Thank you for your work on Dual BIOS.
What I don't understand is how is this supposed to work.
From what you say and what I asked sales cotact staff at gigabyte (no
very useful insights) , there are two bios roms. One has the ability to check the other and run it only if it detects it's ok. If it doesn't it flashes itself to it.
So if you use one of the BIOS for coreboot it will either be rewriten by the original BIOS or it will boot, depending on which ROM boots first and which ROM you put coreboot in.
If you flash the ROM that boots first you can try coreboot, but in case it doesn't work how are you going to jump to the original BIOS ?
If you flash the other ROM then apparently the original BIOS will boot and do what it pleases, possibly overwrite coreboot, or assuming you can trick it to believe coreboot is a correct BIOS then maybe jump to it after some initialisation, but will coreboot then have a chance to work from the same state it would in case it had booted first ?
Tricking the original BIOS to believe coreboot is a correct image may be hard. In the worst case you may have to break a digital signature without the private key. This is not directly related, but gives an idea of how hard it could be
http://invisiblethingslab.com/resources/bh09usa/Attacking Intel BIOS.pdf
But assuming you can, will using coreboot after other firmware has set up things far enough to be able to test the ROM where coreboot is in, will that be a sufficient test ? I'm not saying it won't, I have no clue.
Anyway, being able to flash both chips is good at the very least in order to have more space for payloads or so.