1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * (C) Copyright 2013 4 * David Feng <fenghua (at) phytium.com.cn> 5 * 6 * (C) Copyright 2016 7 * Alexander Graf <agraf (at) suse.de> 8 */ 9 10 #include <common.h> 11 #include <asm/system.h> 12 #include <asm/armv8/mmu.h> 13 14 DECLARE_GLOBAL_DATA_PTR; 15 16 #ifndef CONFIG_SYS_DCACHE_OFF 17 18 /* 19 * With 4k page granule, a virtual address is split into 4 lookup parts 20 * spanning 9 bits each: 21 * 22 * _______________________________________________ 23 * | | | | | | | 24 * | 0 | Lv0 | Lv1 | Lv2 | Lv3 | off | 25 * |_______|_______|_______|_______|_______|_______| 26 * 63-48 47-39 38-30 29-21 20-12 11-00 27 * 28 * mask page size 29 * 30 * Lv0: FF8000000000 -- 31 * Lv1: 7FC0000000 1G 32 * Lv2: 3FE00000 2M 33 * Lv3: 1FF000 4K 34 * off: FFF 35 */ 36 37 u64 get_tcr(int el, u64 *pips, u64 *pva_bits) 38 { 39 u64 max_addr = 0; 40 u64 ips, va_bits; 41 u64 tcr; 42 int i; 43 44 /* Find the largest address we need to support */ 45 for (i = 0; mem_map[i].size || mem_map[i].attrs; i++) 46 max_addr = max(max_addr, mem_map[i].virt + mem_map[i].size); 47 48 /* Calculate the maximum physical (and thus virtual) address */ 49 if (max_addr > (1ULL << 44)) { 50 ips = 5; 51 va_bits = 48; 52 } else if (max_addr > (1ULL << 42)) { 53 ips = 4; 54 va_bits = 44; 55 } else if (max_addr > (1ULL << 40)) { 56 ips = 3; 57 va_bits = 42; 58 } else if (max_addr > (1ULL << 36)) { 59 ips = 2; 60 va_bits = 40; 61 } else if (max_addr > (1ULL << 32)) { 62 ips = 1; 63 va_bits = 36; 64 } else { 65 ips = 0; 66 va_bits = 32; 67 } 68 69 if (el == 1) { 70 tcr = TCR_EL1_RSVD | (ips << 32) | TCR_EPD1_DISABLE; 71 } else if (el == 2) { 72 tcr = TCR_EL2_RSVD | (ips << 16); 73 } else { 74 tcr = TCR_EL3_RSVD | (ips << 16); 75 } 76 77 /* PTWs cacheable, inner/outer WBWA and inner shareable */ 78 tcr |= TCR_TG0_4K | TCR_SHARED_INNER | TCR_ORGN_WBWA | TCR_IRGN_WBWA; 79 tcr |= TCR_T0SZ(va_bits); 80 81 if (pips) 82 *pips = ips; 83 if (pva_bits) 84 *pva_bits = va_bits; 85 86 return tcr; 87 } 88 89 #define MAX_PTE_ENTRIES 512 90 91 static int pte_type(u64 *pte) 92 { 93 return *pte & PTE_TYPE_MASK; 94 } 95 96 /* Returns the LSB number for a PTE on level <level> */ 97 static int level2shift(int level) 98 { 99 /* Page is 12 bits wide, every level translates 9 bits */ 100 return (12 + 9 * (3 - level)); 101 } 102 103 static u64 *find_pte(u64 addr, int level) 104 { 105 int start_level = 0; 106 u64 *pte; 107 u64 idx; 108 u64 va_bits; 109 int i; 110 111 debug("addr=%llx level=%d\n", addr, level); 112 113 get_tcr(0, NULL, &va_bits); 114 if (va_bits < 39) 115 start_level = 1; 116 117 if (level < start_level) 118 return NULL; 119 120 /* Walk through all page table levels to find our PTE */ 121 pte = (u64*)gd->arch.tlb_addr; 122 for (i = start_level; i < 4; i++) { 123 idx = (addr >> level2shift(i)) & 0x1FF; 124 pte += idx; 125 debug("idx=%llx PTE %p at level %d: %llx\n", idx, pte, i, *pte); 126 127 /* Found it */ 128 if (i == level) 129 return pte; 130 /* PTE is no table (either invalid or block), can't traverse */ 131 if (pte_type(pte) != PTE_TYPE_TABLE) 132 return NULL; 133 /* Off to the next level */ 134 pte = (u64*)(*pte & 0x0000fffffffff000ULL); 135 } 136 137 /* Should never reach here */ 138 return NULL; 139 } 140 141 /* Returns and creates a new full table (512 entries) */ 142 static u64 *create_table(void) 143 { 144 u64 *new_table = (u64*)gd->arch.tlb_fillptr; 145 u64 pt_len = MAX_PTE_ENTRIES * sizeof(u64); 146 147 /* Allocate MAX_PTE_ENTRIES pte entries */ 148 gd->arch.tlb_fillptr += pt_len; 149 150 if (gd->arch.tlb_fillptr - gd->arch.tlb_addr > gd->arch.tlb_size) 151 panic("Insufficient RAM for page table: 0x%lx > 0x%lx. " 152 "Please increase the size in get_page_table_size()", 153 gd->arch.tlb_fillptr - gd->arch.tlb_addr, 154 gd->arch.tlb_size); 155 156 /* Mark all entries as invalid */ 157 memset(new_table, 0, pt_len); 158 159 return new_table; 160 } 161 162 static void set_pte_table(u64 *pte, u64 *table) 163 { 164 /* Point *pte to the new table */ 165 debug("Setting %p to addr=%p\n", pte, table); 166 *pte = PTE_TYPE_TABLE | (ulong)table; 167 } 168 169 /* Splits a block PTE into table with subpages spanning the old block */ 170 static void split_block(u64 *pte, int level) 171 { 172 u64 old_pte = *pte; 173 u64 *new_table; 174 u64 i = 0; 175 /* level describes the parent level, we need the child ones */ 176 int levelshift = level2shift(level + 1); 177 178 if (pte_type(pte) != PTE_TYPE_BLOCK) 179 panic("PTE %p (%llx) is not a block. Some driver code wants to " 180 "modify dcache settings for an range not covered in " 181 "mem_map.", pte, old_pte); 182 183 new_table = create_table(); 184 debug("Splitting pte %p (%llx) into %p\n", pte, old_pte, new_table); 185 186 for (i = 0; i < MAX_PTE_ENTRIES; i++) { 187 new_table[i] = old_pte | (i << levelshift); 188 189 /* Level 3 block PTEs have the table type */ 190 if ((level + 1) == 3) 191 new_table[i] |= PTE_TYPE_TABLE; 192 193 debug("Setting new_table[%lld] = %llx\n", i, new_table[i]); 194 } 195 196 /* Set the new table into effect */ 197 set_pte_table(pte, new_table); 198 } 199 200 /* Add one mm_region map entry to the page tables */ 201 static void add_map(struct mm_region *map) 202 { 203 u64 *pte; 204 u64 virt = map->virt; 205 u64 phys = map->phys; 206 u64 size = map->size; 207 u64 attrs = map->attrs | PTE_TYPE_BLOCK | PTE_BLOCK_AF; 208 u64 blocksize; 209 int level; 210 u64 *new_table; 211 212 while (size) { 213 pte = find_pte(virt, 0); 214 if (pte && (pte_type(pte) == PTE_TYPE_FAULT)) { 215 debug("Creating table for virt 0x%llx\n", virt); 216 new_table = create_table(); 217 set_pte_table(pte, new_table); 218 } 219 220 for (level = 1; level < 4; level++) { 221 pte = find_pte(virt, level); 222 if (!pte) 223 panic("pte not found\n"); 224 225 blocksize = 1ULL << level2shift(level); 226 debug("Checking if pte fits for virt=%llx size=%llx blocksize=%llx\n", 227 virt, size, blocksize); 228 if (size >= blocksize && !