drivers/char/drm/gamma_drv.c

   1 /* gamma.c -- 3dlabs GMX 2000 driver -*- linux-c -*-
   2  * Created: Mon Jan  4 08:58:31 1999 by faith@precisioninsight.com
   3  *
   4  * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
   5  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
   6  * All Rights Reserved.
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a
   9  * copy of this software and associated documentation files (the "Software"),
  10  * to deal in the Software without restriction, including without limitation
  11  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  12  * and/or sell copies of the Software, and to permit persons to whom the
  13  * Software is furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice (including the next
  16  * paragraph) shall be included in all copies or substantial portions of the
  17  * Software.
  18  *
  19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  20  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  22  * PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  23  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  24  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  25  * DEALINGS IN THE SOFTWARE.
  26  *
  27  * Authors:
  28  *    Rickard E. (Rik) Faith <faith@valinux.com>
  29  *
  30  */
  31
  32 #include <linux/config.h>
  33 #include "drmP.h"
  34 #include "gamma_drv.h"
  35
  36 #ifndef PCI_DEVICE_ID_3DLABS_GAMMA
  37 #define PCI_DEVICE_ID_3DLABS_GAMMA 0x0008
  38 #endif
  39 #ifndef PCI_DEVICE_ID_3DLABS_MX
  40 #define PCI_DEVICE_ID_3DLABS_MX 0x0006
  41 #endif
  42
  43 #define GAMMA_NAME       "gamma"
  44 #define GAMMA_DESC       "3dlabs GMX 2000"
  45 #define GAMMA_DATE       "20000910"
  46 #define GAMMA_MAJOR      1
  47 #define GAMMA_MINOR      0
  48 #define GAMMA_PATCHLEVEL 0
  49
  50 static drm_device_t           gamma_device;
  51
  52 static struct file_operations gamma_fops = {
  53 #if LINUX_VERSION_CODE >= 0x020400
  54                                 /* This started being used during 2.4.0-test */
  55         owner:   THIS_MODULE,
  56 #endif
  57         open:    gamma_open,
  58         flush:   drm_flush,
  59         release: gamma_release,
  60         ioctl:   gamma_ioctl,
  61         mmap:    drm_mmap,
  62         read:    drm_read,
  63         fasync:  drm_fasync,
  64         poll:    drm_poll,
  65 };
  66
  67 static struct miscdevice      gamma_misc = {
  68         minor: MISC_DYNAMIC_MINOR,
  69         name:  GAMMA_NAME,
  70         fops:  &gamma_fops,
  71 };
  72
  73 static drm_ioctl_desc_t       gamma_ioctls[] = {
  74         [DRM_IOCTL_NR(DRM_IOCTL_VERSION)]    = { gamma_version,   0, 0 },
  75         [DRM_IOCTL_NR(DRM_IOCTL_GET_UNIQUE)] = { drm_getunique,   0, 0 },
