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 pci_dev *pdev = dev_priv->bridge_dev;
  49         struct resource *r;
  50         u32 base;
  51
  52         /* On the machines I have tested the Graphics Base of Stolen Memory
  53          * is unreliable, so on those compute the base by subtracting the
  54          * stolen memory from the Top of Low Usable DRAM which is where the
  55          * BIOS places the graphics stolen memory.
  56          *
  57          * On gen2, the layout is slightly different with the Graphics Segment
  58          * immediately following Top of Memory (or Top of Usable DRAM). Note
  59          * it appears that TOUD is only reported by 865g, so we just use the
  60          * top of memory as determined by the e820 probe.
  61          *
  62          * XXX gen2 requires an unavailable symbol and 945gm fails with
  63          * its value of TOLUD.
  64          */
  65         base = 0;
  66         if (IS_VALLEYVIEW(dev)) {
  67                 pci_read_config_dword(dev->pdev, 0x5c, &base);
  68                 base &= ~((1<<20) - 1);
  69         } else if (INTEL_INFO(dev)->gen >= 6) {
  70                 /* Read Base Data of Stolen Memory Register (BDSM) directly.
  71                  * Note that there is also a MCHBAR miror at 0x1080c0 or
  72                  * we could use device 2:0x5c instead.
  73                 */
  74                 pci_read_config_dword(pdev, 0xB0, &base);
  75                 base &= ~4095; /* lower bits used for locking register */
  76         } else if (INTEL_INFO(dev)->gen > 3 || IS_G33(dev)) {
  77                 /* Read Graphics Base of Stolen Memory directly */
  78                 pci_read_config_dword(pdev, 0xA4, &base);
  79 #if 0
  80         } else if (IS_GEN3(dev)) {
  81                 u8 val;
  82                 /* Stolen is immediately below Top of Low Usable DRAM */
  83                 pci_read_config_byte(pdev, 0x9c, &val);
  84                 base = val >> 3 << 27;
  85                 base -= dev_priv->mm.gtt->stolen_size;
  86         } else {
  87                 /* Stolen is immediately above Top of Memory */
  88                 base = max_low_pfn_mapped << PAGE_SHIFT;
  89 #endif
  90         }
  91
  92         if (base == 0)
  93                 return 0;
  94
  95         /* Verify that nothing else uses this physical address. Stolen
  96          * memory should be reserved by the BIOS and hidden from the
  97          * kernel. So if the region is already marked as busy, something
  98          * is seriously wrong.
  99          */
 100         r = devm_request_mem_region(dev->dev, base, dev_priv->gtt.stolen_size,
 101                                     "Graphics Stolen Memory");
 102         if (r == NULL) {
 103                 DRM_ERROR("conflict detected with stolen region: [0x%08x - 0x%08x]\n",
 104                           base, base + (uint32_t)dev_priv->gtt.stolen_size);
 105                 base = 0;
 106         }
 107
 108         return base;
 109 }
 110
 111 static int i915_setup_compression(struct drm_device *dev, int size)
 112 {
 113         struct drm_i915_private *dev_priv = dev->dev_private;
 114         struct drm_mm_node *compressed_fb, *uninitialized_var(compressed_llb);
 115         int ret;
 116
 117         compressed_fb = kzalloc(sizeof(*compressed_fb), GFP_KERNEL);
 118         if (!compressed_fb)
 119                 goto err_llb;
 120
 121         /* Try to over-allocate to reduce reallocations and fragmentation */
 122         ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_fb,
 123                                  size <<= 1, 4096, DRM_MM_SEARCH_DEFAULT);
 124         if (ret)
 125                 ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_fb,
 126                                          size >>= 1, 4096,
 127                                          DRM_MM_SEARCH_DEFAULT);
 128         if (ret)
 129                 goto err_llb;
 130
 131         if (HAS_PCH_SPLIT(dev))
 132                 I915_WRITE(ILK_DPFC_CB_BASE, compressed_fb->start);
 133         else if (IS_GM45(dev)) {
 134                 I915_WRITE(DPFC_CB_BASE, compressed_fb->start);
 135         } else {
 136                 compressed_llb = kzalloc(sizeof(*compressed_llb), GFP_KERNEL);
