Workaround for display underrun issues with Y & Yf Tiling. Set this on all gen9 as stated by bspec. v2: proper workaround name References: HSD#2136383, BSID#857 Signed-off-by: Mika Kuoppala <mika.kuoppala@xxxxxxxxx> --- drivers/gpu/drm/i915/i915_reg.h | 3 +++ drivers/gpu/drm/i915/intel_pm.c | 4 ++++ 2 files changed, 7 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index 509238561935..280d2137f90f 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -6066,6 +6066,9 @@ enum skl_disp_power_wells { #define HSW_NDE_RSTWRN_OPT _MMIO(0x46408) #define RESET_PCH_HANDSHAKE_ENABLE (1<<4) +#define GEN8_CHICKEN_DCPR_1 _MMIO(0x46430) +#define MASK_WAKEMEM (1<<13) + #define SKL_DFSM _MMIO(0x51000) #define SKL_DFSM_CDCLK_LIMIT_MASK (3 << 23) #define SKL_DFSM_CDCLK_LIMIT_675 (0 << 23) diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index d3ad26be69dd..9ae1b0646678 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -64,6 +64,10 @@ static void gen9_init_clock_gating(struct drm_device *dev) I915_WRITE(GEN8_CONFIG0, I915_READ(GEN8_CONFIG0) | GEN9_DEFAULT_FIXES); + + /* WaEnableChickenDCPR:skl,bxt,kbl */ + I915_WRITE(GEN8_CHICKEN_DCPR_1, + I915_READ(GEN8_CHICKEN_DCPR_1) | MASK_WAKEMEM); } static void bxt_init_clock_gating(struct drm_device *dev) -- 2.5.0 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx