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 #include <sys/cdefs.h>
  29 __FBSDID("$FreeBSD$");
  30
  31 /** @file drm_irq.c
  32  * Support code for handling setup/teardown of interrupt handlers and
  33  * handing interrupt handlers off to the drivers.
  34  */
  35
  36 #include "dev/drm/drmP.h"
  37 #include "dev/drm/drm.h"
  38
  39 int drm_irq_by_busid(struct drm_device *dev, void *data,
  40                      struct drm_file *file_priv)
  41 {
  42         struct drm_irq_busid *irq = data;
  43
  44         if ((irq->busnum >> 8) != dev->pci_domain ||
  45             (irq->busnum & 0xff) != dev->pci_bus ||
  46             irq->devnum != dev->pci_slot ||
  47             irq->funcnum != dev->pci_func)
  48                 return EINVAL;
  49
  50         irq->irq = dev->irq;
  51
  52         DRM_DEBUG("%d:%d:%d => IRQ %d\n",
  53             irq->busnum, irq->devnum, irq->funcnum, irq->irq);
  54
  55         return 0;
  56 }
  57
  58 static irqreturn_t
  59 drm_irq_handler_wrap(DRM_IRQ_ARGS)
  60 {
  61         struct drm_device *dev = arg;
  62
  63         DRM_SPINLOCK(&dev->irq_lock);
  64         dev->driver->irq_handler(arg);
  65         DRM_SPINUNLOCK(&dev->irq_lock);
  66 }
  67
  68 static void vblank_disable_fn(void *arg)
  69 {
  70         struct drm_device *dev = (struct drm_device *)arg;
  71         int i;
  72
  73         /* Make sure that we are called with the lock held */
  74         mtx_assert(&dev->vbl_lock, MA_OWNED);
  75
  76         if (callout_pending(&dev->vblank_disable_timer)) {
  77                 /* callout was reset */
  78                 return;
  79         }
  80         if (!callout_active(&dev->vblank_disable_timer)) {
  81                 /* callout was stopped */
  82                 return;
  83         }
  84         callout_deactivate(&dev->vblank_disable_timer);
  85
  86         DRM_DEBUG("vblank_disable: %s\n", dev->vblank_disable_allowed ?
  87                 "allowed" : "denied");
  88         if (!dev->vblank_disable_allowed)
  89                 return;
  90
  91         for (i = 0; i < dev->num_crtcs; i++) {
  92                 if (dev->vblank[i].refcount == 0 &&
  93                     dev->vblank[i].enabled && !dev->vblank[i].inmodeset) {
  94                         DRM_DEBUG("disabling vblank on crtc %d\n", i);
  95                         dev->vblank[i].last =
  96                             dev->driver->get_vblank_counter(dev, i);
  97                         dev->driver->disable_vblank(dev, i);
  98                         dev->vblank[i].enabled = 0;
  99                 }
 100         }
 101 }
 102
 103 void drm_vblank_cleanup(struct drm_device *dev)
 104 {
 105         /* Bail if the driver didn't call drm_vblank_init() */
 106         if (dev->num_crtcs == 0)
 107                 return;
 108
 109         DRM_SPINLOCK(&dev->vbl_lock);
 110         callout_stop(&dev->vblank_disable_timer);
 111         DRM_SPINUNLOCK(&dev->vbl_lock);
 112
 113         callout_drain(&dev->vblank_disable_timer);
 114
 115         DRM_SPINLOCK(&dev->vbl_lock);
 116         vblank_disable_fn((void *)dev);
 117         DRM_SPINUNLOCK(&dev->vbl_lock);
 118
 119         free(dev->vblank, DRM_MEM_DRIVER);
 120
 121         dev->num_crtcs = 0;
 122 }
 123
 124 int drm_vblank_init(struct drm_device *dev, int num_crtcs)
 125 {
 126         int i, ret = ENOMEM;
 127
 128         callout_init_mtx(&dev->vblank_disable_timer, &dev->vbl_lock, 0);
 129         dev->num_crtcs = num_crtcs;
 130
 131         dev->vblank = malloc(sizeof(struct drm_vblank_info) * num_crtcs,
 132             DRM_MEM_DRIVER, M_NOWAIT | M_ZERO);
 133         if (!dev->vblank)
 134             goto err;
 135
 136         DRM_DEBUG("\n");
 137
 138         /* Zero per-crtc vblank stuff */
 139         DRM_SPINLOCK(&dev->vbl_lock);
 140         for (i = 0; i < num_crtcs; i++) {
 141                 DRM_INIT_WAITQUEUE(&dev->vblank[i].queue);
 142                 dev->vblank[i].refcount = 0;
 143                 atomic_store_rel_32(&dev->vblank[i].count, 0);
 144         }
 145         dev->vblank_disable_allowed = 0;
 146         DRM_SPINUNLOCK(&dev->vbl_lock);
 147
 148         return 0;
 149
 150 err:
 151         drm_vblank_cleanup(dev);
 152         return ret;
 153 }
 154
 155 int drm_irq_install(struct drm_device *dev)
 156 {
 157         int crtc, retcode;
 158
 159         if (dev->irq == 0 || dev->dev_private == NULL)
