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/interrupt.h> /* For task queue support */
40 #include <linux/slab.h>
42 #include <linux/vgaarb.h>
43 #include <linux/export.h>
45 /* Access macro for slots in vblank timestamp ringbuffer. */
46 #define vblanktimestamp(dev, pipe, count) \
47 ((dev)->vblank[pipe].time[(count) % DRM_VBLANKTIME_RBSIZE])
49 /* Retry timestamp calculation up to 3 times to satisfy
50 * drm_timestamp_precision before giving up.
52 #define DRM_TIMESTAMP_MAXRETRIES 3
54 /* Threshold in nanoseconds for detection of redundant
55 * vblank irq in drm_handle_vblank(). 1 msec should be ok.
57 #define DRM_REDUNDANT_VBLIRQ_THRESH_NS 1000000
60 drm_get_last_vbltimestamp(struct drm_device *dev, unsigned int pipe,
61 struct timeval *tvblank, unsigned flags);
63 static unsigned int drm_timestamp_precision = 20; /* Default to 20 usecs. */
66 * Default to use monotonic timestamps for wait-for-vblank and page-flip
69 unsigned int drm_timestamp_monotonic = 1;
71 static int drm_vblank_offdelay = 5000; /* Default to 5000 msecs. */
73 module_param_named(vblankoffdelay, drm_vblank_offdelay, int, 0600);
74 module_param_named(timestamp_precision_usec, drm_timestamp_precision, int, 0600);
75 module_param_named(timestamp_monotonic, drm_timestamp_monotonic, int, 0600);
77 static void store_vblank(struct drm_device *dev, unsigned int pipe,
79 struct timeval *t_vblank, u32 last)
81 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
84 assert_spin_locked(&dev->vblank_time_lock);
88 /* All writers hold the spinlock, but readers are serialized by
89 * the latching of vblank->count below.
91 tslot = vblank->count + vblank_count_inc;
92 vblanktimestamp(dev, pipe, tslot) = *t_vblank;
95 * vblank timestamp updates are protected on the write side with
96 * vblank_time_lock, but on the read side done locklessly using a
97 * sequence-lock on the vblank counter. Ensure correct ordering using
98 * memory barrriers. We need the barrier both before and also after the
99 * counter update to synchronize with the next timestamp write.
100 * The read-side barriers for this are in drm_vblank_count_and_time.
103 vblank->count += vblank_count_inc;
108 * drm_reset_vblank_timestamp - reset the last timestamp to the last vblank
110 * @pipe: index of CRTC for which to reset the timestamp
112 * Reset the stored timestamp for the current vblank count to correspond
113 * to the last vblank occurred.
115 * Only to be called from drm_vblank_on().
117 * Note: caller must hold dev->vbl_lock since this reads & writes
118 * device vblank fields.
120 static void drm_reset_vblank_timestamp(struct drm_device *dev, unsigned int pipe)
124 struct timeval t_vblank;
125 int count = DRM_TIMESTAMP_MAXRETRIES;
127 spin_lock(&dev->vblank_time_lock);
130 * sample the current counter to avoid random jumps
131 * when drm_vblank_enable() applies the diff
134 cur_vblank = dev->driver->get_vblank_counter(dev, pipe);
135 rc = drm_get_last_vbltimestamp(dev, pipe, &t_vblank, 0);
136 } while (cur_vblank != dev->driver->get_vblank_counter(dev, pipe) && --count > 0);
139 * Only reinitialize corresponding vblank timestamp if high-precision query
140 * available and didn't fail. Otherwise reinitialize delayed at next vblank
141 * interrupt and assign 0 for now, to mark the vblanktimestamp as invalid.
144 t_vblank = (struct timeval) {0, 0};
147 * +1 to make sure user will never see the same
148 * vblank counter value before and after a modeset
150 store_vblank(dev, pipe, 1, &t_vblank, cur_vblank);
152 spin_unlock(&dev->vblank_time_lock);
156 * drm_update_vblank_count - update the master vblank counter
158 * @pipe: counter to update
160 * Call back into the driver to update the appropriate vblank counter
161 * (specified by @pipe). Deal with wraparound, if it occurred, and
162 * update the last read value so we can deal with wraparound on the next
165 * Only necessary when going from off->on, to account for frames we
166 * didn't get an interrupt for.
168 * Note: caller must hold dev->vbl_lock since this reads & writes
169 * device vblank fields.
171 static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe,
174 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
175 u32 cur_vblank, diff;
177 struct timeval t_vblank;
178 int count = DRM_TIMESTAMP_MAXRETRIES;
179 int framedur_ns = vblank->framedur_ns;
182 * Interrupts were disabled prior to this call, so deal with counter
184 * NOTE! It's possible we lost a full dev->max_vblank_count + 1 events
185 * here if the register is small or we had vblank interrupts off for
188 * We repeat the hardware vblank counter & timestamp query until
189 * we get consistent results. This to prevent races between gpu
190 * updating its hardware counter while we are retrieving the
191 * corresponding vblank timestamp.
194 cur_vblank = dev->driver->get_vblank_counter(dev, pipe);
195 rc = drm_get_last_vbltimestamp(dev, pipe, &t_vblank, flags);
196 } while (cur_vblank != dev->driver->get_vblank_counter(dev, pipe) && --count > 0);
198 if (dev->max_vblank_count != 0) {
199 /* trust the hw counter when it's around */
200 diff = (cur_vblank - vblank->last) & dev->max_vblank_count;
201 } else if (rc && framedur_ns) {
202 const struct timeval *t_old;
205 t_old = &vblanktimestamp(dev, pipe, vblank->count);
206 diff_ns = timeval_to_ns(&t_vblank) - timeval_to_ns(t_old);
209 * Figure out how many vblanks we've missed based
210 * on the difference in the timestamps and the
211 * frame/field duration.
213 diff = DIV_ROUND_CLOSEST_ULL(diff_ns, framedur_ns);
215 if (diff == 0 && flags & DRM_CALLED_FROM_VBLIRQ)
216 DRM_DEBUG("crtc %u: Redundant vblirq ignored."
217 " diff_ns = %lld, framedur_ns = %d)\n",
218 pipe, (long long) diff_ns, framedur_ns);
220 /* some kind of default for drivers w/o accurate vbl timestamping */
221 diff = (flags & DRM_CALLED_FROM_VBLIRQ) != 0;
224 DRM_DEBUG("updating vblank count on crtc %u:"
225 " current=%u, diff=%u, hw=%u hw_last=%u\n",
226 pipe, vblank->count, diff, cur_vblank, vblank->last);
229 WARN_ON_ONCE(cur_vblank != vblank->last);
234 * Only reinitialize corresponding vblank timestamp if high-precision query
235 * available and didn't fail. Otherwise reinitialize delayed at next vblank
236 * interrupt and assign 0 for now, to mark the vblanktimestamp as invalid.
