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 45static 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 /* make sure we don't clobber the GTT if it's within stolen memory */ 78 if (INTEL_INFO(dev)->gen <= 4 && !IS_G33(dev) && !IS_G4X(dev)) { 79 struct { 80 u32 start, end; 81 } stolen[2] = { 82 { .start = base, .end = base + dev_priv->gtt.stolen_size, }, 83 { .start = base, .end = base + dev_priv->gtt.stolen_size, }, 84 }; 85 u64 gtt_start, gtt_end; 86 87 gtt_start = I915_READ(PGTBL_CTL); 88 if (IS_GEN4(dev)) 89 gtt_start = (gtt_start & PGTBL_ADDRESS_LO_MASK) | 90 (gtt_start & PGTBL_ADDRESS_HI_MASK) << 28; 91 else 92 gtt_start &= PGTBL_ADDRESS_LO_MASK; 93 gtt_end = gtt_start + gtt_total_entries(dev_priv->gtt) * 4; 94 95 if (gtt_start >= stolen[0].start && gtt_start < stolen[0].end) 96 stolen[0].end = gtt_start; 97 if (gtt_end > stolen[1].start && gtt_end <= stolen[1].end) 98 stolen[1].start = gtt_end; 99 100 /* pick the larger of the two chunks */ 101 if (stolen[0].end - stolen[0].start > 102 stolen[1].end - stolen[1].start) { 103 base = stolen[0].start; 104 dev_priv->gtt.stolen_size = stolen[0].end - stolen[0].start; 105 } else { 106 base = stolen[1].start; 107 dev_priv->gtt.stolen_size = stolen[1].end - stolen[1].start; 108 } 109 110 if (stolen[0].start != stolen[1].start || 111 stolen[0].end != stolen[1].end) { 112 DRM_DEBUG_KMS("GTT within stolen memory at 0x%llx-0x%llx\n", 113 (unsigned long long) gtt_start, 114 (unsigned long long) gtt_end - 1); 115 DRM_DEBUG_KMS("Stolen memory adjusted to 0x%x-0x%x\n", 116 base, base + (u32) dev_priv->gtt.stolen_size - 1); 117 } 118 } 119 120 121 /* Verify that nothing else uses this physical address. Stolen 122 * memory should be reserved by the BIOS and hidden from the 123 * kernel. So if the region is already marked as busy, something 124 * is seriously wrong. 125 */ 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 /* 141 * GEN3 firmware likes to smash pci bridges into the stolen 142 * range. Apparently this works. 143 */ 144 if (r == NULL && !IS_GEN3(dev)) { 145 DRM_ERROR("conflict detected with stolen region: [0x%08x - 0x%08x]\n", 146 base, base + (uint32_t)dev_priv->gtt.stolen_size); 147 base = 0; 148 } 149 } 150 151 return base; 152} 153 154static int find_compression_threshold(struct drm_device *dev, 155 struct drm_mm_node *node, 156 int size, 157 int fb_cpp) 158{ 159 struct drm_i915_private *dev_priv = dev->dev_private; 160 int compression_threshold = 1; 161 int ret; 162 163 /* HACK: This code depends on what we will do in *_enable_fbc. If that 164 * code changes, this code needs to change as well. 165 * 166 * The enable_fbc code will attempt to use one of our 2 compression 167 * thresholds, therefore, in that case, we only have 1 resort. 168 */ 169 170 /* Try to over-allocate to reduce reallocations and fragmentation. */ 171 ret = drm_mm_insert_node(&dev_priv->mm.stolen, node, 172 size <<= 1, 4096, DRM_MM_SEARCH_DEFAULT); 173 if (ret == 0) 174 return compression_threshold; 175 176again: 177 /* HW's ability to limit the CFB is 1:4 */ 178 if (compression_threshold > 4 || 179 (fb_cpp == 2 && compression_threshold == 2)) 180 return 0; 181 182 ret = drm_mm_insert_node(&dev_priv->mm.stolen, node, 183 size >>= 1, 4096, 184 DRM_MM_SEARCH_DEFAULT); 185 if (ret && INTEL_INFO(dev)->gen <= 4) { 186 return 0; 187 } else if (ret) { 188 compression_threshold <<= 1; 189 goto again; 190 } else { 191 return compression_threshold; 192 } 193} 194 195static int i915_setup_compression(struct drm_device *dev, int size, int fb_cpp) 196{ 197 struct drm_i915_private *dev_priv = dev->dev_private; 198 struct drm_mm_node *uninitialized_var(compressed_llb); 199 int ret; 200 201 ret = find_compression_threshold(dev, &dev_priv->fbc.compressed_fb, 202 size, fb_cpp); 203 if (!ret) 204 goto err_llb; 205 else if (ret > 1) { 206 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"); 207 208 } 209 210 dev_priv->fbc.threshold = ret; 211 212 if (HAS_PCH_SPLIT(dev)) 213 I915_WRITE(ILK_DPFC_CB_BASE, dev_priv->fbc.compressed_fb.start); 214 else if (IS_GM45(dev)) { 215 I915_WRITE(DPFC_CB_BASE, dev_priv->fbc.compressed_fb.start); 216 } else { 217 compressed_llb = kzalloc(sizeof(*compressed_llb), GFP_KERNEL); 218 if (!compressed_llb) 219 goto err_fb; 220 221 ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_llb, 222 4096, 4096, DRM_MM_SEARCH_DEFAULT); 223 if (ret) 224 goto err_fb; 225 226 dev_priv->fbc.compressed_llb = compressed_llb; 227 228 I915_WRITE(FBC_CFB_BASE, 229 dev_priv->mm.stolen_base + dev_priv->fbc.compressed_fb.start); 230 I915_WRITE(FBC_LL_BASE, 231 dev_priv->mm.stolen_base + compressed_llb->start); 232 } 233 234 dev_priv->fbc.uncompressed_size = size; 235 236 DRM_DEBUG_KMS("reserved %d bytes of contiguous stolen space for FBC\n", 237 size); 238 239 return 0; 240 241err_fb: 242 kfree(compressed_llb); 243 drm_mm_remove_node(&dev_priv->fbc.compressed_fb); 244err_llb: 245 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); 246 return -ENOSPC; 247} 248 249int i915_gem_stolen_setup_compression(struct drm_device *dev, int size, int fb_cpp) 250{ 251 struct drm_i915_private *dev_priv = dev->dev_private; 252 253 if (!drm_mm_initialized(&dev_priv->mm.stolen)) 254 return -ENODEV; 255 256 if (size <= dev_priv->fbc.uncompressed_size) 257 return 0; 258 259 /* Release any current block */ 260 i915_gem_stolen_cleanup_compression(dev); 261 262 return i915_setup_compression(dev, size, fb_cpp); 263} 264 265void i915_gem_stolen_cleanup_compression(struct drm_device *dev) 266{ 267 struct drm_i915_private *dev_priv = dev->dev_private; 268 269 if (dev_priv->fbc.uncompressed_size == 0) 270 return; 271 272 drm_mm_remove_node(&dev_priv->fbc.compressed_fb); 273 274 if (dev_priv->fbc.compressed_llb) { 275 drm_mm_remove_node(dev_priv->fbc.compressed_llb); 276 kfree(dev_priv->fbc.compressed_llb); 277 } 278 279 dev_priv->fbc.uncompressed_size = 0; 280} 281 282void i915_gem_cleanup_stolen(struct drm_device *dev) 283{ 284 struct drm_i915_private *dev_priv = dev->dev_private; 285 286 if (!drm_mm_initialized(&dev_priv->mm.stolen)) 287 return; 288 289 i915_gem_stolen_cleanup_compression(dev); 290 drm_mm_takedown(&dev_priv->mm.stolen); 291} 292 293int i915_gem_init_stolen(struct drm_device *dev) 294{ 295 struct drm_i915_private *dev_priv = dev->dev_private; 296 u32 tmp; 297 int bios_reserved = 0; 298 299#ifdef CONFIG_INTEL_IOMMU 300 if (intel_iommu_gfx_mapped && INTEL_INFO(dev)->gen < 8) { 301 DRM_INFO("DMAR active, disabling use of stolen memory\n"); 302 return 0; 303 } 304#endif 305 306 if (dev_priv->gtt.stolen_size == 0) 307 return 0; 308 309 dev_priv->mm.stolen_base = i915_stolen_to_physical(dev); 310 if (dev_priv->mm.stolen_base == 0) 311 return 0; 312 313 DRM_DEBUG_KMS("found %zd bytes of stolen memory at %08lx\n", 314 dev_priv->gtt.stolen_size, dev_priv->mm.stolen_base); 315 316 if (INTEL_INFO(dev)->gen >= 8) { 317 tmp = I915_READ(GEN7_BIOS_RESERVED); 318 tmp >>= GEN8_BIOS_RESERVED_SHIFT; 319 tmp &= GEN8_BIOS_RESERVED_MASK; 320 bios_reserved = (1024*1024) << tmp; 321 } else if (IS_GEN7(dev)) { 322 tmp = I915_READ(GEN7_BIOS_RESERVED); 323 bios_reserved = tmp & GEN7_BIOS_RESERVED_256K ? 324 256*1024 : 1024*1024; 325 } 326 327 if (WARN_ON(bios_reserved > dev_priv->gtt.stolen_size)) 328 return 0; 329 330 /* Basic memrange allocator for stolen space */ 331 drm_mm_init(&dev_priv->mm.stolen, 0, dev_priv->gtt.stolen_size - 332 bios_reserved); 333 334 return 0; 335} 336 337static struct sg_table * 338i915_pages_create_for_stolen(struct drm_device *dev, 339 u32 offset, u32 size) 340{ 341 struct drm_i915_private *dev_priv = dev->dev_private; 342 struct sg_table *st; 343 struct scatterlist *sg; 344 345 DRM_DEBUG_DRIVER("offset=0x%x, size=%d\n", offset, size); 346 BUG_ON(offset > dev_priv->gtt.stolen_size - size); 347 348 /* We hide that we have no struct page backing our stolen object 349 * by wrapping the contiguous physical allocation with a fake 350 * dma mapping in a single scatterlist. 351 */ 352 353 st = kmalloc(sizeof(*st), GFP_KERNEL); 354 if (st == NULL) 355 return NULL; 356 357 if (sg_alloc_table(st, 1, GFP_KERNEL)) { 358 kfree(st); 359 return NULL; 360 } 361 362 sg = st->sgl; 363 sg->offset = 0; 364 sg->length = size; 365 366 sg_dma_address(sg) = (dma_addr_t)dev_priv->mm.stolen_base + offset; 367 sg_dma_len(sg) = size; 368 369 return st; 370} 371 372static int i915_gem_object_get_pages_stolen(struct drm_i915_gem_object *obj) 373{ 374 BUG(); 375 return -EINVAL; 376} 377 378static void i915_gem_object_put_pages_stolen(struct drm_i915_gem_object *obj) 379{ 380 /* Should only be called during free */ 381 sg_free_table(obj->pages); 382 kfree(obj->pages); 383} 384 385 386static void 387i915_gem_object_release_stolen(struct drm_i915_gem_object *obj) 388{ 389 if (obj->stolen) { 390 drm_mm_remove_node(obj->stolen); 391 kfree(obj->stolen); 392 obj->stolen = NULL; 393 } 394} 395static const struct drm_i915_gem_object_ops i915_gem_object_stolen_ops = { 396 .get_pages = i915_gem_object_get_pages_stolen, 397 .put_pages = i915_gem_object_put_pages_stolen, 398 .release = i915_gem_object_release_stolen, 399}; 400 401static struct drm_i915_gem_object * 402_i915_gem_object_create_stolen(struct drm_device *dev, 403 struct drm_mm_node *stolen) 404{ 405 struct drm_i915_gem_object *obj; 406 407 obj = i915_gem_object_alloc(dev); 408 if (obj == NULL) 409 return NULL; 410 411 drm_gem_private_object_init(dev, &obj->base, stolen->size); 412 i915_gem_object_init(obj, &i915_gem_object_stolen_ops); 413 414 obj->pages = i915_pages_create_for_stolen(dev, 415 stolen->start, stolen->size); 416 if (obj->pages == NULL) 417 goto cleanup; 418 419 obj->has_dma_mapping = true; 420 i915_gem_object_pin_pages(obj); 421 obj->stolen = stolen; 422 423 obj->base.read_domains = I915_GEM_DOMAIN_CPU | I915_GEM_DOMAIN_GTT; 424 obj->cache_level = HAS_LLC(dev) ? I915_CACHE_LLC : I915_CACHE_NONE; 425 426 return obj; 427 428cleanup: 429 i915_gem_object_free(obj); 