1 | /* |
2 | * drm_irq.c IRQ and vblank support |
3 | * |
4 | * \author Rickard E. (Rik) Faith <faith@valinux.com> |
5 | * \author Gareth Hughes <gareth@valinux.com> |
6 | * |
7 | * Permission is hereby granted, free of charge, to any person obtaining a |
8 | * copy of this software and associated documentation files (the "Software"), |
9 | * to deal in the Software without restriction, including without limitation |
10 | * the rights to use, copy, modify, merge, publish, distribute, sublicense, |
11 | * and/or sell copies of the Software, and to permit persons to whom the |
12 | * Software is furnished to do so, subject to the following conditions: |
13 | * |
14 | * The above copyright notice and this permission notice (including the next |
15 | * paragraph) shall be included in all copies or substantial portions of the |
16 | * Software. |
17 | * |
18 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
19 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
20 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
21 | * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR |
22 | * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, |
23 | * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR |
24 | * OTHER DEALINGS IN THE SOFTWARE. |
25 | */ |
26 | |
27 | #include <linux/export.h> |
28 | #include <linux/kthread.h> |
29 | #include <linux/moduleparam.h> |
30 | |
31 | #include <drm/drm_crtc.h> |
32 | #include <drm/drm_drv.h> |
33 | #include <drm/drm_framebuffer.h> |
34 | #include <drm/drm_managed.h> |
35 | #include <drm/drm_modeset_helper_vtables.h> |
36 | #include <drm/drm_print.h> |
37 | #include <drm/drm_vblank.h> |
38 | |
39 | #include "drm_internal.h" |
40 | #include "drm_trace.h" |
41 | |
42 | /** |
43 | * DOC: vblank handling |
44 | * |
45 | * From the computer's perspective, every time the monitor displays |
46 | * a new frame the scanout engine has "scanned out" the display image |
47 | * from top to bottom, one row of pixels at a time. The current row |
48 | * of pixels is referred to as the current scanline. |
49 | * |
50 | * In addition to the display's visible area, there's usually a couple of |
51 | * extra scanlines which aren't actually displayed on the screen. |
52 | * These extra scanlines don't contain image data and are occasionally used |
53 | * for features like audio and infoframes. The region made up of these |
54 | * scanlines is referred to as the vertical blanking region, or vblank for |
55 | * short. |
56 | * |
57 | * For historical reference, the vertical blanking period was designed to |
58 | * give the electron gun (on CRTs) enough time to move back to the top of |
59 | * the screen to start scanning out the next frame. Similar for horizontal |
60 | * blanking periods. They were designed to give the electron gun enough |
61 | * time to move back to the other side of the screen to start scanning the |
62 | * next scanline. |
63 | * |
64 | * :: |
65 | * |
66 | * |
67 | * physical → ⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽ |
68 | * top of | | |
69 | * display | | |
70 | * | New frame | |
71 | * | | |
72 | * |↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓| |
73 | * |~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| ← Scanline, |
74 | * |↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓| updates the |
75 | * | | frame as it |
76 | * | | travels down |
77 | * | | ("scan out") |
78 | * | Old frame | |
79 | * | | |
80 | * | | |
81 | * | | |
82 | * | | physical |
83 | * | | bottom of |
84 | * vertical |⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽| ← display |
85 | * blanking ┆xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx┆ |
86 | * region → ┆xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx┆ |
87 | * ┆xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx┆ |
88 | * start of → ⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽ |
89 | * new frame |
90 | * |
91 | * "Physical top of display" is the reference point for the high-precision/ |
92 | * corrected timestamp. |
93 | * |
94 | * On a lot of display hardware, programming needs to take effect during the |
95 | * vertical blanking period so that settings like gamma, the image buffer |
96 | * buffer to be scanned out, etc. can safely be changed without showing |
97 | * any visual artifacts on the screen. In some unforgiving hardware, some of |
98 | * this programming has to both start and end in the same vblank. To help |
99 | * with the timing of the hardware programming, an interrupt is usually |
100 | * available to notify the driver when it can start the updating of registers. |
101 | * The interrupt is in this context named the vblank interrupt. |
102 | * |
103 | * The vblank interrupt may be fired at different points depending on the |
104 | * hardware. Some hardware implementations will fire the interrupt when the |
105 | * new frame start, other implementations will fire the interrupt at different |
106 | * points in time. |
107 | * |
108 | * Vertical blanking plays a major role in graphics rendering. To achieve |
109 | * tear-free display, users must synchronize page flips and/or rendering to |
110 | * vertical blanking. The DRM API offers ioctls to perform page flips |
111 | * synchronized to vertical blanking and wait for vertical blanking. |
112 | * |
113 | * The DRM core handles most of the vertical blanking management logic, which |
114 | * involves filtering out spurious interrupts, keeping race-free blanking |
115 | * counters, coping with counter wrap-around and resets and keeping use counts. |
116 | * It relies on the driver to generate vertical blanking interrupts and |
117 | * optionally provide a hardware vertical blanking counter. |
118 | * |
119 | * Drivers must initialize the vertical blanking handling core with a call to |
120 | * drm_vblank_init(). Minimally, a driver needs to implement |
121 | * &drm_crtc_funcs.enable_vblank and &drm_crtc_funcs.disable_vblank plus call |
122 | * drm_crtc_handle_vblank() in its vblank interrupt handler for working vblank |
123 | * support. |
124 | * |
125 | * Vertical blanking interrupts can be enabled by the DRM core or by drivers |
126 | * themselves (for instance to handle page flipping operations). The DRM core |
127 | * maintains a vertical blanking use count to ensure that the interrupts are not |
128 | * disabled while a user still needs them. To increment the use count, drivers |
129 | * call drm_crtc_vblank_get() and release the vblank reference again with |
130 | * drm_crtc_vblank_put(). In between these two calls vblank interrupts are |
131 | * guaranteed to be enabled. |
132 | * |
133 | * On many hardware disabling the vblank interrupt cannot be done in a race-free |
134 | * manner, see &drm_driver.vblank_disable_immediate and |
135 | * &drm_driver.max_vblank_count. In that case the vblank core only disables the |
136 | * vblanks after a timer has expired, which can be configured through the |
137 | * ``vblankoffdelay`` module parameter. |
138 | * |
139 | * Drivers for hardware without support for vertical-blanking interrupts |
140 | * must not call drm_vblank_init(). For such drivers, atomic helpers will |
141 | * automatically generate fake vblank events as part of the display update. |
142 | * This functionality also can be controlled by the driver by enabling and |
143 | * disabling struct drm_crtc_state.no_vblank. |
144 | */ |
145 | |
146 | /* Retry timestamp calculation up to 3 times to satisfy |
147 | * drm_timestamp_precision before giving up. |
148 | */ |
149 | #define DRM_TIMESTAMP_MAXRETRIES 3 |
150 | |
151 | /* Threshold in nanoseconds for detection of redundant |
152 | * vblank irq in drm_handle_vblank(). 1 msec should be ok. |
153 | */ |
154 | #define DRM_REDUNDANT_VBLIRQ_THRESH_NS 1000000 |
155 | |
156 | static bool |
157 | drm_get_last_vbltimestamp(struct drm_device *dev, unsigned int pipe, |
158 | ktime_t *tvblank, bool in_vblank_irq); |
159 | |
160 | static unsigned int drm_timestamp_precision = 20; /* Default to 20 usecs. */ |
161 | |
162 | static int drm_vblank_offdelay = 5000; /* Default to 5000 msecs. */ |
163 | |
164 | module_param_named(vblankoffdelay, drm_vblank_offdelay, int, 0600); |
165 | module_param_named(timestamp_precision_usec, drm_timestamp_precision, int, 0600); |
166 | MODULE_PARM_DESC(vblankoffdelay, "Delay until vblank irq auto-disable [msecs] (0: never disable, <0: disable immediately)" ); |
167 | MODULE_PARM_DESC(timestamp_precision_usec, "Max. error on timestamps [usecs]" ); |
168 | |
169 | static void store_vblank(struct drm_device *dev, unsigned int pipe, |
170 | u32 vblank_count_inc, |
171 | ktime_t t_vblank, u32 last) |
172 | { |
173 | struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; |
174 | |
175 | assert_spin_locked(&dev->vblank_time_lock); |
176 | |
177 | vblank->last = last; |
178 | |
179 | write_seqlock(sl: &vblank->seqlock); |
180 | vblank->time = t_vblank; |
181 | atomic64_add(i: vblank_count_inc, v: &vblank->count); |
182 | write_sequnlock(sl: &vblank->seqlock); |
183 | } |
184 | |
185 | static u32 drm_max_vblank_count(struct drm_device *dev, unsigned int pipe) |
186 | { |
187 | struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; |
188 | |
189 | return vblank->max_vblank_count ?: dev->max_vblank_count; |
190 | } |
191 | |
192 | /* |
193 | * "No hw counter" fallback implementation of .get_vblank_counter() hook, |
194 | * if there is no usable hardware frame counter available. |
195 | */ |
196 | static u32 drm_vblank_no_hw_counter(struct drm_device *dev, unsigned int pipe) |
197 | { |
198 | drm_WARN_ON_ONCE(dev, drm_max_vblank_count(dev, pipe) != 0); |
199 | return 0; |
200 | } |
201 | |
202 | static u32 __get_vblank_counter(struct drm_device *dev, unsigned int pipe) |
203 | { |
204 | if (drm_core_check_feature(dev, feature: DRIVER_MODESET)) { |
205 | struct drm_crtc *crtc = drm_crtc_from_index(dev, idx: pipe); |
206 | |
207 | if (drm_WARN_ON(dev, !crtc)) |
208 | return 0; |
209 | |
210 | if (crtc->funcs->get_vblank_counter) |
211 | return crtc->funcs->get_vblank_counter(crtc); |
212 | } |
213 | #ifdef CONFIG_DRM_LEGACY |
214 | else if (dev->driver->get_vblank_counter) { |
215 | return dev->driver->get_vblank_counter(dev, pipe); |
216 | } |
217 | #endif |
218 | |
219 | return drm_vblank_no_hw_counter(dev, pipe); |
220 | } |
221 | |
222 | /* |
223 | * Reset the stored timestamp for the current vblank count to correspond |
224 | * to the last vblank occurred. |
225 | * |
226 | * Only to be called from drm_crtc_vblank_on(). |
227 | * |
228 | * Note: caller must hold &drm_device.vbl_lock since this reads & writes |
229 | * device vblank fields. |
230 | */ |
231 | static void drm_reset_vblank_timestamp(struct drm_device *dev, unsigned int pipe) |
232 | { |
233 | u32 cur_vblank; |
