[Intel-gfx] [PATCH] drm/i915/bdw: Use timeout mode for RC6 on bdw

[Imre Deak]

On Wed, 2014-04-30 at 13:41 -0700, Ben Widawsky wrote:
> On Wed, Apr 30, 2014 at 01:34:36PM -0700, Kristen Carlson Accardi wrote:
> > On Tue, 29 Apr 2014 22:31:49 -0700
> > Ben Widawsky <ben at bwidawsk.net> wrote:
> > 
> > > On Wed, Apr 09, 2014 at 11:44:06AM -0700, Tom O'Rourke wrote:
> > > > Higher RC6 residency is observed using timeout mode
> > > > instead of EI mode.  This applies to Broadwell only.
> > > > The difference is particularly noticeable with video
> > > > playback.
> > > > 
> > > > Issue: VIZ-3778
> > > > Change-Id: I62bb12e21caf19651034826b45cde7f73a80938d
> > > > Signed-off-by: Tom O'Rourke <Tom.O'Rourke at intel.com>
> > > 
> > > I've merged this one to my bdw-rc6 branch, and therefore my broadwell
> > > branch. Hopefully Kristen will see some improvement.
> > 
> > Unfortunately, I built your bdw-rc6 branch along with the revert
> > I need to get my panel to work, and I get zero rc6 residency.  Do I
> > have to explicitly enable it?
> 
> I'm not actually sure. You can try it and let me know. I haven't had any
> time to verify the rebase. We can check my hack.

Note that in -nightly you also have to update sanitize_rc6_option()
along with intel_enable_gt_powersave() and intel_disable_gt_powersave()
since atm these keep RC6 disabled on BDW.

--Imre