drivers/iommu/exynos-iommu.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2011,2016 Samsung Electronics Co., Ltd.
   4  *              http://www.samsung.com
   5  */
   6
   7 #ifdef CONFIG_EXYNOS_IOMMU_DEBUG
   8 #define DEBUG
   9 #endif
  10
  11 #include <linux/clk.h>
  12 #include <linux/dma-mapping.h>
  13 #include <linux/err.h>
  14 #include <linux/io.h>
  15 #include <linux/iommu.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/kmemleak.h>
  18 #include <linux/list.h>
  19 #include <linux/of.h>
  20 #include <linux/of_platform.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/pm_runtime.h>
  23 #include <linux/slab.h>
  24
  25 typedef u32 sysmmu_iova_t;
  26 typedef u32 sysmmu_pte_t;
  27
  28 /* We do not consider super section mapping (16MB) */
  29 #define SECT_ORDER 20
  30 #define LPAGE_ORDER 16
  31 #define SPAGE_ORDER 12
  32
  33 #define SECT_SIZE (1 << SECT_ORDER)
  34 #define LPAGE_SIZE (1 << LPAGE_ORDER)
  35 #define SPAGE_SIZE (1 << SPAGE_ORDER)
  36
  37 #define SECT_MASK (~(SECT_SIZE - 1))
  38 #define LPAGE_MASK (~(LPAGE_SIZE - 1))
  39 #define SPAGE_MASK (~(SPAGE_SIZE - 1))
  40
  41 #define lv1ent_fault(sent) ((*(sent) == ZERO_LV2LINK) || \
  42                            ((*(sent) & 3) == 0) || ((*(sent) & 3) == 3))
  43 #define lv1ent_zero(sent) (*(sent) == ZERO_LV2LINK)
  44 #define lv1ent_page_zero(sent) ((*(sent) & 3) == 1)
  45 #define lv1ent_page(sent) ((*(sent) != ZERO_LV2LINK) && \
  46                           ((*(sent) & 3) == 1))
  47 #define lv1ent_section(sent) ((*(sent) & 3) == 2)
  48
  49 #define lv2ent_fault(pent) ((*(pent) & 3) == 0)
  50 #define lv2ent_small(pent) ((*(pent) & 2) == 2)
  51 #define lv2ent_large(pent) ((*(pent) & 3) == 1)
  52
  53 /*
  54  * v1.x - v3.x SYSMMU supports 32bit physical and 32bit virtual address spaces
  55  * v5.0 introduced support for 36bit physical address space by shifting
  56  * all page entry values by 4 bits.
  57  * All SYSMMU controllers in the system support the address spaces of the same
  58  * size, so PG_ENT_SHIFT can be initialized on first SYSMMU probe to proper
  59  * value (0 or 4).
  60  */
  61 static short PG_ENT_SHIFT = -1;
  62 #define SYSMMU_PG_ENT_SHIFT 0
  63 #define SYSMMU_V5_PG_ENT_SHIFT 4
  64
  65 static const sysmmu_pte_t *LV1_PROT;
  66 static const sysmmu_pte_t SYSMMU_LV1_PROT[] = {
  67         ((0 << 15) | (0 << 10)), /* no access */
  68         ((1 << 15) | (1 << 10)), /* IOMMU_READ only */
  69         ((0 << 15) | (1 << 10)), /* IOMMU_WRITE not supported, use read/write */
  70         ((0 << 15) | (1 << 10)), /* IOMMU_READ | IOMMU_WRITE */
  71 };
  72 static const sysmmu_pte_t SYSMMU_V5_LV1_PROT[] = {
  73         (0 << 4), /* no access */
  74         (1 << 4), /* IOMMU_READ only */
  75         (2 << 4), /* IOMMU_WRITE only */