234 | bool rc; |
235 | ktime_t t_vblank; |
236 | int count = DRM_TIMESTAMP_MAXRETRIES; |
237 | |
238 | spin_lock(lock: &dev->vblank_time_lock); |
239 | |
240 | /* |
241 | * sample the current counter to avoid random jumps |
242 | * when drm_vblank_enable() applies the diff |
243 | */ |
244 | do { |
245 | cur_vblank = __get_vblank_counter(dev, pipe); |
246 | rc = drm_get_last_vbltimestamp(dev, pipe, tvblank: &t_vblank, in_vblank_irq: false); |
247 | } while (cur_vblank != __get_vblank_counter(dev, pipe) && --count > 0); |
248 | |
249 | /* |
250 | * Only reinitialize corresponding vblank timestamp if high-precision query |
251 | * available and didn't fail. Otherwise reinitialize delayed at next vblank |
252 | * interrupt and assign 0 for now, to mark the vblanktimestamp as invalid. |
253 | */ |
254 | if (!rc) |
255 | t_vblank = 0; |
256 | |
257 | /* |
258 | * +1 to make sure user will never see the same |
259 | * vblank counter value before and after a modeset |
260 | */ |
261 | store_vblank(dev, pipe, vblank_count_inc: 1, t_vblank, last: cur_vblank); |
262 | |
263 | spin_unlock(lock: &dev->vblank_time_lock); |
264 | } |
265 | |
266 | /* |
267 | * Call back into the driver to update the appropriate vblank counter |
268 | * (specified by @pipe). Deal with wraparound, if it occurred, and |
269 | * update the last read value so we can deal with wraparound on the next |
270 | * call if necessary. |
271 | * |
272 | * Only necessary when going from off->on, to account for frames we |
273 | * didn't get an interrupt for. |
274 | * |
275 | * Note: caller must hold &drm_device.vbl_lock since this reads & writes |
276 | * device vblank fields. |
277 | */ |
278 | static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe, |
279 | bool in_vblank_irq) |
280 | { |
281 | struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; |
282 | u32 cur_vblank, diff; |
283 | bool rc; |
284 | ktime_t t_vblank; |
285 | int count = DRM_TIMESTAMP_MAXRETRIES; |
286 | int framedur_ns = vblank->framedur_ns; |
287 | u32 max_vblank_count = drm_max_vblank_count(dev, pipe); |
288 | |
289 | /* |
290 | * Interrupts were disabled prior to this call, so deal with counter |
291 | * wrap if needed. |
292 | * NOTE! It's possible we lost a full dev->max_vblank_count + 1 events |
293 | * here if the register is small or we had vblank interrupts off for |
294 | * a long time. |
295 | * |
296 | * We repeat the hardware vblank counter & timestamp query until |
297 | * we get consistent results. This to prevent races between gpu |
298 | * updating its hardware counter while we are retrieving the |
299 | * corresponding vblank timestamp. |
300 | */ |
301 | do { |
302 | cur_vblank = __get_vblank_counter(dev, pipe); |
303 | rc = drm_get_last_vbltimestamp(dev, pipe, tvblank: &t_vblank, in_vblank_irq); |
304 | } while (cur_vblank != __get_vblank_counter(dev, pipe) && --count > 0); |
305 | |
306 | if (max_vblank_count) { |
307 | /* trust the hw counter when it's around */ |
308 | diff = (cur_vblank - vblank->last) & max_vblank_count; |
309 | } else if (rc && framedur_ns) { |
310 | u64 diff_ns = ktime_to_ns(ktime_sub(t_vblank, vblank->time)); |
311 | |
312 | /* |
313 | * Figure out how many vblanks we've missed based |
314 | * on the difference in the timestamps and the |
315 | * frame/field duration. |
316 | */ |
317 | |
318 | drm_dbg_vbl(dev, "crtc %u: Calculating number of vblanks." |
319 | " diff_ns = %lld, framedur_ns = %d)\n" , |
320 | pipe, (long long)diff_ns, framedur_ns); |
321 | |
322 | diff = DIV_ROUND_CLOSEST_ULL(diff_ns, framedur_ns); |
323 | |
324 | if (diff == 0 && in_vblank_irq) |
325 | drm_dbg_vbl(dev, "crtc %u: Redundant vblirq ignored\n" , |
326 | pipe); |
327 | } else { |
328 | /* some kind of default for drivers w/o accurate vbl timestamping */ |
329 | diff = in_vblank_irq ? 1 : 0; |
330 | } |
331 | |
332 | /* |
333 | * Within a drm_vblank_pre_modeset - drm_vblank_post_modeset |
334 | * interval? If so then vblank irqs keep running and it will likely |
335 | * happen that the hardware vblank counter is not trustworthy as it |
336 | * might reset at some point in that interval and vblank timestamps |
337 | * are not trustworthy either in that interval. Iow. this can result |
338 | * in a bogus diff >> 1 which must be avoided as it would cause |
339 | * random large forward jumps of the software vblank counter. |
340 | */ |
341 | if (diff > 1 && (vblank->inmodeset & 0x2)) { |
342 | drm_dbg_vbl(dev, |
343 | "clamping vblank bump to 1 on crtc %u: diffr=%u" |
344 | " due to pre-modeset.\n" , pipe, diff); |
345 | diff = 1; |
346 | } |
347 | |
348 | drm_dbg_vbl(dev, "updating vblank count on crtc %u:" |
349 | " current=%llu, diff=%u, hw=%u hw_last=%u\n" , |
350 | pipe, (unsigned long long)atomic64_read(&vblank->count), |
351 | diff, cur_vblank, vblank->last); |
352 | |
353 | if (diff == 0) { |
354 | drm_WARN_ON_ONCE(dev, cur_vblank != vblank->last); |
355 | return; |
356 | } |
357 | |
358 | /* |
359 | * Only reinitialize corresponding vblank timestamp if high-precision query |
360 | * available and didn't fail, or we were called from the vblank interrupt. |
361 | * Otherwise reinitialize delayed at next vblank interrupt and assign 0 |
362 | * for now, to mark the vblanktimestamp as invalid. |
363 | */ |
364 | if (!rc && !in_vblank_irq) |
365 | t_vblank = 0; |
366 | |
367 | store_vblank(dev, pipe, vblank_count_inc: diff, t_vblank, last: cur_vblank); |
368 | } |
369 | |
370 | u64 drm_vblank_count(struct drm_device *dev, unsigned int pipe) |
371 | { |
372 | struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; |
373 | u64 count; |
374 | |
375 | if (drm_WARN_ON(dev, pipe >= dev->num_crtcs)) |
376 | return 0; |
377 | |
378 | count = atomic64_read(v: &vblank->count); |
379 | |
380 | /* |
381 | * This read barrier corresponds to the implicit write barrier of the |
382 | * write seqlock in store_vblank(). Note that this is the only place |
383 | * where we need an explicit barrier, since all other access goes |
384 | * through drm_vblank_count_and_time(), which already has the required |
385 | * read barrier curtesy of the read seqlock. |
386 | */ |
387 | smp_rmb(); |
388 | |
389 | return count; |
390 | } |
391 | |
392 | /** |
393 | * drm_crtc_accurate_vblank_count - retrieve the master vblank counter |
394 | * @crtc: which counter to retrieve |
395 | * |
396 | * This function is similar to drm_crtc_vblank_count() but this function |
397 | * interpolates to handle a race with vblank interrupts using the high precision |
398 | * timestamping support. |
399 | * |
400 | * This is mostly useful for hardware that can obtain the scanout position, but |
401 | * doesn't have a hardware frame counter. |
402 | */ |
403 | u64 drm_crtc_accurate_vblank_count(struct drm_crtc *crtc) |
404 | { |
405 | struct drm_device *dev = crtc->dev; |
406 | unsigned int pipe = drm_crtc_index(crtc); |
407 | u64 vblank; |
408 | unsigned long flags; |
409 | |
410 | drm_WARN_ONCE(dev, drm_debug_enabled(DRM_UT_VBL) && |
411 | !crtc->funcs->get_vblank_timestamp, |
412 | "This function requires support for accurate vblank timestamps." ); |
413 | |
414 | spin_lock_irqsave(&dev->vblank_time_lock, flags); |
415 | |
416 | drm_update_vblank_count(dev, pipe, in_vblank_irq: false); |
417 | vblank = drm_vblank_count(dev, pipe); |
418 | |
419 | spin_unlock_irqrestore(lock: &dev->vblank_time_lock, flags); |
420 | |
421 | return vblank; |
422 | } |
423 | EXPORT_SYMBOL(drm_crtc_accurate_vblank_count); |
424 | |
425 | static void __disable_vblank(struct drm_device *dev, unsigned int pipe) |
426 | { |
427 | if (drm_core_check_feature(dev, feature: DRIVER_MODESET)) { |
428 | struct drm_crtc *crtc = drm_crtc_from_index(dev, idx: pipe); |
429 | |
430 | if (drm_WARN_ON(dev, !crtc)) |
431 | return; |
432 | |
433 | if (crtc->funcs->disable_vblank) |
434 | crtc->funcs->disable_vblank(crtc); |
435 | } |
436 | #ifdef CONFIG_DRM_LEGACY |
437 | else { |
438 | dev->driver->disable_vblank(dev, pipe); |
439 | } |
440 | #endif |
441 | } |
442 | |
443 | /* |
444 | * Disable vblank irq's on crtc, make sure that last vblank count |
445 | * of hardware and corresponding consistent software vblank counter |
446 | * are preserved, even if there are any spurious vblank irq's after |
447 | * disable. |
448 | */ |
449 | void drm_vblank_disable_and_save(struct drm_device *dev, unsigned int pipe) |
450 | { |
451 | struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; |
452 | unsigned long irqflags; |
453 | |
454 | assert_spin_locked(&dev->vbl_lock); |
455 | |
456 | /* Prevent vblank irq processing while disabling vblank irqs, |
457 | * so no updates of timestamps or count can happen after we've |
458 | * disabled. Needed to prevent races in case of delayed irq's. |
459 | */ |
460 | spin_lock_irqsave(&dev->vblank_time_lock, irqflags); |
461 | |
462 | /* |
463 | * Update vblank count and disable vblank interrupts only if the |
464 | * interrupts were enabled. This avoids calling the ->disable_vblank() |
465 | * operation in atomic context with the hardware potentially runtime |
466 | * suspended. |
467 | */ |
468 | if (!vblank->enabled) |
469 | goto out; |
470 | |
471 | /* |
472 | * Update the count and timestamp to maintain the |
473 | * appearance that the counter has been ticking all along until |
474 | * this time. This makes the count account for the entire time |
475 | * between drm_crtc_vblank_on() and drm_crtc_vblank_off(). |
476 | */ |
477 | drm_update_vblank_count(dev, pipe, in_vblank_irq: false); |
478 | __disable_vblank(dev, pipe); |
479 | vblank->enabled = false; |
480 | |
481 | out: |
482 | spin_unlock_irqrestore(lock: &dev->vblank_time_lock, flags: irqflags); |
483 | } |
484 | |
485 | static void vblank_disable_fn(struct timer_list *t) |
486 | { |
487 | struct drm_vblank_crtc *vblank = from_timer(vblank, t, disable_timer); |
488 | struct drm_device *dev = vblank->dev; |
489 | unsigned int pipe = vblank->pipe; |
490 | unsigned long irqflags; |
491 | |
492 | spin_lock_irqsave(&dev->vbl_lock, irqflags); |
493 | if (atomic_read(v: &vblank->refcount) == 0 && vblank->enabled) { |
494 | drm_dbg_core(dev, "disabling vblank on crtc %u\n" , pipe); |
495 | drm_vblank_disable_and_save(dev, pipe); |
496 | } |
497 | spin_unlock_irqrestore(lock: &dev->vbl_lock, flags: irqflags); |
498 | } |
499 | |
500 | static void drm_vblank_init_release(struct drm_device *dev, void *ptr) |
501 | { |
502 | struct drm_vblank_crtc *vblank = ptr; |
503 | |
504 | drm_WARN_ON(dev, READ_ONCE(vblank->enabled) && |
505 | drm_core_check_feature(dev, DRIVER_MODESET)); |
506 | |
507 | drm_vblank_destroy_worker(vblank); |
508 | del_timer_sync(timer: &vblank->disable_timer); |
509 | } |
510 | |
511 | /** |
512 | * drm_vblank_init - initialize vblank support |
513 | * @dev: DRM device |
