Daniel Vetter authored Mar 02, 2010 and Carl Worth committed Mar 04, 2010

Cache coherency is now fully under the control of gem.

For lack of hw documentation, I had to find out the correct cache
placements by trial and error:

Backward and forward surfaces: I915_GEM_DOMAIN_RENDER
Correlation data:              I915_GEM_DOMAIN_SAMPLER

Changing any of them leads to visual corruptions, so I think these
are the correct ones.

Reviewed-by: Carl Worth <cworth@cworth.org>