git.oblomov.eu Git - linux-2.6/blob - drivers/gpu/drm/ttm/ttm_bo_util.c

   1 /**************************************************************************
   2  *
   3  * Copyright (c) 2007-2009 VMware, Inc., Palo Alto, CA., USA
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the
   8  * "Software"), to deal in the Software without restriction, including
   9  * without limitation the rights to use, copy, modify, merge, publish,
  10  * distribute, sub license, and/or sell copies of the Software, and to
  11  * permit persons to whom the Software is furnished to do so, subject to
  12  * the following conditions:
  13  *
  14  * The above copyright notice and this permission notice (including the
  15  * next paragraph) shall be included in all copies or substantial portions
  16  * of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
  21  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
  22  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  23  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  24  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  **************************************************************************/
  27 /*
  28  * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
  29  */
  30
  31 #include "ttm/ttm_bo_driver.h"
  32 #include "ttm/ttm_placement.h"
  33 #include <linux/io.h>
  34 #include <linux/highmem.h>
  35 #include <linux/wait.h>
  36 #include <linux/vmalloc.h>
  37 #include <linux/module.h>
  38
  39 void ttm_bo_free_old_node(struct ttm_buffer_object *bo)
  40 {
  41         struct ttm_mem_reg *old_mem = &bo->mem;
  42
  43         if (old_mem->mm_node) {
  44                 spin_lock(&bo->bdev->lru_lock);
  45                 drm_mm_put_block(old_mem->mm_node);
  46                 spin_unlock(&bo->bdev->lru_lock);
  47         }
  48         old_mem->mm_node = NULL;
  49 }
  50
  51 int ttm_bo_move_ttm(struct ttm_buffer_object *bo,
  52                     bool evict, bool no_wait, struct ttm_mem_reg *new_mem)
  53 {
  54         struct ttm_tt *ttm = bo->ttm;
  55         struct ttm_mem_reg *old_mem = &bo->mem;
  56         uint32_t save_flags = old_mem->placement;
  57         int ret;
  58
  59         if (old_mem->mem_type != TTM_PL_SYSTEM) {
  60                 ttm_tt_unbind(ttm);
  61                 ttm_bo_free_old_node(bo);
  62                 ttm_flag_masked(&old_mem->placement, TTM_PL_FLAG_SYSTEM,
  63                                 TTM_PL_MASK_MEM);
  64                 old_mem->mem_type = TTM_PL_SYSTEM;
  65                 save_flags = old_mem->placement;
  66         }
  67
  68         ret = ttm_tt_set_placement_caching(ttm, new_mem->placement);
  69         if (unlikely(ret != 0))
  70                 return ret;
  71
  72         if (new_mem->mem_type != TTM_PL_SYSTEM) {
  73                 ret = ttm_tt_bind(ttm, new_mem);
  74                 if (unlikely(ret != 0))
  75                         return ret;
  76         }
  77
  78         *old_mem = *new_mem;
  79         new_mem->mm_node = NULL;
  80         ttm_flag_masked(&save_flags, new_mem->placement, TTM_PL_MASK_MEMTYPE);
  81         return 0;
  82 }
  83 EXPORT_SYMBOL(ttm_bo_move_ttm);
  84
  85 int ttm_mem_reg_ioremap(struct ttm_bo_device *bdev, struct ttm_mem_reg *mem,
  86                         void **virtual)
  87 {
  88         struct ttm_mem_type_manager *man = &bdev->man[mem->mem_type];
  89         unsigned long bus_offset;
  90         unsigned long bus_size;
  91         unsigned long bus_base;
  92         int ret;
  93         void *addr;
  94
  95         *virtual = NULL;
  96         ret = ttm_bo_pci_offset(bdev, mem, &bus_base, &bus_offset, &bus_size);
