1 // SPDX-License-Identifier: GPL-2.0 2 3 /* 4 * Copyright 2016-2022 HabanaLabs, Ltd. 5 * All Rights Reserved. 6 */ 7 8 #include <linux/slab.h> 9 10 #include "../habanalabs.h" 11 12 #include <trace/events/habanalabs.h> 13 14 /** 15 * hl_mmu_get_funcs() - get MMU functions structure 16 * @hdev: habanalabs device structure. 17 * @pgt_residency: page table residency. 18 * @is_dram_addr: true if we need HMMU functions 19 * 20 * @return appropriate MMU functions structure 21 */ 22 static struct hl_mmu_funcs *hl_mmu_get_funcs(struct hl_device *hdev, int pgt_residency, 23 bool is_dram_addr) 24 { 25 return &hdev->mmu_func[pgt_residency]; 26 } 27 28 bool hl_is_dram_va(struct hl_device *hdev, u64 virt_addr) 29 { 30 struct asic_fixed_properties *prop = &hdev->asic_prop; 31 32 return hl_mem_area_inside_range(virt_addr, prop->dmmu.page_size, 33 prop->dmmu.start_addr, 34 prop->dmmu.end_addr); 35 } 36 37 /** 38 * hl_mmu_init() - initialize the MMU module. 39 * @hdev: habanalabs device structure. 40 * 41 * Return: 0 for success, non-zero for failure. 42 */ 43 int hl_mmu_init(struct hl_device *hdev) 44 { 45 int rc = -EOPNOTSUPP; 46 47 if (!hdev->mmu_enable) 48 return 0; 49 50 mutex_init(&hdev->mmu_lock); 51 52 if (hdev->mmu_func[MMU_DR_PGT].init != NULL) { 53 rc = hdev->mmu_func[MMU_DR_PGT].init(hdev); 54 if (rc) 55 return rc; 56 } 57 58 if (hdev->mmu_func[MMU_HR_PGT].init != NULL) { 59 rc = hdev->mmu_func[MMU_HR_PGT].init(hdev); 60 if (rc) 61 goto fini_dr_mmu; 62 } 63 64 return 0; 65 66 fini_dr_mmu: 67 if (hdev->mmu_func[MMU_DR_PGT].fini != NULL) 68 hdev->mmu_func[MMU_DR_PGT].fini(hdev); 69 70 return rc; 71 } 72 73 /** 74 * hl_mmu_fini() - release the MMU module. 75 * @hdev: habanalabs device structure. 76 * 77 * This function does the following: 78 * - Disable MMU in H/W. 79 * - Free the pgt_infos pool. 80 * 81 * All contexts should be freed before calling this function. 82 */ 83 void hl_mmu_fini(struct hl_device *hdev) 84 { 85 if (!hdev->mmu_enable) 86 return; 87 88 if (hdev->mmu_func[MMU_DR_PGT].fini != NULL) 89 hdev->mmu_func[MMU_DR_PGT].fini(hdev); 90 91 if (hdev->mmu_func[MMU_HR_PGT].fini != NULL) 92 hdev->mmu_func[MMU_HR_PGT].fini(hdev); 93 94 mutex_destroy(&hdev->mmu_lock); 95 } 96 97 /** 98 * hl_mmu_ctx_init() - initialize a context for using the MMU module. 99 * @ctx: pointer to the context structure to initialize. 100 * 101 * Initialize a mutex to protect the concurrent mapping flow, a hash to hold all 102 * page tables hops related to this context. 103 * Return: 0 on success, non-zero otherwise. 104 */ 105 int hl_mmu_ctx_init(struct hl_ctx *ctx) 106 { 107 struct hl_device *hdev = ctx->hdev; 108 int rc = -EOPNOTSUPP; 109 110 if (!hdev->mmu_enable) 111 return 0; 112 113 if (hdev->mmu_func[MMU_DR_PGT].ctx_init != NULL) { 114 rc = hdev->mmu_func[MMU_DR_PGT].ctx_init(ctx); 115 if (rc) 116 return rc; 117 } 118 119 if (hdev->mmu_func[MMU_HR_PGT].ctx_init != NULL) { 120 rc = hdev->mmu_func[MMU_HR_PGT].ctx_init(ctx); 121 if (rc) 122 goto fini_dr_ctx; 123 } 124 125 return 0; 126 127 fini_dr_ctx: 128 if (hdev->mmu_func[MMU_DR_PGT].fini != NULL) 129 hdev->mmu_func[MMU_DR_PGT].fini(hdev); 130 131 return rc; 132 } 133 134 /* 135 * hl_mmu_ctx_fini - disable a ctx from using the mmu module 136 * 137 * @ctx: pointer to the context structure 138 * 139 * This function does the following: 140 * - Free any pgts which were not freed yet 141 * - Free the mutex 142 * - Free DRAM default page mapping hops 143 */ 144 void hl_mmu_ctx_fini(struct hl_ctx *ctx) 145 { 146 struct hl_device *hdev = ctx->hdev; 147 148 if (!hdev->mmu_enable) 149 return; 150 151 if (hdev->mmu_func[MMU_DR_PGT].ctx_fini != NULL) 152 hdev->mmu_func[MMU_DR_PGT].ctx_fini(ctx); 153 154 if (hdev->mmu_func[MMU_HR_PGT].ctx_fini != NULL) 155 hdev->mmu_func[MMU_HR_PGT].ctx_fini(ctx); 156 } 157 158 /* 159 * hl_mmu_get_real_page_size - get real page size to use in map/unmap operation 160 * 161 * @hdev: pointer to device data. 162 * @mmu_prop: MMU properties. 163 * @page_size: page size 164 * @real_page_size: set here the actual page size to use for the operation 165 * @is_dram_addr: true if DRAM address, otherwise false. 166 * 167 * @return 0 on success, otherwise non 0 error code 168 * 169 * note that this is general implementation that can fit most MMU arch. but as this is used as an 170 * MMU function: 171 * 1. it shall not be called directly- only from mmu_func structure instance 172 * 2. each MMU may modify the implementation internally 173 */ 174 int hl_mmu_get_real_page_size(struct hl_device *hdev, struct hl_mmu_properties *mmu_prop, 175 u32 page_size, u32 *real_page_size, bool is_dram_addr) 176 { 177 /* 178 * The H/W handles mapping of specific page sizes. Hence if the page 179 * size is bigger, we break it to sub-pages and map them separately. 