1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Unisoc IOMMU driver 4 * 5 * Copyright (C) 2020 Unisoc, Inc. 6 * Author: Chunyan Zhang <chunyan.zhang@unisoc.com> 7 */ 8 9 #include <linux/clk.h> 10 #include <linux/device.h> 11 #include <linux/dma-mapping.h> 12 #include <linux/errno.h> 13 #include <linux/iommu.h> 14 #include <linux/mfd/syscon.h> 15 #include <linux/module.h> 16 #include <linux/of_platform.h> 17 #include <linux/platform_device.h> 18 #include <linux/regmap.h> 19 #include <linux/slab.h> 20 21 #define SPRD_IOMMU_PAGE_SHIFT 12 22 #define SPRD_IOMMU_PAGE_SIZE SZ_4K 23 24 #define SPRD_EX_CFG 0x0 25 #define SPRD_IOMMU_VAOR_BYPASS BIT(4) 26 #define SPRD_IOMMU_GATE_EN BIT(1) 27 #define SPRD_IOMMU_EN BIT(0) 28 #define SPRD_EX_UPDATE 0x4 29 #define SPRD_EX_FIRST_VPN 0x8 30 #define SPRD_EX_VPN_RANGE 0xc 31 #define SPRD_EX_FIRST_PPN 0x10 32 #define SPRD_EX_DEFAULT_PPN 0x14 33 34 #define SPRD_IOMMU_VERSION 0x0 35 #define SPRD_VERSION_MASK GENMASK(15, 8) 36 #define SPRD_VERSION_SHIFT 0x8 37 #define SPRD_VAU_CFG 0x4 38 #define SPRD_VAU_UPDATE 0x8 39 #define SPRD_VAU_AUTH_CFG 0xc 40 #define SPRD_VAU_FIRST_PPN 0x10 41 #define SPRD_VAU_DEFAULT_PPN_RD 0x14 42 #define SPRD_VAU_DEFAULT_PPN_WR 0x18 43 #define SPRD_VAU_FIRST_VPN 0x1c 44 #define SPRD_VAU_VPN_RANGE 0x20 45 46 enum sprd_iommu_version { 47 SPRD_IOMMU_EX, 48 SPRD_IOMMU_VAU, 49 }; 50 51 /* 52 * struct sprd_iommu_device - high-level sprd IOMMU device representation, 53 * including hardware information and configuration, also driver data, etc 54 * 55 * @ver: sprd IOMMU IP version 56 * @prot_page_va: protect page base virtual address 57 * @prot_page_pa: protect page base physical address, data would be 58 * written to here while translation fault 59 * @base: mapped base address for accessing registers 60 * @dev: pointer to basic device structure 61 * @iommu: IOMMU core representation 62 * @group: IOMMU group 63 * @eb: gate clock which controls IOMMU access 64 */ 65 struct sprd_iommu_device { 66 struct sprd_iommu_domain *dom; 67 enum sprd_iommu_version ver; 68 u32 *prot_page_va; 69 dma_addr_t prot_page_pa; 70 void __iomem *base; 71 struct device *dev; 72 struct iommu_device iommu; 73 struct iommu_group *group; 74 struct clk *eb; 75 }; 76 77 struct sprd_iommu_domain { 78 spinlock_t pgtlock; /* lock for page table */ 79 struct iommu_domain domain; 80 u32 *pgt_va; /* page table virtual address base */ 81 dma_addr_t pgt_pa; /* page table physical address base */ 82 struct sprd_iommu_device *sdev; 83 }; 84 85 static const struct iommu_ops sprd_iommu_ops; 86 87 static struct sprd_iommu_domain *to_sprd_domain(struct iommu_domain *dom) 88 { 89 return container_of(dom, struct sprd_iommu_domain, domain); 90 } 91 92 static inline void 93 sprd_iommu_write(struct sprd_iommu_device *sdev, unsigned int reg, u32 val) 94 { 95 writel_relaxed(val, sdev->base + reg); 96 } 97 98 static inline u32 99 sprd_iommu_read(struct sprd_iommu_device *sdev, unsigned int reg) 100 { 101 return readl_relaxed(sdev->base + reg); 102 } 103 104 static inline void 105 sprd_iommu_update_bits(struct sprd_iommu_device *sdev, unsigned int reg, 106 u32 mask, u32 shift, u32 val) 107 { 108 u32 t = sprd_iommu_read(sdev, reg); 109 110 t = (t & (~(mask << shift))) | ((val & mask) << shift); 111 sprd_iommu_write(sdev, reg, t); 112 } 113 114 static inline int 115 sprd_iommu_get_version(struct sprd_iommu_device *sdev) 116 { 117 int ver = (sprd_iommu_read(sdev, SPRD_IOMMU_VERSION) & 118 SPRD_VERSION_MASK) >> SPRD_VERSION_SHIFT; 119 120 switch (ver) { 121 case SPRD_IOMMU_EX: 122 case SPRD_IOMMU_VAU: 123 return ver; 124 default: 125 return -EINVAL; 126 } 127 } 128 129 static size_t 130 sprd_iommu_pgt_size(struct iommu_domain *domain) 131 { 132 return ((domain->geometry.aperture_end - 133 domain->geometry.aperture_start + 1) >> 134 SPRD_IOMMU_PAGE_SHIFT) * sizeof(u32); 135 } 136 137 static struct iommu_domain *sprd_iommu_domain_alloc(unsigned int domain_type) 138 { 139 struct sprd_iommu_domain *dom; 140 141 if (domain_type != IOMMU_DOMAIN_DMA && domain_type != IOMMU_DOMAIN_UNMANAGED) 142 return NULL; 143 144 dom = kzalloc(sizeof(*dom), GFP_KERNEL); 145 if (!dom) 146 return NULL; 147 148 spin_lock_init(&dom->pgtlock); 149 150 dom->domain.geometry.aperture_start = 0; 151 dom->domain.geometry.aperture_end = SZ_256M - 1; 152 dom->domain.geometry.force_aperture = true; 153 154 return &dom->domain; 155 } 156 157 static void sprd_iommu_first_vpn(struct sprd_iommu_domain *dom) 158 { 159 struct sprd_iommu_device *sdev = dom->sdev; 160 u32 val; 161 unsigned int reg; 162 163 if (sdev->ver == SPRD_IOMMU_EX) 164 reg = SPRD_EX_FIRST_VPN; 165 else 166 reg = SPRD_VAU_FIRST_VPN; 167 168 val = dom->domain.geometry.aperture_start >> SPRD_IOMMU_PAGE_SHIFT; 169 sprd_iommu_write(sdev, reg, val); 170 } 171 172 static void sprd_iommu_vpn_range(struct sprd_iommu_domain *dom) 173 { 174 struct sprd_iommu_device *sdev = dom->sdev; 175 u32 val; 176 unsigned int reg; 177 178 if (sdev->ver == SPRD_IOMMU_EX) 179 reg = SPRD_EX_VPN_RANGE; 180 else 181 reg = SPRD_VAU_VPN_RANGE; 182 183 val = (dom->domain.geometry.aperture_end - 184 dom->domain.geometry.aperture_start) >> SPRD_IOMMU_PAGE_SHIFT; 185 sprd_iommu_write(sdev, reg, val); 186 } 187 188 static void sprd_iommu_first_ppn(struct sprd_iommu_domain *dom) 189 { 190 u32 val = dom->pgt_pa >> SPRD_IOMMU_PAGE_SHIFT; 191 struct sprd_iommu_device *sdev = dom->sdev; 192 unsigned int reg; 193 194 if (sdev->ver == SPRD_IOMMU_EX) 195 reg = SPRD_EX_FIRST_PPN; 196 else 197 reg = SPRD_VAU_FIRST_PPN; 198 199 sprd_iommu_write(sdev, reg, val); 200 } 201 202 static void sprd_iommu_default_ppn(struct sprd_iommu_device *sdev) 203 { 204 u32 val = sdev->prot_page_pa >> SPRD_IOMMU_PAGE_SHIFT; 205 206 if (sdev->ver == SPRD_IOMMU_EX) { 207 sprd_iommu_write(sdev, SPRD_EX_DEFAULT_PPN, val); 208 } else if (sdev->ver == SPRD_IOMMU_VAU) { 209 sprd_iommu_write(sdev, SPRD_VAU_DEFAULT_PPN_RD, val); 210 sprd_iommu_write(sdev, SPRD_VAU_DEFAULT_PPN_WR, val); 211 } 212 } 213 214 static void sprd_iommu_hw_en(struct sprd_iommu_device *sdev, bool en) 215 { 216 unsigned int reg_cfg; 217 u32 mask, val; 218 219 if (sdev->ver == SPRD_IOMMU_EX) 220 reg_cfg = SPRD_EX_CFG; 221 else 222 reg_cfg = SPRD_VAU_CFG; 223 224 mask = SPRD_IOMMU_EN | SPRD_IOMMU_GATE_EN; 225 val = en ? mask : 0; 226 sprd_iommu_update_bits(sdev, reg_cfg, mask, 0, val); 227 } 228 229 static void sprd_iommu_cleanup(struct sprd_iommu_domain *dom) 230 { 231 size_t pgt_size; 232 233 /* Nothing