514 | * @num_crtcs: number of CRTCs supported by @dev |
515 | * |
516 | * This function initializes vblank support for @num_crtcs display pipelines. |
517 | * Cleanup is handled automatically through a cleanup function added with |
518 | * drmm_add_action_or_reset(). |
519 | * |
520 | * Returns: |
521 | * Zero on success or a negative error code on failure. |
522 | */ |
523 | int drm_vblank_init(struct drm_device *dev, unsigned int num_crtcs) |
524 | { |
525 | int ret; |
526 | unsigned int i; |
527 | |
528 | spin_lock_init(&dev->vbl_lock); |
529 | spin_lock_init(&dev->vblank_time_lock); |
530 | |
531 | dev->vblank = drmm_kcalloc(dev, n: num_crtcs, size: sizeof(*dev->vblank), GFP_KERNEL); |
532 | if (!dev->vblank) |
533 | return -ENOMEM; |
534 | |
535 | dev->num_crtcs = num_crtcs; |
536 | |
537 | for (i = 0; i < num_crtcs; i++) { |
538 | struct drm_vblank_crtc *vblank = &dev->vblank[i]; |
539 | |
540 | vblank->dev = dev; |
541 | vblank->pipe = i; |
542 | init_waitqueue_head(&vblank->queue); |
543 | timer_setup(&vblank->disable_timer, vblank_disable_fn, 0); |
544 | seqlock_init(&vblank->seqlock); |
545 | |
546 | ret = drmm_add_action_or_reset(dev, drm_vblank_init_release, |
547 | vblank); |
548 | if (ret) |
549 | return ret; |
550 | |
551 | ret = drm_vblank_worker_init(vblank); |
552 | if (ret) |
553 | return ret; |
554 | } |
555 | |
556 | return 0; |
557 | } |
558 | EXPORT_SYMBOL(drm_vblank_init); |
559 | |
560 | /** |
561 | * drm_dev_has_vblank - test if vblanking has been initialized for |
562 | * a device |
563 | * @dev: the device |
564 | * |
565 | * Drivers may call this function to test if vblank support is |
566 | * initialized for a device. For most hardware this means that vblanking |
567 | * can also be enabled. |
568 | * |
569 | * Atomic helpers use this function to initialize |
570 | * &drm_crtc_state.no_vblank. See also drm_atomic_helper_check_modeset(). |
571 | * |
572 | * Returns: |
573 | * True if vblanking has been initialized for the given device, false |
574 | * otherwise. |
575 | */ |
576 | bool drm_dev_has_vblank(const struct drm_device *dev) |
577 | { |
578 | return dev->num_crtcs != 0; |
579 | } |
580 | EXPORT_SYMBOL(drm_dev_has_vblank); |
581 | |
582 | /** |
583 | * drm_crtc_vblank_waitqueue - get vblank waitqueue for the CRTC |
584 | * @crtc: which CRTC's vblank waitqueue to retrieve |
585 | * |
586 | * This function returns a pointer to the vblank waitqueue for the CRTC. |
587 | * Drivers can use this to implement vblank waits using wait_event() and related |
588 | * functions. |
589 | */ |
590 | wait_queue_head_t *drm_crtc_vblank_waitqueue(struct drm_crtc *crtc) |
591 | { |
592 | return &crtc->dev->vblank[drm_crtc_index(crtc)].queue; |
593 | } |
594 | EXPORT_SYMBOL(drm_crtc_vblank_waitqueue); |
595 | |
596 | |
597 | /** |
598 | * drm_calc_timestamping_constants - calculate vblank timestamp constants |
599 | * @crtc: drm_crtc whose timestamp constants should be updated. |
600 | * @mode: display mode containing the scanout timings |
601 | * |
602 | * Calculate and store various constants which are later needed by vblank and |
603 | * swap-completion timestamping, e.g, by |
604 | * drm_crtc_vblank_helper_get_vblank_timestamp(). They are derived from |
605 | * CRTC's true scanout timing, so they take things like panel scaling or |
606 | * other adjustments into account. |
607 | */ |
608 | void drm_calc_timestamping_constants(struct drm_crtc *crtc, |
609 | const struct drm_display_mode *mode) |
610 | { |
611 | struct drm_device *dev = crtc->dev; |
612 | unsigned int pipe = drm_crtc_index(crtc); |
613 | struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; |
614 | int linedur_ns = 0, framedur_ns = 0; |
615 | int dotclock = mode->crtc_clock; |
616 | |
617 | if (!drm_dev_has_vblank(dev)) |
618 | return; |
619 | |
620 | if (drm_WARN_ON(dev, pipe >= dev->num_crtcs)) |
621 | return; |
622 | |
623 | /* Valid dotclock? */ |
624 | if (dotclock > 0) { |
625 | int frame_size = mode->crtc_htotal * mode->crtc_vtotal; |
626 | |
627 | /* |
628 | * Convert scanline length in pixels and video |
629 | * dot clock to line duration and frame duration |
630 | * in nanoseconds: |
631 | */ |
632 | linedur_ns = div_u64(dividend: (u64) mode->crtc_htotal * 1000000, divisor: dotclock); |
633 | framedur_ns = div_u64(dividend: (u64) frame_size * 1000000, divisor: dotclock); |
634 | |
635 | /* |
636 | * Fields of interlaced scanout modes are only half a frame duration. |
637 | */ |
638 | if (mode->flags & DRM_MODE_FLAG_INTERLACE) |
639 | framedur_ns /= 2; |
640 | } else { |
641 | drm_err(dev, "crtc %u: Can't calculate constants, dotclock = 0!\n" , |
642 | crtc->base.id); |
643 | } |
644 | |
645 | vblank->linedur_ns = linedur_ns; |
646 | vblank->framedur_ns = framedur_ns; |
647 | drm_mode_copy(dst: &vblank->hwmode, src: mode); |
648 | |
649 | drm_dbg_core(dev, |
650 | "crtc %u: hwmode: htotal %d, vtotal %d, vdisplay %d\n" , |
651 | crtc->base.id, mode->crtc_htotal, |
652 | mode->crtc_vtotal, mode->crtc_vdisplay); |
653 | drm_dbg_core(dev, "crtc %u: clock %d kHz framedur %d linedur %d\n" , |
654 | crtc->base.id, dotclock, framedur_ns, linedur_ns); |
655 | } |
656 | EXPORT_SYMBOL(drm_calc_timestamping_constants); |
657 | |
658 | /** |
659 | * drm_crtc_vblank_helper_get_vblank_timestamp_internal - precise vblank |
660 | * timestamp helper |
661 | * @crtc: CRTC whose vblank timestamp to retrieve |
662 | * @max_error: Desired maximum allowable error in timestamps (nanosecs) |
663 | * On return contains true maximum error of timestamp |
664 | * @vblank_time: Pointer to time which should receive the timestamp |
665 | * @in_vblank_irq: |
666 | * True when called from drm_crtc_handle_vblank(). Some drivers |
667 | * need to apply some workarounds for gpu-specific vblank irq quirks |
668 | * if flag is set. |
669 | * @get_scanout_position: |
670 | * Callback function to retrieve the scanout position. See |
671 | * @struct drm_crtc_helper_funcs.get_scanout_position. |
672 | * |
673 | * Implements calculation of exact vblank timestamps from given drm_display_mode |
674 | * timings and current video scanout position of a CRTC. |
675 | * |
676 | * The current implementation only handles standard video modes. For double scan |
677 | * and interlaced modes the driver is supposed to adjust the hardware mode |
678 | * (taken from &drm_crtc_state.adjusted mode for atomic modeset drivers) to |
679 | * match the scanout position reported. |
680 | * |
681 | * Note that atomic drivers must call drm_calc_timestamping_constants() before |
682 | * enabling a CRTC. The atomic helpers already take care of that in |
683 | * drm_atomic_helper_calc_timestamping_constants(). |
684 | * |
685 | * Returns: |
686 | * |
687 | * Returns true on success, and false on failure, i.e. when no accurate |
688 | * timestamp could be acquired. |
689 | */ |
690 | bool |
691 | drm_crtc_vblank_helper_get_vblank_timestamp_internal( |
692 | struct drm_crtc *crtc, int *max_error, ktime_t *vblank_time, |
693 | bool in_vblank_irq, |
694 | drm_vblank_get_scanout_position_func get_scanout_position) |
695 | { |
696 | struct drm_device *dev = crtc->dev; |
697 | unsigned int pipe = crtc->index; |
698 | struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; |
699 | struct timespec64 ts_etime, ts_vblank_time; |
700 | ktime_t stime, etime; |
701 | bool vbl_status; |
702 | const struct drm_display_mode *mode; |
703 | int vpos, hpos, i; |
704 | int delta_ns, duration_ns; |
705 | |
706 | if (pipe >= dev->num_crtcs) { |
707 | drm_err(dev, "Invalid crtc %u\n" , pipe); |
708 | return false; |
709 | } |
710 | |
711 | /* Scanout position query not supported? Should not happen. */ |
712 | if (!get_scanout_position) { |
713 | drm_err(dev, "Called from CRTC w/o get_scanout_position()!?\n" ); |
714 | return false; |
715 | } |
716 | |
717 | if (drm_drv_uses_atomic_modeset(dev)) |
718 | mode = &vblank->hwmode; |
719 | else |
720 | mode = &crtc->hwmode; |
721 | |
722 | /* If mode timing undefined, just return as no-op: |
723 | * Happens during initial modesetting of a crtc. |
724 | */ |
725 | if (mode->crtc_clock == 0) { |
726 | drm_dbg_core(dev, "crtc %u: Noop due to uninitialized mode.\n" , |
727 | pipe); |
728 | drm_WARN_ON_ONCE(dev, drm_drv_uses_atomic_modeset(dev)); |
729 | return false; |
730 | } |
731 | |
732 | /* Get current scanout position with system timestamp. |
733 | * Repeat query up to DRM_TIMESTAMP_MAXRETRIES times |
734 | * if single query takes longer than max_error nanoseconds. |
735 | * |
736 | * This guarantees a tight bound on maximum error if |
737 | * code gets preempted or delayed for some reason. |
738 | */ |
739 | for (i = 0; i < DRM_TIMESTAMP_MAXRETRIES; i++) { |
740 | /* |
741 | * Get vertical and horizontal scanout position vpos, hpos, |
742 | * and bounding timestamps stime, etime, pre/post query. |
743 | */ |
744 | vbl_status = get_scanout_position(crtc, in_vblank_irq, |
745 | &vpos, &hpos, |
746 | &stime, &etime, |
747 | mode); |
748 | |
749 | /* Return as no-op if scanout query unsupported or failed. */ |
750 | if (!vbl_status) { |
751 | drm_dbg_core(dev, |
752 | "crtc %u : scanoutpos query failed.\n" , |
753 | pipe); |
754 | return false; |
755 | } |
756 | |
757 | /* Compute uncertainty in timestamp of scanout position query. */ |
758 | duration_ns = ktime_to_ns(kt: etime) - ktime_to_ns(kt: stime); |
759 | |
760 | /* Accept result with < max_error nsecs timing uncertainty. */ |
761 | if (duration_ns <= *max_error) |
762 | break; |
763 | } |
764 | |
765 | /* Noisy system timing? */ |
766 | if (i == DRM_TIMESTAMP_MAXRETRIES) { |
767 | drm_dbg_core(dev, |
768 | "crtc %u: Noisy timestamp %d us > %d us [%d reps].\n" , |
769 | pipe, duration_ns / 1000, *max_error / 1000, i); |
770 | } |
771 | |
772 | /* Return upper bound of timestamp precision error. */ |
773 | *max_error = duration_ns; |
774 | |
775 | /* Convert scanout position into elapsed time at raw_time query |
776 | * since start of scanout at first display scanline. delta_ns |
777 | * can be negative if start of scanout hasn't happened yet. |
778 | */ |
779 | delta_ns = div_s64(dividend: 1000000LL * (vpos * mode->crtc_htotal + hpos), |
780 | divisor: mode->crtc_clock); |
781 | |
782 | /* Subtract time delta from raw timestamp to get final |
783 | * vblank_time timestamp for end of vblank. |
784 | */ |
785 | *vblank_time = ktime_sub_ns(etime, delta_ns); |
786 | |
787 | if (!drm_debug_enabled(DRM_UT_VBL)) |
788 | return true; |
789 | |
790 | ts_etime = ktime_to_timespec64(etime); |
791 | ts_vblank_time = ktime_to_timespec64(*vblank_time); |
792 | |
793 | drm_dbg_vbl(dev, |
794 | "crtc %u : v p(%d,%d)@ %lld.%06ld -> %lld.%06ld [e %d us, %d rep]\n" , |
795 | pipe, hpos, vpos, |
796 | (u64)ts_etime.tv_sec, ts_etime.tv_nsec / 1000, |
