drivers/gpu/drm/i915/i915_gem_stolen.c

   1 /*
   2  * Copyright © 2008-2012 Intel Corporation
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  21  * IN THE SOFTWARE.
  22  *
  23  * Authors:
  24  *    Eric Anholt <eric@anholt.net>
  25  *    Chris Wilson <chris@chris-wilson.co.uk>
  26  *
  27  */
  28
  29 #include <drm/drmP.h>
  30 #include <drm/i915_drm.h>
  31 #include "i915_drv.h"
  32
  33 /*
  34  * The BIOS typically reserves some of the system's memory for the exclusive
  35  * use of the integrated graphics. This memory is no longer available for
  36  * use by the OS and so the user finds that his system has less memory
  37  * available than he put in. We refer to this memory as stolen.
  38  *
  39  * The BIOS will allocate its framebuffer from the stolen memory. Our
  40  * goal is try to reuse that object for our own fbcon which must always
  41  * be available for panics. Anything else we can reuse the stolen memory
  42  * for is a boon.
  43  */
  44
  45 int i915_gem_stolen_insert_node_in_range(struct drm_i915_private *dev_priv,
  46                                          struct drm_mm_node *node, u64 size,
  47                                          unsigned alignment, u64 start, u64 end)
  48 {
  49         int ret;
  50
  51         if (!drm_mm_initialized(&dev_priv->mm.stolen))
  52                 return -ENODEV;
  53
  54         /* See the comment at the drm_mm_init() call for more about this check.
  55          * WaSkipStolenMemoryFirstPage:bdw,chv (incomplete) */
  56         if (INTEL_INFO(dev_priv)->gen == 8 && start < 4096)
  57                 start = 4096;
  58
  59         mutex_lock(&dev_priv->mm.stolen_lock);
  60         ret = drm_mm_insert_node_in_range(&dev_priv->mm.stolen, node, size,
  61                                           alignment, start, end,
  62                                           DRM_MM_SEARCH_DEFAULT);
  63         mutex_unlock(&dev_priv->mm.stolen_lock);
  64
  65         return ret;
  66 }
  67
  68 int i915_gem_stolen_insert_node(struct drm_i915_private *dev_priv,
  69                                 struct drm_mm_node *node, u64 size,
  70                                 unsigned alignment)
  71 {
  72         return i915_gem_stolen_insert_node_in_range(dev_priv, node, size,
  73                                         alignment, 0,
  74                                         dev_priv->gtt.stolen_usable_size);
  75 }
  76
  77 void i915_gem_stolen_remove_node(struct drm_i915_private *dev_priv,
  78                                  struct drm_mm_node *node)
  79 {
  80         mutex_lock(&dev_priv->mm.stolen_lock);
  81         drm_mm_remove_node(node);
  82         mutex_unlock(&dev_priv->mm.stolen_lock);
  83 }
  84
  85 static unsigned long i915_stolen_to_physical(struct drm_device *dev)
  86 {
  87         struct drm_i915_private *dev_priv = dev->dev_private;
  88         struct resource *r;
  89         u32 base;
  90
  91         /* Almost universally we can find the Graphics Base of Stolen Memory
  92          * at offset 0x5c in the igfx configuration space. On a few (desktop)
  93          * machines this is also mirrored in the bridge device at different
  94          * locations, or in the MCHBAR. On gen2, the layout is again slightly
  95          * different with the Graphics Segment immediately following Top of
  96          * Memory (or Top of Usable DRAM). Note it appears that TOUD is only
  97          * reported by 865g, so we just use the top of memory as determined
  98          * by the e820 probe.
  99          *
 100          * XXX However gen2 requires an unavailable symbol.
