25d01be47d
Enabling Bus Master isn't required by the hardware, so we shouldn't
need to enable it at all. However, some payloads do not set this bit
before attempting DMA transfers, which results in functionality
failure. For example: in this case, unable to see the developer screen
in Depthcharge.
In the prior IA SoC platform, FSP/GFX PEIM does the BM enabling for
the IGD BAR resources but starting with the MTL platform, it fails
to do so resulting into inability to see the Pre-OS display.
BUG=b:243919230 ([Rex] Unable to see Pre-OS display although GFX
PEIM Display Init is successful during AP boot)
TEST=Able to see the developer screen with eDP/HDMI while booting
the Google/Rex.
Also, this change doesn't impact the previous platforms
(ADL, TGL, CML etc.) where the BM is default enabled.
Signed-off-by: Subrata Banik <subratabanik@google.com>
Change-Id: I9ad9eee8379b7ea1e50224e3fabb347e5f14c25b
Reviewed-on: https://review.coreboot.org/c/coreboot/+/67273
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Tarun Tuli <taruntuli@google.com>
Reviewed-by: Werner Zeh <werner.zeh@siemens.com>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Wonkyu Kim <wonkyu.kim@intel.com>
Reviewed-by: Jamie Ryu <jamie.m.ryu@intel.com>
Reviewed-by: Kapil Porwal <kapilporwal@google.com>
|
||
|---|---|---|
| 3rdparty | ||
| configs | ||
| Documentation | ||
| LICENSES | ||
| payloads | ||
| spd | ||
| src | ||
| tests | ||
| util | ||
| .checkpatch.conf | ||
| .clang-format | ||
| .editorconfig | ||
| .gitignore | ||
| .gitmodules | ||
| .gitreview | ||
| .mailmap | ||
| 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_TOOLCHAINKconfig option if you're feeling lucky (no support in this case). - iasl (for targets with ACPI support)
- pkg-config
- libssl-dev (openssl)
Optional:
- 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.