From 0380c6846a4be705b2d5c964b01ba1e5aaa3f5df Mon Sep 17 00:00:00 2001 From: Daniel Vetter Date: Wed, 4 Dec 2019 11:00:11 +0100 Subject: drm/atomic: Update docs around locking and commit sequencing Both locking and especially sequencing of nonblocking commits have evolved a lot. The details are all there, but I noticed that the big picture and connections have fallen behind a bit. Apply polish. Motivated by some review discussions with Thierry. v2: Review from Thierry Reviewed-by: Thierry Reding Cc: Thierry Reding Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20191204100011.859468-1-daniel.vetter@ffwll.ch --- include/drm/drm_atomic.h | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/drm/drm_atomic.h b/include/drm/drm_atomic.h index b6c73fd9f55a..5923819dcd68 100644 --- a/include/drm/drm_atomic.h +++ b/include/drm/drm_atomic.h @@ -60,8 +60,8 @@ * wait for flip_done <---- * clean up atomic state * - * The important bit to know is that cleanup_done is the terminal event, but the - * ordering between flip_done and hw_done is entirely up to the specific driver + * The important bit to know is that &cleanup_done is the terminal event, but the + * ordering between &flip_done and &hw_done is entirely up to the specific driver * and modeset state change. * * For an implementation of how to use this look at @@ -92,6 +92,9 @@ struct drm_crtc_commit { * commit is sent to userspace, or when an out-fence is singalled. Note * that for most hardware, in most cases this happens after @hw_done is * signalled. + * + * Completion of this stage is signalled implicitly by calling + * drm_crtc_send_vblank_event() on &drm_crtc_state.event. */ struct completion flip_done; @@ -107,6 +110,9 @@ struct drm_crtc_commit { * Note that this does not need to include separately reference-counted * resources like backing storage buffer pinning, or runtime pm * management. + * + * Drivers should call drm_atomic_helper_commit_hw_done() to signal + * completion of this stage. */ struct completion hw_done; @@ -118,6 +124,9 @@ struct drm_crtc_commit { * a vblank wait completed it might be a bit later. This completion is * useful to throttle updates and avoid hardware updates getting ahead * of the buffer cleanup too much. + * + * Drivers should call drm_atomic_helper_commit_cleanup_done() to signal + * completion of this stage. */ struct completion cleanup_done; -- cgit v1.2.3