Re: [PATCH 10/26] drm/i915: add more clock gating for VLV, allow force wake at init

["Ville Syrjälä" <ville.syrjala@linux.intel.com>]

On Fri, Mar 08, 2013 at 08:52:53AM -0800, Jesse Barnes wrote:
> On Fri, 08 Mar 2013 15:39:55 +0200
> Jani Nikula <jani.nikula@linux.intel.com> wrote:
> 
> > On Sat, 02 Mar 2013, Jesse Barnes <jbarnes@virtuousgeek.org> wrote:
> > > From: Ben Widawsky <ben@bwidawsk.net>
> > >
> > > Disable all Gunit clock gating and make set the "allow force wake" bit.
> > >
> > > Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
> > > ---
> > >  drivers/gpu/drm/i915/i915_gem.c |    4 ++++
> > >  drivers/gpu/drm/i915/i915_reg.h |    1 +
> > >  drivers/gpu/drm/i915/intel_pm.c |   10 +++++++++-
> > >  3 files changed, 14 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> > > index 8413ffc..dd67698 100644
> > > --- a/drivers/gpu/drm/i915/i915_gem.c
> > > +++ b/drivers/gpu/drm/i915/i915_gem.c
> > > @@ -4010,7 +4010,11 @@ int i915_gem_init(struct drm_device *dev)
> > >  	int ret;
> > >  
> > >  	mutex_lock(&dev->struct_mutex);
> > > +
> > > +	/* VLVA0 (potential hack), BIOS isn't actually waking us */
> > > +	I915_WRITE(VLV_GTLC_WAKE_CTRL, 1);
> > 
> > Wrap that in if IS_VALLEYVIEW(dev)? Separate this from the other hunk
> > into a separate patch?
> 
> Ah this one did sneak in, I'll factor it out and put it under an IS_VLV
> check.

Maybe I asked this already but if so I'll ask again. IIRC this thing has
an ack bit in another register. Should we poll it afterwards or are we
sure there's a long enough delay between this and when we need forcewake?

-- 
Ville Syrjälä
Intel OTC