[PATCH v6 13/13] drm/amd/display: Recalculate VCPI slots for new DSC connectors

[mikita.lipski at amd.com]

From: Mikita Lipski <mikita.lipski at amd.com>

Since for DSC MST connector's PBN is claculated differently
due to compression, we have to recalculate both PBN and
VCPI slots for that connector.

The function iterates through all the active streams to
find, which have DSC enabled, then recalculates PBN for
it and calls drm_dp_helper_update_vcpi_slots_for_dsc to
update connector's VCPI slots.

v2: use drm_dp_mst_atomic_enable_dsc per port to
enable/disable DSC

Cc: Jerry Zuo <Jerry.Zuo at amd.com>
Cc: Harry Wentland <harry.wentland at amd.com>
Cc: Lyude Paul <lyude at redhat.com>
Signed-off-by: Mikita Lipski <mikita.lipski at amd.com>
---
 .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 56 +++++++++++++++++--
 1 file changed, 51 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 609020a0549e..9e6dd82506f7 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -4958,6 +4958,49 @@ const struct drm_encoder_helper_funcs amdgpu_dm_encoder_helper_funcs = {
 	.atomic_check = dm_encoder_helper_atomic_check
 };
 
+static int dm_update_mst_vcpi_slots_for_dsc(struct drm_atomic_state *state,
+					    struct dc_state *dc_state)
+{
+	struct dc_stream_state *stream;
+	struct amdgpu_dm_connector *aconnector;
+	struct dm_connector_state *dm_conn_state;
+	int i = 0, clock = 0, bpp = 0;
+	int vcpi = 0, pbn = 0;
+
+	for (i = 0; i < dc_state->stream_count; i++) {
+
+		stream = dc_state->streams[i];
+
+		if (!stream)
+			continue;
+
+		aconnector = (struct amdgpu_dm_connector *)stream->dm_stream_context;
+		dm_conn_state = to_dm_connector_state(aconnector->base.state);
+
+		if (!aconnector->port)
+			continue;
+
+		if (stream->timing.flags.DSC != 1) {
+			drm_dp_mst_atomic_enable_dsc(state, aconnector->port, dm_conn_state->pbn, false);
+			continue;
+		}
+
+		bpp = convert_dc_color_depth_into_bpc(stream->timing.display_color_depth)* 3;
+		clock = stream->timing.pix_clk_100hz / 10;
+		pbn =  drm_dp_calc_pbn_mode(clock, bpp, true);
+		vcpi = drm_dp_mst_atomic_enable_dsc(state, aconnector->port, pbn, true);
+
+		if (vcpi < 0)
+			return vcpi;
+
+		if (vcpi > 0 && dm_conn_state->vcpi_slots != vcpi) {
+			dm_conn_state->pbn = pbn;
+			dm_conn_state->vcpi_slots = vcpi;
+		}
+	}
+	return 0;
+}
+
 static void dm_drm_plane_reset(struct drm_plane *plane)
 {
 	struct dm_plane_state *amdgpu_state = NULL;
@@ -7991,11 +8034,6 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
 	if (ret)
 		goto fail;
 
-	/* Perform validation of MST topology in the state*/
-	ret = drm_dp_mst_atomic_check(state);
-	if (ret)
-		goto fail;
-
 	if (state->legacy_cursor_update) {
 		/*
 		 * This is a fast cursor update coming from the plane update
@@ -8067,6 +8105,10 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
 #ifdef CONFIG_DRM_AMD_DC_DSC_SUPPORT
 		if (!compute_mst_dsc_configs_for_state(state, dm_state->context))
 			goto fail;
+
+		ret = dm_update_mst_vcpi_slots_for_dsc(state, dm_state->context);
+		if (ret)
+			goto fail;
 #endif
 		if (dc_validate_global_state(dc, dm_state->context, false) != DC_OK) {
 			ret = -EINVAL;
@@ -8096,6 +8138,10 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
 				dc_retain_state(old_dm_state->context);
 		}
 	}
+	/* Perform validation of MST topology in the state*/
+	ret = drm_dp_mst_atomic_check(state);
+	if (ret)
+		goto fail;
 
 	/* Store the overall update type for use later in atomic check. */
 	for_each_new_crtc_in_state (state, crtc, new_crtc_state, i) {
-- 
2.17.1