1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Apple DART (Device Address Resolution Table) IOMMU driver 4 * 5 * Copyright (C) 2021 The Asahi Linux Contributors 6 * 7 * Based on arm/arm-smmu/arm-ssmu.c and arm/arm-smmu-v3/arm-smmu-v3.c 8 * Copyright (C) 2013 ARM Limited 9 * Copyright (C) 2015 ARM Limited 10 * and on exynos-iommu.c 11 * Copyright (c) 2011,2016 Samsung Electronics Co., Ltd. 12 */ 13 14 #include <linux/atomic.h> 15 #include <linux/bitfield.h> 16 #include <linux/clk.h> 17 #include <linux/dev_printk.h> 18 #include <linux/dma-iommu.h> 19 #include <linux/dma-mapping.h> 20 #include <linux/err.h> 21 #include <linux/interrupt.h> 22 #include <linux/io-pgtable.h> 23 #include <linux/iommu.h> 24 #include <linux/iopoll.h> 25 #include <linux/module.h> 26 #include <linux/of.h> 27 #include <linux/of_address.h> 28 #include <linux/of_iommu.h> 29 #include <linux/of_platform.h> 30 #include <linux/pci.h> 31 #include <linux/platform_device.h> 32 #include <linux/slab.h> 33 #include <linux/swab.h> 34 #include <linux/types.h> 35 36 #define DART_MAX_STREAMS 16 37 #define DART_MAX_TTBR 4 38 #define MAX_DARTS_PER_DEVICE 2 39 40 #define DART_STREAM_ALL 0xffff 41 42 #define DART_PARAMS1 0x00 43 #define DART_PARAMS_PAGE_SHIFT GENMASK(27, 24) 44 45 #define DART_PARAMS2 0x04 46 #define DART_PARAMS_BYPASS_SUPPORT BIT(0) 47 48 #define DART_STREAM_COMMAND 0x20 49 #define DART_STREAM_COMMAND_BUSY BIT(2) 50 #define DART_STREAM_COMMAND_INVALIDATE BIT(20) 51 52 #define DART_STREAM_SELECT 0x34 53 54 #define DART_ERROR 0x40 55 #define DART_ERROR_STREAM GENMASK(27, 24) 56 #define DART_ERROR_CODE GENMASK(11, 0) 57 #define DART_ERROR_FLAG BIT(31) 58 59 #define DART_ERROR_READ_FAULT BIT(4) 60 #define DART_ERROR_WRITE_FAULT BIT(3) 61 #define DART_ERROR_NO_PTE BIT(2) 62 #define DART_ERROR_NO_PMD BIT(1) 63 #define DART_ERROR_NO_TTBR BIT(0) 64 65 #define DART_CONFIG 0x60 66 #define DART_CONFIG_LOCK BIT(15) 67 68 #define DART_STREAM_COMMAND_BUSY_TIMEOUT 100 69 70 #define DART_ERROR_ADDR_HI 0x54 71 #define DART_ERROR_ADDR_LO 0x50 72 73 #define DART_TCR(sid) (0x100 + 4 * (sid)) 74 #define DART_TCR_TRANSLATE_ENABLE BIT(7) 75 #define DART_TCR_BYPASS0_ENABLE BIT(8) 76 #define DART_TCR_BYPASS1_ENABLE BIT(12) 77 78 #define DART_TTBR(sid, idx) (0x200 + 16 * (sid) + 4 * (idx)) 79 #define DART_TTBR_VALID BIT(31) 80 #define DART_TTBR_SHIFT 12 81 82 /* 83 * Private structure associated with each DART device. 84 * 85 * @dev: device struct 86 * @regs: mapped MMIO region 87 * @irq: interrupt number, can be shared with other DARTs 88 * @clks: clocks associated with this DART 89 * @num_clks: number of @clks 90 * @lock: lock for hardware operations involving this dart 91 * @pgsize: pagesize supported by this DART 92 * @supports_bypass: indicates if this DART supports bypass mode 93 * @force_bypass: force bypass mode due to pagesize mismatch? 94 * @sid2group: maps stream ids to iommu_groups 95 * @iommu: iommu core device 96 */ 97 struct apple_dart { 98 struct device *dev; 99 100 void __iomem *regs; 101 102 int irq; 103 struct clk_bulk_data *clks; 104 int num_clks; 105 106 spinlock_t lock; 107 108 u32 pgsize; 109 u32 supports_bypass : 1; 110 u32 force_bypass : 1; 111 112 struct iommu_group *sid2group[DART_MAX_STREAMS]; 113 struct iommu_device iommu; 114 }; 115 116 /* 117 * Convenience struct to identify streams. 118 * 119 * The normal variant is used inside apple_dart_master_cfg which isn't written 120 * to concurrently. 