drm/i915: Track the enabled PM interrupts in dev_priv.

When we use different rps events for different platforms or due to wa,
we might end up needing this logic in a lot of places. Instead of
this let's use a variable in dev_priv to track the enabled PM
interrupts.

v2: Initialize pm_rps_events in intel_irq_init() (Ville).

Signed-off-by: Deepak S <deepak.s@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
[danvet: Frob the commit message a bit since the English was a bit too
garbled ;-) ]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index fd68f93..faa059a 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -3160,7 +3160,8 @@
 	struct drm_i915_private *dev_priv = dev->dev_private;
 
 	I915_WRITE(GEN6_PMINTRMSK, 0xffffffff);
-	I915_WRITE(GEN6_PMIER, I915_READ(GEN6_PMIER) & ~GEN6_PM_RPS_EVENTS);
+	I915_WRITE(GEN6_PMIER, I915_READ(GEN6_PMIER) &
+				~dev_priv->pm_rps_events);
 	/* Complete PM interrupt masking here doesn't race with the rps work
 	 * item again unmasking PM interrupts because that is using a different
 	 * register (PMIMR) to mask PM interrupts. The only risk is in leaving
@@ -3170,7 +3171,7 @@
 	dev_priv->rps.pm_iir = 0;
 	spin_unlock_irq(&dev_priv->irq_lock);
 
-	I915_WRITE(GEN6_PMIIR, GEN6_PM_RPS_EVENTS);
+	I915_WRITE(GEN6_PMIIR, dev_priv->pm_rps_events);
 }
 
 static void gen6_disable_rps(struct drm_device *dev)
@@ -3232,12 +3233,12 @@
 
 	spin_lock_irq(&dev_priv->irq_lock);
 	WARN_ON(dev_priv->rps.pm_iir);
-	snb_enable_pm_irq(dev_priv, GEN6_PM_RPS_EVENTS);
-	I915_WRITE(GEN6_PMIIR, GEN6_PM_RPS_EVENTS);
+	snb_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);
 
 	/* only unmask PM interrupts we need. Mask all others. */
-	enabled_intrs = GEN6_PM_RPS_EVENTS;
+	enabled_intrs = dev_priv->pm_rps_events;
 
 	/* IVB and SNB hard hangs on looping batchbuffer
 	 * if GEN6_PM_UP_EI_EXPIRED is masked.