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_VBL("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_VBL("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, or we were called from the vblank interrupt.
236 * Otherwise reinitialize delayed at next vblank interrupt and assign 0
237 * for now, to mark the vblanktimestamp as invalid.
239 if (!rc
&& (flags
& DRM_CALLED_FROM_VBLIRQ
) == 0)
240 t_vblank
= (struct timeval
) {0, 0};
242 store_vblank(dev
, pipe
, diff
, &t_vblank
, cur_vblank
);
246 * Disable vblank irq's on crtc, make sure that last vblank count
247 * of hardware and corresponding consistent software vblank counter
248 * are preserved, even if there are any spurious vblank irq's after
251 static void vblank_disable_and_save(struct drm_device
*dev
, unsigned int pipe
)
253 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
254 unsigned long irqflags
;
256 /* Prevent vblank irq processing while disabling vblank irqs,
257 * so no updates of timestamps or count can happen after we've
258 * disabled. Needed to prevent races in case of delayed irq's.
260 spin_lock_irqsave(&dev
->vblank_time_lock
, irqflags
);
263 * Only disable vblank interrupts if they're enabled. This avoids
264 * calling the ->disable_vblank() operation in atomic context with the
265 * hardware potentially runtime suspended.
267 if (vblank
->enabled
) {
268 dev
->driver
->disable_vblank(dev
, pipe
);
269 vblank
->enabled
= false;
273 * Always update the count and timestamp to maintain the
274 * appearance that the counter has been ticking all along until
275 * this time. This makes the count account for the entire time
276 * between drm_vblank_on() and drm_vblank_off().
278 drm_update_vblank_count(dev
, pipe
, 0);
280 spin_unlock_irqrestore(&dev
->vblank_time_lock
, irqflags
);
283 static void vblank_disable_fn(unsigned long arg
)
285 struct drm_vblank_crtc
*vblank
= (void *)arg
;
286 struct drm_device
*dev
= vblank
->dev
;
287 unsigned int pipe
= vblank
->pipe
;
288 unsigned long irqflags
;
290 if (!dev
->vblank_disable_allowed
)
293 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
294 if (atomic_read(&vblank
->refcount
) == 0 && vblank
->enabled
) {
295 DRM_DEBUG("disabling vblank on crtc %u\n", pipe
);
296 vblank_disable_and_save(dev
, pipe
);
298 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
302 * drm_vblank_cleanup - cleanup vblank support
305 * This function cleans up any resources allocated in drm_vblank_init.
307 void drm_vblank_cleanup(struct drm_device
*dev
)
311 /* Bail if the driver didn't call drm_vblank_init() */
312 if (dev
->num_crtcs
== 0)
315 for (pipe
= 0; pipe
< dev
->num_crtcs
; pipe
++) {
316 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
318 WARN_ON(vblank
->enabled
&&
319 drm_core_check_feature(dev
, DRIVER_MODESET
));
321 del_timer_sync(&vblank
->disable_timer
);
328 EXPORT_SYMBOL(drm_vblank_cleanup
);
331 * drm_vblank_init - initialize vblank support
333 * @num_crtcs: number of CRTCs supported by @dev
335 * This function initializes vblank support for @num_crtcs display pipelines.
338 * Zero on success or a negative error code on failure.
340 int drm_vblank_init(struct drm_device
*dev
, unsigned int num_crtcs
)
345 spin_lock_init(&dev
->vbl_lock
);
346 spin_lock_init(&dev
->vblank_time_lock
);
348 dev
->num_crtcs
= num_crtcs
;
350 dev
->vblank
= kcalloc(num_crtcs
, sizeof(*dev
->vblank
), GFP_KERNEL
);
354 for (i
= 0; i
< num_crtcs
; i
++) {
355 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[i
];
359 init_waitqueue_head(&vblank
->queue
);
360 setup_timer(&vblank
->disable_timer
, vblank_disable_fn
,
361 (unsigned long)vblank
);
364 DRM_INFO("Supports vblank timestamp caching Rev 2 (21.10.2013).\n");
366 /* Driver specific high-precision vblank timestamping supported? */
367 if (dev
->driver
->get_vblank_timestamp
)
368 DRM_INFO("Driver supports precise vblank timestamp query.\n");
370 DRM_INFO("No driver support for vblank timestamp query.\n");
372 /* Must have precise timestamping for reliable vblank instant disable */
373 if (dev
->vblank_disable_immediate
&& !dev
->driver
->get_vblank_timestamp
) {
374 dev
->vblank_disable_immediate
= false;
375 DRM_INFO("Setting vblank_disable_immediate to false because "
376 "get_vblank_timestamp == NULL\n");
379 dev
->vblank_disable_allowed
= false;
387 EXPORT_SYMBOL(drm_vblank_init
);
389 static void drm_irq_vgaarb_nokms(void *cookie
, bool state
)
391 struct drm_device
*dev
= cookie
;
393 if (dev
->driver
->vgaarb_irq
) {
394 dev
->driver
->vgaarb_irq(dev
, state
);
398 if (!dev
->irq_enabled
)
402 if (dev
->driver
->irq_uninstall
)
403 dev
->driver
->irq_uninstall(dev
);
405 if (dev
->driver
->irq_preinstall
)
406 dev
->driver
->irq_preinstall(dev
);
407 if (dev
->driver
->irq_postinstall
)
408 dev
->driver
->irq_postinstall(dev
);
413 * drm_irq_install - install IRQ handler
415 * @irq: IRQ number to install the handler for
417 * Initializes the IRQ related data. Installs the handler, calling the driver
418 * irq_preinstall() and irq_postinstall() functions before and after the
421 * This is the simplified helper interface provided for drivers with no special
422 * needs. Drivers which need to install interrupt handlers for multiple
423 * interrupts must instead set drm_device->irq_enabled to signal the DRM core
424 * that vblank interrupts are available.
427 * Zero on success or a negative error code on failure.
