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 find_compression_threshold(struct drm_device *dev, 152 struct drm_mm_node *node, 153 int size, 154 int fb_cpp) 155 { 156 struct drm_i915_private *dev_priv = dev->dev_private; 157 int compression_threshold = 1; 158 int ret; 159 160 /* HACK: This code depends on what we will do in *_enable_fbc. If that 161 * code changes, this code needs to change as well. 162 * 163 * The enable_fbc code will attempt to use one of our 2 compression 164 * thresholds, therefore, in that case, we only have 1 resort. 165 */ 166 167 /* Try to over-allocate to reduce reallocations and fragmentation. */ 168 ret = drm_mm_insert_node(&dev_priv->mm.stolen, node, 169 size <<= 1, 4096, DRM_MM_SEARCH_DEFAULT); 170 if (ret == 0) 171 return compression_threshold; 172 173 again: 174 /* HW's ability to limit the CFB is 1:4 */ 175 if (compression_threshold > 4 || 176 (fb_cpp == 2 && compression_threshold == 2)) 177 return 0; 178 179 ret = drm_mm_insert_node(&dev_priv->mm.stolen, node, 180 size >>= 1, 4096, 181 DRM_MM_SEARCH_DEFAULT); 182 if (ret && INTEL_INFO(dev)->gen <= 4) { 183 return 0; 184 } else if (ret) { 185 compression_threshold <<= 1; 186 goto again; 187 } else { 188 return compression_threshold; 189 } 190 } 191 192 static int i915_setup_compression(struct drm_device *dev, int size, int fb_cpp) 193 { 194 struct drm_i915_private *dev_priv = dev->dev_private; 195 struct drm_mm_node *compressed_llb; 196 int ret; 197 198 ret = find_compression_threshold(dev, &dev_priv->fbc.compressed_fb, 199 size, fb_cpp); 200 if (!ret) 201 goto err_llb; 202 else if (ret > 1) { 203 DRM_INFO("Reducing the compressed framebuffer size. This may lead to less power savings than a non-reduced-size. Try to increase stolen memory size if available in BIOS.\n"); 204 205 } 206 207 dev_priv->fbc.threshold = ret; 208 209 if (HAS_PCH_SPLIT(dev)) 210 I915_WRITE(ILK_DPFC_CB_BASE, dev_priv->fbc.compressed_fb.start); 211 else if (IS_GM45(dev)) { 212 I915_WRITE(DPFC_CB_BASE, dev_priv->fbc.compressed_fb.start); 213 } else { 214 compressed_llb = kzalloc(sizeof(*compressed_llb), GFP_KERNEL); 215 if (!compressed_llb) 216 goto err_fb; 217 218 ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_llb, 219 4096, 4096, DRM_MM_SEARCH_DEFAULT); 220 if (ret) 221 goto err_fb; 222 223 dev_priv->fbc.compressed_llb = compressed_llb; 224 225 I915_WRITE(FBC_CFB_BASE, 226 dev_priv->mm.stolen_base + dev_priv->fbc.compressed_fb.start); 227 I915_WRITE(FBC_LL_BASE, 228 dev_priv->mm.stolen_base + compressed_llb->start); 229 } 230 231 dev_priv->fbc.size = size / dev_priv->fbc.threshold; 232 233 DRM_DEBUG_KMS("reserved %d bytes of contiguous stolen space for FBC\n", 234 size); 235 236 return 0; 237 238 err_fb: 239 kfree(compressed_llb); 240 drm_mm_remove_node(&dev_priv->fbc.compressed_fb); 241 err_llb: 242 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); 243 return -ENOSPC; 244 } 245 246 int i915_gem_stolen_setup_compression(struct drm_device *dev, int size, int fb_cpp) 247 { 248 struct drm_i915_private *dev_priv = dev->dev_private; 249 250 if (!drm_mm_initialized(&dev_priv->mm.stolen)) 251 return -ENODEV; 252 253 if (size < dev_priv->fbc.size) 254 return 0; 255 256 /* Release any current block */ 257 i915_gem_stolen_cleanup_compression(dev); 258 259 return i915_setup_compression(dev, size, fb_cpp); 260 } 261 262 void i915_gem_stolen_cleanup_compression(struct drm_device *dev) 263 { 264 struct drm_i915_private *dev_priv = dev->dev_private; 265 266 if (dev_priv->fbc.size == 0) 267 return; 268 269 drm_mm_remove_node(&dev_priv->fbc.compressed_fb); 270 271 if (dev_priv->fbc.compressed_llb) { 272 drm_mm_remove_node(dev_priv->fbc.compressed_llb); 