5 * \author Rickard E. (Rik) Faith <faith@valinux.com>
6 * \author Gareth Hughes <gareth@valinux.com>
10 * Created: Fri Mar 19 14:30:16 1999 by faith@valinux.com
12 * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
13 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
14 * All Rights Reserved.
16 * Permission is hereby granted, free of charge, to any person obtaining a
17 * copy of this software and associated documentation files (the "Software"),
18 * to deal in the Software without restriction, including without limitation
19 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
20 * and/or sell copies of the Software, and to permit persons to whom the
21 * Software is furnished to do so, subject to the following conditions:
23 * The above copyright notice and this permission notice (including the next
24 * paragraph) shall be included in all copies or substantial portions of the
27 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
28 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
29 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
30 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
31 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
32 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
33 * OTHER DEALINGS IN THE SOFTWARE.
37 #include "drm_trace.h"
39 #include <linux/interrupt.h> /* For task queue support */
40 #include <linux/slab.h>
42 #include <linux/vgaarb.h>
44 /* Access macro for slots in vblank timestamp ringbuffer. */
45 #define vblanktimestamp(dev, crtc, count) ( \
46 (dev)->_vblank_time[(crtc) * DRM_VBLANKTIME_RBSIZE + \
47 ((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 * Get interrupt from bus id.
62 * \param inode device inode.
63 * \param file_priv DRM file private.
65 * \param arg user argument, pointing to a drm_irq_busid structure.
66 * \return zero on success or a negative number on failure.
68 * Finds the PCI device with the specified bus id and gets its IRQ number.
69 * This IOCTL is deprecated, and will now return EINVAL for any busid not equal
70 * to that of the device that this DRM instance attached to.
72 int drm_irq_by_busid(struct drm_device
*dev
, void *data
,
73 struct drm_file
*file_priv
)
75 struct drm_irq_busid
*p
= data
;
77 if (!dev
->driver
->bus
->irq_by_busid
)
80 if (!drm_core_check_feature(dev
, DRIVER_HAVE_IRQ
))
83 return dev
->driver
->bus
->irq_by_busid(dev
, p
);
87 * Clear vblank timestamp buffer for a crtc.
89 static void clear_vblank_timestamps(struct drm_device
*dev
, int crtc
)
91 memset(&dev
->_vblank_time
[crtc
* DRM_VBLANKTIME_RBSIZE
], 0,
92 DRM_VBLANKTIME_RBSIZE
* sizeof(struct timeval
));
96 * Disable vblank irq's on crtc, make sure that last vblank count
97 * of hardware and corresponding consistent software vblank counter
98 * are preserved, even if there are any spurious vblank irq's after
101 static void vblank_disable_and_save(struct drm_device
*dev
, int crtc
)
103 unsigned long irqflags
;
107 struct timeval tvblank
;
109 /* Prevent vblank irq processing while disabling vblank irqs,
110 * so no updates of timestamps or count can happen after we've
111 * disabled. Needed to prevent races in case of delayed irq's.
112 * Disable preemption, so vblank_time_lock is held as short as
113 * possible, even under a kernel with PREEMPT_RT patches.
116 spin_lock_irqsave(&dev
->vblank_time_lock
, irqflags
);
118 dev
->driver
->disable_vblank(dev
, crtc
);
119 dev
->vblank_enabled
[crtc
] = 0;
121 /* No further vblank irq's will be processed after
122 * this point. Get current hardware vblank count and
123 * vblank timestamp, repeat until they are consistent.
125 * FIXME: There is still a race condition here and in
126 * drm_update_vblank_count() which can cause off-by-one
127 * reinitialization of software vblank counter. If gpu
128 * vblank counter doesn't increment exactly at the leading
129 * edge of a vblank interval, then we can lose 1 count if
130 * we happen to execute between start of vblank and the
131 * delayed gpu counter increment.
134 dev
->last_vblank
[crtc
] = dev
->driver
->get_vblank_counter(dev
, crtc
);
135 vblrc
= drm_get_last_vbltimestamp(dev
, crtc
, &tvblank
, 0);
136 } while (dev
->last_vblank
[crtc
] != dev
->driver
->get_vblank_counter(dev
, crtc
));
138 /* Compute time difference to stored timestamp of last vblank
139 * as updated by last invocation of drm_handle_vblank() in vblank irq.
141 vblcount
= atomic_read(&dev
->_vblank_count
[crtc
]);
142 diff_ns
= timeval_to_ns(&tvblank
) -
143 timeval_to_ns(&vblanktimestamp(dev
, crtc
, vblcount
));
145 /* If there is at least 1 msec difference between the last stored
146 * timestamp and tvblank, then we are currently executing our
147 * disable inside a new vblank interval, the tvblank timestamp
148 * corresponds to this new vblank interval and the irq handler
149 * for this vblank didn't run yet and won't run due to our disable.
150 * Therefore we need to do the job of drm_handle_vblank() and
151 * increment the vblank counter by one to account for this vblank.
