drivers/gpu/drm/drm_irq.c

   1 /**
   2  * \file drm_irq.c
   3  * IRQ support
   4  *
   5  * \author Rickard E. (Rik) Faith <faith@valinux.com>
   6  * \author Gareth Hughes <gareth@valinux.com>
   7  */
   8
   9 /*
  10  * Created: Fri Mar 19 14:30:16 1999 by faith@valinux.com
  11  *
  12  * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
  13  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
  14  * All Rights Reserved.
  15  *
  16  * Permission is hereby granted, free of charge, to any person obtaining a
  17  * copy of this software and associated documentation files (the "Software"),
  18  * to deal in the Software without restriction, including without limitation
  19  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  20  * and/or sell copies of the Software, and to permit persons to whom the
  21  * Software is furnished to do so, subject to the following conditions:
  22  *
  23  * The above copyright notice and this permission notice (including the next
  24  * paragraph) shall be included in all copies or substantial portions of the
  25  * Software.
  26  *
  27  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  28  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  29  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  30  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  31  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  32  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  33  * OTHER DEALINGS IN THE SOFTWARE.
  34  */
  35
  36 #include "drmP.h"
  37
  38 #include <linux/interrupt.h>    /* For task queue support */
  39
  40 /**
  41  * Get interrupt from bus id.
  42  *
  43  * \param inode device inode.
  44  * \param file_priv DRM file private.
  45  * \param cmd command.
  46  * \param arg user argument, pointing to a drm_irq_busid structure.
  47  * \return zero on success or a negative number on failure.
  48  *
  49  * Finds the PCI device with the specified bus id and gets its IRQ number.
  50  * This IOCTL is deprecated, and will now return EINVAL for any busid not equal
  51  * to that of the device that this DRM instance attached to.
  52  */
  53 int drm_irq_by_busid(struct drm_device *dev, void *data,
  54                      struct drm_file *file_priv)
  55 {
  56         struct drm_irq_busid *p = data;
  57
  58         if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
  59                 return -EINVAL;
  60
  61         if ((p->busnum >> 8) != drm_get_pci_domain(dev) ||
  62             (p->busnum & 0xff) != dev->pdev->bus->number ||
  63             p->devnum != PCI_SLOT(dev->pdev->devfn) || p->funcnum != PCI_FUNC(dev->pdev->devfn))
  64                 return -EINVAL;
  65
  66         p->irq = dev->pdev->irq;
  67
  68         DRM_DEBUG("%d:%d:%d => IRQ %d\n", p->busnum, p->devnum, p->funcnum,
  69                   p->irq);
  70
  71         return 0;
  72 }
  73
  74 static void vblank_disable_fn(unsigned long arg)
  75 {
  76         struct drm_device *dev = (struct drm_device *)arg;
  77         unsigned long irqflags;
  78         int i;
  79
  80         if (!dev->vblank_disable_allowed)
  81                 return;
  82
  83         for (i = 0; i < dev->num_crtcs; i++) {
  84                 spin_lock_irqsave(&dev->vbl_lock, irqflags);
  85                 if (atomic_read(&dev->vblank_refcount[i]) == 0 &&
  86                     dev->vblank_enabled[i]) {
  87                         DRM_DEBUG("disabling vblank on crtc %d\n", i);
  88                         dev->last_vblank[i] =
  89                                 dev->driver->get_vblank_counter(dev, i);
  90                         dev->driver->disable_vblank(dev, i);
  91                         dev->vblank_enabled[i] = 0;
  92                 }
  93                 spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
  94         }
  95 }
  96
  97 void drm_vblank_cleanup(struct drm_device *dev)
  98 {
  99         /* Bail if the driver didn't call drm_vblank_init() */
 100         if (dev->num_crtcs == 0)
 101                 return;
 102
 103         del_timer(&dev->vblank_disable_timer);
 104
 105         vblank_disable_fn((unsigned long)dev);
 106
 107         kfree(dev->vbl_queue);
 108         kfree(dev->_vblank_count);
 109         kfree(dev->vblank_refcount);
 110         kfree(dev->vblank_enabled);
 111         kfree(dev->last_vblank);
 112         kfree(dev->last_vblank_wait);
 113         kfree(dev->vblank_inmodeset);
