1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * IOMMU API for Renesas VMSA-compatible IPMMU 4 * Author: Laurent Pinchart <laurent.pinchart@ideasonboard.com> 5 * 6 * Copyright (C) 2014-2020 Renesas Electronics Corporation 7 */ 8 9 #include <linux/bitmap.h> 10 #include <linux/delay.h> 11 #include <linux/dma-mapping.h> 12 #include <linux/err.h> 13 #include <linux/export.h> 14 #include <linux/init.h> 15 #include <linux/interrupt.h> 16 #include <linux/io.h> 17 #include <linux/iopoll.h> 18 #include <linux/io-pgtable.h> 19 #include <linux/iommu.h> 20 #include <linux/of.h> 21 #include <linux/of_platform.h> 22 #include <linux/pci.h> 23 #include <linux/platform_device.h> 24 #include <linux/sizes.h> 25 #include <linux/slab.h> 26 #include <linux/sys_soc.h> 27 28 #if defined(CONFIG_ARM) && !defined(CONFIG_IOMMU_DMA) 29 #include <asm/dma-iommu.h> 30 #else 31 #define arm_iommu_create_mapping(...) NULL 32 #define arm_iommu_attach_device(...) -ENODEV 33 #define arm_iommu_release_mapping(...) do {} while (0) 34 #endif 35 36 #define IPMMU_CTX_MAX 16U 37 #define IPMMU_CTX_INVALID -1 38 39 #define IPMMU_UTLB_MAX 64U 40 41 struct ipmmu_features { 42 bool use_ns_alias_offset; 43 bool has_cache_leaf_nodes; 44 unsigned int number_of_contexts; 45 unsigned int num_utlbs; 46 bool setup_imbuscr; 47 bool twobit_imttbcr_sl0; 48 bool reserved_context; 49 bool cache_snoop; 50 unsigned int ctx_offset_base; 51 unsigned int ctx_offset_stride; 52 unsigned int utlb_offset_base; 53 }; 54 55 struct ipmmu_vmsa_device { 56 struct device *dev; 57 void __iomem *base; 58 struct iommu_device iommu; 59 struct ipmmu_vmsa_device *root; 60 const struct ipmmu_features *features; 61 unsigned int num_ctx; 62 spinlock_t lock; /* Protects ctx and domains[] */ 63 DECLARE_BITMAP(ctx, IPMMU_CTX_MAX); 64 struct ipmmu_vmsa_domain *domains[IPMMU_CTX_MAX]; 65 s8 utlb_ctx[IPMMU_UTLB_MAX]; 66 67 struct dma_iommu_mapping *mapping; 68 }; 69 70 struct ipmmu_vmsa_domain { 71 struct ipmmu_vmsa_device *mmu; 72 struct iommu_domain io_domain; 73 74 struct io_pgtable_cfg cfg; 75 struct io_pgtable_ops *iop; 76 77 unsigned int context_id; 78 struct mutex mutex; /* Protects mappings */ 79 }; 80 81 static struct ipmmu_vmsa_domain *to_vmsa_domain(struct iommu_domain *dom) 82 { 83 return container_of(dom, struct ipmmu_vmsa_domain, io_domain); 84 } 85 86 static struct ipmmu_vmsa_device *to_ipmmu(struct device *dev) 87 { 88 return dev_iommu_priv_get(dev); 89 } 90 91 #define TLB_LOOP_TIMEOUT 100 /* 100us */ 92 93 /* ----------------------------------------------------------------------------- 94 * Registers Definition 95 */ 96 97 #define IM_NS_ALIAS_OFFSET 0x800 98 99 /* MMU "context" registers */ 100 #define IMCTR 0x0000 /* R-Car Gen2/3 */ 101 #define IMCTR_INTEN (1 << 2) /* R-Car Gen2/3 */ 102 #define IMCTR_FLUSH (1 << 1) /* R-Car Gen2/3 */ 103 #define IMCTR_MMUEN (1 << 0) /* R-Car Gen2/3 */ 104 105 #define IMTTBCR 0x0008 /* R-Car Gen2/3 */ 106 #define IMTTBCR_EAE (1 << 31) /* R-Car Gen2/3 */ 107 #define IMTTBCR_SH0_INNER_SHAREABLE (3 << 12) /* R-Car Gen2 only */ 108 #define IMTTBCR_ORGN0_WB_WA (1 << 10) /* R-Car Gen2 only */ 109 #define IMTTBCR_IRGN0_WB_WA (1 << 8) /* R-Car Gen2 only */ 110 #define IMTTBCR_SL0_TWOBIT_LVL_1 (2 << 6) /* R-Car Gen3 only */ 111 #define IMTTBCR_SL0_LVL_1 (1 << 4) /* R-Car Gen2 only */ 112 113 #define IMBUSCR 0x000c /* R-Car Gen2 only */ 114 #define IMBUSCR_DVM (1 << 2) /* R-Car Gen2 only */ 115 #define IMBUSCR_BUSSEL_MASK (3 << 0) /* R-Car Gen2 only */ 116 117 #define IMTTLBR0 0x0010 /* R-Car Gen2/3 */ 118 #define IMTTUBR0 0x0014 /* R-Car Gen2/3 */ 119 120 #define IMSTR 0x0020 /* R-Car Gen2/3 */ 121 #define IMSTR_MHIT (1 << 4) /* R-Car Gen2/3 */ 122 #define IMSTR_ABORT (1 << 2) /* R-Car Gen2/3 */ 123 #define IMSTR_PF (1 << 1) /* R-Car Gen2/3 */ 124 #define IMSTR_TF (1 << 0) /* R-Car Gen2/3 */ 125 126 #define IMMAIR0 0x0028 /* R-Car Gen2/3 */ 127 128 #define IMELAR 0x0030 /* R-Car Gen2/3, IMEAR on R-Car Gen2 */ 129 #define IMEUAR 0x0034 /* R-Car Gen3 only */ 130 131 /* uTLB registers */ 132 #define IMUCTR(n) ((n) < 32 ? IMUCTR0(n) : IMUCTR32(n)) 133 #define IMUCTR0(n) (0x0300 + ((n) * 16)) /* R-Car Gen2/3 */ 134 #define IMUCTR32(n) (0x0600 + (((n) - 32) * 16)) /* R-Car Gen3 only */ 135 #define