180 */ 181 if ((page_size % mmu_prop->page_size) == 0) { 182 *real_page_size = mmu_prop->page_size; 183 return 0; 184 } 185 186 dev_err(hdev->dev, "page size of %u is not %uKB aligned, can't map\n", 187 page_size, mmu_prop->page_size >> 10); 188 189 return -EFAULT; 190 } 191 192 static struct hl_mmu_properties *hl_mmu_get_prop(struct hl_device *hdev, u32 page_size, 193 bool is_dram_addr) 194 { 195 struct asic_fixed_properties *prop = &hdev->asic_prop; 196 197 if (is_dram_addr) 198 return &prop->dmmu; 199 else if ((page_size % prop->pmmu_huge.page_size) == 0) 200 return &prop->pmmu_huge; 201 202 return &prop->pmmu; 203 } 204 205 /* 206 * hl_mmu_unmap_page - unmaps a virtual addr 207 * 208 * @ctx: pointer to the context structure 209 * @virt_addr: virt addr to map from 210 * @page_size: size of the page to unmap 211 * @flush_pte: whether to do a PCI flush 212 * 213 * This function does the following: 214 * - Check that the virt addr is mapped 215 * - Unmap the virt addr and frees pgts if possible 216 * - Returns 0 on success, -EINVAL if the given addr is not mapped 217 * 218 * Because this function changes the page tables in the device and because it 219 * changes the MMU hash, it must be protected by a lock. 220 * However, because it maps only a single page, the lock should be implemented 221 * in a higher level in order to protect the entire mapping of the memory area 222 * 223 * For optimization reasons PCI flush may be requested once after unmapping of 224 * large area. 225 */ 226 int hl_mmu_unmap_page(struct hl_ctx *ctx, u64 virt_addr, u32 page_size, bool flush_pte) 227 { 228 struct hl_device *hdev = ctx->hdev; 229 struct hl_mmu_properties *mmu_prop; 230 struct hl_mmu_funcs *mmu_funcs; 231 int i, pgt_residency, rc = 0; 232 u32 real_page_size, npages; 233 u64 real_virt_addr; 234 bool is_dram_addr; 235 236 if (!hdev->mmu_enable) 237 return 0; 238 239 is_dram_addr = hl_is_dram_va(hdev, virt_addr); 240 mmu_prop = hl_mmu_get_prop(hdev, page_size, is_dram_addr); 241 242 pgt_residency = mmu_prop->host_resident ? MMU_HR_PGT : MMU_DR_PGT; 243 mmu_funcs = hl_mmu_get_funcs(hdev, pgt_residency, is_dram_addr); 244 245 rc = hdev->asic_funcs->mmu_get_real_page_size(hdev, mmu_prop, page_size, &real_page_size, 246 is_dram_addr); 247 if (rc) 248 return rc; 249 250 npages = page_size / real_page_size; 251 real_virt_addr = virt_addr; 252 253 for (i = 0 ; i < npages ; i++) { 254 rc = mmu_funcs->unmap(ctx, real_virt_addr, is_dram_addr); 255 if (rc) 256 break; 257 258 real_virt_addr += real_page_size; 259 } 260 261 if (flush_pte) 262 mmu_funcs->flush(ctx); 263 264 if (trace_habanalabs_mmu_unmap_enabled() && !rc) 265 trace_habanalabs_mmu_unmap(hdev->dev, virt_addr, 0, page_size, flush_pte); 266 267 return rc; 268 } 269 270 /* 271 * hl_mmu_map_page - maps a virtual addr to physical addr 272 * 273 * @ctx: pointer to the context structure 274 * @virt_addr: virt addr to map from 275 * @phys_addr: phys addr to map to 276 * @page_size: physical page size 277 * @flush_pte: whether to do a PCI flush 278 * 279 * This function does the following: 280 * - Check that the virt addr is not mapped 281 * - Allocate pgts as necessary in order to map the virt addr to the phys 282 * - Returns 0 on success, -EINVAL if addr is already mapped, or -ENOMEM. 283 * 284 * Because this function changes the page tables in the device and because it 285 * changes the MMU hash, it must be protected by a lock. 286 * However, because it maps only a single page, the lock should be implemented 287 * in a higher level in order to protect the entire mapping of the memory area 288 * 289 * For optimization reasons PCI flush may be requested once after mapping of 290 * large area. 291 */ 292 int hl_mmu_map_page(struct hl_ctx *ctx, u64 virt_addr, u64 phys_addr, u32 page_size, 293 bool flush_pte) 294 { 295 int i, rc, pgt_residency, mapped_cnt = 0; 296 struct hl_device *hdev = ctx->hdev; 297 struct hl_mmu_properties *mmu_prop; 298 u64 real_virt_addr, real_phys_addr; 299 struct hl_mmu_funcs *mmu_funcs; 300 u32 real_page_size, npages; 301 bool is_dram_addr; 302 303 304 if (!hdev->mmu_enable) 305 return 0; 306 307 is_dram_addr = hl_is_dram_va(hdev, virt_addr); 308 mmu_prop = hl_mmu_get_prop(hdev, page_size, is_dram_addr); 309 310 pgt_residency = mmu_prop->host_resident ? MMU_HR_PGT : MMU_DR_PGT; 311 mmu_funcs = hl_mmu_get_funcs(hdev, pgt_residency, is_dram_addr); 312 313 rc = hdev->asic_funcs->mmu_get_real_page_size(hdev, mmu_prop, page_size, &real_page_size, 314 is_dram_addr); 315 if (rc) 316 return rc; 317 318 /* 319 * Verify that the phys and virt addresses are aligned with the 320 * MMU page size (in dram this means checking the address and MMU 321 * after scrambling) 322 */ 323 if ((is_dram_addr && 324 ((hdev->asic_funcs->scramble_addr(hdev, phys_addr) & 325 (mmu_prop->page_size - 1)) || 326 (hdev->asic_funcs->scramble_addr(hdev, virt_addr) & 327 (mmu_prop->page_size - 1)))) || 328 (!is_dram_addr && ((phys_addr & (real_page_size - 1)) || 329 (virt_addr & (real_page_size - 1))))) 330 dev_crit(hdev->dev, 331 "Mapping address 0x%llx with virtual address 0x%llx and page size of 0x%x is erroneous! Addresses must be divisible by page size", 332 phys_addr, virt_addr, real_page_size); 333 334 npages = page_size / real_page_size; 335 real_virt_addr = virt_addr; 336 real_phys_addr = phys_addr; 337 338 for (i = 0 ; i < npages ; i++) { 339 rc = mmu_funcs->map(ctx, real_virt_addr, real_phys_addr, real_page_size, 340 is_dram_addr); 341 if (rc) 342 goto err; 343 344 real_virt_addr += real_page_size; 345 real_phys_addr += real_page_size; 346 mapped_cnt++; 347 } 348 349 if (flush_pte) 350 mmu_funcs->flush(ctx); 351 352 trace_habanalabs_mmu_map(hdev->dev, virt_addr, phys_addr, page_size, flush_pte); 353 354 return 0; 355 356 err: 357 real_virt_addr = virt_addr; 358 for (i = 0 ; i < mapped_cnt ; i++) { 359 if (mmu_funcs->unmap(ctx, real_virt_addr, is_dram_addr)) 360 dev_warn_ratelimited(hdev->dev, 361 "failed to unmap va: 0x%llx\n", real_virt_addr); 362 363 real_virt_addr += real_page_size; 364 } 365 366 mmu_funcs->flush(ctx); 367 368 return rc; 369 } 370 371 /* 372 * hl_mmu_map_contiguous - implements a wrapper for hl_mmu_map_page 373 * for mapping contiguous physical memory 374 * 375 * @ctx: pointer to the context structure 376 * @virt_addr: virt addr to map from 377 * @phys_addr: phys addr to map to 378 * @size: size to map 379 * 380 */ 381 int hl_mmu_map_contiguous(struct hl_ctx *ctx, u64 virt_addr, 382 u64 phys_addr, u32 size) 383 { 384 struct hl_device *hdev = ctx->hdev; 385 struct asic_fixed_properties *prop = &hdev->asic_prop; 386 u64 curr_va, curr_pa; 387 u32 page_size; 388 bool flush_pte; 389 int rc = 0, off; 390 391 if (hl_mem_area_inside_range(virt_addr, size, 392 prop->dmmu.start_addr, prop->dmmu.end_addr)) 393 page_size = prop->dmmu.page_size; 394 else if (hl_mem_area_inside_range(virt_addr, size, 395 prop->pmmu.start_addr, prop->pmmu.end_addr)) 396 page_size = prop->pmmu.page_size; 397 else if (hl_mem_area_inside_range(virt_addr, size, 398 prop->pmmu_huge.start_addr, prop->pmmu_huge.end_addr)) 399 page_size = prop->pmmu_huge.page_size; 400 else 401 return -EINVAL; 402 403 for (off = 0 ; off < size ; off += page_size) { 404 curr_va = virt_addr + off; 405 curr_pa = phys_addr + off; 406 flush_pte = (off + page_size) >= size; 407 rc = hl_mmu_map_page(ctx, curr_va, curr_pa, page_size, 408 flush_pte); 409 if (rc) { 410 dev_err(hdev->dev, 411 "Map failed for va 0x%llx to pa 0x%llx\n", 412 curr_va, curr_pa); 413 /* last mapping failed so don't try to unmap it - reduce off by page_size */ 414 off -= page_size; 415 goto unmap; 416 } 417 } 418 419 return rc; 420 421 unmap: 422 for (; off >= 0 ; off -= page_size) { 423 curr_va = virt_addr + off; 424 flush_pte = (off - (s32) page_size) < 0; 425 if (hl_mmu_unmap_page(ctx, curr_va, page_size, flush_pte)) 426 dev_warn_ratelimited(hdev->dev, 427 "failed to unmap va 0x%llx\n", curr_va); 428 } 429 430 return rc; 431 } 432 433 /* 434 * hl_mmu_unmap_contiguous - implements a wrapper for hl_mmu_unmap_page 435 * for unmapping contiguous physical memory 436 * 437 * @ctx: pointer to the context structure 438 * @virt_addr: virt addr to unmap 439 * @size: size to unmap 440 * 441 */ 442 int hl_mmu_unmap_contiguous(struct hl_ctx *ctx, u64 virt_addr, u32 size) 443 { 444 struct hl_device *hdev = ctx->hdev; 445 struct asic_fixed_properties *prop = &hdev->asic_prop; 446 u64 curr_va; 447 u32 page_size; 448 bool flush_pte; 449 int rc = 0, off; 450 451 if (hl_mem_area_inside_range(virt_addr, size, 452 prop->dmmu.start_addr, prop->dmmu.end_addr)) 453 page_size = prop->dmmu.page_size; 454 else if (hl_mem_area_inside_range(virt_addr, size, 455 prop->pmmu.start_addr, prop->pmmu.end_addr)) 456 page_size = prop->pmmu.page_size; 457 else if (hl_mem_area_inside_range(virt_addr, size, 458 prop->pmmu_huge.start_addr, prop->pmmu_huge.end_addr)) 459 page_size = prop->pmmu_huge.page_size; 460 else 461 return -EINVAL; 462 463 for (off = 0 ; off < size ; off += page_size) { 464 curr_va = virt_addr + off; 465 flush_pte = (off + page_size) >= size; 466 rc = hl_mmu_unmap_page(ctx, curr_va, page_size, flush_pte); 467 if (rc) 468 dev_warn_ratelimited(hdev->dev, 469 "Unmap failed for va 0x%llx\n", curr_va); 470 } 471 472 return rc; 473 } 474 475 /* 476 * hl_mmu_swap_out - marks all mapping of the given ctx as swapped out 477 * 478 * @ctx: pointer to the context structure 479 * 480 */ 481 void hl_mmu_swap_out(struct hl_ctx *ctx) 482 { 483 struct hl_device *hdev = ctx->hdev; 