273 kfree(dev_priv->fbc.compressed_llb); 274 } 275 276 dev_priv->fbc.size = 0; 277 } 278 279 void i915_gem_cleanup_stolen(struct drm_device *dev) 280 { 281 struct drm_i915_private *dev_priv = dev->dev_private; 282 283 if (!drm_mm_initialized(&dev_priv->mm.stolen)) 284 return; 285 286 i915_gem_stolen_cleanup_compression(dev); 287 drm_mm_takedown(&dev_priv->mm.stolen); 288 } 289 290 int i915_gem_init_stolen(struct drm_device *dev) 291 { 292 struct drm_i915_private *dev_priv = dev->dev_private; 293 int bios_reserved = 0; 294 295 #ifdef CONFIG_INTEL_IOMMU 296 if (intel_iommu_gfx_mapped && INTEL_INFO(dev)->gen < 8) { 297 DRM_INFO("DMAR active, disabling use of stolen memory\n"); 298 return 0; 299 } 300 #endif 301 302 if (dev_priv->gtt.stolen_size == 0) 303 return 0; 304 305 dev_priv->mm.stolen_base = i915_stolen_to_physical(dev); 306 if (dev_priv->mm.stolen_base == 0) 307 return 0; 308 309 DRM_DEBUG_KMS("found %zd bytes of stolen memory at %08lx\n", 310 dev_priv->gtt.stolen_size, dev_priv->mm.stolen_base); 311 312 if (IS_VALLEYVIEW(dev)) 313 bios_reserved = 1024*1024; /* top 1M on VLV/BYT */ 314 315 if (WARN_ON(bios_reserved > dev_priv->gtt.stolen_size)) 316 return 0; 317 318 /* Basic memrange allocator for stolen space */ 319 drm_mm_init(&dev_priv->mm.stolen, 0, dev_priv->gtt.stolen_size - 320 bios_reserved); 321 322 return 0; 323 } 324 325 #if 0 326 static struct sg_table * 327 i915_pages_create_for_stolen(struct drm_device *dev, 328 u32 offset, u32 size) 329 { 330 struct drm_i915_private *dev_priv = dev->dev_private; 331 struct sg_table *st; 332 struct scatterlist *sg; 333 334 DRM_DEBUG_DRIVER("offset=0x%x, size=%d\n", offset, size); 335 BUG_ON(offset > dev_priv->gtt.stolen_size - size); 336 337 /* We hide that we have no struct page backing our stolen object 338 * by wrapping the contiguous physical allocation with a fake 339 * dma mapping in a single scatterlist. 340 */ 341 342 st = kmalloc(sizeof(*st), GFP_KERNEL); 343 if (st == NULL) 344 return NULL; 345 346 if (sg_alloc_table(st, 1, GFP_KERNEL)) { 347 kfree(st); 348 return NULL; 349 } 350 351 sg = st->sgl; 352 sg->offset = 0; 353 sg->length = size; 354 355 sg_dma_address(sg) = (dma_addr_t)dev_priv->mm.stolen_base + offset; 356 sg_dma_len(sg) = size; 357 358 return st; 359 } 360 #endif 361 362 static int i915_gem_object_get_pages_stolen(struct drm_i915_gem_object *obj) 363 { 364 BUG(); 365 return -EINVAL; 366 } 367 368 static void i915_gem_object_put_pages_stolen(struct drm_i915_gem_object *obj) 369 { 370 #if 0 371 /* Should only be called during free */ 372 sg_free_table(obj->pages); 373 kfree(obj->pages); 374 #else 375 BUG(); 376 #endif 377 } 378 379 380 static void 381 i915_gem_object_release_stolen(struct drm_i915_gem_object *obj) 382 { 383 if (obj->stolen) { 384 drm_mm_remove_node(obj->stolen); 385 kfree(obj->stolen); 386 obj->stolen = NULL; 387 } 388 } 389 static const struct drm_i915_gem_object_ops i915_gem_object_stolen_ops = { 390 .get_pages = i915_gem_object_get_pages_stolen, 391 .put_pages = i915_gem_object_put_pages_stolen, 392 .release = i915_gem_object_release_stolen, 393 }; 394 395 static struct drm_i915_gem_object * 396 _i915_gem_object_create_stolen(struct drm_device *dev, 397 struct drm_mm_node *stolen) 398 { 399 struct drm_i915_gem_object *obj; 400 401 #if 0 402 obj = i915_gem_object_alloc(dev); 403 #else 404 obj = NULL; 405 #endif 406 if (obj == NULL) 407 return NULL; 408 409 drm_gem_private_object_init(dev, &obj->base, stolen->size); 410 i915_gem_object_init(obj, &i915_gem_object_stolen_ops); 411 412 #if 0 413 obj->pages = i915_pages_create_for_stolen(dev, 414 stolen->start, stolen->size); 415 #else 416 obj->pages = NULL; 417 #endif 