gen8_ppgtt.c revision 1.1.1.1
1 /* $NetBSD: gen8_ppgtt.c,v 1.1.1.1 2021/12/18 20:15:32 riastradh Exp $ */ 2 3 // SPDX-License-Identifier: MIT 4 /* 5 * Copyright 2020 Intel Corporation 6 */ 7 8 #include <sys/cdefs.h> 9 __KERNEL_RCSID(0, "$NetBSD: gen8_ppgtt.c,v 1.1.1.1 2021/12/18 20:15:32 riastradh Exp $"); 10 11 #include <linux/log2.h> 12 13 #include "gen8_ppgtt.h" 14 #include "i915_scatterlist.h" 15 #include "i915_trace.h" 16 #include "i915_vgpu.h" 17 #include "intel_gt.h" 18 #include "intel_gtt.h" 19 20 static u64 gen8_pde_encode(const dma_addr_t addr, 21 const enum i915_cache_level level) 22 { 23 u64 pde = addr | _PAGE_PRESENT | _PAGE_RW; 24 25 if (level != I915_CACHE_NONE) 26 pde |= PPAT_CACHED_PDE; 27 else 28 pde |= PPAT_UNCACHED; 29 30 return pde; 31 } 32 33 static void gen8_ppgtt_notify_vgt(struct i915_ppgtt *ppgtt, bool create) 34 { 35 struct drm_i915_private *i915 = ppgtt->vm.i915; 36 struct intel_uncore *uncore = ppgtt->vm.gt->uncore; 37 enum vgt_g2v_type msg; 38 int i; 39 40 if (create) 41 atomic_inc(px_used(ppgtt->pd)); /* never remove */ 42 else 43 atomic_dec(px_used(ppgtt->pd)); 44 45 mutex_lock(&i915->vgpu.lock); 46 47 if (i915_vm_is_4lvl(&ppgtt->vm)) { 48 const u64 daddr = px_dma(ppgtt->pd); 49 50 intel_uncore_write(uncore, 51 vgtif_reg(pdp[0].lo), lower_32_bits(daddr)); 52 intel_uncore_write(uncore, 53 vgtif_reg(pdp[0].hi), upper_32_bits(daddr)); 54 55 msg = create ? 56 VGT_G2V_PPGTT_L4_PAGE_TABLE_CREATE : 57 VGT_G2V_PPGTT_L4_PAGE_TABLE_DESTROY; 58 } else { 59 for (i = 0; i < GEN8_3LVL_PDPES; i++) { 60 const u64 daddr = i915_page_dir_dma_addr(ppgtt, i); 61 62 intel_uncore_write(uncore, 63 vgtif_reg(pdp[i].lo), 64 lower_32_bits(daddr)); 65 intel_uncore_write(uncore, 66 vgtif_reg(pdp[i].hi), 67 upper_32_bits(daddr)); 68 } 69 70 msg = create ? 71 VGT_G2V_PPGTT_L3_PAGE_TABLE_CREATE : 72 VGT_G2V_PPGTT_L3_PAGE_TABLE_DESTROY; 73 } 74 75 /* g2v_notify atomically (via hv trap) consumes the message packet. */ 76 intel_uncore_write(uncore, vgtif_reg(g2v_notify), msg); 77 78 mutex_unlock(&i915->vgpu.lock); 79 } 80 81 /* Index shifts into the pagetable are offset by GEN8_PTE_SHIFT [12] */ 82 #define GEN8_PAGE_SIZE (SZ_4K) /* page and page-directory sizes are the same */ 83 #define GEN8_PTE_SHIFT (ilog2(GEN8_PAGE_SIZE)) 84 #define GEN8_PDES (GEN8_PAGE_SIZE / sizeof(u64)) 85 #define gen8_pd_shift(lvl) ((lvl) * ilog2(GEN8_PDES)) 86 #define gen8_pd_index(i, lvl) i915_pde_index((i), gen8_pd_shift(lvl)) 87 #define __gen8_pte_shift(lvl) (GEN8_PTE_SHIFT + gen8_pd_shift(lvl)) 88 #define __gen8_pte_index(a, lvl) i915_pde_index((a), __gen8_pte_shift(lvl)) 89 90 #define as_pd(x) container_of((x), typeof(struct i915_page_directory), pt) 91 92 static inline unsigned int 93 gen8_pd_range(u64 start, u64 end, int lvl, unsigned int *idx) 94 { 95 const int shift = gen8_pd_shift(lvl); 96 const u64 mask = ~0ull << gen8_pd_shift(lvl + 1); 97 98 GEM_BUG_ON(start >= end); 99 end += ~mask >> gen8_pd_shift(1); 100 101 *idx = i915_pde_index(start, shift); 102 if ((start ^ end) & mask) 103 return GEN8_PDES - *idx; 104 else 105 return i915_pde_index(end, shift) - *idx; 106 } 107 108 static inline bool gen8_pd_contains(u64 start, u64 end, int lvl) 109 { 110 const u64 mask = ~0ull << gen8_pd_shift(lvl + 1); 111 112 GEM_BUG_ON(start >= end); 113 return (start ^ end) & mask && (start & ~mask) == 0; 114 } 115 116 static inline unsigned int gen8_pt_count(u64 start, u64 end) 117 { 118 GEM_BUG_ON(start >= end); 119 if ((start ^ end) >> gen8_pd_shift(1)) 120 return GEN8_PDES - (start & (GEN8_PDES - 1)); 121 else 122 return end - start; 123 } 124 125 static inline unsigned int 126 gen8_pd_top_count(const struct i915_address_space *vm) 127 { 128 unsigned int shift = __gen8_pte_shift(vm->top); 129 return (vm->total + (1ull << shift) - 1) >> shift; 130 } 131 132 static inline struct i915_page_directory * 133 gen8_pdp_for_page_index(struct i915_address_space * const vm, const u64 idx) 134 { 135 struct i915_ppgtt * const ppgtt = i915_vm_to_ppgtt(vm); 136 137 if (vm->top == 2) 138 return ppgtt->pd; 139 else 140 return i915_pd_entry(ppgtt->pd, gen8_pd_index(idx, vm->top)); 141 } 142 143 static inline struct i915_page_directory * 144 gen8_pdp_for_page_address(struct i915_address_space * const vm, const u64 addr) 145 { 146 return gen8_pdp_for_page_index(vm, addr >> GEN8_PTE_SHIFT); 147 } 148 149 static void __gen8_ppgtt_cleanup(struct i915_address_space *vm, 150 struct i915_page_directory *pd, 151 int count, int lvl) 152 { 153 if (lvl) { 154 void **pde = pd->entry; 155 156 do { 157 if (!*pde) 158 continue; 159 160 __gen8_ppgtt_cleanup(vm, *pde, GEN8_PDES, lvl - 1); 161 } while (pde++, --count); 162 } 163 164 free_px(vm, pd); 165 } 166 167 static void gen8_ppgtt_cleanup(struct i915_address_space *vm) 168 { 169 struct i915_ppgtt *ppgtt = i915_vm_to_ppgtt(vm); 170 171 if (intel_vgpu_active(vm->i915)) 172 gen8_ppgtt_notify_vgt(ppgtt, false); 173 174 __gen8_ppgtt_cleanup(vm, ppgtt->pd, gen8_pd_top_count(vm), vm->top); 175 free_scratch(vm); 176 } 177 178 static u64 __gen8_ppgtt_clear(struct i915_address_space * const vm, 179 struct i915_page_directory * const pd, 180 u64 start, const u64 end, int lvl) 181 { 182 const struct i915_page_scratch * const scratch = &vm->scratch[lvl]; 183 unsigned int idx, len; 184 185 GEM_BUG_ON(end > vm->total >> GEN8_PTE_SHIFT); 186 187 len = gen8_pd_range(start, end, lvl--, &idx); 188 DBG("%s(%p):{ lvl:%d, start:%llx, end:%llx, idx:%d, len:%d, used:%d }\n", 189 __func__, vm, lvl + 1, start, end, 190 idx, len, atomic_read(px_used(pd))); 191 GEM_BUG_ON(!len || len >= atomic_read(px_used(pd))); 192 193 do { 194 struct i915_page_table *pt = pd->entry[idx]; 195 196 if (atomic_fetch_inc(&pt->used) >> gen8_pd_shift(1) && 197 gen8_pd_contains(start, end, lvl)) { 198 DBG("%s(%p):{ lvl:%d, idx:%d, start:%llx, end:%llx } removing pd\n", 199 __func__, vm, lvl + 1, idx, start, end); 