drivers/char/drm/i915_irq.c

   1 /* i915_irq.c -- IRQ support for the I915 -*- linux-c -*-
   2  */
   3 /*
   4  * Copyright 2003 Tungsten Graphics, Inc., Cedar Park, Texas.
   5  * All Rights Reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the
   9  * "Software"), to deal in the Software without restriction, including
  10  * without limitation the rights to use, copy, modify, merge, publish,
  11  * distribute, sub license, and/or sell copies of the Software, and to
  12  * permit persons to whom the Software is furnished to do so, subject to
  13  * the following conditions:
  14  *
  15  * The above copyright notice and this permission notice (including the
  16  * next paragraph) shall be included in all copies or substantial portions
  17  * of the Software.
  18  *
  19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  20  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  21  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  22  * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
  23  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  24  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  25  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  26  *
  27  */
  28
  29 #include "drmP.h"
  30 #include "drm.h"
  31 #include "i915_drm.h"
  32 #include "i915_drv.h"
  33
  34 #define USER_INT_FLAG (1<<1)
  35 #define VSYNC_PIPEB_FLAG (1<<5)
  36 #define VSYNC_PIPEA_FLAG (1<<7)
  37
  38 #define MAX_NOPID ((u32)~0)
  39
  40 /**
  41  * Emit blits for scheduled buffer swaps.
  42  *
  43  * This function will be called with the HW lock held.
  44  */
  45 static void i915_vblank_tasklet(drm_device_t *dev)
  46 {
  47         drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
  48         unsigned long irqflags;
  49         struct list_head *list, *tmp, hits, *hit;
  50         int nhits, nrects, slice[2], upper[2], lower[2], i;
  51         unsigned counter[2] = { atomic_read(&dev->vbl_received),
  52                                 atomic_read(&dev->vbl_received2) };
  53         drm_drawable_info_t *drw;
  54         drm_i915_sarea_t *sarea_priv = dev_priv->sarea_priv;
  55         u32 cpp = dev_priv->cpp;
  56         u32 cmd = (cpp == 4) ? (XY_SRC_COPY_BLT_CMD |
  57                                 XY_SRC_COPY_BLT_WRITE_ALPHA |
  58                                 XY_SRC_COPY_BLT_WRITE_RGB)
  59                              : XY_SRC_COPY_BLT_CMD;
  60         u32 pitchropcpp = (sarea_priv->pitch * cpp) | (0xcc << 16) |
  61                           (cpp << 23) | (1 << 24);
  62         RING_LOCALS;
  63
  64         DRM_DEBUG("\n");
  65
  66         INIT_LIST_HEAD(&hits);
  67
  68         nhits = nrects = 0;
  69
  70         spin_lock_irqsave(&dev_priv->swaps_lock, irqflags);
  71
  72         /* Find buffer swaps scheduled for this vertical blank */
  73         list_for_each_safe(list, tmp, &dev_priv->vbl_swaps.head) {
  74                 drm_i915_vbl_swap_t *vbl_swap =
  75                         list_entry(list, drm_i915_vbl_swap_t, head);
  76
  77                 if ((counter[vbl_swap->pipe] - vbl_swap->sequence) > (1<<23))
  78                         continue;
  79
  80                 list_del(list);
  81                 dev_priv->swaps_pending--;
  82
  83                 spin_unlock(&dev_priv->swaps_lock);
  84                 spin_lock(&dev->drw_lock);
  85
  86                 drw = drm_get_drawable_info(dev, vbl_swap->drw_id);
  87
  88                 if (!drw) {
  89                         spin_unlock(&dev->drw_lock);
  90                         drm_free(vbl_swap, sizeof(*vbl_swap), DRM_MEM_DRIVER);
  91                         spin_lock(&dev_priv->swaps_lock);
  92                         continue;
  93                 }
  94
