sys/dev/drm/drm_irq.c

   1 /*-
   2  * Copyright 2003 Eric Anholt
   3  * All Rights Reserved.
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a
   6  * copy of this software and associated documentation files (the "Software"),
   7  * to deal in the Software without restriction, including without limitation
   8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   9  * and/or sell copies of the Software, and to permit persons to whom the
  10  * Software is furnished to do so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice (including the next
  13  * paragraph) shall be included in all copies or substantial portions of the
  14  * Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  19  * ERIC ANHOLT BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
  20  * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  21  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  22  *
  23  * Authors:
  24  *    Eric Anholt <anholt@FreeBSD.org>
  25  *
  26  */
  27
  28 /** @file drm_irq.c
  29  * Support code for handling setup/teardown of interrupt handlers and
  30  * handing interrupt handlers off to the drivers.
  31  */
  32
  33 #include "dev/drm/drmP.h"
  34 #include "dev/drm/drm.h"
  35
  36 int drm_irq_by_busid(struct drm_device *dev, void *data,
  37                      struct drm_file *file_priv)
  38 {
  39         struct drm_irq_busid *irq = data;
  40
  41         if ((irq->busnum >> 8) != dev->pci_domain ||
  42             (irq->busnum & 0xff) != dev->pci_bus ||
  43             irq->devnum != dev->pci_slot ||
  44             irq->funcnum != dev->pci_func)
  45                 return EINVAL;
  46
  47         irq->irq = dev->irq;
  48
  49         DRM_DEBUG("%d:%d:%d => IRQ %d\n",
  50             irq->busnum, irq->devnum, irq->funcnum, irq->irq);
  51
  52         return 0;
  53 }
  54
  55 static void vblank_disable_fn(void *arg)
  56 {
  57         struct drm_device *dev = (struct drm_device *)arg;
  58         int i;
  59
  60         DRM_SPINLOCK(&dev->vbl_lock);
  61
  62         if (callout_pending(&dev->vblank_disable_timer)) {
  63                 /* callout was reset */
  64                 DRM_SPINUNLOCK(&dev->vbl_lock);
  65                 return;
  66         }
  67         if (!callout_active(&dev->vblank_disable_timer)) {
  68                 /* callout was stopped */
  69                 DRM_SPINUNLOCK(&dev->vbl_lock);
  70                 return;
  71         }
  72         callout_deactivate(&dev->vblank_disable_timer);
  73
  74         DRM_DEBUG("vblank_disable: %s\n", dev->vblank_disable_allowed ?
  75                 "allowed" : "denied");
  76         if (!dev->vblank_disable_allowed) {
  77                 DRM_SPINUNLOCK(&dev->vbl_lock);
  78                 return;
  79         }
  80
  81         for (i = 0; i < dev->num_crtcs; i++) {
  82                 if (dev->vblank[i].refcount == 0 &&
  83                     dev->vblank[i].enabled && !dev->vblank[i].inmodeset) {
  84                         DRM_DEBUG("disabling vblank on crtc %d\n", i);
  85                         dev->vblank[i].last =
  86                             dev->driver->get_vblank_counter(dev, i);
  87                         dev->driver->disable_vblank(dev, i);
  88                         dev->vblank[i].enabled = 0;
  89                 }
  90         }
  91         DRM_SPINUNLOCK(&dev->vbl_lock);
  92 }
  93
  94 void drm_vblank_cleanup(struct drm_device *dev)
  95 {
  96         /* Bail if the driver didn't call drm_vblank_init() */
  97         if (dev->num_crtcs == 0)
  98                 return;
  99
 100         DRM_SPINLOCK(&dev->vbl_lock);
 101         callout_stop(&dev->vblank_disable_timer);
 102         DRM_SPINUNLOCK(&dev->vbl_lock);
 103
 104         vblank_disable_fn((void *)dev);
 105
 106         free(dev->vblank, DRM_MEM_DRIVER);
 107
 108         dev->num_crtcs = 0;
 109 }
 110
 111 int drm_vblank_init(struct drm_device *dev, int num_crtcs)
 112 {
 113         int i, ret = ENOMEM;
 114
 115         callout_init(&dev->vblank_disable_timer);
 116         dev->num_crtcs = num_crtcs;
 117
 118         dev->vblank = malloc(sizeof(struct drm_vblank_info) * num_crtcs,
 119             DRM_MEM_DRIVER, M_NOWAIT | M_ZERO);
 120         if (!dev->vblank)
 121             goto err;
 122
 123         DRM_DEBUG("\n");
 124
 125         /* Zero per-crtc vblank stuff */
 126         DRM_SPINLOCK(&dev->vbl_lock);
 127         for (i = 0; i < num_crtcs; i++) {
 128                 DRM_INIT_WAITQUEUE(&dev->vblank[i].queue);
 129                 dev->vblank[i].refcount = 0;