429 int drm_irq_install(struct drm_device
*dev
, int irq
)
432 unsigned long sh_flags
= 0;
434 if (!drm_core_check_feature(dev
, DRIVER_HAVE_IRQ
))
440 /* Driver must have been initialized */
441 if (!dev
->dev_private
)
444 if (dev
->irq_enabled
)
446 dev
->irq_enabled
= true;
448 DRM_DEBUG("irq=%d\n", irq
);
450 /* Before installing handler */
451 if (dev
->driver
->irq_preinstall
)
452 dev
->driver
->irq_preinstall(dev
);
454 /* Install handler */
455 if (drm_core_check_feature(dev
, DRIVER_IRQ_SHARED
))
456 sh_flags
= IRQF_SHARED
;
458 ret
= request_irq(irq
, dev
->driver
->irq_handler
,
459 sh_flags
, dev
->driver
->name
, dev
);
462 dev
->irq_enabled
= false;
466 if (!drm_core_check_feature(dev
, DRIVER_MODESET
))
467 vga_client_register(dev
->pdev
, (void *)dev
, drm_irq_vgaarb_nokms
, NULL
);
469 /* After installing handler */
470 if (dev
->driver
->irq_postinstall
)
471 ret
= dev
->driver
->irq_postinstall(dev
);
474 dev
->irq_enabled
= false;
475 if (!drm_core_check_feature(dev
, DRIVER_MODESET
))
476 vga_client_register(dev
->pdev
, NULL
, NULL
, NULL
);
484 EXPORT_SYMBOL(drm_irq_install
);
487 * drm_irq_uninstall - uninstall the IRQ handler
490 * Calls the driver's irq_uninstall() function and unregisters the IRQ handler.
491 * This should only be called by drivers which used drm_irq_install() to set up
492 * their interrupt handler. Other drivers must only reset
493 * drm_device->irq_enabled to false.
495 * Note that for kernel modesetting drivers it is a bug if this function fails.
496 * The sanity checks are only to catch buggy user modesetting drivers which call
497 * the same function through an ioctl.
500 * Zero on success or a negative error code on failure.
502 int drm_irq_uninstall(struct drm_device
*dev
)
504 unsigned long irqflags
;
508 if (!drm_core_check_feature(dev
, DRIVER_HAVE_IRQ
))
511 irq_enabled
= dev
->irq_enabled
;
512 dev
->irq_enabled
= false;
515 * Wake up any waiters so they don't hang. This is just to paper over
516 * isssues for UMS drivers which aren't in full control of their
517 * vblank/irq handling. KMS drivers must ensure that vblanks are all
518 * disabled when uninstalling the irq handler.
520 if (dev
->num_crtcs
) {
521 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
522 for (i
= 0; i
< dev
->num_crtcs
; i
++) {
523 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[i
];
525 if (!vblank
->enabled
)
528 WARN_ON(drm_core_check_feature(dev
, DRIVER_MODESET
));
530 vblank_disable_and_save(dev
, i
);
531 wake_up(&vblank
->queue
);
533 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
539 DRM_DEBUG("irq=%d\n", dev
->irq
);
541 if (!drm_core_check_feature(dev
, DRIVER_MODESET
))
542 vga_client_register(dev
->pdev
, NULL
, NULL
, NULL
);
544 if (dev
->driver
->irq_uninstall
)
545 dev
->driver
->irq_uninstall(dev
);
547 free_irq(dev
->irq
, dev
);
551 EXPORT_SYMBOL(drm_irq_uninstall
);
556 * \param inode device inode.
557 * \param file_priv DRM file private.
558 * \param cmd command.
559 * \param arg user argument, pointing to a drm_control structure.
560 * \return zero on success or a negative number on failure.
562 * Calls irq_install() or irq_uninstall() according to \p arg.
564 int drm_control(struct drm_device
*dev
, void *data
,
565 struct drm_file
*file_priv
)
567 struct drm_control
*ctl
= data
;
570 /* if we haven't irq we fallback for compatibility reasons -
571 * this used to be a separate function in drm_dma.h
574 if (!drm_core_check_feature(dev
, DRIVER_HAVE_IRQ
))
576 if (drm_core_check_feature(dev
, DRIVER_MODESET
))
578 /* UMS was only ever support on pci devices. */
579 if (WARN_ON(!dev
->pdev
))
583 case DRM_INST_HANDLER
:
584 irq
= dev
->pdev
->irq
;
586 if (dev
->if_version
< DRM_IF_VERSION(1, 2) &&
589 mutex_lock(&dev
->struct_mutex
);
590 ret
= drm_irq_install(dev
, irq
);
591 mutex_unlock(&dev
->struct_mutex
);
594 case DRM_UNINST_HANDLER
:
595 mutex_lock(&dev
->struct_mutex
);
596 ret
= drm_irq_uninstall(dev
);
597 mutex_unlock(&dev
->struct_mutex
);
606 * drm_calc_timestamping_constants - calculate vblank timestamp constants
607 * @crtc: drm_crtc whose timestamp constants should be updated.
608 * @mode: display mode containing the scanout timings
610 * Calculate and store various constants which are later
611 * needed by vblank and swap-completion timestamping, e.g,
612 * by drm_calc_vbltimestamp_from_scanoutpos(). They are
613 * derived from CRTC's true scanout timing, so they take
614 * things like panel scaling or other adjustments into account.
616 void drm_calc_timestamping_constants(struct drm_crtc
*crtc
,
617 const struct drm_display_mode
*mode
)
619 struct drm_vblank_crtc
*vblank
= &crtc
->dev
->vblank
[drm_crtc_index(crtc
)];
620 int linedur_ns
= 0, framedur_ns
= 0;
621 int dotclock
= mode
->crtc_clock
;
623 /* Valid dotclock? */
625 int frame_size
= mode
->crtc_htotal
* mode
->crtc_vtotal
;
628 * Convert scanline length in pixels and video
629 * dot clock to line duration and frame duration
632 linedur_ns
= div_u64((u64
) mode
->crtc_htotal
* 1000000, dotclock
);
633 framedur_ns
= div_u64((u64
) frame_size
* 1000000, dotclock
);
636 * Fields of interlaced scanout modes are only half a frame duration.
638 if (mode
->flags
& DRM_MODE_FLAG_INTERLACE
)
641 DRM_ERROR("crtc %u: Can't calculate constants, dotclock = 0!\n",
644 vblank
->linedur_ns
= linedur_ns
;
645 vblank
->framedur_ns
= framedur_ns
;
647 DRM_DEBUG("crtc %u: hwmode: htotal %d, vtotal %d, vdisplay %d\n",
648 crtc
->base
.id
, mode
->crtc_htotal
,
649 mode
->crtc_vtotal
, mode
->crtc_vdisplay
);
650 DRM_DEBUG("crtc %u: clock %d kHz framedur %d linedur %d\n",
651 crtc
->base
.id
, dotclock
, framedur_ns
, linedur_ns
);
653 EXPORT_SYMBOL(drm_calc_timestamping_constants
);
656 * drm_calc_vbltimestamp_from_scanoutpos - precise vblank timestamp helper
658 * @pipe: index of CRTC whose vblank timestamp to retrieve
659 * @max_error: Desired maximum allowable error in timestamps (nanosecs)
660 * On return contains true maximum error of timestamp
661 * @vblank_time: Pointer to struct timeval which should receive the timestamp
662 * @flags: Flags to pass to driver:
664 * DRM_CALLED_FROM_VBLIRQ = If function is called from vbl IRQ handler
665 * @mode: mode which defines the scanout timings
667 * Implements calculation of exact vblank timestamps from given drm_display_mode
668 * timings and current video scanout position of a CRTC. This can be called from
669 * within get_vblank_timestamp() implementation of a kms driver to implement the
670 * actual timestamping.