200 clear_pd_entry(pd, idx, scratch); 201 __gen8_ppgtt_cleanup(vm, as_pd(pt), I915_PDES, lvl); 202 start += (u64)I915_PDES << gen8_pd_shift(lvl); 203 continue; 204 } 205 206 if (lvl) { 207 start = __gen8_ppgtt_clear(vm, as_pd(pt), 208 start, end, lvl); 209 } else { 210 unsigned int count; 211 u64 *vaddr; 212 213 count = gen8_pt_count(start, end); 214 DBG("%s(%p):{ lvl:%d, start:%llx, end:%llx, idx:%d, len:%d, used:%d } removing pte\n", 215 __func__, vm, lvl, start, end, 216 gen8_pd_index(start, 0), count, 217 atomic_read(&pt->used)); 218 GEM_BUG_ON(!count || count >= atomic_read(&pt->used)); 219 220 vaddr = kmap_atomic_px(pt); 221 memset64(vaddr + gen8_pd_index(start, 0), 222 vm->scratch[0].encode, 223 count); 224 kunmap_atomic(vaddr); 225 226 atomic_sub(count, &pt->used); 227 start += count; 228 } 229 230 if (release_pd_entry(pd, idx, pt, scratch)) 231 free_px(vm, pt); 232 } while (idx++, --len); 233 234 return start; 235 } 236 237 static void gen8_ppgtt_clear(struct i915_address_space *vm, 238 u64 start, u64 length) 239 { 240 GEM_BUG_ON(!IS_ALIGNED(start, BIT_ULL(GEN8_PTE_SHIFT))); 241 GEM_BUG_ON(!IS_ALIGNED(length, BIT_ULL(GEN8_PTE_SHIFT))); 242 GEM_BUG_ON(range_overflows(start, length, vm->total)); 243 244 start >>= GEN8_PTE_SHIFT; 245 length >>= GEN8_PTE_SHIFT; 246 GEM_BUG_ON(length == 0); 247 248 __gen8_ppgtt_clear(vm, i915_vm_to_ppgtt(vm)->pd, 249 start, start + length, vm->top); 250 } 251 252 static int __gen8_ppgtt_alloc(struct i915_address_space * const vm, 253 struct i915_page_directory * const pd, 254 u64 * const start, const u64 end, int lvl) 255 { 256 const struct i915_page_scratch * const scratch = &vm->scratch[lvl]; 257 struct i915_page_table *alloc = NULL; 258 unsigned int idx, len; 259 int ret = 0; 260 261 GEM_BUG_ON(end > vm->total >> GEN8_PTE_SHIFT); 262 263 len = gen8_pd_range(*start, end, lvl--, &idx); 264 DBG("%s(%p):{ lvl:%d, start:%llx, end:%llx, idx:%d, len:%d, used:%d }\n", 265 __func__, vm, lvl + 1, *start, end, 266 idx, len, atomic_read(px_used(pd))); 267 GEM_BUG_ON(!len || (idx + len - 1) >> gen8_pd_shift(1)); 268 269 spin_lock(&pd->lock); 270 GEM_BUG_ON(!atomic_read(px_used(pd))); /* Must be pinned! */ 271 do { 272 struct i915_page_table *pt = pd->entry[idx]; 273 274 if (!pt) { 275 spin_unlock(&pd->lock); 276 277 DBG("%s(%p):{ lvl:%d, idx:%d } allocating new tree\n", 278 __func__, vm, lvl + 1, idx); 279 280 pt = fetch_and_zero(&alloc); 281 if (lvl) { 282 if (!pt) { 283 pt = &alloc_pd(vm)->pt; 284 if (IS_ERR(pt)) { 285 ret = PTR_ERR(pt); 286 goto out; 287 } 288 } 289 290 fill_px(pt, vm->scratch[lvl].encode); 291 } else { 292 if (!pt) { 293 pt = alloc_pt(vm); 294 if (IS_ERR(pt)) { 295 ret = PTR_ERR(pt); 296 goto out; 297 } 298 } 299 300 if (intel_vgpu_active(vm->i915) || 301 gen8_pt_count(*start, end) < I915_PDES) 302 fill_px(pt, vm->scratch[lvl].encode); 303 } 304 305 spin_lock(&pd->lock); 306 if (likely(!pd->entry[idx])) 307 set_pd_entry(pd, idx, pt); 