 137                 if (!compressed_llb)
 138                         goto err_fb;
 139
 140                 ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_llb,
 141                                          4096, 4096, DRM_MM_SEARCH_DEFAULT);
 142                 if (ret)
 143                         goto err_fb;
 144
 145                 dev_priv->fbc.compressed_llb = compressed_llb;
 146
 147                 I915_WRITE(FBC_CFB_BASE,
 148                            dev_priv->mm.stolen_base + compressed_fb->start);
 149                 I915_WRITE(FBC_LL_BASE,
 150                            dev_priv->mm.stolen_base + compressed_llb->start);
 151         }
 152
 153         dev_priv->fbc.compressed_fb = compressed_fb;
 154         dev_priv->fbc.size = size;
 155
 156         DRM_DEBUG_KMS("reserved %d bytes of contiguous stolen space for FBC\n",
 157                       size);
 158
 159         return 0;
 160
 161 err_fb:
 162         kfree(compressed_llb);
 163         drm_mm_remove_node(compressed_fb);
 164 err_llb:
 165         kfree(compressed_fb);
 166         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);
 167         return -ENOSPC;
 168 }
 169
 170 int i915_gem_stolen_setup_compression(struct drm_device *dev, int size)
 171 {
 172         struct drm_i915_private *dev_priv = dev->dev_private;
 173
 174         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 175                 return -ENODEV;
 176
 177         if (size < dev_priv->fbc.size)
 178                 return 0;
 179
 180         /* Release any current block */
 181         i915_gem_stolen_cleanup_compression(dev);
 182
 183         return i915_setup_compression(dev, size);
 184 }
 185
 186 void i915_gem_stolen_cleanup_compression(struct drm_device *dev)
 187 {
 188         struct drm_i915_private *dev_priv = dev->dev_private;
 189
 190         if (dev_priv->fbc.size == 0)
 191                 return;
 192
 193         if (dev_priv->fbc.compressed_fb) {
 194                 drm_mm_remove_node(dev_priv->fbc.compressed_fb);
 195                 kfree(dev_priv->fbc.compressed_fb);
 196         }
 197
 198         if (dev_priv->fbc.compressed_llb) {
 199                 drm_mm_remove_node(dev_priv->fbc.compressed_llb);
 200                 kfree(dev_priv->fbc.compressed_llb);
 201         }
 202
 203         dev_priv->fbc.size = 0;
 204 }
 205
 206 void i915_gem_cleanup_stolen(struct drm_device *dev)
 207 {
 208         struct drm_i915_private *dev_priv = dev->dev_private;
 209
 210         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 211                 return;
 212
 213         i915_gem_stolen_cleanup_compression(dev);
 214         drm_mm_takedown(&dev_priv->mm.stolen);
 215 }
 216
 217 int i915_gem_init_stolen(struct drm_device *dev)
 218 {
 219         struct drm_i915_private *dev_priv = dev->dev_private;
 220         int bios_reserved = 0;
 221
 222         dev_priv->mm.stolen_base = i915_stolen_to_physical(dev);
 223         if (dev_priv->mm.stolen_base == 0)
 224                 return 0;
 225
 226         DRM_DEBUG_KMS("found %zd bytes of stolen memory at %08lx\n",
 227                       dev_priv->gtt.stolen_size, dev_priv->mm.stolen_base);
 228
 229         if (IS_VALLEYVIEW(dev))
 230                 bios_reserved = 1024*1024; /* top 1M on VLV/BYT */
 231
 232         if (WARN_ON(bios_reserved > dev_priv->gtt.stolen_size))
 233                 return 0;
 234
 235         /* Basic memrange allocator for stolen space */
 236         drm_mm_init(&dev_priv->mm.stolen, 0, dev_priv->gtt.stolen_size -
 237                     bios_reserved);
 238
 239         return 0;
 240 }
 241
 242 static struct sg_table *
 243 i915_pages_create_for_stolen(struct drm_device *dev,
 244                              u32 offset, u32 size)
 245 {
 246         struct drm_i915_private *dev_priv = dev->dev_private;
 247         struct sg_table *st;
 248         struct scatterlist *sg;
 249
 250         DRM_DEBUG_DRIVER("offset=0x%x, size=%d\n", offset, size);
 251         BUG_ON(offset > dev_priv->gtt.stolen_size - size);
 252
 253         /* We hide that we have no struct page backing our stolen object
 254          * by wrapping the contiguous physical allocation with a fake
 255          * dma mapping in a single scatterlist.