need to do if the domain hasn't been attached */ 234 if (!dom->sdev) 235 return; 236 237 pgt_size = sprd_iommu_pgt_size(&dom->domain); 238 dma_free_coherent(dom->sdev->dev, pgt_size, dom->pgt_va, dom->pgt_pa); 239 sprd_iommu_hw_en(dom->sdev, false); 240 dom->sdev = NULL; 241 } 242 243 static void sprd_iommu_domain_free(struct iommu_domain *domain) 244 { 245 struct sprd_iommu_domain *dom = to_sprd_domain(domain); 246 247 sprd_iommu_cleanup(dom); 248 kfree(dom); 249 } 250 251 static int sprd_iommu_attach_device(struct iommu_domain *domain, 252 struct device *dev) 253 { 254 struct sprd_iommu_device *sdev = dev_iommu_priv_get(dev); 255 struct sprd_iommu_domain *dom = to_sprd_domain(domain); 256 size_t pgt_size = sprd_iommu_pgt_size(domain); 257 258 /* The device is attached to this domain */ 259 if (sdev->dom == dom) 260 return 0; 261 262 /* The first time that domain is attaching to a device */ 263 if (!dom->pgt_va) { 264 dom->pgt_va = dma_alloc_coherent(sdev->dev, pgt_size, &dom->pgt_pa, GFP_KERNEL); 265 if (!dom->pgt_va) 266 return -ENOMEM; 267 268 dom->sdev = sdev; 269 } 270 271 sdev->dom = dom; 272 273 /* 274 * One sprd IOMMU serves one client device only, disabled it before 275 * configure mapping table to avoid access conflict in case other 276 * mapping table is stored in. 277 */ 278 sprd_iommu_hw_en(sdev, false); 279 sprd_iommu_first_ppn(dom); 280 sprd_iommu_first_vpn(dom); 281 sprd_iommu_vpn_range(dom); 282 sprd_iommu_default_ppn(sdev); 283 sprd_iommu_hw_en(sdev, true); 284 285 return 0; 286 } 287 288 static int sprd_iommu_map(struct iommu_domain *domain, unsigned long iova, 289 phys_addr_t paddr, size_t pgsize, size_t pgcount, 290 int prot, gfp_t gfp, size_t *mapped) 291 { 292 struct sprd_iommu_domain *dom = to_sprd_domain(domain); 293 size_t size = pgcount * SPRD_IOMMU_PAGE_SIZE; 294 unsigned long flags; 295 unsigned int i; 296 u32 *pgt_base_iova; 297 u32 pabase = (u32)paddr; 298 unsigned long start = domain->geometry.aperture_start; 299 unsigned long end = domain->geometry.aperture_end; 300 301 if (!dom->sdev) { 302 pr_err("No sprd_iommu_device attached to the domain\n"); 303 return -EINVAL; 304 } 305 306 if (iova < start || (iova + size) > (end + 1)) { 307 dev_err(dom->sdev->dev, "(iova(0x%lx) + size(%zx)) are not in the range!\n", 308 iova, size); 309 return -EINVAL; 310 } 311 312 pgt_base_iova = dom->pgt_va + ((iova - start) >> SPRD_IOMMU_PAGE_SHIFT); 313 314 spin_lock_irqsave(&dom->pgtlock, flags); 315 for (i = 0; i < pgcount; i++) { 316 pgt_base_iova[i] = pabase >> SPRD_IOMMU_PAGE_SHIFT; 317 pabase += SPRD_IOMMU_PAGE_SIZE; 318 } 319 spin_unlock_irqrestore(&dom->pgtlock, flags); 320 321 *mapped = size; 322 return 0; 323 } 324 325 static size_t sprd_iommu_unmap(struct iommu_domain *domain, unsigned long iova, 326 size_t pgsize, size_t pgcount, 327 struct iommu_iotlb_gather *iotlb_gather) 328 { 329 struct sprd_iommu_domain *dom = to_sprd_domain(domain); 330 unsigned long flags; 331 u32 *pgt_base_iova; 332 size_t size = pgcount * SPRD_IOMMU_PAGE_SIZE; 333 unsigned long start = domain->geometry.aperture_start; 334 unsigned long end = domain->geometry.aperture_end; 335 336 if (iova < start || (iova + size) > (end + 1)) 337 return 0; 338 339 pgt_base_iova = dom->pgt_va + ((iova - start) >> SPRD_IOMMU_PAGE_SHIFT); 340 341 spin_lock_irqsave(&dom->pgtlock, flags); 342 memset(pgt_base_iova, 0, pgcount * sizeof(u32)); 343 spin_unlock_irqrestore(&dom->pgtlock, flags); 344 345 return size; 346 } 347 348 static void sprd_iommu_sync_map(struct iommu_domain *domain, 349 unsigned long iova, size_t size) 350 { 351 struct sprd_iommu_domain *dom = to_sprd_domain(domain); 352 unsigned int reg; 353 354 if (dom->sdev->ver == SPRD_IOMMU_EX) 355 reg = SPRD_EX_UPDATE; 356 else 357 reg = SPRD_VAU_UPDATE; 358 359 /* clear IOMMU TLB buffer after page table updated */ 360 sprd_iommu_write(dom->sdev, reg, 0xffffffff); 361 } 362 363 static void sprd_iommu_sync(struct iommu_domain *domain, 364 struct iommu_iotlb_gather *iotlb_gather) 365 { 366 sprd_iommu_sync_map(domain, 0, 0); 367 } 368 369 static phys_addr_t sprd_iommu_iova_to_phys(struct iommu_domain *domain, 370 dma_addr_t iova) 371 { 372 struct sprd_iommu_domain *dom = to_sprd_domain(domain); 373 unsigned long flags; 374 phys_addr_t pa; 375 unsigned long start = domain->geometry.aperture_start; 376 unsigned long end = domain->geometry.aperture_end; 377 378 if (WARN_ON(iova < start || iova > end)) 379 return 0; 380 381 spin_lock_irqsave(&dom->pgtlock, flags); 382 pa = *(dom->pgt_va + ((iova - start) >> SPRD_IOMMU_PAGE_SHIFT)); 383 pa = (pa << SPRD_IOMMU_PAGE_SHIFT) + ((iova - start) & (SPRD_IOMMU_PAGE_SIZE - 1)); 384 spin_unlock_irqrestore(&dom->pgtlock, flags); 385 386 return pa; 387 } 388 389 static struct iommu_device *sprd_iommu_probe_device(struct device *dev) 390 { 391 struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); 392 struct sprd_iommu_device *sdev; 393 394 if (!fwspec || fwspec->ops != &sprd_iommu_ops) 395 return ERR_PTR(-ENODEV); 396 397 sdev = dev_iommu_priv_get(dev); 398 399 return &sdev->iommu; 400 } 401 402 static struct iommu_group *sprd_iommu_device_group(struct device *dev) 403 { 404 struct sprd_iommu_device *sdev = dev_iommu_priv_get(dev); 405 406 return iommu_group_ref_get(sdev->group); 407 } 408 409 static int sprd_iommu_of_xlate(struct device *dev, struct of_phandle_args *args) 410 { 411 struct platform_device *pdev; 412 413 if (!dev_iommu_priv_get(dev)) { 414 pdev = of_find_device_by_node(args->np); 415 dev_iommu_priv_set(dev, platform_get_drvdata(pdev)); 416 platform_device_put(pdev); 417 } 418 419 return 0; 420 } 421 422 423 static const struct iommu_ops sprd_iommu_ops = { 424 .domain_alloc = sprd_iommu_domain_alloc, 425 .probe_device = sprd_iommu_probe_device, 426 .device_group = sprd_iommu_device_group, 427 .of_xlate = sprd_iommu_of_xlate, 428 .pgsize_bitmap = SPRD_IOMMU_PAGE_SIZE, 429 .owner = THIS_MODULE, 430 .default_domain_ops = &(const struct iommu_domain_ops) { 431 .attach_dev = sprd_iommu_attach_device, 432 .map_pages = sprd_iommu_map, 433 .unmap_pages = sprd_iommu_unmap, 434 .iotlb_sync_map = sprd_iommu_sync_map, 435 .iotlb_sync = sprd_iommu_sync, 436 .iova_to_phys = sprd_iommu_iova_to_phys, 437 .free = sprd_iommu_domain_free, 438 } 439 }; 440 441 static const struct of_device_id sprd_iommu_of_match[] = { 442 { .compatible = "sprd,iommu-v1" }, 443 { }, 444 }; 445 MODULE_DEVICE_TABLE(of, sprd_iommu_of_match); 446 447 /* 448 * Clock is not required, access to some of IOMMUs is controlled by gate 449 * clk, enabled clocks for that kind of IOMMUs before accessing. 