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 #include <linux/vgaarb.h>
  41 /**
  42  * Get interrupt from bus id.
  43  *
  44  * \param inode device inode.
  45  * \param file_priv DRM file private.
  46  * \param cmd command.
  47  * \param arg user argument, pointing to a drm_irq_busid structure.
  48  * \return zero on success or a negative number on failure.
  49  *
  50  * Finds the PCI device with the specified bus id and gets its IRQ number.
  51  * This IOCTL is deprecated, and will now return EINVAL for any busid not equal
  52  * to that of the device that this DRM instance attached to.
  53  */
  54 int drm_irq_by_busid(struct drm_device *dev, void *data,
  55                      struct drm_file *file_priv)
  56 {
  57         struct drm_irq_busid *p = data;
  58
  59         if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
  60                 return -EINVAL;
  61
  62         if ((p->busnum >> 8) != drm_get_pci_domain(dev) ||
  63             (p->busnum & 0xff) != dev->pdev->bus->number ||
  64             p->devnum != PCI_SLOT(dev->pdev->devfn) || p->funcnum != PCI_FUNC(dev->pdev->devfn))
  65                 return -EINVAL;
  66
  67         p->irq = dev->pdev->irq;
  68
  69         DRM_DEBUG("%d:%d:%d => IRQ %d\n", p->busnum, p->devnum, p->funcnum,
  70                   p->irq);
  71
  72         return 0;
  73 }
  74
  75 static void vblank_disable_fn(unsigned long arg)
  76 {
  77         struct drm_device *dev = (struct drm_device *)arg;
  78         unsigned long irqflags;
  79         int i;
  80
  81         if (!dev->vblank_disable_allowed)
  82                 return;
  83
  84         for (i = 0; i < dev->num_crtcs; i++) {
  85                 spin_lock_irqsave(&dev->vbl_lock, irqflags);
  86                 if (atomic_read(&dev->vblank_refcount[i]) == 0 &&
  87                     dev->vblank_enabled[i]) {
  88                         DRM_DEBUG("disabling vblank on crtc %d\n", i);
  89                         dev->last_vblank[i] =
  90                                 dev->driver->get_vblank_counter(dev, i);
  91                         dev->driver->disable_vblank(dev, i);
  92                         dev->vblank_enabled[i] = 0;
  93                 }
  94                 spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
  95         }
  96 }
  97
  98 void drm_vblank_cleanup(struct drm_device *dev)
  99 {
 100         /* Bail if the driver didn't call drm_vblank_init() */
 101         if (dev->num_crtcs == 0)
 102                 return;
 103
 104         del_timer(&dev->vblank_disable_timer);
 105
 106         vblank_disable_fn((unsigned long)dev);
 107
 108         kfree(dev->vbl_queue);
 109         kfree(dev->_vblank_count);
 110         kfree(dev->vblank_refcount);
 111         kfree(dev->vblank_enabled);
 112         kfree(dev->last_vblank);
 113         kfree(dev->last_vblank_wait);
 114         kfree(dev->vblank_inmodeset);
 115
 116         dev->num_crtcs = 0;
 117 }
 118
 119 int drm_vblank_init(struct drm_device *dev, int num_crtcs)
 120 {
 121         int i, ret = -ENOMEM;
 122
 123         setup_timer(&dev->vblank_disable_timer, vblank_disable_fn,
 124                     (unsigned long)dev);
 125         spin_lock_init(&dev->vbl_lock);
 126         dev->num_crtcs = num_crtcs;
 127
 128         dev->vbl_queue = kmalloc(sizeof(wait_queue_head_t) * num_crtcs,
 129                                  GFP_KERNEL);
 130         if (!dev->vbl_queue)
 131                 goto err;
 132
 133         dev->_vblank_count = kmalloc(sizeof(atomic_t) * num_crtcs, GFP_KERNEL);
 134         if (!dev->_vblank_count)
 135                 goto err;
 136
 137         dev->vblank_refcount = kmalloc(sizeof(atomic_t) * num_crtcs,
 138                                        GFP_KERNEL);
 139         if (!dev->vblank_refcount)
 140                 goto err;
 141
 142         dev->vblank_enabled = kcalloc(num_crtcs, sizeof(int), GFP_KERNEL);
 143         if (!dev->vblank_enabled)
 144                 goto err;
 145
