xref: /openbmc/linux/drivers/gpu/drm/msm/msm_atomic.c (revision a44e4f3a)
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_gem_framebuffer_helper.h>
9 #include <drm/drm_vblank.h>
10 
11 #include "msm_atomic_trace.h"
12 #include "msm_drv.h"
13 #include "msm_gem.h"
14 #include "msm_kms.h"
15 
16 int msm_atomic_prepare_fb(struct drm_plane *plane,
17 			  struct drm_plane_state *new_state)
18 {
19 	struct msm_drm_private *priv = plane->dev->dev_private;
20 	struct msm_kms *kms = priv->kms;
21 
22 	if (!new_state->fb)
23 		return 0;
24 
25 	drm_gem_fb_prepare_fb(plane, new_state);
26 
27 	return msm_framebuffer_prepare(new_state->fb, kms->aspace);
28 }
29 
30 static void msm_atomic_async_commit(struct msm_kms *kms, int crtc_idx)
31 {
32 	unsigned crtc_mask = BIT(crtc_idx);
33 
34 	trace_msm_atomic_async_commit_start(crtc_mask);
35 
36 	mutex_lock(&kms->commit_lock);
37 
38 	if (!(kms->pending_crtc_mask & crtc_mask)) {
39 		mutex_unlock(&kms->commit_lock);
40 		goto out;
41 	}
42 
43 	kms->pending_crtc_mask &= ~crtc_mask;
44 
45 	kms->funcs->enable_commit(kms);
46 
47 	/*
48 	 * Flush hardware updates:
49 	 */
50 	trace_msm_atomic_flush_commit(crtc_mask);
51 	kms->funcs->flush_commit(kms, crtc_mask);
52 	mutex_unlock(&kms->commit_lock);
53 
54 	/*
55 	 * Wait for flush to complete:
56 	 */
57 	trace_msm_atomic_wait_flush_start(crtc_mask);
58 	kms->funcs->wait_flush(kms, crtc_mask);
59 	trace_msm_atomic_wait_flush_finish(crtc_mask);
60 
61 	mutex_lock(&kms->commit_lock);
62 	kms->funcs->complete_commit(kms, crtc_mask);
63 	mutex_unlock(&kms->commit_lock);
64 	kms->funcs->disable_commit(kms);
65 
66 out:
67 	trace_msm_atomic_async_commit_finish(crtc_mask);
68 }
69 
70 static enum hrtimer_restart msm_atomic_pending_timer(struct hrtimer *t)
71 {
72 	struct msm_pending_timer *timer = container_of(t,
73 			struct msm_pending_timer, timer);
74 	struct msm_drm_private *priv = timer->kms->dev->dev_private;
75 
76 	queue_work(priv->wq, &timer->work);
77 
78 	return HRTIMER_NORESTART;
79 }
80 
81 static void msm_atomic_pending_work(struct work_struct *work)
82 {
83 	struct msm_pending_timer *timer = container_of(work,
84 			struct msm_pending_timer, work);
85 
86 	msm_atomic_async_commit(timer->kms, timer->crtc_idx);
87 }
88 
89 void msm_atomic_init_pending_timer(struct msm_pending_timer *timer,
90 		struct msm_kms *kms, int crtc_idx)
91 {
92 	timer->kms = kms;
93 	timer->crtc_idx = crtc_idx;
94 	hrtimer_init(&timer->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
95 	timer->timer.function = msm_atomic_pending_timer;
96 	INIT_WORK(&timer->work, msm_atomic_pending_work);
97 }
98 
99 static bool can_do_async(struct drm_atomic_state *state,
100 		struct drm_crtc **async_crtc)
101 {
102 	struct drm_connector_state *connector_state;
103 	struct drm_connector *connector;
104 	struct drm_crtc_state *crtc_state;
105 	struct drm_crtc *crtc;
106 	int i, num_crtcs = 0;
107 
108 	if (!(state->legacy_cursor_update || state->async_update))
109 		return false;
110 
111 	/* any connector change, means slow path: */
112 	for_each_new_connector_in_state(state, connector, connector_state, i)
113 		return false;
114 
115 	for_each_new_crtc_in_state(state, crtc, crtc_state, i) {
116 		if (drm_atomic_crtc_needs_modeset(crtc_state))
117 			return false;
118 		if (++num_crtcs > 1)
119 			return false;
120 		*async_crtc = crtc;
121 	}
122 
123 	return true;
124 }
125 
126 /* Get bitmask of crtcs that will need to be flushed.  The bitmask
127  * can be used with for_each_crtc_mask() iterator, to iterate
128  * effected crtcs without needing to preserve the atomic state.