672 * Should return timestamps conforming to the OML_sync_control OpenML
673 * extension specification. The timestamp corresponds to the end of
674 * the vblank interval, aka start of scanout of topmost-leftmost display
675 * pixel in the following video frame.
677 * Requires support for optional dev->driver->get_scanout_position()
678 * in kms driver, plus a bit of setup code to provide a drm_display_mode
679 * that corresponds to the true scanout timing.
681 * The current implementation only handles standard video modes. It
682 * returns as no operation if a doublescan or interlaced video mode is
683 * active. Higher level code is expected to handle this.
686 * Negative value on error, failure or if not supported in current
689 * -EINVAL - Invalid CRTC.
690 * -EAGAIN - Temporary unavailable, e.g., called before initial modeset.
691 * -ENOTSUPP - Function not supported in current display mode.
692 * -EIO - Failed, e.g., due to failed scanout position query.
694 * Returns or'ed positive status flags on success:
696 * DRM_VBLANKTIME_SCANOUTPOS_METHOD - Signal this method used for timestamping.
697 * DRM_VBLANKTIME_INVBL - Timestamp taken while scanout was in vblank interval.
700 int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device
*dev
,
703 struct timeval
*vblank_time
,
705 const struct drm_display_mode
*mode
)
707 struct timeval tv_etime
;
708 ktime_t stime
, etime
;
709 unsigned int vbl_status
;
710 int ret
= DRM_VBLANKTIME_SCANOUTPOS_METHOD
;
712 int delta_ns
, duration_ns
;
714 if (pipe
>= dev
->num_crtcs
) {
715 DRM_ERROR("Invalid crtc %u\n", pipe
);
719 /* Scanout position query not supported? Should not happen. */
720 if (!dev
->driver
->get_scanout_position
) {
721 DRM_ERROR("Called from driver w/o get_scanout_position()!?\n");
725 /* If mode timing undefined, just return as no-op:
726 * Happens during initial modesetting of a crtc.
728 if (mode
->crtc_clock
== 0) {
729 DRM_DEBUG("crtc %u: Noop due to uninitialized mode.\n", pipe
);
733 /* Get current scanout position with system timestamp.
734 * Repeat query up to DRM_TIMESTAMP_MAXRETRIES times
735 * if single query takes longer than max_error nanoseconds.
737 * This guarantees a tight bound on maximum error if
738 * code gets preempted or delayed for some reason.
740 for (i
= 0; i
< DRM_TIMESTAMP_MAXRETRIES
; i
++) {
742 * Get vertical and horizontal scanout position vpos, hpos,
743 * and bounding timestamps stime, etime, pre/post query.
745 vbl_status
= dev
->driver
->get_scanout_position(dev
, pipe
, flags
,
750 /* Return as no-op if scanout query unsupported or failed. */
751 if (!(vbl_status
& DRM_SCANOUTPOS_VALID
)) {
752 DRM_DEBUG("crtc %u : scanoutpos query failed [0x%x].\n",
757 /* Compute uncertainty in timestamp of scanout position query. */
758 duration_ns
= ktime_to_ns(etime
) - ktime_to_ns(stime
);
760 /* Accept result with < max_error nsecs timing uncertainty. */
761 if (duration_ns
<= *max_error
)
765 /* Noisy system timing? */
766 if (i
== DRM_TIMESTAMP_MAXRETRIES
) {
767 DRM_DEBUG("crtc %u: Noisy timestamp %d us > %d us [%d reps].\n",
768 pipe
, duration_ns
/1000, *max_error
/1000, i
);
771 /* Return upper bound of timestamp precision error. */
772 *max_error
= duration_ns
;
774 /* Check if in vblank area:
775 * vpos is >=0 in video scanout area, but negative
776 * within vblank area, counting down the number of lines until
779 if (vbl_status
& DRM_SCANOUTPOS_IN_VBLANK
)
780 ret
|= DRM_VBLANKTIME_IN_VBLANK
;
782 /* Convert scanout position into elapsed time at raw_time query
783 * since start of scanout at first display scanline. delta_ns
784 * can be negative if start of scanout hasn't happened yet.
786 delta_ns
= div_s64(1000000LL * (vpos
* mode
->crtc_htotal
+ hpos
),
789 if (!drm_timestamp_monotonic
)
790 etime
= ktime_mono_to_real(etime
);
792 /* save this only for debugging purposes */
793 tv_etime
= ktime_to_timeval(etime
);
794 /* Subtract time delta from raw timestamp to get final
795 * vblank_time timestamp for end of vblank.
798 etime
= ktime_add_ns(etime
, -delta_ns
);
800 etime
= ktime_sub_ns(etime
, delta_ns
);
801 *vblank_time
= ktime_to_timeval(etime
);
803 DRM_DEBUG_VBL("crtc %u : v 0x%x p(%d,%d)@ %ld.%ld -> %ld.%ld [e %d us, %d rep]\n",
804 pipe
, vbl_status
, hpos
, vpos
,
805 (long)tv_etime
.tv_sec
, (long)tv_etime
.tv_usec
,
806 (long)vblank_time
->tv_sec
, (long)vblank_time
->tv_usec
,
807 duration_ns
/1000, i
);
811 EXPORT_SYMBOL(drm_calc_vbltimestamp_from_scanoutpos
);
813 static struct timeval
get_drm_timestamp(void)
817 now
= drm_timestamp_monotonic
? ktime_get() : ktime_get_real();
818 return ktime_to_timeval(now
);
822 * drm_get_last_vbltimestamp - retrieve raw timestamp for the most recent
825 * @pipe: index of CRTC whose vblank timestamp to retrieve
826 * @tvblank: Pointer to target struct timeval which should receive the timestamp
827 * @flags: Flags to pass to driver:
829 * DRM_CALLED_FROM_VBLIRQ = If function is called from vbl IRQ handler
831 * Fetches the system timestamp corresponding to the time of the most recent
832 * vblank interval on specified CRTC. May call into kms-driver to
833 * compute the timestamp with a high-precision GPU specific method.
835 * Returns zero if timestamp originates from uncorrected do_gettimeofday()
836 * call, i.e., it isn't very precisely locked to the true vblank.
