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
, int crtc
,
79 struct timeval
*t_vblank
)
81 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[crtc
];
84 assert_spin_locked(&dev
->vblank_time_lock
);
87 /* All writers hold the spinlock, but readers are serialized by
88 * the latching of vblank->count below.
90 tslot
= vblank
->count
+ vblank_count_inc
;
91 vblanktimestamp(dev
, crtc
, tslot
) = *t_vblank
;
95 * vblank timestamp updates are protected on the write side with
96 * vblank_time_lock, but on the read side done locklessly using a
97 * sequence-lock on the vblank counter. Ensure correct ordering using
98 * memory barrriers. We need the barrier both before and also after the
99 * counter update to synchronize with the next timestamp write.
100 * The read-side barriers for this are in drm_vblank_count_and_time.
103 vblank
->count
+= vblank_count_inc
;
108 * drm_update_vblank_count - update the master vblank counter
110 * @pipe: counter to update
112 * Call back into the driver to update the appropriate vblank counter
113 * (specified by @crtc). Deal with wraparound, if it occurred, and
114 * update the last read value so we can deal with wraparound on the next
117 * Only necessary when going from off->on, to account for frames we
118 * didn't get an interrupt for.
120 * Note: caller must hold dev->vbl_lock since this reads & writes
121 * device vblank fields.
123 static void drm_update_vblank_count(struct drm_device
*dev
, unsigned int pipe
)
125 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
126 u32 cur_vblank
, diff
;
128 struct timeval t_vblank
;
131 * Interrupts were disabled prior to this call, so deal with counter
133 * NOTE! It's possible we lost a full dev->max_vblank_count + 1 events
134 * here if the register is small or we had vblank interrupts off for
137 * We repeat the hardware vblank counter & timestamp query until
138 * we get consistent results. This to prevent races between gpu
139 * updating its hardware counter while we are retrieving the
140 * corresponding vblank timestamp.
143 cur_vblank
= dev
->driver
->get_vblank_counter(dev
, pipe
);
144 rc
= drm_get_last_vbltimestamp(dev
, pipe
, &t_vblank
, 0);
145 } while (cur_vblank
!= dev
->driver
->get_vblank_counter(dev
, pipe
));
147 /* Deal with counter wrap */
148 diff
= cur_vblank
- vblank
->last
;
149 if (cur_vblank
< vblank
->last
) {
150 diff
+= dev
->max_vblank_count
+ 1;
152 DRM_DEBUG("last_vblank[%u]=0x%x, cur_vblank=0x%x => diff=0x%x\n",
153 pipe
, vblank
->last
, cur_vblank
, diff
);
156 DRM_DEBUG("updating vblank count on crtc %u, missed %d\n",
163 * Only reinitialize corresponding vblank timestamp if high-precision query
164 * available and didn't fail. Otherwise reinitialize delayed at next vblank
165 * interrupt and assign 0 for now, to mark the vblanktimestamp as invalid.
168 t_vblank
= (struct timeval
) {0, 0};
170 store_vblank(dev
, pipe
, diff
, &t_vblank
);
174 * Disable vblank irq's on crtc, make sure that last vblank count
175 * of hardware and corresponding consistent software vblank counter
176 * are preserved, even if there are any spurious vblank irq's after
179 static void vblank_disable_and_save(struct drm_device
*dev
, unsigned int pipe
)
181 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
182 unsigned long irqflags
;
186 struct timeval tvblank
;
187 int count
= DRM_TIMESTAMP_MAXRETRIES
;
189 /* Prevent vblank irq processing while disabling vblank irqs,
190 * so no updates of timestamps or count can happen after we've
191 * disabled. Needed to prevent races in case of delayed irq's.
193 spin_lock_irqsave(&dev
->vblank_time_lock
, irqflags
);
196 * If the vblank interrupt was already disabled update the count
197 * and timestamp to maintain the appearance that the counter
198 * has been ticking all along until this time. This makes the
199 * count account for the entire time between drm_vblank_on() and
202 * But only do this if precise vblank timestamps are available.
203 * Otherwise we might read a totally bogus timestamp since drivers
204 * lacking precise timestamp support rely upon sampling the system clock
205 * at vblank interrupt time. Which obviously won't work out well if the
206 * vblank interrupt is disabled.
208 if (!vblank
->enabled
&&
209 drm_get_last_vbltimestamp(dev
, pipe
, &tvblank
, 0)) {
210 drm_update_vblank_count(dev
, pipe
);
211 spin_unlock_irqrestore(&dev
->vblank_time_lock
, irqflags
);
216 * Only disable vblank interrupts if they're enabled. This avoids
217 * calling the ->disable_vblank() operation in atomic context with the
218 * hardware potentially runtime suspended.
220 if (vblank
->enabled
) {
221 dev
->driver
->disable_vblank(dev
, pipe
);
222 vblank
->enabled
= false;
225 /* No further vblank irq's will be processed after
226 * this point. Get current hardware vblank count and
227 * vblank timestamp, repeat until they are consistent.
229 * FIXME: There is still a race condition here and in
230 * drm_update_vblank_count() which can cause off-by-one
231 * reinitialization of software vblank counter. If gpu
232 * vblank counter doesn't increment exactly at the leading
233 * edge of a vblank interval, then we can lose 1 count if
234 * we happen to execute between start of vblank and the
235 * delayed gpu counter increment.
238 vblank
->last
= dev
->driver
->get_vblank_counter(dev
, pipe
);
239 vblrc
= drm_get_last_vbltimestamp(dev
, pipe
, &tvblank
, 0);
240 } while (vblank
->last
!= dev
->driver
->get_vblank_counter(dev
, pipe
) && (--count
) && vblrc
);
245 /* Compute time difference to stored timestamp of last vblank
246 * as updated by last invocation of drm_handle_vblank() in vblank irq.
248 vblcount
= vblank
->count
;
249 diff_ns
= timeval_to_ns(&tvblank
) -
250 timeval_to_ns(&vblanktimestamp(dev
, pipe
, vblcount
));
252 /* If there is at least 1 msec difference between the last stored
253 * timestamp and tvblank, then we are currently executing our
254 * disable inside a new vblank interval, the tvblank timestamp
255 * corresponds to this new vblank interval and the irq handler
256 * for this vblank didn't run yet and won't run due to our disable.
257 * Therefore we need to do the job of drm_handle_vblank() and
258 * increment the vblank counter by one to account for this vblank.
260 * Skip this step if there isn't any high precision timestamp
261 * available. In that case we can't account for this and just
264 if (vblrc
&& (abs64(diff_ns
) > 1000000))
265 store_vblank(dev
, pipe
, 1, &tvblank
);
267 spin_unlock_irqrestore(&dev
->vblank_time_lock
, irqflags
);
270 static void vblank_disable_fn(unsigned long arg
)
272 struct drm_vblank_crtc
*vblank
= (void *)arg
;
273 struct drm_device
*dev
= vblank
->dev
;
274 unsigned int pipe
= vblank
->pipe
;
275 unsigned long irqflags
;
277 if (!dev
->vblank_disable_allowed
)
280 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
281 if (atomic_read(&vblank
->refcount
) == 0 && vblank
->enabled
) {
282 DRM_DEBUG("disabling vblank on crtc %u\n", pipe
);
283 vblank_disable_and_save(dev
, pipe
);
285 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
289 * drm_vblank_cleanup - cleanup vblank support
292 * This function cleans up any resources allocated in drm_vblank_init.
