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);
76 MODULE_PARM_DESC(vblankoffdelay
, "Delay until vblank irq auto-disable [msecs] (0: never disable, <0: disable immediately)");
77 MODULE_PARM_DESC(timestamp_precision_usec
, "Max. error on timestamps [usecs]");
78 MODULE_PARM_DESC(timestamp_monotonic
, "Use monotonic timestamps");
80 static void store_vblank(struct drm_device
*dev
, unsigned int pipe
,
82 struct timeval
*t_vblank
, u32 last
)
84 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
87 assert_spin_locked(&dev
->vblank_time_lock
);
91 /* All writers hold the spinlock, but readers are serialized by
92 * the latching of vblank->count below.
94 tslot
= vblank
->count
+ vblank_count_inc
;
95 vblanktimestamp(dev
, pipe
, tslot
) = *t_vblank
;
98 * vblank timestamp updates are protected on the write side with
99 * vblank_time_lock, but on the read side done locklessly using a
100 * sequence-lock on the vblank counter. Ensure correct ordering using
101 * memory barrriers. We need the barrier both before and also after the
102 * counter update to synchronize with the next timestamp write.
103 * The read-side barriers for this are in drm_vblank_count_and_time.
106 vblank
->count
+= vblank_count_inc
;
111 * drm_reset_vblank_timestamp - reset the last timestamp to the last vblank
113 * @pipe: index of CRTC for which to reset the timestamp
115 * Reset the stored timestamp for the current vblank count to correspond
116 * to the last vblank occurred.
118 * Only to be called from drm_vblank_on().
120 * Note: caller must hold dev->vbl_lock since this reads & writes
121 * device vblank fields.
123 static void drm_reset_vblank_timestamp(struct drm_device
*dev
, unsigned int pipe
)
127 struct timeval t_vblank
;
128 int count
= DRM_TIMESTAMP_MAXRETRIES
;
130 spin_lock(&dev
->vblank_time_lock
);
133 * sample the current counter to avoid random jumps
134 * when drm_vblank_enable() applies the diff
137 cur_vblank
= dev
->driver
->get_vblank_counter(dev
, pipe
);
138 rc
= drm_get_last_vbltimestamp(dev
, pipe
, &t_vblank
, 0);
139 } while (cur_vblank
!= dev
->driver
->get_vblank_counter(dev
, pipe
) && --count
> 0);
142 * Only reinitialize corresponding vblank timestamp if high-precision query
143 * available and didn't fail. Otherwise reinitialize delayed at next vblank
144 * interrupt and assign 0 for now, to mark the vblanktimestamp as invalid.
147 t_vblank
= (struct timeval
) {0, 0};
150 * +1 to make sure user will never see the same
151 * vblank counter value before and after a modeset
153 store_vblank(dev
, pipe
, 1, &t_vblank
, cur_vblank
);
155 spin_unlock(&dev
->vblank_time_lock
);
159 * drm_update_vblank_count - update the master vblank counter
161 * @pipe: counter to update
163 * Call back into the driver to update the appropriate vblank counter
164 * (specified by @pipe). Deal with wraparound, if it occurred, and
165 * update the last read value so we can deal with wraparound on the next
168 * Only necessary when going from off->on, to account for frames we
169 * didn't get an interrupt for.
171 * Note: caller must hold dev->vbl_lock since this reads & writes
172 * device vblank fields.
174 static void drm_update_vblank_count(struct drm_device
*dev
, unsigned int pipe
,
177 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
178 u32 cur_vblank
, diff
;
180 struct timeval t_vblank
;
181 int count
= DRM_TIMESTAMP_MAXRETRIES
;
182 int framedur_ns
= vblank
->framedur_ns
;
185 * Interrupts were disabled prior to this call, so deal with counter
187 * NOTE! It's possible we lost a full dev->max_vblank_count + 1 events
188 * here if the register is small or we had vblank interrupts off for
191 * We repeat the hardware vblank counter & timestamp query until
192 * we get consistent results. This to prevent races between gpu
193 * updating its hardware counter while we are retrieving the
194 * corresponding vblank timestamp.
197 cur_vblank
= dev
->driver
->get_vblank_counter(dev
, pipe
);
198 rc
= drm_get_last_vbltimestamp(dev
, pipe
, &t_vblank
, flags
);
199 } while (cur_vblank
!= dev
->driver
->get_vblank_counter(dev
, pipe
) && --count
> 0);
201 if (dev
->max_vblank_count
!= 0) {
202 /* trust the hw counter when it's around */
203 diff
= (cur_vblank
- vblank
->last
) & dev
->max_vblank_count
;
204 } else if (rc
&& framedur_ns
) {
205 const struct timeval
*t_old
;
208 t_old
= &vblanktimestamp(dev
, pipe
, vblank
->count
);
209 diff_ns
= timeval_to_ns(&t_vblank
) - timeval_to_ns(t_old
);
212 * Figure out how many vblanks we've missed based
213 * on the difference in the timestamps and the
214 * frame/field duration.
216 diff
= DIV_ROUND_CLOSEST_ULL(diff_ns
, framedur_ns
);
218 if (diff
== 0 && flags
& DRM_CALLED_FROM_VBLIRQ
)
219 DRM_DEBUG_VBL("crtc %u: Redundant vblirq ignored."
220 " diff_ns = %lld, framedur_ns = %d)\n",
221 pipe
, (long long) diff_ns
, framedur_ns
);
223 /* some kind of default for drivers w/o accurate vbl timestamping */
224 diff
= (flags
& DRM_CALLED_FROM_VBLIRQ
) != 0;
227 DRM_DEBUG_VBL("updating vblank count on crtc %u:"
228 " current=%u, diff=%u, hw=%u hw_last=%u\n",
229 pipe
, vblank
->count
, diff
, cur_vblank
, vblank
->last
);
232 WARN_ON_ONCE(cur_vblank
!= vblank
->last
);
237 * Only reinitialize corresponding vblank timestamp if high-precision query
238 * available and didn't fail, or we were called from the vblank interrupt.
239 * Otherwise reinitialize delayed at next vblank interrupt and assign 0
240 * for now, to mark the vblanktimestamp as invalid.
242 if (!rc
&& (flags
& DRM_CALLED_FROM_VBLIRQ
) == 0)
243 t_vblank
= (struct timeval
) {0, 0};
245 store_vblank(dev
, pipe
, diff
, &t_vblank
, cur_vblank
);
249 * Disable vblank irq's on crtc, make sure that last vblank count
250 * of hardware and corresponding consistent software vblank counter
251 * are preserved, even if there are any spurious vblank irq's after
254 static void vblank_disable_and_save(struct drm_device
*dev
, unsigned int pipe
)
256 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
257 unsigned long irqflags
;
259 /* Prevent vblank irq processing while disabling vblank irqs,
260 * so no updates of timestamps or count can happen after we've
261 * disabled. Needed to prevent races in case of delayed irq's.
263 spin_lock_irqsave(&dev
->vblank_time_lock
, irqflags
);
266 * Only disable vblank interrupts if they're enabled. This avoids
267 * calling the ->disable_vblank() operation in atomic context with the
268 * hardware potentially runtime suspended.
270 if (vblank
->enabled
) {
271 dev
->driver
->disable_vblank(dev
, pipe
);
272 vblank
->enabled
= false;
276 * Always update the count and timestamp to maintain the
277 * appearance that the counter has been ticking all along until
278 * this time. This makes the count account for the entire time
279 * between drm_vblank_on() and drm_vblank_off().
