1 // SPDX-License-Identifier: GPL-2.0+
2
3 #include <linux/dma-fence.h>
4
5 #include <drm/drm_atomic.h>
6 #include <drm/drm_atomic_helper.h>
7 #include <drm/drm_probe_helper.h>
8 #include <drm/drm_vblank.h>
9
10 #include "vkms_drv.h"
11
vkms_vblank_simulate(struct hrtimer * timer)12 static enum hrtimer_restart vkms_vblank_simulate(struct hrtimer *timer)
13 {
14 struct vkms_output *output = container_of(timer, struct vkms_output,
15 vblank_hrtimer);
16 struct drm_crtc *crtc = &output->crtc;
17 struct vkms_crtc_state *state;
18 u64 ret_overrun;
19 bool ret, fence_cookie;
20
21 fence_cookie = dma_fence_begin_signalling();
22
23 ret_overrun = hrtimer_forward_now(&output->vblank_hrtimer,
24 output->period_ns);
25 if (ret_overrun != 1)
26 pr_warn("%s: vblank timer overrun\n", __func__);
27
28 spin_lock(&output->lock);
29 ret = drm_crtc_handle_vblank(crtc);
30 if (!ret)
31 DRM_ERROR("vkms failure on handling vblank");
32
33 state = output->composer_state;
34 spin_unlock(&output->lock);
35
36 if (state && output->composer_enabled) {
37 u64 frame = drm_crtc_accurate_vblank_count(crtc);
38
39 /* update frame_start only if a queued vkms_composer_worker()
40 * has read the data
41 */
42 spin_lock(&output->composer_lock);
43 if (!state->crc_pending)
44 state->frame_start = frame;
45 else
46 DRM_DEBUG_DRIVER("crc worker falling behind, frame_start: %llu, frame_end: %llu\n",
47 state->frame_start, frame);
48 state->frame_end = frame;
49 state->crc_pending = true;
50 spin_unlock(&output->composer_lock);
51
52 ret = queue_work(output->composer_workq, &state->composer_work);
53 if (!ret)
54 DRM_DEBUG_DRIVER("Composer worker already queued\n");
55 }
56
57 dma_fence_end_signalling(fence_cookie);
58
59 return HRTIMER_RESTART;
60 }
61
vkms_enable_vblank(struct drm_crtc * crtc)62 static int vkms_enable_vblank(struct drm_crtc *crtc)
63 {
64 struct drm_device *dev = crtc->dev;
65 unsigned int pipe = drm_crtc_index(crtc);
66 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
67 struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
68
69 drm_calc_timestamping_constants(crtc, &crtc->mode);
70
71 hrtimer_init(&out->vblank_hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
72 out->vblank_hrtimer.function = &vkms_vblank_simulate;
73 out->period_ns = ktime_set(0, vblank->framedur_ns);
74 hrtimer_start(&out->vblank_hrtimer, out->period_ns, HRTIMER_MODE_REL);
75
76 return 0;
77 }
78
vkms_disable_vblank(struct drm_crtc * crtc)79 static void vkms_disable_vblank(struct drm_crtc *crtc)
80 {
81 struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
82
83 hrtimer_cancel(&out->vblank_hrtimer);
84 }
85
vkms_get_vblank_timestamp(struct drm_crtc * crtc,int * max_error,ktime_t * vblank_time,bool in_vblank_irq)86 static bool vkms_get_vblank_timestamp(struct drm_crtc *crtc,
87 int *max_error, ktime_t *vblank_time,
88 bool in_vblank_irq)
89 {
90 struct drm_device *dev = crtc->dev;
91 unsigned int pipe = crtc->index;
92 struct vkms_device *vkmsdev = drm_device_to_vkms_device(dev);
93 struct vkms_output *output = &vkmsdev->output;
94 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
95
96 if (!READ_ONCE(vblank->enabled)) {
97 *vblank_time = ktime_get();
98 return true;
99 }
100
101 *vblank_time = READ_ONCE(output->vblank_hrtimer.node.expires);
102
103 if (WARN_ON(*vblank_time == vblank->time))
104 return true;
105
106 /*
107 * To prevent races we roll the hrtimer forward before we do any
108 * interrupt processing - this is how real hw works (the interrupt is
109 * only generated after all the vblank registers are updated) and what
110 * the vblank core expects. Therefore we need to always correct the
111 * timestampe by one frame.
