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         /* Verify that nothing else uses this physical address. Stolen
  78          * memory should be reserved by the BIOS and hidden from the
  79          * kernel. So if the region is already marked as busy, something
  80          * is seriously wrong.
  81          */
  82         r = devm_request_mem_region(dev->dev, base, dev_priv->gtt.stolen_size,
  83                                     "Graphics Stolen Memory");
  84         if (r == NULL) {
  85                 /*
  86                  * One more attempt but this time requesting region from
  87                  * base + 1, as we have seen that this resolves the region
  88                  * conflict with the PCI Bus.
  89                  * This is a BIOS w/a: Some BIOS wrap stolen in the root
  90                  * PCI bus, but have an off-by-one error. Hence retry the
  91                  * reservation starting from 1 instead of 0.
  92                  */
  93                 r = devm_request_mem_region(dev->dev, base + 1,
  94                                             dev_priv->gtt.stolen_size - 1,
  95                                             "Graphics Stolen Memory");
  96                 if (r == NULL) {
  97                         DRM_ERROR("conflict detected with stolen region: [0x%08x - 0x%08x]\n",
  98                                   base, base + (uint32_t)dev_priv->gtt.stolen_size);
  99                         base = 0;
 100                 }
 101         }
 102
 103         return base;
 104 }
 105
 106 static int i915_setup_compression(struct drm_device *dev, int size)
 107 {
 108         struct drm_i915_private *dev_priv = dev->dev_private;
 109         struct drm_mm_node *compressed_fb, *uninitialized_var(compressed_llb);
 110         int ret;
 111
 112         compressed_fb = kzalloc(sizeof(*compressed_fb), GFP_KERNEL);
 113         if (!compressed_fb)
 114                 goto err_llb;
 115
 116         /* Try to over-allocate to reduce reallocations and fragmentation */
 117         ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_fb,
 118                                  size <<= 1, 4096, DRM_MM_SEARCH_DEFAULT);
 119         if (ret)
 120                 ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_fb,
 121                                          size >>= 1, 4096,
 122                                          DRM_MM_SEARCH_DEFAULT);
 123         if (ret)
 124                 goto err_llb;
 125
 126         if (HAS_PCH_SPLIT(dev))
 127                 I915_WRITE(ILK_DPFC_CB_BASE, compressed_fb->start);
 128         else if (IS_GM45(dev)) {
 129                 I915_WRITE(DPFC_CB_BASE, compressed_fb->start);
 130         } else {
 131                 compressed_llb = kzalloc(sizeof(*compressed_llb), GFP_KERNEL);
 132                 if (!compressed_llb)
 133                         goto err_fb;
 134
 135                 ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_llb,
 136                                          4096, 4096, DRM_MM_SEARCH_DEFAULT);
 137                 if (ret)
 138                         goto err_fb;
 139
 140                 dev_priv->fbc.compressed_llb = compressed_llb;
 141
 142                 I915_WRITE(FBC_CFB_BASE,
 143                            dev_priv->mm.stolen_base + compressed_fb->start);
 144                 I915_WRITE(FBC_LL_BASE,
 145                            dev_priv->mm.stolen_base + compressed_llb->start);
 146         }
 147
 148         dev_priv->fbc.compressed_fb = compressed_fb;
 149         dev_priv->fbc.size = size;
 150
 151         DRM_DEBUG_KMS("reserved %d bytes of contiguous stolen space for FBC\n",
 152                       size);
 153
 154         return 0;
 155
 156 err_fb:
 157         kfree(compressed_llb);
 158         drm_mm_remove_node(compressed_fb);
 159 err_llb:
 160         kfree(compressed_fb);
 161         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);
 162         return -ENOSPC;
 163 }
 164
 165 int i915_gem_stolen_setup_compression(struct drm_device *dev, int size)
 166 {
 167         struct drm_i915_private *dev_priv = dev->dev_private;
 168
 169         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 170                 return -ENODEV;
 171
 172         if (size < dev_priv->fbc.size)
 173                 return 0;
 174
 175         /* Release any current block */
 176         i915_gem_stolen_cleanup_compression(dev);
 177
 178         return i915_setup_compression(dev, size);
 179 }
 180
 181 void i915_gem_stolen_cleanup_compression(struct drm_device *dev)
 182 {
 183         struct drm_i915_private *dev_priv = dev->dev_private;
 184
 185         if (dev_priv->fbc.size == 0)
 186                 return;
 187
 188         if (dev_priv->fbc.compressed_fb) {
 189                 drm_mm_remove_node(dev_priv->fbc.compressed_fb);
