2 * drm_irq.c IRQ and vblank support
4 * \author Rickard E. (Rik) Faith <faith@valinux.com>
5 * \author Gareth Hughes <gareth@valinux.com>
9 * Created: Fri Mar 19 14:30:16 1999 by faith@valinux.com
11 * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
12 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
13 * All Rights Reserved.
15 * Permission is hereby granted, free of charge, to any person obtaining a
16 * copy of this software and associated documentation files (the "Software"),
17 * to deal in the Software without restriction, including without limitation
18 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
19 * and/or sell copies of the Software, and to permit persons to whom the
20 * Software is furnished to do so, subject to the following conditions:
22 * The above copyright notice and this permission notice (including the next
23 * paragraph) shall be included in all copies or substantial portions of the
26 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
27 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
28 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
29 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
30 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
31 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
32 * OTHER DEALINGS IN THE SOFTWARE.
36 #include "drm_trace.h"
37 #include "drm_internal.h"
39 #include <linux/slab.h>
41 #include <linux/export.h>
43 /* Access macro for slots in vblank timestamp ringbuffer. */
44 #define vblanktimestamp(dev, pipe, count) \
45 ((dev)->vblank[pipe].time[(count) % DRM_VBLANKTIME_RBSIZE])
47 /* Retry timestamp calculation up to 3 times to satisfy
48 * drm_timestamp_precision before giving up.
50 #define DRM_TIMESTAMP_MAXRETRIES 3
52 /* Threshold in nanoseconds for detection of redundant
53 * vblank irq in drm_handle_vblank(). 1 msec should be ok.
55 #define DRM_REDUNDANT_VBLIRQ_THRESH_NS 1000000
58 drm_get_last_vbltimestamp(struct drm_device *dev, unsigned int pipe,
59 struct timeval *tvblank, unsigned flags);
61 unsigned int drm_timestamp_precision = 20; /* Default to 20 usecs. */
64 * Default to use monotonic timestamps for wait-for-vblank and page-flip
67 unsigned int drm_timestamp_monotonic = 1;
69 int drm_vblank_offdelay = 5000; /* Default to 5000 msecs. */
71 module_param_named(vblankoffdelay, drm_vblank_offdelay, int, 0600);
72 module_param_named(timestamp_precision_usec, drm_timestamp_precision, int, 0600);
73 module_param_named(timestamp_monotonic, drm_timestamp_monotonic, int, 0600);
75 static void store_vblank(struct drm_device *dev, unsigned int pipe,
77 struct timeval *t_vblank, u32 last)
79 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
82 assert_spin_locked(&dev->vblank_time_lock);
86 /* All writers hold the spinlock, but readers are serialized by
87 * the latching of vblank->count below.
89 tslot = vblank->count + vblank_count_inc;
90 vblanktimestamp(dev, pipe, tslot) = *t_vblank;
93 * vblank timestamp updates are protected on the write side with
94 * vblank_time_lock, but on the read side done locklessly using a
95 * sequence-lock on the vblank counter. Ensure correct ordering using
96 * memory barrriers. We need the barrier both before and also after the
97 * counter update to synchronize with the next timestamp write.
98 * The read-side barriers for this are in drm_vblank_count_and_time.
101 vblank->count += vblank_count_inc;
106 * drm_reset_vblank_timestamp - reset the last timestamp to the last vblank
108 * @pipe: index of CRTC for which to reset the timestamp
110 * Reset the stored timestamp for the current vblank count to correspond
111 * to the last vblank occurred.
113 * Only to be called from drm_vblank_on().
115 * Note: caller must hold dev->vbl_lock since this reads & writes
116 * device vblank fields.
118 static void drm_reset_vblank_timestamp(struct drm_device *dev, unsigned int pipe)
122 struct timeval t_vblank;
123 int count = DRM_TIMESTAMP_MAXRETRIES;
125 lockmgr(&dev->vblank_time_lock, LK_EXCLUSIVE);
128 * sample the current counter to avoid random jumps
129 * when drm_vblank_enable() applies the diff
132 cur_vblank = dev->driver->get_vblank_counter(dev, pipe);
133 rc = drm_get_last_vbltimestamp(dev, pipe, &t_vblank, 0);
134 } while (cur_vblank != dev->driver->get_vblank_counter(dev, pipe) && --count > 0);
137 * Only reinitialize corresponding vblank timestamp if high-precision query
138 * available and didn't fail. Otherwise reinitialize delayed at next vblank
139 * interrupt and assign 0 for now, to mark the vblanktimestamp as invalid.
142 t_vblank = (struct timeval) {0, 0};
145 * +1 to make sure user will never see the same
146 * vblank counter value before and after a modeset
148 store_vblank(dev, pipe, 1, &t_vblank, cur_vblank);
150 lockmgr(&dev->vblank_time_lock, LK_RELEASE);
154 * drm_update_vblank_count - update the master vblank counter
156 * @pipe: counter to update
158 * Call back into the driver to update the appropriate vblank counter
159 * (specified by @pipe). Deal with wraparound, if it occurred, and
160 * update the last read value so we can deal with wraparound on the next
163 * Only necessary when going from off->on, to account for frames we
164 * didn't get an interrupt for.
166 * Note: caller must hold dev->vbl_lock since this reads & writes
167 * device vblank fields.
169 static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe,
172 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
173 u32 cur_vblank, diff;
175 struct timeval t_vblank;
176 int count = DRM_TIMESTAMP_MAXRETRIES;
177 int framedur_ns = vblank->framedur_ns;
180 * Interrupts were disabled prior to this call, so deal with counter
182 * NOTE! It's possible we lost a full dev->max_vblank_count + 1 events
183 * here if the register is small or we had vblank interrupts off for
186 * We repeat the hardware vblank counter & timestamp query until
187 * we get consistent results. This to prevent races between gpu
188 * updating its hardware counter while we are retrieving the
189 * corresponding vblank timestamp.
192 cur_vblank = dev->driver->get_vblank_counter(dev, pipe);
193 rc = drm_get_last_vbltimestamp(dev, pipe, &t_vblank, flags);
194 } while (cur_vblank != dev->driver->get_vblank_counter(dev, pipe) && --count > 0);
196 if (dev->max_vblank_count != 0) {
197 /* trust the hw counter when it's around */
198 diff = (cur_vblank - vblank->last) & dev->max_vblank_count;
199 } else if (rc && framedur_ns) {
200 const struct timeval *t_old;
203 t_old = &vblanktimestamp(dev, pipe, vblank->count);
204 diff_ns = timeval_to_ns(&t_vblank) - timeval_to_ns(t_old);
207 * Figure out how many vblanks we've missed based
208 * on the difference in the timestamps and the
209 * frame/field duration.
211 diff = DIV_ROUND_CLOSEST_ULL(diff_ns, framedur_ns);
213 if (diff == 0 && flags & DRM_CALLED_FROM_VBLIRQ)
214 DRM_DEBUG("crtc %u: Redundant vblirq ignored."
215 " diff_ns = %lld, framedur_ns = %d)\n",
216 pipe, (long long) diff_ns, framedur_ns);
218 /* some kind of default for drivers w/o accurate vbl timestamping */
219 diff = (flags & DRM_CALLED_FROM_VBLIRQ) != 0;
222 DRM_DEBUG_VBLANK("updating vblank count on crtc %u:"
223 " current=%u, diff=%u, hw=%u hw_last=%u\n",
224 pipe, vblank->count, diff, cur_vblank, vblank->last);
227 WARN_ON_ONCE(cur_vblank != vblank->last);
232 * Only reinitialize corresponding vblank timestamp if high-precision query
233 * available and didn't fail, or we were called from the vblank interrupt.