 101          */
 102         base = 0;
 103         if (INTEL_INFO(dev)->gen >= 3) {
 104                 /* Read Graphics Base of Stolen Memory directly */
 105                 pci_read_config_dword(dev->pdev, 0x5c, &base);
 106                 base &= ~((1<<20) - 1);
 107         } else { /* GEN2 */
 108 #if 0
 109                 /* Stolen is immediately above Top of Memory */
 110                 base = max_low_pfn_mapped << PAGE_SHIFT;
 111 #endif
 112         }
 113
 114         if (base == 0)
 115                 return 0;
 116
 117         /* make sure we don't clobber the GTT if it's within stolen memory */
 118         if (INTEL_INFO(dev)->gen <= 4 && !IS_G33(dev) && !IS_G4X(dev)) {
 119                 struct {
 120                         u32 start, end;
 121                 } stolen[2] = {
 122                         { .start = base, .end = base + dev_priv->gtt.stolen_size, },
 123                         { .start = base, .end = base + dev_priv->gtt.stolen_size, },
 124                 };
 125                 u64 gtt_start, gtt_end;
 126
 127                 gtt_start = I915_READ(PGTBL_CTL);
 128                 if (IS_GEN4(dev))
 129                         gtt_start = (gtt_start & PGTBL_ADDRESS_LO_MASK) |
 130                                 (gtt_start & PGTBL_ADDRESS_HI_MASK) << 28;
 131                 else
 132                         gtt_start &= PGTBL_ADDRESS_LO_MASK;
 133                 gtt_end = gtt_start + gtt_total_entries(dev_priv->gtt) * 4;
 134
 135                 if (gtt_start >= stolen[0].start && gtt_start < stolen[0].end)
 136                         stolen[0].end = gtt_start;
 137                 if (gtt_end > stolen[1].start && gtt_end <= stolen[1].end)
 138                         stolen[1].start = gtt_end;
 139
 140                 /* pick the larger of the two chunks */
 141                 if (stolen[0].end - stolen[0].start >
 142                     stolen[1].end - stolen[1].start) {
 143                         base = stolen[0].start;
 144                         dev_priv->gtt.stolen_size = stolen[0].end - stolen[0].start;
 145                 } else {
 146                         base = stolen[1].start;
 147                         dev_priv->gtt.stolen_size = stolen[1].end - stolen[1].start;
 148                 }
 149
 150                 if (stolen[0].start != stolen[1].start ||
 151                     stolen[0].end != stolen[1].end) {
 152                         DRM_DEBUG_KMS("GTT within stolen memory at 0x%llx-0x%llx\n",
 153                                       (unsigned long long) gtt_start,
 154                                       (unsigned long long) gtt_end - 1);
 155                         DRM_DEBUG_KMS("Stolen memory adjusted to 0x%x-0x%x\n",
 156                                       base, base + (u32) dev_priv->gtt.stolen_size - 1);
 157                 }
 158         }
 159
 160
 161         /* Verify that nothing else uses this physical address. Stolen
 162          * memory should be reserved by the BIOS and hidden from the
 163          * kernel. So if the region is already marked as busy, something
 164          * is seriously wrong.
 165          */
 166         r = devm_request_mem_region(dev->dev, base, dev_priv->gtt.stolen_size,
 167                                     "Graphics Stolen Memory");
 168         if (r == NULL) {
 169                 /*
 170                  * One more attempt but this time requesting region from
 171                  * base + 1, as we have seen that this resolves the region
 172                  * conflict with the PCI Bus.
 173                  * This is a BIOS w/a: Some BIOS wrap stolen in the root
 174                  * PCI bus, but have an off-by-one error. Hence retry the
 175                  * reservation starting from 1 instead of 0.
 176                  */
 177                 r = devm_request_mem_region(dev->dev, base + 1,
 178                                             dev_priv->gtt.stolen_size - 1,
 179                                             "Graphics Stolen Memory");
 180                 /*
 181                  * GEN3 firmware likes to smash pci bridges into the stolen
 182                  * range. Apparently this works.
 183                  */
 184                 if (r == NULL && !IS_GEN3(dev)) {
 185                         DRM_ERROR("conflict detected with stolen region: [0x%08x - 0x%08x]\n",
 186                                   base, base + (uint32_t)dev_priv->gtt.stolen_size);
 187                         base = 0;
 188                 }
 189         }
 190
 191         return base;
 192 }
 193
 194 void i915_gem_cleanup_stolen(struct drm_device *dev)
 195 {
 196         struct drm_i915_private *dev_priv = dev->dev_private;
 197
 198         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 199                 return;
 200
 201         drm_mm_takedown(&dev_priv->mm.stolen);
 202 }
 203
 204 static void g4x_get_stolen_reserved(struct drm_i915_private *dev_priv,
 205                                     unsigned long *base, unsigned long *size)
 206 {
 207         uint32_t reg_val = I915_READ(IS_GM45(dev_priv) ?
