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_STREAMS_ENABLE 0xfc 74 75 #define DART_TCR(sid) (0x100 + 4 * (sid)) 76 #define DART_TCR_TRANSLATE_ENABLE BIT(7) 77 #define DART_TCR_BYPASS0_ENABLE BIT(8) 78 #define DART_TCR_BYPASS1_ENABLE BIT(12) 79 80 #define DART_TTBR(sid, idx) (0x200 + 16 * (sid) + 4 * (idx)) 81 #define DART_TTBR_VALID BIT(31) 82 #define DART_TTBR_SHIFT 12 83 84 /* 85 * Private structure associated with each DART device. 86 * 87 * @dev: device struct 88 * @regs: mapped MMIO region 89 * @irq: interrupt number, can be shared with other DARTs 90 * @clks: clocks associated with this DART 91 * @num_clks: number of @clks 92 * @lock: lock for hardware operations involving this dart 93 * @pgsize: pagesize supported by this DART 94 * @supports_bypass: indicates if this DART supports bypass mode 95 * @force_bypass: force bypass mode due to pagesize mismatch? 96 * @sid2group: maps stream ids to iommu_groups 97 * @iommu: iommu core device 98 */ 99 struct apple_dart { 100 struct device *dev; 101 102 void __iomem *regs; 103 104 int irq; 105 struct clk_bulk_data *clks; 106 int num_clks; 107 108 spinlock_t lock; 109 110 u32 pgsize; 111 u32 supports_bypass : 1; 112 u32 force_bypass : 1; 113 114 struct iommu_group *sid2group[DART_MAX_STREAMS]; 115 struct iommu_device iommu; 116 }; 117 118 /* 119 * Convenience struct to identify streams. 120 * 121 * The normal variant is used inside apple_dart_master_cfg which isn't written 122 * to concurrently. 123 * The atomic variant is used inside apple_dart_domain where we have to guard 124 * against races from potential parallel calls to attach/detach_device. 125 * Note that even inside the atomic variant the apple_dart pointer is not 126 * protected: This pointer is initialized once under the domain init mutex 127 * and never changed again afterwards. Devices with different dart pointers 128 * cannot be attached to the same domain. 129 * 130 * @dart dart pointer 131 * @sid stream id bitmap 132 */ 133 struct apple_dart_stream_map { 134 struct apple_dart *dart; 135 unsigned long sidmap; 136 }; 137 struct apple_dart_atomic_stream_map { 138 struct apple_dart *dart; 139 atomic64_t sidmap; 140 }; 141 142 /* 143 * This structure is attached to each iommu domain handled by a DART. 144 * 145 * @pgtbl_ops: pagetable ops allocated by io-pgtable 146 * @finalized: true if the domain has been completely initialized 147 * @init_lock: protects domain initialization 148 * @stream_maps: streams attached to this domain (valid for DMA/UNMANAGED only) 149 * @domain: core iommu domain pointer 150 */ 151 struct apple_dart_domain { 152 struct io_pgtable_ops *pgtbl_ops; 153 154 bool finalized; 155 struct mutex init_lock; 156 struct apple_dart_atomic_stream_map stream_maps[MAX_DARTS_PER_DEVICE]; 157 158 struct iommu_domain domain; 159 }; 160 161 /* 162 * This structure is attached to devices with dev_iommu_priv_set() on of_xlate 163 * and contains a list of streams bound to this device. 164 * So far the worst case seen is a single device with two streams 165 * from different darts, such that this simple static array is enough. 