6b6e9b503d
cbfstool overloads baseaddress to represent multiple things: 1. Address in SPI flash space 2. Address in host space (for x86 platforms) 3. Offset from end of region (accepted as negative number) This was done so that the different functions that use these addresses/offsets don't need to be aware of what the value represents and can use the helper functions convert_to_from* to get the required values. Thus, even if the user provides a negative value to represent offset from end of region, it was stored as an unsigned integer. There are special checks in convert_to_from_top_aligned which guesses if the value provided is really an offset from the end of region and converts it to an offset from start of region. This has worked okay until now for x86 platforms because there is a single fixed decode window mapping the SPI flash to host address space. However, going forward new platforms might need to support more decode windows that are not contiguous in the host space. Thus, it is important to distinguish between offsets from end of region and addresses in host/SPI flash space and treat them separately. As a first step towards supporting this requirement for multiple decode windows on new platforms, this change handles the negative offset provided as input in dispatch_command before the requested cbfs operation is performed. This change adds baseaddress_input, headeroffset_input and cbfsoffset_input to struct param and converts them to offsets from start of region before storing into baseaddress, headeroffset and cbfsoffset if the inputs are negative. In follow up changes, cbfstool will be extended to add support for multiple decode windows. BUG=b:171534504 TEST=Verified using abuild with timeless option for all coreboot boards that there is no change in the resultant coreboot.rom file. Change-Id: Ib74a7e6ed9e88fbc5489640d73bedac14872953f Signed-off-by: Furquan Shaikh <furquan@google.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/47829 Reviewed-by: Duncan Laurie <dlaurie@chromium.org> Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org> Tested-by: build bot (Jenkins) <no-reply@coreboot.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.