281 drm_update_vblank_count(dev
, pipe
, 0);
283 spin_unlock_irqrestore(&dev
->vblank_time_lock
, irqflags
);
286 static void vblank_disable_fn(unsigned long arg
)
288 struct drm_vblank_crtc
*vblank
= (void *)arg
;
289 struct drm_device
*dev
= vblank
->dev
;
290 unsigned int pipe
= vblank
->pipe
;
291 unsigned long irqflags
;
293 if (!dev
->vblank_disable_allowed
)
296 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
297 if (atomic_read(&vblank
->refcount
) == 0 && vblank
->enabled
) {
298 DRM_DEBUG("disabling vblank on crtc %u\n", pipe
);
299 vblank_disable_and_save(dev
, pipe
);
301 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
305 * drm_vblank_cleanup - cleanup vblank support
308 * This function cleans up any resources allocated in drm_vblank_init.
310 void drm_vblank_cleanup(struct drm_device
*dev
)
314 /* Bail if the driver didn't call drm_vblank_init() */
315 if (dev
->num_crtcs
== 0)
318 for (pipe
= 0; pipe
< dev
->num_crtcs
; pipe
++) {
319 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
321 WARN_ON(vblank
->enabled
&&
322 drm_core_check_feature(dev
, DRIVER_MODESET
));
324 del_timer_sync(&vblank
->disable_timer
);
331 EXPORT_SYMBOL(drm_vblank_cleanup
);
334 * drm_vblank_init - initialize vblank support
336 * @num_crtcs: number of CRTCs supported by @dev
338 * This function initializes vblank support for @num_crtcs display pipelines.
341 * Zero on success or a negative error code on failure.
343 int drm_vblank_init(struct drm_device
*dev
, unsigned int num_crtcs
)
348 spin_lock_init(&dev
->vbl_lock
);
349 spin_lock_init(&dev
->vblank_time_lock
);
351 dev
->num_crtcs
= num_crtcs
;
353 dev
->vblank
= kcalloc(num_crtcs
, sizeof(*dev
->vblank
), GFP_KERNEL
);
357 for (i
= 0; i
< num_crtcs
; i
++) {
358 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[i
];
362 init_waitqueue_head(&vblank
->queue
);
363 setup_timer(&vblank
->disable_timer
, vblank_disable_fn
,
364 (unsigned long)vblank
);
367 DRM_INFO("Supports vblank timestamp caching Rev 2 (21.10.2013).\n");
369 /* Driver specific high-precision vblank timestamping supported? */
370 if (dev
->driver
->get_vblank_timestamp
)
371 DRM_INFO("Driver supports precise vblank timestamp query.\n");
373 DRM_INFO("No driver support for vblank timestamp query.\n");
375 /* Must have precise timestamping for reliable vblank instant disable */
376 if (dev
->vblank_disable_immediate
&& !dev
->driver
->get_vblank_timestamp
) {
377 dev
->vblank_disable_immediate
= false;
378 DRM_INFO("Setting vblank_disable_immediate to false because "
379 "get_vblank_timestamp == NULL\n");
382 dev
->vblank_disable_allowed
= false;
390 EXPORT_SYMBOL(drm_vblank_init
);
392 static void drm_irq_vgaarb_nokms(void *cookie
, bool state
)
394 struct drm_device
*dev
= cookie
;
396 if (dev
->driver
->vgaarb_irq
) {
397 dev
->driver
->vgaarb_irq(dev
, state
);
401 if (!dev
->irq_enabled
)
405 if (dev
->driver
->irq_uninstall
)
406 dev
->driver
->irq_uninstall(dev
);
408 if (dev
->driver
->irq_preinstall
)
409 dev
->driver
->irq_preinstall(dev
);
410 if (dev
->driver
->irq_postinstall
)
411 dev
->driver
->irq_postinstall(dev
);
416 * drm_irq_install - install IRQ handler
418 * @irq: IRQ number to install the handler for
420 * Initializes the IRQ related data. Installs the handler, calling the driver
421 * irq_preinstall() and irq_postinstall() functions before and after the
424 * This is the simplified helper interface provided for drivers with no special
425 * needs. Drivers which need to install interrupt handlers for multiple
426 * interrupts must instead set drm_device->irq_enabled to signal the DRM core
427 * that vblank interrupts are available.
430 * Zero on success or a negative error code on failure.
432 int drm_irq_install(struct drm_device
*dev
, int irq
)
435 unsigned long sh_flags
= 0;
437 if (!drm_core_check_feature(dev
, DRIVER_HAVE_IRQ
))
443 /* Driver must have been initialized */
444 if (!dev
->dev_private
)
447 if (dev
->irq_enabled
)
449 dev
->irq_enabled
= true;
451 DRM_DEBUG("irq=%d\n", irq
);
453 /* Before installing handler */
454 if (dev
->driver
->irq_preinstall
)
455 dev
->driver
->irq_preinstall(dev
);
457 /* Install handler */
458 if (drm_core_check_feature(dev
, DRIVER_IRQ_SHARED
))
459 sh_flags
= IRQF_SHARED
;
461 ret
= request_irq(irq
, dev
->driver
->irq_handler
,
462 sh_flags
, dev
->driver
->name
, dev
);
465 dev
->irq_enabled
= false;
469 if (!drm_core_check_feature(dev
, DRIVER_MODESET
))
470 vga_client_register(dev
->pdev
, (void *)dev
, drm_irq_vgaarb_nokms
, NULL
);
472 /* After installing handler */
473 if (dev
->driver
->irq_postinstall
)
474 ret
= dev
->driver
->irq_postinstall(dev
);
477 dev
->irq_enabled
= false;
478 if (!drm_core_check_feature(dev
, DRIVER_MODESET
))
479 vga_client_register(dev
->pdev
, NULL
, NULL
, NULL
);
487 EXPORT_SYMBOL(drm_irq_install
);
490 * drm_irq_uninstall - uninstall the IRQ handler
493 * Calls the driver's irq_uninstall() function and unregisters the IRQ handler.
494 * This should only be called by drivers which used drm_irq_install() to set up
495 * their interrupt handler. Other drivers must only reset
496 * drm_device->irq_enabled to false.
498 * Note that for kernel modesetting drivers it is a bug if this function fails.
499 * The sanity checks are only to catch buggy user modesetting drivers which call
500 * the same function through an ioctl.
503 * Zero on success or a negative error code on failure.
505 int drm_irq_uninstall(struct drm_device
*dev
)
507 unsigned long irqflags
;
511 if (!drm_core_check_feature(dev
, DRIVER_HAVE_IRQ
))
514 irq_enabled
= dev
->irq_enabled
;
515 dev
->irq_enabled
= false;
518 * Wake up any waiters so they don't hang. This is just to paper over
519 * isssues for UMS drivers which aren't in full control of their
520 * vblank/irq handling. KMS drivers must ensure that vblanks are all
521 * disabled when uninstalling the irq handler.
523 if (dev
->num_crtcs
) {
524 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
525 for (i
= 0; i
< dev
->num_crtcs
; i
++) {
526 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[i
];
528 if (!vblank
->enabled
)
531 WARN_ON(drm_core_check_feature(dev
, DRIVER_MODESET
));
533 vblank_disable_and_save(dev
, i
);
534 wake_up(&vblank
->queue
);
536 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
542 DRM_DEBUG("irq=%d\n", dev
->irq
);
544 if (!drm_core_check_feature(dev
, DRIVER_MODESET
))
545 vga_client_register(dev
->pdev
, NULL
, NULL
, NULL
);
547 if (dev
->driver
->irq_uninstall
)
548 dev
->driver
->irq_uninstall(dev
);
550 free_irq(dev
->irq
, dev
);
554 EXPORT_SYMBOL(drm_irq_uninstall
);
559 * \param inode device inode.
