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/regmap.h> 18 #include <linux/slab.h> 19 20 #define SPRD_IOMMU_PAGE_SHIFT 12 21 #define SPRD_IOMMU_PAGE_SIZE SZ_4K 22 23 #define SPRD_EX_CFG 0x0 24 #define SPRD_IOMMU_VAOR_BYPASS BIT(4) 25 #define SPRD_IOMMU_GATE_EN BIT(1) 26 #define SPRD_IOMMU_EN BIT(0) 27 #define SPRD_EX_UPDATE 0x4 28 #define SPRD_EX_FIRST_VPN 0x8 29 #define SPRD_EX_VPN_RANGE 0xc 30 #define SPRD_EX_FIRST_PPN 0x10 31 #define SPRD_EX_DEFAULT_PPN 0x14 32 33 #define SPRD_IOMMU_VERSION 0x0 34 #define SPRD_VERSION_MASK GENMASK(15, 8) 35 #define SPRD_VERSION_SHIFT 0x8 36 #define SPRD_VAU_CFG 0x4 37 #define SPRD_VAU_UPDATE 0x8 38 #define SPRD_VAU_AUTH_CFG 0xc 39 #define SPRD_VAU_FIRST_PPN 0x10 40 #define SPRD_VAU_DEFAULT_PPN_RD 0x14 41 #define SPRD_VAU_DEFAULT_PPN_WR 0x18 42 #define SPRD_VAU_FIRST_VPN 0x1c 43 #define SPRD_VAU_VPN_RANGE 0x20 44 45 enum sprd_iommu_version { 46 SPRD_IOMMU_EX, 47 SPRD_IOMMU_VAU, 48 }; 49 50 /* 51 * struct sprd_iommu_device - high-level sprd IOMMU device representation, 52 * including hardware information and configuration, also driver data, etc 53 * 54 * @ver: sprd IOMMU IP version 55 * @prot_page_va: protect page base virtual address 56 * @prot_page_pa: protect page base physical address, data would be 57 * written to here while translation fault 58 * @base: mapped base address for accessing registers 59 * @dev: pointer to basic device structure 60 * @iommu: IOMMU core representation 61 * @group: IOMMU group 62 * @eb: gate clock which controls IOMMU access 63 */ 64 struct sprd_iommu_device { 65 enum sprd_iommu_version ver; 66 u32 *prot_page_va; 67 dma_addr_t prot_page_pa; 68 void __iomem *base; 69 struct device *dev; 70 struct iommu_device iommu; 71 struct iommu_group *group; 72 struct clk *eb; 73 }; 74 75 struct sprd_iommu_domain { 76 spinlock_t pgtlock; /* lock for page table */ 77 struct iommu_domain domain; 78 u32 *pgt_va; /* page table virtual address base */ 79 dma_addr_t pgt_pa; /* page table physical address base */ 80 struct sprd_iommu_device *sdev; 81 }; 82 83 static const struct iommu_ops sprd_iommu_ops; 84 85 static struct sprd_iommu_domain *to_sprd_domain(struct iommu_domain *dom) 86 { 87 return container_of(dom, struct sprd_iommu_domain, domain); 88 } 89 90 static inline void 91 sprd_iommu_write(struct sprd_iommu_device *sdev, unsigned int reg, u32 val) 92 { 93 writel_relaxed(val, sdev->base + reg); 94 } 95 96 static inline u32 97 sprd_iommu_read(struct sprd_iommu_device *sdev, unsigned int reg) 98 { 99 return readl_relaxed(sdev->base + reg); 100 } 101 102 static inline void 103 sprd_iommu_update_bits(struct sprd_iommu_device *sdev, unsigned int reg, 104 u32 mask, u32 shift, u32 val) 105 { 106 u32 t = sprd_iommu_read(sdev, reg); 107 108 t = (t & (~(mask << shift))) | ((val & mask) << shift); 109 sprd_iommu_write(sdev, reg, t); 110 } 111 112 static inline int 113 sprd_iommu_get_version(struct sprd_iommu_device *sdev) 114 { 115 int ver = (sprd_iommu_read(sdev, SPRD_IOMMU_VERSION) & 116 SPRD_VERSION_MASK) >> SPRD_VERSION_SHIFT; 117 118 switch (ver) { 119 case SPRD_IOMMU_EX: 120 case SPRD_IOMMU_VAU: 121 return ver; 122 default: 123 return -EINVAL; 124 } 125 } 126 127 static size_t 128 sprd_iommu_pgt_size(struct iommu_domain *domain) 129 { 130 return ((domain->geometry.aperture_end - 131 domain->geometry.aperture_start + 1) >> 132 SPRD_IOMMU_PAGE_SHIFT) * sizeof(u32); 133 } 134 135 static struct iommu_domain *sprd_iommu_domain_alloc(unsigned int domain_type) 136 { 137 struct sprd_iommu_domain *dom; 138 139 if (domain_type != IOMMU_DOMAIN_DMA && domain_type != IOMMU_DOMAIN_UNMANAGED) 140 return NULL; 141 142 dom = kzalloc(sizeof(*dom), GFP_KERNEL); 143 if (!dom) 144 return NULL; 145 146 spin_lock_init(&dom->pgtlock); 147 148 dom->domain.geometry.aperture_start = 0; 149 dom->domain.geometry.aperture_end = SZ_256M - 1; 150 151 return &dom->domain; 152 } 153 154 static void sprd_iommu_domain_free(struct iommu_domain *domain) 155 { 156 struct sprd_iommu_domain *dom = to_sprd_domain(domain); 157 158 kfree(dom); 159 } 160 161 static void sprd_iommu_first_vpn(struct sprd_iommu_domain *dom) 162 { 163 struct sprd_iommu_device *sdev = dom->sdev; 164 u32 val; 165 unsigned int reg; 166 167 if (sdev->ver == SPRD_IOMMU_EX) 168 reg = SPRD_EX_FIRST_VPN; 169 else 170 reg = SPRD_VAU_FIRST_VPN; 171 172 val = dom->domain.geometry.aperture_start >> SPRD_IOMMU_PAGE_SHIFT; 173 sprd_iommu_write(sdev, reg, val); 174 } 175 176 static void sprd_iommu_vpn_range(struct sprd_iommu_domain *dom) 177 { 178 struct sprd_iommu_device *sdev = dom->sdev; 179 u32 val; 180 unsigned int reg; 181 182 if (sdev->ver == SPRD_IOMMU_EX) 183 reg = SPRD_EX_VPN_RANGE; 184 else 185 reg = SPRD_VAU_VPN_RANGE; 186 187 val = (dom->domain.geometry.aperture_end - 188 dom->domain.geometry.aperture_start) >> SPRD_IOMMU_PAGE_SHIFT; 189 sprd_iommu_write(sdev, reg, val); 190 } 191 192 static void sprd_iommu_first_ppn(struct sprd_iommu_domain *dom) 193 { 194 u32 val = dom->pgt_pa >> SPRD_IOMMU_PAGE_SHIFT; 195 struct sprd_iommu_device *sdev = dom->sdev; 196 unsigned int reg; 197 198 if (sdev->ver == SPRD_IOMMU_EX) 199 reg = SPRD_EX_FIRST_PPN; 200 else 201 reg = SPRD_VAU_FIRST_PPN; 202 203 sprd_iommu_write(sdev, reg, val); 204 } 205 206 static void sprd_iommu_default_ppn(struct sprd_iommu_device *sdev) 207 { 208 u32 val = sdev->prot_page_pa >> SPRD_IOMMU_PAGE_SHIFT; 209 210 if (sdev->ver == SPRD_IOMMU_EX) { 211 sprd_iommu_write(sdev, SPRD_EX_DEFAULT_PPN, val); 212 } else if (sdev->ver == SPRD_IOMMU_VAU) { 213 sprd_iommu_write(sdev, SPRD_VAU_DEFAULT_PPN_RD, val); 214 sprd_iommu_write(sdev, SPRD_VAU_DEFAULT_PPN_WR, val); 215 } 216 } 217 218 static void sprd_iommu_hw_en(struct sprd_iommu_device *sdev, bool en) 219 { 220 unsigned int reg_cfg; 221 u32 mask, val; 222 223 if (sdev->ver == SPRD_IOMMU_EX) 224 reg_cfg = SPRD_EX_CFG; 225 else 226 reg_cfg = SPRD_VAU_CFG; 227 228 mask = SPRD_IOMMU_EN | SPRD_IOMMU_GATE_EN; 229 val = en ? mask : 0; 230 sprd_iommu_update_bits(sdev, reg_cfg, mask, 0, val); 231 } 232 233 static int sprd_iommu_attach_device(struct iommu_domain *domain, 234 struct device *dev) 235 { 236 struct sprd_iommu_device *sdev = dev_iommu_priv_get(dev); 237 struct sprd_iommu_domain *dom = to_sprd_domain(domain); 238 size_t pgt_size = sprd_iommu_pgt_size(domain); 239 240 if (dom->sdev) { 241 pr_err("There's already a device attached to this domain.