Re: [coreboot] Back to original BIOS

[Peter Stuge]

Michal Widlok wrote:
> Peter: Is that really the case with old T400?

I don't have experience with T400, but on older models still it was
very much the case that the BIOS image had some information in it,
which was compared with the actual hardware at runtime, and in case
of mismatch the platform did not boot.

I always assumed that it's a handshake between BIOS and the AT24RF
EEPROM which includes some extra special functionality. On platforms
with ME it wouldn't surprise me too much if all that moved into the
ME, or even disappeared completely, but I *have* had the problem in
the past.

I didn't research exactly what information it is, or exactly what the
handshake is, I always worked around the problem by flashing the
backup.

//Peter

Back to original BIOS

[ron minnich]

Given the way vendors swap parts around, it would not be surprising to find
settings such as GPIOs that control mainboard resources and DRAM timing in
flash. There's lots of ways to save some money nowadays (e.g. remove SPD)
and vendors do what they can to save it all.

ron