From 0f0c1924339670e9b34bbe03c181d88a8ad57e74 Mon Sep 17 00:00:00 2001 From: Eric Yang Date: Mon, 17 Dec 2018 18:28:59 -0500 Subject: [PATCH] drm/amd/display: add workaround for 4k video underflow [Why] On DCN1, there is an issue where on high BW config on single channel systems, underflow will be observed if DCC is disabled. This issue can be observed on several use cases. For this particular case, it is observed when playing 4k video on 4k desktop with video downscaled to a certain size. [How] Block MPO for this particular case, this will prevent extra BW consumed from downscaling, working around the underflow. Signed-off-by: Eric Yang Reviewed-by: Yongqiang Sun Acked-by: Leo Li Signed-off-by: Alex Deucher --- .../gpu/drm/amd/display/dc/dcn10/dcn10_resource.c | 51 ++++++++++++++++++++++ 1 file changed, 51 insertions(+) diff --git a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_resource.c b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_resource.c index 3e6a6025419a..ea0628bebe0d 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_resource.c +++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_resource.c @@ -1131,6 +1131,56 @@ static enum dc_status dcn10_validate_plane(const struct dc_plane_state *plane_st return DC_OK; } +static enum dc_status dcn10_validate_global(struct dc *dc, struct dc_state *context) +{ + int i, j; + bool video_down_scaled = false; + bool video_large = false; + bool desktop_large = false; + bool dcc_disabled = false; + + for (i = 0; i < context->stream_count; i++) { + if (context->stream_status[i].plane_count == 0) + continue; + + if (context->stream_status[i].plane_count > 2) + return false; + + for (j = 0; j < context->stream_status[i].plane_count; j++) { + struct dc_plane_state *plane = + context->stream_status[i].plane_states[j]; + + + if (plane->format >= SURFACE_PIXEL_FORMAT_VIDEO_BEGIN) { + + if (plane->src_rect.width > plane->dst_rect.width || + plane->src_rect.height > plane->dst_rect.height) + video_down_scaled = true; + + if (plane->src_rect.width >= 3840) + video_large = true; + + } else { + if (plane->src_rect.width >= 3840) + desktop_large = true; + if (!plane->dcc.enable) + dcc_disabled = true; + } + } + } + + /* + * Workaround: On DCN10 there is UMC issue that causes underflow when + * playing 4k video on 4k desktop with video downscaled and single channel + * memory + */ + if (video_large && desktop_large && video_down_scaled && dcc_disabled && + dc->dcn_soc->number_of_channels == 1) + return DC_FAIL_SURFACE_VALIDATE; + + return DC_OK; +} + static enum dc_status dcn10_get_default_swizzle_mode(struct dc_plane_state *plane_state) { enum dc_status result = DC_OK; @@ -1159,6 +1209,7 @@ static const struct resource_funcs dcn10_res_pool_funcs = { .validate_bandwidth = dcn_validate_bandwidth, .acquire_idle_pipe_for_layer = dcn10_acquire_idle_pipe_for_layer, .validate_plane = dcn10_validate_plane, + .validate_global = dcn10_validate_global, .add_stream_to_ctx = dcn10_add_stream_to_ctx, .get_default_swizzle_mode = dcn10_get_default_swizzle_mode }; -- 2.11.0