121 * The atomic variant is used inside apple_dart_domain where we have to guard 122 * against races from potential parallel calls to attach/detach_device. 123 * Note that even inside the atomic variant the apple_dart pointer is not 124 * protected: This pointer is initialized once under the domain init mutex 125 * and never changed again afterwards. Devices with different dart pointers 126 * cannot be attached to the same domain. 127 * 128 * @dart dart pointer 129 * @sid stream id bitmap 130 */ 131 struct apple_dart_stream_map { 132 struct apple_dart *dart; 133 unsigned long sidmap; 134 }; 135 struct apple_dart_atomic_stream_map { 136 struct apple_dart *dart; 137 atomic64_t sidmap; 138 }; 139 140 /* 141 * This structure is attached to each iommu domain handled by a DART. 142 * 143 * @pgtbl_ops: pagetable ops allocated by io-pgtable 144 * @finalized: true if the domain has been completely initialized 145 * @init_lock: protects domain initialization 146 * @stream_maps: streams attached to this domain (valid for DMA/UNMANAGED only) 147 * @domain: core iommu domain pointer 148 */ 149 struct apple_dart_domain { 150 struct io_pgtable_ops *pgtbl_ops; 151 152 bool finalized; 153 struct mutex init_lock; 154 struct apple_dart_atomic_stream_map stream_maps[MAX_DARTS_PER_DEVICE]; 155 156 struct iommu_domain domain; 157 }; 158 159 /* 160 * This structure is attached to devices with dev_iommu_priv_set() on of_xlate 161 * and contains a list of streams bound to this device. 162 * So far the worst case seen is a single device with two streams 163 * from different darts, such that this simple static array is enough. 164 * 165 * @streams: streams for this device 166 */ 167 struct apple_dart_master_cfg { 168 struct apple_dart_stream_map stream_maps[MAX_DARTS_PER_DEVICE]; 169 }; 170 171 /* 172 * Helper macro to iterate over apple_dart_master_cfg.stream_maps and 173 * apple_dart_domain.stream_maps 174 * 175 * @i int used as loop variable 176 * @base pointer to base struct (apple_dart_master_cfg or apple_dart_domain) 177 * @stream pointer to the apple_dart_streams struct for each loop iteration 178 */ 179 #define for_each_stream_map(i, base, stream_map) \ 180 for (i = 0, stream_map = &(base)->stream_maps[0]; \ 181 i < MAX_DARTS_PER_DEVICE && stream_map->dart; \ 182 stream_map = &(base)->stream_maps[++i]) 183 184 static struct platform_driver apple_dart_driver; 185 static const struct iommu_ops apple_dart_iommu_ops; 186 static const struct iommu_flush_ops apple_dart_tlb_ops; 187 188 static struct apple_dart_domain *to_dart_domain(struct iommu_domain *dom) 189 { 190 return container_of(dom, struct apple_dart_domain, domain); 191 } 192 193 static void 194 apple_dart_hw_enable_translation(struct apple_dart_stream_map *stream_map) 195 { 196 int sid; 197 198 for_each_set_bit(sid, &stream_map->sidmap, DART_MAX_STREAMS) 199 writel(DART_TCR_TRANSLATE_ENABLE, 200 stream_map->dart->regs + DART_TCR(sid)); 201 } 202 203 static void apple_dart_hw_disable_dma(struct apple_dart_stream_map *stream_map) 204 { 205 int sid; 206 207 for_each_set_bit(sid, &stream_map->sidmap, DART_MAX_STREAMS) 208 writel(0, stream_map->dart->regs + DART_TCR(sid)); 209 } 210 211 static void 212 apple_dart_hw_enable_bypass(struct apple_dart_stream_map *stream_map) 213 { 214 int sid; 215 216 WARN_ON(!stream_map->dart->supports_bypass); 