[Intel-gfx] [PATCH] drm/i915: Fix ICL output CSC programming

[Shankar, Uma]

>-----Original Message-----
>From: Ville Syrjala [mailto:ville.syrjala at linux.intel.com]
>Sent: Friday, April 26, 2019 12:54 AM
>To: intel-gfx at lists.freedesktop.org
>Cc: Shankar, Uma <uma.shankar at intel.com>
>Subject: [PATCH] drm/i915: Fix ICL output CSC programming
>
>From: Ville Syrjälä <ville.syrjala at linux.intel.com>
>
>When I refactored the code into its own function I accidentally misplaced the <<16
>shifts for some of the registers causing us to lose the blue channel entirely.

This looks Good.
Reviewed-by: Uma Shankar <uma.shankar at intel.com>

>We should really find a way to test this...
I guess we need to implement the pipe writeback and dump the converted
output and do a bit compare with  reference buffer. Not sure if we have any
other ways of testing it accurately.

>Cc: Uma Shankar <uma.shankar at intel.com>
>Fixes: d2c19b06d6ea ("drm/i915: Clean up ilk/icl pipe/output CSC programming")
>Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
>---
> drivers/gpu/drm/i915/intel_color.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
>diff --git a/drivers/gpu/drm/i915/intel_color.c b/drivers/gpu/drm/i915/intel_color.c
>index ca341a9e47e6..9093daabc290 100644
>--- a/drivers/gpu/drm/i915/intel_color.c
>+++ b/drivers/gpu/drm/i915/intel_color.c
>@@ -173,13 +173,13 @@ static void icl_update_output_csc(struct intel_crtc *crtc,
> 	I915_WRITE(PIPE_CSC_OUTPUT_PREOFF_LO(pipe), preoff[2]);
>
> 	I915_WRITE(PIPE_CSC_OUTPUT_COEFF_RY_GY(pipe), coeff[0] << 16 |
>coeff[1]);
>-	I915_WRITE(PIPE_CSC_OUTPUT_COEFF_BY(pipe), coeff[2]);
>+	I915_WRITE(PIPE_CSC_OUTPUT_COEFF_BY(pipe), coeff[2] << 16);
>
> 	I915_WRITE(PIPE_CSC_OUTPUT_COEFF_RU_GU(pipe), coeff[3] << 16 |
>coeff[4]);
>-	I915_WRITE(PIPE_CSC_OUTPUT_COEFF_BU(pipe), coeff[5]);
>+	I915_WRITE(PIPE_CSC_OUTPUT_COEFF_BU(pipe), coeff[5] << 16);
>
> 	I915_WRITE(PIPE_CSC_OUTPUT_COEFF_RV_GV(pipe), coeff[6] << 16 |
>coeff[7]);
>-	I915_WRITE(PIPE_CSC_OUTPUT_COEFF_BV(pipe), coeff[8]);
>+	I915_WRITE(PIPE_CSC_OUTPUT_COEFF_BV(pipe), coeff[8] << 16);
>
> 	I915_WRITE(PIPE_CSC_OUTPUT_POSTOFF_HI(pipe), postoff[0]);
> 	I915_WRITE(PIPE_CSC_OUTPUT_POSTOFF_ME(pipe), postoff[1]);
>--
>2.21.0