PowerMac G4 graphics issue

[Alexey Dokuchaev]

On Sat, Nov 08, 2008 at 02:06:21PM -0800, Chris "Bigguy" wrote:
> Just today I've FINALLY gotten Debian linux to work properly on my Power
> Mac Digital Audio with Nvidia graphics card.  Getting the graphics right
> took many weeks to figure out, but I can now report the fix is easy.
> 
> Edit the file /etc/X11/xorg.conf and change the value of "UseFBDev" from
> "true" to "false".  This one change takes the system from not-working-at-
> all to OMG this is great!
> 
> By the way, I have reason to believe that this fix is not required if an
> ATI graphics card is installed.

Looks like it is required for ATI (AMD) cards as well; at least on my Mac
mini G4 with Radeon 9200 (RV200) it allowed the correct driver to be used
(ati, not fbdev).  However, I'm still not quite there yet, seeing these
infamous lines in the /var/log/Xorg.0.log:

  [347050.379] (WW) xf86EnableIO 7
  [347050.379] (II) xf86EnableIO: ffffffff
  [347050.379] (WW) Can't map IO space!
  [347050.379] (EE) No devices detected.

Advice about setting sysctl hw.ofwfb.relax_mmap=1 is not helpful since I
do not have this sysctl node.  Any clues?

./danfe