FreeBSD/Linux Kernel Cross Reference
sys/dev/drm2/drm_irq.c
1 /**
2 * \file drm_irq.c
3 * IRQ support
4 *
5 * \author Rickard E. (Rik) Faith <faith@valinux.com>
6 * \author Gareth Hughes <gareth@valinux.com>
7 */
8
9 /*
10 * Created: Fri Mar 19 14:30:16 1999 by faith@valinux.com
11 *
12 * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
13 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
14 * All Rights Reserved.
15 *
16 * Permission is hereby granted, free of charge, to any person obtaining a
17 * copy of this software and associated documentation files (the "Software"),
18 * to deal in the Software without restriction, including without limitation
19 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
20 * and/or sell copies of the Software, and to permit persons to whom the
21 * Software is furnished to do so, subject to the following conditions:
22 *
23 * The above copyright notice and this permission notice (including the next
24 * paragraph) shall be included in all copies or substantial portions of the
25 * Software.
26 *
27 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
28 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
29 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
30 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
31 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
32 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
33 * OTHER DEALINGS IN THE SOFTWARE.
34 */
35
36 #include <sys/cdefs.h>
37 __FBSDID("$FreeBSD$");
38
39 #include <dev/drm2/drmP.h>
40
41 /* Access macro for slots in vblank timestamp ringbuffer. */
42 #define vblanktimestamp(dev, crtc, count) ( \
43 (dev)->_vblank_time[(crtc) * DRM_VBLANKTIME_RBSIZE + \
44 ((count) % DRM_VBLANKTIME_RBSIZE)])
45
46 /* Retry timestamp calculation up to 3 times to satisfy
47 * drm_timestamp_precision before giving up.
48 */
49 #define DRM_TIMESTAMP_MAXRETRIES 3
50
51 /* Threshold in nanoseconds for detection of redundant
52 * vblank irq in drm_handle_vblank(). 1 msec should be ok.
53 */
54 #define DRM_REDUNDANT_VBLIRQ_THRESH_NS 1000000
55
56 /**
57 * Get interrupt from bus id.
58 *
59 * \param inode device inode.
60 * \param file_priv DRM file private.
61 * \param cmd command.
62 * \param arg user argument, pointing to a drm_irq_busid structure.
63 * \return zero on success or a negative number on failure.
64 *
65 * Finds the PCI device with the specified bus id and gets its IRQ number.
66 * This IOCTL is deprecated, and will now return EINVAL for any busid not equal
67 * to that of the device that this DRM instance attached to.
68 */
69 int drm_irq_by_busid(struct drm_device *dev, void *data,
70 struct drm_file *file_priv)
71 {
72 struct drm_irq_busid *p = data;
73
74 if (!dev->driver->bus->irq_by_busid)
75 return -EINVAL;
76
77 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
78 return -EINVAL;
79
80 return dev->driver->bus->irq_by_busid(dev, p);
81 }
82
83 /*
84 * Clear vblank timestamp buffer for a crtc.
85 */
86 static void clear_vblank_timestamps(struct drm_device *dev, int crtc)
87 {
88 memset(&dev->_vblank_time[crtc * DRM_VBLANKTIME_RBSIZE], 0,
89 DRM_VBLANKTIME_RBSIZE * sizeof(struct timeval));
90 }
91
92 /*
93 * Disable vblank irq's on crtc, make sure that last vblank count
94 * of hardware and corresponding consistent software vblank counter
95 * are preserved, even if there are any spurious vblank irq's after
96 * disable.
97 */
98 static void vblank_disable_and_save(struct drm_device *dev, int crtc)
99 {
100 u32 vblcount;
101 s64 diff_ns;
102 int vblrc;
103 struct timeval tvblank;
104 int count = DRM_TIMESTAMP_MAXRETRIES;
105
106 /* Prevent vblank irq processing while disabling vblank irqs,
107 * so no updates of timestamps or count can happen after we've
108 * disabled. Needed to prevent races in case of delayed irq's.
109 */
110 mtx_lock(&dev->vblank_time_lock);
111
112 dev->driver->disable_vblank(dev, crtc);
113 dev->vblank_enabled[crtc] = 0;
114
115 /* No further vblank irq's will be processed after
116 * this point. Get current hardware vblank count and
117 * vblank timestamp, repeat until they are consistent.
118 *
119 * FIXME: There is still a race condition here and in
120 * drm_update_vblank_count() which can cause off-by-one
121 * reinitialization of software vblank counter. If gpu
122 * vblank counter doesn't increment exactly at the leading
123 * edge of a vblank interval, then we can lose 1 count if
124 * we happen to execute between start of vblank and the
125 * delayed gpu counter increment.
126 */
127 do {
128 dev->last_vblank[crtc] = dev->driver->get_vblank_counter(dev, crtc);
129 vblrc = drm_get_last_vbltimestamp(dev, crtc, &tvblank, 0);
130 } while (dev->last_vblank[crtc] != dev->driver->get_vblank_counter(dev, crtc) && (--count) && vblrc);
131
132 if (!count)
133 vblrc = 0;
134
135 /* Compute time difference to stored timestamp of last vblank
136 * as updated by last invocation of drm_handle_vblank() in vblank irq.
137 */
138 vblcount = atomic_read(&dev->_vblank_count[crtc]);
139 diff_ns = timeval_to_ns(&tvblank) -
140 timeval_to_ns(&vblanktimestamp(dev, crtc, vblcount));
141
142 /* If there is at least 1 msec difference between the last stored
143 * timestamp and tvblank, then we are currently executing our
144 * disable inside a new vblank interval, the tvblank timestamp
145 * corresponds to this new vblank interval and the irq handler
146 * for this vblank didn't run yet and won't run due to our disable.
147 * Therefore we need to do the job of drm_handle_vblank() and
148 * increment the vblank counter by one to account for this vblank.
149 *
150 * Skip this step if there isn't any high precision timestamp
151 * available. In that case we can't account for this and just
152 * hope for the best.
