This is a note to let you know that I've just added the patch titled drm/amd/display: Use min transition for SubVP into MPO to the 6.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-amd-display-use-min-transition-for-subvp-into-mp.patch and it can be found in the queue-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 268b4f3482aa1177f8bc7455093d2c8428ff219e Author: Alvin Lee <Alvin.Lee2@xxxxxxx> Date: Thu Oct 20 18:33:05 2022 -0400 drm/amd/display: Use min transition for SubVP into MPO [ Upstream commit 9e7d03e8b046c84e1b2973a29cd800495a5a2f09 ] [Description] - For SubVP transitioning into MPO, we want to use a minimal transition to prevent transient underflow - Transitioning a phantom pipe directly into a "real" pipe can result in underflow due to the HUBP still having it's "phantom" programming when HUBP is unblanked (have to wait for next VUPDATE of the new OTG) - Also ensure subvp pipe lock is acquired early enough for programming in dc_commit_state_no_check - When disabling phantom planes, enable phantom OTG first so the disable gets the double buffer update Reviewed-by: Aric Cyr <Aric.Cyr@xxxxxxx> Acked-by: Alan Liu <HaoPing.Liu@xxxxxxx> Signed-off-by: Alvin Lee <Alvin.Lee2@xxxxxxx> Tested-by: Daniel Wheeler <daniel.wheeler@xxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/gpu/drm/amd/display/dc/core/dc.c b/drivers/gpu/drm/amd/display/dc/core/dc.c index 5c00907099c1..5260ad6de803 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc.c @@ -1070,6 +1070,7 @@ static void disable_dangling_plane(struct dc *dc, struct dc_state *context) int i, j; struct dc_state *dangling_context = dc_create_state(dc); struct dc_state *current_ctx; + struct pipe_ctx *pipe; if (dangling_context == NULL) return; @@ -1112,6 +1113,16 @@ static void disable_dangling_plane(struct dc *dc, struct dc_state *context) } if (should_disable && old_stream) { + pipe = &dc->current_state->res_ctx.pipe_ctx[i]; + /* When disabling plane for a phantom pipe, we must turn on the + * phantom OTG so the disable programming gets the double buffer + * update. Otherwise the pipe will be left in a partially disabled + * state that can result in underflow or hang when enabling it + * again for different use. + */ + if (old_stream->mall_stream_config.type == SUBVP_PHANTOM) { + pipe->stream_res.tg->funcs->enable_crtc(pipe->stream_res.tg); + } dc_rem_all_planes_for_stream(dc, old_stream, dangling_context); disable_all_writeback_pipes_for_stream(dc, old_stream, dangling_context); @@ -1760,6 +1771,12 @@ static enum dc_status dc_commit_state_no_check(struct dc *dc, struct dc_state *c context->stream_count == 0) dc->hwss.prepare_bandwidth(dc, context); + /* When SubVP is active, all HW programming must be done while + * SubVP lock is acquired + */ + if (dc->hwss.subvp_pipe_control_lock) + dc->hwss.subvp_pipe_control_lock(dc, context, true, true, NULL, subvp_prev_use); + if (dc->debug.enable_double_buffered_dsc_pg_support) dc->hwss.update_dsc_pg(dc, context, false); @@ -1787,9 +1804,6 @@ static enum dc_status dc_commit_state_no_check(struct dc *dc, struct dc_state *c dc->hwss.wait_for_mpcc_disconnect(dc, dc->res_pool, pipe); } - if (dc->hwss.subvp_pipe_control_lock) - dc->hwss.subvp_pipe_control_lock(dc, context, true, true, NULL, subvp_prev_use); - result = dc->hwss.apply_ctx_to_hw(dc, context); if (result != DC_OK) { @@ -3576,7 +3590,6 @@ static bool could_mpcc_tree_change_for_active_pipes(struct dc *dc, struct dc_stream_status *cur_stream_status = stream_get_status(dc->current_state, stream); bool force_minimal_pipe_splitting = false; - uint32_t i; *is_plane_addition = false; @@ -3608,27 +3621,11 @@ static bool could_mpcc_tree_change_for_active_pipes(struct dc *dc, } } - /* For SubVP pipe split case when adding MPO video - * we need to add a minimal transition. In this case - * there will be 2 streams (1 main stream, 1 phantom - * stream). + /* For SubVP when adding MPO video we need to add a minimal transition. */ - if (cur_stream_status && - dc->current_state->stream_count == 2 && - stream->mall_stream_config.type == SUBVP_MAIN) { - bool is_pipe_split = false; - - for (i = 0; i < dc->res_pool->pipe_count; i++) { - if (dc->current_state->res_ctx.pipe_ctx[i].stream == stream && - (dc->current_state->res_ctx.pipe_ctx[i].bottom_pipe || - dc->current_state->res_ctx.pipe_ctx[i].next_odm_pipe)) { - is_pipe_split = true; - break; - } - } - + if (cur_stream_status && stream->mall_stream_config.type == SUBVP_MAIN) { /* determine if minimal transition is required due to SubVP*/ - if (surface_count > 0 && is_pipe_split) { + if (surface_count > 0) { if (cur_stream_status->plane_count > surface_count) { force_minimal_pipe_splitting = true; } else if (cur_stream_status->plane_count < surface_count) {