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, crtc, count) \
47 ((dev)->vblank[crtc].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
, int crtc
,
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
, int crtc
,
78 unsigned vblank_count_inc
,
79 struct timeval
*t_vblank
)
81 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[crtc
];
84 assert_spin_locked(&dev
->vblank_time_lock
);
87 /* All writers hold the spinlock, but readers are serialized by
88 * the latching of vblank->count below.
90 tslot
= vblank
->count
+ vblank_count_inc
;
91 vblanktimestamp(dev
, crtc
, 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_update_vblank_count - update the master vblank counter
110 * @crtc: counter to update
112 * Call back into the driver to update the appropriate vblank counter
113 * (specified by @crtc). Deal with wraparound, if it occurred, and
114 * update the last read value so we can deal with wraparound on the next
117 * Only necessary when going from off->on, to account for frames we
118 * didn't get an interrupt for.
120 * Note: caller must hold dev->vbl_lock since this reads & writes
121 * device vblank fields.
123 static void drm_update_vblank_count(struct drm_device
*dev
, int crtc
)
125 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[crtc
];
126 u32 cur_vblank
, diff
;
128 struct timeval t_vblank
;
131 * Interrupts were disabled prior to this call, so deal with counter
133 * NOTE! It's possible we lost a full dev->max_vblank_count + 1 events
134 * here if the register is small or we had vblank interrupts off for
137 * We repeat the hardware vblank counter & timestamp query until
138 * we get consistent results. This to prevent races between gpu
139 * updating its hardware counter while we are retrieving the
140 * corresponding vblank timestamp.
143 cur_vblank
= dev
->driver
->get_vblank_counter(dev
, crtc
);
144 rc
= drm_get_last_vbltimestamp(dev
, crtc
, &t_vblank
, 0);
145 } while (cur_vblank
!= dev
->driver
->get_vblank_counter(dev
, crtc
));
147 /* Deal with counter wrap */
148 diff
= cur_vblank
- vblank
->last
;
149 if (cur_vblank
< vblank
->last
) {
150 diff
+= dev
->max_vblank_count
+ 1;
152 DRM_DEBUG("last_vblank[%d]=0x%x, cur_vblank=0x%x => diff=0x%x\n",
153 crtc
, vblank
->last
, cur_vblank
, diff
);
156 DRM_DEBUG("updating vblank count on crtc %d, missed %d\n",
163 * Only reinitialize corresponding vblank timestamp if high-precision query
164 * available and didn't fail. Otherwise reinitialize delayed at next vblank
165 * interrupt and assign 0 for now, to mark the vblanktimestamp as invalid.
168 t_vblank
= (struct timeval
) {0, 0};
170 store_vblank(dev
, crtc
, diff
, &t_vblank
);
174 * Disable vblank irq's on crtc, make sure that last vblank count
175 * of hardware and corresponding consistent software vblank counter
176 * are preserved, even if there are any spurious vblank irq's after
179 static void vblank_disable_and_save(struct drm_device
*dev
, int crtc
)
181 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[crtc
];
182 unsigned long irqflags
;
186 struct timeval tvblank
;
187 int count
= DRM_TIMESTAMP_MAXRETRIES
;
189 /* Prevent vblank irq processing while disabling vblank irqs,
190 * so no updates of timestamps or count can happen after we've
191 * disabled. Needed to prevent races in case of delayed irq's.
193 spin_lock_irqsave(&dev
->vblank_time_lock
, irqflags
);
196 * If the vblank interrupt was already disabled update the count
197 * and timestamp to maintain the appearance that the counter
198 * has been ticking all along until this time. This makes the
199 * count account for the entire time between drm_vblank_on() and
202 * But only do this if precise vblank timestamps are available.
203 * Otherwise we might read a totally bogus timestamp since drivers
204 * lacking precise timestamp support rely upon sampling the system clock
205 * at vblank interrupt time. Which obviously won't work out well if the
206 * vblank interrupt is disabled.
208 if (!vblank
->enabled
&&
209 drm_get_last_vbltimestamp(dev
, crtc
, &tvblank
, 0)) {
210 drm_update_vblank_count(dev
, crtc
);
211 spin_unlock_irqrestore(&dev
->vblank_time_lock
, irqflags
);
216 * Only disable vblank interrupts if they're enabled. This avoids
217 * calling the ->disable_vblank() operation in atomic context with the
218 * hardware potentially runtime suspended.
220 if (vblank
->enabled
) {
221 dev
->driver
->disable_vblank(dev
, crtc
);
222 vblank
->enabled
= false;
225 /* No further vblank irq's will be processed after
226 * this point. Get current hardware vblank count and
227 * vblank timestamp, repeat until they are consistent.
229 * FIXME: There is still a race condition here and in
230 * drm_update_vblank_count() which can cause off-by-one
231 * reinitialization of software vblank counter. If gpu
232 * vblank counter doesn't increment exactly at the leading
233 * edge of a vblank interval, then we can lose 1 count if
234 * we happen to execute between start of vblank and the
235 * delayed gpu counter increment.
238 vblank
->last
= dev
->driver
->get_vblank_counter(dev
, crtc
);
239 vblrc
= drm_get_last_vbltimestamp(dev
, crtc
, &tvblank
, 0);
240 } while (vblank
->last
!= dev
->driver
->get_vblank_counter(dev
, crtc
) && (--count
) && vblrc
);
245 /* Compute time difference to stored timestamp of last vblank
246 * as updated by last invocation of drm_handle_vblank() in vblank irq.
248 vblcount
= vblank
->count
;
249 diff_ns
= timeval_to_ns(&tvblank
) -
250 timeval_to_ns(&vblanktimestamp(dev
, crtc
, vblcount
));
252 /* If there is at least 1 msec difference between the last stored
253 * timestamp and tvblank, then we are currently executing our
254 * disable inside a new vblank interval, the tvblank timestamp
255 * corresponds to this new vblank interval and the irq handler
256 * for this vblank didn't run yet and won't run due to our disable.
257 * Therefore we need to do the job of drm_handle_vblank() and
258 * increment the vblank counter by one to account for this vblank.
260 * Skip this step if there isn't any high precision timestamp
261 * available. In that case we can't account for this and just
264 if (vblrc
&& (abs64(diff_ns
) > 1000000))
265 store_vblank(dev
, crtc
, 1, &tvblank
);
267 spin_unlock_irqrestore(&dev
->vblank_time_lock
, irqflags
);
270 static void vblank_disable_fn(unsigned long arg
)
272 struct drm_vblank_crtc
*vblank
= (void *)arg
;
273 struct drm_device
*dev
= vblank
->dev
;
274 unsigned long irqflags
;
275 int crtc
= vblank
->crtc
;
277 if (!dev
->vblank_disable_allowed
)
280 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
281 if (atomic_read(&vblank
->refcount
) == 0 && vblank
->enabled
) {
282 DRM_DEBUG("disabling vblank on crtc %d\n", crtc
);
283 vblank_disable_and_save(dev
, crtc
);
285 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
289 * drm_vblank_cleanup - cleanup vblank support
292 * This function cleans up any resources allocated in drm_vblank_init.
