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(struct drm_i915_private *dev_priv,
  46                                 struct drm_mm_node *node, u64 size,
  47                                 unsigned alignment)
  48 {
  49         int ret;
  50
  51         if (!drm_mm_initialized(&dev_priv->mm.stolen))
  52                 return -ENODEV;
  53
  54         mutex_lock(&dev_priv->mm.stolen_lock);
  55         ret = drm_mm_insert_node(&dev_priv->mm.stolen, node, size, alignment,
  56                                  DRM_MM_SEARCH_DEFAULT);
  57         mutex_unlock(&dev_priv->mm.stolen_lock);
  58
  59         return ret;
  60 }
  61
  62 void i915_gem_stolen_remove_node(struct drm_i915_private *dev_priv,
  63                                  struct drm_mm_node *node)
  64 {
  65         mutex_lock(&dev_priv->mm.stolen_lock);
  66         drm_mm_remove_node(node);
  67         mutex_unlock(&dev_priv->mm.stolen_lock);
  68 }
  69
  70 static unsigned long i915_stolen_to_physical(struct drm_device *dev)
  71 {
  72         struct drm_i915_private *dev_priv = dev->dev_private;
  73         struct resource *r;
  74         u32 base;
  75
  76         /* Almost universally we can find the Graphics Base of Stolen Memory
  77          * at offset 0x5c in the igfx configuration space. On a few (desktop)
  78          * machines this is also mirrored in the bridge device at different
  79          * locations, or in the MCHBAR. On gen2, the layout is again slightly
  80          * different with the Graphics Segment immediately following Top of
  81          * Memory (or Top of Usable DRAM). Note it appears that TOUD is only
  82          * reported by 865g, so we just use the top of memory as determined
  83          * by the e820 probe.
  84          *
  85          * XXX However gen2 requires an unavailable symbol.
  86          */
  87         base = 0;
  88         if (INTEL_INFO(dev)->gen >= 3) {
  89                 /* Read Graphics Base of Stolen Memory directly */
  90                 pci_read_config_dword(dev->pdev, 0x5c, &base);
  91                 base &= ~((1<<20) - 1);
  92         } else { /* GEN2 */
  93 #if 0
  94                 /* Stolen is immediately above Top of Memory */
  95                 base = max_low_pfn_mapped << PAGE_SHIFT;
  96 #endif
  97         }
  98
  99         if (base == 0)
 100                 return 0;
 101
 102         /* make sure we don't clobber the GTT if it's within stolen memory */
 103         if (INTEL_INFO(dev)->gen <= 4 && !IS_G33(dev) && !IS_G4X(dev)) {
 104                 struct {
 105                         u32 start, end;
 106                 } stolen[2] = {
 107                         { .start = base, .end = base + dev_priv->gtt.stolen_size, },
 108                         { .start = base, .end = base + dev_priv->gtt.stolen_size, },
 109                 };
 110                 u64 gtt_start, gtt_end;
 111
 112                 gtt_start = I915_READ(PGTBL_CTL);
 113                 if (IS_GEN4(dev))
 114                         gtt_start = (gtt_start & PGTBL_ADDRESS_LO_MASK) |
 115                                 (gtt_start & PGTBL_ADDRESS_HI_MASK) << 28;
 116                 else
 117                         gtt_start &= PGTBL_ADDRESS_LO_MASK;
 118                 gtt_end = gtt_start + gtt_total_entries(dev_priv->gtt) * 4;
 119
 120                 if (gtt_start >= stolen[0].start && gtt_start < stolen[0].end)
 121                         stolen[0].end = gtt_start;
 122                 if (gtt_end > stolen[1].start && gtt_end <= stolen[1].end)
 123                         stolen[1].start = gtt_end;
 124
 125                 /* pick the larger of the two chunks */
 126                 if (stolen[0].end - stolen[0].start >
 127                     stolen[1].end - stolen[1].start) {
 128                         base = stolen[0].start;
 129                         dev_priv->gtt.stolen_size = stolen[0].end - stolen[0].start;
 130                 } else {
 131                         base = stolen[1].start;
 132                         dev_priv->gtt.stolen_size = stolen[1].end - stolen[1].start;
 133                 }
 134
 135                 if (stolen[0].start != stolen[1].start ||
 136                     stolen[0].end != stolen[1].end) {
 137                         DRM_DEBUG_KMS("GTT within stolen memory at 0x%llx-0x%llx\n",
 138                                       (unsigned long long) gtt_start,
 139                                       (unsigned long long) gtt_end - 1);
 140                         DRM_DEBUG_KMS("Stolen memory adjusted to 0x%x-0x%x\n",
 141                                       base, base + (u32) dev_priv->gtt.stolen_size - 1);
 142                 }
 143         }
 144
 145
 146         /* Verify that nothing else uses this physical address. Stolen
 147          * memory should be reserved by the BIOS and hidden from the
 148          * kernel. So if the region is already marked as busy, something
 149          * is seriously wrong.
