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         retcode = bus_setup_intr(dev->device, dev->irqr,
 179                                  INTR_TYPE_TTY | INTR_MPSAFE,
 180                                  NULL, drm_irq_handler_wrap, dev, &dev->irqh);
 181         if (retcode != 0)
 182                 goto err;
 183
 184         /* After installing handler */
 185         DRM_LOCK();
 186         dev->driver->irq_postinstall(dev);
 187         DRM_UNLOCK();
 188         if (dev->driver->enable_vblank) {
 189                 DRM_SPINLOCK(&dev->vbl_lock);
 190                 for( crtc = 0 ; crtc < dev->num_crtcs ; crtc++) {
 191                         if (dev->driver->enable_vblank(dev, crtc) == 0) {
 192                                 dev->vblank[crtc].enabled = 1;
 193                         }
 194                 }
 195                 callout_reset(&dev->vblank_disable_timer, 5 * DRM_HZ,
 196                     (timeout_t *)vblank_disable_fn, (void *)dev);
 197                 DRM_SPINUNLOCK(&dev->vbl_lock);
 198         }
 199
 200         return 0;
 201 err:
 202         DRM_LOCK();
 203         dev->irq_enabled = 0;
 204         DRM_UNLOCK();
 205
 206         return retcode;
 207 }
 208
 209 int drm_irq_uninstall(struct drm_device *dev)
 210 {
 211         int crtc;
 212
 213         if (!dev->irq_enabled)
 214                 return EINVAL;
 215
 216         dev->irq_enabled = 0;
 217
 218         /*
 219         * Wake up any waiters so they don't hang.
 220         */
 221         DRM_SPINLOCK(&dev->vbl_lock);
 222         for (crtc = 0; crtc < dev->num_crtcs; crtc++) {
 223                 if (dev->vblank[crtc].enabled) {
 224                         DRM_WAKEUP(&dev->vblank[crtc].queue);
 225                         dev->vblank[crtc].last =
 226                             dev->driver->get_vblank_counter(dev, crtc);
 227                         dev->vblank[crtc].enabled = 0;
 228                 }
 229         }
 230         DRM_SPINUNLOCK(&dev->vbl_lock);
 231
 232         DRM_DEBUG("irq=%d\n", dev->irq);
 233
 234         dev->driver->irq_uninstall(dev);
 235
 236         DRM_UNLOCK();
 237         bus_teardown_intr(dev->device, dev->irqr, dev->irqh);
 238         DRM_LOCK();
 239
 240         return 0;
 241 }
 242
 243 int drm_control(struct drm_device *dev, void *data, struct drm_file *file_priv)
 244 {
 245         struct drm_control *ctl = data;
 246         int err;
 247
 248         switch (ctl->func) {
 249         case DRM_INST_HANDLER:
 250                 /* Handle drivers whose DRM used to require IRQ setup but the
 251                  * no longer does.
 252                  */
 253                 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
 254                         return 0;
 255                 if (dev->if_version < DRM_IF_VERSION(1, 2) &&
 256                     ctl->irq != dev->irq)
 257                         return EINVAL;
 258                 return drm_irq_install(dev);
 259         case DRM_UNINST_HANDLER:
 260                 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
 261                         return 0;
 262                 DRM_LOCK();
 263                 err = drm_irq_uninstall(dev);
 264                 DRM_UNLOCK();
 265                 return err;
 266         default:
 267                 return EINVAL;
 268         }
 269 }
 270
 271 u32 drm_vblank_count(struct drm_device *dev, int crtc)
 272 {
 273         return atomic_load_acq_32(&dev->vblank[crtc].count);
 274 }
 275
 276 static void drm_update_vblank_count(struct drm_device *dev, int crtc)
 277 {
 278         u32 cur_vblank, diff;
 279
 280         /*
 281          * Interrupts were disabled prior to this call, so deal with counter
 282          * wrap if needed.
 283          * NOTE!  It's possible we lost a full dev->max_vblank_count events
 284          * here if the register is small or we had vblank interrupts off for
 285          * a long time.
