Go to file
Angel Pons 8f8cb95fe9 sec/intel/txt: Split MTRR setup ASM code into a macro
If necessary, SCLEAN needs to run in early romstage, where DRAM is not
working yet. In fact, that the DRAM isn't working is the reason to run
SCLEAN in the first place. Before running GETSEC, CAR needs to be torn
down, as MTRRs have to be reprogrammed to cache the BIOS ACM. Further,
running SCLEAN leaves the system in an undefined state, where the only
sane thing to do is reset the platform. Thus, invoking SCLEAN requires
specific assembly prologue and epilogue sections before and after MTRR
setup, and neither DRAM nor CAR may be relied upon for the MTRR setup.

In order to handle this without duplicating the MTRR setup code, place
it in a macro on a separate file. This needs to be a macro because the
call and return instructions rely on the stack being usable, and it is
not the case for SCLEAN. The MTRR code clobbers many registers, but no
other choice remains when the registers cannot be saved anywhere else.

Tested on Asrock B85M Pro4, BIOS ACM can still be launched.

Change-Id: I2f5e82f57b458ca1637790ddc1ddc14bba68ac49
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/46603
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
2020-10-22 20:06:54 +00:00
3rdparty 3rdparty/amd_blobs: update submodule pointer 2020-10-21 13:45:30 +00:00
Documentation drivers/smmstore: Implement SMMSTORE version 2 2020-10-22 12:29:47 +00:00
LICENSES drivers: Use SPDX identifiers 2020-05-25 22:19:21 +00:00
configs configs: Add TXT-enabled config for Asrock B85M Pro4 2020-10-22 19:59:30 +00:00
payloads drivers/smmstore: Implement SMMSTORE version 2 2020-10-22 12:29:47 +00:00
src sec/intel/txt: Split MTRR setup ASM code into a macro 2020-10-22 20:06:54 +00:00
tests device/dram: Add method for converting MHz to MT/s 2020-09-16 03:24:50 +00:00
util util/abuild/abuild: Do not check out submodules 2020-10-19 07:07:31 +00:00
.checkpatch.conf
.clang-format
.editorconfig
.gitignore .gitignore: Do not let git track '*.fd' 2020-10-14 09:24:25 +00:00
.gitmodules 3rdparty: Add STM as a submodule 2020-09-30 10:17:03 +00:00
.gitreview
AUTHORS AUTHORS, util/: Drop individual copyright notices 2020-05-09 21:21:32 +00:00
COPYING
MAINTAINERS MAINTAINERS: add Michael Niewöhner to mb/clevo 2020-10-15 12:24:11 +00:00
Makefile build system: Rely on xcompile for HOSTCC and HOSTCXX 2020-07-08 08:53:46 +00:00
Makefile.inc drivers/intel/usb4: Add driver for USB4 retimer device 2020-10-19 06:51:40 +00:00
README.md
gnat.adc treewide: Remove "this file is part of" lines 2020-05-11 17:11:40 +00:00
toolchain.inc Remove MAYBE_STATIC_BSS and ENV_STAGE_HAS_BSS_SECTION 2020-05-26 15:04:08 +00:00

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_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 and make 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:

https://www.coreboot.org

You can contact us directly on the coreboot mailing list:

https://www.coreboot.org/Mailinglist

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.