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 static unsigned long i915_stolen_to_physical(struct drm_device *dev)
  46 {
  47         struct drm_i915_private *dev_priv = dev->dev_private;
  48         struct resource *r;
  49         u32 base;
  50
  51         /* Almost universally we can find the Graphics Base of Stolen Memory
  52          * at offset 0x5c in the igfx configuration space. On a few (desktop)
  53          * machines this is also mirrored in the bridge device at different
  54          * locations, or in the MCHBAR. On gen2, the layout is again slightly
  55          * different with the Graphics Segment immediately following Top of
  56          * Memory (or Top of Usable DRAM). Note it appears that TOUD is only
  57          * reported by 865g, so we just use the top of memory as determined
  58          * by the e820 probe.
  59          *
  60          * XXX However gen2 requires an unavailable symbol.
  61          */
  62         base = 0;
  63         if (INTEL_INFO(dev)->gen >= 3) {
  64                 /* Read Graphics Base of Stolen Memory directly */
  65                 pci_read_config_dword(dev->pdev, 0x5c, &base);
  66                 base &= ~((1<<20) - 1);
  67         } else { /* GEN2 */
  68 #if 0
  69                 /* Stolen is immediately above Top of Memory */
  70                 base = max_low_pfn_mapped << PAGE_SHIFT;
  71 #endif
  72         }
  73
  74         if (base == 0)
  75                 return 0;
  76
  77         /* make sure we don't clobber the GTT if it's within stolen memory */
  78         if (INTEL_INFO(dev)->gen <= 4 && !IS_G33(dev) && !IS_G4X(dev)) {
  79                 struct {
  80                         u32 start, end;
  81                 } stolen[2] = {
  82                         { .start = base, .end = base + dev_priv->gtt.stolen_size, },
  83                         { .start = base, .end = base + dev_priv->gtt.stolen_size, },
  84                 };
  85                 u64 gtt_start, gtt_end;
  86
  87                 gtt_start = I915_READ(PGTBL_CTL);
  88                 if (IS_GEN4(dev))
  89                         gtt_start = (gtt_start & PGTBL_ADDRESS_LO_MASK) |
  90                                 (gtt_start & PGTBL_ADDRESS_HI_MASK) << 28;
  91                 else
  92                         gtt_start &= PGTBL_ADDRESS_LO_MASK;
  93                 gtt_end = gtt_start + gtt_total_entries(dev_priv->gtt) * 4;
  94
  95                 if (gtt_start >= stolen[0].start && gtt_start < stolen[0].end)
  96                         stolen[0].end = gtt_start;
  97                 if (gtt_end > stolen[1].start && gtt_end <= stolen[1].end)
  98                         stolen[1].start = gtt_end;
  99
 100                 /* pick the larger of the two chunks */
 101                 if (stolen[0].end - stolen[0].start >
 102                     stolen[1].end - stolen[1].start) {
 103                         base = stolen[0].start;
 104                         dev_priv->gtt.stolen_size = stolen[0].end - stolen[0].start;
 105                 } else {
 106                         base = stolen[1].start;
 107                         dev_priv->gtt.stolen_size = stolen[1].end - stolen[1].start;
 108                 }
 109
 110                 if (stolen[0].start != stolen[1].start ||
 111                     stolen[0].end != stolen[1].end) {
 112                         DRM_DEBUG_KMS("GTT within stolen memory at 0x%llx-0x%llx\n",
 113                                       (unsigned long long) gtt_start,
 114                                       (unsigned long long) gtt_end - 1);
 115                         DRM_DEBUG_KMS("Stolen memory adjusted to 0x%x-0x%x\n",
 116                                       base, base + (u32) dev_priv->gtt.stolen_size - 1);
 117                 }
 118         }
 119
 120
 121         /* Verify that nothing else uses this physical address. Stolen
 122          * memory should be reserved by the BIOS and hidden from the
 123          * kernel. So if the region is already marked as busy, something
 124          * is seriously wrong.
 125          */
 126         r = devm_request_mem_region(dev->dev, base, dev_priv->gtt.stolen_size,
 127                                     "Graphics Stolen Memory");
 128         if (r == NULL) {
 129                 /*
 130                  * One more attempt but this time requesting region from
 131                  * base + 1, as we have seen that this resolves the region
 132                  * conflict with the PCI Bus.
 133                  * This is a BIOS w/a: Some BIOS wrap stolen in the root
 134                  * PCI bus, but have an off-by-one error. Hence retry the
 135                  * reservation starting from 1 instead of 0.