239 t_vblank = (struct timeval) {0, 0};
241 store_vblank(dev, pipe, diff, &t_vblank, cur_vblank);
245 * Disable vblank irq's on crtc, make sure that last vblank count
246 * of hardware and corresponding consistent software vblank counter
247 * are preserved, even if there are any spurious vblank irq's after
250 static void vblank_disable_and_save(struct drm_device *dev, unsigned int pipe)
252 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
253 unsigned long irqflags;
255 /* Prevent vblank irq processing while disabling vblank irqs,
256 * so no updates of timestamps or count can happen after we've
257 * disabled. Needed to prevent races in case of delayed irq's.
259 spin_lock_irqsave(&dev->vblank_time_lock, irqflags);
262 * Only disable vblank interrupts if they're enabled. This avoids
263 * calling the ->disable_vblank() operation in atomic context with the
264 * hardware potentially runtime suspended.
266 if (vblank->enabled) {
267 dev->driver->disable_vblank(dev, pipe);
268 vblank->enabled = false;
272 * Always update the count and timestamp to maintain the
273 * appearance that the counter has been ticking all along until
274 * this time. This makes the count account for the entire time
275 * between drm_vblank_on() and drm_vblank_off().
277 drm_update_vblank_count(dev, pipe, 0);
279 spin_unlock_irqrestore(&dev->vblank_time_lock, irqflags);
282 static void vblank_disable_fn(unsigned long arg)
284 struct drm_vblank_crtc *vblank = (void *)arg;
285 struct drm_device *dev = vblank->dev;
286 unsigned int pipe = vblank->pipe;
287 unsigned long irqflags;
289 if (!dev->vblank_disable_allowed)
292 spin_lock_irqsave(&dev->vbl_lock, irqflags);
293 if (atomic_read(&vblank->refcount) == 0 && vblank->enabled) {
294 DRM_DEBUG("disabling vblank on crtc %u\n", pipe);
295 vblank_disable_and_save(dev, pipe);
297 spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
301 * drm_vblank_cleanup - cleanup vblank support
304 * This function cleans up any resources allocated in drm_vblank_init.
306 void drm_vblank_cleanup(struct drm_device *dev)
310 /* Bail if the driver didn't call drm_vblank_init() */
311 if (dev->num_crtcs == 0)
314 for (pipe = 0; pipe < dev->num_crtcs; pipe++) {
315 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
317 WARN_ON(vblank->enabled &&
318 drm_core_check_feature(dev, DRIVER_MODESET));
320 del_timer_sync(&vblank->disable_timer);
327 EXPORT_SYMBOL(drm_vblank_cleanup);
330 * drm_vblank_init - initialize vblank support
332 * @num_crtcs: number of CRTCs supported by @dev
334 * This function initializes vblank support for @num_crtcs display pipelines.
337 * Zero on success or a negative error code on failure.
339 int drm_vblank_init(struct drm_device *dev, unsigned int num_crtcs)
344 spin_lock_init(&dev->vbl_lock);
345 spin_lock_init(&dev->vblank_time_lock);
347 dev->num_crtcs = num_crtcs;
349 dev->vblank = kcalloc(num_crtcs, sizeof(*dev->vblank), GFP_KERNEL);
353 for (i = 0; i < num_crtcs; i++) {
354 struct drm_vblank_crtc *vblank = &dev->vblank[i];
358 init_waitqueue_head(&vblank->queue);
359 setup_timer(&vblank->disable_timer, vblank_disable_fn,
360 (unsigned long)vblank);
363 DRM_INFO("Supports vblank timestamp caching Rev 2 (21.10.2013).\n");
365 /* Driver specific high-precision vblank timestamping supported? */
366 if (dev->driver->get_vblank_timestamp)
367 DRM_INFO("Driver supports precise vblank timestamp query.\n");
369 DRM_INFO("No driver support for vblank timestamp query.\n");
371 /* Must have precise timestamping for reliable vblank instant disable */
372 if (dev->vblank_disable_immediate && !dev->driver->get_vblank_timestamp) {
373 dev->vblank_disable_immediate = false;
374 DRM_INFO("Setting vblank_disable_immediate to false because "
375 "get_vblank_timestamp == NULL\n");
378 dev->vblank_disable_allowed = false;
386 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);
412 * drm_irq_install - install IRQ handler
414 * @irq: IRQ number to install the handler for
416 * Initializes the IRQ related data. Installs the handler, calling the driver
417 * irq_preinstall() and irq_postinstall() functions before and after the
420 * This is the simplified helper interface provided for drivers with no special
421 * needs. Drivers which need to install interrupt handlers for multiple
422 * interrupts must instead set drm_device->irq_enabled to signal the DRM core
423 * that vblank interrupts are available.
426 * Zero on success or a negative error code on failure.
428 int drm_irq_install(struct drm_device *dev, int irq)
431 unsigned long sh_flags = 0;
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 if (drm_core_check_feature(dev, DRIVER_IRQ_SHARED))
455 sh_flags = IRQF_SHARED;
457 ret = request_irq(irq, dev->driver->irq_handler,
458 sh_flags, dev->driver->name, dev);
461 dev->irq_enabled = false;
465 if (!drm_core_check_feature(dev, DRIVER_MODESET))
466 vga_client_register(dev->pdev, (void *)dev, drm_irq_vgaarb_nokms, NULL);
468 /* After installing handler */
469 if (dev->driver->irq_postinstall)
470 ret = dev->driver->irq_postinstall(dev);
473 dev->irq_enabled = false;
474 if (!drm_core_check_feature(dev, DRIVER_MODESET))
475 vga_client_register(dev->pdev, NULL, NULL, NULL);
483 EXPORT_SYMBOL(drm_irq_install);
486 * drm_irq_uninstall - uninstall the IRQ handler
489 * Calls the driver's irq_uninstall() function and unregisters the IRQ handler.
490 * This should only be called by drivers which used drm_irq_install() to set up
491 * their interrupt handler. Other drivers must only reset
492 * drm_device->irq_enabled to false.
494 * Note that for kernel modesetting drivers it is a bug if this function fails.
495 * The sanity checks are only to catch buggy user modesetting drivers which call
496 * the same function through an ioctl.
499 * Zero on success or a negative error code on failure.
501 int drm_irq_uninstall(struct drm_device *dev)
503 unsigned long irqflags;
507 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
510 irq_enabled = dev->irq_enabled;
511 dev->irq_enabled = false;
514 * Wake up any waiters so they don't hang. This is just to paper over
515 * isssues for UMS drivers which aren't in full control of their
516 * vblank/irq handling. KMS drivers must ensure that vblanks are all
517 * disabled when uninstalling the irq handler.
