[coreboot] option roms in SeaBIOS and Coreboot

Kevin O'Connor kevin at koconnor.net
Wed Nov 26 06:40:44 CET 2008

On Tue, Nov 25, 2008 at 11:38:29AM +0100, Rudolf Marek wrote:
>> Note that your patch doesn't seem to disable the mapping after the
>> copy.  This is definitely necessary.  Maybe add something like:
>>     pci_config_writel(bdf, PCI_ROM_ADDRESS, orig & ~PCI_ROM_ADDRESS_ENABLE);
> Why we need it to disable? Just curious. Coreboot has assigned the 
> address to it so we are sure we won't be hit by something else.

PCI cards aren't required to support option rom BAR accesses at the
same time as regular BAR accesses.  So, one can't leave the option rom
mapped while accessing the other mapped areas.

> OK the behavior did not change anyway.
> I can try to test with mine PCIe SATA card. Do you think it will 
> correctly patch the BIOS so I will be at the end able to boot from it?

Well, it should work.  :-)


More information about the coreboot mailing list