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 #define KB(x) ((x) * 1024)
  34 #define MB(x) (KB(x) * 1024)
  35
  36 /*
  37  * The BIOS typically reserves some of the system's memory for the exclusive
  38  * use of the integrated graphics. This memory is no longer available for
  39  * use by the OS and so the user finds that his system has less memory
  40  * available than he put in. We refer to this memory as stolen.
  41  *
  42  * The BIOS will allocate its framebuffer from the stolen memory. Our
  43  * goal is try to reuse that object for our own fbcon which must always
  44  * be available for panics. Anything else we can reuse the stolen memory
  45  * for is a boon.
  46  */
  47
  48 int i915_gem_stolen_insert_node_in_range(struct drm_i915_private *dev_priv,
  49                                          struct drm_mm_node *node, u64 size,
  50                                          unsigned alignment, u64 start, u64 end)
  51 {
  52         int ret;
  53
  54         if (!drm_mm_initialized(&dev_priv->mm.stolen))
  55                 return -ENODEV;
  56
  57         /* See the comment at the drm_mm_init() call for more about this check.
  58          * WaSkipStolenMemoryFirstPage:bdw,chv,kbl (incomplete)
  59          */
  60         if (start < 4096 && (IS_GEN8(dev_priv) ||
  61                              IS_KBL_REVID(dev_priv, 0, KBL_REVID_A0)))
  62                 start = 4096;
  63
  64         mutex_lock(&dev_priv->mm.stolen_lock);
  65         ret = drm_mm_insert_node_in_range(&dev_priv->mm.stolen, node, size,
  66                                           alignment, start, end,
  67                                           DRM_MM_SEARCH_DEFAULT);
  68         mutex_unlock(&dev_priv->mm.stolen_lock);
  69
  70         return ret;
  71 }
  72
  73 int i915_gem_stolen_insert_node(struct drm_i915_private *dev_priv,
  74                                 struct drm_mm_node *node, u64 size,
  75                                 unsigned alignment)
  76 {
  77         struct i915_ggtt *ggtt = &dev_priv->ggtt;
  78
  79         return i915_gem_stolen_insert_node_in_range(dev_priv, node, size,
  80                                                     alignment, 0,
  81                                                     ggtt->stolen_usable_size);
  82 }
  83
  84 void i915_gem_stolen_remove_node(struct drm_i915_private *dev_priv,
  85                                  struct drm_mm_node *node)
  86 {
  87         mutex_lock(&dev_priv->mm.stolen_lock);
  88         drm_mm_remove_node(node);
  89         mutex_unlock(&dev_priv->mm.stolen_lock);
  90 }
  91
  92 static unsigned long i915_stolen_to_physical(struct drm_i915_private *dev_priv)
  93 {
  94         struct pci_dev *pdev = dev_priv->drm.pdev;
  95         struct i915_ggtt *ggtt = &dev_priv->ggtt;
  96         struct resource *r;
  97         u32 base;
  98
  99         /* Almost universally we can find the Graphics Base of Stolen Memory
 100          * at register BSM (0x5c) in the igfx configuration space. On a few
 101          * (desktop) machines this is also mirrored in the bridge device at
 102          * different locations, or in the MCHBAR.
 103          *
 104          * On 865 we just check the TOUD register.
 105          *
 106          * On 830/845/85x the stolen memory base isn't available in any
 107          * register. We need to calculate it as TOM-TSEG_SIZE-stolen_size.