  97         if (ret || bus_size == 0)
  98                 return ret;
  99
 100         if (!(man->flags & TTM_MEMTYPE_FLAG_NEEDS_IOREMAP))
 101                 addr = (void *)(((u8 *) man->io_addr) + bus_offset);
 102         else {
 103                 if (mem->placement & TTM_PL_FLAG_WC)
 104                         addr = ioremap_wc(bus_base + bus_offset, bus_size);
 105                 else
 106                         addr = ioremap_nocache(bus_base + bus_offset, bus_size);
 107                 if (!addr)
 108                         return -ENOMEM;
 109         }
 110         *virtual = addr;
 111         return 0;
 112 }
 113
 114 void ttm_mem_reg_iounmap(struct ttm_bo_device *bdev, struct ttm_mem_reg *mem,
 115                          void *virtual)
 116 {
 117         struct ttm_mem_type_manager *man;
 118
 119         man = &bdev->man[mem->mem_type];
 120
 121         if (virtual && (man->flags & TTM_MEMTYPE_FLAG_NEEDS_IOREMAP))
 122                 iounmap(virtual);
 123 }
 124
 125 static int ttm_copy_io_page(void *dst, void *src, unsigned long page)
 126 {
 127         uint32_t *dstP =
 128             (uint32_t *) ((unsigned long)dst + (page << PAGE_SHIFT));
 129         uint32_t *srcP =
 130             (uint32_t *) ((unsigned long)src + (page << PAGE_SHIFT));
 131
 132         int i;
 133         for (i = 0; i < PAGE_SIZE / sizeof(uint32_t); ++i)
 134                 iowrite32(ioread32(srcP++), dstP++);
 135         return 0;
 136 }
 137
 138 static int ttm_copy_io_ttm_page(struct ttm_tt *ttm, void *src,
 139                                 unsigned long page,
 140                                 pgprot_t prot)
 141 {
 142         struct page *d = ttm_tt_get_page(ttm, page);
 143         void *dst;
 144
 145         if (!d)
 146                 return -ENOMEM;
 147
 148         src = (void *)((unsigned long)src + (page << PAGE_SHIFT));
 149
 150 #ifdef CONFIG_X86
 151         dst = kmap_atomic_prot(d, KM_USER0, prot);
 152 #else
 153         if (pgprot_val(prot) != pgprot_val(PAGE_KERNEL))
 154                 dst = vmap(&d, 1, 0, prot);
 155         else
 156                 dst = kmap(d);
 157 #endif
 158         if (!dst)
 159                 return -ENOMEM;
 160
 161         memcpy_fromio(dst, src, PAGE_SIZE);
 162
 163 #ifdef CONFIG_X86
 164         kunmap_atomic(dst, KM_USER0);
 165 #else
 166         if (pgprot_val(prot) != pgprot_val(PAGE_KERNEL))
 167                 vunmap(dst);
 168         else
 169                 kunmap(d);
 170 #endif
 171
 172         return 0;
 173 }
 174
 175 static int ttm_copy_ttm_io_page(struct ttm_tt *ttm, void *dst,
 176                                 unsigned long page,
 177                                 pgprot_t prot)
 178 {
 179         struct page *s = ttm_tt_get_page(ttm, page);
 180         void *src;
 181
 182         if (!s)
 183                 return -ENOMEM;
 184
 185         dst = (void *)((unsigned long)dst + (page << PAGE_SHIFT));
 186 #ifdef CONFIG_X86
 187         src = kmap_atomic_prot(s, KM_USER0, prot);
 188 #else
 189         if (pgprot_val(prot) != pgprot_val(PAGE_KERNEL))
 190                 src = vmap(&s, 1, 0, prot);
 191         else
 192                 src = kmap(s);
 193 #endif
 194         if (!src)
 195                 return -ENOMEM;
 196
 197         memcpy_toio(dst, src, PAGE_SIZE);
 198
 199 #ifdef CONFIG_X86
 200         kunmap_atomic(src, KM_USER0);
 201 #else
 202         if (pgprot_val(prot) != pgprot_val(PAGE_KERNEL))
 203                 vunmap(src);
 204         else
 205                 kunmap(s);
 206 #endif
 207
 208         return 0;
 209 }
 210
 211 int ttm_bo_move_memcpy(struct ttm_buffer_object *bo,