234 * Otherwise reinitialize delayed at next vblank interrupt and assign 0
235 * for now, to mark the vblanktimestamp as invalid.
237 if (!rc && (flags & DRM_CALLED_FROM_VBLIRQ) == 0)
238 t_vblank = (struct timeval) {0, 0};
240 store_vblank(dev, pipe, diff, &t_vblank, cur_vblank);
244 * Disable vblank irq's on crtc, make sure that last vblank count
245 * of hardware and corresponding consistent software vblank counter
246 * are preserved, even if there are any spurious vblank irq's after
249 static void vblank_disable_and_save(struct drm_device *dev, unsigned int pipe)
251 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
252 unsigned long irqflags;
254 /* Prevent vblank irq processing while disabling vblank irqs,
255 * so no updates of timestamps or count can happen after we've
256 * disabled. Needed to prevent races in case of delayed irq's.
258 spin_lock_irqsave(&dev->vblank_time_lock, irqflags);
261 * Only disable vblank interrupts if they're enabled. This avoids
262 * calling the ->disable_vblank() operation in atomic context with the
263 * hardware potentially runtime suspended.
265 if (vblank->enabled) {
266 dev->driver->disable_vblank(dev, pipe);
267 vblank->enabled = false;
271 * Always update the count and timestamp to maintain the
272 * appearance that the counter has been ticking all along until
273 * this time. This makes the count account for the entire time
274 * between drm_vblank_on() and drm_vblank_off().
276 drm_update_vblank_count(dev, pipe, 0);
278 spin_unlock_irqrestore(&dev->vblank_time_lock, irqflags);
281 static void vblank_disable_fn(unsigned long arg)
283 struct drm_vblank_crtc *vblank = (void *)arg;
284 struct drm_device *dev = vblank->dev;
285 unsigned int pipe = vblank->pipe;
286 unsigned long irqflags;
288 if (!dev->vblank_disable_allowed)
291 spin_lock_irqsave(&dev->vbl_lock, irqflags);
292 if (atomic_read(&vblank->refcount) == 0 && vblank->enabled) {
293 DRM_DEBUG_VBLANK("disabling vblank on crtc %u\n", pipe);
294 vblank_disable_and_save(dev, pipe);
296 spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
300 * drm_vblank_cleanup - cleanup vblank support
303 * This function cleans up any resources allocated in drm_vblank_init.
305 void drm_vblank_cleanup(struct drm_device *dev)
309 /* Bail if the driver didn't call drm_vblank_init() */
310 if (dev->num_crtcs == 0)
313 for (pipe = 0; pipe < dev->num_crtcs; pipe++) {
314 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
316 WARN_ON(vblank->enabled &&
317 drm_core_check_feature(dev, DRIVER_MODESET));
319 del_timer_sync(&vblank->disable_timer);
326 EXPORT_SYMBOL(drm_vblank_cleanup);
329 * drm_vblank_init - initialize vblank support
331 * @num_crtcs: number of CRTCs supported by @dev
333 * This function initializes vblank support for @num_crtcs display pipelines.
336 * Zero on success or a negative error code on failure.
338 int drm_vblank_init(struct drm_device *dev, unsigned int num_crtcs)
343 lockinit(&dev->vbl_lock, "drmvbl", 0, LK_CANRECURSE);
344 lockinit(&dev->vblank_time_lock, "drmvtl", 0, LK_CANRECURSE);
346 dev->num_crtcs = num_crtcs;
348 dev->vblank = kcalloc(num_crtcs, sizeof(*dev->vblank), GFP_KERNEL);
352 for (i = 0; i < num_crtcs; i++) {
353 struct drm_vblank_crtc *vblank = &dev->vblank[i];
357 init_waitqueue_head(&vblank->queue);
358 setup_timer(&vblank->disable_timer, vblank_disable_fn,
359 (unsigned long)vblank);
362 DRM_INFO("Supports vblank timestamp caching Rev 2 (21.10.2013).\n");
364 /* Driver specific high-precision vblank timestamping supported? */
365 if (dev->driver->get_vblank_timestamp)
366 DRM_INFO("Driver supports precise vblank timestamp query.\n");
368 DRM_INFO("No driver support for vblank timestamp query.\n");
370 /* Must have precise timestamping for reliable vblank instant disable */
371 if (dev->vblank_disable_immediate && !dev->driver->get_vblank_timestamp) {
372 dev->vblank_disable_immediate = false;
373 DRM_INFO("Setting vblank_disable_immediate to false because "
374 "get_vblank_timestamp == NULL\n");
377 dev->vblank_disable_allowed = false;
385 EXPORT_SYMBOL(drm_vblank_init);
388 static void drm_irq_vgaarb_nokms(void *cookie, bool state)
390 struct drm_device *dev = cookie;
392 if (dev->driver->vgaarb_irq) {
393 dev->driver->vgaarb_irq(dev, state);
397 if (!dev->irq_enabled)
401 if (dev->driver->irq_uninstall)
402 dev->driver->irq_uninstall(dev);
404 if (dev->driver->irq_preinstall)
405 dev->driver->irq_preinstall(dev);
406 if (dev->driver->irq_postinstall)
407 dev->driver->irq_postinstall(dev);
413 * drm_irq_install - install IRQ handler
415 * @irq: IRQ number to install the handler for
417 * Initializes the IRQ related data. Installs the handler, calling the driver
418 * irq_preinstall() and irq_postinstall() functions before and after the
421 * This is the simplified helper interface provided for drivers with no special
422 * needs. Drivers which need to install interrupt handlers for multiple
423 * interrupts must instead set drm_device->irq_enabled to signal the DRM core
424 * that vblank interrupts are available.
427 * Zero on success or a negative error code on failure.
429 int drm_irq_install(struct drm_device *dev, int irq)
433 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
439 /* Driver must have been initialized */
440 if (!dev->dev_private)
443 if (dev->irq_enabled)
445 dev->irq_enabled = true;
447 DRM_DEBUG("irq=%d\n", irq);
449 /* Before installing handler */
450 if (dev->driver->irq_preinstall)
451 dev->driver->irq_preinstall(dev);
453 /* Install handler */
454 ret = -bus_setup_intr(dev->dev, dev->irqr, INTR_MPSAFE,
455 dev->driver->irq_handler, dev, &dev->irqh, &dev->irq_lock);
458 dev->irq_enabled = false;
462 /* After installing handler */
463 if (dev->driver->irq_postinstall)
464 ret = dev->driver->irq_postinstall(dev);
467 dev->irq_enabled = false;
468 bus_teardown_intr(dev->dev, dev->irqr, dev->irqh);
475 EXPORT_SYMBOL(drm_irq_install);
478 * drm_irq_uninstall - uninstall the IRQ handler
481 * Calls the driver's irq_uninstall() function and unregisters the IRQ handler.
482 * This should only be called by drivers which used drm_irq_install() to set up
483 * their interrupt handler. Other drivers must only reset
484 * drm_device->irq_enabled to false.
486 * Note that for kernel modesetting drivers it is a bug if this function fails.
487 * The sanity checks are only to catch buggy user modesetting drivers which call
488 * the same function through an ioctl.
491 * Zero on success or a negative error code on failure.
