drm/amd/display: Add HDMI DSC native YCbCr422 support

[WHY && HOW]
For some HDMI OVT timing, YCbCr422 encoding fails at the DSC
bandwidth check. The root cause is our DSC policy for timing
doesn't account for HDMI YCbCr422 native support.

Cc: Mario Limonciello <[e-mail]>
Cc: Alex Deucher <[e-mail]>
Cc: [e-mail]
Reviewed-by: Chris Park <[e-mail]>
Signed-off-by: Leo Ma <[e-mail]>
Signed-off-by: Alex Hung <[e-mail]>
Tested-by: Daniel Wheeler <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c

···
 		params[count].num_slices_v = aconnector->dsc_settings.dsc_num_slices_v;
 		params[count].bpp_overwrite = aconnector->dsc_settings.dsc_bits_per_pixel;
 		params[count].compression_possible = stream->sink->dsc_caps.dsc_dec_caps.is_dsc_supported;
-		dc_dsc_get_policy_for_timing(params[count].timing, 0, &dsc_policy);
+		dc_dsc_get_policy_for_timing(params[count].timing, 0, &dsc_policy, dc_link_get_highest_encoding_format(stream->link));
 		if (!dc_dsc_compute_bandwidth_range(
 				stream->sink->ctx->dc->res_pool->dscs[0],
 				stream->sink->ctx->dc->debug.dsc_min_slice_height_override,
···
 {
 	struct dc_dsc_policy dsc_policy = {0};
 
-	dc_dsc_get_policy_for_timing(&stream->timing, 0, &dsc_policy);
+	dc_dsc_get_policy_for_timing(&stream->timing, 0, &dsc_policy, dc_link_get_highest_encoding_format(stream->link));
 	dc_dsc_compute_bandwidth_range(stream->sink->ctx->dc->res_pool->dscs[0],
 				       stream->sink->ctx->dc->debug.dsc_min_slice_height_override,
 				       dsc_policy.min_target_bpp * 16,

drivers/gpu/drm/amd/display/dc/dc_dsc.h

···
  */
 void dc_dsc_get_policy_for_timing(const struct dc_crtc_timing *timing,
 		uint32_t max_target_bpp_limit_override_x16,
-		struct dc_dsc_policy *policy);
+		struct dc_dsc_policy *policy,
+		const enum dc_link_encoding_format link_encoding);
 
 void dc_dsc_policy_set_max_target_bpp_limit(uint32_t limit);
 

drivers/gpu/drm/amd/display/dc/dsc/dc_dsc.c

···
 
 	memset(dsc_cfg, 0, sizeof(struct dc_dsc_config));
 
-	dc_dsc_get_policy_for_timing(timing, options->max_target_bpp_limit_override_x16, &policy);
+	dc_dsc_get_policy_for_timing(timing, options->max_target_bpp_limit_override_x16, &policy, link_encoding);
 	pic_width = timing->h_addressable + timing->h_border_left + timing->h_border_right;
 	pic_height = timing->v_addressable + timing->v_border_top + timing->v_border_bottom;
 
···
 
 void dc_dsc_get_policy_for_timing(const struct dc_crtc_timing *timing,
 		uint32_t max_target_bpp_limit_override_x16,
-		struct dc_dsc_policy *policy)
+		struct dc_dsc_policy *policy,
+		const enum dc_link_encoding_format link_encoding)
 {
 	uint32_t bpc = 0;