294 void drm_vblank_cleanup(struct drm_device
*dev
)
298 /* Bail if the driver didn't call drm_vblank_init() */
299 if (dev
->num_crtcs
== 0)
302 for (pipe
= 0; pipe
< dev
->num_crtcs
; pipe
++) {
303 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
305 WARN_ON(vblank
->enabled
&&
306 drm_core_check_feature(dev
, DRIVER_MODESET
));
308 del_timer_sync(&vblank
->disable_timer
);
315 EXPORT_SYMBOL(drm_vblank_cleanup
);
318 * drm_vblank_init - initialize vblank support
320 * @num_crtcs: number of CRTCs supported by @dev
322 * This function initializes vblank support for @num_crtcs display pipelines.
325 * Zero on success or a negative error code on failure.
327 int drm_vblank_init(struct drm_device
*dev
, unsigned int num_crtcs
)
332 spin_lock_init(&dev
->vbl_lock
);
333 spin_lock_init(&dev
->vblank_time_lock
);
335 dev
->num_crtcs
= num_crtcs
;
337 dev
->vblank
= kcalloc(num_crtcs
, sizeof(*dev
->vblank
), GFP_KERNEL
);
341 for (i
= 0; i
< num_crtcs
; i
++) {
342 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[i
];
346 init_waitqueue_head(&vblank
->queue
);
347 setup_timer(&vblank
->disable_timer
, vblank_disable_fn
,
348 (unsigned long)vblank
);
351 DRM_INFO("Supports vblank timestamp caching Rev 2 (21.10.2013).\n");
353 /* Driver specific high-precision vblank timestamping supported? */
354 if (dev
->driver
->get_vblank_timestamp
)
355 DRM_INFO("Driver supports precise vblank timestamp query.\n");
357 DRM_INFO("No driver support for vblank timestamp query.\n");
359 /* Must have precise timestamping for reliable vblank instant disable */
360 if (dev
->vblank_disable_immediate
&& !dev
->driver
->get_vblank_timestamp
) {
361 dev
->vblank_disable_immediate
= false;
362 DRM_INFO("Setting vblank_disable_immediate to false because "
363 "get_vblank_timestamp == NULL\n");
366 dev
->vblank_disable_allowed
= false;
374 EXPORT_SYMBOL(drm_vblank_init
);
376 static void drm_irq_vgaarb_nokms(void *cookie
, bool state
)
378 struct drm_device
*dev
= cookie
;
380 if (dev
->driver
->vgaarb_irq
) {
381 dev
->driver
->vgaarb_irq(dev
, state
);
385 if (!dev
->irq_enabled
)
389 if (dev
->driver
->irq_uninstall
)
390 dev
->driver
->irq_uninstall(dev
);
392 if (dev
->driver
->irq_preinstall
)
393 dev
->driver
->irq_preinstall(dev
);
394 if (dev
->driver
->irq_postinstall
)
395 dev
->driver
->irq_postinstall(dev
);
400 * drm_irq_install - install IRQ handler
402 * @irq: IRQ number to install the handler for
404 * Initializes the IRQ related data. Installs the handler, calling the driver
405 * irq_preinstall() and irq_postinstall() functions before and after the
408 * This is the simplified helper interface provided for drivers with no special
409 * needs. Drivers which need to install interrupt handlers for multiple
410 * interrupts must instead set drm_device->irq_enabled to signal the DRM core
411 * that vblank interrupts are available.
414 * Zero on success or a negative error code on failure.
416 int drm_irq_install(struct drm_device
*dev
, int irq
)
419 unsigned long sh_flags
= 0;
421 if (!drm_core_check_feature(dev
, DRIVER_HAVE_IRQ
))
427 /* Driver must have been initialized */
428 if (!dev
->dev_private
)
431 if (dev
->irq_enabled
)
433 dev
->irq_enabled
= true;
435 DRM_DEBUG("irq=%d\n", irq
);
437 /* Before installing handler */
438 if (dev
->driver
->irq_preinstall
)
439 dev
->driver
->irq_preinstall(dev
);
441 /* Install handler */
442 if (drm_core_check_feature(dev
, DRIVER_IRQ_SHARED
))
443 sh_flags
= IRQF_SHARED
;
445 ret
= request_irq(irq
, dev
->driver
->irq_handler
,
446 sh_flags
, dev
->driver
->name
, dev
);
449 dev
->irq_enabled
= false;
453 if (!drm_core_check_feature(dev
, DRIVER_MODESET
))
454 vga_client_register(dev
->pdev
, (void *)dev
, drm_irq_vgaarb_nokms
, NULL
);
456 /* After installing handler */
457 if (dev
->driver
->irq_postinstall
)
458 ret
= dev
->driver
->irq_postinstall(dev
);
461 dev
->irq_enabled
= false;
462 if (!drm_core_check_feature(dev
, DRIVER_MODESET
))
463 vga_client_register(dev
->pdev
, NULL
, NULL
, NULL
);
471 EXPORT_SYMBOL(drm_irq_install
);
474 * drm_irq_uninstall - uninstall the IRQ handler
477 * Calls the driver's irq_uninstall() function and unregisters the IRQ handler.
478 * This should only be called by drivers which used drm_irq_install() to set up
479 * their interrupt handler. Other drivers must only reset
480 * drm_device->irq_enabled to false.
482 * Note that for kernel modesetting drivers it is a bug if this function fails.
483 * The sanity checks are only to catch buggy user modesetting drivers which call
484 * the same function through an ioctl.
487 * Zero on success or a negative error code on failure.
489 int drm_irq_uninstall(struct drm_device
*dev
)
491 unsigned long irqflags
;
495 if (!drm_core_check_feature(dev
, DRIVER_HAVE_IRQ
))
498 irq_enabled
= dev
->irq_enabled
;
499 dev
->irq_enabled
= false;
502 * Wake up any waiters so they don't hang. This is just to paper over
503 * isssues for UMS drivers which aren't in full control of their
504 * vblank/irq handling. KMS drivers must ensure that vblanks are all
505 * disabled when uninstalling the irq handler.
507 if (dev
->num_crtcs
) {
508 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
509 for (i
= 0; i
< dev
->num_crtcs
; i
++) {
510 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[i
];
512 if (!vblank
->enabled
)
515 WARN_ON(drm_core_check_feature(dev
, DRIVER_MODESET
));
517 vblank_disable_and_save(dev
, i
);
518 wake_up(&vblank
->queue
);
520 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
526 DRM_DEBUG("irq=%d\n", dev
->irq
);
528 if (!drm_core_check_feature(dev
, DRIVER_MODESET
))
529 vga_client_register(dev
->pdev
, NULL
, NULL
, NULL
);
531 if (dev
->driver
->irq_uninstall
)
532 dev
->driver
->irq_uninstall(dev
);
534 free_irq(dev
->irq
, dev
);
538 EXPORT_SYMBOL(drm_irq_uninstall
);
543 * \param inode device inode.
544 * \param file_priv DRM file private.
545 * \param cmd command.
546 * \param arg user argument, pointing to a drm_control structure.
547 * \return zero on success or a negative number on failure.