 150          */
 151         r = devm_request_mem_region(dev->dev, base, dev_priv->gtt.stolen_size,
 152                                     "Graphics Stolen Memory");
 153         if (r == NULL) {
 154                 /*
 155                  * One more attempt but this time requesting region from
 156                  * base + 1, as we have seen that this resolves the region
 157                  * conflict with the PCI Bus.
 158                  * This is a BIOS w/a: Some BIOS wrap stolen in the root
 159                  * PCI bus, but have an off-by-one error. Hence retry the
 160                  * reservation starting from 1 instead of 0.
 161                  */
 162                 r = devm_request_mem_region(dev->dev, base + 1,
 163                                             dev_priv->gtt.stolen_size - 1,
 164                                             "Graphics Stolen Memory");
 165                 /*
 166                  * GEN3 firmware likes to smash pci bridges into the stolen
 167                  * range. Apparently this works.
 168                  */
 169                 if (r == NULL && !IS_GEN3(dev)) {
 170                         DRM_ERROR("conflict detected with stolen region: [0x%08x - 0x%08x]\n",
 171                                   base, base + (uint32_t)dev_priv->gtt.stolen_size);
 172                         base = 0;
 173                 }
 174         }
 175
 176         return base;
 177 }
 178
 179 void i915_gem_cleanup_stolen(struct drm_device *dev)
 180 {
 181         struct drm_i915_private *dev_priv = dev->dev_private;
 182
 183         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 184                 return;
 185
 186         drm_mm_takedown(&dev_priv->mm.stolen);
 187 }
 188
 189 static void gen6_get_stolen_reserved(struct drm_i915_private *dev_priv,
 190                                      unsigned long *base, unsigned long *size)
 191 {
 192         uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
 193
 194         *base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
 195
 196         switch (reg_val & GEN6_STOLEN_RESERVED_SIZE_MASK) {
 197         case GEN6_STOLEN_RESERVED_1M:
 198                 *size = 1024 * 1024;
 199                 break;
 200         case GEN6_STOLEN_RESERVED_512K:
 201                 *size = 512 * 1024;
 202                 break;
 203         case GEN6_STOLEN_RESERVED_256K:
 204                 *size = 256 * 1024;
 205                 break;
 206         case GEN6_STOLEN_RESERVED_128K:
 207                 *size = 128 * 1024;
 208                 break;
 209         default:
 210                 *size = 1024 * 1024;
 211                 MISSING_CASE(reg_val & GEN6_STOLEN_RESERVED_SIZE_MASK);
 212         }
 213 }
 214
 215 static void gen7_get_stolen_reserved(struct drm_i915_private *dev_priv,
 216                                      unsigned long *base, unsigned long *size)
 217 {
 218         uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
 219
 220         *base = reg_val & GEN7_STOLEN_RESERVED_ADDR_MASK;
 221
 222         switch (reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK) {
 223         case GEN7_STOLEN_RESERVED_1M:
 224                 *size = 1024 * 1024;
 225                 break;
 226         case GEN7_STOLEN_RESERVED_256K:
 227                 *size = 256 * 1024;
 228                 break;
 229         default:
 230                 *size = 1024 * 1024;
 231                 MISSING_CASE(reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK);
 232         }
 233 }
 234
 235 static void gen8_get_stolen_reserved(struct drm_i915_private *dev_priv,
 236                                      unsigned long *base, unsigned long *size)
 237 {
 238         uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
 239
 240         *base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
 241
 242         switch (reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK) {
 243         case GEN8_STOLEN_RESERVED_1M:
 244                 *size = 1024 * 1024;
 245                 break;
 246         case GEN8_STOLEN_RESERVED_2M:
 247                 *size = 2 * 1024 * 1024;
 248                 break;
 249         case GEN8_STOLEN_RESERVED_4M:
 250                 *size = 4 * 1024 * 1024;
 251                 break;
 252         case GEN8_STOLEN_RESERVED_8M:
 253                 *size = 8 * 1024 * 1024;
 254                 break;
 255         default:
 256                 *size = 8 * 1024 * 1024;
 257                 MISSING_CASE(reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK);
 258         }
 259 }
 260
 261 static void bdw_get_stolen_reserved(struct drm_i915_private *dev_priv,
 262                                     unsigned long *base, unsigned long *size)
 263 {