153 */
154 if ((vblrc > 0) && (abs64(diff_ns) > 1000000)) {
155 atomic_inc(&dev->_vblank_count[crtc]);
156 smp_mb__after_atomic_inc();
157 }
158
159 /* Invalidate all timestamps while vblank irq's are off. */
160 clear_vblank_timestamps(dev, crtc);
161
162 mtx_unlock(&dev->vblank_time_lock);
163 }
164
165 static void vblank_disable_fn(void *arg)
166 {
167 struct drm_device *dev = (struct drm_device *)arg;
168 int i;
169
170 if (!dev->vblank_disable_allowed)
171 return;
172
173 for (i = 0; i < dev->num_crtcs; i++) {
174 mtx_lock(&dev->vbl_lock);
175 if (atomic_read(&dev->vblank_refcount[i]) == 0 &&
176 dev->vblank_enabled[i]) {
177 DRM_DEBUG("disabling vblank on crtc %d\n", i);
178 vblank_disable_and_save(dev, i);
179 }
180 mtx_unlock(&dev->vbl_lock);
181 }
182 }
183
184 void drm_vblank_cleanup(struct drm_device *dev)
185 {
186 /* Bail if the driver didn't call drm_vblank_init() */
187 if (dev->num_crtcs == 0)
188 return;
189
190 callout_stop(&dev->vblank_disable_callout);
191
192 vblank_disable_fn(dev);
193
194 free(dev->_vblank_count, DRM_MEM_VBLANK);
195 free(dev->vblank_refcount, DRM_MEM_VBLANK);
196 free(dev->vblank_enabled, DRM_MEM_VBLANK);
197 free(dev->last_vblank, DRM_MEM_VBLANK);
198 free(dev->last_vblank_wait, DRM_MEM_VBLANK);
199 free(dev->vblank_inmodeset, DRM_MEM_VBLANK);
200 free(dev->_vblank_time, DRM_MEM_VBLANK);
201
202 mtx_destroy(&dev->vbl_lock);
203 mtx_destroy(&dev->vblank_time_lock);
204
205 dev->num_crtcs = 0;
206 }
207 EXPORT_SYMBOL(drm_vblank_cleanup);
208
209 int drm_vblank_init(struct drm_device *dev, int num_crtcs)
210 {
211 int i, ret = -ENOMEM;
212
213 callout_init(&dev->vblank_disable_callout, 1);
214 mtx_init(&dev->vbl_lock, "drmvbl", NULL, MTX_DEF);
215 mtx_init(&dev->vblank_time_lock, "drmvtl", NULL, MTX_DEF);
216
217 dev->num_crtcs = num_crtcs;
218
219 dev->_vblank_count = malloc(sizeof(atomic_t) * num_crtcs,
220 DRM_MEM_VBLANK, M_NOWAIT);
221 if (!dev->_vblank_count)
222 goto err;
223
224 dev->vblank_refcount = malloc(sizeof(atomic_t) * num_crtcs,
225 DRM_MEM_VBLANK, M_NOWAIT);
226 if (!dev->vblank_refcount)
227 goto err;
228
229 dev->vblank_enabled = malloc(num_crtcs * sizeof(int),
230 DRM_MEM_VBLANK, M_NOWAIT | M_ZERO);
231 if (!dev->vblank_enabled)
232 goto err;
233
234 dev->last_vblank = malloc(num_crtcs * sizeof(u32),
235 DRM_MEM_VBLANK, M_NOWAIT | M_ZERO);
236 if (!dev->last_vblank)
237 goto err;
238
239 dev->last_vblank_wait = malloc(num_crtcs * sizeof(u32),
240 DRM_MEM_VBLANK, M_NOWAIT | M_ZERO);
241 if (!dev->last_vblank_wait)
242 goto err;
243
244 dev->vblank_inmodeset = malloc(num_crtcs * sizeof(int),
245 DRM_MEM_VBLANK, M_NOWAIT | M_ZERO);
246 if (!dev->vblank_inmodeset)
247 goto err;
248
249 dev->_vblank_time = malloc(num_crtcs * DRM_VBLANKTIME_RBSIZE *
250 sizeof(struct timeval), DRM_MEM_VBLANK, M_NOWAIT | M_ZERO);
251 if (!dev->_vblank_time)
252 goto err;
253
254 DRM_INFO("Supports vblank timestamp caching Rev 1 (10.10.2010).\n");
255
256 /* Driver specific high-precision vblank timestamping supported? */
257 if (dev->driver->get_vblank_timestamp)
258 DRM_INFO("Driver supports precise vblank timestamp query.\n");
259 else
260 DRM_INFO("No driver support for vblank timestamp query.\n");
261
262 /* Zero per-crtc vblank stuff */
263 for (i = 0; i < num_crtcs; i++) {
264 atomic_set(&dev->_vblank_count[i], 0);
265 atomic_set(&dev->vblank_refcount[i], 0);
266 }
267
268 dev->vblank_disable_allowed = 0;
269 return 0;
270
271 err:
272 drm_vblank_cleanup(dev);
273 return ret;
274 }
275 EXPORT_SYMBOL(drm_vblank_init);
276
277 /**
278 * Install IRQ handler.
279 *
280 * \param dev DRM device.
281 *
282 * Initializes the IRQ related data. Installs the handler, calling the driver
283 * \c irq_preinstall() and \c irq_postinstall() functions
284 * before and after the installation.
285 */
286 int drm_irq_install(struct drm_device *dev)
287 {
288 int ret;
289 unsigned long sh_flags = 0;
290
291 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
292 return -EINVAL;
293
294 if (drm_dev_to_irq(dev) == 0)
295 return -EINVAL;
296
297 DRM_LOCK(dev);
298
299 /* Driver must have been initialized */
300 if (!dev->dev_private) {
301 DRM_UNLOCK(dev);
302 return -EINVAL;
303 }
304
305 if (dev->irq_enabled) {
306 DRM_UNLOCK(dev);
307 return -EBUSY;
308 }
309 dev->irq_enabled = 1;
310 DRM_UNLOCK(dev);
311
312 DRM_DEBUG("irq=%d\n", drm_dev_to_irq(dev));
313
314 /* Before installing handler */
315 if (dev->driver->irq_preinstall)
316 dev->driver->irq_preinstall(dev);
317
318 /* Install handler */
319 sh_flags = INTR_TYPE_TTY | INTR_MPSAFE;
320 if (!drm_core_check_feature(dev, DRIVER_IRQ_SHARED))
321 /*
322 * FIXME Linux<->FreeBSD: This seems to make
323 * bus_setup_intr() unhappy: it was reported to return
324 * EINVAL on an i915 board (8086:2592 in a Thinkpad
325 * X41).
326 *
327 * For now, no driver we have use that.
328 */
329 sh_flags |= INTR_EXCL;
330
331 ret = -bus_setup_intr(dev->dev, dev->irqr, sh_flags, NULL,
332 dev->driver->irq_handler, dev, &dev->irqh);
333
334 if (ret < 0) {
335 device_printf(dev->dev, "Error setting interrupt: %d\n", -ret);
336 DRM_LOCK(dev);
337 dev->irq_enabled = 0;
338 DRM_UNLOCK(dev);
339 return ret;
340 }
341
342 /* After installing handler */
343 if (dev->driver->irq_postinstall)
344 ret = dev->driver->irq_postinstall(dev);
345
346 if (ret < 0) {
347 DRM_LOCK(dev);
348 dev->irq_enabled = 0;
349 DRM_UNLOCK(dev);
350 bus_teardown_intr(dev->dev, dev->irqr, dev->irqh);
351 dev->driver->bus->free_irq(dev);
352 }
353
354 return ret;
355 }
356 EXPORT_SYMBOL(drm_irq_install);
357
358 /**
359 * Uninstall the IRQ handler.
360 *
361 * \param dev DRM device.
362 *
363 * Calls the driver's \c irq_uninstall() function, and stops the irq.