217 for_each_set_bit(sid, &stream_map->sidmap, DART_MAX_STREAMS) 218 writel(DART_TCR_BYPASS0_ENABLE | DART_TCR_BYPASS1_ENABLE, 219 stream_map->dart->regs + DART_TCR(sid)); 220 } 221 222 static void apple_dart_hw_set_ttbr(struct apple_dart_stream_map *stream_map, 223 u8 idx, phys_addr_t paddr) 224 { 225 int sid; 226 227 WARN_ON(paddr & ((1 << DART_TTBR_SHIFT) - 1)); 228 for_each_set_bit(sid, &stream_map->sidmap, DART_MAX_STREAMS) 229 writel(DART_TTBR_VALID | (paddr >> DART_TTBR_SHIFT), 230 stream_map->dart->regs + DART_TTBR(sid, idx)); 231 } 232 233 static void apple_dart_hw_clear_ttbr(struct apple_dart_stream_map *stream_map, 234 u8 idx) 235 { 236 int sid; 237 238 for_each_set_bit(sid, &stream_map->sidmap, DART_MAX_STREAMS) 239 writel(0, stream_map->dart->regs + DART_TTBR(sid, idx)); 240 } 241 242 static void 243 apple_dart_hw_clear_all_ttbrs(struct apple_dart_stream_map *stream_map) 244 { 245 int i; 246 247 for (i = 0; i < DART_MAX_TTBR; ++i) 248 apple_dart_hw_clear_ttbr(stream_map, i); 249 } 250 251 static int 252 apple_dart_hw_stream_command(struct apple_dart_stream_map *stream_map, 253 u32 command) 254 { 255 unsigned long flags; 256 int ret; 257 u32 command_reg; 258 259 spin_lock_irqsave(&stream_map->dart->lock, flags); 260 261 writel(stream_map->sidmap, stream_map->dart->regs + DART_STREAM_SELECT); 262 writel(command, stream_map->dart->regs + DART_STREAM_COMMAND); 263 264 ret = readl_poll_timeout_atomic( 265 stream_map->dart->regs + DART_STREAM_COMMAND, command_reg, 266 !(command_reg & DART_STREAM_COMMAND_BUSY), 1, 267 DART_STREAM_COMMAND_BUSY_TIMEOUT); 268 269 spin_unlock_irqrestore(&stream_map->dart->lock, flags); 270 271 if (ret) { 272 dev_err(stream_map->dart->dev, 273 "busy bit did not clear after command %x for streams %lx\n", 274 command, stream_map->sidmap); 275 return ret; 276 } 277 278 return 0; 279 } 280 281 static int 282 apple_dart_hw_invalidate_tlb(struct apple_dart_stream_map *stream_map) 283 { 284 return apple_dart_hw_stream_command(stream_map, 285 DART_STREAM_COMMAND_INVALIDATE); 286 } 287 288 static int apple_dart_hw_reset(struct apple_dart *dart) 289 { 290 u32 config; 291 struct apple_dart_stream_map stream_map; 292 293 config = readl(dart->regs + DART_CONFIG); 294 if (config & DART_CONFIG_LOCK) { 295 dev_err(dart->dev, "DART is locked down until reboot: %08x\n", 296 config); 297 return -EINVAL; 298 } 299 300 stream_map.dart = dart; 301 stream_map.sidmap = DART_STREAM_ALL; 302 apple_dart_hw_disable_dma(&stream_map); 303 apple_dart_hw_clear_all_ttbrs(&stream_map); 304 305 /* clear any pending errors before the interrupt is unmasked */ 306 writel(readl(dart->regs + DART_ERROR), dart->regs + DART_ERROR); 307 308 return apple_dart_hw_invalidate_tlb(&stream_map); 309 } 310 311 static void apple_dart_domain_flush_tlb(struct apple_dart_domain *domain) 312 { 313 int i; 314 struct apple_dart_atomic_stream_map *domain_stream_map; 315 struct apple_dart_stream_map stream_map; 316 317 for_each_stream_map(i, domain, domain_stream_map) { 318 stream_map.dart = domain_stream_map->dart; 319 stream_map.sidmap = atomic64_read(&domain_stream_map->sidmap); 320 apple_dart_hw_invalidate_tlb(&stream_map); 321 } 322 } 323 324 static void apple_dart_flush_iotlb_all(struct iommu_domain *domain) 325 { 326 apple_dart_domain_flush_tlb(to_dart_domain(domain)); 327 } 328 329 static void apple_dart_iotlb_sync(struct iommu_domain *domain, 330 struct iommu_iotlb_gather *gather) 331 { 332 apple_dart_domain_flush_tlb(to_dart_domain(domain)); 333 } 334 335 static void apple_dart_iotlb_sync_map(struct iommu_domain *domain, 336 unsigned long iova, size_t size) 337 { 338 apple_dart_domain_flush_tlb(to_dart_domain(domain)); 339 } 340 341 static void apple_dart_tlb_flush_all(void *cookie) 342 { 343 apple_dart_domain_flush_tlb(cookie); 344 } 345 346 static void apple_dart_tlb_flush_walk(unsigned long iova, size_t size, 347 size_t granule, void *cookie) 348 { 349 apple_dart_domain_flush_tlb(cookie); 350 } 351 352 static const struct iommu_flush_ops apple_dart_tlb_ops = { 353 .tlb_flush_all = apple_dart_tlb_flush_all, 354 .tlb_flush_walk = apple_dart_tlb_flush_walk, 355 }; 356 357 static phys_addr_t apple_dart_iova_to_phys(struct iommu_domain *domain, 358 dma_addr_t iova) 359 { 360 struct apple_dart_domain *dart_domain = to_dart_domain(domain); 361 struct io_pgtable_ops *ops = dart_domain->pgtbl_ops; 362 363 if (!ops) 364 return 0; 365 366 return ops->iova_to_phys(ops, iova); 367 } 368 369 static int apple_dart_map_pages(struct iommu_domain *domain, unsigned long iova, 370 phys_addr_t paddr, size_t pgsize, 371 size_t pgcount, int prot, gfp_t gfp, 372 size_t *mapped) 373 { 374 struct apple_dart_domain *dart_domain = to_dart_domain(domain); 375 struct io_pgtable_ops *ops = dart_domain->pgtbl_ops; 376 377 if (!ops) 378 return -ENODEV; 379 380 return ops->map_pages(ops, iova, paddr, pgsize, pgcount, prot, gfp, 381 mapped); 382 } 383 384 static size_t apple_dart_unmap_pages(struct iommu_domain *domain, 385 unsigned long iova, size_t pgsize, 386 size_t pgcount, 387 struct iommu_iotlb_gather *gather) 388 { 389 struct apple_dart_domain *dart_domain = to_dart_domain(domain); 390 struct io_pgtable_ops *ops = dart_domain->pgtbl_ops; 391 392 return ops->unmap_pages(ops, iova, pgsize, pgcount, gather); 393 } 394 395 static void 396 apple_dart_setup_translation(struct apple_dart_domain *domain, 397 struct apple_dart_stream_map *stream_map) 398 { 399 int i; 400 struct io_pgtable_cfg *pgtbl_cfg = 401 &io_pgtable_ops_to_pgtable(domain->pgtbl_ops)->cfg; 402 403 for (i = 0; i < pgtbl_cfg->apple_dart_cfg.n_ttbrs; ++i) 404 apple_dart_hw_set_ttbr(stream_map, i, 405 pgtbl_cfg->apple_dart_cfg.ttbr[i]); 406 for (; i < DART_MAX_TTBR; ++i) 407 apple_dart_hw_clear_ttbr(stream_map, i); 408 409 apple_dart_hw_enable_translation(stream_map); 410 apple_dart_hw_invalidate_tlb(stream_map); 411 } 412 413 static int apple_dart_finalize_domain(struct iommu_domain *domain, 414 struct apple_dart_master_cfg *cfg) 415 { 416 struct apple_dart_domain *dart_domain = to_dart_domain(domain); 417 struct apple_dart *dart = cfg->stream_maps[0].dart; 418 struct io_pgtable_cfg pgtbl_cfg; 419 int ret = 0; 420 int i; 421 422 mutex_lock(&dart_domain->init_lock); 423 424 if (dart_domain->finalized) 425 goto done; 426 427 for (i = 0; i < MAX_DARTS_PER_DEVICE; ++i) { 428 dart_domain->stream_maps[i].dart = cfg->stream_maps[i].dart; 429 atomic64_set(&dart_domain->stream_maps[i].sidmap, 430 cfg->stream_maps[i].sidmap); 431 } 432 433 pgtbl_cfg = (struct io_pgtable_cfg){ 434 .pgsize_bitmap = dart->pgsize, 435 .ias = 32, 436 .oas = 36, 437 .coherent_walk = 1, 438 .tlb = &apple_dart_tlb_ops, 439 .iommu_dev = dart->dev, 440 }; 441 442 dart_domain->pgtbl_ops = 443 alloc_io_pgtable_ops(APPLE_DART, &pgtbl_cfg, domain); 