 212                        bool evict, bool no_wait, struct ttm_mem_reg *new_mem)
 213 {
 214         struct ttm_bo_device *bdev = bo->bdev;
 215         struct ttm_mem_type_manager *man = &bdev->man[new_mem->mem_type];
 216         struct ttm_tt *ttm = bo->ttm;
 217         struct ttm_mem_reg *old_mem = &bo->mem;
 218         struct ttm_mem_reg old_copy = *old_mem;
 219         void *old_iomap;
 220         void *new_iomap;
 221         int ret;
 222         uint32_t save_flags = old_mem->placement;
 223         unsigned long i;
 224         unsigned long page;
 225         unsigned long add = 0;
 226         int dir;
 227
 228         ret = ttm_mem_reg_ioremap(bdev, old_mem, &old_iomap);
 229         if (ret)
 230                 return ret;
 231         ret = ttm_mem_reg_ioremap(bdev, new_mem, &new_iomap);
 232         if (ret)
 233                 goto out;
 234
 235         if (old_iomap == NULL && new_iomap == NULL)
 236                 goto out2;
 237         if (old_iomap == NULL && ttm == NULL)
 238                 goto out2;
 239
 240         add = 0;
 241         dir = 1;
 242
 243         if ((old_mem->mem_type == new_mem->mem_type) &&
 244             (new_mem->mm_node->start <
 245              old_mem->mm_node->start + old_mem->mm_node->size)) {
 246                 dir = -1;
 247                 add = new_mem->num_pages - 1;
 248         }
 249
 250         for (i = 0; i < new_mem->num_pages; ++i) {
 251                 page = i * dir + add;
 252                 if (old_iomap == NULL) {
 253                         pgprot_t prot = ttm_io_prot(old_mem->placement,
 254                                                     PAGE_KERNEL);
 255                         ret = ttm_copy_ttm_io_page(ttm, new_iomap, page,
 256                                                    prot);
 257                 } else if (new_iomap == NULL) {
 258                         pgprot_t prot = ttm_io_prot(new_mem->placement,
 259                                                     PAGE_KERNEL);
 260                         ret = ttm_copy_io_ttm_page(ttm, old_iomap, page,
 261                                                    prot);
 262                 } else
 263                         ret = ttm_copy_io_page(new_iomap, old_iomap, page);
 264                 if (ret)
 265                         goto out1;
 266         }
 267         mb();
 268 out2:
 269         ttm_bo_free_old_node(bo);
 270
 271         *old_mem = *new_mem;
 272         new_mem->mm_node = NULL;
 273         ttm_flag_masked(&save_flags, new_mem->placement, TTM_PL_MASK_MEMTYPE);
 274
 275         if ((man->flags & TTM_MEMTYPE_FLAG_FIXED) && (ttm != NULL)) {
 276                 ttm_tt_unbind(ttm);
 277                 ttm_tt_destroy(ttm);
 278                 bo->ttm = NULL;
 279         }
 280
 281 out1:
 282         ttm_mem_reg_iounmap(bdev, new_mem, new_iomap);
 283 out:
 284         ttm_mem_reg_iounmap(bdev, &old_copy, old_iomap);
 285         return ret;
 286 }
 287 EXPORT_SYMBOL(ttm_bo_move_memcpy);
 288
 289 static void ttm_transfered_destroy(struct ttm_buffer_object *bo)
 290 {
 291         kfree(bo);
 292 }
 293
 294 /**
 295  * ttm_buffer_object_transfer
 296  *
 297  * @bo: A pointer to a struct ttm_buffer_object.
 298  * @new_obj: A pointer to a pointer to a newly created ttm_buffer_object,
 299  * holding the data of @bo with the old placement.
 300  *
 301  * This is a utility function that may be called after an accelerated move
 302  * has been scheduled. A new buffer object is created as a placeholder for
 303  * the old data while it's being copied. When that buffer object is idle,
 304  * it can be destroyed, releasing the space of the old placement.
 305  * Returns:
 306  * !0: Failure.