129  */
130 static unsigned get_crtc_mask(struct drm_atomic_state *state)
131 {
132 	struct drm_crtc_state *crtc_state;
133 	struct drm_crtc *crtc;
134 	unsigned i, mask = 0;
135 
136 	for_each_new_crtc_in_state(state, crtc, crtc_state, i)
137 		mask |= drm_crtc_mask(crtc);
138 
139 	return mask;
140 }
141 
142 void msm_atomic_commit_tail(struct drm_atomic_state *state)
143 {
144 	struct drm_device *dev = state->dev;
145 	struct msm_drm_private *priv = dev->dev_private;
146 	struct msm_kms *kms = priv->kms;
147 	struct drm_crtc *async_crtc = NULL;
148 	unsigned crtc_mask = get_crtc_mask(state);
149 	bool async = kms->funcs->vsync_time &&
150 			can_do_async(state, &async_crtc);
151 
152 	trace_msm_atomic_commit_tail_start(async, crtc_mask);
153 
154 	kms->funcs->enable_commit(kms);
155 
156 	/*
157 	 * Ensure any previous (potentially async) commit has
158 	 * completed:
159 	 */
160 	trace_msm_atomic_wait_flush_start(crtc_mask);
161 	kms->funcs->wait_flush(kms, crtc_mask);
162 	trace_msm_atomic_wait_flush_finish(crtc_mask);
163 
164 	mutex_lock(&kms->commit_lock);
165 
166 	/*
167 	 * Now that there is no in-progress flush, prepare the
168 	 * current update:
169 	 */
170 	kms->funcs->prepare_commit(kms, state);
171 
172 	/*
173 	 * Push atomic updates down to hardware:
174 	 */
175 	drm_atomic_helper_commit_modeset_disables(dev, state);
176 	drm_atomic_helper_commit_planes(dev, state, 0);
177 	drm_atomic_helper_commit_modeset_enables(dev, state);
178 
179 	if (async) {
180 		struct msm_pending_timer *timer =
181 			&kms->pending_timers[drm_crtc_index(async_crtc)];
182 
183 		/* async updates are limited to single-crtc updates: */
184 		WARN_ON(crtc_mask != drm_crtc_mask(async_crtc));
185 
186 		/*
187 		 * Start timer if we don't already have an update pending
188 		 * on this crtc:
189 		 */
190 		if (!(kms->pending_crtc_mask & crtc_mask)) {
191 			ktime_t vsync_time, wakeup_time;
192 
193 			kms->pending_crtc_mask |= crtc_mask;
194 
195 			vsync_time = kms->funcs->vsync_time(kms, async_crtc);
196 			wakeup_time = ktime_sub(vsync_time, ms_to_ktime(1));
197 
198 			hrtimer_start(&timer->timer, wakeup_time,
199 					HRTIMER_MODE_ABS);
200 		}
201 
202 		kms->funcs->disable_commit(kms);
203 		mutex_unlock(&kms->commit_lock);
204 
205 		/*
206 		 * At this point, from drm core's perspective, we
207 		 * are done with the atomic update, so we can just
208 		 * go ahead and signal that it is done:
209 		 */
210 		drm_atomic_helper_commit_hw_done(state);
211 		drm_atomic_helper_cleanup_planes(dev, state);
212 
213 		trace_msm_atomic_commit_tail_finish(async, crtc_mask);
214 
215 		return;
216 	}
217 
218 	/*
219 	 * If there is any async flush pending on updated crtcs, fold
220 	 * them into the current flush.
221 	 */
222 	kms->pending_crtc_mask &= ~crtc_mask;
223 
224 	/*
225 	 * Flush hardware updates:
226 	 */
227 	trace_msm_atomic_flush_commit(crtc_mask);
228 	kms->funcs->flush_commit(kms, crtc_mask);
229 	mutex_unlock(&kms->commit_lock);
230 
231 	/*
232 	 * Wait for flush to complete:
233 	 */
234 	trace_msm_atomic_wait_flush_start(crtc_mask);
235 	kms->funcs->wait_flush(kms, crtc_mask);
236 	trace_msm_atomic_wait_flush_finish(crtc_mask);
237 
238 	mutex_lock(&kms->commit_lock);
239 	kms->funcs->complete_commit(kms, crtc_mask);
240 	mutex_unlock(&kms->commit_lock);
241 	kms->funcs->disable_commit(kms);
242 
243 	drm_atomic_helper_commit_hw_done(state);
244 	drm_atomic_helper_cleanup_planes(dev, state);
245 
246 	trace_msm_atomic_commit_tail_finish(async, crtc_mask);
247 }
248