IMUCTR_TTSEL_MMU(n) ((n) << 4) /* R-Car Gen2/3 */ 136 #define IMUCTR_FLUSH (1 << 1) /* R-Car Gen2/3 */ 137 #define IMUCTR_MMUEN (1 << 0) /* R-Car Gen2/3 */ 138 139 #define IMUASID(n) ((n) < 32 ? IMUASID0(n) : IMUASID32(n)) 140 #define IMUASID0(n) (0x0308 + ((n) * 16)) /* R-Car Gen2/3 */ 141 #define IMUASID32(n) (0x0608 + (((n) - 32) * 16)) /* R-Car Gen3 only */ 142 143 /* ----------------------------------------------------------------------------- 144 * Root device handling 145 */ 146 147 static struct platform_driver ipmmu_driver; 148 149 static bool ipmmu_is_root(struct ipmmu_vmsa_device *mmu) 150 { 151 return mmu->root == mmu; 152 } 153 154 static int __ipmmu_check_device(struct device *dev, void *data) 155 { 156 struct ipmmu_vmsa_device *mmu = dev_get_drvdata(dev); 157 struct ipmmu_vmsa_device **rootp = data; 158 159 if (ipmmu_is_root(mmu)) 160 *rootp = mmu; 161 162 return 0; 163 } 164 165 static struct ipmmu_vmsa_device *ipmmu_find_root(void) 166 { 167 struct ipmmu_vmsa_device *root = NULL; 168 169 return driver_for_each_device(&ipmmu_driver.driver, NULL, &root, 170 __ipmmu_check_device) == 0 ? root : NULL; 171 } 172 173 /* ----------------------------------------------------------------------------- 174 * Read/Write Access 175 */ 176 177 static u32 ipmmu_read(struct ipmmu_vmsa_device *mmu, unsigned int offset) 178 { 179 return ioread32(mmu->base + offset); 180 } 181 182 static void ipmmu_write(struct ipmmu_vmsa_device *mmu, unsigned int offset, 183 u32 data) 184 { 185 iowrite32(data, mmu->base + offset); 186 } 187 188 static unsigned int ipmmu_ctx_reg(struct ipmmu_vmsa_device *mmu, 189 unsigned int context_id, unsigned int reg) 190 { 191 unsigned int base = mmu->features->ctx_offset_base; 192 193 if (context_id > 7) 194 base += 0x800 - 8 * 0x40; 195 196 return base + context_id * mmu->features->ctx_offset_stride + reg; 197 } 198 199 static u32 ipmmu_ctx_read(struct ipmmu_vmsa_device *mmu, 200 unsigned int context_id, unsigned int reg) 201 { 202 return ipmmu_read(mmu, ipmmu_ctx_reg(mmu, context_id, reg)); 203 } 204 205 static void ipmmu_ctx_write(struct ipmmu_vmsa_device *mmu, 206 unsigned int context_id, unsigned int reg, u32 data) 207 { 208 ipmmu_write(mmu, ipmmu_ctx_reg(mmu, context_id, reg), data); 209 } 210 211 static u32 ipmmu_ctx_read_root(struct ipmmu_vmsa_domain *domain, 212 unsigned int reg) 213 { 214 return ipmmu_ctx_read(domain->mmu->root, domain->context_id, reg); 215 } 216 217 static void ipmmu_ctx_write_root(struct ipmmu_vmsa_domain *domain, 218 unsigned int reg, u32 data) 219 { 220 ipmmu_ctx_write(domain->mmu->root, domain->context_id, reg, data); 221 } 222 223 static void ipmmu_ctx_write_all(struct ipmmu_vmsa_domain *domain, 224 unsigned int reg, u32 data) 225 { 226 if (domain->mmu != domain->mmu->root) 227 ipmmu_ctx_write(domain->mmu, domain->context_id, reg, data); 228 229 ipmmu_ctx_write(domain->mmu->root, domain->context_id, reg, data); 230 } 231 232 static u32 ipmmu_utlb_reg(struct ipmmu_vmsa_device *mmu, unsigned int reg) 233 { 234 return mmu->features->utlb_offset_base + reg; 235 } 236 237 static void ipmmu_imuasid_write(struct ipmmu_vmsa_device *mmu, 238 unsigned int utlb, u32 data) 239 { 240 ipmmu_write(mmu, ipmmu_utlb_reg(mmu, IMUASID(utlb)), data); 241 } 242 243 static void ipmmu_imuctr_write(struct ipmmu_vmsa_device *mmu, 244 unsigned int utlb, u32 data) 245 { 246 ipmmu_write(mmu, ipmmu_utlb_reg(mmu, IMUCTR(utlb)), data); 247 } 248 249 /* ----------------------------------------------------------------------------- 250 * TLB and microTLB Management 251 */ 252 253 /* Wait for any pending TLB invalidations to complete */ 254 static void ipmmu_tlb_sync(struct ipmmu_vmsa_domain *domain) 255 { 256 u32 val; 257 258 if (read_poll_timeout_atomic(ipmmu_ctx_read_root, val, 259 !(val & IMCTR_FLUSH), 1, TLB_LOOP_TIMEOUT, 260 false, domain, IMCTR)) 261 dev_err_ratelimited(domain->mmu->dev, 262 "TLB sync timed out -- MMU may be deadlocked\n"); 263 } 264 265 static void ipmmu_tlb_invalidate(struct ipmmu_vmsa_domain *domain) 266 { 267 u32 reg; 268 269 reg = ipmmu_ctx_read_root(domain, IMCTR); 270 reg |= IMCTR_FLUSH; 271 ipmmu_ctx_write_all(domain, IMCTR, reg); 272 273 ipmmu_tlb_sync(domain); 274 } 275 276 /* 277 * Enable MMU translation for the microTLB. 