 307  */
 308
 309 static int ttm_buffer_object_transfer(struct ttm_buffer_object *bo,
 310                                       struct ttm_buffer_object **new_obj)
 311 {
 312         struct ttm_buffer_object *fbo;
 313         struct ttm_bo_device *bdev = bo->bdev;
 314         struct ttm_bo_driver *driver = bdev->driver;
 315
 316         fbo = kzalloc(sizeof(*fbo), GFP_KERNEL);
 317         if (!fbo)
 318                 return -ENOMEM;
 319
 320         *fbo = *bo;
 321
 322         /**
 323          * Fix up members that we shouldn't copy directly:
 324          * TODO: Explicit member copy would probably be better here.
 325          */
 326
 327         spin_lock_init(&fbo->lock);
 328         init_waitqueue_head(&fbo->event_queue);
 329         INIT_LIST_HEAD(&fbo->ddestroy);
 330         INIT_LIST_HEAD(&fbo->lru);
 331         INIT_LIST_HEAD(&fbo->swap);
 332         fbo->vm_node = NULL;
 333
 334         fbo->sync_obj = driver->sync_obj_ref(bo->sync_obj);
 335         if (fbo->mem.mm_node)
 336                 fbo->mem.mm_node->private = (void *)fbo;
 337         kref_init(&fbo->list_kref);
 338         kref_init(&fbo->kref);
 339         fbo->destroy = &ttm_transfered_destroy;
 340
 341         *new_obj = fbo;
 342         return 0;
 343 }
 344
 345 pgprot_t ttm_io_prot(uint32_t caching_flags, pgprot_t tmp)
 346 {
 347 #if defined(__i386__) || defined(__x86_64__)
 348         if (caching_flags & TTM_PL_FLAG_WC)
 349                 tmp = pgprot_writecombine(tmp);
 350         else if (boot_cpu_data.x86 > 3)
 351                 tmp = pgprot_noncached(tmp);
 352
 353 #elif defined(__powerpc__)
 354         if (!(caching_flags & TTM_PL_FLAG_CACHED)) {
 355                 pgprot_val(tmp) |= _PAGE_NO_CACHE;
 356                 if (caching_flags & TTM_PL_FLAG_UNCACHED)
 357                         pgprot_val(tmp) |= _PAGE_GUARDED;
 358         }
 359 #endif
 360 #if defined(__ia64__)
 361         if (caching_flags & TTM_PL_FLAG_WC)
 362                 tmp = pgprot_writecombine(tmp);
 363         else
 364                 tmp = pgprot_noncached(tmp);
 365 #endif
 366 #if defined(__sparc__)
 367         if (!(caching_flags & TTM_PL_FLAG_CACHED))
 368                 tmp = pgprot_noncached(tmp);
 369 #endif
 370         return tmp;
 371 }
 372
 373 static int ttm_bo_ioremap(struct ttm_buffer_object *bo,
 374                           unsigned long bus_base,
 375                           unsigned long bus_offset,
 376                           unsigned long bus_size,
 377                           struct ttm_bo_kmap_obj *map)
 378 {
 379         struct ttm_bo_device *bdev = bo->bdev;
 380         struct ttm_mem_reg *mem = &bo->mem;
 381         struct ttm_mem_type_manager *man = &bdev->man[mem->mem_type];
 382
 383         if (!(man->flags & TTM_MEMTYPE_FLAG_NEEDS_IOREMAP)) {
 384                 map->bo_kmap_type = ttm_bo_map_premapped;
 385                 map->virtual = (void *)(((u8 *) man->io_addr) + bus_offset);
 386         } else {
 387                 map->bo_kmap_type = ttm_bo_map_iomap;
 388                 if (mem->placement & TTM_PL_FLAG_WC)
 389                         map->virtual = ioremap_wc(bus_base + bus_offset,
 390                                                   bus_size);
 391                 else
 392                         map->virtual = ioremap_nocache(bus_base + bus_offset,
 393                                                        bus_size);
 394         }
 395         return (!map->virtual) ? -ENOMEM : 0;
 396 }
 397
 398 static int ttm_bo_kmap_ttm(struct ttm_buffer_object *bo,
 399                            unsigned long start_page,
 400                            unsigned long num_pages,
 401                            struct ttm_bo_kmap_obj *map)
 402 {
 403         struct ttm_mem_reg *mem = &bo->mem; pgprot_t prot;
 404         struct ttm_tt *ttm = bo->ttm;
 405         struct page *d;
 406         int i;
 407
 408         BUG_ON(!ttm);
 409         if (num_pages == 1 && (mem->placement & TTM_PL_FLAG_CACHED)) {
 410                 /*
 411                  * We're mapping a single page, and the desired
 412                  * page protection is consistent with the bo.