153 * Skip this step if there isn't any high precision timestamp
154 * available. In that case we can't account for this and just
157 if ((vblrc
> 0) && (abs64(diff_ns
) > 1000000)) {
158 atomic_inc(&dev
->_vblank_count
[crtc
]);
159 smp_mb__after_atomic_inc();
162 /* Invalidate all timestamps while vblank irq's are off. */
163 clear_vblank_timestamps(dev
, crtc
);
165 spin_unlock_irqrestore(&dev
->vblank_time_lock
, irqflags
);
169 static void vblank_disable_fn(unsigned long arg
)
171 struct drm_device
*dev
= (struct drm_device
*)arg
;
172 unsigned long irqflags
;
175 if (!dev
->vblank_disable_allowed
)
178 for (i
= 0; i
< dev
->num_crtcs
; i
++) {
179 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
180 if (atomic_read(&dev
->vblank_refcount
[i
]) == 0 &&
181 dev
->vblank_enabled
[i
]) {
182 DRM_DEBUG("disabling vblank on crtc %d\n", i
);
183 vblank_disable_and_save(dev
, i
);
185 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
189 void drm_vblank_cleanup(struct drm_device
*dev
)
191 /* Bail if the driver didn't call drm_vblank_init() */
192 if (dev
->num_crtcs
== 0)
195 del_timer(&dev
->vblank_disable_timer
);
197 vblank_disable_fn((unsigned long)dev
);
199 kfree(dev
->vbl_queue
);
200 kfree(dev
->_vblank_count
);
201 kfree(dev
->vblank_refcount
);
202 kfree(dev
->vblank_enabled
);
203 kfree(dev
->last_vblank
);
204 kfree(dev
->last_vblank_wait
);
205 kfree(dev
->vblank_inmodeset
);
206 kfree(dev
->_vblank_time
);
210 EXPORT_SYMBOL(drm_vblank_cleanup
);
212 int drm_vblank_init(struct drm_device
*dev
, int num_crtcs
)
214 int i
, ret
= -ENOMEM
;
216 setup_timer(&dev
->vblank_disable_timer
, vblank_disable_fn
,
218 spin_lock_init(&dev
->vbl_lock
);
219 spin_lock_init(&dev
->vblank_time_lock
);
221 dev
->num_crtcs
= num_crtcs
;
223 dev
->vbl_queue
= kmalloc(sizeof(wait_queue_head_t
) * num_crtcs
,
228 dev
->_vblank_count
= kmalloc(sizeof(atomic_t
) * num_crtcs
, GFP_KERNEL
);
229 if (!dev
->_vblank_count
)
232 dev
->vblank_refcount
= kmalloc(sizeof(atomic_t
) * num_crtcs
,
234 if (!dev
->vblank_refcount
)
237 dev
->vblank_enabled
= kcalloc(num_crtcs
, sizeof(int), GFP_KERNEL
);
238 if (!dev
->vblank_enabled
)
241 dev
->last_vblank
= kcalloc(num_crtcs
, sizeof(u32
), GFP_KERNEL
);
242 if (!dev
->last_vblank
)
245 dev
->last_vblank_wait
= kcalloc(num_crtcs
, sizeof(u32
), GFP_KERNEL
);
246 if (!dev
->last_vblank_wait
)
249 dev
->vblank_inmodeset
= kcalloc(num_crtcs
, sizeof(int), GFP_KERNEL
);
250 if (!dev
->vblank_inmodeset
)
253 dev
->_vblank_time
= kcalloc(num_crtcs
* DRM_VBLANKTIME_RBSIZE
,
254 sizeof(struct timeval
), GFP_KERNEL
);
255 if (!dev
->_vblank_time
)
258 DRM_INFO("Supports vblank timestamp caching Rev 1 (10.10.2010).\n");
260 /* Driver specific high-precision vblank timestamping supported? */
261 if (dev
->driver
->get_vblank_timestamp
)
262 DRM_INFO("Driver supports precise vblank timestamp query.\n");
264 DRM_INFO("No driver support for vblank timestamp query.\n");
266 /* Zero per-crtc vblank stuff */
267 for (i
= 0; i
< num_crtcs
; i
++) {
268 init_waitqueue_head(&dev
->vbl_queue
[i
]);
269 atomic_set(&dev
->_vblank_count
[i
], 0);
270 atomic_set(&dev
->vblank_refcount
[i
], 0);
273 dev
->vblank_disable_allowed
= 0;
277 drm_vblank_cleanup(dev
);
280 EXPORT_SYMBOL(drm_vblank_init
);
282 static void drm_irq_vgaarb_nokms(void *cookie
, bool state
)
284 struct drm_device
*dev
= cookie
;
286 if (dev
->driver
->vgaarb_irq
) {
287 dev
->driver
->vgaarb_irq(dev
, state
);
291 if (!dev
->irq_enabled
)
295 dev
->driver
->irq_uninstall(dev
);
297 dev
->driver
->irq_preinstall(dev
);
298 dev
->driver
->irq_postinstall(dev
);
303 * Install IRQ handler.
305 * \param dev DRM device.
307 * Initializes the IRQ related data. Installs the handler, calling the driver
308 * \c drm_driver_irq_preinstall() and \c drm_driver_irq_postinstall() functions
309 * before and after the installation.
311 int drm_irq_install(struct drm_device
*dev
)
314 unsigned long sh_flags
= 0;
317 if (!drm_core_check_feature(dev
, DRIVER_HAVE_IRQ
))
320 if (drm_dev_to_irq(dev
) == 0)
323 mutex_lock(&dev
->struct_mutex
);
325 /* Driver must have been initialized */
326 if (!dev
->dev_private
) {
327 mutex_unlock(&dev
->struct_mutex
);
331 if (dev
->irq_enabled
) {
332 mutex_unlock(&dev
->struct_mutex
);
335 dev
->irq_enabled
= 1;
336 mutex_unlock(&dev
->struct_mutex
);
338 DRM_DEBUG("irq=%d\n", drm_dev_to_irq(dev
));
340 /* Before installing handler */
341 dev
->driver
->irq_preinstall(dev
);
343 /* Install handler */
344 if (drm_core_check_feature(dev
, DRIVER_IRQ_SHARED
))
345 sh_flags
= IRQF_SHARED
;
348 irqname
= dev
->devname
;
350 irqname
= dev
->driver
->name
;
352 ret
= request_irq(drm_dev_to_irq(dev
), dev
->driver
->irq_handler
,
353 sh_flags
, irqname
, dev
);
356 mutex_lock(&dev
->struct_mutex
);
357 dev
->irq_enabled
= 0;
358 mutex_unlock(&dev
->struct_mutex
);
362 if (!drm_core_check_feature(dev
, DRIVER_MODESET
))
363 vga_client_register(dev
->pdev
, (void *)dev
, drm_irq_vgaarb_nokms
, NULL
);
365 /* After installing handler */
366 ret
= dev
->driver
->irq_postinstall(dev
);
368 mutex_lock(&dev
->struct_mutex
);
369 dev
->irq_enabled
= 0;
370 mutex_unlock(&dev
->struct_mutex
);
371 if (!drm_core_check_feature(dev
, DRIVER_MODESET
))
372 vga_client_register(dev
->pdev
, NULL
, NULL
, NULL
);
373 free_irq(drm_dev_to_irq(dev
), dev
);
378 EXPORT_SYMBOL(drm_irq_install
);
381 * Uninstall the IRQ handler.