 146         dev->last_vblank = kcalloc(num_crtcs, sizeof(u32), GFP_KERNEL);
 147         if (!dev->last_vblank)
 148                 goto err;
 149
 150         dev->last_vblank_wait = kcalloc(num_crtcs, sizeof(u32), GFP_KERNEL);
 151         if (!dev->last_vblank_wait)
 152                 goto err;
 153
 154         dev->vblank_inmodeset = kcalloc(num_crtcs, sizeof(int), GFP_KERNEL);
 155         if (!dev->vblank_inmodeset)
 156                 goto err;
 157
 158         /* Zero per-crtc vblank stuff */
 159         for (i = 0; i < num_crtcs; i++) {
 160                 init_waitqueue_head(&dev->vbl_queue[i]);
 161                 atomic_set(&dev->_vblank_count[i], 0);
 162                 atomic_set(&dev->vblank_refcount[i], 0);
 163         }
 164
 165         dev->vblank_disable_allowed = 0;
 166
 167         return 0;
 168
 169 err:
 170         drm_vblank_cleanup(dev);
 171         return ret;
 172 }
 173 EXPORT_SYMBOL(drm_vblank_init);
 174
 175 static void drm_irq_vgaarb_nokms(void *cookie, bool state)
 176 {
 177         struct drm_device *dev = cookie;
 178
 179         if (dev->driver->vgaarb_irq) {
 180                 dev->driver->vgaarb_irq(dev, state);
 181                 return;
 182         }
 183
 184         if (!dev->irq_enabled)
 185                 return;
 186
 187         if (state)
 188                 dev->driver->irq_uninstall(dev);
 189         else {
 190                 dev->driver->irq_preinstall(dev);
 191                 dev->driver->irq_postinstall(dev);
 192         }
 193 }
 194
 195 /**
 196  * Install IRQ handler.
 197  *
 198  * \param dev DRM device.
 199  *
 200  * Initializes the IRQ related data. Installs the handler, calling the driver
 201  * \c drm_driver_irq_preinstall() and \c drm_driver_irq_postinstall() functions
 202  * before and after the installation.
 203  */
 204 int drm_irq_install(struct drm_device *dev)
 205 {
 206         int ret = 0;
 207         unsigned long sh_flags = 0;
 208         char *irqname;
 209
 210         if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
 211                 return -EINVAL;
 212
 213         if (dev->pdev->irq == 0)
 214                 return -EINVAL;
 215
 216         mutex_lock(&dev->struct_mutex);
 217
 218         /* Driver must have been initialized */
 219         if (!dev->dev_private) {
 220                 mutex_unlock(&dev->struct_mutex);
 221                 return -EINVAL;
 222         }
 223
 224         if (dev->irq_enabled) {
 225                 mutex_unlock(&dev->struct_mutex);
 226                 return -EBUSY;
 227         }
 228         dev->irq_enabled = 1;
 229         mutex_unlock(&dev->struct_mutex);
 230
 231         DRM_DEBUG("irq=%d\n", dev->pdev->irq);
 232
 233         /* Before installing handler */
 234         dev->driver->irq_preinstall(dev);
 235
 236         /* Install handler */
 237         if (drm_core_check_feature(dev, DRIVER_IRQ_SHARED))
 238                 sh_flags = IRQF_SHARED;
 239
 240         if (dev->devname)
 241                 irqname = dev->devname;
 242         else
 243                 irqname = dev->driver->name;
 244
 245         ret = request_irq(drm_dev_to_irq(dev), dev->driver->irq_handler,
 246                           sh_flags, irqname, dev);
 247
 248         if (ret < 0) {
 249                 mutex_lock(&dev->struct_mutex);
 250                 dev->irq_enabled = 0;
 251                 mutex_unlock(&dev->struct_mutex);
 252                 return ret;
 253         }
 254
 255         if (!drm_core_check_feature(dev, DRIVER_MODESET))
 256                 vga_client_register(dev->pdev, (void *)dev, drm_irq_vgaarb_nokms, NULL);
 257
 258         /* After installing handler */
 259         ret = dev->driver->irq_postinstall(dev);
 260         if (ret < 0) {
 261                 mutex_lock(&dev->struct_mutex);
 262                 dev->irq_enabled = 0;
 263                 mutex_unlock(&dev->struct_mutex);
 264         }
 265
 266         return ret;
 267 }
 268 EXPORT_SYMBOL(drm_irq_install);
 269
 270 /**
 271  * Uninstall the IRQ handler.