484 485 if (!hdev->mmu_enable) 486 return; 487 488 if (hdev->mmu_func[MMU_DR_PGT].swap_out != NULL) 489 hdev->mmu_func[MMU_DR_PGT].swap_out(ctx); 490 491 if (hdev->mmu_func[MMU_HR_PGT].swap_out != NULL) 492 hdev->mmu_func[MMU_HR_PGT].swap_out(ctx); 493 } 494 495 /* 496 * hl_mmu_swap_in - marks all mapping of the given ctx as swapped in 497 * 498 * @ctx: pointer to the context structure 499 * 500 */ 501 void hl_mmu_swap_in(struct hl_ctx *ctx) 502 { 503 struct hl_device *hdev = ctx->hdev; 504 505 if (!hdev->mmu_enable) 506 return; 507 508 if (hdev->mmu_func[MMU_DR_PGT].swap_in != NULL) 509 hdev->mmu_func[MMU_DR_PGT].swap_in(ctx); 510 511 if (hdev->mmu_func[MMU_HR_PGT].swap_in != NULL) 512 hdev->mmu_func[MMU_HR_PGT].swap_in(ctx); 513 } 514 515 static void hl_mmu_pa_page_with_offset(struct hl_ctx *ctx, u64 virt_addr, 516 struct hl_mmu_hop_info *hops, 517 u64 *phys_addr) 518 { 519 struct asic_fixed_properties *prop = &ctx->hdev->asic_prop; 520 u64 offset_mask, addr_mask, hop_shift, tmp_phys_addr; 521 struct hl_mmu_properties *mmu_prop; 522 523 /* last hop holds the phys address and flags */ 524 if (hops->unscrambled_paddr) 525 tmp_phys_addr = hops->unscrambled_paddr; 526 else 527 tmp_phys_addr = hops->hop_info[hops->used_hops - 1].hop_pte_val; 528 529 if (hops->range_type == HL_VA_RANGE_TYPE_HOST_HUGE) 530 mmu_prop = &prop->pmmu_huge; 531 else if (hops->range_type == HL_VA_RANGE_TYPE_HOST) 532 mmu_prop = &prop->pmmu; 533 else /* HL_VA_RANGE_TYPE_DRAM */ 534 mmu_prop = &prop->dmmu; 535 536 if ((hops->range_type == HL_VA_RANGE_TYPE_DRAM) && 537 !is_power_of_2(prop->dram_page_size)) { 538 u64 dram_page_size, dram_base, abs_phys_addr, abs_virt_addr, 539 page_id, page_start; 540 u32 page_off; 541 542 /* 543 * Bit arithmetics cannot be used for non power of two page 544 * sizes. In addition, since bit arithmetics is not used, 545 * we cannot ignore dram base. All that shall be considered. 546 */ 547 548 dram_page_size = prop->dram_page_size; 549 dram_base = prop->dram_base_address; 550 abs_phys_addr = tmp_phys_addr - dram_base; 551 abs_virt_addr = virt_addr - dram_base; 552 page_id = DIV_ROUND_DOWN_ULL(abs_phys_addr, dram_page_size); 553 page_start = page_id * dram_page_size; 554 div_u64_rem(abs_virt_addr, dram_page_size, &page_off); 555 556 *phys_addr = page_start + page_off + dram_base; 557 } else { 558 /* 559 * find the correct hop shift field in hl_mmu_properties 560 * structure in order to determine the right masks 561 * for the page offset. 562 */ 563 hop_shift = mmu_prop->hop_shifts[hops->used_hops - 1]; 564 offset_mask = (1ull << hop_shift) - 1; 565 addr_mask = ~(offset_mask); 566 *phys_addr = (tmp_phys_addr & addr_mask) | 567 (virt_addr & offset_mask); 568 } 569 } 570 571 int hl_mmu_va_to_pa(struct hl_ctx *ctx, u64 virt_addr, u64 *phys_addr) 572 { 573 struct hl_mmu_hop_info hops; 574 int rc; 575 576 memset(&hops, 0, sizeof(hops)); 577 578 rc = hl_mmu_get_tlb_info(ctx, virt_addr, &hops); 579 if (rc) 580 return rc; 581 582 hl_mmu_pa_page_with_offset(ctx, virt_addr, &hops, phys_addr); 583 584 return 0; 585 } 586 587 int hl_mmu_get_tlb_info(struct hl_ctx *ctx, u64 virt_addr, 588 struct hl_mmu_hop_info *hops) 589 { 590 struct hl_device *hdev = ctx->hdev; 591 struct asic_fixed_properties *prop; 592 struct hl_mmu_properties *mmu_prop; 593 struct hl_mmu_funcs *mmu_funcs; 594 int pgt_residency, rc; 595 bool is_dram_addr; 596 597 if (!hdev->mmu_enable) 598 return -EOPNOTSUPP; 599 600 prop = &hdev->asic_prop; 601 hops->scrambled_vaddr = virt_addr; /* assume no scrambling */ 602 603 is_dram_addr = hl_mem_area_inside_range(virt_addr, prop->dmmu.page_size, 604 prop->dmmu.start_addr, 605 prop->dmmu.end_addr); 606 607 /* host-residency is the same in PMMU and PMMU huge, no need to distinguish here */ 608 mmu_prop = is_dram_addr ? &prop->dmmu : &prop->pmmu; 609 pgt_residency = mmu_prop->host_resident ? MMU_HR_PGT : MMU_DR_PGT; 610 mmu_funcs = hl_mmu_get_funcs(hdev, pgt_residency, is_dram_addr); 611 612 mutex_lock(&hdev->mmu_lock); 613 rc = mmu_funcs->get_tlb_info(ctx, virt_addr, hops); 614 mutex_unlock(&hdev->mmu_lock); 615 616 if (rc) 617 return rc; 618 619 /* add page offset to physical address */ 620 if (hops->unscrambled_paddr) 621 hl_mmu_pa_page_with_offset(ctx, virt_addr, hops, &hops->unscrambled_paddr); 622 623 return 0; 624 } 625 626 int hl_mmu_if_set_funcs(struct hl_device *hdev) 627 { 628 if (!hdev->mmu_enable) 629 return 0; 630 631 switch (hdev->asic_type) { 632 case ASIC_GOYA: 633 case ASIC_GAUDI: 634 case ASIC_GAUDI_SEC: 635 hl_mmu_v1_set_funcs(hdev, &hdev->mmu_func[MMU_DR_PGT]); 636 break; 637 case ASIC_GAUDI2: 638 case ASIC_GAUDI2B: 639 /* MMUs in Gaudi2 are always host resident */ 640 hl_mmu_v2_hr_set_funcs(hdev, &hdev->mmu_func[MMU_HR_PGT]); 641 break; 642 default: 643 dev_err(hdev->dev, "Unrecognized ASIC type %d\n", 644 hdev->asic_type); 645 return -EOPNOTSUPP; 646 } 647 648 return 0; 649 } 650 651 /** 652 * hl_mmu_scramble_addr() - The generic mmu address scrambling routine. 