1 files changed, 36 insertions, 19 deletions

diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 654d42fabec8..c3673581db58 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -170,37 +170,54 @@ irqreturn_t i915_driver_irq_handler(DRM_IRQ_ARGS)
         drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
         u32 iir, new_iir;
         u32 pipea_stats, pipeb_stats;
+        u32 vblank_status;
+        u32 vblank_enable;
         int vblank = 0;
         unsigned long irqflags;
+        int irq_received;
+        int ret = IRQ_NONE;
 
         atomic_inc(&dev_priv->irq_received);
 
         iir = I915_READ(IIR);
 
-        if (iir == 0)
-                return IRQ_NONE;
+        if (IS_I965G(dev)) {
+                vblank_status = I915_START_VBLANK_INTERRUPT_STATUS;
+                vblank_enable = PIPE_START_VBLANK_INTERRUPT_ENABLE;
+        } else {
+                vblank_status = I915_VBLANK_INTERRUPT_STATUS;
+                vblank_enable = I915_VBLANK_INTERRUPT_ENABLE;
+        }
 
-        do {
-                pipea_stats = 0;
-                pipeb_stats = 0;
+        for (;;) {
+                irq_received = iir != 0;
+
+                /* Can't rely on pipestat interrupt bit in iir as it might
+                 * have been cleared after the pipestat interrupt was received.
+                 * It doesn't set the bit in iir again, but it still produces
+                 * interrupts (for non-MSI).
+                 */
+                spin_lock_irqsave(&dev_priv->user_irq_lock, irqflags);
+                pipea_stats = I915_READ(PIPEASTAT);
+                pipeb_stats = I915_READ(PIPEBSTAT);
                 /*
                  * Clear the PIPE(A|B)STAT regs before the IIR
                  */
-                if (iir & I915_DISPLAY_PIPE_A_EVENT_INTERRUPT) {
-                        spin_lock_irqsave(&dev_priv->user_irq_lock, irqflags);
-                        pipea_stats = I915_READ(PIPEASTAT);
+                if (pipea_stats & 0x8000ffff) {
                         I915_WRITE(PIPEASTAT, pipea_stats);
-                        spin_unlock_irqrestore(&dev_priv->user_irq_lock,
-                                               irqflags);
+                        irq_received = 1;
                 }
 
-                if (iir & I915_DISPLAY_PIPE_B_EVENT_INTERRUPT) {
-                        spin_lock_irqsave(&dev_priv->user_irq_lock, irqflags);
-                        pipeb_stats = I915_READ(PIPEBSTAT);
+                if (pipeb_stats & 0x8000ffff) {
                         I915_WRITE(PIPEBSTAT, pipeb_stats);
-                        spin_unlock_irqrestore(&dev_priv->user_irq_lock,
-                                               irqflags);
+                        irq_received = 1;
                 }
+                spin_unlock_irqrestore(&dev_priv->user_irq_lock, irqflags);
+
+                if (!irq_received)
+                        break;
+
+                ret = IRQ_HANDLED;
 
                 I915_WRITE(IIR, iir);
                 new_iir = I915_READ(IIR); /* Flush posted writes */
@@ -214,12 +231,12 @@ irqreturn_t i915_driver_irq_handler(DRM_IRQ_ARGS)
                         DRM_WAKEUP(&dev_priv->irq_queue);
                 }
 
-                if (pipea_stats & I915_VBLANK_INTERRUPT_STATUS) {
+                if (pipea_stats & vblank_status) {
                         vblank++;
                         drm_handle_vblank(dev, 0);
                 }
 
-                if (pipeb_stats & I915_VBLANK_INTERRUPT_STATUS) {
+                if (pipeb_stats & vblank_status) {
                         vblank++;
                         drm_handle_vblank(dev, 1);
                 }
@@ -244,9 +261,9 @@ irqreturn_t i915_driver_irq_handler(DRM_IRQ_ARGS)
                  * stray interrupts.
                  */
                 iir = new_iir;
-        } while (iir != 0);
+        }
 
-        return IRQ_HANDLED;
+        return ret;
 }
 
 static int i915_emit_irq(struct drm_device * dev)