364 */
365 int drm_irq_uninstall(struct drm_device *dev)
366 {
367 int irq_enabled, i;
368
369 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
370 return -EINVAL;
371
372 DRM_LOCK(dev);
373 irq_enabled = dev->irq_enabled;
374 dev->irq_enabled = 0;
375 DRM_UNLOCK(dev);
376
377 /*
378 * Wake up any waiters so they don't hang.
379 */
380 if (dev->num_crtcs) {
381 mtx_lock(&dev->vbl_lock);
382 for (i = 0; i < dev->num_crtcs; i++) {
383 DRM_WAKEUP(&dev->_vblank_count[i]);
384 dev->vblank_enabled[i] = 0;
385 dev->last_vblank[i] =
386 dev->driver->get_vblank_counter(dev, i);
387 }
388 mtx_unlock(&dev->vbl_lock);
389 }
390
391 if (!irq_enabled)
392 return -EINVAL;
393
394 DRM_DEBUG("irq=%d\n", drm_dev_to_irq(dev));
395
396 if (dev->driver->irq_uninstall)
397 dev->driver->irq_uninstall(dev);
398
399 bus_teardown_intr(dev->dev, dev->irqr, dev->irqh);
400 dev->driver->bus->free_irq(dev);
401
402 return 0;
403 }
404 EXPORT_SYMBOL(drm_irq_uninstall);
405
406 /**
407 * IRQ control ioctl.
408 *
409 * \param inode device inode.
410 * \param file_priv DRM file private.
411 * \param cmd command.
412 * \param arg user argument, pointing to a drm_control structure.
413 * \return zero on success or a negative number on failure.
414 *
415 * Calls irq_install() or irq_uninstall() according to \p arg.
416 */
417 int drm_control(struct drm_device *dev, void *data,
418 struct drm_file *file_priv)
419 {
420 struct drm_control *ctl = data;
421
422 /* if we haven't irq we fallback for compatibility reasons -
423 * this used to be a separate function in drm_dma.h
424 */
425
426
427 switch (ctl->func) {
428 case DRM_INST_HANDLER:
429 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
430 return 0;
431 if (drm_core_check_feature(dev, DRIVER_MODESET))
432 return 0;
433 if (dev->if_version < DRM_IF_VERSION(1, 2) &&
434 ctl->irq != drm_dev_to_irq(dev))
435 return -EINVAL;
436 return drm_irq_install(dev);
437 case DRM_UNINST_HANDLER:
438 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
439 return 0;
440 if (drm_core_check_feature(dev, DRIVER_MODESET))
441 return 0;
442 return drm_irq_uninstall(dev);
443 default:
444 return -EINVAL;
445 }
446 }
447
448 /**
449 * drm_calc_timestamping_constants - Calculate and
450 * store various constants which are later needed by
451 * vblank and swap-completion timestamping, e.g, by
452 * drm_calc_vbltimestamp_from_scanoutpos().
453 * They are derived from crtc's true scanout timing,
454 * so they take things like panel scaling or other
455 * adjustments into account.
456 *
457 * @crtc drm_crtc whose timestamp constants should be updated.
458 *
459 */
460 void drm_calc_timestamping_constants(struct drm_crtc *crtc)
461 {
462 s64 linedur_ns = 0, pixeldur_ns = 0, framedur_ns = 0;
463 u64 dotclock;
464
465 /* Dot clock in Hz: */
466 dotclock = (u64) crtc->hwmode.clock * 1000;
467
468 /* Fields of interlaced scanout modes are only halve a frame duration.
469 * Double the dotclock to get halve the frame-/line-/pixelduration.
470 */
471 if (crtc->hwmode.flags & DRM_MODE_FLAG_INTERLACE)
472 dotclock *= 2;
473
474 /* Valid dotclock? */
475 if (dotclock > 0) {
476 /* Convert scanline length in pixels and video dot clock to
477 * line duration, frame duration and pixel duration in
478 * nanoseconds:
479 */
480 pixeldur_ns = (s64) div64_u64(1000000000, dotclock);
481 linedur_ns = (s64) div64_u64(((u64) crtc->hwmode.crtc_htotal *
482 1000000000), dotclock);
483 framedur_ns = (s64) crtc->hwmode.crtc_vtotal * linedur_ns;
484 } else
485 DRM_ERROR("crtc %d: Can't calculate constants, dotclock = 0!\n",
486 crtc->base.id);
487
488 crtc->pixeldur_ns = pixeldur_ns;
489 crtc->linedur_ns = linedur_ns;
490 crtc->framedur_ns = framedur_ns;
491
492 DRM_DEBUG("crtc %d: hwmode: htotal %d, vtotal %d, vdisplay %d\n",
493 crtc->base.id, crtc->hwmode.crtc_htotal,
494 crtc->hwmode.crtc_vtotal, crtc->hwmode.crtc_vdisplay);
495 DRM_DEBUG("crtc %d: clock %d kHz framedur %d linedur %d, pixeldur %d\n",
496 crtc->base.id, (int) dotclock/1000, (int) framedur_ns,
497 (int) linedur_ns, (int) pixeldur_ns);
498 }
499 EXPORT_SYMBOL(drm_calc_timestamping_constants);
500
501 /**
502 * drm_calc_vbltimestamp_from_scanoutpos - helper routine for kms
503 * drivers. Implements calculation of exact vblank timestamps from
504 * given drm_display_mode timings and current video scanout position
505 * of a crtc. This can be called from within get_vblank_timestamp()
506 * implementation of a kms driver to implement the actual timestamping.
507 *
508 * Should return timestamps conforming to the OML_sync_control OpenML
509 * extension specification. The timestamp corresponds to the end of
510 * the vblank interval, aka start of scanout of topmost-leftmost display
511 * pixel in the following video frame.
512 *
513 * Requires support for optional dev->driver->get_scanout_position()
514 * in kms driver, plus a bit of setup code to provide a drm_display_mode
515 * that corresponds to the true scanout timing.
516 *
517 * The current implementation only handles standard video modes. It
518 * returns as no operation if a doublescan or interlaced video mode is
519 * active. Higher level code is expected to handle this.
520 *
521 * @dev: DRM device.
522 * @crtc: Which crtc's vblank timestamp to retrieve.
523 * @max_error: Desired maximum allowable error in timestamps (nanosecs).
524 * On return contains true maximum error of timestamp.
525 * @vblank_time: Pointer to struct timeval which should receive the timestamp.
526 * @flags: Flags to pass to driver:
527 * 0 = Default.
528 * DRM_CALLED_FROM_VBLIRQ = If function is called from vbl irq handler.
529 * @refcrtc: drm_crtc* of crtc which defines scanout timing.
530 *
531 * Returns negative value on error, failure or if not supported in current
532 * video mode:
533 *
534 * -EINVAL - Invalid crtc.
535 * -EAGAIN - Temporary unavailable, e.g., called before initial modeset.
536 * -ENOTSUPP - Function not supported in current display mode.
537 * -EIO - Failed, e.g., due to failed scanout position query.
538 *
539 * Returns or'ed positive status flags on success:
540 *
541 * DRM_VBLANKTIME_SCANOUTPOS_METHOD - Signal this method used for timestamping.