 130                 atomic_set_rel_32(&dev->vblank[i].count, 0);
 131         }
 132         dev->vblank_disable_allowed = 0;
 133         DRM_SPINUNLOCK(&dev->vbl_lock);
 134
 135         return 0;
 136
 137 err:
 138         drm_vblank_cleanup(dev);
 139         return ret;
 140 }
 141
 142 int drm_irq_install(struct drm_device *dev)
 143 {
 144         int crtc, retcode;
 145
 146         if (dev->irq == 0 || dev->dev_private == NULL)
 147                 return EINVAL;
 148
 149         DRM_DEBUG("irq=%d\n", dev->irq);
 150
 151         DRM_LOCK();
 152         if (dev->irq_enabled) {
 153                 DRM_UNLOCK();
 154                 return EBUSY;
 155         }
 156         dev->irq_enabled = 1;
 157
 158         dev->context_flag = 0;
 159
 160         /* Before installing handler */
 161         dev->driver->irq_preinstall(dev);
 162         DRM_UNLOCK();
 163
 164         /* Install handler */
 165         retcode = bus_setup_intr(dev->device, dev->irqr, INTR_MPSAFE,
 166                                  dev->driver->irq_handler, dev, &dev->irqh,
 167                                  &dev->irq_lock);
 168         if (retcode != 0)
 169                 goto err;
 170
 171         /* After installing handler */
 172         DRM_LOCK();
 173         dev->driver->irq_postinstall(dev);
 174         DRM_UNLOCK();
 175         if (dev->driver->enable_vblank) {
 176                 DRM_SPINLOCK(&dev->vbl_lock);
 177                 for( crtc = 0 ; crtc < dev->num_crtcs ; crtc++) {
 178                         if (dev->driver->enable_vblank(dev, crtc) == 0) {
 179                                 dev->vblank[crtc].enabled = 1;
 180                         }
 181                 }
 182                 callout_reset(&dev->vblank_disable_timer, 5 * DRM_HZ,
 183                     (timeout_t *)vblank_disable_fn, (void *)dev);
 184                 DRM_SPINUNLOCK(&dev->vbl_lock);
 185         }
 186
 187         return 0;
 188 err:
 189         DRM_LOCK();
 190         dev->irq_enabled = 0;
 191         DRM_UNLOCK();
 192
 193         return retcode;
 194 }
 195
 196 int drm_irq_uninstall(struct drm_device *dev)
 197 {
 198         int crtc;
 199
 200         if (!dev->irq_enabled)
 201                 return EINVAL;
 202
 203         dev->irq_enabled = 0;
 204
 205         /*
 206         * Wake up any waiters so they don't hang.
 207         */
 208         DRM_SPINLOCK(&dev->vbl_lock);
 209         for (crtc = 0; crtc < dev->num_crtcs; crtc++) {
 210                 if (dev->vblank[crtc].enabled) {
 211                         DRM_WAKEUP(&dev->vblank[crtc].queue);
 212                         dev->vblank[crtc].last =
 213                             dev->driver->get_vblank_counter(dev, crtc);
 214                         dev->vblank[crtc].enabled = 0;
 215                 }
 216         }
 217         DRM_SPINUNLOCK(&dev->vbl_lock);
 218
 219         DRM_DEBUG("irq=%d\n", dev->irq);
 220
 221         dev->driver->irq_uninstall(dev);
 222
 223         DRM_UNLOCK();
 224         bus_teardown_intr(dev->device, dev->irqr, dev->irqh);
 225         DRM_LOCK();
 226
 227         return 0;
 228 }
 229
 230 int drm_control(struct drm_device *dev, void *data, struct drm_file *file_priv)
 231 {
 232         struct drm_control *ctl = data;
 233         int err;
 234
 235         switch (ctl->func) {
 236         case DRM_INST_HANDLER:
 237                 /* Handle drivers whose DRM used to require IRQ setup but the
 238                  * no longer does.
 239                  */
 240                 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
 241                         return 0;
 242                 if (dev->if_version < DRM_IF_VERSION(1, 2) &&
 243                     ctl->irq != dev->irq)
 244                         return EINVAL;
 245                 return drm_irq_install(dev);
 246         case DRM_UNINST_HANDLER:
 247                 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
 248                         return 0;
 249                 DRM_LOCK();
 250                 err = drm_irq_uninstall(dev);
 251                 DRM_UNLOCK();
 252                 return err;
 253         default:
 254                 return EINVAL;
 255         }
 256 }
 257
 258 u32 drm_vblank_count(struct drm_device *dev, int crtc)
 259 {
 260         return atomic_load_acq_32(&dev->vblank[crtc].count);
 261 }
 262
 263 static void drm_update_vblank_count(struct drm_device *dev, int crtc)
 264 {
 265         u32 cur_vblank, diff;
 266
 267         /*
 268          * Interrupts were disabled prior to this call, so deal with counter
 269          * wrap if needed.