450 * Return 0 for success or no clocks found. 451 */ 452 static int sprd_iommu_clk_enable(struct sprd_iommu_device *sdev) 453 { 454 struct clk *eb; 455 456 eb = devm_clk_get_optional(sdev->dev, NULL); 457 if (!eb) 458 return 0; 459 460 if (IS_ERR(eb)) 461 return PTR_ERR(eb); 462 463 sdev->eb = eb; 464 return clk_prepare_enable(eb); 465 } 466 467 static void sprd_iommu_clk_disable(struct sprd_iommu_device *sdev) 468 { 469 if (sdev->eb) 470 clk_disable_unprepare(sdev->eb); 471 } 472 473 static int sprd_iommu_probe(struct platform_device *pdev) 474 { 475 struct sprd_iommu_device *sdev; 476 struct device *dev = &pdev->dev; 477 void __iomem *base; 478 int ret; 479 480 sdev = devm_kzalloc(dev, sizeof(*sdev), GFP_KERNEL); 481 if (!sdev) 482 return -ENOMEM; 483 484 base = devm_platform_ioremap_resource(pdev, 0); 485 if (IS_ERR(base)) { 486 dev_err(dev, "Failed to get ioremap resource.\n"); 487 return PTR_ERR(base); 488 } 489 sdev->base = base; 490 491 sdev->prot_page_va = dma_alloc_coherent(dev, SPRD_IOMMU_PAGE_SIZE, 492 &sdev->prot_page_pa, GFP_KERNEL); 493 if (!sdev->prot_page_va) 494 return -ENOMEM; 495 496 platform_set_drvdata(pdev, sdev); 497 sdev->dev = dev; 498 499 /* All the client devices are in the same iommu-group */ 500 sdev->group = iommu_group_alloc(); 501 if (IS_ERR(sdev->group)) { 502 ret = PTR_ERR(sdev->group); 503 goto free_page; 504 } 505 506 ret = iommu_device_sysfs_add(&sdev->iommu, dev, NULL, dev_name(dev)); 507 if (ret) 508 goto put_group; 509 510 ret = iommu_device_register(&sdev->iommu, &sprd_iommu_ops, dev); 511 if (ret) 512 goto remove_sysfs; 513 514 ret = sprd_iommu_clk_enable(sdev); 515 if (ret) 516 goto unregister_iommu; 517 518 ret = sprd_iommu_get_version(sdev); 519 if (ret < 0) { 520 dev_err(dev, "IOMMU version(%d) is invalid.\n", ret); 521 goto disable_clk; 522 } 523 sdev->ver = ret; 524 525 return 0; 526 527 disable_clk: 528 sprd_iommu_clk_disable(sdev); 529 unregister_iommu: 530 iommu_device_unregister(&sdev->iommu); 531 remove_sysfs: 532 iommu_device_sysfs_remove(&sdev->iommu); 533 put_group: 534 iommu_group_put(sdev->group); 535 free_page: 536 dma_free_coherent(sdev->dev, SPRD_IOMMU_PAGE_SIZE, sdev->prot_page_va, sdev->prot_page_pa); 537 return ret; 538 } 539 540 static void sprd_iommu_remove(struct platform_device *pdev) 541 { 542 struct sprd_iommu_device *sdev = platform_get_drvdata(pdev); 543 544 dma_free_coherent(sdev->dev, SPRD_IOMMU_PAGE_SIZE, sdev->prot_page_va, sdev->prot_page_pa); 545 546 iommu_group_put(sdev->group); 547 sdev->group = NULL; 548 549 platform_set_drvdata(pdev, NULL); 550 iommu_device_sysfs_remove(&sdev->iommu); 551 iommu_device_unregister(&sdev->iommu); 552 } 553 554 static struct platform_driver sprd_iommu_driver = { 555 .driver = { 556 .name = "sprd-iommu", 557 .of_match_table = sprd_iommu_of_match, 558 .suppress_bind_attrs = true, 559 }, 560 .probe = sprd_iommu_probe, 561 .remove_new = sprd_iommu_remove, 562 }; 563 module_platform_driver(sprd_iommu_driver); 564 565 MODULE_DESCRIPTION("IOMMU driver for Unisoc SoCs"); 566 MODULE_ALIAS("platform:sprd-iommu"); 567 MODULE_LICENSE("GPL"); 568