Loading...
1/*
2 * Copyright (C) 2014 Red Hat
3 * Author: Rob Clark <robdclark@gmail.com>
4 *
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.
8 *
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
12 * more details.
13 *
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/>.
16 */
17
18#include "msm_drv.h"
19#include "msm_kms.h"
20#include "msm_gem.h"
21
22struct msm_commit {
23 struct drm_device *dev;
24 struct drm_atomic_state *state;
25 uint32_t fence;
26 struct msm_fence_cb fence_cb;
27 uint32_t crtc_mask;
28};
29
30static void fence_cb(struct msm_fence_cb *cb);
31
32/* block until specified crtcs are no longer pending update, and
33 * atomically mark them as pending update
34 */
35static int start_atomic(struct msm_drm_private *priv, uint32_t crtc_mask)
36{
37 int ret;
38
39 spin_lock(&priv->pending_crtcs_event.lock);
40 ret = wait_event_interruptible_locked(priv->pending_crtcs_event,
41 !(priv->pending_crtcs & crtc_mask));
42 if (ret == 0) {
43 DBG("start: %08x", crtc_mask);
44 priv->pending_crtcs |= crtc_mask;
45 }
46 spin_unlock(&priv->pending_crtcs_event.lock);
47
48 return ret;
49}
50
51/* clear specified crtcs (no longer pending update)
52 */
53static void end_atomic(struct msm_drm_private *priv, uint32_t crtc_mask)
54{
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);
60}
61
62static struct msm_commit *commit_init(struct drm_atomic_state *state)
63{
64 struct msm_commit *c = kzalloc(sizeof(*c), GFP_KERNEL);
65
66 if (!c)
67 return NULL;
68
69 c->dev = state->dev;
70 c->state = state;
71
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
74 * bo's..
75 */
76 INIT_FENCE_CB(&c->fence_cb, fence_cb);
77
78 return c;
79}
80
81static void commit_destroy(struct msm_commit *c)
82{
83 end_atomic(c->dev->dev_private, c->crtc_mask);
84 kfree(c);
85}
86
87static void msm_atomic_wait_for_commit_done(struct drm_device *dev,
88 struct drm_atomic_state *old_state)
89{
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;
94 int i;
95
96 for (i = 0; i < ncrtcs; i++) {
97 crtc = old_state->crtcs[i];
98
99 if (!crtc)
100 continue;
101
102 if (!crtc->state->enable)
103 continue;
104
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)
108 continue;
109
110 kms->funcs->wait_for_crtc_commit_done(kms, crtc);
111 }
112}
113
114/* The (potentially) asynchronous part of the commit. At this point
115 * nothing can fail short of armageddon.
116 */
117static void complete_commit(struct msm_commit *c)
118{
119 struct drm_atomic_state *state = c->state;
120 struct drm_device *dev = state->dev;
121 struct msm_drm_private *priv = dev->dev_private;
122 struct msm_kms *kms = priv->kms;
123
124 kms->funcs->prepare_commit(kms, state);
125
126 drm_atomic_helper_commit_modeset_disables(dev, state);
127
128 drm_atomic_helper_commit_planes(dev, state, false);
129
130 drm_atomic_helper_commit_modeset_enables(dev, state);
131
132 /* NOTE: _wait_for_vblanks() only waits for vblank on
133 * enabled CRTCs. So we end up faulting when disabling
134 * due to (potentially) unref'ing the outgoing fb's
135 * before the vblank when the disable has latched.
136 *
137 * But if it did wait on disabled (or newly disabled)
138 * CRTCs, that would be racy (ie. we could have missed
139 * the irq. We need some way to poll for pipe shut
140 * down. Or just live with occasionally hitting the
141 * timeout in the CRTC disable path (which really should
142 * not be critical path)
143 */
144
145 msm_atomic_wait_for_commit_done(dev, state);
146
147 drm_atomic_helper_cleanup_planes(dev, state);
148
149 kms->funcs->complete_commit(kms, state);
150
151 drm_atomic_state_free(state);
152
153 commit_destroy(c);
154}
155
156static void fence_cb(struct msm_fence_cb *cb)
157{
158 struct msm_commit *c =
159 container_of(cb, struct msm_commit, fence_cb);
160 complete_commit(c);
161}
162
163static void add_fb(struct msm_commit *c, struct drm_framebuffer *fb)
164{
165 struct drm_gem_object *obj = msm_framebuffer_bo(fb, 0);
166 c->fence = max(c->fence, msm_gem_fence(to_msm_bo(obj), MSM_PREP_READ));
167}
168
169int msm_atomic_check(struct drm_device *dev,
170 struct drm_atomic_state *state)
171{
172 int ret;
173
174 /*
175 * msm ->atomic_check can update ->mode_changed for pixel format
176 * changes, hence must be run before we check the modeset changes.