549 * Calls irq_install() or irq_uninstall() according to \p arg.
551 int drm_control(struct drm_device
*dev
, void *data
,
552 struct drm_file
*file_priv
)
554 struct drm_control
*ctl
= data
;
557 /* if we haven't irq we fallback for compatibility reasons -
558 * this used to be a separate function in drm_dma.h
561 if (!drm_core_check_feature(dev
, DRIVER_HAVE_IRQ
))
563 if (drm_core_check_feature(dev
, DRIVER_MODESET
))
565 /* UMS was only ever support on pci devices. */
566 if (WARN_ON(!dev
->pdev
))
570 case DRM_INST_HANDLER
:
571 irq
= dev
->pdev
->irq
;
573 if (dev
->if_version
< DRM_IF_VERSION(1, 2) &&
576 mutex_lock(&dev
->struct_mutex
);
577 ret
= drm_irq_install(dev
, irq
);
578 mutex_unlock(&dev
->struct_mutex
);
581 case DRM_UNINST_HANDLER
:
582 mutex_lock(&dev
->struct_mutex
);
583 ret
= drm_irq_uninstall(dev
);
584 mutex_unlock(&dev
->struct_mutex
);
593 * drm_calc_timestamping_constants - calculate vblank timestamp constants
594 * @crtc: drm_crtc whose timestamp constants should be updated.
595 * @mode: display mode containing the scanout timings
597 * Calculate and store various constants which are later
598 * needed by vblank and swap-completion timestamping, e.g,
599 * by drm_calc_vbltimestamp_from_scanoutpos(). They are
600 * derived from CRTC's true scanout timing, so they take
601 * things like panel scaling or other adjustments into account.
603 void drm_calc_timestamping_constants(struct drm_crtc
*crtc
,
604 const struct drm_display_mode
*mode
)
606 int linedur_ns
= 0, pixeldur_ns
= 0, framedur_ns
= 0;
607 int dotclock
= mode
->crtc_clock
;
609 /* Valid dotclock? */
611 int frame_size
= mode
->crtc_htotal
* mode
->crtc_vtotal
;
614 * Convert scanline length in pixels and video
615 * dot clock to line duration, frame duration
616 * and pixel duration in nanoseconds:
618 pixeldur_ns
= 1000000 / dotclock
;
619 linedur_ns
= div_u64((u64
) mode
->crtc_htotal
* 1000000, dotclock
);
620 framedur_ns
= div_u64((u64
) frame_size
* 1000000, dotclock
);
623 * Fields of interlaced scanout modes are only half a frame duration.
625 if (mode
->flags
& DRM_MODE_FLAG_INTERLACE
)
628 DRM_ERROR("crtc %u: Can't calculate constants, dotclock = 0!\n",
631 crtc
->pixeldur_ns
= pixeldur_ns
;
632 crtc
->linedur_ns
= linedur_ns
;
633 crtc
->framedur_ns
= framedur_ns
;
635 DRM_DEBUG("crtc %u: hwmode: htotal %d, vtotal %d, vdisplay %d\n",
636 crtc
->base
.id
, mode
->crtc_htotal
,
637 mode
->crtc_vtotal
, mode
->crtc_vdisplay
);
638 DRM_DEBUG("crtc %u: clock %d kHz framedur %d linedur %d, pixeldur %d\n",
639 crtc
->base
.id
, dotclock
, framedur_ns
,
640 linedur_ns
, pixeldur_ns
);
642 EXPORT_SYMBOL(drm_calc_timestamping_constants
);
645 * drm_calc_vbltimestamp_from_scanoutpos - precise vblank timestamp helper
647 * @pipe: index of CRTC whose vblank timestamp to retrieve
648 * @max_error: Desired maximum allowable error in timestamps (nanosecs)
649 * On return contains true maximum error of timestamp
650 * @vblank_time: Pointer to struct timeval which should receive the timestamp
651 * @flags: Flags to pass to driver:
653 * DRM_CALLED_FROM_VBLIRQ = If function is called from vbl IRQ handler
654 * @refcrtc: CRTC which defines scanout timing
655 * @mode: mode which defines the scanout timings
657 * Implements calculation of exact vblank timestamps from given drm_display_mode
658 * timings and current video scanout position of a CRTC. This can be called from
659 * within get_vblank_timestamp() implementation of a kms driver to implement the
660 * actual timestamping.
662 * Should return timestamps conforming to the OML_sync_control OpenML
663 * extension specification. The timestamp corresponds to the end of
664 * the vblank interval, aka start of scanout of topmost-leftmost display
665 * pixel in the following video frame.
667 * Requires support for optional dev->driver->get_scanout_position()
668 * in kms driver, plus a bit of setup code to provide a drm_display_mode
669 * that corresponds to the true scanout timing.
671 * The current implementation only handles standard video modes. It
672 * returns as no operation if a doublescan or interlaced video mode is
673 * active. Higher level code is expected to handle this.
676 * Negative value on error, failure or if not supported in current
679 * -EINVAL - Invalid CRTC.
680 * -EAGAIN - Temporary unavailable, e.g., called before initial modeset.
681 * -ENOTSUPP - Function not supported in current display mode.
682 * -EIO - Failed, e.g., due to failed scanout position query.
684 * Returns or'ed positive status flags on success:
686 * DRM_VBLANKTIME_SCANOUTPOS_METHOD - Signal this method used for timestamping.
687 * DRM_VBLANKTIME_INVBL - Timestamp taken while scanout was in vblank interval.
690 int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device
*dev
,
693 struct timeval
*vblank_time
,
695 const struct drm_crtc
*refcrtc
,
696 const struct drm_display_mode
*mode
)
698 struct timeval tv_etime
;
699 ktime_t stime
, etime
;
702 int framedur_ns
, linedur_ns
, pixeldur_ns
, delta_ns
, duration_ns
;
705 if (pipe
>= dev
->num_crtcs
) {
706 DRM_ERROR("Invalid crtc %u\n", pipe
);
710 /* Scanout position query not supported? Should not happen. */
711 if (!dev
->driver
->get_scanout_position
) {
712 DRM_ERROR("Called from driver w/o get_scanout_position()!?\n");
716 /* Durations of frames, lines, pixels in nanoseconds. */
717 framedur_ns
= refcrtc
->framedur_ns
;
718 linedur_ns
= refcrtc
->linedur_ns
;
719 pixeldur_ns
= refcrtc
->pixeldur_ns
;
721 /* If mode timing undefined, just return as no-op:
722 * Happens during initial modesetting of a crtc.
724 if (framedur_ns
== 0) {
725 DRM_DEBUG("crtc %u: Noop due to uninitialized mode.\n", pipe
);
729 /* Get current scanout position with system timestamp.
730 * Repeat query up to DRM_TIMESTAMP_MAXRETRIES times
731 * if single query takes longer than max_error nanoseconds.
733 * This guarantees a tight bound on maximum error if
734 * code gets preempted or delayed for some reason.
736 for (i
= 0; i
< DRM_TIMESTAMP_MAXRETRIES
; i
++) {
738 * Get vertical and horizontal scanout position vpos, hpos,
739 * and bounding timestamps stime, etime, pre/post query.