\n"); 242 return -EINVAL; 243 } 244 245 dom->pgt_va = dma_alloc_coherent(sdev->dev, pgt_size, &dom->pgt_pa, GFP_KERNEL); 246 if (!dom->pgt_va) 247 return -ENOMEM; 248 249 dom->sdev = sdev; 250 251 sprd_iommu_first_ppn(dom); 252 sprd_iommu_first_vpn(dom); 253 sprd_iommu_vpn_range(dom); 254 sprd_iommu_default_ppn(sdev); 255 sprd_iommu_hw_en(sdev, true); 256 257 return 0; 258 } 259 260 static void sprd_iommu_detach_device(struct iommu_domain *domain, 261 struct device *dev) 262 { 263 struct sprd_iommu_domain *dom = to_sprd_domain(domain); 264 struct sprd_iommu_device *sdev = dom->sdev; 265 size_t pgt_size = sprd_iommu_pgt_size(domain); 266 267 if (!sdev) 268 return; 269 270 dma_free_coherent(sdev->dev, pgt_size, dom->pgt_va, dom->pgt_pa); 271 sprd_iommu_hw_en(sdev, false); 272 dom->sdev = NULL; 273 } 274 275 static int sprd_iommu_map(struct iommu_domain *domain, unsigned long iova, 276 phys_addr_t paddr, size_t size, int prot, gfp_t gfp) 277 { 278 struct sprd_iommu_domain *dom = to_sprd_domain(domain); 279 unsigned int page_num = size >> SPRD_IOMMU_PAGE_SHIFT; 280 unsigned long flags; 281 unsigned int i; 282 u32 *pgt_base_iova; 283 u32 pabase = (u32)paddr; 284 unsigned long start = domain->geometry.aperture_start; 285 unsigned long end = domain->geometry.aperture_end; 286 287 if (!dom->sdev) { 288 pr_err("No sprd_iommu_device attached to the domain\n"); 289 return -EINVAL; 290 } 291 292 if (iova < start || (iova + size) > (end + 1)) { 293 dev_err(dom->sdev->dev, "(iova(0x%lx) + size(%zx)) are not in the range!\n", 294 iova, size); 295 return -EINVAL; 296 } 297 298 pgt_base_iova = dom->pgt_va + ((iova - start) >> SPRD_IOMMU_PAGE_SHIFT); 299 300 spin_lock_irqsave(&dom->pgtlock, flags); 301 for (i = 0; i < page_num; i++) { 302 pgt_base_iova[i] = pabase >> SPRD_IOMMU_PAGE_SHIFT; 303 pabase += SPRD_IOMMU_PAGE_SIZE; 304 } 305 spin_unlock_irqrestore(&dom->pgtlock, flags); 306 307 return 0; 308 } 309 310 static size_t sprd_iommu_unmap(struct iommu_domain *domain, unsigned long iova, 311 size_t size, struct iommu_iotlb_gather *iotlb_gather) 312 { 313 struct sprd_iommu_domain *dom = to_sprd_domain(domain); 314 unsigned long flags; 315 u32 *pgt_base_iova; 316 unsigned int page_num = size >> SPRD_IOMMU_PAGE_SHIFT; 317 unsigned long start = domain->geometry.aperture_start; 318 unsigned long end = domain->geometry.aperture_end; 319 320 if (iova < start || (iova + size) > (end + 1)) 321 return -EINVAL; 322 323 pgt_base_iova = dom->pgt_va + ((iova - start) >> SPRD_IOMMU_PAGE_SHIFT); 324 325 spin_lock_irqsave(&dom->pgtlock, flags); 326 memset(pgt_base_iova, 0, page_num * sizeof(u32)); 327 spin_unlock_irqrestore(&dom->pgtlock, flags); 328 329 return 0; 330 } 331 332 static void sprd_iommu_sync_map(struct iommu_domain *domain, 333 unsigned long iova, size_t size) 334 { 335 struct sprd_iommu_domain *dom = to_sprd_domain(domain); 336 unsigned int reg; 337 338 if (dom->sdev->ver == SPRD_IOMMU_EX) 339 reg = SPRD_EX_UPDATE; 340 else 341 reg = SPRD_VAU_UPDATE; 342 343 /* clear IOMMU TLB buffer after page table updated */ 344 sprd_iommu_write(dom->sdev, reg, 