sys/dev/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         u32 base;
  49
  50         /* Almost universally we can find the Graphics Base of Stolen Memory
  51          * at offset 0x5c in the igfx configuration space. On a few (desktop)
  52          * machines this is also mirrored in the bridge device at different
  53          * locations, or in the MCHBAR. On gen2, the layout is again slightly
  54          * different with the Graphics Segment immediately following Top of
  55          * Memory (or Top of Usable DRAM). Note it appears that TOUD is only
  56          * reported by 865g, so we just use the top of memory as determined
  57          * by the e820 probe.
  58          *
  59          * XXX However gen2 requires an unavailable symbol.
  60          */
  61         base = 0;
  62         if (INTEL_INFO(dev)->gen >= 3) {
  63                 /* Read Graphics Base of Stolen Memory directly */
  64                 pci_read_config_dword(dev->pdev, 0x5c, &base);
  65                 base &= ~((1<<20) - 1);
  66         } else { /* GEN2 */
  67 #if 0
  68                 /* Stolen is immediately above Top of Memory */
  69                 base = max_low_pfn_mapped << PAGE_SHIFT;
  70 #endif
  71         }
  72
  73         if (base == 0)
  74                 return 0;
  75
  76         /* make sure we don't clobber the GTT if it's within stolen memory */
  77         if (INTEL_INFO(dev)->gen <= 4 && !IS_G33(dev) && !IS_G4X(dev)) {
  78                 struct {
  79                         u32 start, end;
  80                 } stolen[2] = {
  81                         { .start = base, .end = base + dev_priv->gtt.stolen_size, },
  82                         { .start = base, .end = base + dev_priv->gtt.stolen_size, },
  83                 };
  84                 u64 gtt_start, gtt_end;
  85
  86                 gtt_start = I915_READ(PGTBL_CTL);
  87                 if (IS_GEN4(dev))
  88                         gtt_start = (gtt_start & PGTBL_ADDRESS_LO_MASK) |
  89                                 (gtt_start & PGTBL_ADDRESS_HI_MASK) << 28;
  90                 else
  91                         gtt_start &= PGTBL_ADDRESS_LO_MASK;
  92                 gtt_end = gtt_start + gtt_total_entries(dev_priv->gtt) * 4;
  93
  94                 if (gtt_start >= stolen[0].start && gtt_start < stolen[0].end)
  95                         stolen[0].end = gtt_start;
  96                 if (gtt_end > stolen[1].start && gtt_end <= stolen[1].end)
  97                         stolen[1].start = gtt_end;
  98
  99                 /* pick the larger of the two chunks */
 100                 if (stolen[0].end - stolen[0].start >
 101                     stolen[1].end - stolen[1].start) {
 102                         base = stolen[0].start;
 103                         dev_priv->gtt.stolen_size = stolen[0].end - stolen[0].start;
 104                 } else {
 105                         base = stolen[1].start;
 106                         dev_priv->gtt.stolen_size = stolen[1].end - stolen[1].start;
 107                 }
 108
 109                 if (stolen[0].start != stolen[1].start ||
 110                     stolen[0].end != stolen[1].end) {
 111                         DRM_DEBUG_KMS("GTT within stolen memory at 0x%llx-0x%llx\n",
 112                                       (unsigned long long) gtt_start,
 113                                       (unsigned long long) gtt_end - 1);
 114                         DRM_DEBUG_KMS("Stolen memory adjusted to 0x%x-0x%x\n",
 115                                       base, base + (u32) dev_priv->gtt.stolen_size - 1);
 116                 }
 117         }
 118
 119
 120         /* Verify that nothing else uses this physical address. Stolen
 121          * memory should be reserved by the BIOS and hidden from the
 122          * kernel. So if the region is already marked as busy, something
 123          * is seriously wrong.