542 * DRM_VBLANKTIME_INVBL - Timestamp taken while scanout was in vblank interval.
543 *
544 */
545 int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev, int crtc,
546 int *max_error,
547 struct timeval *vblank_time,
548 unsigned flags,
549 struct drm_crtc *refcrtc)
550 {
551 struct timeval stime, raw_time;
552 struct drm_display_mode *mode;
553 int vbl_status, vtotal, vdisplay;
554 int vpos, hpos, i;
555 s64 framedur_ns, linedur_ns, pixeldur_ns, delta_ns, duration_ns;
556 bool invbl;
557
558 if (crtc < 0 || crtc >= dev->num_crtcs) {
559 DRM_ERROR("Invalid crtc %d\n", crtc);
560 return -EINVAL;
561 }
562
563 /* Scanout position query not supported? Should not happen. */
564 if (!dev->driver->get_scanout_position) {
565 DRM_ERROR("Called from driver w/o get_scanout_position()!?\n");
566 return -EIO;
567 }
568
569 mode = &refcrtc->hwmode;
570 vtotal = mode->crtc_vtotal;
571 vdisplay = mode->crtc_vdisplay;
572
573 /* Durations of frames, lines, pixels in nanoseconds. */
574 framedur_ns = refcrtc->framedur_ns;
575 linedur_ns = refcrtc->linedur_ns;
576 pixeldur_ns = refcrtc->pixeldur_ns;
577
578 /* If mode timing undefined, just return as no-op:
579 * Happens during initial modesetting of a crtc.
580 */
581 if (vtotal <= 0 || vdisplay <= 0 || framedur_ns == 0) {
582 DRM_DEBUG("crtc %d: Noop due to uninitialized mode.\n", crtc);
583 return -EAGAIN;
584 }
585
586 /* Get current scanout position with system timestamp.
587 * Repeat query up to DRM_TIMESTAMP_MAXRETRIES times
588 * if single query takes longer than max_error nanoseconds.
589 *
590 * This guarantees a tight bound on maximum error if
591 * code gets preempted or delayed for some reason.
592 */
593 for (i = 0; i < DRM_TIMESTAMP_MAXRETRIES; i++) {
594 /* Disable preemption to make it very likely to
595 * succeed in the first iteration even on PREEMPT_RT kernel.
596 */
597 critical_enter();
598
599 /* Get system timestamp before query. */
600 getmicrouptime(&stime);
601
602 /* Get vertical and horizontal scanout pos. vpos, hpos. */
603 vbl_status = dev->driver->get_scanout_position(dev, crtc, &vpos, &hpos);
604
605 /* Get system timestamp after query. */
606 getmicrouptime(&raw_time);
607 #ifdef FREEBSD_NOTYET
608 if (!drm_timestamp_monotonic)
609 mono_time_offset = ktime_get_monotonic_offset();
610 #endif /* FREEBSD_NOTYET */
611
612 critical_exit();
613
614 /* Return as no-op if scanout query unsupported or failed. */
615 if (!(vbl_status & DRM_SCANOUTPOS_VALID)) {
616 DRM_DEBUG("crtc %d : scanoutpos query failed [%d].\n",
617 crtc, vbl_status);
618 return -EIO;
619 }
620
621 duration_ns = timeval_to_ns(&raw_time) - timeval_to_ns(&stime);
622
623 /* Accept result with < max_error nsecs timing uncertainty. */
624 if (duration_ns <= (s64) *max_error)
625 break;
626 }
627
628 /* Noisy system timing? */
629 if (i == DRM_TIMESTAMP_MAXRETRIES) {
630 DRM_DEBUG("crtc %d: Noisy timestamp %d us > %d us [%d reps].\n",
631 crtc, (int) duration_ns/1000, *max_error/1000, i);
632 }
633
634 /* Return upper bound of timestamp precision error. */
635 *max_error = (int) duration_ns;
636
637 /* Check if in vblank area:
638 * vpos is >=0 in video scanout area, but negative
639 * within vblank area, counting down the number of lines until
640 * start of scanout.
641 */
642 invbl = vbl_status & DRM_SCANOUTPOS_INVBL;
643
644 /* Convert scanout position into elapsed time at raw_time query
645 * since start of scanout at first display scanline. delta_ns
646 * can be negative if start of scanout hasn't happened yet.
647 */
648 delta_ns = (s64) vpos * linedur_ns + (s64) hpos * pixeldur_ns;
649
650 /* Is vpos outside nominal vblank area, but less than
651 * 1/100 of a frame height away from start of vblank?
652 * If so, assume this isn't a massively delayed vblank
653 * interrupt, but a vblank interrupt that fired a few
654 * microseconds before true start of vblank. Compensate
655 * by adding a full frame duration to the final timestamp.
656 * Happens, e.g., on ATI R500, R600.
657 *
658 * We only do this if DRM_CALLED_FROM_VBLIRQ.
659 */
660 if ((flags & DRM_CALLED_FROM_VBLIRQ) && !invbl &&
661 ((vdisplay - vpos) < vtotal / 100)) {
662 delta_ns = delta_ns - framedur_ns;
663
664 /* Signal this correction as "applied". */
665 vbl_status |= 0x8;
666 }
667
668 #ifdef FREEBSD_NOTYET
669 if (!drm_timestamp_monotonic)
670 etime = ktime_sub(etime, mono_time_offset);
671
672 /* save this only for debugging purposes */
673 tv_etime = ktime_to_timeval(etime);
674 #endif /* FREEBSD_NOTYET */
675 /* Subtract time delta from raw timestamp to get final
676 * vblank_time timestamp for end of vblank.
677 */
678 *vblank_time = ns_to_timeval(timeval_to_ns(&raw_time) - delta_ns);
679
680 DRM_DEBUG("crtc %d : v %d p(%d,%d)@ %jd.%jd -> %jd.%jd [e %d us, %d rep]\n",
681 crtc, (int)vbl_status, hpos, vpos, (uintmax_t)raw_time.tv_sec,
682 (uintmax_t)raw_time.tv_usec, (uintmax_t)vblank_time->tv_sec,
683 (uintmax_t)vblank_time->tv_usec, (int)duration_ns/1000, i);
684
685 vbl_status = DRM_VBLANKTIME_SCANOUTPOS_METHOD;
686 if (invbl)
687 vbl_status |= DRM_VBLANKTIME_INVBL;
688
689 return vbl_status;
690 }
691 EXPORT_SYMBOL(drm_calc_vbltimestamp_from_scanoutpos);
692
693 static struct timeval get_drm_timestamp(void)
694 {
695 struct timeval now;
696
697 microtime(&now);
698 #ifdef FREEBSD_NOTYET
699 if (!drm_timestamp_monotonic)
700 now = ktime_sub(now, ktime_get_monotonic_offset());
701 #endif /* defined(FREEBSD_NOTYET) */
702
703 return now;
704 }
705
706 /**
707 * drm_get_last_vbltimestamp - retrieve raw timestamp for the most recent
708 * vblank interval.