  76         [DRM_IOCTL_NR(DRM_IOCTL_GET_MAGIC)]  = { drm_getmagic,    0, 0 },
  77         [DRM_IOCTL_NR(DRM_IOCTL_IRQ_BUSID)]  = { drm_irq_busid,   0, 1 },
  78
  79         [DRM_IOCTL_NR(DRM_IOCTL_SET_UNIQUE)] = { drm_setunique,   1, 1 },
  80         [DRM_IOCTL_NR(DRM_IOCTL_BLOCK)]      = { drm_block,       1, 1 },
  81         [DRM_IOCTL_NR(DRM_IOCTL_UNBLOCK)]    = { drm_unblock,     1, 1 },
  82         [DRM_IOCTL_NR(DRM_IOCTL_CONTROL)]    = { gamma_control,   1, 1 },
  83         [DRM_IOCTL_NR(DRM_IOCTL_AUTH_MAGIC)] = { drm_authmagic,   1, 1 },
  84         [DRM_IOCTL_NR(DRM_IOCTL_ADD_MAP)]    = { drm_addmap,      1, 1 },
  85         [DRM_IOCTL_NR(DRM_IOCTL_ADD_BUFS)]   = { drm_addbufs,     1, 1 },
  86         [DRM_IOCTL_NR(DRM_IOCTL_MARK_BUFS)]  = { drm_markbufs,    1, 1 },
  87         [DRM_IOCTL_NR(DRM_IOCTL_INFO_BUFS)]  = { drm_infobufs,    1, 0 },
  88         [DRM_IOCTL_NR(DRM_IOCTL_MAP_BUFS)]   = { drm_mapbufs,     1, 0 },
  89         [DRM_IOCTL_NR(DRM_IOCTL_FREE_BUFS)]  = { drm_freebufs,    1, 0 },
  90
  91         [DRM_IOCTL_NR(DRM_IOCTL_ADD_CTX)]    = { drm_addctx,      1, 1 },
  92         [DRM_IOCTL_NR(DRM_IOCTL_RM_CTX)]     = { drm_rmctx,       1, 1 },
  93         [DRM_IOCTL_NR(DRM_IOCTL_MOD_CTX)]    = { drm_modctx,      1, 1 },
  94         [DRM_IOCTL_NR(DRM_IOCTL_GET_CTX)]    = { drm_getctx,      1, 0 },
  95         [DRM_IOCTL_NR(DRM_IOCTL_SWITCH_CTX)] = { drm_switchctx,   1, 1 },
  96         [DRM_IOCTL_NR(DRM_IOCTL_NEW_CTX)]    = { drm_newctx,      1, 1 },
  97         [DRM_IOCTL_NR(DRM_IOCTL_RES_CTX)]    = { drm_resctx,      1, 0 },
  98         [DRM_IOCTL_NR(DRM_IOCTL_ADD_DRAW)]   = { drm_adddraw,     1, 1 },
  99         [DRM_IOCTL_NR(DRM_IOCTL_RM_DRAW)]    = { drm_rmdraw,      1, 1 },
 100         [DRM_IOCTL_NR(DRM_IOCTL_DMA)]        = { gamma_dma,       1, 0 },
 101         [DRM_IOCTL_NR(DRM_IOCTL_LOCK)]       = { gamma_lock,      1, 0 },
 102         [DRM_IOCTL_NR(DRM_IOCTL_UNLOCK)]     = { gamma_unlock,    1, 0 },
 103         [DRM_IOCTL_NR(DRM_IOCTL_FINISH)]     = { drm_finish,      1, 0 },
 104 };
 105 #define GAMMA_IOCTL_COUNT DRM_ARRAY_SIZE(gamma_ioctls)
 106
 107 #ifdef MODULE
 108 static char                   *gamma = NULL;
 109 #endif
 110 static int                    devices = 0;
 111
 112 MODULE_AUTHOR("VA Linux Systems, Inc.");
 113 MODULE_DESCRIPTION("3dlabs GMX 2000");
 114 MODULE_PARM(gamma, "s");
 115 MODULE_PARM(devices, "i");
 116 MODULE_PARM_DESC(devices,
 117                  "devices=x, where x is the number of MX chips on card\n");
 118 #ifndef MODULE
 119 /* gamma_options is called by the kernel to parse command-line options
 120  * passed via the boot-loader (e.g., LILO).  It calls the insmod option
 121  * routine, drm_parse_options.
