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         if (callout_pending(&dev->vblank_disable_timer)) {
  61                 /* callout was reset */
  62                 return;
  63         }
  64         if (!callout_active(&dev->vblank_disable_timer)) {
  65                 /* callout was stopped */
  66                 return;
  67         }
  68         callout_deactivate(&dev->vblank_disable_timer);
  69
  70         DRM_DEBUG("vblank_disable: %s\n", dev->vblank_disable_allowed ?
  71                 "allowed" : "denied");
  72         if (!dev->vblank_disable_allowed)
  73                 return;
  74
  75         for (i = 0; i < dev->num_crtcs; i++) {
  76                 if (atomic_read(&dev->vblank[i].refcount) == 0 &&
  77                     dev->vblank[i].enabled && !dev->vblank[i].inmodeset) {
  78                         DRM_DEBUG("disabling vblank on crtc %d\n", i);
  79                         dev->vblank[i].last =
  80                             dev->driver->get_vblank_counter(dev, i);
  81                         dev->driver->disable_vblank(dev, i);
  82                         dev->vblank[i].enabled = 0;
  83                 }
  84         }
  85 }
  86
  87 void drm_vblank_cleanup(struct drm_device *dev)
  88 {
  89         /* Bail if the driver didn't call drm_vblank_init() */
  90         if (dev->num_crtcs == 0)
  91                 return;
  92
  93         DRM_SPINLOCK(&dev->vbl_lock);
  94         callout_stop(&dev->vblank_disable_timer);
  95         DRM_SPINUNLOCK(&dev->vbl_lock);
  96
  97         vblank_disable_fn((void *)dev);
  98
  99         free(dev->vblank, DRM_MEM_DRIVER);
 100
 101         dev->num_crtcs = 0;
 102 }
 103
 104 int drm_vblank_init(struct drm_device *dev, int num_crtcs)
 105 {
 106         int i, ret = ENOMEM;
 107
 108         callout_init(&dev->vblank_disable_timer);
 109         dev->num_crtcs = num_crtcs;
 110
 111         dev->vblank = malloc(sizeof(struct drm_vblank_info) * num_crtcs,
 112             DRM_MEM_DRIVER, M_NOWAIT | M_ZERO);
 113         if (!dev->vblank)
 114             goto err;
 115
 116         DRM_DEBUG("\n");
 117
 118         /* Zero per-crtc vblank stuff */
 119         for (i = 0; i < num_crtcs; i++) {
 120                 DRM_INIT_WAITQUEUE(&dev->vblank[i].queue);
 121                 atomic_set(&dev->vblank[i].count, 0);
 122                 atomic_set(&dev->vblank[i].refcount, 0);
 123         }
 124
 125         dev->vblank_disable_allowed = 0;
 126
 127         return 0;
 128
 129 err:
 130         drm_vblank_cleanup(dev);
 131         return ret;
 132 }
 133
 134 int drm_irq_install(struct drm_device *dev)
 135 {
 136         int crtc, retcode;
 137
 138         if (dev->irq == 0 || dev->dev_private == NULL)
 139                 return EINVAL;
 140
 141         DRM_DEBUG("irq=%d\n", dev->irq);
 142
 143         DRM_LOCK();
 144         if (dev->irq_enabled) {
 145                 DRM_UNLOCK();
 146                 return EBUSY;
 147         }
 148         dev->irq_enabled = 1;
 149
 150         dev->context_flag = 0;
 151
 152         /* Before installing handler */
 153         dev->driver->irq_preinstall(dev);
 154         DRM_UNLOCK();
 155
 156         /* Install handler */
 157         retcode = bus_setup_intr(dev->device, dev->irqr, INTR_MPSAFE,
 158                                  dev->driver->irq_handler, dev, &dev->irqh,
 159                                  &dev->irq_lock);
 160         if (retcode != 0)
 161                 goto err;
 162
 163         /* After installing handler */
 164         DRM_LOCK();
 165         dev->driver->irq_postinstall(dev);
 166         DRM_UNLOCK();
 167         if (dev->driver->enable_vblank) {
 168                 DRM_SPINLOCK(&dev->vbl_lock);
 169                 for( crtc = 0 ; crtc < dev->num_crtcs ; crtc++) {
 170                         if (dev->driver->enable_vblank(dev, crtc) == 0) {
 171                                 dev->vblank[crtc].enabled = 1;
 172                         }
 173                 }
 174                 callout_reset(&dev->vblank_disable_timer, 5 * DRM_HZ,
 175                     (timeout_t *)vblank_disable_fn, (void *)dev);
 176                 DRM_SPINUNLOCK(&dev->vbl_lock);
 177         }
 178
 179         return 0;
 180 err:
 181         DRM_LOCK();
 182         dev->irq_enabled = 0;
 183         DRM_UNLOCK();
 184
 185         return retcode;
 186 }
 187
 188 int drm_irq_uninstall(struct drm_device *dev)
 189 {
 190         int crtc;
 191
 192         if (!dev->irq_enabled)
 193                 return EINVAL;
 194
 195         dev->irq_enabled = 0;
 196
 197         /*
 198         * Wake up any waiters so they don't hang.
