drivers/gpu/drm/i915/gem/i915_gem_stolen.c

   1 /*
   2  * SPDX-License-Identifier: MIT
   3  *
   4  * Copyright © 2008-2012 Intel Corporation
   5  */
   6
   7 #include <linux/errno.h>
   8 #include <linux/mutex.h>
   9
  10 #include <drm/drm_mm.h>
  11 #include <drm/i915_drm.h>
  12
  13 #include "gem/i915_gem_region.h"
  14 #include "i915_drv.h"
  15 #include "i915_gem_stolen.h"
  16 #include "i915_vgpu.h"
  17
  18 /*
  19  * The BIOS typically reserves some of the system's memory for the exclusive
  20  * use of the integrated graphics. This memory is no longer available for
  21  * use by the OS and so the user finds that his system has less memory
  22  * available than he put in. We refer to this memory as stolen.
  23  *
  24  * The BIOS will allocate its framebuffer from the stolen memory. Our
  25  * goal is try to reuse that object for our own fbcon which must always
  26  * be available for panics. Anything else we can reuse the stolen memory
  27  * for is a boon.
  28  */
  29
  30 int i915_gem_stolen_insert_node_in_range(struct drm_i915_private *i915,
  31                                          struct drm_mm_node *node, u64 size,
  32                                          unsigned alignment, u64 start, u64 end)
  33 {
  34         int ret;
  35
  36         if (!drm_mm_initialized(&i915->mm.stolen))
  37                 return -ENODEV;
  38
  39         /* WaSkipStolenMemoryFirstPage:bdw+ */
  40         if (INTEL_GEN(i915) >= 8 && start < 4096)
  41                 start = 4096;
  42
  43         mutex_lock(&i915->mm.stolen_lock);
  44         ret = drm_mm_insert_node_in_range(&i915->mm.stolen, node,
  45                                           size, alignment, 0,
  46                                           start, end, DRM_MM_INSERT_BEST);
  47         mutex_unlock(&i915->mm.stolen_lock);
  48
  49         return ret;
  50 }
  51
  52 int i915_gem_stolen_insert_node(struct drm_i915_private *i915,
  53                                 struct drm_mm_node *node, u64 size,
  54                                 unsigned alignment)
  55 {
  56         return i915_gem_stolen_insert_node_in_range(i915, node, size,
  57                                                     alignment, 0, U64_MAX);
  58 }
  59
  60 void i915_gem_stolen_remove_node(struct drm_i915_private *i915,
  61                                  struct drm_mm_node *node)
  62 {
  63         mutex_lock(&i915->mm.stolen_lock);
  64         drm_mm_remove_node(node);
  65         mutex_unlock(&i915->mm.stolen_lock);
  66 }
  67
  68 static int i915_adjust_stolen(struct drm_i915_private *i915,
  69                               struct resource *dsm)
  70 {
  71         struct i915_ggtt *ggtt = &i915->ggtt;
  72         struct intel_uncore *uncore = ggtt->vm.gt->uncore;
  73         struct resource *r;
  74
  75         if (dsm->start == 0 || dsm->end <= dsm->start)
  76                 return -EINVAL;
  77
  78         /*
  79          * TODO: We have yet too encounter the case where the GTT wasn't at the
  80          * end of stolen. With that assumption we could simplify this.