797 | (u64)ts_vblank_time.tv_sec, ts_vblank_time.tv_nsec / 1000, |
798 | duration_ns / 1000, i); |
799 | |
800 | return true; |
801 | } |
802 | EXPORT_SYMBOL(drm_crtc_vblank_helper_get_vblank_timestamp_internal); |
803 | |
804 | /** |
805 | * drm_crtc_vblank_helper_get_vblank_timestamp - precise vblank timestamp |
806 | * helper |
807 | * @crtc: CRTC whose vblank timestamp to retrieve |
808 | * @max_error: Desired maximum allowable error in timestamps (nanosecs) |
809 | * On return contains true maximum error of timestamp |
810 | * @vblank_time: Pointer to time which should receive the timestamp |
811 | * @in_vblank_irq: |
812 | * True when called from drm_crtc_handle_vblank(). Some drivers |
813 | * need to apply some workarounds for gpu-specific vblank irq quirks |
814 | * if flag is set. |
815 | * |
816 | * Implements calculation of exact vblank timestamps from given drm_display_mode |
817 | * timings and current video scanout position of a CRTC. This can be directly |
818 | * used as the &drm_crtc_funcs.get_vblank_timestamp implementation of a kms |
819 | * driver if &drm_crtc_helper_funcs.get_scanout_position is implemented. |
820 | * |
821 | * The current implementation only handles standard video modes. For double scan |
822 | * and interlaced modes the driver is supposed to adjust the hardware mode |
823 | * (taken from &drm_crtc_state.adjusted mode for atomic modeset drivers) to |
824 | * match the scanout position reported. |
825 | * |
826 | * Note that atomic drivers must call drm_calc_timestamping_constants() before |
827 | * enabling a CRTC. The atomic helpers already take care of that in |
828 | * drm_atomic_helper_calc_timestamping_constants(). |
829 | * |
830 | * Returns: |
831 | * |
832 | * Returns true on success, and false on failure, i.e. when no accurate |
833 | * timestamp could be acquired. |
834 | */ |
835 | bool drm_crtc_vblank_helper_get_vblank_timestamp(struct drm_crtc *crtc, |
836 | int *max_error, |
837 | ktime_t *vblank_time, |
838 | bool in_vblank_irq) |
839 | { |
840 | return drm_crtc_vblank_helper_get_vblank_timestamp_internal( |
841 | crtc, max_error, vblank_time, in_vblank_irq, |
842 | crtc->helper_private->get_scanout_position); |
843 | } |
844 | EXPORT_SYMBOL(drm_crtc_vblank_helper_get_vblank_timestamp); |
845 | |
846 | /** |
847 | * drm_crtc_get_last_vbltimestamp - retrieve raw timestamp for the most |
848 | * recent vblank interval |
849 | * @crtc: CRTC whose vblank timestamp to retrieve |
850 | * @tvblank: Pointer to target time which should receive the timestamp |
851 | * @in_vblank_irq: |
852 | * True when called from drm_crtc_handle_vblank(). Some drivers |
853 | * need to apply some workarounds for gpu-specific vblank irq quirks |
854 | * if flag is set. |
855 | * |
856 | * Fetches the system timestamp corresponding to the time of the most recent |
857 | * vblank interval on specified CRTC. May call into kms-driver to |
858 | * compute the timestamp with a high-precision GPU specific method. |
859 | * |
860 | * Returns zero if timestamp originates from uncorrected do_gettimeofday() |
861 | * call, i.e., it isn't very precisely locked to the true vblank. |
862 | * |
863 | * Returns: |
864 | * True if timestamp is considered to be very precise, false otherwise. |
865 | */ |
866 | static bool |
867 | drm_crtc_get_last_vbltimestamp(struct drm_crtc *crtc, ktime_t *tvblank, |
868 | bool in_vblank_irq) |
869 | { |
870 | bool ret = false; |
871 | |
872 | /* Define requested maximum error on timestamps (nanoseconds). */ |
873 | int max_error = (int) drm_timestamp_precision * 1000; |
874 | |
875 | /* Query driver if possible and precision timestamping enabled. */ |
876 | if (crtc && crtc->funcs->get_vblank_timestamp && max_error > 0) { |
877 | ret = crtc->funcs->get_vblank_timestamp(crtc, &max_error, |
878 | tvblank, in_vblank_irq); |
879 | } |
880 | |
881 | /* GPU high precision timestamp query unsupported or failed. |
882 | * Return current monotonic/gettimeofday timestamp as best estimate. |
883 | */ |
884 | if (!ret) |
885 | *tvblank = ktime_get(); |
886 | |
887 | return ret; |
888 | } |
889 | |
890 | static bool |
891 | drm_get_last_vbltimestamp(struct drm_device *dev, unsigned int pipe, |
892 | ktime_t *tvblank, bool in_vblank_irq) |
893 | { |
894 | struct drm_crtc *crtc = drm_crtc_from_index(dev, idx: pipe); |
895 | |
896 | return drm_crtc_get_last_vbltimestamp(crtc, tvblank, in_vblank_irq); |
897 | } |
898 | |
899 | /** |
900 | * drm_crtc_vblank_count - retrieve "cooked" vblank counter value |
901 | * @crtc: which counter to retrieve |
902 | * |
903 | * Fetches the "cooked" vblank count value that represents the number of |
904 | * vblank events since the system was booted, including lost events due to |
905 | * modesetting activity. Note that this timer isn't correct against a racing |
906 | * vblank interrupt (since it only reports the software vblank counter), see |
907 | * drm_crtc_accurate_vblank_count() for such use-cases. |
908 | * |
909 | * Note that for a given vblank counter value drm_crtc_handle_vblank() |
910 | * and drm_crtc_vblank_count() or drm_crtc_vblank_count_and_time() |
911 | * provide a barrier: Any writes done before calling |
912 | * drm_crtc_handle_vblank() will be visible to callers of the later |
913 | * functions, if the vblank count is the same or a later one. |
914 | * |
915 | * See also &drm_vblank_crtc.count. |
916 | * |
917 | * Returns: |
918 | * The software vblank counter. |
919 | */ |
920 | u64 drm_crtc_vblank_count(struct drm_crtc *crtc) |
921 | { |
922 | return drm_vblank_count(dev: crtc->dev, pipe: drm_crtc_index(crtc)); |
923 | } |
924 | EXPORT_SYMBOL(drm_crtc_vblank_count); |
925 | |
926 | /** |
927 | * drm_vblank_count_and_time - retrieve "cooked" vblank counter value and the |
928 | * system timestamp corresponding to that vblank counter value. |
929 | * @dev: DRM device |
930 | * @pipe: index of CRTC whose counter to retrieve |
931 | * @vblanktime: Pointer to ktime_t to receive the vblank timestamp. |
932 | * |
933 | * Fetches the "cooked" vblank count value that represents the number of |
934 | * vblank events since the system was booted, including lost events due to |
935 | * modesetting activity. Returns corresponding system timestamp of the time |
936 | * of the vblank interval that corresponds to the current vblank counter value. |
937 | * |
938 | * This is the legacy version of drm_crtc_vblank_count_and_time(). |
939 | */ |
940 | static u64 drm_vblank_count_and_time(struct drm_device *dev, unsigned int pipe, |
941 | ktime_t *vblanktime) |
942 | { |
943 | struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; |
944 | u64 vblank_count; |
945 | unsigned int seq; |
946 | |
947 | if (drm_WARN_ON(dev, pipe >= dev->num_crtcs)) { |
948 | *vblanktime = 0; |
949 | return 0; |
950 | } |
951 | |
952 | do { |
953 | seq = read_seqbegin(sl: &vblank->seqlock); |
954 | vblank_count = atomic64_read(v: &vblank->count); |
955 | *vblanktime = vblank->time; |
956 | } while (read_seqretry(sl: &vblank->seqlock, start: seq)); |
957 | |
958 | return vblank_count; |
959 | } |
960 | |
961 | /** |
962 | * drm_crtc_vblank_count_and_time - retrieve "cooked" vblank counter value |
963 | * and the system timestamp corresponding to that vblank counter value |
964 | * @crtc: which counter to retrieve |
965 | * @vblanktime: Pointer to time to receive the vblank timestamp. |
966 | * |
967 | * Fetches the "cooked" vblank count value that represents the number of |
968 | * vblank events since the system was booted, including lost events due to |
969 | * modesetting activity. Returns corresponding system timestamp of the time |
970 | * of the vblank interval that corresponds to the current vblank counter value. |
971 | * |
972 | * Note that for a given vblank counter value drm_crtc_handle_vblank() |
973 | * and drm_crtc_vblank_count() or drm_crtc_vblank_count_and_time() |
974 | * provide a barrier: Any writes done before calling |
975 | * drm_crtc_handle_vblank() will be visible to callers of the later |
976 | * functions, if the vblank count is the same or a later one. |
977 | * |
978 | * See also &drm_vblank_crtc.count. |
979 | */ |
980 | u64 drm_crtc_vblank_count_and_time(struct drm_crtc *crtc, |
981 | ktime_t *vblanktime) |
982 | { |
983 | return drm_vblank_count_and_time(dev: crtc->dev, pipe: drm_crtc_index(crtc), |
984 | vblanktime); |
985 | } |
986 | EXPORT_SYMBOL(drm_crtc_vblank_count_and_time); |
987 | |
988 | /** |
989 | * drm_crtc_next_vblank_start - calculate the time of the next vblank |
990 | * @crtc: the crtc for which to calculate next vblank time |
991 | * @vblanktime: pointer to time to receive the next vblank timestamp. |
992 | * |
993 | * Calculate the expected time of the start of the next vblank period, |
994 | * based on time of previous vblank and frame duration |
995 | */ |
996 | int drm_crtc_next_vblank_start(struct drm_crtc *crtc, ktime_t *vblanktime) |
997 | { |
998 | unsigned int pipe = drm_crtc_index(crtc); |
999 | struct drm_vblank_crtc *vblank; |
1000 | struct drm_display_mode *mode; |
1001 | u64 vblank_start; |
1002 | |
1003 | if (!drm_dev_has_vblank(crtc->dev)) |
1004 | return -EINVAL; |
1005 | |
1006 | vblank = &crtc->dev->vblank[pipe]; |
1007 | mode = &vblank->hwmode; |
1008 | |
1009 | if (!vblank->framedur_ns || !vblank->linedur_ns) |
1010 | return -EINVAL; |
1011 | |
1012 | if (!drm_crtc_get_last_vbltimestamp(crtc, tvblank: vblanktime, in_vblank_irq: false)) |
1013 | return -EINVAL; |
1014 | |
1015 | vblank_start = DIV_ROUND_DOWN_ULL( |
1016 | (u64)vblank->framedur_ns * mode->crtc_vblank_start, |
1017 | mode->crtc_vtotal); |
1018 | *vblanktime = ktime_add(*vblanktime, ns_to_ktime(vblank_start)); |
1019 | |
1020 | return 0; |
1021 | } |
1022 | EXPORT_SYMBOL(drm_crtc_next_vblank_start); |
1023 | |
1024 | static void send_vblank_event(struct drm_device *dev, |
1025 | struct drm_pending_vblank_event *e, |
1026 | u64 seq, ktime_t now) |
1027 | { |
1028 | struct timespec64 tv; |
1029 | |
1030 | switch (e->event.base.type) { |
1031 | case DRM_EVENT_VBLANK: |
1032 | case DRM_EVENT_FLIP_COMPLETE: |
1033 | tv = ktime_to_timespec64(now); |
1034 | e->event.vbl.sequence = seq; |
1035 | /* |
1036 | * e->event is a user space structure, with hardcoded unsigned |
1037 | * 32-bit seconds/microseconds. This is safe as we always use |
1038 | * monotonic timestamps since linux-4.15 |
1039 | */ |
1040 | e->event.vbl.tv_sec = tv.tv_sec; |
1041 | e->event.vbl.tv_usec = tv.tv_nsec / 1000; |
1042 | break; |
1043 | case DRM_EVENT_CRTC_SEQUENCE: |
1044 | if (seq) |
1045 | e->event.seq.sequence = seq; |
1046 | e->event.seq.time_ns = ktime_to_ns(kt: now); |
1047 | break; |
1048 | } |
1049 | trace_drm_vblank_event_delivered(file: e->base.file_priv, crtc: e->pipe, seq); |
1050 | /* |