294 void drm_vblank_cleanup(struct drm_device
*dev
)
298 /* Bail if the driver didn't call drm_vblank_init() */
299 if (dev
->num_crtcs
== 0)
302 for (crtc
= 0; crtc
< dev
->num_crtcs
; crtc
++) {
303 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[crtc
];
305 WARN_ON(vblank
->enabled
&&
306 drm_core_check_feature(dev
, DRIVER_MODESET
));
308 del_timer_sync(&vblank
->disable_timer
);
315 EXPORT_SYMBOL(drm_vblank_cleanup
);
318 * drm_vblank_init - initialize vblank support
320 * @num_crtcs: number of crtcs supported by @dev
322 * This function initializes vblank support for @num_crtcs display pipelines.
325 * Zero on success or a negative error code on failure.
327 int drm_vblank_init(struct drm_device
*dev
, int num_crtcs
)
329 int i
, ret
= -ENOMEM
;
331 spin_lock_init(&dev
->vbl_lock
);
332 spin_lock_init(&dev
->vblank_time_lock
);
334 dev
->num_crtcs
= num_crtcs
;
336 dev
->vblank
= kcalloc(num_crtcs
, sizeof(*dev
->vblank
), GFP_KERNEL
);
340 for (i
= 0; i
< num_crtcs
; i
++) {
341 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[i
];
345 init_waitqueue_head(&vblank
->queue
);
346 setup_timer(&vblank
->disable_timer
, vblank_disable_fn
,
347 (unsigned long)vblank
);
350 DRM_INFO("Supports vblank timestamp caching Rev 2 (21.10.2013).\n");
352 /* Driver specific high-precision vblank timestamping supported? */
353 if (dev
->driver
->get_vblank_timestamp
)
354 DRM_INFO("Driver supports precise vblank timestamp query.\n");
356 DRM_INFO("No driver support for vblank timestamp query.\n");
358 /* Must have precise timestamping for reliable vblank instant disable */
359 if (dev
->vblank_disable_immediate
&& !dev
->driver
->get_vblank_timestamp
) {
360 dev
->vblank_disable_immediate
= false;
361 DRM_INFO("Setting vblank_disable_immediate to false because "
362 "get_vblank_timestamp == NULL\n");
365 dev
->vblank_disable_allowed
= false;
373 EXPORT_SYMBOL(drm_vblank_init
);
375 static void drm_irq_vgaarb_nokms(void *cookie
, bool state
)
377 struct drm_device
*dev
= cookie
;
379 if (dev
->driver
->vgaarb_irq
) {
380 dev
->driver
->vgaarb_irq(dev
, state
);
384 if (!dev
->irq_enabled
)
388 if (dev
->driver
->irq_uninstall
)
389 dev
->driver
->irq_uninstall(dev
);
391 if (dev
->driver
->irq_preinstall
)
392 dev
->driver
->irq_preinstall(dev
);
393 if (dev
->driver
->irq_postinstall
)
394 dev
->driver
->irq_postinstall(dev
);
399 * drm_irq_install - install IRQ handler
401 * @irq: IRQ number to install the handler for
403 * Initializes the IRQ related data. Installs the handler, calling the driver
404 * irq_preinstall() and irq_postinstall() functions before and after the
407 * This is the simplified helper interface provided for drivers with no special
408 * needs. Drivers which need to install interrupt handlers for multiple
409 * interrupts must instead set drm_device->irq_enabled to signal the DRM core
410 * that vblank interrupts are available.
413 * Zero on success or a negative error code on failure.
415 int drm_irq_install(struct drm_device
*dev
, int irq
)
418 unsigned long sh_flags
= 0;
420 if (!drm_core_check_feature(dev
, DRIVER_HAVE_IRQ
))
426 /* Driver must have been initialized */
427 if (!dev
->dev_private
)
430 if (dev
->irq_enabled
)
432 dev
->irq_enabled
= true;
434 DRM_DEBUG("irq=%d\n", irq
);
436 /* Before installing handler */
437 if (dev
->driver
->irq_preinstall
)
438 dev
->driver
->irq_preinstall(dev
);
440 /* Install handler */
441 if (drm_core_check_feature(dev
, DRIVER_IRQ_SHARED
))
442 sh_flags
= IRQF_SHARED
;
444 ret
= request_irq(irq
, dev
->driver
->irq_handler
,
445 sh_flags
, dev
->driver
->name
, dev
);
448 dev
->irq_enabled
= false;
452 if (!drm_core_check_feature(dev
, DRIVER_MODESET
))
453 vga_client_register(dev
->pdev
, (void *)dev
, drm_irq_vgaarb_nokms
, NULL
);
455 /* After installing handler */
456 if (dev
->driver
->irq_postinstall
)
457 ret
= dev
->driver
->irq_postinstall(dev
);
460 dev
->irq_enabled
= false;
461 if (!drm_core_check_feature(dev
, DRIVER_MODESET
))
462 vga_client_register(dev
->pdev
, NULL
, NULL
, NULL
);
470 EXPORT_SYMBOL(drm_irq_install
);
473 * drm_irq_uninstall - uninstall the IRQ handler
476 * Calls the driver's irq_uninstall() function and unregisters the IRQ handler.
477 * This should only be called by drivers which used drm_irq_install() to set up
478 * their interrupt handler. Other drivers must only reset
479 * drm_device->irq_enabled to false.
481 * Note that for kernel modesetting drivers it is a bug if this function fails.
482 * The sanity checks are only to catch buggy user modesetting drivers which call
483 * the same function through an ioctl.
486 * Zero on success or a negative error code on failure.
488 int drm_irq_uninstall(struct drm_device
*dev
)
490 unsigned long irqflags
;
494 if (!drm_core_check_feature(dev
, DRIVER_HAVE_IRQ
))
497 irq_enabled
= dev
->irq_enabled
;
498 dev
->irq_enabled
= false;
501 * Wake up any waiters so they don't hang. This is just to paper over
502 * isssues for UMS drivers which aren't in full control of their
503 * vblank/irq handling. KMS drivers must ensure that vblanks are all
504 * disabled when uninstalling the irq handler.
506 if (dev
->num_crtcs
) {
507 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
508 for (i
= 0; i
< dev
->num_crtcs
; i
++) {
509 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[i
];
511 if (!vblank
->enabled
)
514 WARN_ON(drm_core_check_feature(dev
, DRIVER_MODESET
));
516 vblank_disable_and_save(dev
, i
);
517 wake_up(&vblank
->queue
);
519 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
525 DRM_DEBUG("irq=%d\n", dev
->irq
);
527 if (!drm_core_check_feature(dev
, DRIVER_MODESET
))
528 vga_client_register(dev
->pdev
, NULL
, NULL
, NULL
);
530 if (dev
->driver
->irq_uninstall
)
531 dev
->driver
->irq_uninstall(dev
);
533 free_irq(dev
->irq
, dev
);
537 EXPORT_SYMBOL(drm_irq_uninstall
);
542 * \param inode device inode.
543 * \param file_priv DRM file private.
544 * \param cmd command.
545 * \param arg user argument, pointing to a drm_control structure.
546 * \return zero on success or a negative number on failure.
548 * Calls irq_install() or irq_uninstall() according to \p arg.