166 * 167 * @streams: streams for this device 168 */ 169 struct apple_dart_master_cfg { 170 struct apple_dart_stream_map stream_maps[MAX_DARTS_PER_DEVICE]; 171 }; 172 173 /* 174 * Helper macro to iterate over apple_dart_master_cfg.stream_maps and 175 * apple_dart_domain.stream_maps 176 * 177 * @i int used as loop variable 178 * @base pointer to base struct (apple_dart_master_cfg or apple_dart_domain) 179 * @stream pointer to the apple_dart_streams struct for each loop iteration 180 */ 181 #define for_each_stream_map(i, base, stream_map) \ 182 for (i = 0, stream_map = &(base)->stream_maps[0]; \ 183 i < MAX_DARTS_PER_DEVICE && stream_map->dart; \ 184 stream_map = &(base)->stream_maps[++i]) 185 186 static struct platform_driver apple_dart_driver; 187 static const struct iommu_ops apple_dart_iommu_ops; 188 189 static struct apple_dart_domain *to_dart_domain(struct iommu_domain *dom) 190 { 191 return container_of(dom, struct apple_dart_domain, domain); 192 } 193 194 static void 195 apple_dart_hw_enable_translation(struct apple_dart_stream_map *stream_map) 196 { 197 int sid; 198 199 for_each_set_bit(sid, &stream_map->sidmap, DART_MAX_STREAMS) 200 writel(DART_TCR_TRANSLATE_ENABLE, 201 stream_map->dart->regs + DART_TCR(sid)); 202 } 203 204 static void apple_dart_hw_disable_dma(struct apple_dart_stream_map *stream_map) 205 { 206 int sid; 207 208 for_each_set_bit(sid, &stream_map->sidmap, DART_MAX_STREAMS) 209 writel(0, stream_map->dart->regs + DART_TCR(sid)); 210 } 211 212 static void 213 apple_dart_hw_enable_bypass(struct apple_dart_stream_map *stream_map) 214 { 215 int sid; 216 217 WARN_ON(!stream_map->dart->supports_bypass); 218 for_each_set_bit(sid, &stream_map->sidmap, DART_MAX_STREAMS) 219 writel(DART_TCR_BYPASS0_ENABLE | DART_TCR_BYPASS1_ENABLE, 220 stream_map->dart->regs + DART_TCR(sid)); 221 } 222 223 static void apple_dart_hw_set_ttbr(struct apple_dart_stream_map *stream_map, 224 u8 idx, phys_addr_t paddr) 225 { 226 int sid; 227 228 WARN_ON(paddr & ((1 << DART_TTBR_SHIFT) - 1)); 229 for_each_set_bit(sid, &stream_map->sidmap, DART_MAX_STREAMS) 230 writel(DART_TTBR_VALID | (paddr >> DART_TTBR_SHIFT), 231 stream_map->dart->regs + DART_TTBR(sid, idx)); 232 } 233 234 static void apple_dart_hw_clear_ttbr(struct apple_dart_stream_map *stream_map, 235 u8 idx) 236 { 237 int sid; 238 239 for_each_set_bit(sid, &stream_map->sidmap, DART_MAX_STREAMS) 240 writel(0, stream_map->dart->regs + DART_TTBR(sid, idx)); 241 } 242 243 static void 244 apple_dart_hw_clear_all_ttbrs(struct apple_dart_stream_map *stream_map) 245 { 246 int i; 247 248 for (i = 0; i < DART_MAX_TTBR; ++i) 249 apple_dart_hw_clear_ttbr(stream_map, i); 250 } 251 252 static int 253 apple_dart_hw_stream_command(struct apple_dart_stream_map *stream_map, 254 u32 command) 255 { 256 unsigned long flags; 257 int ret; 258 u32 command_reg; 259 260 spin_lock_irqsave(&stream_map->dart->lock, flags); 261 262 writel(stream_map->sidmap, stream_map->dart->regs + DART_STREAM_SELECT); 263 writel(command, stream_map->dart->regs + DART_STREAM_COMMAND); 264 265 ret = readl_poll_timeout_atomic( 266 stream_map->dart->regs + DART_STREAM_COMMAND, command_reg, 267 !