0xffffffff); 345 } 346 347 static void sprd_iommu_sync(struct iommu_domain *domain, 348 struct iommu_iotlb_gather *iotlb_gather) 349 { 350 sprd_iommu_sync_map(domain, 0, 0); 351 } 352 353 static phys_addr_t sprd_iommu_iova_to_phys(struct iommu_domain *domain, 354 dma_addr_t iova) 355 { 356 struct sprd_iommu_domain *dom = to_sprd_domain(domain); 357 unsigned long flags; 358 phys_addr_t pa; 359 unsigned long start = domain->geometry.aperture_start; 360 unsigned long end = domain->geometry.aperture_end; 361 362 if (WARN_ON(iova < start || iova > end)) 363 return 0; 364 365 spin_lock_irqsave(&dom->pgtlock, flags); 366 pa = *(dom->pgt_va + ((iova - start) >> SPRD_IOMMU_PAGE_SHIFT)); 367 pa = (pa << SPRD_IOMMU_PAGE_SHIFT) + ((iova - start) & (SPRD_IOMMU_PAGE_SIZE - 1)); 368 spin_unlock_irqrestore(&dom->pgtlock, flags); 369 370 return pa; 371 } 372 373 static struct iommu_device *sprd_iommu_probe_device(struct device *dev) 374 { 375 struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); 376 struct sprd_iommu_device *sdev; 377 378 if (!fwspec || fwspec->ops != &sprd_iommu_ops) 379 return ERR_PTR(-ENODEV); 380 381 sdev = dev_iommu_priv_get(dev); 382 383 return &sdev->iommu; 384 } 385 386 static void sprd_iommu_release_device(struct device *dev) 387 { 388 struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); 389 390 if (!fwspec || fwspec->ops != &sprd_iommu_ops) 391 return; 392 393 iommu_fwspec_free(dev); 394 } 395 396 static struct iommu_group *sprd_iommu_device_group(struct device *dev) 397 { 398 struct sprd_iommu_device *sdev = dev_iommu_priv_get(dev); 399 400 return iommu_group_ref_get(sdev->group); 401 } 402 403 static int sprd_iommu_of_xlate(struct device *dev, struct of_phandle_args *args) 404 { 405 struct platform_device *pdev; 406 407 if (!dev_iommu_priv_get(dev)) { 408 pdev = of_find_device_by_node(args->np); 409 dev_iommu_priv_set(dev, platform_get_drvdata(pdev)); 410 platform_device_put(pdev); 411 } 412 413 return 0; 414 } 415 416 417 static const struct iommu_ops sprd_iommu_ops = { 418 .domain_alloc = sprd_iommu_domain_alloc, 419 .probe_device = sprd_iommu_probe_device, 420 .release_device = sprd_iommu_release_device, 421 .device_group = sprd_iommu_device_group, 422 .of_xlate = sprd_iommu_of_xlate, 423 .pgsize_bitmap = ~0UL << SPRD_IOMMU_PAGE_SHIFT, 424 .owner = THIS_MODULE, 425 .default_domain_ops = &(const struct iommu_domain_ops) { 426 .attach_dev = sprd_iommu_attach_device, 427 .detach_dev = sprd_iommu_detach_device, 428 .map = sprd_iommu_map, 429 .unmap = sprd_iommu_unmap, 430 .iotlb_sync_map = sprd_iommu_sync_map, 431 .iotlb_sync = sprd_iommu_sync, 432 .iova_to_phys = sprd_iommu_iova_to_phys, 433 .free = sprd_iommu_domain_free, 434 } 435 }; 436 437 static const struct of_device_id sprd_iommu_of_match[] = { 438 { .compatible = "sprd,iommu-v1" }, 439 { }, 440 }; 441 MODULE_DEVICE_TABLE(of, sprd_iommu_of_match); 442 443 /* 444 * Clock is not required, access to some of IOMMUs is controlled by gate 445 * clk, enabled clocks for that kind of IOMMUs before accessing. 446 * Return 0 for success or no clocks found. 