(virt & (blocksize - 1))) { 229 /* Page fits, create block PTE */ 230 debug("Setting PTE %p to block virt=%llx\n", 231 pte, virt); 232 if (level == 3) 233 *pte = phys | attrs | PTE_TYPE_PAGE; 234 else 235 *pte = phys | attrs; 236 virt += blocksize; 237 phys += blocksize; 238 size -= blocksize; 239 break; 240 } else if (pte_type(pte) == PTE_TYPE_FAULT) { 241 /* Page doesn't fit, create subpages */ 242 debug("Creating subtable for virt 0x%llx blksize=%llx\n", 243 virt, blocksize); 244 new_table = create_table(); 245 set_pte_table(pte, new_table); 246 } else if (pte_type(pte) == PTE_TYPE_BLOCK) { 247 debug("Split block into subtable for virt 0x%llx blksize=0x%llx\n", 248 virt, blocksize); 249 split_block(pte, level); 250 } 251 } 252 } 253 } 254 255 enum pte_type { 256 PTE_INVAL, 257 PTE_BLOCK, 258 PTE_LEVEL, 259 }; 260 261 /* 262 * This is a recursively called function to count the number of 263 * page tables we need to cover a particular PTE range. If you 264 * call this with level = -1 you basically get the full 48 bit 265 * coverage. 266 */ 267 static int count_required_pts(u64 addr, int level, u64 maxaddr) 268 { 269 int levelshift = level2shift(level); 270 u64 levelsize = 1ULL << levelshift; 271 u64 levelmask = levelsize - 1; 272 u64 levelend = addr + levelsize; 273 int r = 0; 274 int i; 275 enum pte_type pte_type = PTE_INVAL; 276 277 for (i = 0; mem_map[i].size || mem_map[i].attrs; i++) { 278 struct mm_region *map = &mem_map[i]; 279 u64 start = map->virt; 280 u64 end = start + map->size; 281 282 /* Check if the PTE would overlap with the map */ 283 if (max(addr, start) <= min(levelend, end)) { 284 start = max(addr, start); 285 end = min(levelend, end); 286 287 /* We need a sub-pt for this level */ 288 if ((start & levelmask) || (end & levelmask)) { 289 pte_type = PTE_LEVEL; 290 break; 291 } 292 293 /* Lv0 can not do block PTEs, so do levels here too */ 294 if (level <= 0) { 295 pte_type = PTE_LEVEL; 296 break; 297 } 298 299 /* PTE is active, but fits into a block */ 300 pte_type = PTE_BLOCK; 301 } 302 } 303 304 /* 305 * Block PTEs at this level are already covered by the parent page 306 * table, so we only need to count sub page tables. 307 */ 308 if (pte_type == PTE_LEVEL) { 309 int sublevel = level + 1; 310 u64 sublevelsize = 1ULL << level2shift(sublevel); 311 312 /* Account for the new sub page table ... */ 313 r = 1; 314 315 /* ... and for all child page tables that one might have */ 316 for (i = 0; i < MAX_PTE_ENTRIES; i++) { 317 r += count_required_pts(addr, sublevel, maxaddr); 318 addr += sublevelsize; 319 320 if (addr >= maxaddr) { 321 /* 322 * We reached the end of address space, no need 323 * to look any further. 324 */ 325 break; 326 } 327 } 328 } 329 330 return r; 331 } 332 333 /* Returns the estimated required size of all page tables */ 334 __weak u64 get_page_table_size(void) 335 { 336 u64 one_pt = MAX_PTE_ENTRIES * sizeof(u64); 337 u64 size = 0; 338 u64 va_bits; 339 int start_level = 0; 340 341 get_tcr(0, NULL, &va_bits); 342 if (va_bits < 39) 343 start_level = 1; 344 345 /* Account for all page tables we would need to cover our memory map */ 346 size = one_pt * count_required_pts(0, start_level - 1, 1ULL << va_bits); 347 348 /* 349 * We need to duplicate our page table once to have an emergency pt to 350 * resort to when splitting page tables later on 351 */ 352 size *= 2; 353 354 /* 355 * We may need to split page tables later on if dcache settings change, 356 * so reserve up to 4 (random pick) page tables for that. 357 */ 358 size += one_pt * 4; 359 360 return size; 361 } 362 363 void setup_pgtables(void) 364 { 365 int i; 366 367 if (!gd->arch.tlb_fillptr || !gd->arch.tlb_addr) 368 panic("Page table pointer not setup."); 369 370 /* 371 * Allocate the first level we're on with invalidate entries. 