(command_reg & DART_STREAM_COMMAND_BUSY), 1, 268 DART_STREAM_COMMAND_BUSY_TIMEOUT); 269 270 spin_unlock_irqrestore(&stream_map->dart->lock, flags); 271 272 if (ret) { 273 dev_err(stream_map->dart->dev, 274 "busy bit did not clear after command %x for streams %lx\n", 275 command, stream_map->sidmap); 276 return ret; 277 } 278 279 return 0; 280 } 281 282 static int 283 apple_dart_hw_invalidate_tlb(struct apple_dart_stream_map *stream_map) 284 { 285 return apple_dart_hw_stream_command(stream_map, 286 DART_STREAM_COMMAND_INVALIDATE); 287 } 288 289 static int apple_dart_hw_reset(struct apple_dart *dart) 290 { 291 u32 config; 292 struct apple_dart_stream_map stream_map; 293 294 config = readl(dart->regs + DART_CONFIG); 295 if (config & DART_CONFIG_LOCK) { 296 dev_err(dart->dev, "DART is locked down until reboot: %08x\n", 297 config); 298 return -EINVAL; 299 } 300 301 stream_map.dart = dart; 302 stream_map.sidmap = DART_STREAM_ALL; 303 apple_dart_hw_disable_dma(&stream_map); 304 apple_dart_hw_clear_all_ttbrs(&stream_map); 305 306 /* enable all streams globally since TCR is used to control isolation */ 307 writel(DART_STREAM_ALL, dart->regs + DART_STREAMS_ENABLE); 308 309 /* clear any pending errors before the interrupt is unmasked */ 310 writel(readl(dart->regs + DART_ERROR), dart->regs + DART_ERROR); 311 312 return apple_dart_hw_invalidate_tlb(&stream_map); 313 } 314 315 static void apple_dart_domain_flush_tlb(struct apple_dart_domain *domain) 316 { 317 int i; 318 struct apple_dart_atomic_stream_map *domain_stream_map; 319 struct apple_dart_stream_map stream_map; 320 321 for_each_stream_map(i, domain, domain_stream_map) { 322 stream_map.dart = domain_stream_map->dart; 323 stream_map.sidmap = atomic64_read(&domain_stream_map->sidmap); 324 apple_dart_hw_invalidate_tlb(&stream_map); 325 } 326 } 327 328 static void apple_dart_flush_iotlb_all(struct iommu_domain *domain) 329 { 330 apple_dart_domain_flush_tlb(to_dart_domain(domain)); 331 } 332 333 static void apple_dart_iotlb_sync(struct iommu_domain *domain, 334 struct iommu_iotlb_gather *gather) 335 { 336 apple_dart_domain_flush_tlb(to_dart_domain(domain)); 337 } 338 339 static void apple_dart_iotlb_sync_map(struct iommu_domain *domain, 340 unsigned long iova, size_t size) 341 { 342 apple_dart_domain_flush_tlb(to_dart_domain(domain)); 343 } 344 345 static phys_addr_t apple_dart_iova_to_phys(struct iommu_domain *domain, 346 dma_addr_t iova) 347 { 348 struct apple_dart_domain *dart_domain = to_dart_domain(domain); 349 struct io_pgtable_ops *ops = dart_domain->pgtbl_ops; 350 351 if (!ops) 352 return 0; 353 354 return ops->iova_to_phys(ops, iova); 355 } 356 357 static int apple_dart_map_pages(struct iommu_domain *domain, unsigned long iova, 358 phys_addr_t paddr, size_t pgsize, 359 size_t pgcount, int prot, gfp_t gfp, 360 size_t *mapped) 361 { 362 struct apple_dart_domain *dart_domain = to_dart_domain(domain); 363 struct io_pgtable_ops *ops = dart_domain->pgtbl_ops; 364 365 if (!ops) 366 return -ENODEV; 367 368 return ops->map_pages(ops, iova, paddr, pgsize, pgcount, prot, gfp, 369 mapped); 370 } 371 372 static size_t apple_dart_unmap_pages(struct iommu_domain *domain, 373 unsigned long iova, size_t pgsize, 374 size_t pgcount, 375 struct iommu_iotlb_gather *gather) 376 { 377 struct apple_dart_domain *dart_domain = to_dart_domain(domain); 378 struct io_pgtable_ops *ops = dart_domain->pgtbl_ops; 379 380 return ops->unmap_pages(ops, iova, pgsize, pgcount, gather); 381 } 382 383 static void 384 apple_dart_setup_translation(struct apple_dart_domain *domain, 385 struct apple_dart_stream_map *stream_map) 386 { 