653 * @hdev: pointer to device data. 654 * @addr: The address to scramble. 655 * 656 * Return: The scrambled address. 657 */ 658 u64 hl_mmu_scramble_addr(struct hl_device *hdev, u64 addr) 659 { 660 return addr; 661 } 662 663 /** 664 * hl_mmu_descramble_addr() - The generic mmu address descrambling 665 * routine. 666 * @hdev: pointer to device data. 667 * @addr: The address to descramble. 668 * 669 * Return: The un-scrambled address. 670 */ 671 u64 hl_mmu_descramble_addr(struct hl_device *hdev, u64 addr) 672 { 673 return addr; 674 } 675 676 int hl_mmu_invalidate_cache(struct hl_device *hdev, bool is_hard, u32 flags) 677 { 678 int rc; 679 680 rc = hdev->asic_funcs->mmu_invalidate_cache(hdev, is_hard, flags); 681 if (rc) 682 dev_err_ratelimited(hdev->dev, "MMU cache invalidation failed\n"); 683 684 return rc; 685 } 686 687 int hl_mmu_invalidate_cache_range(struct hl_device *hdev, bool is_hard, 688 u32 flags, u32 asid, u64 va, u64 size) 689 { 690 int rc; 691 692 rc = hdev->asic_funcs->mmu_invalidate_cache_range(hdev, is_hard, flags, 693 asid, va, size); 694 if (rc) 695 dev_err_ratelimited(hdev->dev, "MMU cache range invalidation failed\n"); 696 697 return rc; 698 } 699 700 static void hl_mmu_prefetch_work_function(struct work_struct *work) 701 { 702 struct hl_prefetch_work *pfw = container_of(work, struct hl_prefetch_work, prefetch_work); 703 struct hl_ctx *ctx = pfw->ctx; 704 struct hl_device *hdev = ctx->hdev; 705 706 if (!hl_device_operational(hdev, NULL)) 707 goto put_ctx; 708 709 mutex_lock(&hdev->mmu_lock); 710 711 hdev->asic_funcs->mmu_prefetch_cache_range(ctx, pfw->flags, pfw->asid, pfw->va, pfw->size); 712 713 mutex_unlock(&hdev->mmu_lock); 714 715 put_ctx: 716 /* 717 * context was taken in the common mmu prefetch function- see comment there about 718 * context handling. 719 */ 720 hl_ctx_put(ctx); 721 kfree(pfw); 722 } 723 724 int hl_mmu_prefetch_cache_range(struct hl_ctx *ctx, u32 flags, u32 asid, u64 va, u64 size) 725 { 726 struct hl_prefetch_work *handle_prefetch_work; 727 728 handle_prefetch_work = kmalloc(sizeof(*handle_prefetch_work), GFP_KERNEL); 729 if (!handle_prefetch_work) 730 return -ENOMEM; 731 732 INIT_WORK(&handle_prefetch_work->prefetch_work, hl_mmu_prefetch_work_function); 733 handle_prefetch_work->ctx = ctx; 734 handle_prefetch_work->va = va; 735 handle_prefetch_work->size = size; 736 handle_prefetch_work->flags = flags; 737 handle_prefetch_work->asid = asid; 738 739 /* 740 * as actual prefetch is done in a WQ we must get the context (and put it 741 * at the end of the work function) 742 */ 743 hl_ctx_get(ctx); 744 queue_work(ctx->hdev->prefetch_wq, &handle_prefetch_work->prefetch_work); 745 746 return 0; 747 } 748 749 u64 hl_mmu_get_next_hop_addr(struct hl_ctx *ctx, u64 curr_pte) 750 { 751 return (curr_pte & PAGE_PRESENT_MASK) ? (curr_pte & HOP_PHYS_ADDR_MASK) : ULLONG_MAX; 752 } 753 754 /** 755 * hl_mmu_get_hop_pte_phys_addr() - extract PTE address from HOP 756 * @ctx: pointer to the context structure to initialize. 757 * @mmu_prop: MMU properties. 758 * @hop_idx: HOP index. 759 * @hop_addr: HOP address. 760 * @virt_addr: virtual address fro the translation. 761 * 762 * @return the matching PTE value on success, otherwise U64_MAX. 763 */ 764 u64 hl_mmu_get_hop_pte_phys_addr(struct hl_ctx *ctx, struct hl_mmu_properties *mmu_prop, 765 u8 hop_idx, u64 hop_addr, u64 virt_addr) 766 { 767 u64 mask, shift; 768 769 if (hop_idx >= mmu_prop->num_hops) { 770 dev_err_ratelimited(ctx->hdev->dev, "Invalid hop index %d\n", hop_idx); 771 return U64_MAX; 772 } 773 774 shift = mmu_prop->hop_shifts[hop_idx]; 775 mask = mmu_prop->hop_masks[hop_idx]; 776 777 return hop_addr + ctx->hdev->asic_prop.mmu_pte_size * ((virt_addr & mask) >> shift); 778 } 779 780 static void mmu_dma_mem_free_from_chunk(struct gen_pool *pool, 781 struct gen_pool_chunk *chunk, 782 void *data) 783 { 784 struct hl_device *hdev = data; 785 786 hl_asic_dma_free_coherent(hdev, (chunk->end_addr - chunk->start_addr) + 1, 787 (void *)chunk->start_addr, chunk->phys_addr); 788 } 789 790 void hl_mmu_hr_flush(struct hl_ctx *ctx) 791 { 792 /* a flush operation requires memory barrier */ 793 mb(); 794 } 795 796 /** 797 * hl_mmu_hr_pool_destroy() - destroy genpool 798 * @hdev: habanalabs device structure. 