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/>.
21 #include "msm_fence.h"
24 struct drm_device *dev;
25 struct drm_atomic_state *state;
26 struct work_struct work;
30 static void commit_worker(struct work_struct *work);
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 INIT_WORK(&c->work, commit_worker);
77 static void commit_destroy(struct msm_commit *c)
79 end_atomic(c->dev->dev_private, c->crtc_mask);
83 static void msm_atomic_wait_for_commit_done(struct drm_device *dev,
84 struct drm_atomic_state *old_state)
86 struct drm_crtc *crtc;
87 struct drm_crtc_state *crtc_state;
88 struct msm_drm_private *priv = old_state->dev->dev_private;
89 struct msm_kms *kms = priv->kms;
92 for_each_crtc_in_state(old_state, crtc, crtc_state, i) {
93 if (!crtc->state->enable)
96 /* Legacy cursor ioctls are completely unsynced, and userspace
97 * relies on that (by doing tons of cursor updates). */
98 if (old_state->legacy_cursor_update)
101 if (drm_crtc_vblank_get(crtc))
104 kms->funcs->wait_for_crtc_commit_done(kms, crtc);
106 drm_crtc_vblank_put(crtc);
110 /* The (potentially) asynchronous part of the commit. At this point
111 * nothing can fail short of armageddon.
113 static void complete_commit(struct msm_commit *c, bool async)
115 struct drm_atomic_state *state = c->state;
116 struct drm_device *dev = state->dev;
117 struct msm_drm_private *priv = dev->dev_private;
118 struct msm_kms *kms = priv->kms;
120 drm_atomic_helper_wait_for_fences(dev, state, false);
122 kms->funcs->prepare_commit(kms, state);
124 drm_atomic_helper_commit_modeset_disables(dev, state);
126 drm_atomic_helper_commit_planes(dev, state, 0);
128 drm_atomic_helper_commit_modeset_enables(dev, state);
130 /* NOTE: _wait_for_vblanks() only waits for vblank on
131 * enabled CRTCs. So we end up faulting when disabling
132 * due to (potentially) unref'ing the outgoing fb's
133 * before the vblank when the disable has latched.
135 * But if it did wait on disabled (or newly disabled)
136 * CRTCs, that would be racy (ie. we could have missed
137 * the irq. We need some way to poll for pipe shut
138 * down. Or just live with occasionally hitting the
139 * timeout in the CRTC disable path (which really should
140 * not be critical path)
143 msm_atomic_wait_for_commit_done(dev, state);
145 drm_atomic_helper_cleanup_planes(dev, state);
147 kms->funcs->complete_commit(kms, state);
149 drm_atomic_state_free(state);
154 static void commit_worker(struct work_struct *work)
156 complete_commit(container_of(work, struct msm_commit, work), true);
159 int msm_atomic_check(struct drm_device *dev,
160 struct drm_atomic_state *state)
165 * msm ->atomic_check can update ->mode_changed for pixel format
166 * changes, hence must be run before we check the modeset changes.
168 ret = drm_atomic_helper_check_planes(dev, state);
172 ret = drm_atomic_helper_check_modeset(dev, state);
180 * drm_atomic_helper_commit - commit validated state object
182 * @state: the driver state object
183 * @nonblock: nonblocking commit
185 * This function commits a with drm_atomic_helper_check() pre-validated state
186 * object. This can still fail when e.g. the framebuffer reservation fails.
189 * Zero for success or -errno.
191 int msm_atomic_commit(struct drm_device *dev,
192 struct drm_atomic_state *state, bool nonblock)
194 struct msm_drm_private *priv = dev->dev_private;
195 struct msm_commit *c;
196 struct drm_crtc *crtc;
197 struct drm_crtc_state *crtc_state;
198 struct drm_plane *plane;
199 struct drm_plane_state *plane_state;
202 ret = drm_atomic_helper_prepare_planes(dev, state);
206 c = commit_init(state);
213 * Figure out what crtcs we have:
215 for_each_crtc_in_state(state, crtc, crtc_state, i)
216 c->crtc_mask |= drm_crtc_mask(crtc);
219 * Figure out what fence to wait for:
221 for_each_plane_in_state(state, plane, plane_state, i) {
222 if ((plane->state->fb != plane_state->fb) && plane_state->fb) {
223 struct drm_gem_object *obj = msm_framebuffer_bo(plane_state->fb, 0);
224 struct msm_gem_object *msm_obj = to_msm_bo(obj);
226 plane_state->fence = reservation_object_get_excl_rcu(msm_obj->resv);
231 * Wait for pending updates on any of the same crtc's and then
232 * mark our set of crtc's as busy:
234 ret = start_atomic(dev->dev_private, c->crtc_mask);
241 * This is the point of no return - everything below never fails except
242 * when the hw goes bonghits. Which means we can commit the new state on
243 * the software side now.
246 drm_atomic_helper_swap_state(state, true);
249 * Everything below can be run asynchronously without the need to grab
250 * any modeset locks at all under one conditions: It must be guaranteed
251 * that the asynchronous work has either been cancelled (if the driver
252 * supports it, which at least requires that the framebuffers get
253 * cleaned up with drm_atomic_helper_cleanup_planes()) or completed
254 * before the new state gets committed on the software side with
255 * drm_atomic_helper_swap_state().
257 * This scheme allows new atomic state updates to be prepared and
258 * checked in parallel to the asynchronous completion of the previous
259 * update. Which is important since compositors need to figure out the
260 * composition of the next frame right after having submitted the
265 queue_work(priv->atomic_wq, &c->work);
269 complete_commit(c, false);
274 drm_atomic_helper_cleanup_planes(dev, state);