[coreboot] SimNOW VGA int 1a
marc.jones at amd.com
Thu Oct 16 18:31:56 CEST 2008
Myles Watson wrote:
> On Thu, Oct 16, 2008 at 9:49 AM, ron minnich <rminnich at gmail.com
> <mailto:rminnich at gmail.com>> wrote:
> On Thu, Oct 16, 2008 at 8:48 AM, Myles Watson <mylesgw at gmail.com
> <mailto:mylesgw at gmail.com>> wrote:
> >> >> > Check PCI: 1022:2067
> >> >> > found
> >> >> > 0xb102: return 0x120
> >> the wrong # here?
> > Yes. It should be device # 4 as far as I can tell. In the
> debugger when I
> > do a config read to bus 1 dev 4 function 0 I get the right data
> back. When
> > I do a read to bus 1 dev 2 function 0 I get an error that no device
> > responded.
> > Like I said, I don't know why the reads succeed.
> so you need some debug prints in the PCIBIOS support code.
> Check PCI: 1022:2067
> PCI: 01:04.0 found
> bus->secondary = 0x1 dev->path.pci.devfn = 0x20
> 0xb102: return 0x120
> Now I'm confused. I guess 0x120 was correct (the slot is the upper 5
> bits of the byte), so I'm still looking. Now it makes sense why the
> reads succeed, but the config write failure is puzzling. It's trying
> to write 0xffffffff to the BAR, but that changes the memory map, so
> after that write there's garbage everywhere. I still haven't found
> the config register that gets changed, but it's not in the VGA card's
Which BAR? What is the contents of 0xcf8? Not sure why, but writing
0xFFFFFFFF to a BAR is to get the size. It shoudl disable the device
before it does that but sometimes they are sloppy and don't.
Senior Firmware Engineer
(970) 226-9684 Office
mailto:Marc.Jones at amd.com
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