387 int i; 388 struct io_pgtable_cfg *pgtbl_cfg = 389 &io_pgtable_ops_to_pgtable(domain->pgtbl_ops)->cfg; 390 391 for (i = 0; i < pgtbl_cfg->apple_dart_cfg.n_ttbrs; ++i) 392 apple_dart_hw_set_ttbr(stream_map, i, 393 pgtbl_cfg->apple_dart_cfg.ttbr[i]); 394 for (; i < DART_MAX_TTBR; ++i) 395 apple_dart_hw_clear_ttbr(stream_map, i); 396 397 apple_dart_hw_enable_translation(stream_map); 398 apple_dart_hw_invalidate_tlb(stream_map); 399 } 400 401 static int apple_dart_finalize_domain(struct iommu_domain *domain, 402 struct apple_dart_master_cfg *cfg) 403 { 404 struct apple_dart_domain *dart_domain = to_dart_domain(domain); 405 struct apple_dart *dart = cfg->stream_maps[0].dart; 406 struct io_pgtable_cfg pgtbl_cfg; 407 int ret = 0; 408 int i; 409 410 mutex_lock(&dart_domain->init_lock); 411 412 if (dart_domain->finalized) 413 goto done; 414 415 for (i = 0; i < MAX_DARTS_PER_DEVICE; ++i) { 416 dart_domain->stream_maps[i].dart = cfg->stream_maps[i].dart; 417 atomic64_set(&dart_domain->stream_maps[i].sidmap, 418 cfg->stream_maps[i].sidmap); 419 } 420 421 pgtbl_cfg = (struct io_pgtable_cfg){ 422 .pgsize_bitmap = dart->pgsize, 423 .ias = 32, 424 .oas = 36, 425 .coherent_walk = 1, 426 .iommu_dev = dart->dev, 427 }; 428 429 dart_domain->pgtbl_ops = 430 alloc_io_pgtable_ops(APPLE_DART, &pgtbl_cfg, domain); 431 if (!dart_domain->pgtbl_ops) { 432 ret = -ENOMEM; 433 goto done; 434 } 435 436 domain->pgsize_bitmap = pgtbl_cfg.pgsize_bitmap; 437 domain->geometry.aperture_start = 0; 438 domain->geometry.aperture_end = DMA_BIT_MASK(32); 439 domain->geometry.force_aperture = true; 440 441 dart_domain->finalized = true; 442 443 done: 444 mutex_unlock(&dart_domain->init_lock); 445 return ret; 446 } 447 448 static int 449 apple_dart_mod_streams(struct apple_dart_atomic_stream_map *domain_maps, 450 struct apple_dart_stream_map *master_maps, 451 bool add_streams) 452 { 453 int i; 454 455 for (i = 0; i < MAX_DARTS_PER_DEVICE; ++i) { 456 if (domain_maps[i].dart != master_maps[i].dart) 457 return -EINVAL; 458 } 459 460 for (i = 0; i < MAX_DARTS_PER_DEVICE; ++i) { 461 if (!domain_maps[i].dart) 462 break; 463 if (add_streams) 464 atomic64_or(master_maps[i].sidmap, 465 &domain_maps[i].sidmap); 466 else 467 atomic64_and(~master_maps[i].sidmap, 468 &domain_maps[i].sidmap); 469 } 470 471 return 0; 472 } 473 474 static int apple_dart_domain_add_streams(struct apple_dart_domain *domain, 475 struct apple_dart_master_cfg *cfg) 476 { 477 return apple_dart_mod_streams(domain->stream_maps, cfg->stream_maps, 478 true); 479 } 480 481 static int apple_dart_domain_remove_streams(struct apple_dart_domain *domain, 482 struct apple_dart_master_cfg *cfg) 483 { 484 return apple_dart_mod_streams(domain->stream_maps, cfg->stream_maps, 485 false); 486 } 487 488 static int apple_dart_attach_dev(struct iommu_domain *domain, 489 struct device *dev) 490 { 491 int ret, i; 492 struct apple_dart_stream_map *stream_map; 493 struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev); 494 struct apple_dart_domain *dart_domain = to_dart_domain(domain); 495 496 if (cfg->stream_maps[0].dart->force_bypass && 497 domain->type != IOMMU_DOMAIN_IDENTITY) 498 return -EINVAL; 499 if (!cfg->stream_maps[0].dart->supports_bypass && 500 domain->type == IOMMU_DOMAIN_IDENTITY) 501 return -EINVAL; 502 503 