519 if (dev->num_crtcs) {
520 spin_lock_irqsave(&dev->vbl_lock, irqflags);
521 for (i = 0; i < dev->num_crtcs; i++) {
522 struct drm_vblank_crtc *vblank = &dev->vblank[i];
524 if (!vblank->enabled)
527 WARN_ON(drm_core_check_feature(dev, DRIVER_MODESET));
529 vblank_disable_and_save(dev, i);
530 wake_up(&vblank->queue);
532 spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
538 DRM_DEBUG("irq=%d\n", dev->irq);
540 if (!drm_core_check_feature(dev, DRIVER_MODESET))
541 vga_client_register(dev->pdev, NULL, NULL, NULL);
543 if (dev->driver->irq_uninstall)
544 dev->driver->irq_uninstall(dev);
546 free_irq(dev->irq, dev);
550 EXPORT_SYMBOL(drm_irq_uninstall);
555 * \param inode device inode.
556 * \param file_priv DRM file private.
557 * \param cmd command.
558 * \param arg user argument, pointing to a drm_control structure.
559 * \return zero on success or a negative number on failure.
561 * Calls irq_install() or irq_uninstall() according to \p arg.
563 int drm_control(struct drm_device *dev, void *data,
564 struct drm_file *file_priv)
566 struct drm_control *ctl = data;
569 /* if we haven't irq we fallback for compatibility reasons -
570 * this used to be a separate function in drm_dma.h
573 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
575 if (drm_core_check_feature(dev, DRIVER_MODESET))
577 /* UMS was only ever support on pci devices. */
578 if (WARN_ON(!dev->pdev))
582 case DRM_INST_HANDLER:
583 irq = dev->pdev->irq;
585 if (dev->if_version < DRM_IF_VERSION(1, 2) &&
588 mutex_lock(&dev->struct_mutex);
589 ret = drm_irq_install(dev, irq);
590 mutex_unlock(&dev->struct_mutex);
593 case DRM_UNINST_HANDLER:
594 mutex_lock(&dev->struct_mutex);
595 ret = drm_irq_uninstall(dev);
596 mutex_unlock(&dev->struct_mutex);
605 * drm_calc_timestamping_constants - calculate vblank timestamp constants
606 * @crtc: drm_crtc whose timestamp constants should be updated.
607 * @mode: display mode containing the scanout timings
609 * Calculate and store various constants which are later
610 * needed by vblank and swap-completion timestamping, e.g,
611 * by drm_calc_vbltimestamp_from_scanoutpos(). They are
612 * derived from CRTC's true scanout timing, so they take
613 * things like panel scaling or other adjustments into account.
615 void drm_calc_timestamping_constants(struct drm_crtc *crtc,
616 const struct drm_display_mode *mode)
618 struct drm_vblank_crtc *vblank = &crtc->dev->vblank[drm_crtc_index(crtc)];
619 int linedur_ns = 0, framedur_ns = 0;
620 int dotclock = mode->crtc_clock;
622 /* Valid dotclock? */
624 int frame_size = mode->crtc_htotal * mode->crtc_vtotal;
627 * Convert scanline length in pixels and video
628 * dot clock to line duration and frame duration
631 linedur_ns = div_u64((u64) mode->crtc_htotal * 1000000, dotclock);
632 framedur_ns = div_u64((u64) frame_size * 1000000, dotclock);
635 * Fields of interlaced scanout modes are only half a frame duration.
637 if (mode->flags & DRM_MODE_FLAG_INTERLACE)
640 DRM_ERROR("crtc %u: Can't calculate constants, dotclock = 0!\n",
643 vblank->linedur_ns = linedur_ns;
644 vblank->framedur_ns = framedur_ns;
646 DRM_DEBUG("crtc %u: hwmode: htotal %d, vtotal %d, vdisplay %d\n",
647 crtc->base.id, mode->crtc_htotal,
648 mode->crtc_vtotal, mode->crtc_vdisplay);
649 DRM_DEBUG("crtc %u: clock %d kHz framedur %d linedur %d\n",
650 crtc->base.id, dotclock, framedur_ns, linedur_ns);
652 EXPORT_SYMBOL(drm_calc_timestamping_constants);
655 * drm_calc_vbltimestamp_from_scanoutpos - precise vblank timestamp helper
657 * @pipe: index of CRTC whose vblank timestamp to retrieve
658 * @max_error: Desired maximum allowable error in timestamps (nanosecs)
659 * On return contains true maximum error of timestamp
660 * @vblank_time: Pointer to struct timeval which should receive the timestamp
661 * @flags: Flags to pass to driver:
663 * DRM_CALLED_FROM_VBLIRQ = If function is called from vbl IRQ handler
664 * @mode: mode which defines the scanout timings
666 * Implements calculation of exact vblank timestamps from given drm_display_mode
667 * timings and current video scanout position of a CRTC. This can be called from
668 * within get_vblank_timestamp() implementation of a kms driver to implement the
669 * actual timestamping.
671 * Should return timestamps conforming to the OML_sync_control OpenML
672 * extension specification. The timestamp corresponds to the end of
673 * the vblank interval, aka start of scanout of topmost-leftmost display
674 * pixel in the following video frame.
676 * Requires support for optional dev->driver->get_scanout_position()
677 * in kms driver, plus a bit of setup code to provide a drm_display_mode
678 * that corresponds to the true scanout timing.
680 * The current implementation only handles standard video modes. It
681 * returns as no operation if a doublescan or interlaced video mode is
682 * active. Higher level code is expected to handle this.
685 * Negative value on error, failure or if not supported in current
688 * -EINVAL - Invalid CRTC.
689 * -EAGAIN - Temporary unavailable, e.g., called before initial modeset.
690 * -ENOTSUPP - Function not supported in current display mode.
691 * -EIO - Failed, e.g., due to failed scanout position query.
693 * Returns or'ed positive status flags on success:
695 * DRM_VBLANKTIME_SCANOUTPOS_METHOD - Signal this method used for timestamping.
696 * DRM_VBLANKTIME_INVBL - Timestamp taken while scanout was in vblank interval.
699 int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
702 struct timeval *vblank_time,
704 const struct drm_display_mode *mode)
706 struct timeval tv_etime;
707 ktime_t stime, etime;
708 unsigned int vbl_status;
709 int ret = DRM_VBLANKTIME_SCANOUTPOS_METHOD;
711 int delta_ns, duration_ns;
713 if (pipe >= dev->num_crtcs) {
714 DRM_ERROR("Invalid crtc %u\n", pipe);
718 /* Scanout position query not supported? Should not happen. */
719 if (!dev->driver->get_scanout_position) {
720 DRM_ERROR("Called from driver w/o get_scanout_position()!?\n");
724 /* If mode timing undefined, just return as no-op:
725 * Happens during initial modesetting of a crtc.