 122  */
 123
 124
 125 static int __init gamma_options(char *str)
 126 {
 127         drm_parse_options(str);
 128         return 1;
 129 }
 130
 131 __setup("gamma=", gamma_options);
 132 #endif
 133
 134 static int gamma_setup(drm_device_t *dev)
 135 {
 136         int i;
 137
 138         atomic_set(&dev->ioctl_count, 0);
 139         atomic_set(&dev->vma_count, 0);
 140         dev->buf_use      = 0;
 141         atomic_set(&dev->buf_alloc, 0);
 142
 143         drm_dma_setup(dev);
 144
 145         atomic_set(&dev->total_open, 0);
 146         atomic_set(&dev->total_close, 0);
 147         atomic_set(&dev->total_ioctl, 0);
 148         atomic_set(&dev->total_irq, 0);
 149         atomic_set(&dev->total_ctx, 0);
 150         atomic_set(&dev->total_locks, 0);
 151         atomic_set(&dev->total_unlocks, 0);
 152         atomic_set(&dev->total_contends, 0);
 153         atomic_set(&dev->total_sleeps, 0);
 154
 155         for (i = 0; i < DRM_HASH_SIZE; i++) {
 156                 dev->magiclist[i].head = NULL;
 157                 dev->magiclist[i].tail = NULL;
 158         }
 159         dev->maplist        = NULL;
 160         dev->map_count      = 0;
 161         dev->vmalist        = NULL;
 162         dev->lock.hw_lock   = NULL;
 163         init_waitqueue_head(&dev->lock.lock_queue);
 164         dev->queue_count    = 0;
 165         dev->queue_reserved = 0;
 166         dev->queue_slots    = 0;
 167         dev->queuelist      = NULL;
 168         dev->irq            = 0;
 169         dev->context_flag   = 0;
 170         dev->interrupt_flag = 0;
 171         dev->dma_flag       = 0;
 172         dev->last_context   = 0;
 173         dev->last_switch    = 0;
 174         dev->last_checked   = 0;
 175         init_timer(&dev->timer);
 176         init_waitqueue_head(&dev->context_wait);
 177 #if DRM_DMA_HISTO
 178         memset(&dev->histo, 0, sizeof(dev->histo));
 179 #endif
 180         dev->ctx_start      = 0;
 181         dev->lck_start      = 0;
 182
 183         dev->buf_rp       = dev->buf;
 184         dev->buf_wp       = dev->buf;
 185         dev->buf_end      = dev->buf + DRM_BSZ;
 186         dev->buf_async    = NULL;
 187         init_waitqueue_head(&dev->buf_readers);
 188         init_waitqueue_head(&dev->buf_writers);
 189
 190         DRM_DEBUG("\n");
 191
 192         /* The kernel's context could be created here, but is now created
 193            in drm_dma_enqueue.  This is more resource-efficient for
 194            hardware that does not do DMA, but may mean that
 195            drm_select_queue fails between the time the interrupt is
 196            initialized and the time the queues are initialized. */
 197
 198         return 0;
 199 }
 200
 201
 202 static int gamma_takedown(drm_device_t *dev)
 203 {
 204         int               i;
 205         drm_magic_entry_t *pt, *next;
 206         drm_map_t         *map;
 207         drm_vma_entry_t   *vma, *vma_next;
 208
 209         DRM_DEBUG("\n");
 210
 211         if (dev->irq) gamma_irq_uninstall(dev);
 212
 213         down(&dev->struct_sem);
 214         del_timer(&dev->timer);
 215
 216         if (dev->devname) {
 217                 drm_free(dev->devname, strlen(dev->devname)+1, DRM_MEM_DRIVER);
 218                 dev->devname = NULL;
 219         }
 220
 221         if (dev->unique) {
 222                 drm_free(dev->unique, strlen(dev->unique)+1, DRM_MEM_DRIVER);
 223                 dev->unique = NULL;
 224                 dev->unique_len = 0;
 225         }
 226                                 /* Clear pid list */
 227         for (i = 0; i < DRM_HASH_SIZE; i++) {
 228                 for (pt = dev->magiclist[i].head; pt; pt = next) {
 229                         next = pt->next;
 230                         drm_free(pt, sizeof(*pt), DRM_MEM_MAGIC);
 231                 }
 232                 dev->magiclist[i].head = dev->magiclist[i].tail = NULL;
 233         }
 234
 235                                 /* Clear vma list (only built for debugging) */
 236         if (dev->vmalist) {
 237                 for (vma = dev->vmalist; vma; vma = vma_next) {
 238                         vma_next = vma->next;
 239                         drm_free(vma, sizeof(*vma), DRM_MEM_VMAS);
 240                 }
 241                 dev->vmalist = NULL;
 242         }
 243