560 * \param file_priv DRM file private.
561 * \param cmd command.
562 * \param arg user argument, pointing to a drm_control structure.
563 * \return zero on success or a negative number on failure.
565 * Calls irq_install() or irq_uninstall() according to \p arg.
567 int drm_control(struct drm_device
*dev
, void *data
,
568 struct drm_file
*file_priv
)
570 struct drm_control
*ctl
= data
;
573 /* if we haven't irq we fallback for compatibility reasons -
574 * this used to be a separate function in drm_dma.h
577 if (!drm_core_check_feature(dev
, DRIVER_HAVE_IRQ
))
579 if (drm_core_check_feature(dev
, DRIVER_MODESET
))
581 /* UMS was only ever support on pci devices. */
582 if (WARN_ON(!dev
->pdev
))
586 case DRM_INST_HANDLER
:
587 irq
= dev
->pdev
->irq
;
589 if (dev
->if_version
< DRM_IF_VERSION(1, 2) &&
592 mutex_lock(&dev
->struct_mutex
);
593 ret
= drm_irq_install(dev
, irq
);
594 mutex_unlock(&dev
->struct_mutex
);
597 case DRM_UNINST_HANDLER
:
598 mutex_lock(&dev
->struct_mutex
);
599 ret
= drm_irq_uninstall(dev
);
600 mutex_unlock(&dev
->struct_mutex
);
609 * drm_calc_timestamping_constants - calculate vblank timestamp constants
610 * @crtc: drm_crtc whose timestamp constants should be updated.
611 * @mode: display mode containing the scanout timings
613 * Calculate and store various constants which are later
614 * needed by vblank and swap-completion timestamping, e.g,
615 * by drm_calc_vbltimestamp_from_scanoutpos(). They are
616 * derived from CRTC's true scanout timing, so they take
617 * things like panel scaling or other adjustments into account.
619 void drm_calc_timestamping_constants(struct drm_crtc
*crtc
,
620 const struct drm_display_mode
*mode
)
622 struct drm_device
*dev
= crtc
->dev
;
623 unsigned int pipe
= drm_crtc_index(crtc
);
624 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
625 int linedur_ns
= 0, framedur_ns
= 0;
626 int dotclock
= mode
->crtc_clock
;
631 if (WARN_ON(pipe
>= dev
->num_crtcs
))
634 /* Valid dotclock? */
636 int frame_size
= mode
->crtc_htotal
* mode
->crtc_vtotal
;
639 * Convert scanline length in pixels and video
640 * dot clock to line duration and frame duration
643 linedur_ns
= div_u64((u64
) mode
->crtc_htotal
* 1000000, dotclock
);
644 framedur_ns
= div_u64((u64
) frame_size
* 1000000, dotclock
);
647 * Fields of interlaced scanout modes are only half a frame duration.
649 if (mode
->flags
& DRM_MODE_FLAG_INTERLACE
)
652 DRM_ERROR("crtc %u: Can't calculate constants, dotclock = 0!\n",
655 vblank
->linedur_ns
= linedur_ns
;
656 vblank
->framedur_ns
= framedur_ns
;
658 DRM_DEBUG("crtc %u: hwmode: htotal %d, vtotal %d, vdisplay %d\n",
659 crtc
->base
.id
, mode
->crtc_htotal
,
660 mode
->crtc_vtotal
, mode
->crtc_vdisplay
);
661 DRM_DEBUG("crtc %u: clock %d kHz framedur %d linedur %d\n",
662 crtc
->base
.id
, dotclock
, framedur_ns
, linedur_ns
);
664 EXPORT_SYMBOL(drm_calc_timestamping_constants
);
667 * drm_calc_vbltimestamp_from_scanoutpos - precise vblank timestamp helper
669 * @pipe: index of CRTC whose vblank timestamp to retrieve
670 * @max_error: Desired maximum allowable error in timestamps (nanosecs)
671 * On return contains true maximum error of timestamp
672 * @vblank_time: Pointer to struct timeval which should receive the timestamp
673 * @flags: Flags to pass to driver:
675 * DRM_CALLED_FROM_VBLIRQ = If function is called from vbl IRQ handler
676 * @mode: mode which defines the scanout timings
678 * Implements calculation of exact vblank timestamps from given drm_display_mode
679 * timings and current video scanout position of a CRTC. This can be called from
680 * within get_vblank_timestamp() implementation of a kms driver to implement the
681 * actual timestamping.
683 * Should return timestamps conforming to the OML_sync_control OpenML
684 * extension specification. The timestamp corresponds to the end of
685 * the vblank interval, aka start of scanout of topmost-leftmost display
686 * pixel in the following video frame.
688 * Requires support for optional dev->driver->get_scanout_position()
689 * in kms driver, plus a bit of setup code to provide a drm_display_mode
690 * that corresponds to the true scanout timing.
692 * The current implementation only handles standard video modes. It
693 * returns as no operation if a doublescan or interlaced video mode is
694 * active. Higher level code is expected to handle this.
697 * Negative value on error, failure or if not supported in current
700 * -EINVAL - Invalid CRTC.
701 * -EAGAIN - Temporary unavailable, e.g., called before initial modeset.
702 * -ENOTSUPP - Function not supported in current display mode.
703 * -EIO - Failed, e.g., due to failed scanout position query.
705 * Returns or'ed positive status flags on success:
707 * DRM_VBLANKTIME_SCANOUTPOS_METHOD - Signal this method used for timestamping.
708 * DRM_VBLANKTIME_INVBL - Timestamp taken while scanout was in vblank interval.
711 int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device
*dev
,
714 struct timeval
*vblank_time
,
716 const struct drm_display_mode
*mode
)
718 struct timeval tv_etime
;
719 ktime_t stime
, etime
;
720 unsigned int vbl_status
;
721 int ret
= DRM_VBLANKTIME_SCANOUTPOS_METHOD
;
723 int delta_ns
, duration_ns
;
725 if (pipe
>= dev
->num_crtcs
) {
726 DRM_ERROR("Invalid crtc %u\n", pipe
);
730 /* Scanout position query not supported? Should not happen. */
731 if (!dev
->driver
->get_scanout_position
) {
732 DRM_ERROR("Called from driver w/o get_scanout_position()!?\n");
736 /* If mode timing undefined, just return as no-op:
737 * Happens during initial modesetting of a crtc.
739 if (mode
->crtc_clock
== 0) {
740 DRM_DEBUG("crtc %u: Noop due to uninitialized mode.\n", pipe
);
744 /* Get current scanout position with system timestamp.
745 * Repeat query up to DRM_TIMESTAMP_MAXRETRIES times
746 * if single query takes longer than max_error nanoseconds.
748 * This guarantees a tight bound on maximum error if
749 * code gets preempted or delayed for some reason.
751 for (i
= 0; i
< DRM_TIMESTAMP_MAXRETRIES
; i
++) {
753 * Get vertical and horizontal scanout position vpos, hpos,
754 * and bounding timestamps stime, etime, pre/post query.
756 vbl_status
= dev
->driver
->get_scanout_position(dev
, pipe
, flags
,
761 /* Return as no-op if scanout query unsupported or failed. */
762 if (!(vbl_status
& DRM_SCANOUTPOS_VALID
)) {
763 DRM_DEBUG("crtc %u : scanoutpos query failed [0x%x].\n",
768 /* Compute uncertainty in timestamp of scanout position query. */
769 duration_ns
= ktime_to_ns(etime
) - ktime_to_ns(stime
);
771 /* Accept result with < max_error nsecs timing uncertainty. */
772 if (duration_ns
<= *max_error
)
776 /* Noisy system timing? */
777 if (i
== DRM_TIMESTAMP_MAXRETRIES
) {
778 DRM_DEBUG("crtc %u: Noisy timestamp %d us > %d us [%d reps].\n",
779 pipe
, duration_ns
/1000, *max_error
/1000, i
);
782 /* Return upper bound of timestamp precision error. */
783 *max_error
= duration_ns
;
785 /* Check if in vblank area:
786 * vpos is >=0 in video scanout area, but negative
787 * within vblank area, counting down the number of lines until
790 if (vbl_status
& DRM_SCANOUTPOS_IN_VBLANK
)
791 ret
|= DRM_VBLANKTIME_IN_VBLANK
;
793 /* Convert scanout position into elapsed time at raw_time query
794 * since start of scanout at first display scanline. delta_ns
795 * can be negative if start of scanout hasn't happened yet.
797 delta_ns
= div_s64(1000000LL * (vpos
* mode
->crtc_htotal
+ hpos
),
800 if (!drm_timestamp_monotonic
)
801 etime
= ktime_mono_to_real(etime
);
803 /* save this only for debugging purposes */
804 tv_etime
= ktime_to_timeval(etime
);
805 /* Subtract time delta from raw timestamp to get final
806 * vblank_time timestamp for end of vblank.
809 etime
= ktime_add_ns(etime
, -delta_ns
);
811 etime
= ktime_sub_ns(etime
, delta_ns
);
812 *vblank_time
= ktime_to_timeval(etime
);
814 DRM_DEBUG_VBL("crtc %u : v 0x%x p(%d,%d)@ %ld.%ld -> %ld.%ld [e %d us, %d rep]\n",
815 pipe
, vbl_status
, hpos
, vpos
,
816 (long)tv_etime
.tv_sec
, (long)tv_etime
.tv_usec
,
817 (long)vblank_time
->tv_sec
, (long)vblank_time
->tv_usec
,
818 duration_ns
/1000, i
);
822 EXPORT_SYMBOL(drm_calc_vbltimestamp_from_scanoutpos
);
824 static struct timeval
get_drm_timestamp(void)
828 now
= drm_timestamp_monotonic
? ktime_get() : ktime_get_real();
829 return ktime_to_timeval(now
);
833 * drm_get_last_vbltimestamp - retrieve raw timestamp for the most recent
836 * @pipe: index of CRTC whose vblank timestamp to retrieve
837 * @tvblank: Pointer to target struct timeval which should receive the timestamp
838 * @flags: Flags to pass to driver:
840 * DRM_CALLED_FROM_VBLIRQ = If function is called from vbl IRQ handler
842 * Fetches the system timestamp corresponding to the time of the most recent
843 * vblank interval on specified CRTC. May call into kms-driver to
844 * compute the timestamp with a high-precision GPU specific method.
846 * Returns zero if timestamp originates from uncorrected do_gettimeofday()
847 * call, i.e., it isn't very precisely locked to the true vblank.
850 * True if timestamp is considered to be very precise, false otherwise.
853 drm_get_last_vbltimestamp(struct drm_device
*dev
, unsigned int pipe
,
854 struct timeval
*tvblank
, unsigned flags
)
858 /* Define requested maximum error on timestamps (nanoseconds). */
859 int max_error
= (int) drm_timestamp_precision
* 1000;
861 /* Query driver if possible and precision timestamping enabled. */
862 if (dev
->driver
->get_vblank_timestamp
&& (max_error
> 0)) {
863 ret
= dev
->driver
->get_vblank_timestamp(dev
, pipe
, &max_error
,
869 /* GPU high precision timestamp query unsupported or failed.
870 * Return current monotonic/gettimeofday timestamp as best estimate.
872 *tvblank
= get_drm_timestamp();
878 * drm_vblank_count - retrieve "cooked" vblank counter value
880 * @pipe: index of CRTC for which to retrieve the counter
882 * Fetches the "cooked" vblank count value that represents the number of
883 * vblank events since the system was booted, including lost events due to
884 * modesetting activity.
886 * This is the legacy version of drm_crtc_vblank_count().
889 * The software vblank counter.
891 u32
drm_vblank_count(struct drm_device
*dev
, unsigned int pipe
)
893 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
895 if (WARN_ON(pipe
>= dev
->num_crtcs
))
898 return vblank
->count
;
900 EXPORT_SYMBOL(drm_vblank_count
);
903 * drm_crtc_vblank_count - retrieve "cooked" vblank counter value
904 * @crtc: which counter to retrieve
906 * Fetches the "cooked" vblank count value that represents the number of
907 * vblank events since the system was booted, including lost events due to
908 * modesetting activity.
910 * This is the native KMS version of drm_vblank_count().
913 * The software vblank counter.
915 u32
drm_crtc_vblank_count(struct drm_crtc
*crtc
)
917 return drm_vblank_count(crtc
->dev
, drm_crtc_index(crtc
));
919 EXPORT_SYMBOL(drm_crtc_vblank_count
);
922 * drm_vblank_count_and_time - retrieve "cooked" vblank counter value and the
923 * system timestamp corresponding to that vblank counter value.
925 * @pipe: index of CRTC whose counter to retrieve
926 * @vblanktime: Pointer to struct timeval to receive the vblank timestamp.
928 * Fetches the "cooked" vblank count value that represents the number of
929 * vblank events since the system was booted, including lost events due to
930 * modesetting activity. Returns corresponding system timestamp of the time
931 * of the vblank interval that corresponds to the current vblank counter value.
933 * This is the legacy version of drm_crtc_vblank_count_and_time().
935 u32
drm_vblank_count_and_time(struct drm_device
*dev
, unsigned int pipe
,
936 struct timeval
*vblanktime
)
938 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
939 int count
= DRM_TIMESTAMP_MAXRETRIES
;
942 if (WARN_ON(pipe
>= dev
->num_crtcs
))
946 * Vblank timestamps are read lockless. To ensure consistency the vblank
947 * counter is rechecked and ordering is ensured using memory barriers.
948 * This works like a seqlock. The write-side barriers are in store_vblank.
951 cur_vblank
= vblank
->count
;
953 *vblanktime
= vblanktimestamp(dev
, pipe
, cur_vblank
);
955 } while (cur_vblank
!= vblank
->count
&& --count
> 0);
959 EXPORT_SYMBOL(drm_vblank_count_and_time
);
962 * drm_crtc_vblank_count_and_time - retrieve "cooked" vblank counter value
963 * and the system timestamp corresponding to that vblank counter value
964 * @crtc: which counter to retrieve
965 * @vblanktime: Pointer to struct timeval to receive the vblank timestamp.
967 * Fetches the "cooked" vblank count value that represents the number of
968 * vblank events since the system was booted, including lost events due to
969 * modesetting activity. Returns corresponding system timestamp of the time
970 * of the vblank interval that corresponds to the current vblank counter value.
972 * This is the native KMS version of drm_vblank_count_and_time().
