2 * Copyright (C) 2014 Red Hat
3 * Author: Rob Clark <robdclark@gmail.com>
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 as published by
7 * the Free Software Foundation.
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
14 * You should have received a copy of the GNU General Public License along with
15 * this program. If not, see <http://www.gnu.org/licenses/>.
23 struct drm_device *dev;
24 struct drm_atomic_state *state;
26 struct msm_fence_cb fence_cb;
30 static void fence_cb(struct msm_fence_cb *cb);
32 /* block until specified crtcs are no longer pending update, and
33 * atomically mark them as pending update
35 static int start_atomic(struct msm_drm_private *priv, uint32_t crtc_mask)
39 spin_lock(&priv->pending_crtcs_event.lock);
40 ret = wait_event_interruptible_locked(priv->pending_crtcs_event,
41 !(priv->pending_crtcs & crtc_mask));
43 DBG("start: %08x", crtc_mask);
44 priv->pending_crtcs |= crtc_mask;
46 spin_unlock(&priv->pending_crtcs_event.lock);
51 /* clear specified crtcs (no longer pending update)
53 static void end_atomic(struct msm_drm_private *priv, uint32_t crtc_mask)
55 spin_lock(&priv->pending_crtcs_event.lock);
56 DBG("end: %08x", crtc_mask);
57 priv->pending_crtcs &= ~crtc_mask;
58 wake_up_all_locked(&priv->pending_crtcs_event);
59 spin_unlock(&priv->pending_crtcs_event.lock);
62 static struct msm_commit *commit_init(struct drm_atomic_state *state)
64 struct msm_commit *c = kzalloc(sizeof(*c), GFP_KERNEL);
72 /* TODO we might need a way to indicate to run the cb on a
73 * different wq so wait_for_vblanks() doesn't block retiring
76 INIT_FENCE_CB(&c->fence_cb, fence_cb);
81 static void commit_destroy(struct msm_commit *c)
83 end_atomic(c->dev->dev_private, c->crtc_mask);
87 static void msm_atomic_wait_for_commit_done(struct drm_device *dev,
88 struct drm_atomic_state *old_state)
90 struct drm_crtc *crtc;
91 struct msm_drm_private *priv = old_state->dev->dev_private;
92 struct msm_kms *kms = priv->kms;
93 int ncrtcs = old_state->dev->mode_config.num_crtc;
96 for (i = 0; i < ncrtcs; i++) {
97 crtc = old_state->crtcs[i];
102 if (!crtc->state->enable)
105 /* Legacy cursor ioctls are completely unsynced, and userspace
106 * relies on that (by doing tons of cursor updates). */
107 if (old_state->legacy_cursor_update)
110 if (drm_crtc_vblank_get(crtc))
113 kms->funcs->wait_for_crtc_commit_done(kms, crtc);
115 drm_crtc_vblank_put(crtc);
119 /* The (potentially) asynchronous part of the commit. At this point
120 * nothing can fail short of armageddon.
122 static void complete_commit(struct msm_commit *c)
124 struct drm_atomic_state *state = c->state;
125 struct drm_device *dev = state->dev;
126 struct msm_drm_private *priv = dev->dev_private;
127 struct msm_kms *kms = priv->kms;
129 kms->funcs->prepare_commit(kms, state);
131 drm_atomic_helper_commit_modeset_disables(dev, state);
133 drm_atomic_helper_commit_planes(dev, state, false);
135 drm_atomic_helper_commit_modeset_enables(dev, state);
137 /* NOTE: _wait_for_vblanks() only waits for vblank on
138 * enabled CRTCs. So we end up faulting when disabling
139 * due to (potentially) unref'ing the outgoing fb's
140 * before the vblank when the disable has latched.
142 * But if it did wait on disabled (or newly disabled)
143 * CRTCs, that would be racy (ie. we could have missed
144 * the irq. We need some way to poll for pipe shut
145 * down. Or just live with occasionally hitting the
146 * timeout in the CRTC disable path (which really should
147 * not be critical path)
150 msm_atomic_wait_for_commit_done(dev, state);
152 drm_atomic_helper_cleanup_planes(dev, state);
154 kms->funcs->complete_commit(kms, state);
156 drm_atomic_state_free(state);
161 static void fence_cb(struct msm_fence_cb *cb)
163 struct msm_commit *c =
164 container_of(cb, struct msm_commit, fence_cb);
168 static void add_fb(struct msm_commit *c, struct drm_framebuffer *fb)
170 struct drm_gem_object *obj = msm_framebuffer_bo(fb, 0);
171 c->fence = max(c->fence, msm_gem_fence(to_msm_bo(obj), MSM_PREP_READ));
174 int msm_atomic_check(struct drm_device *dev,
175 struct drm_atomic_state *state)
180 * msm ->atomic_check can update ->mode_changed for pixel format
181 * changes, hence must be run before we check the modeset changes.
183 ret = drm_atomic_helper_check_planes(dev, state);
187 ret = drm_atomic_helper_check_modeset(dev, state);
195 * drm_atomic_helper_commit - commit validated state object
197 * @state: the driver state object
198 * @async: asynchronous commit
200 * This function commits a with drm_atomic_helper_check() pre-validated state
201 * object. This can still fail when e.g. the framebuffer reservation fails. For
202 * now this doesn't implement asynchronous commits.
205 * Zero for success or -errno.
207 int msm_atomic_commit(struct drm_device *dev,
208 struct drm_atomic_state *state, bool async)
210 int nplanes = dev->mode_config.num_total_plane;
211 int ncrtcs = dev->mode_config.num_crtc;
213 struct msm_commit *c;
216 ret = drm_atomic_helper_prepare_planes(dev, state);
220 c = commit_init(state);
227 * Figure out what crtcs we have:
229 for (i = 0; i < ncrtcs; i++) {
230 struct drm_crtc *crtc = state->crtcs[i];
233 c->crtc_mask |= (1 << drm_crtc_index(crtc));
237 * Figure out what fence to wait for:
239 for (i = 0; i < nplanes; i++) {
240 struct drm_plane *plane = state->planes[i];
241 struct drm_plane_state *new_state = state->plane_states[i];
246 if ((plane->state->fb != new_state->fb) && new_state->fb)
247 add_fb(c, new_state->fb);
251 * Wait for pending updates on any of the same crtc's and then
252 * mark our set of crtc's as busy:
254 ret = start_atomic(dev->dev_private, c->crtc_mask);
261 * This is the point of no return - everything below never fails except
262 * when the hw goes bonghits. Which means we can commit the new state on
263 * the software side now.
266 drm_atomic_helper_swap_state(dev, state);
269 * Everything below can be run asynchronously without the need to grab
270 * any modeset locks at all under one conditions: It must be guaranteed
271 * that the asynchronous work has either been cancelled (if the driver
272 * supports it, which at least requires that the framebuffers get
273 * cleaned up with drm_atomic_helper_cleanup_planes()) or completed
274 * before the new state gets committed on the software side with
275 * drm_atomic_helper_swap_state().
277 * This scheme allows new atomic state updates to be prepared and
278 * checked in parallel to the asynchronous completion of the previous
279 * update. Which is important since compositors need to figure out the
280 * composition of the next frame right after having submitted the
285 msm_queue_fence_cb(dev, &c->fence_cb, c->fence);
289 timeout = ktime_add_ms(ktime_get(), 1000);
291 /* uninterruptible wait */
292 msm_wait_fence(dev, c->fence, &timeout, false);
299 drm_atomic_helper_cleanup_planes(dev, state);