 244                                 /* Clear map area and mtrr information */
 245         if (dev->maplist) {
 246                 for (i = 0; i < dev->map_count; i++) {
 247                         map = dev->maplist[i];
 248                         switch (map->type) {
 249                         case _DRM_REGISTERS:
 250                         case _DRM_FRAME_BUFFER:
 251 #ifdef CONFIG_MTRR
 252                                 if (map->mtrr >= 0) {
 253                                         int retcode;
 254                                         retcode = mtrr_del(map->mtrr,
 255                                                            map->offset,
 256                                                            map->size);
 257                                         DRM_DEBUG("mtrr_del = %d\n", retcode);
 258                                 }
 259 #endif
 260                                 drm_ioremapfree(map->handle, map->size);
 261                                 break;
 262                         case _DRM_SHM:
 263                                 drm_free_pages((unsigned long)map->handle,
 264                                                drm_order(map->size)
 265                                                - PAGE_SHIFT,
 266                                                DRM_MEM_SAREA);
 267                                 break;
 268                         case _DRM_AGP:
 269                                 /* Do nothing here, because this is all
 270                                    handled in the AGP/GART driver. */
 271                                 break;
 272                         }
 273                         drm_free(map, sizeof(*map), DRM_MEM_MAPS);
 274                 }
 275                 drm_free(dev->maplist,
 276                          dev->map_count * sizeof(*dev->maplist),
 277                          DRM_MEM_MAPS);
 278                 dev->maplist   = NULL;
 279                 dev->map_count = 0;
 280         }
 281
 282         if (dev->queuelist) {
 283                 for (i = 0; i < dev->queue_count; i++) {
 284                         drm_waitlist_destroy(&dev->queuelist[i]->waitlist);
 285                         if (dev->queuelist[i]) {
 286                                 drm_free(dev->queuelist[i],
 287                                          sizeof(*dev->queuelist[0]),
 288                                          DRM_MEM_QUEUES);
 289                                 dev->queuelist[i] = NULL;
 290                         }
 291                 }
 292                 drm_free(dev->queuelist,
 293                          dev->queue_slots * sizeof(*dev->queuelist),
 294                          DRM_MEM_QUEUES);
 295                 dev->queuelist   = NULL;
 296         }
 297
 298         drm_dma_takedown(dev);
 299
 300         dev->queue_count     = 0;
 301         if (dev->lock.hw_lock) {
 302                 dev->lock.hw_lock    = NULL; /* SHM removed */
 303                 dev->lock.pid        = 0;
 304                 wake_up_interruptible(&dev->lock.lock_queue);
 305         }
 306         up(&dev->struct_sem);
 307
 308         return 0;
 309 }
 310
 311 int gamma_found(void)
 312 {
 313         return devices;
 314 }
 315
 316 int gamma_find_devices(void)
 317 {
 318         struct pci_dev *d = NULL, *one = NULL, *two = NULL;
 319
 320         d = pci_find_device(PCI_VENDOR_ID_3DLABS,PCI_DEVICE_ID_3DLABS_GAMMA,d);
 321         if (!d) return 0;
 322
 323         one = pci_find_device(PCI_VENDOR_ID_3DLABS,PCI_DEVICE_ID_3DLABS_MX,d);
 324         if (!one) return 0;
 325
 326         /* Make sure it's on the same card, if not - no MX's found */
 327         if (PCI_SLOT(d->devfn) != PCI_SLOT(one->devfn)) return 0;
 328
 329         two = pci_find_device(PCI_VENDOR_ID_3DLABS,PCI_DEVICE_ID_3DLABS_MX,one);
 330         if (!two) return 1;
 331
 332         /* Make sure it's on the same card, if not - only 1 MX found */
 333         if (PCI_SLOT(d->devfn) != PCI_SLOT(two->devfn)) return 1;
 334
 335         /* Two MX's found - we don't currently support more than 2 */
 336         return 2;
 337 }
 338
 339 /* gamma_init is called via init_module at module load time, or via
 340  * linux/init/main.c (this is not currently supported). */
 341
 342 static int __init gamma_init(void)
 343 {