550 int drm_control(struct drm_device
*dev
, void *data
,
551 struct drm_file
*file_priv
)
553 struct drm_control
*ctl
= data
;
556 /* if we haven't irq we fallback for compatibility reasons -
557 * this used to be a separate function in drm_dma.h
560 if (!drm_core_check_feature(dev
, DRIVER_HAVE_IRQ
))
562 if (drm_core_check_feature(dev
, DRIVER_MODESET
))
564 /* UMS was only ever support on pci devices. */
565 if (WARN_ON(!dev
->pdev
))
569 case DRM_INST_HANDLER
:
570 irq
= dev
->pdev
->irq
;
572 if (dev
->if_version
< DRM_IF_VERSION(1, 2) &&
575 mutex_lock(&dev
->struct_mutex
);
576 ret
= drm_irq_install(dev
, irq
);
577 mutex_unlock(&dev
->struct_mutex
);
580 case DRM_UNINST_HANDLER
:
581 mutex_lock(&dev
->struct_mutex
);
582 ret
= drm_irq_uninstall(dev
);
583 mutex_unlock(&dev
->struct_mutex
);
592 * drm_calc_timestamping_constants - calculate vblank timestamp constants
593 * @crtc: drm_crtc whose timestamp constants should be updated.
594 * @mode: display mode containing the scanout timings
596 * Calculate and store various constants which are later
597 * needed by vblank and swap-completion timestamping, e.g,
598 * by drm_calc_vbltimestamp_from_scanoutpos(). They are
599 * derived from CRTC's true scanout timing, so they take
600 * things like panel scaling or other adjustments into account.
602 void drm_calc_timestamping_constants(struct drm_crtc
*crtc
,
603 const struct drm_display_mode
*mode
)
605 int linedur_ns
= 0, pixeldur_ns
= 0, framedur_ns
= 0;
606 int dotclock
= mode
->crtc_clock
;
608 /* Valid dotclock? */
610 int frame_size
= mode
->crtc_htotal
* mode
->crtc_vtotal
;
613 * Convert scanline length in pixels and video
614 * dot clock to line duration, frame duration
615 * and pixel duration in nanoseconds:
617 pixeldur_ns
= 1000000 / dotclock
;
618 linedur_ns
= div_u64((u64
) mode
->crtc_htotal
* 1000000, dotclock
);
619 framedur_ns
= div_u64((u64
) frame_size
* 1000000, dotclock
);
622 * Fields of interlaced scanout modes are only half a frame duration.
624 if (mode
->flags
& DRM_MODE_FLAG_INTERLACE
)
627 DRM_ERROR("crtc %d: Can't calculate constants, dotclock = 0!\n",
630 crtc
->pixeldur_ns
= pixeldur_ns
;
631 crtc
->linedur_ns
= linedur_ns
;
632 crtc
->framedur_ns
= framedur_ns
;
634 DRM_DEBUG("crtc %d: hwmode: htotal %d, vtotal %d, vdisplay %d\n",
635 crtc
->base
.id
, mode
->crtc_htotal
,
636 mode
->crtc_vtotal
, mode
->crtc_vdisplay
);
637 DRM_DEBUG("crtc %d: clock %d kHz framedur %d linedur %d, pixeldur %d\n",
638 crtc
->base
.id
, dotclock
, framedur_ns
,
639 linedur_ns
, pixeldur_ns
);
641 EXPORT_SYMBOL(drm_calc_timestamping_constants
);
644 * drm_calc_vbltimestamp_from_scanoutpos - precise vblank timestamp helper
646 * @crtc: Which CRTC's vblank timestamp to retrieve
647 * @max_error: Desired maximum allowable error in timestamps (nanosecs)
648 * On return contains true maximum error of timestamp
649 * @vblank_time: Pointer to struct timeval which should receive the timestamp
650 * @flags: Flags to pass to driver:
652 * DRM_CALLED_FROM_VBLIRQ = If function is called from vbl IRQ handler
653 * @refcrtc: CRTC which defines scanout timing
654 * @mode: mode which defines the scanout timings
656 * Implements calculation of exact vblank timestamps from given drm_display_mode
657 * timings and current video scanout position of a CRTC. This can be called from
658 * within get_vblank_timestamp() implementation of a kms driver to implement the
659 * actual timestamping.
661 * Should return timestamps conforming to the OML_sync_control OpenML
662 * extension specification. The timestamp corresponds to the end of
663 * the vblank interval, aka start of scanout of topmost-leftmost display
664 * pixel in the following video frame.
666 * Requires support for optional dev->driver->get_scanout_position()
667 * in kms driver, plus a bit of setup code to provide a drm_display_mode
668 * that corresponds to the true scanout timing.
670 * The current implementation only handles standard video modes. It
671 * returns as no operation if a doublescan or interlaced video mode is
672 * active. Higher level code is expected to handle this.
675 * Negative value on error, failure or if not supported in current
678 * -EINVAL - Invalid CRTC.
679 * -EAGAIN - Temporary unavailable, e.g., called before initial modeset.
680 * -ENOTSUPP - Function not supported in current display mode.
681 * -EIO - Failed, e.g., due to failed scanout position query.
683 * Returns or'ed positive status flags on success:
685 * DRM_VBLANKTIME_SCANOUTPOS_METHOD - Signal this method used for timestamping.
686 * DRM_VBLANKTIME_INVBL - Timestamp taken while scanout was in vblank interval.
689 int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device
*dev
, int crtc
,
691 struct timeval
*vblank_time
,
693 const struct drm_crtc
*refcrtc
,
694 const struct drm_display_mode
*mode
)
696 struct timeval tv_etime
;
697 ktime_t stime
, etime
;
700 int framedur_ns
, linedur_ns
, pixeldur_ns
, delta_ns
, duration_ns
;
703 if (crtc
< 0 || crtc
>= dev
->num_crtcs
) {
704 DRM_ERROR("Invalid crtc %d\n", crtc
);
708 /* Scanout position query not supported? Should not happen. */
709 if (!dev
->driver
->get_scanout_position
) {
710 DRM_ERROR("Called from driver w/o get_scanout_position()!?\n");
714 /* Durations of frames, lines, pixels in nanoseconds. */
715 framedur_ns
= refcrtc
->framedur_ns
;
716 linedur_ns
= refcrtc
->linedur_ns
;
717 pixeldur_ns
= refcrtc
->pixeldur_ns
;
719 /* If mode timing undefined, just return as no-op:
720 * Happens during initial modesetting of a crtc.
722 if (framedur_ns
== 0) {
723 DRM_DEBUG("crtc %d: Noop due to uninitialized mode.\n", crtc
);
727 /* Get current scanout position with system timestamp.
728 * Repeat query up to DRM_TIMESTAMP_MAXRETRIES times
729 * if single query takes longer than max_error nanoseconds.
731 * This guarantees a tight bound on maximum error if
732 * code gets preempted or delayed for some reason.
734 for (i
= 0; i
< DRM_TIMESTAMP_MAXRETRIES
; i
++) {
736 * Get vertical and horizontal scanout position vpos, hpos,
737 * and bounding timestamps stime, etime, pre/post query.