799 * @hr_priv: MMU HR private data. 800 * @hop_table_size: HOP table size. 801 * 802 * This function does the following: 803 * - free entries allocated for shadow HOP0 804 * - free pool chunks 805 * - free pool 806 */ 807 static void hl_mmu_hr_pool_destroy(struct hl_device *hdev, struct hl_mmu_hr_priv *hr_priv, 808 u32 hop_table_size) 809 { 810 struct asic_fixed_properties *prop = &hdev->asic_prop; 811 struct gen_pool **pool = &hr_priv->mmu_pgt_pool; 812 struct pgt_info *hop0_pgt; 813 int asid; 814 815 if (ZERO_OR_NULL_PTR(*pool)) 816 return; 817 818 /* Free the Fixed allocation of HOPs0 */ 819 if (hr_priv->mmu_asid_hop0) { 820 for (asid = 0 ; asid < prop->max_asid ; asid++) { 821 hop0_pgt = &hr_priv->mmu_asid_hop0[asid]; 822 if (ZERO_OR_NULL_PTR(hop0_pgt->virt_addr)) 823 continue; 824 825 gen_pool_free(*pool, (uintptr_t) hop0_pgt->virt_addr, hop_table_size); 826 } 827 } 828 829 gen_pool_for_each_chunk(*pool, mmu_dma_mem_free_from_chunk, hdev); 830 gen_pool_destroy(*pool); 831 832 /* Make sure that if we arrive here again without init was called we 833 * won't cause kernel panic. This can happen for example if we fail 834 * during hard reset code at certain points 835 */ 836 *pool = NULL; 837 } 838 839 /** 840 * hl_mmu_hr_init() - initialize the MMU module. 841 * @hdev: habanalabs device structure. 842 * @hr_priv: MMU HR private data. 843 * @hop_table_size: HOP table size. 844 * @pgt_size: memory size allocated for the page table 845 * 846 * @return 0 on success otherwise non-zero error code 847 * 848 * This function does the following: 849 * - Create a pool of pages for pgt_infos. 850 * - Create a shadow table for pgt 851 */ 852 int hl_mmu_hr_init(struct hl_device *hdev, struct hl_mmu_hr_priv *hr_priv, u32 hop_table_size, 853 u64 pgt_size) 854 { 855 struct asic_fixed_properties *prop = &hdev->asic_prop; 856 size_t pool_chunk_size = SZ_4M; 857 struct pgt_info *hop0_pgt; 858 dma_addr_t dma_addr; 859 u64 virt_addr; 860 int i, rc; 861 862 /* 863 * we set alloc size as PAGE_SIZE (sine dma_alloc_coherent allocation order/size is 864 * PAGE_SHIFT/PAGE_SIZE) in order to be able to control the allocations alignment. 865 * This way we can call "DMA alloc align" according to dma_alloc granularity and supply 866 * allocations with higher-order alignment restrictions 867 */ 868 hr_priv->mmu_pgt_pool = gen_pool_create(PAGE_SHIFT, -1); 869 if (ZERO_OR_NULL_PTR(hr_priv->mmu_pgt_pool)) { 870 dev_err(hdev->dev, "Failed to create hr page pool\n"); 871 return -ENOMEM; 872 } 873 874 hr_priv->mmu_asid_hop0 = kvcalloc(prop->max_asid, sizeof(struct pgt_info), GFP_KERNEL); 875 if (ZERO_OR_NULL_PTR(hr_priv->mmu_asid_hop0)) { 876 dev_err(hdev->dev, "Failed to allocate hr-mmu hop0 table\n"); 877 rc = -ENOMEM; 878 goto destroy_mmu_pgt_pool; 879 } 880 881 for (i = 0 ; i < pgt_size ; i += pool_chunk_size) { 882 virt_addr = (uintptr_t) hl_asic_dma_alloc_coherent(hdev, pool_chunk_size, 883 &dma_addr, 884 GFP_KERNEL | __GFP_ZERO); 885 if (ZERO_OR_NULL_PTR(virt_addr)) { 886 dev_err(hdev->dev, 887 "Failed to allocate memory for host-resident page pool\n"); 888 rc = -ENOMEM; 889 goto destroy_mmu_pgt_pool; 890 } 891 892 rc = gen_pool_add_virt(hr_priv->mmu_pgt_pool, virt_addr, (phys_addr_t) dma_addr, 893 pool_chunk_size, -1); 894 if (rc) { 895 dev_err(hdev->dev, "Failed to fill host-resident page pool\n"); 896 goto destroy_mmu_pgt_pool; 897 } 898 } 899 900 for (i = 0 ; i < prop->max_asid ; i++) { 901 hop0_pgt = &hr_priv->mmu_asid_hop0[i]; 902 hop0_pgt->virt_addr = (uintptr_t) 903 gen_pool_dma_zalloc_align(hr_priv->mmu_pgt_pool, 904 hop_table_size, 905 (dma_addr_t *) &hop0_pgt->phys_addr, 906 hop_table_size); 907 if (!hop0_pgt->virt_addr) { 908 dev_err(hdev->dev, "Failed to allocate HOP from pgt pool\n"); 909 rc = -ENOMEM; 910 goto destroy_mmu_pgt_pool; 911 } 912 } 913 914 /* MMU H/W init will be done in device hw_init() */ 915 916 return 0; 917 918 destroy_mmu_pgt_pool: 919 hl_mmu_hr_pool_destroy(hdev, hr_priv, hop_table_size); 920 if (!ZERO_OR_NULL_PTR(hr_priv->mmu_asid_hop0)) 921 kvfree(hr_priv->mmu_asid_hop0); 922 923 return rc; 924 } 925 926 /** 927 * hl_mmu_hr_fini() - release the MMU module. 928 * @hdev: habanalabs device structure. 929 * @hr_priv: MMU host resident private info. 930 * @hop_table_size: HOP table size 931 * 932 * This function does the following: 933 * - Disable MMU in H/W. 934 * - Free the pgt_infos pool. 935 * 936 * All contexts should be freed before calling this function. 937 */ 938 void hl_mmu_hr_fini(struct hl_device *hdev, struct hl_mmu_hr_priv *hr_priv, u32 hop_table_size) 939 { 940 /* MMU H/W fini was already done in device hw_fini() */ 941 942 hl_mmu_hr_pool_destroy(hdev, hr_priv, hop_table_size); 943 944 if (!ZERO_OR_NULL_PTR(hr_priv->mmu_asid_hop0)) { 945 kvfree(hr_priv->mmu_asid_hop0); 946 947 /* Make sure that if we arrive here again without init was 948 * called we won't cause kernel panic. This can happen for 949 * example if we fail during hard reset code at certain points 950 */ 951 hr_priv->mmu_asid_hop0 = NULL; 952 } 953 } 954 955 /** 956 * hl_mmu_hr_free_hop_remove_pgt() - free HOP and remove PGT from hash 957 * @pgt_info: page table info structure. 