Re: [PATCH v2] drm/i915: Don't warn if we restore pm interrupts during reset

[Daniel Vetter <daniel@ffwll.ch>]

On Thu, Aug 14, 2014 at 05:45:59PM +0300, Ville Syrjälä wrote:
> On Thu, Aug 14, 2014 at 04:23:16PM +0200, Daniel Vetter wrote:
> > On Thu, Aug 14, 2014 at 03:46:43PM +0300, Mika Kuoppala wrote:
> > > We lost the software state tracking due to reset, so don't
> > > complain if it doesn't match.
> > 
> > This sounds more like gpu reset should be a bit more careful (even more
> > careful than we already are compared to earlier kernels) with making sure
> > the irq state is still sane after a reset?
> > 
> > Or what exactly is the failure mode here? The commit message lacks a bit
> > details in form of a nice text or even better: A testcase ;-)
> 
> Killing the hpd irq and gt_powersave junk from i915_reset() would be my
> suggestion here. I don't even know why the hpd stuff is still there, we
> removed all the other irq frobbery from there a while back. And last I
> looked gpu reset didn't affect the rc6/rps stuff either, though more
> testing should be done to make sure I didn't just imagine it.

No idea why the hpd_init is still in there. Could be a merge artifcat with
removing the irq handling in one patch and adding hpd_init in another. I
guess we could ditch it. The PM irq stuff is a bit more tricky since the
ring init resets them ...
-Daniel
> 
> > 
> > Thanks, Daniel
> > 
> > > 
> > > v2: fix build error
> > > 
> > > Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
> > > ---
> > >  drivers/gpu/drm/i915/intel_pm.c |    6 ++++--
> > >  1 file changed, 4 insertions(+), 2 deletions(-)
> > > 
> > > diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> > > index 12f4e14..7a1309c 100644
> > > --- a/drivers/gpu/drm/i915/intel_pm.c
> > > +++ b/drivers/gpu/drm/i915/intel_pm.c
> > > @@ -3593,7 +3593,8 @@ static void gen8_enable_rps_interrupts(struct drm_device *dev)
> > >  	struct drm_i915_private *dev_priv = dev->dev_private;
> > >  
> > >  	spin_lock_irq(&dev_priv->irq_lock);
> > > -	WARN_ON(dev_priv->rps.pm_iir);
> > > +	if (!i915_reset_in_progress(&dev_priv->gpu_error))
> > > +		WARN_ON(dev_priv->rps.pm_iir);
> > >  	gen8_enable_pm_irq(dev_priv, dev_priv->pm_rps_events);
> > >  	I915_WRITE(GEN8_GT_IIR(2), dev_priv->pm_rps_events);
> > >  	spin_unlock_irq(&dev_priv->irq_lock);
> > > @@ -3604,7 +3605,8 @@ static void gen6_enable_rps_interrupts(struct drm_device *dev)
> > >  	struct drm_i915_private *dev_priv = dev->dev_private;
> > >  
> > >  	spin_lock_irq(&dev_priv->irq_lock);
> > > -	WARN_ON(dev_priv->rps.pm_iir);
> > > +	if (!i915_reset_in_progress(&dev_priv->gpu_error))
> > > +		WARN_ON(dev_priv->rps.pm_iir);
> > >  	gen6_enable_pm_irq(dev_priv, dev_priv->pm_rps_events);
> > >  	I915_WRITE(GEN6_PMIIR, dev_priv->pm_rps_events);
> > >  	spin_unlock_irq(&dev_priv->irq_lock);
> > > -- 
> > > 1.7.9.5
> > > 
> > > _______________________________________________
> > > Intel-gfx mailing list
> > > Intel-gfx@lists.freedesktop.org
> > > http://lists.freedesktop.org/mailman/listinfo/intel-gfx
> > 
> > -- 
> > Daniel Vetter
> > Software Engineer, Intel Corporation
> > +41 (0) 79 365 57 48 - http://blog.ffwll.ch
> > _______________________________________________
> > Intel-gfx mailing list
> > Intel-gfx@lists.freedesktop.org
> > http://lists.freedesktop.org/mailman/listinfo/intel-gfx
> 
> -- 
> Ville Syrjälä
> Intel OTC

-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch