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                 DRM_ERROR("conflict detected with stolen region: [0x%08x - 0x%08x]\n",
  86                           base, base + (uint32_t)dev_priv->gtt.stolen_size);
  87                 base = 0;
  88         }
  89
  90         return base;
  91 }
  92
  93 static int i915_setup_compression(struct drm_device *dev, int size)
  94 {
  95         struct drm_i915_private *dev_priv = dev->dev_private;
  96         struct drm_mm_node *compressed_fb, *uninitialized_var(compressed_llb);
  97         int ret;
  98
  99         compressed_fb = kzalloc(sizeof(*compressed_fb), GFP_KERNEL);
 100         if (!compressed_fb)
 101                 goto err_llb;
 102
 103         /* Try to over-allocate to reduce reallocations and fragmentation */
 104         ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_fb,
 105                                  size <<= 1, 4096, DRM_MM_SEARCH_DEFAULT);
 106         if (ret)
 107                 ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_fb,
 108                                          size >>= 1, 4096,
 109                                          DRM_MM_SEARCH_DEFAULT);
 110         if (ret)
 111                 goto err_llb;
 112
 113         if (HAS_PCH_SPLIT(dev))
 114                 I915_WRITE(ILK_DPFC_CB_BASE, compressed_fb->start);
 115         else if (IS_GM45(dev)) {
 116                 I915_WRITE(DPFC_CB_BASE, compressed_fb->start);
 117         } else {
 118                 compressed_llb = kzalloc(sizeof(*compressed_llb), GFP_KERNEL);
 119                 if (!compressed_llb)
 120                         goto err_fb;
 121
 122                 ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_llb,
 123                                          4096, 4096, DRM_MM_SEARCH_DEFAULT);
 124                 if (ret)
 125                         goto err_fb;
 126
 127                 dev_priv->fbc.compressed_llb = compressed_llb;
 128
 129                 I915_WRITE(FBC_CFB_BASE,
 130                            dev_priv->mm.stolen_base + compressed_fb->start);
 131                 I915_WRITE(FBC_LL_BASE,
 132                            dev_priv->mm.stolen_base + compressed_llb->start);
 133         }
 134
 135         dev_priv->fbc.compressed_fb = compressed_fb;
 136         dev_priv->fbc.size = size;
 137
 138         DRM_DEBUG_KMS("reserved %d bytes of contiguous stolen space for FBC\n",
 139                       size);
 140
 141         return 0;
 142
 143 err_fb:
 144         kfree(compressed_llb);
 145         drm_mm_remove_node(compressed_fb);
 146 err_llb:
 147         kfree(compressed_fb);
 148         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);
 149         return -ENOSPC;
 150 }
 151
 152 int i915_gem_stolen_setup_compression(struct drm_device *dev, int size)
 153 {
 154         struct drm_i915_private *dev_priv = dev->dev_private;
 155
 156         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 157                 return -ENODEV;
 158
 159         if (size < dev_priv->fbc.size)
 160                 return 0;
 161
 162         /* Release any current block */
 163         i915_gem_stolen_cleanup_compression(dev);
 164
 165         return i915_setup_compression(dev, size);
 166 }
 167
 168 void i915_gem_stolen_cleanup_compression(struct drm_device *dev)
 169 {
 170         struct drm_i915_private *dev_priv = dev->dev_private;
 171
 172         if (dev_priv->fbc.size == 0)
 173                 return;
 174
 175         if (dev_priv->fbc.compressed_fb) {
 176                 drm_mm_remove_node(dev_priv->fbc.compressed_fb);
 177                 kfree(dev_priv->fbc.compressed_fb);
 178         }
 179
 180         if (dev_priv->fbc.compressed_llb) {
 181                 drm_mm_remove_node(dev_priv->fbc.compressed_llb);
 182                 kfree(dev_priv->fbc.compressed_llb);
 183         }
 184
 185         dev_priv->fbc.size = 0;
 186 }
 187
 188 void i915_gem_cleanup_stolen(struct drm_device *dev)
 189 {
 190         struct drm_i915_private *dev_priv = dev->dev_private;
 191
 192         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 193                 return;
 194
 195         i915_gem_stolen_cleanup_compression(dev);
 196         drm_mm_takedown(&dev_priv->mm.stolen);
 197 }