493 int drm_irq_uninstall(struct drm_device *dev)
495 unsigned long irqflags;
499 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
502 irq_enabled = dev->irq_enabled;
503 dev->irq_enabled = false;
506 * Wake up any waiters so they don't hang. This is just to paper over
507 * isssues for UMS drivers which aren't in full control of their
508 * vblank/irq handling. KMS drivers must ensure that vblanks are all
509 * disabled when uninstalling the irq handler.
511 if (dev->num_crtcs) {
512 spin_lock_irqsave(&dev->vbl_lock, irqflags);
513 for (i = 0; i < dev->num_crtcs; i++) {
514 struct drm_vblank_crtc *vblank = &dev->vblank[i];
516 if (!vblank->enabled)
519 WARN_ON(drm_core_check_feature(dev, DRIVER_MODESET));
521 vblank_disable_and_save(dev, i);
522 wake_up(&vblank->queue);
524 spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
530 DRM_DEBUG("irq=%d\n", dev->irq);
532 if (dev->driver->irq_uninstall)
533 dev->driver->irq_uninstall(dev);
535 bus_teardown_intr(dev->dev, dev->irqr, dev->irqh);
539 EXPORT_SYMBOL(drm_irq_uninstall);
544 * \param inode device inode.
545 * \param file_priv DRM file private.
546 * \param cmd command.
547 * \param arg user argument, pointing to a drm_control structure.
548 * \return zero on success or a negative number on failure.
550 * Calls irq_install() or irq_uninstall() according to \p arg.
552 int drm_control(struct drm_device *dev, void *data,
553 struct drm_file *file_priv)
555 struct drm_control *ctl = data;
558 /* if we haven't irq we fallback for compatibility reasons -
559 * this used to be a separate function in drm_dma.h
562 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
564 if (drm_core_check_feature(dev, DRIVER_MODESET))
566 /* UMS was only ever support on pci devices. */
567 if (WARN_ON(!dev->pdev))
571 case DRM_INST_HANDLER:
574 if (dev->if_version < DRM_IF_VERSION(1, 2) &&
577 mutex_lock(&dev->struct_mutex);
578 ret = drm_irq_install(dev, irq);
579 mutex_unlock(&dev->struct_mutex);
582 case DRM_UNINST_HANDLER:
583 mutex_lock(&dev->struct_mutex);
584 ret = drm_irq_uninstall(dev);
585 mutex_unlock(&dev->struct_mutex);
594 * drm_calc_timestamping_constants - calculate vblank timestamp constants
595 * @crtc: drm_crtc whose timestamp constants should be updated.
596 * @mode: display mode containing the scanout timings
598 * Calculate and store various constants which are later
599 * needed by vblank and swap-completion timestamping, e.g,
600 * by drm_calc_vbltimestamp_from_scanoutpos(). They are
601 * derived from CRTC's true scanout timing, so they take
602 * things like panel scaling or other adjustments into account.
604 void drm_calc_timestamping_constants(struct drm_crtc *crtc,
605 const struct drm_display_mode *mode)
607 struct drm_device *dev = crtc->dev;
608 unsigned int pipe = drm_crtc_index(crtc);
609 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
610 int linedur_ns = 0, framedur_ns = 0;
611 int dotclock = mode->crtc_clock;
616 if (WARN_ON(pipe >= dev->num_crtcs))
619 /* Valid dotclock? */
621 int frame_size = mode->crtc_htotal * mode->crtc_vtotal;
624 * Convert scanline length in pixels and video
625 * dot clock to line duration and frame duration
628 linedur_ns = div_u64((u64) mode->crtc_htotal * 1000000, dotclock);
629 framedur_ns = div_u64((u64) frame_size * 1000000, dotclock);
632 * Fields of interlaced scanout modes are only half a frame duration.
634 if (mode->flags & DRM_MODE_FLAG_INTERLACE)
637 DRM_ERROR("crtc %u: Can't calculate constants, dotclock = 0!\n",
640 vblank->linedur_ns = linedur_ns;
641 vblank->framedur_ns = framedur_ns;
643 DRM_DEBUG("crtc %u: hwmode: htotal %d, vtotal %d, vdisplay %d\n",
644 crtc->base.id, mode->crtc_htotal,
645 mode->crtc_vtotal, mode->crtc_vdisplay);
646 DRM_DEBUG("crtc %u: clock %d kHz framedur %d linedur %d\n",
647 crtc->base.id, dotclock, framedur_ns, linedur_ns);
649 EXPORT_SYMBOL(drm_calc_timestamping_constants);
652 * drm_calc_vbltimestamp_from_scanoutpos - precise vblank timestamp helper
654 * @pipe: index of CRTC whose vblank timestamp to retrieve
655 * @max_error: Desired maximum allowable error in timestamps (nanosecs)
656 * On return contains true maximum error of timestamp
657 * @vblank_time: Pointer to struct timeval which should receive the timestamp
658 * @flags: Flags to pass to driver:
660 * DRM_CALLED_FROM_VBLIRQ = If function is called from vbl IRQ handler
661 * @mode: mode which defines the scanout timings
663 * Implements calculation of exact vblank timestamps from given drm_display_mode
664 * timings and current video scanout position of a CRTC. This can be called from
665 * within get_vblank_timestamp() implementation of a kms driver to implement the
666 * actual timestamping.
668 * Should return timestamps conforming to the OML_sync_control OpenML
669 * extension specification. The timestamp corresponds to the end of
670 * the vblank interval, aka start of scanout of topmost-leftmost display
671 * pixel in the following video frame.
673 * Requires support for optional dev->driver->get_scanout_position()
674 * in kms driver, plus a bit of setup code to provide a drm_display_mode
675 * that corresponds to the true scanout timing.
677 * The current implementation only handles standard video modes. It
678 * returns as no operation if a doublescan or interlaced video mode is
679 * active. Higher level code is expected to handle this.
682 * Negative value on error, failure or if not supported in current
685 * -EINVAL - Invalid CRTC.
686 * -EAGAIN - Temporary unavailable, e.g., called before initial modeset.
687 * -ENOTSUPP - Function not supported in current display mode.
688 * -EIO - Failed, e.g., due to failed scanout position query.
690 * Returns or'ed positive status flags on success:
692 * DRM_VBLANKTIME_SCANOUTPOS_METHOD - Signal this method used for timestamping.
693 * DRM_VBLANKTIME_INVBL - Timestamp taken while scanout was in vblank interval.
696 int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
699 struct timeval *vblank_time,
701 const struct drm_display_mode *mode)
703 struct timeval tv_etime;
704 ktime_t stime, etime;
705 unsigned int vbl_status;
706 int ret = DRM_VBLANKTIME_SCANOUTPOS_METHOD;
708 int delta_ns, duration_ns;
710 if (pipe >= dev->num_crtcs) {
711 DRM_ERROR("Invalid crtc %u\n", pipe);
715 /* Scanout position query not supported? Should not happen. */
716 if (!dev->driver->get_scanout_position) {
717 DRM_ERROR("Called from driver w/o get_scanout_position()!?\n");
721 /* If mode timing undefined, just return as no-op:
722 * Happens during initial modesetting of a crtc.
724 if (mode->crtc_clock == 0) {
725 DRM_DEBUG_VBLANK("crtc %u: Noop due to uninitialized mode.\n", pipe);
729 /* Get current scanout position with system timestamp.
730 * Repeat query up to DRM_TIMESTAMP_MAXRETRIES times
731 * if single query takes longer than max_error nanoseconds.
733 * This guarantees a tight bound on maximum error if
734 * code gets preempted or delayed for some reason.