  81          */
  82
  83         /* Make sure we don't clobber the GTT if it's within stolen memory */
  84         if (INTEL_GEN(i915) <= 4 &&
  85             !IS_G33(i915) && !IS_PINEVIEW(i915) && !IS_G4X(i915)) {
  86                 struct resource stolen[2] = {*dsm, *dsm};
  87                 struct resource ggtt_res;
  88                 resource_size_t ggtt_start;
  89
  90                 ggtt_start = intel_uncore_read(uncore, PGTBL_CTL);
  91                 if (IS_GEN(i915, 4))
  92                         ggtt_start = (ggtt_start & PGTBL_ADDRESS_LO_MASK) |
  93                                      (ggtt_start & PGTBL_ADDRESS_HI_MASK) << 28;
  94                 else
  95                         ggtt_start &= PGTBL_ADDRESS_LO_MASK;
  96
  97                 ggtt_res =
  98                         (struct resource) DEFINE_RES_MEM(ggtt_start,
  99                                                          ggtt_total_entries(ggtt) * 4);
 100
 101                 if (ggtt_res.start >= stolen[0].start && ggtt_res.start < stolen[0].end)
 102                         stolen[0].end = ggtt_res.start;
 103                 if (ggtt_res.end > stolen[1].start && ggtt_res.end <= stolen[1].end)
 104                         stolen[1].start = ggtt_res.end;
 105
 106                 /* Pick the larger of the two chunks */
 107                 if (resource_size(&stolen[0]) > resource_size(&stolen[1]))
 108                         *dsm = stolen[0];
 109                 else
 110                         *dsm = stolen[1];
 111
 112                 if (stolen[0].start != stolen[1].start ||
 113                     stolen[0].end != stolen[1].end) {
 114                         drm_dbg(&i915->drm,
 115                                 "GTT within stolen memory at %pR\n",
 116                                 &ggtt_res);
 117                         drm_dbg(&i915->drm, "Stolen memory adjusted to %pR\n",
 118                                 dsm);
 119                 }
 120         }
 121
 122         /*
 123          * Verify that nothing else uses this physical address. Stolen
 124          * memory should be reserved by the BIOS and hidden from the
 125          * kernel. So if the region is already marked as busy, something
 126          * is seriously wrong.
 127          */
 128         r = devm_request_mem_region(i915->drm.dev, dsm->start,
 129                                     resource_size(dsm),
 130                                     "Graphics Stolen Memory");
 131         if (r == NULL) {
 132                 /*
 133                  * One more attempt but this time requesting region from
 134                  * start + 1, as we have seen that this resolves the region
 135                  * conflict with the PCI Bus.
 136                  * This is a BIOS w/a: Some BIOS wrap stolen in the root
 137                  * PCI bus, but have an off-by-one error. Hence retry the
 138                  * reservation starting from 1 instead of 0.
 139                  * There's also BIOS with off-by-one on the other end.
 140                  */
 141                 r = devm_request_mem_region(i915->drm.dev, dsm->start + 1,
 142                                             resource_size(dsm) - 2,
 143                                             "Graphics Stolen Memory");
 144                 /*
 145                  * GEN3 firmware likes to smash pci bridges into the stolen
 146                  * range. Apparently this works.
 147                  */
 148                 if (!r && !IS_GEN(i915, 3)) {
 149                         drm_err(&i915->drm,
 150                                 "conflict detected with stolen region: %pR\n",
 151                                 dsm);
 152
 153                         return -EBUSY;
 154                 }
 155         }
 156
 157         return 0;
 158 }
 159
 160 static void i915_gem_cleanup_stolen(struct drm_i915_private *i915)
 161 {
 162         if (!drm_mm_initialized(&i915->mm.stolen))
 163                 return;
 164
 165         drm_mm_takedown(&i915->mm.stolen);
 166 }
 167
 168 static void g4x_get_stolen_reserved(struct drm_i915_private *i915,
 169                                     struct intel_uncore *uncore,
 170                                     resource_size_t *base,
 171                                     resource_size_t *size)
 172 {
 173         u32 reg_val = intel_uncore_read(uncore,
 174                                         IS_GM45(i915) ?
 175                                         CTG_STOLEN_RESERVED :
 176                                         ELK_STOLEN_RESERVED);
 177         resource_size_t stolen_top = i915->dsm.end + 1;
 178
 179         drm_dbg(&i915->drm, "%s_STOLEN_RESERVED = %08x\n",
 180                 IS_GM45(i915) ? "CTG" : "ELK", reg_val);
 181
 182         if ((reg_val & G4X_STOLEN_RESERVED_ENABLE) == 0)
 183                 return;
 184
 185         /*
 186          * Whether ILK really reuses the ELK register for this is unclear.
 187          * Let's see if we catch anyone with this supposedly enabled on ILK.