 198
 199 int i915_gem_init_stolen(struct drm_device *dev)
 200 {
 201         struct drm_i915_private *dev_priv = dev->dev_private;
 202         int bios_reserved = 0;
 203
 204         dev_priv->mm.stolen_base = i915_stolen_to_physical(dev);
 205         if (dev_priv->mm.stolen_base == 0)
 206                 return 0;
 207
 208         DRM_DEBUG_KMS("found %zd bytes of stolen memory at %08lx\n",
 209                       dev_priv->gtt.stolen_size, dev_priv->mm.stolen_base);
 210
 211         if (IS_VALLEYVIEW(dev))
 212                 bios_reserved = 1024*1024; /* top 1M on VLV/BYT */
 213
 214         if (WARN_ON(bios_reserved > dev_priv->gtt.stolen_size))
 215                 return 0;
 216
 217         /* Basic memrange allocator for stolen space */
 218         drm_mm_init(&dev_priv->mm.stolen, 0, dev_priv->gtt.stolen_size -
 219                     bios_reserved);
 220
 221         return 0;
 222 }
 223
 224 static struct sg_table *
 225 i915_pages_create_for_stolen(struct drm_device *dev,
 226                              u32 offset, u32 size)
 227 {
 228         struct drm_i915_private *dev_priv = dev->dev_private;
 229         struct sg_table *st;
 230         struct scatterlist *sg;
 231
 232         DRM_DEBUG_DRIVER("offset=0x%x, size=%d\n", offset, size);
 233         BUG_ON(offset > dev_priv->gtt.stolen_size - size);
 234
 235         /* We hide that we have no struct page backing our stolen object
 236          * by wrapping the contiguous physical allocation with a fake
 237          * dma mapping in a single scatterlist.
 238          */
 239
 240         st = kmalloc(sizeof(*st), GFP_KERNEL);
 241         if (st == NULL)
 242                 return NULL;
 243
 244         if (sg_alloc_table(st, 1, GFP_KERNEL)) {
 245                 kfree(st);
 246                 return NULL;
 247         }
 248
 249         sg = st->sgl;
 250         sg->offset = offset;
 251         sg->length = size;
 252
 253         sg_dma_address(sg) = (dma_addr_t)dev_priv->mm.stolen_base + offset;
 254         sg_dma_len(sg) = size;
 255
 256         return st;
 257 }
 258
 259 static int i915_gem_object_get_pages_stolen(struct drm_i915_gem_object *obj)
 260 {
 261         BUG();
 262         return -EINVAL;
 263 }
 264
 265 static void i915_gem_object_put_pages_stolen(struct drm_i915_gem_object *obj)
 266 {
 267         /* Should only be called during free */
 268         sg_free_table(obj->pages);
 269         kfree(obj->pages);
 270 }
 271
 272 static const struct drm_i915_gem_object_ops i915_gem_object_stolen_ops = {
 273         .get_pages = i915_gem_object_get_pages_stolen,
 274         .put_pages = i915_gem_object_put_pages_stolen,
 275 };
 276
 277 static struct drm_i915_gem_object *
 278 _i915_gem_object_create_stolen(struct drm_device *dev,
 279                                struct drm_mm_node *stolen)
 280 {
 281         struct drm_i915_gem_object *obj;
 282
 283         obj = i915_gem_object_alloc(dev);
 284         if (obj == NULL)
 285                 return NULL;
 286
 287         drm_gem_private_object_init(dev, &obj->base, stolen->size);
 288         i915_gem_object_init(obj, &i915_gem_object_stolen_ops);
 289
 290         obj->pages = i915_pages_create_for_stolen(dev,
 291                                                   stolen->start, stolen->size);
 292         if (obj->pages == NULL)
 293                 goto cleanup;
 294
 295         obj->has_dma_mapping = true;
 296         i915_gem_object_pin_pages(obj);
 297         obj->stolen = stolen;
 298
 299         obj->base.write_domain = I915_GEM_DOMAIN_GTT;
 300         obj->base.read_domains = I915_GEM_DOMAIN_GTT;
 301         obj->cache_level = I915_CACHE_NONE;
 302
 303         return obj;
 304
 305 cleanup:
 306         i915_gem_object_free(obj);
 307         return NULL;
 308 }
 309
 310 struct drm_i915_gem_object *
 311 i915_gem_object_create_stolen(struct drm_device *dev, u32 size)
 312 {
 313         struct drm_i915_private *dev_priv = dev->dev_private;
 314         struct drm_i915_gem_object *obj;
 315         struct drm_mm_node *stolen;
 316         int ret;
 317
 318         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 319                 return NULL;
 320
 321         DRM_DEBUG_KMS("creating stolen object: size=%x\n", size);