974 u32
drm_crtc_vblank_count_and_time(struct drm_crtc
*crtc
,
975 struct timeval
*vblanktime
)
977 return drm_vblank_count_and_time(crtc
->dev
, drm_crtc_index(crtc
),
980 EXPORT_SYMBOL(drm_crtc_vblank_count_and_time
);
982 static void send_vblank_event(struct drm_device
*dev
,
983 struct drm_pending_vblank_event
*e
,
984 unsigned long seq
, struct timeval
*now
)
986 assert_spin_locked(&dev
->event_lock
);
988 e
->event
.sequence
= seq
;
989 e
->event
.tv_sec
= now
->tv_sec
;
990 e
->event
.tv_usec
= now
->tv_usec
;
992 list_add_tail(&e
->base
.link
,
993 &e
->base
.file_priv
->event_list
);
994 wake_up_interruptible(&e
->base
.file_priv
->event_wait
);
995 trace_drm_vblank_event_delivered(e
->base
.pid
, e
->pipe
,
1000 * drm_arm_vblank_event - arm vblank event after pageflip
1003 * @e: the event to prepare to send
1005 * A lot of drivers need to generate vblank events for the very next vblank
1006 * interrupt. For example when the page flip interrupt happens when the page
1007 * flip gets armed, but not when it actually executes within the next vblank
1008 * period. This helper function implements exactly the required vblank arming
1011 * Caller must hold event lock. Caller must also hold a vblank reference for
1012 * the event @e, which will be dropped when the next vblank arrives.
1014 * This is the legacy version of drm_crtc_arm_vblank_event().
1016 void drm_arm_vblank_event(struct drm_device
*dev
, unsigned int pipe
,
1017 struct drm_pending_vblank_event
*e
)
1019 assert_spin_locked(&dev
->event_lock
);
1022 e
->event
.sequence
= drm_vblank_count(dev
, pipe
);
1023 list_add_tail(&e
->base
.link
, &dev
->vblank_event_list
);
1025 EXPORT_SYMBOL(drm_arm_vblank_event
);
1028 * drm_crtc_arm_vblank_event - arm vblank event after pageflip
1029 * @crtc: the source CRTC of the vblank event
1030 * @e: the event to send
1032 * A lot of drivers need to generate vblank events for the very next vblank
1033 * interrupt. For example when the page flip interrupt happens when the page
1034 * flip gets armed, but not when it actually executes within the next vblank
1035 * period. This helper function implements exactly the required vblank arming
1038 * Caller must hold event lock. Caller must also hold a vblank reference for
1039 * the event @e, which will be dropped when the next vblank arrives.
1041 * This is the native KMS version of drm_arm_vblank_event().
1043 void drm_crtc_arm_vblank_event(struct drm_crtc
*crtc
,
1044 struct drm_pending_vblank_event
*e
)
1046 drm_arm_vblank_event(crtc
->dev
, drm_crtc_index(crtc
), e
);
1048 EXPORT_SYMBOL(drm_crtc_arm_vblank_event
);
1051 * drm_send_vblank_event - helper to send vblank event after pageflip
1054 * @e: the event to send
1056 * Updates sequence # and timestamp on event, and sends it to userspace.
1057 * Caller must hold event lock.
1059 * This is the legacy version of drm_crtc_send_vblank_event().
1061 void drm_send_vblank_event(struct drm_device
*dev
, unsigned int pipe
,
1062 struct drm_pending_vblank_event
*e
)
1067 if (dev
->num_crtcs
> 0) {
1068 seq
= drm_vblank_count_and_time(dev
, pipe
, &now
);
1072 now
= get_drm_timestamp();
1075 send_vblank_event(dev
, e
, seq
, &now
);
1077 EXPORT_SYMBOL(drm_send_vblank_event
);
1080 * drm_crtc_send_vblank_event - helper to send vblank event after pageflip
1081 * @crtc: the source CRTC of the vblank event
1082 * @e: the event to send
1084 * Updates sequence # and timestamp on event, and sends it to userspace.
1085 * Caller must hold event lock.
1087 * This is the native KMS version of drm_send_vblank_event().
1089 void drm_crtc_send_vblank_event(struct drm_crtc
*crtc
,
1090 struct drm_pending_vblank_event
*e
)
1092 drm_send_vblank_event(crtc
->dev
, drm_crtc_index(crtc
), e
);
1094 EXPORT_SYMBOL(drm_crtc_send_vblank_event
);
1097 * drm_vblank_enable - enable the vblank interrupt on a CRTC
1102 * Zero on success or a negative error code on failure.
1104 static int drm_vblank_enable(struct drm_device
*dev
, unsigned int pipe
)
1106 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1109 assert_spin_locked(&dev
->vbl_lock
);
1111 spin_lock(&dev
->vblank_time_lock
);
1113 if (!vblank
->enabled
) {
1115 * Enable vblank irqs under vblank_time_lock protection.
1116 * All vblank count & timestamp updates are held off
1117 * until we are done reinitializing master counter and
1118 * timestamps. Filtercode in drm_handle_vblank() will
1119 * prevent double-accounting of same vblank interval.
1121 ret
= dev
->driver
->enable_vblank(dev
, pipe
);
1122 DRM_DEBUG("enabling vblank on crtc %u, ret: %d\n", pipe
, ret
);
1124 atomic_dec(&vblank
->refcount
);
1126 vblank
->enabled
= true;
1127 drm_update_vblank_count(dev
, pipe
, 0);
1131 spin_unlock(&dev
->vblank_time_lock
);
1137 * drm_vblank_get - get a reference count on vblank events
1139 * @pipe: index of CRTC to own
1141 * Acquire a reference count on vblank events to avoid having them disabled
1144 * This is the legacy version of drm_crtc_vblank_get().
1147 * Zero on success or a negative error code on failure.
1149 int drm_vblank_get(struct drm_device
*dev
, unsigned int pipe
)
1151 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1152 unsigned long irqflags
;
1155 if (!dev
->num_crtcs
)
1158 if (WARN_ON(pipe
>= dev
->num_crtcs
))
1161 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
1162 /* Going from 0->1 means we have to enable interrupts again */
1163 if (atomic_add_return(1, &vblank
->refcount
) == 1) {
1164 ret
= drm_vblank_enable(dev
, pipe
);
1166 if (!vblank
->enabled
) {
1167 atomic_dec(&vblank
->refcount
);
1171 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
1175 EXPORT_SYMBOL(drm_vblank_get
);
1178 * drm_crtc_vblank_get - get a reference count on vblank events
1179 * @crtc: which CRTC to own
1181 * Acquire a reference count on vblank events to avoid having them disabled
1184 * This is the native kms version of drm_vblank_get().
1187 * Zero on success or a negative error code on failure.
1189 int drm_crtc_vblank_get(struct drm_crtc
*crtc
)
1191 return drm_vblank_get(crtc
->dev
, drm_crtc_index(crtc
));
1193 EXPORT_SYMBOL(drm_crtc_vblank_get
);
1196 * drm_vblank_put - release ownership of vblank events
1198 * @pipe: index of CRTC to release
1200 * Release ownership of a given vblank counter, turning off interrupts
1201 * if possible. Disable interrupts after drm_vblank_offdelay milliseconds.
1203 * This is the legacy version of drm_crtc_vblank_put().
1205 void drm_vblank_put(struct drm_device
*dev
, unsigned int pipe
)
1207 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1209 if (WARN_ON(pipe
>= dev
->num_crtcs
))
1212 if (WARN_ON(atomic_read(&vblank
->refcount
) == 0))
1215 /* Last user schedules interrupt disable */
1216 if (atomic_dec_and_test(&vblank
->refcount
)) {
1217 if (drm_vblank_offdelay
== 0)
1219 else if (dev
->vblank_disable_immediate
|| drm_vblank_offdelay
< 0)
1220 vblank_disable_fn((unsigned long)vblank
);
1222 mod_timer(&vblank
->disable_timer
,
1223 jiffies
+ ((drm_vblank_offdelay
* HZ
)/1000));
1226 EXPORT_SYMBOL(drm_vblank_put
);
1229 * drm_crtc_vblank_put - give up ownership of vblank events
1230 * @crtc: which counter to give up
1232 * Release ownership of a given vblank counter, turning off interrupts
1233 * if possible. Disable interrupts after drm_vblank_offdelay milliseconds.