112 */
113 *vblank_time -= output->period_ns;
114
115 return true;
116 }
117
118 static struct drm_crtc_state *
vkms_atomic_crtc_duplicate_state(struct drm_crtc * crtc)119 vkms_atomic_crtc_duplicate_state(struct drm_crtc *crtc)
120 {
121 struct vkms_crtc_state *vkms_state;
122
123 if (WARN_ON(!crtc->state))
124 return NULL;
125
126 vkms_state = kzalloc(sizeof(*vkms_state), GFP_KERNEL);
127 if (!vkms_state)
128 return NULL;
129
130 __drm_atomic_helper_crtc_duplicate_state(crtc, &vkms_state->base);
131
132 INIT_WORK(&vkms_state->composer_work, vkms_composer_worker);
133
134 return &vkms_state->base;
135 }
136
vkms_atomic_crtc_destroy_state(struct drm_crtc * crtc,struct drm_crtc_state * state)137 static void vkms_atomic_crtc_destroy_state(struct drm_crtc *crtc,
138 struct drm_crtc_state *state)
139 {
140 struct vkms_crtc_state *vkms_state = to_vkms_crtc_state(state);
141
142 __drm_atomic_helper_crtc_destroy_state(state);
143
144 WARN_ON(work_pending(&vkms_state->composer_work));
145 kfree(vkms_state->active_planes);
146 kfree(vkms_state);
147 }
148
vkms_atomic_crtc_reset(struct drm_crtc * crtc)149 static void vkms_atomic_crtc_reset(struct drm_crtc *crtc)
150 {
151 struct vkms_crtc_state *vkms_state =
152 kzalloc(sizeof(*vkms_state), GFP_KERNEL);
153
154 if (crtc->state)
155 vkms_atomic_crtc_destroy_state(crtc, crtc->state);
156
157 __drm_atomic_helper_crtc_reset(crtc, &vkms_state->base);
158 if (vkms_state)
159 INIT_WORK(&vkms_state->composer_work, vkms_composer_worker);
160 }
161
162 static const struct drm_crtc_funcs vkms_crtc_funcs = {
163 .set_config = drm_atomic_helper_set_config,
164 .destroy = drm_crtc_cleanup,
165 .page_flip = drm_atomic_helper_page_flip,
166 .reset = vkms_atomic_crtc_reset,
167 .atomic_duplicate_state = vkms_atomic_crtc_duplicate_state,
168 .atomic_destroy_state = vkms_atomic_crtc_destroy_state,
169 .enable_vblank = vkms_enable_vblank,
170 .disable_vblank = vkms_disable_vblank,
171 .get_vblank_timestamp = vkms_get_vblank_timestamp,
172 .get_crc_sources = vkms_get_crc_sources,
173 .set_crc_source = vkms_set_crc_source,
174 .verify_crc_source = vkms_verify_crc_source,
175 };
176
vkms_crtc_atomic_check(struct drm_crtc * crtc,struct drm_atomic_state * state)177 static int vkms_crtc_atomic_check(struct drm_crtc *crtc,
178 struct drm_atomic_state *state)
179 {
180 struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state,
181 crtc);
182 struct vkms_crtc_state *vkms_state = to_vkms_crtc_state(crtc_state);
183 struct drm_plane *plane;
184 struct drm_plane_state *plane_state;
185 int i = 0, ret;
186
187 if (vkms_state->active_planes)
188 return 0;
189
190 ret = drm_atomic_add_affected_planes(crtc_state->state, crtc);
191 if (ret < 0)
192 return ret;
193
194 drm_for_each_plane_mask(plane, crtc->dev, crtc_state->plane_mask) {
195 plane_state = drm_atomic_get_existing_plane_state(crtc_state->state,
196 plane);
197 WARN_ON(!plane_state);
198
199 if (!plane_state->visible)
200 continue;
201
202 i++;
203 }
204
205 vkms_state->active_planes = kcalloc(i, sizeof(plane), GFP_KERNEL);
206 if (!vkms_state->active_planes)
207 return -ENOMEM;