418 if (obj->pages == NULL) 419 goto cleanup; 420 421 obj->has_dma_mapping = true; 422 i915_gem_object_pin_pages(obj); 423 obj->stolen = stolen; 424 425 obj->base.read_domains = I915_GEM_DOMAIN_CPU | I915_GEM_DOMAIN_GTT; 426 obj->cache_level = HAS_LLC(dev) ? I915_CACHE_LLC : I915_CACHE_NONE; 427 428 return obj; 429 430 cleanup: 431 i915_gem_object_free(obj); 432 return NULL; 433 } 434 435 struct drm_i915_gem_object * 436 i915_gem_object_create_stolen(struct drm_device *dev, u32 size) 437 { 438 struct drm_i915_private *dev_priv = dev->dev_private; 439 struct drm_i915_gem_object *obj; 440 struct drm_mm_node *stolen; 441 int ret; 442 443 if (!drm_mm_initialized(&dev_priv->mm.stolen)) 444 return NULL; 445 446 DRM_DEBUG_KMS("creating stolen object: size=%x\n", size); 447 if (size == 0) 448 return NULL; 449 450 stolen = kzalloc(sizeof(*stolen), GFP_KERNEL); 451 if (!stolen) 452 return NULL; 453 454 ret = drm_mm_insert_node(&dev_priv->mm.stolen, stolen, size, 455 4096, DRM_MM_SEARCH_DEFAULT); 456 if (ret) { 457 kfree(stolen); 458 return NULL; 459 } 460 461 obj = _i915_gem_object_create_stolen(dev, stolen); 462 if (obj) 463 return obj; 464 465 drm_mm_remove_node(stolen); 466 kfree(stolen); 467 return NULL; 468 } 469 470 struct drm_i915_gem_object * 471 i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev, 472 u32 stolen_offset, 473 u32 gtt_offset, 474 u32 size) 475 { 476 struct drm_i915_private *dev_priv = dev->dev_private; 477 struct i915_address_space *ggtt = &dev_priv->gtt.base; 478 struct drm_i915_gem_object *obj; 479 struct drm_mm_node *stolen; 480 struct i915_vma *vma; 481 int ret; 482 483 if (!drm_mm_initialized(&dev_priv->mm.stolen)) 484 return NULL; 485 486 DRM_DEBUG_KMS("creating preallocated stolen object: stolen_offset=%x, gtt_offset=%x, size=%x\n", 487 stolen_offset, gtt_offset, size); 488 489 /* KISS and expect everything to be page-aligned */ 490 BUG_ON(stolen_offset & 4095); 491 BUG_ON(size & 4095); 492 493 if (WARN_ON(size == 0)) 494 return NULL; 495 496 stolen = kzalloc(sizeof(*stolen), GFP_KERNEL); 497 if (!stolen) 498 return NULL; 499 500 stolen->start = stolen_offset; 501 stolen->size = size; 502 ret = drm_mm_reserve_node(&dev_priv->mm.stolen, stolen); 503 if (ret) { 504 DRM_DEBUG_KMS("failed to allocate stolen space\n"); 505 kfree(stolen); 506 return NULL; 507 } 508 509 obj = _i915_gem_object_create_stolen(dev, stolen); 510 if (obj == NULL) { 511 DRM_DEBUG_KMS("failed to allocate stolen object\n"); 512 drm_mm_remove_node(stolen); 513 kfree(stolen); 514 return NULL; 515 } 516 517 /* Some objects just need physical mem from stolen space */ 518 if (gtt_offset == I915_GTT_OFFSET_NONE) 519 return obj; 520 521 vma = i915_gem_obj_lookup_or_create_vma(obj, ggtt); 522 if (IS_ERR(vma)) { 523 ret = PTR_ERR(vma); 524 goto err_out; 525 } 526 527 /* To simplify the initialisation sequence between KMS and GTT, 528 * we allow construction of the stolen object prior to 529 * setting up the GTT space. The actual reservation will occur 530 * later. 531 */ 532 vma->node.start = gtt_offset; 533 vma->node.size = size; 534 if (drm_mm_initialized(&ggtt->mm)) { 535 ret = drm_mm_reserve_node(&ggtt->mm, &vma->node); 536 if (ret) { 537 DRM_DEBUG_KMS("failed to allocate stolen GTT space\n"); 538 goto err_vma; 539 } 540 } 541 542 obj->has_global_gtt_mapping = 1; 543 544 list_add_tail(&obj->global_list, &dev_priv->mm.bound_list); 545 list_add_tail(&vma->mm_list, &ggtt->inactive_list); 546 i915_gem_object_pin_pages(obj); 547 548 return obj; 549 550 err_vma: 551 i915_gem_vma_destroy(vma); 552 err_out: 553 drm_mm_remove_node(stolen); 554 kfree(stolen); 555 drm_gem_object_unreference(&obj->base); 556 return NULL; 557 } 558