 208                                      CTG_STOLEN_RESERVED :
 209                                      ELK_STOLEN_RESERVED);
 210         unsigned long stolen_top = dev_priv->mm.stolen_base +
 211                 dev_priv->gtt.stolen_size;
 212
 213         *base = (reg_val & G4X_STOLEN_RESERVED_ADDR2_MASK) << 16;
 214
 215         WARN_ON((reg_val & G4X_STOLEN_RESERVED_ADDR1_MASK) < *base);
 216
 217         /* On these platforms, the register doesn't have a size field, so the
 218          * size is the distance between the base and the top of the stolen
 219          * memory. We also have the genuine case where base is zero and there's
 220          * nothing reserved. */
 221         if (*base == 0)
 222                 *size = 0;
 223         else
 224                 *size = stolen_top - *base;
 225 }
 226
 227 static void gen6_get_stolen_reserved(struct drm_i915_private *dev_priv,
 228                                      unsigned long *base, unsigned long *size)
 229 {
 230         uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
 231
 232         *base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
 233
 234         switch (reg_val & GEN6_STOLEN_RESERVED_SIZE_MASK) {
 235         case GEN6_STOLEN_RESERVED_1M:
 236                 *size = 1024 * 1024;
 237                 break;
 238         case GEN6_STOLEN_RESERVED_512K:
 239                 *size = 512 * 1024;
 240                 break;
 241         case GEN6_STOLEN_RESERVED_256K:
 242                 *size = 256 * 1024;
 243                 break;
 244         case GEN6_STOLEN_RESERVED_128K:
 245                 *size = 128 * 1024;
 246                 break;
 247         default:
 248                 *size = 1024 * 1024;
 249                 MISSING_CASE(reg_val & GEN6_STOLEN_RESERVED_SIZE_MASK);
 250         }
 251 }
 252
 253 static void gen7_get_stolen_reserved(struct drm_i915_private *dev_priv,
 254                                      unsigned long *base, unsigned long *size)
 255 {
 256         uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
 257
 258         *base = reg_val & GEN7_STOLEN_RESERVED_ADDR_MASK;
 259
 260         switch (reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK) {
 261         case GEN7_STOLEN_RESERVED_1M:
 262                 *size = 1024 * 1024;
 263                 break;
 264         case GEN7_STOLEN_RESERVED_256K:
 265                 *size = 256 * 1024;
 266                 break;
 267         default:
 268                 *size = 1024 * 1024;
 269                 MISSING_CASE(reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK);
 270         }
 271 }
 272
 273 static void gen8_get_stolen_reserved(struct drm_i915_private *dev_priv,
 274                                      unsigned long *base, unsigned long *size)
 275 {
 276         uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
 277
 278         *base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
 279
 280         switch (reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK) {
 281         case GEN8_STOLEN_RESERVED_1M:
 282                 *size = 1024 * 1024;
 283                 break;
 284         case GEN8_STOLEN_RESERVED_2M:
 285                 *size = 2 * 1024 * 1024;
 286                 break;
 287         case GEN8_STOLEN_RESERVED_4M:
 288                 *size = 4 * 1024 * 1024;
 289                 break;
 290         case GEN8_STOLEN_RESERVED_8M:
 291                 *size = 8 * 1024 * 1024;
 292                 break;
 293         default:
 294                 *size = 8 * 1024 * 1024;
 295                 MISSING_CASE(reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK);
 296         }
 297 }
 298
 299 static void bdw_get_stolen_reserved(struct drm_i915_private *dev_priv,
 300                                     unsigned long *base, unsigned long *size)
 301 {
 302         uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
 303         unsigned long stolen_top;
 304
 305         stolen_top = dev_priv->mm.stolen_base + dev_priv->gtt.stolen_size;
 306
 307         *base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
 308
 309         /* On these platforms, the register doesn't have a size field, so the
 310          * size is the distance between the base and the top of the stolen
 311          * memory. We also have the genuine case where base is zero and there's
 312          * nothing reserved. */