739 vbl_status
= dev
->driver
->get_scanout_position(dev
, crtc
, flags
, &vpos
,
740 &hpos
, &stime
, &etime
);
742 /* Return as no-op if scanout query unsupported or failed. */
743 if (!(vbl_status
& DRM_SCANOUTPOS_VALID
)) {
744 DRM_DEBUG("crtc %d : scanoutpos query failed [%d].\n",
749 /* Compute uncertainty in timestamp of scanout position query. */
750 duration_ns
= ktime_to_ns(etime
) - ktime_to_ns(stime
);
752 /* Accept result with < max_error nsecs timing uncertainty. */
753 if (duration_ns
<= *max_error
)
757 /* Noisy system timing? */
758 if (i
== DRM_TIMESTAMP_MAXRETRIES
) {
759 DRM_DEBUG("crtc %d: Noisy timestamp %d us > %d us [%d reps].\n",
760 crtc
, duration_ns
/1000, *max_error
/1000, i
);
763 /* Return upper bound of timestamp precision error. */
764 *max_error
= duration_ns
;
766 /* Check if in vblank area:
767 * vpos is >=0 in video scanout area, but negative
768 * within vblank area, counting down the number of lines until
771 invbl
= vbl_status
& DRM_SCANOUTPOS_IN_VBLANK
;
773 /* Convert scanout position into elapsed time at raw_time query
774 * since start of scanout at first display scanline. delta_ns
775 * can be negative if start of scanout hasn't happened yet.
777 delta_ns
= vpos
* linedur_ns
+ hpos
* pixeldur_ns
;
779 if (!drm_timestamp_monotonic
)
780 etime
= ktime_mono_to_real(etime
);
782 /* save this only for debugging purposes */
783 tv_etime
= ktime_to_timeval(etime
);
784 /* Subtract time delta from raw timestamp to get final
785 * vblank_time timestamp for end of vblank.
788 etime
= ktime_add_ns(etime
, -delta_ns
);
790 etime
= ktime_sub_ns(etime
, delta_ns
);
791 *vblank_time
= ktime_to_timeval(etime
);
793 DRM_DEBUG("crtc %d : v %d p(%d,%d)@ %ld.%ld -> %ld.%ld [e %d us, %d rep]\n",
794 crtc
, (int)vbl_status
, hpos
, vpos
,
795 (long)tv_etime
.tv_sec
, (long)tv_etime
.tv_usec
,
796 (long)vblank_time
->tv_sec
, (long)vblank_time
->tv_usec
,
797 duration_ns
/1000, i
);
799 vbl_status
= DRM_VBLANKTIME_SCANOUTPOS_METHOD
;
801 vbl_status
|= DRM_VBLANKTIME_IN_VBLANK
;
805 EXPORT_SYMBOL(drm_calc_vbltimestamp_from_scanoutpos
);
807 static struct timeval
get_drm_timestamp(void)
811 now
= drm_timestamp_monotonic
? ktime_get() : ktime_get_real();
812 return ktime_to_timeval(now
);
816 * drm_get_last_vbltimestamp - retrieve raw timestamp for the most recent
819 * @crtc: which CRTC's vblank timestamp to retrieve
820 * @tvblank: Pointer to target struct timeval which should receive the timestamp
821 * @flags: Flags to pass to driver:
823 * DRM_CALLED_FROM_VBLIRQ = If function is called from vbl IRQ handler
825 * Fetches the system timestamp corresponding to the time of the most recent
826 * vblank interval on specified CRTC. May call into kms-driver to
827 * compute the timestamp with a high-precision GPU specific method.
829 * Returns zero if timestamp originates from uncorrected do_gettimeofday()
830 * call, i.e., it isn't very precisely locked to the true vblank.
833 * True if timestamp is considered to be very precise, false otherwise.
836 drm_get_last_vbltimestamp(struct drm_device
*dev
, int crtc
,
837 struct timeval
*tvblank
, unsigned flags
)
841 /* Define requested maximum error on timestamps (nanoseconds). */
842 int max_error
= (int) drm_timestamp_precision
* 1000;
844 /* Query driver if possible and precision timestamping enabled. */
845 if (dev
->driver
->get_vblank_timestamp
&& (max_error
> 0)) {
846 ret
= dev
->driver
->get_vblank_timestamp(dev
, crtc
, &max_error
,
852 /* GPU high precision timestamp query unsupported or failed.
853 * Return current monotonic/gettimeofday timestamp as best estimate.
855 *tvblank
= get_drm_timestamp();
861 * drm_vblank_count - retrieve "cooked" vblank counter value
863 * @crtc: which counter to retrieve
865 * Fetches the "cooked" vblank count value that represents the number of
866 * vblank events since the system was booted, including lost events due to
867 * modesetting activity.
869 * This is the legacy version of drm_crtc_vblank_count().
872 * The software vblank counter.
874 u32
drm_vblank_count(struct drm_device
*dev
, int crtc
)
876 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[crtc
];
878 if (WARN_ON(crtc
>= dev
->num_crtcs
))
880 return vblank
->count
;
882 EXPORT_SYMBOL(drm_vblank_count
);
885 * drm_crtc_vblank_count - retrieve "cooked" vblank counter value
886 * @crtc: which counter to retrieve
888 * Fetches the "cooked" vblank count value that represents the number of
889 * vblank events since the system was booted, including lost events due to
890 * modesetting activity.
892 * This is the native KMS version of drm_vblank_count().
895 * The software vblank counter.
897 u32
drm_crtc_vblank_count(struct drm_crtc
*crtc
)
899 return drm_vblank_count(crtc
->dev
, drm_crtc_index(crtc
));
901 EXPORT_SYMBOL(drm_crtc_vblank_count
);
904 * drm_vblank_count_and_time - retrieve "cooked" vblank counter value
905 * and the system timestamp corresponding to that vblank counter value.
908 * @crtc: which counter to retrieve
909 * @vblanktime: Pointer to struct timeval to receive the vblank timestamp.
911 * Fetches the "cooked" vblank count value that represents the number of
912 * vblank events since the system was booted, including lost events due to
913 * modesetting activity. Returns corresponding system timestamp of the time
914 * of the vblank interval that corresponds to the current vblank counter value.
916 u32
drm_vblank_count_and_time(struct drm_device
*dev
, int crtc
,
917 struct timeval
*vblanktime
)
919 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[crtc
];
922 if (WARN_ON(crtc
>= dev
->num_crtcs
))
926 * Vblank timestamps are read lockless. To ensure consistency the vblank
927 * counter is rechecked and ordering is ensured using memory barriers.
928 * This works like a seqlock. The write-side barriers are in store_vblank.
931 cur_vblank
= vblank
->count
;
933 *vblanktime
= vblanktimestamp(dev
, crtc
, cur_vblank
);
935 } while (cur_vblank
!= vblank
->count
);
939 EXPORT_SYMBOL(drm_vblank_count_and_time
);
941 static void send_vblank_event(struct drm_device
*dev
,
942 struct drm_pending_vblank_event
*e
,
943 unsigned long seq
, struct timeval
*now
)
945 WARN_ON_SMP(!spin_is_locked(&dev
->event_lock
));
946 e
->event
.sequence
= seq
;
947 e
->event
.tv_sec
= now
->tv_sec
;
948 e
->event
.tv_usec
= now
->tv_usec
;
950 list_add_tail(&e
->base
.link
,
951 &e
->base
.file_priv
->event_list
);
952 wake_up_interruptible(&e
->base
.file_priv
->event_wait
);
953 trace_drm_vblank_event_delivered(e
->base
.pid
, e
->pipe
,
958 * drm_send_vblank_event - helper to send vblank event after pageflip
960 * @crtc: CRTC in question
961 * @e: the event to send
963 * Updates sequence # and timestamp on event, and sends it to userspace.