  95                 list_for_each(hit, &hits) {
  96                         drm_i915_vbl_swap_t *swap_cmp =
  97                                 list_entry(hit, drm_i915_vbl_swap_t, head);
  98                         drm_drawable_info_t *drw_cmp =
  99                                 drm_get_drawable_info(dev, swap_cmp->drw_id);
 100
 101                         if (drw_cmp &&
 102                             drw_cmp->rects[0].y1 > drw->rects[0].y1) {
 103                                 list_add_tail(list, hit);
 104                                 break;
 105                         }
 106                 }
 107
 108                 spin_unlock(&dev->drw_lock);
 109
 110                 /* List of hits was empty, or we reached the end of it */
 111                 if (hit == &hits)
 112                         list_add_tail(list, hits.prev);
 113
 114                 nhits++;
 115
 116                 spin_lock(&dev_priv->swaps_lock);
 117         }
 118
 119         if (nhits == 0) {
 120                 spin_unlock_irqrestore(&dev_priv->swaps_lock, irqflags);
 121                 return;
 122         }
 123
 124         spin_unlock(&dev_priv->swaps_lock);
 125
 126         i915_kernel_lost_context(dev);
 127
 128         BEGIN_LP_RING(6);
 129
 130         OUT_RING(GFX_OP_DRAWRECT_INFO);
 131         OUT_RING(0);
 132         OUT_RING(0);
 133         OUT_RING(sarea_priv->width | sarea_priv->height << 16);
 134         OUT_RING(sarea_priv->width | sarea_priv->height << 16);
 135         OUT_RING(0);
 136
 137         ADVANCE_LP_RING();
 138
 139         sarea_priv->ctxOwner = DRM_KERNEL_CONTEXT;
 140
 141         upper[0] = upper[1] = 0;
 142         slice[0] = max(sarea_priv->pipeA_h / nhits, 1);
 143         slice[1] = max(sarea_priv->pipeB_h / nhits, 1);
 144         lower[0] = sarea_priv->pipeA_y + slice[0];
 145         lower[1] = sarea_priv->pipeB_y + slice[0];
 146
 147         spin_lock(&dev->drw_lock);
 148
 149         /* Emit blits for buffer swaps, partitioning both outputs into as many
 150          * slices as there are buffer swaps scheduled in order to avoid tearing
 151          * (based on the assumption that a single buffer swap would always
 152          * complete before scanout starts).
 153          */
 154         for (i = 0; i++ < nhits;
 155              upper[0] = lower[0], lower[0] += slice[0],
 156              upper[1] = lower[1], lower[1] += slice[1]) {
 157                 if (i == nhits)
 158                         lower[0] = lower[1] = sarea_priv->height;
 159
 160                 list_for_each(hit, &hits) {
 161                         drm_i915_vbl_swap_t *swap_hit =
 162                                 list_entry(hit, drm_i915_vbl_swap_t, head);
 163                         drm_clip_rect_t *rect;
 164                         int num_rects, pipe;
 165                         unsigned short top, bottom;
 166
 167                         drw = drm_get_drawable_info(dev, swap_hit->drw_id);
 168
 169                         if (!drw)
 170                                 continue;
 171
 172                         rect = drw->rects;
 173                         pipe = swap_hit->pipe;
 174                         top = upper[pipe];
 175                         bottom = lower[pipe];
 176
 177                         for (num_rects = drw->num_rects; num_rects--; rect++) {
 178                                 int y1 = max(rect->y1, top);
 179                                 int y2 = min(rect->y2, bottom);
 180
 181                                 if (y1 >= y2)
 182                                         continue;
 183
 184                                 BEGIN_LP_RING(8);
 185
 186                                 OUT_RING(cmd);
 187                                 OUT_RING(pitchropcpp);