741 vbl_status
= dev
->driver
->get_scanout_position(dev
, pipe
, flags
, &vpos
,
742 &hpos
, &stime
, &etime
);
744 /* Return as no-op if scanout query unsupported or failed. */
745 if (!(vbl_status
& DRM_SCANOUTPOS_VALID
)) {
746 DRM_DEBUG("crtc %u : scanoutpos query failed [%d].\n",
751 /* Compute uncertainty in timestamp of scanout position query. */
752 duration_ns
= ktime_to_ns(etime
) - ktime_to_ns(stime
);
754 /* Accept result with < max_error nsecs timing uncertainty. */
755 if (duration_ns
<= *max_error
)
759 /* Noisy system timing? */
760 if (i
== DRM_TIMESTAMP_MAXRETRIES
) {
761 DRM_DEBUG("crtc %u: Noisy timestamp %d us > %d us [%d reps].\n",
762 pipe
, duration_ns
/1000, *max_error
/1000, i
);
765 /* Return upper bound of timestamp precision error. */
766 *max_error
= duration_ns
;
768 /* Check if in vblank area:
769 * vpos is >=0 in video scanout area, but negative
770 * within vblank area, counting down the number of lines until
773 invbl
= vbl_status
& DRM_SCANOUTPOS_IN_VBLANK
;
775 /* Convert scanout position into elapsed time at raw_time query
776 * since start of scanout at first display scanline. delta_ns
777 * can be negative if start of scanout hasn't happened yet.
779 delta_ns
= vpos
* linedur_ns
+ hpos
* pixeldur_ns
;
781 if (!drm_timestamp_monotonic
)
782 etime
= ktime_mono_to_real(etime
);
784 /* save this only for debugging purposes */
785 tv_etime
= ktime_to_timeval(etime
);
786 /* Subtract time delta from raw timestamp to get final
787 * vblank_time timestamp for end of vblank.
790 etime
= ktime_add_ns(etime
, -delta_ns
);
792 etime
= ktime_sub_ns(etime
, delta_ns
);
793 *vblank_time
= ktime_to_timeval(etime
);
795 DRM_DEBUG("crtc %u : v %d p(%d,%d)@ %ld.%ld -> %ld.%ld [e %d us, %d rep]\n",
796 pipe
, (int)vbl_status
, hpos
, vpos
,
797 (long)tv_etime
.tv_sec
, (long)tv_etime
.tv_usec
,
798 (long)vblank_time
->tv_sec
, (long)vblank_time
->tv_usec
,
799 duration_ns
/1000, i
);
801 vbl_status
= DRM_VBLANKTIME_SCANOUTPOS_METHOD
;
803 vbl_status
|= DRM_VBLANKTIME_IN_VBLANK
;
807 EXPORT_SYMBOL(drm_calc_vbltimestamp_from_scanoutpos
);
809 static struct timeval
get_drm_timestamp(void)
813 now
= drm_timestamp_monotonic
? ktime_get() : ktime_get_real();
814 return ktime_to_timeval(now
);
818 * drm_get_last_vbltimestamp - retrieve raw timestamp for the most recent
821 * @pipe: index of CRTC whose vblank timestamp to retrieve
822 * @tvblank: Pointer to target struct timeval which should receive the timestamp
823 * @flags: Flags to pass to driver:
825 * DRM_CALLED_FROM_VBLIRQ = If function is called from vbl IRQ handler
827 * Fetches the system timestamp corresponding to the time of the most recent
828 * vblank interval on specified CRTC. May call into kms-driver to
829 * compute the timestamp with a high-precision GPU specific method.
831 * Returns zero if timestamp originates from uncorrected do_gettimeofday()
832 * call, i.e., it isn't very precisely locked to the true vblank.
835 * True if timestamp is considered to be very precise, false otherwise.
838 drm_get_last_vbltimestamp(struct drm_device
*dev
, unsigned int pipe
,
839 struct timeval
*tvblank
, unsigned flags
)
843 /* Define requested maximum error on timestamps (nanoseconds). */
844 int max_error
= (int) drm_timestamp_precision
* 1000;
846 /* Query driver if possible and precision timestamping enabled. */
847 if (dev
->driver
->get_vblank_timestamp
&& (max_error
> 0)) {
848 ret
= dev
->driver
->get_vblank_timestamp(dev
, pipe
, &max_error
,
854 /* GPU high precision timestamp query unsupported or failed.
855 * Return current monotonic/gettimeofday timestamp as best estimate.
857 *tvblank
= get_drm_timestamp();
863 * drm_vblank_count - retrieve "cooked" vblank counter value
865 * @pipe: index of CRTC for which to retrieve the counter
867 * Fetches the "cooked" vblank count value that represents the number of
868 * vblank events since the system was booted, including lost events due to
869 * modesetting activity.
871 * This is the legacy version of drm_crtc_vblank_count().
874 * The software vblank counter.
876 u32
drm_vblank_count(struct drm_device
*dev
, int pipe
)
878 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
880 if (WARN_ON(pipe
>= dev
->num_crtcs
))
883 return vblank
->count
;
885 EXPORT_SYMBOL(drm_vblank_count
);
888 * drm_crtc_vblank_count - retrieve "cooked" vblank counter value
889 * @crtc: which counter to retrieve
891 * Fetches the "cooked" vblank count value that represents the number of
892 * vblank events since the system was booted, including lost events due to
893 * modesetting activity.
895 * This is the native KMS version of drm_vblank_count().
898 * The software vblank counter.
900 u32
drm_crtc_vblank_count(struct drm_crtc
*crtc
)
902 return drm_vblank_count(crtc
->dev
, drm_crtc_index(crtc
));
904 EXPORT_SYMBOL(drm_crtc_vblank_count
);
907 * drm_vblank_count_and_time - retrieve "cooked" vblank counter value and the
908 * system timestamp corresponding to that vblank counter value.
910 * @pipe: index of CRTC whose counter to retrieve
911 * @vblanktime: Pointer to struct timeval to receive the vblank timestamp.
913 * Fetches the "cooked" vblank count value that represents the number of
914 * vblank events since the system was booted, including lost events due to
915 * modesetting activity. Returns corresponding system timestamp of the time
916 * of the vblank interval that corresponds to the current vblank counter value.
918 u32
drm_vblank_count_and_time(struct drm_device
*dev
, unsigned int pipe
,
919 struct timeval
*vblanktime
)
921 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
924 if (WARN_ON(pipe
>= dev
->num_crtcs
))
928 * Vblank timestamps are read lockless. To ensure consistency the vblank
929 * counter is rechecked and ordering is ensured using memory barriers.
930 * This works like a seqlock. The write-side barriers are in store_vblank.
933 cur_vblank
= vblank
->count
;
935 *vblanktime
= vblanktimestamp(dev
, pipe
, cur_vblank
);
937 } while (cur_vblank
!= vblank
->count
);
941 EXPORT_SYMBOL(drm_vblank_count_and_time
);
943 static void send_vblank_event(struct drm_device
*dev
,
944 struct drm_pending_vblank_event
*e
,
945 unsigned long seq
, struct timeval
*now
)
947 WARN_ON_SMP(!spin_is_locked(&dev
->event_lock
));
948 e
->event
.sequence
= seq
;
949 e
->event
.tv_sec
= now
->tv_sec
;
950 e
->event
.tv_usec
= now
->tv_usec
;
952 list_add_tail(&e
->base
.link
,
953 &e
->base
.file_priv
->event_list
);
954 wake_up_interruptible(&e
->base
.file_priv
->event_wait
);
955 trace_drm_vblank_event_delivered(e
->base
.pid
, e
->pipe
,
960 * drm_send_vblank_event - helper to send vblank event after pageflip
963 * @e: the event to send
965 * Updates sequence # and timestamp on event, and sends it to userspace.