 160                 return EINVAL;
 161
 162         DRM_DEBUG("irq=%d\n", dev->irq);
 163
 164         DRM_LOCK();
 165         if (dev->irq_enabled) {
 166                 DRM_UNLOCK();
 167                 return EBUSY;
 168         }
 169         dev->irq_enabled = 1;
 170
 171         dev->context_flag = 0;
 172
 173         /* Before installing handler */
 174         dev->driver->irq_preinstall(dev);
 175         DRM_UNLOCK();
 176
 177         /* Install handler */
 178 #if __FreeBSD_version >= 700031
 179         retcode = bus_setup_intr(dev->device, dev->irqr,
 180                                  INTR_TYPE_TTY | INTR_MPSAFE,
 181                                  NULL, drm_irq_handler_wrap, dev, &dev->irqh);
 182 #else
 183         retcode = bus_setup_intr(dev->device, dev->irqr,
 184                                  INTR_TYPE_TTY | INTR_MPSAFE,
 185                                  drm_irq_handler_wrap, dev, &dev->irqh);
 186 #endif
 187         if (retcode != 0)
 188                 goto err;
 189
 190         /* After installing handler */
 191         DRM_LOCK();
 192         dev->driver->irq_postinstall(dev);
 193         DRM_UNLOCK();
 194         if (dev->driver->enable_vblank) {
 195                 DRM_SPINLOCK(&dev->vbl_lock);
 196                 for( crtc = 0 ; crtc < dev->num_crtcs ; crtc++) {
 197                         if (dev->driver->enable_vblank(dev, crtc) == 0) {
 198                                 dev->vblank[crtc].enabled = 1;
 199                         }
 200                 }
 201                 callout_reset(&dev->vblank_disable_timer, 5 * DRM_HZ,
 202                     (timeout_t *)vblank_disable_fn, (void *)dev);
 203                 DRM_SPINUNLOCK(&dev->vbl_lock);
 204         }
 205
 206         return 0;
 207 err:
 208         DRM_LOCK();
 209         dev->irq_enabled = 0;
 210         DRM_UNLOCK();
 211
 212         return retcode;
 213 }
 214
 215 int drm_irq_uninstall(struct drm_device *dev)
 216 {
 217         int crtc;
 218
 219         if (!dev->irq_enabled)
 220                 return EINVAL;
 221
 222         dev->irq_enabled = 0;
 223
 224         /*
 225         * Wake up any waiters so they don't hang.
 226         */
 227         DRM_SPINLOCK(&dev->vbl_lock);
 228         for (crtc = 0; crtc < dev->num_crtcs; crtc++) {
 229                 if (dev->vblank[crtc].enabled) {
 230                         DRM_WAKEUP(&dev->vblank[crtc].queue);
 231                         dev->vblank[crtc].last =
 232                             dev->driver->get_vblank_counter(dev, crtc);
 233                         dev->vblank[crtc].enabled = 0;
 234                 }
 235         }
 236         DRM_SPINUNLOCK(&dev->vbl_lock);
 237
 238         DRM_DEBUG("irq=%d\n", dev->irq);
 239
 240         dev->driver->irq_uninstall(dev);
 241
 242         DRM_UNLOCK();
 243         bus_teardown_intr(dev->device, dev->irqr, dev->irqh);
 244         DRM_LOCK();
 245
 246         return 0;
 247 }
 248
 249 int drm_control(struct drm_device *dev, void *data, struct drm_file *file_priv)
 250 {
 251         struct drm_control *ctl = data;
 252         int err;
 253
 254         switch (ctl->func) {
 255         case DRM_INST_HANDLER:
 256                 /* Handle drivers whose DRM used to require IRQ setup but the
 257                  * no longer does.
 258                  */
 259                 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
 260                         return 0;
 261                 if (dev->if_version < DRM_IF_VERSION(1, 2) &&
 262                     ctl->irq != dev->irq)
 263                         return EINVAL;
 264                 return drm_irq_install(dev);
 265         case DRM_UNINST_HANDLER:
 266                 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
 267                         return 0;
 268                 DRM_LOCK();
 269                 err = drm_irq_uninstall(dev);
 270                 DRM_UNLOCK();
 271                 return err;
 272         default:
 273                 return EINVAL;
 274         }
 275 }
 276
 277 u32 drm_vblank_count(struct drm_device *dev, int crtc)
 278 {
 279         return atomic_load_acq_32(&dev->vblank[crtc].count);
 280 }
 281
 282 static void drm_update_vblank_count(struct drm_device *dev, int crtc)
 283 {
 284         u32 cur_vblank, diff;
 285
 286         /*
 287          * Interrupts were disabled prior to this call, so deal with counter
 288          * wrap if needed.