 188          */
 189         drm_WARN(&i915->drm, IS_GEN(i915, 5),
 190                  "ILK stolen reserved found? 0x%08x\n",
 191                  reg_val);
 192
 193         if (!(reg_val & G4X_STOLEN_RESERVED_ADDR2_MASK))
 194                 return;
 195
 196         *base = (reg_val & G4X_STOLEN_RESERVED_ADDR2_MASK) << 16;
 197         drm_WARN_ON(&i915->drm,
 198                     (reg_val & G4X_STOLEN_RESERVED_ADDR1_MASK) < *base);
 199
 200         *size = stolen_top - *base;
 201 }
 202
 203 static void gen6_get_stolen_reserved(struct drm_i915_private *i915,
 204                                      struct intel_uncore *uncore,
 205                                      resource_size_t *base,
 206                                      resource_size_t *size)
 207 {
 208         u32 reg_val = intel_uncore_read(uncore, GEN6_STOLEN_RESERVED);
 209
 210         drm_dbg(&i915->drm, "GEN6_STOLEN_RESERVED = %08x\n", reg_val);
 211
 212         if (!(reg_val & GEN6_STOLEN_RESERVED_ENABLE))
 213                 return;
 214
 215         *base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
 216
 217         switch (reg_val & GEN6_STOLEN_RESERVED_SIZE_MASK) {
 218         case GEN6_STOLEN_RESERVED_1M:
 219                 *size = 1024 * 1024;
 220                 break;
 221         case GEN6_STOLEN_RESERVED_512K:
 222                 *size = 512 * 1024;
 223                 break;
 224         case GEN6_STOLEN_RESERVED_256K:
 225                 *size = 256 * 1024;
 226                 break;
 227         case GEN6_STOLEN_RESERVED_128K:
 228                 *size = 128 * 1024;
 229                 break;
 230         default:
 231                 *size = 1024 * 1024;
 232                 MISSING_CASE(reg_val & GEN6_STOLEN_RESERVED_SIZE_MASK);
 233         }
 234 }
 235
 236 static void vlv_get_stolen_reserved(struct drm_i915_private *i915,
 237                                     struct intel_uncore *uncore,
 238                                     resource_size_t *base,
 239                                     resource_size_t *size)
 240 {
 241         u32 reg_val = intel_uncore_read(uncore, GEN6_STOLEN_RESERVED);
 242         resource_size_t stolen_top = i915->dsm.end + 1;
 243
 244         drm_dbg(&i915->drm, "GEN6_STOLEN_RESERVED = %08x\n", reg_val);
 245
 246         if (!(reg_val & GEN6_STOLEN_RESERVED_ENABLE))
 247                 return;
 248
 249         switch (reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK) {
 250         default:
 251                 MISSING_CASE(reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK);
 252                 fallthrough;
 253         case GEN7_STOLEN_RESERVED_1M:
 254                 *size = 1024 * 1024;
 255                 break;
 256         }
 257
 258         /*
 259          * On vlv, the ADDR_MASK portion is left as 0 and HW deduces the
 260          * reserved location as (top - size).
 261          */
 262         *base = stolen_top - *size;
 263 }
 264
 265 static void gen7_get_stolen_reserved(struct drm_i915_private *i915,
 266                                      struct intel_uncore *uncore,
 267                                      resource_size_t *base,
 268                                      resource_size_t *size)
 269 {
 270         u32 reg_val = intel_uncore_read(uncore, GEN6_STOLEN_RESERVED);
 271
 272         drm_dbg(&i915->drm, "GEN6_STOLEN_RESERVED = %08x\n", reg_val);
 273
 274         if (!(reg_val & GEN6_STOLEN_RESERVED_ENABLE))
 275                 return;
 276
 277         *base = reg_val & GEN7_STOLEN_RESERVED_ADDR_MASK;
 278
 279         switch (reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK) {
 280         case GEN7_STOLEN_RESERVED_1M:
 281                 *size = 1024 * 1024;
 282                 break;
 283         case GEN7_STOLEN_RESERVED_256K:
 284                 *size = 256 * 1024;
 285                 break;
 286         default:
 287                 *size = 1024 * 1024;
 288                 MISSING_CASE(reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK);
 289         }
 290 }
 291
 292 static void chv_get_stolen_reserved(struct drm_i915_private *i915,
 293                                     struct intel_uncore *uncore,
 294                                     resource_size_t *base,
 295                                     resource_size_t *size)
 296 {
