blob: 273625a8503695f7c3c3506bfe30a828d79cd7a3 [file] [log] [blame]
Daniel Vetterf5752b32014-05-08 16:41:51 +02001/*
2 * drm_irq.c IRQ and vblank support
Linus Torvalds1da177e2005-04-16 15:20:36 -07003 *
4 * \author Rickard E. (Rik) Faith <faith@valinux.com>
5 * \author Gareth Hughes <gareth@valinux.com>
6 */
7
8/*
9 * Created: Fri Mar 19 14:30:16 1999 by faith@valinux.com
10 *
11 * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
12 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
13 * All Rights Reserved.
14 *
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:
21 *
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
24 * Software.
25 *
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.
33 */
34
David Howells760285e2012-10-02 18:01:07 +010035#include <drm/drmP.h>
Jesse Barnesac2874b2010-07-01 16:47:31 -070036#include "drm_trace.h"
Daniel Vetter18882992014-09-10 08:16:10 +020037#include "drm_internal.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070038
39#include <linux/interrupt.h> /* For task queue support */
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090040#include <linux/slab.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070041
Dave Airlie28d52042009-09-21 14:33:58 +100042#include <linux/vgaarb.h>
Paul Gortmaker2d1a8a42011-08-30 18:16:33 -040043#include <linux/export.h>
Mario Kleiner27641c32010-10-23 04:20:23 +020044
Mario Kleiner27641c32010-10-23 04:20:23 +020045/* Retry timestamp calculation up to 3 times to satisfy
46 * drm_timestamp_precision before giving up.
47 */
48#define DRM_TIMESTAMP_MAXRETRIES 3
49
50/* Threshold in nanoseconds for detection of redundant
51 * vblank irq in drm_handle_vblank(). 1 msec should be ok.
52 */
53#define DRM_REDUNDANT_VBLIRQ_THRESH_NS 1000000
54
Daniel Vetterfb446a12014-09-10 17:36:10 +020055static bool
Thierry Redingcc1ef112015-08-12 17:00:31 +020056drm_get_last_vbltimestamp(struct drm_device *dev, unsigned int pipe,
Daniel Vetterfb446a12014-09-10 17:36:10 +020057 struct timeval *tvblank, unsigned flags);
58
Daniel Vetter18882992014-09-10 08:16:10 +020059static unsigned int drm_timestamp_precision = 20; /* Default to 20 usecs. */
60
61/*
62 * Default to use monotonic timestamps for wait-for-vblank and page-flip
63 * complete events.
64 */
65unsigned int drm_timestamp_monotonic = 1;
66
67static int drm_vblank_offdelay = 5000; /* Default to 5000 msecs. */
68
69module_param_named(vblankoffdelay, drm_vblank_offdelay, int, 0600);
70module_param_named(timestamp_precision_usec, drm_timestamp_precision, int, 0600);
71module_param_named(timestamp_monotonic, drm_timestamp_monotonic, int, 0600);
Dan Carpenterd9d8c4c2016-01-08 14:00:45 +030072MODULE_PARM_DESC(vblankoffdelay, "Delay until vblank irq auto-disable [msecs] (0: never disable, <0: disable immediately)");
73MODULE_PARM_DESC(timestamp_precision_usec, "Max. error on timestamps [usecs]");
74MODULE_PARM_DESC(timestamp_monotonic, "Use monotonic timestamps");
Daniel Vetter18882992014-09-10 08:16:10 +020075
Ville Syrjälä1da248a2015-09-14 22:43:42 +030076static void store_vblank(struct drm_device *dev, unsigned int pipe,
Daniel Vetter209e4dbc2015-08-07 12:31:17 +020077 u32 vblank_count_inc,
Ville Syrjälä4dfd6482015-09-14 22:43:51 +030078 struct timeval *t_vblank, u32 last)
Daniel Vetter99264a62015-04-15 19:34:43 +020079{
Ville Syrjälä1da248a2015-09-14 22:43:42 +030080 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
Daniel Vetter99264a62015-04-15 19:34:43 +020081
82 assert_spin_locked(&dev->vblank_time_lock);
83
Ville Syrjälä4dfd6482015-09-14 22:43:51 +030084 vblank->last = last;
85
Matthew Auldd4055a92016-05-10 15:21:28 +010086 write_seqlock(&vblank->seqlock);
87 vblank->time = *t_vblank;
Daniel Vetter99264a62015-04-15 19:34:43 +020088 vblank->count += vblank_count_inc;
Matthew Auldd4055a92016-05-10 15:21:28 +010089 write_sequnlock(&vblank->seqlock);
Daniel Vetter99264a62015-04-15 19:34:43 +020090}
91
Daniel Vetter00edbe12016-05-31 23:11:14 +020092/*
Ville Syrjälä4dfd6482015-09-14 22:43:51 +030093 * Reset the stored timestamp for the current vblank count to correspond
94 * to the last vblank occurred.
95 *
Daniel Vetter2d1e3312016-11-14 10:02:54 +010096 * Only to be called from drm_crtc_vblank_on().
Ville Syrjälä4dfd6482015-09-14 22:43:51 +030097 *
98 * Note: caller must hold dev->vbl_lock since this reads & writes
99 * device vblank fields.
100 */
101static void drm_reset_vblank_timestamp(struct drm_device *dev, unsigned int pipe)
102{
103 u32 cur_vblank;
104 bool rc;
105 struct timeval t_vblank;
106 int count = DRM_TIMESTAMP_MAXRETRIES;
107
108 spin_lock(&dev->vblank_time_lock);
109
110 /*
111 * sample the current counter to avoid random jumps
112 * when drm_vblank_enable() applies the diff
113 */
114 do {
115 cur_vblank = dev->driver->get_vblank_counter(dev, pipe);
116 rc = drm_get_last_vbltimestamp(dev, pipe, &t_vblank, 0);
117 } while (cur_vblank != dev->driver->get_vblank_counter(dev, pipe) && --count > 0);
118
119 /*
120 * Only reinitialize corresponding vblank timestamp if high-precision query
121 * available and didn't fail. Otherwise reinitialize delayed at next vblank
122 * interrupt and assign 0 for now, to mark the vblanktimestamp as invalid.
123 */
124 if (!rc)
125 t_vblank = (struct timeval) {0, 0};
126
127 /*
128 * +1 to make sure user will never see the same
129 * vblank counter value before and after a modeset
130 */
131 store_vblank(dev, pipe, 1, &t_vblank, cur_vblank);
132
133 spin_unlock(&dev->vblank_time_lock);
134}
135
Daniel Vetter00edbe12016-05-31 23:11:14 +0200136/*
Ville Syrjälä13b030a2014-08-06 14:49:47 +0300137 * Call back into the driver to update the appropriate vblank counter
Ville Syrjälä1da248a2015-09-14 22:43:42 +0300138 * (specified by @pipe). Deal with wraparound, if it occurred, and
Ville Syrjälä13b030a2014-08-06 14:49:47 +0300139 * update the last read value so we can deal with wraparound on the next
140 * call if necessary.
141 *
142 * Only necessary when going from off->on, to account for frames we
143 * didn't get an interrupt for.
144 *
145 * Note: caller must hold dev->vbl_lock since this reads & writes
146 * device vblank fields.
147 */
Ville Syrjäläa6e610d2015-09-14 22:43:47 +0300148static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe,
149 unsigned long flags)
Ville Syrjälä13b030a2014-08-06 14:49:47 +0300150{
Thierry Redingcc1ef112015-08-12 17:00:31 +0200151 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
Daniel Vetter99264a62015-04-15 19:34:43 +0200152 u32 cur_vblank, diff;
Daniel Vetterfb446a12014-09-10 17:36:10 +0200153 bool rc;
Ville Syrjälä13b030a2014-08-06 14:49:47 +0300154 struct timeval t_vblank;
Ville Syrjäläfacfb062015-09-14 22:43:48 +0300155 int count = DRM_TIMESTAMP_MAXRETRIES;
Ville Syrjälä4dfd6482015-09-14 22:43:51 +0300156 int framedur_ns = vblank->framedur_ns;
Ville Syrjälä13b030a2014-08-06 14:49:47 +0300157
158 /*
159 * Interrupts were disabled prior to this call, so deal with counter
160 * wrap if needed.
Michel Dänzer5ceecb22015-05-26 17:53:38 +0900161 * NOTE! It's possible we lost a full dev->max_vblank_count + 1 events
Ville Syrjälä13b030a2014-08-06 14:49:47 +0300162 * here if the register is small or we had vblank interrupts off for
163 * a long time.
164 *
165 * We repeat the hardware vblank counter & timestamp query until
166 * we get consistent results. This to prevent races between gpu
167 * updating its hardware counter while we are retrieving the
168 * corresponding vblank timestamp.
169 */
170 do {
Thierry Redingcc1ef112015-08-12 17:00:31 +0200171 cur_vblank = dev->driver->get_vblank_counter(dev, pipe);
Ville Syrjäläa6e610d2015-09-14 22:43:47 +0300172 rc = drm_get_last_vbltimestamp(dev, pipe, &t_vblank, flags);
Ville Syrjäläfacfb062015-09-14 22:43:48 +0300173 } while (cur_vblank != dev->driver->get_vblank_counter(dev, pipe) && --count > 0);
Ville Syrjälä13b030a2014-08-06 14:49:47 +0300174
Ville Syrjälä4dfd6482015-09-14 22:43:51 +0300175 if (dev->max_vblank_count != 0) {
176 /* trust the hw counter when it's around */
177 diff = (cur_vblank - vblank->last) & dev->max_vblank_count;
178 } else if (rc && framedur_ns) {
179 const struct timeval *t_old;
180 u64 diff_ns;
Ville Syrjälä13b030a2014-08-06 14:49:47 +0300181
Matthew Auldd4055a92016-05-10 15:21:28 +0100182 t_old = &vblank->time;
Ville Syrjälä4dfd6482015-09-14 22:43:51 +0300183 diff_ns = timeval_to_ns(&t_vblank) - timeval_to_ns(t_old);
184
185 /*
186 * Figure out how many vblanks we've missed based
187 * on the difference in the timestamps and the
188 * frame/field duration.
189 */
190 diff = DIV_ROUND_CLOSEST_ULL(diff_ns, framedur_ns);
191
192 if (diff == 0 && flags & DRM_CALLED_FROM_VBLIRQ)
Ville Syrjälä235fabe2015-10-09 22:57:37 +0300193 DRM_DEBUG_VBL("crtc %u: Redundant vblirq ignored."
194 " diff_ns = %lld, framedur_ns = %d)\n",
195 pipe, (long long) diff_ns, framedur_ns);
Ville Syrjälä4dfd6482015-09-14 22:43:51 +0300196 } else {
197 /* some kind of default for drivers w/o accurate vbl timestamping */
198 diff = (flags & DRM_CALLED_FROM_VBLIRQ) != 0;
Ville Syrjälä13b030a2014-08-06 14:49:47 +0300199 }
200
Mario Kleiner99b8e712016-02-12 20:30:28 +0100201 /*
Mario Kleinerc61934e2016-02-12 20:30:29 +0100202 * Within a drm_vblank_pre_modeset - drm_vblank_post_modeset
203 * interval? If so then vblank irqs keep running and it will likely
204 * happen that the hardware vblank counter is not trustworthy as it
205 * might reset at some point in that interval and vblank timestamps
206 * are not trustworthy either in that interval. Iow. this can result
207 * in a bogus diff >> 1 which must be avoided as it would cause
208 * random large forward jumps of the software vblank counter.
209 */
210 if (diff > 1 && (vblank->inmodeset & 0x2)) {
211 DRM_DEBUG_VBL("clamping vblank bump to 1 on crtc %u: diffr=%u"
212 " due to pre-modeset.\n", pipe, diff);
213 diff = 1;
214 }
215
Ville Syrjälä235fabe2015-10-09 22:57:37 +0300216 DRM_DEBUG_VBL("updating vblank count on crtc %u:"
217 " current=%u, diff=%u, hw=%u hw_last=%u\n",
218 pipe, vblank->count, diff, cur_vblank, vblank->last);
Ville Syrjälä13b030a2014-08-06 14:49:47 +0300219
Ville Syrjälä4dfd6482015-09-14 22:43:51 +0300220 if (diff == 0) {
221 WARN_ON_ONCE(cur_vblank != vblank->last);
Mario Kleinerda8f4392014-09-13 18:25:54 +0200222 return;
Ville Syrjälä4dfd6482015-09-14 22:43:51 +0300223 }
Mario Kleinerda8f4392014-09-13 18:25:54 +0200224
Daniel Vetter99264a62015-04-15 19:34:43 +0200225 /*
226 * Only reinitialize corresponding vblank timestamp if high-precision query
Ville Syrjäläfa4270d2015-09-30 19:21:34 +0300227 * available and didn't fail, or we were called from the vblank interrupt.
228 * Otherwise reinitialize delayed at next vblank interrupt and assign 0
229 * for now, to mark the vblanktimestamp as invalid.
Ville Syrjälä13b030a2014-08-06 14:49:47 +0300230 */
Ville Syrjäläfa4270d2015-09-30 19:21:34 +0300231 if (!rc && (flags & DRM_CALLED_FROM_VBLIRQ) == 0)
Mario Kleinerd66a1e32015-05-04 06:29:46 +0200232 t_vblank = (struct timeval) {0, 0};
233
Ville Syrjälä4dfd6482015-09-14 22:43:51 +0300234 store_vblank(dev, pipe, diff, &t_vblank, cur_vblank);
Ville Syrjälä13b030a2014-08-06 14:49:47 +0300235}
236
Daniel Vetterd6b0f622016-11-14 10:02:53 +0100237static u32 drm_vblank_count(struct drm_device *dev, unsigned int pipe)
238{
239 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
240
241 if (WARN_ON(pipe >= dev->num_crtcs))
242 return 0;
243
244 return vblank->count;
245}
246
Maarten Lankhorstaf61d5c2016-05-17 15:07:44 +0200247/**
248 * drm_accurate_vblank_count - retrieve the master vblank counter
249 * @crtc: which counter to retrieve
250 *
251 * This function is similar to @drm_crtc_vblank_count but this
252 * function interpolates to handle a race with vblank irq's.
253 *
254 * This is mostly useful for hardware that can obtain the scanout
255 * position, but doesn't have a frame counter.
