which is a closer match to how this worked when it was originally implemented (before attributes existed) and is less confusing for parsers since filenames are zero-terminated anyway. Signed-off-by: Julius Werner <jwerner@chromium.org> Change-Id: I3dd503dd5c9e6c4be437f694a7f8993a57168c2b Reviewed-on: https://review.coreboot.org/c/coreboot/+/47824 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Angel Pons <th3fanbus@gmail.com> Reviewed-by: Aaron Durbin <adurbin@chromium.org> |
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3rdparty | ||
configs | ||
Documentation | ||
LICENSES | ||
payloads | ||
src | ||
tests | ||
util | ||
.checkpatch.conf | ||
.clang-format | ||
.editorconfig | ||
.gitignore | ||
.gitmodules | ||
.gitreview | ||
AUTHORS | ||
COPYING | ||
gnat.adc | ||
MAINTAINERS | ||
Makefile | ||
Makefile.inc | ||
README.md | ||
toolchain.inc |
coreboot README
coreboot is a Free Software project aimed at replacing the proprietary BIOS (firmware) found in most computers. coreboot performs a little bit of hardware initialization and then executes additional boot logic, called a payload.
With the separation of hardware initialization and later boot logic, coreboot can scale from specialized applications that run directly firmware, run operating systems in flash, load custom bootloaders, or implement firmware standards, like PC BIOS services or UEFI. This allows for systems to only include the features necessary in the target application, reducing the amount of code and flash space required.
coreboot was formerly known as LinuxBIOS.
Payloads
After the basic initialization of the hardware has been performed, any desired "payload" can be started by coreboot.
See https://www.coreboot.org/Payloads for a list of supported payloads.
Supported Hardware
coreboot supports a wide range of chipsets, devices, and mainboards.
For details please consult:
Build Requirements
- make
- gcc / g++
Because Linux distribution compilers tend to use lots of patches. coreboot
does lots of "unusual" things in its build system, some of which break due
to those patches, sometimes by gcc aborting, sometimes - and that's worse -
by generating broken object code.
Two options: use our toolchain (eg. make crosstools-i386) or enable the
ANY_TOOLCHAIN
Kconfig option if you're feeling lucky (no support in this case). - iasl (for targets with ACPI support)
- pkg-config
- libssl-dev (openssl)
Optional:
- doxygen (for generating/viewing documentation)
- gdb (for better debugging facilities on some targets)
- ncurses (for
make menuconfig
andmake nconfig
) - flex and bison (for regenerating parsers)
Building coreboot
Please consult https://www.coreboot.org/Build_HOWTO for details.
Testing coreboot Without Modifying Your Hardware
If you want to test coreboot without any risks before you really decide to use it on your hardware, you can use the QEMU system emulator to run coreboot virtually in QEMU.
Please see https://www.coreboot.org/QEMU for details.
Website and Mailing List
Further details on the project, a FAQ, many HOWTOs, news, development guidelines and more can be found on the coreboot website:
You can contact us directly on the coreboot mailing list:
https://www.coreboot.org/Mailinglist
Copyright and License
The copyright on coreboot is owned by quite a large number of individual developers and companies. Please check the individual source files for details.
coreboot is licensed under the terms of the GNU General Public License (GPL). Some files are licensed under the "GPL (version 2, or any later version)", and some files are licensed under the "GPL, version 2". For some parts, which were derived from other projects, other (GPL-compatible) licenses may apply. Please check the individual source files for details.
This makes the resulting coreboot images licensed under the GPL, version 2.