839 * True if timestamp is considered to be very precise, false otherwise.
842 drm_get_last_vbltimestamp(struct drm_device
*dev
, unsigned int pipe
,
843 struct timeval
*tvblank
, unsigned flags
)
847 /* Define requested maximum error on timestamps (nanoseconds). */
848 int max_error
= (int) drm_timestamp_precision
* 1000;
850 /* Query driver if possible and precision timestamping enabled. */
851 if (dev
->driver
->get_vblank_timestamp
&& (max_error
> 0)) {
852 ret
= dev
->driver
->get_vblank_timestamp(dev
, pipe
, &max_error
,
858 /* GPU high precision timestamp query unsupported or failed.
859 * Return current monotonic/gettimeofday timestamp as best estimate.
861 *tvblank
= get_drm_timestamp();
867 * drm_vblank_count - retrieve "cooked" vblank counter value
869 * @pipe: index of CRTC for which to retrieve the counter
871 * Fetches the "cooked" vblank count value that represents the number of
872 * vblank events since the system was booted, including lost events due to
873 * modesetting activity.
875 * This is the legacy version of drm_crtc_vblank_count().
878 * The software vblank counter.
880 u32
drm_vblank_count(struct drm_device
*dev
, unsigned int pipe
)
882 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
884 if (WARN_ON(pipe
>= dev
->num_crtcs
))
887 return vblank
->count
;
889 EXPORT_SYMBOL(drm_vblank_count
);
892 * drm_crtc_vblank_count - retrieve "cooked" vblank counter value
893 * @crtc: which counter to retrieve
895 * Fetches the "cooked" vblank count value that represents the number of
896 * vblank events since the system was booted, including lost events due to
897 * modesetting activity.
899 * This is the native KMS version of drm_vblank_count().
902 * The software vblank counter.
904 u32
drm_crtc_vblank_count(struct drm_crtc
*crtc
)
906 return drm_vblank_count(crtc
->dev
, drm_crtc_index(crtc
));
908 EXPORT_SYMBOL(drm_crtc_vblank_count
);
911 * drm_vblank_count_and_time - retrieve "cooked" vblank counter value and the
912 * system timestamp corresponding to that vblank counter value.
914 * @pipe: index of CRTC whose counter to retrieve
915 * @vblanktime: Pointer to struct timeval to receive the vblank timestamp.
917 * Fetches the "cooked" vblank count value that represents the number of
918 * vblank events since the system was booted, including lost events due to
919 * modesetting activity. Returns corresponding system timestamp of the time
920 * of the vblank interval that corresponds to the current vblank counter value.
922 * This is the legacy version of drm_crtc_vblank_count_and_time().
924 u32
drm_vblank_count_and_time(struct drm_device
*dev
, unsigned int pipe
,
925 struct timeval
*vblanktime
)
927 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
928 int count
= DRM_TIMESTAMP_MAXRETRIES
;
931 if (WARN_ON(pipe
>= dev
->num_crtcs
))
935 * Vblank timestamps are read lockless. To ensure consistency the vblank
936 * counter is rechecked and ordering is ensured using memory barriers.
937 * This works like a seqlock. The write-side barriers are in store_vblank.
940 cur_vblank
= vblank
->count
;
942 *vblanktime
= vblanktimestamp(dev
, pipe
, cur_vblank
);
944 } while (cur_vblank
!= vblank
->count
&& --count
> 0);
948 EXPORT_SYMBOL(drm_vblank_count_and_time
);
951 * drm_crtc_vblank_count_and_time - retrieve "cooked" vblank counter value
952 * and the system timestamp corresponding to that vblank counter value
953 * @crtc: which counter to retrieve
954 * @vblanktime: Pointer to struct timeval to receive the vblank timestamp.
956 * Fetches the "cooked" vblank count value that represents the number of
957 * vblank events since the system was booted, including lost events due to
958 * modesetting activity. Returns corresponding system timestamp of the time
959 * of the vblank interval that corresponds to the current vblank counter value.
961 * This is the native KMS version of drm_vblank_count_and_time().
963 u32
drm_crtc_vblank_count_and_time(struct drm_crtc
*crtc
,
964 struct timeval
*vblanktime
)
966 return drm_vblank_count_and_time(crtc
->dev
, drm_crtc_index(crtc
),
969 EXPORT_SYMBOL(drm_crtc_vblank_count_and_time
);
971 static void send_vblank_event(struct drm_device
*dev
,
972 struct drm_pending_vblank_event
*e
,
973 unsigned long seq
, struct timeval
*now
)
975 WARN_ON_SMP(!spin_is_locked(&dev
->event_lock
));
976 e
->event
.sequence
= seq
;
977 e
->event
.tv_sec
= now
->tv_sec
;
978 e
->event
.tv_usec
= now
->tv_usec
;
980 list_add_tail(&e
->base
.link
,
981 &e
->base
.file_priv
->event_list
);
982 wake_up_interruptible(&e
->base
.file_priv
->event_wait
);
983 trace_drm_vblank_event_delivered(e
->base
.pid
, e
->pipe
,
988 * drm_send_vblank_event - helper to send vblank event after pageflip
991 * @e: the event to send
993 * Updates sequence # and timestamp on event, and sends it to userspace.
994 * Caller must hold event lock.
996 * This is the legacy version of drm_crtc_send_vblank_event().
998 void drm_send_vblank_event(struct drm_device
*dev
, unsigned int pipe
,
999 struct drm_pending_vblank_event
*e
)
1004 if (dev
->num_crtcs
> 0) {
1005 seq
= drm_vblank_count_and_time(dev
, pipe
, &now
);
1009 now
= get_drm_timestamp();
1012 send_vblank_event(dev
, e
, seq
, &now
);
1014 EXPORT_SYMBOL(drm_send_vblank_event
);
1017 * drm_crtc_send_vblank_event - helper to send vblank event after pageflip
1018 * @crtc: the source CRTC of the vblank event
1019 * @e: the event to send
1021 * Updates sequence # and timestamp on event, and sends it to userspace.
1022 * Caller must hold event lock.
1024 * This is the native KMS version of drm_send_vblank_event().
1026 void drm_crtc_send_vblank_event(struct drm_crtc
*crtc
,
1027 struct drm_pending_vblank_event
*e
)
1029 drm_send_vblank_event(crtc
->dev
, drm_crtc_index(crtc
), e
);
1031 EXPORT_SYMBOL(drm_crtc_send_vblank_event
);
1034 * drm_vblank_enable - enable the vblank interrupt on a CRTC
1039 * Zero on success or a negative error code on failure.
