drm/i915/chv: Add basic PM interrupt support for CHV

Enabled PM interrupt programming for CHV. Re-using gen8 code and extending same for CHV.
Signed-off-by: Deepak S <deepak.s@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_irq.c

@@ -1407,7 +1407,7 @@ static void gen6_pm_rps_work(struct work_struct *work)
 	spin_lock_irq(&dev_priv->irq_lock);
 	pm_iir = dev_priv->rps.pm_iir;
 	dev_priv->rps.pm_iir = 0;
-	if (IS_BROADWELL(dev_priv->dev))
+	if (IS_BROADWELL(dev_priv->dev) || IS_CHERRYVIEW(dev_priv->dev))
 		bdw_enable_pm_irq(dev_priv, dev_priv->pm_rps_events);
 	else {
 		/* Make sure not to corrupt PMIMR state used by ringbuffer */

drivers/gpu/drm/i915/intel_pm.c

@@ -3392,6 +3392,8 @@ static void cherryview_disable_rps(struct drm_device *dev)
 	struct drm_i915_private *dev_priv = dev->dev_private;
 
 	I915_WRITE(GEN6_RC_CONTROL, 0);
+
+	gen8_disable_rps_interrupts(dev);
 }
 
 static void valleyview_disable_rps(struct drm_device *dev)
@@ -4109,6 +4111,8 @@ static void cherryview_enable_rps(struct drm_device *dev)
 
 	valleyview_set_rps(dev_priv->dev, dev_priv->rps.efficient_freq);
 
+	gen8_enable_rps_interrupts(dev);
+
 	gen6_gt_force_wake_put(dev_priv, FORCEWAKE_ALL);
 }