 264         uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
 265         unsigned long stolen_top;
 266
 267         stolen_top = dev_priv->mm.stolen_base + dev_priv->gtt.stolen_size;
 268
 269         *base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
 270
 271         /* On these platforms, the register doesn't have a size field, so the
 272          * size is the distance between the base and the top of the stolen
 273          * memory. We also have the genuine case where base is zero and there's
 274          * nothing reserved. */
 275         if (*base == 0)
 276                 *size = 0;
 277         else
 278                 *size = stolen_top - *base;
 279 }
 280
 281 int i915_gem_init_stolen(struct drm_device *dev)
 282 {
 283         struct drm_i915_private *dev_priv = dev->dev_private;
 284         unsigned long reserved_total, reserved_base, reserved_size;
 285         unsigned long stolen_top;
 286
 287         mutex_init(&dev_priv->mm.stolen_lock);
 288
 289 #ifdef CONFIG_INTEL_IOMMU
 290         if (intel_iommu_gfx_mapped && INTEL_INFO(dev)->gen < 8) {
 291                 DRM_INFO("DMAR active, disabling use of stolen memory\n");
 292                 return 0;
 293         }
 294 #endif
 295
 296         if (dev_priv->gtt.stolen_size == 0)
 297                 return 0;
 298
 299         dev_priv->mm.stolen_base = i915_stolen_to_physical(dev);
 300         if (dev_priv->mm.stolen_base == 0)
 301                 return 0;
 302
 303         stolen_top = dev_priv->mm.stolen_base + dev_priv->gtt.stolen_size;
 304
 305         switch (INTEL_INFO(dev_priv)->gen) {
 306         case 2:
 307         case 3:
 308         case 4:
 309         case 5:
 310                 /* Assume the gen6 maximum for the older platforms. */
 311                 reserved_size = 1024 * 1024;
 312                 reserved_base = stolen_top - reserved_size;
 313                 break;
 314         case 6:
 315                 gen6_get_stolen_reserved(dev_priv, &reserved_base,
 316                                          &reserved_size);
 317                 break;
 318         case 7:
 319                 gen7_get_stolen_reserved(dev_priv, &reserved_base,
 320                                          &reserved_size);
 321                 break;
 322         default:
 323                 if (IS_BROADWELL(dev_priv) || IS_SKYLAKE(dev_priv))
 324                         bdw_get_stolen_reserved(dev_priv, &reserved_base,
 325                                                 &reserved_size);
 326                 else
 327                         gen8_get_stolen_reserved(dev_priv, &reserved_base,
 328                                                  &reserved_size);
 329                 break;
 330         }
 331
 332         /* It is possible for the reserved base to be zero, but the register
 333          * field for size doesn't have a zero option. */
 334         if (reserved_base == 0) {
 335                 reserved_size = 0;
 336                 reserved_base = stolen_top;
 337         }
 338
 339         if (reserved_base < dev_priv->mm.stolen_base ||
 340             reserved_base + reserved_size > stolen_top) {
 341                 DRM_DEBUG_KMS("Stolen reserved area [0x%08lx - 0x%08lx] outside stolen memory [0x%08lx - 0x%08lx]\n",
 342                               reserved_base, reserved_base + reserved_size,
 343                               dev_priv->mm.stolen_base, stolen_top);
 344                 return 0;
 345         }
 346
 347         /* It is possible for the reserved area to end before the end of stolen
 348          * memory, so just consider the start. */
 349         reserved_total = stolen_top - reserved_base;
 350
 351         DRM_DEBUG_KMS("Memory reserved for graphics device: %zuK, usable: %luK\n",
 352                       dev_priv->gtt.stolen_size >> 10,
 353                       (dev_priv->gtt.stolen_size - reserved_total) >> 10);
 354
 355         /* Basic memrange allocator for stolen space */
 356         drm_mm_init(&dev_priv->mm.stolen, 0, dev_priv->gtt.stolen_size -
 357                     reserved_total);
 358
 359         return 0;
 360 }
 361
 362 static struct sg_table *
 363 i915_pages_create_for_stolen(struct drm_device *dev,
 364                              u32 offset, u32 size)
 365 {
 366         struct drm_i915_private *dev_priv = dev->dev_private;
 367         struct sg_table *st;
 368         struct scatterlist *sg;
 369
 370         DRM_DEBUG_DRIVER("offset=0x%x, size=%d\n", offset, size);
 371         BUG_ON(offset > dev_priv->gtt.stolen_size - size);
 372
 373         /* We hide that we have no struct page backing our stolen object
 374          * by wrapping the contiguous physical allocation with a fake
 375          * dma mapping in a single scatterlist.