ret = apple_dart_finalize_domain(domain, cfg); 504 if (ret) 505 return ret; 506 507 switch (domain->type) { 508 case IOMMU_DOMAIN_DMA: 509 case IOMMU_DOMAIN_UNMANAGED: 510 ret = apple_dart_domain_add_streams(dart_domain, cfg); 511 if (ret) 512 return ret; 513 514 for_each_stream_map(i, cfg, stream_map) 515 apple_dart_setup_translation(dart_domain, stream_map); 516 break; 517 case IOMMU_DOMAIN_BLOCKED: 518 for_each_stream_map(i, cfg, stream_map) 519 apple_dart_hw_disable_dma(stream_map); 520 break; 521 case IOMMU_DOMAIN_IDENTITY: 522 for_each_stream_map(i, cfg, stream_map) 523 apple_dart_hw_enable_bypass(stream_map); 524 break; 525 } 526 527 return ret; 528 } 529 530 static void apple_dart_detach_dev(struct iommu_domain *domain, 531 struct device *dev) 532 { 533 int i; 534 struct apple_dart_stream_map *stream_map; 535 struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev); 536 struct apple_dart_domain *dart_domain = to_dart_domain(domain); 537 538 for_each_stream_map(i, cfg, stream_map) 539 apple_dart_hw_disable_dma(stream_map); 540 541 if (domain->type == IOMMU_DOMAIN_DMA || 542 domain->type == IOMMU_DOMAIN_UNMANAGED) 543 apple_dart_domain_remove_streams(dart_domain, cfg); 544 } 545 546 static struct iommu_device *apple_dart_probe_device(struct device *dev) 547 { 548 struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev); 549 struct apple_dart_stream_map *stream_map; 550 int i; 551 552 if (!cfg) 553 return ERR_PTR(-ENODEV); 554 555 for_each_stream_map(i, cfg, stream_map) 556 device_link_add( 557 dev, stream_map->dart->dev, 558 DL_FLAG_PM_RUNTIME | DL_FLAG_AUTOREMOVE_SUPPLIER); 559 560 return &cfg->stream_maps[0].dart->iommu; 561 } 562 563 static void apple_dart_release_device(struct device *dev) 564 { 565 struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev); 566 567 dev_iommu_priv_set(dev, NULL); 568 kfree(cfg); 569 } 570 571 static struct iommu_domain *apple_dart_domain_alloc(unsigned int type) 572 { 573 struct apple_dart_domain *dart_domain; 574 575 if (type != IOMMU_DOMAIN_DMA && type != IOMMU_DOMAIN_UNMANAGED && 576 type != IOMMU_DOMAIN_IDENTITY && type != IOMMU_DOMAIN_BLOCKED) 577 return NULL; 578 579 dart_domain = kzalloc(sizeof(*dart_domain), GFP_KERNEL); 580 if (!dart_domain) 581 return NULL; 582 583 mutex_init(&dart_domain->init_lock); 584 585 /* no need to allocate pgtbl_ops or do any other finalization steps */ 586 if (type == IOMMU_DOMAIN_IDENTITY || type == IOMMU_DOMAIN_BLOCKED) 587 dart_domain->finalized = true; 588 589 return &dart_domain->domain; 590 } 591 592 static void apple_dart_domain_free(struct iommu_domain *domain) 593 { 594 struct apple_dart_domain *dart_domain = to_dart_domain(domain); 595 596 if (dart_domain->pgtbl_ops) 597 free_io_pgtable_ops(dart_domain->pgtbl_ops); 598 599 kfree(dart_domain); 600 } 601 602 static int apple_dart_of_xlate(struct device *dev, struct of_phandle_args *args) 603 { 604 struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev); 605 struct platform_device *iommu_pdev = of_find_device_by_node(args->np); 606 struct apple_dart *dart = platform_get_drvdata(iommu_pdev); 607 struct apple_dart *cfg_dart; 608 int i, sid; 609 610 if (args->args_count != 1) 611 return -EINVAL; 612 sid = args->args[0]; 613 614 if (!cfg) 615 cfg = kzalloc(sizeof(*cfg), GFP_KERNEL); 