 286          */
 287         cur_vblank = dev->driver->get_vblank_counter(dev, crtc);
 288         diff = cur_vblank - dev->vblank[crtc].last;
 289         if (cur_vblank < dev->vblank[crtc].last) {
 290                 diff += dev->max_vblank_count;
 291
 292                 DRM_DEBUG("vblank[%d].last=0x%x, cur_vblank=0x%x => diff=0x%x\n",
 293                     crtc, dev->vblank[crtc].last, cur_vblank, diff);
 294         }
 295
 296         DRM_DEBUG("enabling vblank interrupts on crtc %d, missed %d\n",
 297             crtc, diff);
 298
 299         atomic_add_rel_32(&dev->vblank[crtc].count, diff);
 300 }
 301
 302 int drm_vblank_get(struct drm_device *dev, int crtc)
 303 {
 304         int ret = 0;
 305
 306         /* Make sure that we are called with the lock held */
 307         mtx_assert(&dev->vbl_lock, MA_OWNED);
 308
 309         /* Going from 0->1 means we have to enable interrupts again */
 310         if (++dev->vblank[crtc].refcount == 1 &&
 311             !dev->vblank[crtc].enabled) {
 312                 ret = dev->driver->enable_vblank(dev, crtc);
 313                 DRM_DEBUG("enabling vblank on crtc %d, ret: %d\n", crtc, ret);
 314                 if (ret)
 315                         --dev->vblank[crtc].refcount;
 316                 else {
 317                         dev->vblank[crtc].enabled = 1;
 318                         drm_update_vblank_count(dev, crtc);
 319                 }
 320         }
 321
 322         if (dev->vblank[crtc].enabled)
 323                 dev->vblank[crtc].last =
 324                     dev->driver->get_vblank_counter(dev, crtc);
 325
 326         return ret;
 327 }
 328
 329 void drm_vblank_put(struct drm_device *dev, int crtc)
 330 {
 331         /* Make sure that we are called with the lock held */
 332         mtx_assert(&dev->vbl_lock, MA_OWNED);
 333
 334         KASSERT(dev->vblank[crtc].refcount > 0,
 335             ("invalid refcount"));
 336
 337         /* Last user schedules interrupt disable */
 338         if (--dev->vblank[crtc].refcount == 0)
 339             callout_reset(&dev->vblank_disable_timer, 5 * DRM_HZ,
 340                 (timeout_t *)vblank_disable_fn, (void *)dev);
 341 }
 342
 343 int drm_modeset_ctl(struct drm_device *dev, void *data,
 344                     struct drm_file *file_priv)
 345 {
 346         struct drm_modeset_ctl *modeset = data;
 347         int crtc, ret = 0;
 348
 349         /* If drm_vblank_init() hasn't been called yet, just no-op */
 350         if (!dev->num_crtcs)
 351                 goto out;
 352
 353         crtc = modeset->crtc;
 354         if (crtc >= dev->num_crtcs) {
 355                 ret = EINVAL;
 356                 goto out;
 357         }
 358
 359         /*
 360          * To avoid all the problems that might happen if interrupts
 361          * were enabled/disabled around or between these calls, we just
 362          * have the kernel take a reference on the CRTC (just once though
 363          * to avoid corrupting the count if multiple, mismatch calls occur),
 364          * so that interrupts remain enabled in the interim.