 114
 115         dev->num_crtcs = 0;
 116 }
 117
 118 int drm_vblank_init(struct drm_device *dev, int num_crtcs)
 119 {
 120         int i, ret = -ENOMEM;
 121
 122         setup_timer(&dev->vblank_disable_timer, vblank_disable_fn,
 123                     (unsigned long)dev);
 124         spin_lock_init(&dev->vbl_lock);
 125         dev->num_crtcs = num_crtcs;
 126
 127         dev->vbl_queue = kmalloc(sizeof(wait_queue_head_t) * num_crtcs,
 128                                  GFP_KERNEL);
 129         if (!dev->vbl_queue)
 130                 goto err;
 131
 132         dev->_vblank_count = kmalloc(sizeof(atomic_t) * num_crtcs, GFP_KERNEL);
 133         if (!dev->_vblank_count)
 134                 goto err;
 135
 136         dev->vblank_refcount = kmalloc(sizeof(atomic_t) * num_crtcs,
 137                                        GFP_KERNEL);
 138         if (!dev->vblank_refcount)
 139                 goto err;
 140
 141         dev->vblank_enabled = kcalloc(num_crtcs, sizeof(int), GFP_KERNEL);
 142         if (!dev->vblank_enabled)
 143                 goto err;
 144
 145         dev->last_vblank = kcalloc(num_crtcs, sizeof(u32), GFP_KERNEL);
 146         if (!dev->last_vblank)
 147                 goto err;
 148
 149         dev->last_vblank_wait = kcalloc(num_crtcs, sizeof(u32), GFP_KERNEL);
 150         if (!dev->last_vblank_wait)
 151                 goto err;
 152
 153         dev->vblank_inmodeset = kcalloc(num_crtcs, sizeof(int), GFP_KERNEL);
 154         if (!dev->vblank_inmodeset)
 155                 goto err;
 156
 157         /* Zero per-crtc vblank stuff */
 158         for (i = 0; i < num_crtcs; i++) {
 159                 init_waitqueue_head(&dev->vbl_queue[i]);
 160                 atomic_set(&dev->_vblank_count[i], 0);
 161                 atomic_set(&dev->vblank_refcount[i], 0);
 162         }
 163
 164         dev->vblank_disable_allowed = 0;
 165
 166         return 0;
 167
 168 err:
 169         drm_vblank_cleanup(dev);
 170         return ret;
 171 }
 172 EXPORT_SYMBOL(drm_vblank_init);
 173
 174 /**
 175  * Install IRQ handler.
 176  *
 177  * \param dev DRM device.
 178  *
 179  * Initializes the IRQ related data. Installs the handler, calling the driver
 180  * \c drm_driver_irq_preinstall() and \c drm_driver_irq_postinstall() functions
 181  * before and after the installation.
 182  */
 183 int drm_irq_install(struct drm_device *dev)
 184 {
 185         int ret = 0;
 186         unsigned long sh_flags = 0;
 187         char *irqname;
 188
 189         if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
 190                 return -EINVAL;
 191
 192         if (dev->pdev->irq == 0)
 193                 return -EINVAL;
 194
 195         mutex_lock(&dev->struct_mutex);
 196
 197         /* Driver must have been initialized */
 198         if (!dev->dev_private) {
 199                 mutex_unlock(&dev->struct_mutex);
 200                 return -EINVAL;
 201         }
 202
 203         if (dev->irq_enabled) {
 204                 mutex_unlock(&dev->struct_mutex);
 205                 return -EBUSY;
 206         }
 207         dev->irq_enabled = 1;
 208         mutex_unlock(&dev->struct_mutex);
 209
 210         DRM_DEBUG("irq=%d\n", dev->pdev->irq);
 211
 212         /* Before installing handler */
 213         dev->driver->irq_preinstall(dev);
 214
 215         /* Install handler */
 216         if (drm_core_check_feature(dev, DRIVER_IRQ_SHARED))
 217                 sh_flags = IRQF_SHARED;
 218
 219         if (dev->devname)
 220                 irqname = dev->devname;
 221         else
 222                 irqname = dev->driver->name;
 223
 224         ret = request_irq(drm_dev_to_irq(dev), dev->driver->irq_handler,
 225                           sh_flags, irqname, dev);
 226
 227         if (ret < 0) {
 228                 mutex_lock(&dev->struct_mutex);
 229                 dev->irq_enabled = 0;
 230                 mutex_unlock(&dev->struct_mutex);
 231                 return ret;
 232         }
 233
 234         /* After installing handler */
 235         ret = dev->driver->irq_postinstall(dev);
 236         if (ret < 0) {
 237                 mutex_lock(&dev->struct_mutex);
 238                 dev->irq_enabled = 0;
 239                 mutex_unlock(&dev->struct_mutex);
 240         }
 241
 242         return ret;
 243 }
 244 EXPORT_SYMBOL(drm_irq_install);
 245
 246 /**
 247  * Uninstall the IRQ handler.