430 return NULL; 431} 432 433struct drm_i915_gem_object * 434i915_gem_object_create_stolen(struct drm_device *dev, u32 size) 435{ 436 struct drm_i915_private *dev_priv = dev->dev_private; 437 struct drm_i915_gem_object *obj; 438 struct drm_mm_node *stolen; 439 int ret; 440 441 if (!drm_mm_initialized(&dev_priv->mm.stolen)) 442 return NULL; 443 444 DRM_DEBUG_KMS("creating stolen object: size=%x\n", size); 445 if (size == 0) 446 return NULL; 447 448 stolen = kzalloc(sizeof(*stolen), GFP_KERNEL); 449 if (!stolen) 450 return NULL; 451 452 ret = drm_mm_insert_node(&dev_priv->mm.stolen, stolen, size, 453 4096, DRM_MM_SEARCH_DEFAULT); 454 if (ret) { 455 kfree(stolen); 456 return NULL; 457 } 458 459 obj = _i915_gem_object_create_stolen(dev, stolen); 460 if (obj) 461 return obj; 462 463 drm_mm_remove_node(stolen); 464 kfree(stolen); 465 return NULL; 466} 467 468struct drm_i915_gem_object * 469i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev, 470 u32 stolen_offset, 471 u32 gtt_offset, 472 u32 size) 473{ 474 struct drm_i915_private *dev_priv = dev->dev_private; 475 struct i915_address_space *ggtt = &dev_priv->gtt.base; 476 struct drm_i915_gem_object *obj; 477 struct drm_mm_node *stolen; 478 struct i915_vma *vma; 479 int ret; 480 481 if (!drm_mm_initialized(&dev_priv->mm.stolen)) 482 return NULL; 483 484 DRM_DEBUG_KMS("creating preallocated stolen object: stolen_offset=%x, gtt_offset=%x, size=%x\n", 485 stolen_offset, gtt_offset, size); 486 487 /* KISS and expect everything to be page-aligned */ 488 if (WARN_ON(size == 0) || WARN_ON(size & 4095) || 489 WARN_ON(stolen_offset & 4095)) 490 return NULL; 491 492 stolen = kzalloc(sizeof(*stolen), GFP_KERNEL); 493 if (!stolen) 494 return NULL; 495 496 stolen->start = stolen_offset; 497 stolen->size = size; 498 ret = drm_mm_reserve_node(&dev_priv->mm.stolen, stolen); 499 if (ret) { 500 DRM_DEBUG_KMS("failed to allocate stolen space\n"); 501 kfree(stolen); 502 return NULL; 503 } 504 505 obj = _i915_gem_object_create_stolen(dev, stolen); 506 if (obj == NULL) { 507 DRM_DEBUG_KMS("failed to allocate stolen object\n"); 508 drm_mm_remove_node(stolen); 509 kfree(stolen); 510 return NULL; 511 } 512 513 /* Some objects just need physical mem from stolen space */ 514 if (gtt_offset == I915_GTT_OFFSET_NONE) 515 return obj; 516 517 vma = i915_gem_obj_lookup_or_create_vma(obj, ggtt); 518 if (IS_ERR(vma)) { 519 ret = PTR_ERR(vma); 520 goto err_out; 521 } 522 523 /* To simplify the initialisation sequence between KMS and GTT, 524 * we allow construction of the stolen object prior to 525 * setting up the GTT space. The actual reservation will occur 526 * later. 527 */ 528 vma->node.start = gtt_offset; 529 vma->node.size = size; 530 if (drm_mm_initialized(&ggtt->mm)) { 531 ret = drm_mm_reserve_node(&ggtt->mm, &vma->node); 532 if (ret) { 533 DRM_DEBUG_KMS("failed to allocate stolen GTT space\n"); 534 goto err_vma; 535 } 536 } 537 538 vma->bound |= GLOBAL_BIND; 539 540 list_add_tail(&obj->global_list, &dev_priv->mm.bound_list); 541 list_add_tail(&vma->mm_list, &ggtt->inactive_list); 542 i915_gem_object_pin_pages(obj); 543 544 return obj; 545 546err_vma: 547 i915_gem_vma_destroy(vma); 548err_out: 549 drm_mm_remove_node(stolen); 550 kfree(stolen); 551 drm_gem_object_unreference(&obj->base); 552 return NULL; 553} 554