 270          * NOTE!  It's possible we lost a full dev->max_vblank_count events
 271          * here if the register is small or we had vblank interrupts off for
 272          * a long time.
 273          */
 274         cur_vblank = dev->driver->get_vblank_counter(dev, crtc);
 275         diff = cur_vblank - dev->vblank[crtc].last;
 276         if (cur_vblank < dev->vblank[crtc].last) {
 277                 diff += dev->max_vblank_count;
 278
 279                 DRM_DEBUG("vblank[%d].last=0x%x, cur_vblank=0x%x => diff=0x%x\n",
 280                     crtc, dev->vblank[crtc].last, cur_vblank, diff);
 281         }
 282
 283         DRM_DEBUG("enabling vblank interrupts on crtc %d, missed %d\n",
 284             crtc, diff);
 285
 286         atomic_add_rel_32(&dev->vblank[crtc].count, diff);
 287 }
 288
 289 int drm_vblank_get(struct drm_device *dev, int crtc)
 290 {
 291         int ret = 0;
 292
 293         /* Make sure that we are called with the lock held */
 294         KKASSERT(lockstatus(&dev->vbl_lock, curthread) != 0);
 295
 296         /* Going from 0->1 means we have to enable interrupts again */
 297         if (++dev->vblank[crtc].refcount == 1 &&
 298             !dev->vblank[crtc].enabled) {
 299                 ret = dev->driver->enable_vblank(dev, crtc);
 300                 DRM_DEBUG("enabling vblank on crtc %d, ret: %d\n", crtc, ret);
 301                 if (ret)
 302                         --dev->vblank[crtc].refcount;
 303                 else {
 304                         dev->vblank[crtc].enabled = 1;
 305                         drm_update_vblank_count(dev, crtc);
 306                 }
 307         }
 308
 309         if (dev->vblank[crtc].enabled)
 310                 dev->vblank[crtc].last =
 311                     dev->driver->get_vblank_counter(dev, crtc);
 312
 313         return ret;
 314 }
 315
 316 void drm_vblank_put(struct drm_device *dev, int crtc)
 317 {
 318         /* Make sure that we are called with the lock held */
 319         KKASSERT(lockstatus(&dev->vbl_lock, curthread) != 0);
 320
 321         KASSERT(dev->vblank[crtc].refcount > 0,
 322             ("invalid refcount"));
 323
 324         /* Last user schedules interrupt disable */
 325         if (--dev->vblank[crtc].refcount == 0)
 326             callout_reset(&dev->vblank_disable_timer, 5 * DRM_HZ,
 327                 (timeout_t *)vblank_disable_fn, (void *)dev);
 328 }
 329
 330 int drm_modeset_ctl(struct drm_device *dev, void *data,
 331                     struct drm_file *file_priv)
 332 {
 333         struct drm_modeset_ctl *modeset = data;
 334         int crtc, ret = 0;
 335
 336         /* If drm_vblank_init() hasn't been called yet, just no-op */
 337         if (!dev->num_crtcs)
 338                 goto out;
 339
 340         crtc = modeset->crtc;
 341         if (crtc >= dev->num_crtcs) {
 342                 ret = EINVAL;
 343                 goto out;
 344         }
 345
 346         /*
 347          * To avoid all the problems that might happen if interrupts
 348          * were enabled/disabled around or between these calls, we just
 349          * have the kernel take a reference on the CRTC (just once though
 350          * to avoid corrupting the count if multiple, mismatch calls occur),
 351          * so that interrupts remain enabled in the interim.