 248  *
 249  * \param dev DRM device.
 250  *
 251  * Calls the driver's \c drm_driver_irq_uninstall() function, and stops the irq.
 252  */
 253 int drm_irq_uninstall(struct drm_device * dev)
 254 {
 255         unsigned long irqflags;
 256         int irq_enabled, i;
 257
 258         if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
 259                 return -EINVAL;
 260
 261         mutex_lock(&dev->struct_mutex);
 262         irq_enabled = dev->irq_enabled;
 263         dev->irq_enabled = 0;
 264         mutex_unlock(&dev->struct_mutex);
 265
 266         /*
 267          * Wake up any waiters so they don't hang.
 268          */
 269         spin_lock_irqsave(&dev->vbl_lock, irqflags);
 270         for (i = 0; i < dev->num_crtcs; i++) {
 271                 DRM_WAKEUP(&dev->vbl_queue[i]);
 272                 dev->vblank_enabled[i] = 0;
 273                 dev->last_vblank[i] = dev->driver->get_vblank_counter(dev, i);
 274         }
 275         spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
 276
 277         if (!irq_enabled)
 278                 return -EINVAL;
 279
 280         DRM_DEBUG("irq=%d\n", dev->pdev->irq);
 281
 282         dev->driver->irq_uninstall(dev);
 283
 284         free_irq(dev->pdev->irq, dev);
 285
 286         return 0;
 287 }
 288 EXPORT_SYMBOL(drm_irq_uninstall);
 289
 290 /**
 291  * IRQ control ioctl.
 292  *
 293  * \param inode device inode.
 294  * \param file_priv DRM file private.
 295  * \param cmd command.
 296  * \param arg user argument, pointing to a drm_control structure.
 297  * \return zero on success or a negative number on failure.
 298  *
 299  * Calls irq_install() or irq_uninstall() according to \p arg.
 300  */
 301 int drm_control(struct drm_device *dev, void *data,
 302                 struct drm_file *file_priv)
 303 {
 304         struct drm_control *ctl = data;
 305
 306         /* if we haven't irq we fallback for compatibility reasons - this used to be a separate function in drm_dma.h */
 307
 308
 309         switch (ctl->func) {
 310         case DRM_INST_HANDLER:
 311                 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
 312                         return 0;
 313                 if (drm_core_check_feature(dev, DRIVER_MODESET))
 314                         return 0;
 315                 if (dev->if_version < DRM_IF_VERSION(1, 2) &&
 316                     ctl->irq != dev->pdev->irq)
 317                         return -EINVAL;
 318                 return drm_irq_install(dev);
 319         case DRM_UNINST_HANDLER:
 320                 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
 321                         return 0;
 322                 if (drm_core_check_feature(dev, DRIVER_MODESET))
 323                         return 0;
 324                 return drm_irq_uninstall(dev);
 325         default:
 326                 return -EINVAL;
 327         }
 328 }
 329
 330 /**
 331  * drm_vblank_count - retrieve "cooked" vblank counter value
 332  * @dev: DRM device
 333  * @crtc: which counter to retrieve
 334  *
 335  * Fetches the "cooked" vblank count value that represents the number of
 336  * vblank events since the system was booted, including lost events due to
 337  * modesetting activity.