 289          * NOTE!  It's possible we lost a full dev->max_vblank_count events
 290          * here if the register is small or we had vblank interrupts off for
 291          * a long time.
 292          */
 293         cur_vblank = dev->driver->get_vblank_counter(dev, crtc);
 294         diff = cur_vblank - dev->vblank[crtc].last;
 295         if (cur_vblank < dev->vblank[crtc].last) {
 296                 diff += dev->max_vblank_count;
 297
 298                 DRM_DEBUG("vblank[%d].last=0x%x, cur_vblank=0x%x => diff=0x%x\n",
 299                     crtc, dev->vblank[crtc].last, cur_vblank, diff);
 300         }
 301
 302         DRM_DEBUG("enabling vblank interrupts on crtc %d, missed %d\n",
 303             crtc, diff);
 304
 305         atomic_add_rel_32(&dev->vblank[crtc].count, diff);
 306 }
 307
 308 int drm_vblank_get(struct drm_device *dev, int crtc)
 309 {
 310         int ret = 0;
 311
 312         /* Make sure that we are called with the lock held */
 313         mtx_assert(&dev->vbl_lock, MA_OWNED);
 314
 315         /* Going from 0->1 means we have to enable interrupts again */
 316         if (++dev->vblank[crtc].refcount == 1 &&
 317             !dev->vblank[crtc].enabled) {
 318                 ret = dev->driver->enable_vblank(dev, crtc);
 319                 DRM_DEBUG("enabling vblank on crtc %d, ret: %d\n", crtc, ret);
 320                 if (ret)
 321                         --dev->vblank[crtc].refcount;
 322                 else {
 323                         dev->vblank[crtc].enabled = 1;
 324                         drm_update_vblank_count(dev, crtc);
 325                 }
 326         }
 327
 328         if (dev->vblank[crtc].enabled)
 329                 dev->vblank[crtc].last =
 330                     dev->driver->get_vblank_counter(dev, crtc);
 331
 332         return ret;
 333 }
 334
 335 void drm_vblank_put(struct drm_device *dev, int crtc)
 336 {
 337         /* Make sure that we are called with the lock held */
 338         mtx_assert(&dev->vbl_lock, MA_OWNED);
 339
 340         KASSERT(dev->vblank[crtc].refcount > 0,
 341             ("invalid refcount"));
 342
 343         /* Last user schedules interrupt disable */
 344         if (--dev->vblank[crtc].refcount == 0)
 345             callout_reset(&dev->vblank_disable_timer, 5 * DRM_HZ,
 346                 (timeout_t *)vblank_disable_fn, (void *)dev);
 347 }
 348
 349 int drm_modeset_ctl(struct drm_device *dev, void *data,
 350                     struct drm_file *file_priv)
 351 {
 352         struct drm_modeset_ctl *modeset = data;
 353         int crtc, ret = 0;
 354
 355         /* If drm_vblank_init() hasn't been called yet, just no-op */
 356         if (!dev->num_crtcs)
 357                 goto out;
 358
 359         crtc = modeset->crtc;
 360         if (crtc >= dev->num_crtcs) {
 361                 ret = EINVAL;
 362                 goto out;
 363         }
 364
 365         /*
 366          * To avoid all the problems that might happen if interrupts
 367          * were enabled/disabled around or between these calls, we just
 368          * have the kernel take a reference on the CRTC (just once though
 369          * to avoid corrupting the count if multiple, mismatch calls occur),
 370          * so that interrupts remain enabled in the interim.