278 */ 279 static void ipmmu_utlb_enable(struct ipmmu_vmsa_domain *domain, 280 unsigned int utlb) 281 { 282 struct ipmmu_vmsa_device *mmu = domain->mmu; 283 284 /* 285 * TODO: Reference-count the microTLB as several bus masters can be 286 * connected to the same microTLB. 287 */ 288 289 /* TODO: What should we set the ASID to ? */ 290 ipmmu_imuasid_write(mmu, utlb, 0); 291 /* TODO: Do we need to flush the microTLB ? */ 292 ipmmu_imuctr_write(mmu, utlb, IMUCTR_TTSEL_MMU(domain->context_id) | 293 IMUCTR_FLUSH | IMUCTR_MMUEN); 294 mmu->utlb_ctx[utlb] = domain->context_id; 295 } 296 297 /* 298 * Disable MMU translation for the microTLB. 299 */ 300 static void ipmmu_utlb_disable(struct ipmmu_vmsa_domain *domain, 301 unsigned int utlb) 302 { 303 struct ipmmu_vmsa_device *mmu = domain->mmu; 304 305 ipmmu_imuctr_write(mmu, utlb, 0); 306 mmu->utlb_ctx[utlb] = IPMMU_CTX_INVALID; 307 } 308 309 static void ipmmu_tlb_flush_all(void *cookie) 310 { 311 struct ipmmu_vmsa_domain *domain = cookie; 312 313 ipmmu_tlb_invalidate(domain); 314 } 315 316 static void ipmmu_tlb_flush(unsigned long iova, size_t size, 317 size_t granule, void *cookie) 318 { 319 ipmmu_tlb_flush_all(cookie); 320 } 321 322 static const struct iommu_flush_ops ipmmu_flush_ops = { 323 .tlb_flush_all = ipmmu_tlb_flush_all, 324 .tlb_flush_walk = ipmmu_tlb_flush, 325 }; 326 327 /* ----------------------------------------------------------------------------- 328 * Domain/Context Management 329 */ 330 331 static int ipmmu_domain_allocate_context(struct ipmmu_vmsa_device *mmu, 332 struct ipmmu_vmsa_domain *domain) 333 { 334 unsigned long flags; 335 int ret; 336 337 spin_lock_irqsave(&mmu->lock, flags); 338 339 ret = find_first_zero_bit(mmu->ctx, mmu->num_ctx); 340 if (ret != mmu->num_ctx) { 341 mmu->domains[ret] = domain; 342 set_bit(ret, mmu->ctx); 343 } else 344 ret = -EBUSY; 345 346 spin_unlock_irqrestore(&mmu->lock, flags); 347 348 return ret; 349 } 350 351 static void ipmmu_domain_free_context(struct ipmmu_vmsa_device *mmu, 352 unsigned int context_id) 353 { 354 unsigned long flags; 355 356 spin_lock_irqsave(&mmu->lock, flags); 357 358 clear_bit(context_id, mmu->ctx); 359 mmu->domains[context_id] = NULL; 360 361 spin_unlock_irqrestore(&mmu->lock, flags); 362 } 363 364 static void ipmmu_domain_setup_context(struct ipmmu_vmsa_domain *domain) 365 { 366 u64 ttbr; 367 u32 tmp; 368 369 /* TTBR0 */ 370 ttbr = domain->cfg.arm_lpae_s1_cfg.ttbr; 371 ipmmu_ctx_write_root(domain, IMTTLBR0, ttbr); 372 ipmmu_ctx_write_root(domain, IMTTUBR0, ttbr >> 32); 373 374 /* 375 * TTBCR 376 * We use long descriptors and allocate the whole 32-bit VA space to 377 * TTBR0. 378 */ 379 if (domain->mmu->features->twobit_imttbcr_sl0) 380 tmp = IMTTBCR_SL0_TWOBIT_LVL_1; 381 else 382 tmp = IMTTBCR_SL0_LVL_1; 383 384 if (domain->mmu->features->cache_snoop) 385 tmp |= IMTTBCR_SH0_INNER_SHAREABLE | IMTTBCR_ORGN0_WB_WA | 386 IMTTBCR_IRGN0_WB_WA; 387 388 ipmmu_ctx_write_root(domain, IMTTBCR, IMTTBCR_EAE | tmp); 389 390 /* MAIR0 */ 391 ipmmu_ctx_write_root(domain, IMMAIR0, 392 domain->cfg.arm_lpae_s1_cfg.mair); 393 394 /* IMBUSCR */ 395 if (domain->mmu->features->setup_imbuscr) 396 ipmmu_ctx_write_root(domain, IMBUSCR, 397 ipmmu_ctx_read_root(domain, IMBUSCR) & 398 ~(IMBUSCR_DVM | IMBUSCR_BUSSEL_MASK)); 399 400 /* 401 * IMSTR 402 * Clear all interrupt flags. 403 */ 404 ipmmu_ctx_write_root(domain, IMSTR, ipmmu_ctx_read_root(domain, IMSTR)); 405 406 /* 407 * IMCTR 408 * Enable the MMU and interrupt generation. The long-descriptor 409 * translation table format doesn't use TEX remapping. Don't enable AF 410 * software management as we have no use for it. Flush the TLB as 411 * required when modifying the context registers. 412 */ 413 ipmmu_ctx_write_all(domain, IMCTR, 414 IMCTR_INTEN | IMCTR_FLUSH | IMCTR_MMUEN); 415 } 416 417 static int ipmmu_domain_init_context(struct ipmmu_vmsa_domain *domain) 418 { 419 int ret; 420 421 /* 422 * Allocate the page table operations. 