[ubuntu-x] Debugging KMS (and thoughts thereof)

[Bryce Harrington]

On Wed, Mar 17, 2010 at 02:12:04AM +0000, Scott James Remnant wrote:
> On Tue, 2010-03-16 at 18:44 -0700, Bryce Harrington wrote:
> 
> > As we move into the new world of KMS, I'm noticing that a lot of our
> > established procedures and tools for debugging modesetting problems no
> > longer work.
> > 
> One thing I did notice from talking with upstream nouveau today and
> debugging the Latitude D620 - our kernels don't have mmiotrace support
> compiled in.
> 
> I'm not sure why, perhaps kernel team could answer that?
> 
> It looks like a tracer like any other, and has to be enabled through
> sysfs before it actually traces - surely this would be a good thing to
> have?

Yeah RAOF and I discussed adding mmiotrace support in our debugging
tools.  He didn't think it would buy us much.  But I'll let him
explain his findings...
 
> That then turns all nouveau issues into "fire up nvidia-glx under
> mmiotrace", "send upstream"

Ha if only it were so simple.  All our bugs would belong to them.

Bryce