 124          */
 125 #if 0
 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 #endif
 147
 148         return base;
 149 }
 150
 151 static int i915_setup_compression(struct drm_device *dev, int size)
 152 {
 153         struct drm_i915_private *dev_priv = dev->dev_private;
 154         struct drm_mm_node *compressed_fb, *compressed_llb = NULL;
 155         int ret;
 156
 157         compressed_fb = kzalloc(sizeof(*compressed_fb), GFP_KERNEL);
 158         if (!compressed_fb)
 159                 goto err_llb;
 160
 161         /* Try to over-allocate to reduce reallocations and fragmentation */
 162         ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_fb,
 163                                  size <<= 1, 4096, DRM_MM_SEARCH_DEFAULT);
 164         if (ret)
 165                 ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_fb,
 166                                          size >>= 1, 4096,
 167                                          DRM_MM_SEARCH_DEFAULT);
 168         if (ret)
 169                 goto err_llb;
 170
 171         if (HAS_PCH_SPLIT(dev))
 172                 I915_WRITE(ILK_DPFC_CB_BASE, compressed_fb->start);
 173         else if (IS_GM45(dev)) {
 174                 I915_WRITE(DPFC_CB_BASE, compressed_fb->start);
 175         } else {
 176                 compressed_llb = kzalloc(sizeof(*compressed_llb), GFP_KERNEL);
 177                 if (!compressed_llb)
 178                         goto err_fb;
 179
 180                 ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_llb,
 181                                          4096, 4096, DRM_MM_SEARCH_DEFAULT);
 182                 if (ret)
 183                         goto err_fb;
 184
 185                 dev_priv->fbc.compressed_llb = compressed_llb;
 186
 187                 I915_WRITE(FBC_CFB_BASE,
 188                            dev_priv->mm.stolen_base + compressed_fb->start);
 189                 I915_WRITE(FBC_LL_BASE,
 190                            dev_priv->mm.stolen_base + compressed_llb->start);
 191         }
 192
 193         dev_priv->fbc.compressed_fb = compressed_fb;
 194         dev_priv->fbc.size = size;
 195
 196         DRM_DEBUG_KMS("reserved %d bytes of contiguous stolen space for FBC\n",
 197                       size);
 198
 199         return 0;
 200
 201 err_fb:
 202         kfree(compressed_llb);
 203         drm_mm_remove_node(compressed_fb);
 204 err_llb:
 205         kfree(compressed_fb);
 206         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);
 207         return -ENOSPC;
 208 }
 209
 210 int i915_gem_stolen_setup_compression(struct drm_device *dev, int size)
 211 {
 212         struct drm_i915_private *dev_priv = dev->dev_private;
 213
 214         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 215                 return -ENODEV;
 216
 217         if (size < dev_priv->fbc.size)
 218                 return 0;
 219
 220         /* Release any current block */
 221         i915_gem_stolen_cleanup_compression(dev);
 222
 223         return i915_setup_compression(dev, size);
 224 }
 225
 226 void i915_gem_stolen_cleanup_compression(struct drm_device *dev)
 227 {
 228         struct drm_i915_private *dev_priv = dev->dev_private;
 229
 230         if (dev_priv->fbc.size == 0)
 231                 return;
 232
 233         if (dev_priv->fbc.compressed_fb) {
 234                 drm_mm_remove_node(dev_priv->fbc.compressed_fb);
 235                 kfree(dev_priv->fbc.compressed_fb);
 236         }
 237
 238         if (dev_priv->fbc.compressed_llb) {
 239                 drm_mm_remove_node(dev_priv->fbc.compressed_llb);
 240                 kfree(dev_priv->fbc.compressed_llb);
 241         }
 242
 243         dev_priv->fbc.size = 0;
 244 }
 245
 246 void i915_gem_cleanup_stolen(struct drm_device *dev)
 247 {
 248         struct drm_i915_private *dev_priv = dev->dev_private;
 249
 250         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 251                 return;
 252
 253         i915_gem_stolen_cleanup_compression(dev);
 254         drm_mm_takedown(&dev_priv->mm.stolen);
 255 }
 256
 257 int i915_gem_init_stolen(struct drm_device *dev)
 258 {
 259         struct drm_i915_private *dev_priv = dev->dev_private;
 260         int bios_reserved = 0;
 261
 262 #ifdef CONFIG_INTEL_IOMMU
 263         if (intel_iommu_gfx_mapped && INTEL_INFO(dev)->gen < 8) {
 264                 DRM_INFO("DMAR active, disabling use of stolen memory\n");
 265                 return 0;
 266         }
 267 #endif
 268
 269         if (dev_priv->gtt.stolen_size == 0)
 270                 return 0;
 271
 272         dev_priv->mm.stolen_base = i915_stolen_to_physical(dev);
 273         if (dev_priv->mm.stolen_base == 0)
 274                 return 0;
 275
 276         DRM_DEBUG_KMS("found %zd bytes of stolen memory at %08lx\n",
 277                       dev_priv->gtt.stolen_size, dev_priv->mm.stolen_base);
 278
 279         if (IS_VALLEYVIEW(dev))
 280                 bios_reserved = 1024*1024; /* top 1M on VLV/BYT */
 281
 282         if (WARN_ON(bios_reserved > dev_priv->gtt.stolen_size))
 283                 return 0;
 284
 285         /* Basic memrange allocator for stolen space */
 286         drm_mm_init(&dev_priv->mm.stolen, 0, dev_priv->gtt.stolen_size -
 287                     bios_reserved);
 288
 289         return 0;
 290 }
 291
 292 #if 0
 293 static struct sg_table *
 294 i915_pages_create_for_stolen(struct drm_device *dev,
 295                              u32 offset, u32 size)
 296 {
 297         struct drm_i915_private *dev_priv = dev->dev_private;
 298         struct sg_table *st;
 299         struct scatterlist *sg;
 300
 301         DRM_DEBUG_DRIVER("offset=0x%x, size=%d\n", offset, size);
 302         BUG_ON(offset > dev_priv->gtt.stolen_size - size);
 303
 304         /* We hide that we have no struct page backing our stolen object
 305          * by wrapping the contiguous physical allocation with a fake
 306          * dma mapping in a single scatterlist.