 188                                 OUT_RING((y1 << 16) | rect->x1);
 189                                 OUT_RING((y2 << 16) | rect->x2);
 190                                 OUT_RING(sarea_priv->front_offset);
 191                                 OUT_RING((y1 << 16) | rect->x1);
 192                                 OUT_RING(pitchropcpp & 0xffff);
 193                                 OUT_RING(sarea_priv->back_offset);
 194
 195                                 ADVANCE_LP_RING();
 196                         }
 197                 }
 198         }
 199
 200         spin_unlock_irqrestore(&dev->drw_lock, irqflags);
 201
 202         list_for_each_safe(hit, tmp, &hits) {
 203                 drm_i915_vbl_swap_t *swap_hit =
 204                         list_entry(hit, drm_i915_vbl_swap_t, head);
 205
 206                 list_del(hit);
 207
 208                 drm_free(swap_hit, sizeof(*swap_hit), DRM_MEM_DRIVER);
 209         }
 210 }
 211
 212 irqreturn_t i915_driver_irq_handler(DRM_IRQ_ARGS)
 213 {
 214         drm_device_t *dev = (drm_device_t *) arg;
 215         drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
 216         u16 temp;
 217
 218         temp = I915_READ16(I915REG_INT_IDENTITY_R);
 219
 220         temp &= (USER_INT_FLAG | VSYNC_PIPEA_FLAG | VSYNC_PIPEB_FLAG);
 221
 222         DRM_DEBUG("%s flag=%08x\n", __FUNCTION__, temp);
 223
 224         if (temp == 0)
 225                 return IRQ_NONE;
 226
 227         I915_WRITE16(I915REG_INT_IDENTITY_R, temp);
 228
 229         dev_priv->sarea_priv->last_dispatch = READ_BREADCRUMB(dev_priv);
 230
 231         if (temp & USER_INT_FLAG)
 232                 DRM_WAKEUP(&dev_priv->irq_queue);
 233
 234         if (temp & (VSYNC_PIPEA_FLAG | VSYNC_PIPEB_FLAG)) {
 235                 int vblank_pipe = dev_priv->vblank_pipe;
 236
 237                 if ((vblank_pipe &
 238                      (DRM_I915_VBLANK_PIPE_A | DRM_I915_VBLANK_PIPE_B))
 239                     == (DRM_I915_VBLANK_PIPE_A | DRM_I915_VBLANK_PIPE_B)) {
 240                         if (temp & VSYNC_PIPEA_FLAG)
 241                                 atomic_inc(&dev->vbl_received);
 242                         if (temp & VSYNC_PIPEB_FLAG)
 243                                 atomic_inc(&dev->vbl_received2);
 244                 } else if (((temp & VSYNC_PIPEA_FLAG) &&
 245                             (vblank_pipe & DRM_I915_VBLANK_PIPE_A)) ||
 246                            ((temp & VSYNC_PIPEB_FLAG) &&
 247                             (vblank_pipe & DRM_I915_VBLANK_PIPE_B)))
 248                         atomic_inc(&dev->vbl_received);
 249
 250                 DRM_WAKEUP(&dev->vbl_queue);
 251                 drm_vbl_send_signals(dev);
 252
 253                 if (dev_priv->swaps_pending > 0)
 254                         drm_locked_tasklet(dev, i915_vblank_tasklet);
 255         }
 256
 257         return IRQ_HANDLED;
 258 }
 259
 260 static int i915_emit_irq(drm_device_t * dev)
 261 {
 262         drm_i915_private_t *dev_priv = dev->dev_private;
 263         RING_LOCALS;
 264
 265         i915_kernel_lost_context(dev);
 266
 267         DRM_DEBUG("%s\n", __FUNCTION__);
 268
 269         dev_priv->sarea_priv->last_enqueue = ++dev_priv->counter;
 270
 271         if (dev_priv->counter > 0x7FFFFFFFUL)
 272                 dev_priv->sarea_priv->last_enqueue = dev_priv->counter = 1;
 273
 274         BEGIN_LP_RING(6);
 275         OUT_RING(CMD_STORE_DWORD_IDX);
 276         OUT_RING(20);
 277         OUT_RING(dev_priv->counter);
 278         OUT_RING(0);
 279         OUT_RING(0);
 280         OUT_RING(GFX_OP_USER_INTERRUPT);
 281         ADVANCE_LP_RING();
 282
 283         return dev_priv->counter;
 284 }
 285
 286 static int i915_wait_irq(drm_device_t * dev, int irq_nr)
 287 {
 288         drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