423 * 424 * VMSA states in section B3.6.3 "Control of Secure or Non-secure memory 425 * access, Long-descriptor format" that the NStable bit being set in a 426 * table descriptor will result in the NStable and NS bits of all child 427 * entries being ignored and considered as being set. The IPMMU seems 428 * not to comply with this, as it generates a secure access page fault 429 * if any of the NStable and NS bits isn't set when running in 430 * non-secure mode. 431 */ 432 domain->cfg.quirks = IO_PGTABLE_QUIRK_ARM_NS; 433 domain->cfg.pgsize_bitmap = SZ_1G | SZ_2M | SZ_4K; 434 domain->cfg.ias = 32; 435 domain->cfg.oas = 40; 436 domain->cfg.tlb = &ipmmu_flush_ops; 437 domain->io_domain.geometry.aperture_end = DMA_BIT_MASK(32); 438 domain->io_domain.geometry.force_aperture = true; 439 /* 440 * TODO: Add support for coherent walk through CCI with DVM and remove 441 * cache handling. For now, delegate it to the io-pgtable code. 442 */ 443 domain->cfg.coherent_walk = false; 444 domain->cfg.iommu_dev = domain->mmu->root->dev; 445 446 /* 447 * Find an unused context. 448 */ 449 ret = ipmmu_domain_allocate_context(domain->mmu->root, domain); 450 if (ret < 0) 451 return ret; 452 453 domain->context_id = ret; 454 455 domain->iop = alloc_io_pgtable_ops(ARM_32_LPAE_S1, &domain->cfg, 456 domain); 457 if (!domain->iop) { 458 ipmmu_domain_free_context(domain->mmu->root, 459 domain->context_id); 460 return -EINVAL; 461 } 462 463 ipmmu_domain_setup_context(domain); 464 return 0; 465 } 466 467 static void ipmmu_domain_destroy_context(struct ipmmu_vmsa_domain *domain) 468 { 469 if (!domain->mmu) 470 return; 471 472 /* 473 * Disable the context. Flush the TLB as required when modifying the 474 * context registers. 475 * 476 * TODO: Is TLB flush really needed ? 477 */ 478 ipmmu_ctx_write_all(domain, IMCTR, IMCTR_FLUSH); 479 ipmmu_tlb_sync(domain); 480 ipmmu_domain_free_context(domain->mmu->root, domain->context_id); 481 } 482 483 /* ----------------------------------------------------------------------------- 484 * Fault Handling 485 */ 486 487 static irqreturn_t ipmmu_domain_irq(struct ipmmu_vmsa_domain *domain) 488 { 489 const u32 err_mask = IMSTR_MHIT | IMSTR_ABORT | IMSTR_PF | IMSTR_TF; 490 struct ipmmu_vmsa_device *mmu = domain->mmu; 491 unsigned long iova; 492 u32 status; 493 494 status = ipmmu_ctx_read_root(domain, IMSTR); 495 if (!(status & err_mask)) 496 return IRQ_NONE; 497 498 iova = ipmmu_ctx_read_root(domain, IMELAR); 499 if (IS_ENABLED(CONFIG_64BIT)) 500 iova |= (u64)ipmmu_ctx_read_root(domain, IMEUAR) << 32; 501 502 /* 503 * Clear the error status flags. Unlike traditional interrupt flag 504 * registers that must be cleared by writing 1, this status register 505 * seems to require 0. The error address register must be read before, 506 * otherwise its value will be 0. 507 */ 508 ipmmu_ctx_write_root(domain, IMSTR, 0); 509 510 /* Log fatal errors. */ 511 if (status & IMSTR_MHIT) 512 dev_err_ratelimited(mmu->dev, "Multiple TLB hits @0x%lx\n", 513 iova); 514 if (status & IMSTR_ABORT) 515 dev_err_ratelimited(mmu->dev, "Page Table Walk Abort @0x%lx\n", 516 iova); 517 518 if (!(status & (IMSTR_PF | IMSTR_TF))) 519 return IRQ_NONE; 520 521 /* 522 * Try to handle page faults and translation faults. 523 * 524 * TODO: We need to look up the faulty device based on the I/O VA. Use 525 * the IOMMU device for now. 526 */ 527 if (!report_iommu_fault(&domain->io_domain, mmu->dev, iova, 0)) 528 return IRQ_HANDLED; 529 530 dev_err_ratelimited(mmu->dev, 531 "Unhandled fault: status 0x%08x iova 0x%lx\n", 532 status, iova); 533 534 return IRQ_HANDLED; 535 } 536 537 static irqreturn_t ipmmu_irq(int irq, void *dev) 538 { 539 struct ipmmu_vmsa_device *mmu = dev; 540 irqreturn_t status = IRQ_NONE; 541 unsigned int i; 542 unsigned long flags; 543 544 spin_lock_irqsave(&mmu->lock, flags); 545 546 /* 547 * Check interrupts for all active contexts. 548 */ 549 for (i = 0; i < mmu->num_ctx; i++) { 550 if (!mmu->domains[i]) 551 continue; 552 if (ipmmu_domain_irq(mmu->domains[i]) == IRQ_HANDLED) 553 status = IRQ_HANDLED; 554 } 555 556 spin_unlock_irqrestore(&mmu->lock, flags); 557 558 return status; 559 } 560 561 /* ----------------------------------------------------------------------------- 562 * IOMMU Operations 563 */ 564 565 static struct iommu_domain *ipmmu_domain_alloc_paging(struct device *dev) 566 { 567 struct ipmmu_vmsa_domain *domain; 568 569 domain = kzalloc(sizeof(*domain), GFP_KERNEL); 570 if (!domain) 571 return NULL; 572 573 mutex_init(&domain->mutex); 574 575 return &domain->io_domain; 576 } 577 578 static void ipmmu_domain_free(struct iommu_domain *io_domain) 579 { 580 struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain); 581 582 /* 583 * Free the domain resources. We assume that all devices have already 584 * been detached. 