 376          */
 377
 378         st = kmalloc(sizeof(*st), GFP_KERNEL);
 379         if (st == NULL)
 380                 return NULL;
 381
 382         if (sg_alloc_table(st, 1, GFP_KERNEL)) {
 383                 kfree(st);
 384                 return NULL;
 385         }
 386
 387         sg = st->sgl;
 388         sg->offset = 0;
 389         sg->length = size;
 390
 391         sg_dma_address(sg) = (dma_addr_t)dev_priv->mm.stolen_base + offset;
 392         sg_dma_len(sg) = size;
 393
 394         return st;
 395 }
 396
 397 static int i915_gem_object_get_pages_stolen(struct drm_i915_gem_object *obj)
 398 {
 399         BUG();
 400         return -EINVAL;
 401 }
 402
 403 static void i915_gem_object_put_pages_stolen(struct drm_i915_gem_object *obj)
 404 {
 405         /* Should only be called during free */
 406         sg_free_table(obj->pages);
 407         kfree(obj->pages);
 408 }
 409
 410
 411 static void
 412 i915_gem_object_release_stolen(struct drm_i915_gem_object *obj)
 413 {
 414         struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
 415
 416         if (obj->stolen) {
 417                 i915_gem_stolen_remove_node(dev_priv, obj->stolen);
 418                 kfree(obj->stolen);
 419                 obj->stolen = NULL;
 420         }
 421 }
 422 static const struct drm_i915_gem_object_ops i915_gem_object_stolen_ops = {
 423         .get_pages = i915_gem_object_get_pages_stolen,
 424         .put_pages = i915_gem_object_put_pages_stolen,
 425         .release = i915_gem_object_release_stolen,
 426 };
 427
 428 static struct drm_i915_gem_object *
 429 _i915_gem_object_create_stolen(struct drm_device *dev,
 430                                struct drm_mm_node *stolen)
 431 {
 432         struct drm_i915_gem_object *obj;
 433
 434         obj = i915_gem_object_alloc(dev);
 435         if (obj == NULL)
 436                 return NULL;
 437
 438         drm_gem_private_object_init(dev, &obj->base, stolen->size);
 439         i915_gem_object_init(obj, &i915_gem_object_stolen_ops);
 440
 441         obj->pages = i915_pages_create_for_stolen(dev,
 442                                                   stolen->start, stolen->size);
 443         if (obj->pages == NULL)
 444                 goto cleanup;
 445
 446         i915_gem_object_pin_pages(obj);
 447         obj->stolen = stolen;
 448
 449         obj->base.read_domains = I915_GEM_DOMAIN_CPU | I915_GEM_DOMAIN_GTT;
 450         obj->cache_level = HAS_LLC(dev) ? I915_CACHE_LLC : I915_CACHE_NONE;
 451
 452         return obj;
 453
 454 cleanup:
 455         i915_gem_object_free(obj);
 456         return NULL;
 457 }
 458
 459 struct drm_i915_gem_object *
 460 i915_gem_object_create_stolen(struct drm_device *dev, u32 size)
 461 {
 462         struct drm_i915_private *dev_priv = dev->dev_private;
 463         struct drm_i915_gem_object *obj;
 464         struct drm_mm_node *stolen;
 465         int ret;
 466
 467         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 468                 return NULL;
 469
 470         DRM_DEBUG_KMS("creating stolen object: size=%x\n", size);
 471         if (size == 0)
 472                 return NULL;
 473
 474         stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
 475         if (!stolen)
 476                 return NULL;
 477
 478         ret = i915_gem_stolen_insert_node(dev_priv, stolen, size, 4096);
 479         if (ret) {
 480                 kfree(stolen);
 481                 return NULL;
 482         }
 483
 484         obj = _i915_gem_object_create_stolen(dev, stolen);
 485         if (obj)
 486                 return obj;
 487