1041 static int drm_vblank_enable(struct drm_device
*dev
, unsigned int pipe
)
1043 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1046 assert_spin_locked(&dev
->vbl_lock
);
1048 spin_lock(&dev
->vblank_time_lock
);
1050 if (!vblank
->enabled
) {
1052 * Enable vblank irqs under vblank_time_lock protection.
1053 * All vblank count & timestamp updates are held off
1054 * until we are done reinitializing master counter and
1055 * timestamps. Filtercode in drm_handle_vblank() will
1056 * prevent double-accounting of same vblank interval.
1058 ret
= dev
->driver
->enable_vblank(dev
, pipe
);
1059 DRM_DEBUG("enabling vblank on crtc %u, ret: %d\n", pipe
, ret
);
1061 atomic_dec(&vblank
->refcount
);
1063 vblank
->enabled
= true;
1064 drm_update_vblank_count(dev
, pipe
, 0);
1068 spin_unlock(&dev
->vblank_time_lock
);
1074 * drm_vblank_get - get a reference count on vblank events
1076 * @pipe: index of CRTC to own
1078 * Acquire a reference count on vblank events to avoid having them disabled
1081 * This is the legacy version of drm_crtc_vblank_get().
1084 * Zero on success or a negative error code on failure.
1086 int drm_vblank_get(struct drm_device
*dev
, unsigned int pipe
)
1088 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1089 unsigned long irqflags
;
1092 if (!dev
->num_crtcs
)
1095 if (WARN_ON(pipe
>= dev
->num_crtcs
))
1098 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
1099 /* Going from 0->1 means we have to enable interrupts again */
1100 if (atomic_add_return(1, &vblank
->refcount
) == 1) {
1101 ret
= drm_vblank_enable(dev
, pipe
);
1103 if (!vblank
->enabled
) {
1104 atomic_dec(&vblank
->refcount
);
1108 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
1112 EXPORT_SYMBOL(drm_vblank_get
);
1115 * drm_crtc_vblank_get - get a reference count on vblank events
1116 * @crtc: which CRTC to own
1118 * Acquire a reference count on vblank events to avoid having them disabled
1121 * This is the native kms version of drm_vblank_get().
1124 * Zero on success or a negative error code on failure.
1126 int drm_crtc_vblank_get(struct drm_crtc
*crtc
)
1128 return drm_vblank_get(crtc
->dev
, drm_crtc_index(crtc
));
1130 EXPORT_SYMBOL(drm_crtc_vblank_get
);
1133 * drm_vblank_put - release ownership of vblank events
1135 * @pipe: index of CRTC to release
1137 * Release ownership of a given vblank counter, turning off interrupts
1138 * if possible. Disable interrupts after drm_vblank_offdelay milliseconds.
1140 * This is the legacy version of drm_crtc_vblank_put().
1142 void drm_vblank_put(struct drm_device
*dev
, unsigned int pipe
)
1144 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1146 if (WARN_ON(pipe
>= dev
->num_crtcs
))
1149 if (WARN_ON(atomic_read(&vblank
->refcount
) == 0))
1152 /* Last user schedules interrupt disable */
1153 if (atomic_dec_and_test(&vblank
->refcount
)) {
1154 if (drm_vblank_offdelay
== 0)
1156 else if (dev
->vblank_disable_immediate
|| drm_vblank_offdelay
< 0)
1157 vblank_disable_fn((unsigned long)vblank
);
1159 mod_timer(&vblank
->disable_timer
,
1160 jiffies
+ ((drm_vblank_offdelay
* HZ
)/1000));
1163 EXPORT_SYMBOL(drm_vblank_put
);
1166 * drm_crtc_vblank_put - give up ownership of vblank events
1167 * @crtc: which counter to give up
1169 * Release ownership of a given vblank counter, turning off interrupts
1170 * if possible. Disable interrupts after drm_vblank_offdelay milliseconds.
1172 * This is the native kms version of drm_vblank_put().
1174 void drm_crtc_vblank_put(struct drm_crtc
*crtc
)
1176 drm_vblank_put(crtc
->dev
, drm_crtc_index(crtc
));
1178 EXPORT_SYMBOL(drm_crtc_vblank_put
);
1181 * drm_wait_one_vblank - wait for one vblank
1185 * This waits for one vblank to pass on @pipe, using the irq driver interfaces.
1186 * It is a failure to call this when the vblank irq for @pipe is disabled, e.g.
1187 * due to lack of driver support or because the crtc is off.
1189 void drm_wait_one_vblank(struct drm_device
*dev
, unsigned int pipe
)
1191 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1195 if (WARN_ON(pipe
>= dev
->num_crtcs
))
1198 ret
= drm_vblank_get(dev
, pipe
);
1199 if (WARN(ret
, "vblank not available on crtc %i, ret=%i\n", pipe
, ret
))
1202 last
= drm_vblank_count(dev
, pipe
);
1204 ret
= wait_event_timeout(vblank
->queue
,
1205 last
!= drm_vblank_count(dev
, pipe
),
1206 msecs_to_jiffies(100));
1208 WARN(ret
== 0, "vblank wait timed out on crtc %i\n", pipe
);
1210 drm_vblank_put(dev
, pipe
);
1212 EXPORT_SYMBOL(drm_wait_one_vblank
);
1215 * drm_crtc_wait_one_vblank - wait for one vblank
1218 * This waits for one vblank to pass on @crtc, using the irq driver interfaces.
1219 * It is a failure to call this when the vblank irq for @crtc is disabled, e.g.
1220 * due to lack of driver support or because the crtc is off.
1222 void drm_crtc_wait_one_vblank(struct drm_crtc
*crtc
)
1224 drm_wait_one_vblank(crtc
->dev
, drm_crtc_index(crtc
));
1226 EXPORT_SYMBOL(drm_crtc_wait_one_vblank
);
1229 * drm_vblank_off - disable vblank events on a CRTC
1233 * Drivers can use this function to shut down the vblank interrupt handling when
1234 * disabling a crtc. This function ensures that the latest vblank frame count is
1235 * stored so that drm_vblank_on() can restore it again.
1237 * Drivers must use this function when the hardware vblank counter can get
1238 * reset, e.g. when suspending.
1240 * This is the legacy version of drm_crtc_vblank_off().
1242 void drm_vblank_off(struct drm_device
*dev
, unsigned int pipe
)
1244 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1245 struct drm_pending_vblank_event
*e
, *t
;
1247 unsigned long irqflags
;
1250 if (WARN_ON(pipe
>= dev
->num_crtcs
))
1253 spin_lock_irqsave(&dev
->event_lock
, irqflags
);
1255 spin_lock(&dev
->vbl_lock
);
1256 vblank_disable_and_save(dev
, pipe
);
1257 wake_up(&vblank
->queue
);
1260 * Prevent subsequent drm_vblank_get() from re-enabling
1261 * the vblank interrupt by bumping the refcount.