 272  *
 273  * \param dev DRM device.
 274  *
 275  * Calls the driver's \c drm_driver_irq_uninstall() function, and stops the irq.
 276  */
 277 int drm_irq_uninstall(struct drm_device * dev)
 278 {
 279         unsigned long irqflags;
 280         int irq_enabled, i;
 281
 282         if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
 283                 return -EINVAL;
 284
 285         mutex_lock(&dev->struct_mutex);
 286         irq_enabled = dev->irq_enabled;
 287         dev->irq_enabled = 0;
 288         mutex_unlock(&dev->struct_mutex);
 289
 290         /*
 291          * Wake up any waiters so they don't hang.
 292          */
 293         spin_lock_irqsave(&dev->vbl_lock, irqflags);
 294         for (i = 0; i < dev->num_crtcs; i++) {
 295                 DRM_WAKEUP(&dev->vbl_queue[i]);
 296                 dev->vblank_enabled[i] = 0;
 297                 dev->last_vblank[i] = dev->driver->get_vblank_counter(dev, i);
 298         }
 299         spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
 300
 301         if (!irq_enabled)
 302                 return -EINVAL;
 303
 304         DRM_DEBUG("irq=%d\n", dev->pdev->irq);
 305
 306         if (!drm_core_check_feature(dev, DRIVER_MODESET))
 307                 vga_client_register(dev->pdev, NULL, NULL, NULL);
 308
 309         dev->driver->irq_uninstall(dev);
 310
 311         free_irq(dev->pdev->irq, dev);
 312
 313         return 0;
 314 }
 315 EXPORT_SYMBOL(drm_irq_uninstall);
 316
 317 /**
 318  * IRQ control ioctl.
 319  *
 320  * \param inode device inode.
 321  * \param file_priv DRM file private.
 322  * \param cmd command.
 323  * \param arg user argument, pointing to a drm_control structure.
 324  * \return zero on success or a negative number on failure.
 325  *
 326  * Calls irq_install() or irq_uninstall() according to \p arg.
 327  */
 328 int drm_control(struct drm_device *dev, void *data,
 329                 struct drm_file *file_priv)
 330 {
 331         struct drm_control *ctl = data;
 332
 333         /* if we haven't irq we fallback for compatibility reasons - this used to be a separate function in drm_dma.h */
 334
 335
 336         switch (ctl->func) {
 337         case DRM_INST_HANDLER:
 338                 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
 339                         return 0;
 340                 if (drm_core_check_feature(dev, DRIVER_MODESET))
 341                         return 0;
 342                 if (dev->if_version < DRM_IF_VERSION(1, 2) &&
 343                     ctl->irq != dev->pdev->irq)
 344                         return -EINVAL;
 345                 return drm_irq_install(dev);
 346         case DRM_UNINST_HANDLER:
 347                 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
 348                         return 0;
 349                 if (drm_core_check_feature(dev, DRIVER_MODESET))
 350                         return 0;
 351                 return drm_irq_uninstall(dev);
 352         default:
 353                 return -EINVAL;
 354         }
 355 }
 356
 357 /**
 358  * drm_vblank_count - retrieve "cooked" vblank counter value
 359  * @dev: DRM device
 360  * @crtc: which counter to retrieve
 361  *
 362  * Fetches the "cooked" vblank count value that represents the number of
 363  * vblank events since the system was booted, including lost events due to
 364  * modesetting activity.
