Hello,

here's something to play with - it should enable you to use XFree86 
with the onboard ATI Rage found on Sun Ultra 10 and others.

You can find the necessary stuff here:
http://macallan.homeunix.org:6704/stuff/BSD/sparc64/

The kernel contains support for the Ultra 10 hardware plus USB, esiop 
and a display driver stolen from macppc (ofb) so we have wscons, it 
should work on the Ultra 5 and probably others too but I have no way to 
verify this.
I had to do some voodoo to get XFree to work, mainly to allow mapping 
of PCI memory through ofb, so XFree can keep pretending that the BAR 
registers contain real, physical addresses, ofb simply translates them 
using bus_space_mmap(). Should be restricted to what belongs to the 
graphics controller though.
CAUTION: the kernel uses ttyE0 as console device and 'sun' terminal 
emulation, you'll have to change /etc/ttys or login through ssh or 
telnet. This doesn't have an effect when booting single user though.

X itself didn't need any real changes, I only had to force it to build 
the XFree86 Xserver and friends. The tarball contains the whole thing, 
compiled straight from xsrc for a 2.0 userland. It didn't build things 
like xf86config for some reason - I didn't get around to find out why 
yet, there are more important things to do.

The XF86Config I supplied is extremely basic, it allows the Xserver to 
run, but that's it. The Sun keyboard doesn't work correctly, there are 
two possible reasons:
- the driver doesn't play well with wscons, there's a bug somewhere, I 
just compensated it with an ugly hack which should go away. It loses 
events even on the console. USB keyboards just work ( ironically I use 
a Sun Type 6 USB )
- the keyboard type isn't specified - maybe XFree can be persuaded to 
talk to it by hacking XF86Config, I didn't (yet) bother to do so
The Sun mouse works just as it should, I didn't test USB mice but I 
don't see a reason why they shouldn't work.

good luck
Michael