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
12static 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(timer: &output->vblank_hrtimer,
24 interval: output->period_ns);
25 if (ret_overrun != 1)
26 pr_warn("%s: vblank timer overrun\n", __func__);
27
28 spin_lock(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(lock: &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(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(lock: &output->composer_lock);
51
52 ret = queue_work(wq: output->composer_workq, work: &state->composer_work);
53 if (!ret)
54 DRM_DEBUG_DRIVER("Composer worker already queued\n");
55 }
56
57 dma_fence_end_signalling(cookie: fence_cookie);
58
59 return HRTIMER_RESTART;
60}
61
62static 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, mode: &crtc->mode);
70
71 hrtimer_init(timer: &out->vblank_hrtimer, CLOCK_MONOTONIC, mode: HRTIMER_MODE_REL);
72 out->vblank_hrtimer.function = &vkms_vblank_simulate;
73 out->period_ns = ktime_set(secs: 0, nsecs: vblank->framedur_ns);
74 hrtimer_start(timer: &out->vblank_hrtimer, tim: out->period_ns, mode: HRTIMER_MODE_REL);
75
76 return 0;
77}
78
79static void vkms_disable_vblank(struct drm_crtc *crtc)
80{
81 struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
82
83 hrtimer_cancel(timer: &out->vblank_hrtimer);
84}
85
86static 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
118static struct drm_crtc_state *
119vkms_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(size: sizeof(*vkms_state), GFP_KERNEL);
127 if (!vkms_state)
128 return NULL;
129
130 __drm_atomic_helper_crtc_duplicate_state(crtc, state: &vkms_state->base);
131
132 INIT_WORK(&vkms_state->composer_work, vkms_composer_worker);
133
134 return &vkms_state->base;
135}
136
137static 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(objp: vkms_state->active_planes);
146 kfree(objp: vkms_state);
147}
148
149static void vkms_atomic_crtc_reset(struct drm_crtc *crtc)
150{
151 struct vkms_crtc_state *vkms_state =
152 kzalloc(size: sizeof(*vkms_state), GFP_KERNEL);
153
154 if (crtc->state)
155 vkms_atomic_crtc_destroy_state(crtc, state: crtc->state);
156
157 __drm_atomic_helper_crtc_reset(crtc, state: &vkms_state->base);
158 if (vkms_state)
159 INIT_WORK(&vkms_state->composer_work, vkms_composer_worker);
160}
161
162static const struct drm_crtc_funcs vkms_crtc_funcs = {
163 .set_config = drm_atomic_helper_set_config,
164 .page_flip = drm_atomic_helper_page_flip,
165 .reset = vkms_atomic_crtc_reset,
166 .atomic_duplicate_state = vkms_atomic_crtc_duplicate_state,
167 .atomic_destroy_state = vkms_atomic_crtc_destroy_state,
168 .enable_vblank = vkms_enable_vblank,
169 .disable_vblank = vkms_disable_vblank,
170 .get_vblank_timestamp = vkms_get_vblank_timestamp,
171 .get_crc_sources = vkms_get_crc_sources,
172 .set_crc_source = vkms_set_crc_source,
173 .verify_crc_source = vkms_verify_crc_source,
174};
175
176static int vkms_crtc_atomic_check(struct drm_crtc *crtc,
177 struct drm_atomic_state *state)
178{
179 struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state,
180 crtc);
181 struct vkms_crtc_state *vkms_state = to_vkms_crtc_state(crtc_state);
182 struct drm_plane *plane;
183 struct drm_plane_state *plane_state;
184 int i = 0, ret;
185
186 if (vkms_state->active_planes)
187 return 0;
188
189 ret = drm_atomic_add_affected_planes(state: crtc_state->state, crtc);