308 else 309 alloc = pt, pt = pd->entry[idx]; 310 } 311 312 if (lvl) { 313 atomic_inc(&pt->used); 314 spin_unlock(&pd->lock); 315 316 ret = __gen8_ppgtt_alloc(vm, as_pd(pt), 317 start, end, lvl); 318 if (unlikely(ret)) { 319 if (release_pd_entry(pd, idx, pt, scratch)) 320 free_px(vm, pt); 321 goto out; 322 } 323 324 spin_lock(&pd->lock); 325 atomic_dec(&pt->used); 326 GEM_BUG_ON(!atomic_read(&pt->used)); 327 } else { 328 unsigned int count = gen8_pt_count(*start, end); 329 330 DBG("%s(%p):{ lvl:%d, start:%llx, end:%llx, idx:%d, len:%d, used:%d } inserting pte\n", 331 __func__, vm, lvl, *start, end, 332 gen8_pd_index(*start, 0), count, 333 atomic_read(&pt->used)); 334 335 atomic_add(count, &pt->used); 336 /* All other pdes may be simultaneously removed */ 337 GEM_BUG_ON(atomic_read(&pt->used) > NALLOC * I915_PDES); 338 *start += count; 339 } 340 } while (idx++, --len); 341 spin_unlock(&pd->lock); 342 out: 343 if (alloc) 344 free_px(vm, alloc); 345 return ret; 346 } 347 348 static int gen8_ppgtt_alloc(struct i915_address_space *vm, 349 u64 start, u64 length) 350 { 351 u64 from; 352 int err; 353 354 GEM_BUG_ON(!IS_ALIGNED(start, BIT_ULL(GEN8_PTE_SHIFT))); 355 GEM_BUG_ON(!IS_ALIGNED(length, BIT_ULL(GEN8_PTE_SHIFT))); 356 GEM_BUG_ON(range_overflows(start, length, vm->total)); 357 358 start >>= GEN8_PTE_SHIFT; 359 length >>= GEN8_PTE_SHIFT; 360 GEM_BUG_ON(length == 0); 361 from = start; 362 363 err = __gen8_ppgtt_alloc(vm, i915_vm_to_ppgtt(vm)->pd, 364 &start, start + length, vm->top); 365 if (unlikely(err && from != start)) 366 __gen8_ppgtt_clear(vm, i915_vm_to_ppgtt(vm)->pd, 367 from, start, vm->top); 368 369 return err; 370 } 371 372 static __always_inline u64 373 gen8_ppgtt_insert_pte(struct i915_ppgtt *ppgtt, 374 struct i915_page_directory *pdp, 375 struct sgt_dma *iter, 376 u64 idx, 377 enum i915_cache_level cache_level, 378 u32 flags) 379 { 380 struct i915_page_directory *pd; 381 const gen8_pte_t pte_encode = gen8_pte_encode(0, cache_level, flags); 382 gen8_pte_t *vaddr; 383 384 pd = i915_pd_entry(pdp, gen8_pd_index(idx, 2)); 385 vaddr = kmap_atomic_px(i915_pt_entry(pd, gen8_pd_index(idx, 1))); 386 do { 387 GEM_BUG_ON(iter->sg->length < I915_GTT_PAGE_SIZE); 388 vaddr[gen8_pd_index(idx, 0)] = pte_encode | iter->dma; 389 390 iter->dma += I915_GTT_PAGE_SIZE; 391 if (iter->dma >= iter->max) { 392 iter->sg = __sg_next(iter->sg); 393 if (!iter->sg) { 394 idx = 0; 395 break; 396 } 397 398 iter->dma = sg_dma_address(iter->sg); 399 iter->max = iter->dma + iter->sg->length; 400 } 401 402 if (gen8_pd_index(++idx, 0) == 0) { 403 if (gen8_pd_index(idx, 1) == 0) { 404 /* Limited by sg length for 3lvl */ 405 if (gen8_pd_index(idx, 2) == 0) 406 break; 407 408 pd = pdp->entry[gen8_pd_index(idx, 2)]; 409 } 410 411 kunmap_atomic(vaddr); 412 vaddr = kmap_atomic_px(i915_pt_entry(pd, gen8_pd_index(idx, 1))); 413 } 414 } while (1); 415 kunmap_atomic(vaddr); 416 417 return idx; 418 } 419 420 static