383 * \param dev DRM device.
385 * Calls the driver's \c drm_driver_irq_uninstall() function, and stops the irq.
387 int drm_irq_uninstall(struct drm_device
*dev
)
389 unsigned long irqflags
;
392 if (!drm_core_check_feature(dev
, DRIVER_HAVE_IRQ
))
395 mutex_lock(&dev
->struct_mutex
);
396 irq_enabled
= dev
->irq_enabled
;
397 dev
->irq_enabled
= 0;
398 mutex_unlock(&dev
->struct_mutex
);
401 * Wake up any waiters so they don't hang.
403 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
404 for (i
= 0; i
< dev
->num_crtcs
; i
++) {
405 DRM_WAKEUP(&dev
->vbl_queue
[i
]);
406 dev
->vblank_enabled
[i
] = 0;
407 dev
->last_vblank
[i
] = dev
->driver
->get_vblank_counter(dev
, i
);
409 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
414 DRM_DEBUG("irq=%d\n", drm_dev_to_irq(dev
));
416 if (!drm_core_check_feature(dev
, DRIVER_MODESET
))
417 vga_client_register(dev
->pdev
, NULL
, NULL
, NULL
);
419 dev
->driver
->irq_uninstall(dev
);
421 free_irq(drm_dev_to_irq(dev
), dev
);
425 EXPORT_SYMBOL(drm_irq_uninstall
);
430 * \param inode device inode.
431 * \param file_priv DRM file private.
432 * \param cmd command.
433 * \param arg user argument, pointing to a drm_control structure.
434 * \return zero on success or a negative number on failure.
436 * Calls irq_install() or irq_uninstall() according to \p arg.
438 int drm_control(struct drm_device
*dev
, void *data
,
439 struct drm_file
*file_priv
)
441 struct drm_control
*ctl
= data
;
443 /* if we haven't irq we fallback for compatibility reasons -
444 * this used to be a separate function in drm_dma.h
449 case DRM_INST_HANDLER
:
450 if (!drm_core_check_feature(dev
, DRIVER_HAVE_IRQ
))
452 if (drm_core_check_feature(dev
, DRIVER_MODESET
))
454 if (dev
->if_version
< DRM_IF_VERSION(1, 2) &&
455 ctl
->irq
!= drm_dev_to_irq(dev
))
457 return drm_irq_install(dev
);
458 case DRM_UNINST_HANDLER
:
459 if (!drm_core_check_feature(dev
, DRIVER_HAVE_IRQ
))
461 if (drm_core_check_feature(dev
, DRIVER_MODESET
))
463 return drm_irq_uninstall(dev
);
470 * drm_calc_timestamping_constants - Calculate and
471 * store various constants which are later needed by
472 * vblank and swap-completion timestamping, e.g, by
473 * drm_calc_vbltimestamp_from_scanoutpos().
474 * They are derived from crtc's true scanout timing,
475 * so they take things like panel scaling or other
476 * adjustments into account.
478 * @crtc drm_crtc whose timestamp constants should be updated.
481 void drm_calc_timestamping_constants(struct drm_crtc
*crtc
)
483 s64 linedur_ns
= 0, pixeldur_ns
= 0, framedur_ns
= 0;
486 /* Dot clock in Hz: */
487 dotclock
= (u64
) crtc
->hwmode
.clock
* 1000;
489 /* Fields of interlaced scanout modes are only halve a frame duration.
490 * Double the dotclock to get halve the frame-/line-/pixelduration.
492 if (crtc
->hwmode
.flags
& DRM_MODE_FLAG_INTERLACE
)
495 /* Valid dotclock? */
497 /* Convert scanline length in pixels and video dot clock to
498 * line duration, frame duration and pixel duration in
501 pixeldur_ns
= (s64
) div64_u64(1000000000, dotclock
);
502 linedur_ns
= (s64
) div64_u64(((u64
) crtc
->hwmode
.crtc_htotal
*
503 1000000000), dotclock
);
504 framedur_ns
= (s64
) crtc
->hwmode
.crtc_vtotal
* linedur_ns
;
506 DRM_ERROR("crtc %d: Can't calculate constants, dotclock = 0!\n",
509 crtc
->pixeldur_ns
= pixeldur_ns
;
510 crtc
->linedur_ns
= linedur_ns
;
511 crtc
->framedur_ns
= framedur_ns
;
513 DRM_DEBUG("crtc %d: hwmode: htotal %d, vtotal %d, vdisplay %d\n",
514 crtc
->base
.id
, crtc
->hwmode
.crtc_htotal
,
515 crtc
->hwmode
.crtc_vtotal
, crtc
->hwmode
.crtc_vdisplay
);
516 DRM_DEBUG("crtc %d: clock %d kHz framedur %d linedur %d, pixeldur %d\n",
517 crtc
->base
.id
, (int) dotclock
/1000, (int) framedur_ns
,
518 (int) linedur_ns
, (int) pixeldur_ns
);
520 EXPORT_SYMBOL(drm_calc_timestamping_constants
);
523 * drm_calc_vbltimestamp_from_scanoutpos - helper routine for kms
524 * drivers. Implements calculation of exact vblank timestamps from
525 * given drm_display_mode timings and current video scanout position
526 * of a crtc. This can be called from within get_vblank_timestamp()
527 * implementation of a kms driver to implement the actual timestamping.
529 * Should return timestamps conforming to the OML_sync_control OpenML
530 * extension specification. The timestamp corresponds to the end of
531 * the vblank interval, aka start of scanout of topmost-leftmost display
532 * pixel in the following video frame.
534 * Requires support for optional dev->driver->get_scanout_position()
535 * in kms driver, plus a bit of setup code to provide a drm_display_mode
536 * that corresponds to the true scanout timing.
