[Intel-gfx] [PATCH 5/5] drm/i915: set stc evict disable lra evict w/a

[Daniel Vetter]

Our workaround list kindly lists that this new default value needs to
be updated in Bspec. Naturally, this did not happen.

Acked-by: Ben Widawsky <ben at bwidawsk.net>
Signed-Off-by: Daniel Vetter <daniel.vetter at ffwll.ch>
---
 drivers/gpu/drm/i915/i915_reg.h      |    1 +
 drivers/gpu/drm/i915/intel_display.c |    4 ++++
 2 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index cd2d2c7..0ff4456 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -576,6 +576,7 @@
 #define   CM0_MASK_SHIFT          16
 #define   CM0_IZ_OPT_DISABLE      (1<<6)
 #define   CM0_ZR_OPT_DISABLE      (1<<5)
+#define	  CM0_STC_EVICT_DISABLE_LRA_SNB	(1<<5)
 #define   CM0_DEPTH_EVICT_DISABLE (1<<4)
 #define   CM0_COLOR_EVICT_DISABLE (1<<3)
 #define   CM0_DEPTH_WRITE_DISABLE (1<<1)
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 083c741..7d96f53 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -8556,6 +8556,10 @@ static void gen6_init_clock_gating(struct drm_device *dev)
 	I915_WRITE(WM2_LP_ILK, 0);
 	I915_WRITE(WM1_LP_ILK, 0);
 
+	/* clear masked bit */
+	I915_WRITE(CACHE_MODE_0,
+		   CM0_STC_EVICT_DISABLE_LRA_SNB << CM0_MASK_SHIFT);
+
 	I915_WRITE(GEN6_UCGCTL1,
 		   I915_READ(GEN6_UCGCTL1) |
 		   GEN6_BLBUNIT_CLOCK_GATE_DISABLE |
-- 
1.7.7.6