 256          */
 257
 258         st = kmalloc(sizeof(*st), GFP_KERNEL);
 259         if (st == NULL)
 260                 return NULL;
 261
 262         if (sg_alloc_table(st, 1, GFP_KERNEL)) {
 263                 kfree(st);
 264                 return NULL;
 265         }
 266
 267         sg = st->sgl;
 268         sg->offset = offset;
 269         sg->length = size;
 270
 271         sg_dma_address(sg) = (dma_addr_t)dev_priv->mm.stolen_base + offset;
 272         sg_dma_len(sg) = size;
 273
 274         return st;
 275 }
 276
 277 static int i915_gem_object_get_pages_stolen(struct drm_i915_gem_object *obj)
 278 {
 279         BUG();
 280         return -EINVAL;
 281 }
 282
 283 static void i915_gem_object_put_pages_stolen(struct drm_i915_gem_object *obj)
 284 {
 285         /* Should only be called during free */
 286         sg_free_table(obj->pages);
 287         kfree(obj->pages);
 288 }
 289
 290 static const struct drm_i915_gem_object_ops i915_gem_object_stolen_ops = {
 291         .get_pages = i915_gem_object_get_pages_stolen,
 292         .put_pages = i915_gem_object_put_pages_stolen,
 293 };
 294
 295 static struct drm_i915_gem_object *
 296 _i915_gem_object_create_stolen(struct drm_device *dev,
 297                                struct drm_mm_node *stolen)
 298 {
 299         struct drm_i915_gem_object *obj;
 300
 301         obj = i915_gem_object_alloc(dev);
 302         if (obj == NULL)
 303                 return NULL;
 304
 305         drm_gem_private_object_init(dev, &obj->base, stolen->size);
 306         i915_gem_object_init(obj, &i915_gem_object_stolen_ops);
 307
 308         obj->pages = i915_pages_create_for_stolen(dev,
 309                                                   stolen->start, stolen->size);
 310         if (obj->pages == NULL)
 311                 goto cleanup;
 312
 313         obj->has_dma_mapping = true;
 314         i915_gem_object_pin_pages(obj);
 315         obj->stolen = stolen;
 316
 317         obj->base.write_domain = I915_GEM_DOMAIN_GTT;
 318         obj->base.read_domains = I915_GEM_DOMAIN_GTT;
 319         obj->cache_level = I915_CACHE_NONE;
 320
 321         return obj;
 322
 323 cleanup:
 324         i915_gem_object_free(obj);
 325         return NULL;
 326 }
 327
 328 struct drm_i915_gem_object *
 329 i915_gem_object_create_stolen(struct drm_device *dev, u32 size)
 330 {
 331         struct drm_i915_private *dev_priv = dev->dev_private;
 332         struct drm_i915_gem_object *obj;
 333         struct drm_mm_node *stolen;
 334         int ret;
 335
 336         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 337                 return NULL;
 338
 339         DRM_DEBUG_KMS("creating stolen object: size=%x\n", size);
 340         if (size == 0)
 341                 return NULL;
 342
 343         stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
 344         if (!stolen)
 345                 return NULL;
 346
 347         ret = drm_mm_insert_node(&dev_priv->mm.stolen, stolen, size,
 348                                  4096, DRM_MM_SEARCH_DEFAULT);
 349         if (ret) {
 350                 kfree(stolen);
 351                 return NULL;
 352         }
 353
 354         obj = _i915_gem_object_create_stolen(dev, stolen);
 355         if (obj)
 356                 return obj;
 357
 358         drm_mm_remove_node(stolen);