 413                  */
 414
 415                 map->bo_kmap_type = ttm_bo_map_kmap;
 416                 map->page = ttm_tt_get_page(ttm, start_page);
 417                 map->virtual = kmap(map->page);
 418         } else {
 419             /*
 420              * Populate the part we're mapping;
 421              */
 422                 for (i = start_page; i < start_page + num_pages; ++i) {
 423                         d = ttm_tt_get_page(ttm, i);
 424                         if (!d)
 425                                 return -ENOMEM;
 426                 }
 427
 428                 /*
 429                  * We need to use vmap to get the desired page protection
 430                  * or to make the buffer object look contigous.
 431                  */
 432                 prot = (mem->placement & TTM_PL_FLAG_CACHED) ?
 433                         PAGE_KERNEL :
 434                         ttm_io_prot(mem->placement, PAGE_KERNEL);
 435                 map->bo_kmap_type = ttm_bo_map_vmap;
 436                 map->virtual = vmap(ttm->pages + start_page, num_pages,
 437                                     0, prot);
 438         }
 439         return (!map->virtual) ? -ENOMEM : 0;
 440 }
 441
 442 int ttm_bo_kmap(struct ttm_buffer_object *bo,
 443                 unsigned long start_page, unsigned long num_pages,
 444                 struct ttm_bo_kmap_obj *map)
 445 {
 446         int ret;
 447         unsigned long bus_base;
 448         unsigned long bus_offset;
 449         unsigned long bus_size;
 450
 451         BUG_ON(!list_empty(&bo->swap));
 452         map->virtual = NULL;
 453         if (num_pages > bo->num_pages)
 454                 return -EINVAL;
 455         if (start_page > bo->num_pages)
 456                 return -EINVAL;
 457 #if 0
 458         if (num_pages > 1 && !DRM_SUSER(DRM_CURPROC))
 459                 return -EPERM;
 460 #endif
 461         ret = ttm_bo_pci_offset(bo->bdev, &bo->mem, &bus_base,
 462                                 &bus_offset, &bus_size);
 463         if (ret)
 464                 return ret;
 465         if (bus_size == 0) {
 466                 return ttm_bo_kmap_ttm(bo, start_page, num_pages, map);
 467         } else {
 468                 bus_offset += start_page << PAGE_SHIFT;
 469                 bus_size = num_pages << PAGE_SHIFT;
 470                 return ttm_bo_ioremap(bo, bus_base, bus_offset, bus_size, map);
 471         }
 472 }
 473 EXPORT_SYMBOL(ttm_bo_kmap);
 474
 475 void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map)
 476 {
 477         if (!map->virtual)
 478                 return;
 479         switch (map->bo_kmap_type) {
 480         case ttm_bo_map_iomap:
 481                 iounmap(map->virtual);
 482                 break;
 483         case ttm_bo_map_vmap:
 484                 vunmap(map->virtual);
 485                 break;
 486         case ttm_bo_map_kmap:
 487                 kunmap(map->page);
 488                 break;
 489         case ttm_bo_map_premapped:
 490                 break;
 491         default:
 492                 BUG();
 493         }
 494         map->virtual = NULL;
 495         map->page = NULL;
 496 }
 497 EXPORT_SYMBOL(ttm_bo_kunmap);
 498
 499 int ttm_bo_pfn_prot(struct ttm_buffer_object *bo,
 500                     unsigned long dst_offset,
 501                     unsigned long *pfn, pgprot_t *prot)
 502 {
 503         struct ttm_mem_reg *mem = &bo->mem;
 504         struct ttm_bo_device *bdev = bo->bdev;
 505         unsigned long bus_offset;
 506         unsigned long bus_size;
 507         unsigned long bus_base;
 508         int ret;
 509         ret = ttm_bo_pci_offset(bdev, mem, &bus_base, &bus_offset,
 510                         &bus_size);
 511         if (ret)
 512                 return -EINVAL;
 513         if (bus_size != 0)
 514                 *pfn = (bus_base + bus_offset + dst_offset) >> PAGE_SHIFT;
 515         else
 516                 if (!bo->ttm)
 517                         return -EINVAL;
 518                 else
 519                         *pfn = page_to_pfn(ttm_tt_get_page(bo->ttm,
 520                                                            dst_offset >>
 521                                                            PAGE_SHIFT));
 522         *prot = (mem->placement & TTM_PL_FLAG_CACHED) ?