256 */
257u32 drm_accurate_vblank_count(struct drm_crtc *crtc)
258{
259 struct drm_device *dev = crtc->dev;
260 unsigned int pipe = drm_crtc_index(crtc);
261 u32 vblank;
262 unsigned long flags;
263
264 WARN(!dev->driver->get_vblank_timestamp,
265 "This function requires support for accurate vblank timestamps.");
266
267 spin_lock_irqsave(&dev->vblank_time_lock, flags);
268
269 drm_update_vblank_count(dev, pipe, 0);
270 vblank = drm_vblank_count(dev, pipe);
271
272 spin_unlock_irqrestore(&dev->vblank_time_lock, flags);
273
274 return vblank;
275}
276EXPORT_SYMBOL(drm_accurate_vblank_count);
277
Mario Kleiner27641c32010-10-23 04:20:23 +0200278/*
Mario Kleiner27641c32010-10-23 04:20:23 +0200279 * Disable vblank irq's on crtc, make sure that last vblank count
280 * of hardware and corresponding consistent software vblank counter
281 * are preserved, even if there are any spurious vblank irq's after
282 * disable.
283 */
Thierry Redingcc1ef112015-08-12 17:00:31 +0200284static void vblank_disable_and_save(struct drm_device *dev, unsigned int pipe)
Mario Kleiner27641c32010-10-23 04:20:23 +0200285{
Thierry Redingcc1ef112015-08-12 17:00:31 +0200286 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
Mario Kleiner27641c32010-10-23 04:20:23 +0200287 unsigned long irqflags;
Mario Kleiner27641c32010-10-23 04:20:23 +0200288
289 /* Prevent vblank irq processing while disabling vblank irqs,
290 * so no updates of timestamps or count can happen after we've
291 * disabled. Needed to prevent races in case of delayed irq's.
Mario Kleiner27641c32010-10-23 04:20:23 +0200292 */
Mario Kleiner27641c32010-10-23 04:20:23 +0200293 spin_lock_irqsave(&dev->vblank_time_lock, irqflags);
294
Ville Syrjälä812e7462014-08-06 14:49:48 +0300295 /*
Laurent Pincharteb2ed662015-01-29 01:09:24 +0200296 * Only disable vblank interrupts if they're enabled. This avoids
297 * calling the ->disable_vblank() operation in atomic context with the
298 * hardware potentially runtime suspended.
299 */
300 if (vblank->enabled) {
Thierry Redingcc1ef112015-08-12 17:00:31 +0200301 dev->driver->disable_vblank(dev, pipe);
Laurent Pincharteb2ed662015-01-29 01:09:24 +0200302 vblank->enabled = false;
303 }
Mario Kleiner27641c32010-10-23 04:20:23 +0200304
Ville Syrjälä4dfd6482015-09-14 22:43:51 +0300305 /*
306 * Always update the count and timestamp to maintain the
307 * appearance that the counter has been ticking all along until
308 * this time. This makes the count account for the entire time
Daniel Vetter2d1e3312016-11-14 10:02:54 +0100309 * between drm_crtc_vblank_on() and drm_crtc_vblank_off().
Mario Kleiner27641c32010-10-23 04:20:23 +0200310 */
Ville Syrjälä4dfd6482015-09-14 22:43:51 +0300311 drm_update_vblank_count(dev, pipe, 0);
Mario Kleiner27641c32010-10-23 04:20:23 +0200312
Mario Kleiner27641c32010-10-23 04:20:23 +0200313 spin_unlock_irqrestore(&dev->vblank_time_lock, irqflags);
Mario Kleiner27641c32010-10-23 04:20:23 +0200314}
315
Jesse Barnes0a3e67a2008-09-30 12:14:26 -0700316static void vblank_disable_fn(unsigned long arg)
317{
Ville Syrjäläe69595c2014-02-19 19:36:08 +0200318 struct drm_vblank_crtc *vblank = (void *)arg;
319 struct drm_device *dev = vblank->dev;
Thierry Redingcc1ef112015-08-12 17:00:31 +0200320 unsigned int pipe = vblank->pipe;
Jesse Barnes0a3e67a2008-09-30 12:14:26 -0700321 unsigned long irqflags;
Jesse Barnes0a3e67a2008-09-30 12:14:26 -0700322
Ville Syrjäläe69595c2014-02-19 19:36:08 +0200323 spin_lock_irqsave(&dev->vbl_lock, irqflags);
324 if (atomic_read(&vblank->refcount) == 0 && vblank->enabled) {
Thierry Redingcc1ef112015-08-12 17:00:31 +0200325 DRM_DEBUG("disabling vblank on crtc %u\n", pipe);
326 vblank_disable_and_save(dev, pipe);
Jesse Barnes0a3e67a2008-09-30 12:14:26 -0700327 }
Ville Syrjäläe69595c2014-02-19 19:36:08 +0200328 spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
Jesse Barnes0a3e67a2008-09-30 12:14:26 -0700329}
330
Daniel Vetterf5752b32014-05-08 16:41:51 +0200331/**
332 * drm_vblank_cleanup - cleanup vblank support
333 * @dev: DRM device
334 *
335 * This function cleans up any resources allocated in drm_vblank_init.
336 */
Keith Packard52440212008-11-18 09:30:25 -0800337void drm_vblank_cleanup(struct drm_device *dev)
Jesse Barnes0a3e67a2008-09-30 12:14:26 -0700338{
Thierry Redingcc1ef112015-08-12 17:00:31 +0200339 unsigned int pipe;
Ville Syrjäläe69595c2014-02-19 19:36:08 +0200340
Jesse Barnes0a3e67a2008-09-30 12:14:26 -0700341 /* Bail if the driver didn't call drm_vblank_init() */
342 if (dev->num_crtcs == 0)
343 return;
344
Thierry Redingcc1ef112015-08-12 17:00:31 +0200345 for (pipe = 0; pipe < dev->num_crtcs; pipe++) {
346 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
Ville Syrjälä8a51d5b2014-08-06 14:49:50 +0300347
Daniel Vetter3bff93d2015-02-22 15:11:19 +0100348 WARN_ON(vblank->enabled &&
349 drm_core_check_feature(dev, DRIVER_MODESET));
Mario Kleiner2368ffb2014-08-06 03:22:46 +0200350
Daniel Vetter3bff93d2015-02-22 15:11:19 +0100351 del_timer_sync(&vblank->disable_timer);
Ville Syrjäläe69595c2014-02-19 19:36:08 +0200352 }
Jesse Barnes0a3e67a2008-09-30 12:14:26 -0700353
Ville Syrjälä5380e922013-10-04 14:53:36 +0300354 kfree(dev->vblank);
Jesse Barnes0a3e67a2008-09-30 12:14:26 -0700355
356 dev->num_crtcs = 0;
357}
Jerome Glissee77cef92010-01-07 15:39:13 +0100358EXPORT_SYMBOL(drm_vblank_cleanup);
Jesse Barnes0a3e67a2008-09-30 12:14:26 -0700359
Daniel Vetterf5752b32014-05-08 16:41:51 +0200360/**
361 * drm_vblank_init - initialize vblank support
Thierry Redingcc1ef112015-08-12 17:00:31 +0200362 * @dev: DRM device
363 * @num_crtcs: number of CRTCs supported by @dev
Daniel Vetterf5752b32014-05-08 16:41:51 +0200364 *
365 * This function initializes vblank support for @num_crtcs display pipelines.
366 *
367 * Returns:
368 * Zero on success or a negative error code on failure.
369 */
Thierry Redingcc1ef112015-08-12 17:00:31 +0200370int drm_vblank_init(struct drm_device *dev, unsigned int num_crtcs)
Jesse Barnes0a3e67a2008-09-30 12:14:26 -0700371{
Thierry Redingcc1ef112015-08-12 17:00:31 +0200372 int ret = -ENOMEM;
373 unsigned int i;
Jesse Barnes0a3e67a2008-09-30 12:14:26 -0700374
Jesse Barnes0a3e67a2008-09-30 12:14:26 -0700375 spin_lock_init(&dev->vbl_lock);
Mario Kleiner27641c32010-10-23 04:20:23 +0200376 spin_lock_init(&dev->vblank_time_lock);
377
Jesse Barnes0a3e67a2008-09-30 12:14:26 -0700378 dev->num_crtcs = num_crtcs;
379
Ville Syrjälä5380e922013-10-04 14:53:36 +0300380 dev->vblank = kcalloc(num_crtcs, sizeof(*dev->vblank), GFP_KERNEL);
381 if (!dev->vblank)
Jesse Barnes0a3e67a2008-09-30 12:14:26 -0700382 goto err;
383
Ville Syrjäläe69595c2014-02-19 19:36:08 +0200384 for (i = 0; i < num_crtcs; i++) {
Ville Syrjälä8a51d5b2014-08-06 14:49:50 +0300385 struct drm_vblank_crtc *vblank = &dev->vblank[i];
386
387 vblank->dev = dev;
Thierry Redingcc1ef112015-08-12 17:00:31 +0200388 vblank->pipe = i;
Ville Syrjälä8a51d5b2014-08-06 14:49:50 +0300389 init_waitqueue_head(&vblank->queue);
390 setup_timer(&vblank->disable_timer, vblank_disable_fn,
391 (unsigned long)vblank);
Matthew Auldd4055a92016-05-10 15:21:28 +0100392 seqlock_init(&vblank->seqlock);
Ville Syrjäläe69595c2014-02-19 19:36:08 +0200393 }
Mario Kleiner27641c32010-10-23 04:20:23 +0200394
Mario Kleiner8f6fce02013-10-30 05:13:06 +0100395 DRM_INFO("Supports vblank timestamp caching Rev 2 (21.10.2013).\n");
Mario Kleiner27641c32010-10-23 04:20:23 +0200396
397 /* Driver specific high-precision vblank timestamping supported? */
398 if (dev->driver->get_vblank_timestamp)
399 DRM_INFO("Driver supports precise vblank timestamp query.\n");
400 else
401 DRM_INFO("No driver support for vblank timestamp query.\n");
402
Mario Kleiner5a8b21b2015-05-04 06:29:45 +0200403 /* Must have precise timestamping for reliable vblank instant disable */
404 if (dev->vblank_disable_immediate && !dev->driver->get_vblank_timestamp) {
405 dev->vblank_disable_immediate = false;
406 DRM_INFO("Setting vblank_disable_immediate to false because "
407 "get_vblank_timestamp == NULL\n");
408 }
409
Jesse Barnes0a3e67a2008-09-30 12:14:26 -0700410 return 0;
411
412err:
Mario Kleiner79a093ae2014-08-06 03:22:44 +0200413 dev->num_crtcs = 0;
Jesse Barnes0a3e67a2008-09-30 12:14:26 -0700414 return ret;
415}
416EXPORT_SYMBOL(drm_vblank_init);
417
Dave Airlie28d52042009-09-21 14:33:58 +1000418static void drm_irq_vgaarb_nokms(void *cookie, bool state)
419{
420 struct drm_device *dev = cookie;
421
422 if (dev->driver->vgaarb_irq) {
423 dev->driver->vgaarb_irq(dev, state);
424 return;
425 }
426
427 if (!dev->irq_enabled)
428 return;
429
Joonyoung Shim5037f8a2011-08-04 05:41:01 +0000430 if (state) {
431 if (dev->driver->irq_uninstall)
432 dev->driver->irq_uninstall(dev);
433 } else {
434 if (dev->driver->irq_preinstall)
435 dev->driver->irq_preinstall(dev);
436 if (dev->driver->irq_postinstall)
437 dev->driver->irq_postinstall(dev);
Dave Airlie28d52042009-09-21 14:33:58 +1000438 }
439}
440
Linus Torvalds1da177e2005-04-16 15:20:36 -0700441/**
Daniel Vetterf5752b32014-05-08 16:41:51 +0200442 * drm_irq_install - install IRQ handler
443 * @dev: DRM device
444 * @irq: IRQ number to install the handler for
Linus Torvalds1da177e2005-04-16 15:20:36 -0700445 *
Jesse Barnes0a3e67a2008-09-30 12:14:26 -0700446 * Initializes the IRQ related data. Installs the handler, calling the driver
Daniel Vetterf5752b32014-05-08 16:41:51 +0200447 * irq_preinstall() and irq_postinstall() functions before and after the
448 * installation.
449 *
450 * This is the simplified helper interface provided for drivers with no special
451 * needs. Drivers which need to install interrupt handlers for multiple
452 * interrupts must instead set drm_device->irq_enabled to signal the DRM core
453 * that vblank interrupts are available.
454 *
455 * Returns:
456 * Zero on success or a negative error code on failure.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700457 */
Daniel Vetterbb0f1b52013-11-03 21:09:27 +0100458int drm_irq_install(struct drm_device *dev, int irq)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700459{
Laurent Pinchart4a1b0712012-05-17 13:27:21 +0200460 int ret;
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000461 unsigned long sh_flags = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700462
463 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
464 return -EINVAL;
465
Daniel Vetter7c1a38e2013-12-16 11:21:15 +0100466 if (irq == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700467 return -EINVAL;
468
Linus Torvalds1da177e2005-04-16 15:20:36 -0700469 /* Driver must have been initialized */
Daniel Vettere090c532013-11-03 20:27:05 +0100470 if (!dev->dev_private)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700471 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700472
Daniel Vettere090c532013-11-03 20:27:05 +0100473 if (dev->irq_enabled)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700474 return -EBUSY;
Ville Syrjälä44238432013-10-04 14:53:37 +0300475 dev->irq_enabled = true;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700476
Daniel Vetter7c1a38e2013-12-16 11:21:15 +0100477 DRM_DEBUG("irq=%d\n", irq);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700478
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000479 /* Before installing handler */
Joonyoung Shim5037f8a2011-08-04 05:41:01 +0000480 if (dev->driver->irq_preinstall)
481 dev->driver->irq_preinstall(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700482
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000483 /* Install handler */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700484 if (drm_core_check_feature(dev, DRIVER_IRQ_SHARED))
Thomas Gleixner935f6e32006-07-01 19:29:34 -0700485 sh_flags = IRQF_SHARED;
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000486
Daniel Vetter7c1a38e2013-12-16 11:21:15 +0100487 ret = request_irq(irq, dev->driver->irq_handler,
Daniel Vetter5829d182013-11-03 21:48:48 +0100488 sh_flags, dev->driver->name, dev);
Jesse Barnes9bfbd5c2008-09-15 15:00:33 -0700489
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000490 if (ret < 0) {
Ville Syrjälä44238432013-10-04 14:53:37 +0300491 dev->irq_enabled = false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700492 return ret;
493 }
494
Daniel Vetterfa538642016-08-03 21:11:10 +0200495 if (drm_core_check_feature(dev, DRIVER_LEGACY))
Dave Airlie28d52042009-09-21 14:33:58 +1000496 vga_client_register(dev->pdev, (void *)dev, drm_irq_vgaarb_nokms, NULL);
497
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000498 /* After installing handler */
Joonyoung Shim5037f8a2011-08-04 05:41:01 +0000499 if (dev->driver->irq_postinstall)
500 ret = dev->driver->irq_postinstall(dev);
501
Jesse Barnes0a3e67a2008-09-30 12:14:26 -0700502 if (ret < 0) {
Ville Syrjälä44238432013-10-04 14:53:37 +0300503 dev->irq_enabled = false;
Daniel Vetterfa538642016-08-03 21:11:10 +0200504 if (drm_core_check_feature(dev, DRIVER_LEGACY))
Joonyoung Shime1c44ac2011-08-04 05:41:00 +0000505 vga_client_register(dev->pdev, NULL, NULL, NULL);
Daniel Vetter7c1a38e2013-12-16 11:21:15 +0100506 free_irq(irq, dev);
507 } else {
508 dev->irq = irq;
Jesse Barnes0a3e67a2008-09-30 12:14:26 -0700509 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700510
Jesse Barnes0a3e67a2008-09-30 12:14:26 -0700511 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700512}
Jesse Barnes0a3e67a2008-09-30 12:14:26 -0700513EXPORT_SYMBOL(drm_irq_install);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700514
515/**
Daniel Vetterf5752b32014-05-08 16:41:51 +0200516 * drm_irq_uninstall - uninstall the IRQ handler
517 * @dev: DRM device
Linus Torvalds1da177e2005-04-16 15:20:36 -0700518 *
Daniel Vetterf5752b32014-05-08 16:41:51 +0200519 * Calls the driver's irq_uninstall() function and unregisters the IRQ handler.
