Coreboot

Building in nix-shell

To build your own coreboot bios:

git clone https://review.coreboot.org/coreboot.git --depth 1
cd coreboot
du -sh . # 200 MByte
git submodule update --init --checkout --depth 1
du -sh . # 700 MByte

nix-shell -p ncurses bison flex clang gnat10 gnatboot zlib acpica-tools pkgconfig qemu
NIX_LDFLAGS="$NIX_LDFLAGS -lncurses" make menuconfig
make crossgcc CPUS=$(nproc)
make

qemu-system-x86_64 -bios build/coreboot.rom -serial stdio

• gnat10 provides gnat
• gnatboot provides gnat1

Compiler version

gcc (provided by clang) and gnat (the GNU Ada compiler) must have the same version

gcc --version
gnat --version

For example, both have version 10.3.0

Building as derivation

coreboot is pretty picky about the toolchain it is built with and thus using the toolchain it comes with is the easiest path to success. There are commented Nix expressions that build coreboot here.

See also

• https://www.coreboot.org/Build_HOWTO
• https://www.coreboot.org/Lesson1
• flashing the new bios image
  • https://doc.coreboot.org/flash_tutorial/
  • https://libreboot.org/docs/install/spi.html