drm/i915: Do forcewake reset on gen8

When we get control from BIOS there might be mt forcewake
bits already set. This causes us to do double mt get
without proper clear/ack sequence.

Fix this by clearing mt forcewake register on init,
like we do with older gens.

Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/i915/intel_uncore.c b/drivers/gpu/drm/i915/intel_uncore.c
index 04bd971..de72415 100644 (file)
--- a/drivers/gpu/drm/i915/intel_uncore.c
+++ b/drivers/gpu/drm/i915/intel_uncore.c
@@ -310,13 +310,13 @@ static void intel_uncore_forcewake_reset(struct drm_device *dev)
 {
        struct drm_i915_private *dev_priv = dev->dev_private;
 
-       if (IS_VALLEYVIEW(dev)) {
+       if (IS_VALLEYVIEW(dev))
                vlv_force_wake_reset(dev_priv);
-       } else if (INTEL_INFO(dev)->gen >= 6) {
+       else if (IS_GEN6(dev) || IS_GEN7(dev))
                __gen6_gt_force_wake_reset(dev_priv);
-               if (IS_IVYBRIDGE(dev) || IS_HASWELL(dev))
-                       __gen6_gt_force_wake_mt_reset(dev_priv);
-       }
+
+       if (IS_IVYBRIDGE(dev) || IS_HASWELL(dev) || IS_GEN8(dev))
+               __gen6_gt_force_wake_mt_reset(dev_priv);
 }
 
 void intel_uncore_early_sanitize(struct drm_device *dev)