190 if (ret < 0)
191 return ret;
192
193 drm_for_each_plane_mask(plane, crtc->dev, crtc_state->plane_mask) {
194 plane_state = drm_atomic_get_existing_plane_state(state: crtc_state->state,
195 plane);
196 WARN_ON(!plane_state);
197
198 if (!plane_state->visible)
199 continue;
200
201 i++;
202 }
203
204 vkms_state->active_planes = kcalloc(n: i, size: sizeof(plane), GFP_KERNEL);
205 if (!vkms_state->active_planes)
206 return -ENOMEM;
207 vkms_state->num_active_planes = i;
208
209 i = 0;
210 drm_for_each_plane_mask(plane, crtc->dev, crtc_state->plane_mask) {
211 plane_state = drm_atomic_get_existing_plane_state(state: crtc_state->state,
212 plane);
213
214 if (!plane_state->visible)
215 continue;
216
217 vkms_state->active_planes[i++] =
218 to_vkms_plane_state(plane_state);
219 }
220
221 return 0;
222}
223
224static void vkms_crtc_atomic_enable(struct drm_crtc *crtc,
225 struct drm_atomic_state *state)
226{
227 drm_crtc_vblank_on(crtc);
228}
229
230static void vkms_crtc_atomic_disable(struct drm_crtc *crtc,
231 struct drm_atomic_state *state)
232{
233 drm_crtc_vblank_off(crtc);
234}
235
236static void vkms_crtc_atomic_begin(struct drm_crtc *crtc,
237 struct drm_atomic_state *state)
238{
239 struct vkms_output *vkms_output = drm_crtc_to_vkms_output(crtc);
240
241 /* This lock is held across the atomic commit to block vblank timer
242 * from scheduling vkms_composer_worker until the composer is updated
243 */
244 spin_lock_irq(lock: &vkms_output->lock);
245}
246
247static void vkms_crtc_atomic_flush(struct drm_crtc *crtc,
248 struct drm_atomic_state *state)
249{
250 struct vkms_output *vkms_output = drm_crtc_to_vkms_output(crtc);
251
252 if (crtc->state->event) {
253 spin_lock(lock: &crtc->dev->event_lock);
254
255 if (drm_crtc_vblank_get(crtc) != 0)
256 drm_crtc_send_vblank_event(crtc, e: crtc->state->event);
257 else
258 drm_crtc_arm_vblank_event(crtc, e: crtc->state->event);
259
260 spin_unlock(lock: &crtc->dev->event_lock);
261
262 crtc->state->event = NULL;
263 }
264
265 vkms_output->composer_state = to_vkms_crtc_state(crtc->state);
266
267 spin_unlock_irq(lock: &vkms_output->lock);
268}
269
270static const struct drm_crtc_helper_funcs vkms_crtc_helper_funcs = {
271 .atomic_check = vkms_crtc_atomic_check,
272 .atomic_begin = vkms_crtc_atomic_begin,
273 .atomic_flush = vkms_crtc_atomic_flush,
274 .atomic_enable = vkms_crtc_atomic_enable,
275 .atomic_disable = vkms_crtc_atomic_disable,
276};
277
278int vkms_crtc_init(struct drm_device *dev, struct drm_crtc *crtc,
279 struct drm_plane *primary, struct drm_plane *cursor)
280{
281 struct vkms_output *vkms_out = drm_crtc_to_vkms_output(crtc);
282 int ret;
283
284 ret = drmm_crtc_init_with_planes(dev, crtc, primary, cursor,
285 funcs: &vkms_crtc_funcs, NULL);
286 if (ret) {
287 DRM_ERROR("Failed to init CRTC\n");
288 return ret;
289 }
290
291 drm_crtc_helper_add(crtc, funcs: &vkms_crtc_helper_funcs);
292
293 drm_mode_crtc_set_gamma_size(crtc, VKMS_LUT_SIZE);
294 drm_crtc_enable_color_mgmt(crtc, degamma_lut_size: 0, has_ctm: false, VKMS_LUT_SIZE);
295
296 spin_lock_init(&vkms_out->lock);
297 spin_lock_init(&vkms_out->composer_lock);
298
299 vkms_out->composer_workq = alloc_ordered_workqueue("vkms_composer", 0);
300 if (!vkms_out->composer_workq)
301 return -ENOMEM;
302
303 return ret;
304}
305

source code of linux/drivers/gpu/drm/vkms/vkms_crtc.c