f5b30eda1f
This change updates the translated region device (xlate_region_dev) to support multiple translation windows from the 1st address space to 2nd address space. The address spaces described by the translation windows can be non-contiguous in both spaces. This is required so that newer x86 platforms can describe memory mapping of SPI flash into multiple decode windows in order to support greater than 16MiB of memory mapped space. Since the windows can be non-contiguous, it introduces new restrictions on the region device ops - any operation performed on the translated region device is limited to only 1 window at a time. This restriction is primarily because of the mmap operation. The caller expects that the memory mapped space is contiguous, however, that is not true anymore. Thus, even though the other operations (readat, writeat, eraseat) can be updated to translate into multiple operations one for each access device, all operations across multiple windows are prohibited for the sake of consistency. It is the responsibility of the platform to ensure that any section that is operated on using the translated region device does not span multiple windows in the fmap description. One additional difference in behavior is xlate_region_device does not perform any action in munmap call. This is because it does not keep track of the access device that was used to service the mmap request. Currently, xlate_region_device is used only by memory mapped boot media on the backend. So, not doing unmap is fine. If this needs to be changed in the future, xlate_region_device will have to accept a pre-allocated space from the caller to keep track of all mapping requests. BUG=b:171534504 Change-Id: Id5b21ffca2c8d6a9dfc37a878429aed4a8301651 Signed-off-by: Furquan Shaikh <furquan@google.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/47658 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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| Documentation | ||
| LICENSES | ||
| configs | ||
| payloads | ||
| src | ||
| tests | ||
| util | ||
| .checkpatch.conf | ||
| .clang-format | ||
| .editorconfig | ||
| .gitignore | ||
| .gitmodules | ||
| .gitreview | ||
| AUTHORS | ||
| COPYING | ||
| MAINTAINERS | ||
| Makefile | ||
| Makefile.inc | ||
| README.md | ||
| gnat.adc | ||
| toolchain.inc | ||
README.md
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_TOOLCHAINKconfig 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 menuconfigandmake 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.