 108          *
 109          */
 110         base = 0;
 111         if (INTEL_GEN(dev_priv) >= 3) {
 112                 u32 bsm;
 113
 114                 pci_read_config_dword(pdev, INTEL_BSM, &bsm);
 115
 116                 base = bsm & INTEL_BSM_MASK;
 117         } else if (IS_I865G(dev_priv)) {
 118                 u32 tseg_size = 0;
 119                 u16 toud = 0;
 120                 u8 tmp;
 121
 122                 pci_bus_read_config_byte(pdev->bus, PCI_DEVFN(0, 0),
 123                                          I845_ESMRAMC, &tmp);
 124
 125                 if (tmp & TSEG_ENABLE) {
 126                         switch (tmp & I845_TSEG_SIZE_MASK) {
 127                         case I845_TSEG_SIZE_512K:
 128                                 tseg_size = KB(512);
 129                                 break;
 130                         case I845_TSEG_SIZE_1M:
 131                                 tseg_size = MB(1);
 132                                 break;
 133                         }
 134                 }
 135
 136                 pci_bus_read_config_word(pdev->bus, PCI_DEVFN(0, 0),
 137                                          I865_TOUD, &toud);
 138
 139                 base = (toud << 16) + tseg_size;
 140         } else if (IS_I85X(dev_priv)) {
 141                 u32 tseg_size = 0;
 142                 u32 tom;
 143                 u8 tmp;
 144
 145                 pci_bus_read_config_byte(pdev->bus, PCI_DEVFN(0, 0),
 146                                          I85X_ESMRAMC, &tmp);
 147
 148                 if (tmp & TSEG_ENABLE)
 149                         tseg_size = MB(1);
 150
 151                 pci_bus_read_config_byte(pdev->bus, PCI_DEVFN(0, 1),
 152                                          I85X_DRB3, &tmp);
 153                 tom = tmp * MB(32);
 154
 155                 base = tom - tseg_size - ggtt->stolen_size;
 156         } else if (IS_I845G(dev_priv)) {
 157                 u32 tseg_size = 0;
 158                 u32 tom;
 159                 u8 tmp;
 160
 161                 pci_bus_read_config_byte(pdev->bus, PCI_DEVFN(0, 0),
 162                                          I845_ESMRAMC, &tmp);
 163
 164                 if (tmp & TSEG_ENABLE) {
 165                         switch (tmp & I845_TSEG_SIZE_MASK) {
 166                         case I845_TSEG_SIZE_512K:
 167                                 tseg_size = KB(512);
 168                                 break;
 169                         case I845_TSEG_SIZE_1M:
 170                                 tseg_size = MB(1);
 171                                 break;
 172                         }
 173                 }
 174
 175                 pci_bus_read_config_byte(pdev->bus, PCI_DEVFN(0, 0),
 176                                          I830_DRB3, &tmp);
 177                 tom = tmp * MB(32);
 178
 179                 base = tom - tseg_size - ggtt->stolen_size;
 180         } else if (IS_I830(dev_priv)) {
 181                 u32 tseg_size = 0;
 182                 u32 tom;
 183                 u8 tmp;
 184
 185                 pci_bus_read_config_byte(pdev->bus, PCI_DEVFN(0, 0),
 186                                          I830_ESMRAMC, &tmp);
 187
 188                 if (tmp & TSEG_ENABLE) {
 189                         if (tmp & I830_TSEG_SIZE_1M)
 190                                 tseg_size = MB(1);
 191                         else
 192                                 tseg_size = KB(512);
 193                 }
 194
 195                 pci_bus_read_config_byte(pdev->bus, PCI_DEVFN(0, 0),
 196                                          I830_DRB3, &tmp);
 197                 tom = tmp * MB(32);
 198
 199                 base = tom - tseg_size - ggtt->stolen_size;
 200         }
 201
 202         if (base == 0)
 203                 return 0;
 204
 205         /* make sure we don't clobber the GTT if it's within stolen memory */
 206         if (INTEL_GEN(dev_priv) <= 4 && !IS_G33(dev_priv) &&
 207             !IS_G4X(dev_priv)) {
 208                 struct {
 209                         u32 start, end;
 210                 } stolen[2] = {
 211                         { .start = base, .end = base + ggtt->stolen_size, },
