drm/i915: prepare csc unit for YCBCR420 output
To support ycbcr output, we need a pipe CSC block to do
RGB->YCBCR conversion.
Current Intel platforms have only one pipe CSC unit, so
we can either do color correction using it, or we can perform
RGB->YCBCR conversion.
This function adds a csc handler, which uses recommended bspec
values to perform RGB->YCBCR conversion (target color space BT709)
V2: Rebase
V3: Rebase
V4: Rebase
V5: Addressed review comments from Ander
- Remove extra line added in the patch
- Add the spec details in the commit message
- Combine two if(cond) while calling intel_crtc_compute_config
V6: Handle YCBCR420 outputs only (Ville)
V7: Addressed review comments from Ville:
- Add description about target colorspace
- Remove the comments from CSC function
- DRM_DEBUG->DEBUG_KMS for atomic failure due to CSC unit busy
- Remove unnecessary debug message about YCBCR420 possibe
V8: Addressed review comments from Ville:
- Remove extra comment, not required.
- Do not add extra variable for CTM, reuse pipe_config
Added r-b from Ville
V9: Remove extra whitespace (Imre)
V10: Added r-b from Imre
Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Ander Conselvan de Oliveira <conselvan2@gmail.com>
Cc: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjala <ville.syrjala@linux.intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Shashank Sharma <shashank.sharma@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1500650709-14447-5-git-send-email-shashank.sharma@intel.com
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 146b8173..f7b128c 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -6140,6 +6140,16 @@ static int intel_crtc_compute_config(struct intel_crtc *crtc,
return -EINVAL;
}
+ if (pipe_config->ycbcr420 && pipe_config->base.ctm) {
+ /*
+ * There is only one pipe CSC unit per pipe, and we need that
+ * for output conversion from RGB->YCBCR. So if CTM is already
+ * applied we can't support YCBCR420 output.
+ */
+ DRM_DEBUG_KMS("YCBCR420 and CTM together are not possible\n");
+ return -EINVAL;
+ }
+
/*
* Pipe horizontal size must be even in:
* - DVO ganged mode