From a0a31ec4ce6a8c8bc4f4b8619b537e4a9a0ddaf1 Mon Sep 17 00:00:00 2001 From: "Leo (Sunpeng) Li" Date: Tue, 6 Feb 2018 10:20:46 -0500 Subject: [PATCH] drm/amd/display: Skip 2 frames when first reading CRC Skipping the first frame will prevent uncoooked values most of the time. However, in some unlikely cases, the second frame will be uncooked as well. Signed-off-by: Leo (Sunpeng) Li Reviewed-by: Harry Wentland Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h | 2 +- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crc.c | 12 ++++++------ 2 files changed, 7 insertions(+), 7 deletions(-) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h index ed93960..aa7df57 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h @@ -198,7 +198,7 @@ struct dm_crtc_state { struct drm_crtc_state base; struct dc_stream_state *stream; - bool crc_first_skipped; + int crc_skip_count; bool crc_enabled; }; diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crc.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crc.c index 55aa379..52f2c01 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crc.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crc.c @@ -84,8 +84,8 @@ int amdgpu_dm_crtc_set_crc_source(struct drm_crtc *crtc, const char *src_name, } *values_cnt = 3; - /* Reset crc_skipped flag on dm state */ - crtc_state->crc_first_skipped = false; + /* Reset crc_skipped on dm state */ + crtc_state->crc_skip_count = 0; return 0; } @@ -109,11 +109,11 @@ void amdgpu_dm_crtc_handle_crc_irq(struct drm_crtc *crtc) /* * Since flipping and crc enablement happen asynchronously, we - more * often than not - will be returning an 'uncooked' crc on first frame. - * Probably because hw isn't ready yet. Simply skip the first crc - * value. + * Probably because hw isn't ready yet. For added security, skip the + * first two CRC values. */ - if (!crtc_state->crc_first_skipped) { - crtc_state->crc_first_skipped = true; + if (crtc_state->crc_skip_count < 2) { + crtc_state->crc_skip_count += 1; return; } -- 2.7.4