void gen8_ppgtt_insert_huge(struct i915_vma *vma, 421 struct sgt_dma *iter, 422 enum i915_cache_level cache_level, 423 u32 flags) 424 { 425 const gen8_pte_t pte_encode = gen8_pte_encode(0, cache_level, flags); 426 u64 start = vma->node.start; 427 dma_addr_t rem = iter->sg->length; 428 429 GEM_BUG_ON(!i915_vm_is_4lvl(vma->vm)); 430 431 do { 432 struct i915_page_directory * const pdp = 433 gen8_pdp_for_page_address(vma->vm, start); 434 struct i915_page_directory * const pd = 435 i915_pd_entry(pdp, __gen8_pte_index(start, 2)); 436 gen8_pte_t encode = pte_encode; 437 unsigned int maybe_64K = -1; 438 unsigned int page_size; 439 gen8_pte_t *vaddr; 440 u16 index; 441 442 if (vma->page_sizes.sg & I915_GTT_PAGE_SIZE_2M && 443 IS_ALIGNED(iter->dma, I915_GTT_PAGE_SIZE_2M) && 444 rem >= I915_GTT_PAGE_SIZE_2M && 445 !__gen8_pte_index(start, 0)) { 446 index = __gen8_pte_index(start, 1); 447 encode |= GEN8_PDE_PS_2M; 448 page_size = I915_GTT_PAGE_SIZE_2M; 449 450 vaddr = kmap_atomic_px(pd); 451 } else { 452 struct i915_page_table *pt = 453 i915_pt_entry(pd, __gen8_pte_index(start, 1)); 454 455 index = __gen8_pte_index(start, 0); 456 page_size = I915_GTT_PAGE_SIZE; 457 458 if (!index && 459 vma->page_sizes.sg & I915_GTT_PAGE_SIZE_64K && 460 IS_ALIGNED(iter->dma, I915_GTT_PAGE_SIZE_64K) && 461 (IS_ALIGNED(rem, I915_GTT_PAGE_SIZE_64K) || 462 rem >= (I915_PDES - index) * I915_GTT_PAGE_SIZE)) 463 maybe_64K = __gen8_pte_index(start, 1); 464 465 vaddr = kmap_atomic_px(pt); 466 } 467 468 do { 469 GEM_BUG_ON(iter->sg->length < page_size); 470 vaddr[index++] = encode | iter->dma; 471 472 start += page_size; 473 iter->dma += page_size; 474 rem -= page_size; 475 if (iter->dma >= iter->max) { 476 iter->sg = __sg_next(iter->sg); 477 if (!iter->sg) 478 break; 479 480 rem = iter->sg->length; 481 iter->dma = sg_dma_address(iter->sg); 482 iter->max = iter->dma + rem; 483 484 if (maybe_64K != -1 && index < I915_PDES && 485 !(IS_ALIGNED(iter->dma, I915_GTT_PAGE_SIZE_64K) && 486 (IS_ALIGNED(rem, I915_GTT_PAGE_SIZE_64K) || 487 rem >= (I915_PDES - index) * I915_GTT_PAGE_SIZE))) 488 maybe_64K = -1; 489 490 if (unlikely(!IS_ALIGNED(iter->dma, page_size))) 491 break; 492 } 493 } while (rem >= page_size && index < I915_PDES); 494 495 kunmap_atomic(vaddr); 496 497 /* 498 * Is it safe to mark the 2M block as 64K? -- Either we have 499 * filled whole page-table with 64K entries, or filled part of 500 * it and have reached the end of the sg table and we have 501 * enough padding. 502 */ 503 if (maybe_64K != -1 && 504 (index == I915_PDES || 505 (i915_vm_has_scratch_64K(vma->vm) && 506 !iter->sg && IS_ALIGNED(vma->node.start + 507 vma->node.size, 508 I915_GTT_PAGE_SIZE_2M)))) { 509 vaddr = kmap_atomic_px(pd); 510 vaddr[maybe_64K] |= GEN8_PDE_IPS_64K; 511 kunmap_atomic(vaddr); 512 page_size = I915_GTT_PAGE_SIZE_64K; 513 514 /* 515 * We write all 4K page entries, even when using 64K 516 * pages. In order to verify that the HW isn't cheating 517 * by using the 4K PTE instead of the 64K PTE, we want 518 * to remove all the surplus entries. If the HW skipped 519 * the 64K PTE, it will read/write into the scratch page 520 * instead - which we detect as missing results during 521 * selftests. 