drm/i915/vdsc: Add bpc check in intel_dsc_compute_params

DSC does not support bpc under 8 according to DSC 1.2a Section 2
Requirements. Return an error if that happens to be the case.

--v2
-should be bit_per_component [Mitul/Chaitanya]
-Add reference to this restriction [Chaitanya]

--v3
-Add the bpc in which we see this warning [Jani]

Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>
Reviewed-by: Chaitanya Kumar Borah <chaitanya.kumar.borah@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240926081327.1409518-2-suraj.kandpal@intel.com

diff --git a/drivers/gpu/drm/i915/display/intel_vdsc.c b/drivers/gpu/drm/i915/display/intel_vdsc.c
index 8158e3702ed5b425c0c7df2a004e1064bbb3ec08..208f117ece57e54c3939a4e0d5b98faba6a736bf 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_vdsc.c
+++ b/drivers/gpu/drm/i915/display/intel_vdsc.c
@@ -306,6 +306,12 @@ int intel_dsc_compute_params(struct intel_crtc_state *pipe_config)
 
        vdsc_cfg->bits_per_component = pipe_config->pipe_bpp / 3;
 
+       if (vdsc_cfg->bits_per_component < 8) {
+               drm_dbg_kms(&dev_priv->drm, "DSC bpc requirements not met bpc: %d\n",
+                           vdsc_cfg->bits_per_component);
+               return -EINVAL;
+       }
+
        drm_dsc_set_rc_buf_thresh(vdsc_cfg);
 
        /*