177 */
178 ret = drm_atomic_helper_check_planes(dev, state);
179 if (ret)
180 return ret;
181
182 ret = drm_atomic_helper_check_modeset(dev, state);
183 if (ret)
184 return ret;
185
186 return ret;
187}
188
189/**
190 * drm_atomic_helper_commit - commit validated state object
191 * @dev: DRM device
192 * @state: the driver state object
193 * @async: asynchronous commit
194 *
195 * This function commits a with drm_atomic_helper_check() pre-validated state
196 * object. This can still fail when e.g. the framebuffer reservation fails. For
197 * now this doesn't implement asynchronous commits.
198 *
199 * RETURNS
200 * Zero for success or -errno.
201 */
202int msm_atomic_commit(struct drm_device *dev,
203 struct drm_atomic_state *state, bool async)
204{
205 int nplanes = dev->mode_config.num_total_plane;
206 int ncrtcs = dev->mode_config.num_crtc;
207 ktime_t timeout;
208 struct msm_commit *c;
209 int i, ret;
210
211 ret = drm_atomic_helper_prepare_planes(dev, state);
212 if (ret)
213 return ret;
214
215 c = commit_init(state);
216 if (!c) {
217 ret = -ENOMEM;
218 goto error;
219 }
220
221 /*
222 * Figure out what crtcs we have:
223 */
224 for (i = 0; i < ncrtcs; i++) {
225 struct drm_crtc *crtc = state->crtcs[i];
226 if (!crtc)
227 continue;
228 c->crtc_mask |= (1 << drm_crtc_index(crtc));
229 }
230
231 /*
232 * Figure out what fence to wait for:
233 */
234 for (i = 0; i < nplanes; i++) {
235 struct drm_plane *plane = state->planes[i];
236 struct drm_plane_state *new_state = state->plane_states[i];
237
238 if (!plane)
239 continue;
240
241 if ((plane->state->fb != new_state->fb) && new_state->fb)
242 add_fb(c, new_state->fb);
243 }
244
245 /*
246 * Wait for pending updates on any of the same crtc's and then
247 * mark our set of crtc's as busy:
248 */
249 ret = start_atomic(dev->dev_private, c->crtc_mask);
250 if (ret) {
251 kfree(c);
252 goto error;
253 }
254
255 /*
256 * This is the point of no return - everything below never fails except
257 * when the hw goes bonghits. Which means we can commit the new state on
258 * the software side now.
259 */
260
261 drm_atomic_helper_swap_state(dev, state);
262
263 /*
264 * Everything below can be run asynchronously without the need to grab
265 * any modeset locks at all under one conditions: It must be guaranteed
266 * that the asynchronous work has either been cancelled (if the driver
267 * supports it, which at least requires that the framebuffers get
268 * cleaned up with drm_atomic_helper_cleanup_planes()) or completed
269 * before the new state gets committed on the software side with
270 * drm_atomic_helper_swap_state().
271 *
272 * This scheme allows new atomic state updates to be prepared and
273 * checked in parallel to the asynchronous completion of the previous
274 * update. Which is important since compositors need to figure out the
275 * composition of the next frame right after having submitted the
276 * current layout.
