[PATCH AUTOSEL 6.7 68/88] drm/amd/display: Fix lightup regression with DP2 single display configs

Sasha Levin
2024-01-22T15:00:40Z

From: Michael Strauss <michael.strauss@amd.com>

[ Upstream commit 5a82b8d6c05f9b30828ede1b103b9ee5cb5c912e ]

[WHY]
Previous fix for multiple displays downstream of DP2 MST hub caused regression

[HOW]
Match sink IDs instead of sink struct addresses

Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Reviewed-by: Charlene Liu <charlene.liu@amd.com>
Acked-by: Wayne Lin <wayne.lin@amd.com>
Signed-off-by: Michael Strauss <michael.strauss@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/gpu/drm/amd/display/dc/dml2/dml2_utils.c | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/dc/dml2/dml2_utils.c b/drivers/gpu/drm/amd/display/dc/dml2/dml2_utils.c
index 2498b8341199..d6a68484153c 100644
--- a/drivers/gpu/drm/amd/display/dc/dml2/dml2_utils.c
+++ b/drivers/gpu/drm/amd/display/dc/dml2/dml2_utils.c
@@ -157,6 +157,14 @@ bool is_dp2p0_output_encoder(const struct pipe_ctx *pipe_ctx)
{
/* If this assert is hit then we have a link encoder dynamic management issue */
ASSERT(pipe_ctx->stream_res.hpo_dp_stream_enc ? pipe_ctx->link_res.hpo_dp_link_enc != NULL : true);
+ /* Count MST hubs once by treating only 1st remote sink in topology as an encoder */
+ if (pipe_ctx->stream->link && pipe_ctx->stream->link->remote_sinks[0]) {
+ return (pipe_ctx->stream_res.hpo_dp_stream_enc &&
+ pipe_ctx->link_res.hpo_dp_link_enc &&
+ dc_is_dp_signal(pipe_ctx->stream->signal) &&
+ (pipe_ctx->stream->link->remote_sinks[0]->sink_id == pipe_ctx->stream->sink->sink_id));
+ }
+
return (pipe_ctx->stream_res.hpo_dp_stream_enc &&
pipe_ctx->link_res.hpo_dp_link_enc &&
dc_is_dp_signal(pipe_ctx->stream->signal));
--
2.43.0