 289         int ret = 0;
 290
 291         DRM_DEBUG("%s irq_nr=%d breadcrumb=%d\n", __FUNCTION__, irq_nr,
 292                   READ_BREADCRUMB(dev_priv));
 293
 294         if (READ_BREADCRUMB(dev_priv) >= irq_nr)
 295                 return 0;
 296
 297         dev_priv->sarea_priv->perf_boxes |= I915_BOX_WAIT;
 298
 299         DRM_WAIT_ON(ret, dev_priv->irq_queue, 3 * DRM_HZ,
 300                     READ_BREADCRUMB(dev_priv) >= irq_nr);
 301
 302         if (ret == DRM_ERR(EBUSY)) {
 303                 DRM_ERROR("%s: EBUSY -- rec: %d emitted: %d\n",
 304                           __FUNCTION__,
 305                           READ_BREADCRUMB(dev_priv), (int)dev_priv->counter);
 306         }
 307
 308         dev_priv->sarea_priv->last_dispatch = READ_BREADCRUMB(dev_priv);
 309         return ret;
 310 }
 311
 312 static int i915_driver_vblank_do_wait(drm_device_t *dev, unsigned int *sequence,
 313                                       atomic_t *counter)
 314 {
 315         drm_i915_private_t *dev_priv = dev->dev_private;
 316         unsigned int cur_vblank;
 317         int ret = 0;
 318
 319         if (!dev_priv) {
 320                 DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
 321                 return DRM_ERR(EINVAL);
 322         }
 323
 324         DRM_WAIT_ON(ret, dev->vbl_queue, 3 * DRM_HZ,
 325                     (((cur_vblank = atomic_read(counter))
 326                         - *sequence) <= (1<<23)));
 327
 328         *sequence = cur_vblank;
 329
 330         return ret;
 331 }
 332
 333
 334 int i915_driver_vblank_wait(drm_device_t *dev, unsigned int *sequence)
 335 {
 336         return i915_driver_vblank_do_wait(dev, sequence, &dev->vbl_received);
 337 }
 338
 339 int i915_driver_vblank_wait2(drm_device_t *dev, unsigned int *sequence)
 340 {
 341         return i915_driver_vblank_do_wait(dev, sequence, &dev->vbl_received2);
 342 }
 343
 344 /* Needs the lock as it touches the ring.
 345  */
 346 int i915_irq_emit(DRM_IOCTL_ARGS)
 347 {
 348         DRM_DEVICE;
 349         drm_i915_private_t *dev_priv = dev->dev_private;
 350         drm_i915_irq_emit_t emit;
 351         int result;
 352
 353         LOCK_TEST_WITH_RETURN(dev, filp);
 354
 355         if (!dev_priv) {
 356                 DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
 357                 return DRM_ERR(EINVAL);
 358         }
 359
 360         DRM_COPY_FROM_USER_IOCTL(emit, (drm_i915_irq_emit_t __user *) data,
 361                                  sizeof(emit));
 362
 363         result = i915_emit_irq(dev);
 364
 365         if (DRM_COPY_TO_USER(emit.irq_seq, &result, sizeof(int))) {
 366                 DRM_ERROR("copy_to_user\n");
 367                 return DRM_ERR(EFAULT);
 368         }
 369
 370         return 0;
 371 }
 372
 373 /* Doesn't need the hardware lock.
 374  */
 375 int i915_irq_wait(DRM_IOCTL_ARGS)
 376 {
 377         DRM_DEVICE;
 378         drm_i915_private_t *dev_priv = dev->dev_private;
 379         drm_i915_irq_wait_t irqwait;
 380
 381         if (!dev_priv) {
 382                 DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
 383                 return DRM_ERR(EINVAL);
 384         }
 385
 386         DRM_COPY_FROM_USER_IOCTL(irqwait, (drm_i915_irq_wait_t __user *) data,
 387                                  sizeof(irqwait));
 388
 389         return i915_wait_irq(dev, irqwait.irq_seq);
 390 }
 391
 392 static void i915_enable_interrupt (drm_device_t *dev)
 393 {
 394         drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
 395         u16 flag;
 396
 397         flag = 0;
 398         if (dev_priv->vblank_pipe & DRM_I915_VBLANK_PIPE_A)
 399                 flag |= VSYNC_PIPEA_FLAG;
 400         if (dev_priv->vblank_pipe & DRM_I915_VBLANK_PIPE_B)
