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Patrick Rudolph 29ed4f56b5 arch/x86/gdt: Work around assembler bug
The GDT loading did work fine on x86_64 a few months ago, but today it
only works in QEMU, but not on real hardware or KVM-enabled QEMU. This
might be related to toolchain changes.

Use 64bit GDT loading on x86_64 and force the assembler to generate a
64bit address load on the GDT. This will make sure no 32bit (signed)
displacement op is being generated, which points to the wrong address
in longmode.

Verified using readelf and made sure no R_X86_64_32S relocation symbol
is emitted. Disassembled the romstage ELF and made sure the GDT address
is 64bit in size.

Tested on QEMU and KVM-enabled QEMU: Doesn't crash any more on KVM.

Signed-off-by: Patrick Rudolph <siro@das-labor.org>
Change-Id: Ia824f90d9611e6e8db09bd62a05e6f990581f09a
Reviewed-on: https://review.coreboot.org/c/coreboot/+/43136
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
2020-08-21 16:01:42 +00:00
3rdparty 3rdparty/vboot: Update to latest master 2020-08-20 21:06:27 +00:00
Documentation mb/emulation/qemu-q35,qemu-i440fx: Add x86_64 support 2020-08-19 10:50:49 +00:00
LICENSES drivers: Use SPDX identifiers 2020-05-25 22:19:21 +00:00
configs configs: Build test experimental x86_64 code 2020-08-19 10:54:45 +00:00
payloads arch/arm: Enable FIT payloads 2020-08-19 07:16:59 +00:00
src arch/x86/gdt: Work around assembler bug 2020-08-21 16:01:42 +00:00
tests tests: Improve test_skip_atoi() in /lib/string-test test case 2020-07-12 19:38:39 +00:00
util util/abuild: Avoid another git submodule invocation 2020-08-19 20:21:33 +00:00
.checkpatch.conf
.clang-format
.editorconfig
.gitignore
.gitmodules Add qc_blobs repository 2020-06-30 08:57:03 +00:00
.gitreview
AUTHORS AUTHORS, util/: Drop individual copyright notices 2020-05-09 21:21:32 +00:00
COPYING
MAINTAINERS cpu/ti/am335x: Move from cpu to soc in tree 2020-08-19 07:17:37 +00:00
Makefile build system: Rely on xcompile for HOSTCC and HOSTCXX 2020-07-08 08:53:46 +00:00
Makefile.inc Makefile.inc: Remove redundant warning flag 2020-08-17 07:08:31 +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.