709 *
710 * @dev: DRM device
711 * @crtc: which crtc's vblank timestamp to retrieve
712 * @tvblank: Pointer to target struct timeval which should receive the timestamp
713 * @flags: Flags to pass to driver:
714 * 0 = Default.
715 * DRM_CALLED_FROM_VBLIRQ = If function is called from vbl irq handler.
716 *
717 * Fetches the system timestamp corresponding to the time of the most recent
718 * vblank interval on specified crtc. May call into kms-driver to
719 * compute the timestamp with a high-precision GPU specific method.
720 *
721 * Returns zero if timestamp originates from uncorrected do_gettimeofday()
722 * call, i.e., it isn't very precisely locked to the true vblank.
723 *
724 * Returns non-zero if timestamp is considered to be very precise.
725 */
726 u32 drm_get_last_vbltimestamp(struct drm_device *dev, int crtc,
727 struct timeval *tvblank, unsigned flags)
728 {
729 int ret;
730
731 /* Define requested maximum error on timestamps (nanoseconds). */
732 int max_error = (int) drm_timestamp_precision * 1000;
733
734 /* Query driver if possible and precision timestamping enabled. */
735 if (dev->driver->get_vblank_timestamp && (max_error > 0)) {
736 ret = dev->driver->get_vblank_timestamp(dev, crtc, &max_error,
737 tvblank, flags);
738 if (ret > 0)
739 return (u32) ret;
740 }
741
742 /* GPU high precision timestamp query unsupported or failed.
743 * Return current monotonic/gettimeofday timestamp as best estimate.
744 */
745 *tvblank = get_drm_timestamp();
746
747 return 0;
748 }
749 EXPORT_SYMBOL(drm_get_last_vbltimestamp);
750
751 /**
752 * drm_vblank_count - retrieve "cooked" vblank counter value
753 * @dev: DRM device
754 * @crtc: which counter to retrieve
755 *
756 * Fetches the "cooked" vblank count value that represents the number of
757 * vblank events since the system was booted, including lost events due to
758 * modesetting activity.
759 */
760 u32 drm_vblank_count(struct drm_device *dev, int crtc)
761 {
762 return atomic_read(&dev->_vblank_count[crtc]);
763 }
764 EXPORT_SYMBOL(drm_vblank_count);
765
766 /**
767 * drm_vblank_count_and_time - retrieve "cooked" vblank counter value
768 * and the system timestamp corresponding to that vblank counter value.
769 *
770 * @dev: DRM device
771 * @crtc: which counter to retrieve
772 * @vblanktime: Pointer to struct timeval to receive the vblank timestamp.
773 *
774 * Fetches the "cooked" vblank count value that represents the number of
775 * vblank events since the system was booted, including lost events due to
776 * modesetting activity. Returns corresponding system timestamp of the time
777 * of the vblank interval that corresponds to the current value vblank counter
778 * value.
779 */
780 u32 drm_vblank_count_and_time(struct drm_device *dev, int crtc,
781 struct timeval *vblanktime)
782 {
783 u32 cur_vblank;
784
785 /* Read timestamp from slot of _vblank_time ringbuffer
786 * that corresponds to current vblank count. Retry if
787 * count has incremented during readout. This works like
788 * a seqlock.
789 */
790 do {
791 cur_vblank = atomic_read(&dev->_vblank_count[crtc]);
792 *vblanktime = vblanktimestamp(dev, crtc, cur_vblank);
793 smp_rmb();
794 } while (cur_vblank != atomic_read(&dev->_vblank_count[crtc]));
795
796 return cur_vblank;
797 }
798 EXPORT_SYMBOL(drm_vblank_count_and_time);
799
800 static void send_vblank_event(struct drm_device *dev,
801 struct drm_pending_vblank_event *e,
802 unsigned long seq, struct timeval *now)
803 {
804 WARN_ON_SMP(!mtx_owned(&dev->event_lock));
805 e->event.sequence = seq;
806 e->event.tv_sec = now->tv_sec;
807 e->event.tv_usec = now->tv_usec;
808
809 list_add_tail(&e->base.link,
810 &e->base.file_priv->event_list);
811 drm_event_wakeup(&e->base);
812 CTR3(KTR_DRM, "vblank_event_delivered %d %d %d",
813 e->base.pid, e->pipe, e->event.sequence);
814 }
815
816 /**
817 * drm_send_vblank_event - helper to send vblank event after pageflip
818 * @dev: DRM device
819 * @crtc: CRTC in question
820 * @e: the event to send
821 *
822 * Updates sequence # and timestamp on event, and sends it to userspace.
823 * Caller must hold event lock.
824 */
825 void drm_send_vblank_event(struct drm_device *dev, int crtc,
826 struct drm_pending_vblank_event *e)
827 {
828 struct timeval now;
829 unsigned int seq;
830 if (crtc >= 0) {
831 seq = drm_vblank_count_and_time(dev, crtc, &now);
832 } else {
833 seq = 0;
834
835 now = get_drm_timestamp();
836 }
837 send_vblank_event(dev, e, seq, &now);
838 }
839 EXPORT_SYMBOL(drm_send_vblank_event);
840
841 /**
842 * drm_update_vblank_count - update the master vblank counter
843 * @dev: DRM device
844 * @crtc: counter to update
845 *
846 * Call back into the driver to update the appropriate vblank counter
847 * (specified by @crtc). Deal with wraparound, if it occurred, and
848 * update the last read value so we can deal with wraparound on the next
849 * call if necessary.
850 *
851 * Only necessary when going from off->on, to account for frames we
852 * didn't get an interrupt for.
853 *
854 * Note: caller must hold dev->vbl_lock since this reads & writes
855 * device vblank fields.
856 */
857 static void drm_update_vblank_count(struct drm_device *dev, int crtc)
858 {
859 u32 cur_vblank, diff, tslot, rc;
860 struct timeval t_vblank;
861
862 /*
863 * Interrupts were disabled prior to this call, so deal with counter
864 * wrap if needed.
865 * NOTE! It's possible we lost a full dev->max_vblank_count events
866 * here if the register is small or we had vblank interrupts off for
867 * a long time.
868 *
869 * We repeat the hardware vblank counter & timestamp query until
870 * we get consistent results. This to prevent races between gpu
871 * updating its hardware counter while we are retrieving the
872 * corresponding vblank timestamp.
873 */
874 do {
875 cur_vblank = dev->driver->get_vblank_counter(dev, crtc);
876 rc = drm_get_last_vbltimestamp(dev, crtc, &t_vblank, 0);
877 } while (cur_vblank != dev->driver->get_vblank_counter(dev, crtc));
878
879 /* Deal with counter wrap */
880 diff = cur_vblank - dev->last_vblank[crtc];
881 if (cur_vblank < dev->last_vblank[crtc]) {
882 diff += dev->max_vblank_count;
883
884 DRM_DEBUG("last_vblank[%d]=0x%x, cur_vblank=0x%x => diff=0x%x\n",
885 crtc, dev->last_vblank[crtc], cur_vblank, diff);
886 }
887
888 DRM_DEBUG("enabling vblank interrupts on crtc %d, missed %d\n",
889 crtc, diff);
890
891 /* Reinitialize corresponding vblank timestamp if high-precision query
892 * available. Skip this step if query unsupported or failed. Will
893 * reinitialize delayed at next vblank interrupt in that case.