964 * Caller must hold event lock.
966 * This is the legacy version of drm_crtc_send_vblank_event().
968 void drm_send_vblank_event(struct drm_device
*dev
, int crtc
,
969 struct drm_pending_vblank_event
*e
)
975 seq
= drm_vblank_count_and_time(dev
, crtc
, &now
);
979 now
= get_drm_timestamp();
982 send_vblank_event(dev
, e
, seq
, &now
);
984 EXPORT_SYMBOL(drm_send_vblank_event
);
987 * drm_crtc_send_vblank_event - helper to send vblank event after pageflip
988 * @crtc: the source CRTC of the vblank event
989 * @e: the event to send
991 * Updates sequence # and timestamp on event, and sends it to userspace.
992 * Caller must hold event lock.
994 * This is the native KMS version of drm_send_vblank_event().
996 void drm_crtc_send_vblank_event(struct drm_crtc
*crtc
,
997 struct drm_pending_vblank_event
*e
)
999 drm_send_vblank_event(crtc
->dev
, drm_crtc_index(crtc
), e
);
1001 EXPORT_SYMBOL(drm_crtc_send_vblank_event
);
1004 * drm_vblank_enable - enable the vblank interrupt on a CRTC
1006 * @crtc: CRTC in question
1008 static int drm_vblank_enable(struct drm_device
*dev
, int crtc
)
1010 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[crtc
];
1013 assert_spin_locked(&dev
->vbl_lock
);
1015 spin_lock(&dev
->vblank_time_lock
);
1017 if (!vblank
->enabled
) {
1019 * Enable vblank irqs under vblank_time_lock protection.
1020 * All vblank count & timestamp updates are held off
1021 * until we are done reinitializing master counter and
1022 * timestamps. Filtercode in drm_handle_vblank() will
1023 * prevent double-accounting of same vblank interval.
1025 ret
= dev
->driver
->enable_vblank(dev
, crtc
);
1026 DRM_DEBUG("enabling vblank on crtc %d, ret: %d\n", crtc
, ret
);
1028 atomic_dec(&vblank
->refcount
);
1030 vblank
->enabled
= true;
1031 drm_update_vblank_count(dev
, crtc
);
1035 spin_unlock(&dev
->vblank_time_lock
);
1041 * drm_vblank_get - get a reference count on vblank events
1043 * @crtc: which CRTC to own
1045 * Acquire a reference count on vblank events to avoid having them disabled
1048 * This is the legacy version of drm_crtc_vblank_get().
1051 * Zero on success, nonzero on failure.
1053 int drm_vblank_get(struct drm_device
*dev
, int crtc
)
1055 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[crtc
];
1056 unsigned long irqflags
;
1059 if (!dev
->num_crtcs
)
1062 if (WARN_ON(crtc
>= dev
->num_crtcs
))
1065 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
1066 /* Going from 0->1 means we have to enable interrupts again */
1067 if (atomic_add_return(1, &vblank
->refcount
) == 1) {
1068 ret
= drm_vblank_enable(dev
, crtc
);
1070 if (!vblank
->enabled
) {
1071 atomic_dec(&vblank
->refcount
);
1075 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
1079 EXPORT_SYMBOL(drm_vblank_get
);
1082 * drm_crtc_vblank_get - get a reference count on vblank events
1083 * @crtc: which CRTC to own
1085 * Acquire a reference count on vblank events to avoid having them disabled
1088 * This is the native kms version of drm_vblank_get().
1091 * Zero on success, nonzero on failure.
1093 int drm_crtc_vblank_get(struct drm_crtc
*crtc
)
1095 return drm_vblank_get(crtc
->dev
, drm_crtc_index(crtc
));
1097 EXPORT_SYMBOL(drm_crtc_vblank_get
);
1100 * drm_vblank_put - give up ownership of vblank events
1102 * @crtc: which counter to give up
1104 * Release ownership of a given vblank counter, turning off interrupts
1105 * if possible. Disable interrupts after drm_vblank_offdelay milliseconds.
1107 * This is the legacy version of drm_crtc_vblank_put().
1109 void drm_vblank_put(struct drm_device
*dev
, int crtc
)
1111 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[crtc
];
1113 if (WARN_ON(atomic_read(&vblank
->refcount
) == 0))
1116 if (WARN_ON(crtc
>= dev
->num_crtcs
))
1119 /* Last user schedules interrupt disable */
1120 if (atomic_dec_and_test(&vblank
->refcount
)) {
1121 if (drm_vblank_offdelay
== 0)
1123 else if (dev
->vblank_disable_immediate
|| drm_vblank_offdelay
< 0)
1124 vblank_disable_fn((unsigned long)vblank
);
1126 mod_timer(&vblank
->disable_timer
,
1127 jiffies
+ ((drm_vblank_offdelay
* HZ
)/1000));
1130 EXPORT_SYMBOL(drm_vblank_put
);
1133 * drm_crtc_vblank_put - give up ownership of vblank events
1134 * @crtc: which counter to give up
1136 * Release ownership of a given vblank counter, turning off interrupts
1137 * if possible. Disable interrupts after drm_vblank_offdelay milliseconds.
1139 * This is the native kms version of drm_vblank_put().
1141 void drm_crtc_vblank_put(struct drm_crtc
*crtc
)
1143 drm_vblank_put(crtc
->dev
, drm_crtc_index(crtc
));
1145 EXPORT_SYMBOL(drm_crtc_vblank_put
);
1148 * drm_wait_one_vblank - wait for one vblank
1152 * This waits for one vblank to pass on @crtc, using the irq driver interfaces.
1153 * It is a failure to call this when the vblank irq for @crtc is disabled, e.g.
1154 * due to lack of driver support or because the crtc is off.
1156 void drm_wait_one_vblank(struct drm_device
*dev
, int crtc
)
1161 ret
= drm_vblank_get(dev
, crtc
);
1162 if (WARN(ret
, "vblank not available on crtc %i, ret=%i\n", crtc
, ret
))
1165 last
= drm_vblank_count(dev
, crtc
);
1167 ret
= wait_event_timeout(dev
->vblank
[crtc
].queue
,
1168 last
!= drm_vblank_count(dev
, crtc
),
1169 msecs_to_jiffies(100));
1171 WARN(ret
== 0, "vblank wait timed out on crtc %i\n", crtc
);
1173 drm_vblank_put(dev
, crtc
);
1175 EXPORT_SYMBOL(drm_wait_one_vblank
);
1178 * drm_crtc_wait_one_vblank - wait for one vblank
1181 * This waits for one vblank to pass on @crtc, using the irq driver interfaces.
1182 * It is a failure to call this when the vblank irq for @crtc is disabled, e.g.
1183 * due to lack of driver support or because the crtc is off.
1185 void drm_crtc_wait_one_vblank(struct drm_crtc
*crtc
)
1187 drm_wait_one_vblank(crtc
->dev
, drm_crtc_index(crtc
));
1189 EXPORT_SYMBOL(drm_crtc_wait_one_vblank
);
1192 * drm_vblank_off - disable vblank events on a CRTC
1194 * @crtc: CRTC in question
1196 * Drivers can use this function to shut down the vblank interrupt handling when
1197 * disabling a crtc. This function ensures that the latest vblank frame count is
1198 * stored so that drm_vblank_on() can restore it again.