 365  */
 366 u32 drm_vblank_count(struct drm_device *dev, int crtc)
 367 {
 368         return atomic_read(&dev->_vblank_count[crtc]);
 369 }
 370 EXPORT_SYMBOL(drm_vblank_count);
 371
 372 /**
 373  * drm_update_vblank_count - update the master vblank counter
 374  * @dev: DRM device
 375  * @crtc: counter to update
 376  *
 377  * Call back into the driver to update the appropriate vblank counter
 378  * (specified by @crtc).  Deal with wraparound, if it occurred, and
 379  * update the last read value so we can deal with wraparound on the next
 380  * call if necessary.
 381  *
 382  * Only necessary when going from off->on, to account for frames we
 383  * didn't get an interrupt for.
 384  *
 385  * Note: caller must hold dev->vbl_lock since this reads & writes
 386  * device vblank fields.
 387  */
 388 static void drm_update_vblank_count(struct drm_device *dev, int crtc)
 389 {
 390         u32 cur_vblank, diff;
 391
 392         /*
 393          * Interrupts were disabled prior to this call, so deal with counter
 394          * wrap if needed.
 395          * NOTE!  It's possible we lost a full dev->max_vblank_count events
 396          * here if the register is small or we had vblank interrupts off for
 397          * a long time.
 398          */
 399         cur_vblank = dev->driver->get_vblank_counter(dev, crtc);
 400         diff = cur_vblank - dev->last_vblank[crtc];
 401         if (cur_vblank < dev->last_vblank[crtc]) {
 402                 diff += dev->max_vblank_count;
 403
 404                 DRM_DEBUG("last_vblank[%d]=0x%x, cur_vblank=0x%x => diff=0x%x\n",
 405                           crtc, dev->last_vblank[crtc], cur_vblank, diff);
 406         }
 407
 408         DRM_DEBUG("enabling vblank interrupts on crtc %d, missed %d\n",
 409                   crtc, diff);
 410
 411         atomic_add(diff, &dev->_vblank_count[crtc]);
 412 }
 413
 414 /**
 415  * drm_vblank_get - get a reference count on vblank events
 416  * @dev: DRM device
 417  * @crtc: which CRTC to own
 418  *
 419  * Acquire a reference count on vblank events to avoid having them disabled
 420  * while in use.
 421  *
 422  * RETURNS
 423  * Zero on success, nonzero on failure.
 424  */
 425 int drm_vblank_get(struct drm_device *dev, int crtc)
 426 {
 427         unsigned long irqflags;
 428         int ret = 0;
 429
 430         spin_lock_irqsave(&dev->vbl_lock, irqflags);
 431         /* Going from 0->1 means we have to enable interrupts again */
 432         if (atomic_add_return(1, &dev->vblank_refcount[crtc]) == 1) {
 433                 if (!dev->vblank_enabled[crtc]) {
 434                         ret = dev->driver->enable_vblank(dev, crtc);
 435                         DRM_DEBUG("enabling vblank on crtc %d, ret: %d\n", crtc, ret);
 436                         if (ret)
 437                                 atomic_dec(&dev->vblank_refcount[crtc]);
 438                         else {
 439                                 dev->vblank_enabled[crtc] = 1;
 440                                 drm_update_vblank_count(dev, crtc);
 441                         }
 442                 }
 443         } else {
 444                 if (!dev->vblank_enabled[crtc]) {
 445                         atomic_dec(&dev->vblank_refcount[crtc]);
 446                         ret = -EINVAL;
 447                 }
 448         }
 449         spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
 450
 451         return ret;
 452 }
 453 EXPORT_SYMBOL(drm_vblank_get);
 454
 455 /**
 456  * drm_vblank_put - give up ownership of vblank events
 457  * @dev: DRM device
 458  * @crtc: which counter to give up
 459  *
 460  * Release ownership of a given vblank counter, turning off interrupts
 461  * if possible.