372 * If the starting level is 0 (va_bits >= 39), then this is our 373 * Lv0 page table, otherwise it's the entry Lv1 page table. 374 */ 375 create_table(); 376 377 /* Now add all MMU table entries one after another to the table */ 378 for (i = 0; mem_map[i].size || mem_map[i].attrs; i++) 379 add_map(&mem_map[i]); 380 } 381 382 static void setup_all_pgtables(void) 383 { 384 u64 tlb_addr = gd->arch.tlb_addr; 385 u64 tlb_size = gd->arch.tlb_size; 386 387 /* Reset the fill ptr */ 388 gd->arch.tlb_fillptr = tlb_addr; 389 390 /* Create normal system page tables */ 391 setup_pgtables(); 392 393 /* Create emergency page tables */ 394 gd->arch.tlb_size -= (uintptr_t)gd->arch.tlb_fillptr - 395 (uintptr_t)gd->arch.tlb_addr; 396 gd->arch.tlb_addr = gd->arch.tlb_fillptr; 397 setup_pgtables(); 398 gd->arch.tlb_emerg = gd->arch.tlb_addr; 399 gd->arch.tlb_addr = tlb_addr; 400 gd->arch.tlb_size = tlb_size; 401 } 402 403 /* to activate the MMU we need to set up virtual memory */ 404 __weak void mmu_setup(void) 405 { 406 int el; 407 408 /* Set up page tables only once */ 409 if (!gd->arch.tlb_fillptr) 410 setup_all_pgtables(); 411 412 el = current_el(); 413 set_ttbr_tcr_mair(el, gd->arch.tlb_addr, get_tcr(el, NULL, NULL), 414 MEMORY_ATTRIBUTES); 415 416 /* enable the mmu */ 417 set_sctlr(get_sctlr() | CR_M); 418 } 419 420 /* 421 * Performs a invalidation of the entire data cache at all levels 422 */ 423 void invalidate_dcache_all(void) 424 { 425 __asm_invalidate_dcache_all(); 426 __asm_invalidate_l3_dcache(); 427 } 428 429 /* 430 * Performs a clean & invalidation of the entire data cache at all levels. 431 * This function needs to be inline to avoid using stack. 432 * __asm_flush_l3_dcache return status of timeout 433 */ 434 inline void flush_dcache_all(void) 435 { 436 int ret; 437 438 __asm_flush_dcache_all(); 439 ret = __asm_flush_l3_dcache(); 440 if (ret) 441 debug("flushing dcache returns 0x%x\n", ret); 442 else 443 debug("flushing dcache successfully.\n"); 444 } 445 446 /* 447 * Invalidates range in all levels of D-cache/unified cache 448 */ 449 void invalidate_dcache_range(unsigned long start, unsigned long stop) 450 { 451 __asm_invalidate_dcache_range(start, stop); 452 } 453 454 /* 455 * Flush range(clean & invalidate) from all levels of D-cache/unified cache 456 */ 457 void flush_dcache_range(unsigned long start, unsigned long stop) 458 { 459 __asm_flush_dcache_range(start, stop); 460 } 461 462 void dcache_enable(void) 463 { 464 /* The data cache is not active unless the mmu is enabled */ 465 if (!(get_sctlr() & CR_M)) { 466 invalidate_dcache_all(); 467 __asm_invalidate_tlb_all(); 468 mmu_setup(); 469 } 470 471 set_sctlr(get_sctlr() | CR_C); 472 } 473 474 void dcache_disable(void) 475 { 476 uint32_t sctlr; 477 478 sctlr = get_sctlr(); 479 480 /* if cache isn't enabled no need to disable */ 481 if (!