 338  */
 339 u32 drm_vblank_count(struct drm_device *dev, int crtc)
 340 {
 341         return atomic_read(&dev->_vblank_count[crtc]);
 342 }
 343 EXPORT_SYMBOL(drm_vblank_count);
 344
 345 /**
 346  * drm_update_vblank_count - update the master vblank counter
 347  * @dev: DRM device
 348  * @crtc: counter to update
 349  *
 350  * Call back into the driver to update the appropriate vblank counter
 351  * (specified by @crtc).  Deal with wraparound, if it occurred, and
 352  * update the last read value so we can deal with wraparound on the next
 353  * call if necessary.
 354  *
 355  * Only necessary when going from off->on, to account for frames we
 356  * didn't get an interrupt for.
 357  *
 358  * Note: caller must hold dev->vbl_lock since this reads & writes
 359  * device vblank fields.
 360  */
 361 static void drm_update_vblank_count(struct drm_device *dev, int crtc)
 362 {
 363         u32 cur_vblank, diff;
 364
 365         /*
 366          * Interrupts were disabled prior to this call, so deal with counter
 367          * wrap if needed.
 368          * NOTE!  It's possible we lost a full dev->max_vblank_count events
 369          * here if the register is small or we had vblank interrupts off for
 370          * a long time.
 371          */
 372         cur_vblank = dev->driver->get_vblank_counter(dev, crtc);
 373         diff = cur_vblank - dev->last_vblank[crtc];
 374         if (cur_vblank < dev->last_vblank[crtc]) {
 375                 diff += dev->max_vblank_count;
 376
 377                 DRM_DEBUG("last_vblank[%d]=0x%x, cur_vblank=0x%x => diff=0x%x\n",
 378                           crtc, dev->last_vblank[crtc], cur_vblank, diff);
 379         }
 380
 381         DRM_DEBUG("enabling vblank interrupts on crtc %d, missed %d\n",
 382                   crtc, diff);
 383
 384         atomic_add(diff, &dev->_vblank_count[crtc]);
 385 }
 386
 387 /**
 388  * drm_vblank_get - get a reference count on vblank events
 389  * @dev: DRM device
 390  * @crtc: which CRTC to own
 391  *
 392  * Acquire a reference count on vblank events to avoid having them disabled
 393  * while in use.
 394  *
 395  * RETURNS
 396  * Zero on success, nonzero on failure.
 397  */
 398 int drm_vblank_get(struct drm_device *dev, int crtc)
 399 {
 400         unsigned long irqflags;
 401         int ret = 0;
 402
 403         spin_lock_irqsave(&dev->vbl_lock, irqflags);
 404         /* Going from 0->1 means we have to enable interrupts again */
 405         if (atomic_add_return(1, &dev->vblank_refcount[crtc]) == 1 &&
 406             !dev->vblank_enabled[crtc]) {
 407                 ret = dev->driver->enable_vblank(dev, crtc);
 408                 DRM_DEBUG("enabling vblank on crtc %d, ret: %d\n", crtc, ret);
 409                 if (ret)
 410                         atomic_dec(&dev->vblank_refcount[crtc]);
 411                 else {
 412                         dev->vblank_enabled[crtc] = 1;
 413                         drm_update_vblank_count(dev, crtc);
 414                 }
 415         }
 416         spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
 417
 418         return ret;
 419 }
 420 EXPORT_SYMBOL(drm_vblank_get);
 421
 422 /**
 423  * drm_vblank_put - give up ownership of vblank events
 424  * @dev: DRM device
 425  * @crtc: which counter to give up
 426  *
 427  * Release ownership of a given vblank counter, turning off interrupts
 428  * if possible.
