From: Ville Syrj?l? <ville.syrjala at linux.intel.com> According to BSpec, trickle feed should be disabled for BW and mobile CL. Those constraints seem to match all of our gen4 chipsets. Trickle feed is disabled via the MI_ARB_STATE register instead of per plane controls on gen4. Reviewed-by: Chris Wilson <chris at chris-wilson.co.uk> Signed-off-by: Ville Syrj?l? <ville.syrjala at linux.intel.com> --- drivers/gpu/drm/i915/intel_pm.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 47f3c48..2948764 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -4944,6 +4944,8 @@ static void crestline_init_clock_gating(struct drm_device *dev) I915_WRITE(DSPCLK_GATE_D, 0); I915_WRITE(RAMCLK_GATE_D, 0); I915_WRITE16(DEUC, 0); + I915_WRITE(MI_ARB_STATE, + _MASKED_BIT_ENABLE(MI_ARB_DISPLAY_TRICKLE_FEED_DISABLE)); } static void broadwater_init_clock_gating(struct drm_device *dev) @@ -4956,6 +4958,8 @@ static void broadwater_init_clock_gating(struct drm_device *dev) I965_ISC_CLOCK_GATE_DISABLE | I965_FBC_CLOCK_GATE_DISABLE); I915_WRITE(RENCLK_GATE_D2, 0); + I915_WRITE(MI_ARB_STATE, + _MASKED_BIT_ENABLE(MI_ARB_DISPLAY_TRICKLE_FEED_DISABLE)); } static void gen3_init_clock_gating(struct drm_device *dev) -- 1.8.1.5