894 */
895 if (rc) {
896 tslot = atomic_read(&dev->_vblank_count[crtc]) + diff;
897 vblanktimestamp(dev, crtc, tslot) = t_vblank;
898 }
899
900 smp_mb__before_atomic_inc();
901 atomic_add(diff, &dev->_vblank_count[crtc]);
902 smp_mb__after_atomic_inc();
903 }
904
905 /**
906 * drm_vblank_get - get a reference count on vblank events
907 * @dev: DRM device
908 * @crtc: which CRTC to own
909 *
910 * Acquire a reference count on vblank events to avoid having them disabled
911 * while in use.
912 *
913 * RETURNS
914 * Zero on success, nonzero on failure.
915 */
916 int drm_vblank_get(struct drm_device *dev, int crtc)
917 {
918 int ret = 0;
919
920 mtx_lock(&dev->vbl_lock);
921 /* Going from 0->1 means we have to enable interrupts again */
922 if (atomic_add_return(1, &dev->vblank_refcount[crtc]) == 1) {
923 mtx_lock(&dev->vblank_time_lock);
924 if (!dev->vblank_enabled[crtc]) {
925 /* Enable vblank irqs under vblank_time_lock protection.
926 * All vblank count & timestamp updates are held off
927 * until we are done reinitializing master counter and
928 * timestamps. Filtercode in drm_handle_vblank() will
929 * prevent double-accounting of same vblank interval.
930 */
931 ret = dev->driver->enable_vblank(dev, crtc);
932 DRM_DEBUG("enabling vblank on crtc %d, ret: %d\n",
933 crtc, ret);
934 if (ret)
935 atomic_dec(&dev->vblank_refcount[crtc]);
936 else {
937 dev->vblank_enabled[crtc] = 1;
938 drm_update_vblank_count(dev, crtc);
939 }
940 }
941 mtx_unlock(&dev->vblank_time_lock);
942 } else {
943 if (!dev->vblank_enabled[crtc]) {
944 atomic_dec(&dev->vblank_refcount[crtc]);
945 ret = -EINVAL;
946 }
947 }
948 mtx_unlock(&dev->vbl_lock);
949
950 return ret;
951 }
952 EXPORT_SYMBOL(drm_vblank_get);
953
954 /**
955 * drm_vblank_put - give up ownership of vblank events
956 * @dev: DRM device
957 * @crtc: which counter to give up
958 *
959 * Release ownership of a given vblank counter, turning off interrupts
960 * if possible. Disable interrupts after drm_vblank_offdelay milliseconds.
961 */
962 void drm_vblank_put(struct drm_device *dev, int crtc)
963 {
964 BUG_ON(atomic_read(&dev->vblank_refcount[crtc]) == 0);
965
966 /* Last user schedules interrupt disable */
967 if (atomic_dec_and_test(&dev->vblank_refcount[crtc]) &&
968 (drm_vblank_offdelay > 0))
969 callout_reset(&dev->vblank_disable_callout,
970 (drm_vblank_offdelay * DRM_HZ) / 1000,
971 vblank_disable_fn, dev);
972 }
973 EXPORT_SYMBOL(drm_vblank_put);
974
975 /**
976 * drm_vblank_off - disable vblank events on a CRTC
977 * @dev: DRM device
978 * @crtc: CRTC in question
979 *
980 * Caller must hold event lock.
981 */
982 void drm_vblank_off(struct drm_device *dev, int crtc)
983 {
984 struct drm_pending_vblank_event *e, *t;
985 struct timeval now;
986 unsigned int seq;
987
988 mtx_lock(&dev->vbl_lock);
989 vblank_disable_and_save(dev, crtc);
990 DRM_WAKEUP(&dev->_vblank_count[crtc]);
991
992 /* Send any queued vblank events, lest the natives grow disquiet */
993 seq = drm_vblank_count_and_time(dev, crtc, &now);
994
995 mtx_lock(&dev->event_lock);
996 list_for_each_entry_safe(e, t, &dev->vblank_event_list, base.link) {
997 if (e->pipe != crtc)
998 continue;
999 DRM_DEBUG("Sending premature vblank event on disable: \
1000 wanted %d, current %d\n",
1001 e->event.sequence, seq);
1002 list_del(&e->base.link);
1003 drm_vblank_put(dev, e->pipe);
1004 send_vblank_event(dev, e, seq, &now);
1005 }
1006 mtx_unlock(&dev->event_lock);
1007
1008 mtx_unlock(&dev->vbl_lock);
1009 }
1010 EXPORT_SYMBOL(drm_vblank_off);
1011
1012 /**
1013 * drm_vblank_pre_modeset - account for vblanks across mode sets
1014 * @dev: DRM device
1015 * @crtc: CRTC in question
1016 *
1017 * Account for vblank events across mode setting events, which will likely
1018 * reset the hardware frame counter.
1019 */
1020 void drm_vblank_pre_modeset(struct drm_device *dev, int crtc)
1021 {
1022 /* vblank is not initialized (IRQ not installed ?), or has been freed */
1023 if (!dev->num_crtcs)
1024 return;
1025 /*
1026 * To avoid all the problems that might happen if interrupts
1027 * were enabled/disabled around or between these calls, we just
1028 * have the kernel take a reference on the CRTC (just once though
1029 * to avoid corrupting the count if multiple, mismatch calls occur),
1030 * so that interrupts remain enabled in the interim.
1031 */
1032 if (!dev->vblank_inmodeset[crtc]) {
1033 dev->vblank_inmodeset[crtc] = 0x1;
1034 if (drm_vblank_get(dev, crtc) == 0)
1035 dev->vblank_inmodeset[crtc] |= 0x2;
1036 }
1037 }
1038 EXPORT_SYMBOL(drm_vblank_pre_modeset);
1039
1040 void drm_vblank_post_modeset(struct drm_device *dev, int crtc)
1041 {
1042 /* vblank is not initialized (IRQ not installed ?), or has been freed */
1043 if (!dev->num_crtcs)
1044 return;
1045
1046 if (dev->vblank_inmodeset[crtc]) {
1047 mtx_lock(&dev->vbl_lock);
1048 dev->vblank_disable_allowed = 1;
1049 mtx_unlock(&dev->vbl_lock);
1050
1051 if (dev->vblank_inmodeset[crtc] & 0x2)
1052 drm_vblank_put(dev, crtc);
1053
1054 dev->vblank_inmodeset[crtc] = 0;
1055 }
1056 }
1057 EXPORT_SYMBOL(drm_vblank_post_modeset);
1058
1059 /**
1060 * drm_modeset_ctl - handle vblank event counter changes across mode switch
1061 * @DRM_IOCTL_ARGS: standard ioctl arguments
1062 *
1063 * Applications should call the %_DRM_PRE_MODESET and %_DRM_POST_MODESET
1064 * ioctls around modesetting so that any lost vblank events are accounted for.