 199         */
 200         DRM_SPINLOCK(&dev->vbl_lock);
 201         for (crtc = 0; crtc < dev->num_crtcs; crtc++) {
 202                 if (dev->vblank[crtc].enabled) {
 203                         DRM_WAKEUP(&dev->vblank[crtc].queue);
 204                         dev->vblank[crtc].last =
 205                             dev->driver->get_vblank_counter(dev, crtc);
 206                         dev->vblank[crtc].enabled = 0;
 207                 }
 208         }
 209         DRM_SPINUNLOCK(&dev->vbl_lock);
 210
 211         DRM_DEBUG("irq=%d\n", dev->irq);
 212
 213         dev->driver->irq_uninstall(dev);
 214
 215         DRM_UNLOCK();
 216         bus_teardown_intr(dev->device, dev->irqr, dev->irqh);
 217         DRM_LOCK();
 218
 219         return 0;
 220 }
 221
 222 int drm_control(struct drm_device *dev, void *data, struct drm_file *file_priv)
 223 {
 224         struct drm_control *ctl = data;
 225         int err;
 226
 227         switch (ctl->func) {
 228         case DRM_INST_HANDLER:
 229                 /* Handle drivers whose DRM used to require IRQ setup but the
 230                  * no longer does.
 231                  */
 232                 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
 233                         return 0;
 234                 if (dev->if_version < DRM_IF_VERSION(1, 2) &&
 235                     ctl->irq != dev->irq)
 236                         return EINVAL;
 237                 return drm_irq_install(dev);
 238         case DRM_UNINST_HANDLER:
 239                 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
 240                         return 0;
 241                 DRM_LOCK();
 242                 err = drm_irq_uninstall(dev);
 243                 DRM_UNLOCK();
 244                 return err;
 245         default:
 246                 return EINVAL;
 247         }
 248 }
 249
 250 u32 drm_vblank_count(struct drm_device *dev, int crtc)
 251 {
 252         return atomic_read(&dev->vblank[crtc].count);
 253 }
 254
 255 static void drm_update_vblank_count(struct drm_device *dev, int crtc)
 256 {
 257         u32 cur_vblank, diff;
 258
 259         /*
 260          * Interrupts were disabled prior to this call, so deal with counter
 261          * wrap if needed.
 262          * NOTE!  It's possible we lost a full dev->max_vblank_count events
 263          * here if the register is small or we had vblank interrupts off for
 264          * a long time.