 212                         { .start = base, .end = base + ggtt->stolen_size, },
 213                 };
 214                 u64 ggtt_start, ggtt_end;
 215
 216                 ggtt_start = I915_READ(PGTBL_CTL);
 217                 if (IS_GEN4(dev_priv))
 218                         ggtt_start = (ggtt_start & PGTBL_ADDRESS_LO_MASK) |
 219                                      (ggtt_start & PGTBL_ADDRESS_HI_MASK) << 28;
 220                 else
 221                         ggtt_start &= PGTBL_ADDRESS_LO_MASK;
 222                 ggtt_end = ggtt_start + ggtt_total_entries(ggtt) * 4;
 223
 224                 if (ggtt_start >= stolen[0].start && ggtt_start < stolen[0].end)
 225                         stolen[0].end = ggtt_start;
 226                 if (ggtt_end > stolen[1].start && ggtt_end <= stolen[1].end)
 227                         stolen[1].start = ggtt_end;
 228
 229                 /* pick the larger of the two chunks */
 230                 if (stolen[0].end - stolen[0].start >
 231                     stolen[1].end - stolen[1].start) {
 232                         base = stolen[0].start;
 233                         ggtt->stolen_size = stolen[0].end - stolen[0].start;
 234                 } else {
 235                         base = stolen[1].start;
 236                         ggtt->stolen_size = stolen[1].end - stolen[1].start;
 237                 }
 238
 239                 if (stolen[0].start != stolen[1].start ||
 240                     stolen[0].end != stolen[1].end) {
 241                         DRM_DEBUG_KMS("GTT within stolen memory at 0x%llx-0x%llx\n",
 242                                       (unsigned long long)ggtt_start,
 243                                       (unsigned long long)ggtt_end - 1);
 244                         DRM_DEBUG_KMS("Stolen memory adjusted to 0x%x-0x%x\n",
 245                                       base, base + (u32)ggtt->stolen_size - 1);
 246                 }
 247         }
 248
 249
 250         /* Verify that nothing else uses this physical address. Stolen
 251          * memory should be reserved by the BIOS and hidden from the
 252          * kernel. So if the region is already marked as busy, something
 253          * is seriously wrong.
 254          */
 255         r = devm_request_mem_region(dev_priv->drm.dev, base, ggtt->stolen_size,
 256                                     "Graphics Stolen Memory");
 257         if (r == NULL) {
 258                 /*
 259                  * One more attempt but this time requesting region from
 260                  * base + 1, as we have seen that this resolves the region
 261                  * conflict with the PCI Bus.
 262                  * This is a BIOS w/a: Some BIOS wrap stolen in the root
 263                  * PCI bus, but have an off-by-one error. Hence retry the
 264                  * reservation starting from 1 instead of 0.
 265                  */
 266                 r = devm_request_mem_region(dev_priv->drm.dev, base + 1,
 267                                             ggtt->stolen_size - 1,
 268                                             "Graphics Stolen Memory");
 269                 /*
 270                  * GEN3 firmware likes to smash pci bridges into the stolen
 271                  * range. Apparently this works.
 272                  */
 273                 if (r == NULL && !IS_GEN3(dev_priv)) {
 274                         DRM_ERROR("conflict detected with stolen region: [0x%08x - 0x%08x]\n",
 275                                   base, base + (uint32_t)ggtt->stolen_size);
 276                         base = 0;
 277                 }
 278         }
 279
 280         return base;
 281 }
 282
 283 void i915_gem_cleanup_stolen(struct drm_device *dev)
 284 {
 285         struct drm_i915_private *dev_priv = to_i915(dev);
 286
 287         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 288                 return;
 289
 290         drm_mm_takedown(&dev_priv->mm.stolen);
 291 }
 292
 293 static void g4x_get_stolen_reserved(struct drm_i915_private *dev_priv,
 294                                     unsigned long *base, unsigned long *size)
 295 {
 296         struct i915_ggtt *ggtt = &dev_priv->ggtt;
 297         uint32_t reg_val = I915_READ(IS_GM45(dev_priv) ?