444 if (!dart_domain->pgtbl_ops) { 445 ret = -ENOMEM; 446 goto done; 447 } 448 449 domain->pgsize_bitmap = pgtbl_cfg.pgsize_bitmap; 450 domain->geometry.aperture_start = 0; 451 domain->geometry.aperture_end = DMA_BIT_MASK(32); 452 domain->geometry.force_aperture = true; 453 454 dart_domain->finalized = true; 455 456 done: 457 mutex_unlock(&dart_domain->init_lock); 458 return ret; 459 } 460 461 static int 462 apple_dart_mod_streams(struct apple_dart_atomic_stream_map *domain_maps, 463 struct apple_dart_stream_map *master_maps, 464 bool add_streams) 465 { 466 int i; 467 468 for (i = 0; i < MAX_DARTS_PER_DEVICE; ++i) { 469 if (domain_maps[i].dart != master_maps[i].dart) 470 return -EINVAL; 471 } 472 473 for (i = 0; i < MAX_DARTS_PER_DEVICE; ++i) { 474 if (!domain_maps[i].dart) 475 break; 476 if (add_streams) 477 atomic64_or(master_maps[i].sidmap, 478 &domain_maps[i].sidmap); 479 else 480 atomic64_and(~master_maps[i].sidmap, 481 &domain_maps[i].sidmap); 482 } 483 484 return 0; 485 } 486 487 static int apple_dart_domain_add_streams(struct apple_dart_domain *domain, 488 struct apple_dart_master_cfg *cfg) 489 { 490 return apple_dart_mod_streams(domain->stream_maps, cfg->stream_maps, 491 true); 492 } 493 494 static int apple_dart_domain_remove_streams(struct apple_dart_domain *domain, 495 struct apple_dart_master_cfg *cfg) 496 { 497 return apple_dart_mod_streams(domain->stream_maps, cfg->stream_maps, 498 false); 499 } 500 501 static int apple_dart_attach_dev(struct iommu_domain *domain, 502 struct device *dev) 503 { 504 int ret, i; 505 struct apple_dart_stream_map *stream_map; 506 struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev); 507 struct apple_dart_domain *dart_domain = to_dart_domain(domain); 508 509 if (cfg->stream_maps[0].dart->force_bypass && 510 domain->type != IOMMU_DOMAIN_IDENTITY) 511 return -EINVAL; 512 if (!cfg->stream_maps[0].dart->supports_bypass && 513 domain->type == IOMMU_DOMAIN_IDENTITY) 514 return -EINVAL; 515 516 ret = apple_dart_finalize_domain(domain, cfg); 517 if (ret) 518 return ret; 519 520 switch (domain->type) { 521 case IOMMU_DOMAIN_DMA: 522 case IOMMU_DOMAIN_UNMANAGED: 523 ret = apple_dart_domain_add_streams(dart_domain, cfg); 524 if (ret) 525 return ret; 526 527 for_each_stream_map(i, cfg, stream_map) 528 apple_dart_setup_translation(dart_domain, stream_map); 529 break; 530 case IOMMU_DOMAIN_BLOCKED: 531 for_each_stream_map(i, cfg, stream_map) 532 apple_dart_hw_disable_dma(stream_map); 533 break; 534 case IOMMU_DOMAIN_IDENTITY: 535 for_each_stream_map(i, cfg, stream_map) 536 apple_dart_hw_enable_bypass(stream_map); 537 break; 538 } 539 540 return ret; 541 } 542 543 static void apple_dart_detach_dev(struct iommu_domain *domain, 544 struct device *dev) 545 { 546 int i; 547 struct apple_dart_stream_map *stream_map; 548 struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev); 549 struct apple_dart_domain *dart_domain = to_dart_domain(domain); 550 551 for_each_stream_map(i, cfg, stream_map) 552 apple_dart_hw_disable_dma(stream_map); 553 554 if (domain->type == IOMMU_DOMAIN_DMA || 555 domain->type == IOMMU_DOMAIN_UNMANAGED) 556 apple_dart_domain_remove_streams(dart_domain, cfg); 557 } 558 559 static struct iommu_device *apple_dart_probe_device(struct device *dev) 560 { 561 struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev); 562 struct apple_dart_stream_map *stream_map; 563 int i; 