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Re: call for testers - switching ofppc to xorg X11



matthew green wrote:

> frank, could you explain what this patch is doing?  or more exactly,
> why?  what's with the AGP enablement?

I'm not sure about the technical details, but I guess that you have to
switch the Marvell controller into AGP-mode to be able to access AGP-cards
on the PCI bus. The Pegasos2 has no real AGP bus, it is somehow...
emulated?

By writing 0x08000000 to GT_GPP_Value_Set the configuration space of AGP
cards becomes visible. Writing the same value to GP_GPP_Value_Clear makes
them disappear again.

The problem in the original source was that the AGP configuration space was
only enabled during autoconfig. So every PCI bus scan after that was unable
to see AGP cards.

-- 
Frank Wille



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