1235 * This is the native kms version of drm_vblank_put().
1237 void drm_crtc_vblank_put(struct drm_crtc
*crtc
)
1239 drm_vblank_put(crtc
->dev
, drm_crtc_index(crtc
));
1241 EXPORT_SYMBOL(drm_crtc_vblank_put
);
1244 * drm_wait_one_vblank - wait for one vblank
1248 * This waits for one vblank to pass on @pipe, using the irq driver interfaces.
1249 * It is a failure to call this when the vblank irq for @pipe is disabled, e.g.
1250 * due to lack of driver support or because the crtc is off.
1252 void drm_wait_one_vblank(struct drm_device
*dev
, unsigned int pipe
)
1254 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1258 if (WARN_ON(pipe
>= dev
->num_crtcs
))
1261 ret
= drm_vblank_get(dev
, pipe
);
1262 if (WARN(ret
, "vblank not available on crtc %i, ret=%i\n", pipe
, ret
))
1265 last
= drm_vblank_count(dev
, pipe
);
1267 ret
= wait_event_timeout(vblank
->queue
,
1268 last
!= drm_vblank_count(dev
, pipe
),
1269 msecs_to_jiffies(100));
1271 WARN(ret
== 0, "vblank wait timed out on crtc %i\n", pipe
);
1273 drm_vblank_put(dev
, pipe
);
1275 EXPORT_SYMBOL(drm_wait_one_vblank
);
1278 * drm_crtc_wait_one_vblank - wait for one vblank
1281 * This waits for one vblank to pass on @crtc, using the irq driver interfaces.
1282 * It is a failure to call this when the vblank irq for @crtc is disabled, e.g.
1283 * due to lack of driver support or because the crtc is off.
1285 void drm_crtc_wait_one_vblank(struct drm_crtc
*crtc
)
1287 drm_wait_one_vblank(crtc
->dev
, drm_crtc_index(crtc
));
1289 EXPORT_SYMBOL(drm_crtc_wait_one_vblank
);
1292 * drm_vblank_off - disable vblank events on a CRTC
1296 * Drivers can use this function to shut down the vblank interrupt handling when
1297 * disabling a crtc. This function ensures that the latest vblank frame count is
1298 * stored so that drm_vblank_on() can restore it again.
1300 * Drivers must use this function when the hardware vblank counter can get
1301 * reset, e.g. when suspending.
1303 * This is the legacy version of drm_crtc_vblank_off().
1305 void drm_vblank_off(struct drm_device
*dev
, unsigned int pipe
)
1307 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1308 struct drm_pending_vblank_event
*e
, *t
;
1310 unsigned long irqflags
;
1313 if (WARN_ON(pipe
>= dev
->num_crtcs
))
1316 spin_lock_irqsave(&dev
->event_lock
, irqflags
);
1318 spin_lock(&dev
->vbl_lock
);
1319 vblank_disable_and_save(dev
, pipe
);
1320 wake_up(&vblank
->queue
);
1323 * Prevent subsequent drm_vblank_get() from re-enabling
1324 * the vblank interrupt by bumping the refcount.
1326 if (!vblank
->inmodeset
) {
1327 atomic_inc(&vblank
->refcount
);
1328 vblank
->inmodeset
= 1;
1330 spin_unlock(&dev
->vbl_lock
);
1332 /* Send any queued vblank events, lest the natives grow disquiet */
1333 seq
= drm_vblank_count_and_time(dev
, pipe
, &now
);
1335 list_for_each_entry_safe(e
, t
, &dev
->vblank_event_list
, base
.link
) {
1336 if (e
->pipe
!= pipe
)
1338 DRM_DEBUG("Sending premature vblank event on disable: "
1339 "wanted %d, current %d\n",
1340 e
->event
.sequence
, seq
);
1341 list_del(&e
->base
.link
);
1342 drm_vblank_put(dev
, pipe
);
1343 send_vblank_event(dev
, e
, seq
, &now
);
1345 spin_unlock_irqrestore(&dev
->event_lock
, irqflags
);
1347 EXPORT_SYMBOL(drm_vblank_off
);
1350 * drm_crtc_vblank_off - disable vblank events on a CRTC
1351 * @crtc: CRTC in question
1353 * Drivers can use this function to shut down the vblank interrupt handling when
1354 * disabling a crtc. This function ensures that the latest vblank frame count is
1355 * stored so that drm_vblank_on can restore it again.
1357 * Drivers must use this function when the hardware vblank counter can get
1358 * reset, e.g. when suspending.
1360 * This is the native kms version of drm_vblank_off().
1362 void drm_crtc_vblank_off(struct drm_crtc
*crtc
)
1364 drm_vblank_off(crtc
->dev
, drm_crtc_index(crtc
));
1366 EXPORT_SYMBOL(drm_crtc_vblank_off
);
1369 * drm_crtc_vblank_reset - reset vblank state to off on a CRTC
1370 * @crtc: CRTC in question
1372 * Drivers can use this function to reset the vblank state to off at load time.
1373 * Drivers should use this together with the drm_crtc_vblank_off() and
1374 * drm_crtc_vblank_on() functions. The difference compared to
1375 * drm_crtc_vblank_off() is that this function doesn't save the vblank counter
1376 * and hence doesn't need to call any driver hooks.
1378 void drm_crtc_vblank_reset(struct drm_crtc
*crtc
)
1380 struct drm_device
*dev
= crtc
->dev
;
1381 unsigned long irqflags
;
1382 unsigned int pipe
= drm_crtc_index(crtc
);
1383 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1385 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
1387 * Prevent subsequent drm_vblank_get() from enabling the vblank
1388 * interrupt by bumping the refcount.
1390 if (!vblank
->inmodeset
) {
1391 atomic_inc(&vblank
->refcount
);
1392 vblank
->inmodeset
= 1;
1394 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
1396 WARN_ON(!list_empty(&dev
->vblank_event_list
));
1398 EXPORT_SYMBOL(drm_crtc_vblank_reset
);
1401 * drm_vblank_on - enable vblank events on a CRTC
1405 * This functions restores the vblank interrupt state captured with
1406 * drm_vblank_off() again. Note that calls to drm_vblank_on() and
1407 * drm_vblank_off() can be unbalanced and so can also be unconditionally called
1408 * in driver load code to reflect the current hardware state of the crtc.
1410 * This is the legacy version of drm_crtc_vblank_on().
1412 void drm_vblank_on(struct drm_device
*dev
, unsigned int pipe
)
1414 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1415 unsigned long irqflags
;
1417 if (WARN_ON(pipe
>= dev
->num_crtcs
))
1420 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
1421 /* Drop our private "prevent drm_vblank_get" refcount */
1422 if (vblank
->inmodeset
) {
1423 atomic_dec(&vblank
->refcount
);
1424 vblank
->inmodeset
= 0;
1427 drm_reset_vblank_timestamp(dev
, pipe
);
1430 * re-enable interrupts if there are users left, or the
1431 * user wishes vblank interrupts to be enabled all the time.
1433 if (atomic_read(&vblank
->refcount
) != 0 ||
1434 (!dev
->vblank_disable_immediate
&& drm_vblank_offdelay
== 0))
1435 WARN_ON(drm_vblank_enable(dev
, pipe
));
1436 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
1438 EXPORT_SYMBOL(drm_vblank_on
);
1441 * drm_crtc_vblank_on - enable vblank events on a CRTC
1442 * @crtc: CRTC in question
1444 * This functions restores the vblank interrupt state captured with
1445 * drm_vblank_off() again. Note that calls to drm_vblank_on() and
1446 * drm_vblank_off() can be unbalanced and so can also be unconditionally called
1447 * in driver load code to reflect the current hardware state of the crtc.