 365          */
 366         switch (modeset->cmd) {
 367         case _DRM_PRE_MODESET:
 368                 DRM_DEBUG("pre-modeset, crtc %d\n", crtc);
 369                 DRM_SPINLOCK(&dev->vbl_lock);
 370                 if (!dev->vblank[crtc].inmodeset) {
 371                         dev->vblank[crtc].inmodeset = 0x1;
 372                         if (drm_vblank_get(dev, crtc) == 0)
 373                                 dev->vblank[crtc].inmodeset |= 0x2;
 374                 }
 375                 DRM_SPINUNLOCK(&dev->vbl_lock);
 376                 break;
 377         case _DRM_POST_MODESET:
 378                 DRM_DEBUG("post-modeset, crtc %d\n", crtc);
 379                 DRM_SPINLOCK(&dev->vbl_lock);
 380                 if (dev->vblank[crtc].inmodeset) {
 381                         if (dev->vblank[crtc].inmodeset & 0x2)
 382                                 drm_vblank_put(dev, crtc);
 383                         dev->vblank[crtc].inmodeset = 0;
 384                 }
 385                 dev->vblank_disable_allowed = 1;
 386                 DRM_SPINUNLOCK(&dev->vbl_lock);
 387                 break;
 388         default:
 389                 ret = EINVAL;
 390                 break;
 391         }
 392
 393 out:
 394         return ret;
 395 }
 396
 397 int drm_wait_vblank(struct drm_device *dev, void *data, struct drm_file *file_priv)
 398 {
 399         union drm_wait_vblank *vblwait = data;
 400         unsigned int flags, seq, crtc;
 401         int ret = 0;
 402
 403         if (!dev->irq_enabled)
 404                 return EINVAL;
 405
 406         if (vblwait->request.type &
 407             ~(_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK)) {
 408                 DRM_ERROR("Unsupported type value 0x%x, supported mask 0x%x\n",
 409                     vblwait->request.type,
 410                     (_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK));
 411                 return EINVAL;
 412         }
 413
 414         flags = vblwait->request.type & _DRM_VBLANK_FLAGS_MASK;
 415         crtc = flags & _DRM_VBLANK_SECONDARY ? 1 : 0;
 416
 417         if (crtc >= dev->num_crtcs)
 418                 return EINVAL;
 419
 420         DRM_SPINLOCK(&dev->vbl_lock);
 421         ret = drm_vblank_get(dev, crtc);
 422         DRM_SPINUNLOCK(&dev->vbl_lock);
 423         if (ret) {
 424                 DRM_ERROR("failed to acquire vblank counter, %d\n", ret);
 425                 return ret;
 426         }
 427         seq = drm_vblank_count(dev, crtc);
 428
 429         switch (vblwait->request.type & _DRM_VBLANK_TYPES_MASK) {
 430         case _DRM_VBLANK_RELATIVE:
 431                 vblwait->request.sequence += seq;
 432                 vblwait->request.type &= ~_DRM_VBLANK_RELATIVE;
 433         case _DRM_VBLANK_ABSOLUTE:
 434                 break;
 435         default:
 436                 ret = EINVAL;
 437                 goto done;
 438         }
 439
 440         if ((flags & _DRM_VBLANK_NEXTONMISS) &&
 441             (seq - vblwait->request.sequence) <= (1<<23)) {
 442                 vblwait->request.sequence = seq + 1;
 443         }
 444
 445         if (flags & _DRM_VBLANK_SIGNAL) {
 446                 /* There have never been any consumers */
 447                 ret = EINVAL;
 448         } else {
 449                 DRM_DEBUG("waiting on vblank count %d, crtc %d\n",
 450                     vblwait->request.sequence, crtc);
 451                 for ( ret = 0 ; !ret && !(((drm_vblank_count(dev, crtc) -
 452                     vblwait->request.sequence) <= (1 << 23)) ||
 453                     !dev->irq_enabled) ; ) {
 454                         mtx_lock(&dev->irq_lock);
 455                         if (!(((drm_vblank_count(dev, crtc) -
 456                             vblwait->request.sequence) <= (1 << 23)) ||
 457                             !dev->irq_enabled))
 458                                 ret = mtx_sleep(&dev->vblank[crtc].queue,
 459                                     &dev->irq_lock, PCATCH, "vblwtq",
 460                                     DRM_HZ);
 461                         mtx_unlock(&dev->irq_lock);
 462                 }
 463
 464                 if (ret != EINTR && ret != ERESTART) {
 465                         struct timeval now;
 466
 467                         microtime(&now);
 468                         vblwait->reply.tval_sec = now.tv_sec;
 469                         vblwait->reply.tval_usec = now.tv_usec;
 470                         vblwait->reply.sequence = drm_vblank_count(dev, crtc);
 471                         DRM_DEBUG("returning %d to client, irq_enabled %d\n",
 472                             vblwait->reply.sequence, dev->irq_enabled);
 473                 } else {
 474                         DRM_DEBUG("vblank wait interrupted by signal\n");
 475                 }
 476         }
 477
 478 done:
 479         DRM_SPINLOCK(&dev->vbl_lock);
 480         drm_vblank_put(dev, crtc);
 481         DRM_SPINUNLOCK(&dev->vbl_lock);
 482
 483         return ret;
 484 }
 485
 486 void drm_handle_vblank(struct drm_device *dev, int crtc)
 487 {
 488         atomic_add_rel_32(&dev->vblank[crtc].count, 1);
 489         DRM_WAKEUP(&dev->vblank[crtc].queue);
 490 }
 491