966 * Caller must hold event lock.
968 * This is the legacy version of drm_crtc_send_vblank_event().
970 void drm_send_vblank_event(struct drm_device
*dev
, unsigned int pipe
,
971 struct drm_pending_vblank_event
*e
)
976 if (dev
->num_crtcs
> 0) {
977 seq
= drm_vblank_count_and_time(dev
, pipe
, &now
);
981 now
= get_drm_timestamp();
984 send_vblank_event(dev
, e
, seq
, &now
);
986 EXPORT_SYMBOL(drm_send_vblank_event
);
989 * drm_crtc_send_vblank_event - helper to send vblank event after pageflip
990 * @crtc: the source CRTC of the vblank event
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 native KMS version of drm_send_vblank_event().
998 void drm_crtc_send_vblank_event(struct drm_crtc
*crtc
,
999 struct drm_pending_vblank_event
*e
)
1001 drm_send_vblank_event(crtc
->dev
, drm_crtc_index(crtc
), e
);
1003 EXPORT_SYMBOL(drm_crtc_send_vblank_event
);
1006 * drm_vblank_enable - enable the vblank interrupt on a CRTC
1011 * Zero on success or a negative error code on failure.
1013 static int drm_vblank_enable(struct drm_device
*dev
, unsigned int pipe
)
1015 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1018 assert_spin_locked(&dev
->vbl_lock
);
1020 spin_lock(&dev
->vblank_time_lock
);
1022 if (!vblank
->enabled
) {
1024 * Enable vblank irqs under vblank_time_lock protection.
1025 * All vblank count & timestamp updates are held off
1026 * until we are done reinitializing master counter and
1027 * timestamps. Filtercode in drm_handle_vblank() will
1028 * prevent double-accounting of same vblank interval.
1030 ret
= dev
->driver
->enable_vblank(dev
, pipe
);
1031 DRM_DEBUG("enabling vblank on crtc %u, ret: %d\n", pipe
, ret
);
1033 atomic_dec(&vblank
->refcount
);
1035 vblank
->enabled
= true;
1036 drm_update_vblank_count(dev
, pipe
);
1040 spin_unlock(&dev
->vblank_time_lock
);
1046 * drm_vblank_get - get a reference count on vblank events
1048 * @pipe: index of CRTC to own
1050 * Acquire a reference count on vblank events to avoid having them disabled
1053 * This is the legacy version of drm_crtc_vblank_get().
1056 * Zero on success or a negative error code on failure.
1058 int drm_vblank_get(struct drm_device
*dev
, unsigned int pipe
)
1060 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1061 unsigned long irqflags
;
1064 if (!dev
->num_crtcs
)
1067 if (WARN_ON(pipe
>= dev
->num_crtcs
))
1070 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
1071 /* Going from 0->1 means we have to enable interrupts again */
1072 if (atomic_add_return(1, &vblank
->refcount
) == 1) {
1073 ret
= drm_vblank_enable(dev
, pipe
);
1075 if (!vblank
->enabled
) {
1076 atomic_dec(&vblank
->refcount
);
1080 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
1084 EXPORT_SYMBOL(drm_vblank_get
);
1087 * drm_crtc_vblank_get - get a reference count on vblank events
1088 * @crtc: which CRTC to own
1090 * Acquire a reference count on vblank events to avoid having them disabled
1093 * This is the native kms version of drm_vblank_get().
1096 * Zero on success or a negative error code on failure.
1098 int drm_crtc_vblank_get(struct drm_crtc
*crtc
)
1100 return drm_vblank_get(crtc
->dev
, drm_crtc_index(crtc
));
1102 EXPORT_SYMBOL(drm_crtc_vblank_get
);
1105 * drm_vblank_put - release ownership of vblank events
1107 * @pipe: index of CRTC to release
1109 * Release ownership of a given vblank counter, turning off interrupts
1110 * if possible. Disable interrupts after drm_vblank_offdelay milliseconds.
1112 * This is the legacy version of drm_crtc_vblank_put().
1114 void drm_vblank_put(struct drm_device
*dev
, unsigned int pipe
)
1116 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1118 if (WARN_ON(pipe
>= dev
->num_crtcs
))
1121 if (WARN_ON(atomic_read(&vblank
->refcount
) == 0))
1124 /* Last user schedules interrupt disable */
1125 if (atomic_dec_and_test(&vblank
->refcount
)) {
1126 if (drm_vblank_offdelay
== 0)
1128 else if (dev
->vblank_disable_immediate
|| drm_vblank_offdelay
< 0)
1129 vblank_disable_fn((unsigned long)vblank
);
1131 mod_timer(&vblank
->disable_timer
,
1132 jiffies
+ ((drm_vblank_offdelay
* HZ
)/1000));
1135 EXPORT_SYMBOL(drm_vblank_put
);
1138 * drm_crtc_vblank_put - give up ownership of vblank events
1139 * @crtc: which counter to give up
1141 * Release ownership of a given vblank counter, turning off interrupts
1142 * if possible. Disable interrupts after drm_vblank_offdelay milliseconds.
1144 * This is the native kms version of drm_vblank_put().
1146 void drm_crtc_vblank_put(struct drm_crtc
*crtc
)
1148 drm_vblank_put(crtc
->dev
, drm_crtc_index(crtc
));
1150 EXPORT_SYMBOL(drm_crtc_vblank_put
);
1153 * drm_wait_one_vblank - wait for one vblank
1157 * This waits for one vblank to pass on @crtc, using the irq driver interfaces.
1158 * It is a failure to call this when the vblank irq for @crtc is disabled, e.g.
1159 * due to lack of driver support or because the crtc is off.
1161 void drm_wait_one_vblank(struct drm_device
*dev
, unsigned int pipe
)
1163 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1167 if (WARN_ON(pipe
>= dev
->num_crtcs
))
1170 ret
= drm_vblank_get(dev
, pipe
);
1171 if (WARN(ret
, "vblank not available on crtc %i, ret=%i\n", pipe
, ret
))
1174 last
= drm_vblank_count(dev
, pipe
);
1176 ret
= wait_event_timeout(vblank
->queue
,
1177 last
!= drm_vblank_count(dev
, pipe
),
1178 msecs_to_jiffies(100));
1180 WARN(ret
== 0, "vblank wait timed out on crtc %i\n", pipe
);
1182 drm_vblank_put(dev
, pipe
);
1184 EXPORT_SYMBOL(drm_wait_one_vblank
);
1187 * drm_crtc_wait_one_vblank - wait for one vblank
1190 * This waits for one vblank to pass on @crtc, using the irq driver interfaces.
1191 * It is a failure to call this when the vblank irq for @crtc is disabled, e.g.
1192 * due to lack of driver support or because the crtc is off.