1263 if (!vblank
->inmodeset
) {
1264 atomic_inc(&vblank
->refcount
);
1265 vblank
->inmodeset
= 1;
1267 spin_unlock(&dev
->vbl_lock
);
1269 /* Send any queued vblank events, lest the natives grow disquiet */
1270 seq
= drm_vblank_count_and_time(dev
, pipe
, &now
);
1272 list_for_each_entry_safe(e
, t
, &dev
->vblank_event_list
, base
.link
) {
1273 if (e
->pipe
!= pipe
)
1275 DRM_DEBUG("Sending premature vblank event on disable: "
1276 "wanted %d, current %d\n",
1277 e
->event
.sequence
, seq
);
1278 list_del(&e
->base
.link
);
1279 drm_vblank_put(dev
, pipe
);
1280 send_vblank_event(dev
, e
, seq
, &now
);
1282 spin_unlock_irqrestore(&dev
->event_lock
, irqflags
);
1284 EXPORT_SYMBOL(drm_vblank_off
);
1287 * drm_crtc_vblank_off - disable vblank events on a CRTC
1288 * @crtc: CRTC in question
1290 * Drivers can use this function to shut down the vblank interrupt handling when
1291 * disabling a crtc. This function ensures that the latest vblank frame count is
1292 * stored so that drm_vblank_on can restore it again.
1294 * Drivers must use this function when the hardware vblank counter can get
1295 * reset, e.g. when suspending.
1297 * This is the native kms version of drm_vblank_off().
1299 void drm_crtc_vblank_off(struct drm_crtc
*crtc
)
1301 drm_vblank_off(crtc
->dev
, drm_crtc_index(crtc
));
1303 EXPORT_SYMBOL(drm_crtc_vblank_off
);
1306 * drm_crtc_vblank_reset - reset vblank state to off on a CRTC
1307 * @crtc: CRTC in question
1309 * Drivers can use this function to reset the vblank state to off at load time.
1310 * Drivers should use this together with the drm_crtc_vblank_off() and
1311 * drm_crtc_vblank_on() functions. The difference compared to
1312 * drm_crtc_vblank_off() is that this function doesn't save the vblank counter
1313 * and hence doesn't need to call any driver hooks.
1315 void drm_crtc_vblank_reset(struct drm_crtc
*crtc
)
1317 struct drm_device
*dev
= crtc
->dev
;
1318 unsigned long irqflags
;
1319 unsigned int pipe
= drm_crtc_index(crtc
);
1320 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1322 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
1324 * Prevent subsequent drm_vblank_get() from enabling the vblank
1325 * interrupt by bumping the refcount.
1327 if (!vblank
->inmodeset
) {
1328 atomic_inc(&vblank
->refcount
);
1329 vblank
->inmodeset
= 1;
1331 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
1333 WARN_ON(!list_empty(&dev
->vblank_event_list
));
1335 EXPORT_SYMBOL(drm_crtc_vblank_reset
);
1338 * drm_vblank_on - enable vblank events on a CRTC
1342 * This functions restores the vblank interrupt state captured with
1343 * drm_vblank_off() again. Note that calls to drm_vblank_on() and
1344 * drm_vblank_off() can be unbalanced and so can also be unconditionally called
1345 * in driver load code to reflect the current hardware state of the crtc.
1347 * This is the legacy version of drm_crtc_vblank_on().
1349 void drm_vblank_on(struct drm_device
*dev
, unsigned int pipe
)
1351 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1352 unsigned long irqflags
;
1354 if (WARN_ON(pipe
>= dev
->num_crtcs
))
1357 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
1358 /* Drop our private "prevent drm_vblank_get" refcount */
1359 if (vblank
->inmodeset
) {
1360 atomic_dec(&vblank
->refcount
);
1361 vblank
->inmodeset
= 0;
1364 drm_reset_vblank_timestamp(dev
, pipe
);
1367 * re-enable interrupts if there are users left, or the
1368 * user wishes vblank interrupts to be enabled all the time.
1370 if (atomic_read(&vblank
->refcount
) != 0 ||
1371 (!dev
->vblank_disable_immediate
&& drm_vblank_offdelay
== 0))
1372 WARN_ON(drm_vblank_enable(dev
, pipe
));
1373 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
1375 EXPORT_SYMBOL(drm_vblank_on
);
1378 * drm_crtc_vblank_on - enable vblank events on a CRTC
1379 * @crtc: CRTC in question
1381 * This functions restores the vblank interrupt state captured with
1382 * drm_vblank_off() again. Note that calls to drm_vblank_on() and
1383 * drm_vblank_off() can be unbalanced and so can also be unconditionally called
1384 * in driver load code to reflect the current hardware state of the crtc.
1386 * This is the native kms version of drm_vblank_on().
1388 void drm_crtc_vblank_on(struct drm_crtc
*crtc
)
1390 drm_vblank_on(crtc
->dev
, drm_crtc_index(crtc
));
1392 EXPORT_SYMBOL(drm_crtc_vblank_on
);
1395 * drm_vblank_pre_modeset - account for vblanks across mode sets
1399 * Account for vblank events across mode setting events, which will likely
1400 * reset the hardware frame counter.
1402 * This is done by grabbing a temporary vblank reference to ensure that the
1403 * vblank interrupt keeps running across the modeset sequence. With this the
1404 * software-side vblank frame counting will ensure that there are no jumps or
1407 * Unfortunately this approach is racy and also doesn't work when the vblank
1408 * interrupt stops running, e.g. across system suspend resume. It is therefore
1409 * highly recommended that drivers use the newer drm_vblank_off() and
1410 * drm_vblank_on() instead. drm_vblank_pre_modeset() only works correctly when
1411 * using "cooked" software vblank frame counters and not relying on any hardware
1414 * Drivers must call drm_vblank_post_modeset() when re-enabling the same crtc
1417 void drm_vblank_pre_modeset(struct drm_device
*dev
, unsigned int pipe
)
1419 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1421 /* vblank is not initialized (IRQ not installed ?), or has been freed */
1422 if (!dev
->num_crtcs
)
1425 if (WARN_ON(pipe
>= dev
->num_crtcs
))
1429 * To avoid all the problems that might happen if interrupts
1430 * were enabled/disabled around or between these calls, we just
1431 * have the kernel take a reference on the CRTC (just once though
1432 * to avoid corrupting the count if multiple, mismatch calls occur),
1433 * so that interrupts remain enabled in the interim.