1200 * Drivers must use this function when the hardware vblank counter can get
1201 * reset, e.g. when suspending.
1203 * This is the legacy version of drm_crtc_vblank_off().
1205 void drm_vblank_off(struct drm_device
*dev
, int crtc
)
1207 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[crtc
];
1208 struct drm_pending_vblank_event
*e
, *t
;
1210 unsigned long irqflags
;
1213 if (WARN_ON(crtc
>= dev
->num_crtcs
))
1216 spin_lock_irqsave(&dev
->event_lock
, irqflags
);
1218 spin_lock(&dev
->vbl_lock
);
1219 vblank_disable_and_save(dev
, crtc
);
1220 wake_up(&vblank
->queue
);
1223 * Prevent subsequent drm_vblank_get() from re-enabling
1224 * the vblank interrupt by bumping the refcount.
1226 if (!vblank
->inmodeset
) {
1227 atomic_inc(&vblank
->refcount
);
1228 vblank
->inmodeset
= 1;
1230 spin_unlock(&dev
->vbl_lock
);
1232 /* Send any queued vblank events, lest the natives grow disquiet */
1233 seq
= drm_vblank_count_and_time(dev
, crtc
, &now
);
1235 list_for_each_entry_safe(e
, t
, &dev
->vblank_event_list
, base
.link
) {
1236 if (e
->pipe
!= crtc
)
1238 DRM_DEBUG("Sending premature vblank event on disable: \
1239 wanted %d, current %d\n",
1240 e
->event
.sequence
, seq
);
1241 list_del(&e
->base
.link
);
1242 drm_vblank_put(dev
, e
->pipe
);
1243 send_vblank_event(dev
, e
, seq
, &now
);
1245 spin_unlock_irqrestore(&dev
->event_lock
, irqflags
);
1247 EXPORT_SYMBOL(drm_vblank_off
);
1250 * drm_crtc_vblank_off - disable vblank events on a CRTC
1251 * @crtc: CRTC in question
1253 * Drivers can use this function to shut down the vblank interrupt handling when
1254 * disabling a crtc. This function ensures that the latest vblank frame count is
1255 * stored so that drm_vblank_on can restore it again.
1257 * Drivers must use this function when the hardware vblank counter can get
1258 * reset, e.g. when suspending.
1260 * This is the native kms version of drm_vblank_off().
1262 void drm_crtc_vblank_off(struct drm_crtc
*crtc
)
1264 drm_vblank_off(crtc
->dev
, drm_crtc_index(crtc
));
1266 EXPORT_SYMBOL(drm_crtc_vblank_off
);
1269 * drm_crtc_vblank_reset - reset vblank state to off on a CRTC
1270 * @crtc: CRTC in question
1272 * Drivers can use this function to reset the vblank state to off at load time.
1273 * Drivers should use this together with the drm_crtc_vblank_off() and
1274 * drm_crtc_vblank_on() functions. The difference compared to
1275 * drm_crtc_vblank_off() is that this function doesn't save the vblank counter
1276 * and hence doesn't need to call any driver hooks.
1278 void drm_crtc_vblank_reset(struct drm_crtc
*drm_crtc
)
1280 struct drm_device
*dev
= drm_crtc
->dev
;
1281 unsigned long irqflags
;
1282 int crtc
= drm_crtc_index(drm_crtc
);
1283 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[crtc
];
1285 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
1287 * Prevent subsequent drm_vblank_get() from enabling the vblank
1288 * interrupt by bumping the refcount.
1290 if (!vblank
->inmodeset
) {
1291 atomic_inc(&vblank
->refcount
);
1292 vblank
->inmodeset
= 1;
1294 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
1296 WARN_ON(!list_empty(&dev
->vblank_event_list
));
1298 EXPORT_SYMBOL(drm_crtc_vblank_reset
);
1301 * drm_vblank_on - enable vblank events on a CRTC
1303 * @crtc: CRTC in question
1305 * This functions restores the vblank interrupt state captured with
1306 * drm_vblank_off() again. Note that calls to drm_vblank_on() and
1307 * drm_vblank_off() can be unbalanced and so can also be unconditionally called
1308 * in driver load code to reflect the current hardware state of the crtc.
1310 * This is the legacy version of drm_crtc_vblank_on().
1312 void drm_vblank_on(struct drm_device
*dev
, int crtc
)
1314 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[crtc
];
1315 unsigned long irqflags
;
1317 if (WARN_ON(crtc
>= dev
->num_crtcs
))
1320 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
1321 /* Drop our private "prevent drm_vblank_get" refcount */
1322 if (vblank
->inmodeset
) {
1323 atomic_dec(&vblank
->refcount
);
1324 vblank
->inmodeset
= 0;
1328 * sample the current counter to avoid random jumps
1329 * when drm_vblank_enable() applies the diff
1331 * -1 to make sure user will never see the same
1332 * vblank counter value before and after a modeset
1335 (dev
->driver
->get_vblank_counter(dev
, crtc
) - 1) &
1336 dev
->max_vblank_count
;
1338 * re-enable interrupts if there are users left, or the
1339 * user wishes vblank interrupts to be enabled all the time.
1341 if (atomic_read(&vblank
->refcount
) != 0 ||
1342 (!dev
->vblank_disable_immediate
&& drm_vblank_offdelay
== 0))
1343 WARN_ON(drm_vblank_enable(dev
, crtc
));
1344 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
1346 EXPORT_SYMBOL(drm_vblank_on
);
1349 * drm_crtc_vblank_on - enable vblank events on a CRTC
1350 * @crtc: CRTC in question
1352 * This functions restores the vblank interrupt state captured with
1353 * drm_vblank_off() again. Note that calls to drm_vblank_on() and
1354 * drm_vblank_off() can be unbalanced and so can also be unconditionally called
1355 * in driver load code to reflect the current hardware state of the crtc.
1357 * This is the native kms version of drm_vblank_on().
1359 void drm_crtc_vblank_on(struct drm_crtc
*crtc
)
1361 drm_vblank_on(crtc
->dev
, drm_crtc_index(crtc
));
1363 EXPORT_SYMBOL(drm_crtc_vblank_on
);
1366 * drm_vblank_pre_modeset - account for vblanks across mode sets
1368 * @crtc: CRTC in question
1370 * Account for vblank events across mode setting events, which will likely
1371 * reset the hardware frame counter.
1373 * This is done by grabbing a temporary vblank reference to ensure that the
1374 * vblank interrupt keeps running across the modeset sequence. With this the
1375 * software-side vblank frame counting will ensure that there are no jumps or
1378 * Unfortunately this approach is racy and also doesn't work when the vblank
1379 * interrupt stops running, e.g. across system suspend resume. It is therefore
1380 * highly recommended that drivers use the newer drm_vblank_off() and
1381 * drm_vblank_on() instead. drm_vblank_pre_modeset() only works correctly when
1382 * using "cooked" software vblank frame counters and not relying on any hardware
1385 * Drivers must call drm_vblank_post_modeset() when re-enabling the same crtc
1388 void drm_vblank_pre_modeset(struct drm_device
*dev
, int crtc
)
1390 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[crtc
];
1392 /* vblank is not initialized (IRQ not installed ?), or has been freed */
1393 if (!dev
->num_crtcs
)
1396 if (WARN_ON(crtc
>= dev
->num_crtcs
))
1400 * To avoid all the problems that might happen if interrupts
1401 * were enabled/disabled around or between these calls, we just
1402 * have the kernel take a reference on the CRTC (just once though
1403 * to avoid corrupting the count if multiple, mismatch calls occur),
1404 * so that interrupts remain enabled in the interim.