564 565 if (!cfg) 566 return ERR_PTR(-ENODEV); 567 568 for_each_stream_map(i, cfg, stream_map) 569 device_link_add( 570 dev, stream_map->dart->dev, 571 DL_FLAG_PM_RUNTIME | DL_FLAG_AUTOREMOVE_SUPPLIER); 572 573 return &cfg->stream_maps[0].dart->iommu; 574 } 575 576 static void apple_dart_release_device(struct device *dev) 577 { 578 struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev); 579 580 if (!cfg) 581 return; 582 583 dev_iommu_priv_set(dev, NULL); 584 kfree(cfg); 585 } 586 587 static struct iommu_domain *apple_dart_domain_alloc(unsigned int type) 588 { 589 struct apple_dart_domain *dart_domain; 590 591 if (type != IOMMU_DOMAIN_DMA && type != IOMMU_DOMAIN_UNMANAGED && 592 type != IOMMU_DOMAIN_IDENTITY && type != IOMMU_DOMAIN_BLOCKED) 593 return NULL; 594 595 dart_domain = kzalloc(sizeof(*dart_domain), GFP_KERNEL); 596 if (!dart_domain) 597 return NULL; 598 599 iommu_get_dma_cookie(&dart_domain->domain); 600 mutex_init(&dart_domain->init_lock); 601 602 /* no need to allocate pgtbl_ops or do any other finalization steps */ 603 if (type == IOMMU_DOMAIN_IDENTITY || type == IOMMU_DOMAIN_BLOCKED) 604 dart_domain->finalized = true; 605 606 return &dart_domain->domain; 607 } 608 609 static void apple_dart_domain_free(struct iommu_domain *domain) 610 { 611 struct apple_dart_domain *dart_domain = to_dart_domain(domain); 612 613 if (dart_domain->pgtbl_ops) 614 free_io_pgtable_ops(dart_domain->pgtbl_ops); 615 616 kfree(dart_domain); 617 } 618 619 static int apple_dart_of_xlate(struct device *dev, struct of_phandle_args *args) 620 { 621 struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev); 622 struct platform_device *iommu_pdev = of_find_device_by_node(args->np); 623 struct apple_dart *dart = platform_get_drvdata(iommu_pdev); 624 struct apple_dart *cfg_dart; 625 int i, sid; 626 627 if (args->args_count != 1) 628 return -EINVAL; 629 sid = args->args[0]; 630 631 if (!cfg) 632 cfg = kzalloc(sizeof(*cfg), GFP_KERNEL); 633 if (!cfg) 634 return -ENOMEM; 635 dev_iommu_priv_set(dev, cfg); 636 637 cfg_dart = cfg->stream_maps[0].dart; 638 if (cfg_dart) { 639 if (cfg_dart->supports_bypass != dart->supports_bypass) 640 return -EINVAL; 641 if (cfg_dart->force_bypass != dart->force_bypass) 642 return -EINVAL; 643 if (cfg_dart->pgsize != dart->pgsize) 644 return -EINVAL; 645 } 646 647 for (i = 0; i < MAX_DARTS_PER_DEVICE; ++i) { 648 if (cfg->stream_maps[i].dart == dart) { 649 cfg->stream_maps[i].sidmap |= 1 << sid; 650 return 0; 651 } 652 } 653 for (i = 0; i < MAX_DARTS_PER_DEVICE; ++i) { 654 if (!cfg->stream_maps[i].dart) { 655 cfg->stream_maps[i].dart = dart; 656 cfg->stream_maps[i].sidmap = 1 << sid; 657 return 0; 658 } 659 } 660 661 return -EINVAL; 662 } 663 664 static struct iommu_group *apple_dart_device_group(struct device *dev) 665 { 666 static DEFINE_MUTEX(lock); 667 int i, sid; 668 struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev); 669 struct apple_dart_stream_map *stream_map; 670 struct iommu_group *group = NULL; 671 struct iommu_group *res = ERR_PTR(-EINVAL); 672 673 mutex_lock(&lock); 674 675 for_each_stream_map(i, cfg, stream_map) { 676 for_each_set_bit(sid, &stream_map->sidmap, DART_MAX_STREAMS) { 677 struct iommu_group *stream_group = 678 stream_map->dart->sid2group[sid]; 679 680 if (group && group != stream_group) { 681 res = ERR_PTR(-EINVAL); 682 goto out; 683 } 684 685 group = stream_group; 686 } 