277 */
278
279 if (async) {
280 msm_queue_fence_cb(dev, &c->fence_cb, c->fence);
281 return 0;
282 }
283
284 timeout = ktime_add_ms(ktime_get(), 1000);
285
286 /* uninterruptible wait */
287 msm_wait_fence(dev, c->fence, &timeout, false);
288
289 complete_commit(c);
290
291 return 0;
292
293error:
294 drm_atomic_helper_cleanup_planes(dev, state);
295 return ret;
296}
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2014 Red Hat
4 * Author: Rob Clark <robdclark@gmail.com>
5 */
6
7#include <drm/drm_atomic_uapi.h>
8#include <drm/drm_vblank.h>
9
10#include "msm_atomic_trace.h"
11#include "msm_drv.h"
12#include "msm_gem.h"
13#include "msm_kms.h"
14
15/*
16 * Helpers to control vblanks while we flush.. basically just to ensure
17 * that vblank accounting is switched on, so we get valid seqn/timestamp
18 * on pageflip events (if requested)
19 */
20
21static void vblank_get(struct msm_kms *kms, unsigned crtc_mask)
22{
23 struct drm_crtc *crtc;
24
25 for_each_crtc_mask(kms->dev, crtc, crtc_mask) {
26 if (!crtc->state->active)
27 continue;
28 drm_crtc_vblank_get(crtc);
29 }
30}
31
32static void vblank_put(struct msm_kms *kms, unsigned crtc_mask)
33{
34 struct drm_crtc *crtc;
35
36 for_each_crtc_mask(kms->dev, crtc, crtc_mask) {
37 if (!crtc->state->active)
38 continue;
39 drm_crtc_vblank_put(crtc);
40 }
41}
42
43static void lock_crtcs(struct msm_kms *kms, unsigned int crtc_mask)
44{
45 int crtc_index;
46 struct drm_crtc *crtc;
47
48 for_each_crtc_mask(kms->dev, crtc, crtc_mask) {
49 crtc_index = drm_crtc_index(crtc);
50 mutex_lock_nested(&kms->commit_lock[crtc_index], crtc_index);
51 }
52}
53
54static void unlock_crtcs(struct msm_kms *kms, unsigned int crtc_mask)
55{
56 struct drm_crtc *crtc;
57
58 for_each_crtc_mask_reverse(kms->dev, crtc, crtc_mask)
59 mutex_unlock(&kms->commit_lock[drm_crtc_index(crtc)]);
60}
61
62static void msm_atomic_async_commit(struct msm_kms *kms, int crtc_idx)
63{
64 unsigned crtc_mask = BIT(crtc_idx);
65
66 trace_msm_atomic_async_commit_start(crtc_mask);
67
68 lock_crtcs(kms, crtc_mask);
69
70 if (!(kms->pending_crtc_mask & crtc_mask)) {
71 unlock_crtcs(kms, crtc_mask);
72 goto out;
73 }
74
75 kms->pending_crtc_mask &= ~crtc_mask;
76
77 kms->funcs->enable_commit(kms);
78
79 vblank_get(kms, crtc_mask);
80
81 /*
82 * Flush hardware updates:
83 */
84 trace_msm_atomic_flush_commit(crtc_mask);
85 kms->funcs->flush_commit(kms, crtc_mask);
86
87 /*
88 * Wait for flush to complete:
89 */
90 trace_msm_atomic_wait_flush_start(crtc_mask);
91 kms->funcs->wait_flush(kms, crtc_mask);
92 trace_msm_atomic_wait_flush_finish(crtc_mask);
93
94 vblank_put(kms, crtc_mask);
95
96 kms->funcs->complete_commit(kms, crtc_mask);
97 unlock_crtcs(kms, crtc_mask);
98 kms->funcs->disable_commit(kms);
99
100out:
101 trace_msm_atomic_async_commit_finish(crtc_mask);
102}
103
104static void msm_atomic_pending_work(struct kthread_work *work)
105{
106 struct msm_pending_timer *timer = container_of(work,
107 struct msm_pending_timer, work.work);
108
109 msm_atomic_async_commit(timer->kms, timer->crtc_idx);
110}
111
112int msm_atomic_init_pending_timer(struct msm_pending_timer *timer,
113 struct msm_kms *kms, int crtc_idx)
114{
115 timer->kms = kms;
116 timer->crtc_idx = crtc_idx;
117
118 timer->worker = kthread_create_worker(0, "atomic-worker-%d", crtc_idx);
119 if (IS_ERR(timer->worker)) {
120 int ret = PTR_ERR(timer->worker);
121 timer->worker = NULL;
122 return ret;
123 }
124 sched_set_fifo(timer->worker->task);
125
126 msm_hrtimer_work_init(&timer->work, timer->worker,
127 msm_atomic_pending_work,
128 CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
129
130 return 0;
131}
132
133void msm_atomic_destroy_pending_timer(struct msm_pending_timer *timer)
134{
135 if (timer->worker)
136 kthread_destroy_worker(timer->worker);
137}
138
139static bool can_do_async(struct drm_atomic_state *state,
140 struct drm_crtc **async_crtc)
141{
142 struct drm_connector_state *connector_state;
143 struct drm_connector *connector;
144 struct drm_crtc_state *crtc_state;
145 struct drm_crtc *crtc;
146 int i, num_crtcs = 0;
147
148 if (!(state->legacy_cursor_update || state->async_update))
149 return false;
150
151 /* any connector change, means slow path: */
152 for_each_new_connector_in_state(state, connector, connector_state, i)
153 return false;
154
155 for_each_new_crtc_in_state(state, crtc, crtc_state, i) {
156 if (drm_atomic_crtc_needs_modeset(crtc_state))
157 return false;
158 if (++num_crtcs > 1)
159 return false;
160 *async_crtc = crtc;
161 }
162
163 return true;
164}
165
166/* Get bitmask of crtcs that will need to be flushed. The bitmask
167 * can be used with for_each_crtc_mask() iterator, to iterate
168 * effected crtcs without needing to preserve the atomic state.
