Re: pci_fixup_video() bogosity

From: Jon Smirl
Date: Tue Mar 08 2005 - 01:02:27 EST

On Tue, 08 Mar 2005 15:38:29 +1100, Benjamin Herrenschmidt
<benh@xxxxxxxxxxxxxxxxxxx> wrote:
> Hi !
> While working on writing a VGA access arbiter for kernel & userland,
> I wondered how to properly get my "initial" state at boot. For that,
> I looked at how the new PCI ROM stuff does to find out who owns the
> memory shadow at c0000, and found it quite bogus.
> >From what I see, the code is only based on looking at what bridges
> have VGA forwarding enabled. It doesn't test the actual IO and Memory
> enable bits of the VGA cards themselves.

Let's fix it up and make it more robust. I was playing with checking
IO/mem enable and forgot to finish it.

> What if you have 2 cards under the same bridge ?

I believe the default on x86 is to pick the one in the lowest slot
number. What happens on PPC?

Jon Smirl
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