736 for (i = 0; i < DRM_TIMESTAMP_MAXRETRIES; i++) {
738 * Get vertical and horizontal scanout position vpos, hpos,
739 * and bounding timestamps stime, etime, pre/post query.
741 vbl_status = dev->driver->get_scanout_position(dev, pipe, flags,
746 /* Return as no-op if scanout query unsupported or failed. */
747 if (!(vbl_status & DRM_SCANOUTPOS_VALID)) {
748 DRM_DEBUG_VBLANK("crtc %u : scanoutpos query failed [0x%x].\n",
753 /* Compute uncertainty in timestamp of scanout position query. */
754 duration_ns = ktime_to_ns(etime) - ktime_to_ns(stime);
756 /* Accept result with < max_error nsecs timing uncertainty. */
757 if (duration_ns <= *max_error)
761 /* Noisy system timing? */
762 if (i == DRM_TIMESTAMP_MAXRETRIES) {
763 DRM_DEBUG_VBLANK("crtc %u: Noisy timestamp %d us > %d us [%d reps].\n",
764 pipe, duration_ns/1000, *max_error/1000, i);
767 /* Return upper bound of timestamp precision error. */
768 *max_error = duration_ns;
770 /* Check if in vblank area:
771 * vpos is >=0 in video scanout area, but negative
772 * within vblank area, counting down the number of lines until
775 if (vbl_status & DRM_SCANOUTPOS_IN_VBLANK)
776 ret |= DRM_VBLANKTIME_IN_VBLANK;
778 /* Convert scanout position into elapsed time at raw_time query
779 * since start of scanout at first display scanline. delta_ns
780 * can be negative if start of scanout hasn't happened yet.
782 delta_ns = div_s64(1000000LL * (vpos * mode->crtc_htotal + hpos),
785 if (!drm_timestamp_monotonic)
786 etime = ktime_mono_to_real(etime);
788 /* save this only for debugging purposes */
789 tv_etime = ktime_to_timeval(etime);
790 /* Subtract time delta from raw timestamp to get final
791 * vblank_time timestamp for end of vblank.
794 etime = ktime_add_ns(etime, -delta_ns);
796 etime = ktime_sub_ns(etime, delta_ns);
797 *vblank_time = ktime_to_timeval(etime);
799 DRM_DEBUG_VBLANK("crtc %u : v 0x%x p(%d,%d)@ %ld.%ld -> %ld.%ld [e %d us, %d rep]\n",
800 pipe, vbl_status, hpos, vpos,
801 (long)tv_etime.tv_sec, (long)tv_etime.tv_usec,
802 (long)vblank_time->tv_sec, (long)vblank_time->tv_usec,
803 duration_ns/1000, i);
807 EXPORT_SYMBOL(drm_calc_vbltimestamp_from_scanoutpos);
809 static struct timeval get_drm_timestamp(void)
813 now = drm_timestamp_monotonic ? ktime_get() : ktime_get_real();
814 return ktime_to_timeval(now);
818 * drm_get_last_vbltimestamp - retrieve raw timestamp for the most recent
821 * @pipe: index of CRTC whose vblank timestamp to retrieve
822 * @tvblank: Pointer to target struct timeval which should receive the timestamp
823 * @flags: Flags to pass to driver:
825 * DRM_CALLED_FROM_VBLIRQ = If function is called from vbl IRQ handler
827 * Fetches the system timestamp corresponding to the time of the most recent
828 * vblank interval on specified CRTC. May call into kms-driver to
829 * compute the timestamp with a high-precision GPU specific method.
831 * Returns zero if timestamp originates from uncorrected do_gettimeofday()
832 * call, i.e., it isn't very precisely locked to the true vblank.
835 * True if timestamp is considered to be very precise, false otherwise.
838 drm_get_last_vbltimestamp(struct drm_device *dev, unsigned int pipe,
839 struct timeval *tvblank, unsigned flags)
843 /* Define requested maximum error on timestamps (nanoseconds). */
844 int max_error = (int) drm_timestamp_precision * 1000;
846 /* Query driver if possible and precision timestamping enabled. */
847 if (dev->driver->get_vblank_timestamp && (max_error > 0)) {
848 ret = dev->driver->get_vblank_timestamp(dev, pipe, &max_error,
854 /* GPU high precision timestamp query unsupported or failed.
855 * Return current monotonic/gettimeofday timestamp as best estimate.
857 *tvblank = get_drm_timestamp();
863 * drm_vblank_count - retrieve "cooked" vblank counter value
865 * @pipe: index of CRTC for which to retrieve the counter
867 * Fetches the "cooked" vblank count value that represents the number of
868 * vblank events since the system was booted, including lost events due to
869 * modesetting activity.
871 * This is the legacy version of drm_crtc_vblank_count().
874 * The software vblank counter.
876 u32 drm_vblank_count(struct drm_device *dev, unsigned int pipe)
878 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
880 if (WARN_ON(pipe >= dev->num_crtcs))
883 return vblank->count;
885 EXPORT_SYMBOL(drm_vblank_count);
888 * drm_crtc_vblank_count - retrieve "cooked" vblank counter value
889 * @crtc: which counter to retrieve
891 * Fetches the "cooked" vblank count value that represents the number of
892 * vblank events since the system was booted, including lost events due to
893 * modesetting activity.
895 * This is the native KMS version of drm_vblank_count().
898 * The software vblank counter.
900 u32 drm_crtc_vblank_count(struct drm_crtc *crtc)
902 return drm_vblank_count(crtc->dev, drm_crtc_index(crtc));
904 EXPORT_SYMBOL(drm_crtc_vblank_count);
907 * drm_vblank_count_and_time - retrieve "cooked" vblank counter value and the
908 * system timestamp corresponding to that vblank counter value.
910 * @pipe: index of CRTC whose counter to retrieve
911 * @vblanktime: Pointer to struct timeval to receive the vblank timestamp.
913 * Fetches the "cooked" vblank count value that represents the number of
914 * vblank events since the system was booted, including lost events due to
915 * modesetting activity. Returns corresponding system timestamp of the time
916 * of the vblank interval that corresponds to the current vblank counter value.
918 * This is the legacy version of drm_crtc_vblank_count_and_time().
920 u32 drm_vblank_count_and_time(struct drm_device *dev, unsigned int pipe,
921 struct timeval *vblanktime)
923 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
924 int count = DRM_TIMESTAMP_MAXRETRIES;
927 if (WARN_ON(pipe >= dev->num_crtcs))
931 * Vblank timestamps are read lockless. To ensure consistency the vblank
932 * counter is rechecked and ordering is ensured using memory barriers.
933 * This works like a seqlock. The write-side barriers are in store_vblank.
936 cur_vblank = vblank->count;
938 *vblanktime = vblanktimestamp(dev, pipe, cur_vblank);
940 } while (cur_vblank != vblank->count && --count > 0);
944 EXPORT_SYMBOL(drm_vblank_count_and_time);
947 * drm_crtc_vblank_count_and_time - retrieve "cooked" vblank counter value
948 * and the system timestamp corresponding to that vblank counter value
949 * @crtc: which counter to retrieve
950 * @vblanktime: Pointer to struct timeval to receive the vblank timestamp.
952 * Fetches the "cooked" vblank count value that represents the number of
953 * vblank events since the system was booted, including lost events due to
954 * modesetting activity. Returns corresponding system timestamp of the time
955 * of the vblank interval that corresponds to the current vblank counter value.
957 * This is the native KMS version of drm_vblank_count_and_time().
