diff options
Diffstat (limited to 'drivers/gpu/drm/drm_atomic_helper.c')
| -rw-r--r-- | drivers/gpu/drm/drm_atomic_helper.c | 73 |
1 files changed, 48 insertions, 25 deletions
diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c index b191d39c071d..bcc9ca240638 100644 --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -419,6 +419,7 @@ mode_fixup(struct drm_atomic_state *state) for_each_new_connector_in_state(state, connector, new_conn_state, i) { const struct drm_encoder_helper_funcs *funcs; struct drm_encoder *encoder; + struct drm_bridge *bridge; WARN_ON(!!new_conn_state->best_encoder != !!new_conn_state->crtc); @@ -435,8 +436,10 @@ mode_fixup(struct drm_atomic_state *state) encoder = new_conn_state->best_encoder; funcs = encoder->helper_private; - ret = drm_bridge_mode_fixup(encoder->bridge, &new_crtc_state->mode, - &new_crtc_state->adjusted_mode); + bridge = drm_bridge_chain_get_first_bridge(encoder); + ret = drm_bridge_chain_mode_fixup(bridge, + &new_crtc_state->mode, + &new_crtc_state->adjusted_mode); if (!ret) { DRM_DEBUG_ATOMIC("Bridge fixup failed\n"); return -EINVAL; @@ -492,6 +495,7 @@ static enum drm_mode_status mode_valid_path(struct drm_connector *connector, struct drm_crtc *crtc, const struct drm_display_mode *mode) { + struct drm_bridge *bridge; enum drm_mode_status ret; ret = drm_encoder_mode_valid(encoder, mode); @@ -501,7 +505,8 @@ static enum drm_mode_status mode_valid_path(struct drm_connector *connector, return ret; } - ret = drm_bridge_mode_valid(encoder->bridge, mode); + bridge = drm_bridge_chain_get_first_bridge(encoder); + ret = drm_bridge_chain_mode_valid(bridge, mode); if (ret != MODE_OK) { DRM_DEBUG_ATOMIC("[BRIDGE] mode_valid() failed\n"); return ret; @@ -984,6 +989,7 @@ disable_outputs(struct drm_device *dev, struct drm_atomic_state *old_state) for_each_oldnew_connector_in_state(old_state, connector, old_conn_state, new_conn_state, i) { const struct drm_encoder_helper_funcs *funcs; struct drm_encoder *encoder; + struct drm_bridge *bridge; /* Shut down everything that's in the changeset and currently * still on. So need to check the old, saved state. */ @@ -1020,7 +1026,8 @@ disable_outputs(struct drm_device *dev, struct drm_atomic_state *old_state) * Each encoder has at most one connector (since we always steal * it away), so we won't call disable hooks twice. */ - drm_atomic_bridge_disable(encoder->bridge, old_state); + bridge = drm_bridge_chain_get_first_bridge(encoder); + drm_atomic_bridge_chain_disable(bridge, old_state); /* Right function depends upon target state. */ if (funcs) { @@ -1034,7 +1041,7 @@ disable_outputs(struct drm_device *dev, struct drm_atomic_state *old_state) funcs->dpms(encoder, DRM_MODE_DPMS_OFF); } - drm_atomic_bridge_post_disable(encoder->bridge, old_state); + drm_atomic_bridge_chain_post_disable(bridge, old_state); } for_each_oldnew_crtc_in_state(old_state, crtc, old_crtc_state, new_crtc_state, i) { @@ -1188,6 +1195,7 @@ crtc_set_mode(struct drm_device *dev, struct drm_atomic_state *old_state) const struct drm_encoder_helper_funcs *funcs; struct drm_encoder *encoder; struct drm_display_mode *mode, *adjusted_mode; + struct drm_bridge *bridge; if (!new_conn_state->best_encoder) continue; @@ -1215,7 +1223,8 @@ crtc_set_mode(struct drm_device *dev, struct drm_atomic_state *old_state) funcs->mode_set(encoder, mode, adjusted_mode); } - drm_bridge_mode_set(encoder->bridge, mode, adjusted_mode); + bridge = drm_bridge_chain_get_first_bridge(encoder); + drm_bridge_chain_mode_set(bridge, mode, adjusted_mode); } } @@ -1314,6 +1323,7 @@ void drm_atomic_helper_commit_modeset_enables(struct drm_device *dev, for_each_new_connector_in_state(old_state, connector, new_conn_state, i) { const struct drm_encoder_helper_funcs *funcs; struct drm_encoder *encoder; + struct drm_bridge *bridge; if (!new_conn_state->best_encoder) continue; @@ -1332,7 +1342,8 @@ void drm_atomic_helper_commit_modeset_enables(struct drm_device *dev, * Each encoder has at most one connector (since we always steal * it away), so we won't call enable hooks twice. */ - drm_atomic_bridge_pre_enable(encoder->bridge, old_state); + bridge = drm_bridge_chain_get_first_bridge(encoder); + drm_atomic_bridge_chain_pre_enable(bridge, old_state); if (funcs) { if (funcs->atomic_enable) @@ -1343,7 +1354,7 @@ void drm_atomic_helper_commit_modeset_enables(struct drm_device *dev, funcs->commit(encoder); } - drm_atomic_bridge_enable(encoder->bridge, old_state); + drm_atomic_bridge_chain_enable(bridge, old_state); } drm_atomic_helper_commit_writebacks(dev, old_state); @@ -1834,17 +1845,21 @@ EXPORT_SYMBOL(drm_atomic_helper_commit); /** * DOC: implementing nonblocking commit * - * Nonblocking atomic commits have to be implemented in the following sequence: + * Nonblocking atomic commits should use struct &drm_crtc_commit to sequence + * different operations against each another. Locks, especially struct + * &drm_modeset_lock, should not be held in worker threads or any other + * asynchronous context used to commit the hardware state. + * + * drm_atomic_helper_commit() implements the recommended sequence for + * nonblocking commits, using drm_atomic_helper_setup_commit() internally: * - * 1. Run drm_atomic_helper_prepare_planes() first. This is the only function - * which commit needs to call which can fail, so we want to run it first and + * 1. Run drm_atomic_helper_prepare_planes(). Since this can fail and we + * need to propagate out of memory/VRAM errors to userspace, it must be called * synchronously. * * 2. Synchronize with any outstanding nonblocking commit worker threads which - * might be affected the new state update. This can be done by either cancelling - * or flushing the work items, depending upon whether the driver can deal with - * cancelled updates. Note that it is important to ensure that the framebuffer - * cleanup is still done when cancelling. + * might be affected by the new state update. This is handled by + * drm_atomic_helper_setup_commit(). * * Asynchronous workers need to have sufficient parallelism to be able to run * different atomic commits on different CRTCs in parallel. The simplest way to @@ -1855,21 +1870,29 @@ EXPORT_SYMBOL(drm_atomic_helper_commit); * must be done as one global operation, and enabling or disabling a CRTC can * take a long time. But even that is not required. * + * IMPORTANT: A &drm_atomic_state update for multiple CRTCs is sequenced + * against all CRTCs therein. Therefore for atomic state updates which only flip + * planes the driver must not get the struct &drm_crtc_state of unrelated CRTCs + * in its atomic check code: This would prevent committing of atomic updates to + * multiple CRTCs in parallel. In general, adding additional state structures + * should be avoided as much as possible, because this reduces parallelism in + * (nonblocking) commits, both due to locking and due to commit sequencing + * requirements. + * * 3. The software state is updated synchronously with * drm_atomic_helper_swap_state(). Doing this under the protection of all modeset - * locks means concurrent callers never see inconsistent state. And doing this - * while it's guaranteed that no relevant nonblocking worker runs means that - * nonblocking workers do not need grab any locks. Actually they must not grab - * locks, for otherwise the work flushing will deadlock. + * locks means concurrent callers never see inconsistent state. Note that commit + * workers do not hold any locks; their access is only coordinated through + * ordering. If workers would access state only through the pointers in the + * free-standing state objects (currently not the case for any driver) then even + * multiple pending commits could be in-flight at the same time. * * 4. Schedule a work item to do all subsequent steps, using the split-out * commit helpers: a) pre-plane commit b) plane commit c) post-plane commit and * then cleaning up the framebuffers after the old framebuffer is no longer - * being displayed. - * - * The above scheme is implemented in the atomic helper libraries in - * drm_atomic_helper_commit() using a bunch of helper functions. See - * drm_atomic_helper_setup_commit() for a starting point. + * being displayed. The scheduled work should synchronize against other workers + * using the &drm_crtc_commit infrastructure as needed. See + * drm_atomic_helper_setup_commit() for more details. */ static int stall_checks(struct drm_crtc *crtc, bool nonblock) @@ -2098,7 +2121,7 @@ EXPORT_SYMBOL(drm_atomic_helper_setup_commit); * * This function waits for all preceeding commits that touch the same CRTC as * @old_state to both be committed to the hardware (as signalled by - * drm_atomic_helper_commit_hw_done) and executed by the hardware (as signalled + * drm_atomic_helper_commit_hw_done()) and executed by the hardware (as signalled * by calling drm_crtc_send_vblank_event() on the &drm_crtc_state.event). * * This is part of the atomic helper support for nonblocking commits, see |