drm/i915: paper over missed irq issues with force wake voodoo

[pandora-kernel.git] / drivers / gpu / drm / i915 / intel_ringbuffer.c

diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index ca70e2f..30a9af9 100644 (file)
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -630,6 +630,19 @@ render_ring_add_request(struct intel_ring_buffer *ring,
        return 0;
 }
 
+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)
 {
@@ -795,6 +808,12 @@ 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;
@@ -819,6 +838,9 @@ 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
@@ -1316,7 +1338,7 @@ 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,
@@ -1451,7 +1473,7 @@ 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,
@@ -1474,6 +1496,7 @@ 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;