520 * This should only be called by drivers which used drm_irq_install() to set up
521 * their interrupt handler. Other drivers must only reset
522 * drm_device->irq_enabled to false.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700523 *
Daniel Vetterf5752b32014-05-08 16:41:51 +0200524 * Note that for kernel modesetting drivers it is a bug if this function fails.
525 * The sanity checks are only to catch buggy user modesetting drivers which call
526 * the same function through an ioctl.
527 *
528 * Returns:
529 * Zero on success or a negative error code on failure.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530 */
Mario Kleiner27641c32010-10-23 04:20:23 +0200531int drm_irq_uninstall(struct drm_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700532{
Jesse Barnesdc1336f2009-01-06 10:21:24 -0800533 unsigned long irqflags;
Ville Syrjälä44238432013-10-04 14:53:37 +0300534 bool irq_enabled;
535 int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700536
537 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
538 return -EINVAL;
539
Linus Torvalds1da177e2005-04-16 15:20:36 -0700540 irq_enabled = dev->irq_enabled;
Ville Syrjälä44238432013-10-04 14:53:37 +0300541 dev->irq_enabled = false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542
Jesse Barnesdc1336f2009-01-06 10:21:24 -0800543 /*
Daniel Vetter3bff93d2015-02-22 15:11:19 +0100544 * Wake up any waiters so they don't hang. This is just to paper over
Frank Binnsc78d1ca2016-06-24 11:15:37 +0100545 * issues for UMS drivers which aren't in full control of their
Daniel Vetter3bff93d2015-02-22 15:11:19 +0100546 * vblank/irq handling. KMS drivers must ensure that vblanks are all
547 * disabled when uninstalling the irq handler.
Jesse Barnesdc1336f2009-01-06 10:21:24 -0800548 */
Ben Skeggsbde48892011-07-04 12:52:27 +1000549 if (dev->num_crtcs) {
550 spin_lock_irqsave(&dev->vbl_lock, irqflags);
551 for (i = 0; i < dev->num_crtcs; i++) {
Ville Syrjälä8a51d5b2014-08-06 14:49:50 +0300552 struct drm_vblank_crtc *vblank = &dev->vblank[i];
553
Daniel Vetter3bff93d2015-02-22 15:11:19 +0100554 if (!vblank->enabled)
555 continue;
556
557 WARN_ON(drm_core_check_feature(dev, DRIVER_MODESET));
558
559 vblank_disable_and_save(dev, i);
Ville Syrjälä8a51d5b2014-08-06 14:49:50 +0300560 wake_up(&vblank->queue);
Ben Skeggsbde48892011-07-04 12:52:27 +1000561 }
562 spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
Jesse Barnesdc1336f2009-01-06 10:21:24 -0800563 }
Jesse Barnesdc1336f2009-01-06 10:21:24 -0800564
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000565 if (!irq_enabled)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700566 return -EINVAL;
567
Daniel Vetter7c1a38e2013-12-16 11:21:15 +0100568 DRM_DEBUG("irq=%d\n", dev->irq);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700569
Daniel Vetterfa538642016-08-03 21:11:10 +0200570 if (drm_core_check_feature(dev, DRIVER_LEGACY))
Dave Airlie28d52042009-09-21 14:33:58 +1000571 vga_client_register(dev->pdev, NULL, NULL, NULL);
572
Joonyoung Shim5037f8a2011-08-04 05:41:01 +0000573 if (dev->driver->irq_uninstall)
574 dev->driver->irq_uninstall(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700575
Daniel Vetter7c1a38e2013-12-16 11:21:15 +0100576 free_irq(dev->irq, dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700577
578 return 0;
579}
580EXPORT_SYMBOL(drm_irq_uninstall);
581
Daniel Vetterf5752b32014-05-08 16:41:51 +0200582/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700583 * IRQ control ioctl.
584 *
585 * \param inode device inode.
Eric Anholt6c340ea2007-08-25 20:23:09 +1000586 * \param file_priv DRM file private.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700587 * \param cmd command.
588 * \param arg user argument, pointing to a drm_control structure.
589 * \return zero on success or a negative number on failure.
590 *
591 * Calls irq_install() or irq_uninstall() according to \p arg.
592 */
Eric Anholtc153f452007-09-03 12:06:45 +1000593int drm_control(struct drm_device *dev, void *data,
594 struct drm_file *file_priv)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700595{
Eric Anholtc153f452007-09-03 12:06:45 +1000596 struct drm_control *ctl = data;
Daniel Vettera319c1a2013-11-03 21:09:15 +0100597 int ret = 0, irq;
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000598
Mario Kleiner27641c32010-10-23 04:20:23 +0200599 /* if we haven't irq we fallback for compatibility reasons -
600 * this used to be a separate function in drm_dma.h
601 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700602
Daniel Vetter22471cf2013-11-03 20:02:50 +0100603 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
604 return 0;
Daniel Vetterfa538642016-08-03 21:11:10 +0200605 if (!drm_core_check_feature(dev, DRIVER_LEGACY))
Daniel Vetter22471cf2013-11-03 20:02:50 +0100606 return 0;
Frank Binnsc78d1ca2016-06-24 11:15:37 +0100607 /* UMS was only ever supported on pci devices. */
Daniel Vetter22471cf2013-11-03 20:02:50 +0100608 if (WARN_ON(!dev->pdev))
609 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700610
Eric Anholtc153f452007-09-03 12:06:45 +1000611 switch (ctl->func) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700612 case DRM_INST_HANDLER:
Daniel Vettera319c1a2013-11-03 21:09:15 +0100613 irq = dev->pdev->irq;
614
Linus Torvalds1da177e2005-04-16 15:20:36 -0700615 if (dev->if_version < DRM_IF_VERSION(1, 2) &&
Daniel Vettera319c1a2013-11-03 21:09:15 +0100616 ctl->irq != irq)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700617 return -EINVAL;
Daniel Vettere090c532013-11-03 20:27:05 +0100618 mutex_lock(&dev->struct_mutex);
Daniel Vetterbb0f1b52013-11-03 21:09:27 +0100619 ret = drm_irq_install(dev, irq);
Daniel Vettere090c532013-11-03 20:27:05 +0100620 mutex_unlock(&dev->struct_mutex);
621
622 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700623 case DRM_UNINST_HANDLER:
Daniel Vettere090c532013-11-03 20:27:05 +0100624 mutex_lock(&dev->struct_mutex);
625 ret = drm_irq_uninstall(dev);
626 mutex_unlock(&dev->struct_mutex);
627
628 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700629 default:
630 return -EINVAL;
631 }
632}
633
634/**
Daniel Vetterf5752b32014-05-08 16:41:51 +0200635 * drm_calc_timestamping_constants - calculate vblank timestamp constants
636 * @crtc: drm_crtc whose timestamp constants should be updated.
637 * @mode: display mode containing the scanout timings
Mario Kleiner27641c32010-10-23 04:20:23 +0200638 *
Ville Syrjälä21b21562013-10-26 17:22:52 +0300639 * Calculate and store various constants which are later
640 * needed by vblank and swap-completion timestamping, e.g,
641 * by drm_calc_vbltimestamp_from_scanoutpos(). They are
Daniel Vetterf5752b32014-05-08 16:41:51 +0200642 * derived from CRTC's true scanout timing, so they take
Ville Syrjälä21b21562013-10-26 17:22:52 +0300643 * things like panel scaling or other adjustments into account.
Mario Kleiner27641c32010-10-23 04:20:23 +0200644 */
Ville Syrjälä545cdd52013-10-26 17:16:30 +0300645void drm_calc_timestamping_constants(struct drm_crtc *crtc,
646 const struct drm_display_mode *mode)
Mario Kleiner27641c32010-10-23 04:20:23 +0200647{
Ville Syrjälä0c545ac2015-11-12 14:34:18 +0200648 struct drm_device *dev = crtc->dev;
649 unsigned int pipe = drm_crtc_index(crtc);
650 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
Ville Syrjälä20b20202015-09-14 22:43:45 +0300651 int linedur_ns = 0, framedur_ns = 0;
Ville Syrjälä77666b72013-10-27 21:22:58 +0200652 int dotclock = mode->crtc_clock;
Mario Kleiner27641c32010-10-23 04:20:23 +0200653
Ville Syrjälä0c545ac2015-11-12 14:34:18 +0200654 if (!dev->num_crtcs)
655 return;
656
657 if (WARN_ON(pipe >= dev->num_crtcs))
658 return;
659
Mario Kleiner27641c32010-10-23 04:20:23 +0200660 /* Valid dotclock? */
661 if (dotclock > 0) {
Ville Syrjälä0dae35a2013-10-26 17:11:01 +0300662 int frame_size = mode->crtc_htotal * mode->crtc_vtotal;
663
664 /*
665 * Convert scanline length in pixels and video
Ville Syrjälä20b20202015-09-14 22:43:45 +0300666 * dot clock to line duration and frame duration
667 * in nanoseconds:
Mario Kleiner27641c32010-10-23 04:20:23 +0200668 */
Ville Syrjälä0dae35a2013-10-26 17:11:01 +0300669 linedur_ns = div_u64((u64) mode->crtc_htotal * 1000000, dotclock);
670 framedur_ns = div_u64((u64) frame_size * 1000000, dotclock);
Ville Syrjäläc0ae24c2013-10-28 19:53:25 +0200671
672 /*
673 * Fields of interlaced scanout modes are only half a frame duration.
674 */
675 if (mode->flags & DRM_MODE_FLAG_INTERLACE)
676 framedur_ns /= 2;
Mario Kleiner27641c32010-10-23 04:20:23 +0200677 } else
Thierry Redingcc1ef112015-08-12 17:00:31 +0200678 DRM_ERROR("crtc %u: Can't calculate constants, dotclock = 0!\n",
Mario Kleiner27641c32010-10-23 04:20:23 +0200679 crtc->base.id);
680
Ville Syrjäläeba1f352015-09-14 22:43:43 +0300681 vblank->linedur_ns = linedur_ns;
682 vblank->framedur_ns = framedur_ns;
Mario Kleiner27641c32010-10-23 04:20:23 +0200683
Thierry Redingcc1ef112015-08-12 17:00:31 +0200684 DRM_DEBUG("crtc %u: hwmode: htotal %d, vtotal %d, vdisplay %d\n",
Ville Syrjälä545cdd52013-10-26 17:16:30 +0300685 crtc->base.id, mode->crtc_htotal,
686 mode->crtc_vtotal, mode->crtc_vdisplay);
Ville Syrjälä20b20202015-09-14 22:43:45 +0300687 DRM_DEBUG("crtc %u: clock %d kHz framedur %d linedur %d\n",
688 crtc->base.id, dotclock, framedur_ns, linedur_ns);
Mario Kleiner27641c32010-10-23 04:20:23 +0200689}
690EXPORT_SYMBOL(drm_calc_timestamping_constants);
691
692/**
Daniel Vetterf5752b32014-05-08 16:41:51 +0200693 * drm_calc_vbltimestamp_from_scanoutpos - precise vblank timestamp helper
694 * @dev: DRM device
Thierry Redingcc1ef112015-08-12 17:00:31 +0200695 * @pipe: index of CRTC whose vblank timestamp to retrieve
Daniel Vetterf5752b32014-05-08 16:41:51 +0200696 * @max_error: Desired maximum allowable error in timestamps (nanosecs)
697 * On return contains true maximum error of timestamp
698 * @vblank_time: Pointer to struct timeval which should receive the timestamp
699 * @flags: Flags to pass to driver:
700 * 0 = Default,
701 * DRM_CALLED_FROM_VBLIRQ = If function is called from vbl IRQ handler
Daniel Vetterf5752b32014-05-08 16:41:51 +0200702 * @mode: mode which defines the scanout timings
703 *
704 * Implements calculation of exact vblank timestamps from given drm_display_mode
705 * timings and current video scanout position of a CRTC. This can be called from
706 * within get_vblank_timestamp() implementation of a kms driver to implement the
707 * actual timestamping.
Mario Kleiner27641c32010-10-23 04:20:23 +0200708 *
709 * Should return timestamps conforming to the OML_sync_control OpenML
710 * extension specification. The timestamp corresponds to the end of
711 * the vblank interval, aka start of scanout of topmost-leftmost display
712 * pixel in the following video frame.
713 *
714 * Requires support for optional dev->driver->get_scanout_position()
715 * in kms driver, plus a bit of setup code to provide a drm_display_mode
716 * that corresponds to the true scanout timing.
717 *
718 * The current implementation only handles standard video modes. It
719 * returns as no operation if a doublescan or interlaced video mode is
720 * active. Higher level code is expected to handle this.
721 *
Daniel Vetterf5752b32014-05-08 16:41:51 +0200722 * Returns:
723 * Negative value on error, failure or if not supported in current
Mario Kleiner27641c32010-10-23 04:20:23 +0200724 * video mode:
725 *
Daniel Vetter62cacc72016-08-12 22:48:37 +0200726 * -EINVAL Invalid CRTC.