727 if (mode->crtc_clock == 0) {
728 DRM_DEBUG("crtc %u: Noop due to uninitialized mode.\n", pipe);
732 /* Get current scanout position with system timestamp.
733 * Repeat query up to DRM_TIMESTAMP_MAXRETRIES times
734 * if single query takes longer than max_error nanoseconds.
736 * This guarantees a tight bound on maximum error if
737 * code gets preempted or delayed for some reason.
739 for (i = 0; i < DRM_TIMESTAMP_MAXRETRIES; i++) {
741 * Get vertical and horizontal scanout position vpos, hpos,
742 * and bounding timestamps stime, etime, pre/post query.
744 vbl_status = dev->driver->get_scanout_position(dev, pipe, flags,
749 /* Return as no-op if scanout query unsupported or failed. */
750 if (!(vbl_status & DRM_SCANOUTPOS_VALID)) {
751 DRM_DEBUG("crtc %u : scanoutpos query failed [0x%x].\n",
756 /* Compute uncertainty in timestamp of scanout position query. */
757 duration_ns = ktime_to_ns(etime) - ktime_to_ns(stime);
759 /* Accept result with < max_error nsecs timing uncertainty. */
760 if (duration_ns <= *max_error)
764 /* Noisy system timing? */
765 if (i == DRM_TIMESTAMP_MAXRETRIES) {
766 DRM_DEBUG("crtc %u: Noisy timestamp %d us > %d us [%d reps].\n",
767 pipe, duration_ns/1000, *max_error/1000, i);
770 /* Return upper bound of timestamp precision error. */
771 *max_error = duration_ns;
773 /* Check if in vblank area:
774 * vpos is >=0 in video scanout area, but negative
775 * within vblank area, counting down the number of lines until
778 if (vbl_status & DRM_SCANOUTPOS_IN_VBLANK)
779 ret |= DRM_VBLANKTIME_IN_VBLANK;
781 /* Convert scanout position into elapsed time at raw_time query
782 * since start of scanout at first display scanline. delta_ns
783 * can be negative if start of scanout hasn't happened yet.
785 delta_ns = div_s64(1000000LL * (vpos * mode->crtc_htotal + hpos),
788 if (!drm_timestamp_monotonic)
789 etime = ktime_mono_to_real(etime);
791 /* save this only for debugging purposes */
792 tv_etime = ktime_to_timeval(etime);
793 /* Subtract time delta from raw timestamp to get final
794 * vblank_time timestamp for end of vblank.
797 etime = ktime_add_ns(etime, -delta_ns);
799 etime = ktime_sub_ns(etime, delta_ns);
800 *vblank_time = ktime_to_timeval(etime);
802 DRM_DEBUG("crtc %u : v 0x%x p(%d,%d)@ %ld.%ld -> %ld.%ld [e %d us, %d rep]\n",
803 pipe, vbl_status, hpos, vpos,
804 (long)tv_etime.tv_sec, (long)tv_etime.tv_usec,
805 (long)vblank_time->tv_sec, (long)vblank_time->tv_usec,
806 duration_ns/1000, i);
810 EXPORT_SYMBOL(drm_calc_vbltimestamp_from_scanoutpos);
812 static struct timeval get_drm_timestamp(void)
816 now = drm_timestamp_monotonic ? ktime_get() : ktime_get_real();
817 return ktime_to_timeval(now);
821 * drm_get_last_vbltimestamp - retrieve raw timestamp for the most recent
824 * @pipe: index of CRTC whose vblank timestamp to retrieve
825 * @tvblank: Pointer to target struct timeval which should receive the timestamp
826 * @flags: Flags to pass to driver:
828 * DRM_CALLED_FROM_VBLIRQ = If function is called from vbl IRQ handler
830 * Fetches the system timestamp corresponding to the time of the most recent
831 * vblank interval on specified CRTC. May call into kms-driver to
832 * compute the timestamp with a high-precision GPU specific method.
834 * Returns zero if timestamp originates from uncorrected do_gettimeofday()
835 * call, i.e., it isn't very precisely locked to the true vblank.
838 * True if timestamp is considered to be very precise, false otherwise.
841 drm_get_last_vbltimestamp(struct drm_device *dev, unsigned int pipe,
842 struct timeval *tvblank, unsigned flags)
846 /* Define requested maximum error on timestamps (nanoseconds). */
847 int max_error = (int) drm_timestamp_precision * 1000;
849 /* Query driver if possible and precision timestamping enabled. */
850 if (dev->driver->get_vblank_timestamp && (max_error > 0)) {
851 ret = dev->driver->get_vblank_timestamp(dev, pipe, &max_error,
857 /* GPU high precision timestamp query unsupported or failed.
858 * Return current monotonic/gettimeofday timestamp as best estimate.
860 *tvblank = get_drm_timestamp();
866 * drm_vblank_count - retrieve "cooked" vblank counter value
868 * @pipe: index of CRTC for which to retrieve the counter
870 * Fetches the "cooked" vblank count value that represents the number of
871 * vblank events since the system was booted, including lost events due to
872 * modesetting activity.
874 * This is the legacy version of drm_crtc_vblank_count().
877 * The software vblank counter.
879 u32 drm_vblank_count(struct drm_device *dev, int pipe)
881 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
883 if (WARN_ON(pipe >= dev->num_crtcs))
886 return vblank->count;
888 EXPORT_SYMBOL(drm_vblank_count);
891 * drm_crtc_vblank_count - retrieve "cooked" vblank counter value
892 * @crtc: which counter to retrieve
894 * Fetches the "cooked" vblank count value that represents the number of
895 * vblank events since the system was booted, including lost events due to
896 * modesetting activity.
898 * This is the native KMS version of drm_vblank_count().
901 * The software vblank counter.
903 u32 drm_crtc_vblank_count(struct drm_crtc *crtc)
905 return drm_vblank_count(crtc->dev, drm_crtc_index(crtc));
907 EXPORT_SYMBOL(drm_crtc_vblank_count);
910 * drm_vblank_count_and_time - retrieve "cooked" vblank counter value and the
911 * system timestamp corresponding to that vblank counter value.
913 * @pipe: index of CRTC whose counter to retrieve
914 * @vblanktime: Pointer to struct timeval to receive the vblank timestamp.
916 * Fetches the "cooked" vblank count value that represents the number of
917 * vblank events since the system was booted, including lost events due to
918 * modesetting activity. Returns corresponding system timestamp of the time
919 * of the vblank interval that corresponds to the current vblank counter value.
921 u32 drm_vblank_count_and_time(struct drm_device *dev, unsigned int pipe,
922 struct timeval *vblanktime)
924 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
925 int count = DRM_TIMESTAMP_MAXRETRIES;
928 if (WARN_ON(pipe >= dev->num_crtcs))
932 * Vblank timestamps are read lockless. To ensure consistency the vblank
933 * counter is rechecked and ordering is ensured using memory barriers.