 523                 PAGE_KERNEL : ttm_io_prot(mem->placement, PAGE_KERNEL);
 524
 525         return 0;
 526 }
 527
 528 int ttm_bo_move_accel_cleanup(struct ttm_buffer_object *bo,
 529                               void *sync_obj,
 530                               void *sync_obj_arg,
 531                               bool evict, bool no_wait,
 532                               struct ttm_mem_reg *new_mem)
 533 {
 534         struct ttm_bo_device *bdev = bo->bdev;
 535         struct ttm_bo_driver *driver = bdev->driver;
 536         struct ttm_mem_type_manager *man = &bdev->man[new_mem->mem_type];
 537         struct ttm_mem_reg *old_mem = &bo->mem;
 538         int ret;
 539         uint32_t save_flags = old_mem->placement;
 540         struct ttm_buffer_object *ghost_obj;
 541         void *tmp_obj = NULL;
 542
 543         spin_lock(&bo->lock);
 544         if (bo->sync_obj) {
 545                 tmp_obj = bo->sync_obj;
 546                 bo->sync_obj = NULL;
 547         }
 548         bo->sync_obj = driver->sync_obj_ref(sync_obj);
 549         bo->sync_obj_arg = sync_obj_arg;
 550         if (evict) {
 551                 ret = ttm_bo_wait(bo, false, false, false);
 552                 spin_unlock(&bo->lock);
 553                 if (tmp_obj)
 554                         driver->sync_obj_unref(&tmp_obj);
 555                 if (ret)
 556                         return ret;
 557
 558                 ttm_bo_free_old_node(bo);
 559                 if ((man->flags & TTM_MEMTYPE_FLAG_FIXED) &&
 560                     (bo->ttm != NULL)) {
 561                         ttm_tt_unbind(bo->ttm);
 562                         ttm_tt_destroy(bo->ttm);
 563                         bo->ttm = NULL;
 564                 }
 565         } else {
 566                 /**
 567                  * This should help pipeline ordinary buffer moves.
 568                  *
 569                  * Hang old buffer memory on a new buffer object,
 570                  * and leave it to be released when the GPU
 571                  * operation has completed.
 572                  */
 573
 574                 set_bit(TTM_BO_PRIV_FLAG_MOVING, &bo->priv_flags);
 575                 spin_unlock(&bo->lock);
 576                 if (tmp_obj)
 577                         driver->sync_obj_unref(&tmp_obj);
 578
 579                 ret = ttm_buffer_object_transfer(bo, &ghost_obj);
 580                 if (ret)
 581                         return ret;
 582
 583                 /**
 584                  * If we're not moving to fixed memory, the TTM object
 585                  * needs to stay alive. Otherwhise hang it on the ghost
 586                  * bo to be unbound and destroyed.
 587                  */
 588
 589                 if (!(man->flags & TTM_MEMTYPE_FLAG_FIXED))
 590                         ghost_obj->ttm = NULL;
 591                 else
 592                         bo->ttm = NULL;
 593
 594                 ttm_bo_unreserve(ghost_obj);
 595                 ttm_bo_unref(&ghost_obj);
 596         }
 597
 598         *old_mem = *new_mem;
 599         new_mem->mm_node = NULL;
 600         ttm_flag_masked(&save_flags, new_mem->placement, TTM_PL_MASK_MEMTYPE);
 601         return 0;
 602 }
 603 EXPORT_SYMBOL(ttm_bo_move_accel_cleanup);