1406 if (!vblank
->inmodeset
) {
1407 vblank
->inmodeset
= 0x1;
1408 if (drm_vblank_get(dev
, crtc
) == 0)
1409 vblank
->inmodeset
|= 0x2;
1412 EXPORT_SYMBOL(drm_vblank_pre_modeset
);
1415 * drm_vblank_post_modeset - undo drm_vblank_pre_modeset changes
1417 * @crtc: CRTC in question
1419 * This function again drops the temporary vblank reference acquired in
1420 * drm_vblank_pre_modeset.
1422 void drm_vblank_post_modeset(struct drm_device
*dev
, int crtc
)
1424 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[crtc
];
1425 unsigned long irqflags
;
1427 /* vblank is not initialized (IRQ not installed ?), or has been freed */
1428 if (!dev
->num_crtcs
)
1431 if (vblank
->inmodeset
) {
1432 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
1433 dev
->vblank_disable_allowed
= true;
1434 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
1436 if (vblank
->inmodeset
& 0x2)
1437 drm_vblank_put(dev
, crtc
);
1439 vblank
->inmodeset
= 0;
1442 EXPORT_SYMBOL(drm_vblank_post_modeset
);
1445 * drm_modeset_ctl - handle vblank event counter changes across mode switch
1446 * @DRM_IOCTL_ARGS: standard ioctl arguments
1448 * Applications should call the %_DRM_PRE_MODESET and %_DRM_POST_MODESET
1449 * ioctls around modesetting so that any lost vblank events are accounted for.
1451 * Generally the counter will reset across mode sets. If interrupts are
1452 * enabled around this call, we don't have to do anything since the counter
1453 * will have already been incremented.
1455 int drm_modeset_ctl(struct drm_device
*dev
, void *data
,
1456 struct drm_file
*file_priv
)
1458 struct drm_modeset_ctl
*modeset
= data
;
1461 /* If drm_vblank_init() hasn't been called yet, just no-op */
1462 if (!dev
->num_crtcs
)
1465 /* KMS drivers handle this internally */
1466 if (drm_core_check_feature(dev
, DRIVER_MODESET
))
1469 crtc
= modeset
->crtc
;
1470 if (crtc
>= dev
->num_crtcs
)
1473 switch (modeset
->cmd
) {
1474 case _DRM_PRE_MODESET
:
1475 drm_vblank_pre_modeset(dev
, crtc
);
1477 case _DRM_POST_MODESET
:
1478 drm_vblank_post_modeset(dev
, crtc
);
1487 static int drm_queue_vblank_event(struct drm_device
*dev
, int pipe
,
1488 union drm_wait_vblank
*vblwait
,
1489 struct drm_file
*file_priv
)
1491 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1492 struct drm_pending_vblank_event
*e
;
1494 unsigned long flags
;
1498 e
= kzalloc(sizeof(*e
), GFP_KERNEL
);
1505 e
->base
.pid
= current
->pid
;
1506 e
->event
.base
.type
= DRM_EVENT_VBLANK
;
1507 e
->event
.base
.length
= sizeof(e
->event
);
1508 e
->event
.user_data
= vblwait
->request
.signal
;
1509 e
->base
.event
= &e
->event
.base
;
1510 e
->base
.file_priv
= file_priv
;
1511 e
->base
.destroy
= (void (*) (struct drm_pending_event
*)) kfree
;
1513 spin_lock_irqsave(&dev
->event_lock
, flags
);
1516 * drm_vblank_off() might have been called after we called
1517 * drm_vblank_get(). drm_vblank_off() holds event_lock
1518 * around the vblank disable, so no need for further locking.
1519 * The reference from drm_vblank_get() protects against
1520 * vblank disable from another source.
1522 if (!vblank
->enabled
) {
1527 if (file_priv
->event_space
< sizeof(e
->event
)) {
1532 file_priv
->event_space
-= sizeof(e
->event
);
1533 seq
= drm_vblank_count_and_time(dev
, pipe
, &now
);
1535 if ((vblwait
->request
.type
& _DRM_VBLANK_NEXTONMISS
) &&
1536 (seq
- vblwait
->request
.sequence
) <= (1 << 23)) {
1537 vblwait
->request
.sequence
= seq
+ 1;
1538 vblwait
->reply
.sequence
= vblwait
->request
.sequence
;
1541 DRM_DEBUG("event on vblank count %d, current %d, crtc %d\n",
1542 vblwait
->request
.sequence
, seq
, pipe
);
1544 trace_drm_vblank_event_queued(current
->pid
, pipe
,
1545 vblwait
->request
.sequence
);
1547 e
->event
.sequence
= vblwait
->request
.sequence
;
1548 if ((seq
- vblwait
->request
.sequence
) <= (1 << 23)) {
1549 drm_vblank_put(dev
, pipe
);
1550 send_vblank_event(dev
, e
, seq
, &now
);
1551 vblwait
->reply
.sequence
= seq
;
1553 /* drm_handle_vblank_events will call drm_vblank_put */
1554 list_add_tail(&e
->base
.link
, &dev
->vblank_event_list
);
1555 vblwait
->reply
.sequence
= vblwait
->request
.sequence
;
1558 spin_unlock_irqrestore(&dev
->event_lock
, flags
);
1563 spin_unlock_irqrestore(&dev
->event_lock
, flags
);
1566 drm_vblank_put(dev
, pipe
);
1573 * \param inode device inode.
1574 * \param file_priv DRM file private.
1575 * \param cmd command.
1576 * \param data user argument, pointing to a drm_wait_vblank structure.
1577 * \return zero on success or a negative number on failure.
1579 * This function enables the vblank interrupt on the pipe requested, then
1580 * sleeps waiting for the requested sequence number to occur, and drops
1581 * the vblank interrupt refcount afterwards. (vblank IRQ disable follows that
1582 * after a timeout with no further vblank waits scheduled).