 136                  */
 137                 r = devm_request_mem_region(dev->dev, base + 1,
 138                                             dev_priv->gtt.stolen_size - 1,
 139                                             "Graphics Stolen Memory");
 140                 if (r == NULL) {
 141                         DRM_ERROR("conflict detected with stolen region: [0x%08x - 0x%08x]\n",
 142                                   base, base + (uint32_t)dev_priv->gtt.stolen_size);
 143                         base = 0;
 144                 }
 145         }
 146
 147         return base;
 148 }
 149
 150 static int i915_setup_compression(struct drm_device *dev, int size)
 151 {
 152         struct drm_i915_private *dev_priv = dev->dev_private;
 153         struct drm_mm_node *compressed_fb, *uninitialized_var(compressed_llb);
 154         int ret;
 155
 156         compressed_fb = kzalloc(sizeof(*compressed_fb), GFP_KERNEL);
 157         if (!compressed_fb)
 158                 goto err_llb;
 159
 160         /* Try to over-allocate to reduce reallocations and fragmentation */
 161         ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_fb,
 162                                  size <<= 1, 4096, DRM_MM_SEARCH_DEFAULT);
 163         if (ret)
 164                 ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_fb,
 165                                          size >>= 1, 4096,
 166                                          DRM_MM_SEARCH_DEFAULT);
 167         if (ret)
 168                 goto err_llb;
 169
 170         if (HAS_PCH_SPLIT(dev))
 171                 I915_WRITE(ILK_DPFC_CB_BASE, compressed_fb->start);
 172         else if (IS_GM45(dev)) {
 173                 I915_WRITE(DPFC_CB_BASE, compressed_fb->start);
 174         } else {
 175                 compressed_llb = kzalloc(sizeof(*compressed_llb), GFP_KERNEL);
 176                 if (!compressed_llb)
 177                         goto err_fb;
 178
 179                 ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_llb,
 180                                          4096, 4096, DRM_MM_SEARCH_DEFAULT);
 181                 if (ret)
 182                         goto err_fb;
 183
 184                 dev_priv->fbc.compressed_llb = compressed_llb;
 185
 186                 I915_WRITE(FBC_CFB_BASE,
 187                            dev_priv->mm.stolen_base + compressed_fb->start);
 188                 I915_WRITE(FBC_LL_BASE,
 189                            dev_priv->mm.stolen_base + compressed_llb->start);
 190         }
 191
 192         dev_priv->fbc.compressed_fb = compressed_fb;
 193         dev_priv->fbc.size = size;
 194
 195         DRM_DEBUG_KMS("reserved %d bytes of contiguous stolen space for FBC\n",
 196                       size);
 197
 198         return 0;
 199
 200 err_fb:
 201         kfree(compressed_llb);
 202         drm_mm_remove_node(compressed_fb);
 203 err_llb:
 204         kfree(compressed_fb);
 205         pr_info_once("drm: not enough stolen space for compressed buffer (need %d more bytes), disabling. Hint: you may be able to increase stolen memory size in the BIOS to avoid this.\n", size);
 206         return -ENOSPC;
 207 }
 208
 209 int i915_gem_stolen_setup_compression(struct drm_device *dev, int size)
 210 {
 211         struct drm_i915_private *dev_priv = dev->dev_private;
 212
 213         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 214                 return -ENODEV;
 215
 216         if (size < dev_priv->fbc.size)
 217                 return 0;
 218
 219         /* Release any current block */
 220         i915_gem_stolen_cleanup_compression(dev);
 221
 222         return i915_setup_compression(dev, size);
 223 }
 224
 225 void i915_gem_stolen_cleanup_compression(struct drm_device *dev)
 226 {
 227         struct drm_i915_private *dev_priv = dev->dev_private;
 228
 229         if (dev_priv->fbc.size == 0)
 230                 return;
 231
 232         if (dev_priv->fbc.compressed_fb) {
 233                 drm_mm_remove_node(dev_priv->fbc.compressed_fb);
 234                 kfree(dev_priv->fbc.compressed_fb);
 235         }
 236
 237         if (dev_priv->fbc.compressed_llb) {
 238                 drm_mm_remove_node(dev_priv->fbc.compressed_llb);
 239                 kfree(dev_priv->fbc.compressed_llb);
 240         }
 241
 242         dev_priv->fbc.size = 0;
 243 }
 244
 245 void i915_gem_cleanup_stolen(struct drm_device *dev)
 246 {
 247         struct drm_i915_private *dev_priv = dev->dev_private;
 248
 249         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 250                 return;