 190                 kfree(dev_priv->fbc.compressed_fb);
 191         }
 192
 193         if (dev_priv->fbc.compressed_llb) {
 194                 drm_mm_remove_node(dev_priv->fbc.compressed_llb);
 195                 kfree(dev_priv->fbc.compressed_llb);
 196         }
 197
 198         dev_priv->fbc.size = 0;
 199 }
 200
 201 void i915_gem_cleanup_stolen(struct drm_device *dev)
 202 {
 203         struct drm_i915_private *dev_priv = dev->dev_private;
 204
 205         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 206                 return;
 207
 208         i915_gem_stolen_cleanup_compression(dev);
 209         drm_mm_takedown(&dev_priv->mm.stolen);
 210 }
 211
 212 int i915_gem_init_stolen(struct drm_device *dev)
 213 {
 214         struct drm_i915_private *dev_priv = dev->dev_private;
 215         int bios_reserved = 0;
 216
 217 #ifdef CONFIG_INTEL_IOMMU
 218         if (intel_iommu_gfx_mapped && INTEL_INFO(dev)->gen < 8) {
 219                 DRM_INFO("DMAR active, disabling use of stolen memory\n");
 220                 return 0;
 221         }
 222 #endif
 223
 224         if (dev_priv->gtt.stolen_size == 0)
 225                 return 0;
 226
 227         dev_priv->mm.stolen_base = i915_stolen_to_physical(dev);
 228         if (dev_priv->mm.stolen_base == 0)
 229                 return 0;
 230
 231         DRM_DEBUG_KMS("found %zd bytes of stolen memory at %08lx\n",
 232                       dev_priv->gtt.stolen_size, dev_priv->mm.stolen_base);
 233
 234         if (IS_VALLEYVIEW(dev))
 235                 bios_reserved = 1024*1024; /* top 1M on VLV/BYT */
 236
 237         if (WARN_ON(bios_reserved > dev_priv->gtt.stolen_size))
 238                 return 0;
 239
 240         /* Basic memrange allocator for stolen space */
 241         drm_mm_init(&dev_priv->mm.stolen, 0, dev_priv->gtt.stolen_size -
 242                     bios_reserved);
 243
 244         return 0;
 245 }
 246
 247 static struct sg_table *
 248 i915_pages_create_for_stolen(struct drm_device *dev,
 249                              u32 offset, u32 size)
 250 {
 251         struct drm_i915_private *dev_priv = dev->dev_private;
 252         struct sg_table *st;
 253         struct scatterlist *sg;
 254
 255         DRM_DEBUG_DRIVER("offset=0x%x, size=%d\n", offset, size);
 256         BUG_ON(offset > dev_priv->gtt.stolen_size - size);
 257
 258         /* We hide that we have no struct page backing our stolen object
 259          * by wrapping the contiguous physical allocation with a fake
 260          * dma mapping in a single scatterlist.
 261          */
 262
 263         st = kmalloc(sizeof(*st), GFP_KERNEL);
 264         if (st == NULL)
 265                 return NULL;
 266
 267         if (sg_alloc_table(st, 1, GFP_KERNEL)) {
 268                 kfree(st);
 269                 return NULL;
 270         }
 271
 272         sg = st->sgl;
 273         sg->offset = 0;
 274         sg->length = size;
 275
 276         sg_dma_address(sg) = (dma_addr_t)dev_priv->mm.stolen_base + offset;
 277         sg_dma_len(sg) = size;
 278
 279         return st;
 280 }
 281
 282 static int i915_gem_object_get_pages_stolen(struct drm_i915_gem_object *obj)
 283 {
 284         BUG();
 285         return -EINVAL;
 286 }
 287
 288 static void i915_gem_object_put_pages_stolen(struct drm_i915_gem_object *obj)
 289 {
 290         /* Should only be called during free */
 291         sg_free_table(obj->pages);
 292         kfree(obj->pages);
 293 }
 294
 295
 296 static void
 297 i915_gem_object_release_stolen(struct drm_i915_gem_object *obj)
 298 {
 299         if (obj->stolen) {
 300                 drm_mm_remove_node(obj->stolen);
 301                 kfree(obj->stolen);
 302                 obj->stolen = NULL;
 303         }
 304 }
 305 static const struct drm_i915_gem_object_ops i915_gem_object_stolen_ops = {
 306         .get_pages = i915_gem_object_get_pages_stolen,
 307         .put_pages = i915_gem_object_put_pages_stolen,
 308         .release = i915_gem_object_release_stolen,
 309 };
 310
 311 static struct drm_i915_gem_object *
 312 _i915_gem_object_create_stolen(struct drm_device *dev,
 313                                struct drm_mm_node *stolen)
 314 {
 315         struct drm_i915_gem_object *obj;
 316
 317         obj = i915_gem_object_alloc(dev);
 318         if (obj == NULL)
 319                 return NULL;
 320
 321         drm_gem_private_object_init(dev, &obj->base, stolen->size);
 322         i915_gem_object_init(obj, &i915_gem_object_stolen_ops);
 323
 324         obj->pages = i915_pages_create_for_stolen(dev,
 325                                                   stolen->start, stolen->size);
 326         if (obj->pages == NULL)
 327                 goto cleanup;
 328
 329         obj->has_dma_mapping = true;
 330         i915_gem_object_pin_pages(obj);
