X-Git-Url: http://drtracing.org/?a=blobdiff_plain;f=drivers%2Fgpu%2Fdrm%2Fi915%2Fi915_irq.c;h=ae2b49969b995c0b1c7f7f76f65d2426ea003522;hb=ec6a890dfed7dd245beba5e5bcdfcffbd934c284;hp=b79619a7b78880f9823ba87de0ec888608630515;hpb=a74d70b63f1a0230831bcca3145d85ae016f9d4c;p=deliverable%2Flinux.git

diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index b79619a7b788..ae2b49969b99 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -517,7 +517,7 @@ irqreturn_t ivybridge_irq_handler(DRM_IRQ_ARGS)
 	if (de_iir & DE_PIPEA_VBLANK_IVB)
 		drm_handle_vblank(dev, 0);
 
-	if (de_iir & DE_PIPEB_VBLANK_IVB);
+	if (de_iir & DE_PIPEB_VBLANK_IVB)
 		drm_handle_vblank(dev, 1);
 
 	/* check event from PCH */
@@ -1740,6 +1740,17 @@ void ironlake_irq_preinstall(struct drm_device *dev)
 		INIT_WORK(&dev_priv->rps_work, gen6_pm_rps_work);
 
 	I915_WRITE(HWSTAM, 0xeffe);
+	if (IS_GEN6(dev)) {
+		/* Workaround stalls observed on Sandy Bridge GPUs by
+		 * making the blitter command streamer generate a
+		 * write to the Hardware Status Page for
+		 * MI_USER_INTERRUPT.  This appears to serialize the
+		 * previous seqno write out before the interrupt
+		 * happens.
+		 */
+		I915_WRITE(GEN6_BLITTER_HWSTAM, ~GEN6_BLITTER_USER_INTERRUPT);
+		I915_WRITE(GEN6_BSD_HWSTAM, ~GEN6_BSD_USER_INTERRUPT);
+	}
 
 	/* XXX hotplug from PCH */