 488         i915_gem_stolen_remove_node(dev_priv, stolen);
 489         kfree(stolen);
 490         return NULL;
 491 }
 492
 493 struct drm_i915_gem_object *
 494 i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
 495                                                u32 stolen_offset,
 496                                                u32 gtt_offset,
 497                                                u32 size)
 498 {
 499         struct drm_i915_private *dev_priv = dev->dev_private;
 500         struct i915_address_space *ggtt = &dev_priv->gtt.base;
 501         struct drm_i915_gem_object *obj;
 502         struct drm_mm_node *stolen;
 503         struct i915_vma *vma;
 504         int ret;
 505
 506         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 507                 return NULL;
 508
 509         DRM_DEBUG_KMS("creating preallocated stolen object: stolen_offset=%x, gtt_offset=%x, size=%x\n",
 510                         stolen_offset, gtt_offset, size);
 511
 512         /* KISS and expect everything to be page-aligned */
 513         if (WARN_ON(size == 0) || WARN_ON(size & 4095) ||
 514             WARN_ON(stolen_offset & 4095))
 515                 return NULL;
 516
 517         stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
 518         if (!stolen)
 519                 return NULL;
 520
 521         stolen->start = stolen_offset;
 522         stolen->size = size;
 523         mutex_lock(&dev_priv->mm.stolen_lock);
 524         ret = drm_mm_reserve_node(&dev_priv->mm.stolen, stolen);
 525         mutex_unlock(&dev_priv->mm.stolen_lock);
 526         if (ret) {
 527                 DRM_DEBUG_KMS("failed to allocate stolen space\n");
 528                 kfree(stolen);
 529                 return NULL;
 530         }
 531
 532         obj = _i915_gem_object_create_stolen(dev, stolen);
 533         if (obj == NULL) {
 534                 DRM_DEBUG_KMS("failed to allocate stolen object\n");
 535                 i915_gem_stolen_remove_node(dev_priv, stolen);
 536                 kfree(stolen);
 537                 return NULL;
 538         }
 539
 540         /* Some objects just need physical mem from stolen space */
 541         if (gtt_offset == I915_GTT_OFFSET_NONE)
 542                 return obj;
 543
 544         vma = i915_gem_obj_lookup_or_create_vma(obj, ggtt);
 545         if (IS_ERR(vma)) {
 546                 ret = PTR_ERR(vma);
 547                 goto err_out;
 548         }
 549
 550         /* To simplify the initialisation sequence between KMS and GTT,
 551          * we allow construction of the stolen object prior to
 552          * setting up the GTT space. The actual reservation will occur
 553          * later.
 554          */
 555         vma->node.start = gtt_offset;
 556         vma->node.size = size;
 557         if (drm_mm_initialized(&ggtt->mm)) {
 558                 ret = drm_mm_reserve_node(&ggtt->mm, &vma->node);
 559                 if (ret) {
 560                         DRM_DEBUG_KMS("failed to allocate stolen GTT space\n");
 561                         goto err_vma;
 562                 }
 563         }
 564
 565         vma->bound |= GLOBAL_BIND;
 566
 567         list_add_tail(&obj->global_list, &dev_priv->mm.bound_list);
 568         list_add_tail(&vma->mm_list, &ggtt->inactive_list);
 569         i915_gem_object_pin_pages(obj);
 570
 571         return obj;
 572
 573 err_vma:
 574         i915_gem_vma_destroy(vma);
 575 err_out:
 576         i915_gem_stolen_remove_node(dev_priv, stolen);
 577         kfree(stolen);
 578         drm_gem_object_unreference(&obj->base);
 579         return NULL;
 580 }