 401                 flag |= VSYNC_PIPEB_FLAG;
 402
 403         I915_WRITE16(I915REG_INT_ENABLE_R, USER_INT_FLAG | flag);
 404 }
 405
 406 /* Set the vblank monitor pipe
 407  */
 408 int i915_vblank_pipe_set(DRM_IOCTL_ARGS)
 409 {
 410         DRM_DEVICE;
 411         drm_i915_private_t *dev_priv = dev->dev_private;
 412         drm_i915_vblank_pipe_t pipe;
 413
 414         if (!dev_priv) {
 415                 DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
 416                 return DRM_ERR(EINVAL);
 417         }
 418
 419         DRM_COPY_FROM_USER_IOCTL(pipe, (drm_i915_vblank_pipe_t __user *) data,
 420                                  sizeof(pipe));
 421
 422         if (pipe.pipe & ~(DRM_I915_VBLANK_PIPE_A|DRM_I915_VBLANK_PIPE_B)) {
 423                 DRM_ERROR("%s called with invalid pipe 0x%x\n",
 424                           __FUNCTION__, pipe.pipe);
 425                 return DRM_ERR(EINVAL);
 426         }
 427
 428         dev_priv->vblank_pipe = pipe.pipe;
 429
 430         i915_enable_interrupt (dev);
 431
 432         return 0;
 433 }
 434
 435 int i915_vblank_pipe_get(DRM_IOCTL_ARGS)
 436 {
 437         DRM_DEVICE;
 438         drm_i915_private_t *dev_priv = dev->dev_private;
 439         drm_i915_vblank_pipe_t pipe;
 440         u16 flag;
 441
 442         if (!dev_priv) {
 443                 DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
 444                 return DRM_ERR(EINVAL);
 445         }
 446
 447         flag = I915_READ(I915REG_INT_ENABLE_R);
 448         pipe.pipe = 0;
 449         if (flag & VSYNC_PIPEA_FLAG)
 450                 pipe.pipe |= DRM_I915_VBLANK_PIPE_A;
 451         if (flag & VSYNC_PIPEB_FLAG)
 452                 pipe.pipe |= DRM_I915_VBLANK_PIPE_B;
 453         DRM_COPY_TO_USER_IOCTL((drm_i915_vblank_pipe_t __user *) data, pipe,
 454                                  sizeof(pipe));
 455         return 0;
 456 }
 457
 458 /**
 459  * Schedule buffer swap at given vertical blank.
 460  */
 461 int i915_vblank_swap(DRM_IOCTL_ARGS)
 462 {
 463         DRM_DEVICE;
 464         drm_i915_private_t *dev_priv = dev->dev_private;
 465         drm_i915_vblank_swap_t swap;
 466         drm_i915_vbl_swap_t *vbl_swap;
 467         unsigned int pipe, seqtype, curseq;
 468         unsigned long irqflags;
 469         struct list_head *list;
 470
 471         if (!dev_priv) {
 472                 DRM_ERROR("%s called with no initialization\n", __func__);
 473                 return DRM_ERR(EINVAL);
 474         }
 475
 476         if (dev_priv->sarea_priv->rotation) {
 477                 DRM_DEBUG("Rotation not supported\n");
 478                 return DRM_ERR(EINVAL);
 479         }
 480
 481         DRM_COPY_FROM_USER_IOCTL(swap, (drm_i915_vblank_swap_t __user *) data,
 482                                  sizeof(swap));
 483
 484         if (swap.seqtype & ~(_DRM_VBLANK_RELATIVE | _DRM_VBLANK_ABSOLUTE |
 485                              _DRM_VBLANK_SECONDARY | _DRM_VBLANK_NEXTONMISS)) {
 486                 DRM_ERROR("Invalid sequence type 0x%x\n", swap.seqtype);
 487                 return DRM_ERR(EINVAL);
 488         }
 489
 490         pipe = (swap.seqtype & _DRM_VBLANK_SECONDARY) ? 1 : 0;
 491
 492         seqtype = swap.seqtype & (_DRM_VBLANK_RELATIVE | _DRM_VBLANK_ABSOLUTE);
 493
 494         if (!(dev_priv->vblank_pipe & (1 << pipe))) {
 495                 DRM_ERROR("Invalid pipe %d\n", pipe);
 496                 return DRM_ERR(EINVAL);
 497         }
 498
 499         spin_lock_irqsave(&dev->drw_lock, irqflags);
 500
 501         if (!drm_get_drawable_info(dev, swap.drawable)) {
 502                 spin_unlock_irqrestore(&dev->drw_lock, irqflags);
 503                 DRM_ERROR("Invalid drawable ID %d\n", swap.drawable);