538 * The current implementation only handles standard video modes. It
539 * returns as no operation if a doublescan or interlaced video mode is
540 * active. Higher level code is expected to handle this.
543 * @crtc: Which crtc's vblank timestamp to retrieve.
544 * @max_error: Desired maximum allowable error in timestamps (nanosecs).
545 * On return contains true maximum error of timestamp.
546 * @vblank_time: Pointer to struct timeval which should receive the timestamp.
547 * @flags: Flags to pass to driver:
549 * DRM_CALLED_FROM_VBLIRQ = If function is called from vbl irq handler.
550 * @refcrtc: drm_crtc* of crtc which defines scanout timing.
552 * Returns negative value on error, failure or if not supported in current
555 * -EINVAL - Invalid crtc.
556 * -EAGAIN - Temporary unavailable, e.g., called before initial modeset.
557 * -ENOTSUPP - Function not supported in current display mode.
558 * -EIO - Failed, e.g., due to failed scanout position query.
560 * Returns or'ed positive status flags on success:
562 * DRM_VBLANKTIME_SCANOUTPOS_METHOD - Signal this method used for timestamping.
563 * DRM_VBLANKTIME_INVBL - Timestamp taken while scanout was in vblank interval.
566 int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device
*dev
, int crtc
,
568 struct timeval
*vblank_time
,
570 struct drm_crtc
*refcrtc
)
572 struct timeval stime
, raw_time
;
573 struct drm_display_mode
*mode
;
574 int vbl_status
, vtotal
, vdisplay
;
576 s64 framedur_ns
, linedur_ns
, pixeldur_ns
, delta_ns
, duration_ns
;
579 if (crtc
< 0 || crtc
>= dev
->num_crtcs
) {
580 DRM_ERROR("Invalid crtc %d\n", crtc
);
584 /* Scanout position query not supported? Should not happen. */
585 if (!dev
->driver
->get_scanout_position
) {
586 DRM_ERROR("Called from driver w/o get_scanout_position()!?\n");
590 mode
= &refcrtc
->hwmode
;
591 vtotal
= mode
->crtc_vtotal
;
592 vdisplay
= mode
->crtc_vdisplay
;
594 /* Durations of frames, lines, pixels in nanoseconds. */
595 framedur_ns
= refcrtc
->framedur_ns
;
596 linedur_ns
= refcrtc
->linedur_ns
;
597 pixeldur_ns
= refcrtc
->pixeldur_ns
;
599 /* If mode timing undefined, just return as no-op:
600 * Happens during initial modesetting of a crtc.
602 if (vtotal
<= 0 || vdisplay
<= 0 || framedur_ns
== 0) {
603 DRM_DEBUG("crtc %d: Noop due to uninitialized mode.\n", crtc
);
607 /* Get current scanout position with system timestamp.
608 * Repeat query up to DRM_TIMESTAMP_MAXRETRIES times
609 * if single query takes longer than max_error nanoseconds.
611 * This guarantees a tight bound on maximum error if
612 * code gets preempted or delayed for some reason.
614 for (i
= 0; i
< DRM_TIMESTAMP_MAXRETRIES
; i
++) {
615 /* Disable preemption to make it very likely to
616 * succeed in the first iteration even on PREEMPT_RT kernel.
620 /* Get system timestamp before query. */
621 do_gettimeofday(&stime
);
623 /* Get vertical and horizontal scanout pos. vpos, hpos. */
624 vbl_status
= dev
->driver
->get_scanout_position(dev
, crtc
, &vpos
, &hpos
);
626 /* Get system timestamp after query. */
627 do_gettimeofday(&raw_time
);
631 /* Return as no-op if scanout query unsupported or failed. */
632 if (!(vbl_status
& DRM_SCANOUTPOS_VALID
)) {
633 DRM_DEBUG("crtc %d : scanoutpos query failed [%d].\n",
638 duration_ns
= timeval_to_ns(&raw_time
) - timeval_to_ns(&stime
);
640 /* Accept result with < max_error nsecs timing uncertainty. */
641 if (duration_ns
<= (s64
) *max_error
)
645 /* Noisy system timing? */
646 if (i
== DRM_TIMESTAMP_MAXRETRIES
) {
647 DRM_DEBUG("crtc %d: Noisy timestamp %d us > %d us [%d reps].\n",
648 crtc
, (int) duration_ns
/1000, *max_error
/1000, i
);
651 /* Return upper bound of timestamp precision error. */
652 *max_error
= (int) duration_ns
;
654 /* Check if in vblank area:
655 * vpos is >=0 in video scanout area, but negative
656 * within vblank area, counting down the number of lines until
659 invbl
= vbl_status
& DRM_SCANOUTPOS_INVBL
;
661 /* Convert scanout position into elapsed time at raw_time query
662 * since start of scanout at first display scanline. delta_ns
663 * can be negative if start of scanout hasn't happened yet.
665 delta_ns
= (s64
) vpos
* linedur_ns
+ (s64
) hpos
* pixeldur_ns
;
667 /* Is vpos outside nominal vblank area, but less than
668 * 1/100 of a frame height away from start of vblank?
669 * If so, assume this isn't a massively delayed vblank
670 * interrupt, but a vblank interrupt that fired a few
671 * microseconds before true start of vblank. Compensate
672 * by adding a full frame duration to the final timestamp.
673 * Happens, e.g., on ATI R500, R600.
675 * We only do this if DRM_CALLED_FROM_VBLIRQ.
677 if ((flags
& DRM_CALLED_FROM_VBLIRQ
) && !invbl
&&
678 ((vdisplay
- vpos
) < vtotal
/ 100)) {
679 delta_ns
= delta_ns
- framedur_ns
;
681 /* Signal this correction as "applied". */
685 /* Subtract time delta from raw timestamp to get final
686 * vblank_time timestamp for end of vblank.