 251
 252         i915_gem_stolen_cleanup_compression(dev);
 253         drm_mm_takedown(&dev_priv->mm.stolen);
 254 }
 255
 256 int i915_gem_init_stolen(struct drm_device *dev)
 257 {
 258         struct drm_i915_private *dev_priv = dev->dev_private;
 259         int bios_reserved = 0;
 260
 261 #ifdef CONFIG_INTEL_IOMMU
 262         if (intel_iommu_gfx_mapped && INTEL_INFO(dev)->gen < 8) {
 263                 DRM_INFO("DMAR active, disabling use of stolen memory\n");
 264                 return 0;
 265         }
 266 #endif
 267
 268         if (dev_priv->gtt.stolen_size == 0)
 269                 return 0;
 270
 271         dev_priv->mm.stolen_base = i915_stolen_to_physical(dev);
 272         if (dev_priv->mm.stolen_base == 0)
 273                 return 0;
 274
 275         DRM_DEBUG_KMS("found %zd bytes of stolen memory at %08lx\n",
 276                       dev_priv->gtt.stolen_size, dev_priv->mm.stolen_base);
 277
 278         if (IS_VALLEYVIEW(dev))
 279                 bios_reserved = 1024*1024; /* top 1M on VLV/BYT */
 280
 281         if (WARN_ON(bios_reserved > dev_priv->gtt.stolen_size))
 282                 return 0;
 283
 284         /* Basic memrange allocator for stolen space */
 285         drm_mm_init(&dev_priv->mm.stolen, 0, dev_priv->gtt.stolen_size -
 286                     bios_reserved);
 287
 288         return 0;
 289 }
 290
 291 static struct sg_table *
 292 i915_pages_create_for_stolen(struct drm_device *dev,
 293                              u32 offset, u32 size)
 294 {
 295         struct drm_i915_private *dev_priv = dev->dev_private;
 296         struct sg_table *st;
 297         struct scatterlist *sg;
 298
 299         DRM_DEBUG_DRIVER("offset=0x%x, size=%d\n", offset, size);
 300         BUG_ON(offset > dev_priv->gtt.stolen_size - size);
 301
 302         /* We hide that we have no struct page backing our stolen object
 303          * by wrapping the contiguous physical allocation with a fake
 304          * dma mapping in a single scatterlist.
 305          */
 306
 307         st = kmalloc(sizeof(*st), GFP_KERNEL);
 308         if (st == NULL)
 309                 return NULL;
 310
 311         if (sg_alloc_table(st, 1, GFP_KERNEL)) {
 312                 kfree(st);
 313                 return NULL;
 314         }
 315
 316         sg = st->sgl;
 317         sg->offset = 0;
 318         sg->length = size;
 319
 320         sg_dma_address(sg) = (dma_addr_t)dev_priv->mm.stolen_base + offset;
 321         sg_dma_len(sg) = size;
 322
 323         return st;
 324 }
 325
 326 static int i915_gem_object_get_pages_stolen(struct drm_i915_gem_object *obj)
 327 {
 328         BUG();
 329         return -EINVAL;
 330 }
 331
 332 static void i915_gem_object_put_pages_stolen(struct drm_i915_gem_object *obj)
 333 {
 334         /* Should only be called during free */
 335         sg_free_table(obj->pages);
 336         kfree(obj->pages);
 337 }
 338
 339 static const struct drm_i915_gem_object_ops i915_gem_object_stolen_ops = {
 340         .get_pages = i915_gem_object_get_pages_stolen,
 341         .put_pages = i915_gem_object_put_pages_stolen,
 342 };
 343
 344 static struct drm_i915_gem_object *
 345 _i915_gem_object_create_stolen(struct drm_device *dev,
 346                                struct drm_mm_node *stolen)
 347 {
 348         struct drm_i915_gem_object *obj;
 349
 350         obj = i915_gem_object_alloc(dev);
 351         if (obj == NULL)
 352                 return NULL;
 353
 354         drm_gem_private_object_init(dev, &obj->base, stolen->size);
 355         i915_gem_object_init(obj, &i915_gem_object_stolen_ops);
 356
 357         obj->pages = i915_pages_create_for_stolen(dev,
 358                                                   stolen->start, stolen->size);
 359         if (obj->pages == NULL)
 360                 goto cleanup;
 361
 362         obj->has_dma_mapping = true;
 363         i915_gem_object_pin_pages(obj);
 364         obj->stolen = stolen;
 365
 366         obj->base.read_domains = I915_GEM_DOMAIN_CPU | I915_GEM_DOMAIN_GTT;
 367         obj->cache_level = HAS_LLC(dev) ? I915_CACHE_LLC : I915_CACHE_NONE;
 368
 369         return obj;
 370
 371 cleanup:
 372         i915_gem_object_free(obj);
 373         return NULL;
 374 }
 375
 376 struct drm_i915_gem_object *
 377 i915_gem_object_create_stolen(struct drm_device *dev, u32 size)
 378 {
 379         struct drm_i915_private *dev_priv = dev->dev_private;
 380         struct drm_i915_gem_object *obj;
 381         struct drm_mm_node *stolen;