1194 void drm_crtc_wait_one_vblank(struct drm_crtc
*crtc
)
1196 drm_wait_one_vblank(crtc
->dev
, drm_crtc_index(crtc
));
1198 EXPORT_SYMBOL(drm_crtc_wait_one_vblank
);
1201 * drm_vblank_off - disable vblank events on a CRTC
1205 * Drivers can use this function to shut down the vblank interrupt handling when
1206 * disabling a crtc. This function ensures that the latest vblank frame count is
1207 * stored so that drm_vblank_on() can restore it again.
1209 * Drivers must use this function when the hardware vblank counter can get
1210 * reset, e.g. when suspending.
1212 * This is the legacy version of drm_crtc_vblank_off().
1214 void drm_vblank_off(struct drm_device
*dev
, unsigned int pipe
)
1216 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1217 struct drm_pending_vblank_event
*e
, *t
;
1219 unsigned long irqflags
;
1222 if (WARN_ON(pipe
>= dev
->num_crtcs
))
1225 spin_lock_irqsave(&dev
->event_lock
, irqflags
);
1227 spin_lock(&dev
->vbl_lock
);
1228 vblank_disable_and_save(dev
, pipe
);
1229 wake_up(&vblank
->queue
);
1232 * Prevent subsequent drm_vblank_get() from re-enabling
1233 * the vblank interrupt by bumping the refcount.
1235 if (!vblank
->inmodeset
) {
1236 atomic_inc(&vblank
->refcount
);
1237 vblank
->inmodeset
= 1;
1239 spin_unlock(&dev
->vbl_lock
);
1241 /* Send any queued vblank events, lest the natives grow disquiet */
1242 seq
= drm_vblank_count_and_time(dev
, pipe
, &now
);
1244 list_for_each_entry_safe(e
, t
, &dev
->vblank_event_list
, base
.link
) {
1245 if (e
->pipe
!= pipe
)
1247 DRM_DEBUG("Sending premature vblank event on disable: \
1248 wanted %d, current %d\n",
1249 e
->event
.sequence
, seq
);
1250 list_del(&e
->base
.link
);
1251 drm_vblank_put(dev
, pipe
);
1252 send_vblank_event(dev
, e
, seq
, &now
);
1254 spin_unlock_irqrestore(&dev
->event_lock
, irqflags
);
1256 EXPORT_SYMBOL(drm_vblank_off
);
1259 * drm_crtc_vblank_off - disable vblank events on a CRTC
1260 * @crtc: CRTC in question
1262 * Drivers can use this function to shut down the vblank interrupt handling when
1263 * disabling a crtc. This function ensures that the latest vblank frame count is
1264 * stored so that drm_vblank_on can restore it again.
1266 * Drivers must use this function when the hardware vblank counter can get
1267 * reset, e.g. when suspending.
1269 * This is the native kms version of drm_vblank_off().
1271 void drm_crtc_vblank_off(struct drm_crtc
*crtc
)
1273 drm_vblank_off(crtc
->dev
, drm_crtc_index(crtc
));
1275 EXPORT_SYMBOL(drm_crtc_vblank_off
);
1278 * drm_crtc_vblank_reset - reset vblank state to off on a CRTC
1279 * @drm_crtc: CRTC in question
1281 * Drivers can use this function to reset the vblank state to off at load time.
1282 * Drivers should use this together with the drm_crtc_vblank_off() and
1283 * drm_crtc_vblank_on() functions. The difference compared to
1284 * drm_crtc_vblank_off() is that this function doesn't save the vblank counter
1285 * and hence doesn't need to call any driver hooks.
1287 void drm_crtc_vblank_reset(struct drm_crtc
*drm_crtc
)
1289 struct drm_device
*dev
= drm_crtc
->dev
;
1290 unsigned long irqflags
;
1291 int crtc
= drm_crtc_index(drm_crtc
);
1292 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[crtc
];
1294 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
1296 * Prevent subsequent drm_vblank_get() from enabling the vblank
1297 * interrupt by bumping the refcount.
1299 if (!vblank
->inmodeset
) {
1300 atomic_inc(&vblank
->refcount
);
1301 vblank
->inmodeset
= 1;
1303 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
1305 WARN_ON(!list_empty(&dev
->vblank_event_list
));
1307 EXPORT_SYMBOL(drm_crtc_vblank_reset
);
1310 * drm_vblank_on - enable vblank events on a CRTC
1314 * This functions restores the vblank interrupt state captured with
1315 * drm_vblank_off() again. Note that calls to drm_vblank_on() and
1316 * drm_vblank_off() can be unbalanced and so can also be unconditionally called
1317 * in driver load code to reflect the current hardware state of the crtc.
1319 * This is the legacy version of drm_crtc_vblank_on().
1321 void drm_vblank_on(struct drm_device
*dev
, unsigned int pipe
)
1323 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1324 unsigned long irqflags
;
1326 if (WARN_ON(pipe
>= dev
->num_crtcs
))
1329 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
1330 /* Drop our private "prevent drm_vblank_get" refcount */
1331 if (vblank
->inmodeset
) {
1332 atomic_dec(&vblank
->refcount
);
1333 vblank
->inmodeset
= 0;
1337 * sample the current counter to avoid random jumps
1338 * when drm_vblank_enable() applies the diff
1340 * -1 to make sure user will never see the same
1341 * vblank counter value before and after a modeset
1344 (dev
->driver
->get_vblank_counter(dev
, pipe
) - 1) &
1345 dev
->max_vblank_count
;
1347 * re-enable interrupts if there are users left, or the
1348 * user wishes vblank interrupts to be enabled all the time.
1350 if (atomic_read(&vblank
->refcount
) != 0 ||
1351 (!dev
->vblank_disable_immediate
&& drm_vblank_offdelay
== 0))
1352 WARN_ON(drm_vblank_enable(dev
, pipe
));
1353 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
1355 EXPORT_SYMBOL(drm_vblank_on
);
1358 * drm_crtc_vblank_on - enable vblank events on a CRTC
1359 * @crtc: CRTC in question
1361 * This functions restores the vblank interrupt state captured with
1362 * drm_vblank_off() again. Note that calls to drm_vblank_on() and
1363 * drm_vblank_off() can be unbalanced and so can also be unconditionally called
1364 * in driver load code to reflect the current hardware state of the crtc.
1366 * This is the native kms version of drm_vblank_on().
1368 void drm_crtc_vblank_on(struct drm_crtc
*crtc
)
1370 drm_vblank_on(crtc
->dev
, drm_crtc_index(crtc
));
1372 EXPORT_SYMBOL(drm_crtc_vblank_on
);
1375 * drm_vblank_pre_modeset - account for vblanks across mode sets
1379 * Account for vblank events across mode setting events, which will likely
1380 * reset the hardware frame counter.
1382 * This is done by grabbing a temporary vblank reference to ensure that the
1383 * vblank interrupt keeps running across the modeset sequence. With this the
1384 * software-side vblank frame counting will ensure that there are no jumps or
1387 * Unfortunately this approach is racy and also doesn't work when the vblank
1388 * interrupt stops running, e.g. across system suspend resume. It is therefore
1389 * highly recommended that drivers use the newer drm_vblank_off() and
1390 * drm_vblank_on() instead. drm_vblank_pre_modeset() only works correctly when
1391 * using "cooked" software vblank frame counters and not relying on any hardware
1394 * Drivers must call drm_vblank_post_modeset() when re-enabling the same crtc
1397 void drm_vblank_pre_modeset(struct drm_device
*dev
, unsigned int pipe
)
1399 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1401 /* vblank is not initialized (IRQ not installed ?), or has been freed */
1402 if (!dev
->num_crtcs
)
1405 if (WARN_ON(pipe
>= dev
->num_crtcs
))
1409 * To avoid all the problems that might happen if interrupts
1410 * were enabled/disabled around or between these calls, we just
1411 * have the kernel take a reference on the CRTC (just once though
1412 * to avoid corrupting the count if multiple, mismatch calls occur),
1413 * so that interrupts remain enabled in the interim.
