msm_atomic.c

  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_run_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 msm_drm_private *priv = dev->dev_private;
187	struct msm_kms *kms = priv->kms;
188	struct drm_crtc_state *old_crtc_state, *new_crtc_state;
189	struct drm_crtc *crtc;
190	int i, ret = 0;
191
192	/*
193	 * FIXME: stop setting allow_modeset and move this check to the DPU
194	 * driver.
195	 */
196	for_each_oldnew_crtc_in_state(state, crtc, old_crtc_state,
197				      new_crtc_state, i) {
198		if ((old_crtc_state->ctm && !new_crtc_state->ctm) ||
199		    (!old_crtc_state->ctm && new_crtc_state->ctm)) {
200			new_crtc_state->mode_changed = true;
201			state->allow_modeset = true;
202		}
203	}
204
205	if (kms && kms->funcs && kms->funcs->check_mode_changed)
206		ret = kms->funcs->check_mode_changed(kms, state);
207	if (ret)
208		return ret;
209
210	return drm_atomic_helper_check(dev, state);
211}
212
213void msm_atomic_commit_tail(struct drm_atomic_state *state)
214{
215	struct drm_device *dev = state->dev;
216	struct msm_drm_private *priv = dev->dev_private;
217	struct msm_kms *kms = priv->kms;
218	struct drm_crtc *async_crtc = NULL;
219	unsigned crtc_mask = get_crtc_mask(state);
220	bool async = can_do_async(state, &async_crtc);
221
222	trace_msm_atomic_commit_tail_start(async, crtc_mask);
223
224	kms->funcs->enable_commit(kms);
225
226	/*
227	 * Ensure any previous (potentially async) commit has
228	 * completed:
229	 */
230	lock_crtcs(kms, crtc_mask);
231	trace_msm_atomic_wait_flush_start(crtc_mask);
232	kms->funcs->wait_flush(kms, crtc_mask);
233	trace_msm_atomic_wait_flush_finish(crtc_mask);
234
235	atomic_set(&kms->fault_snapshot_capture, 0);
236
237	/*
238	 * Now that there is no in-progress flush, prepare the
239	 * current update:
240	 */
241	if (kms->funcs->prepare_commit)
242		kms->funcs->prepare_commit(kms, state);
243
244	/*
245	 * Push atomic updates down to hardware:
246	 */
247	drm_atomic_helper_commit_modeset_disables(dev, state);
248	drm_atomic_helper_commit_planes(dev, state, 0);
249	drm_atomic_helper_commit_modeset_enables(dev, state);
250
251	if (async) {
252		struct msm_pending_timer *timer =
253			&kms->pending_timers[drm_crtc_index(async_crtc)];
254
255		/* async updates are limited to single-crtc updates: */
256		WARN_ON(crtc_mask != drm_crtc_mask(async_crtc));
257
258		/*
259		 * Start timer if we don't already have an update pending
260		 * on this crtc:
261		 */
262		if (!(kms->pending_crtc_mask & crtc_mask)) {
263			ktime_t vsync_time, wakeup_time;
264
265			kms->pending_crtc_mask |= crtc_mask;
266
267			if (drm_crtc_next_vblank_start(async_crtc, &vsync_time))
268				goto fallback;
269
270			wakeup_time = ktime_sub(vsync_time, ms_to_ktime(1));
271
272			msm_hrtimer_queue_work(&timer->work, wakeup_time,
273					HRTIMER_MODE_ABS);
274		}
275
276		kms->funcs->disable_commit(kms);
277		unlock_crtcs(kms, crtc_mask);
278		/*
279		 * At this point, from drm core's perspective, we
280		 * are done with the atomic update, so we can just
281		 * go ahead and signal that it is done:
282		 */
283		drm_atomic_helper_commit_hw_done(state);
284		drm_atomic_helper_cleanup_planes(dev, state);
285
286		trace_msm_atomic_commit_tail_finish(async, crtc_mask);
287
288		return;
289	}
290
291fallback:
292	/*
293	 * If there is any async flush pending on updated crtcs, fold
294	 * them into the current flush.
295	 */
296	kms->pending_crtc_mask &= ~crtc_mask;
297
298	vblank_get(kms, crtc_mask);
299
300	/*
301	 * Flush hardware updates:
302	 */
303	trace_msm_atomic_flush_commit(crtc_mask);
304	kms->funcs->flush_commit(kms, crtc_mask);
305	unlock_crtcs(kms, crtc_mask);
306	/*
307	 * Wait for flush to complete:
308	 */
309	trace_msm_atomic_wait_flush_start(crtc_mask);
310	kms->funcs->wait_flush(kms, crtc_mask);
311	trace_msm_atomic_wait_flush_finish(crtc_mask);
312
313	vblank_put(kms, crtc_mask);
314
315	lock_crtcs(kms, crtc_mask);
316	kms->funcs->complete_commit(kms, crtc_mask);
317	unlock_crtcs(kms, crtc_mask);
318	kms->funcs->disable_commit(kms);
319
320	drm_atomic_helper_commit_hw_done(state);
321	drm_atomic_helper_cleanup_planes(dev, state);
322
323	trace_msm_atomic_commit_tail_finish(async, crtc_mask);
324}