 359         kfree(stolen);
 360         return NULL;
 361 }
 362
 363 struct drm_i915_gem_object *
 364 i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
 365                                                u32 stolen_offset,
 366                                                u32 gtt_offset,
 367                                                u32 size)
 368 {
 369         struct drm_i915_private *dev_priv = dev->dev_private;
 370         struct drm_i915_gem_object *obj;
 371         struct drm_mm_node *stolen;
 372         int ret;
 373
 374         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 375                 return NULL;
 376
 377         DRM_DEBUG_KMS("creating preallocated stolen object: stolen_offset=%x, gtt_offset=%x, size=%x\n",
 378                         stolen_offset, gtt_offset, size);
 379
 380         /* KISS and expect everything to be page-aligned */
 381         BUG_ON(stolen_offset & 4095);
 382         BUG_ON(size & 4095);
 383
 384         if (WARN_ON(size == 0))
 385                 return NULL;
 386
 387         stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
 388         if (!stolen)
 389                 return NULL;
 390
 391         stolen->start = stolen_offset;
 392         stolen->size = size;
 393         ret = drm_mm_reserve_node(&dev_priv->mm.stolen, stolen);
 394         if (ret) {
 395                 DRM_DEBUG_KMS("failed to allocate stolen space\n");
 396                 kfree(stolen);
 397                 return NULL;
 398         }
 399
 400         obj = _i915_gem_object_create_stolen(dev, stolen);
 401         if (obj == NULL) {
 402                 DRM_DEBUG_KMS("failed to allocate stolen object\n");
 403                 drm_mm_remove_node(stolen);
 404                 kfree(stolen);
 405                 return NULL;
 406         }
 407
 408         /* Some objects just need physical mem from stolen space */
 409         if (gtt_offset == I915_GTT_OFFSET_NONE)
 410                 return obj;
 411
 412         /* To simplify the initialisation sequence between KMS and GTT,
 413          * we allow construction of the stolen object prior to
 414          * setting up the GTT space. The actual reservation will occur
 415          * later.
 416          */
 417         obj->gtt_space.start = gtt_offset;
 418         obj->gtt_space.size = size;
 419         if (drm_mm_initialized(&dev_priv->mm.gtt_space)) {
 420                 ret = drm_mm_reserve_node(&dev_priv->mm.gtt_space,
 421                                           &obj->gtt_space);
 422                 if (ret) {
 423                         DRM_DEBUG_KMS("failed to allocate stolen GTT space\n");
 424                         goto unref_out;
 425                 }
 426         }
 427
 428         obj->has_global_gtt_mapping = 1;
 429
 430         list_add_tail(&obj->global_list, &dev_priv->mm.bound_list);
 431         list_add_tail(&obj->mm_list, &dev_priv->mm.inactive_list);
 432
 433         return obj;
 434
 435 unref_out:
 436         drm_gem_object_unreference(&obj->base);
 437         return NULL;
 438 }
 439
 440 void
 441 i915_gem_object_release_stolen(struct drm_i915_gem_object *obj)
 442 {
 443         if (obj->stolen) {
 444                 drm_mm_remove_node(obj->stolen);
 445                 kfree(obj->stolen);
 446                 obj->stolen = NULL;
 447         }
 448 }