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 (!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 */
172static 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
184int 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
202void 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
278fallback:
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}