688 *vblank_time
= ns_to_timeval(timeval_to_ns(&raw_time
) - delta_ns
);
690 DRM_DEBUG("crtc %d : v %d p(%d,%d)@ %ld.%ld -> %ld.%ld [e %d us, %d rep]\n",
691 crtc
, (int)vbl_status
, hpos
, vpos
,
692 (long)raw_time
.tv_sec
, (long)raw_time
.tv_usec
,
693 (long)vblank_time
->tv_sec
, (long)vblank_time
->tv_usec
,
694 (int)duration_ns
/1000, i
);
696 vbl_status
= DRM_VBLANKTIME_SCANOUTPOS_METHOD
;
698 vbl_status
|= DRM_VBLANKTIME_INVBL
;
702 EXPORT_SYMBOL(drm_calc_vbltimestamp_from_scanoutpos
);
705 * drm_get_last_vbltimestamp - retrieve raw timestamp for the most recent
709 * @crtc: which crtc's vblank timestamp to retrieve
710 * @tvblank: Pointer to target struct timeval which should receive the timestamp
711 * @flags: Flags to pass to driver:
713 * DRM_CALLED_FROM_VBLIRQ = If function is called from vbl irq handler.
715 * Fetches the system timestamp corresponding to the time of the most recent
716 * vblank interval on specified crtc. May call into kms-driver to
717 * compute the timestamp with a high-precision GPU specific method.
719 * Returns zero if timestamp originates from uncorrected do_gettimeofday()
720 * call, i.e., it isn't very precisely locked to the true vblank.
722 * Returns non-zero if timestamp is considered to be very precise.
724 u32
drm_get_last_vbltimestamp(struct drm_device
*dev
, int crtc
,
725 struct timeval
*tvblank
, unsigned flags
)
729 /* Define requested maximum error on timestamps (nanoseconds). */
730 int max_error
= (int) drm_timestamp_precision
* 1000;
732 /* Query driver if possible and precision timestamping enabled. */
733 if (dev
->driver
->get_vblank_timestamp
&& (max_error
> 0)) {
734 ret
= dev
->driver
->get_vblank_timestamp(dev
, crtc
, &max_error
,
740 /* GPU high precision timestamp query unsupported or failed.
741 * Return gettimeofday timestamp as best estimate.
743 do_gettimeofday(tvblank
);
747 EXPORT_SYMBOL(drm_get_last_vbltimestamp
);
750 * drm_vblank_count - retrieve "cooked" vblank counter value
752 * @crtc: which counter to retrieve
754 * Fetches the "cooked" vblank count value that represents the number of
755 * vblank events since the system was booted, including lost events due to
756 * modesetting activity.
758 u32
drm_vblank_count(struct drm_device
*dev
, int crtc
)
760 return atomic_read(&dev
->_vblank_count
[crtc
]);
762 EXPORT_SYMBOL(drm_vblank_count
);
765 * drm_vblank_count_and_time - retrieve "cooked" vblank counter value
766 * and the system timestamp corresponding to that vblank counter value.
769 * @crtc: which counter to retrieve
770 * @vblanktime: Pointer to struct timeval to receive the vblank timestamp.
772 * Fetches the "cooked" vblank count value that represents the number of
773 * vblank events since the system was booted, including lost events due to
774 * modesetting activity. Returns corresponding system timestamp of the time
775 * of the vblank interval that corresponds to the current value vblank counter
778 u32
drm_vblank_count_and_time(struct drm_device
*dev
, int crtc
,
779 struct timeval
*vblanktime
)
783 /* Read timestamp from slot of _vblank_time ringbuffer
784 * that corresponds to current vblank count. Retry if
785 * count has incremented during readout. This works like
789 cur_vblank
= atomic_read(&dev
->_vblank_count
[crtc
]);
790 *vblanktime
= vblanktimestamp(dev
, crtc
, cur_vblank
);
792 } while (cur_vblank
!= atomic_read(&dev
->_vblank_count
[crtc
]));
796 EXPORT_SYMBOL(drm_vblank_count_and_time
);
799 * drm_update_vblank_count - update the master vblank counter
801 * @crtc: counter to update
803 * Call back into the driver to update the appropriate vblank counter
804 * (specified by @crtc). Deal with wraparound, if it occurred, and
805 * update the last read value so we can deal with wraparound on the next
808 * Only necessary when going from off->on, to account for frames we
809 * didn't get an interrupt for.
811 * Note: caller must hold dev->vbl_lock since this reads & writes
812 * device vblank fields.
814 static void drm_update_vblank_count(struct drm_device
*dev
, int crtc
)
816 u32 cur_vblank
, diff
, tslot
, rc
;
817 struct timeval t_vblank
;
820 * Interrupts were disabled prior to this call, so deal with counter
822 * NOTE! It's possible we lost a full dev->max_vblank_count events
823 * here if the register is small or we had vblank interrupts off for
826 * We repeat the hardware vblank counter & timestamp query until
827 * we get consistent results. This to prevent races between gpu
828 * updating its hardware counter while we are retrieving the
829 * corresponding vblank timestamp.
832 cur_vblank
= dev
->driver
->get_vblank_counter(dev
, crtc
);
833 rc
= drm_get_last_vbltimestamp(dev
, crtc
, &t_vblank
, 0);
834 } while (cur_vblank
!= dev
->driver
->get_vblank_counter(dev
, crtc
));
836 /* Deal with counter wrap */
837 diff
= cur_vblank
- dev
->last_vblank
[crtc
];
838 if (cur_vblank
< dev
->last_vblank
[crtc
]) {
839 diff
+= dev
->max_vblank_count
;
841 DRM_DEBUG("last_vblank[%d]=0x%x, cur_vblank=0x%x => diff=0x%x\n",
842 crtc
, dev
->last_vblank
[crtc
], cur_vblank
, diff
);
845 DRM_DEBUG("enabling vblank interrupts on crtc %d, missed %d\n",
848 /* Reinitialize corresponding vblank timestamp if high-precision query
849 * available. Skip this step if query unsupported or failed. Will
850 * reinitialize delayed at next vblank interrupt in that case.
