ç­å¤: K8 northbridge f1 behaviour.

Eric W. Biederman ebiederman at lnxi.com
Thu Jan 8 23:52:01 CET 2004

Li-Ta Lo <ollie at lanl.gov> writes:

> On Thu, 2004-01-08 at 15:43, YhLu wrote:
> > Ron,
> > 
> > You need to set the REG in some special position. Because ht_scanbus, may
> > reset some regs according to it's scan result.

I know the existing code when it was back in the freebios codebase and PCI
only handled this correctly, so it should be just a matter of a little bit
of debugging to get this to happen automatically if it does not already.

> > I think the best to use VGA is
> > 1. LinuxBIOS init critical regs to make sure VGA can be used in Linux
> > kernel.
> > 2. Linux Kernel does the special work to make use some acceleration function
> > works.
> > 3. Let X Server no changes.
> > 
> YhLu,
> We found that under normal bios, the AMD8151 is not present. Is there 
> any bits to hide it ?

Hmm.  This may because of how things are laid out.  
I wonder if there are driver issues when you put the 8151 on something
besides bus 0.

> We have tried everything to forward VGAIO behind 8111 and 8151
> bridges but fail. Do you know anything about it ?

That is very weird.  Besides the card not working what test
are you using to be certain you have failed?  Are you failing
to read/write an I/O register.

It occurs to me LinuxBIOS might be different enough in pci layout to
confuse the option ROM on your card.

Plus I think there are some special bits of AGP initialization that
we might not be doing.


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