 298                                      CTG_STOLEN_RESERVED :
 299                                      ELK_STOLEN_RESERVED);
 300         unsigned long stolen_top = dev_priv->mm.stolen_base +
 301                                    ggtt->stolen_size;
 302
 303         *base = (reg_val & G4X_STOLEN_RESERVED_ADDR2_MASK) << 16;
 304
 305         WARN_ON((reg_val & G4X_STOLEN_RESERVED_ADDR1_MASK) < *base);
 306
 307         /* On these platforms, the register doesn't have a size field, so the
 308          * size is the distance between the base and the top of the stolen
 309          * memory. We also have the genuine case where base is zero and there's
 310          * nothing reserved. */
 311         if (*base == 0)
 312                 *size = 0;
 313         else
 314                 *size = stolen_top - *base;
 315 }
 316
 317 static void gen6_get_stolen_reserved(struct drm_i915_private *dev_priv,
 318                                      unsigned long *base, unsigned long *size)
 319 {
 320         uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
 321
 322         *base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
 323
 324         switch (reg_val & GEN6_STOLEN_RESERVED_SIZE_MASK) {
 325         case GEN6_STOLEN_RESERVED_1M:
 326                 *size = 1024 * 1024;
 327                 break;
 328         case GEN6_STOLEN_RESERVED_512K:
 329                 *size = 512 * 1024;
 330                 break;
 331         case GEN6_STOLEN_RESERVED_256K:
 332                 *size = 256 * 1024;
 333                 break;
 334         case GEN6_STOLEN_RESERVED_128K:
 335                 *size = 128 * 1024;
 336                 break;
 337         default:
 338                 *size = 1024 * 1024;
 339                 MISSING_CASE(reg_val & GEN6_STOLEN_RESERVED_SIZE_MASK);
 340         }
 341 }
 342
 343 static void gen7_get_stolen_reserved(struct drm_i915_private *dev_priv,
 344                                      unsigned long *base, unsigned long *size)
 345 {
 346         uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
 347
 348         *base = reg_val & GEN7_STOLEN_RESERVED_ADDR_MASK;
 349
 350         switch (reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK) {
 351         case GEN7_STOLEN_RESERVED_1M:
 352                 *size = 1024 * 1024;
 353                 break;
 354         case GEN7_STOLEN_RESERVED_256K:
 355                 *size = 256 * 1024;
 356                 break;
 357         default:
 358                 *size = 1024 * 1024;
 359                 MISSING_CASE(reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK);
 360         }
 361 }
 362
 363 static void gen8_get_stolen_reserved(struct drm_i915_private *dev_priv,
 364                                      unsigned long *base, unsigned long *size)
 365 {
 366         uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
 367
 368         *base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
 369
 370         switch (reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK) {
 371         case GEN8_STOLEN_RESERVED_1M:
 372                 *size = 1024 * 1024;
 373                 break;
 374         case GEN8_STOLEN_RESERVED_2M:
 375                 *size = 2 * 1024 * 1024;
 376                 break;
 377         case GEN8_STOLEN_RESERVED_4M:
 378                 *size = 4 * 1024 * 1024;
 379                 break;
 380         case GEN8_STOLEN_RESERVED_8M:
 381                 *size = 8 * 1024 * 1024;
 382                 break;
 383         default:
 384                 *size = 8 * 1024 * 1024;
 385                 MISSING_CASE(reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK);
 386         }
 387 }
 388
 389 static void bdw_get_stolen_reserved(struct drm_i915_private *dev_priv,
 390                                     unsigned long *base, unsigned long *size)
 391 {
 392         struct i915_ggtt *ggtt = &dev_priv->ggtt;
 393         uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
 394         unsigned long stolen_top;
 395
 396         stolen_top = dev_priv->mm.stolen_base + ggtt->stolen_size;
 397
 398         *base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
 399
 400         /* On these platforms, the register doesn't have a size field, so the
 401          * size is the distance between the base and the top of the stolen
 402          * memory. We also have the genuine case where base is zero and there's
 403          * nothing reserved. */