958 * @hr_priv: MMU HR private data. 959 * @hop_table_size: HOP table size. 960 */ 961 void hl_mmu_hr_free_hop_remove_pgt(struct pgt_info *pgt_info, struct hl_mmu_hr_priv *hr_priv, 962 u32 hop_table_size) 963 { 964 gen_pool_free(hr_priv->mmu_pgt_pool, pgt_info->virt_addr, hop_table_size); 965 hash_del(&pgt_info->node); 966 kfree(pgt_info); 967 } 968 969 /** 970 * hl_mmu_hr_pte_phys_to_virt() - translate PTE phys addr to virt addr 971 * @ctx: pointer to the context structure 972 * @pgt: pgt_info for the HOP hosting the PTE 973 * @phys_pte_addr: phys address of the PTE 974 * @hop_table_size: HOP table size 975 * 976 * @return PTE virtual address 977 * 978 * The function use the pgt_info to get HOP base virt addr and obtain the PTE's virt addr 979 * by adding the PTE offset. 980 */ 981 u64 hl_mmu_hr_pte_phys_to_virt(struct hl_ctx *ctx, struct pgt_info *pgt, 982 u64 phys_pte_addr, u32 hop_table_size) 983 { 984 u64 page_mask = (hop_table_size - 1); 985 u64 pte_offset = phys_pte_addr & page_mask; 986 987 return pgt->virt_addr + pte_offset; 988 } 989 990 /** 991 * hl_mmu_hr_write_pte() - write HR PTE 992 * @ctx: pointer to the context structure 993 * @pgt_info: HOP's page table info structure 994 * @phys_pte_addr: phys PTE address 995 * @val: raw PTE data 996 * @hop_table_size: HOP table size 997 */ 998 void hl_mmu_hr_write_pte(struct hl_ctx *ctx, struct pgt_info *pgt_info, u64 phys_pte_addr, 999 u64 val, u32 hop_table_size) 1000 { 1001 /* 1002 * The value to write is the phys address of the next hop + 1003 * flags at the 12 LSBs. 1004 */ 1005 u64 virt_addr = hl_mmu_hr_pte_phys_to_virt(ctx, pgt_info, phys_pte_addr, hop_table_size); 1006 1007 *((u64 *) (uintptr_t) virt_addr) = val; 1008 } 1009 1010 /** 1011 * hl_mmu_hr_clear_pte() - clear HR PTE 1012 * @ctx: pointer to the context structure 1013 * @pgt_info: HOP's page table info structure 1014 * @phys_pte_addr: phys PTE address 1015 * @hop_table_size: HOP table size 1016 */ 1017 void hl_mmu_hr_clear_pte(struct hl_ctx *ctx, struct pgt_info *pgt_info, u64 phys_pte_addr, 1018 u32 hop_table_size) 1019 { 1020 /* no need to transform the value to physical address */ 1021 hl_mmu_hr_write_pte(ctx, pgt_info, phys_pte_addr, 0, hop_table_size); 1022 } 1023 1024 /** 1025 * hl_mmu_hr_put_pte() - put HR PTE and remove it if necessary (no more PTEs) 1026 * @ctx: pointer to the context structure 1027 * @pgt_info: HOP's page table info structure 1028 * @hr_priv: HR MMU private info 1029 * @hop_table_size: HOP table size 1030 * 1031 * @return number of PTEs still in the HOP 1032 */ 1033 int hl_mmu_hr_put_pte(struct hl_ctx *ctx, struct pgt_info *pgt_info, 1034 struct hl_mmu_hr_priv *hr_priv, 1035 u32 hop_table_size) 1036 { 1037 int num_of_ptes_left; 1038 1039 pgt_info->num_of_ptes--; 1040 1041 /* 1042 * Need to save the number of ptes left because free_hop might free 1043 * the pgt_info 1044 */ 1045 num_of_ptes_left = pgt_info->num_of_ptes; 1046 if (!num_of_ptes_left) 1047 hl_mmu_hr_free_hop_remove_pgt(pgt_info, hr_priv, hop_table_size); 1048 1049 return num_of_ptes_left; 1050 } 1051 1052 /** 1053 * hl_mmu_hr_get_pte() - increase PGT PTE count 1054 * @ctx: pointer to the context structure 1055 * @hr_func: host resident functions 1056 * @phys_hop_addr: HOP phys address 1057 */ 1058 void hl_mmu_hr_get_pte(struct hl_ctx *ctx, struct hl_hr_mmu_funcs *hr_func, u64 phys_hop_addr) 1059 { 1060 hr_func->get_pgt_info(ctx, phys_hop_addr)->num_of_ptes++; 1061 } 1062 1063 /** 1064 * hl_mmu_hr_get_next_hop_pgt_info() - get pgt_info structure for the next HOP 1065 * @ctx: pointer to the context structure. 1066 * @hr_func: host resident functions. 1067 * @curr_pte: current PTE value. 1068 * 1069 * @return pgt_info structure on success, otherwise NULL. 1070 */ 1071 struct pgt_info *hl_mmu_hr_get_next_hop_pgt_info(struct hl_ctx *ctx, 1072 struct hl_hr_mmu_funcs *hr_func, 1073 u64 curr_pte) 1074 { 1075 u64 next_hop_phys_addr = hl_mmu_get_next_hop_addr(ctx, curr_pte); 1076 1077 if (next_hop_phys_addr == ULLONG_MAX) 1078 return NULL; 1079 1080 return hr_func->get_pgt_info(ctx, next_hop_phys_addr); 1081 } 1082 1083 /** 1084 * hl_mmu_hr_alloc_hop() - allocate HOP 1085 * @ctx: pointer to the context structure. 1086 * @hr_priv: host resident private info structure. 1087 * @hr_func: host resident functions. 1088 * @mmu_prop: MMU properties. 