This is a note to let you know that I've just added the patch titled drm/amd/display: Fix unstable HPCP compliance on Chrome Barcelo to the 5.14-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-fix-unstable-hpcp-compliance-on-chro.patch and it can be found in the queue-5.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit fc2904418b0e7ad8b98ef818b8d459948a30273d Author: Qingqing Zhuo <qingqing.zhuo@xxxxxxx> Date: Fri Aug 27 06:58:38 2021 -0400 drm/amd/display: Fix unstable HPCP compliance on Chrome Barcelo [ Upstream commit 4e00a434a08e0654a4dd9347485d9ec85deee1ef ] [Why] Intermittently, there presents two occurrences of 0 stream commits in a single HPD event. Current HDCP sequence does not consider such scenerio, and will thus disable HDCP. [How] Add condition check to include stream remove and re-enable case for HDCP enable. Reviewed-by: Bhawanpreet Lakha <bhawanpreet.lakha@xxxxxxx> Acked-by: Mikita Lipski <mikita.lipski@xxxxxxx> Signed-off-by: Qingqing Zhuo <qingqing.zhuo@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/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c index a4a4bb43c108..e7cf79b386da 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -8051,8 +8051,26 @@ static bool is_content_protection_different(struct drm_connector_state *state, state->content_protection == DRM_MODE_CONTENT_PROTECTION_ENABLED) state->content_protection = DRM_MODE_CONTENT_PROTECTION_DESIRED; - /* Check if something is connected/enabled, otherwise we start hdcp but nothing is connected/enabled - * hot-plug, headless s3, dpms + /* Stream removed and re-enabled + * + * Can sometimes overlap with the HPD case, + * thus set update_hdcp to false to avoid + * setting HDCP multiple times. + * + * Handles: DESIRED -> DESIRED (Special case) + */ + if (!(old_state->crtc && old_state->crtc->enabled) && + state->crtc && state->crtc->enabled && + connector->state->content_protection == DRM_MODE_CONTENT_PROTECTION_DESIRED) { + dm_con_state->update_hdcp = false; + return true; + } + + /* Hot-plug, headless s3, dpms + * + * Only start HDCP if the display is connected/enabled. + * update_hdcp flag will be set to false until the next + * HPD comes in. * * Handles: DESIRED -> DESIRED (Special case) */