 322         if (size == 0)
 323                 return NULL;
 324
 325         stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
 326         if (!stolen)
 327                 return NULL;
 328
 329         ret = drm_mm_insert_node(&dev_priv->mm.stolen, stolen, size,
 330                                  4096, DRM_MM_SEARCH_DEFAULT);
 331         if (ret) {
 332                 kfree(stolen);
 333                 return NULL;
 334         }
 335
 336         obj = _i915_gem_object_create_stolen(dev, stolen);
 337         if (obj)
 338                 return obj;
 339
 340         drm_mm_remove_node(stolen);
 341         kfree(stolen);
 342         return NULL;
 343 }
 344
 345 struct drm_i915_gem_object *
 346 i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
 347                                                u32 stolen_offset,
 348                                                u32 gtt_offset,
 349                                                u32 size)
 350 {
 351         struct drm_i915_private *dev_priv = dev->dev_private;
 352         struct i915_address_space *ggtt = &dev_priv->gtt.base;
 353         struct drm_i915_gem_object *obj;
 354         struct drm_mm_node *stolen;
 355         struct i915_vma *vma;
 356         int ret;
 357
 358         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 359                 return NULL;
 360
 361         DRM_DEBUG_KMS("creating preallocated stolen object: stolen_offset=%x, gtt_offset=%x, size=%x\n",
 362                         stolen_offset, gtt_offset, size);
 363
 364         /* KISS and expect everything to be page-aligned */
 365         BUG_ON(stolen_offset & 4095);
 366         BUG_ON(size & 4095);
 367
 368         if (WARN_ON(size == 0))
 369                 return NULL;
 370
 371         stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
 372         if (!stolen)
 373                 return NULL;
 374
 375         stolen->start = stolen_offset;
 376         stolen->size = size;
 377         ret = drm_mm_reserve_node(&dev_priv->mm.stolen, stolen);
 378         if (ret) {
 379                 DRM_DEBUG_KMS("failed to allocate stolen space\n");
 380                 kfree(stolen);
 381                 return NULL;
 382         }
 383
 384         obj = _i915_gem_object_create_stolen(dev, stolen);
 385         if (obj == NULL) {
 386                 DRM_DEBUG_KMS("failed to allocate stolen object\n");
 387                 drm_mm_remove_node(stolen);
 388                 kfree(stolen);
 389                 return NULL;
 390         }
 391
 392         /* Some objects just need physical mem from stolen space */
 393         if (gtt_offset == I915_GTT_OFFSET_NONE)
 394                 return obj;
 395
 396         vma = i915_gem_vma_create(obj, ggtt);
 397         if (IS_ERR(vma)) {
 398                 ret = PTR_ERR(vma);
 399                 goto err_out;
 400         }
 401
 402         /* To simplify the initialisation sequence between KMS and GTT,
 403          * we allow construction of the stolen object prior to
 404          * setting up the GTT space. The actual reservation will occur
 405          * later.
 406          */
 407         vma->node.start = gtt_offset;
 408         vma->node.size = size;
 409         if (drm_mm_initialized(&ggtt->mm)) {
 410                 ret = drm_mm_reserve_node(&ggtt->mm, &vma->node);
 411                 if (ret) {
 412                         DRM_DEBUG_KMS("failed to allocate stolen GTT space\n");
 413                         i915_gem_vma_destroy(vma);
 414                         goto err_out;
 415                 }
 416         }
 417
 418         obj->has_global_gtt_mapping = 1;
 419
 420         list_add_tail(&obj->global_list, &dev_priv->mm.bound_list);
 421         list_add_tail(&vma->mm_list, &ggtt->inactive_list);
 422
 423         return obj;
 424
 425 err_out:
 426         drm_mm_remove_node(stolen);
 427         kfree(stolen);
 428         drm_gem_object_unreference(&obj->base);
 429         return NULL;
 430 }
 431
 432 void
 433 i915_gem_object_release_stolen(struct drm_i915_gem_object *obj)
 434 {
 435         if (obj->stolen) {
 436                 drm_mm_remove_node(obj->stolen);
 437                 kfree(obj->stolen);
 438                 obj->stolen = NULL;
 439         }
 440 }