Resource Allocation for Option Rom

ron minnich rminnich at
Thu May 27 16:00:27 CEST 2004

On Thu, 27 May 2004, Stefan Reinauer wrote:

> * Li-Ta Lo <ollie at> [040527 22:49]:
> > > Also, the graphics card option roms are usually hardcoded to 0xc0000
> > 
> > Do you mean the expansion rom BAR is hard coded to 0xc0000 ?
> > The how does the bios copy the bios in ROM at 0xc0000 to memory
> > in DRAM at 0xc0000 as stated in PCI spec ?
> I know some intel chipsets did this by forwarding reads from 0xc0000 to rom
> and writes to 0xc0000 to ram, then reading and rewriting the whole area
> to the same address. I'd assume that this is still handled similar but
> on AMD64 rather using the MEM maps?

again, you do not need to map option roms at 0c0000 in the emulator!

Map it anywhere, tell the emulator the location, and the emulator can 
satisfy memory "fetches" for c0000 by fetching from that location. 

Emulators are good.


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