(sctlr & CR_C)) 482 return; 483 484 set_sctlr(sctlr & ~(CR_C|CR_M)); 485 486 flush_dcache_all(); 487 __asm_invalidate_tlb_all(); 488 } 489 490 int dcache_status(void) 491 { 492 return (get_sctlr() & CR_C) != 0; 493 } 494 495 u64 *__weak arch_get_page_table(void) { 496 puts("No page table offset defined\n"); 497 498 return NULL; 499 } 500 501 static bool is_aligned(u64 addr, u64 size, u64 align) 502 { 503 return !(addr & (align - 1)) && !(size & (align - 1)); 504 } 505 506 /* Use flag to indicate if attrs has more than d-cache attributes */ 507 static u64 set_one_region(u64 start, u64 size, u64 attrs, bool flag, int level) 508 { 509 int levelshift = level2shift(level); 510 u64 levelsize = 1ULL << levelshift; 511 u64 *pte = find_pte(start, level); 512 513 /* Can we can just modify the current level block PTE? */ 514 if (is_aligned(start, size, levelsize)) { 515 if (flag) { 516 *pte &= ~PMD_ATTRMASK; 517 *pte |= attrs & PMD_ATTRMASK; 518 } else { 519 *pte &= ~PMD_ATTRINDX_MASK; 520 *pte |= attrs & PMD_ATTRINDX_MASK; 521 } 522 debug("Set attrs=%llx pte=%p level=%d\n", attrs, pte, level); 523 524 return levelsize; 525 } 526 527 /* Unaligned or doesn't fit, maybe split block into table */ 528 debug("addr=%llx level=%d pte=%p (%llx)\n", start, level, pte, *pte); 529 530 /* Maybe we need to split the block into a table */ 531 if (pte_type(pte) == PTE_TYPE_BLOCK) 532 split_block(pte, level); 533 534 /* And then double-check it became a table or already is one */ 535 if (pte_type(pte) != PTE_TYPE_TABLE) 536 panic("PTE %p (%llx) for addr=%llx should be a table", 537 pte, *pte, start); 538 539 /* Roll on to the next page table level */ 540 return 0; 541 } 542 543 void mmu_set_region_dcache_behaviour(phys_addr_t start, size_t size, 544 enum dcache_option option) 545 { 546 u64 attrs = PMD_ATTRINDX(option); 547 u64 real_start = start; 548 u64 real_size = size; 549 550 debug("start=%lx size=%lx\n", (ulong)start, (ulong)size); 551 552 if (!gd->arch.tlb_emerg) 553 panic("Emergency page table not setup."); 554 555 /* 556 * We can not modify page tables that we're currently running on, 557 * so we first need to switch to the "emergency" page tables where 558 * we can safely modify our primary page tables and then switch back 559 */ 560 __asm_switch_ttbr(gd->arch.tlb_emerg); 561 562 /* 563 * Loop through the address range until we find a page granule that fits 564 * our alignment constraints, then set it to the new cache attributes 565 */ 566 while (size > 0) { 567 int level; 568 u64 r; 569 570 for (level = 1; level < 4; level++) { 571 /* Set d-cache attributes only */ 572 r = set_one_region(start, size, attrs, false, level); 573 if (r) { 574 /* PTE successfully replaced */ 575 size -= r; 576 start += r; 577 break; 578 } 579 } 580 581 } 582 583 /* We're done modifying page tables, switch back to our primary ones */ 584 __asm_switch_ttbr(gd->arch.tlb_addr); 585 586 /* 587 * Make sure there's nothing stale in dcache for a region that might 588 * have caches off now 589 */ 590 flush_dcache_range(real_start, real_start + real_size); 591 } 592 593 /* 594 * Modify MMU table for a region with updated PXN/UXN/Memory type/valid bits. 595 * The procecess is break-before-make. The target region will be marked as 596 * invalid during the process of changing. 