 462  */
 463 void drm_vblank_put(struct drm_device *dev, int crtc)
 464 {
 465         BUG_ON (atomic_read (&dev->vblank_refcount[crtc]) == 0);
 466
 467         /* Last user schedules interrupt disable */
 468         if (atomic_dec_and_test(&dev->vblank_refcount[crtc]))
 469                 mod_timer(&dev->vblank_disable_timer, jiffies + 5*DRM_HZ);
 470 }
 471 EXPORT_SYMBOL(drm_vblank_put);
 472
 473 void drm_vblank_off(struct drm_device *dev, int crtc)
 474 {
 475         unsigned long irqflags;
 476
 477         spin_lock_irqsave(&dev->vbl_lock, irqflags);
 478         DRM_WAKEUP(&dev->vbl_queue[crtc]);
 479         dev->vblank_enabled[crtc] = 0;
 480         dev->last_vblank[crtc] = dev->driver->get_vblank_counter(dev, crtc);
 481         spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
 482 }
 483 EXPORT_SYMBOL(drm_vblank_off);
 484
 485 /**
 486  * drm_vblank_pre_modeset - account for vblanks across mode sets
 487  * @dev: DRM device
 488  * @crtc: CRTC in question
 489  * @post: post or pre mode set?
 490  *
 491  * Account for vblank events across mode setting events, which will likely
 492  * reset the hardware frame counter.
 493  */
 494 void drm_vblank_pre_modeset(struct drm_device *dev, int crtc)
 495 {
 496         /*
 497          * To avoid all the problems that might happen if interrupts
 498          * were enabled/disabled around or between these calls, we just
 499          * have the kernel take a reference on the CRTC (just once though
 500          * to avoid corrupting the count if multiple, mismatch calls occur),
 501          * so that interrupts remain enabled in the interim.
 502          */
 503         if (!dev->vblank_inmodeset[crtc]) {
 504                 dev->vblank_inmodeset[crtc] = 0x1;
 505                 if (drm_vblank_get(dev, crtc) == 0)
 506                         dev->vblank_inmodeset[crtc] |= 0x2;
 507         }
 508 }
 509 EXPORT_SYMBOL(drm_vblank_pre_modeset);
 510
 511 void drm_vblank_post_modeset(struct drm_device *dev, int crtc)
 512 {
 513         unsigned long irqflags;
 514
 515         if (dev->vblank_inmodeset[crtc]) {
 516                 spin_lock_irqsave(&dev->vbl_lock, irqflags);
 517                 dev->vblank_disable_allowed = 1;
 518                 spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
 519
 520                 if (dev->vblank_inmodeset[crtc] & 0x2)
 521                         drm_vblank_put(dev, crtc);
 522
 523                 dev->vblank_inmodeset[crtc] = 0;
 524         }
 525 }
 526 EXPORT_SYMBOL(drm_vblank_post_modeset);
 527
 528 /**
 529  * drm_modeset_ctl - handle vblank event counter changes across mode switch
 530  * @DRM_IOCTL_ARGS: standard ioctl arguments
 531  *
 532  * Applications should call the %_DRM_PRE_MODESET and %_DRM_POST_MODESET
 533  * ioctls around modesetting so that any lost vblank events are accounted for.
 534  *
 535  * Generally the counter will reset across mode sets.  If interrupts are
 536  * enabled around this call, we don't have to do anything since the counter
 537  * will have already been incremented.