959 u32 drm_crtc_vblank_count_and_time(struct drm_crtc *crtc,
960 struct timeval *vblanktime)
962 return drm_vblank_count_and_time(crtc->dev, drm_crtc_index(crtc),
965 EXPORT_SYMBOL(drm_crtc_vblank_count_and_time);
967 static void send_vblank_event(struct drm_device *dev,
968 struct drm_pending_vblank_event *e,
969 unsigned long seq, struct timeval *now)
971 assert_spin_locked(&dev->event_lock);
973 e->event.sequence = seq;
974 e->event.tv_sec = now->tv_sec;
975 e->event.tv_usec = now->tv_usec;
977 list_add_tail(&e->base.link,
978 &e->base.file_priv->event_list);
979 wake_up_interruptible(&e->base.file_priv->event_wait);
981 KNOTE(&e->base.file_priv->dkq.ki_note, 0);
983 trace_drm_vblank_event_delivered(e->base.pid, e->pipe,
988 * drm_arm_vblank_event - arm vblank event after pageflip
991 * @e: the event to prepare to send
993 * A lot of drivers need to generate vblank events for the very next vblank
994 * interrupt. For example when the page flip interrupt happens when the page
995 * flip gets armed, but not when it actually executes within the next vblank
996 * period. This helper function implements exactly the required vblank arming
999 * Caller must hold event lock. Caller must also hold a vblank reference for
1000 * the event @e, which will be dropped when the next vblank arrives.
1002 * This is the legacy version of drm_crtc_arm_vblank_event().
1004 void drm_arm_vblank_event(struct drm_device *dev, unsigned int pipe,
1005 struct drm_pending_vblank_event *e)
1007 assert_spin_locked(&dev->event_lock);
1010 e->event.sequence = drm_vblank_count(dev, pipe);
1011 list_add_tail(&e->base.link, &dev->vblank_event_list);
1013 EXPORT_SYMBOL(drm_arm_vblank_event);
1016 * drm_crtc_arm_vblank_event - arm vblank event after pageflip
1017 * @crtc: the source CRTC of the vblank event
1018 * @e: the event to send
1020 * A lot of drivers need to generate vblank events for the very next vblank
1021 * interrupt. For example when the page flip interrupt happens when the page
1022 * flip gets armed, but not when it actually executes within the next vblank
1023 * period. This helper function implements exactly the required vblank arming
1026 * Caller must hold event lock. Caller must also hold a vblank reference for
1027 * the event @e, which will be dropped when the next vblank arrives.
1029 * This is the native KMS version of drm_arm_vblank_event().
1031 void drm_crtc_arm_vblank_event(struct drm_crtc *crtc,
1032 struct drm_pending_vblank_event *e)
1034 drm_arm_vblank_event(crtc->dev, drm_crtc_index(crtc), e);
1036 EXPORT_SYMBOL(drm_crtc_arm_vblank_event);
1039 * drm_send_vblank_event - helper to send vblank event after pageflip
1042 * @e: the event to send
1044 * Updates sequence # and timestamp on event, and sends it to userspace.
1045 * Caller must hold event lock.
1047 * This is the legacy version of drm_crtc_send_vblank_event().
1049 void drm_send_vblank_event(struct drm_device *dev, unsigned int pipe,
1050 struct drm_pending_vblank_event *e)
1055 if (dev->num_crtcs > 0) {
1056 seq = drm_vblank_count_and_time(dev, pipe, &now);
1060 now = get_drm_timestamp();
1063 send_vblank_event(dev, e, seq, &now);
1065 EXPORT_SYMBOL(drm_send_vblank_event);
1068 * drm_crtc_send_vblank_event - helper to send vblank event after pageflip
1069 * @crtc: the source CRTC of the vblank event
1070 * @e: the event to send
1072 * Updates sequence # and timestamp on event, and sends it to userspace.
1073 * Caller must hold event lock.
1075 * This is the native KMS version of drm_send_vblank_event().
1077 void drm_crtc_send_vblank_event(struct drm_crtc *crtc,
1078 struct drm_pending_vblank_event *e)
1080 drm_send_vblank_event(crtc->dev, drm_crtc_index(crtc), e);
1082 EXPORT_SYMBOL(drm_crtc_send_vblank_event);
1085 * drm_vblank_enable - enable the vblank interrupt on a CRTC
1090 * Zero on success or a negative error code on failure.
1092 static int drm_vblank_enable(struct drm_device *dev, unsigned int pipe)
1094 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
1097 assert_spin_locked(&dev->vbl_lock);
1099 lockmgr(&dev->vblank_time_lock, LK_EXCLUSIVE);
1101 if (!vblank->enabled) {
1103 * Enable vblank irqs under vblank_time_lock protection.
1104 * All vblank count & timestamp updates are held off
1105 * until we are done reinitializing master counter and
1106 * timestamps. Filtercode in drm_handle_vblank() will
1107 * prevent double-accounting of same vblank interval.
1109 ret = dev->driver->enable_vblank(dev, pipe);
1110 DRM_DEBUG_VBLANK("enabling vblank on crtc %u, ret: %d\n", pipe, ret);
1112 atomic_dec(&vblank->refcount);
1114 vblank->enabled = true;
1115 drm_update_vblank_count(dev, pipe, 0);
1119 lockmgr(&dev->vblank_time_lock, LK_RELEASE);
1125 * drm_vblank_get - get a reference count on vblank events
1127 * @pipe: index of CRTC to own
1129 * Acquire a reference count on vblank events to avoid having them disabled
1132 * This is the legacy version of drm_crtc_vblank_get().
1135 * Zero on success or a negative error code on failure.
1137 int drm_vblank_get(struct drm_device *dev, unsigned int pipe)
1139 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
1140 unsigned long irqflags;
1143 if (!dev->num_crtcs)
1146 if (WARN_ON(pipe >= dev->num_crtcs))
1149 spin_lock_irqsave(&dev->vbl_lock, irqflags);
1150 /* Going from 0->1 means we have to enable interrupts again */
1151 if (atomic_add_return(1, &vblank->refcount) == 1) {
1152 ret = drm_vblank_enable(dev, pipe);
1154 if (!vblank->enabled) {
1155 atomic_dec(&vblank->refcount);
1159 spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
1163 EXPORT_SYMBOL(drm_vblank_get);
1166 * drm_crtc_vblank_get - get a reference count on vblank events
1167 * @crtc: which CRTC to own
1169 * Acquire a reference count on vblank events to avoid having them disabled
1172 * This is the native kms version of drm_vblank_get().
1175 * Zero on success or a negative error code on failure.
1177 int drm_crtc_vblank_get(struct drm_crtc *crtc)
1179 return drm_vblank_get(crtc->dev, drm_crtc_index(crtc));
1181 EXPORT_SYMBOL(drm_crtc_vblank_get);
1184 * drm_vblank_put - release ownership of vblank events
1186 * @pipe: index of CRTC to release
1188 * Release ownership of a given vblank counter, turning off interrupts
1189 * if possible. Disable interrupts after drm_vblank_offdelay milliseconds.
1191 * This is the legacy version of drm_crtc_vblank_put().