 371          */
 372         switch (modeset->cmd) {
 373         case _DRM_PRE_MODESET:
 374                 DRM_DEBUG("pre-modeset, crtc %d\n", crtc);
 375                 DRM_SPINLOCK(&dev->vbl_lock);
 376                 if (!dev->vblank[crtc].inmodeset) {
 377                         dev->vblank[crtc].inmodeset = 0x1;
 378                         if (drm_vblank_get(dev, crtc) == 0)
 379                                 dev->vblank[crtc].inmodeset |= 0x2;
 380                 }
 381                 DRM_SPINUNLOCK(&dev->vbl_lock);
 382                 break;
 383         case _DRM_POST_MODESET:
 384                 DRM_DEBUG("post-modeset, crtc %d\n", crtc);
 385                 DRM_SPINLOCK(&dev->vbl_lock);
 386                 if (dev->vblank[crtc].inmodeset) {
 387                         if (dev->vblank[crtc].inmodeset & 0x2)
 388                                 drm_vblank_put(dev, crtc);
 389                         dev->vblank[crtc].inmodeset = 0;
 390                 }
 391                 dev->vblank_disable_allowed = 1;
 392                 DRM_SPINUNLOCK(&dev->vbl_lock);
 393                 break;
 394         default:
 395                 ret = EINVAL;
 396                 break;
 397         }
 398
 399 out:
 400         return ret;
 401 }
 402
 403 int drm_wait_vblank(struct drm_device *dev, void *data, struct drm_file *file_priv)
 404 {
 405         union drm_wait_vblank *vblwait = data;
 406         unsigned int flags, seq, crtc;
 407         int ret = 0;
 408
 409         if (!dev->irq_enabled)
 410                 return EINVAL;
 411
 412         if (vblwait->request.type &
 413             ~(_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK)) {
 414                 DRM_ERROR("Unsupported type value 0x%x, supported mask 0x%x\n",
 415                     vblwait->request.type,
 416                     (_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK));
 417                 return EINVAL;
 418         }
 419
 420         flags = vblwait->request.type & _DRM_VBLANK_FLAGS_MASK;
 421         crtc = flags & _DRM_VBLANK_SECONDARY ? 1 : 0;
 422
 423         if (crtc >= dev->num_crtcs)
 424                 return EINVAL;
 425
 426         DRM_SPINLOCK(&dev->vbl_lock);
 427         ret = drm_vblank_get(dev, crtc);
 428         DRM_SPINUNLOCK(&dev->vbl_lock);
 429         if (ret) {
 430                 DRM_ERROR("failed to acquire vblank counter, %d\n", ret);
 431                 return ret;
 432         }
 433         seq = drm_vblank_count(dev, crtc);
 434
 435         switch (vblwait->request.type & _DRM_VBLANK_TYPES_MASK) {
 436         case _DRM_VBLANK_RELATIVE:
 437                 vblwait->request.sequence += seq;
 438                 vblwait->request.type &= ~_DRM_VBLANK_RELATIVE;
 439         case _DRM_VBLANK_ABSOLUTE:
 440                 break;
 441         default:
 442                 ret = EINVAL;
 443                 goto done;
 444         }
 445
 446         if ((flags & _DRM_VBLANK_NEXTONMISS) &&
 447             (seq - vblwait->request.sequence) <= (1<<23)) {
 448                 vblwait->request.sequence = seq + 1;
 449         }
 450
 451         if (flags & _DRM_VBLANK_SIGNAL) {
 452                 /* There have never been any consumers */
 453                 ret = EINVAL;
 454         } else {
 455                 DRM_DEBUG("waiting on vblank count %d, crtc %d\n",
 456                     vblwait->request.sequence, crtc);
 457                 for ( ret = 0 ; !ret && !(((drm_vblank_count(dev, crtc) -
 458                     vblwait->request.sequence) <= (1 << 23)) ||
 459                     !dev->irq_enabled) ; ) {
 460                         mtx_lock(&dev->irq_lock);
 461                         if (!(((drm_vblank_count(dev, crtc) -
 462                             vblwait->request.sequence) <= (1 << 23)) ||
 463                             !dev->irq_enabled))
 464                                 ret = mtx_sleep(&dev->vblank[crtc].queue,
 465                                     &dev->irq_lock, PCATCH, "vblwtq",
 466                                     DRM_HZ);
 467                         mtx_unlock(&dev->irq_lock);
 468                 }
 469
 470                 if (ret != EINTR && ret != ERESTART) {
 471                         struct timeval now;
 472
 473                         microtime(&now);
 474                         vblwait->reply.tval_sec = now.tv_sec;
 475                         vblwait->reply.tval_usec = now.tv_usec;
 476                         vblwait->reply.sequence = drm_vblank_count(dev, crtc);
 477                         DRM_DEBUG("returning %d to client, irq_enabled %d\n",
 478                             vblwait->reply.sequence, dev->irq_enabled);
 479                 } else {
 480                         DRM_DEBUG("vblank wait interrupted by signal\n");
 481                 }
 482         }
 483
 484 done:
 485         DRM_SPINLOCK(&dev->vbl_lock);
 486         drm_vblank_put(dev, crtc);
 487         DRM_SPINUNLOCK(&dev->vbl_lock);
 488
 489         return ret;
 490 }
 491
 492 void drm_handle_vblank(struct drm_device *dev, int crtc)
 493 {
 494         atomic_add_rel_32(&dev->vblank[crtc].count, 1);
 495         DRM_WAKEUP(&dev->vblank[crtc].queue);
 496 }
 497