1415 if (!vblank
->inmodeset
) {
1416 vblank
->inmodeset
= 0x1;
1417 if (drm_vblank_get(dev
, pipe
) == 0)
1418 vblank
->inmodeset
|= 0x2;
1421 EXPORT_SYMBOL(drm_vblank_pre_modeset
);
1424 * drm_vblank_post_modeset - undo drm_vblank_pre_modeset changes
1428 * This function again drops the temporary vblank reference acquired in
1429 * drm_vblank_pre_modeset.
1431 void drm_vblank_post_modeset(struct drm_device
*dev
, unsigned int pipe
)
1433 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1434 unsigned long irqflags
;
1436 /* vblank is not initialized (IRQ not installed ?), or has been freed */
1437 if (!dev
->num_crtcs
)
1440 if (WARN_ON(pipe
>= dev
->num_crtcs
))
1443 if (vblank
->inmodeset
) {
1444 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
1445 dev
->vblank_disable_allowed
= true;
1446 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
1448 if (vblank
->inmodeset
& 0x2)
1449 drm_vblank_put(dev
, pipe
);
1451 vblank
->inmodeset
= 0;
1454 EXPORT_SYMBOL(drm_vblank_post_modeset
);
1457 * drm_modeset_ctl - handle vblank event counter changes across mode switch
1458 * @DRM_IOCTL_ARGS: standard ioctl arguments
1460 * Applications should call the %_DRM_PRE_MODESET and %_DRM_POST_MODESET
1461 * ioctls around modesetting so that any lost vblank events are accounted for.
1463 * Generally the counter will reset across mode sets. If interrupts are
1464 * enabled around this call, we don't have to do anything since the counter
1465 * will have already been incremented.
1467 int drm_modeset_ctl(struct drm_device
*dev
, void *data
,
1468 struct drm_file
*file_priv
)
1470 struct drm_modeset_ctl
*modeset
= data
;
1473 /* If drm_vblank_init() hasn't been called yet, just no-op */
1474 if (!dev
->num_crtcs
)
1477 /* KMS drivers handle this internally */
1478 if (drm_core_check_feature(dev
, DRIVER_MODESET
))
1481 pipe
= modeset
->crtc
;
1482 if (pipe
>= dev
->num_crtcs
)
1485 switch (modeset
->cmd
) {
1486 case _DRM_PRE_MODESET
:
1487 drm_vblank_pre_modeset(dev
, pipe
);
1489 case _DRM_POST_MODESET
:
1490 drm_vblank_post_modeset(dev
, pipe
);
1499 static int drm_queue_vblank_event(struct drm_device
*dev
, unsigned int pipe
,
1500 union drm_wait_vblank
*vblwait
,
1501 struct drm_file
*file_priv
)
1503 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1504 struct drm_pending_vblank_event
*e
;
1506 unsigned long flags
;
1510 e
= kzalloc(sizeof(*e
), GFP_KERNEL
);
1517 e
->base
.pid
= current
->pid
;
1518 e
->event
.base
.type
= DRM_EVENT_VBLANK
;
1519 e
->event
.base
.length
= sizeof(e
->event
);
1520 e
->event
.user_data
= vblwait
->request
.signal
;
1521 e
->base
.event
= &e
->event
.base
;
1522 e
->base
.file_priv
= file_priv
;
1523 e
->base
.destroy
= (void (*) (struct drm_pending_event
*)) kfree
;
1525 spin_lock_irqsave(&dev
->event_lock
, flags
);
1528 * drm_vblank_off() might have been called after we called
1529 * drm_vblank_get(). drm_vblank_off() holds event_lock
1530 * around the vblank disable, so no need for further locking.
1531 * The reference from drm_vblank_get() protects against
1532 * vblank disable from another source.
1534 if (!vblank
->enabled
) {
1539 if (file_priv
->event_space
< sizeof(e
->event
)) {
1544 file_priv
->event_space
-= sizeof(e
->event
);
1545 seq
= drm_vblank_count_and_time(dev
, pipe
, &now
);
1547 if ((vblwait
->request
.type
& _DRM_VBLANK_NEXTONMISS
) &&
1548 (seq
- vblwait
->request
.sequence
) <= (1 << 23)) {
1549 vblwait
->request
.sequence
= seq
+ 1;
1550 vblwait
->reply
.sequence
= vblwait
->request
.sequence
;
1553 DRM_DEBUG("event on vblank count %d, current %d, crtc %u\n",
1554 vblwait
->request
.sequence
, seq
, pipe
);
1556 trace_drm_vblank_event_queued(current
->pid
, pipe
,
1557 vblwait
->request
.sequence
);
1559 e
->event
.sequence
= vblwait
->request
.sequence
;
1560 if ((seq
- vblwait
->request
.sequence
) <= (1 << 23)) {
1561 drm_vblank_put(dev
, pipe
);
1562 send_vblank_event(dev
, e
, seq
, &now
);
1563 vblwait
->reply
.sequence
= seq
;
1565 /* drm_handle_vblank_events will call drm_vblank_put */
1566 list_add_tail(&e
->base
.link
, &dev
->vblank_event_list
);
1567 vblwait
->reply
.sequence
= vblwait
->request
.sequence
;
1570 spin_unlock_irqrestore(&dev
->event_lock
, flags
);
1575 spin_unlock_irqrestore(&dev
->event_lock
, flags
);
1578 drm_vblank_put(dev
, pipe
);
1585 * \param inode device inode.
1586 * \param file_priv DRM file private.
1587 * \param cmd command.
1588 * \param data user argument, pointing to a drm_wait_vblank structure.
1589 * \return zero on success or a negative number on failure.
1591 * This function enables the vblank interrupt on the pipe requested, then
1592 * sleeps waiting for the requested sequence number to occur, and drops
1593 * the vblank interrupt refcount afterwards. (vblank IRQ disable follows that
1594 * after a timeout with no further vblank waits scheduled).