 538  */
 539 int drm_modeset_ctl(struct drm_device *dev, void *data,
 540                     struct drm_file *file_priv)
 541 {
 542         struct drm_modeset_ctl *modeset = data;
 543         int crtc, ret = 0;
 544
 545         /* If drm_vblank_init() hasn't been called yet, just no-op */
 546         if (!dev->num_crtcs)
 547                 goto out;
 548
 549         crtc = modeset->crtc;
 550         if (crtc >= dev->num_crtcs) {
 551                 ret = -EINVAL;
 552                 goto out;
 553         }
 554
 555         switch (modeset->cmd) {
 556         case _DRM_PRE_MODESET:
 557                 drm_vblank_pre_modeset(dev, crtc);
 558                 break;
 559         case _DRM_POST_MODESET:
 560                 drm_vblank_post_modeset(dev, crtc);
 561                 break;
 562         default:
 563                 ret = -EINVAL;
 564                 break;
 565         }
 566
 567 out:
 568         return ret;
 569 }
 570
 571 static int drm_queue_vblank_event(struct drm_device *dev, int pipe,
 572                                   union drm_wait_vblank *vblwait,
 573                                   struct drm_file *file_priv)
 574 {
 575         struct drm_pending_vblank_event *e;
 576         struct timeval now;
 577         unsigned long flags;
 578         unsigned int seq;
 579
 580         e = kzalloc(sizeof *e, GFP_KERNEL);
 581         if (e == NULL)
 582                 return -ENOMEM;
 583
 584         e->pipe = pipe;
 585         e->event.base.type = DRM_EVENT_VBLANK;
 586         e->event.base.length = sizeof e->event;
 587         e->event.user_data = vblwait->request.signal;
 588         e->base.event = &e->event.base;
 589         e->base.file_priv = file_priv;
 590         e->base.destroy = (void (*) (struct drm_pending_event *)) kfree;
 591
 592         do_gettimeofday(&now);
 593         spin_lock_irqsave(&dev->event_lock, flags);
 594
 595         if (file_priv->event_space < sizeof e->event) {
 596                 spin_unlock_irqrestore(&dev->event_lock, flags);
 597                 kfree(e);
 598                 return -ENOMEM;
 599         }
 600
 601         file_priv->event_space -= sizeof e->event;
 602         seq = drm_vblank_count(dev, pipe);
 603         if ((vblwait->request.type & _DRM_VBLANK_NEXTONMISS) &&
 604             (seq - vblwait->request.sequence) <= (1 << 23)) {
 605                 vblwait->request.sequence = seq + 1;
 606                 vblwait->reply.sequence = vblwait->request.sequence;
 607         }
 608
 609         DRM_DEBUG("event on vblank count %d, current %d, crtc %d\n",
 610                   vblwait->request.sequence, seq, pipe);
 611
 612         e->event.sequence = vblwait->request.sequence;
 613         if ((seq - vblwait->request.sequence) <= (1 << 23)) {
 614                 e->event.tv_sec = now.tv_sec;
 615                 e->event.tv_usec = now.tv_usec;
 616                 drm_vblank_put(dev, e->pipe);
 617                 list_add_tail(&e->base.link, &e->base.file_priv->event_list);
 618                 wake_up_interruptible(&e->base.file_priv->event_wait);
 619         } else {
 620                 list_add_tail(&e->base.link, &dev->vblank_event_list);
 621         }
 622
 623         spin_unlock_irqrestore(&dev->event_lock, flags);
 624
 625         return 0;
 626 }
 627
 628 /**
 629  * Wait for VBLANK.
 630  *
 631  * \param inode device inode.
 632  * \param file_priv DRM file private.
 633  * \param cmd command.
 634  * \param data user argument, pointing to a drm_wait_vblank structure.
 635  * \return zero on success or a negative number on failure.
 636  *
 637  * This function enables the vblank interrupt on the pipe requested, then
 638  * sleeps waiting for the requested sequence number to occur, and drops
 639  * the vblank interrupt refcount afterwards. (vblank irq disable follows that
 640  * after a timeout with no further vblank waits scheduled).
 641  */
 642 int drm_wait_vblank(struct drm_device *dev, void *data,
 643                     struct drm_file *file_priv)
 644 {
 645         union drm_wait_vblank *vblwait = data;
 646         int ret = 0;
 647         unsigned int flags, seq, crtc;
 648
 649         if ((!dev->pdev->irq) || (!dev->irq_enabled))
 650                 return -EINVAL;
 651
 652         if (vblwait->request.type & _DRM_VBLANK_SIGNAL)
 653                 return -EINVAL;
 654
 655         if (vblwait->request.type &
 656             ~(_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK)) {
