From: Yihan Zhu Yihan.Zhu@amd.com

[Why] No check on head pipe during the dml to dc hw mapping will allow illegal pipe usage. This will result in a wrong pipe topology to cause mpcc tree totally mess up then cause a display hang.

[How] Avoid to use the pipe is head in all check and avoid ODM slice during preferred pipe check.

Cc: stable@vger.kernel.org Reviewed-by: Nicholas Kazlauskas nicholas.kazlauskas@amd.com Signed-off-by: Yihan Zhu Yihan.Zhu@amd.com Signed-off-by: Hamza Mahfooz hamza.mahfooz@amd.com --- .../display/dc/dml2/dml2_dc_resource_mgmt.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/dc/dml2/dml2_dc_resource_mgmt.c b/drivers/gpu/drm/amd/display/dc/dml2/dml2_dc_resource_mgmt.c index 6eccf0241d85..9be9ed7e01d3 100644 --- a/drivers/gpu/drm/amd/display/dc/dml2/dml2_dc_resource_mgmt.c +++ b/drivers/gpu/drm/amd/display/dc/dml2/dml2_dc_resource_mgmt.c @@ -258,12 +258,23 @@ static unsigned int find_preferred_pipe_candidates(const struct dc_state *existi * However this condition comes with a caveat. We need to ignore pipes that will * require a change in OPP but still have the same stream id. For example during * an MPC to ODM transiton. + * + * Adding check to avoid pipe select on the head pipe by utilizing dc resource + * helper function resource_get_primary_dpp_pipe and comparing the pipe index. */ if (existing_state) { for (i = 0; i < pipe_count; i++) { if (existing_state->res_ctx.pipe_ctx[i].stream && existing_state->res_ctx.pipe_ctx[i].stream->stream_id == stream_id) { + struct pipe_ctx *head_pipe = + resource_get_primary_dpp_pipe(&existing_state->res_ctx.pipe_ctx[i]); + + // we should always respect the head pipe from selection + if (head_pipe && head_pipe->pipe_idx == i) + continue; if (existing_state->res_ctx.pipe_ctx[i].plane_res.hubp && - existing_state->res_ctx.pipe_ctx[i].plane_res.hubp->opp_id != i) + existing_state->res_ctx.pipe_ctx[i].plane_res.hubp->opp_id != i && + (existing_state->res_ctx.pipe_ctx[i].prev_odm_pipe || + existing_state->res_ctx.pipe_ctx[i].next_odm_pipe)) continue;

preferred_pipe_candidates[num_preferred_candidates++] = i; @@ -292,6 +303,12 @@ static unsigned int find_last_resort_pipe_candidates(const struct dc_state *exis */ if (existing_state) { for (i = 0; i < pipe_count; i++) { + struct pipe_ctx *head_pipe = + resource_get_primary_dpp_pipe(&existing_state->res_ctx.pipe_ctx[i]); + + // we should always respect the head pipe from selection + if (head_pipe && head_pipe->pipe_idx == i) + continue; if ((existing_state->res_ctx.pipe_ctx[i].plane_res.hubp && existing_state->res_ctx.pipe_ctx[i].plane_res.hubp->opp_id != i) || existing_state->res_ctx.pipe_ctx[i].stream_res.tg)