169 */
170static unsigned get_crtc_mask(struct drm_atomic_state *state)
171{
172 struct drm_crtc_state *crtc_state;
173 struct drm_crtc *crtc;
174 unsigned i, mask = 0;
175
176 for_each_new_crtc_in_state(state, crtc, crtc_state, i)
177 mask |= drm_crtc_mask(crtc);
178
179 return mask;
180}
181
182void msm_atomic_commit_tail(struct drm_atomic_state *state)
183{
184 struct drm_device *dev = state->dev;
185 struct msm_drm_private *priv = dev->dev_private;
186 struct msm_kms *kms = priv->kms;
187 struct drm_crtc *async_crtc = NULL;
188 unsigned crtc_mask = get_crtc_mask(state);
189 bool async = kms->funcs->vsync_time &&
190 can_do_async(state, &async_crtc);
191
192 trace_msm_atomic_commit_tail_start(async, crtc_mask);
193
194 kms->funcs->enable_commit(kms);
195
196 /*
197 * Ensure any previous (potentially async) commit has
198 * completed:
199 */
200 lock_crtcs(kms, crtc_mask);
201 trace_msm_atomic_wait_flush_start(crtc_mask);
202 kms->funcs->wait_flush(kms, crtc_mask);
203 trace_msm_atomic_wait_flush_finish(crtc_mask);
204
205 /*
206 * Now that there is no in-progress flush, prepare the
207 * current update:
208 */
209 kms->funcs->prepare_commit(kms, state);
210
211 /*
212 * Push atomic updates down to hardware:
213 */
214 drm_atomic_helper_commit_modeset_disables(dev, state);
215 drm_atomic_helper_commit_planes(dev, state, 0);
216 drm_atomic_helper_commit_modeset_enables(dev, state);
217
218 if (async) {
219 struct msm_pending_timer *timer =
220 &kms->pending_timers[drm_crtc_index(async_crtc)];
221
222 /* async updates are limited to single-crtc updates: */
223 WARN_ON(crtc_mask != drm_crtc_mask(async_crtc));
224
225 /*
226 * Start timer if we don't already have an update pending
227 * on this crtc:
228 */
229 if (!(kms->pending_crtc_mask & crtc_mask)) {
230 ktime_t vsync_time, wakeup_time;
231
232 kms->pending_crtc_mask |= crtc_mask;
233
234 vsync_time = kms->funcs->vsync_time(kms, async_crtc);
235 wakeup_time = ktime_sub(vsync_time, ms_to_ktime(1));
236
237 msm_hrtimer_queue_work(&timer->work, wakeup_time,
238 HRTIMER_MODE_ABS);
239 }
240
241 kms->funcs->disable_commit(kms);
242 unlock_crtcs(kms, crtc_mask);
243 /*
244 * At this point, from drm core's perspective, we
245 * are done with the atomic update, so we can just
246 * go ahead and signal that it is done:
247 */
248 drm_atomic_helper_commit_hw_done(state);
249 drm_atomic_helper_cleanup_planes(dev, state);
250
251 trace_msm_atomic_commit_tail_finish(async, crtc_mask);
252
253 return;
254 }
255
256 /*
257 * If there is any async flush pending on updated crtcs, fold
258 * them into the current flush.
259 */
260 kms->pending_crtc_mask &= ~crtc_mask;
261
262 vblank_get(kms, crtc_mask);
263
264 /*
265 * Flush hardware updates:
266 */
267 trace_msm_atomic_flush_commit(crtc_mask);
268 kms->funcs->flush_commit(kms, crtc_mask);
269 unlock_crtcs(kms, crtc_mask);
270 /*
271 * Wait for flush to complete:
272 */
273 trace_msm_atomic_wait_flush_start(crtc_mask);
274 kms->funcs->wait_flush(kms, crtc_mask);
275 trace_msm_atomic_wait_flush_finish(crtc_mask);
276
277 vblank_put(kms, crtc_mask);
278
279 lock_crtcs(kms, crtc_mask);
280 kms->funcs->complete_commit(kms, crtc_mask);
281 unlock_crtcs(kms, crtc_mask);
282 kms->funcs->disable_commit(kms);
283
284 drm_atomic_helper_commit_hw_done(state);
285 drm_atomic_helper_cleanup_planes(dev, state);
286
287 trace_msm_atomic_commit_tail_finish(async, crtc_mask);
288}