xf 4.0.1 with rage II/rage pro -- multi-headed display!

[Geert Uytterhoeven]

On Tue, 26 Sep 2000, Michael Schmitz wrote:
> > > > Are there known X-related problems using BootX?
> > >
> > > You were looking at it, from what I guess. Apple's drivers set up
> > > overlapping areas for MMIO and VRAM, and X fixes this by disabling one of
> > > these. Unfortunatly, the kernel doesn't notice.
> >
> > Fortunately these PCI assignment bugs should be circumvented by the new PCI
> > code we're working on.
>
> ... in 2.4.x, I believe. Problem is, most people aren't crazy enough to
> use 2.4.0 (-test8 in particular).
>
> All you can do in 2.2 is the 'pick and pray' approach: pick an alternate
> address for MMIO bases on some heuristics or wild guesses, and pray you
> don't trample on other card's resources. Works for me, but I warn anyone
> to be careful with that method.
>
> I've posted such a patch to debian-powerpc when one user there had this
> problem. That was before I learned booting with yaboot avoids the problem.
> If the resource conflict also happens on oldworld machines, I'd still
> prefer some suggestions to foolproof the patch (as in: how can I figure
> out if a region has been allocated by another card? What bits from the
> config registers should I look at?).

You should walk all PCI devices and construct your own resource tree from
pci_dev->base_address[i]. After that you know the conflicts and unassigned
addresses and can look for free space. Unfortunately this is probably nearly
as much work as backporting the 2.4.x PCI resource code (which is tested,
unlike new code you would invent).

Gr{oetje,eeting}s,

						Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
							    -- Linus Torvalds


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