1596 int drm_wait_vblank(struct drm_device
*dev
, void *data
,
1597 struct drm_file
*file_priv
)
1599 struct drm_vblank_crtc
*vblank
;
1600 union drm_wait_vblank
*vblwait
= data
;
1602 unsigned int flags
, seq
, pipe
, high_pipe
;
1604 if (!dev
->irq_enabled
)
1607 if (vblwait
->request
.type
& _DRM_VBLANK_SIGNAL
)
1610 if (vblwait
->request
.type
&
1611 ~(_DRM_VBLANK_TYPES_MASK
| _DRM_VBLANK_FLAGS_MASK
|
1612 _DRM_VBLANK_HIGH_CRTC_MASK
)) {
1613 DRM_ERROR("Unsupported type value 0x%x, supported mask 0x%x\n",
1614 vblwait
->request
.type
,
1615 (_DRM_VBLANK_TYPES_MASK
| _DRM_VBLANK_FLAGS_MASK
|
1616 _DRM_VBLANK_HIGH_CRTC_MASK
));
1620 flags
= vblwait
->request
.type
& _DRM_VBLANK_FLAGS_MASK
;
1621 high_pipe
= (vblwait
->request
.type
& _DRM_VBLANK_HIGH_CRTC_MASK
);
1623 pipe
= high_pipe
>> _DRM_VBLANK_HIGH_CRTC_SHIFT
;
1625 pipe
= flags
& _DRM_VBLANK_SECONDARY
? 1 : 0;
1626 if (pipe
>= dev
->num_crtcs
)
1629 vblank
= &dev
->vblank
[pipe
];
1631 ret
= drm_vblank_get(dev
, pipe
);
1633 DRM_DEBUG("failed to acquire vblank counter, %d\n", ret
);
1636 seq
= drm_vblank_count(dev
, pipe
);
1638 switch (vblwait
->request
.type
& _DRM_VBLANK_TYPES_MASK
) {
1639 case _DRM_VBLANK_RELATIVE
:
1640 vblwait
->request
.sequence
+= seq
;
1641 vblwait
->request
.type
&= ~_DRM_VBLANK_RELATIVE
;
1642 case _DRM_VBLANK_ABSOLUTE
:
1649 if (flags
& _DRM_VBLANK_EVENT
) {
1650 /* must hold on to the vblank ref until the event fires
1651 * drm_vblank_put will be called asynchronously
1653 return drm_queue_vblank_event(dev
, pipe
, vblwait
, file_priv
);
1656 if ((flags
& _DRM_VBLANK_NEXTONMISS
) &&
1657 (seq
- vblwait
->request
.sequence
) <= (1<<23)) {
1658 vblwait
->request
.sequence
= seq
+ 1;
1661 DRM_DEBUG("waiting on vblank count %d, crtc %u\n",
1662 vblwait
->request
.sequence
, pipe
);
1663 vblank
->last_wait
= vblwait
->request
.sequence
;
1664 DRM_WAIT_ON(ret
, vblank
->queue
, 3 * HZ
,
1665 (((drm_vblank_count(dev
, pipe
) -
1666 vblwait
->request
.sequence
) <= (1 << 23)) ||
1668 !dev
->irq_enabled
));
1670 if (ret
!= -EINTR
) {
1673 vblwait
->reply
.sequence
= drm_vblank_count_and_time(dev
, pipe
, &now
);
1674 vblwait
->reply
.tval_sec
= now
.tv_sec
;
1675 vblwait
->reply
.tval_usec
= now
.tv_usec
;
1677 DRM_DEBUG("returning %d to client\n",
1678 vblwait
->reply
.sequence
);
1680 DRM_DEBUG("vblank wait interrupted by signal\n");
1684 drm_vblank_put(dev
, pipe
);
1688 static void drm_handle_vblank_events(struct drm_device
*dev
, unsigned int pipe
)
1690 struct drm_pending_vblank_event
*e
, *t
;
1694 assert_spin_locked(&dev
->event_lock
);
1696 seq
= drm_vblank_count_and_time(dev
, pipe
, &now
);
1698 list_for_each_entry_safe(e
, t
, &dev
->vblank_event_list
, base
.link
) {
1699 if (e
->pipe
!= pipe
)
1701 if ((seq
- e
->event
.sequence
) > (1<<23))
1704 DRM_DEBUG("vblank event on %d, current %d\n",
1705 e
->event
.sequence
, seq
);
1707 list_del(&e
->base
.link
);
1708 drm_vblank_put(dev
, pipe
);
1709 send_vblank_event(dev
, e
, seq
, &now
);
1712 trace_drm_vblank_event(pipe
, seq
);
1716 * drm_handle_vblank - handle a vblank event
1718 * @pipe: index of CRTC where this event occurred
1720 * Drivers should call this routine in their vblank interrupt handlers to
1721 * update the vblank counter and send any signals that may be pending.
1723 * This is the legacy version of drm_crtc_handle_vblank().
1725 bool drm_handle_vblank(struct drm_device
*dev
, unsigned int pipe
)
1727 struct drm_vblank_crtc
*vblank
= &dev
->vblank
[pipe
];
1730 struct timeval tvblank
;
1731 unsigned long irqflags
;
1733 if (WARN_ON_ONCE(!dev
->num_crtcs
))
1736 if (WARN_ON(pipe
>= dev
->num_crtcs
))
1739 spin_lock_irqsave(&dev
->event_lock
, irqflags
);
1741 /* Need timestamp lock to prevent concurrent execution with
1742 * vblank enable/disable, as this would cause inconsistent
1743 * or corrupted timestamps and vblank counts.
1745 spin_lock(&dev
->vblank_time_lock
);
1747 /* Vblank irq handling disabled. Nothing to do. */
1748 if (!vblank
->enabled
) {
1749 spin_unlock(&dev
->vblank_time_lock
);
1750 spin_unlock_irqrestore(&dev
->event_lock
, irqflags
);
1754 /* Fetch corresponding timestamp for this vblank interval from
1755 * driver and store it in proper slot of timestamp ringbuffer.
1758 /* Get current timestamp and count. */
1759 vblcount
= vblank
->count
;
1760 drm_get_last_vbltimestamp(dev
, pipe
, &tvblank
, DRM_CALLED_FROM_VBLIRQ
);
1762 /* Compute time difference to timestamp of last vblank */
1763 diff_ns
= timeval_to_ns(&tvblank
) -
1764 timeval_to_ns(&vblanktimestamp(dev
, pipe
, vblcount
));
1766 /* Update vblank timestamp and count if at least
1767 * DRM_REDUNDANT_VBLIRQ_THRESH_NS nanoseconds
1768 * difference between last stored timestamp and current
1769 * timestamp. A smaller difference means basically
1770 * identical timestamps. Happens if this vblank has
1771 * been already processed and this is a redundant call,
1772 * e.g., due to spurious vblank interrupts. We need to
1773 * ignore those for accounting.
1775 if (abs64(diff_ns
) > DRM_REDUNDANT_VBLIRQ_THRESH_NS
)
1776 store_vblank(dev
, pipe
, 1, &tvblank
);
1778 DRM_DEBUG("crtc %u: Redundant vblirq ignored. diff_ns = %d\n",
1779 pipe
, (int) diff_ns
);
1781 spin_unlock(&dev
->vblank_time_lock
);
1783 wake_up(&vblank
->queue
);
1784 drm_handle_vblank_events(dev
, pipe
);
1786 spin_unlock_irqrestore(&dev
->event_lock
, irqflags
);
1790 EXPORT_SYMBOL(drm_handle_vblank
);
1793 * drm_crtc_handle_vblank - handle a vblank event
1794 * @crtc: where this event occurred
1796 * Drivers should call this routine in their vblank interrupt handlers to
1797 * update the vblank counter and send any signals that may be pending.
1799 * This is the native KMS version of drm_handle_vblank().
1802 * True if the event was successfully handled, false on failure.
1804 bool drm_crtc_handle_vblank(struct drm_crtc
*crtc
)
1806 return drm_handle_vblank(crtc
->dev
, drm_crtc_index(crtc
));
1808 EXPORT_SYMBOL(drm_crtc_handle_vblank
);