1051 | * Use the same timestamp for any associated fence signal to avoid |
1052 | * mismatch in timestamps for vsync & fence events triggered by the |
1053 | * same HW event. Frameworks like SurfaceFlinger in Android expects the |
1054 | * retire-fence timestamp to match exactly with HW vsync as it uses it |
1055 | * for its software vsync modeling. |
1056 | */ |
1057 | drm_send_event_timestamp_locked(dev, e: &e->base, timestamp: now); |
1058 | } |
1059 | |
1060 | /** |
1061 | * drm_crtc_arm_vblank_event - arm vblank event after pageflip |
1062 | * @crtc: the source CRTC of the vblank event |
1063 | * @e: the event to send |
1064 | * |
1065 | * A lot of drivers need to generate vblank events for the very next vblank |
1066 | * interrupt. For example when the page flip interrupt happens when the page |
1067 | * flip gets armed, but not when it actually executes within the next vblank |
1068 | * period. This helper function implements exactly the required vblank arming |
1069 | * behaviour. |
1070 | * |
1071 | * NOTE: Drivers using this to send out the &drm_crtc_state.event as part of an |
1072 | * atomic commit must ensure that the next vblank happens at exactly the same |
1073 | * time as the atomic commit is committed to the hardware. This function itself |
1074 | * does **not** protect against the next vblank interrupt racing with either this |
1075 | * function call or the atomic commit operation. A possible sequence could be: |
1076 | * |
1077 | * 1. Driver commits new hardware state into vblank-synchronized registers. |
1078 | * 2. A vblank happens, committing the hardware state. Also the corresponding |
1079 | * vblank interrupt is fired off and fully processed by the interrupt |
1080 | * handler. |
1081 | * 3. The atomic commit operation proceeds to call drm_crtc_arm_vblank_event(). |
1082 | * 4. The event is only send out for the next vblank, which is wrong. |
1083 | * |
1084 | * An equivalent race can happen when the driver calls |
1085 | * drm_crtc_arm_vblank_event() before writing out the new hardware state. |
1086 | * |
1087 | * The only way to make this work safely is to prevent the vblank from firing |
1088 | * (and the hardware from committing anything else) until the entire atomic |
1089 | * commit sequence has run to completion. If the hardware does not have such a |
1090 | * feature (e.g. using a "go" bit), then it is unsafe to use this functions. |
1091 | * Instead drivers need to manually send out the event from their interrupt |
1092 | * handler by calling drm_crtc_send_vblank_event() and make sure that there's no |
1093 | * possible race with the hardware committing the atomic update. |
1094 | * |
1095 | * Caller must hold a vblank reference for the event @e acquired by a |
1096 | * drm_crtc_vblank_get(), which will be dropped when the next vblank arrives. |
1097 | */ |
1098 | void drm_crtc_arm_vblank_event(struct drm_crtc *crtc, |
1099 | struct drm_pending_vblank_event *e) |
1100 | { |
1101 | struct drm_device *dev = crtc->dev; |
1102 | unsigned int pipe = drm_crtc_index(crtc); |
1103 | |
1104 | assert_spin_locked(&dev->event_lock); |
1105 | |
1106 | e->pipe = pipe; |
1107 | e->sequence = drm_crtc_accurate_vblank_count(crtc) + 1; |
1108 | list_add_tail(new: &e->base.link, head: &dev->vblank_event_list); |
1109 | } |
1110 | EXPORT_SYMBOL(drm_crtc_arm_vblank_event); |
1111 | |
1112 | /** |
1113 | * drm_crtc_send_vblank_event - helper to send vblank event after pageflip |
1114 | * @crtc: the source CRTC of the vblank event |
1115 | * @e: the event to send |
1116 | * |
1117 | * Updates sequence # and timestamp on event for the most recently processed |
1118 | * vblank, and sends it to userspace. Caller must hold event lock. |
1119 | * |
1120 | * See drm_crtc_arm_vblank_event() for a helper which can be used in certain |
1121 | * situation, especially to send out events for atomic commit operations. |
1122 | */ |
1123 | void drm_crtc_send_vblank_event(struct drm_crtc *crtc, |
1124 | struct drm_pending_vblank_event *e) |
1125 | { |
1126 | struct drm_device *dev = crtc->dev; |
1127 | u64 seq; |
1128 | unsigned int pipe = drm_crtc_index(crtc); |
1129 | ktime_t now; |
1130 | |
1131 | if (drm_dev_has_vblank(dev)) { |
1132 | seq = drm_vblank_count_and_time(dev, pipe, vblanktime: &now); |
1133 | } else { |
1134 | seq = 0; |
1135 | |
1136 | now = ktime_get(); |
1137 | } |
1138 | e->pipe = pipe; |
1139 | send_vblank_event(dev, e, seq, now); |
1140 | } |
1141 | EXPORT_SYMBOL(drm_crtc_send_vblank_event); |
1142 | |
1143 | static int __enable_vblank(struct drm_device *dev, unsigned int pipe) |
1144 | { |
1145 | if (drm_core_check_feature(dev, feature: DRIVER_MODESET)) { |
1146 | struct drm_crtc *crtc = drm_crtc_from_index(dev, idx: pipe); |
1147 | |
1148 | if (drm_WARN_ON(dev, !crtc)) |
1149 | return 0; |
1150 | |
1151 | if (crtc->funcs->enable_vblank) |
1152 | return crtc->funcs->enable_vblank(crtc); |
1153 | } |
1154 | #ifdef CONFIG_DRM_LEGACY |
1155 | else if (dev->driver->enable_vblank) { |
1156 | return dev->driver->enable_vblank(dev, pipe); |
1157 | } |
1158 | #endif |
1159 | |
1160 | return -EINVAL; |
1161 | } |
1162 | |
1163 | static int drm_vblank_enable(struct drm_device *dev, unsigned int pipe) |
1164 | { |
1165 | struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; |
1166 | int ret = 0; |
1167 | |
1168 | assert_spin_locked(&dev->vbl_lock); |
1169 | |
1170 | spin_lock(lock: &dev->vblank_time_lock); |
1171 | |
1172 | if (!vblank->enabled) { |
1173 | /* |
1174 | * Enable vblank irqs under vblank_time_lock protection. |
1175 | * All vblank count & timestamp updates are held off |
1176 | * until we are done reinitializing master counter and |
1177 | * timestamps. Filtercode in drm_handle_vblank() will |
1178 | * prevent double-accounting of same vblank interval. |
1179 | */ |
1180 | ret = __enable_vblank(dev, pipe); |
1181 | drm_dbg_core(dev, "enabling vblank on crtc %u, ret: %d\n" , |
1182 | pipe, ret); |
1183 | if (ret) { |
1184 | atomic_dec(v: &vblank->refcount); |
1185 | } else { |
1186 | drm_update_vblank_count(dev, pipe, in_vblank_irq: 0); |
1187 | /* drm_update_vblank_count() includes a wmb so we just |
1188 | * need to ensure that the compiler emits the write |
1189 | * to mark the vblank as enabled after the call |
1190 | * to drm_update_vblank_count(). |
1191 | */ |
1192 | WRITE_ONCE(vblank->enabled, true); |
1193 | } |
1194 | } |
1195 | |
1196 | spin_unlock(lock: &dev->vblank_time_lock); |
1197 | |
1198 | return ret; |
1199 | } |
1200 | |
1201 | int drm_vblank_get(struct drm_device *dev, unsigned int pipe) |
1202 | { |
1203 | struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; |
1204 | unsigned long irqflags; |
1205 | int ret = 0; |
1206 | |
1207 | if (!drm_dev_has_vblank(dev)) |
1208 | return -EINVAL; |
1209 | |
1210 | if (drm_WARN_ON(dev, pipe >= dev->num_crtcs)) |
1211 | return -EINVAL; |
1212 | |
1213 | spin_lock_irqsave(&dev->vbl_lock, irqflags); |
1214 | /* Going from 0->1 means we have to enable interrupts again */ |
1215 | if (atomic_add_return(i: 1, v: &vblank->refcount) == 1) { |
1216 | ret = drm_vblank_enable(dev, pipe); |
1217 | } else { |
1218 | if (!vblank->enabled) { |
1219 | atomic_dec(v: &vblank->refcount); |
1220 | ret = -EINVAL; |
1221 | } |
1222 | } |
1223 | spin_unlock_irqrestore(lock: &dev->vbl_lock, flags: irqflags); |
1224 | |
1225 | return ret; |
1226 | } |
1227 | |
1228 | /** |
1229 | * drm_crtc_vblank_get - get a reference count on vblank events |
1230 | * @crtc: which CRTC to own |
1231 | * |
1232 | * Acquire a reference count on vblank events to avoid having them disabled |
1233 | * while in use. |
1234 | * |
1235 | * Returns: |
1236 | * Zero on success or a negative error code on failure. |
1237 | */ |
1238 | int drm_crtc_vblank_get(struct drm_crtc *crtc) |
1239 | { |
1240 | return drm_vblank_get(dev: crtc->dev, pipe: drm_crtc_index(crtc)); |
1241 | } |
1242 | EXPORT_SYMBOL(drm_crtc_vblank_get); |
1243 | |
1244 | void drm_vblank_put(struct drm_device *dev, unsigned int pipe) |
1245 | { |
1246 | struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; |
1247 | |
1248 | if (drm_WARN_ON(dev, pipe >= dev->num_crtcs)) |
1249 | return; |
1250 | |
1251 | if (drm_WARN_ON(dev, atomic_read(&vblank->refcount) == 0)) |
1252 | return; |
1253 | |
1254 | /* Last user schedules interrupt disable */ |
1255 | if (atomic_dec_and_test(v: &vblank->refcount)) { |
1256 | if (drm_vblank_offdelay == 0) |
1257 | return; |
1258 | else if (drm_vblank_offdelay < 0) |
1259 | vblank_disable_fn(t: &vblank->disable_timer); |
1260 | else if (!dev->vblank_disable_immediate) |
1261 | mod_timer(timer: &vblank->disable_timer, |
1262 | expires: jiffies + ((drm_vblank_offdelay * HZ)/1000)); |
1263 | } |
1264 | } |
1265 | |
1266 | /** |
1267 | * drm_crtc_vblank_put - give up ownership of vblank events |
1268 | * @crtc: which counter to give up |
1269 | * |
1270 | * Release ownership of a given vblank counter, turning off interrupts |
1271 | * if possible. Disable interrupts after drm_vblank_offdelay milliseconds. |
1272 | */ |
1273 | void drm_crtc_vblank_put(struct drm_crtc *crtc) |
1274 | { |
1275 | drm_vblank_put(dev: crtc->dev, pipe: drm_crtc_index(crtc)); |
1276 | } |
1277 | EXPORT_SYMBOL(drm_crtc_vblank_put); |
1278 | |
1279 | /** |
1280 | * drm_wait_one_vblank - wait for one vblank |
1281 | * @dev: DRM device |
1282 | * @pipe: CRTC index |
1283 | * |
1284 | * This waits for one vblank to pass on @pipe, using the irq driver interfaces. |
1285 | * It is a failure to call this when the vblank irq for @pipe is disabled, e.g. |
1286 | * due to lack of driver support or because the crtc is off. |
1287 | * |
1288 | * This is the legacy version of drm_crtc_wait_one_vblank(). |
1289 | */ |
1290 | void drm_wait_one_vblank(struct drm_device *dev, unsigned int pipe) |
1291 | { |
1292 | struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; |
1293 | int ret; |
1294 | u64 last; |
1295 | |
1296 | if (drm_WARN_ON(dev, pipe >= dev->num_crtcs)) |
1297 | return; |
1298 | |
1299 | ret = drm_vblank_get(dev, pipe); |
1300 | if (drm_WARN(dev, ret, "vblank not available on crtc %i, ret=%i\n" , |
1301 | pipe, ret)) |
1302 | return; |
1303 | |
1304 | last = drm_vblank_count(dev, pipe); |
1305 | |
1306 | ret = wait_event_timeout(vblank->queue, |
1307 | last != drm_vblank_count(dev, pipe), |
1308 | msecs_to_jiffies(100)); |
1309 | |
1310 | drm_WARN(dev, ret == 0, "vblank wait timed out on crtc %i\n" , pipe); |
1311 | |
1312 | drm_vblank_put(dev, pipe); |
1313 | } |
1314 | EXPORT_SYMBOL(drm_wait_one_vblank); |
1315 | |
1316 | /** |
1317 | * drm_crtc_wait_one_vblank - wait for one vblank |
1318 | * @crtc: DRM crtc |
1319 | * |
1320 | * This waits for one vblank to pass on @crtc, using the irq driver interfaces. |
1321 | * It is a failure to call this when the vblank irq for @crtc is disabled, e.g. |