1449 * This is the native kms version of drm_vblank_on().
1451 void drm_crtc_vblank_on(struct drm_crtc
*crtc
)
1453 drm_vblank_on(crtc
->dev
, drm_crtc_index(crtc
));
1455 EXPORT_SYMBOL(drm_crtc_vblank_on
);
1458 * drm_vblank_pre_modeset - account for vblanks across mode sets
1462 * Account for vblank events across mode setting events, which will likely
1463 * reset the hardware frame counter.
1465 * This is done by grabbing a temporary vblank reference to ensure that the
1466 * vblank interrupt keeps running across the modeset sequence. With this the
1467 * software-side vblank frame counting will ensure that there are no jumps or
1470 * Unfortunately this approach is racy and also doesn't work when the vblank
1471 * interrupt stops running, e.g. across system suspend resume. It is therefore
1472 * highly recommended that drivers use the newer drm_vblank_off() and
1473 * drm_vblank_on() instead. drm_vblank_pre_modeset() only works correctly when
1474 * using "cooked" software vblank frame counters and not relying on any hardware
1477 * Drivers must call drm_vblank_post_modeset() when re-enabling the same crtc
1480 void drm_vblank_pre_modeset(struct drm_device
*dev
, unsigned int pipe
)
1482 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1484 /* vblank is not initialized (IRQ not installed ?), or has been freed */
1485 if (!dev
->num_crtcs
)
1488 if (WARN_ON(pipe
>= dev
->num_crtcs
))
1492 * To avoid all the problems that might happen if interrupts
1493 * were enabled/disabled around or between these calls, we just
1494 * have the kernel take a reference on the CRTC (just once though
1495 * to avoid corrupting the count if multiple, mismatch calls occur),
1496 * so that interrupts remain enabled in the interim.
1498 if (!vblank
->inmodeset
) {
1499 vblank
->inmodeset
= 0x1;
1500 if (drm_vblank_get(dev
, pipe
) == 0)
1501 vblank
->inmodeset
|= 0x2;
1504 EXPORT_SYMBOL(drm_vblank_pre_modeset
);
1507 * drm_vblank_post_modeset - undo drm_vblank_pre_modeset changes
1511 * This function again drops the temporary vblank reference acquired in
1512 * drm_vblank_pre_modeset.
1514 void drm_vblank_post_modeset(struct drm_device
*dev
, unsigned int pipe
)
1516 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1517 unsigned long irqflags
;
1519 /* vblank is not initialized (IRQ not installed ?), or has been freed */
1520 if (!dev
->num_crtcs
)
1523 if (WARN_ON(pipe
>= dev
->num_crtcs
))
1526 if (vblank
->inmodeset
) {
1527 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
1528 dev
->vblank_disable_allowed
= true;
1529 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
1531 if (vblank
->inmodeset
& 0x2)
1532 drm_vblank_put(dev
, pipe
);
1534 vblank
->inmodeset
= 0;
1537 EXPORT_SYMBOL(drm_vblank_post_modeset
);
1540 * drm_modeset_ctl - handle vblank event counter changes across mode switch
1541 * @DRM_IOCTL_ARGS: standard ioctl arguments
1543 * Applications should call the %_DRM_PRE_MODESET and %_DRM_POST_MODESET
1544 * ioctls around modesetting so that any lost vblank events are accounted for.
1546 * Generally the counter will reset across mode sets. If interrupts are
1547 * enabled around this call, we don't have to do anything since the counter
1548 * will have already been incremented.
1550 int drm_modeset_ctl(struct drm_device
*dev
, void *data
,
1551 struct drm_file
*file_priv
)
1553 struct drm_modeset_ctl
*modeset
= data
;
1556 /* If drm_vblank_init() hasn't been called yet, just no-op */
1557 if (!dev
->num_crtcs
)
1560 /* KMS drivers handle this internally */
1561 if (drm_core_check_feature(dev
, DRIVER_MODESET
))
1564 pipe
= modeset
->crtc
;
1565 if (pipe
>= dev
->num_crtcs
)
1568 switch (modeset
->cmd
) {
1569 case _DRM_PRE_MODESET
:
1570 drm_vblank_pre_modeset(dev
, pipe
);
1572 case _DRM_POST_MODESET
:
1573 drm_vblank_post_modeset(dev
, pipe
);
1582 static int drm_queue_vblank_event(struct drm_device
*dev
, unsigned int pipe
,
1583 union drm_wait_vblank
*vblwait
,
1584 struct drm_file
*file_priv
)
1586 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1587 struct drm_pending_vblank_event
*e
;
1589 unsigned long flags
;
1593 e
= kzalloc(sizeof(*e
), GFP_KERNEL
);
1600 e
->base
.pid
= current
->pid
;
1601 e
->event
.base
.type
= DRM_EVENT_VBLANK
;
1602 e
->event
.base
.length
= sizeof(e
->event
);
1603 e
->event
.user_data
= vblwait
->request
.signal
;
1604 e
->base
.event
= &e
->event
.base
;
1605 e
->base
.file_priv
= file_priv
;
1606 e
->base
.destroy
= (void (*) (struct drm_pending_event
*)) kfree
;
1608 spin_lock_irqsave(&dev
->event_lock
, flags
);
1611 * drm_vblank_off() might have been called after we called
1612 * drm_vblank_get(). drm_vblank_off() holds event_lock
1613 * around the vblank disable, so no need for further locking.
1614 * The reference from drm_vblank_get() protects against
1615 * vblank disable from another source.
1617 if (!vblank
->enabled
) {
1622 if (file_priv
->event_space
< sizeof(e
->event
)) {
1627 file_priv
->event_space
-= sizeof(e
->event
);
1628 seq
= drm_vblank_count_and_time(dev
, pipe
, &now
);
1630 if ((vblwait
->request
.type
& _DRM_VBLANK_NEXTONMISS
) &&
1631 (seq
- vblwait
->request
.sequence
) <= (1 << 23)) {
1632 vblwait
->request
.sequence
= seq
+ 1;
1633 vblwait
->reply
.sequence
= vblwait
->request
.sequence
;
1636 DRM_DEBUG("event on vblank count %d, current %d, crtc %u\n",
1637 vblwait
->request
.sequence
, seq
, pipe
);
1639 trace_drm_vblank_event_queued(current
->pid
, pipe
,
1640 vblwait
->request
.sequence
);
1642 e
->event
.sequence
= vblwait
->request
.sequence
;
1643 if ((seq
- vblwait
->request
.sequence
) <= (1 << 23)) {
1644 drm_vblank_put(dev
, pipe
);
1645 send_vblank_event(dev
, e
, seq
, &now
);
1646 vblwait
->reply
.sequence
= seq
;
1648 /* drm_handle_vblank_events will call drm_vblank_put */
1649 list_add_tail(&e
->base
.link
, &dev
->vblank_event_list
);
1650 vblwait
->reply
.sequence
= vblwait
->request
.sequence
;
1653 spin_unlock_irqrestore(&dev
->event_lock
, flags
);
1658 spin_unlock_irqrestore(&dev
->event_lock
, flags
);
1661 drm_vblank_put(dev
, pipe
);
1668 * \param inode device inode.
1669 * \param file_priv DRM file private.
1670 * \param cmd command.
1671 * \param data user argument, pointing to a drm_wait_vblank structure.