 404         if (*base == 0)
 405                 *size = 0;
 406         else
 407                 *size = stolen_top - *base;
 408 }
 409
 410 int i915_gem_init_stolen(struct drm_i915_private *dev_priv)
 411 {
 412         struct i915_ggtt *ggtt = &dev_priv->ggtt;
 413         unsigned long reserved_total, reserved_base = 0, reserved_size;
 414         unsigned long stolen_top;
 415
 416         mutex_init(&dev_priv->mm.stolen_lock);
 417
 418 #ifdef CONFIG_INTEL_IOMMU
 419         if (intel_iommu_gfx_mapped && INTEL_GEN(dev_priv) < 8) {
 420                 DRM_INFO("DMAR active, disabling use of stolen memory\n");
 421                 return 0;
 422         }
 423 #endif
 424
 425         if (ggtt->stolen_size == 0)
 426                 return 0;
 427
 428         dev_priv->mm.stolen_base = i915_stolen_to_physical(dev_priv);
 429         if (dev_priv->mm.stolen_base == 0)
 430                 return 0;
 431
 432         stolen_top = dev_priv->mm.stolen_base + ggtt->stolen_size;
 433
 434         switch (INTEL_INFO(dev_priv)->gen) {
 435         case 2:
 436         case 3:
 437                 break;
 438         case 4:
 439                 if (IS_G4X(dev_priv))
 440                         g4x_get_stolen_reserved(dev_priv, &reserved_base,
 441                                                 &reserved_size);
 442                 break;
 443         case 5:
 444                 /* Assume the gen6 maximum for the older platforms. */
 445                 reserved_size = 1024 * 1024;
 446                 reserved_base = stolen_top - reserved_size;
 447                 break;
 448         case 6:
 449                 gen6_get_stolen_reserved(dev_priv, &reserved_base,
 450                                          &reserved_size);
 451                 break;
 452         case 7:
 453                 gen7_get_stolen_reserved(dev_priv, &reserved_base,
 454                                          &reserved_size);
 455                 break;
 456         default:
 457                 if (IS_BROADWELL(dev_priv) ||
 458                     IS_SKYLAKE(dev_priv) || IS_KABYLAKE(dev_priv))
 459                         bdw_get_stolen_reserved(dev_priv, &reserved_base,
 460                                                 &reserved_size);
 461                 else
 462                         gen8_get_stolen_reserved(dev_priv, &reserved_base,
 463                                                  &reserved_size);
 464                 break;
 465         }
 466
 467         /* It is possible for the reserved base to be zero, but the register
 468          * field for size doesn't have a zero option. */
 469         if (reserved_base == 0) {
 470                 reserved_size = 0;
 471                 reserved_base = stolen_top;
 472         }
 473
 474         if (reserved_base < dev_priv->mm.stolen_base ||
 475             reserved_base + reserved_size > stolen_top) {
 476                 DRM_DEBUG_KMS("Stolen reserved area [0x%08lx - 0x%08lx] outside stolen memory [0x%08lx - 0x%08lx]\n",
 477                               reserved_base, reserved_base + reserved_size,
 478                               dev_priv->mm.stolen_base, stolen_top);
 479                 return 0;
 480         }
 481
 482         ggtt->stolen_reserved_base = reserved_base;
 483         ggtt->stolen_reserved_size = reserved_size;
 484
 485         /* It is possible for the reserved area to end before the end of stolen
 486          * memory, so just consider the start. */
 487         reserved_total = stolen_top - reserved_base;
 488
 489         DRM_DEBUG_KMS("Memory reserved for graphics device: %zuK, usable: %luK\n",
 490                       ggtt->stolen_size >> 10,
 491                       (ggtt->stolen_size - reserved_total) >> 10);
 492
 493         ggtt->stolen_usable_size = ggtt->stolen_size - reserved_total;
 494
 495         /*
 496          * Basic memrange allocator for stolen space.
 497          *
 498          * TODO: Notice that some platforms require us to not use the first page
 499          * of the stolen memory but their BIOSes may still put the framebuffer
 500          * on the first page. So we don't reserve this page for now because of
 501          * that. Our current solution is to just prevent new nodes from being
 502          * inserted on the first page - see the check we have at
 503          * i915_gem_stolen_insert_node_in_range(). We may want to fix the fbcon
 504          * problem later.
