[Intel-gfx] [PATCH 08/16] drm/i915: remove unused restore_gtt_mappings optimization during suspend

[Jesse Barnes]

On Thu, 11 Sep 2014 14:59:35 +0300
Imre Deak <imre.deak at intel.com> wrote:

> On Thu, 2014-09-11 at 08:49 +0100, Chris Wilson wrote:
> > On Wed, Sep 10, 2014 at 06:17:01PM +0300, Imre Deak wrote:
> > > Since correctness wins over optimal code and since the optimization
> > 
> > Optimal code is also correct ;-) s/optimal/just plain broken/
> 
> Yes, bad wording. To clarify, since the optimization is now always off
> anyway (and it's also broken), I would hope that we could remove it for
> now and concentrate on fixing the existing s/r issues. Once we find that
> things are stable enough we could add back this optimization.

Arg, I guess we didn't test after moving to the opregion test?  Or maybe
it was working when it landed for S3 and not for S4?  Or broke sometime
after it landed?

Anyway this is a really valuable optimization for resume time on some
platforms, and really we shouldn't have other agents clobbering our GTT
on resume, so I'd really like to fix/re-add it asap.

Jesse