727 * -EAGAIN Temporary unavailable, e.g., called before initial modeset.
728 * -ENOTSUPP Function not supported in current display mode.
729 * -EIO Failed, e.g., due to failed scanout position query.
Mario Kleiner27641c32010-10-23 04:20:23 +0200730 *
731 * Returns or'ed positive status flags on success:
732 *
733 * DRM_VBLANKTIME_SCANOUTPOS_METHOD - Signal this method used for timestamping.
734 * DRM_VBLANKTIME_INVBL - Timestamp taken while scanout was in vblank interval.
735 *
736 */
Thierry Redingcc1ef112015-08-12 17:00:31 +0200737int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
738 unsigned int pipe,
Mario Kleiner27641c32010-10-23 04:20:23 +0200739 int *max_error,
740 struct timeval *vblank_time,
741 unsigned flags,
Ville Syrjälä7da903e2013-10-26 17:57:31 +0300742 const struct drm_display_mode *mode)
Mario Kleiner27641c32010-10-23 04:20:23 +0200743{
Imre Deake62f2f52012-10-23 18:53:25 +0000744 struct timeval tv_etime;
Thomas Gleixnerd2cb58c2014-07-16 21:04:26 +0000745 ktime_t stime, etime;
Ville Syrjäläad1716e2015-09-14 22:43:49 +0300746 unsigned int vbl_status;
747 int ret = DRM_VBLANKTIME_SCANOUTPOS_METHOD;
Mario Kleiner27641c32010-10-23 04:20:23 +0200748 int vpos, hpos, i;
Ville Syrjälä3bb403b2015-09-14 22:43:44 +0300749 int delta_ns, duration_ns;
Mario Kleiner27641c32010-10-23 04:20:23 +0200750
Thierry Redingcc1ef112015-08-12 17:00:31 +0200751 if (pipe >= dev->num_crtcs) {
752 DRM_ERROR("Invalid crtc %u\n", pipe);
Mario Kleiner27641c32010-10-23 04:20:23 +0200753 return -EINVAL;
754 }
755
756 /* Scanout position query not supported? Should not happen. */
757 if (!dev->driver->get_scanout_position) {
758 DRM_ERROR("Called from driver w/o get_scanout_position()!?\n");
759 return -EIO;
760 }
761
Mario Kleiner27641c32010-10-23 04:20:23 +0200762 /* If mode timing undefined, just return as no-op:
763 * Happens during initial modesetting of a crtc.
764 */
Ville Syrjälä3bb403b2015-09-14 22:43:44 +0300765 if (mode->crtc_clock == 0) {
Thierry Redingcc1ef112015-08-12 17:00:31 +0200766 DRM_DEBUG("crtc %u: Noop due to uninitialized mode.\n", pipe);
Mario Kleiner27641c32010-10-23 04:20:23 +0200767 return -EAGAIN;
768 }
769
Mario Kleiner27641c32010-10-23 04:20:23 +0200770 /* Get current scanout position with system timestamp.
771 * Repeat query up to DRM_TIMESTAMP_MAXRETRIES times
772 * if single query takes longer than max_error nanoseconds.
773 *
774 * This guarantees a tight bound on maximum error if
775 * code gets preempted or delayed for some reason.
776 */
777 for (i = 0; i < DRM_TIMESTAMP_MAXRETRIES; i++) {
Mario Kleiner8f6fce02013-10-30 05:13:06 +0100778 /*
779 * Get vertical and horizontal scanout position vpos, hpos,
780 * and bounding timestamps stime, etime, pre/post query.
781 */
Ville Syrjälä3bb403b2015-09-14 22:43:44 +0300782 vbl_status = dev->driver->get_scanout_position(dev, pipe, flags,
783 &vpos, &hpos,
784 &stime, &etime,
785 mode);
Mario Kleiner27641c32010-10-23 04:20:23 +0200786
Mario Kleiner27641c32010-10-23 04:20:23 +0200787 /* Return as no-op if scanout query unsupported or failed. */
788 if (!(vbl_status & DRM_SCANOUTPOS_VALID)) {
Ville Syrjäläad1716e2015-09-14 22:43:49 +0300789 DRM_DEBUG("crtc %u : scanoutpos query failed [0x%x].\n",
Thierry Redingcc1ef112015-08-12 17:00:31 +0200790 pipe, vbl_status);
Mario Kleiner27641c32010-10-23 04:20:23 +0200791 return -EIO;
792 }
793
Mario Kleiner8f6fce02013-10-30 05:13:06 +0100794 /* Compute uncertainty in timestamp of scanout position query. */
Imre Deake62f2f52012-10-23 18:53:25 +0000795 duration_ns = ktime_to_ns(etime) - ktime_to_ns(stime);
Mario Kleiner27641c32010-10-23 04:20:23 +0200796
797 /* Accept result with < max_error nsecs timing uncertainty. */
Ville Syrjälä3c184f62013-10-26 17:38:52 +0300798 if (duration_ns <= *max_error)
Mario Kleiner27641c32010-10-23 04:20:23 +0200799 break;
800 }
801
802 /* Noisy system timing? */
803 if (i == DRM_TIMESTAMP_MAXRETRIES) {
Thierry Redingcc1ef112015-08-12 17:00:31 +0200804 DRM_DEBUG("crtc %u: Noisy timestamp %d us > %d us [%d reps].\n",
805 pipe, duration_ns/1000, *max_error/1000, i);
Mario Kleiner27641c32010-10-23 04:20:23 +0200806 }
807
808 /* Return upper bound of timestamp precision error. */
Ville Syrjälä3c184f62013-10-26 17:38:52 +0300809 *max_error = duration_ns;
Mario Kleiner27641c32010-10-23 04:20:23 +0200810
811 /* Check if in vblank area:
812 * vpos is >=0 in video scanout area, but negative
813 * within vblank area, counting down the number of lines until
814 * start of scanout.
815 */
Ville Syrjäläad1716e2015-09-14 22:43:49 +0300816 if (vbl_status & DRM_SCANOUTPOS_IN_VBLANK)
817 ret |= DRM_VBLANKTIME_IN_VBLANK;
Mario Kleiner27641c32010-10-23 04:20:23 +0200818
819 /* Convert scanout position into elapsed time at raw_time query
820 * since start of scanout at first display scanline. delta_ns
821 * can be negative if start of scanout hasn't happened yet.
822 */
Ville Syrjälä3bb403b2015-09-14 22:43:44 +0300823 delta_ns = div_s64(1000000LL * (vpos * mode->crtc_htotal + hpos),
824 mode->crtc_clock);
Mario Kleiner27641c32010-10-23 04:20:23 +0200825
Imre Deakc61eef72012-10-23 18:53:26 +0000826 if (!drm_timestamp_monotonic)
Thomas Gleixnerd2cb58c2014-07-16 21:04:26 +0000827 etime = ktime_mono_to_real(etime);
Imre Deakc61eef72012-10-23 18:53:26 +0000828
Imre Deake62f2f52012-10-23 18:53:25 +0000829 /* save this only for debugging purposes */
830 tv_etime = ktime_to_timeval(etime);
Mario Kleiner27641c32010-10-23 04:20:23 +0200831 /* Subtract time delta from raw timestamp to get final
832 * vblank_time timestamp for end of vblank.
833 */
Daniel Vettera91d7b92016-03-29 13:12:22 +0200834 etime = ktime_sub_ns(etime, delta_ns);
Imre Deake62f2f52012-10-23 18:53:25 +0000835 *vblank_time = ktime_to_timeval(etime);
Mario Kleiner27641c32010-10-23 04:20:23 +0200836
Ville Syrjälä235fabe2015-10-09 22:57:37 +0300837 DRM_DEBUG_VBL("crtc %u : v 0x%x p(%d,%d)@ %ld.%ld -> %ld.%ld [e %d us, %d rep]\n",
838 pipe, vbl_status, hpos, vpos,
839 (long)tv_etime.tv_sec, (long)tv_etime.tv_usec,
840 (long)vblank_time->tv_sec, (long)vblank_time->tv_usec,
841 duration_ns/1000, i);
Mario Kleiner27641c32010-10-23 04:20:23 +0200842
Ville Syrjäläad1716e2015-09-14 22:43:49 +0300843 return ret;
Mario Kleiner27641c32010-10-23 04:20:23 +0200844}
845EXPORT_SYMBOL(drm_calc_vbltimestamp_from_scanoutpos);
846
Imre Deakc61eef72012-10-23 18:53:26 +0000847static struct timeval get_drm_timestamp(void)
848{
849 ktime_t now;
850
Thomas Gleixnerd2cb58c2014-07-16 21:04:26 +0000851 now = drm_timestamp_monotonic ? ktime_get() : ktime_get_real();
Imre Deakc61eef72012-10-23 18:53:26 +0000852 return ktime_to_timeval(now);
853}
854
Mario Kleiner27641c32010-10-23 04:20:23 +0200855/**
856 * drm_get_last_vbltimestamp - retrieve raw timestamp for the most recent
Thierry Reding4dfd9092014-12-10 13:03:34 +0100857 * vblank interval
Mario Kleiner27641c32010-10-23 04:20:23 +0200858 * @dev: DRM device
Thierry Redingcc1ef112015-08-12 17:00:31 +0200859 * @pipe: index of CRTC whose vblank timestamp to retrieve
Mario Kleiner27641c32010-10-23 04:20:23 +0200860 * @tvblank: Pointer to target struct timeval which should receive the timestamp
861 * @flags: Flags to pass to driver:
Daniel Vetterf5752b32014-05-08 16:41:51 +0200862 * 0 = Default,
863 * DRM_CALLED_FROM_VBLIRQ = If function is called from vbl IRQ handler
Mario Kleiner27641c32010-10-23 04:20:23 +0200864 *
865 * Fetches the system timestamp corresponding to the time of the most recent
Daniel Vetterf5752b32014-05-08 16:41:51 +0200866 * vblank interval on specified CRTC. May call into kms-driver to
Mario Kleiner27641c32010-10-23 04:20:23 +0200867 * compute the timestamp with a high-precision GPU specific method.
868 *
869 * Returns zero if timestamp originates from uncorrected do_gettimeofday()
870 * call, i.e., it isn't very precisely locked to the true vblank.
871 *
Daniel Vetterf5752b32014-05-08 16:41:51 +0200872 * Returns:
Daniel Vetterfb446a12014-09-10 17:36:10 +0200873 * True if timestamp is considered to be very precise, false otherwise.
Mario Kleiner27641c32010-10-23 04:20:23 +0200874 */
Daniel Vetterfb446a12014-09-10 17:36:10 +0200875static bool
Thierry Redingcc1ef112015-08-12 17:00:31 +0200876drm_get_last_vbltimestamp(struct drm_device *dev, unsigned int pipe,
Daniel Vetterfb446a12014-09-10 17:36:10 +0200877 struct timeval *tvblank, unsigned flags)
Mario Kleiner27641c32010-10-23 04:20:23 +0200878{
Laurent Pinchart4a1b0712012-05-17 13:27:21 +0200879 int ret;
Mario Kleiner27641c32010-10-23 04:20:23 +0200880
881 /* Define requested maximum error on timestamps (nanoseconds). */
882 int max_error = (int) drm_timestamp_precision * 1000;
883
884 /* Query driver if possible and precision timestamping enabled. */
885 if (dev->driver->get_vblank_timestamp && (max_error > 0)) {
Thierry Redingcc1ef112015-08-12 17:00:31 +0200886 ret = dev->driver->get_vblank_timestamp(dev, pipe, &max_error,
Mario Kleiner27641c32010-10-23 04:20:23 +0200887 tvblank, flags);
888 if (ret > 0)
Daniel Vetterfb446a12014-09-10 17:36:10 +0200889 return true;
Mario Kleiner27641c32010-10-23 04:20:23 +0200890 }
891
892 /* GPU high precision timestamp query unsupported or failed.
Imre Deakc61eef72012-10-23 18:53:26 +0000893 * Return current monotonic/gettimeofday timestamp as best estimate.
Mario Kleiner27641c32010-10-23 04:20:23 +0200894 */
Imre Deakc61eef72012-10-23 18:53:26 +0000895 *tvblank = get_drm_timestamp();
Mario Kleiner27641c32010-10-23 04:20:23 +0200896
Daniel Vetterfb446a12014-09-10 17:36:10 +0200897 return false;
Mario Kleiner27641c32010-10-23 04:20:23 +0200898}
Mario Kleiner27641c32010-10-23 04:20:23 +0200899
900/**
Thierry Reding96d3f912014-12-16 13:08:47 +0100901 * drm_crtc_vblank_count - retrieve "cooked" vblank counter value
902 * @crtc: which counter to retrieve
903 *
904 * Fetches the "cooked" vblank count value that represents the number of
905 * vblank events since the system was booted, including lost events due to
906 * modesetting activity.
907 *
Thierry Reding96d3f912014-12-16 13:08:47 +0100908 * Returns:
909 * The software vblank counter.
910 */
911u32 drm_crtc_vblank_count(struct drm_crtc *crtc)
912{
913 return drm_vblank_count(crtc->dev, drm_crtc_index(crtc));
914}
915EXPORT_SYMBOL(drm_crtc_vblank_count);
916
917/**
Thierry Redingcc1ef112015-08-12 17:00:31 +0200918 * drm_vblank_count_and_time - retrieve "cooked" vblank counter value and the
919 * system timestamp corresponding to that vblank counter value.
Mario Kleiner27641c32010-10-23 04:20:23 +0200920 * @dev: DRM device
Thierry Redingcc1ef112015-08-12 17:00:31 +0200921 * @pipe: index of CRTC whose counter to retrieve
Mario Kleiner27641c32010-10-23 04:20:23 +0200922 * @vblanktime: Pointer to struct timeval to receive the vblank timestamp.
923 *
924 * Fetches the "cooked" vblank count value that represents the number of
925 * vblank events since the system was booted, including lost events due to
926 * modesetting activity. Returns corresponding system timestamp of the time
Daniel Vetterf5752b32014-05-08 16:41:51 +0200927 * of the vblank interval that corresponds to the current vblank counter value.
Thierry Redingcf648302015-09-24 18:35:36 +0200928 *
929 * This is the legacy version of drm_crtc_vblank_count_and_time().
