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  
vblank_get(struct msm_kms * kms,unsigned crtc_mask)21  static 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  
vblank_put(struct msm_kms * kms,unsigned crtc_mask)32  static 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  
lock_crtcs(struct msm_kms * kms,unsigned int crtc_mask)43  static 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  
unlock_crtcs(struct msm_kms * kms,unsigned int crtc_mask)54  static 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  
msm_atomic_async_commit(struct msm_kms * kms,int crtc_idx)62  static 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  
100  out:
101  	trace_msm_atomic_async_commit_finish(crtc_mask);
102  }
103  
msm_atomic_pending_work(struct kthread_work * work)104  static 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  
msm_atomic_init_pending_timer(struct msm_pending_timer * timer,struct msm_kms * kms,int crtc_idx)112  int 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  
msm_atomic_destroy_pending_timer(struct msm_pending_timer * timer)133  void msm_atomic_destroy_pending_timer(struct msm_pending_timer *timer)
134  {
135  	if (timer->worker)
136  		kthread_destroy_worker(timer->worker);
137  }
138  
can_do_async(struct drm_atomic_state * state,struct drm_crtc ** async_crtc)139  static 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 (!crtc_state->active)
159  			return false;
160  		if (++num_crtcs > 1)
161  			return false;
162  		*async_crtc = crtc;
163  	}
164  
165  	return true;
166  }
167  
168  /* Get bitmask of crtcs that will need to be flushed.  The bitmask
169   * can be used with for_each_crtc_mask() iterator, to iterate
170   * effected crtcs without needing to preserve the atomic state.
171   */
get_crtc_mask(struct drm_atomic_state * state)172  static unsigned get_crtc_mask(struct drm_atomic_state *state)
173  {
174  	struct drm_crtc_state *crtc_state;
175  	struct drm_crtc *crtc;
176  	unsigned i, mask = 0;
177  
178  	for_each_new_crtc_in_state(state, crtc, crtc_state, i)
179  		mask |= drm_crtc_mask(crtc);
180  
181  	return mask;
182  }
183  
msm_atomic_check(struct drm_device * dev,struct drm_atomic_state * state)184  int msm_atomic_check(struct drm_device *dev, struct drm_atomic_state *state)
185  {
186  	struct drm_crtc_state *old_crtc_state, *new_crtc_state;
187  	struct drm_crtc *crtc;
188  	int i;
189  
190  	for_each_oldnew_crtc_in_state(state, crtc, old_crtc_state,
191  				      new_crtc_state, i) {
192  		if ((old_crtc_state->ctm && !new_crtc_state->ctm) ||
193  		    (!old_crtc_state->ctm && new_crtc_state->ctm)) {
194  			new_crtc_state->mode_changed = true;
195  			state->allow_modeset = true;
196  		}
197  	}
198  
199  	return drm_atomic_helper_check(dev, state);
200  }
201  
msm_atomic_commit_tail(struct drm_atomic_state * state)202  void msm_atomic_commit_tail(struct drm_atomic_state *state)
203  {
204  	struct drm_device *dev = state->dev;
205  	struct msm_drm_private *priv = dev->dev_private;
206  	struct msm_kms *kms = priv->kms;
207  	struct drm_crtc *async_crtc = NULL;
208  	unsigned crtc_mask = get_crtc_mask(state);
209  	bool async = can_do_async(state, &async_crtc);
210  
211  	trace_msm_atomic_commit_tail_start(async, crtc_mask);
212  
213  	kms->funcs->enable_commit(kms);
214  
215  	/*
216  	 * Ensure any previous (potentially async) commit has
217  	 * completed:
218  	 */
219  	lock_crtcs(kms, crtc_mask);
220  	trace_msm_atomic_wait_flush_start(crtc_mask);
221  	kms->funcs->wait_flush(kms, crtc_mask);
222  	trace_msm_atomic_wait_flush_finish(crtc_mask);
223  
224  	/*
225  	 * Now that there is no in-progress flush, prepare the
226  	 * current update:
227  	 */
228  	if (kms->funcs->prepare_commit)
229  		kms->funcs->prepare_commit(kms, state);
230  
231  	/*
232  	 * Push atomic updates down to hardware:
233  	 */
234  	drm_atomic_helper_commit_modeset_disables(dev, state);
235  	drm_atomic_helper_commit_planes(dev, state, 0);
236  	drm_atomic_helper_commit_modeset_enables(dev, state);
237  
238  	if (async) {
239  		struct msm_pending_timer *timer =
240  			&kms->pending_timers[drm_crtc_index(async_crtc)];
241  
242  		/* async updates are limited to single-crtc updates: */
243  		WARN_ON(crtc_mask != drm_crtc_mask(async_crtc));
244  
245  		/*
246  		 * Start timer if we don't already have an update pending
247  		 * on this crtc:
248  		 */
249  		if (!(kms->pending_crtc_mask & crtc_mask)) {
250  			ktime_t vsync_time, wakeup_time;
251  
252  			kms->pending_crtc_mask |= crtc_mask;
253  
254  			if (drm_crtc_next_vblank_start(async_crtc, &vsync_time))
255  				goto fallback;
256  
257  			wakeup_time = ktime_sub(vsync_time, ms_to_ktime(1));
258  
259  			msm_hrtimer_queue_work(&timer->work, wakeup_time,
260  					HRTIMER_MODE_ABS);
261  		}
262  
263  		kms->funcs->disable_commit(kms);
264  		unlock_crtcs(kms, crtc_mask);
265  		/*
266  		 * At this point, from drm core's perspective, we
267  		 * are done with the atomic update, so we can just
268  		 * go ahead and signal that it is done:
269  		 */
270  		drm_atomic_helper_commit_hw_done(state);
271  		drm_atomic_helper_cleanup_planes(dev, state);
272  
273  		trace_msm_atomic_commit_tail_finish(async, crtc_mask);
274  
275  		return;
276  	}
277  
278  fallback:
279  	/*
280  	 * If there is any async flush pending on updated crtcs, fold
281  	 * them into the current flush.
282  	 */
283  	kms->pending_crtc_mask &= ~crtc_mask;
284  
285  	vblank_get(kms, crtc_mask);
286  
287  	/*
288  	 * Flush hardware updates:
289  	 */
290  	trace_msm_atomic_flush_commit(crtc_mask);
291  	kms->funcs->flush_commit(kms, crtc_mask);
292  	unlock_crtcs(kms, crtc_mask);
293  	/*
294  	 * Wait for flush to complete:
295  	 */
296  	trace_msm_atomic_wait_flush_start(crtc_mask);
297  	kms->funcs->wait_flush(kms, crtc_mask);
298  	trace_msm_atomic_wait_flush_finish(crtc_mask);
299  
300  	vblank_put(kms, crtc_mask);
301  
302  	lock_crtcs(kms, crtc_mask);
303  	kms->funcs->complete_commit(kms, crtc_mask);
304  	unlock_crtcs(kms, crtc_mask);
305  	kms->funcs->disable_commit(kms);
306  
307  	drm_atomic_helper_commit_hw_done(state);
308  	drm_atomic_helper_cleanup_planes(dev, state);
309  
310  	trace_msm_atomic_commit_tail_finish(async, crtc_mask);
311  }
312