[coreboot] [RFC] Here we go... the SLOF biosemu for coreboot-v3

[Myles Watson]

> From: Pattrick Hueper [mailto:phueper at hueper.net]
> Hi,
> 
> i havent had time to look into seabios.
> What i read/heard of seabios, it seems, that it is pretty much tied
> with the x86 architecture, whereas the SLOF biosemu is designed to be
> architecture
> independent, and for me it has proven to be so by being ported from
> OF/PPC to coreboot/x86 with reasonable effort.
> 
> Being architecture independent, i think the biosemu has to keep its
> own set of Interrupt Vectors and virtual 1MB memory area (which is, by
> the way currently hard coded to 16MB of real memory i think...)
> That makes it possible to reenter biosemu e.g. for VBE calls (which we
> did in SLOF, the code is initializing the card by running the Option
> ROM first and later on reenters biosemu to switch to
> framebuffer mode). Of course in a x86 coreboot this might need to be
> redesigned... then again for a x86 coreboot, seabios or vm86 might be
> the better / faster choices anyway.
> 
> I started working on porting v3 to qemu-ppc... once i have some serial
> output, i will post patches. And i hope to hack qemu-ppc to use the
> same cirrus
> vga card and exprom and be able to initialize it in qemu-ppc though it
> remains to be seen, wether that will work or wether it is already
> there...

I think this makes your case much stronger.  I didn't realize you were
porting v3 to PPC.  You're right that seabios is x86-specific.

Myles