1322 | * due to lack of driver support or because the crtc is off. |
1323 | */ |
1324 | void drm_crtc_wait_one_vblank(struct drm_crtc *crtc) |
1325 | { |
1326 | drm_wait_one_vblank(crtc->dev, drm_crtc_index(crtc)); |
1327 | } |
1328 | EXPORT_SYMBOL(drm_crtc_wait_one_vblank); |
1329 | |
1330 | /** |
1331 | * drm_crtc_vblank_off - disable vblank events on a CRTC |
1332 | * @crtc: CRTC in question |
1333 | * |
1334 | * Drivers can use this function to shut down the vblank interrupt handling when |
1335 | * disabling a crtc. This function ensures that the latest vblank frame count is |
1336 | * stored so that drm_vblank_on can restore it again. |
1337 | * |
1338 | * Drivers must use this function when the hardware vblank counter can get |
1339 | * reset, e.g. when suspending or disabling the @crtc in general. |
1340 | */ |
1341 | void drm_crtc_vblank_off(struct drm_crtc *crtc) |
1342 | { |
1343 | struct drm_device *dev = crtc->dev; |
1344 | unsigned int pipe = drm_crtc_index(crtc); |
1345 | struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; |
1346 | struct drm_pending_vblank_event *e, *t; |
1347 | ktime_t now; |
1348 | u64 seq; |
1349 | |
1350 | if (drm_WARN_ON(dev, pipe >= dev->num_crtcs)) |
1351 | return; |
1352 | |
1353 | /* |
1354 | * Grab event_lock early to prevent vblank work from being scheduled |
1355 | * while we're in the middle of shutting down vblank interrupts |
1356 | */ |
1357 | spin_lock_irq(lock: &dev->event_lock); |
1358 | |
1359 | spin_lock(lock: &dev->vbl_lock); |
1360 | drm_dbg_vbl(dev, "crtc %d, vblank enabled %d, inmodeset %d\n" , |
1361 | pipe, vblank->enabled, vblank->inmodeset); |
1362 | |
1363 | /* Avoid redundant vblank disables without previous |
1364 | * drm_crtc_vblank_on(). */ |
1365 | if (drm_core_check_feature(dev, feature: DRIVER_ATOMIC) || !vblank->inmodeset) |
1366 | drm_vblank_disable_and_save(dev, pipe); |
1367 | |
1368 | wake_up(&vblank->queue); |
1369 | |
1370 | /* |
1371 | * Prevent subsequent drm_vblank_get() from re-enabling |
1372 | * the vblank interrupt by bumping the refcount. |
1373 | */ |
1374 | if (!vblank->inmodeset) { |
1375 | atomic_inc(v: &vblank->refcount); |
1376 | vblank->inmodeset = 1; |
1377 | } |
1378 | spin_unlock(lock: &dev->vbl_lock); |
1379 | |
1380 | /* Send any queued vblank events, lest the natives grow disquiet */ |
1381 | seq = drm_vblank_count_and_time(dev, pipe, vblanktime: &now); |
1382 | |
1383 | list_for_each_entry_safe(e, t, &dev->vblank_event_list, base.link) { |
1384 | if (e->pipe != pipe) |
1385 | continue; |
1386 | drm_dbg_core(dev, "Sending premature vblank event on disable: " |
1387 | "wanted %llu, current %llu\n" , |
1388 | e->sequence, seq); |
1389 | list_del(entry: &e->base.link); |
1390 | drm_vblank_put(dev, pipe); |
1391 | send_vblank_event(dev, e, seq, now); |
1392 | } |
1393 | |
1394 | /* Cancel any leftover pending vblank work */ |
1395 | drm_vblank_cancel_pending_works(vblank); |
1396 | |
1397 | spin_unlock_irq(lock: &dev->event_lock); |
1398 | |
1399 | /* Will be reset by the modeset helpers when re-enabling the crtc by |
1400 | * calling drm_calc_timestamping_constants(). */ |
1401 | vblank->hwmode.crtc_clock = 0; |
1402 | |
1403 | /* Wait for any vblank work that's still executing to finish */ |
1404 | drm_vblank_flush_worker(vblank); |
1405 | } |
1406 | EXPORT_SYMBOL(drm_crtc_vblank_off); |
1407 | |
1408 | /** |
1409 | * drm_crtc_vblank_reset - reset vblank state to off on a CRTC |
1410 | * @crtc: CRTC in question |
1411 | * |
1412 | * Drivers can use this function to reset the vblank state to off at load time. |
1413 | * Drivers should use this together with the drm_crtc_vblank_off() and |
1414 | * drm_crtc_vblank_on() functions. The difference compared to |
1415 | * drm_crtc_vblank_off() is that this function doesn't save the vblank counter |
1416 | * and hence doesn't need to call any driver hooks. |
1417 | * |
1418 | * This is useful for recovering driver state e.g. on driver load, or on resume. |
1419 | */ |
1420 | void drm_crtc_vblank_reset(struct drm_crtc *crtc) |
1421 | { |
1422 | struct drm_device *dev = crtc->dev; |
1423 | unsigned int pipe = drm_crtc_index(crtc); |
1424 | struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; |
1425 | |
1426 | spin_lock_irq(lock: &dev->vbl_lock); |
1427 | /* |
1428 | * Prevent subsequent drm_vblank_get() from enabling the vblank |
1429 | * interrupt by bumping the refcount. |
1430 | */ |
1431 | if (!vblank->inmodeset) { |
1432 | atomic_inc(v: &vblank->refcount); |
1433 | vblank->inmodeset = 1; |
1434 | } |
1435 | spin_unlock_irq(lock: &dev->vbl_lock); |
1436 | |
1437 | drm_WARN_ON(dev, !list_empty(&dev->vblank_event_list)); |
1438 | drm_WARN_ON(dev, !list_empty(&vblank->pending_work)); |
1439 | } |
1440 | EXPORT_SYMBOL(drm_crtc_vblank_reset); |
1441 | |
1442 | /** |
1443 | * drm_crtc_set_max_vblank_count - configure the hw max vblank counter value |
1444 | * @crtc: CRTC in question |
1445 | * @max_vblank_count: max hardware vblank counter value |
1446 | * |
1447 | * Update the maximum hardware vblank counter value for @crtc |
1448 | * at runtime. Useful for hardware where the operation of the |
1449 | * hardware vblank counter depends on the currently active |
1450 | * display configuration. |
1451 | * |
1452 | * For example, if the hardware vblank counter does not work |
1453 | * when a specific connector is active the maximum can be set |
1454 | * to zero. And when that specific connector isn't active the |
1455 | * maximum can again be set to the appropriate non-zero value. |
1456 | * |
1457 | * If used, must be called before drm_vblank_on(). |
1458 | */ |
1459 | void drm_crtc_set_max_vblank_count(struct drm_crtc *crtc, |
1460 | u32 max_vblank_count) |
1461 | { |
1462 | struct drm_device *dev = crtc->dev; |
1463 | unsigned int pipe = drm_crtc_index(crtc); |
1464 | struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; |
1465 | |
1466 | drm_WARN_ON(dev, dev->max_vblank_count); |
1467 | drm_WARN_ON(dev, !READ_ONCE(vblank->inmodeset)); |
1468 | |
1469 | vblank->max_vblank_count = max_vblank_count; |
1470 | } |
1471 | EXPORT_SYMBOL(drm_crtc_set_max_vblank_count); |
1472 | |
1473 | /** |
1474 | * drm_crtc_vblank_on - enable vblank events on a CRTC |
1475 | * @crtc: CRTC in question |
1476 | * |
1477 | * This functions restores the vblank interrupt state captured with |
1478 | * drm_crtc_vblank_off() again and is generally called when enabling @crtc. Note |
1479 | * that calls to drm_crtc_vblank_on() and drm_crtc_vblank_off() can be |
1480 | * unbalanced and so can also be unconditionally called in driver load code to |
1481 | * reflect the current hardware state of the crtc. |
1482 | */ |
1483 | void drm_crtc_vblank_on(struct drm_crtc *crtc) |
1484 | { |
1485 | struct drm_device *dev = crtc->dev; |
1486 | unsigned int pipe = drm_crtc_index(crtc); |
1487 | struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; |
1488 | |
1489 | if (drm_WARN_ON(dev, pipe >= dev->num_crtcs)) |
1490 | return; |
1491 | |
1492 | spin_lock_irq(lock: &dev->vbl_lock); |
1493 | drm_dbg_vbl(dev, "crtc %d, vblank enabled %d, inmodeset %d\n" , |
1494 | pipe, vblank->enabled, vblank->inmodeset); |
1495 | |
1496 | /* Drop our private "prevent drm_vblank_get" refcount */ |
1497 | if (vblank->inmodeset) { |
1498 | atomic_dec(v: &vblank->refcount); |
1499 | vblank->inmodeset = 0; |
1500 | } |
1501 | |
1502 | drm_reset_vblank_timestamp(dev, pipe); |
1503 | |
1504 | /* |
1505 | * re-enable interrupts if there are users left, or the |
1506 | * user wishes vblank interrupts to be enabled all the time. |
1507 | */ |
1508 | if (atomic_read(v: &vblank->refcount) != 0 || drm_vblank_offdelay == 0) |
1509 | drm_WARN_ON(dev, drm_vblank_enable(dev, pipe)); |
1510 | spin_unlock_irq(lock: &dev->vbl_lock); |
1511 | } |
1512 | EXPORT_SYMBOL(drm_crtc_vblank_on); |
1513 | |
1514 | static void drm_vblank_restore(struct drm_device *dev, unsigned int pipe) |
1515 | { |
1516 | ktime_t t_vblank; |
1517 | struct drm_vblank_crtc *vblank; |
1518 | int framedur_ns; |
1519 | u64 diff_ns; |
1520 | u32 cur_vblank, diff = 1; |
1521 | int count = DRM_TIMESTAMP_MAXRETRIES; |
1522 | u32 max_vblank_count = drm_max_vblank_count(dev, pipe); |
1523 | |
1524 | if (drm_WARN_ON(dev, pipe >= dev->num_crtcs)) |
1525 | return; |
1526 | |
1527 | assert_spin_locked(&dev->vbl_lock); |
1528 | assert_spin_locked(&dev->vblank_time_lock); |
1529 | |
1530 | vblank = &dev->vblank[pipe]; |
1531 | drm_WARN_ONCE(dev, |
1532 | drm_debug_enabled(DRM_UT_VBL) && !vblank->framedur_ns, |
1533 | "Cannot compute missed vblanks without frame duration\n" ); |
1534 | framedur_ns = vblank->framedur_ns; |
1535 | |
1536 | do { |
1537 | cur_vblank = __get_vblank_counter(dev, pipe); |
1538 | drm_get_last_vbltimestamp(dev, pipe, tvblank: &t_vblank, in_vblank_irq: false); |
1539 | } while (cur_vblank != __get_vblank_counter(dev, pipe) && --count > 0); |
1540 | |
1541 | diff_ns = ktime_to_ns(ktime_sub(t_vblank, vblank->time)); |
1542 | if (framedur_ns) |
1543 | diff = DIV_ROUND_CLOSEST_ULL(diff_ns, framedur_ns); |
1544 | |
1545 | |
1546 | drm_dbg_vbl(dev, |
1547 | "missed %d vblanks in %lld ns, frame duration=%d ns, hw_diff=%d\n" , |
1548 | diff, diff_ns, framedur_ns, cur_vblank - vblank->last); |
1549 | vblank->last = (cur_vblank - diff) & max_vblank_count; |
1550 | } |
1551 | |
1552 | /** |
1553 | * drm_crtc_vblank_restore - estimate missed vblanks and update vblank count. |
1554 | * @crtc: CRTC in question |
1555 | * |
1556 | * Power manamement features can cause frame counter resets between vblank |
1557 | * disable and enable. Drivers can use this function in their |
1558 | * &drm_crtc_funcs.enable_vblank implementation to estimate missed vblanks since |
1559 | * the last &drm_crtc_funcs.disable_vblank using timestamps and update the |
1560 | * vblank counter. |
1561 | * |
1562 | * Note that drivers must have race-free high-precision timestamping support, |
1563 | * i.e. &drm_crtc_funcs.get_vblank_timestamp must be hooked up and |
1564 | * &drm_driver.vblank_disable_immediate must be set to indicate the |
1565 | * time-stamping functions are race-free against vblank hardware counter |
1566 | * increments. |
1567 | */ |
1568 | void drm_crtc_vblank_restore(struct drm_crtc *crtc) |
1569 | { |
1570 | WARN_ON_ONCE(!crtc->funcs->get_vblank_timestamp); |
1571 | WARN_ON_ONCE(!crtc->dev->vblank_disable_immediate); |
1572 | |
1573 | drm_vblank_restore(dev: crtc->dev, pipe: drm_crtc_index(crtc)); |
1574 | } |
1575 | EXPORT_SYMBOL(drm_crtc_vblank_restore); |
1576 | |
1577 | static void drm_legacy_vblank_pre_modeset(struct drm_device *dev, |
1578 | unsigned int pipe) |
1579 | { |
1580 | struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; |
1581 | |