934 * This works like a seqlock. The write-side barriers are in store_vblank.
937 cur_vblank = vblank->count;
939 *vblanktime = vblanktimestamp(dev, pipe, cur_vblank);
941 } while (cur_vblank != vblank->count && --count > 0);
945 EXPORT_SYMBOL(drm_vblank_count_and_time);
947 static void send_vblank_event(struct drm_device *dev,
948 struct drm_pending_vblank_event *e,
949 unsigned long seq, struct timeval *now)
951 WARN_ON_SMP(!spin_is_locked(&dev->event_lock));
952 e->event.sequence = seq;
953 e->event.tv_sec = now->tv_sec;
954 e->event.tv_usec = now->tv_usec;
956 list_add_tail(&e->base.link,
957 &e->base.file_priv->event_list);
958 wake_up_interruptible(&e->base.file_priv->event_wait);
959 trace_drm_vblank_event_delivered(e->base.pid, e->pipe,
964 * drm_send_vblank_event - helper to send vblank event after pageflip
967 * @e: the event to send
969 * Updates sequence # and timestamp on event, and sends it to userspace.
970 * Caller must hold event lock.
972 * This is the legacy version of drm_crtc_send_vblank_event().
974 void drm_send_vblank_event(struct drm_device *dev, unsigned int pipe,
975 struct drm_pending_vblank_event *e)
980 if (dev->num_crtcs > 0) {
981 seq = drm_vblank_count_and_time(dev, pipe, &now);
985 now = get_drm_timestamp();
988 send_vblank_event(dev, e, seq, &now);
990 EXPORT_SYMBOL(drm_send_vblank_event);
993 * drm_crtc_send_vblank_event - helper to send vblank event after pageflip
994 * @crtc: the source CRTC of the vblank event
995 * @e: the event to send
997 * Updates sequence # and timestamp on event, and sends it to userspace.
998 * Caller must hold event lock.
1000 * This is the native KMS version of drm_send_vblank_event().
1002 void drm_crtc_send_vblank_event(struct drm_crtc *crtc,
1003 struct drm_pending_vblank_event *e)
1005 drm_send_vblank_event(crtc->dev, drm_crtc_index(crtc), e);
1007 EXPORT_SYMBOL(drm_crtc_send_vblank_event);
1010 * drm_vblank_enable - enable the vblank interrupt on a CRTC
1015 * Zero on success or a negative error code on failure.
1017 static int drm_vblank_enable(struct drm_device *dev, unsigned int pipe)
1019 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
1022 assert_spin_locked(&dev->vbl_lock);
1024 spin_lock(&dev->vblank_time_lock);
1026 if (!vblank->enabled) {
1028 * Enable vblank irqs under vblank_time_lock protection.
1029 * All vblank count & timestamp updates are held off
1030 * until we are done reinitializing master counter and
1031 * timestamps. Filtercode in drm_handle_vblank() will
1032 * prevent double-accounting of same vblank interval.
1034 ret = dev->driver->enable_vblank(dev, pipe);
1035 DRM_DEBUG("enabling vblank on crtc %u, ret: %d\n", pipe, ret);
1037 atomic_dec(&vblank->refcount);
1039 vblank->enabled = true;
1040 drm_update_vblank_count(dev, pipe, 0);
1044 spin_unlock(&dev->vblank_time_lock);
1050 * drm_vblank_get - get a reference count on vblank events
1052 * @pipe: index of CRTC to own
1054 * Acquire a reference count on vblank events to avoid having them disabled
1057 * This is the legacy version of drm_crtc_vblank_get().
1060 * Zero on success or a negative error code on failure.
1062 int drm_vblank_get(struct drm_device *dev, unsigned int pipe)
1064 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
1065 unsigned long irqflags;
1068 if (!dev->num_crtcs)
1071 if (WARN_ON(pipe >= dev->num_crtcs))
1074 spin_lock_irqsave(&dev->vbl_lock, irqflags);
1075 /* Going from 0->1 means we have to enable interrupts again */
1076 if (atomic_add_return(1, &vblank->refcount) == 1) {
1077 ret = drm_vblank_enable(dev, pipe);
1079 if (!vblank->enabled) {
1080 atomic_dec(&vblank->refcount);
1084 spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
1088 EXPORT_SYMBOL(drm_vblank_get);
1091 * drm_crtc_vblank_get - get a reference count on vblank events
1092 * @crtc: which CRTC to own
1094 * Acquire a reference count on vblank events to avoid having them disabled
1097 * This is the native kms version of drm_vblank_get().
1100 * Zero on success or a negative error code on failure.
1102 int drm_crtc_vblank_get(struct drm_crtc *crtc)
1104 return drm_vblank_get(crtc->dev, drm_crtc_index(crtc));
1106 EXPORT_SYMBOL(drm_crtc_vblank_get);
1109 * drm_vblank_put - release ownership of vblank events
1111 * @pipe: index of CRTC to release
1113 * Release ownership of a given vblank counter, turning off interrupts
1114 * if possible. Disable interrupts after drm_vblank_offdelay milliseconds.
1116 * This is the legacy version of drm_crtc_vblank_put().
1118 void drm_vblank_put(struct drm_device *dev, unsigned int pipe)
1120 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
1122 if (WARN_ON(pipe >= dev->num_crtcs))
1125 if (WARN_ON(atomic_read(&vblank->refcount) == 0))
1128 /* Last user schedules interrupt disable */
1129 if (atomic_dec_and_test(&vblank->refcount)) {
1130 if (drm_vblank_offdelay == 0)
1132 else if (dev->vblank_disable_immediate || drm_vblank_offdelay < 0)
1133 vblank_disable_fn((unsigned long)vblank);
1135 mod_timer(&vblank->disable_timer,
1136 jiffies + ((drm_vblank_offdelay * HZ)/1000));
1139 EXPORT_SYMBOL(drm_vblank_put);
1142 * drm_crtc_vblank_put - give up ownership of vblank events
1143 * @crtc: which counter to give up
1145 * Release ownership of a given vblank counter, turning off interrupts
1146 * if possible. Disable interrupts after drm_vblank_offdelay milliseconds.
1148 * This is the native kms version of drm_vblank_put().
1150 void drm_crtc_vblank_put(struct drm_crtc *crtc)
1152 drm_vblank_put(crtc->dev, drm_crtc_index(crtc));
1154 EXPORT_SYMBOL(drm_crtc_vblank_put);
1157 * drm_wait_one_vblank - wait for one vblank
1161 * This waits for one vblank to pass on @pipe, using the irq driver interfaces.
1162 * It is a failure to call this when the vblank irq for @pipe is disabled, e.g.