585 */ 586 ipmmu_domain_destroy_context(domain); 587 free_io_pgtable_ops(domain->iop); 588 kfree(domain); 589 } 590 591 static int ipmmu_attach_device(struct iommu_domain *io_domain, 592 struct device *dev) 593 { 594 struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); 595 struct ipmmu_vmsa_device *mmu = to_ipmmu(dev); 596 struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain); 597 unsigned int i; 598 int ret = 0; 599 600 if (!mmu) { 601 dev_err(dev, "Cannot attach to IPMMU\n"); 602 return -ENXIO; 603 } 604 605 mutex_lock(&domain->mutex); 606 607 if (!domain->mmu) { 608 /* The domain hasn't been used yet, initialize it. */ 609 domain->mmu = mmu; 610 ret = ipmmu_domain_init_context(domain); 611 if (ret < 0) { 612 dev_err(dev, "Unable to initialize IPMMU context\n"); 613 domain->mmu = NULL; 614 } else { 615 dev_info(dev, "Using IPMMU context %u\n", 616 domain->context_id); 617 } 618 } else if (domain->mmu != mmu) { 619 /* 620 * Something is wrong, we can't attach two devices using 621 * different IOMMUs to the same domain. 622 */ 623 ret = -EINVAL; 624 } else 625 dev_info(dev, "Reusing IPMMU context %u\n", domain->context_id); 626 627 mutex_unlock(&domain->mutex); 628 629 if (ret < 0) 630 return ret; 631 632 for (i = 0; i < fwspec->num_ids; ++i) 633 ipmmu_utlb_enable(domain, fwspec->ids[i]); 634 635 return 0; 636 } 637 638 static int ipmmu_iommu_identity_attach(struct iommu_domain *identity_domain, 639 struct device *dev) 640 { 641 struct iommu_domain *io_domain = iommu_get_domain_for_dev(dev); 642 struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); 643 struct ipmmu_vmsa_domain *domain; 644 unsigned int i; 645 646 if (io_domain == identity_domain || !io_domain) 647 return 0; 648 649 domain = to_vmsa_domain(io_domain); 650 for (i = 0; i < fwspec->num_ids; ++i) 651 ipmmu_utlb_disable(domain, fwspec->ids[i]); 652 653 /* 654 * TODO: Optimize by disabling the context when no device is attached. 655 */ 656 return 0; 657 } 658 659 static struct iommu_domain_ops ipmmu_iommu_identity_ops = { 660 .attach_dev = ipmmu_iommu_identity_attach, 661 }; 662 663 static struct iommu_domain ipmmu_iommu_identity_domain = { 664 .type = IOMMU_DOMAIN_IDENTITY, 665 .ops = &ipmmu_iommu_identity_ops, 666 }; 667 668 static int ipmmu_map(struct iommu_domain *io_domain, unsigned long iova, 669 phys_addr_t paddr, size_t pgsize, size_t pgcount, 670 int prot, gfp_t gfp, size_t *mapped) 671 { 672 struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain); 673 674 return domain->iop->map_pages(domain->iop, iova, paddr, pgsize, pgcount, 675 prot, gfp, mapped); 676 } 677 678 static size_t ipmmu_unmap(struct iommu_domain *io_domain, unsigned long iova, 679 size_t pgsize, size_t pgcount, 680 struct iommu_iotlb_gather *gather) 681 { 682 struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain); 683 684 return domain->iop->unmap_pages(domain->iop, iova, pgsize, pgcount, gather); 685 } 686 687 static void ipmmu_flush_iotlb_all(struct iommu_domain *io_domain) 688 { 689 struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain); 690 691 if (domain->mmu) 692 ipmmu_tlb_flush_all(domain); 693 } 694 695 static void ipmmu_iotlb_sync(struct iommu_domain *io_domain, 696 struct iommu_iotlb_gather *gather) 697 { 698 ipmmu_flush_iotlb_all(io_domain); 699 } 700 701 static phys_addr_t ipmmu_iova_to_phys(struct iommu_domain *io_domain, 702 dma_addr_t iova) 703 { 704 struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain); 705 706 /* TODO: Is locking needed ? */ 707 708 return domain->iop->iova_to_phys(domain->iop, iova); 709 } 710 711 static int ipmmu_init_platform_device(struct device *dev, 712 const struct of_phandle_args *args) 713 { 714 struct platform_device *ipmmu_pdev; 715 716 ipmmu_pdev = of_find_device_by_node(args->np); 717 if (!ipmmu_pdev) 718 return -ENODEV; 719 720 dev_iommu_priv_set(dev, platform_get_drvdata(ipmmu_pdev)); 721 722 return 0; 723 } 724 725 static const struct soc_device_attribute soc_needs_opt_in[] = { 726 { .family = "R-Car Gen3", }, 727 { .family = "R-Car Gen4", }, 728 { .family = "RZ/G2", }, 729 { /* sentinel */ } 730 }; 731 732 static const struct soc_device_attribute soc_denylist[] = { 733 { .soc_id = "r8a774a1", }, 734 { .soc_id = "r8a7795", .revision = "ES2.