1582 | /* vblank is not initialized (IRQ not installed ?), or has been freed */ |
1583 | if (!drm_dev_has_vblank(dev)) |
1584 | return; |
1585 | |
1586 | if (drm_WARN_ON(dev, pipe >= dev->num_crtcs)) |
1587 | return; |
1588 | |
1589 | /* |
1590 | * To avoid all the problems that might happen if interrupts |
1591 | * were enabled/disabled around or between these calls, we just |
1592 | * have the kernel take a reference on the CRTC (just once though |
1593 | * to avoid corrupting the count if multiple, mismatch calls occur), |
1594 | * so that interrupts remain enabled in the interim. |
1595 | */ |
1596 | if (!vblank->inmodeset) { |
1597 | vblank->inmodeset = 0x1; |
1598 | if (drm_vblank_get(dev, pipe) == 0) |
1599 | vblank->inmodeset |= 0x2; |
1600 | } |
1601 | } |
1602 | |
1603 | static void drm_legacy_vblank_post_modeset(struct drm_device *dev, |
1604 | unsigned int pipe) |
1605 | { |
1606 | struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; |
1607 | |
1608 | /* vblank is not initialized (IRQ not installed ?), or has been freed */ |
1609 | if (!drm_dev_has_vblank(dev)) |
1610 | return; |
1611 | |
1612 | if (drm_WARN_ON(dev, pipe >= dev->num_crtcs)) |
1613 | return; |
1614 | |
1615 | if (vblank->inmodeset) { |
1616 | spin_lock_irq(lock: &dev->vbl_lock); |
1617 | drm_reset_vblank_timestamp(dev, pipe); |
1618 | spin_unlock_irq(lock: &dev->vbl_lock); |
1619 | |
1620 | if (vblank->inmodeset & 0x2) |
1621 | drm_vblank_put(dev, pipe); |
1622 | |
1623 | vblank->inmodeset = 0; |
1624 | } |
1625 | } |
1626 | |
1627 | int drm_legacy_modeset_ctl_ioctl(struct drm_device *dev, void *data, |
1628 | struct drm_file *file_priv) |
1629 | { |
1630 | struct drm_modeset_ctl *modeset = data; |
1631 | unsigned int pipe; |
1632 | |
1633 | /* If drm_vblank_init() hasn't been called yet, just no-op */ |
1634 | if (!drm_dev_has_vblank(dev)) |
1635 | return 0; |
1636 | |
1637 | /* KMS drivers handle this internally */ |
1638 | if (!drm_core_check_feature(dev, feature: DRIVER_LEGACY)) |
1639 | return 0; |
1640 | |
1641 | pipe = modeset->crtc; |
1642 | if (pipe >= dev->num_crtcs) |
1643 | return -EINVAL; |
1644 | |
1645 | switch (modeset->cmd) { |
1646 | case _DRM_PRE_MODESET: |
1647 | drm_legacy_vblank_pre_modeset(dev, pipe); |
1648 | break; |
1649 | case _DRM_POST_MODESET: |
1650 | drm_legacy_vblank_post_modeset(dev, pipe); |
1651 | break; |
1652 | default: |
1653 | return -EINVAL; |
1654 | } |
1655 | |
1656 | return 0; |
1657 | } |
1658 | |
1659 | static int drm_queue_vblank_event(struct drm_device *dev, unsigned int pipe, |
1660 | u64 req_seq, |
1661 | union drm_wait_vblank *vblwait, |
1662 | struct drm_file *file_priv) |
1663 | { |
1664 | struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; |
1665 | struct drm_pending_vblank_event *e; |
1666 | ktime_t now; |
1667 | u64 seq; |
1668 | int ret; |
1669 | |
1670 | e = kzalloc(size: sizeof(*e), GFP_KERNEL); |
1671 | if (e == NULL) { |
1672 | ret = -ENOMEM; |
1673 | goto err_put; |
1674 | } |
1675 | |
1676 | e->pipe = pipe; |
1677 | e->event.base.type = DRM_EVENT_VBLANK; |
1678 | e->event.base.length = sizeof(e->event.vbl); |
1679 | e->event.vbl.user_data = vblwait->request.signal; |
1680 | e->event.vbl.crtc_id = 0; |
1681 | if (drm_core_check_feature(dev, feature: DRIVER_MODESET)) { |
1682 | struct drm_crtc *crtc = drm_crtc_from_index(dev, idx: pipe); |
1683 | |
1684 | if (crtc) |
1685 | e->event.vbl.crtc_id = crtc->base.id; |
1686 | } |
1687 | |
1688 | spin_lock_irq(lock: &dev->event_lock); |
1689 | |
1690 | /* |
1691 | * drm_crtc_vblank_off() might have been called after we called |
1692 | * drm_vblank_get(). drm_crtc_vblank_off() holds event_lock around the |
1693 | * vblank disable, so no need for further locking. The reference from |
1694 | * drm_vblank_get() protects against vblank disable from another source. |
1695 | */ |
1696 | if (!READ_ONCE(vblank->enabled)) { |
1697 | ret = -EINVAL; |
1698 | goto err_unlock; |
1699 | } |
1700 | |
1701 | ret = drm_event_reserve_init_locked(dev, file_priv, p: &e->base, |
1702 | e: &e->event.base); |
1703 | |
1704 | if (ret) |
1705 | goto err_unlock; |
1706 | |
1707 | seq = drm_vblank_count_and_time(dev, pipe, vblanktime: &now); |
1708 | |
1709 | drm_dbg_core(dev, "event on vblank count %llu, current %llu, crtc %u\n" , |
1710 | req_seq, seq, pipe); |
1711 | |
1712 | trace_drm_vblank_event_queued(file: file_priv, crtc: pipe, seq: req_seq); |
1713 | |
1714 | e->sequence = req_seq; |
1715 | if (drm_vblank_passed(seq, ref: req_seq)) { |
1716 | drm_vblank_put(dev, pipe); |
1717 | send_vblank_event(dev, e, seq, now); |
1718 | vblwait->reply.sequence = seq; |
1719 | } else { |
1720 | /* drm_handle_vblank_events will call drm_vblank_put */ |
1721 | list_add_tail(new: &e->base.link, head: &dev->vblank_event_list); |
1722 | vblwait->reply.sequence = req_seq; |
1723 | } |
1724 | |
1725 | spin_unlock_irq(lock: &dev->event_lock); |
1726 | |
1727 | return 0; |
1728 | |
1729 | err_unlock: |
1730 | spin_unlock_irq(lock: &dev->event_lock); |
1731 | kfree(objp: e); |
1732 | err_put: |
1733 | drm_vblank_put(dev, pipe); |
1734 | return ret; |
1735 | } |
1736 | |
1737 | static bool drm_wait_vblank_is_query(union drm_wait_vblank *vblwait) |
1738 | { |
1739 | if (vblwait->request.sequence) |
1740 | return false; |
1741 | |
1742 | return _DRM_VBLANK_RELATIVE == |
1743 | (vblwait->request.type & (_DRM_VBLANK_TYPES_MASK | |
1744 | _DRM_VBLANK_EVENT | |
1745 | _DRM_VBLANK_NEXTONMISS)); |
1746 | } |
1747 | |
1748 | /* |
1749 | * Widen a 32-bit param to 64-bits. |
1750 | * |
1751 | * \param narrow 32-bit value (missing upper 32 bits) |
1752 | * \param near 64-bit value that should be 'close' to near |
1753 | * |
1754 | * This function returns a 64-bit value using the lower 32-bits from |
1755 | * 'narrow' and constructing the upper 32-bits so that the result is |
1756 | * as close as possible to 'near'. |
1757 | */ |
1758 | |
1759 | static u64 widen_32_to_64(u32 narrow, u64 near) |
1760 | { |
1761 | return near + (s32) (narrow - near); |
1762 | } |
1763 | |
1764 | static void drm_wait_vblank_reply(struct drm_device *dev, unsigned int pipe, |
1765 | struct drm_wait_vblank_reply *reply) |
1766 | { |
1767 | ktime_t now; |
1768 | struct timespec64 ts; |
1769 | |
1770 | /* |
1771 | * drm_wait_vblank_reply is a UAPI structure that uses 'long' |
1772 | * to store the seconds. This is safe as we always use monotonic |
1773 | * timestamps since linux-4.15. |
1774 | */ |
1775 | reply->sequence = drm_vblank_count_and_time(dev, pipe, vblanktime: &now); |
1776 | ts = ktime_to_timespec64(now); |
1777 | reply->tval_sec = (u32)ts.tv_sec; |
1778 | reply->tval_usec = ts.tv_nsec / 1000; |
1779 | } |
1780 | |
1781 | static bool drm_wait_vblank_supported(struct drm_device *dev) |
1782 | { |
1783 | #if IS_ENABLED(CONFIG_DRM_LEGACY) |
1784 | if (unlikely(drm_core_check_feature(dev, DRIVER_LEGACY))) |
1785 | return dev->irq_enabled; |
1786 | #endif |
1787 | return drm_dev_has_vblank(dev); |
1788 | } |
1789 | |
1790 | int drm_wait_vblank_ioctl(struct drm_device *dev, void *data, |
1791 | struct drm_file *file_priv) |
1792 | { |
1793 | struct drm_crtc *crtc; |
1794 | struct drm_vblank_crtc *vblank; |
1795 | union drm_wait_vblank *vblwait = data; |
1796 | int ret; |
1797 | u64 req_seq, seq; |
1798 | unsigned int pipe_index; |
1799 | unsigned int flags, pipe, high_pipe; |
1800 | |
1801 | if (!drm_wait_vblank_supported(dev)) |
1802 | return -EOPNOTSUPP; |
1803 | |
1804 | if (vblwait->request.type & _DRM_VBLANK_SIGNAL) |
1805 | return -EINVAL; |
1806 | |
1807 | if (vblwait->request.type & |
1808 | ~(_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK | |
1809 | _DRM_VBLANK_HIGH_CRTC_MASK)) { |
1810 | drm_dbg_core(dev, |
1811 | "Unsupported type value 0x%x, supported mask 0x%x\n" , |
1812 | vblwait->request.type, |
1813 | (_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK | |
1814 | _DRM_VBLANK_HIGH_CRTC_MASK)); |
1815 | return -EINVAL; |
1816 | } |
1817 | |
1818 | flags = vblwait->request.type & _DRM_VBLANK_FLAGS_MASK; |
1819 | high_pipe = (vblwait->request.type & _DRM_VBLANK_HIGH_CRTC_MASK); |
1820 | if (high_pipe) |
1821 | pipe_index = high_pipe >> _DRM_VBLANK_HIGH_CRTC_SHIFT; |
1822 | else |
1823 | pipe_index = flags & _DRM_VBLANK_SECONDARY ? 1 : 0; |
1824 | |
1825 | /* Convert lease-relative crtc index into global crtc index */ |
1826 | if (drm_core_check_feature(dev, feature: DRIVER_MODESET)) { |
1827 | pipe = 0; |
1828 | drm_for_each_crtc(crtc, dev) { |
1829 | if (drm_lease_held(file_priv, id: crtc->base.id)) { |
1830 | if (pipe_index == 0) |
1831 | break; |
1832 | pipe_index--; |
1833 | } |
1834 | pipe++; |
1835 | } |
1836 | } else { |
1837 | pipe = pipe_index; |
1838 | } |
1839 | |
1840 | if (pipe >= dev->num_crtcs) |
1841 | return -EINVAL; |
1842 | |
1843 | vblank = &dev->vblank[pipe]; |
1844 | |
1845 | /* If the counter is currently enabled and accurate, short-circuit |
1846 | * queries to return the cached timestamp of the last vblank. |
1847 | */ |
1848 | if (dev->vblank_disable_immediate && |
1849 | drm_wait_vblank_is_query(vblwait) && |
1850 | READ_ONCE(vblank->enabled)) { |
1851 | drm_wait_vblank_reply(dev, pipe, reply: &vblwait->reply); |
1852 | return 0; |
1853 | } |
1854 | |
1855 | ret = drm_vblank_get(dev, pipe); |
1856 | if (ret) { |
1857 | drm_dbg_core(dev, |
1858 | "crtc %d failed to acquire vblank counter, %d\n" , |
1859 | pipe, ret); |
1860 | return ret; |
1861 | } |
1862 | seq = drm_vblank_count(dev, pipe); |
1863 | |
1864 | switch (vblwait->request.type & _DRM_VBLANK_TYPES_MASK) { |
1865 | case _DRM_VBLANK_RELATIVE: |
1866 | req_seq = seq + vblwait->request.sequence; |
1867 | vblwait->request.sequence = req_seq; |
1868 | vblwait->request.type &= ~_DRM_VBLANK_RELATIVE; |
1869 | break; |
1870 | case _DRM_VBLANK_ABSOLUTE: |
1871 | req_seq = widen_32_to_64(narrow: vblwait->request.sequence, near: seq); |
1872 | break; |
1873 | default: |
1874 | ret = -EINVAL; |
1875 | goto done; |
1876 | } |
1877 | |
1878 | if ((flags & _DRM_VBLANK_NEXTONMISS) && |
1879 | drm_vblank_passed(seq, ref: req_seq)) { |
1880 | req_seq = seq + 1; |
1881 | vblwait->request.type &= ~_DRM_VBLANK_NEXTONMISS; |
1882 | vblwait->request.sequence = req_seq; |
1883 | } |
1884 | |
1885 | if (flags & _DRM_VBLANK_EVENT) { |
1886 | /* must hold on to the vblank ref until the event fires |
1887 | * drm_vblank_put will be called asynchronously |
1888 | */ |
1889 | return drm_queue_vblank_event(dev, pipe, req_seq, vblwait, file_priv); |
1890 | } |
1891 | |
1892 | if (req_seq != seq) { |
1893 | int wait; |
1894 | |
1895 | drm_dbg_core(dev, "waiting on vblank count %llu, crtc %u\n" , |
1896 | req_seq, pipe); |
1897 | wait = wait_event_interruptible_timeout(vblank->queue, |
1898 | drm_vblank_passed(drm_vblank_count(dev, pipe), req_seq) || |
1899 | !READ_ONCE(vblank->enabled), |