1163 * due to lack of driver support or because the crtc is off.
1165 void drm_wait_one_vblank(struct drm_device *dev, unsigned int pipe)
1167 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
1171 if (WARN_ON(pipe >= dev->num_crtcs))
1174 ret = drm_vblank_get(dev, pipe);
1175 if (WARN(ret, "vblank not available on crtc %i, ret=%i\n", pipe, ret))
1178 last = drm_vblank_count(dev, pipe);
1180 ret = wait_event_timeout(vblank->queue,
1181 last != drm_vblank_count(dev, pipe),
1182 msecs_to_jiffies(100));
1184 WARN(ret == 0, "vblank wait timed out on crtc %i\n", pipe);
1186 drm_vblank_put(dev, pipe);
1188 EXPORT_SYMBOL(drm_wait_one_vblank);
1191 * drm_crtc_wait_one_vblank - wait for one vblank
1194 * This waits for one vblank to pass on @crtc, using the irq driver interfaces.
1195 * It is a failure to call this when the vblank irq for @crtc is disabled, e.g.
1196 * due to lack of driver support or because the crtc is off.
1198 void drm_crtc_wait_one_vblank(struct drm_crtc *crtc)
1200 drm_wait_one_vblank(crtc->dev, drm_crtc_index(crtc));
1202 EXPORT_SYMBOL(drm_crtc_wait_one_vblank);
1205 * drm_vblank_off - disable vblank events on a CRTC
1209 * Drivers can use this function to shut down the vblank interrupt handling when
1210 * disabling a crtc. This function ensures that the latest vblank frame count is
1211 * stored so that drm_vblank_on() can restore it again.
1213 * Drivers must use this function when the hardware vblank counter can get
1214 * reset, e.g. when suspending.
1216 * This is the legacy version of drm_crtc_vblank_off().
1218 void drm_vblank_off(struct drm_device *dev, unsigned int pipe)
1220 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
1221 struct drm_pending_vblank_event *e, *t;
1223 unsigned long irqflags;
1226 if (WARN_ON(pipe >= dev->num_crtcs))
1229 spin_lock_irqsave(&dev->event_lock, irqflags);
1231 spin_lock(&dev->vbl_lock);
1232 vblank_disable_and_save(dev, pipe);
1233 wake_up(&vblank->queue);
1236 * Prevent subsequent drm_vblank_get() from re-enabling
1237 * the vblank interrupt by bumping the refcount.
1239 if (!vblank->inmodeset) {
1240 atomic_inc(&vblank->refcount);
1241 vblank->inmodeset = 1;
1243 spin_unlock(&dev->vbl_lock);
1245 /* Send any queued vblank events, lest the natives grow disquiet */
1246 seq = drm_vblank_count_and_time(dev, pipe, &now);
1248 list_for_each_entry_safe(e, t, &dev->vblank_event_list, base.link) {
1249 if (e->pipe != pipe)
1251 DRM_DEBUG("Sending premature vblank event on disable: \
1252 wanted %d, current %d\n",
1253 e->event.sequence, seq);
1254 list_del(&e->base.link);
1255 drm_vblank_put(dev, pipe);
1256 send_vblank_event(dev, e, seq, &now);
1258 spin_unlock_irqrestore(&dev->event_lock, irqflags);
1260 EXPORT_SYMBOL(drm_vblank_off);
1263 * drm_crtc_vblank_off - disable vblank events on a CRTC
1264 * @crtc: CRTC in question
1266 * Drivers can use this function to shut down the vblank interrupt handling when
1267 * disabling a crtc. This function ensures that the latest vblank frame count is
1268 * stored so that drm_vblank_on can restore it again.
1270 * Drivers must use this function when the hardware vblank counter can get
1271 * reset, e.g. when suspending.
1273 * This is the native kms version of drm_vblank_off().
1275 void drm_crtc_vblank_off(struct drm_crtc *crtc)
1277 drm_vblank_off(crtc->dev, drm_crtc_index(crtc));
1279 EXPORT_SYMBOL(drm_crtc_vblank_off);
1282 * drm_crtc_vblank_reset - reset vblank state to off on a CRTC
1283 * @crtc: CRTC in question
1285 * Drivers can use this function to reset the vblank state to off at load time.
1286 * Drivers should use this together with the drm_crtc_vblank_off() and
1287 * drm_crtc_vblank_on() functions. The difference compared to
1288 * drm_crtc_vblank_off() is that this function doesn't save the vblank counter
1289 * and hence doesn't need to call any driver hooks.
1291 void drm_crtc_vblank_reset(struct drm_crtc *crtc)
1293 struct drm_device *dev = crtc->dev;
1294 unsigned long irqflags;
1295 unsigned int pipe = drm_crtc_index(crtc);
1296 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
1298 spin_lock_irqsave(&dev->vbl_lock, irqflags);
1300 * Prevent subsequent drm_vblank_get() from enabling the vblank
1301 * interrupt by bumping the refcount.
1303 if (!vblank->inmodeset) {
1304 atomic_inc(&vblank->refcount);
1305 vblank->inmodeset = 1;
1307 spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
1309 WARN_ON(!list_empty(&dev->vblank_event_list));
1311 EXPORT_SYMBOL(drm_crtc_vblank_reset);
1314 * drm_vblank_on - enable vblank events on a CRTC
1318 * This functions restores the vblank interrupt state captured with
1319 * drm_vblank_off() again. Note that calls to drm_vblank_on() and
1320 * drm_vblank_off() can be unbalanced and so can also be unconditionally called
1321 * in driver load code to reflect the current hardware state of the crtc.
1323 * This is the legacy version of drm_crtc_vblank_on().
1325 void drm_vblank_on(struct drm_device *dev, unsigned int pipe)
1327 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
1328 unsigned long irqflags;
1330 if (WARN_ON(pipe >= dev->num_crtcs))
1333 spin_lock_irqsave(&dev->vbl_lock, irqflags);
1334 /* Drop our private "prevent drm_vblank_get" refcount */
1335 if (vblank->inmodeset) {
1336 atomic_dec(&vblank->refcount);
1337 vblank->inmodeset = 0;
1340 drm_reset_vblank_timestamp(dev, pipe);
1343 * re-enable interrupts if there are users left, or the
1344 * user wishes vblank interrupts to be enabled all the time.
1346 if (atomic_read(&vblank->refcount) != 0 ||
1347 (!dev->vblank_disable_immediate && drm_vblank_offdelay == 0))
1348 WARN_ON(drm_vblank_enable(dev, pipe));
1349 spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
1351 EXPORT_SYMBOL(drm_vblank_on);
1354 * drm_crtc_vblank_on - enable vblank events on a CRTC
1355 * @crtc: CRTC in question
1357 * This functions restores the vblank interrupt state captured with
1358 * drm_vblank_off() again. Note that calls to drm_vblank_on() and
1359 * drm_vblank_off() can be unbalanced and so can also be unconditionally called
1360 * in driver load code to reflect the current hardware state of the crtc.