 313         if (*base == 0)
 314                 *size = 0;
 315         else
 316                 *size = stolen_top - *base;
 317 }
 318
 319 int i915_gem_init_stolen(struct drm_device *dev)
 320 {
 321         struct drm_i915_private *dev_priv = dev->dev_private;
 322         unsigned long reserved_total, reserved_base = 0, reserved_size;
 323         unsigned long stolen_top;
 324
 325         mutex_init(&dev_priv->mm.stolen_lock);
 326
 327 #ifdef CONFIG_INTEL_IOMMU
 328         if (intel_iommu_gfx_mapped && INTEL_INFO(dev)->gen < 8) {
 329                 DRM_INFO("DMAR active, disabling use of stolen memory\n");
 330                 return 0;
 331         }
 332 #endif
 333
 334         if (dev_priv->gtt.stolen_size == 0)
 335                 return 0;
 336
 337         dev_priv->mm.stolen_base = i915_stolen_to_physical(dev);
 338         if (dev_priv->mm.stolen_base == 0)
 339                 return 0;
 340
 341         stolen_top = dev_priv->mm.stolen_base + dev_priv->gtt.stolen_size;
 342
 343         switch (INTEL_INFO(dev_priv)->gen) {
 344         case 2:
 345         case 3:
 346                 break;
 347         case 4:
 348                 if (IS_G4X(dev))
 349                         g4x_get_stolen_reserved(dev_priv, &reserved_base,
 350                                                 &reserved_size);
 351                 break;
 352         case 5:
 353                 /* Assume the gen6 maximum for the older platforms. */
 354                 reserved_size = 1024 * 1024;
 355                 reserved_base = stolen_top - reserved_size;
 356                 break;
 357         case 6:
 358                 gen6_get_stolen_reserved(dev_priv, &reserved_base,
 359                                          &reserved_size);
 360                 break;
 361         case 7:
 362                 gen7_get_stolen_reserved(dev_priv, &reserved_base,
 363                                          &reserved_size);
 364                 break;
 365         default:
 366                 if (IS_BROADWELL(dev_priv) || IS_SKYLAKE(dev_priv))
 367                         bdw_get_stolen_reserved(dev_priv, &reserved_base,
 368                                                 &reserved_size);
 369                 else
 370                         gen8_get_stolen_reserved(dev_priv, &reserved_base,
 371                                                  &reserved_size);
 372                 break;
 373         }
 374
 375         /* It is possible for the reserved base to be zero, but the register
 376          * field for size doesn't have a zero option. */
 377         if (reserved_base == 0) {
 378                 reserved_size = 0;
 379                 reserved_base = stolen_top;
 380         }
 381
 382         if (reserved_base < dev_priv->mm.stolen_base ||
 383             reserved_base + reserved_size > stolen_top) {
 384                 DRM_DEBUG_KMS("Stolen reserved area [0x%08lx - 0x%08lx] outside stolen memory [0x%08lx - 0x%08lx]\n",
 385                               reserved_base, reserved_base + reserved_size,
 386                               dev_priv->mm.stolen_base, stolen_top);
 387                 return 0;
 388         }
 389
 390         /* It is possible for the reserved area to end before the end of stolen
 391          * memory, so just consider the start. */
 392         reserved_total = stolen_top - reserved_base;
 393
 394         DRM_DEBUG_KMS("Memory reserved for graphics device: %zuK, usable: %luK\n",
 395                       dev_priv->gtt.stolen_size >> 10,
 396                       (dev_priv->gtt.stolen_size - reserved_total) >> 10);
 397
 398         dev_priv->gtt.stolen_usable_size = dev_priv->gtt.stolen_size -
 399                                            reserved_total;
 400
 401         /*
 402          * Basic memrange allocator for stolen space.
 403          *
 404          * TODO: Notice that some platforms require us to not use the first page
 405          * of the stolen memory but their BIOSes may still put the framebuffer
 406          * on the first page. So we don't reserve this page for now because of
 407          * that. Our current solution is to just prevent new nodes from being
 408          * inserted on the first page - see the check we have at
 409          * i915_gem_stolen_insert_node_in_range(). We may want to fix the fbcon
 410          * problem later.
