SeaBIOS

From coreboot

SeaBIOS (previously known as LegacyBIOS) is an open-source legacy BIOS implementation, which can also be used as coreboot payload.

Building

SeaBIOS

You can download the latest version of SeaBIOS through a git repository:

$ git clone git://git.linuxtogo.org/home/kevin/seabios.git seabios
$ cd seabios

Alternatively, the released versions of SeaBIOS can be found at http://linuxtogo.org/~kevin/legacybios/.

Edit src/config.h and set the following values:

#define CONFIG_COREBOOT 1
#define CONFIG_DEBUG_SERIAL 1
#define CONFIG_PCIBIOS 0

Then:

$ make AVOIDCOMBINE=1

The final SeaBIOS payload file is out/bios.bin.elf, which can be used with coreboot v2 or v3.

coreboot

Finally, you have to build coreboot (v3 in this example) with SeaBIOS as payload:

$ cd ..
$ svn co svn://coreboot.org/repository/coreboot-v3
$ cp seabios/out/bios.bin.elf coreboot-v3/payload.elf
$ cd coreboot-v3
$ make menuconfig

Now enter the Payload menu and select Payload type and then An ELF executable payload file. Now exit the menu, save your settings, and build coreboot:

$ make

The file build/coreboot.rom (or build/bios.bin) is your final coreboot v3 image, which also contains the SeaBIOS payload.

Running SeaBIOS in QEMU

For running coreboot+SeaBIOS in QEMU, you need a patched version of vgabios-cirrus.bin in your build directory first:

$ cd build
$ wget http://www.coreboot.org/images/0/0d/Vgabios-cirrus.zip
$ unzip Vgabios-cirrus.zip
$ cd ..

You can now run LegacyBIOS in QEMU:

$ qemu -L build -hda /dev/zero -serial stdio

Ready-made LegacyBIOS QEMU image

TODO

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