drm/i915/vlv: use a lower RC6 timeout on VLV

We use timeout mode, and we need to lower the timeout to get good RC6
residency when loads are running.  This gets me from 0% residency during
glxgears to 77%, which is a pretty good improvement.  This value also
matches the current BWG recommentations.

Tested-by: "Meng, Mengmeng" <mengmeng.meng@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Deepak S <deepak.s@inel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 1659265a7f7a7e4fe1be092f590fb2221ff9bafa..2d74ae83b17569682de492a0a934f2138c051e6c 100644 (file)
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -4110,7 +4110,7 @@ static void valleyview_enable_rps(struct drm_device *dev)
        for_each_ring(ring, dev_priv, i)
                I915_WRITE(RING_MAX_IDLE(ring->mmio_base), 10);
 
-       I915_WRITE(GEN6_RC6_THRESHOLD, 0xc350);
+       I915_WRITE(GEN6_RC6_THRESHOLD, 0x557);
 
        /* allows RC6 residency counter to work */
        I915_WRITE(VLV_COUNTER_CONTROL,