1065 *
1066 * Generally the counter will reset across mode sets. If interrupts are
1067 * enabled around this call, we don't have to do anything since the counter
1068 * will have already been incremented.
1069 */
1070 int drm_modeset_ctl(struct drm_device *dev, void *data,
1071 struct drm_file *file_priv)
1072 {
1073 struct drm_modeset_ctl *modeset = data;
1074 unsigned int crtc;
1075
1076 /* If drm_vblank_init() hasn't been called yet, just no-op */
1077 if (!dev->num_crtcs)
1078 return 0;
1079
1080 /* KMS drivers handle this internally */
1081 if (drm_core_check_feature(dev, DRIVER_MODESET))
1082 return 0;
1083
1084 crtc = modeset->crtc;
1085 if (crtc >= dev->num_crtcs)
1086 return -EINVAL;
1087
1088 switch (modeset->cmd) {
1089 case _DRM_PRE_MODESET:
1090 drm_vblank_pre_modeset(dev, crtc);
1091 break;
1092 case _DRM_POST_MODESET:
1093 drm_vblank_post_modeset(dev, crtc);
1094 break;
1095 default:
1096 return -EINVAL;
1097 }
1098
1099 return 0;
1100 }
1101
1102 static void
1103 drm_vblank_event_destroy(struct drm_pending_event *e)
1104 {
1105
1106 free(e, DRM_MEM_VBLANK);
1107 }
1108
1109 static int drm_queue_vblank_event(struct drm_device *dev, int pipe,
1110 union drm_wait_vblank *vblwait,
1111 struct drm_file *file_priv)
1112 {
1113 struct drm_pending_vblank_event *e;
1114 struct timeval now;
1115 unsigned int seq;
1116 int ret;
1117
1118 e = malloc(sizeof *e, DRM_MEM_VBLANK, M_NOWAIT | M_ZERO);
1119 if (e == NULL) {
1120 ret = -ENOMEM;
1121 goto err_put;
1122 }
1123
1124 e->pipe = pipe;
1125 e->base.pid = curproc->p_pid;
1126 e->event.base.type = DRM_EVENT_VBLANK;
1127 e->event.base.length = sizeof e->event;
1128 e->event.user_data = vblwait->request.signal;
1129 e->base.event = &e->event.base;
1130 e->base.file_priv = file_priv;
1131 e->base.destroy = drm_vblank_event_destroy;
1132
1133 mtx_lock(&dev->event_lock);
1134
1135 if (file_priv->event_space < sizeof e->event) {
1136 ret = -EBUSY;
1137 goto err_unlock;
1138 }
1139
1140 file_priv->event_space -= sizeof e->event;
1141 seq = drm_vblank_count_and_time(dev, pipe, &now);
1142
1143 if ((vblwait->request.type & _DRM_VBLANK_NEXTONMISS) &&
1144 (seq - vblwait->request.sequence) <= (1 << 23)) {
1145 vblwait->request.sequence = seq + 1;
1146 vblwait->reply.sequence = vblwait->request.sequence;
1147 }
1148
1149 DRM_DEBUG("event on vblank count %d, current %d, crtc %d\n",
1150 vblwait->request.sequence, seq, pipe);
1151
1152 CTR4(KTR_DRM, "vblank_event_queued %d %d rt %x %d", curproc->p_pid, pipe,
1153 vblwait->request.type, vblwait->request.sequence);
1154
1155 e->event.sequence = vblwait->request.sequence;
1156 if ((seq - vblwait->request.sequence) <= (1 << 23)) {
1157 drm_vblank_put(dev, pipe);
1158 send_vblank_event(dev, e, seq, &now);
1159 vblwait->reply.sequence = seq;
1160 } else {
1161 /* drm_handle_vblank_events will call drm_vblank_put */
1162 list_add_tail(&e->base.link, &dev->vblank_event_list);
1163 vblwait->reply.sequence = vblwait->request.sequence;
1164 }
1165
1166 mtx_unlock(&dev->event_lock);
1167
1168 return 0;
1169
1170 err_unlock:
1171 mtx_unlock(&dev->event_lock);
1172 free(e, DRM_MEM_VBLANK);
1173 err_put:
1174 drm_vblank_put(dev, pipe);
1175 return ret;
1176 }
1177
1178 /**
1179 * Wait for VBLANK.
1180 *
1181 * \param inode device inode.
1182 * \param file_priv DRM file private.
1183 * \param cmd command.
1184 * \param data user argument, pointing to a drm_wait_vblank structure.
1185 * \return zero on success or a negative number on failure.
1186 *
1187 * This function enables the vblank interrupt on the pipe requested, then
1188 * sleeps waiting for the requested sequence number to occur, and drops
1189 * the vblank interrupt refcount afterwards. (vblank irq disable follows that
1190 * after a timeout with no further vblank waits scheduled).
1191 */
1192 int drm_wait_vblank(struct drm_device *dev, void *data,
1193 struct drm_file *file_priv)
1194 {
1195 union drm_wait_vblank *vblwait = data;
1196 int ret;
1197 unsigned int flags, seq, crtc, high_crtc;
1198
1199 if (/*(!drm_dev_to_irq(dev)) || */(!dev->irq_enabled))
1200 return -EINVAL;
1201
1202 if (vblwait->request.type & _DRM_VBLANK_SIGNAL)
1203 return -EINVAL;
1204
1205 if (vblwait->request.type &
1206 ~(_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK |
1207 _DRM_VBLANK_HIGH_CRTC_MASK)) {
1208 DRM_ERROR("Unsupported type value 0x%x, supported mask 0x%x\n",
1209 vblwait->request.type,
1210 (_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK |
1211 _DRM_VBLANK_HIGH_CRTC_MASK));
1212 return -EINVAL;
1213 }
1214
1215 flags = vblwait->request.type & _DRM_VBLANK_FLAGS_MASK;
1216 high_crtc = (vblwait->request.type & _DRM_VBLANK_HIGH_CRTC_MASK);
1217 if (high_crtc)
1218 crtc = high_crtc >> _DRM_VBLANK_HIGH_CRTC_SHIFT;
1219 else
1220 crtc = flags & _DRM_VBLANK_SECONDARY ? 1 : 0;
1221 if (crtc >= dev->num_crtcs)
1222 return -EINVAL;
1223
1224 ret = drm_vblank_get(dev, crtc);
1225 if (ret) {
1226 DRM_DEBUG("failed to acquire vblank counter, %d\n", ret);
1227 return ret;
1228 }
1229 seq = drm_vblank_count(dev, crtc);
1230
1231 switch (vblwait->request.type & _DRM_VBLANK_TYPES_MASK) {
1232 case _DRM_VBLANK_RELATIVE:
1233 vblwait->request.sequence += seq;
1234 vblwait->request.type &= ~_DRM_VBLANK_RELATIVE;
1235 case _DRM_VBLANK_ABSOLUTE:
1236 break;
1237 default:
1238 ret = -EINVAL;
1239 goto done;
1240 }
1241
1242 if (flags & _DRM_VBLANK_EVENT) {
1243 /* must hold on to the vblank ref until the event fires
1244 * drm_vblank_put will be called asynchronously
1245 */
1246 return drm_queue_vblank_event(dev, crtc, vblwait, file_priv);
1247 }
1248
1249 if ((flags & _DRM_VBLANK_NEXTONMISS) &&
1250 (seq - vblwait->request.sequence) <= (1<<23)) {
1251 vblwait->request.sequence = seq + 1;
1252 }
1253
1254 DRM_DEBUG("waiting on vblank count %d, crtc %d\n",
1255 vblwait->request.sequence, crtc);
1256 dev->last_vblank_wait[crtc] = vblwait->request.sequence;
1257 mtx_lock(&dev->vblank_time_lock);
1258 while (((drm_vblank_count(dev, crtc) - vblwait->request.sequence) >
1259 (1 << 23)) && dev->irq_enabled) {
1260 /*
1261 * The wakeups from the drm_irq_uninstall() and
1262 * drm_vblank_off() may be lost there since vbl_lock
1263 * is not held. Then, the timeout will wake us; the 3
1264 * seconds delay should not be a problem for
1265 * application when crtc is disabled or irq
1266 * uninstalled anyway.