 411          */
 412         drm_mm_init(&dev_priv->mm.stolen, 0, dev_priv->gtt.stolen_usable_size);
 413
 414         return 0;
 415 }
 416
 417 static struct sg_table *
 418 i915_pages_create_for_stolen(struct drm_device *dev,
 419                              u32 offset, u32 size)
 420 {
 421         struct drm_i915_private *dev_priv = dev->dev_private;
 422         struct sg_table *st;
 423         struct scatterlist *sg;
 424
 425         DRM_DEBUG_DRIVER("offset=0x%x, size=%d\n", offset, size);
 426         BUG_ON(offset > dev_priv->gtt.stolen_size - size);
 427
 428         /* We hide that we have no struct page backing our stolen object
 429          * by wrapping the contiguous physical allocation with a fake
 430          * dma mapping in a single scatterlist.
 431          */
 432
 433         st = kmalloc(sizeof(*st), GFP_KERNEL);
 434         if (st == NULL)
 435                 return NULL;
 436
 437         if (sg_alloc_table(st, 1, GFP_KERNEL)) {
 438                 kfree(st);
 439                 return NULL;
 440         }
 441
 442         sg = st->sgl;
 443         sg->offset = 0;
 444         sg->length = size;
 445
 446         sg_dma_address(sg) = (dma_addr_t)dev_priv->mm.stolen_base + offset;
 447         sg_dma_len(sg) = size;
 448
 449         return st;
 450 }
 451
 452 static int i915_gem_object_get_pages_stolen(struct drm_i915_gem_object *obj)
 453 {
 454         BUG();
 455         return -EINVAL;
 456 }
 457
 458 static void i915_gem_object_put_pages_stolen(struct drm_i915_gem_object *obj)
 459 {
 460         /* Should only be called during free */
 461         sg_free_table(obj->pages);
 462         kfree(obj->pages);
 463 }
 464
 465
 466 static void
 467 i915_gem_object_release_stolen(struct drm_i915_gem_object *obj)
 468 {
 469         struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
 470
 471         if (obj->stolen) {
 472                 i915_gem_stolen_remove_node(dev_priv, obj->stolen);
 473                 kfree(obj->stolen);
 474                 obj->stolen = NULL;
 475         }
 476 }
 477 static const struct drm_i915_gem_object_ops i915_gem_object_stolen_ops = {
 478         .get_pages = i915_gem_object_get_pages_stolen,
 479         .put_pages = i915_gem_object_put_pages_stolen,
 480         .release = i915_gem_object_release_stolen,
 481 };
 482
 483 static struct drm_i915_gem_object *
 484 _i915_gem_object_create_stolen(struct drm_device *dev,
 485                                struct drm_mm_node *stolen)
 486 {
 487         struct drm_i915_gem_object *obj;
 488
 489         obj = i915_gem_object_alloc(dev);
 490         if (obj == NULL)
 491                 return NULL;
 492
 493         drm_gem_private_object_init(dev, &obj->base, stolen->size);
 494         i915_gem_object_init(obj, &i915_gem_object_stolen_ops);
 495
 496         obj->pages = i915_pages_create_for_stolen(dev,
 497                                                   stolen->start, stolen->size);
 498         if (obj->pages == NULL)
 499                 goto cleanup;
 500
 501         i915_gem_object_pin_pages(obj);
 502         obj->stolen = stolen;
 503
 504         obj->base.read_domains = I915_GEM_DOMAIN_CPU | I915_GEM_DOMAIN_GTT;
 505         obj->cache_level = HAS_LLC(dev) ? I915_CACHE_LLC : I915_CACHE_NONE;
 506
 507         return obj;
 508
 509 cleanup:
 510         i915_gem_object_free(obj);
 511         return NULL;
 512 }
 513
 514 struct drm_i915_gem_object *
 515 i915_gem_object_create_stolen(struct drm_device *dev, u32 size)
 516 {
 517         struct drm_i915_private *dev_priv = dev->dev_private;
 518         struct drm_i915_gem_object *obj;
 519         struct drm_mm_node *stolen;
 520         int ret;
 521
 522         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 523                 return NULL;
 524
 525         DRM_DEBUG_KMS("creating stolen object: size=%x\n", size);
 526         if (size == 0)
 527                 return NULL;