1435 if (!vblank
->inmodeset
) {
1436 vblank
->inmodeset
= 0x1;
1437 if (drm_vblank_get(dev
, pipe
) == 0)
1438 vblank
->inmodeset
|= 0x2;
1441 EXPORT_SYMBOL(drm_vblank_pre_modeset
);
1444 * drm_vblank_post_modeset - undo drm_vblank_pre_modeset changes
1448 * This function again drops the temporary vblank reference acquired in
1449 * drm_vblank_pre_modeset.
1451 void drm_vblank_post_modeset(struct drm_device
*dev
, unsigned int pipe
)
1453 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1454 unsigned long irqflags
;
1456 /* vblank is not initialized (IRQ not installed ?), or has been freed */
1457 if (!dev
->num_crtcs
)
1460 if (WARN_ON(pipe
>= dev
->num_crtcs
))
1463 if (vblank
->inmodeset
) {
1464 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
1465 dev
->vblank_disable_allowed
= true;
1466 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
1468 if (vblank
->inmodeset
& 0x2)
1469 drm_vblank_put(dev
, pipe
);
1471 vblank
->inmodeset
= 0;
1474 EXPORT_SYMBOL(drm_vblank_post_modeset
);
1477 * drm_modeset_ctl - handle vblank event counter changes across mode switch
1478 * @DRM_IOCTL_ARGS: standard ioctl arguments
1480 * Applications should call the %_DRM_PRE_MODESET and %_DRM_POST_MODESET
1481 * ioctls around modesetting so that any lost vblank events are accounted for.
1483 * Generally the counter will reset across mode sets. If interrupts are
1484 * enabled around this call, we don't have to do anything since the counter
1485 * will have already been incremented.
1487 int drm_modeset_ctl(struct drm_device
*dev
, void *data
,
1488 struct drm_file
*file_priv
)
1490 struct drm_modeset_ctl
*modeset
= data
;
1493 /* If drm_vblank_init() hasn't been called yet, just no-op */
1494 if (!dev
->num_crtcs
)
1497 /* KMS drivers handle this internally */
1498 if (drm_core_check_feature(dev
, DRIVER_MODESET
))
1501 pipe
= modeset
->crtc
;
1502 if (pipe
>= dev
->num_crtcs
)
1505 switch (modeset
->cmd
) {
1506 case _DRM_PRE_MODESET
:
1507 drm_vblank_pre_modeset(dev
, pipe
);
1509 case _DRM_POST_MODESET
:
1510 drm_vblank_post_modeset(dev
, pipe
);
1519 static int drm_queue_vblank_event(struct drm_device
*dev
, unsigned int pipe
,
1520 union drm_wait_vblank
*vblwait
,
1521 struct drm_file
*file_priv
)
1523 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1524 struct drm_pending_vblank_event
*e
;
1526 unsigned long flags
;
1530 e
= kzalloc(sizeof(*e
), GFP_KERNEL
);
1537 e
->base
.pid
= current
->pid
;
1538 e
->event
.base
.type
= DRM_EVENT_VBLANK
;
1539 e
->event
.base
.length
= sizeof(e
->event
);
1540 e
->event
.user_data
= vblwait
->request
.signal
;
1541 e
->base
.event
= &e
->event
.base
;
1542 e
->base
.file_priv
= file_priv
;
1543 e
->base
.destroy
= (void (*) (struct drm_pending_event
*)) kfree
;
1545 spin_lock_irqsave(&dev
->event_lock
, flags
);
1548 * drm_vblank_off() might have been called after we called
1549 * drm_vblank_get(). drm_vblank_off() holds event_lock
1550 * around the vblank disable, so no need for further locking.
1551 * The reference from drm_vblank_get() protects against
1552 * vblank disable from another source.
1554 if (!vblank
->enabled
) {
1559 if (file_priv
->event_space
< sizeof(e
->event
)) {
1564 file_priv
->event_space
-= sizeof(e
->event
);
1565 seq
= drm_vblank_count_and_time(dev
, pipe
, &now
);
1567 if ((vblwait
->request
.type
& _DRM_VBLANK_NEXTONMISS
) &&
1568 (seq
- vblwait
->request
.sequence
) <= (1 << 23)) {
1569 vblwait
->request
.sequence
= seq
+ 1;
1570 vblwait
->reply
.sequence
= vblwait
->request
.sequence
;
1573 DRM_DEBUG("event on vblank count %d, current %d, crtc %u\n",
1574 vblwait
->request
.sequence
, seq
, pipe
);
1576 trace_drm_vblank_event_queued(current
->pid
, pipe
,
1577 vblwait
->request
.sequence
);
1579 e
->event
.sequence
= vblwait
->request
.sequence
;
1580 if ((seq
- vblwait
->request
.sequence
) <= (1 << 23)) {
1581 drm_vblank_put(dev
, pipe
);
1582 send_vblank_event(dev
, e
, seq
, &now
);
1583 vblwait
->reply
.sequence
= seq
;
1585 /* drm_handle_vblank_events will call drm_vblank_put */
1586 list_add_tail(&e
->base
.link
, &dev
->vblank_event_list
);
1587 vblwait
->reply
.sequence
= vblwait
->request
.sequence
;
1590 spin_unlock_irqrestore(&dev
->event_lock
, flags
);
1595 spin_unlock_irqrestore(&dev
->event_lock
, flags
);
1598 drm_vblank_put(dev
, pipe
);
1605 * \param inode device inode.
1606 * \param file_priv DRM file private.
1607 * \param cmd command.
1608 * \param data user argument, pointing to a drm_wait_vblank structure.
1609 * \return zero on success or a negative number on failure.
1611 * This function enables the vblank interrupt on the pipe requested, then
1612 * sleeps waiting for the requested sequence number to occur, and drops
1613 * the vblank interrupt refcount afterwards. (vblank IRQ disable follows that
1614 * after a timeout with no further vblank waits scheduled).