Mario Kleiner27641c32010-10-23 04:20:23 +0200930 */
Gustavo Padovan6e5f73f2016-07-04 21:04:47 -0300931static u32 drm_vblank_count_and_time(struct drm_device *dev, unsigned int pipe,
932 struct timeval *vblanktime)
Mario Kleiner27641c32010-10-23 04:20:23 +0200933{
Thierry Redingcc1ef112015-08-12 17:00:31 +0200934 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
Matthew Auldd4055a92016-05-10 15:21:28 +0100935 u32 vblank_count;
936 unsigned int seq;
Mario Kleiner27641c32010-10-23 04:20:23 +0200937
Arnd Bergmanncff52e52016-10-18 00:13:39 +0200938 if (WARN_ON(pipe >= dev->num_crtcs)) {
939 *vblanktime = (struct timeval) { 0 };
Rob Clarke6ae8682014-08-06 13:16:59 -0400940 return 0;
Arnd Bergmanncff52e52016-10-18 00:13:39 +0200941 }
Rob Clarke6ae8682014-08-06 13:16:59 -0400942
Mario Kleiner27641c32010-10-23 04:20:23 +0200943 do {
Matthew Auldd4055a92016-05-10 15:21:28 +0100944 seq = read_seqbegin(&vblank->seqlock);
945 vblank_count = vblank->count;
946 *vblanktime = vblank->time;
947 } while (read_seqretry(&vblank->seqlock, seq));
Mario Kleiner27641c32010-10-23 04:20:23 +0200948
Matthew Auldd4055a92016-05-10 15:21:28 +0100949 return vblank_count;
Mario Kleiner27641c32010-10-23 04:20:23 +0200950}
Mario Kleiner27641c32010-10-23 04:20:23 +0200951
Thierry Redingcf648302015-09-24 18:35:36 +0200952/**
953 * drm_crtc_vblank_count_and_time - retrieve "cooked" vblank counter value
954 * and the system timestamp corresponding to that vblank counter value
955 * @crtc: which counter to retrieve
956 * @vblanktime: Pointer to struct timeval to receive the vblank timestamp.
957 *
958 * Fetches the "cooked" vblank count value that represents the number of
959 * vblank events since the system was booted, including lost events due to
960 * modesetting activity. Returns corresponding system timestamp of the time
961 * of the vblank interval that corresponds to the current vblank counter value.
Thierry Redingcf648302015-09-24 18:35:36 +0200962 */
963u32 drm_crtc_vblank_count_and_time(struct drm_crtc *crtc,
964 struct timeval *vblanktime)
965{
966 return drm_vblank_count_and_time(crtc->dev, drm_crtc_index(crtc),
967 vblanktime);
968}
969EXPORT_SYMBOL(drm_crtc_vblank_count_and_time);
970
Rob Clarkc6eefa12012-10-16 22:48:40 +0000971static void send_vblank_event(struct drm_device *dev,
972 struct drm_pending_vblank_event *e,
973 unsigned long seq, struct timeval *now)
974{
Rob Clarkc6eefa12012-10-16 22:48:40 +0000975 e->event.sequence = seq;
976 e->event.tv_sec = now->tv_sec;
977 e->event.tv_usec = now->tv_usec;
978
Rob Clarkc6eefa12012-10-16 22:48:40 +0000979 trace_drm_vblank_event_delivered(e->base.pid, e->pipe,
980 e->event.sequence);
Matthew Auldc001da42016-06-20 17:42:46 +0100981
982 drm_send_event_locked(dev, &e->base);
Rob Clarkc6eefa12012-10-16 22:48:40 +0000983}
984
985/**
Daniel Vetterbbc87642015-11-10 17:37:31 +0100986 * drm_crtc_arm_vblank_event - arm vblank event after pageflip
987 * @crtc: the source CRTC of the vblank event
988 * @e: the event to send
989 *
990 * A lot of drivers need to generate vblank events for the very next vblank
991 * interrupt. For example when the page flip interrupt happens when the page
992 * flip gets armed, but not when it actually executes within the next vblank
993 * period. This helper function implements exactly the required vblank arming
994 * behaviour.
995 *
Daniel Vetter61802132016-09-30 12:04:56 +0200996 * NOTE: Drivers using this to send out the event in struct &drm_crtc_state
997 * as part of an atomic commit must ensure that the next vblank happens at
998 * exactly the same time as the atomic commit is committed to the hardware. This
999 * function itself does **not** protect again the next vblank interrupt racing
1000 * with either this function call or the atomic commit operation. A possible
1001 * sequence could be:
1002 *
1003 * 1. Driver commits new hardware state into vblank-synchronized registers.
1004 * 2. A vblank happens, committing the hardware state. Also the corresponding
1005 * vblank interrupt is fired off and fully processed by the interrupt
1006 * handler.
1007 * 3. The atomic commit operation proceeds to call drm_crtc_arm_vblank_event().
1008 * 4. The event is only send out for the next vblank, which is wrong.
1009 *
1010 * An equivalent race can happen when the driver calls
1011 * drm_crtc_arm_vblank_event() before writing out the new hardware state.
1012 *
1013 * The only way to make this work safely is to prevent the vblank from firing
1014 * (and the hardware from committing anything else) until the entire atomic
1015 * commit sequence has run to completion. If the hardware does not have such a
1016 * feature (e.g. using a "go" bit), then it is unsafe to use this functions.
1017 * Instead drivers need to manually send out the event from their interrupt
1018 * handler by calling drm_crtc_send_vblank_event() and make sure that there's no
1019 * possible race with the hardware committing the atomic update.
1020 *
Daniel Vetterbbc87642015-11-10 17:37:31 +01001021 * Caller must hold event lock. Caller must also hold a vblank reference for
1022 * the event @e, which will be dropped when the next vblank arrives.
Daniel Vetterbbc87642015-11-10 17:37:31 +01001023 */
1024void drm_crtc_arm_vblank_event(struct drm_crtc *crtc,
1025 struct drm_pending_vblank_event *e)
1026{
Gustavo Padovan93507d12016-06-07 11:07:55 -03001027 struct drm_device *dev = crtc->dev;
1028 unsigned int pipe = drm_crtc_index(crtc);
1029
1030 assert_spin_locked(&dev->event_lock);
1031
1032 e->pipe = pipe;
1033 e->event.sequence = drm_vblank_count(dev, pipe);
1034 list_add_tail(&e->base.link, &dev->vblank_event_list);
Daniel Vetterbbc87642015-11-10 17:37:31 +01001035}
1036EXPORT_SYMBOL(drm_crtc_arm_vblank_event);
1037
1038/**
Gustavo Padovandb749b72016-06-07 11:07:54 -03001039 * drm_crtc_send_vblank_event - helper to send vblank event after pageflip
1040 * @crtc: the source CRTC of the vblank event
Rob Clarkc6eefa12012-10-16 22:48:40 +00001041 * @e: the event to send
1042 *
Daniel Vetter61802132016-09-30 12:04:56 +02001043 * Updates sequence # and timestamp on event for the most recently processed
1044 * vblank, and sends it to userspace. Caller must hold event lock.
1045 *
1046 * See drm_crtc_arm_vblank_event() for a helper which can be used in certain
1047 * situation, especially to send out events for atomic commit operations.
Rob Clarkc6eefa12012-10-16 22:48:40 +00001048 */
Gustavo Padovandb749b72016-06-07 11:07:54 -03001049void drm_crtc_send_vblank_event(struct drm_crtc *crtc,
1050 struct drm_pending_vblank_event *e)
Rob Clarkc6eefa12012-10-16 22:48:40 +00001051{
Gustavo Padovandb749b72016-06-07 11:07:54 -03001052 struct drm_device *dev = crtc->dev;
1053 unsigned int seq, pipe = drm_crtc_index(crtc);
Rob Clarkc6eefa12012-10-16 22:48:40 +00001054 struct timeval now;
Thierry Reding4dfd9092014-12-10 13:03:34 +01001055
Thierry Reding2a7d3d62015-08-12 17:00:24 +02001056 if (dev->num_crtcs > 0) {
Thierry Redingcc1ef112015-08-12 17:00:31 +02001057 seq = drm_vblank_count_and_time(dev, pipe, &now);
Rob Clarkc6eefa12012-10-16 22:48:40 +00001058 } else {
1059 seq = 0;
Imre Deakc61eef72012-10-23 18:53:26 +00001060
1061 now = get_drm_timestamp();
Rob Clarkc6eefa12012-10-16 22:48:40 +00001062 }
Thierry Redingcc1ef112015-08-12 17:00:31 +02001063 e->pipe = pipe;
Rob Clarkc6eefa12012-10-16 22:48:40 +00001064 send_vblank_event(dev, e, seq, &now);
1065}
Thierry Redinga4d7b302014-12-15 14:47:18 +01001066EXPORT_SYMBOL(drm_crtc_send_vblank_event);
1067
1068/**
Ville Syrjäläf2752282014-02-19 21:29:49 +02001069 * drm_vblank_enable - enable the vblank interrupt on a CRTC
1070 * @dev: DRM device
Thierry Redingcc1ef112015-08-12 17:00:31 +02001071 * @pipe: CRTC index
Thierry Redingc30e11f2015-08-12 17:00:33 +02001072 *
1073 * Returns:
1074 * Zero on success or a negative error code on failure.
Ville Syrjäläf2752282014-02-19 21:29:49 +02001075 */
Thierry Redingcc1ef112015-08-12 17:00:31 +02001076static int drm_vblank_enable(struct drm_device *dev, unsigned int pipe)
Ville Syrjäläf2752282014-02-19 21:29:49 +02001077{
Thierry Redingcc1ef112015-08-12 17:00:31 +02001078 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
Ville Syrjäläf2752282014-02-19 21:29:49 +02001079 int ret = 0;
1080
1081 assert_spin_locked(&dev->vbl_lock);
1082
1083 spin_lock(&dev->vblank_time_lock);
1084
Ville Syrjälä8a51d5b2014-08-06 14:49:50 +03001085 if (!vblank->enabled) {
Daniel Vetter1cfb80b2014-05-21 15:11:33 +02001086 /*
1087 * Enable vblank irqs under vblank_time_lock protection.
Ville Syrjäläf2752282014-02-19 21:29:49 +02001088 * All vblank count & timestamp updates are held off
1089 * until we are done reinitializing master counter and
1090 * timestamps. Filtercode in drm_handle_vblank() will
1091 * prevent double-accounting of same vblank interval.
1092 */
Thierry Redingcc1ef112015-08-12 17:00:31 +02001093 ret = dev->driver->enable_vblank(dev, pipe);
1094 DRM_DEBUG("enabling vblank on crtc %u, ret: %d\n", pipe, ret);
Ville Syrjäläf2752282014-02-19 21:29:49 +02001095 if (ret)
Ville Syrjälä8a51d5b2014-08-06 14:49:50 +03001096 atomic_dec(&vblank->refcount);
Ville Syrjäläf2752282014-02-19 21:29:49 +02001097 else {
Ville Syrjälä8a51d5b2014-08-06 14:49:50 +03001098 vblank->enabled = true;
Ville Syrjäläa6e610d2015-09-14 22:43:47 +03001099 drm_update_vblank_count(dev, pipe, 0);
Ville Syrjäläf2752282014-02-19 21:29:49 +02001100 }
1101 }
1102
1103 spin_unlock(&dev->vblank_time_lock);
1104
1105 return ret;
1106}
1107
1108/**
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001109 * drm_vblank_get - get a reference count on vblank events
1110 * @dev: DRM device
Thierry Redingcc1ef112015-08-12 17:00:31 +02001111 * @pipe: index of CRTC to own
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001112 *
1113 * Acquire a reference count on vblank events to avoid having them disabled
1114 * while in use.
1115 *
Daniel Vetter89dd6a42014-05-15 15:32:12 +02001116 * This is the legacy version of drm_crtc_vblank_get().
1117 *
Daniel Vetterf5752b32014-05-08 16:41:51 +02001118 * Returns:
Thierry Redingc30e11f2015-08-12 17:00:33 +02001119 * Zero on success or a negative error code on failure.
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001120 */
Gustavo Padovanceb74152016-06-07 11:07:56 -03001121static int drm_vblank_get(struct drm_device *dev, unsigned int pipe)
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001122{
Thierry Redingcc1ef112015-08-12 17:00:31 +02001123 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
Peter Hurley97cbc882013-08-20 21:51:12 -04001124 unsigned long irqflags;
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001125 int ret = 0;
1126
Gerd Hoffmann16e32472015-03-30 12:50:50 +02001127 if (!dev->num_crtcs)
1128 return -EINVAL;
1129
Thierry Redingcc1ef112015-08-12 17:00:31 +02001130 if (WARN_ON(pipe >= dev->num_crtcs))
Rob Clarke6ae8682014-08-06 13:16:59 -04001131 return -EINVAL;
1132
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001133 spin_lock_irqsave(&dev->vbl_lock, irqflags);
1134 /* Going from 0->1 means we have to enable interrupts again */
Ville Syrjälä8a51d5b2014-08-06 14:49:50 +03001135 if (atomic_add_return(1, &vblank->refcount) == 1) {
Thierry Redingcc1ef112015-08-12 17:00:31 +02001136 ret = drm_vblank_enable(dev, pipe);
Li Peng778c9022009-11-09 12:51:22 +08001137 } else {
Ville Syrjälä8a51d5b2014-08-06 14:49:50 +03001138 if (!vblank->enabled) {
1139 atomic_dec(&vblank->refcount);
Li Peng778c9022009-11-09 12:51:22 +08001140 ret = -EINVAL;
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001141 }
1142 }
1143 spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
1144
1145 return ret;
1146}
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001147
1148/**
Daniel Vetter89dd6a42014-05-15 15:32:12 +02001149 * drm_crtc_vblank_get - get a reference count on vblank events
1150 * @crtc: which CRTC to own
1151 *
1152 * Acquire a reference count on vblank events to avoid having them disabled
1153 * while in use.
1154 *
Daniel Vetter89dd6a42014-05-15 15:32:12 +02001155 * Returns:
Thierry Redingc30e11f2015-08-12 17:00:33 +02001156 * Zero on success or a negative error code on failure.
Daniel Vetter89dd6a42014-05-15 15:32:12 +02001157 */
1158int drm_crtc_vblank_get(struct drm_crtc *crtc)
1159{
1160 return drm_vblank_get(crtc->dev, drm_crtc_index(crtc));
1161}
1162EXPORT_SYMBOL(drm_crtc_vblank_get);
1163
1164/**
Thierry Redingcc1ef112015-08-12 17:00:31 +02001165 * drm_vblank_put - release ownership of vblank events
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001166 * @dev: DRM device
Thierry Redingcc1ef112015-08-12 17:00:31 +02001167 * @pipe: index of CRTC to release
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001168 *
1169 * Release ownership of a given vblank counter, turning off interrupts
Mario Kleiner27641c32010-10-23 04:20:23 +02001170 * if possible. Disable interrupts after drm_vblank_offdelay milliseconds.
