[Intel-gfx] [PATCH] drm/i915: Re-enable GGTT earlier during resume on pre-gen6 platforms

[Ville Syrjälä]

On Fri, May 06, 2016 at 09:22:49PM +0100, Chris Wilson wrote:
> On Fri, May 06, 2016 at 09:35:55PM +0300, ville.syrjala at linux.intel.com wrote:
> > @@ -730,9 +730,14 @@ int i915_suspend_switcheroo(struct drm_device *dev, pm_message_t state)
> >  static int i915_drm_resume(struct drm_device *dev)
> >  {
> >  	struct drm_i915_private *dev_priv = dev->dev_private;
> > +	int ret;
> >  
> >  	disable_rpm_wakeref_asserts(dev_priv);
> >  
> > +	ret = i915_ggtt_enable_hw(dev);
> > +	if (ret)
> > +		DRM_ERROR("failed to re-enable GGTT\n");
> 
> Would it not be fatal for resume as well? Failure means we can't use the
> GGTT, so all subsequent writes will be going into a random address.

Yeah, I assume things would blow up. The question is however, what can
we do in this case? We'd basically have to shut the entire driver down.
I don't think we have a way to do that?

-- 
Ville Syrjälä
Intel OTC