853 tslot
= atomic_read(&dev
->_vblank_count
[crtc
]) + diff
;
854 vblanktimestamp(dev
, crtc
, tslot
) = t_vblank
;
857 smp_mb__before_atomic_inc();
858 atomic_add(diff
, &dev
->_vblank_count
[crtc
]);
859 smp_mb__after_atomic_inc();
863 * drm_vblank_get - get a reference count on vblank events
865 * @crtc: which CRTC to own
867 * Acquire a reference count on vblank events to avoid having them disabled
871 * Zero on success, nonzero on failure.
873 int drm_vblank_get(struct drm_device
*dev
, int crtc
)
875 unsigned long irqflags
, irqflags2
;
878 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
879 /* Going from 0->1 means we have to enable interrupts again */
880 if (atomic_add_return(1, &dev
->vblank_refcount
[crtc
]) == 1) {
881 /* Disable preemption while holding vblank_time_lock. Do
882 * it explicitely to guard against PREEMPT_RT kernel.
885 spin_lock_irqsave(&dev
->vblank_time_lock
, irqflags2
);
886 if (!dev
->vblank_enabled
[crtc
]) {
887 /* Enable vblank irqs under vblank_time_lock protection.
888 * All vblank count & timestamp updates are held off
889 * until we are done reinitializing master counter and
890 * timestamps. Filtercode in drm_handle_vblank() will
891 * prevent double-accounting of same vblank interval.
893 ret
= dev
->driver
->enable_vblank(dev
, crtc
);
894 DRM_DEBUG("enabling vblank on crtc %d, ret: %d\n",
897 atomic_dec(&dev
->vblank_refcount
[crtc
]);
899 dev
->vblank_enabled
[crtc
] = 1;
900 drm_update_vblank_count(dev
, crtc
);
903 spin_unlock_irqrestore(&dev
->vblank_time_lock
, irqflags2
);
906 if (!dev
->vblank_enabled
[crtc
]) {
907 atomic_dec(&dev
->vblank_refcount
[crtc
]);
911 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
915 EXPORT_SYMBOL(drm_vblank_get
);
918 * drm_vblank_put - give up ownership of vblank events
920 * @crtc: which counter to give up
922 * Release ownership of a given vblank counter, turning off interrupts
923 * if possible. Disable interrupts after drm_vblank_offdelay milliseconds.
925 void drm_vblank_put(struct drm_device
*dev
, int crtc
)
927 BUG_ON(atomic_read(&dev
->vblank_refcount
[crtc
]) == 0);
929 /* Last user schedules interrupt disable */
930 if (atomic_dec_and_test(&dev
->vblank_refcount
[crtc
]) &&
931 (drm_vblank_offdelay
> 0))
932 mod_timer(&dev
->vblank_disable_timer
,
933 jiffies
+ ((drm_vblank_offdelay
* DRM_HZ
)/1000));
935 EXPORT_SYMBOL(drm_vblank_put
);
937 void drm_vblank_off(struct drm_device
*dev
, int crtc
)
939 struct drm_pending_vblank_event
*e
, *t
;
941 unsigned long irqflags
;
944 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
945 vblank_disable_and_save(dev
, crtc
);
946 DRM_WAKEUP(&dev
->vbl_queue
[crtc
]);
948 /* Send any queued vblank events, lest the natives grow disquiet */
949 seq
= drm_vblank_count_and_time(dev
, crtc
, &now
);
950 list_for_each_entry_safe(e
, t
, &dev
->vblank_event_list
, base
.link
) {
953 DRM_DEBUG("Sending premature vblank event on disable: \
954 wanted %d, current %d\n",
955 e
->event
.sequence
, seq
);
957 e
->event
.sequence
= seq
;
958 e
->event
.tv_sec
= now
.tv_sec
;
959 e
->event
.tv_usec
= now
.tv_usec
;
960 drm_vblank_put(dev
, e
->pipe
);
961 list_move_tail(&e
->base
.link
, &e
->base
.file_priv
->event_list
);
962 wake_up_interruptible(&e
->base
.file_priv
->event_wait
);
963 trace_drm_vblank_event_delivered(e
->base
.pid
, e
->pipe
,
967 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
969 EXPORT_SYMBOL(drm_vblank_off
);
972 * drm_vblank_pre_modeset - account for vblanks across mode sets
974 * @crtc: CRTC in question
975 * @post: post or pre mode set?
977 * Account for vblank events across mode setting events, which will likely
978 * reset the hardware frame counter.
980 void drm_vblank_pre_modeset(struct drm_device
*dev
, int crtc
)
982 /* vblank is not initialized (IRQ not installed ?) */
986 * To avoid all the problems that might happen if interrupts
987 * were enabled/disabled around or between these calls, we just
988 * have the kernel take a reference on the CRTC (just once though
989 * to avoid corrupting the count if multiple, mismatch calls occur),
990 * so that interrupts remain enabled in the interim.
992 if (!dev
->vblank_inmodeset
[crtc
]) {
993 dev
->vblank_inmodeset
[crtc
] = 0x1;
994 if (drm_vblank_get(dev
, crtc
) == 0)
995 dev
->vblank_inmodeset
[crtc
] |= 0x2;
998 EXPORT_SYMBOL(drm_vblank_pre_modeset
);
1000 void drm_vblank_post_modeset(struct drm_device
*dev
, int crtc
)
1002 unsigned long irqflags
;
1004 if (dev
->vblank_inmodeset
[crtc
]) {
1005 spin_lock_irqsave(&dev
->vbl_lock
, irqflags
);
1006 dev
->vblank_disable_allowed
= 1;
1007 spin_unlock_irqrestore(&dev
->vbl_lock
, irqflags
);
1009 if (dev
->vblank_inmodeset
[crtc
] & 0x2)
1010 drm_vblank_put(dev
, crtc
);
1012 dev
->vblank_inmodeset
[crtc
] = 0;
1015 EXPORT_SYMBOL(drm_vblank_post_modeset
);
1018 * drm_modeset_ctl - handle vblank event counter changes across mode switch
1019 * @DRM_IOCTL_ARGS: standard ioctl arguments
1021 * Applications should call the %_DRM_PRE_MODESET and %_DRM_POST_MODESET
1022 * ioctls around modesetting so that any lost vblank events are accounted for.