616 if (!cfg) 617 return -ENOMEM; 618 dev_iommu_priv_set(dev, cfg); 619 620 cfg_dart = cfg->stream_maps[0].dart; 621 if (cfg_dart) { 622 if (cfg_dart->supports_bypass != dart->supports_bypass) 623 return -EINVAL; 624 if (cfg_dart->force_bypass != dart->force_bypass) 625 return -EINVAL; 626 if (cfg_dart->pgsize != dart->pgsize) 627 return -EINVAL; 628 } 629 630 for (i = 0; i < MAX_DARTS_PER_DEVICE; ++i) { 631 if (cfg->stream_maps[i].dart == dart) { 632 cfg->stream_maps[i].sidmap |= 1 << sid; 633 return 0; 634 } 635 } 636 for (i = 0; i < MAX_DARTS_PER_DEVICE; ++i) { 637 if (!cfg->stream_maps[i].dart) { 638 cfg->stream_maps[i].dart = dart; 639 cfg->stream_maps[i].sidmap = 1 << sid; 640 return 0; 641 } 642 } 643 644 return -EINVAL; 645 } 646 647 static DEFINE_MUTEX(apple_dart_groups_lock); 648 649 static void apple_dart_release_group(void *iommu_data) 650 { 651 int i, sid; 652 struct apple_dart_stream_map *stream_map; 653 struct apple_dart_master_cfg *group_master_cfg = iommu_data; 654 655 mutex_lock(&apple_dart_groups_lock); 656 657 for_each_stream_map(i, group_master_cfg, stream_map) 658 for_each_set_bit(sid, &stream_map->sidmap, DART_MAX_STREAMS) 659 stream_map->dart->sid2group[sid] = NULL; 660 661 kfree(iommu_data); 662 mutex_unlock(&apple_dart_groups_lock); 663 } 664 665 static struct iommu_group *apple_dart_device_group(struct device *dev) 666 { 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 apple_dart_master_cfg *group_master_cfg; 671 struct iommu_group *group = NULL; 672 struct iommu_group *res = ERR_PTR(-EINVAL); 673 674 mutex_lock(&apple_dart_groups_lock); 675 676 for_each_stream_map(i, cfg, stream_map) { 677 for_each_set_bit(sid, &stream_map->sidmap, DART_MAX_STREAMS) { 678 struct iommu_group *stream_group = 679 stream_map->dart->sid2group[sid]; 680 681 if (group && group != stream_group) { 682 res = ERR_PTR(-EINVAL); 683 goto out; 684 } 685 686 group = stream_group; 687 } 688 } 689 690 if (group) { 691 res = iommu_group_ref_get(group); 692 goto out; 693 } 694 695 #ifdef CONFIG_PCI 696 if (dev_is_pci(dev)) 697 group = pci_device_group(dev); 698 else 699 #endif 700 group = generic_device_group(dev); 701 702 res = ERR_PTR(-ENOMEM); 703 if (!group) 704 goto out; 705 706 group_master_cfg = kmemdup(cfg, sizeof(*group_master_cfg), GFP_KERNEL); 707 if (!group_master_cfg) { 708 iommu_group_put(group); 709 goto out; 710 } 711 712 iommu_group_set_iommudata(group, group_master_cfg, 713 apple_dart_release_group); 714 715 for_each_stream_map(i, cfg, stream_map) 716 for_each_set_bit(sid, &stream_map->sidmap, DART_MAX_STREAMS) 717 stream_map->dart->sid2group[sid] = group; 718 719 res = group; 720 721 out: 722 mutex_unlock(&apple_dart_groups_lock); 723 return res; 724 } 725 726 static int apple_dart_def_domain_type(struct device *dev) 727 { 728 struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev); 729 730 if (cfg->stream_maps[0].dart->force_bypass) 731 return IOMMU_DOMAIN_IDENTITY; 732 if (!cfg->stream_maps[0].dart->supports_bypass) 733 return IOMMU_DOMAIN_DMA; 734 735 return 0; 736 } 737 738 #ifndef CONFIG_PCIE_APPLE_MSI_DOORBELL_ADDR 739 /* Keep things compiling when CONFIG_PCI_APPLE isn't selected */ 740 #define CONFIG_PCIE_APPLE_MSI_DOORBELL_ADDR 0 741 #endif 742 #define DOORBELL_ADDR (CONFIG_PCIE_APPLE_MSI_DOORBELL_ADDR & PAGE_MASK) 743 744 static void apple_dart_get_resv_regions(struct device *dev, 745 struct list_head *head) 746 { 747 if (IS_ENABLED(CONFIG_PCIE_APPLE) && dev_is_pci(dev)) { 748 struct iommu_resv_region *region; 749 int prot = IOMMU_WRITE | IOMMU_NOEXEC | IOMMU_MMIO; 750 751 region = iommu_alloc_resv_region(DOORBELL_ADDR, 752 PAGE_SIZE, prot, 753 IOMMU_RESV_MSI); 754 if (!region) 755 return; 756 757 list_add_tail(®ion->list, head); 758 } 759 760 iommu_dma_get_resv_regions(dev, head); 761 } 762 763 static const struct iommu_ops apple_dart_iommu_ops = { 764 .domain_alloc = apple_dart_domain_alloc, 765 .probe_device = apple_dart_probe_device, 766 .release_device = apple_dart_release_device, 767 .device_group = apple_dart_device_group, 768 .of_xlate = apple_dart_of_xlate, 769 .def_domain_type = apple_dart_def_domain_type, 770 .get_resv_regions = apple_dart_get_resv_regions, 771 .pgsize_bitmap = -1UL, /* Restricted during dart probe */ 772 .owner = THIS_MODULE, 773 .default_domain_ops = &(const struct iommu_domain_ops) { 774 .attach_dev = apple_dart_attach_dev, 775 .detach_dev = apple_dart_detach_dev, 776 .map_pages = apple_dart_map_pages, 777 .unmap_pages = apple_dart_unmap_pages, 778 .flush_iotlb_all = apple_dart_flush_iotlb_all, 779 .iotlb_sync = apple_dart_iotlb_sync, 780 .iotlb_sync_map = apple_dart_iotlb_sync_map, 781 .iova_to_phys = apple_dart_iova_to_phys, 782 .free = apple_dart_domain_free, 783 } 784 }; 785 786 static irqreturn_t apple_dart_irq(int irq, void *dev) 787 { 788 struct apple_dart *dart = dev; 789 const char *fault_name = NULL; 790 u32 error = readl(dart->regs + DART_ERROR); 791 u32 error_code = FIELD_GET(DART_ERROR_CODE, error); 792 u32 addr_lo = readl(dart->regs + DART_ERROR_ADDR_LO); 793 u32 addr_hi = readl(dart->regs + DART_ERROR_ADDR_HI); 794 u64 addr = addr_lo | (((u64)addr_hi) << 32); 795 u8 stream_idx = FIELD_GET(DART_ERROR_STREAM, error); 796 797 if (!(error & DART_ERROR_FLAG)) 798 return IRQ_NONE; 799 800 /* there should only be a single bit set but let's use == to be sure */ 801 if (error_code == DART_ERROR_READ_FAULT) 802 fault_name = "READ FAULT"; 803 else if (error_code == DART_ERROR_WRITE_FAULT) 804 fault_name = "WRITE FAULT"; 805 else if (error_code == DART_ERROR_NO_PTE) 806 fault_name = "NO PTE FOR IOVA"; 807 else if (error_code == DART_ERROR_NO_PMD) 808 fault_name = "NO PMD FOR IOVA"; 809 else if (error_code == DART_ERROR_NO_TTBR) 810 fault_name = "NO TTBR FOR IOVA"; 811 else 812 fault_name = "unknown"; 813 814 dev_err_ratelimited( 815 dart->dev, 816 "translation fault: status:0x%x stream:%d code:0x%x (%s) at 0x%llx", 817 error, stream_idx, error_code, fault_name, addr); 818 819 writel(error, dart->regs + DART_ERROR); 820 return IRQ_HANDLED; 821 } 822 823 static int apple_dart_set_bus_ops(const struct iommu_ops *ops) 824 { 825 int ret; 826 827 if (!iommu_present(&platform_bus_type)) { 828 ret = bus_set_iommu(&platform_bus_type, ops); 829 if (ret) 830 return ret; 831 } 832 #ifdef CONFIG_PCI 833 if (!iommu_present(&pci_bus_type)) { 834 ret = bus_set_iommu(&pci_bus_type, ops); 835 if (ret) { 836 bus_set_iommu(&platform_bus_type, NULL); 837 return ret; 838 } 839 } 840 #endif 841 return 0; 842 } 843 844 static int apple_dart_probe(struct platform_device *pdev) 845 { 846 int ret; 847 u32 