1672 * \return zero on success or a negative number on failure.
1674 * This function enables the vblank interrupt on the pipe requested, then
1675 * sleeps waiting for the requested sequence number to occur, and drops
1676 * the vblank interrupt refcount afterwards. (vblank IRQ disable follows that
1677 * after a timeout with no further vblank waits scheduled).
1679 int drm_wait_vblank(struct drm_device
*dev
, void *data
,
1680 struct drm_file
*file_priv
)
1682 struct drm_vblank_crtc
*vblank
;
1683 union drm_wait_vblank
*vblwait
= data
;
1685 unsigned int flags
, seq
, pipe
, high_pipe
;
1687 if (!dev
->irq_enabled
)
1690 if (vblwait
->request
.type
& _DRM_VBLANK_SIGNAL
)
1693 if (vblwait
->request
.type
&
1694 ~(_DRM_VBLANK_TYPES_MASK
| _DRM_VBLANK_FLAGS_MASK
|
1695 _DRM_VBLANK_HIGH_CRTC_MASK
)) {
1696 DRM_ERROR("Unsupported type value 0x%x, supported mask 0x%x\n",
1697 vblwait
->request
.type
,
1698 (_DRM_VBLANK_TYPES_MASK
| _DRM_VBLANK_FLAGS_MASK
|
1699 _DRM_VBLANK_HIGH_CRTC_MASK
));
1703 flags
= vblwait
->request
.type
& _DRM_VBLANK_FLAGS_MASK
;
1704 high_pipe
= (vblwait
->request
.type
& _DRM_VBLANK_HIGH_CRTC_MASK
);
1706 pipe
= high_pipe
>> _DRM_VBLANK_HIGH_CRTC_SHIFT
;
1708 pipe
= flags
& _DRM_VBLANK_SECONDARY
? 1 : 0;
1709 if (pipe
>= dev
->num_crtcs
)
1712 vblank
= &dev
->vblank
[pipe
];
1714 ret
= drm_vblank_get(dev
, pipe
);
1716 DRM_DEBUG("failed to acquire vblank counter, %d\n", ret
);
1719 seq
= drm_vblank_count(dev
, pipe
);
1721 switch (vblwait
->request
.type
& _DRM_VBLANK_TYPES_MASK
) {
1722 case _DRM_VBLANK_RELATIVE
:
1723 vblwait
->request
.sequence
+= seq
;
1724 vblwait
->request
.type
&= ~_DRM_VBLANK_RELATIVE
;
1725 case _DRM_VBLANK_ABSOLUTE
:
1732 if (flags
& _DRM_VBLANK_EVENT
) {
1733 /* must hold on to the vblank ref until the event fires
1734 * drm_vblank_put will be called asynchronously
1736 return drm_queue_vblank_event(dev
, pipe
, vblwait
, file_priv
);
1739 if ((flags
& _DRM_VBLANK_NEXTONMISS
) &&
1740 (seq
- vblwait
->request
.sequence
) <= (1<<23)) {
1741 vblwait
->request
.sequence
= seq
+ 1;
1744 DRM_DEBUG("waiting on vblank count %d, crtc %u\n",
1745 vblwait
->request
.sequence
, pipe
);
1746 vblank
->last_wait
= vblwait
->request
.sequence
;
1747 DRM_WAIT_ON(ret
, vblank
->queue
, 3 * HZ
,
1748 (((drm_vblank_count(dev
, pipe
) -
1749 vblwait
->request
.sequence
) <= (1 << 23)) ||
1751 !dev
->irq_enabled
));
1753 if (ret
!= -EINTR
) {
1756 vblwait
->reply
.sequence
= drm_vblank_count_and_time(dev
, pipe
, &now
);
1757 vblwait
->reply
.tval_sec
= now
.tv_sec
;
1758 vblwait
->reply
.tval_usec
= now
.tv_usec
;
1760 DRM_DEBUG("returning %d to client\n",
1761 vblwait
->reply
.sequence
);
1763 DRM_DEBUG("vblank wait interrupted by signal\n");
1767 drm_vblank_put(dev
, pipe
);
1771 static void drm_handle_vblank_events(struct drm_device
*dev
, unsigned int pipe
)
1773 struct drm_pending_vblank_event
*e
, *t
;
1777 assert_spin_locked(&dev
->event_lock
);
1779 seq
= drm_vblank_count_and_time(dev
, pipe
, &now
);
1781 list_for_each_entry_safe(e
, t
, &dev
->vblank_event_list
, base
.link
) {
1782 if (e
->pipe
!= pipe
)
1784 if ((seq
- e
->event
.sequence
) > (1<<23))
1787 DRM_DEBUG("vblank event on %d, current %d\n",
1788 e
->event
.sequence
, seq
);
1790 list_del(&e
->base
.link
);
1791 drm_vblank_put(dev
, pipe
);
1792 send_vblank_event(dev
, e
, seq
, &now
);
1795 trace_drm_vblank_event(pipe
, seq
);
1799 * drm_handle_vblank - handle a vblank event
1801 * @pipe: index of CRTC where this event occurred
1803 * Drivers should call this routine in their vblank interrupt handlers to
1804 * update the vblank counter and send any signals that may be pending.
1806 * This is the legacy version of drm_crtc_handle_vblank().
1808 bool drm_handle_vblank(struct drm_device
*dev
, unsigned int pipe
)
1810 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1811 unsigned long irqflags
;
1813 if (WARN_ON_ONCE(!dev
->num_crtcs
))
1816 if (WARN_ON(pipe
>= dev
->num_crtcs
))
1819 spin_lock_irqsave(&dev
->event_lock
, irqflags
);
1821 /* Need timestamp lock to prevent concurrent execution with
1822 * vblank enable/disable, as this would cause inconsistent
1823 * or corrupted timestamps and vblank counts.
1825 spin_lock(&dev
->vblank_time_lock
);
1827 /* Vblank irq handling disabled. Nothing to do. */
1828 if (!vblank
->enabled
) {
1829 spin_unlock(&dev
->vblank_time_lock
);
1830 spin_unlock_irqrestore(&dev
->event_lock
, irqflags
);
1834 drm_update_vblank_count(dev
, pipe
, DRM_CALLED_FROM_VBLIRQ
);
1836 spin_unlock(&dev
->vblank_time_lock
);
1838 wake_up(&vblank
->queue
);
1839 drm_handle_vblank_events(dev
, pipe
);
1841 spin_unlock_irqrestore(&dev
->event_lock
, irqflags
);
1845 EXPORT_SYMBOL(drm_handle_vblank
);
1848 * drm_crtc_handle_vblank - handle a vblank event
1849 * @crtc: where this event occurred
1851 * Drivers should call this routine in their vblank interrupt handlers to
1852 * update the vblank counter and send any signals that may be pending.
1854 * This is the native KMS version of drm_handle_vblank().
1857 * True if the event was successfully handled, false on failure.
1859 bool drm_crtc_handle_vblank(struct drm_crtc
*crtc
)
1861 return drm_handle_vblank(crtc
->dev
, drm_crtc_index(crtc
));
1863 EXPORT_SYMBOL(drm_crtc_handle_vblank
);
1866 * drm_vblank_no_hw_counter - "No hw counter" implementation of .get_vblank_counter()
1868 * @pipe: CRTC for which to read the counter
1870 * Drivers can plug this into the .get_vblank_counter() function if
1871 * there is no useable hardware frame counter available.
1876 u32
drm_vblank_no_hw_counter(struct drm_device
*dev
, unsigned int pipe
)
1880 EXPORT_SYMBOL(drm_vblank_no_hw_counter
);