1 files changed, 12 insertions, 0 deletions

diff --git a/drivers/char/drm/i915_irq.c b/drivers/char/drm/i915_irq.c
index 4b4b2ce89863..bb8e9e9c8201 100644
--- a/drivers/char/drm/i915_irq.c
+++ b/drivers/char/drm/i915_irq.c
@@ -214,6 +214,10 @@ irqreturn_t i915_driver_irq_handler(DRM_IRQ_ARGS)
         struct drm_device *dev = (struct drm_device *) arg;
         drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
         u16 temp;
+        u32 pipea_stats, pipeb_stats;
+
+        pipea_stats = I915_READ(I915REG_PIPEASTAT);
+        pipeb_stats = I915_READ(I915REG_PIPEBSTAT);
 
         temp = I915_READ16(I915REG_INT_IDENTITY_R);
 
@@ -225,6 +229,8 @@ irqreturn_t i915_driver_irq_handler(DRM_IRQ_ARGS)
                 return IRQ_NONE;
 
         I915_WRITE16(I915REG_INT_IDENTITY_R, temp);
+        (void) I915_READ16(I915REG_INT_IDENTITY_R);
+        DRM_READMEMORYBARRIER();
 
         dev_priv->sarea_priv->last_dispatch = READ_BREADCRUMB(dev_priv);
 
@@ -252,6 +258,12 @@ irqreturn_t i915_driver_irq_handler(DRM_IRQ_ARGS)
 
                 if (dev_priv->swaps_pending > 0)
                         drm_locked_tasklet(dev, i915_vblank_tasklet);
+                I915_WRITE(I915REG_PIPEASTAT,
+                        pipea_stats|I915_VBLANK_INTERRUPT_ENABLE|
+                        I915_VBLANK_CLEAR);
+                I915_WRITE(I915REG_PIPEBSTAT,
+                        pipeb_stats|I915_VBLANK_INTERRUPT_ENABLE|
+                        I915_VBLANK_CLEAR);
         }
 
         return IRQ_HANDLED;