 307          */
 308
 309         st = kmalloc(sizeof(*st), GFP_KERNEL);
 310         if (st == NULL)
 311                 return NULL;
 312
 313         if (sg_alloc_table(st, 1, GFP_KERNEL)) {
 314                 kfree(st);
 315                 return NULL;
 316         }
 317
 318         sg = st->sgl;
 319         sg->offset = 0;
 320         sg->length = size;
 321
 322         sg_dma_address(sg) = (dma_addr_t)dev_priv->mm.stolen_base + offset;
 323         sg_dma_len(sg) = size;
 324
 325         return st;
 326 }
 327 #endif
 328
 329 static int i915_gem_object_get_pages_stolen(struct drm_i915_gem_object *obj)
 330 {
 331         BUG();
 332         return -EINVAL;
 333 }
 334
 335 static void i915_gem_object_put_pages_stolen(struct drm_i915_gem_object *obj)
 336 {
 337 #if 0
 338         /* Should only be called during free */
 339         sg_free_table(obj->pages);
 340         kfree(obj->pages);
 341 #else
 342         BUG();
 343 #endif
 344 }
 345
 346 static const struct drm_i915_gem_object_ops i915_gem_object_stolen_ops = {
 347         .get_pages = i915_gem_object_get_pages_stolen,
 348         .put_pages = i915_gem_object_put_pages_stolen,
 349 };
 350
 351 static struct drm_i915_gem_object *
 352 _i915_gem_object_create_stolen(struct drm_device *dev,
 353                                struct drm_mm_node *stolen)
 354 {
 355         struct drm_i915_gem_object *obj;
 356
 357 #if 0
 358         obj = i915_gem_object_alloc(dev);
 359 #else
 360         obj = NULL;
 361 #endif
 362         if (obj == NULL)
 363                 return NULL;
 364
 365         drm_gem_private_object_init(dev, &obj->base, stolen->size);
 366         i915_gem_object_init(obj, &i915_gem_object_stolen_ops);
 367
 368 #if 0
 369         obj->pages = i915_pages_create_for_stolen(dev,
 370                                                   stolen->start, stolen->size);
 371 #else
 372         obj->pages = NULL;
 373 #endif
 374         if (obj->pages == NULL)
 375                 goto cleanup;
 376
 377         obj->has_dma_mapping = true;
 378         i915_gem_object_pin_pages(obj);
 379         obj->stolen = stolen;
 380
 381         obj->base.read_domains = I915_GEM_DOMAIN_CPU | I915_GEM_DOMAIN_GTT;
 382         obj->cache_level = HAS_LLC(dev) ? I915_CACHE_LLC : I915_CACHE_NONE;
 383
 384         return obj;
 385
 386 cleanup:
 387         i915_gem_object_free(obj);
 388         return NULL;
 389 }
 390
 391 struct drm_i915_gem_object *
 392 i915_gem_object_create_stolen(struct drm_device *dev, u32 size)
 393 {
 394         struct drm_i915_private *dev_priv = dev->dev_private;
 395         struct drm_i915_gem_object *obj;
 396         struct drm_mm_node *stolen;
 397         int ret;
 398
 399         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 400                 return NULL;
 401
 402         DRM_DEBUG_KMS("creating stolen object: size=%x\n", size);
 403         if (size == 0)
 404                 return NULL;
 405
 406         stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
 407         if (!stolen)
 408                 return NULL;
 409
 410         ret = drm_mm_insert_node(&dev_priv->mm.stolen, stolen, size,
 411                                  4096, DRM_MM_SEARCH_DEFAULT);
 412         if (ret) {
 413                 kfree(stolen);
 414                 return NULL;
 415         }
 416
 417         obj = _i915_gem_object_create_stolen(dev, stolen);
 418         if (obj)
 419                 return obj;
 420
 421         drm_mm_remove_node(stolen);
 422         kfree(stolen);
 423         return NULL;
 424 }
 425
 426 struct drm_i915_gem_object *