 505          */
 506         drm_mm_init(&dev_priv->mm.stolen, 0, ggtt->stolen_usable_size);
 507
 508         return 0;
 509 }
 510
 511 static struct sg_table *
 512 i915_pages_create_for_stolen(struct drm_device *dev,
 513                              u32 offset, u32 size)
 514 {
 515         struct drm_i915_private *dev_priv = to_i915(dev);
 516         struct sg_table *st;
 517         struct scatterlist *sg;
 518
 519         GEM_BUG_ON(offset > dev_priv->ggtt.stolen_size - size);
 520
 521         /* We hide that we have no struct page backing our stolen object
 522          * by wrapping the contiguous physical allocation with a fake
 523          * dma mapping in a single scatterlist.
 524          */
 525
 526         st = kmalloc(sizeof(*st), GFP_KERNEL);
 527         if (st == NULL)
 528                 return ERR_PTR(-ENOMEM);
 529
 530         if (sg_alloc_table(st, 1, GFP_KERNEL)) {
 531                 kfree(st);
 532                 return ERR_PTR(-ENOMEM);
 533         }
 534
 535         sg = st->sgl;
 536         sg->offset = 0;
 537         sg->length = size;
 538
 539         sg_dma_address(sg) = (dma_addr_t)dev_priv->mm.stolen_base + offset;
 540         sg_dma_len(sg) = size;
 541
 542         return st;
 543 }
 544
 545 static struct sg_table *
 546 i915_gem_object_get_pages_stolen(struct drm_i915_gem_object *obj)
 547 {
 548         return i915_pages_create_for_stolen(obj->base.dev,
 549                                             obj->stolen->start,
 550                                             obj->stolen->size);
 551 }
 552
 553 static void i915_gem_object_put_pages_stolen(struct drm_i915_gem_object *obj,
 554                                              struct sg_table *pages)
 555 {
 556         /* Should only be called from i915_gem_object_release_stolen() */
 557         sg_free_table(pages);
 558         kfree(pages);
 559 }
 560
 561 static void
 562 i915_gem_object_release_stolen(struct drm_i915_gem_object *obj)
 563 {
 564         struct drm_i915_private *dev_priv = to_i915(obj->base.dev);
 565         struct drm_mm_node *stolen = fetch_and_zero(&obj->stolen);
 566
 567         GEM_BUG_ON(!stolen);
 568
 569         __i915_gem_object_unpin_pages(obj);
 570
 571         i915_gem_stolen_remove_node(dev_priv, stolen);
 572         kfree(stolen);
 573 }
 574
 575 static const struct drm_i915_gem_object_ops i915_gem_object_stolen_ops = {
 576         .get_pages = i915_gem_object_get_pages_stolen,
 577         .put_pages = i915_gem_object_put_pages_stolen,
 578         .release = i915_gem_object_release_stolen,
 579 };
 580
 581 static struct drm_i915_gem_object *
 582 _i915_gem_object_create_stolen(struct drm_i915_private *dev_priv,
 583                                struct drm_mm_node *stolen)
 584 {
 585         struct drm_i915_gem_object *obj;
 586
 587         obj = i915_gem_object_alloc(dev_priv);
 588         if (obj == NULL)
 589                 return NULL;
 590
 591         drm_gem_private_object_init(&dev_priv->drm, &obj->base, stolen->size);
 592         i915_gem_object_init(obj, &i915_gem_object_stolen_ops);
 593
 594         obj->stolen = stolen;
 595         obj->base.read_domains = I915_GEM_DOMAIN_CPU | I915_GEM_DOMAIN_GTT;
 596         obj->cache_level = HAS_LLC(dev_priv) ? I915_CACHE_LLC : I915_CACHE_NONE;
 597
 598         if (i915_gem_object_pin_pages(obj))
 599                 goto cleanup;
 600
 601         return obj;
 602
 603 cleanup:
 604         i915_gem_object_free(obj);
 605         return NULL;
 606 }
 607
 608 struct drm_i915_gem_object *
 609 i915_gem_object_create_stolen(struct drm_i915_private *dev_priv, u32 size)
 610 {
 611         struct drm_i915_gem_object *obj;
 612         struct drm_mm_node *stolen;
 613         int ret;
 614
 615         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 616                 return NULL;
 617
 618         if (size == 0)
 619                 return NULL;
 620
 621         stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
 622         if (!stolen)