1193 void drm_vblank_put(struct drm_device *dev, unsigned int pipe)
1195 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
1197 if (WARN_ON(pipe >= dev->num_crtcs))
1200 if (WARN_ON(atomic_read(&vblank->refcount) == 0))
1203 /* Last user schedules interrupt disable */
1204 if (atomic_dec_and_test(&vblank->refcount)) {
1205 if (drm_vblank_offdelay == 0)
1207 else if (dev->vblank_disable_immediate || drm_vblank_offdelay < 0)
1208 vblank_disable_fn((unsigned long)vblank);
1210 mod_timer(&vblank->disable_timer,
1211 jiffies + ((drm_vblank_offdelay * HZ)/1000));
1214 EXPORT_SYMBOL(drm_vblank_put);
1217 * drm_crtc_vblank_put - give up ownership of vblank events
1218 * @crtc: which counter to give up
1220 * Release ownership of a given vblank counter, turning off interrupts
1221 * if possible. Disable interrupts after drm_vblank_offdelay milliseconds.
1223 * This is the native kms version of drm_vblank_put().
1225 void drm_crtc_vblank_put(struct drm_crtc *crtc)
1227 drm_vblank_put(crtc->dev, drm_crtc_index(crtc));
1229 EXPORT_SYMBOL(drm_crtc_vblank_put);
1232 * drm_wait_one_vblank - wait for one vblank
1236 * This waits for one vblank to pass on @pipe, using the irq driver interfaces.
1237 * It is a failure to call this when the vblank irq for @pipe is disabled, e.g.
1238 * due to lack of driver support or because the crtc is off.
1240 void drm_wait_one_vblank(struct drm_device *dev, unsigned int pipe)
1242 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
1246 if (WARN_ON(pipe >= dev->num_crtcs))
1249 ret = drm_vblank_get(dev, pipe);
1250 if (WARN(ret, "vblank not available on crtc %i, ret=%i\n", pipe, ret))
1253 last = drm_vblank_count(dev, pipe);
1255 ret = wait_event_timeout(vblank->queue,
1256 last != drm_vblank_count(dev, pipe),
1257 msecs_to_jiffies(100));
1259 WARN(ret == 0, "vblank wait timed out on crtc %i\n", pipe);
1261 drm_vblank_put(dev, pipe);
1263 EXPORT_SYMBOL(drm_wait_one_vblank);
1266 * drm_crtc_wait_one_vblank - wait for one vblank
1269 * This waits for one vblank to pass on @crtc, using the irq driver interfaces.
1270 * It is a failure to call this when the vblank irq for @crtc is disabled, e.g.
1271 * due to lack of driver support or because the crtc is off.
1273 void drm_crtc_wait_one_vblank(struct drm_crtc *crtc)
1275 drm_wait_one_vblank(crtc->dev, drm_crtc_index(crtc));
1277 EXPORT_SYMBOL(drm_crtc_wait_one_vblank);
1280 * drm_vblank_off - disable vblank events on a CRTC
1284 * Drivers can use this function to shut down the vblank interrupt handling when
1285 * disabling a crtc. This function ensures that the latest vblank frame count is
1286 * stored so that drm_vblank_on() can restore it again.
1288 * Drivers must use this function when the hardware vblank counter can get
1289 * reset, e.g. when suspending.
1291 * This is the legacy version of drm_crtc_vblank_off().
1293 void drm_vblank_off(struct drm_device *dev, unsigned int pipe)
1295 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
1296 struct drm_pending_vblank_event *e, *t;
1298 unsigned long irqflags;
1301 if (WARN_ON(pipe >= dev->num_crtcs))
1304 spin_lock_irqsave(&dev->event_lock, irqflags);
1306 lockmgr(&dev->vbl_lock, LK_EXCLUSIVE);
1307 vblank_disable_and_save(dev, pipe);
1308 wake_up(&vblank->queue);
1311 * Prevent subsequent drm_vblank_get() from re-enabling
1312 * the vblank interrupt by bumping the refcount.
1314 if (!vblank->inmodeset) {
1315 atomic_inc(&vblank->refcount);
1316 vblank->inmodeset = 1;
1318 lockmgr(&dev->vbl_lock, LK_RELEASE);
1320 /* Send any queued vblank events, lest the natives grow disquiet */
1321 seq = drm_vblank_count_and_time(dev, pipe, &now);
1323 list_for_each_entry_safe(e, t, &dev->vblank_event_list, base.link) {
1324 if (e->pipe != pipe)
1326 DRM_DEBUG_VBLANK("Sending premature vblank event on disable: \
1327 wanted %d, current %d\n",
1328 e->event.sequence, seq);
1329 list_del(&e->base.link);
1330 drm_vblank_put(dev, pipe);
1331 send_vblank_event(dev, e, seq, &now);
1333 spin_unlock_irqrestore(&dev->event_lock, irqflags);
1335 EXPORT_SYMBOL(drm_vblank_off);
1338 * drm_crtc_vblank_off - disable vblank events on a CRTC
1339 * @crtc: CRTC in question
1341 * Drivers can use this function to shut down the vblank interrupt handling when
1342 * disabling a crtc. This function ensures that the latest vblank frame count is
1343 * stored so that drm_vblank_on can restore it again.
1345 * Drivers must use this function when the hardware vblank counter can get
1346 * reset, e.g. when suspending.
1348 * This is the native kms version of drm_vblank_off().
1350 void drm_crtc_vblank_off(struct drm_crtc *crtc)
1352 drm_vblank_off(crtc->dev, drm_crtc_index(crtc));
1354 EXPORT_SYMBOL(drm_crtc_vblank_off);
1357 * drm_crtc_vblank_reset - reset vblank state to off on a CRTC
1358 * @crtc: CRTC in question
1360 * Drivers can use this function to reset the vblank state to off at load time.
1361 * Drivers should use this together with the drm_crtc_vblank_off() and
1362 * drm_crtc_vblank_on() functions. The difference compared to
1363 * drm_crtc_vblank_off() is that this function doesn't save the vblank counter
1364 * and hence doesn't need to call any driver hooks.
1366 void drm_crtc_vblank_reset(struct drm_crtc *crtc)
1368 struct drm_device *dev = crtc->dev;
1369 unsigned long irqflags;
1370 unsigned int pipe = drm_crtc_index(crtc);
1371 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
1373 spin_lock_irqsave(&dev->vbl_lock, irqflags);
1375 * Prevent subsequent drm_vblank_get() from enabling the vblank
1376 * interrupt by bumping the refcount.
1378 if (!vblank->inmodeset) {
1379 atomic_inc(&vblank->refcount);
1380 vblank->inmodeset = 1;
1382 spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
1384 WARN_ON(!list_empty(&dev->vblank_event_list));
1386 EXPORT_SYMBOL(drm_crtc_vblank_reset);
1389 * drm_vblank_on - enable vblank events on a CRTC
1393 * This functions restores the vblank interrupt state captured with
1394 * drm_vblank_off() again. Note that calls to drm_vblank_on() and
1395 * drm_vblank_off() can be unbalanced and so can also be unconditionally called
1396 * in driver load code to reflect the current hardware state of the crtc.
1398 * This is the legacy version of drm_crtc_vblank_on().
1400 void drm_vblank_on(struct drm_device *dev, unsigned int pipe)
1402 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
1403 unsigned long irqflags;
1405 if (WARN_ON(pipe >= dev->num_crtcs))
1408 spin_lock_irqsave(&dev->vbl_lock, irqflags);
1409 /* Drop our private "prevent drm_vblank_get" refcount */
1410 if (vblank->inmodeset) {
1411 atomic_dec(&vblank->refcount);
1412 vblank->inmodeset = 0;
1415 drm_reset_vblank_timestamp(dev, pipe);
1418 * re-enable interrupts if there are users left, or the
1419 * user wishes vblank interrupts to be enabled all the time.