1900 | msecs_to_jiffies(3000)); |
1901 | |
1902 | switch (wait) { |
1903 | case 0: |
1904 | /* timeout */ |
1905 | ret = -EBUSY; |
1906 | break; |
1907 | case -ERESTARTSYS: |
1908 | /* interrupted by signal */ |
1909 | ret = -EINTR; |
1910 | break; |
1911 | default: |
1912 | ret = 0; |
1913 | break; |
1914 | } |
1915 | } |
1916 | |
1917 | if (ret != -EINTR) { |
1918 | drm_wait_vblank_reply(dev, pipe, reply: &vblwait->reply); |
1919 | |
1920 | drm_dbg_core(dev, "crtc %d returning %u to client\n" , |
1921 | pipe, vblwait->reply.sequence); |
1922 | } else { |
1923 | drm_dbg_core(dev, "crtc %d vblank wait interrupted by signal\n" , |
1924 | pipe); |
1925 | } |
1926 | |
1927 | done: |
1928 | drm_vblank_put(dev, pipe); |
1929 | return ret; |
1930 | } |
1931 | |
1932 | static void drm_handle_vblank_events(struct drm_device *dev, unsigned int pipe) |
1933 | { |
1934 | struct drm_crtc *crtc = drm_crtc_from_index(dev, idx: pipe); |
1935 | bool high_prec = false; |
1936 | struct drm_pending_vblank_event *e, *t; |
1937 | ktime_t now; |
1938 | u64 seq; |
1939 | |
1940 | assert_spin_locked(&dev->event_lock); |
1941 | |
1942 | seq = drm_vblank_count_and_time(dev, pipe, vblanktime: &now); |
1943 | |
1944 | list_for_each_entry_safe(e, t, &dev->vblank_event_list, base.link) { |
1945 | if (e->pipe != pipe) |
1946 | continue; |
1947 | if (!drm_vblank_passed(seq, ref: e->sequence)) |
1948 | continue; |
1949 | |
1950 | drm_dbg_core(dev, "vblank event on %llu, current %llu\n" , |
1951 | e->sequence, seq); |
1952 | |
1953 | list_del(entry: &e->base.link); |
1954 | drm_vblank_put(dev, pipe); |
1955 | send_vblank_event(dev, e, seq, now); |
1956 | } |
1957 | |
1958 | if (crtc && crtc->funcs->get_vblank_timestamp) |
1959 | high_prec = true; |
1960 | |
1961 | trace_drm_vblank_event(crtc: pipe, seq, time: now, high_prec); |
1962 | } |
1963 | |
1964 | /** |
1965 | * drm_handle_vblank - handle a vblank event |
1966 | * @dev: DRM device |
1967 | * @pipe: index of CRTC where this event occurred |
1968 | * |
1969 | * Drivers should call this routine in their vblank interrupt handlers to |
1970 | * update the vblank counter and send any signals that may be pending. |
1971 | * |
1972 | * This is the legacy version of drm_crtc_handle_vblank(). |
1973 | */ |
1974 | bool drm_handle_vblank(struct drm_device *dev, unsigned int pipe) |
1975 | { |
1976 | struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; |
1977 | unsigned long irqflags; |
1978 | bool disable_irq; |
1979 | |
1980 | if (drm_WARN_ON_ONCE(dev, !drm_dev_has_vblank(dev))) |
1981 | return false; |
1982 | |
1983 | if (drm_WARN_ON(dev, pipe >= dev->num_crtcs)) |
1984 | return false; |
1985 | |
1986 | spin_lock_irqsave(&dev->event_lock, irqflags); |
1987 | |
1988 | /* Need timestamp lock to prevent concurrent execution with |
1989 | * vblank enable/disable, as this would cause inconsistent |
1990 | * or corrupted timestamps and vblank counts. |
1991 | */ |
1992 | spin_lock(lock: &dev->vblank_time_lock); |
1993 | |
1994 | /* Vblank irq handling disabled. Nothing to do. */ |
1995 | if (!vblank->enabled) { |
1996 | spin_unlock(lock: &dev->vblank_time_lock); |
1997 | spin_unlock_irqrestore(lock: &dev->event_lock, flags: irqflags); |
1998 | return false; |
1999 | } |
2000 | |
2001 | drm_update_vblank_count(dev, pipe, in_vblank_irq: true); |
2002 | |
2003 | spin_unlock(lock: &dev->vblank_time_lock); |
2004 | |
2005 | wake_up(&vblank->queue); |
2006 | |
2007 | /* With instant-off, we defer disabling the interrupt until after |
2008 | * we finish processing the following vblank after all events have |
2009 | * been signaled. The disable has to be last (after |
2010 | * drm_handle_vblank_events) so that the timestamp is always accurate. |
2011 | */ |
2012 | disable_irq = (dev->vblank_disable_immediate && |
2013 | drm_vblank_offdelay > 0 && |
2014 | !atomic_read(v: &vblank->refcount)); |
2015 | |
2016 | drm_handle_vblank_events(dev, pipe); |
2017 | drm_handle_vblank_works(vblank); |
2018 | |
2019 | spin_unlock_irqrestore(lock: &dev->event_lock, flags: irqflags); |
2020 | |
2021 | if (disable_irq) |
2022 | vblank_disable_fn(t: &vblank->disable_timer); |
2023 | |
2024 | return true; |
2025 | } |
2026 | EXPORT_SYMBOL(drm_handle_vblank); |
2027 | |
2028 | /** |
2029 | * drm_crtc_handle_vblank - handle a vblank event |
2030 | * @crtc: where this event occurred |
2031 | * |
2032 | * Drivers should call this routine in their vblank interrupt handlers to |
2033 | * update the vblank counter and send any signals that may be pending. |
2034 | * |
2035 | * This is the native KMS version of drm_handle_vblank(). |
2036 | * |
2037 | * Note that for a given vblank counter value drm_crtc_handle_vblank() |
2038 | * and drm_crtc_vblank_count() or drm_crtc_vblank_count_and_time() |
2039 | * provide a barrier: Any writes done before calling |
2040 | * drm_crtc_handle_vblank() will be visible to callers of the later |
2041 | * functions, if the vblank count is the same or a later one. |
2042 | * |
2043 | * See also &drm_vblank_crtc.count. |
2044 | * |
2045 | * Returns: |
2046 | * True if the event was successfully handled, false on failure. |
2047 | */ |
2048 | bool drm_crtc_handle_vblank(struct drm_crtc *crtc) |
2049 | { |
2050 | return drm_handle_vblank(crtc->dev, drm_crtc_index(crtc)); |
2051 | } |
2052 | EXPORT_SYMBOL(drm_crtc_handle_vblank); |
2053 | |
2054 | /* |
2055 | * Get crtc VBLANK count. |
2056 | * |
2057 | * \param dev DRM device |
2058 | * \param data user argument, pointing to a drm_crtc_get_sequence structure. |
2059 | * \param file_priv drm file private for the user's open file descriptor |
2060 | */ |
2061 | |
2062 | int drm_crtc_get_sequence_ioctl(struct drm_device *dev, void *data, |
2063 | struct drm_file *file_priv) |
2064 | { |
2065 | struct drm_crtc *crtc; |
2066 | struct drm_vblank_crtc *vblank; |
2067 | int pipe; |
2068 | struct drm_crtc_get_sequence *get_seq = data; |
2069 | ktime_t now; |
2070 | bool vblank_enabled; |
2071 | int ret; |
2072 | |
2073 | if (!drm_core_check_feature(dev, feature: DRIVER_MODESET)) |
2074 | return -EOPNOTSUPP; |
2075 | |
2076 | if (!drm_dev_has_vblank(dev)) |
2077 | return -EOPNOTSUPP; |
2078 | |
2079 | crtc = drm_crtc_find(dev, file_priv, id: get_seq->crtc_id); |
2080 | if (!crtc) |
2081 | return -ENOENT; |
2082 | |
2083 | pipe = drm_crtc_index(crtc); |
2084 | |
2085 | vblank = &dev->vblank[pipe]; |
2086 | vblank_enabled = dev->vblank_disable_immediate && READ_ONCE(vblank->enabled); |
2087 | |
2088 | if (!vblank_enabled) { |
2089 | ret = drm_crtc_vblank_get(crtc); |
2090 | if (ret) { |
2091 | drm_dbg_core(dev, |
2092 | "crtc %d failed to acquire vblank counter, %d\n" , |
2093 | pipe, ret); |
2094 | return ret; |
2095 | } |
2096 | } |
2097 | drm_modeset_lock(lock: &crtc->mutex, NULL); |
2098 | if (crtc->state) |
2099 | get_seq->active = crtc->state->enable; |
2100 | else |
2101 | get_seq->active = crtc->enabled; |
2102 | drm_modeset_unlock(lock: &crtc->mutex); |
2103 | get_seq->sequence = drm_vblank_count_and_time(dev, pipe, vblanktime: &now); |
2104 | get_seq->sequence_ns = ktime_to_ns(kt: now); |
2105 | if (!vblank_enabled) |
2106 | drm_crtc_vblank_put(crtc); |
2107 | return 0; |
2108 | } |
2109 | |
2110 | /* |
2111 | * Queue a event for VBLANK sequence |
2112 | * |
2113 | * \param dev DRM device |
2114 | * \param data user argument, pointing to a drm_crtc_queue_sequence structure. |
2115 | * \param file_priv drm file private for the user's open file descriptor |
2116 | */ |
2117 | |
2118 | int drm_crtc_queue_sequence_ioctl(struct drm_device *dev, void *data, |
2119 | struct drm_file *file_priv) |
2120 | { |
2121 | struct drm_crtc *crtc; |
2122 | struct drm_vblank_crtc *vblank; |
2123 | int pipe; |
2124 | struct drm_crtc_queue_sequence *queue_seq = data; |
2125 | ktime_t now; |
2126 | struct drm_pending_vblank_event *e; |
2127 | u32 flags; |
2128 | u64 seq; |
2129 | u64 req_seq; |
2130 | int ret; |
2131 | |
2132 | if (!drm_core_check_feature(dev, feature: DRIVER_MODESET)) |
2133 | return -EOPNOTSUPP; |
2134 | |
2135 | if (!drm_dev_has_vblank(dev)) |
2136 | return -EOPNOTSUPP; |
2137 | |
2138 | crtc = drm_crtc_find(dev, file_priv, id: queue_seq->crtc_id); |
2139 | if (!crtc) |
2140 | return -ENOENT; |
2141 | |
2142 | flags = queue_seq->flags; |
2143 | /* Check valid flag bits */ |
2144 | if (flags & ~(DRM_CRTC_SEQUENCE_RELATIVE| |
2145 | DRM_CRTC_SEQUENCE_NEXT_ON_MISS)) |
2146 | return -EINVAL; |
2147 | |
2148 | pipe = drm_crtc_index(crtc); |
2149 | |
2150 | vblank = &dev->vblank[pipe]; |
2151 | |
2152 | e = kzalloc(size: sizeof(*e), GFP_KERNEL); |
2153 | if (e == NULL) |
2154 | return -ENOMEM; |
2155 | |
2156 | ret = drm_crtc_vblank_get(crtc); |
2157 | if (ret) { |
2158 | drm_dbg_core(dev, |
2159 | "crtc %d failed to acquire vblank counter, %d\n" , |
2160 | pipe, ret); |
2161 | goto err_free; |
2162 | } |
2163 | |
2164 | seq = drm_vblank_count_and_time(dev, pipe, vblanktime: &now); |
2165 | req_seq = queue_seq->sequence; |
2166 | |
2167 | if (flags & DRM_CRTC_SEQUENCE_RELATIVE) |
2168 | req_seq += seq; |
2169 | |
2170 | if ((flags & DRM_CRTC_SEQUENCE_NEXT_ON_MISS) && drm_vblank_passed(seq, ref: req_seq)) |
2171 | req_seq = seq + 1; |
2172 | |
2173 | e->pipe = pipe; |
2174 | e->event.base.type = DRM_EVENT_CRTC_SEQUENCE; |
2175 | e->event.base.length = sizeof(e->event.seq); |
2176 | e->event.seq.user_data = queue_seq->user_data; |
2177 | |
2178 | spin_lock_irq(lock: &dev->event_lock); |
2179 | |
2180 | /* |
2181 | * drm_crtc_vblank_off() might have been called after we called |
2182 | * drm_crtc_vblank_get(). drm_crtc_vblank_off() holds event_lock around the |
2183 | * vblank disable, so no need for further locking. The reference from |
2184 | * drm_crtc_vblank_get() protects against vblank disable from another source. |
2185 | */ |
2186 | if (!READ_ONCE(vblank->enabled)) { |
2187 | ret = -EINVAL; |
2188 | goto err_unlock; |
2189 | } |
2190 | |
2191 | ret = drm_event_reserve_init_locked(dev, file_priv, p: &e->base, |
2192 | e: &e->event.base); |
2193 | |
2194 | if (ret) |
2195 | goto err_unlock; |
2196 | |
2197 | e->sequence = req_seq; |
2198 | |
2199 | if (drm_vblank_passed(seq, ref: req_seq)) { |
2200 | drm_crtc_vblank_put(crtc); |
2201 | send_vblank_event(dev, e, seq, now); |
2202 | queue_seq->sequence = seq; |
2203 | } else { |
2204 | /* drm_handle_vblank_events will call drm_vblank_put */ |
2205 | list_add_tail(new: &e->base.link, head: &dev->vblank_event_list); |
2206 | queue_seq->sequence = req_seq; |
2207 | } |
2208 | |
2209 | spin_unlock_irq(lock: &dev->event_lock); |
2210 | return 0; |
2211 | |
2212 | err_unlock: |
2213 | spin_unlock_irq(lock: &dev->event_lock); |
2214 | drm_crtc_vblank_put(crtc); |
2215 | err_free: |
2216 | kfree(objp: e); |
2217 | return ret; |
2218 | } |
2219 | |
2220 | |