 623                 return NULL;
 624
 625         ret = i915_gem_stolen_insert_node(dev_priv, stolen, size, 4096);
 626         if (ret) {
 627                 kfree(stolen);
 628                 return NULL;
 629         }
 630
 631         obj = _i915_gem_object_create_stolen(dev_priv, stolen);
 632         if (obj)
 633                 return obj;
 634
 635         i915_gem_stolen_remove_node(dev_priv, stolen);
 636         kfree(stolen);
 637         return NULL;
 638 }
 639
 640 struct drm_i915_gem_object *
 641 i915_gem_object_create_stolen_for_preallocated(struct drm_i915_private *dev_priv,
 642                                                u32 stolen_offset,
 643                                                u32 gtt_offset,
 644                                                u32 size)
 645 {
 646         struct i915_ggtt *ggtt = &dev_priv->ggtt;
 647         struct drm_i915_gem_object *obj;
 648         struct drm_mm_node *stolen;
 649         struct i915_vma *vma;
 650         int ret;
 651
 652         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 653                 return NULL;
 654
 655         lockdep_assert_held(&dev_priv->drm.struct_mutex);
 656
 657         DRM_DEBUG_KMS("creating preallocated stolen object: stolen_offset=%x, gtt_offset=%x, size=%x\n",
 658                         stolen_offset, gtt_offset, size);
 659
 660         /* KISS and expect everything to be page-aligned */
 661         if (WARN_ON(size == 0) || WARN_ON(size & 4095) ||
 662             WARN_ON(stolen_offset & 4095))
 663                 return NULL;
 664
 665         stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
 666         if (!stolen)
 667                 return NULL;
 668
 669         stolen->start = stolen_offset;
 670         stolen->size = size;
 671         mutex_lock(&dev_priv->mm.stolen_lock);
 672         ret = drm_mm_reserve_node(&dev_priv->mm.stolen, stolen);
 673         mutex_unlock(&dev_priv->mm.stolen_lock);
 674         if (ret) {
 675                 DRM_DEBUG_KMS("failed to allocate stolen space\n");
 676                 kfree(stolen);
 677                 return NULL;
 678         }
 679
 680         obj = _i915_gem_object_create_stolen(dev_priv, stolen);
 681         if (obj == NULL) {
 682                 DRM_DEBUG_KMS("failed to allocate stolen object\n");
 683                 i915_gem_stolen_remove_node(dev_priv, stolen);
 684                 kfree(stolen);
 685                 return NULL;
 686         }
 687
 688         /* Some objects just need physical mem from stolen space */
 689         if (gtt_offset == I915_GTT_OFFSET_NONE)
 690                 return obj;
 691
 692         ret = i915_gem_object_pin_pages(obj);
 693         if (ret)
 694                 goto err;
 695
 696         vma = i915_gem_obj_lookup_or_create_vma(obj, &ggtt->base, NULL);
 697         if (IS_ERR(vma)) {
 698                 ret = PTR_ERR(vma);
 699                 goto err_pages;
 700         }
 701
 702         /* To simplify the initialisation sequence between KMS and GTT,
 703          * we allow construction of the stolen object prior to
 704          * setting up the GTT space. The actual reservation will occur
 705          * later.
 706          */
 707         vma->node.start = gtt_offset;
 708         vma->node.size = size;
 709
 710         ret = drm_mm_reserve_node(&ggtt->base.mm, &vma->node);
 711         if (ret) {
 712                 DRM_DEBUG_KMS("failed to allocate stolen GTT space\n");
 713                 goto err_pages;
 714         }
 715
 716         vma->pages = obj->mm.pages;
 717         vma->flags |= I915_VMA_GLOBAL_BIND;
 718         __i915_vma_set_map_and_fenceable(vma);
 719         list_move_tail(&vma->vm_link, &ggtt->base.inactive_list);
 720         list_move_tail(&obj->global_link, &dev_priv->mm.bound_list);
 721         obj->bind_count++;
 722
 723         return obj;
 724
 725 err_pages:
 726         i915_gem_object_unpin_pages(obj);
 727 err:
 728         i915_gem_object_put(obj);
 729         return NULL;
 730 }