1089 * 1090 * @return pgt_info structure associated with the allocated HOP on success, otherwise NULL. 1091 */ 1092 struct pgt_info *hl_mmu_hr_alloc_hop(struct hl_ctx *ctx, struct hl_mmu_hr_priv *hr_priv, 1093 struct hl_hr_mmu_funcs *hr_func, 1094 struct hl_mmu_properties *mmu_prop) 1095 { 1096 struct hl_device *hdev = ctx->hdev; 1097 struct pgt_info *pgt_info; 1098 dma_addr_t phys_addr; 1099 void *virt_addr; 1100 int i, retry = 1; 1101 1102 pgt_info = kmalloc(sizeof(*pgt_info), GFP_KERNEL); 1103 if (!pgt_info) 1104 return NULL; 1105 1106 for (i = 0; i <= retry; i++) { 1107 virt_addr = gen_pool_dma_zalloc_align(hr_priv->mmu_pgt_pool, 1108 mmu_prop->hop_table_size, 1109 &phys_addr, 1110 mmu_prop->hop_table_size); 1111 if (virt_addr) 1112 break; 1113 1114 /* No memory in pool - get some and try again */ 1115 virt_addr = hl_asic_dma_alloc_coherent(hdev, SZ_2M, &phys_addr, 1116 GFP_KERNEL | __GFP_ZERO); 1117 if (ZERO_OR_NULL_PTR(virt_addr)) 1118 break; 1119 1120 if (gen_pool_add_virt(hr_priv->mmu_pgt_pool, (unsigned long)virt_addr, 1121 phys_addr, SZ_2M, -1)) { 1122 hl_asic_dma_free_coherent(hdev, SZ_2M, virt_addr, phys_addr); 1123 virt_addr = NULL; 1124 break; 1125 } 1126 } 1127 1128 if (ZERO_OR_NULL_PTR(virt_addr)) { 1129 dev_err(hdev->dev, "failed to allocate page\n"); 1130 goto pool_alloc_err; 1131 } 1132 1133 pgt_info->phys_addr = phys_addr; 1134 pgt_info->shadow_addr = (unsigned long) NULL; 1135 pgt_info->virt_addr = (unsigned long)virt_addr; 1136 pgt_info->ctx = ctx; 1137 pgt_info->num_of_ptes = 0; 1138 hr_func->add_pgt_info(ctx, pgt_info, phys_addr); 1139 1140 return pgt_info; 1141 1142 pool_alloc_err: 1143 kfree(pgt_info); 1144 1145 return NULL; 1146 } 1147 1148 /** 1149 * hl_mmu_hr_get_alloc_next_hop() - get the next HOP, allocate it if it does not exist 1150 * @ctx: pointer to the context structure. 1151 * @hr_priv: host resident private info structure. 1152 * @hr_func: host resident functions. 1153 * @mmu_prop: MMU properties. 1154 * @curr_pte: current PTE value. 1155 * @is_new_hop: set to true if HOP is new (caller responsibility to set it to false). 1156 * 1157 * @return pgt_info structure associated with the allocated HOP on success, otherwise NULL. 1158 */ 1159 struct pgt_info *hl_mmu_hr_get_alloc_next_hop(struct hl_ctx *ctx, 1160 struct hl_mmu_hr_priv *hr_priv, 1161 struct hl_hr_mmu_funcs *hr_func, 1162 struct hl_mmu_properties *mmu_prop, 1163 u64 curr_pte, bool *is_new_hop) 1164 { 1165 u64 hop_addr = hl_mmu_get_next_hop_addr(ctx, curr_pte); 1166 1167 if (hop_addr != ULLONG_MAX) 1168 return hr_func->get_pgt_info(ctx, hop_addr); 1169 1170 *is_new_hop = true; 1171 return hl_mmu_hr_alloc_hop(ctx, hr_priv, hr_func, mmu_prop); 1172 } 1173 1174 /** 1175 * hl_mmu_hr_get_tlb_info() - get the TLB info (info for a specific mapping) 1176 * @ctx: pointer to the context structure. 1177 * @virt_addr: the virt address for which to get info. 1178 * @hops: HOPs info structure. 1179 * @hr_func: host resident functions. 1180 * 1181 * @return 0 on success, otherwise non 0 error code.. 1182 */ 1183 int hl_mmu_hr_get_tlb_info(struct hl_ctx *ctx, u64 virt_addr, struct hl_mmu_hop_info *hops, 1184 struct hl_hr_mmu_funcs *hr_func) 1185 { 1186 /* using 6 HOPs as this is the maximum number of HOPs */ 1187 struct pgt_info *hops_pgt_info[MMU_ARCH_6_HOPS] = { NULL }; 1188 struct hl_device *hdev = ctx->hdev; 1189 struct hl_mmu_properties *mmu_prop; 1190 int rc, i, used_hops; 1191 bool is_huge; 1192 1193 rc = hr_func->get_tlb_mapping_params(hdev, &mmu_prop, hops, virt_addr, &is_huge); 1194 if (rc) 1195 return rc; 1196 1197 used_hops = mmu_prop->num_hops; 1198 1199 /* huge pages use one less hop */ 1200 if (is_huge) 1201 used_hops--; 1202 1203 hops->scrambled_vaddr = hdev->asic_funcs->scramble_addr(hdev, virt_addr); 1204 1205 for (i = 0 ; i < used_hops ; i++) { 1206 if (i == 0) 1207 hops_pgt_info[i] = hr_func->get_hop0_pgt_info(ctx); 1208 else 1209 hops_pgt_info[i] = hl_mmu_hr_get_next_hop_pgt_info(ctx, hr_func, 1210 hops->hop_info[i - 1].hop_pte_val); 1211 1212 if (!hops_pgt_info[i]) 1213 return -EFAULT; 1214 1215 hops->hop_info[i].hop_addr = hops_pgt_info[i]->phys_addr; 1216 hops->hop_info[i].hop_pte_addr = 1217 hl_mmu_get_hop_pte_phys_addr(ctx, mmu_prop, i, 1218 hops->hop_info[i].hop_addr, 1219 hops->scrambled_vaddr); 1220 hops->hop_info[i].hop_pte_val = *(u64 *) (uintptr_t) 1221 hl_mmu_hr_pte_phys_to_virt(ctx, hops_pgt_info[i], 1222 hops->hop_info[i].hop_pte_addr, 1223 mmu_prop->hop_table_size); 1224 1225 if (!(hops->hop_info[i].hop_pte_val & PAGE_PRESENT_MASK)) 1226 return -EFAULT; 1227 1228 if (hops->hop_info[i].hop_pte_val & mmu_prop->last_mask) 1229 break; 1230 } 1231 1232 /* if passed over all hops then no last hop was found */ 1233 if (i == mmu_prop->num_hops) 1234 return -EFAULT; 1235 1236 if (hops->scrambled_vaddr != virt_addr) 1237 hops->unscrambled_paddr = hdev->asic_funcs->descramble_addr 1238 (hdev, hops->hop_info[i].hop_pte_val); 1239 else 1240 hops->unscrambled_paddr = hops->hop_info[i].hop_pte_val; 1241 1242 hops->used_hops = i + 1; 1243 1244 return 0; 1245 } 1246 1247