597 */ 598 void mmu_change_region_attr(phys_addr_t addr, size_t siz, u64 attrs) 599 { 600 int level; 601 u64 r, size, start; 602 603 start = addr; 604 size = siz; 605 /* 606 * Loop through the address range until we find a page granule that fits 607 * our alignment constraints, then set it to "invalid". 608 */ 609 while (size > 0) { 610 for (level = 1; level < 4; level++) { 611 /* Set PTE to fault */ 612 r = set_one_region(start, size, PTE_TYPE_FAULT, true, 613 level); 614 if (r) { 615 /* PTE successfully invalidated */ 616 size -= r; 617 start += r; 618 break; 619 } 620 } 621 } 622 623 flush_dcache_range(gd->arch.tlb_addr, 624 gd->arch.tlb_addr + gd->arch.tlb_size); 625 __asm_invalidate_tlb_all(); 626 627 /* 628 * Loop through the address range until we find a page granule that fits 629 * our alignment constraints, then set it to the new cache attributes 630 */ 631 start = addr; 632 size = siz; 633 while (size > 0) { 634 for (level = 1; level < 4; level++) { 635 /* Set PTE to new attributes */ 636 r = set_one_region(start, size, attrs, true, level); 637 if (r) { 638 /* PTE successfully updated */ 639 size -= r; 640 start += r; 641 break; 642 } 643 } 644 } 645 flush_dcache_range(gd->arch.tlb_addr, 646 gd->arch.tlb_addr + gd->arch.tlb_size); 647 __asm_invalidate_tlb_all(); 648 } 649 650 #else /* CONFIG_SYS_DCACHE_OFF */ 651 652 /* 653 * For SPL builds, we may want to not have dcache enabled. Any real U-Boot 654 * running however really wants to have dcache and the MMU active. Check that 655 * everything is sane and give the developer a hint if it isn't. 656 */ 657 #ifndef CONFIG_SPL_BUILD 658 #error Please describe your MMU layout in CONFIG_SYS_MEM_MAP and enable dcache. 659 #endif 660 661 void invalidate_dcache_all(void) 662 { 663 } 664 665 void flush_dcache_all(void) 666 { 667 } 668 669 void dcache_enable(void) 670 { 671 } 672 673 void dcache_disable(void) 674 { 675 } 676 677 int dcache_status(void) 678 { 679 return 0; 680 } 681 682 void mmu_set_region_dcache_behaviour(phys_addr_t start, size_t size, 683 enum dcache_option option) 684 { 685 } 686 687 #endif /* CONFIG_SYS_DCACHE_OFF */ 688 689 #ifndef CONFIG_SYS_ICACHE_OFF 690 691 void icache_enable(void) 692 { 693 invalidate_icache_all(); 694 set_sctlr(get_sctlr() | CR_I); 695 } 696 697 void icache_disable(void) 698 { 699 set_sctlr(get_sctlr() & ~CR_I); 700 } 701 702 int icache_status(void) 703 { 704 return (get_sctlr() & CR_I) != 0; 705 } 706 707 void invalidate_icache_all(void) 708 { 709 __asm_invalidate_icache_all(); 710 __asm_invalidate_l3_icache(); 711 } 712 713 #else /* CONFIG_SYS_ICACHE_OFF */ 714 715 void icache_enable(void) 716 { 717 } 718 719 void icache_disable(void) 720 { 721 } 722 723 int icache_status(void) 724 { 725 return 0; 726 } 727 728 void invalidate_icache_all(void) 729 { 730 } 731 732 #endif /* CONFIG_SYS_ICACHE_OFF */ 733 734 /* 735 * Enable dCache & iCache, whether cache is actually enabled 736 * depend on CONFIG_SYS_DCACHE_OFF and CONFIG_SYS_ICACHE_OFF 737 */ 738 void __weak enable_caches(void) 739 { 740 icache_enable(); 741 dcache_enable(); 742 } 743