1421 if (atomic_read(&vblank->refcount) != 0 ||
1422 (!dev->vblank_disable_immediate && drm_vblank_offdelay == 0))
1423 WARN_ON(drm_vblank_enable(dev, pipe));
1424 spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
1426 EXPORT_SYMBOL(drm_vblank_on);
1429 * drm_crtc_vblank_on - enable vblank events on a CRTC
1430 * @crtc: CRTC in question
1432 * This functions restores the vblank interrupt state captured with
1433 * drm_vblank_off() again. Note that calls to drm_vblank_on() and
1434 * drm_vblank_off() can be unbalanced and so can also be unconditionally called
1435 * in driver load code to reflect the current hardware state of the crtc.
1437 * This is the native kms version of drm_vblank_on().
1439 void drm_crtc_vblank_on(struct drm_crtc *crtc)
1441 drm_vblank_on(crtc->dev, drm_crtc_index(crtc));
1443 EXPORT_SYMBOL(drm_crtc_vblank_on);
1446 * drm_vblank_pre_modeset - account for vblanks across mode sets
1450 * Account for vblank events across mode setting events, which will likely
1451 * reset the hardware frame counter.
1453 * This is done by grabbing a temporary vblank reference to ensure that the
1454 * vblank interrupt keeps running across the modeset sequence. With this the
1455 * software-side vblank frame counting will ensure that there are no jumps or
1458 * Unfortunately this approach is racy and also doesn't work when the vblank
1459 * interrupt stops running, e.g. across system suspend resume. It is therefore
1460 * highly recommended that drivers use the newer drm_vblank_off() and
1461 * drm_vblank_on() instead. drm_vblank_pre_modeset() only works correctly when
1462 * using "cooked" software vblank frame counters and not relying on any hardware
1465 * Drivers must call drm_vblank_post_modeset() when re-enabling the same crtc
1468 void drm_vblank_pre_modeset(struct drm_device *dev, unsigned int pipe)
1470 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
1472 /* vblank is not initialized (IRQ not installed ?), or has been freed */
1473 if (!dev->num_crtcs)
1476 if (WARN_ON(pipe >= dev->num_crtcs))
1480 * To avoid all the problems that might happen if interrupts
1481 * were enabled/disabled around or between these calls, we just
1482 * have the kernel take a reference on the CRTC (just once though
1483 * to avoid corrupting the count if multiple, mismatch calls occur),
1484 * so that interrupts remain enabled in the interim.
1486 if (!vblank->inmodeset) {
1487 vblank->inmodeset = 0x1;
1488 if (drm_vblank_get(dev, pipe) == 0)
1489 vblank->inmodeset |= 0x2;
1492 EXPORT_SYMBOL(drm_vblank_pre_modeset);
1495 * drm_vblank_post_modeset - undo drm_vblank_pre_modeset changes
1499 * This function again drops the temporary vblank reference acquired in
1500 * drm_vblank_pre_modeset.
1502 void drm_vblank_post_modeset(struct drm_device *dev, unsigned int pipe)
1504 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
1505 unsigned long irqflags;
1507 /* vblank is not initialized (IRQ not installed ?), or has been freed */
1508 if (!dev->num_crtcs)
1511 if (WARN_ON(pipe >= dev->num_crtcs))
1514 if (vblank->inmodeset) {
1515 spin_lock_irqsave(&dev->vbl_lock, irqflags);
1516 dev->vblank_disable_allowed = true;
1517 spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
1519 if (vblank->inmodeset & 0x2)
1520 drm_vblank_put(dev, pipe);
1522 vblank->inmodeset = 0;
1525 EXPORT_SYMBOL(drm_vblank_post_modeset);
1528 * drm_modeset_ctl - handle vblank event counter changes across mode switch
1529 * @DRM_IOCTL_ARGS: standard ioctl arguments
1531 * Applications should call the %_DRM_PRE_MODESET and %_DRM_POST_MODESET
1532 * ioctls around modesetting so that any lost vblank events are accounted for.
1534 * Generally the counter will reset across mode sets. If interrupts are
1535 * enabled around this call, we don't have to do anything since the counter
1536 * will have already been incremented.
1538 int drm_modeset_ctl(struct drm_device *dev, void *data,
1539 struct drm_file *file_priv)
1541 struct drm_modeset_ctl *modeset = data;
1544 /* If drm_vblank_init() hasn't been called yet, just no-op */
1545 if (!dev->num_crtcs)
1548 /* KMS drivers handle this internally */
1549 if (drm_core_check_feature(dev, DRIVER_MODESET))
1552 pipe = modeset->crtc;
1553 if (pipe >= dev->num_crtcs)
1556 switch (modeset->cmd) {
1557 case _DRM_PRE_MODESET:
1558 drm_vblank_pre_modeset(dev, pipe);
1560 case _DRM_POST_MODESET:
1561 drm_vblank_post_modeset(dev, pipe);
1570 #ifdef __DragonFly__
1572 * The Linux layer version of kfree() is a macro and can't be called
1573 * directly via a function pointer
1576 drm_vblank_event_destroy(struct drm_pending_event *e)
1582 static int drm_queue_vblank_event(struct drm_device *dev, unsigned int pipe,
1583 union drm_wait_vblank *vblwait,
1584 struct drm_file *file_priv)
1586 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
1587 struct drm_pending_vblank_event *e;
1589 unsigned long flags;
1593 e = kzalloc(sizeof(*e), GFP_KERNEL);
1600 e->base.pid = curproc->p_pid;
1601 e->event.base.type = DRM_EVENT_VBLANK;
1602 e->event.base.length = sizeof(e->event);
1603 e->event.user_data = vblwait->request.signal;
1604 e->base.event = &e->event.base;
1605 e->base.file_priv = file_priv;
1606 #ifdef __DragonFly__
1607 e->base.destroy = drm_vblank_event_destroy;
1609 e->base.destroy = (void (*) (struct drm_pending_event *)) kfree;
1612 spin_lock_irqsave(&dev->event_lock, flags);
1615 * drm_vblank_off() might have been called after we called
1616 * drm_vblank_get(). drm_vblank_off() holds event_lock
1617 * around the vblank disable, so no need for further locking.
1618 * The reference from drm_vblank_get() protects against
1619 * vblank disable from another source.
1621 if (!vblank->enabled) {
1626 if (file_priv->event_space < sizeof(e->event)) {
1631 file_priv->event_space -= sizeof(e->event);
1632 seq = drm_vblank_count_and_time(dev, pipe, &now);
1634 if ((vblwait->request.type & _DRM_VBLANK_NEXTONMISS) &&
1635 (seq - vblwait->request.sequence) <= (1 << 23)) {
1636 vblwait->request.sequence = seq + 1;
1637 vblwait->reply.sequence = vblwait->request.sequence;
1640 DRM_DEBUG_VBLANK("event on vblank count %d, current %d, crtc %u\n",
1641 vblwait->request.sequence, seq, pipe);
1643 trace_drm_vblank_event_queued(current->pid, pipe,
1644 vblwait->request.sequence);
1646 e->event.sequence = vblwait->request.sequence;
1647 if ((seq - vblwait->request.sequence) <= (1 << 23)) {
1648 drm_vblank_put(dev, pipe);
1649 send_vblank_event(dev, e, seq, &now);
1650 vblwait->reply.sequence = seq;
1652 /* drm_handle_vblank_events will call drm_vblank_put */
1653 list_add_tail(&e->base.link, &dev->vblank_event_list);
1654 vblwait->reply.sequence = vblwait->request.sequence;
1657 spin_unlock_irqrestore(&dev->event_lock, flags);
1662 spin_unlock_irqrestore(&dev->event_lock, flags);
1665 drm_vblank_put(dev, pipe);
1672 * \param inode device inode.