 265          */
 266         cur_vblank = dev->driver->get_vblank_counter(dev, crtc);
 267         diff = cur_vblank - dev->vblank[crtc].last;
 268         if (cur_vblank < dev->vblank[crtc].last) {
 269                 diff += dev->max_vblank_count;
 270
 271                 DRM_DEBUG("vblank[%d].last=0x%x, cur_vblank=0x%x => diff=0x%x\n",
 272                     crtc, dev->vblank[crtc].last, cur_vblank, diff);
 273         }
 274
 275         DRM_DEBUG("enabling vblank interrupts on crtc %d, missed %d\n",
 276             crtc, diff);
 277
 278         atomic_add(diff, &dev->vblank[crtc].count);
 279 }
 280
 281 int drm_vblank_get(struct drm_device *dev, int crtc)
 282 {
 283         int ret = 0;
 284
 285         DRM_SPINLOCK(&dev->vbl_lock);
 286         /* Going from 0->1 means we have to enable interrupts again */
 287         atomic_add_acq_int(&dev->vblank[crtc].refcount, 1);
 288         if (dev->vblank[crtc].refcount == 1 &&
 289             !dev->vblank[crtc].enabled) {
 290                 ret = dev->driver->enable_vblank(dev, crtc);
 291                 DRM_DEBUG("enabling vblank on crtc %d, ret: %d\n", crtc, ret);
 292                 if (ret)
 293                         atomic_dec(&dev->vblank[crtc].refcount);
 294                 else {
 295                         dev->vblank[crtc].enabled = 1;
 296                         drm_update_vblank_count(dev, crtc);
 297                 }
 298         }
 299         DRM_SPINUNLOCK(&dev->vbl_lock);
 300
 301         return ret;
 302 }
 303
 304 void drm_vblank_put(struct drm_device *dev, int crtc)
 305 {
 306         KASSERT(atomic_read(&dev->vblank[crtc].refcount) > 0,
 307             ("invalid refcount"));
 308
 309         /* Last user schedules interrupt disable */
 310         atomic_subtract_acq_int(&dev->vblank[crtc].refcount, 1);
 311
 312         DRM_SPINLOCK(&dev->vbl_lock);
 313         if (dev->vblank[crtc].refcount == 0)
 314             callout_reset(&dev->vblank_disable_timer, 5 * DRM_HZ,
 315                 (timeout_t *)vblank_disable_fn, (void *)dev);
 316         DRM_SPINUNLOCK(&dev->vbl_lock);
 317 }
 318
 319 int drm_modeset_ctl(struct drm_device *dev, void *data,
 320                     struct drm_file *file_priv)
 321 {
 322         struct drm_modeset_ctl *modeset = data;
 323         int crtc, ret = 0;
 324
 325         DRM_DEBUG("num_crtcs=%d\n", dev->num_crtcs);
 326         /* If drm_vblank_init() hasn't been called yet, just no-op */
 327         if (!dev->num_crtcs)
 328                 goto out;
 329
 330         crtc = modeset->crtc;
 331         DRM_DEBUG("crtc=%d\n", crtc);
 332         if (crtc >= dev->num_crtcs) {
 333                 ret = EINVAL;
 334                 goto out;
 335         }
 336
 337         /*
 338          * To avoid all the problems that might happen if interrupts
 339          * were enabled/disabled around or between these calls, we just
 340          * have the kernel take a reference on the CRTC (just once though
 341          * to avoid corrupting the count if multiple, mismatch calls occur),
 342          * so that interrupts remain enabled in the interim.
