1 files changed, 25 insertions, 16 deletions

diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 77e729d4e4f0..1ab842c6032e 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -636,6 +636,19 @@ render_ring_add_request(struct intel_ring_buffer *ring,
 }
 
 static u32
+gen6_ring_get_seqno(struct intel_ring_buffer *ring)
+{
+        struct drm_device *dev = ring->dev;
+
+        /* Workaround to force correct ordering between irq and seqno writes on
+         * ivb (and maybe also on snb) by reading from a CS register (like
+         * ACTHD) before reading the status page. */
+        if (IS_GEN7(dev))
+                intel_ring_get_active_head(ring);
+        return intel_read_status_page(ring, I915_GEM_HWS_INDEX);
+}
+
+static u32
 ring_get_seqno(struct intel_ring_buffer *ring)
 {
         return intel_read_status_page(ring, I915_GEM_HWS_INDEX);
@@ -792,17 +805,6 @@ ring_add_request(struct intel_ring_buffer *ring,
 }
 
 static bool
-gen7_blt_ring_get_irq(struct intel_ring_buffer *ring)
-{
-        /* The BLT ring on IVB appears to have broken synchronization
-         * between the seqno write and the interrupt, so that the
-         * interrupt appears first.  Returning false here makes
-         * i915_wait_request() do a polling loop, instead.
-         */
-        return false;
-}
-
-static bool
 gen6_ring_get_irq(struct intel_ring_buffer *ring, u32 gflag, u32 rflag)
 {
         struct drm_device *dev = ring->dev;
@@ -811,6 +813,12 @@ gen6_ring_get_irq(struct intel_ring_buffer *ring, u32 gflag, u32 rflag)
         if (!dev->irq_enabled)
                return false;
 
+        /* It looks like we need to prevent the gt from suspending while waiting
+         * for an notifiy irq, otherwise irqs seem to get lost on at least the
+         * blt/bsd rings on ivb. */
+        if (IS_GEN7(dev))
+                gen6_gt_force_wake_get(dev_priv);
+
         spin_lock(&ring->irq_lock);
         if (ring->irq_refcount++ == 0) {
                 ring->irq_mask &= ~rflag;
@@ -835,6 +843,9 @@ gen6_ring_put_irq(struct intel_ring_buffer *ring, u32 gflag, u32 rflag)
                 ironlake_disable_irq(dev_priv, gflag);
         }
         spin_unlock(&ring->irq_lock);
+
+        if (IS_GEN7(dev))
+                gen6_gt_force_wake_put(dev_priv);
 }
 
 static bool
@@ -1341,7 +1352,7 @@ static const struct intel_ring_buffer gen6_bsd_ring = {
         .write_tail             = gen6_bsd_ring_write_tail,
         .flush                  = gen6_ring_flush,
         .add_request            = gen6_add_request,
-        .get_seqno              = ring_get_seqno,
+        .get_seqno              = gen6_ring_get_seqno,
         .irq_get                = gen6_bsd_ring_get_irq,
         .irq_put                = gen6_bsd_ring_put_irq,
         .dispatch_execbuffer    = gen6_ring_dispatch_execbuffer,
@@ -1476,7 +1487,7 @@ static const struct intel_ring_buffer gen6_blt_ring = {
         .write_tail             = ring_write_tail,
         .flush                  = blt_ring_flush,
         .add_request            = gen6_add_request,
-        .get_seqno              = ring_get_seqno,
+        .get_seqno              = gen6_ring_get_seqno,
         .irq_get                = blt_ring_get_irq,
         .irq_put                = blt_ring_put_irq,
         .dispatch_execbuffer    = gen6_ring_dispatch_execbuffer,
@@ -1499,6 +1510,7 @@ int intel_init_render_ring_buffer(struct drm_device *dev)
                 ring->flush = gen6_render_ring_flush;
                 ring->irq_get = gen6_render_ring_get_irq;
                 ring->irq_put = gen6_render_ring_put_irq;
+                ring->get_seqno = gen6_ring_get_seqno;
         } else if (IS_GEN5(dev)) {
                 ring->add_request = pc_render_add_request;
                 ring->get_seqno = pc_render_get_seqno;
@@ -1577,8 +1589,5 @@ int intel_init_blt_ring_buffer(struct drm_device *dev)
 
         *ring = gen6_blt_ring;
 
-        if (IS_GEN7(dev))
-                ring->irq_get = gen7_blt_ring_get_irq;
-
         return intel_init_ring_buffer(dev, ring);
 }