References: https://bugs.freedesktop.org/show_bug.cgi?id=50250 Signed-off-by: Jesse Barnes <jbarnes at virtuousgeek.org> --- drivers/gpu/drm/i915/i915_reg.h | 3 +++ drivers/gpu/drm/i915/intel_pm.c | 8 ++++++++ 2 files changed, 11 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index 3b75052..c75539b 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -3448,6 +3448,9 @@ #define GEN7_WA_L3_CHICKEN_MODE 0x20000000 #define GEN7_WA_DOP_CLOCK_GATING_DISABLE 0x08000000 +#define GEN7_L3SQCREG4 0xb034 +#define L3SQ_URB_READ_CAM_MATCH_DISABLE (1<<27) + /* WaCatErrorRejectionIssue */ #define GEN7_SQ_CHICKEN_MBCUNIT_CONFIG 0x9030 #define GEN7_SQ_CHICKEN_MBCUNIT_SQINTMOB (1<<11) diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 6be5910..0659317 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -3549,6 +3549,10 @@ static void ivybridge_init_clock_gating(struct drm_device *dev) I915_WRITE(GEN7_ROW_CHICKEN2, _MASKED_BIT_ENABLE(DOP_CLOCK_GATING_DISABLE)); + /* WaForceL3Serialization */ + I915_WRITE(GEN7_L3SQCREG4, I915_READ(GEN7_L3SQCREG4) & + ~L3SQ_URB_READ_CAM_MATCH_DISABLE); + /* According to the BSpec vol1g, bit 12 (RCPBUNIT) clock * gating disable must be set. Failure to set it results in * flickering pixels due to Z write ordering failures after @@ -3623,6 +3627,10 @@ static void valleyview_init_clock_gating(struct drm_device *dev) I915_WRITE(GEN7_ROW_CHICKEN2, _MASKED_BIT_ENABLE(DOP_CLOCK_GATING_DISABLE)); + /* WaForceL3Serialization */ + I915_WRITE(GEN7_L3SQCREG4, I915_READ(GEN7_L3SQCREG4) & + ~L3SQ_URB_READ_CAM_MATCH_DISABLE); + /* This is required by WaCatErrorRejectionIssue */ I915_WRITE(GEN7_SQ_CHICKEN_MBCUNIT_CONFIG, I915_READ(GEN7_SQ_CHICKEN_MBCUNIT_CONFIG) | -- 1.7.9.5