 297         u32 reg_val = intel_uncore_read(uncore, GEN6_STOLEN_RESERVED);
 298
 299         drm_dbg(&i915->drm, "GEN6_STOLEN_RESERVED = %08x\n", reg_val);
 300
 301         if (!(reg_val & GEN6_STOLEN_RESERVED_ENABLE))
 302                 return;
 303
 304         *base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
 305
 306         switch (reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK) {
 307         case GEN8_STOLEN_RESERVED_1M:
 308                 *size = 1024 * 1024;
 309                 break;
 310         case GEN8_STOLEN_RESERVED_2M:
 311                 *size = 2 * 1024 * 1024;
 312                 break;
 313         case GEN8_STOLEN_RESERVED_4M:
 314                 *size = 4 * 1024 * 1024;
 315                 break;
 316         case GEN8_STOLEN_RESERVED_8M:
 317                 *size = 8 * 1024 * 1024;
 318                 break;
 319         default:
 320                 *size = 8 * 1024 * 1024;
 321                 MISSING_CASE(reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK);
 322         }
 323 }
 324
 325 static void bdw_get_stolen_reserved(struct drm_i915_private *i915,
 326                                     struct intel_uncore *uncore,
 327                                     resource_size_t *base,
 328                                     resource_size_t *size)
 329 {
 330         u32 reg_val = intel_uncore_read(uncore, GEN6_STOLEN_RESERVED);
 331         resource_size_t stolen_top = i915->dsm.end + 1;
 332
 333         drm_dbg(&i915->drm, "GEN6_STOLEN_RESERVED = %08x\n", reg_val);
 334
 335         if (!(reg_val & GEN6_STOLEN_RESERVED_ENABLE))
 336                 return;
 337
 338         if (!(reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK))
 339                 return;
 340
 341         *base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
 342         *size = stolen_top - *base;
 343 }
 344
 345 static void icl_get_stolen_reserved(struct drm_i915_private *i915,
 346                                     struct intel_uncore *uncore,
 347                                     resource_size_t *base,
 348                                     resource_size_t *size)
 349 {
 350         u64 reg_val = intel_uncore_read64(uncore, GEN6_STOLEN_RESERVED);
 351
 352         drm_dbg(&i915->drm, "GEN6_STOLEN_RESERVED = 0x%016llx\n", reg_val);
 353
 354         *base = reg_val & GEN11_STOLEN_RESERVED_ADDR_MASK;
 355
 356         switch (reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK) {
 357         case GEN8_STOLEN_RESERVED_1M:
 358                 *size = 1024 * 1024;
 359                 break;
 360         case GEN8_STOLEN_RESERVED_2M:
 361                 *size = 2 * 1024 * 1024;
 362                 break;
 363         case GEN8_STOLEN_RESERVED_4M:
 364                 *size = 4 * 1024 * 1024;
 365                 break;
 366         case GEN8_STOLEN_RESERVED_8M:
 367                 *size = 8 * 1024 * 1024;
 368                 break;
 369         default:
 370                 *size = 8 * 1024 * 1024;
 371                 MISSING_CASE(reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK);
 372         }
 373 }
 374
 375 static int i915_gem_init_stolen(struct drm_i915_private *i915)
 376 {
 377         struct intel_uncore *uncore = &i915->uncore;
 378         resource_size_t reserved_base, stolen_top;
 379         resource_size_t reserved_total, reserved_size;
 380
 381         mutex_init(&i915->mm.stolen_lock);
 382
 383         if (intel_vgpu_active(i915)) {
 384                 drm_notice(&i915->drm,
 385                            "%s, disabling use of stolen memory\n",
 386                            "iGVT-g active");
 387                 return 0;
 388         }
 389
 390         if (intel_vtd_active() && INTEL_GEN(i915) < 8) {
 391                 drm_notice(&i915->drm,
 392                            "%s, disabling use of stolen memory\n",
 393                            "DMAR active");
 394                 return 0;
 395         }
 396
 397         if (resource_size(&intel_graphics_stolen_res) == 0)
 398                 return 0;
 399
 400         i915->dsm = intel_graphics_stolen_res;
 401
 402         if (i915_adjust_stolen(i915, &i915->dsm))
 403                 return 0;
 404
 405         GEM_BUG_ON(i915->dsm.start == 0);
 406         GEM_BUG_ON(i915->dsm.end <= i915->dsm.start);
 407
 408         stolen_top = i915->dsm.end + 1;