 382         int ret;
 383
 384         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 385                 return NULL;
 386
 387         DRM_DEBUG_KMS("creating stolen object: size=%x\n", size);
 388         if (size == 0)
 389                 return NULL;
 390
 391         stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
 392         if (!stolen)
 393                 return NULL;
 394
 395         ret = drm_mm_insert_node(&dev_priv->mm.stolen, stolen, size,
 396                                  4096, DRM_MM_SEARCH_DEFAULT);
 397         if (ret) {
 398                 kfree(stolen);
 399                 return NULL;
 400         }
 401
 402         obj = _i915_gem_object_create_stolen(dev, stolen);
 403         if (obj)
 404                 return obj;
 405
 406         drm_mm_remove_node(stolen);
 407         kfree(stolen);
 408         return NULL;
 409 }
 410
 411 struct drm_i915_gem_object *
 412 i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
 413                                                u32 stolen_offset,
 414                                                u32 gtt_offset,
 415                                                u32 size)
 416 {
 417         struct drm_i915_private *dev_priv = dev->dev_private;
 418         struct i915_address_space *ggtt = &dev_priv->gtt.base;
 419         struct drm_i915_gem_object *obj;
 420         struct drm_mm_node *stolen;
 421         struct i915_vma *vma;
 422         int ret;
 423
 424         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 425                 return NULL;
 426
 427         DRM_DEBUG_KMS("creating preallocated stolen object: stolen_offset=%x, gtt_offset=%x, size=%x\n",
 428                         stolen_offset, gtt_offset, size);
 429
 430         /* KISS and expect everything to be page-aligned */
 431         BUG_ON(stolen_offset & 4095);
 432         BUG_ON(size & 4095);
 433
 434         if (WARN_ON(size == 0))
 435                 return NULL;
 436
 437         stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
 438         if (!stolen)
 439                 return NULL;
 440
 441         stolen->start = stolen_offset;
 442         stolen->size = size;
 443         ret = drm_mm_reserve_node(&dev_priv->mm.stolen, stolen);
 444         if (ret) {
 445                 DRM_DEBUG_KMS("failed to allocate stolen space\n");
 446                 kfree(stolen);
 447                 return NULL;
 448         }
 449
 450         obj = _i915_gem_object_create_stolen(dev, stolen);
 451         if (obj == NULL) {
 452                 DRM_DEBUG_KMS("failed to allocate stolen object\n");
 453                 drm_mm_remove_node(stolen);
 454                 kfree(stolen);
 455                 return NULL;
 456         }
 457
 458         /* Some objects just need physical mem from stolen space */
 459         if (gtt_offset == I915_GTT_OFFSET_NONE)
 460                 return obj;
 461
 462         vma = i915_gem_obj_lookup_or_create_vma(obj, ggtt);
 463         if (IS_ERR(vma)) {
 464                 ret = PTR_ERR(vma);
 465                 goto err_out;
 466         }
 467
 468         /* To simplify the initialisation sequence between KMS and GTT,
 469          * we allow construction of the stolen object prior to
 470          * setting up the GTT space. The actual reservation will occur
 471          * later.
 472          */
 473         vma->node.start = gtt_offset;
 474         vma->node.size = size;
 475         if (drm_mm_initialized(&ggtt->mm)) {
 476                 ret = drm_mm_reserve_node(&ggtt->mm, &vma->node);
 477                 if (ret) {
 478                         DRM_DEBUG_KMS("failed to allocate stolen GTT space\n");
 479                         goto err_vma;
 480                 }
 481         }
 482
 483         obj->has_global_gtt_mapping = 1;
 484
 485         list_add_tail(&obj->global_list, &dev_priv->mm.bound_list);
 486         list_add_tail(&vma->mm_list, &ggtt->inactive_list);
 487         i915_gem_object_pin_pages(obj);
 488
 489         return obj;
 490
 491 err_vma:
 492         i915_gem_vma_destroy(vma);
 493 err_out:
 494         drm_mm_remove_node(stolen);
 495         kfree(stolen);
 496         drm_gem_object_unreference(&obj->base);
 497         return NULL;
 498 }
 499
 500 void
 501 i915_gem_object_release_stolen(struct drm_i915_gem_object *obj)
 502 {
 503         if (obj->stolen) {
 504                 drm_mm_remove_node(obj->stolen);
 505                 kfree(obj->stolen);
 506                 obj->stolen = NULL;
 507         }
 508 }