687 } 688 689 if (group) { 690 res = iommu_group_ref_get(group); 691 goto out; 692 } 693 694 #ifdef CONFIG_PCI 695 if (dev_is_pci(dev)) 696 group = pci_device_group(dev); 697 else 698 #endif 699 group = generic_device_group(dev); 700 701 for_each_stream_map(i, cfg, stream_map) 702 for_each_set_bit(sid, &stream_map->sidmap, DART_MAX_STREAMS) 703 stream_map->dart->sid2group[sid] = group; 704 705 res = group; 706 707 out: 708 mutex_unlock(&lock); 709 return res; 710 } 711 712 static int apple_dart_def_domain_type(struct device *dev) 713 { 714 struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev); 715 716 if (cfg->stream_maps[0].dart->force_bypass) 717 return IOMMU_DOMAIN_IDENTITY; 718 if (!cfg->stream_maps[0].dart->supports_bypass) 719 return IOMMU_DOMAIN_DMA; 720 721 return 0; 722 } 723 724 static const struct iommu_ops apple_dart_iommu_ops = { 725 .domain_alloc = apple_dart_domain_alloc, 726 .domain_free = apple_dart_domain_free, 727 .attach_dev = apple_dart_attach_dev, 728 .detach_dev = apple_dart_detach_dev, 729 .map_pages = apple_dart_map_pages, 730 .unmap_pages = apple_dart_unmap_pages, 731 .flush_iotlb_all = apple_dart_flush_iotlb_all, 732 .iotlb_sync = apple_dart_iotlb_sync, 733 .iotlb_sync_map = apple_dart_iotlb_sync_map, 734 .iova_to_phys = apple_dart_iova_to_phys, 735 .probe_device = apple_dart_probe_device, 736 .release_device = apple_dart_release_device, 737 .device_group = apple_dart_device_group, 738 .of_xlate = apple_dart_of_xlate, 739 .def_domain_type = apple_dart_def_domain_type, 740 .pgsize_bitmap = -1UL, /* Restricted during dart probe */ 741 }; 742 743 static irqreturn_t apple_dart_irq(int irq, void *dev) 744 { 745 struct apple_dart *dart = dev; 746 const char *fault_name = NULL; 747 u32 error = readl(dart->regs + DART_ERROR); 748 u32 error_code = FIELD_GET(DART_ERROR_CODE, error); 749 u32 addr_lo = readl(dart->regs + DART_ERROR_ADDR_LO); 750 u32 addr_hi = readl(dart->regs + DART_ERROR_ADDR_HI); 751 u64 addr = addr_lo | (((u64)addr_hi) << 32); 752 u8 stream_idx = FIELD_GET(DART_ERROR_STREAM, error); 753 754 if (!(error & DART_ERROR_FLAG)) 755 return IRQ_NONE; 756 757 /* there should only be a single bit set but let's use == to be sure */ 758 if (error_code == DART_ERROR_READ_FAULT) 759 fault_name = "READ FAULT"; 760 else if (error_code == DART_ERROR_WRITE_FAULT) 761 fault_name = "WRITE FAULT"; 762 else if (error_code == DART_ERROR_NO_PTE) 763 fault_name = "NO PTE FOR IOVA"; 764 else if (error_code == DART_ERROR_NO_PMD) 765 fault_name = "NO PMD FOR IOVA"; 766 else if (error_code == DART_ERROR_NO_TTBR) 767 fault_name = "NO TTBR FOR IOVA"; 768 else 769 fault_name = "unknown"; 770 771 dev_err_ratelimited( 772 dart->dev, 773 "translation fault: status:0x%x stream:%d code:0x%x (%s) at 0x%llx", 774 error, stream_idx, error_code, fault_name, addr); 775 776 writel(error, dart->regs + DART_ERROR); 777 return IRQ_HANDLED; 778 } 779 780 static int apple_dart_set_bus_ops(const struct iommu_ops *ops) 781 { 782 int ret; 783 784 if (!iommu_present(&platform_bus_type)) { 785 ret = bus_set_iommu(&platform_bus_type, ops); 786 if (ret) 787 return ret; 788 } 789 #ifdef CONFIG_PCI 790 if (!iommu_present(&pci_bus_type)) { 791 ret = bus_set_iommu(&pci_bus_type, ops); 792 if (ret) { 793 bus_set_iommu(&platform_bus_type, NULL); 794 return ret; 795 } 796 } 797 #endif 798 return 0; 799 } 800 801 static int apple_dart_probe(struct