1024 * Generally the counter will reset across mode sets. If interrupts are
1025 * enabled around this call, we don't have to do anything since the counter
1026 * will have already been incremented.
1028 int drm_modeset_ctl(struct drm_device
*dev
, void *data
,
1029 struct drm_file
*file_priv
)
1031 struct drm_modeset_ctl
*modeset
= data
;
1035 /* If drm_vblank_init() hasn't been called yet, just no-op */
1036 if (!dev
->num_crtcs
)
1039 crtc
= modeset
->crtc
;
1040 if (crtc
>= dev
->num_crtcs
) {
1045 switch (modeset
->cmd
) {
1046 case _DRM_PRE_MODESET
:
1047 drm_vblank_pre_modeset(dev
, crtc
);
1049 case _DRM_POST_MODESET
:
1050 drm_vblank_post_modeset(dev
, crtc
);
1061 static int drm_queue_vblank_event(struct drm_device
*dev
, int pipe
,
1062 union drm_wait_vblank
*vblwait
,
1063 struct drm_file
*file_priv
)
1065 struct drm_pending_vblank_event
*e
;
1067 unsigned long flags
;
1071 e
= kzalloc(sizeof *e
, GFP_KERNEL
);
1078 e
->base
.pid
= current
->pid
;
1079 e
->event
.base
.type
= DRM_EVENT_VBLANK
;
1080 e
->event
.base
.length
= sizeof e
->event
;
1081 e
->event
.user_data
= vblwait
->request
.signal
;
1082 e
->base
.event
= &e
->event
.base
;
1083 e
->base
.file_priv
= file_priv
;
1084 e
->base
.destroy
= (void (*) (struct drm_pending_event
*)) kfree
;
1086 spin_lock_irqsave(&dev
->event_lock
, flags
);
1088 if (file_priv
->event_space
< sizeof e
->event
) {
1093 file_priv
->event_space
-= sizeof e
->event
;
1094 seq
= drm_vblank_count_and_time(dev
, pipe
, &now
);
1096 if ((vblwait
->request
.type
& _DRM_VBLANK_NEXTONMISS
) &&
1097 (seq
- vblwait
->request
.sequence
) <= (1 << 23)) {
1098 vblwait
->request
.sequence
= seq
+ 1;
1099 vblwait
->reply
.sequence
= vblwait
->request
.sequence
;
1102 DRM_DEBUG("event on vblank count %d, current %d, crtc %d\n",
1103 vblwait
->request
.sequence
, seq
, pipe
);
1105 trace_drm_vblank_event_queued(current
->pid
, pipe
,
1106 vblwait
->request
.sequence
);
1108 e
->event
.sequence
= vblwait
->request
.sequence
;
1109 if ((seq
- vblwait
->request
.sequence
) <= (1 << 23)) {
1110 e
->event
.sequence
= seq
;
1111 e
->event
.tv_sec
= now
.tv_sec
;
1112 e
->event
.tv_usec
= now
.tv_usec
;
1113 drm_vblank_put(dev
, pipe
);
1114 list_add_tail(&e
->base
.link
, &e
->base
.file_priv
->event_list
);
1115 wake_up_interruptible(&e
->base
.file_priv
->event_wait
);
1116 vblwait
->reply
.sequence
= seq
;
1117 trace_drm_vblank_event_delivered(current
->pid
, pipe
,
1118 vblwait
->request
.sequence
);
1120 list_add_tail(&e
->base
.link
, &dev
->vblank_event_list
);
1121 vblwait
->reply
.sequence
= vblwait
->request
.sequence
;
1124 spin_unlock_irqrestore(&dev
->event_lock
, flags
);
1129 spin_unlock_irqrestore(&dev
->event_lock
, flags
);
1132 drm_vblank_put(dev
, pipe
);
1139 * \param inode device inode.
1140 * \param file_priv DRM file private.
1141 * \param cmd command.
1142 * \param data user argument, pointing to a drm_wait_vblank structure.
1143 * \return zero on success or a negative number on failure.
1145 * This function enables the vblank interrupt on the pipe requested, then
1146 * sleeps waiting for the requested sequence number to occur, and drops
1147 * the vblank interrupt refcount afterwards. (vblank irq disable follows that
1148 * after a timeout with no further vblank waits scheduled).
1150 int drm_wait_vblank(struct drm_device
*dev
, void *data
,
1151 struct drm_file
*file_priv
)
1153 union drm_wait_vblank
*vblwait
= data
;
1155 unsigned int flags
, seq
, crtc
, high_crtc
;
1157 if ((!drm_dev_to_irq(dev
)) || (!dev
->irq_enabled
))
1160 if (vblwait
->request
.type
& _DRM_VBLANK_SIGNAL
)
1163 if (vblwait
->request
.type
&
1164 ~(_DRM_VBLANK_TYPES_MASK
| _DRM_VBLANK_FLAGS_MASK
|
1165 _DRM_VBLANK_HIGH_CRTC_MASK
)) {
1166 DRM_ERROR("Unsupported type value 0x%x, supported mask 0x%x\n",
1167 vblwait
->request
.type
,
1168 (_DRM_VBLANK_TYPES_MASK
| _DRM_VBLANK_FLAGS_MASK
|
1169 _DRM_VBLANK_HIGH_CRTC_MASK
));
1173 flags
= vblwait
->request
.type
& _DRM_VBLANK_FLAGS_MASK
;
1174 high_crtc
= (vblwait
->request
.type
& _DRM_VBLANK_HIGH_CRTC_MASK
);
1176 crtc
= high_crtc
>> _DRM_VBLANK_HIGH_CRTC_SHIFT
;
1178 crtc
= flags
& _DRM_VBLANK_SECONDARY
? 1 : 0;
1179 if (crtc
>= dev
->num_crtcs
)
1182 ret
= drm_vblank_get(dev
, crtc
);
1184 DRM_DEBUG("failed to acquire vblank counter, %d\n", ret
);
1187 seq
= drm_vblank_count(dev
, crtc
);
1189 switch (vblwait
->request
.type
& _DRM_VBLANK_TYPES_MASK
) {
1190 case _DRM_VBLANK_RELATIVE
