[PATCH] drm/amd/display: fix PSR-SU/DSC interoperability support

[Hamza Mahfooz]

Currently, there are issues with enabling PSR-SU + DSC. This stems from
the fact that DSC imposes a slice height on transmitted video data and
we are not conforming to that slice height in PSR-SU regions. So, pass
slice_height into su_y_granularity to feed the DSC slice height into
PSR-SU code.

Signed-off-by: Hamza Mahfooz <hamza.mahfooz at amd.com>
---
 .../drm/amd/display/amdgpu_dm/amdgpu_dm_psr.c | 38 +++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_psr.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_psr.c
index 26291db0a3cf..55acadf0b63f 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_psr.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_psr.c
@@ -53,6 +53,41 @@ static bool link_supports_psrsu(struct dc_link *link)
 	return true;
 }
 
+static bool psr_su_set_y_granularity(struct dc *dc, struct dc_link *link,
+				     struct dc_stream_state *stream,
+				     struct psr_config *config)
+{
+	u16 pic_height;
+	u8 slice_height;
+
+	if (!dc->caps.edp_dsc_support ||
+	    link->panel_config.dsc.disable_dsc_edp ||
+	    !link->dpcd_caps.dsc_caps.dsc_basic_caps.fields.dsc_support.DSC_SUPPORT ||
+	    !stream->timing.dsc_cfg.num_slices_v)
+		return true;
+
+	pic_height = stream->timing.v_addressable +
+		stream->timing.v_border_top + stream->timing.v_border_bottom;
+	slice_height = pic_height / stream->timing.dsc_cfg.num_slices_v;
+
+	if (slice_height) {
+		if (config->su_y_granularity &&
+		    (slice_height % config->su_y_granularity)) {
+			WARN(1,
+			     "%s: dsc: %d, slice_height: %d, num_slices_v: %d\n",
+			     __func__,
+			     stream->sink->dsc_caps.dsc_dec_caps.is_dsc_supported,
+			     slice_height,
+			     stream->timing.dsc_cfg.num_slices_v);
+			return false;
+		}
+
+		config->su_y_granularity = slice_height;
+	}
+
+	return true;
+}
+
 /*
  * amdgpu_dm_set_psr_caps() - set link psr capabilities
  * @link: link
@@ -122,6 +157,9 @@ bool amdgpu_dm_link_setup_psr(struct dc_stream_state *stream)
 		psr_config.allow_multi_disp_optimizations =
 			(amdgpu_dc_feature_mask & DC_PSR_ALLOW_MULTI_DISP_OPT);
 
+		if (!psr_su_set_y_granularity(dc, link, stream, &psr_config))
+			return false;
+
 		ret = dc_link_setup_psr(link, stream, &psr_config, &psr_context);
 
 	}
-- 
2.38.1