 344         int                   retcode;
 345         drm_device_t          *dev = &gamma_device;
 346
 347         DRM_DEBUG("\n");
 348
 349         memset((void *)dev, 0, sizeof(*dev));
 350         dev->count_lock   = SPIN_LOCK_UNLOCKED;
 351         sema_init(&dev->struct_sem, 1);
 352
 353 #ifdef MODULE
 354         drm_parse_options(gamma);
 355 #endif
 356         devices = gamma_find_devices();
 357         if (devices == 0) return -1;
 358
 359         if ((retcode = misc_register(&gamma_misc))) {
 360                 DRM_ERROR("Cannot register \"%s\"\n", GAMMA_NAME);
 361                 return retcode;
 362         }
 363         dev->device = MKDEV(MISC_MAJOR, gamma_misc.minor);
 364         dev->name   = GAMMA_NAME;
 365
 366         drm_mem_init();
 367         drm_proc_init(dev);
 368
 369         DRM_INFO("Initialized %s %d.%d.%d %s on minor %d with %d MX devices\n",
 370                  GAMMA_NAME,
 371                  GAMMA_MAJOR,
 372                  GAMMA_MINOR,
 373                  GAMMA_PATCHLEVEL,
 374                  GAMMA_DATE,
 375                  gamma_misc.minor,
 376                  devices);
 377
 378         return 0;
 379 }
 380
 381 /* gamma_cleanup is called via cleanup_module at module unload time. */
 382
 383 static void __exit gamma_cleanup(void)
 384 {
 385         drm_device_t          *dev = &gamma_device;
 386
 387         DRM_DEBUG("\n");
 388
 389         drm_proc_cleanup();
 390         if (misc_deregister(&gamma_misc)) {
 391                 DRM_ERROR("Cannot unload module\n");
 392         } else {
 393                 DRM_INFO("Module unloaded\n");
 394         }
 395         gamma_takedown(dev);
 396 }
 397
 398 module_init(gamma_init);
 399 module_exit(gamma_cleanup);
 400
 401
 402 int gamma_version(struct inode *inode, struct file *filp, unsigned int cmd,
 403                   unsigned long arg)
 404 {
 405         drm_version_t version;
 406         int           len;
 407
 408         if (copy_from_user(&version,
 409                            (drm_version_t *)arg,
 410                            sizeof(version)))
 411                 return -EFAULT;
 412
 413 #define DRM_COPY(name,value)                                 \
 414         len = strlen(value);                                 \
 415         if (len > name##_len) len = name##_len;              \
 416         name##_len = strlen(value);                          \
 417         if (len && name) {                                   \
 418                 if (copy_to_user(name, value, len))          \
 419                         return -EFAULT;                      \
 420         }
 421
 422         version.version_major      = GAMMA_MAJOR;
 423         version.version_minor      = GAMMA_MINOR;
 424         version.version_patchlevel = GAMMA_PATCHLEVEL;
 425
 426         DRM_COPY(version.name, GAMMA_NAME);
 427         DRM_COPY(version.date, GAMMA_DATE);
 428         DRM_COPY(version.desc, GAMMA_DESC);
 429
 430         if (copy_to_user((drm_version_t *)arg,
 431                          &version,
 432                          sizeof(version)))
 433                 return -EFAULT;
 434         return 0;
 435 }
 436
 437 int gamma_open(struct inode *inode, struct file *filp)
 438 {
 439         drm_device_t  *dev    = &gamma_device;
 440         int           retcode = 0;
 441
 442         DRM_DEBUG("open_count = %d\n", dev->open_count);
 443         if (!(retcode = drm_open_helper(inode, filp, dev))) {
 444 #if LINUX_VERSION_CODE < 0x020333
 445                 MOD_INC_USE_COUNT; /* Needed before Linux 2.3.51 */
 446 #endif
 447                 atomic_inc(&dev->total_open);
 448                 spin_lock(&dev->count_lock);
 449                 if (!dev->open_count++) {
 450                         spin_unlock(&dev->count_lock);
 451                         return gamma_setup(dev);
 452                 }
 453                 spin_unlock(&dev->count_lock);
 454         }
 455         return retcode;
 456 }
 457
 458 int gamma_release(struct inode *inode, struct file *filp)
 459 {
 460         drm_file_t    *priv   = filp->private_data;
 461         drm_device_t  *dev;
 462         int           retcode = 0;
 463
 464         lock_kernel();
 465         dev = priv->dev;
 466
 467         DRM_DEBUG("open_count = %d\n", dev->open_count);