 528
 529         stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
 530         if (!stolen)
 531                 return NULL;
 532
 533         ret = i915_gem_stolen_insert_node(dev_priv, stolen, size, 4096);
 534         if (ret) {
 535                 kfree(stolen);
 536                 return NULL;
 537         }
 538
 539         obj = _i915_gem_object_create_stolen(dev, stolen);
 540         if (obj)
 541                 return obj;
 542
 543         i915_gem_stolen_remove_node(dev_priv, stolen);
 544         kfree(stolen);
 545         return NULL;
 546 }
 547
 548 struct drm_i915_gem_object *
 549 i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
 550                                                u32 stolen_offset,
 551                                                u32 gtt_offset,
 552                                                u32 size)
 553 {
 554         struct drm_i915_private *dev_priv = dev->dev_private;
 555         struct i915_address_space *ggtt = &dev_priv->gtt.base;
 556         struct drm_i915_gem_object *obj;
 557         struct drm_mm_node *stolen;
 558         struct i915_vma *vma;
 559         int ret;
 560
 561         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 562                 return NULL;
 563
 564         DRM_DEBUG_KMS("creating preallocated stolen object: stolen_offset=%x, gtt_offset=%x, size=%x\n",
 565                         stolen_offset, gtt_offset, size);
 566
 567         /* KISS and expect everything to be page-aligned */
 568         if (WARN_ON(size == 0) || WARN_ON(size & 4095) ||
 569             WARN_ON(stolen_offset & 4095))
 570                 return NULL;
 571
 572         stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
 573         if (!stolen)
 574                 return NULL;
 575
 576         stolen->start = stolen_offset;
 577         stolen->size = size;
 578         mutex_lock(&dev_priv->mm.stolen_lock);
 579         ret = drm_mm_reserve_node(&dev_priv->mm.stolen, stolen);
 580         mutex_unlock(&dev_priv->mm.stolen_lock);
 581         if (ret) {
 582                 DRM_DEBUG_KMS("failed to allocate stolen space\n");
 583                 kfree(stolen);
 584                 return NULL;
 585         }
 586
 587         obj = _i915_gem_object_create_stolen(dev, stolen);
 588         if (obj == NULL) {
 589                 DRM_DEBUG_KMS("failed to allocate stolen object\n");
 590                 i915_gem_stolen_remove_node(dev_priv, stolen);
 591                 kfree(stolen);
 592                 return NULL;
 593         }
 594
 595         /* Some objects just need physical mem from stolen space */
 596         if (gtt_offset == I915_GTT_OFFSET_NONE)
 597                 return obj;
 598
 599         vma = i915_gem_obj_lookup_or_create_vma(obj, ggtt);
 600         if (IS_ERR(vma)) {
 601                 ret = PTR_ERR(vma);
 602                 goto err;
 603         }
 604
 605         /* To simplify the initialisation sequence between KMS and GTT,
 606          * we allow construction of the stolen object prior to
 607          * setting up the GTT space. The actual reservation will occur
 608          * later.
 609          */
 610         vma->node.start = gtt_offset;
 611         vma->node.size = size;
 612         if (drm_mm_initialized(&ggtt->mm)) {
 613                 ret = drm_mm_reserve_node(&ggtt->mm, &vma->node);
 614                 if (ret) {
 615                         DRM_DEBUG_KMS("failed to allocate stolen GTT space\n");
 616                         goto err;
 617                 }
 618
 619                 vma->bound |= GLOBAL_BIND;
 620                 list_add_tail(&vma->mm_list, &ggtt->inactive_list);
 621         }
 622
 623         list_add_tail(&obj->global_list, &dev_priv->mm.bound_list);
 624         i915_gem_object_pin_pages(obj);
 625
 626         return obj;
 627
 628 err:
 629         drm_gem_object_unreference(&obj->base);
 630         return NULL;
 631 }