*" }, 735 { .soc_id = "r8a7796", }, 736 { /* sentinel */ } 737 }; 738 739 static const char * const devices_allowlist[] = { 740 "ee100000.mmc", 741 "ee120000.mmc", 742 "ee140000.mmc", 743 "ee160000.mmc" 744 }; 745 746 static bool ipmmu_device_is_allowed(struct device *dev) 747 { 748 unsigned int i; 749 750 /* 751 * R-Car Gen3/4 and RZ/G2 use the allow list to opt-in devices. 752 * For Other SoCs, this returns true anyway. 753 */ 754 if (!soc_device_match(soc_needs_opt_in)) 755 return true; 756 757 /* Check whether this SoC can use the IPMMU correctly or not */ 758 if (soc_device_match(soc_denylist)) 759 return false; 760 761 /* Check whether this device is a PCI device */ 762 if (dev_is_pci(dev)) 763 return true; 764 765 /* Check whether this device can work with the IPMMU */ 766 for (i = 0; i < ARRAY_SIZE(devices_allowlist); i++) { 767 if (!strcmp(dev_name(dev), devices_allowlist[i])) 768 return true; 769 } 770 771 /* Otherwise, do not allow use of IPMMU */ 772 return false; 773 } 774 775 static int ipmmu_of_xlate(struct device *dev, 776 const struct of_phandle_args *spec) 777 { 778 if (!ipmmu_device_is_allowed(dev)) 779 return -ENODEV; 780 781 iommu_fwspec_add_ids(dev, spec->args, 1); 782 783 /* Initialize once - xlate() will call multiple times */ 784 if (to_ipmmu(dev)) 785 return 0; 786 787 return ipmmu_init_platform_device(dev, spec); 788 } 789 790 static int ipmmu_init_arm_mapping(struct device *dev) 791 { 792 struct ipmmu_vmsa_device *mmu = to_ipmmu(dev); 793 int ret; 794 795 /* 796 * Create the ARM mapping, used by the ARM DMA mapping core to allocate 797 * VAs. This will allocate a corresponding IOMMU domain. 798 * 799 * TODO: 800 * - Create one mapping per context (TLB). 801 * - Make the mapping size configurable ? We currently use a 2GB mapping 802 * at a 1GB offset to ensure that NULL VAs will fault. 803 */ 804 if (!mmu->mapping) { 805 struct dma_iommu_mapping *mapping; 806 807 mapping = arm_iommu_create_mapping(dev, SZ_1G, SZ_2G); 808 if (IS_ERR(mapping)) { 809 dev_err(mmu->dev, "failed to create ARM IOMMU mapping\n"); 810 ret = PTR_ERR(mapping); 811 goto error; 812 } 813 814 mmu->mapping = mapping; 815 } 816 817 /* Attach the ARM VA mapping to the device. */ 818 ret = arm_iommu_attach_device(dev, mmu->mapping); 819 if (ret < 0) { 820 dev_err(dev, "Failed to attach device to VA mapping\n"); 821 goto error; 822 } 823 824 return 0; 825 826 error: 827 if (mmu->mapping) 828 arm_iommu_release_mapping(mmu->mapping); 829 830 return ret; 831 } 832 833 static struct iommu_device *ipmmu_probe_device(struct device *dev) 834 { 835 struct ipmmu_vmsa_device *mmu = to_ipmmu(dev); 836 837 /* 838 * Only let through devices that have been verified in xlate() 839 */ 840 if (!mmu) 841 return ERR_PTR(-ENODEV); 842 843 return &mmu->iommu; 844 } 845 846 static void ipmmu_probe_finalize(struct device *dev) 847 { 848 int ret = 0; 849 850 if (IS_ENABLED(CONFIG_ARM) && !IS_ENABLED(CONFIG_IOMMU_DMA)) 851 ret = ipmmu_init_arm_mapping(dev); 852 853 if (ret) 854 dev_err(dev, "Can't create IOMMU mapping - DMA-OPS will not work\n"); 855 } 856 857 static void ipmmu_release_device(struct device *dev) 858 { 859 struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); 860 struct ipmmu_vmsa_device *mmu = to_ipmmu(dev); 861 unsigned int i; 862 863 for (i = 0; i < fwspec->num_ids; ++i) { 864 unsigned int utlb = fwspec->ids[i]; 865 866 ipmmu_imuctr_write(mmu, utlb, 0); 867 mmu->utlb_ctx[utlb] = IPMMU_CTX_INVALID; 868 } 869 870 arm_iommu_release_mapping(mmu->mapping); 871 } 872 873 static const struct iommu_ops ipmmu_ops = { 874 .identity_domain = &ipmmu_iommu_identity_domain, 875 .domain_alloc_paging = ipmmu_domain_alloc_paging, 876 .probe_device = ipmmu_probe_device, 877 .release_device = ipmmu_release_device, 878 .probe_finalize = ipmmu_probe_finalize, 879 /* 880 * FIXME: The device grouping is a fixed property of the hardware's 881 * ability to isolate and control DMA, it should not depend on kconfig. 