1584 int drm_wait_vblank(struct drm_device
*dev
, void *data
,
1585 struct drm_file
*file_priv
)
1587 struct drm_vblank_crtc
*vblank
;
1588 union drm_wait_vblank
*vblwait
= data
;
1590 unsigned int flags
, seq
, crtc
, high_crtc
;
1592 if (!dev
->irq_enabled
)
1595 if (vblwait
->request
.type
& _DRM_VBLANK_SIGNAL
)
1598 if (vblwait
->request
.type
&
1599 ~(_DRM_VBLANK_TYPES_MASK
| _DRM_VBLANK_FLAGS_MASK
|
1600 _DRM_VBLANK_HIGH_CRTC_MASK
)) {
1601 DRM_ERROR("Unsupported type value 0x%x, supported mask 0x%x\n",
1602 vblwait
->request
.type
,
1603 (_DRM_VBLANK_TYPES_MASK
| _DRM_VBLANK_FLAGS_MASK
|
1604 _DRM_VBLANK_HIGH_CRTC_MASK
));
1608 flags
= vblwait
->request
.type
& _DRM_VBLANK_FLAGS_MASK
;
1609 high_crtc
= (vblwait
->request
.type
& _DRM_VBLANK_HIGH_CRTC_MASK
);
1611 crtc
= high_crtc
>> _DRM_VBLANK_HIGH_CRTC_SHIFT
;
1613 crtc
= flags
& _DRM_VBLANK_SECONDARY
? 1 : 0;
1614 if (crtc
>= dev
->num_crtcs
)
1617 vblank
= &dev
->vblank
[crtc
];
1619 ret
= drm_vblank_get(dev
, crtc
);
1621 DRM_DEBUG("failed to acquire vblank counter, %d\n", ret
);
1624 seq
= drm_vblank_count(dev
, crtc
);
1626 switch (vblwait
->request
.type
& _DRM_VBLANK_TYPES_MASK
) {
1627 case _DRM_VBLANK_RELATIVE
:
1628 vblwait
->request
.sequence
+= seq
;
1629 vblwait
->request
.type
&= ~_DRM_VBLANK_RELATIVE
;
1630 case _DRM_VBLANK_ABSOLUTE
:
1637 if (flags
& _DRM_VBLANK_EVENT
) {
1638 /* must hold on to the vblank ref until the event fires
1639 * drm_vblank_put will be called asynchronously
1641 return drm_queue_vblank_event(dev
, crtc
, vblwait
, file_priv
);
1644 if ((flags
& _DRM_VBLANK_NEXTONMISS
) &&
1645 (seq
- vblwait
->request
.sequence
) <= (1<<23)) {
1646 vblwait
->request
.sequence
= seq
+ 1;
1649 DRM_DEBUG("waiting on vblank count %d, crtc %d\n",
1650 vblwait
->request
.sequence
, crtc
);
1651 vblank
->last_wait
= vblwait
->request
.sequence
;
1652 DRM_WAIT_ON(ret
, vblank
->queue
, 3 * HZ
,
1653 (((drm_vblank_count(dev
, crtc
) -
1654 vblwait
->request
.sequence
) <= (1 << 23)) ||
1656 !dev
->irq_enabled
));
1658 if (ret
!= -EINTR
) {
1661 vblwait
->reply
.sequence
= drm_vblank_count_and_time(dev
, crtc
, &now
);
1662 vblwait
->reply
.tval_sec
= now
.tv_sec
;
1663 vblwait
->reply
.tval_usec
= now
.tv_usec
;
1665 DRM_DEBUG("returning %d to client\n",
1666 vblwait
->reply
.sequence
);
1668 DRM_DEBUG("vblank wait interrupted by signal\n");
1672 drm_vblank_put(dev
, crtc
);
1676 static void drm_handle_vblank_events(struct drm_device
*dev
, int crtc
)
1678 struct drm_pending_vblank_event
*e
, *t
;
1682 assert_spin_locked(&dev
->event_lock
);
1684 seq
= drm_vblank_count_and_time(dev
, crtc
, &now
);
1686 list_for_each_entry_safe(e
, t
, &dev
->vblank_event_list
, base
.link
) {
1687 if (e
->pipe
!= crtc
)
1689 if ((seq
- e
->event
.sequence
) > (1<<23))
1692 DRM_DEBUG("vblank event on %d, current %d\n",
1693 e
->event
.sequence
, seq
);
1695 list_del(&e
->base
.link
);
1696 drm_vblank_put(dev
, e
->pipe
);
1697 send_vblank_event(dev
, e
, seq
, &now
);
1700 trace_drm_vblank_event(crtc
, seq
);
1704 * drm_handle_vblank - handle a vblank event
1706 * @crtc: where this event occurred
1708 * Drivers should call this routine in their vblank interrupt handlers to
1709 * update the vblank counter and send any signals that may be pending.
1711 * This is the legacy version of drm_crtc_handle_vblank().
1713 bool drm_handle_vblank(struct drm_device
*dev
, int crtc
)
1715 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[crtc
];
1718 struct timeval tvblank
;
1719 unsigned long irqflags
;
1721 if (WARN_ON_ONCE(!dev
->num_crtcs
))
1724 if (WARN_ON(crtc
>= dev
->num_crtcs
))
1727 spin_lock_irqsave(&dev
->event_lock
, irqflags
);
1729 /* Need timestamp lock to prevent concurrent execution with
1730 * vblank enable/disable, as this would cause inconsistent
1731 * or corrupted timestamps and vblank counts.
1733 spin_lock(&dev
->vblank_time_lock
);
1735 /* Vblank irq handling disabled. Nothing to do. */
1736 if (!vblank
->enabled
) {
1737 spin_unlock(&dev
->vblank_time_lock
);
1738 spin_unlock_irqrestore(&dev
->event_lock
, irqflags
);
1742 /* Fetch corresponding timestamp for this vblank interval from
1743 * driver and store it in proper slot of timestamp ringbuffer.
1746 /* Get current timestamp and count. */
1747 vblcount
= vblank
->count
;
1748 drm_get_last_vbltimestamp(dev
, crtc
, &tvblank
, DRM_CALLED_FROM_VBLIRQ
);
1750 /* Compute time difference to timestamp of last vblank */
1751 diff_ns
= timeval_to_ns(&tvblank
) -
1752 timeval_to_ns(&vblanktimestamp(dev
, crtc
, vblcount
));
1754 /* Update vblank timestamp and count if at least
1755 * DRM_REDUNDANT_VBLIRQ_THRESH_NS nanoseconds
1756 * difference between last stored timestamp and current
1757 * timestamp. A smaller difference means basically
1758 * identical timestamps. Happens if this vblank has
1759 * been already processed and this is a redundant call,
1760 * e.g., due to spurious vblank interrupts. We need to
1761 * ignore those for accounting.
1763 if (abs64(diff_ns
) > DRM_REDUNDANT_VBLIRQ_THRESH_NS
)
1764 store_vblank(dev
, crtc
, 1, &tvblank
);
1766 DRM_DEBUG("crtc %d: Redundant vblirq ignored. diff_ns = %d\n",
1767 crtc
, (int) diff_ns
);
1769 spin_unlock(&dev
->vblank_time_lock
);
1771 wake_up(&vblank
->queue
);
1772 drm_handle_vblank_events(dev
, crtc
);
1774 spin_unlock_irqrestore(&dev
->event_lock
, irqflags
);
1778 EXPORT_SYMBOL(drm_handle_vblank
);
1781 * drm_crtc_handle_vblank - handle a vblank event
1782 * @crtc: where this event occurred
1784 * Drivers should call this routine in their vblank interrupt handlers to
1785 * update the vblank counter and send any signals that may be pending.
1787 * This is the native KMS version of drm_handle_vblank().
1790 * True if the event was successfully handled, false on failure.
1792 bool drm_crtc_handle_vblank(struct drm_crtc
*crtc
)
1794 return drm_handle_vblank(crtc
->dev
, drm_crtc_index(crtc
));
1796 EXPORT_SYMBOL(drm_crtc_handle_vblank
);