 429  */
 430 void drm_vblank_put(struct drm_device *dev, int crtc)
 431 {
 432         BUG_ON (atomic_read (&dev->vblank_refcount[crtc]) == 0);
 433
 434         /* Last user schedules interrupt disable */
 435         if (atomic_dec_and_test(&dev->vblank_refcount[crtc]))
 436                 mod_timer(&dev->vblank_disable_timer, jiffies + 5*DRM_HZ);
 437 }
 438 EXPORT_SYMBOL(drm_vblank_put);
 439
 440 /**
 441  * drm_vblank_pre_modeset - account for vblanks across mode sets
 442  * @dev: DRM device
 443  * @crtc: CRTC in question
 444  * @post: post or pre mode set?
 445  *
 446  * Account for vblank events across mode setting events, which will likely
 447  * reset the hardware frame counter.
 448  */
 449 void drm_vblank_pre_modeset(struct drm_device *dev, int crtc)
 450 {
 451         /*
 452          * To avoid all the problems that might happen if interrupts
 453          * were enabled/disabled around or between these calls, we just
 454          * have the kernel take a reference on the CRTC (just once though
 455          * to avoid corrupting the count if multiple, mismatch calls occur),
 456          * so that interrupts remain enabled in the interim.
 457          */
 458         if (!dev->vblank_inmodeset[crtc]) {
 459                 dev->vblank_inmodeset[crtc] = 0x1;
 460                 if (drm_vblank_get(dev, crtc) == 0)
 461                         dev->vblank_inmodeset[crtc] |= 0x2;
 462         }
 463 }
 464 EXPORT_SYMBOL(drm_vblank_pre_modeset);
 465
 466 void drm_vblank_post_modeset(struct drm_device *dev, int crtc)
 467 {
 468         unsigned long irqflags;
 469
 470         if (dev->vblank_inmodeset[crtc]) {
 471                 spin_lock_irqsave(&dev->vbl_lock, irqflags);
 472                 dev->vblank_disable_allowed = 1;
 473                 spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
 474
 475                 if (dev->vblank_inmodeset[crtc] & 0x2)
 476                         drm_vblank_put(dev, crtc);
 477
 478                 dev->vblank_inmodeset[crtc] = 0;
 479         }
 480 }
 481 EXPORT_SYMBOL(drm_vblank_post_modeset);
 482
 483 /**
 484  * drm_modeset_ctl - handle vblank event counter changes across mode switch
 485  * @DRM_IOCTL_ARGS: standard ioctl arguments
 486  *
 487  * Applications should call the %_DRM_PRE_MODESET and %_DRM_POST_MODESET
 488  * ioctls around modesetting so that any lost vblank events are accounted for.
 489  *
 490  * Generally the counter will reset across mode sets.  If interrupts are
 491  * enabled around this call, we don't have to do anything since the counter
 492  * will have already been incremented.
 493  */
 494 int drm_modeset_ctl(struct drm_device *dev, void *data,
 495                     struct drm_file *file_priv)
 496 {
 497         struct drm_modeset_ctl *modeset = data;
 498         int crtc, ret = 0;
 499
 500         /* If drm_vblank_init() hasn't been called yet, just no-op */
 501         if (!dev->num_crtcs)
 502                 goto out;
 503
 504         crtc = modeset->crtc;
 505         if (crtc >= dev->num_crtcs) {
 506                 ret = -EINVAL;
 507                 goto out;
 508         }
 509
 510         switch (modeset->cmd) {
 511         case _DRM_PRE_MODESET:
 512                 drm_vblank_pre_modeset(dev, crtc);
 513                 break;
 514         case _DRM_POST_MODESET:
 515                 drm_vblank_post_modeset(dev, crtc);
 516                 break;
 517         default:
 518                 ret = -EINVAL;
 519                 break;
 520         }
 521
 522 out:
 523         return ret;
 524 }
 525
 526 static int drm_queue_vblank_event(struct drm_device *dev, int pipe,
 527                                   union drm_wait_vblank *vblwait,
 528                                   struct drm_file *file_priv)
 529 {
 530         struct drm_pending_vblank_event *e;