 331         obj->stolen = stolen;
 332
 333         obj->base.read_domains = I915_GEM_DOMAIN_CPU | I915_GEM_DOMAIN_GTT;
 334         obj->cache_level = HAS_LLC(dev) ? I915_CACHE_LLC : I915_CACHE_NONE;
 335
 336         return obj;
 337
 338 cleanup:
 339         i915_gem_object_free(obj);
 340         return NULL;
 341 }
 342
 343 struct drm_i915_gem_object *
 344 i915_gem_object_create_stolen(struct drm_device *dev, u32 size)
 345 {
 346         struct drm_i915_private *dev_priv = dev->dev_private;
 347         struct drm_i915_gem_object *obj;
 348         struct drm_mm_node *stolen;
 349         int ret;
 350
 351         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 352                 return NULL;
 353
 354         DRM_DEBUG_KMS("creating stolen object: size=%x\n", size);
 355         if (size == 0)
 356                 return NULL;
 357
 358         stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
 359         if (!stolen)
 360                 return NULL;
 361
 362         ret = drm_mm_insert_node(&dev_priv->mm.stolen, stolen, size,
 363                                  4096, DRM_MM_SEARCH_DEFAULT);
 364         if (ret) {
 365                 kfree(stolen);
 366                 return NULL;
 367         }
 368
 369         obj = _i915_gem_object_create_stolen(dev, stolen);
 370         if (obj)
 371                 return obj;
 372
 373         drm_mm_remove_node(stolen);
 374         kfree(stolen);
 375         return NULL;
 376 }
 377
 378 struct drm_i915_gem_object *
 379 i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
 380                                                u32 stolen_offset,
 381                                                u32 gtt_offset,
 382                                                u32 size)
 383 {
 384         struct drm_i915_private *dev_priv = dev->dev_private;
 385         struct i915_address_space *ggtt = &dev_priv->gtt.base;
 386         struct drm_i915_gem_object *obj;
 387         struct drm_mm_node *stolen;
 388         struct i915_vma *vma;
 389         int ret;
 390
 391         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 392                 return NULL;
 393
 394         DRM_DEBUG_KMS("creating preallocated stolen object: stolen_offset=%x, gtt_offset=%x, size=%x\n",
 395                         stolen_offset, gtt_offset, size);
 396
 397         /* KISS and expect everything to be page-aligned */
 398         BUG_ON(stolen_offset & 4095);
 399         BUG_ON(size & 4095);
 400
 401         if (WARN_ON(size == 0))
 402                 return NULL;
 403
 404         stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
 405         if (!stolen)
 406                 return NULL;
 407
 408         stolen->start = stolen_offset;
 409         stolen->size = size;
 410         ret = drm_mm_reserve_node(&dev_priv->mm.stolen, stolen);
 411         if (ret) {
 412                 DRM_DEBUG_KMS("failed to allocate stolen space\n");
 413                 kfree(stolen);
 414                 return NULL;
 415         }
 416
 417         obj = _i915_gem_object_create_stolen(dev, stolen);
 418         if (obj == NULL) {
 419                 DRM_DEBUG_KMS("failed to allocate stolen object\n");
 420                 drm_mm_remove_node(stolen);
 421                 kfree(stolen);
 422                 return NULL;
 423         }
 424
 425         /* Some objects just need physical mem from stolen space */
 426         if (gtt_offset == I915_GTT_OFFSET_NONE)
 427                 return obj;
 428
 429         vma = i915_gem_obj_lookup_or_create_vma(obj, ggtt);
 430         if (IS_ERR(vma)) {
 431                 ret = PTR_ERR(vma);
 432                 goto err_out;
 433         }
 434
 435         /* To simplify the initialisation sequence between KMS and GTT,
 436          * we allow construction of the stolen object prior to
 437          * setting up the GTT space. The actual reservation will occur
 438          * later.
 439          */
 440         vma->node.start = gtt_offset;
 441         vma->node.size = size;
 442         if (drm_mm_initialized(&ggtt->mm)) {
 443                 ret = drm_mm_reserve_node(&ggtt->mm, &vma->node);
 444                 if (ret) {
 445                         DRM_DEBUG_KMS("failed to allocate stolen GTT space\n");
 446                         goto err_vma;
 447                 }
 448         }
 449
 450         obj->has_global_gtt_mapping = 1;
 451
 452         list_add_tail(&obj->global_list, &dev_priv->mm.bound_list);
 453         list_add_tail(&vma->mm_list, &ggtt->inactive_list);
 454         i915_gem_object_pin_pages(obj);
 455
 456         return obj;
 457
 458 err_vma:
 459         i915_gem_vma_destroy(vma);
 460 err_out:
 461         drm_mm_remove_node(stolen);
 462         kfree(stolen);
 463         drm_gem_object_unreference(&obj->base);
 464         return NULL;
 465 }