Daniel Vetter89dd6a42014-05-15 15:32:12 +02001171 *
1172 * This is the legacy version of drm_crtc_vblank_put().
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001173 */
Gustavo Padovanceb74152016-06-07 11:07:56 -03001174static void drm_vblank_put(struct drm_device *dev, unsigned int pipe)
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001175{
Thierry Redingcc1ef112015-08-12 17:00:31 +02001176 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
Ville Syrjälä8a51d5b2014-08-06 14:49:50 +03001177
Thierry Redingcc1ef112015-08-12 17:00:31 +02001178 if (WARN_ON(pipe >= dev->num_crtcs))
Rob Clark7f907bf22014-11-08 10:16:19 -05001179 return;
Chris Wilsonb3f5e732009-02-19 14:48:22 +00001180
Thierry Reding7d1de852015-08-12 17:00:30 +02001181 if (WARN_ON(atomic_read(&vblank->refcount) == 0))
Rob Clarke6ae8682014-08-06 13:16:59 -04001182 return;
1183
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001184 /* Last user schedules interrupt disable */
Ville Syrjälä4ed0ce32014-08-06 14:49:53 +03001185 if (atomic_dec_and_test(&vblank->refcount)) {
Daniel Vetterab8905f12014-09-10 17:36:08 +02001186 if (drm_vblank_offdelay == 0)
1187 return;
1188 else if (dev->vblank_disable_immediate || drm_vblank_offdelay < 0)
Ville Syrjälä4ed0ce32014-08-06 14:49:53 +03001189 vblank_disable_fn((unsigned long)vblank);
Daniel Vetterab8905f12014-09-10 17:36:08 +02001190 else
Ville Syrjälä4ed0ce32014-08-06 14:49:53 +03001191 mod_timer(&vblank->disable_timer,
1192 jiffies + ((drm_vblank_offdelay * HZ)/1000));
1193 }
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001194}
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001195
Rob Clarkc6eefa12012-10-16 22:48:40 +00001196/**
Daniel Vetter89dd6a42014-05-15 15:32:12 +02001197 * drm_crtc_vblank_put - give up ownership of vblank events
1198 * @crtc: which counter to give up
1199 *
1200 * Release ownership of a given vblank counter, turning off interrupts
1201 * if possible. Disable interrupts after drm_vblank_offdelay milliseconds.
Daniel Vetter89dd6a42014-05-15 15:32:12 +02001202 */
1203void drm_crtc_vblank_put(struct drm_crtc *crtc)
1204{
1205 drm_vblank_put(crtc->dev, drm_crtc_index(crtc));
1206}
1207EXPORT_SYMBOL(drm_crtc_vblank_put);
1208
1209/**
Daniel Vettere8450f52014-07-25 23:34:03 +02001210 * drm_wait_one_vblank - wait for one vblank
1211 * @dev: DRM device
Thierry Redingcc1ef112015-08-12 17:00:31 +02001212 * @pipe: CRTC index
Daniel Vettere8450f52014-07-25 23:34:03 +02001213 *
Ville Syrjälä1da248a2015-09-14 22:43:42 +03001214 * This waits for one vblank to pass on @pipe, using the irq driver interfaces.
1215 * It is a failure to call this when the vblank irq for @pipe is disabled, e.g.
Daniel Vettere8450f52014-07-25 23:34:03 +02001216 * due to lack of driver support or because the crtc is off.
1217 */
Thierry Redingcc1ef112015-08-12 17:00:31 +02001218void drm_wait_one_vblank(struct drm_device *dev, unsigned int pipe)
Daniel Vettere8450f52014-07-25 23:34:03 +02001219{
Thierry Redingcc1ef112015-08-12 17:00:31 +02001220 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
Daniel Vettere8450f52014-07-25 23:34:03 +02001221 int ret;
1222 u32 last;
1223
Thierry Redingcc1ef112015-08-12 17:00:31 +02001224 if (WARN_ON(pipe >= dev->num_crtcs))
Thierry Reding7d1de852015-08-12 17:00:30 +02001225 return;
1226
Thierry Redingcc1ef112015-08-12 17:00:31 +02001227 ret = drm_vblank_get(dev, pipe);
1228 if (WARN(ret, "vblank not available on crtc %i, ret=%i\n", pipe, ret))
Daniel Vettere8450f52014-07-25 23:34:03 +02001229 return;
1230
Thierry Redingcc1ef112015-08-12 17:00:31 +02001231 last = drm_vblank_count(dev, pipe);
Daniel Vettere8450f52014-07-25 23:34:03 +02001232
Thierry Redingcc1ef112015-08-12 17:00:31 +02001233 ret = wait_event_timeout(vblank->queue,
1234 last != drm_vblank_count(dev, pipe),
Daniel Vettere8450f52014-07-25 23:34:03 +02001235 msecs_to_jiffies(100));
1236
Thierry Redingcc1ef112015-08-12 17:00:31 +02001237 WARN(ret == 0, "vblank wait timed out on crtc %i\n", pipe);
Daniel Vettere8450f52014-07-25 23:34:03 +02001238
Thierry Redingcc1ef112015-08-12 17:00:31 +02001239 drm_vblank_put(dev, pipe);
Daniel Vettere8450f52014-07-25 23:34:03 +02001240}
1241EXPORT_SYMBOL(drm_wait_one_vblank);
1242
1243/**
1244 * drm_crtc_wait_one_vblank - wait for one vblank
1245 * @crtc: DRM crtc
1246 *
1247 * This waits for one vblank to pass on @crtc, using the irq driver interfaces.
1248 * It is a failure to call this when the vblank irq for @crtc is disabled, e.g.
1249 * due to lack of driver support or because the crtc is off.
1250 */
1251void drm_crtc_wait_one_vblank(struct drm_crtc *crtc)
1252{
1253 drm_wait_one_vblank(crtc->dev, drm_crtc_index(crtc));
1254}
1255EXPORT_SYMBOL(drm_crtc_wait_one_vblank);
1256
1257/**
Daniel Vetter2d1e3312016-11-14 10:02:54 +01001258 * drm_crtc_vblank_off - disable vblank events on a CRTC
1259 * @crtc: CRTC in question
Rob Clarkc6eefa12012-10-16 22:48:40 +00001260 *
Daniel Vetterf5752b32014-05-08 16:41:51 +02001261 * Drivers can use this function to shut down the vblank interrupt handling when
1262 * disabling a crtc. This function ensures that the latest vblank frame count is
Daniel Vetter2d1e3312016-11-14 10:02:54 +01001263 * stored so that drm_vblank_on can restore it again.
Daniel Vetterf5752b32014-05-08 16:41:51 +02001264 *
1265 * Drivers must use this function when the hardware vblank counter can get
1266 * reset, e.g. when suspending.
Rob Clarkc6eefa12012-10-16 22:48:40 +00001267 */
Daniel Vetter2d1e3312016-11-14 10:02:54 +01001268void drm_crtc_vblank_off(struct drm_crtc *crtc)
Li Peng778c9022009-11-09 12:51:22 +08001269{
Daniel Vetter2d1e3312016-11-14 10:02:54 +01001270 struct drm_device *dev = crtc->dev;
1271 unsigned int pipe = drm_crtc_index(crtc);
Thierry Redingcc1ef112015-08-12 17:00:31 +02001272 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
Christopher James Halse Rogers498548e2011-04-27 16:10:57 +10001273 struct drm_pending_vblank_event *e, *t;
1274 struct timeval now;
Li Peng778c9022009-11-09 12:51:22 +08001275 unsigned long irqflags;
Christopher James Halse Rogers498548e2011-04-27 16:10:57 +10001276 unsigned int seq;
Li Peng778c9022009-11-09 12:51:22 +08001277
Thierry Redingcc1ef112015-08-12 17:00:31 +02001278 if (WARN_ON(pipe >= dev->num_crtcs))
Rob Clarke6ae8682014-08-06 13:16:59 -04001279 return;
1280
Ville Syrjälä56cc2792014-08-06 14:49:51 +03001281 spin_lock_irqsave(&dev->event_lock, irqflags);
1282
1283 spin_lock(&dev->vbl_lock);
Mario Kleinere8235892016-02-12 20:30:27 +01001284 DRM_DEBUG_VBL("crtc %d, vblank enabled %d, inmodeset %d\n",
1285 pipe, vblank->enabled, vblank->inmodeset);
1286
Daniel Vetter2d1e3312016-11-14 10:02:54 +01001287 /* Avoid redundant vblank disables without previous
1288 * drm_crtc_vblank_on(). */
Mario Kleinere8235892016-02-12 20:30:27 +01001289 if (drm_core_check_feature(dev, DRIVER_ATOMIC) || !vblank->inmodeset)
1290 vblank_disable_and_save(dev, pipe);
1291
Ville Syrjälä8a51d5b2014-08-06 14:49:50 +03001292 wake_up(&vblank->queue);
Christopher James Halse Rogers498548e2011-04-27 16:10:57 +10001293
Ville Syrjälä56cc2792014-08-06 14:49:51 +03001294 /*
1295 * Prevent subsequent drm_vblank_get() from re-enabling
1296 * the vblank interrupt by bumping the refcount.
1297 */
1298 if (!vblank->inmodeset) {
1299 atomic_inc(&vblank->refcount);
1300 vblank->inmodeset = 1;
1301 }
1302 spin_unlock(&dev->vbl_lock);
1303
Christopher James Halse Rogers498548e2011-04-27 16:10:57 +10001304 /* Send any queued vblank events, lest the natives grow disquiet */
Thierry Redingcc1ef112015-08-12 17:00:31 +02001305 seq = drm_vblank_count_and_time(dev, pipe, &now);
Imre Deake7783ba2012-11-02 13:30:50 +02001306
Christopher James Halse Rogers498548e2011-04-27 16:10:57 +10001307 list_for_each_entry_safe(e, t, &dev->vblank_event_list, base.link) {
Thierry Redingcc1ef112015-08-12 17:00:31 +02001308 if (e->pipe != pipe)
Christopher James Halse Rogers498548e2011-04-27 16:10:57 +10001309 continue;
Ville Syrjälä44844892015-10-09 22:57:36 +03001310 DRM_DEBUG("Sending premature vblank event on disable: "
Rodrigo Vivi1d776852016-08-03 09:53:46 -07001311 "wanted %u, current %u\n",
Christopher James Halse Rogers498548e2011-04-27 16:10:57 +10001312 e->event.sequence, seq);
Rob Clarkc6eefa12012-10-16 22:48:40 +00001313 list_del(&e->base.link);
Thierry Redingcc1ef112015-08-12 17:00:31 +02001314 drm_vblank_put(dev, pipe);
Rob Clarkc6eefa12012-10-16 22:48:40 +00001315 send_vblank_event(dev, e, seq, &now);
Christopher James Halse Rogers498548e2011-04-27 16:10:57 +10001316 }
Ville Syrjälä56cc2792014-08-06 14:49:51 +03001317 spin_unlock_irqrestore(&dev->event_lock, irqflags);
Li Peng778c9022009-11-09 12:51:22 +08001318}
Daniel Vetter89dd6a42014-05-15 15:32:12 +02001319EXPORT_SYMBOL(drm_crtc_vblank_off);
1320
1321/**
Daniel Vetter96256042015-02-13 21:03:42 +01001322 * drm_crtc_vblank_reset - reset vblank state to off on a CRTC
Thierry Reding2b193f02015-09-24 18:35:30 +02001323 * @crtc: CRTC in question
Daniel Vetter96256042015-02-13 21:03:42 +01001324 *
1325 * Drivers can use this function to reset the vblank state to off at load time.
1326 * Drivers should use this together with the drm_crtc_vblank_off() and
1327 * drm_crtc_vblank_on() functions. The difference compared to
1328 * drm_crtc_vblank_off() is that this function doesn't save the vblank counter
1329 * and hence doesn't need to call any driver hooks.
1330 */
Thierry Reding2b193f02015-09-24 18:35:30 +02001331void drm_crtc_vblank_reset(struct drm_crtc *crtc)
Daniel Vetter96256042015-02-13 21:03:42 +01001332{
Thierry Reding2b193f02015-09-24 18:35:30 +02001333 struct drm_device *dev = crtc->dev;
Daniel Vetter96256042015-02-13 21:03:42 +01001334 unsigned long irqflags;
Thierry Reding2b193f02015-09-24 18:35:30 +02001335 unsigned int pipe = drm_crtc_index(crtc);
Ville Syrjälä1da248a2015-09-14 22:43:42 +03001336 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
Daniel Vetter96256042015-02-13 21:03:42 +01001337
1338 spin_lock_irqsave(&dev->vbl_lock, irqflags);
1339 /*
1340 * Prevent subsequent drm_vblank_get() from enabling the vblank
1341 * interrupt by bumping the refcount.
1342 */
1343 if (!vblank->inmodeset) {
1344 atomic_inc(&vblank->refcount);
1345 vblank->inmodeset = 1;
1346 }
1347 spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
1348
1349 WARN_ON(!list_empty(&dev->vblank_event_list));
1350}
1351EXPORT_SYMBOL(drm_crtc_vblank_reset);
1352
1353/**
Daniel Vetter2d1e3312016-11-14 10:02:54 +01001354 * drm_crtc_vblank_on - enable vblank events on a CRTC
1355 * @crtc: CRTC in question
Daniel Vetterf5752b32014-05-08 16:41:51 +02001356 *
1357 * This functions restores the vblank interrupt state captured with
Daniel Vetter2d1e3312016-11-14 10:02:54 +01001358 * drm_crtc_vblank_off() again. Note that calls to drm_crtc_vblank_on() and
1359 * drm_crtc_vblank_off() can be unbalanced and so can also be unconditionally called
Daniel Vetterf5752b32014-05-08 16:41:51 +02001360 * in driver load code to reflect the current hardware state of the crtc.