:
1191 vblwait
->request
.sequence
+= seq
;
1192 vblwait
->request
.type
&= ~_DRM_VBLANK_RELATIVE
;
1193 case _DRM_VBLANK_ABSOLUTE
:
1200 if (flags
& _DRM_VBLANK_EVENT
)
1201 return drm_queue_vblank_event(dev
, crtc
, vblwait
, file_priv
);
1203 if ((flags
& _DRM_VBLANK_NEXTONMISS
) &&
1204 (seq
- vblwait
->request
.sequence
) <= (1<<23)) {
1205 vblwait
->request
.sequence
= seq
+ 1;
1208 DRM_DEBUG("waiting on vblank count %d, crtc %d\n",
1209 vblwait
->request
.sequence
, crtc
);
1210 dev
->last_vblank_wait
[crtc
] = vblwait
->request
.sequence
;
1211 DRM_WAIT_ON(ret
, dev
->vbl_queue
[crtc
], 3 * DRM_HZ
,
1212 (((drm_vblank_count(dev
, crtc
) -
1213 vblwait
->request
.sequence
) <= (1 << 23)) ||
1214 !dev
->irq_enabled
));
1216 if (ret
!= -EINTR
) {
1219 vblwait
->reply
.sequence
= drm_vblank_count_and_time(dev
, crtc
, &now
);
1220 vblwait
->reply
.tval_sec
= now
.tv_sec
;
1221 vblwait
->reply
.tval_usec
= now
.tv_usec
;
1223 DRM_DEBUG("returning %d to client\n",
1224 vblwait
->reply
.sequence
);
1226 DRM_DEBUG("vblank wait interrupted by signal\n");
1230 drm_vblank_put(dev
, crtc
);
1234 void drm_handle_vblank_events(struct drm_device
*dev
, int crtc
)
1236 struct drm_pending_vblank_event
*e
, *t
;
1238 unsigned long flags
;
1241 seq
= drm_vblank_count_and_time(dev
, crtc
, &now
);
1243 spin_lock_irqsave(&dev
->event_lock
, flags
);
1245 list_for_each_entry_safe(e
, t
, &dev
->vblank_event_list
, base
.link
) {
1246 if (e
->pipe
!= crtc
)
1248 if ((seq
- e
->event
.sequence
) > (1<<23))
1251 DRM_DEBUG("vblank event on %d, current %d\n",
1252 e
->event
.sequence
, seq
);
1254 e
->event
.sequence
= seq
;
1255 e
->event
.tv_sec
= now
.tv_sec
;
1256 e
->event
.tv_usec
= now
.tv_usec
;
1257 drm_vblank_put(dev
, e
->pipe
);
1258 list_move_tail(&e
->base
.link
, &e
->base
.file_priv
->event_list
);
1259 wake_up_interruptible(&e
->base
.file_priv
->event_wait
);
1260 trace_drm_vblank_event_delivered(e
->base
.pid
, e
->pipe
,
1264 spin_unlock_irqrestore(&dev
->event_lock
, flags
);
1266 trace_drm_vblank_event(crtc
, seq
);
1270 * drm_handle_vblank - handle a vblank event
1272 * @crtc: where this event occurred
1274 * Drivers should call this routine in their vblank interrupt handlers to
1275 * update the vblank counter and send any signals that may be pending.
1277 bool drm_handle_vblank(struct drm_device
*dev
, int crtc
)
1281 struct timeval tvblank
;
1282 unsigned long irqflags
;
1284 if (!dev
->num_crtcs
)
1287 /* Need timestamp lock to prevent concurrent execution with
1288 * vblank enable/disable, as this would cause inconsistent
1289 * or corrupted timestamps and vblank counts.
1291 spin_lock_irqsave(&dev
->vblank_time_lock
, irqflags
);
1293 /* Vblank irq handling disabled. Nothing to do. */
1294 if (!dev
->vblank_enabled
[crtc
]) {
1295 spin_unlock_irqrestore(&dev
->vblank_time_lock
, irqflags
);
1299 /* Fetch corresponding timestamp for this vblank interval from
1300 * driver and store it in proper slot of timestamp ringbuffer.
1303 /* Get current timestamp and count. */
1304 vblcount
= atomic_read(&dev
->_vblank_count
[crtc
]);
1305 drm_get_last_vbltimestamp(dev
, crtc
, &tvblank
, DRM_CALLED_FROM_VBLIRQ
);
1307 /* Compute time difference to timestamp of last vblank */
1308 diff_ns
= timeval_to_ns(&tvblank
) -
1309 timeval_to_ns(&vblanktimestamp(dev
, crtc
, vblcount
));
1311 /* Update vblank timestamp and count if at least
1312 * DRM_REDUNDANT_VBLIRQ_THRESH_NS nanoseconds
1313 * difference between last stored timestamp and current
1314 * timestamp. A smaller difference means basically
1315 * identical timestamps. Happens if this vblank has
1316 * been already processed and this is a redundant call,
1317 * e.g., due to spurious vblank interrupts. We need to
1318 * ignore those for accounting.
1320 if (abs64(diff_ns
) > DRM_REDUNDANT_VBLIRQ_THRESH_NS
) {
1321 /* Store new timestamp in ringbuffer. */
1322 vblanktimestamp(dev
, crtc
, vblcount
+ 1) = tvblank
;
1324 /* Increment cooked vblank count. This also atomically commits
1325 * the timestamp computed above.
1327 smp_mb__before_atomic_inc();
1328 atomic_inc(&dev
->_vblank_count
[crtc
]);
1329 smp_mb__after_atomic_inc();
1331 DRM_DEBUG("crtc %d: Redundant vblirq ignored. diff_ns = %d\n",
1332 crtc
, (int) diff_ns
);
1335 DRM_WAKEUP(&dev
->vbl_queue
[crtc
]);
1336 drm_handle_vblank_events(dev
, crtc
);
1338 spin_unlock_irqrestore(&dev
->vblank_time_lock
, irqflags
);
1341 EXPORT_SYMBOL(drm_handle_vblank
);