bed82b0c40
Presently, coreboot supports two instances of sending EOP cmd to the Intel CSE. 1. Sending EOP cmd to CSE during `.final` operation from cse pci driver. 2. Starting with Alder Lake, the recommendation was to send EOP to CSE earlier than CSE `.final` operation. Since then it's referred to as `Sending EOP Early`. This method helped to save the CSE EOP response time significantly. During Meteor Lake platform, CSE EOP response time has become non-deterministic and we have figured that sending EOP command later than CSE .final operation is actually helping to optimize the boot time significantly (around ~150ms savings compared to sending from `.final` ops and ~5sec compared to sending CSE early). Hence, this patch intended to create yet another kconfig for sending CSE late (specifically after `.final` operation). The idea for this newer config is to use the boot state machine for sending CSE EOP cmd. The patch train in this series would add the specific changes to allow sending EOP late and perform other essential operations required prior booting to OS as coreboot decided to skip calling into FSP Notify phase. Starting with Jasper Lake, coreboot sends EOP before loading payload hence, this config is applicable for those platforms. The current plan is that Intel Jasper Lake, Tiger Lake and Meteor Lake platform will select this newer config from SoC code. BUG=b:260041679 TEST=Able to send EOP command successfully for Google/Taeko. Signed-off-by: Subrata Banik <subratabanik@google.com> Change-Id: Iea512cd5b79d61dd5d5a962079baf525027c831f Reviewed-on: https://review.coreboot.org/c/coreboot/+/69976 Reviewed-by: Kapil Porwal <kapilporwal@google.com> Reviewed-by: Lean Sheng Tan <sheng.tan@9elements.com> Tested-by: build bot (Jenkins) <no-reply@coreboot.org> |
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| LICENSES | ||
| configs | ||
| payloads | ||
| spd | ||
| src | ||
| tests | ||
| util | ||
| .checkpatch.conf | ||
| .clang-format | ||
| .editorconfig | ||
| .gitignore | ||
| .gitmodules | ||
| .gitreview | ||
| .mailmap | ||
| 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:
- 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.