1673 * \param file_priv DRM file private.
1674 * \param cmd command.
1675 * \param data user argument, pointing to a drm_wait_vblank structure.
1676 * \return zero on success or a negative number on failure.
1678 * This function enables the vblank interrupt on the pipe requested, then
1679 * sleeps waiting for the requested sequence number to occur, and drops
1680 * the vblank interrupt refcount afterwards. (vblank IRQ disable follows that
1681 * after a timeout with no further vblank waits scheduled).
1683 int drm_wait_vblank(struct drm_device *dev, void *data,
1684 struct drm_file *file_priv)
1686 struct drm_vblank_crtc *vblank;
1687 union drm_wait_vblank *vblwait = data;
1689 unsigned int flags, seq, pipe, high_pipe;
1691 if (!dev->irq_enabled)
1694 if (vblwait->request.type & _DRM_VBLANK_SIGNAL)
1697 if (vblwait->request.type &
1698 ~(_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK |
1699 _DRM_VBLANK_HIGH_CRTC_MASK)) {
1700 DRM_ERROR("Unsupported type value 0x%x, supported mask 0x%x\n",
1701 vblwait->request.type,
1702 (_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK |
1703 _DRM_VBLANK_HIGH_CRTC_MASK));
1707 flags = vblwait->request.type & _DRM_VBLANK_FLAGS_MASK;
1708 high_pipe = (vblwait->request.type & _DRM_VBLANK_HIGH_CRTC_MASK);
1710 pipe = high_pipe >> _DRM_VBLANK_HIGH_CRTC_SHIFT;
1712 pipe = flags & _DRM_VBLANK_SECONDARY ? 1 : 0;
1713 if (pipe >= dev->num_crtcs)
1716 vblank = &dev->vblank[pipe];
1718 ret = drm_vblank_get(dev, pipe);
1720 DRM_DEBUG_VBLANK("failed to acquire vblank counter, %d\n", ret);
1723 seq = drm_vblank_count(dev, pipe);
1725 switch (vblwait->request.type & _DRM_VBLANK_TYPES_MASK) {
1726 case _DRM_VBLANK_RELATIVE:
1727 vblwait->request.sequence += seq;
1728 vblwait->request.type &= ~_DRM_VBLANK_RELATIVE;
1729 case _DRM_VBLANK_ABSOLUTE:
1736 if (flags & _DRM_VBLANK_EVENT) {
1737 /* must hold on to the vblank ref until the event fires
1738 * drm_vblank_put will be called asynchronously
1740 return drm_queue_vblank_event(dev, pipe, vblwait, file_priv);
1743 if ((flags & _DRM_VBLANK_NEXTONMISS) &&
1744 (seq - vblwait->request.sequence) <= (1<<23)) {
1745 vblwait->request.sequence = seq + 1;
1748 DRM_DEBUG_VBLANK("waiting on vblank count %d, crtc %u\n",
1749 vblwait->request.sequence, pipe);
1750 vblank->last_wait = vblwait->request.sequence;
1751 DRM_WAIT_ON(ret, vblank->queue, 3 * HZ,
1752 (((drm_vblank_count(dev, pipe) -
1753 vblwait->request.sequence) <= (1 << 23)) ||
1755 !dev->irq_enabled));
1757 if (ret != -EINTR) {
1760 vblwait->reply.sequence = drm_vblank_count_and_time(dev, pipe, &now);
1761 vblwait->reply.tval_sec = now.tv_sec;
1762 vblwait->reply.tval_usec = now.tv_usec;
1764 DRM_DEBUG_VBLANK("returning %d to client\n",
1765 vblwait->reply.sequence);
1767 DRM_DEBUG_VBLANK("vblank wait interrupted by signal\n");
1771 drm_vblank_put(dev, pipe);
1775 static void drm_handle_vblank_events(struct drm_device *dev, unsigned int pipe)
1777 struct drm_pending_vblank_event *e, *t;
1781 assert_spin_locked(&dev->event_lock);
1783 seq = drm_vblank_count_and_time(dev, pipe, &now);
1785 list_for_each_entry_safe(e, t, &dev->vblank_event_list, base.link) {
1786 if (e->pipe != pipe)
1788 if ((seq - e->event.sequence) > (1<<23))
1791 DRM_DEBUG_VBLANK("vblank event on %d, current %d\n",
1792 e->event.sequence, seq);
1794 list_del(&e->base.link);
1795 drm_vblank_put(dev, pipe);
1796 send_vblank_event(dev, e, seq, &now);
1799 trace_drm_vblank_event(pipe, seq);
1803 * drm_handle_vblank - handle a vblank event
1805 * @pipe: index of CRTC where this event occurred
1807 * Drivers should call this routine in their vblank interrupt handlers to
1808 * update the vblank counter and send any signals that may be pending.
1810 * This is the legacy version of drm_crtc_handle_vblank().
1812 bool drm_handle_vblank(struct drm_device *dev, unsigned int pipe)
1814 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
1815 unsigned long irqflags;
1817 if (WARN_ON_ONCE(!dev->num_crtcs))
1820 if (WARN_ON(pipe >= dev->num_crtcs))
1823 spin_lock_irqsave(&dev->event_lock, irqflags);
1825 /* Need timestamp lock to prevent concurrent execution with
1826 * vblank enable/disable, as this would cause inconsistent
1827 * or corrupted timestamps and vblank counts.
1829 lockmgr(&dev->vblank_time_lock, LK_EXCLUSIVE);
1831 /* Vblank irq handling disabled. Nothing to do. */
1832 if (!vblank->enabled) {
1833 lockmgr(&dev->vblank_time_lock, LK_RELEASE);
1834 spin_unlock_irqrestore(&dev->event_lock, irqflags);
1838 drm_update_vblank_count(dev, pipe, DRM_CALLED_FROM_VBLIRQ);
1840 lockmgr(&dev->vblank_time_lock, LK_RELEASE);
1842 wake_up(&vblank->queue);
1843 drm_handle_vblank_events(dev, pipe);
1845 spin_unlock_irqrestore(&dev->event_lock, irqflags);
1849 EXPORT_SYMBOL(drm_handle_vblank);
1852 * drm_crtc_handle_vblank - handle a vblank event
1853 * @crtc: where this event occurred
1855 * Drivers should call this routine in their vblank interrupt handlers to
1856 * update the vblank counter and send any signals that may be pending.
1858 * This is the native KMS version of drm_handle_vblank().
1861 * True if the event was successfully handled, false on failure.
1863 bool drm_crtc_handle_vblank(struct drm_crtc *crtc)
1865 return drm_handle_vblank(crtc->dev, drm_crtc_index(crtc));
1867 EXPORT_SYMBOL(drm_crtc_handle_vblank);
1870 * drm_vblank_no_hw_counter - "No hw counter" implementation of .get_vblank_counter()
1872 * @pipe: CRTC for which to read the counter
1874 * Drivers can plug this into the .get_vblank_counter() function if
1875 * there is no useable hardware frame counter available.
1880 u32 drm_vblank_no_hw_counter(struct drm_device *dev, unsigned int pipe)
1884 EXPORT_SYMBOL(drm_vblank_no_hw_counter);