 468         if (!(retcode = drm_release(inode, filp))) {
 469 #if LINUX_VERSION_CODE < 0x020333
 470                 MOD_DEC_USE_COUNT; /* Needed before Linux 2.3.51 */
 471 #endif
 472                 atomic_inc(&dev->total_close);
 473                 spin_lock(&dev->count_lock);
 474                 if (!--dev->open_count) {
 475                         if (atomic_read(&dev->ioctl_count) || dev->blocked) {
 476                                 DRM_ERROR("Device busy: %d %d\n",
 477                                           atomic_read(&dev->ioctl_count),
 478                                           dev->blocked);
 479                                 spin_unlock(&dev->count_lock);
 480                                 unlock_kernel();
 481                                 return -EBUSY;
 482                         }
 483                         spin_unlock(&dev->count_lock);
 484                         unlock_kernel();
 485                         return gamma_takedown(dev);
 486                 }
 487                 spin_unlock(&dev->count_lock);
 488         }
 489         unlock_kernel();
 490         return retcode;
 491 }
 492
 493 /* drm_ioctl is called whenever a process performs an ioctl on /dev/drm. */
 494
 495 int gamma_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
 496                 unsigned long arg)
 497 {
 498         int              nr      = DRM_IOCTL_NR(cmd);
 499         drm_file_t       *priv   = filp->private_data;
 500         drm_device_t     *dev    = priv->dev;
 501         int              retcode = 0;
 502         drm_ioctl_desc_t *ioctl;
 503         drm_ioctl_t      *func;
 504
 505         atomic_inc(&dev->ioctl_count);
 506         atomic_inc(&dev->total_ioctl);
 507         ++priv->ioctl_count;
 508
 509         DRM_DEBUG("pid = %d, cmd = 0x%02x, nr = 0x%02x, dev 0x%x, auth = %d\n",
 510                   current->pid, cmd, nr, dev->device, priv->authenticated);
 511
 512         if (nr >= GAMMA_IOCTL_COUNT) {
 513                 retcode = -EINVAL;
 514         } else {
 515                 ioctl     = &gamma_ioctls[nr];
 516                 func      = ioctl->func;
 517
 518                 if (!func) {
 519                         DRM_DEBUG("no function\n");
 520                         retcode = -EINVAL;
 521                 } else if ((ioctl->root_only && !capable(CAP_SYS_ADMIN))
 522                             || (ioctl->auth_needed && !priv->authenticated)) {
 523                         retcode = -EACCES;
 524                 } else {
 525                         retcode = (func)(inode, filp, cmd, arg);
 526                 }
 527         }
 528
 529         atomic_dec(&dev->ioctl_count);
 530         return retcode;
 531 }
 532
 533
 534 int gamma_unlock(struct inode *inode, struct file *filp, unsigned int cmd,
 535                  unsigned long arg)
 536 {
 537         drm_file_t        *priv   = filp->private_data;
 538         drm_device_t      *dev    = priv->dev;
 539         drm_lock_t        lock;
 540
 541         if (copy_from_user(&lock, (drm_lock_t *)arg, sizeof(lock)))
 542                 return -EFAULT;
 543
 544         if (lock.context == DRM_KERNEL_CONTEXT) {
 545                 DRM_ERROR("Process %d using kernel context %d\n",
 546                           current->pid, lock.context);
 547                 return -EINVAL;
 548         }
 549
 550         DRM_DEBUG("%d frees lock (%d holds)\n",
 551                   lock.context,
 552                   _DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock));
 553         atomic_inc(&dev->total_unlocks);
 554         if (_DRM_LOCK_IS_CONT(dev->lock.hw_lock->lock))
 555                 atomic_inc(&dev->total_contends);
 556         drm_lock_transfer(dev, &dev->lock.hw_lock->lock, DRM_KERNEL_CONTEXT);
 557         gamma_dma_schedule(dev, 1);
 558         if (!dev->context_flag) {
 559                 if (drm_lock_free(dev, &dev->lock.hw_lock->lock,
 560                                   DRM_KERNEL_CONTEXT)) {
 561                         DRM_ERROR("\n");
 562                 }
 563         }
 564 #if DRM_DMA_HISTOGRAM
 565         atomic_inc(&dev->histo.lhld[drm_histogram_slot(get_cycles()
 566                                                        - dev->lck_start)]);
 567 #endif
 568
 569         unblock_all_signals();
 570         return 0;
 571 }