[Intel-gfx] [PATCH] drm/i915/gt: Fix rc6 on Ivybridge

[Andi Shyti]

> > > The current rc6 threshold is larger than the evaluation interval on
> > > Ivybridge; it never enters rc6. Remove the special casing so it behaves
> > > like the other gen6/gen7, and we see rc6 residencies before we manually
> > > park the system.
> > > 
> > > Closes: https://gitlab.freedesktop.org/drm/intel/issues/1114
> > > Testcase: igt/i915_pm_rc6_residency/rc6-idle #ivb
> > > Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> > > Cc: Andi Shyti <andi.shyti at intel.com>
> > > ---
> > >  drivers/gpu/drm/i915/gt/intel_rc6.c | 5 +----
> > >  1 file changed, 1 insertion(+), 4 deletions(-)
> > > 
> > > diff --git a/drivers/gpu/drm/i915/gt/intel_rc6.c b/drivers/gpu/drm/i915/gt/intel_rc6.c
> > > index 01a99fdbb3c4..682f598f7042 100644
> > > --- a/drivers/gpu/drm/i915/gt/intel_rc6.c
> > > +++ b/drivers/gpu/drm/i915/gt/intel_rc6.c
> > > @@ -226,10 +226,7 @@ static void gen6_rc6_enable(struct intel_rc6 *rc6)
> > >  
> > >       set(uncore, GEN6_RC_SLEEP, 0);
> > >       set(uncore, GEN6_RC1e_THRESHOLD, 1000);
> > > -     if (IS_IVYBRIDGE(i915))
> > > -             set(uncore, GEN6_RC6_THRESHOLD, 125000);
> > > -     else
> > > -             set(uncore, GEN6_RC6_THRESHOLD, 50000);
> > > +     set(uncore, GEN6_RC6_THRESHOLD, 50000);
> > 
> > why was is set like this in a first place?
> 
> No one knows.

I haven't found any exception either...

Reviewed-by: Andi Shyti <andi.shyti at intel.com>

Thanks,
Andi