882 */ 883 .device_group = IS_ENABLED(CONFIG_ARM) && !IS_ENABLED(CONFIG_IOMMU_DMA) 884 ? generic_device_group : generic_single_device_group, 885 .pgsize_bitmap = SZ_1G | SZ_2M | SZ_4K, 886 .of_xlate = ipmmu_of_xlate, 887 .default_domain_ops = &(const struct iommu_domain_ops) { 888 .attach_dev = ipmmu_attach_device, 889 .map_pages = ipmmu_map, 890 .unmap_pages = ipmmu_unmap, 891 .flush_iotlb_all = ipmmu_flush_iotlb_all, 892 .iotlb_sync = ipmmu_iotlb_sync, 893 .iova_to_phys = ipmmu_iova_to_phys, 894 .free = ipmmu_domain_free, 895 } 896 }; 897 898 /* ----------------------------------------------------------------------------- 899 * Probe/remove and init 900 */ 901 902 static void ipmmu_device_reset(struct ipmmu_vmsa_device *mmu) 903 { 904 unsigned int i; 905 906 /* Disable all contexts. */ 907 for (i = 0; i < mmu->num_ctx; ++i) 908 ipmmu_ctx_write(mmu, i, IMCTR, 0); 909 } 910 911 static const struct ipmmu_features ipmmu_features_default = { 912 .use_ns_alias_offset = true, 913 .has_cache_leaf_nodes = false, 914 .number_of_contexts = 1, /* software only tested with one context */ 915 .num_utlbs = 32, 916 .setup_imbuscr = true, 917 .twobit_imttbcr_sl0 = false, 918 .reserved_context = false, 919 .cache_snoop = true, 920 .ctx_offset_base = 0, 921 .ctx_offset_stride = 0x40, 922 .utlb_offset_base = 0, 923 }; 924 925 static const struct ipmmu_features ipmmu_features_rcar_gen3 = { 926 .use_ns_alias_offset = false, 927 .has_cache_leaf_nodes = true, 928 .number_of_contexts = 8, 929 .num_utlbs = 48, 930 .setup_imbuscr = false, 931 .twobit_imttbcr_sl0 = true, 932 .reserved_context = true, 933 .cache_snoop = false, 934 .ctx_offset_base = 0, 935 .ctx_offset_stride = 0x40, 936 .utlb_offset_base = 0, 937 }; 938 939 static const struct ipmmu_features ipmmu_features_rcar_gen4 = { 940 .use_ns_alias_offset = false, 941 .has_cache_leaf_nodes = true, 942 .number_of_contexts = 16, 943 .num_utlbs = 64, 944 .setup_imbuscr = false, 945 .twobit_imttbcr_sl0 = true, 946 .reserved_context = true, 947 .cache_snoop = false, 948 .ctx_offset_base = 0x10000, 949 .ctx_offset_stride = 0x1040, 950 .utlb_offset_base = 0x3000, 951 }; 952 953 static const struct of_device_id ipmmu_of_ids[] = { 954 { 955 .compatible = "renesas,ipmmu-vmsa", 956 .data = &ipmmu_features_default, 957 }, { 958 .compatible = "renesas,ipmmu-r8a774a1", 959 .data = &ipmmu_features_rcar_gen3, 960 }, { 961 .compatible = "renesas,ipmmu-r8a774b1", 962 .data = &ipmmu_features_rcar_gen3, 963 }, { 964 .compatible = "renesas,ipmmu-r8a774c0", 965 .data = &ipmmu_features_rcar_gen3, 966 }, { 967 .compatible = "renesas,ipmmu-r8a774e1", 968 .data = &ipmmu_features_rcar_gen3, 969 }, { 970 .compatible = "renesas,ipmmu-r8a7795", 971 .data = &ipmmu_features_rcar_gen3, 972 }, { 973 .compatible = "renesas,ipmmu-r8a7796", 974 .data = &ipmmu_features_rcar_gen3, 975 }, { 976 .compatible = "renesas,ipmmu-r8a77961", 977 .data = &ipmmu_features_rcar_gen3, 978 }, { 979 .compatible = "renesas,ipmmu-r8a77965", 980 .data = &ipmmu_features_rcar_gen3, 981 }, { 982 .compatible = "renesas,ipmmu-r8a77970", 983 .data = &ipmmu_features_rcar_gen3, 984 }, { 985 .compatible = "renesas,ipmmu-r8a77980", 986 .data = &ipmmu_features_rcar_gen3, 987 }, { 988 .compatible = "renesas,ipmmu-r8a77990", 989 .data = &ipmmu_features_rcar_gen3, 990 }, { 991 .compatible = "renesas,ipmmu-r8a77995", 992 .data = &ipmmu_features_rcar_gen3, 993 }, { 994 .compatible = "renesas,ipmmu-r8a779a0", 995 .data = &ipmmu_features_rcar_gen4, 996 }, { 997 .compatible = "renesas,rcar-gen4-ipmmu-vmsa", 998 .data = &ipmmu_features_rcar_gen4, 999 }, { 1000 /* Terminator */ 1001 }, 1002 }; 1003 1004 static int ipmmu_probe(struct platform_device *pdev) 1005 { 1006 struct ipmmu_vmsa_device *mmu; 1007 int irq; 1008 int ret; 1009 1010 mmu = devm_kzalloc(&pdev->dev, sizeof(*mmu), GFP_KERNEL); 1011 if (!mmu) { 1012 dev_err(&pdev->dev, "cannot allocate device data\n"); 1013 return -ENOMEM; 1014 } 1015 1016 mmu->dev = &pdev->dev; 1017 spin_lock_init(&mmu->lock); 1018 bitmap_zero(mmu->ctx, IPMMU_CTX_MAX); 1019 mmu->features = of_device_get_match_data(&pdev->dev); 1020 memset(mmu->utlb_ctx, IPMMU_CTX_INVALID, mmu->features->num_utlbs); 1021 ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(40)); 1022 if (ret) 1023 return ret; 1024 1025 /* Map I/O memory and request IRQ. */ 1026 mmu->base = devm_platform_ioremap_resource(pdev, 0); 1027 if (IS_ERR(mmu->base)) 1028 return PTR_ERR(mmu->base); 1029 1030 /* 1031 * The IPMMU has two register banks, for secure and non-secure modes. 