447 */ 448 static int sprd_iommu_clk_enable(struct sprd_iommu_device *sdev) 449 { 450 struct clk *eb; 451 452 eb = devm_clk_get_optional(sdev->dev, NULL); 453 if (!eb) 454 return 0; 455 456 if (IS_ERR(eb)) 457 return PTR_ERR(eb); 458 459 sdev->eb = eb; 460 return clk_prepare_enable(eb); 461 } 462 463 static void sprd_iommu_clk_disable(struct sprd_iommu_device *sdev) 464 { 465 if (sdev->eb) 466 clk_disable_unprepare(sdev->eb); 467 } 468 469 static int sprd_iommu_probe(struct platform_device *pdev) 470 { 471 struct sprd_iommu_device *sdev; 472 struct device *dev = &pdev->dev; 473 void __iomem *base; 474 int ret; 475 476 sdev = devm_kzalloc(dev, sizeof(*sdev), GFP_KERNEL); 477 if (!sdev) 478 return -ENOMEM; 479 480 base = devm_platform_ioremap_resource(pdev, 0); 481 if (IS_ERR(base)) { 482 dev_err(dev, "Failed to get ioremap resource.\n"); 483 return PTR_ERR(base); 484 } 485 sdev->base = base; 486 487 sdev->prot_page_va = dma_alloc_coherent(dev, SPRD_IOMMU_PAGE_SIZE, 488 &sdev->prot_page_pa, GFP_KERNEL); 489 if (!sdev->prot_page_va) 490 return -ENOMEM; 491 492 platform_set_drvdata(pdev, sdev); 493 sdev->dev = dev; 494 495 /* All the client devices are in the same iommu-group */ 496 sdev->group = iommu_group_alloc(); 497 if (IS_ERR(sdev->group)) { 498 ret = PTR_ERR(sdev->group); 499 goto free_page; 500 } 501 502 ret = iommu_device_sysfs_add(&sdev->iommu, dev, NULL, dev_name(dev)); 503 if (ret) 504 goto put_group; 505 506 ret = iommu_device_register(&sdev->iommu, &sprd_iommu_ops, dev); 507 if (ret) 508 goto remove_sysfs; 509 510 if (!iommu_present(&platform_bus_type)) 511 bus_set_iommu(&platform_bus_type, &sprd_iommu_ops); 512 513 ret = sprd_iommu_clk_enable(sdev); 514 if (ret) 515 goto unregister_iommu; 516 517 ret = sprd_iommu_get_version(sdev); 518 if (ret < 0) { 519 dev_err(dev, "IOMMU version(%d) is invalid.\n", ret); 520 goto disable_clk; 521 } 522 sdev->ver = ret; 523 524 return 0; 525 526 disable_clk: 527 sprd_iommu_clk_disable(sdev); 528 unregister_iommu: 529 iommu_device_unregister(&sdev->iommu); 530 remove_sysfs: 531 iommu_device_sysfs_remove(&sdev->iommu); 532 put_group: 533 iommu_group_put(sdev->group); 534 free_page: 535 dma_free_coherent(sdev->dev, SPRD_IOMMU_PAGE_SIZE, sdev->prot_page_va, sdev->prot_page_pa); 536 return ret; 537 } 538 539 static int sprd_iommu_remove(struct platform_device *pdev) 540 { 541 struct sprd_iommu_device *sdev = platform_get_drvdata(pdev); 542 543 dma_free_coherent(sdev->dev, SPRD_IOMMU_PAGE_SIZE, sdev->prot_page_va, sdev->prot_page_pa); 544 545 iommu_group_put(sdev->group); 546 sdev->group = NULL; 547 548 bus_set_iommu(&platform_bus_type, NULL); 549 550 platform_set_drvdata(pdev, NULL); 551 iommu_device_sysfs_remove(&sdev->iommu); 552 iommu_device_unregister(&sdev->iommu); 553 554 return 0; 555 } 556 557 static struct platform_driver sprd_iommu_driver = { 558 .driver = { 559 .name = "sprd-iommu", 560 .of_match_table = sprd_iommu_of_match, 561 .suppress_bind_attrs = true, 562 }, 563 .probe = sprd_iommu_probe, 564 .remove = sprd_iommu_remove, 565 }; 566 module_platform_driver(sprd_iommu_driver); 567 568 MODULE_DESCRIPTION("IOMMU driver for Unisoc SoCs"); 569 MODULE_ALIAS("platform:sprd-iommu"); 570 MODULE_LICENSE("GPL"); 571