 531         struct timeval now;
 532         unsigned long flags;
 533         unsigned int seq;
 534
 535         e = kzalloc(sizeof *e, GFP_KERNEL);
 536         if (e == NULL)
 537                 return -ENOMEM;
 538
 539         e->pipe = pipe;
 540         e->event.base.type = DRM_EVENT_VBLANK;
 541         e->event.base.length = sizeof e->event;
 542         e->event.user_data = vblwait->request.signal;
 543         e->base.event = &e->event.base;
 544         e->base.file_priv = file_priv;
 545         e->base.destroy = (void (*) (struct drm_pending_event *)) kfree;
 546
 547         do_gettimeofday(&now);
 548         spin_lock_irqsave(&dev->event_lock, flags);
 549
 550         if (file_priv->event_space < sizeof e->event) {
 551                 spin_unlock_irqrestore(&dev->event_lock, flags);
 552                 kfree(e);
 553                 return -ENOMEM;
 554         }
 555
 556         file_priv->event_space -= sizeof e->event;
 557         seq = drm_vblank_count(dev, pipe);
 558         if ((vblwait->request.type & _DRM_VBLANK_NEXTONMISS) &&
 559             (seq - vblwait->request.sequence) <= (1 << 23)) {
 560                 vblwait->request.sequence = seq + 1;
 561                 vblwait->reply.sequence = vblwait->request.sequence;
 562         }
 563
 564         DRM_DEBUG("event on vblank count %d, current %d, crtc %d\n",
 565                   vblwait->request.sequence, seq, pipe);
 566
 567         e->event.sequence = vblwait->request.sequence;
 568         if ((seq - vblwait->request.sequence) <= (1 << 23)) {
 569                 e->event.tv_sec = now.tv_sec;
 570                 e->event.tv_usec = now.tv_usec;
 571                 drm_vblank_put(dev, e->pipe);
 572                 list_add_tail(&e->base.link, &e->base.file_priv->event_list);
 573                 wake_up_interruptible(&e->base.file_priv->event_wait);
 574         } else {
 575                 list_add_tail(&e->base.link, &dev->vblank_event_list);
 576         }
 577
 578         spin_unlock_irqrestore(&dev->event_lock, flags);
 579
 580         return 0;
 581 }
 582
 583 /**
 584  * Wait for VBLANK.
 585  *
 586  * \param inode device inode.
 587  * \param file_priv DRM file private.
 588  * \param cmd command.
 589  * \param data user argument, pointing to a drm_wait_vblank structure.
 590  * \return zero on success or a negative number on failure.
 591  *
 592  * This function enables the vblank interrupt on the pipe requested, then
 593  * sleeps waiting for the requested sequence number to occur, and drops
 594  * the vblank interrupt refcount afterwards. (vblank irq disable follows that
 595  * after a timeout with no further vblank waits scheduled).
 596  */
 597 int drm_wait_vblank(struct drm_device *dev, void *data,
 598                     struct drm_file *file_priv)
 599 {
 600         union drm_wait_vblank *vblwait = data;
 601         int ret = 0;
 602         unsigned int flags, seq, crtc;
 603
 604         if ((!dev->pdev->irq) || (!dev->irq_enabled))
 605                 return -EINVAL;
 606
 607         if (vblwait->request.type & _DRM_VBLANK_SIGNAL)
 608                 return -EINVAL;
 609
 610         if (vblwait->request.type &
 611             ~(_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK)) {
 612                 DRM_ERROR("Unsupported type value 0x%x, supported mask 0x%x\n",
 613                           vblwait->request.type,
 614                           (_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK));
 615                 return -EINVAL;
 616         }
 617
 618         flags = vblwait->request.type & _DRM_VBLANK_FLAGS_MASK;
 619         crtc = flags & _DRM_VBLANK_SECONDARY ? 1 : 0;
 620
 621         if (crtc >= dev->num_crtcs)
 622                 return -EINVAL;
 623
 624         ret = drm_vblank_get(dev, crtc);
 625         if (ret) {