 409         reserved_base = stolen_top;
 410         reserved_size = 0;
 411
 412         switch (INTEL_GEN(i915)) {
 413         case 2:
 414         case 3:
 415                 break;
 416         case 4:
 417                 if (!IS_G4X(i915))
 418                         break;
 419                 fallthrough;
 420         case 5:
 421                 g4x_get_stolen_reserved(i915, uncore,
 422                                         &reserved_base, &reserved_size);
 423                 break;
 424         case 6:
 425                 gen6_get_stolen_reserved(i915, uncore,
 426                                          &reserved_base, &reserved_size);
 427                 break;
 428         case 7:
 429                 if (IS_VALLEYVIEW(i915))
 430                         vlv_get_stolen_reserved(i915, uncore,
 431                                                 &reserved_base, &reserved_size);
 432                 else
 433                         gen7_get_stolen_reserved(i915, uncore,
 434                                                  &reserved_base, &reserved_size);
 435                 break;
 436         case 8:
 437         case 9:
 438         case 10:
 439                 if (IS_LP(i915))
 440                         chv_get_stolen_reserved(i915, uncore,
 441                                                 &reserved_base, &reserved_size);
 442                 else
 443                         bdw_get_stolen_reserved(i915, uncore,
 444                                                 &reserved_base, &reserved_size);
 445                 break;
 446         default:
 447                 MISSING_CASE(INTEL_GEN(i915));
 448                 fallthrough;
 449         case 11:
 450         case 12:
 451                 icl_get_stolen_reserved(i915, uncore,
 452                                         &reserved_base,
 453                                         &reserved_size);
 454                 break;
 455         }
 456
 457         /*
 458          * Our expectation is that the reserved space is at the top of the
 459          * stolen region and *never* at the bottom. If we see !reserved_base,
 460          * it likely means we failed to read the registers correctly.
 461          */
 462         if (!reserved_base) {
 463                 drm_err(&i915->drm,
 464                         "inconsistent reservation %pa + %pa; ignoring\n",
 465                         &reserved_base, &reserved_size);
 466                 reserved_base = stolen_top;
 467                 reserved_size = 0;
 468         }
 469
 470         i915->dsm_reserved =
 471                 (struct resource)DEFINE_RES_MEM(reserved_base, reserved_size);
 472
 473         if (!resource_contains(&i915->dsm, &i915->dsm_reserved)) {
 474                 drm_err(&i915->drm,
 475                         "Stolen reserved area %pR outside stolen memory %pR\n",
 476                         &i915->dsm_reserved, &i915->dsm);
 477                 return 0;
 478         }
 479
 480         /* It is possible for the reserved area to end before the end of stolen
 481          * memory, so just consider the start. */
 482         reserved_total = stolen_top - reserved_base;
 483
 484         drm_dbg(&i915->drm,
 485                 "Memory reserved for graphics device: %lluK, usable: %lluK\n",
 486                 (u64)resource_size(&i915->dsm) >> 10,
 487                 ((u64)resource_size(&i915->dsm) - reserved_total) >> 10);
 488
 489         i915->stolen_usable_size =
 490                 resource_size(&i915->dsm) - reserved_total;
 491
 492         /* Basic memrange allocator for stolen space. */
 493         drm_mm_init(&i915->mm.stolen, 0, i915->stolen_usable_size);
 494
 495         return 0;
 496 }
 497
 498 static struct sg_table *
 499 i915_pages_create_for_stolen(struct drm_device *dev,
 500                              resource_size_t offset, resource_size_t size)
 501 {
 502         struct drm_i915_private *i915 = to_i915(dev);
 503         struct sg_table *st;
 504         struct scatterlist *sg;
 505
 506         GEM_BUG_ON(range_overflows(offset, size, resource_size(&i915->dsm)));
 507
 508         /* We hide that we have no struct page backing our stolen object
 509          * by wrapping the contiguous physical allocation with a fake
 510          * dma mapping in a single scatterlist.