208 vkms_state->num_active_planes = i;
209
210 i = 0;
211 drm_for_each_plane_mask(plane, crtc->dev, crtc_state->plane_mask) {
212 plane_state = drm_atomic_get_existing_plane_state(crtc_state->state,
213 plane);
214
215 if (!plane_state->visible)
216 continue;
217
218 vkms_state->active_planes[i++] =
219 to_vkms_plane_state(plane_state);
220 }
221
222 return 0;
223 }
224
vkms_crtc_atomic_enable(struct drm_crtc * crtc,struct drm_atomic_state * state)225 static void vkms_crtc_atomic_enable(struct drm_crtc *crtc,
226 struct drm_atomic_state *state)
227 {
228 drm_crtc_vblank_on(crtc);
229 }
230
vkms_crtc_atomic_disable(struct drm_crtc * crtc,struct drm_atomic_state * state)231 static void vkms_crtc_atomic_disable(struct drm_crtc *crtc,
232 struct drm_atomic_state *state)
233 {
234 drm_crtc_vblank_off(crtc);
235 }
236
vkms_crtc_atomic_begin(struct drm_crtc * crtc,struct drm_atomic_state * state)237 static void vkms_crtc_atomic_begin(struct drm_crtc *crtc,
238 struct drm_atomic_state *state)
239 {
240 struct vkms_output *vkms_output = drm_crtc_to_vkms_output(crtc);
241
242 /* This lock is held across the atomic commit to block vblank timer
243 * from scheduling vkms_composer_worker until the composer is updated
244 */
245 spin_lock_irq(&vkms_output->lock);
246 }
247
vkms_crtc_atomic_flush(struct drm_crtc * crtc,struct drm_atomic_state * state)248 static void vkms_crtc_atomic_flush(struct drm_crtc *crtc,
249 struct drm_atomic_state *state)
250 {
251 struct vkms_output *vkms_output = drm_crtc_to_vkms_output(crtc);
252
253 if (crtc->state->event) {
254 spin_lock(&crtc->dev->event_lock);
255
256 if (drm_crtc_vblank_get(crtc) != 0)
257 drm_crtc_send_vblank_event(crtc, crtc->state->event);
258 else
259 drm_crtc_arm_vblank_event(crtc, crtc->state->event);
260
261 spin_unlock(&crtc->dev->event_lock);
262
263 crtc->state->event = NULL;
264 }
265
266 vkms_output->composer_state = to_vkms_crtc_state(crtc->state);
267
268 spin_unlock_irq(&vkms_output->lock);
269 }
270
271 static const struct drm_crtc_helper_funcs vkms_crtc_helper_funcs = {
272 .atomic_check = vkms_crtc_atomic_check,
273 .atomic_begin = vkms_crtc_atomic_begin,
274 .atomic_flush = vkms_crtc_atomic_flush,
275 .atomic_enable = vkms_crtc_atomic_enable,
276 .atomic_disable = vkms_crtc_atomic_disable,
277 };
278
vkms_crtc_init(struct drm_device * dev,struct drm_crtc * crtc,struct drm_plane * primary,struct drm_plane * cursor)279 int vkms_crtc_init(struct drm_device *dev, struct drm_crtc *crtc,
280 struct drm_plane *primary, struct drm_plane *cursor)
281 {
282 struct vkms_output *vkms_out = drm_crtc_to_vkms_output(crtc);
283 int ret;
284
285 ret = drm_crtc_init_with_planes(dev, crtc, primary, cursor,
286 &vkms_crtc_funcs, NULL);
287 if (ret) {
288 DRM_ERROR("Failed to init CRTC\n");
289 return ret;
290 }
291
292 drm_crtc_helper_add(crtc, &vkms_crtc_helper_funcs);
293
294 spin_lock_init(&vkms_out->lock);
295 spin_lock_init(&vkms_out->composer_lock);
296
297 vkms_out->composer_workq = alloc_ordered_workqueue("vkms_composer", 0);
298 if (!vkms_out->composer_workq)
299 return -ENOMEM;
300
301 return ret;
302 }
303