 427 i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
 428                                                u32 stolen_offset,
 429                                                u32 gtt_offset,
 430                                                u32 size)
 431 {
 432         struct drm_i915_private *dev_priv = dev->dev_private;
 433         struct i915_address_space *ggtt = &dev_priv->gtt.base;
 434         struct drm_i915_gem_object *obj;
 435         struct drm_mm_node *stolen;
 436         struct i915_vma *vma;
 437         int ret;
 438
 439         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 440                 return NULL;
 441
 442         DRM_DEBUG_KMS("creating preallocated stolen object: stolen_offset=%x, gtt_offset=%x, size=%x\n",
 443                         stolen_offset, gtt_offset, size);
 444
 445         /* KISS and expect everything to be page-aligned */
 446         BUG_ON(stolen_offset & 4095);
 447         BUG_ON(size & 4095);
 448
 449         if (WARN_ON(size == 0))
 450                 return NULL;
 451
 452         stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
 453         if (!stolen)
 454                 return NULL;
 455
 456         stolen->start = stolen_offset;
 457         stolen->size = size;
 458         ret = drm_mm_reserve_node(&dev_priv->mm.stolen, stolen);
 459         if (ret) {
 460                 DRM_DEBUG_KMS("failed to allocate stolen space\n");
 461                 kfree(stolen);
 462                 return NULL;
 463         }
 464
 465         obj = _i915_gem_object_create_stolen(dev, stolen);
 466         if (obj == NULL) {
 467                 DRM_DEBUG_KMS("failed to allocate stolen object\n");
 468                 drm_mm_remove_node(stolen);
 469                 kfree(stolen);
 470                 return NULL;
 471         }
 472
 473         /* Some objects just need physical mem from stolen space */
 474         if (gtt_offset == I915_GTT_OFFSET_NONE)
 475                 return obj;
 476
 477         vma = i915_gem_obj_lookup_or_create_vma(obj, ggtt);
 478         if (IS_ERR(vma)) {
 479                 ret = PTR_ERR(vma);
 480                 goto err_out;
 481         }
 482
 483         /* To simplify the initialisation sequence between KMS and GTT,
 484          * we allow construction of the stolen object prior to
 485          * setting up the GTT space. The actual reservation will occur
 486          * later.
 487          */
 488         vma->node.start = gtt_offset;
 489         vma->node.size = size;
 490         if (drm_mm_initialized(&ggtt->mm)) {
 491                 ret = drm_mm_reserve_node(&ggtt->mm, &vma->node);
 492                 if (ret) {
 493                         DRM_DEBUG_KMS("failed to allocate stolen GTT space\n");
 494                         goto err_vma;
 495                 }
 496         }
 497
 498         obj->has_global_gtt_mapping = 1;
 499
 500         list_add_tail(&obj->global_list, &dev_priv->mm.bound_list);
 501         list_add_tail(&vma->mm_list, &ggtt->inactive_list);
 502         i915_gem_object_pin_pages(obj);
 503
 504         return obj;
 505
 506 err_vma:
 507         i915_gem_vma_destroy(vma);
 508 err_out:
 509         drm_mm_remove_node(stolen);
 510         kfree(stolen);
 511         drm_gem_object_unreference(&obj->base);
 512         return NULL;
 513 }
 514
 515 void
 516 i915_gem_object_release_stolen(struct drm_i915_gem_object *obj)
 517 {
 518         if (obj->stolen) {
 519                 drm_mm_remove_node(obj->stolen);
 520                 kfree(obj->stolen);
 521                 obj->stolen = NULL;
 522         }
 523 }