 504                 return DRM_ERR(EINVAL);
 505         }
 506
 507         spin_unlock_irqrestore(&dev->drw_lock, irqflags);
 508
 509         curseq = atomic_read(pipe ? &dev->vbl_received2 : &dev->vbl_received);
 510
 511         if (seqtype == _DRM_VBLANK_RELATIVE)
 512                 swap.sequence += curseq;
 513
 514         if ((curseq - swap.sequence) <= (1<<23)) {
 515                 if (swap.seqtype & _DRM_VBLANK_NEXTONMISS) {
 516                         swap.sequence = curseq + 1;
 517                 } else {
 518                         DRM_DEBUG("Missed target sequence\n");
 519                         return DRM_ERR(EINVAL);
 520                 }
 521         }
 522
 523         spin_lock_irqsave(&dev_priv->swaps_lock, irqflags);
 524
 525         list_for_each(list, &dev_priv->vbl_swaps.head) {
 526                 vbl_swap = list_entry(list, drm_i915_vbl_swap_t, head);
 527
 528                 if (vbl_swap->drw_id == swap.drawable &&
 529                     vbl_swap->pipe == pipe &&
 530                     vbl_swap->sequence == swap.sequence) {
 531                         spin_unlock_irqrestore(&dev_priv->swaps_lock, irqflags);
 532                         DRM_DEBUG("Already scheduled\n");
 533                         return 0;
 534                 }
 535         }
 536
 537         spin_unlock_irqrestore(&dev_priv->swaps_lock, irqflags);
 538
 539         if (dev_priv->swaps_pending >= 100) {
 540                 DRM_DEBUG("Too many swaps queued\n");
 541                 return DRM_ERR(EBUSY);
 542         }
 543
 544         vbl_swap = drm_calloc(1, sizeof(vbl_swap), DRM_MEM_DRIVER);
 545
 546         if (!vbl_swap) {
 547                 DRM_ERROR("Failed to allocate memory to queue swap\n");
 548                 return DRM_ERR(ENOMEM);
 549         }
 550
 551         DRM_DEBUG("\n");
 552
 553         vbl_swap->drw_id = swap.drawable;
 554         vbl_swap->pipe = pipe;
 555         vbl_swap->sequence = swap.sequence;
 556
 557         spin_lock_irqsave(&dev_priv->swaps_lock, irqflags);
 558
 559         list_add_tail((struct list_head *)vbl_swap, &dev_priv->vbl_swaps.head);
 560         dev_priv->swaps_pending++;
 561
 562         spin_unlock_irqrestore(&dev_priv->swaps_lock, irqflags);
 563
 564         DRM_COPY_TO_USER_IOCTL((drm_i915_vblank_swap_t __user *) data, swap,
 565                                sizeof(swap));
 566
 567         return 0;
 568 }
 569
 570 /* drm_dma.h hooks
 571 */
 572 void i915_driver_irq_preinstall(drm_device_t * dev)
 573 {
 574         drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
 575
 576         I915_WRITE16(I915REG_HWSTAM, 0xfffe);
 577         I915_WRITE16(I915REG_INT_MASK_R, 0x0);
 578         I915_WRITE16(I915REG_INT_ENABLE_R, 0x0);
 579 }
 580
 581 void i915_driver_irq_postinstall(drm_device_t * dev)
 582 {
 583         drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
 584
 585         dev_priv->swaps_lock = SPIN_LOCK_UNLOCKED;
 586         INIT_LIST_HEAD(&dev_priv->vbl_swaps.head);
 587         dev_priv->swaps_pending = 0;
 588
 589         if (!dev_priv->vblank_pipe)
 590                 dev_priv->vblank_pipe = DRM_I915_VBLANK_PIPE_A;
 591         i915_enable_interrupt(dev);
 592         DRM_INIT_WAITQUEUE(&dev_priv->irq_queue);
 593 }
 594
 595 void i915_driver_irq_uninstall(drm_device_t * dev)
 596 {
 597         drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
 598         u16 temp;
 599
 600         if (!dev_priv)
 601                 return;
 602
 603         I915_WRITE16(I915REG_HWSTAM, 0xffff);
 604         I915_WRITE16(I915REG_INT_MASK_R, 0xffff);
 605         I915_WRITE16(I915REG_INT_ENABLE_R, 0x0);
 606
 607         temp = I915_READ16(I915REG_INT_IDENTITY_R);
 608         I915_WRITE16(I915REG_INT_IDENTITY_R, temp);
 609 }