 511          */
 512
 513         st = kmalloc(sizeof(*st), GFP_KERNEL);
 514         if (st == NULL)
 515                 return ERR_PTR(-ENOMEM);
 516
 517         if (sg_alloc_table(st, 1, GFP_KERNEL)) {
 518                 kfree(st);
 519                 return ERR_PTR(-ENOMEM);
 520         }
 521
 522         sg = st->sgl;
 523         sg->offset = 0;
 524         sg->length = size;
 525
 526         sg_dma_address(sg) = (dma_addr_t)i915->dsm.start + offset;
 527         sg_dma_len(sg) = size;
 528
 529         return st;
 530 }
 531
 532 static int i915_gem_object_get_pages_stolen(struct drm_i915_gem_object *obj)
 533 {
 534         struct sg_table *pages =
 535                 i915_pages_create_for_stolen(obj->base.dev,
 536                                              obj->stolen->start,
 537                                              obj->stolen->size);
 538         if (IS_ERR(pages))
 539                 return PTR_ERR(pages);
 540
 541         __i915_gem_object_set_pages(obj, pages, obj->stolen->size);
 542
 543         return 0;
 544 }
 545
 546 static void i915_gem_object_put_pages_stolen(struct drm_i915_gem_object *obj,
 547                                              struct sg_table *pages)
 548 {
 549         /* Should only be called from i915_gem_object_release_stolen() */
 550         sg_free_table(pages);
 551         kfree(pages);
 552 }
 553
 554 static void
 555 i915_gem_object_release_stolen(struct drm_i915_gem_object *obj)
 556 {
 557         struct drm_i915_private *i915 = to_i915(obj->base.dev);
 558         struct drm_mm_node *stolen = fetch_and_zero(&obj->stolen);
 559
 560         GEM_BUG_ON(!stolen);
 561
 562         i915_gem_object_release_memory_region(obj);
 563
 564         i915_gem_stolen_remove_node(i915, stolen);
 565         kfree(stolen);
 566 }
 567
 568 static const struct drm_i915_gem_object_ops i915_gem_object_stolen_ops = {
 569         .name = "i915_gem_object_stolen",
 570         .get_pages = i915_gem_object_get_pages_stolen,
 571         .put_pages = i915_gem_object_put_pages_stolen,
 572         .release = i915_gem_object_release_stolen,
 573 };
 574
 575 static struct drm_i915_gem_object *
 576 __i915_gem_object_create_stolen(struct intel_memory_region *mem,
 577                                 struct drm_mm_node *stolen)
 578 {
 579         static struct lock_class_key lock_class;
 580         struct drm_i915_gem_object *obj;
 581         unsigned int cache_level;
 582         int err = -ENOMEM;
 583
 584         obj = i915_gem_object_alloc();
 585         if (!obj)
 586                 goto err;
 587
 588         drm_gem_private_object_init(&mem->i915->drm, &obj->base, stolen->size);
 589         i915_gem_object_init(obj, &i915_gem_object_stolen_ops, &lock_class);
 590
 591         obj->stolen = stolen;
 592         obj->read_domains = I915_GEM_DOMAIN_CPU | I915_GEM_DOMAIN_GTT;
 593         cache_level = HAS_LLC(mem->i915) ? I915_CACHE_LLC : I915_CACHE_NONE;
 594         i915_gem_object_set_cache_coherency(obj, cache_level);
 595
 596         err = i915_gem_object_pin_pages(obj);
 597         if (err)
 598                 goto cleanup;
 599
 600         i915_gem_object_init_memory_region(obj, mem, 0);
 601
 602         return obj;
 603
 604 cleanup:
 605         i915_gem_object_free(obj);
 606 err:
 607         return ERR_PTR(err);
 608 }
 609
 610 static struct drm_i915_gem_object *
 611 _i915_gem_object_create_stolen(struct intel_memory_region *mem,
 612                                resource_size_t size,
 613                                unsigned int flags)
 614 {
 615         struct drm_i915_private *i915 = mem->i915;
 616         struct drm_i915_gem_object *obj;
 617         struct drm_mm_node *stolen;
 618         int ret;
 619
 620         if (!drm_mm_initialized(&i915->mm.stolen))
 621                 return ERR_PTR(-ENODEV);
 622
 623         if (size == 0)
 624                 return ERR_PTR(-EINVAL);
 625
 626         stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
 627         if (!stolen)
 628                 return ERR_PTR(-ENOMEM);
 629
 630         ret = i915_gem_stolen_insert_node(i915, stolen, size, 4096);
 631         if (ret) {
 632                 obj = ERR_PTR(ret);
 633                 goto err_free;
 634         }
 635
 636         obj = __i915_gem_object_create_stolen(mem, stolen);
 637         if (IS_ERR(obj))
 638                 goto err_remove;
 639
 640         return obj;
 641
 642 err_remove:
 643         i915_gem_stolen_remove_node(i915, stolen);
 644 err_free:
 645         kfree(stolen);
 646         return obj;
 647 }
 648
 649 struct drm_i915_gem_object *
 650 i915_gem_object_create_stolen(struct drm_i915_private *i915,
 651                               resource_size_t size)
 652 {
 653         return i915_gem_object_create_region(i915->mm.regions[INTEL_REGION_STOLEN],
 654                                              size, I915_BO_ALLOC_CONTIGUOUS);
 655 }
 656
 657 static int init_stolen(struct intel_memory_region *mem)
 658 {
 659         intel_memory_region_set_name(mem, "stolen");
 660
 661         /*
 662          * Initialise stolen early so that we may reserve preallocated
 663          * objects for the BIOS to KMS transition.