1267 */
1268 ret = -msleep(&dev->_vblank_count[crtc], &dev->vblank_time_lock,
1269 PCATCH, "drmvbl", 3 * hz);
1270 if (ret == -ERESTART)
1271 ret = -ERESTARTSYS;
1272 if (ret != 0)
1273 break;
1274 }
1275 mtx_unlock(&dev->vblank_time_lock);
1276 if (ret != -EINTR) {
1277 struct timeval now;
1278 long reply_seq;
1279
1280 reply_seq = drm_vblank_count_and_time(dev, crtc, &now);
1281 CTR5(KTR_DRM, "wait_vblank %d %d rt %x success %d %d",
1282 curproc->p_pid, crtc, vblwait->request.type,
1283 vblwait->request.sequence, reply_seq);
1284
1285 vblwait->reply.sequence = reply_seq;
1286 vblwait->reply.tval_sec = now.tv_sec;
1287 vblwait->reply.tval_usec = now.tv_usec;
1288
1289 DRM_DEBUG("returning %d to client\n",
1290 vblwait->reply.sequence);
1291 } else {
1292 CTR5(KTR_DRM, "wait_vblank %d %d rt %x error %d %d",
1293 curproc->p_pid, crtc, vblwait->request.type, ret,
1294 vblwait->request.sequence);
1295
1296 DRM_DEBUG("vblank wait interrupted by signal\n");
1297 }
1298
1299 done:
1300 drm_vblank_put(dev, crtc);
1301 return ret;
1302 }
1303
1304 static void drm_handle_vblank_events(struct drm_device *dev, int crtc)
1305 {
1306 struct drm_pending_vblank_event *e, *t;
1307 struct timeval now;
1308 unsigned int seq;
1309
1310 seq = drm_vblank_count_and_time(dev, crtc, &now);
1311
1312 mtx_lock(&dev->event_lock);
1313
1314 list_for_each_entry_safe(e, t, &dev->vblank_event_list, base.link) {
1315 if (e->pipe != crtc)
1316 continue;
1317 if ((seq - e->event.sequence) > (1<<23))
1318 continue;
1319
1320 DRM_DEBUG("vblank event on %d, current %d\n",
1321 e->event.sequence, seq);
1322
1323 list_del(&e->base.link);
1324 drm_vblank_put(dev, e->pipe);
1325 send_vblank_event(dev, e, seq, &now);
1326 }
1327
1328 mtx_unlock(&dev->event_lock);
1329
1330 CTR2(KTR_DRM, "drm_handle_vblank_events %d %d", seq, crtc);
1331 }
1332
1333 /**
1334 * drm_handle_vblank - handle a vblank event
1335 * @dev: DRM device
1336 * @crtc: where this event occurred
1337 *
1338 * Drivers should call this routine in their vblank interrupt handlers to
1339 * update the vblank counter and send any signals that may be pending.
1340 */
1341 bool drm_handle_vblank(struct drm_device *dev, int crtc)
1342 {
1343 u32 vblcount;
1344 s64 diff_ns;
1345 struct timeval tvblank;
1346
1347 if (!dev->num_crtcs)
1348 return false;
1349
1350 /* Need timestamp lock to prevent concurrent execution with
1351 * vblank enable/disable, as this would cause inconsistent
1352 * or corrupted timestamps and vblank counts.
1353 */
1354 mtx_lock(&dev->vblank_time_lock);
1355
1356 /* Vblank irq handling disabled. Nothing to do. */
1357 if (!dev->vblank_enabled[crtc]) {
1358 mtx_unlock(&dev->vblank_time_lock);
1359 return false;
1360 }
1361
1362 /* Fetch corresponding timestamp for this vblank interval from
1363 * driver and store it in proper slot of timestamp ringbuffer.
1364 */
1365
1366 /* Get current timestamp and count. */
1367 vblcount = atomic_read(&dev->_vblank_count[crtc]);
1368 drm_get_last_vbltimestamp(dev, crtc, &tvblank, DRM_CALLED_FROM_VBLIRQ);
1369
1370 /* Compute time difference to timestamp of last vblank */
1371 diff_ns = timeval_to_ns(&tvblank) -
1372 timeval_to_ns(&vblanktimestamp(dev, crtc, vblcount));
1373
1374 /* Update vblank timestamp and count if at least
1375 * DRM_REDUNDANT_VBLIRQ_THRESH_NS nanoseconds
1376 * difference between last stored timestamp and current
1377 * timestamp. A smaller difference means basically
1378 * identical timestamps. Happens if this vblank has
1379 * been already processed and this is a redundant call,
1380 * e.g., due to spurious vblank interrupts. We need to
1381 * ignore those for accounting.
1382 */
1383 if (abs64(diff_ns) > DRM_REDUNDANT_VBLIRQ_THRESH_NS) {
1384 /* Store new timestamp in ringbuffer. */
1385 vblanktimestamp(dev, crtc, vblcount + 1) = tvblank;
1386
1387 /* Increment cooked vblank count. This also atomically commits
1388 * the timestamp computed above.
1389 */
1390 smp_mb__before_atomic_inc();
1391 atomic_inc(&dev->_vblank_count[crtc]);
1392 smp_mb__after_atomic_inc();
1393 } else {
1394 DRM_DEBUG("crtc %d: Redundant vblirq ignored. diff_ns = %d\n",
1395 crtc, (int) diff_ns);
1396 }
1397
1398 DRM_WAKEUP(&dev->_vblank_count[crtc]);
1399 drm_handle_vblank_events(dev, crtc);
1400
1401 mtx_unlock(&dev->vblank_time_lock);
1402 return true;
1403 }
1404 EXPORT_SYMBOL(drm_handle_vblank);
Cache object: 7d6889c950f659a27c38bcf158391218
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