[Intel-gfx] [PATCH 1/2] drm/i915: don't save/restore CACHE_MODE_0 on gen7+

[Jesse Barnes]

On gen7+, CACHE_MODE_0 moved, so we're clobbering some other reg rather
than restoring CACHE_MODE_0.  Don't do that.

Signed-off-by: Jesse Barnes <jbarnes at virtuousgeek.org>
---
 drivers/gpu/drm/i915/i915_suspend.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_suspend.c b/drivers/gpu/drm/i915/i915_suspend.c
index 97ca8f1..98790c7 100644
--- a/drivers/gpu/drm/i915/i915_suspend.c
+++ b/drivers/gpu/drm/i915/i915_suspend.c
@@ -398,7 +398,8 @@ int i915_save_state(struct drm_device *dev)
 	intel_disable_gt_powersave(dev);
 
 	/* Cache mode state */
-	dev_priv->regfile.saveCACHE_MODE_0 = I915_READ(CACHE_MODE_0);
+	if (INTEL_INFO(dev)->gen < 7)
+		dev_priv->regfile.saveCACHE_MODE_0 = I915_READ(CACHE_MODE_0);
 
 	/* Memory Arbitration state */
 	dev_priv->regfile.saveMI_ARB_STATE = I915_READ(MI_ARB_STATE);
@@ -447,7 +448,9 @@ int i915_restore_state(struct drm_device *dev)
 	}
 
 	/* Cache mode state */
-	I915_WRITE(CACHE_MODE_0, dev_priv->regfile.saveCACHE_MODE_0 | 0xffff0000);
+	if (INTEL_INFO(dev)->gen < 7)
+		I915_WRITE(CACHE_MODE_0, dev_priv->regfile.saveCACHE_MODE_0 |
+			   0xffff0000);
 
 	/* Memory arbitration state */
 	I915_WRITE(MI_ARB_STATE, dev_priv->regfile.saveMI_ARB_STATE | 0xffff0000);
-- 
1.8.3.1