Ville Syrjäläf2752282014-02-19 21:29:49 +02001361 */
Daniel Vetter2d1e3312016-11-14 10:02:54 +01001362void drm_crtc_vblank_on(struct drm_crtc *crtc)
Ville Syrjäläf2752282014-02-19 21:29:49 +02001363{
Daniel Vetter2d1e3312016-11-14 10:02:54 +01001364 struct drm_device *dev = crtc->dev;
1365 unsigned int pipe = drm_crtc_index(crtc);
Thierry Redingcc1ef112015-08-12 17:00:31 +02001366 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
Ville Syrjäläf2752282014-02-19 21:29:49 +02001367 unsigned long irqflags;
1368
Thierry Redingcc1ef112015-08-12 17:00:31 +02001369 if (WARN_ON(pipe >= dev->num_crtcs))
Rob Clarke6ae8682014-08-06 13:16:59 -04001370 return;
1371
Ville Syrjäläf2752282014-02-19 21:29:49 +02001372 spin_lock_irqsave(&dev->vbl_lock, irqflags);
Mario Kleinere8235892016-02-12 20:30:27 +01001373 DRM_DEBUG_VBL("crtc %d, vblank enabled %d, inmodeset %d\n",
1374 pipe, vblank->enabled, vblank->inmodeset);
1375
Ville Syrjälä7ffd7a62014-08-06 14:49:44 +03001376 /* Drop our private "prevent drm_vblank_get" refcount */
Ville Syrjälä8a51d5b2014-08-06 14:49:50 +03001377 if (vblank->inmodeset) {
1378 atomic_dec(&vblank->refcount);
1379 vblank->inmodeset = 0;
Ville Syrjälä7ffd7a62014-08-06 14:49:44 +03001380 }
Ville Syrjäläf8ad0282014-08-06 14:49:49 +03001381
Ville Syrjälä4dfd6482015-09-14 22:43:51 +03001382 drm_reset_vblank_timestamp(dev, pipe);
1383
Ville Syrjäläcd19e522014-08-06 14:49:56 +03001384 /*
1385 * re-enable interrupts if there are users left, or the
1386 * user wishes vblank interrupts to be enabled all the time.
1387 */
Mario Kleinerbb74fc12016-02-12 20:30:30 +01001388 if (atomic_read(&vblank->refcount) != 0 || drm_vblank_offdelay == 0)
Thierry Redingcc1ef112015-08-12 17:00:31 +02001389 WARN_ON(drm_vblank_enable(dev, pipe));
Ville Syrjäläf2752282014-02-19 21:29:49 +02001390 spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
1391}
Daniel Vetter89dd6a42014-05-15 15:32:12 +02001392EXPORT_SYMBOL(drm_crtc_vblank_on);
1393
Daniel Vetter07600c52016-11-14 10:02:52 +01001394static void drm_legacy_vblank_pre_modeset(struct drm_device *dev,
1395 unsigned int pipe)
Dave Airlief453ba02008-11-07 14:05:41 -08001396{
Thierry Redingcc1ef112015-08-12 17:00:31 +02001397 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
Ville Syrjälä8a51d5b2014-08-06 14:49:50 +03001398
Huacai Chenb7ea85a2013-05-21 06:23:43 +00001399 /* vblank is not initialized (IRQ not installed ?), or has been freed */
Jerome Glissee77cef92010-01-07 15:39:13 +01001400 if (!dev->num_crtcs)
1401 return;
Rob Clarke6ae8682014-08-06 13:16:59 -04001402
Thierry Redingcc1ef112015-08-12 17:00:31 +02001403 if (WARN_ON(pipe >= dev->num_crtcs))
Rob Clarke6ae8682014-08-06 13:16:59 -04001404 return;
1405
Dave Airlief453ba02008-11-07 14:05:41 -08001406 /*
1407 * To avoid all the problems that might happen if interrupts
1408 * were enabled/disabled around or between these calls, we just
1409 * have the kernel take a reference on the CRTC (just once though
1410 * to avoid corrupting the count if multiple, mismatch calls occur),
1411 * so that interrupts remain enabled in the interim.
1412 */
Ville Syrjälä8a51d5b2014-08-06 14:49:50 +03001413 if (!vblank->inmodeset) {
1414 vblank->inmodeset = 0x1;
Thierry Redingcc1ef112015-08-12 17:00:31 +02001415 if (drm_vblank_get(dev, pipe) == 0)
Ville Syrjälä8a51d5b2014-08-06 14:49:50 +03001416 vblank->inmodeset |= 0x2;
Dave Airlief453ba02008-11-07 14:05:41 -08001417 }
1418}
Dave Airlief453ba02008-11-07 14:05:41 -08001419
Daniel Vetter07600c52016-11-14 10:02:52 +01001420static void drm_legacy_vblank_post_modeset(struct drm_device *dev,
1421 unsigned int pipe)
Dave Airlief453ba02008-11-07 14:05:41 -08001422{
Thierry Redingcc1ef112015-08-12 17:00:31 +02001423 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
Dave Airlief453ba02008-11-07 14:05:41 -08001424 unsigned long irqflags;
1425
Huacai Chenb7ea85a2013-05-21 06:23:43 +00001426 /* vblank is not initialized (IRQ not installed ?), or has been freed */
1427 if (!dev->num_crtcs)
1428 return;
1429
Thierry Redingcc1ef112015-08-12 17:00:31 +02001430 if (WARN_ON(pipe >= dev->num_crtcs))
Thierry Reding7d1de852015-08-12 17:00:30 +02001431 return;
1432
Ville Syrjälä8a51d5b2014-08-06 14:49:50 +03001433 if (vblank->inmodeset) {
Dave Airlief453ba02008-11-07 14:05:41 -08001434 spin_lock_irqsave(&dev->vbl_lock, irqflags);
Mario Kleinerc61934e2016-02-12 20:30:29 +01001435 drm_reset_vblank_timestamp(dev, pipe);
Dave Airlief453ba02008-11-07 14:05:41 -08001436 spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
Chris Wilsonb3f5e732009-02-19 14:48:22 +00001437
Ville Syrjälä8a51d5b2014-08-06 14:49:50 +03001438 if (vblank->inmodeset & 0x2)
Thierry Redingcc1ef112015-08-12 17:00:31 +02001439 drm_vblank_put(dev, pipe);
Chris Wilsonb3f5e732009-02-19 14:48:22 +00001440
Ville Syrjälä8a51d5b2014-08-06 14:49:50 +03001441 vblank->inmodeset = 0;
Dave Airlief453ba02008-11-07 14:05:41 -08001442 }
1443}
Dave Airlief453ba02008-11-07 14:05:41 -08001444
Daniel Vetterf5752b32014-05-08 16:41:51 +02001445/*
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001446 * drm_modeset_ctl - handle vblank event counter changes across mode switch
1447 * @DRM_IOCTL_ARGS: standard ioctl arguments
1448 *
1449 * Applications should call the %_DRM_PRE_MODESET and %_DRM_POST_MODESET
1450 * ioctls around modesetting so that any lost vblank events are accounted for.
1451 *
1452 * Generally the counter will reset across mode sets. If interrupts are
1453 * enabled around this call, we don't have to do anything since the counter
1454 * will have already been incremented.
1455 */
1456int drm_modeset_ctl(struct drm_device *dev, void *data,
1457 struct drm_file *file_priv)
1458{
1459 struct drm_modeset_ctl *modeset = data;
Thierry Redingcc1ef112015-08-12 17:00:31 +02001460 unsigned int pipe;
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001461
1462 /* If drm_vblank_init() hasn't been called yet, just no-op */
1463 if (!dev->num_crtcs)
Laurent Pinchart4a1b0712012-05-17 13:27:21 +02001464 return 0;
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001465
Laurent Pinchart29935552012-05-30 00:58:09 +02001466 /* KMS drivers handle this internally */
Daniel Vetterfa538642016-08-03 21:11:10 +02001467 if (!drm_core_check_feature(dev, DRIVER_LEGACY))
Laurent Pinchart29935552012-05-30 00:58:09 +02001468 return 0;
1469
Thierry Redingcc1ef112015-08-12 17:00:31 +02001470 pipe = modeset->crtc;
1471 if (pipe >= dev->num_crtcs)
Laurent Pinchart4a1b0712012-05-17 13:27:21 +02001472 return -EINVAL;
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001473
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001474 switch (modeset->cmd) {
1475 case _DRM_PRE_MODESET:
Daniel Vetter07600c52016-11-14 10:02:52 +01001476 drm_legacy_vblank_pre_modeset(dev, pipe);
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001477 break;
1478 case _DRM_POST_MODESET:
Daniel Vetter07600c52016-11-14 10:02:52 +01001479 drm_legacy_vblank_post_modeset(dev, pipe);
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001480 break;
1481 default:
Laurent Pinchart4a1b0712012-05-17 13:27:21 +02001482 return -EINVAL;
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001483 }
1484
Laurent Pinchart4a1b0712012-05-17 13:27:21 +02001485 return 0;
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001486}
1487
Thierry Redingcc1ef112015-08-12 17:00:31 +02001488static int drm_queue_vblank_event(struct drm_device *dev, unsigned int pipe,
Kristian Høgsbergc9a9c5e2009-09-12 04:33:34 +10001489 union drm_wait_vblank *vblwait,
1490 struct drm_file *file_priv)
1491{
Ville Syrjäläffe7c732014-08-06 14:49:52 +03001492 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
Kristian Høgsbergc9a9c5e2009-09-12 04:33:34 +10001493 struct drm_pending_vblank_event *e;
1494 struct timeval now;
1495 unsigned long flags;
1496 unsigned int seq;
Chris Wilsonea5d5522010-12-01 19:41:31 +00001497 int ret;
Kristian Høgsbergc9a9c5e2009-09-12 04:33:34 +10001498
Thierry Redingf76511b2014-12-10 13:03:40 +01001499 e = kzalloc(sizeof(*e), GFP_KERNEL);
Chris Wilsonea5d5522010-12-01 19:41:31 +00001500 if (e == NULL) {
1501 ret = -ENOMEM;
1502 goto err_put;
1503 }
Kristian Høgsbergc9a9c5e2009-09-12 04:33:34 +10001504
1505 e->pipe = pipe;
Jesse Barnesb9c2c9a2010-07-01 16:48:09 -07001506 e->base.pid = current->pid;
Kristian Høgsbergc9a9c5e2009-09-12 04:33:34 +10001507 e->event.base.type = DRM_EVENT_VBLANK;
Thierry Redingf76511b2014-12-10 13:03:40 +01001508 e->event.base.length = sizeof(e->event);
Kristian Høgsbergc9a9c5e2009-09-12 04:33:34 +10001509 e->event.user_data = vblwait->request.signal;
Kristian Høgsbergc9a9c5e2009-09-12 04:33:34 +10001510
Kristian Høgsbergc9a9c5e2009-09-12 04:33:34 +10001511 spin_lock_irqsave(&dev->event_lock, flags);
1512
Ville Syrjäläffe7c732014-08-06 14:49:52 +03001513 /*
Daniel Vetter2d1e3312016-11-14 10:02:54 +01001514 * drm_crtc_vblank_off() might have been called after we called
1515 * drm_vblank_get(). drm_crtc_vblank_off() holds event_lock around the
1516 * vblank disable, so no need for further locking. The reference from
1517 * drm_vblank_get() protects against vblank disable from another source.
Ville Syrjäläffe7c732014-08-06 14:49:52 +03001518 */
1519 if (!vblank->enabled) {
1520 ret = -EINVAL;
1521 goto err_unlock;
1522 }
1523
Daniel Vetter4020b222016-01-28 12:01:04 +01001524 ret = drm_event_reserve_init_locked(dev, file_priv, &e->base,
1525 &e->event.base);
Kristian Høgsbergc9a9c5e2009-09-12 04:33:34 +10001526
Daniel Vetter4020b222016-01-28 12:01:04 +01001527 if (ret)
1528 goto err_unlock;
1529
Mario Kleiner27641c32010-10-23 04:20:23 +02001530 seq = drm_vblank_count_and_time(dev, pipe, &now);
1531
Rodrigo Vivi1d776852016-08-03 09:53:46 -07001532 DRM_DEBUG("event on vblank count %u, current %u, crtc %u\n",
Kristian Høgsbergc9a9c5e2009-09-12 04:33:34 +10001533 vblwait->request.sequence, seq, pipe);
1534
Jesse Barnesb9c2c9a2010-07-01 16:48:09 -07001535 trace_drm_vblank_event_queued(current->pid, pipe,
1536 vblwait->request.sequence);
1537
Kristian Høgsbergc9a9c5e2009-09-12 04:33:34 +10001538 e->event.sequence = vblwait->request.sequence;
1539 if ((seq - vblwait->request.sequence) <= (1 << 23)) {
Dan Carpenter6f331622010-12-09 08:35:40 +03001540 drm_vblank_put(dev, pipe);
Rob Clarkc6eefa12012-10-16 22:48:40 +00001541 send_vblank_event(dev, e, seq, &now);
Mario Kleiner000fa7c2010-12-10 16:00:19 +01001542 vblwait->reply.sequence = seq;
Kristian Høgsbergc9a9c5e2009-09-12 04:33:34 +10001543 } else {
Ilija Hadzica6778e92011-10-31 13:11:57 -04001544 /* drm_handle_vblank_events will call drm_vblank_put */
Kristian Høgsbergc9a9c5e2009-09-12 04:33:34 +10001545 list_add_tail(&e->base.link, &dev->vblank_event_list);
Mario Kleiner000fa7c2010-12-10 16:00:19 +01001546 vblwait->reply.sequence = vblwait->request.sequence;
Kristian Høgsbergc9a9c5e2009-09-12 04:33:34 +10001547 }
1548
1549 spin_unlock_irqrestore(&dev->event_lock, flags);
1550
1551 return 0;
Chris Wilsonea5d5522010-12-01 19:41:31 +00001552
1553err_unlock:
1554 spin_unlock_irqrestore(&dev->event_lock, flags);
1555 kfree(e);
1556err_put:
Dan Carpenter6f331622010-12-09 08:35:40 +03001557 drm_vblank_put(dev, pipe);
Chris Wilsonea5d5522010-12-01 19:41:31 +00001558 return ret;
Kristian Høgsbergc9a9c5e2009-09-12 04:33:34 +10001559}
1560
Daniel Vetterf5752b32014-05-08 16:41:51 +02001561/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07001562 * Wait for VBLANK.
1563 *
1564 * \param inode device inode.
Eric Anholt6c340ea2007-08-25 20:23:09 +10001565 * \param file_priv DRM file private.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001566 * \param cmd command.
1567 * \param data user argument, pointing to a drm_wait_vblank structure.
1568 * \return zero on success or a negative number on failure.
1569 *
Eric Anholt30b23632009-01-27 21:19:41 -08001570 * This function enables the vblank interrupt on the pipe requested, then
1571 * sleeps waiting for the requested sequence number to occur, and drops
Daniel Vetterf5752b32014-05-08 16:41:51 +02001572 * the vblank interrupt refcount afterwards. (vblank IRQ disable follows that
Eric Anholt30b23632009-01-27 21:19:41 -08001573 * after a timeout with no further vblank waits scheduled).