dart_params[2]; 848 struct resource *res; 849 struct apple_dart *dart; 850 struct device *dev = &pdev->dev; 851 852 dart = devm_kzalloc(dev, sizeof(*dart), GFP_KERNEL); 853 if (!dart) 854 return -ENOMEM; 855 856 dart->dev = dev; 857 spin_lock_init(&dart->lock); 858 859 dart->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res); 860 if (IS_ERR(dart->regs)) 861 return PTR_ERR(dart->regs); 862 863 if (resource_size(res) < 0x4000) { 864 dev_err(dev, "MMIO region too small (%pr)\n", res); 865 return -EINVAL; 866 } 867 868 dart->irq = platform_get_irq(pdev, 0); 869 if (dart->irq < 0) 870 return -ENODEV; 871 872 ret = devm_clk_bulk_get_all(dev, &dart->clks); 873 if (ret < 0) 874 return ret; 875 dart->num_clks = ret; 876 877 ret = clk_bulk_prepare_enable(dart->num_clks, dart->clks); 878 if (ret) 879 return ret; 880 881 ret = apple_dart_hw_reset(dart); 882 if (ret) 883 goto err_clk_disable; 884 885 dart_params[0] = readl(dart->regs + DART_PARAMS1); 886 dart_params[1] = readl(dart->regs + DART_PARAMS2); 887 dart->pgsize = 1 << FIELD_GET(DART_PARAMS_PAGE_SHIFT, dart_params[0]); 888 dart->supports_bypass = dart_params[1] & DART_PARAMS_BYPASS_SUPPORT; 889 dart->force_bypass = dart->pgsize > PAGE_SIZE; 890 891 ret = request_irq(dart->irq, apple_dart_irq, IRQF_SHARED, 892 "apple-dart fault handler", dart); 893 if (ret) 894 goto err_clk_disable; 895 896 platform_set_drvdata(pdev, dart); 897 898 ret = apple_dart_set_bus_ops(&apple_dart_iommu_ops); 899 if (ret) 900 goto err_free_irq; 901 902 ret = iommu_device_sysfs_add(&dart->iommu, dev, NULL, "apple-dart.%s", 903 dev_name(&pdev->dev)); 904 if (ret) 905 goto err_remove_bus_ops; 906 907 ret = iommu_device_register(&dart->iommu, &apple_dart_iommu_ops, dev); 908 if (ret) 909 goto err_sysfs_remove; 910 911 dev_info( 912 &pdev->dev, 913 "DART [pagesize %x, bypass support: %d, bypass forced: %d] initialized\n", 914 dart->pgsize, dart->supports_bypass, dart->force_bypass); 915 return 0; 916 917 err_sysfs_remove: 918 iommu_device_sysfs_remove(&dart->iommu); 919 err_remove_bus_ops: 920 apple_dart_set_bus_ops(NULL); 921 err_free_irq: 922 free_irq(dart->irq, dart); 923 err_clk_disable: 924 clk_bulk_disable_unprepare(dart->num_clks, dart->clks); 925 926 return ret; 927 } 928 929 static int apple_dart_remove(struct platform_device *pdev) 930 { 931 struct apple_dart *dart = platform_get_drvdata(pdev); 932 933 apple_dart_hw_reset(dart); 934 free_irq(dart->irq, dart); 935 apple_dart_set_bus_ops(NULL); 936 937 iommu_device_unregister(&dart->iommu); 938 iommu_device_sysfs_remove(&dart->iommu); 939 940 clk_bulk_disable_unprepare(dart->num_clks, dart->clks); 941 942 return 0; 943 } 944 945 static const struct of_device_id apple_dart_of_match[] = { 946 { .compatible = "apple,t8103-dart", .data = NULL }, 947 {}, 948 }; 949 MODULE_DEVICE_TABLE(of, apple_dart_of_match); 950 951 static struct platform_driver apple_dart_driver = { 952 .driver = { 953 .name = "apple-dart", 954 .of_match_table = apple_dart_of_match, 955 .suppress_bind_attrs = true, 956 }, 957 .probe = apple_dart_probe, 958 .remove = apple_dart_remove, 959 }; 960 961 module_platform_driver(apple_dart_driver); 962 963 MODULE_DESCRIPTION("IOMMU API for Apple's DART"); 964 MODULE_AUTHOR("Sven Peter <sven@svenpeter.dev>"); 965 MODULE_LICENSE("GPL v2"); 966