 657                 DRM_ERROR("Unsupported type value 0x%x, supported mask 0x%x\n",
 658                           vblwait->request.type,
 659                           (_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK));
 660                 return -EINVAL;
 661         }
 662
 663         flags = vblwait->request.type & _DRM_VBLANK_FLAGS_MASK;
 664         crtc = flags & _DRM_VBLANK_SECONDARY ? 1 : 0;
 665
 666         if (crtc >= dev->num_crtcs)
 667                 return -EINVAL;
 668
 669         ret = drm_vblank_get(dev, crtc);
 670         if (ret) {
 671                 DRM_DEBUG("failed to acquire vblank counter, %d\n", ret);
 672                 return ret;
 673         }
 674         seq = drm_vblank_count(dev, crtc);
 675
 676         switch (vblwait->request.type & _DRM_VBLANK_TYPES_MASK) {
 677         case _DRM_VBLANK_RELATIVE:
 678                 vblwait->request.sequence += seq;
 679                 vblwait->request.type &= ~_DRM_VBLANK_RELATIVE;
 680         case _DRM_VBLANK_ABSOLUTE:
 681                 break;
 682         default:
 683                 ret = -EINVAL;
 684                 goto done;
 685         }
 686
 687         if (flags & _DRM_VBLANK_EVENT)
 688                 return drm_queue_vblank_event(dev, crtc, vblwait, file_priv);
 689
 690         if ((flags & _DRM_VBLANK_NEXTONMISS) &&
 691             (seq - vblwait->request.sequence) <= (1<<23)) {
 692                 vblwait->request.sequence = seq + 1;
 693         }
 694
 695         DRM_DEBUG("waiting on vblank count %d, crtc %d\n",
 696                   vblwait->request.sequence, crtc);
 697         dev->last_vblank_wait[crtc] = vblwait->request.sequence;
 698         DRM_WAIT_ON(ret, dev->vbl_queue[crtc], 3 * DRM_HZ,
 699                     (((drm_vblank_count(dev, crtc) -
 700                        vblwait->request.sequence) <= (1 << 23)) ||
 701                      !dev->irq_enabled));
 702
 703         if (ret != -EINTR) {
 704                 struct timeval now;
 705
 706                 do_gettimeofday(&now);
 707
 708                 vblwait->reply.tval_sec = now.tv_sec;
 709                 vblwait->reply.tval_usec = now.tv_usec;
 710                 vblwait->reply.sequence = drm_vblank_count(dev, crtc);
 711                 DRM_DEBUG("returning %d to client\n",
 712                           vblwait->reply.sequence);
 713         } else {
 714                 DRM_DEBUG("vblank wait interrupted by signal\n");
 715         }
 716
 717 done:
 718         drm_vblank_put(dev, crtc);
 719         return ret;
 720 }
 721
 722 void drm_handle_vblank_events(struct drm_device *dev, int crtc)
 723 {
 724         struct drm_pending_vblank_event *e, *t;
 725         struct timeval now;
 726         unsigned long flags;
 727         unsigned int seq;
 728
 729         do_gettimeofday(&now);
 730         seq = drm_vblank_count(dev, crtc);
 731
 732         spin_lock_irqsave(&dev->event_lock, flags);
 733
 734         list_for_each_entry_safe(e, t, &dev->vblank_event_list, base.link) {
 735                 if (e->pipe != crtc)
 736                         continue;
 737                 if ((seq - e->event.sequence) > (1<<23))
 738                         continue;
 739
 740                 DRM_DEBUG("vblank event on %d, current %d\n",
 741                           e->event.sequence, seq);
 742
 743                 e->event.sequence = seq;
 744                 e->event.tv_sec = now.tv_sec;
 745                 e->event.tv_usec = now.tv_usec;
 746                 drm_vblank_put(dev, e->pipe);
 747                 list_move_tail(&e->base.link, &e->base.file_priv->event_list);
 748                 wake_up_interruptible(&e->base.file_priv->event_wait);
 749         }
 750
 751         spin_unlock_irqrestore(&dev->event_lock, flags);
 752 }
 753
 754 /**
 755  * drm_handle_vblank - handle a vblank event
 756  * @dev: DRM device
 757  * @crtc: where this event occurred
 758  *
 759  * Drivers should call this routine in their vblank interrupt handlers to
 760  * update the vblank counter and send any signals that may be pending.
 761  */
 762 void drm_handle_vblank(struct drm_device *dev, int crtc)
 763 {
 764         if (!dev->num_crtcs)
 765                 return;
 766
 767         atomic_inc(&dev->_vblank_count[crtc]);
 768         DRM_WAKEUP(&dev->vbl_queue[crtc]);
 769         drm_handle_vblank_events(dev, crtc);
 770 }
 771 EXPORT_SYMBOL(drm_handle_vblank);