Linus Torvalds1da177e2005-04-16 15:20:36 -07001574 */
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001575int drm_wait_vblank(struct drm_device *dev, void *data,
1576 struct drm_file *file_priv)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001577{
Ville Syrjälä8a51d5b2014-08-06 14:49:50 +03001578 struct drm_vblank_crtc *vblank;
Eric Anholtc153f452007-09-03 12:06:45 +10001579 union drm_wait_vblank *vblwait = data;
Laurent Pinchart4a1b0712012-05-17 13:27:21 +02001580 int ret;
Thierry Redingcc1ef112015-08-12 17:00:31 +02001581 unsigned int flags, seq, pipe, high_pipe;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001582
Daniel Vetter49849792013-08-28 15:02:37 +02001583 if (!dev->irq_enabled)
1584 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001585
Eric Anholt30b23632009-01-27 21:19:41 -08001586 if (vblwait->request.type & _DRM_VBLANK_SIGNAL)
1587 return -EINVAL;
1588
Eric Anholtc153f452007-09-03 12:06:45 +10001589 if (vblwait->request.type &
Ilija Hadzic19b01b52011-03-18 16:58:04 -05001590 ~(_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK |
1591 _DRM_VBLANK_HIGH_CRTC_MASK)) {
=?utf-8?q?Michel_D=C3=A4nzer?=776c9442006-10-24 22:24:38 +10001592 DRM_ERROR("Unsupported type value 0x%x, supported mask 0x%x\n",
Eric Anholtc153f452007-09-03 12:06:45 +10001593 vblwait->request.type,
Ilija Hadzic19b01b52011-03-18 16:58:04 -05001594 (_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK |
1595 _DRM_VBLANK_HIGH_CRTC_MASK));
=?utf-8?q?Michel_D=C3=A4nzer?=776c9442006-10-24 22:24:38 +10001596 return -EINVAL;
1597 }
1598
Eric Anholtc153f452007-09-03 12:06:45 +10001599 flags = vblwait->request.type & _DRM_VBLANK_FLAGS_MASK;
Thierry Redingcc1ef112015-08-12 17:00:31 +02001600 high_pipe = (vblwait->request.type & _DRM_VBLANK_HIGH_CRTC_MASK);
1601 if (high_pipe)
1602 pipe = high_pipe >> _DRM_VBLANK_HIGH_CRTC_SHIFT;
Ilija Hadzic19b01b52011-03-18 16:58:04 -05001603 else
Thierry Redingcc1ef112015-08-12 17:00:31 +02001604 pipe = flags & _DRM_VBLANK_SECONDARY ? 1 : 0;
1605 if (pipe >= dev->num_crtcs)
=?utf-8?q?Michel_D=C3=A4nzer?=776c9442006-10-24 22:24:38 +10001606 return -EINVAL;
1607
Thierry Redingcc1ef112015-08-12 17:00:31 +02001608 vblank = &dev->vblank[pipe];
Ville Syrjälä8a51d5b2014-08-06 14:49:50 +03001609
Thierry Redingcc1ef112015-08-12 17:00:31 +02001610 ret = drm_vblank_get(dev, pipe);
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001611 if (ret) {
Paul Rolland8d3457e2009-08-09 12:24:01 +10001612 DRM_DEBUG("failed to acquire vblank counter, %d\n", ret);
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001613 return ret;
1614 }
Thierry Redingcc1ef112015-08-12 17:00:31 +02001615 seq = drm_vblank_count(dev, pipe);
=?utf-8?q?Michel_D=C3=A4nzer?=776c9442006-10-24 22:24:38 +10001616
Eric Anholtc153f452007-09-03 12:06:45 +10001617 switch (vblwait->request.type & _DRM_VBLANK_TYPES_MASK) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001618 case _DRM_VBLANK_RELATIVE:
Eric Anholtc153f452007-09-03 12:06:45 +10001619 vblwait->request.sequence += seq;
1620 vblwait->request.type &= ~_DRM_VBLANK_RELATIVE;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001621 case _DRM_VBLANK_ABSOLUTE:
1622 break;
1623 default:
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001624 ret = -EINVAL;
1625 goto done;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001626 }
1627
Michel Dänzer97ef1ae2016-06-24 16:59:47 +09001628 if ((flags & _DRM_VBLANK_NEXTONMISS) &&
1629 (seq - vblwait->request.sequence) <= (1 << 23)) {
1630 vblwait->request.sequence = seq + 1;
1631 }
1632
Ilija Hadzica6778e92011-10-31 13:11:57 -04001633 if (flags & _DRM_VBLANK_EVENT) {
1634 /* must hold on to the vblank ref until the event fires
1635 * drm_vblank_put will be called asynchronously
1636 */
Thierry Redingcc1ef112015-08-12 17:00:31 +02001637 return drm_queue_vblank_event(dev, pipe, vblwait, file_priv);
Ilija Hadzica6778e92011-10-31 13:11:57 -04001638 }
Kristian Høgsbergc9a9c5e2009-09-12 04:33:34 +10001639
Rodrigo Vivi1d776852016-08-03 09:53:46 -07001640 DRM_DEBUG("waiting on vblank count %u, crtc %u\n",
Thierry Redingcc1ef112015-08-12 17:00:31 +02001641 vblwait->request.sequence, pipe);
Ville Syrjälä8a51d5b2014-08-06 14:49:50 +03001642 DRM_WAIT_ON(ret, vblank->queue, 3 * HZ,
Thierry Redingcc1ef112015-08-12 17:00:31 +02001643 (((drm_vblank_count(dev, pipe) -
Eric Anholt30b23632009-01-27 21:19:41 -08001644 vblwait->request.sequence) <= (1 << 23)) ||
Ville Syrjälä8a51d5b2014-08-06 14:49:50 +03001645 !vblank->enabled ||
Eric Anholt30b23632009-01-27 21:19:41 -08001646 !dev->irq_enabled));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001647
Eric Anholt30b23632009-01-27 21:19:41 -08001648 if (ret != -EINTR) {
1649 struct timeval now;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001650
Thierry Redingcc1ef112015-08-12 17:00:31 +02001651 vblwait->reply.sequence = drm_vblank_count_and_time(dev, pipe, &now);
Eric Anholt30b23632009-01-27 21:19:41 -08001652 vblwait->reply.tval_sec = now.tv_sec;
1653 vblwait->reply.tval_usec = now.tv_usec;
Mario Kleiner27641c32010-10-23 04:20:23 +02001654
Rodrigo Vivi1d776852016-08-03 09:53:46 -07001655 DRM_DEBUG("returning %u to client\n",
Eric Anholt30b23632009-01-27 21:19:41 -08001656 vblwait->reply.sequence);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001657 } else {
Eric Anholt30b23632009-01-27 21:19:41 -08001658 DRM_DEBUG("vblank wait interrupted by signal\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001659 }
1660
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001661done:
Thierry Redingcc1ef112015-08-12 17:00:31 +02001662 drm_vblank_put(dev, pipe);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001663 return ret;
1664}
1665
Thierry Redingcc1ef112015-08-12 17:00:31 +02001666static void drm_handle_vblank_events(struct drm_device *dev, unsigned int pipe)
Kristian Høgsbergc9a9c5e2009-09-12 04:33:34 +10001667{
1668 struct drm_pending_vblank_event *e, *t;
1669 struct timeval now;
Kristian Høgsbergc9a9c5e2009-09-12 04:33:34 +10001670 unsigned int seq;
1671
Ville Syrjälä56cc2792014-08-06 14:49:51 +03001672 assert_spin_locked(&dev->event_lock);
Kristian Høgsbergc9a9c5e2009-09-12 04:33:34 +10001673
Thierry Redingcc1ef112015-08-12 17:00:31 +02001674 seq = drm_vblank_count_and_time(dev, pipe, &now);
Kristian Høgsbergc9a9c5e2009-09-12 04:33:34 +10001675
1676 list_for_each_entry_safe(e, t, &dev->vblank_event_list, base.link) {
Thierry Redingcc1ef112015-08-12 17:00:31 +02001677 if (e->pipe != pipe)
Kristian Høgsbergc9a9c5e2009-09-12 04:33:34 +10001678 continue;
1679 if ((seq - e->event.sequence) > (1<<23))
1680 continue;
1681
Rodrigo Vivi1d776852016-08-03 09:53:46 -07001682 DRM_DEBUG("vblank event on %u, current %u\n",
Kristian Høgsbergc9a9c5e2009-09-12 04:33:34 +10001683 e->event.sequence, seq);
1684
Rob Clarkc6eefa12012-10-16 22:48:40 +00001685 list_del(&e->base.link);
Thierry Redingcc1ef112015-08-12 17:00:31 +02001686 drm_vblank_put(dev, pipe);
Rob Clarkc6eefa12012-10-16 22:48:40 +00001687 send_vblank_event(dev, e, seq, &now);
Kristian Høgsbergc9a9c5e2009-09-12 04:33:34 +10001688 }
1689
Thierry Redingcc1ef112015-08-12 17:00:31 +02001690 trace_drm_vblank_event(pipe, seq);
Kristian Høgsbergc9a9c5e2009-09-12 04:33:34 +10001691}
1692
Linus Torvalds1da177e2005-04-16 15:20:36 -07001693/**
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001694 * drm_handle_vblank - handle a vblank event
1695 * @dev: DRM device
Thierry Redingcc1ef112015-08-12 17:00:31 +02001696 * @pipe: index of CRTC where this event occurred
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001697 *
1698 * Drivers should call this routine in their vblank interrupt handlers to
1699 * update the vblank counter and send any signals that may be pending.
Thierry Reding115ebcd2014-12-15 14:47:18 +01001700 *
1701 * This is the legacy version of drm_crtc_handle_vblank().
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001702 */
Thierry Redingcc1ef112015-08-12 17:00:31 +02001703bool drm_handle_vblank(struct drm_device *dev, unsigned int pipe)
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001704{
Thierry Redingcc1ef112015-08-12 17:00:31 +02001705 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
Mario Kleiner27641c32010-10-23 04:20:23 +02001706 unsigned long irqflags;
1707
Daniel Vetteree3c7792015-02-22 15:11:20 +01001708 if (WARN_ON_ONCE(!dev->num_crtcs))
Chris Wilson78c6e172011-01-31 10:48:04 +00001709 return false;
Kristian Høgsbergc9a9c5e2009-09-12 04:33:34 +10001710
Thierry Redingcc1ef112015-08-12 17:00:31 +02001711 if (WARN_ON(pipe >= dev->num_crtcs))
Rob Clarke6ae8682014-08-06 13:16:59 -04001712 return false;
1713
Ville Syrjälä56cc2792014-08-06 14:49:51 +03001714 spin_lock_irqsave(&dev->event_lock, irqflags);
1715
Mario Kleiner27641c32010-10-23 04:20:23 +02001716 /* Need timestamp lock to prevent concurrent execution with
1717 * vblank enable/disable, as this would cause inconsistent
1718 * or corrupted timestamps and vblank counts.
1719 */
Ville Syrjälä56cc2792014-08-06 14:49:51 +03001720 spin_lock(&dev->vblank_time_lock);
Mario Kleiner27641c32010-10-23 04:20:23 +02001721
1722 /* Vblank irq handling disabled. Nothing to do. */
Ville Syrjälä8a51d5b2014-08-06 14:49:50 +03001723 if (!vblank->enabled) {
Ville Syrjälä56cc2792014-08-06 14:49:51 +03001724 spin_unlock(&dev->vblank_time_lock);
1725 spin_unlock_irqrestore(&dev->event_lock, irqflags);
Chris Wilson78c6e172011-01-31 10:48:04 +00001726 return false;
Mario Kleiner27641c32010-10-23 04:20:23 +02001727 }
1728
Ville Syrjälä4dfd6482015-09-14 22:43:51 +03001729 drm_update_vblank_count(dev, pipe, DRM_CALLED_FROM_VBLIRQ);
Mario Kleiner27641c32010-10-23 04:20:23 +02001730
Ville Syrjälä56cc2792014-08-06 14:49:51 +03001731 spin_unlock(&dev->vblank_time_lock);
1732
Ville Syrjälä8a51d5b2014-08-06 14:49:50 +03001733 wake_up(&vblank->queue);
Thierry Redingcc1ef112015-08-12 17:00:31 +02001734 drm_handle_vblank_events(dev, pipe);
Mario Kleiner27641c32010-10-23 04:20:23 +02001735
Ville Syrjälä56cc2792014-08-06 14:49:51 +03001736 spin_unlock_irqrestore(&dev->event_lock, irqflags);
1737
Chris Wilson78c6e172011-01-31 10:48:04 +00001738 return true;
Jesse Barnes0a3e67a2008-09-30 12:14:26 -07001739}
1740EXPORT_SYMBOL(drm_handle_vblank);
Thierry Reding115ebcd2014-12-15 14:47:18 +01001741
1742/**
1743 * drm_crtc_handle_vblank - handle a vblank event
1744 * @crtc: where this event occurred
1745 *
1746 * Drivers should call this routine in their vblank interrupt handlers to
1747 * update the vblank counter and send any signals that may be pending.
1748 *
1749 * This is the native KMS version of drm_handle_vblank().
1750 *
1751 * Returns:
1752 * True if the event was successfully handled, false on failure.
1753 */
1754bool drm_crtc_handle_vblank(struct drm_crtc *crtc)
1755{
1756 return drm_handle_vblank(crtc->dev, drm_crtc_index(crtc));
1757}
1758EXPORT_SYMBOL(drm_crtc_handle_vblank);
Ville Syrjäläb44f8402015-09-30 16:46:48 +03001759
1760/**
1761 * drm_vblank_no_hw_counter - "No hw counter" implementation of .get_vblank_counter()
1762 * @dev: DRM device
1763 * @pipe: CRTC for which to read the counter
1764 *
1765 * Drivers can plug this into the .get_vblank_counter() function if
1766 * there is no useable hardware frame counter available.
1767 *
1768 * Returns:
1769 * 0
1770 */
1771u32 drm_vblank_no_hw_counter(struct drm_device *dev, unsigned int pipe)
1772{
Daniel Vettercfc5ade2016-08-08 18:24:53 +02001773 WARN_ON_ONCE(dev->max_vblank_count != 0);
Ville Syrjäläb44f8402015-09-30 16:46:48 +03001774 return 0;
1775}
1776EXPORT_SYMBOL(drm_vblank_no_hw_counter);