[Intel-gfx] [RFC 3/3] i915: Drop vblank_offdelay

[Matthew Garrett]

Sandybridge, at least, seems to manage without any vblank offdelay.
Dropping this reduces the number of wakeups on an otherwise idle system
dramatically.

Signed-off-by: Matthew Garrett <mjg at redhat.com>
---
 drivers/gpu/drm/i915/i915_dma.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index a9533c5..46e7172 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -1917,6 +1917,9 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
 		goto free_priv;
 	}
 
+	/* vblank is reliable */
+	dev->vblank_offdelay = 0;
+
 	/* overlay on gen2 is broken and can't address above 1G */
 	if (IS_GEN2(dev))
 		dma_set_coherent_mask(&dev->pdev->dev, DMA_BIT_MASK(30));
-- 
1.7.7.1