diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index b4bb1ef77ddc..9d24d65f0c3e 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -568,6 +568,7 @@ #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_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index f75806e5bff5..80fce51e2f43 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -401,6 +401,14 @@ static int init_render_ring(struct intel_ring_buffer *ring) if (INTEL_INFO(dev)->gen >= 6) { I915_WRITE(INSTPM, INSTPM_FORCE_ORDERING << 16 | INSTPM_FORCE_ORDERING); + + /* From the Sandybridge PRM, volume 1 part 3, page 24: + * "If this bit is set, STCunit will have LRA as replacement + * policy. [...] This bit must be reset. LRA replacement + * policy is not supported." + */ + I915_WRITE(CACHE_MODE_0, + CM0_STC_EVICT_DISABLE_LRA_SNB << CM0_MASK_SHIFT); } return ret;