[igt-dev] [PATCH i-g-t 2/2] i915/treewide: Replace gem_mmap__gtt() by gem_mmap__device_coherent()

[Dixit, Ashutosh]

On Wed, 15 Jan 2020 08:27:40 -0800, Imre Deak wrote:
>
> Hi,
>
> On Fri, Jan 10, 2020 at 09:36:53PM -0800, Ashutosh Dixit wrote:
> > As another step towards supporting GPU's without mappable aperture,
> > globally replace gem_mmap__gtt() by gem_mmap__device_coherent(). This
> > will not affect GPU's with a mappable aperture but will fix tests on
> > GPU's without a mappable aperture through the use of WC mapping,
> > unless those tests test actual features available via the aperture.
>
> igt_draw_rect() depends on detiling via the aperture. I'd suggest
> converting first only the places that don't depend on this and follow-up
> with the rest once we have a way to do the detiling in another way.

Patch 1/2 was supposed to take care of this so that at least platforms with
mappable aperture don't break. Platforms without mappable aperture anyway
need to figure out a different way, but I agree, you are probably saying
just don't touch them in this patch.

In any case we are not moving forward with this approach at this point
because of Chris' comments.