 343          */
 344         switch (modeset->cmd) {
 345         case _DRM_PRE_MODESET:
 346                 DRM_DEBUG("pre-modeset\n");
 347                 if (!dev->vblank[crtc].inmodeset) {
 348                         dev->vblank[crtc].inmodeset = 0x1;
 349                         if (drm_vblank_get(dev, crtc) == 0)
 350                                 dev->vblank[crtc].inmodeset |= 0x2;
 351                 }
 352                 break;
 353         case _DRM_POST_MODESET:
 354                 DRM_DEBUG("post-modeset\n");
 355                 if (dev->vblank[crtc].inmodeset) {
 356                         DRM_SPINLOCK(&dev->vbl_lock);
 357                         dev->vblank_disable_allowed = 1;
 358                         DRM_SPINUNLOCK(&dev->vbl_lock);
 359
 360                         if (dev->vblank[crtc].inmodeset & 0x2)
 361                                 drm_vblank_put(dev, crtc);
 362
 363                         dev->vblank[crtc].inmodeset = 0;
 364                 }
 365                 break;
 366         default:
 367                 ret = EINVAL;
 368                 break;
 369         }
 370
 371 out:
 372         return ret;
 373 }
 374
 375 int drm_wait_vblank(struct drm_device *dev, void *data, struct drm_file *file_priv)
 376 {
 377         union drm_wait_vblank *vblwait = data;
 378         unsigned int flags, seq, crtc;
 379         int ret = 0;
 380
 381         if (!dev->irq_enabled)
 382                 return EINVAL;
 383
 384         if (vblwait->request.type &
 385             ~(_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK)) {
 386                 DRM_ERROR("Unsupported type value 0x%x, supported mask 0x%x\n",
 387                     vblwait->request.type,
 388                     (_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK));
 389                 return EINVAL;
 390         }
 391
 392         flags = vblwait->request.type & _DRM_VBLANK_FLAGS_MASK;
 393         crtc = flags & _DRM_VBLANK_SECONDARY ? 1 : 0;
 394
 395         if (crtc >= dev->num_crtcs)
 396                 return EINVAL;
 397
 398         ret = drm_vblank_get(dev, crtc);
 399         if (ret) {
 400                 DRM_ERROR("failed to acquire vblank counter, %d\n", ret);
 401                 return ret;
 402         }
 403         seq = drm_vblank_count(dev, crtc);
 404
 405         switch (vblwait->request.type & _DRM_VBLANK_TYPES_MASK) {
 406         case _DRM_VBLANK_RELATIVE:
 407                 vblwait->request.sequence += seq;
 408                 vblwait->request.type &= ~_DRM_VBLANK_RELATIVE;
 409         case _DRM_VBLANK_ABSOLUTE:
 410                 break;
 411         default:
 412                 ret = EINVAL;
 413                 goto done;
 414         }
 415
 416         if ((flags & _DRM_VBLANK_NEXTONMISS) &&
 417             (seq - vblwait->request.sequence) <= (1<<23)) {
 418                 vblwait->request.sequence = seq + 1;
 419         }
 420
 421         if (flags & _DRM_VBLANK_SIGNAL) {
 422                 /* There have never been any consumers */
 423                 ret = EINVAL;
 424         } else {
 425                 DRM_DEBUG("waiting on vblank count %d, crtc %d\n",
 426                     vblwait->request.sequence, crtc);
 427                 for ( ret = 0 ; !ret && !(((drm_vblank_count(dev, crtc) -
 428                     vblwait->request.sequence) <= (1 << 23)) ||
 429                     !dev->irq_enabled) ; ) {
 430                         lwkt_serialize_enter(&dev->irq_lock);
 431                         if (!(((drm_vblank_count(dev, crtc) -
 432                             vblwait->request.sequence) <= (1 << 23)) ||
 433                             !dev->irq_enabled))
 434                                 ret = serialize_sleep(&dev->vblank[crtc].queue,
 435                                     &dev->irq_lock, PCATCH, "vblwtq",
 436                                     DRM_HZ);
 437                         lwkt_serialize_exit(&dev->irq_lock);
 438                 }
 439
 440                 if (ret != EINTR && ret != ERESTART) {
 441                         struct timeval now;
 442
 443                         microtime(&now);
 444                         vblwait->reply.tval_sec = now.tv_sec;
 445                         vblwait->reply.tval_usec = now.tv_usec;
 446                         vblwait->reply.sequence = drm_vblank_count(dev, crtc);
 447                         DRM_DEBUG("returning %d to client, irq_enabled %d\n",
 448                             vblwait->reply.sequence, dev->irq_enabled);
 449                 } else {
 450                         DRM_DEBUG("vblank wait interrupted by signal\n");
 451                 }
 452         }
 453
 454 done:
 455         drm_vblank_put(dev, crtc);
 456         return ret;
 457 }
 458
 459 void drm_handle_vblank(struct drm_device *dev, int crtc)
 460 {
 461         atomic_inc(&dev->vblank[crtc].count);
 462         DRM_WAKEUP(&dev->vblank[crtc].queue);
 463 }
 464