 352          */
 353         switch (modeset->cmd) {
 354         case _DRM_PRE_MODESET:
 355                 DRM_DEBUG("pre-modeset, crtc %d\n", crtc);
 356                 DRM_SPINLOCK(&dev->vbl_lock);
 357                 if (!dev->vblank[crtc].inmodeset) {
 358                         dev->vblank[crtc].inmodeset = 0x1;
 359                         if (drm_vblank_get(dev, crtc) == 0)
 360                                 dev->vblank[crtc].inmodeset |= 0x2;
 361                 }
 362                 DRM_SPINUNLOCK(&dev->vbl_lock);
 363                 break;
 364         case _DRM_POST_MODESET:
 365                 DRM_DEBUG("post-modeset, crtc %d\n", crtc);
 366                 DRM_SPINLOCK(&dev->vbl_lock);
 367                 if (dev->vblank[crtc].inmodeset) {
 368                         if (dev->vblank[crtc].inmodeset & 0x2)
 369                                 drm_vblank_put(dev, crtc);
 370                         dev->vblank[crtc].inmodeset = 0;
 371                 }
 372                 dev->vblank_disable_allowed = 1;
 373                 DRM_SPINUNLOCK(&dev->vbl_lock);
 374                 break;
 375         default:
 376                 ret = EINVAL;
 377                 break;
 378         }
 379
 380 out:
 381         return ret;
 382 }
 383
 384 int drm_wait_vblank(struct drm_device *dev, void *data, struct drm_file *file_priv)
 385 {
 386         union drm_wait_vblank *vblwait = data;
 387         unsigned int flags, seq, crtc;
 388         int ret = 0;
 389
 390         if (!dev->irq_enabled)
 391                 return EINVAL;
 392
 393         if (vblwait->request.type &
 394             ~(_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK)) {
 395                 DRM_ERROR("Unsupported type value 0x%x, supported mask 0x%x\n",
 396                     vblwait->request.type,
 397                     (_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK));
 398                 return EINVAL;
 399         }
 400
 401         flags = vblwait->request.type & _DRM_VBLANK_FLAGS_MASK;
 402         crtc = flags & _DRM_VBLANK_SECONDARY ? 1 : 0;
 403
 404         if (crtc >= dev->num_crtcs)
 405                 return EINVAL;
 406
 407         DRM_SPINLOCK(&dev->vbl_lock);
 408         ret = drm_vblank_get(dev, crtc);
 409         DRM_SPINUNLOCK(&dev->vbl_lock);
 410         if (ret) {
 411                 DRM_ERROR("failed to acquire vblank counter, %d\n", ret);
 412                 return ret;
 413         }
 414         seq = drm_vblank_count(dev, crtc);
 415
 416         switch (vblwait->request.type & _DRM_VBLANK_TYPES_MASK) {
 417         case _DRM_VBLANK_RELATIVE:
 418                 vblwait->request.sequence += seq;
 419                 vblwait->request.type &= ~_DRM_VBLANK_RELATIVE;
 420         case _DRM_VBLANK_ABSOLUTE:
 421                 break;
 422         default:
 423                 ret = EINVAL;
 424                 goto done;
 425         }
 426
 427         if ((flags & _DRM_VBLANK_NEXTONMISS) &&
 428             (seq - vblwait->request.sequence) <= (1<<23)) {
 429                 vblwait->request.sequence = seq + 1;
 430         }
 431
 432         if (flags & _DRM_VBLANK_SIGNAL) {
 433                 /* There have never been any consumers */
 434                 ret = EINVAL;
 435         } else {
 436                 DRM_DEBUG("waiting on vblank count %d, crtc %d\n",
 437                     vblwait->request.sequence, crtc);
 438                 for ( ret = 0 ; !ret && !(((drm_vblank_count(dev, crtc) -
 439                     vblwait->request.sequence) <= (1 << 23)) ||
 440                     !dev->irq_enabled) ; ) {
 441                         lwkt_serialize_enter(&dev->irq_lock);
 442                         if (!(((drm_vblank_count(dev, crtc) -
 443                             vblwait->request.sequence) <= (1 << 23)) ||
 444                             !dev->irq_enabled))
 445                                 ret = zsleep(&dev->vblank[crtc].queue,
 446                                     &dev->irq_lock, PCATCH, "vblwtq",
 447                                     DRM_HZ);
 448                         lwkt_serialize_exit(&dev->irq_lock);
 449                 }
 450
 451                 if (ret != EINTR && ret != ERESTART) {
 452                         struct timeval now;
 453
 454                         microtime(&now);
 455                         vblwait->reply.tval_sec = now.tv_sec;
 456                         vblwait->reply.tval_usec = now.tv_usec;
 457                         vblwait->reply.sequence = drm_vblank_count(dev, crtc);
 458                         DRM_DEBUG("returning %d to client, irq_enabled %d\n",
 459                             vblwait->reply.sequence, dev->irq_enabled);
 460                 } else {
 461                         DRM_DEBUG("vblank wait interrupted by signal\n");
 462                 }
 463         }
 464
 465 done:
 466         DRM_SPINLOCK(&dev->vbl_lock);
 467         drm_vblank_put(dev, crtc);
 468         DRM_SPINUNLOCK(&dev->vbl_lock);
 469
 470         return ret;
 471 }
 472
 473 void drm_handle_vblank(struct drm_device *dev, int crtc)
 474 {
 475         atomic_add_rel_32(&dev->vblank[crtc].count, 1);
 476         DRM_WAKEUP(&dev->vblank[crtc].queue);
 477 }
 478