1362 * This is the native kms version of drm_vblank_on().
1364 void drm_crtc_vblank_on(struct drm_crtc *crtc)
1366 drm_vblank_on(crtc->dev, drm_crtc_index(crtc));
1368 EXPORT_SYMBOL(drm_crtc_vblank_on);
1371 * drm_vblank_pre_modeset - account for vblanks across mode sets
1375 * Account for vblank events across mode setting events, which will likely
1376 * reset the hardware frame counter.
1378 * This is done by grabbing a temporary vblank reference to ensure that the
1379 * vblank interrupt keeps running across the modeset sequence. With this the
1380 * software-side vblank frame counting will ensure that there are no jumps or
1383 * Unfortunately this approach is racy and also doesn't work when the vblank
1384 * interrupt stops running, e.g. across system suspend resume. It is therefore
1385 * highly recommended that drivers use the newer drm_vblank_off() and
1386 * drm_vblank_on() instead. drm_vblank_pre_modeset() only works correctly when
1387 * using "cooked" software vblank frame counters and not relying on any hardware
1390 * Drivers must call drm_vblank_post_modeset() when re-enabling the same crtc
1393 void drm_vblank_pre_modeset(struct drm_device *dev, unsigned int pipe)
1395 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
1397 /* vblank is not initialized (IRQ not installed ?), or has been freed */
1398 if (!dev->num_crtcs)
1401 if (WARN_ON(pipe >= dev->num_crtcs))
1405 * To avoid all the problems that might happen if interrupts
1406 * were enabled/disabled around or between these calls, we just
1407 * have the kernel take a reference on the CRTC (just once though
1408 * to avoid corrupting the count if multiple, mismatch calls occur),
1409 * so that interrupts remain enabled in the interim.
1411 if (!vblank->inmodeset) {
1412 vblank->inmodeset = 0x1;
1413 if (drm_vblank_get(dev, pipe) == 0)
1414 vblank->inmodeset |= 0x2;
1417 EXPORT_SYMBOL(drm_vblank_pre_modeset);
1420 * drm_vblank_post_modeset - undo drm_vblank_pre_modeset changes
1424 * This function again drops the temporary vblank reference acquired in
1425 * drm_vblank_pre_modeset.
1427 void drm_vblank_post_modeset(struct drm_device *dev, unsigned int pipe)
1429 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
1430 unsigned long irqflags;
1432 /* vblank is not initialized (IRQ not installed ?), or has been freed */
1433 if (!dev->num_crtcs)
1436 if (WARN_ON(pipe >= dev->num_crtcs))
1439 if (vblank->inmodeset) {
1440 spin_lock_irqsave(&dev->vbl_lock, irqflags);
1441 dev->vblank_disable_allowed = true;
1442 spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
1444 if (vblank->inmodeset & 0x2)
1445 drm_vblank_put(dev, pipe);
1447 vblank->inmodeset = 0;
1450 EXPORT_SYMBOL(drm_vblank_post_modeset);
1453 * drm_modeset_ctl - handle vblank event counter changes across mode switch
1454 * @DRM_IOCTL_ARGS: standard ioctl arguments
1456 * Applications should call the %_DRM_PRE_MODESET and %_DRM_POST_MODESET
1457 * ioctls around modesetting so that any lost vblank events are accounted for.
1459 * Generally the counter will reset across mode sets. If interrupts are
1460 * enabled around this call, we don't have to do anything since the counter
1461 * will have already been incremented.
1463 int drm_modeset_ctl(struct drm_device *dev, void *data,
1464 struct drm_file *file_priv)
1466 struct drm_modeset_ctl *modeset = data;
1469 /* If drm_vblank_init() hasn't been called yet, just no-op */
1470 if (!dev->num_crtcs)
1473 /* KMS drivers handle this internally */
1474 if (drm_core_check_feature(dev, DRIVER_MODESET))
1477 pipe = modeset->crtc;
1478 if (pipe >= dev->num_crtcs)
1481 switch (modeset->cmd) {
1482 case _DRM_PRE_MODESET:
1483 drm_vblank_pre_modeset(dev, pipe);
1485 case _DRM_POST_MODESET:
1486 drm_vblank_post_modeset(dev, pipe);
1495 static int drm_queue_vblank_event(struct drm_device *dev, unsigned int pipe,
1496 union drm_wait_vblank *vblwait,
1497 struct drm_file *file_priv)
1499 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
1500 struct drm_pending_vblank_event *e;
1502 unsigned long flags;
1506 e = kzalloc(sizeof(*e), GFP_KERNEL);
1513 e->base.pid = current->pid;
1514 e->event.base.type = DRM_EVENT_VBLANK;
1515 e->event.base.length = sizeof(e->event);
1516 e->event.user_data = vblwait->request.signal;
1517 e->base.event = &e->event.base;
1518 e->base.file_priv = file_priv;
1519 e->base.destroy = (void (*) (struct drm_pending_event *)) kfree;
1521 spin_lock_irqsave(&dev->event_lock, flags);
1524 * drm_vblank_off() might have been called after we called
1525 * drm_vblank_get(). drm_vblank_off() holds event_lock
1526 * around the vblank disable, so no need for further locking.
1527 * The reference from drm_vblank_get() protects against
1528 * vblank disable from another source.
1530 if (!vblank->enabled) {
1535 if (file_priv->event_space < sizeof(e->event)) {
1540 file_priv->event_space -= sizeof(e->event);
1541 seq = drm_vblank_count_and_time(dev, pipe, &now);
1543 if ((vblwait->request.type & _DRM_VBLANK_NEXTONMISS) &&
1544 (seq - vblwait->request.sequence) <= (1 << 23)) {
1545 vblwait->request.sequence = seq + 1;
1546 vblwait->reply.sequence = vblwait->request.sequence;
1549 DRM_DEBUG("event on vblank count %d, current %d, crtc %u\n",
1550 vblwait->request.sequence, seq, pipe);
1552 trace_drm_vblank_event_queued(current->pid, pipe,
1553 vblwait->request.sequence);
1555 e->event.sequence = vblwait->request.sequence;
1556 if ((seq - vblwait->request.sequence) <= (1 << 23)) {
1557 drm_vblank_put(dev, pipe);
1558 send_vblank_event(dev, e, seq, &now);
1559 vblwait->reply.sequence = seq;
1561 /* drm_handle_vblank_events will call drm_vblank_put */
1562 list_add_tail(&e->base.link, &dev->vblank_event_list);
1563 vblwait->reply.sequence = vblwait->request.sequence;
1566 spin_unlock_irqrestore(&dev->event_lock, flags);
1571 spin_unlock_irqrestore(&dev->event_lock, flags);
1574 drm_vblank_put(dev, pipe);
1581 * \param inode device inode.
