[PATCH v2 11/13] drm/i915: Turn off pipe CSC when it's not needed

Ville Syrjala
2019-02-05T16:09:30Z

As with pipe gamma we can avoid the potential precision loss from
the pipe csc unit when there is no need to use it. And again
we need the same logic for updating the planes.

v2: Rebase

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
---
drivers/gpu/drm/i915/intel_color.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_color.c b/drivers/gpu/drm/i915/intel_color.c
index 17fa2df3ad4d..df7c212bf68d 100644
--- a/drivers/gpu/drm/i915/intel_color.c
+++ b/drivers/gpu/drm/i915/intel_color.c
@@ -663,7 +663,8 @@ intel_color_add_affected_planes(struct intel_crtc_state *new_crtc_state)
intel_atomic_get_old_crtc_state(state, crtc);
struct intel_plane *plane;

- if (new_crtc_state->gamma_enable == old_crtc_state->gamma_enable)
+ if (new_crtc_state->gamma_enable == old_crtc_state->gamma_enable &&
+ new_crtc_state->csc_enable == old_crtc_state->csc_enable)
return 0;

for_each_intel_plane_on_crtc(&dev_priv->drm, crtc, plane) {
@@ -704,6 +705,7 @@ int intel_color_check(struct intel_crtc_state *crtc_state)
struct drm_i915_private *dev_priv = to_i915(crtc_state->base.crtc->dev);
const struct drm_property_blob *gamma_lut = crtc_state->base.gamma_lut;
const struct drm_property_blob *degamma_lut = crtc_state->base.degamma_lut;
+ bool limited_color_range = false;
int gamma_length, degamma_length;
u32 gamma_tests, degamma_tests;
int ret;
@@ -717,7 +719,11 @@ int intel_color_check(struct intel_crtc_state *crtc_state)

if (INTEL_GEN(dev_priv) >= 9 ||
IS_BROADWELL(dev_priv) || IS_HASWELL(dev_priv))
- crtc_state->csc_enable = true;
+ limited_color_range = crtc_state->limited_color_range;
+
+ crtc_state->csc_enable =
+ crtc_state->output_format != INTEL_OUTPUT_FORMAT_RGB ||
+ crtc_state->base.ctm || limited_color_range;

ret = intel_color_add_affected_planes(crtc_state);
if (ret)