drm/amd/display: Add dynamic link encoder selection.

[Why]
Some display endpoints may be programmably mapped to compatible link
encoders. The assignment of link encoders to links has to be dynamic to
accommodate the increased flexibility in comparison to conventional
display endpoints.

[How]
- Add link encoder assignment tracking variables.
- Execute link encoder assignment algorithm before enabling link and
release link encoders from links once they are disabled.

Signed-off-by: Jimmy Kizito <Jimmy.Kizito@amd.com>
Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Anson Jacob <Anson.Jacob@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/display/dc/dc_stream.h b/drivers/gpu/drm/amd/display/dc/dc_stream.h
index e747370fc43b..2bc057e0b447 100644
--- a/drivers/gpu/drm/amd/display/dc/dc_stream.h
+++ b/drivers/gpu/drm/amd/display/dc/dc_stream.h
@@ -136,6 +136,10 @@ struct dc_stream_state {
 	struct dc_sink *sink;
 
 	struct dc_link *link;
+	/* For dynamic link encoder assignment, update the link encoder assigned to
+	 * a stream via the volatile dc_state rather than the static dc_link.
+	 */
+	struct link_encoder *link_enc;
 	struct dc_panel_patch sink_patches;
 	union display_content_support content_support;
 	struct dc_crtc_timing timing;