522 */ 523 if (I915_SELFTEST_ONLY(vma->vm->scrub_64K)) { 524 u16 i; 525 526 encode = vma->vm->scratch[0].encode; 527 vaddr = kmap_atomic_px(i915_pt_entry(pd, maybe_64K)); 528 529 for (i = 1; i < index; i += 16) 530 memset64(vaddr + i, encode, 15); 531 532 kunmap_atomic(vaddr); 533 } 534 } 535 536 vma->page_sizes.gtt |= page_size; 537 } while (iter->sg); 538 } 539 540 static void gen8_ppgtt_insert(struct i915_address_space *vm, 541 struct i915_vma *vma, 542 enum i915_cache_level cache_level, 543 u32 flags) 544 { 545 struct i915_ppgtt * const ppgtt = i915_vm_to_ppgtt(vm); 546 struct sgt_dma iter = sgt_dma(vma); 547 548 if (vma->page_sizes.sg > I915_GTT_PAGE_SIZE) { 549 gen8_ppgtt_insert_huge(vma, &iter, cache_level, flags); 550 } else { 551 u64 idx = vma->node.start >> GEN8_PTE_SHIFT; 552 553 do { 554 struct i915_page_directory * const pdp = 555 gen8_pdp_for_page_index(vm, idx); 556 557 idx = gen8_ppgtt_insert_pte(ppgtt, pdp, &iter, idx, 558 cache_level, flags); 559 } while (idx); 560 561 vma->page_sizes.gtt = I915_GTT_PAGE_SIZE; 562 } 563 } 564 565 static int gen8_init_scratch(struct i915_address_space *vm) 566 { 567 int ret; 568 int i; 569 570 /* 571 * If everybody agrees to not to write into the scratch page, 572 * we can reuse it for all vm, keeping contexts and processes separate. 573 */ 574 if (vm->has_read_only && vm->gt->vm && !i915_is_ggtt(vm->gt->vm)) { 575 struct i915_address_space *clone = vm->gt->vm; 576 577 GEM_BUG_ON(!clone->has_read_only); 578 579 vm->scratch_order = clone->scratch_order; 580 memcpy(vm->scratch, clone->scratch, sizeof(vm->scratch)); 581 px_dma(&vm->scratch[0]) = 0; /* no xfer of ownership */ 582 return 0; 583 } 584 585 ret = setup_scratch_page(vm, __GFP_HIGHMEM); 586 if (ret) 587 return ret; 588 589 vm->scratch[0].encode = 590 gen8_pte_encode(px_dma(&vm->scratch[0]), 591 I915_CACHE_LLC, vm->has_read_only); 592 593 for (i = 1; i <= vm->top; i++) { 594 if (unlikely(setup_page_dma(vm, px_base(&vm->scratch[i])))) 595 goto free_scratch; 596 597 fill_px(&vm->scratch[i], vm->scratch[i - 1].encode); 598 vm->scratch[i].encode = 599 gen8_pde_encode(px_dma(&vm->scratch[i]), 600 I915_CACHE_LLC); 601 } 602 603 return 0; 604 605 free_scratch: 606 free_scratch(vm); 607 return -ENOMEM; 608 } 609 610 static int gen8_preallocate_top_level_pdp(struct i915_ppgtt *ppgtt) 611 { 612 struct i915_address_space *vm = &ppgtt->vm; 613 struct i915_page_directory *pd = ppgtt->pd; 614 unsigned int idx; 615 616 GEM_BUG_ON(vm->top != 2); 617 GEM_BUG_ON(gen8_pd_top_count(vm) != GEN8_3LVL_PDPES); 618 619 for (idx = 0; idx < GEN8_3LVL_PDPES; idx++) { 620 struct i915_page_directory *pde; 621 622 pde = alloc_pd(vm); 623 if (IS_ERR(pde)) 624 return PTR_ERR(pde); 625 626 fill_px(pde, vm->scratch[1].encode); 627 set_pd_entry(pd, idx, pde); 628 atomic_inc(px_used(pde)); /* keep pinned */ 629 } 630 wmb(); 631 632 return 0; 633 } 634 635 static struct i915_page_directory * 636 gen8_alloc_top_pd(struct i915_address_space *vm) 637 { 638 const unsigned int count = gen8_pd_top_count(vm); 639 struct i915_page_directory *pd; 640 641 GEM_BUG_ON(count > ARRAY_SIZE(pd->entry)); 642 643 pd = __alloc_pd(offsetof(typeof(*pd), entry[count])); 644 if (unlikely(!pd)) 645 return ERR_PTR(-ENOMEM); 646 647 if (unlikely(setup_page_dma(vm, px_base(pd)))) { 648 kfree(pd); 649 return ERR_PTR(-ENOMEM); 650 } 651 652 fill_page_dma(px_base(pd), vm->scratch[vm->top].encode, count); 653 atomic_inc(px_used(pd)); /* mark as pinned */ 654 return pd; 655 } 656 657 /* 658 * GEN8 legacy ppgtt programming is accomplished through a max 4 PDP registers 659 * with a net effect resembling a 2-level page table in normal x86 terms. Each 660 * PDP represents 1GB of memory 4 * 512 * 512 * 4096 = 4GB legacy 32b address 661 * space. 662 * 663 */ 664 struct i915_ppgtt *gen8_ppgtt_create(struct intel_gt *gt) 665 { 666 struct i915_ppgtt *ppgtt; 667 int err; 668 669 ppgtt = kzalloc(sizeof(*ppgtt), GFP_KERNEL); 670 if (!ppgtt) 671 return ERR_PTR(-ENOMEM); 672 673 ppgtt_init(ppgtt, gt); 674 ppgtt->vm.top = i915_vm_is_4lvl(&ppgtt->vm) ? 3 : 2; 675 676 /* 677 * From bdw, there is hw support for read-only pages in the PPGTT. 678 * 679 * Gen11 has HSDES#:1807136187 unresolved. Disable ro support 680 * for now. 681 * 682 * Gen12 has inherited the same read-only fault issue from gen11. 683 */ 684 ppgtt->vm.has_read_only = !IS_GEN_RANGE(gt->i915, 11, 12); 685 686 /* 687 * There are only few exceptions for gen >=6. chv and bxt. 688 * And we are not sure about the latter so play safe for now. 689 */ 690 if (IS_CHERRYVIEW(gt->i915) || IS_BROXTON(gt->i915)) 691 ppgtt->vm.pt_kmap_wc = true; 692 693 err = gen8_init_scratch(&ppgtt->vm); 694 if (err) 695 goto err_free; 696 697 ppgtt->pd = gen8_alloc_top_pd(&ppgtt->vm); 698 if (IS_ERR(ppgtt->pd)) { 699 err = PTR_ERR(ppgtt->pd); 700 goto err_free_scratch; 701 } 702 703 if (!i915_vm_is_4lvl(&ppgtt->vm)) { 704 err = gen8_preallocate_top_level_pdp(ppgtt); 705 if (err) 706 goto err_free_pd; 707 } 708 709 ppgtt->vm.bind_async_flags = I915_VMA_LOCAL_BIND; 710 ppgtt->vm.insert_entries = gen8_ppgtt_insert; 711 ppgtt->vm.allocate_va_range = gen8_ppgtt_alloc; 712 ppgtt->vm.clear_range = gen8_ppgtt_clear; 713 714 if (intel_vgpu_active(gt->i915)) 715 gen8_ppgtt_notify_vgt(ppgtt, true); 716 717 ppgtt->vm.cleanup = gen8_ppgtt_cleanup; 718 719 return ppgtt; 720 721 err_free_pd: 722 __gen8_ppgtt_cleanup(&ppgtt->vm, ppgtt->pd, 723 gen8_pd_top_count(&ppgtt->vm), ppgtt->vm.top); 724 err_free_scratch: 725 free_scratch(&ppgtt->vm); 726 err_free: 727 kfree(ppgtt); 728 return ERR_PTR(err); 729 } 730
Indexes created Mon Oct 20 15:10:11 GMT 2025