1582 * \param file_priv DRM file private.
1583 * \param cmd command.
1584 * \param data user argument, pointing to a drm_wait_vblank structure.
1585 * \return zero on success or a negative number on failure.
1587 * This function enables the vblank interrupt on the pipe requested, then
1588 * sleeps waiting for the requested sequence number to occur, and drops
1589 * the vblank interrupt refcount afterwards. (vblank IRQ disable follows that
1590 * after a timeout with no further vblank waits scheduled).
1592 int drm_wait_vblank(struct drm_device *dev, void *data,
1593 struct drm_file *file_priv)
1595 struct drm_vblank_crtc *vblank;
1596 union drm_wait_vblank *vblwait = data;
1598 unsigned int flags, seq, pipe, high_pipe;
1600 if (!dev->irq_enabled)
1603 if (vblwait->request.type & _DRM_VBLANK_SIGNAL)
1606 if (vblwait->request.type &
1607 ~(_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK |
1608 _DRM_VBLANK_HIGH_CRTC_MASK)) {
1609 DRM_ERROR("Unsupported type value 0x%x, supported mask 0x%x\n",
1610 vblwait->request.type,
1611 (_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK |
1612 _DRM_VBLANK_HIGH_CRTC_MASK));
1616 flags = vblwait->request.type & _DRM_VBLANK_FLAGS_MASK;
1617 high_pipe = (vblwait->request.type & _DRM_VBLANK_HIGH_CRTC_MASK);
1619 pipe = high_pipe >> _DRM_VBLANK_HIGH_CRTC_SHIFT;
1621 pipe = flags & _DRM_VBLANK_SECONDARY ? 1 : 0;
1622 if (pipe >= dev->num_crtcs)
1625 vblank = &dev->vblank[pipe];
1627 ret = drm_vblank_get(dev, pipe);
1629 DRM_DEBUG("failed to acquire vblank counter, %d\n", ret);
1632 seq = drm_vblank_count(dev, pipe);
1634 switch (vblwait->request.type & _DRM_VBLANK_TYPES_MASK) {
1635 case _DRM_VBLANK_RELATIVE:
1636 vblwait->request.sequence += seq;
1637 vblwait->request.type &= ~_DRM_VBLANK_RELATIVE;
1638 case _DRM_VBLANK_ABSOLUTE:
1645 if (flags & _DRM_VBLANK_EVENT) {
1646 /* must hold on to the vblank ref until the event fires
1647 * drm_vblank_put will be called asynchronously
1649 return drm_queue_vblank_event(dev, pipe, vblwait, file_priv);
1652 if ((flags & _DRM_VBLANK_NEXTONMISS) &&
1653 (seq - vblwait->request.sequence) <= (1<<23)) {
1654 vblwait->request.sequence = seq + 1;
1657 DRM_DEBUG("waiting on vblank count %d, crtc %u\n",
1658 vblwait->request.sequence, pipe);
1659 vblank->last_wait = vblwait->request.sequence;
1660 DRM_WAIT_ON(ret, vblank->queue, 3 * HZ,
1661 (((drm_vblank_count(dev, pipe) -
1662 vblwait->request.sequence) <= (1 << 23)) ||
1664 !dev->irq_enabled));
1666 if (ret != -EINTR) {
1669 vblwait->reply.sequence = drm_vblank_count_and_time(dev, pipe, &now);
1670 vblwait->reply.tval_sec = now.tv_sec;
1671 vblwait->reply.tval_usec = now.tv_usec;
1673 DRM_DEBUG("returning %d to client\n",
1674 vblwait->reply.sequence);
1676 DRM_DEBUG("vblank wait interrupted by signal\n");
1680 drm_vblank_put(dev, pipe);
1684 static void drm_handle_vblank_events(struct drm_device *dev, unsigned int pipe)
1686 struct drm_pending_vblank_event *e, *t;
1690 assert_spin_locked(&dev->event_lock);
1692 seq = drm_vblank_count_and_time(dev, pipe, &now);
1694 list_for_each_entry_safe(e, t, &dev->vblank_event_list, base.link) {
1695 if (e->pipe != pipe)
1697 if ((seq - e->event.sequence) > (1<<23))
1700 DRM_DEBUG("vblank event on %d, current %d\n",
1701 e->event.sequence, seq);
1703 list_del(&e->base.link);
1704 drm_vblank_put(dev, pipe);
1705 send_vblank_event(dev, e, seq, &now);
1708 trace_drm_vblank_event(pipe, seq);
1712 * drm_handle_vblank - handle a vblank event
1714 * @pipe: index of CRTC where this event occurred
1716 * Drivers should call this routine in their vblank interrupt handlers to
1717 * update the vblank counter and send any signals that may be pending.
1719 * This is the legacy version of drm_crtc_handle_vblank().
1721 bool drm_handle_vblank(struct drm_device *dev, unsigned int pipe)
1723 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
1724 unsigned long irqflags;
1726 if (WARN_ON_ONCE(!dev->num_crtcs))
1729 if (WARN_ON(pipe >= dev->num_crtcs))
1732 spin_lock_irqsave(&dev->event_lock, irqflags);
1734 /* Need timestamp lock to prevent concurrent execution with
1735 * vblank enable/disable, as this would cause inconsistent
1736 * or corrupted timestamps and vblank counts.
1738 spin_lock(&dev->vblank_time_lock);
1740 /* Vblank irq handling disabled. Nothing to do. */
1741 if (!vblank->enabled) {
1742 spin_unlock(&dev->vblank_time_lock);
1743 spin_unlock_irqrestore(&dev->event_lock, irqflags);
1747 drm_update_vblank_count(dev, pipe, DRM_CALLED_FROM_VBLIRQ);
1749 spin_unlock(&dev->vblank_time_lock);
1751 wake_up(&vblank->queue);
1752 drm_handle_vblank_events(dev, pipe);
1754 spin_unlock_irqrestore(&dev->event_lock, irqflags);
1758 EXPORT_SYMBOL(drm_handle_vblank);
1761 * drm_crtc_handle_vblank - handle a vblank event
1762 * @crtc: where this event occurred
1764 * Drivers should call this routine in their vblank interrupt handlers to
1765 * update the vblank counter and send any signals that may be pending.
1767 * This is the native KMS version of drm_handle_vblank().
1770 * True if the event was successfully handled, false on failure.
1772 bool drm_crtc_handle_vblank(struct drm_crtc *crtc)
1774 return drm_handle_vblank(crtc->dev, drm_crtc_index(crtc));
1776 EXPORT_SYMBOL(drm_crtc_handle_vblank);