 626                 DRM_DEBUG("failed to acquire vblank counter, %d\n", ret);
 627                 return ret;
 628         }
 629         seq = drm_vblank_count(dev, crtc);
 630
 631         switch (vblwait->request.type & _DRM_VBLANK_TYPES_MASK) {
 632         case _DRM_VBLANK_RELATIVE:
 633                 vblwait->request.sequence += seq;
 634                 vblwait->request.type &= ~_DRM_VBLANK_RELATIVE;
 635         case _DRM_VBLANK_ABSOLUTE:
 636                 break;
 637         default:
 638                 ret = -EINVAL;
 639                 goto done;
 640         }
 641
 642         if (flags & _DRM_VBLANK_EVENT)
 643                 return drm_queue_vblank_event(dev, crtc, vblwait, file_priv);
 644
 645         if ((flags & _DRM_VBLANK_NEXTONMISS) &&
 646             (seq - vblwait->request.sequence) <= (1<<23)) {
 647                 vblwait->request.sequence = seq + 1;
 648         }
 649
 650         DRM_DEBUG("waiting on vblank count %d, crtc %d\n",
 651                   vblwait->request.sequence, crtc);
 652         dev->last_vblank_wait[crtc] = vblwait->request.sequence;
 653         DRM_WAIT_ON(ret, dev->vbl_queue[crtc], 3 * DRM_HZ,
 654                     (((drm_vblank_count(dev, crtc) -
 655                        vblwait->request.sequence) <= (1 << 23)) ||
 656                      !dev->irq_enabled));
 657
 658         if (ret != -EINTR) {
 659                 struct timeval now;
 660
 661                 do_gettimeofday(&now);
 662
 663                 vblwait->reply.tval_sec = now.tv_sec;
 664                 vblwait->reply.tval_usec = now.tv_usec;
 665                 vblwait->reply.sequence = drm_vblank_count(dev, crtc);
 666                 DRM_DEBUG("returning %d to client\n",
 667                           vblwait->reply.sequence);
 668         } else {
 669                 DRM_DEBUG("vblank wait interrupted by signal\n");
 670         }
 671
 672 done:
 673         drm_vblank_put(dev, crtc);
 674         return ret;
 675 }
 676
 677 void drm_handle_vblank_events(struct drm_device *dev, int crtc)
 678 {
 679         struct drm_pending_vblank_event *e, *t;
 680         struct timeval now;
 681         unsigned long flags;
 682         unsigned int seq;
 683
 684         do_gettimeofday(&now);
 685         seq = drm_vblank_count(dev, crtc);
 686
 687         spin_lock_irqsave(&dev->event_lock, flags);
 688
 689         list_for_each_entry_safe(e, t, &dev->vblank_event_list, base.link) {
 690                 if (e->pipe != crtc)
 691                         continue;
 692                 if ((seq - e->event.sequence) > (1<<23))
 693                         continue;
 694
 695                 DRM_DEBUG("vblank event on %d, current %d\n",
 696                           e->event.sequence, seq);
 697
 698                 e->event.sequence = seq;
 699                 e->event.tv_sec = now.tv_sec;
 700                 e->event.tv_usec = now.tv_usec;
 701                 drm_vblank_put(dev, e->pipe);
 702                 list_move_tail(&e->base.link, &e->base.file_priv->event_list);
 703                 wake_up_interruptible(&e->base.file_priv->event_wait);
 704         }
 705
 706         spin_unlock_irqrestore(&dev->event_lock, flags);
 707 }
 708
 709 /**
 710  * drm_handle_vblank - handle a vblank event
 711  * @dev: DRM device
 712  * @crtc: where this event occurred
 713  *
 714  * Drivers should call this routine in their vblank interrupt handlers to
 715  * update the vblank counter and send any signals that may be pending.
 716  */
 717 void drm_handle_vblank(struct drm_device *dev, int crtc)
 718 {
 719         if (!dev->num_crtcs)
 720                 return;
 721
 722         atomic_inc(&dev->_vblank_count[crtc]);
 723         DRM_WAKEUP(&dev->vbl_queue[crtc]);
 724         drm_handle_vblank_events(dev, crtc);
 725 }
 726 EXPORT_SYMBOL(drm_handle_vblank);