1616 int drm_wait_vblank(struct drm_device
*dev
, void *data
,
1617 struct drm_file
*file_priv
)
1619 struct drm_vblank_crtc
*vblank
;
1620 union drm_wait_vblank
*vblwait
= data
;
1622 unsigned int flags
, seq
, pipe
, high_pipe
;
1624 if (!dev
->irq_enabled
)
1627 if (vblwait
->request
.type
& _DRM_VBLANK_SIGNAL
)
1630 if (vblwait
->request
.type
&
1631 ~(_DRM_VBLANK_TYPES_MASK
| _DRM_VBLANK_FLAGS_MASK
|
1632 _DRM_VBLANK_HIGH_CRTC_MASK
)) {
1633 DRM_ERROR("Unsupported type value 0x%x, supported mask 0x%x\n",
1634 vblwait
->request
.type
,
1635 (_DRM_VBLANK_TYPES_MASK
| _DRM_VBLANK_FLAGS_MASK
|
1636 _DRM_VBLANK_HIGH_CRTC_MASK
));
1640 flags
= vblwait
->request
.type
& _DRM_VBLANK_FLAGS_MASK
;
1641 high_pipe
= (vblwait
->request
.type
& _DRM_VBLANK_HIGH_CRTC_MASK
);
1643 pipe
= high_pipe
>> _DRM_VBLANK_HIGH_CRTC_SHIFT
;
1645 pipe
= flags
& _DRM_VBLANK_SECONDARY
? 1 : 0;
1646 if (pipe
>= dev
->num_crtcs
)
1649 vblank
= &dev
->vblank
[pipe
];
1651 ret
= drm_vblank_get(dev
, pipe
);
1653 DRM_DEBUG("failed to acquire vblank counter, %d\n", ret
);
1656 seq
= drm_vblank_count(dev
, pipe
);
1658 switch (vblwait
->request
.type
& _DRM_VBLANK_TYPES_MASK
) {
1659 case _DRM_VBLANK_RELATIVE
:
1660 vblwait
->request
.sequence
+= seq
;
1661 vblwait
->request
.type
&= ~_DRM_VBLANK_RELATIVE
;
1662 case _DRM_VBLANK_ABSOLUTE
:
1669 if (flags
& _DRM_VBLANK_EVENT
) {
1670 /* must hold on to the vblank ref until the event fires
1671 * drm_vblank_put will be called asynchronously
1673 return drm_queue_vblank_event(dev
, pipe
, vblwait
, file_priv
);
1676 if ((flags
& _DRM_VBLANK_NEXTONMISS
) &&
1677 (seq
- vblwait
->request
.sequence
) <= (1<<23)) {
1678 vblwait
->request
.sequence
= seq
+ 1;
1681 DRM_DEBUG("waiting on vblank count %d, crtc %u\n",
1682 vblwait
->request
.sequence
, pipe
);
1683 vblank
->last_wait
= vblwait
->request
.sequence
;
1684 DRM_WAIT_ON(ret
, vblank
->queue
, 3 * HZ
,
1685 (((drm_vblank_count(dev
, pipe
) -
1686 vblwait
->request
.sequence
) <= (1 << 23)) ||
1688 !dev
->irq_enabled
));
1690 if (ret
!= -EINTR
) {
1693 vblwait
->reply
.sequence
= drm_vblank_count_and_time(dev
, pipe
, &now
);
1694 vblwait
->reply
.tval_sec
= now
.tv_sec
;
1695 vblwait
->reply
.tval_usec
= now
.tv_usec
;
1697 DRM_DEBUG("returning %d to client\n",
1698 vblwait
->reply
.sequence
);
1700 DRM_DEBUG("vblank wait interrupted by signal\n");
1704 drm_vblank_put(dev
, pipe
);
1708 static void drm_handle_vblank_events(struct drm_device
*dev
, unsigned int pipe
)
1710 struct drm_pending_vblank_event
*e
, *t
;
1714 assert_spin_locked(&dev
->event_lock
);
1716 seq
= drm_vblank_count_and_time(dev
, pipe
, &now
);
1718 list_for_each_entry_safe(e
, t
, &dev
->vblank_event_list
, base
.link
) {
1719 if (e
->pipe
!= pipe
)
1721 if ((seq
- e
->event
.sequence
) > (1<<23))
1724 DRM_DEBUG("vblank event on %d, current %d\n",
1725 e
->event
.sequence
, seq
);
1727 list_del(&e
->base
.link
);
1728 drm_vblank_put(dev
, pipe
);
1729 send_vblank_event(dev
, e
, seq
, &now
);
1732 trace_drm_vblank_event(pipe
, seq
);
1736 * drm_handle_vblank - handle a vblank event
1738 * @pipe: index of CRTC where this event occurred
1740 * Drivers should call this routine in their vblank interrupt handlers to
1741 * update the vblank counter and send any signals that may be pending.
1743 * This is the legacy version of drm_crtc_handle_vblank().
1745 bool drm_handle_vblank(struct drm_device
*dev
, unsigned int pipe
)
1747 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1748 unsigned long irqflags
;
1750 if (WARN_ON_ONCE(!dev
->num_crtcs
))
1753 if (WARN_ON(pipe
>= dev
->num_crtcs
))
1756 spin_lock_irqsave(&dev
->event_lock
, irqflags
);
1758 /* Need timestamp lock to prevent concurrent execution with
1759 * vblank enable/disable, as this would cause inconsistent
1760 * or corrupted timestamps and vblank counts.
1762 spin_lock(&dev
->vblank_time_lock
);
1764 /* Vblank irq handling disabled. Nothing to do. */
1765 if (!vblank
->enabled
) {
1766 spin_unlock(&dev
->vblank_time_lock
);
1767 spin_unlock_irqrestore(&dev
->event_lock
, irqflags
);
1771 drm_update_vblank_count(dev
, pipe
, DRM_CALLED_FROM_VBLIRQ
);
1773 spin_unlock(&dev
->vblank_time_lock
);
1775 wake_up(&vblank
->queue
);
1776 drm_handle_vblank_events(dev
, pipe
);
1778 spin_unlock_irqrestore(&dev
->event_lock
, irqflags
);
1782 EXPORT_SYMBOL(drm_handle_vblank
);
1785 * drm_crtc_handle_vblank - handle a vblank event
1786 * @crtc: where this event occurred
1788 * Drivers should call this routine in their vblank interrupt handlers to
1789 * update the vblank counter and send any signals that may be pending.
1791 * This is the native KMS version of drm_handle_vblank().
1794 * True if the event was successfully handled, false on failure.
1796 bool drm_crtc_handle_vblank(struct drm_crtc
*crtc
)
1798 return drm_handle_vblank(crtc
->dev
, drm_crtc_index(crtc
));
1800 EXPORT_SYMBOL(drm_crtc_handle_vblank
);
1803 * drm_vblank_no_hw_counter - "No hw counter" implementation of .get_vblank_counter()
1805 * @pipe: CRTC for which to read the counter
1807 * Drivers can plug this into the .get_vblank_counter() function if
1808 * there is no useable hardware frame counter available.
1813 u32
drm_vblank_no_hw_counter(struct drm_device
*dev
, unsigned int pipe
)
1817 EXPORT_SYMBOL(drm_vblank_no_hw_counter
);