1032 * The bank mapped at the beginning of the IPMMU address space 1033 * corresponds to the running mode of the CPU. When running in secure 1034 * mode the non-secure register bank is also available at an offset. 1035 * 1036 * Secure mode operation isn't clearly documented and is thus currently 1037 * not implemented in the driver. Furthermore, preliminary tests of 1038 * non-secure operation with the main register bank were not successful. 1039 * Offset the registers base unconditionally to point to the non-secure 1040 * alias space for now. 1041 */ 1042 if (mmu->features->use_ns_alias_offset) 1043 mmu->base += IM_NS_ALIAS_OFFSET; 1044 1045 mmu->num_ctx = min(IPMMU_CTX_MAX, mmu->features->number_of_contexts); 1046 1047 /* 1048 * Determine if this IPMMU instance is a root device by checking for 1049 * the lack of has_cache_leaf_nodes flag or renesas,ipmmu-main property. 1050 */ 1051 if (!mmu->features->has_cache_leaf_nodes || 1052 !of_property_present(pdev->dev.of_node, "renesas,ipmmu-main")) 1053 mmu->root = mmu; 1054 else 1055 mmu->root = ipmmu_find_root(); 1056 1057 /* 1058 * Wait until the root device has been registered for sure. 1059 */ 1060 if (!mmu->root) 1061 return -EPROBE_DEFER; 1062 1063 /* Root devices have mandatory IRQs */ 1064 if (ipmmu_is_root(mmu)) { 1065 irq = platform_get_irq(pdev, 0); 1066 if (irq < 0) 1067 return irq; 1068 1069 ret = devm_request_irq(&pdev->dev, irq, ipmmu_irq, 0, 1070 dev_name(&pdev->dev), mmu); 1071 if (ret < 0) { 1072 dev_err(&pdev->dev, "failed to request IRQ %d\n", irq); 1073 return ret; 1074 } 1075 1076 ipmmu_device_reset(mmu); 1077 1078 if (mmu->features->reserved_context) { 1079 dev_info(&pdev->dev, "IPMMU context 0 is reserved\n"); 1080 set_bit(0, mmu->ctx); 1081 } 1082 } 1083 1084 /* 1085 * Register the IPMMU to the IOMMU subsystem in the following cases: 1086 * - R-Car Gen2 IPMMU (all devices registered) 1087 * - R-Car Gen3 IPMMU (leaf devices only - skip root IPMMU-MM device) 1088 */ 1089 if (!mmu->features->has_cache_leaf_nodes || !ipmmu_is_root(mmu)) { 1090 ret = iommu_device_sysfs_add(&mmu->iommu, &pdev->dev, NULL, 1091 dev_name(&pdev->dev)); 1092 if (ret) 1093 return ret; 1094 1095 ret = iommu_device_register(&mmu->iommu, &ipmmu_ops, &pdev->dev); 1096 if (ret) 1097 return ret; 1098 } 1099 1100 /* 1101 * We can't create the ARM mapping here as it requires the bus to have 1102 * an IOMMU, which only happens when bus_set_iommu() is called in 1103 * ipmmu_init() after the probe function returns. 1104 */ 1105 1106 platform_set_drvdata(pdev, mmu); 1107 1108 return 0; 1109 } 1110 1111 static void ipmmu_remove(struct platform_device *pdev) 1112 { 1113 struct ipmmu_vmsa_device *mmu = platform_get_drvdata(pdev); 1114 1115 iommu_device_sysfs_remove(&mmu->iommu); 1116 iommu_device_unregister(&mmu->iommu); 1117 1118 arm_iommu_release_mapping(mmu->mapping); 1119 1120 ipmmu_device_reset(mmu); 1121 } 1122 1123 static int ipmmu_resume_noirq(struct device *dev) 1124 { 1125 struct ipmmu_vmsa_device *mmu = dev_get_drvdata(dev); 1126 unsigned int i; 1127 1128 /* Reset root MMU and restore contexts */ 1129 if (ipmmu_is_root(mmu)) { 1130 ipmmu_device_reset(mmu); 1131 1132 for (i = 0; i < mmu->num_ctx; i++) { 1133 if (!mmu->domains[i]) 1134 continue; 1135 1136 ipmmu_domain_setup_context(mmu->domains[i]); 1137 } 1138 } 1139 1140 /* Re-enable active micro-TLBs */ 1141 for (i = 0; i < mmu->features->num_utlbs; i++) { 1142 if (mmu->utlb_ctx[i] == IPMMU_CTX_INVALID) 1143 continue; 1144 1145 ipmmu_utlb_enable(mmu->root->domains[mmu->utlb_ctx[i]], i); 1146 } 1147 1148 return 0; 1149 } 1150 1151 static const struct dev_pm_ops ipmmu_pm = { 1152 NOIRQ_SYSTEM_SLEEP_PM_OPS(NULL, ipmmu_resume_noirq) 1153 }; 1154 1155 static struct platform_driver ipmmu_driver = { 1156 .driver = { 1157 .name = "ipmmu-vmsa", 1158 .of_match_table = ipmmu_of_ids, 1159 .pm = pm_sleep_ptr(&ipmmu_pm), 1160 }, 1161 .probe = ipmmu_probe, 1162 .remove_new = ipmmu_remove, 1163 }; 1164 builtin_platform_driver(ipmmu_driver); 1165