 664          */
 665         return i915_gem_init_stolen(mem->i915);
 666 }
 667
 668 static void release_stolen(struct intel_memory_region *mem)
 669 {
 670         i915_gem_cleanup_stolen(mem->i915);
 671 }
 672
 673 static const struct intel_memory_region_ops i915_region_stolen_ops = {
 674         .init = init_stolen,
 675         .release = release_stolen,
 676         .create_object = _i915_gem_object_create_stolen,
 677 };
 678
 679 struct intel_memory_region *i915_gem_stolen_setup(struct drm_i915_private *i915)
 680 {
 681         return intel_memory_region_create(i915,
 682                                           intel_graphics_stolen_res.start,
 683                                           resource_size(&intel_graphics_stolen_res),
 684                                           PAGE_SIZE, 0,
 685                                           &i915_region_stolen_ops);
 686 }
 687
 688 struct drm_i915_gem_object *
 689 i915_gem_object_create_stolen_for_preallocated(struct drm_i915_private *i915,
 690                                                resource_size_t stolen_offset,
 691                                                resource_size_t size)
 692 {
 693         struct intel_memory_region *mem = i915->mm.regions[INTEL_REGION_STOLEN];
 694         struct drm_i915_gem_object *obj;
 695         struct drm_mm_node *stolen;
 696         int ret;
 697
 698         if (!drm_mm_initialized(&i915->mm.stolen))
 699                 return ERR_PTR(-ENODEV);
 700
 701         drm_dbg(&i915->drm,
 702                 "creating preallocated stolen object: stolen_offset=%pa, size=%pa\n",
 703                 &stolen_offset, &size);
 704
 705         /* KISS and expect everything to be page-aligned */
 706         if (GEM_WARN_ON(size == 0) ||
 707             GEM_WARN_ON(!IS_ALIGNED(size, I915_GTT_PAGE_SIZE)) ||
 708             GEM_WARN_ON(!IS_ALIGNED(stolen_offset, I915_GTT_MIN_ALIGNMENT)))
 709                 return ERR_PTR(-EINVAL);
 710
 711         stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
 712         if (!stolen)
 713                 return ERR_PTR(-ENOMEM);
 714
 715         stolen->start = stolen_offset;
 716         stolen->size = size;
 717         mutex_lock(&i915->mm.stolen_lock);
 718         ret = drm_mm_reserve_node(&i915->mm.stolen, stolen);
 719         mutex_unlock(&i915->mm.stolen_lock);
 720         if (ret) {
 721                 obj = ERR_PTR(ret);
 722                 goto err_free;
 723         }
 724
 725         obj = __i915_gem_object_create_stolen(mem, stolen);
 726         if (IS_ERR(obj))
 727                 goto err_stolen;
 728
 729         i915_gem_object_set_cache_coherency(obj, I915_CACHE_NONE);
 730         return obj;
 731
 732 err_stolen:
 733         i915_gem_stolen_remove_node(i915, stolen);
 734 err_free:
 735         kfree(stolen);
 736         return obj;
 737 }