platform_device *pdev) 802 { 803 int ret; 804 u32 dart_params[2]; 805 struct resource *res; 806 struct apple_dart *dart; 807 struct device *dev = &pdev->dev; 808 809 dart = devm_kzalloc(dev, sizeof(*dart), GFP_KERNEL); 810 if (!dart) 811 return -ENOMEM; 812 813 dart->dev = dev; 814 spin_lock_init(&dart->lock); 815 816 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 817 if (resource_size(res) < 0x4000) { 818 dev_err(dev, "MMIO region too small (%pr)\n", res); 819 return -EINVAL; 820 } 821 822 dart->regs = devm_ioremap_resource(dev, res); 823 if (IS_ERR(dart->regs)) 824 return PTR_ERR(dart->regs); 825 826 dart->irq = platform_get_irq(pdev, 0); 827 if (dart->irq < 0) 828 return -ENODEV; 829 830 ret = devm_clk_bulk_get_all(dev, &dart->clks); 831 if (ret < 0) 832 return ret; 833 dart->num_clks = ret; 834 835 ret = clk_bulk_prepare_enable(dart->num_clks, dart->clks); 836 if (ret) 837 return ret; 838 839 ret = apple_dart_hw_reset(dart); 840 if (ret) 841 goto err_clk_disable; 842 843 dart_params[0] = readl(dart->regs + DART_PARAMS1); 844 dart_params[1] = readl(dart->regs + DART_PARAMS2); 845 dart->pgsize = 1 << FIELD_GET(DART_PARAMS_PAGE_SHIFT, dart_params[0]); 846 dart->supports_bypass = dart_params[1] & DART_PARAMS_BYPASS_SUPPORT; 847 dart->force_bypass = dart->pgsize > PAGE_SIZE; 848 849 ret = request_irq(dart->irq, apple_dart_irq, IRQF_SHARED, 850 "apple-dart fault handler", dart); 851 if (ret) 852 goto err_clk_disable; 853 854 platform_set_drvdata(pdev, dart); 855 856 ret = apple_dart_set_bus_ops(&apple_dart_iommu_ops); 857 if (ret) 858 goto err_free_irq; 859 860 ret = iommu_device_sysfs_add(&dart->iommu, dev, NULL, "apple-dart.%s", 861 dev_name(&pdev->dev)); 862 if (ret) 863 goto err_remove_bus_ops; 864 865 ret = iommu_device_register(&dart->iommu, &apple_dart_iommu_ops, dev); 866 if (ret) 867 goto err_sysfs_remove; 868 869 dev_info( 870 &pdev->dev, 871 "DART [pagesize %x, bypass support: %d, bypass forced: %d] initialized\n", 872 dart->pgsize, dart->supports_bypass, dart->force_bypass); 873 return 0; 874 875 err_sysfs_remove: 876 iommu_device_sysfs_remove(&dart->iommu); 877 err_remove_bus_ops: 878 apple_dart_set_bus_ops(NULL); 879 err_free_irq: 880 free_irq(dart->irq, dart); 881 err_clk_disable: 882 clk_bulk_disable_unprepare(dart->num_clks, dart->clks); 883 884 return ret; 885 } 886 887 static int apple_dart_remove(struct platform_device *pdev) 888 { 889 struct apple_dart *dart = platform_get_drvdata(pdev); 890 891 apple_dart_hw_reset(dart); 892 free_irq(dart->irq, dart); 893 apple_dart_set_bus_ops(NULL); 894 895 iommu_device_unregister(&dart->iommu); 896 iommu_device_sysfs_remove(&dart->iommu); 897 898 clk_bulk_disable_unprepare(dart->num_clks, dart->clks); 899 900 return 0; 901 } 902 903 static const struct of_device_id apple_dart_of_match[] = { 904 { .compatible = "apple,t8103-dart", .data = NULL }, 905 {}, 906 }; 907 MODULE_DEVICE_TABLE(of, apple_dart_of_match); 908 909 static struct platform_driver apple_dart_driver = { 910 .driver = { 911 .name = "apple-dart", 912 .of_match_table = apple_dart_of_match, 913 .suppress_bind_attrs = true, 914 }, 915 .probe = apple_dart_probe, 916 .remove = apple_dart_remove, 917 }; 918 919 module_platform_driver(apple_dart_driver); 920 921 MODULE_DESCRIPTION("IOMMU API for Apple's DART"); 922 MODULE_AUTHOR("Sven Peter <sven@svenpeter.dev>"); 923 MODULE_LICENSE("GPL v2"); 924