  76         (3 << 4), /* IOMMU_READ | IOMMU_WRITE */
  77 };
  78
  79 static const sysmmu_pte_t *LV2_PROT;
  80 static const sysmmu_pte_t SYSMMU_LV2_PROT[] = {
  81         ((0 << 9) | (0 << 4)), /* no access */
  82         ((1 << 9) | (1 << 4)), /* IOMMU_READ only */
  83         ((0 << 9) | (1 << 4)), /* IOMMU_WRITE not supported, use read/write */
  84         ((0 << 9) | (1 << 4)), /* IOMMU_READ | IOMMU_WRITE */
  85 };
  86 static const sysmmu_pte_t SYSMMU_V5_LV2_PROT[] = {
  87         (0 << 2), /* no access */
  88         (1 << 2), /* IOMMU_READ only */
  89         (2 << 2), /* IOMMU_WRITE only */
  90         (3 << 2), /* IOMMU_READ | IOMMU_WRITE */
  91 };
  92
  93 #define SYSMMU_SUPPORTED_PROT_BITS (IOMMU_READ | IOMMU_WRITE)
  94
  95 #define sect_to_phys(ent) (((phys_addr_t) ent) << PG_ENT_SHIFT)
  96 #define section_phys(sent) (sect_to_phys(*(sent)) & SECT_MASK)
  97 #define section_offs(iova) (iova & (SECT_SIZE - 1))
  98 #define lpage_phys(pent) (sect_to_phys(*(pent)) & LPAGE_MASK)
  99 #define lpage_offs(iova) (iova & (LPAGE_SIZE - 1))
 100 #define spage_phys(pent) (sect_to_phys(*(pent)) & SPAGE_MASK)
 101 #define spage_offs(iova) (iova & (SPAGE_SIZE - 1))
 102
 103 #define NUM_LV1ENTRIES 4096
 104 #define NUM_LV2ENTRIES (SECT_SIZE / SPAGE_SIZE)
 105
 106 static u32 lv1ent_offset(sysmmu_iova_t iova)
 107 {
 108         return iova >> SECT_ORDER;
 109 }
 110
 111 static u32 lv2ent_offset(sysmmu_iova_t iova)
 112 {
 113         return (iova >> SPAGE_ORDER) & (NUM_LV2ENTRIES - 1);
 114 }
 115
 116 #define LV1TABLE_SIZE (NUM_LV1ENTRIES * sizeof(sysmmu_pte_t))
 117 #define LV2TABLE_SIZE (NUM_LV2ENTRIES * sizeof(sysmmu_pte_t))
 118
 119 #define SPAGES_PER_LPAGE (LPAGE_SIZE / SPAGE_SIZE)
 120 #define lv2table_base(sent) (sect_to_phys(*(sent) & 0xFFFFFFC0))
 121
 122 #define mk_lv1ent_sect(pa, prot) ((pa >> PG_ENT_SHIFT) | LV1_PROT[prot] | 2)
 123 #define mk_lv1ent_page(pa) ((pa >> PG_ENT_SHIFT) | 1)
 124 #define mk_lv2ent_lpage(pa, prot) ((pa >> PG_ENT_SHIFT) | LV2_PROT[prot] | 1)
 125 #define mk_lv2ent_spage(pa, prot) ((pa >> PG_ENT_SHIFT) | LV2_PROT[prot] | 2)
 126
 127 #define CTRL_ENABLE     0x5
 128 #define CTRL_BLOCK      0x7
 129 #define CTRL_DISABLE    0x0
 130
 131 #define CFG_LRU         0x1
 132 #define CFG_EAP         (1 << 2)
 133 #define CFG_QOS(n)      ((n & 0xF) << 7)
 134 #define CFG_ACGEN       (1 << 24) /* System MMU 3.3 only */
 135 #define CFG_SYSSEL      (1 << 22) /* System MMU 3.2 only */
 136 #define CFG_FLPDCACHE   (1 << 20) /* System MMU 3.2+ only */
 137
 138 /* common registers */
 139 #define REG_MMU_CTRL            0x000
 140 #define REG_MMU_CFG             0x004
 141 #define REG_MMU_STATUS          0x008
 142 #define REG_MMU_VERSION         0x034
 143
 144 #define MMU_MAJ_VER(val)        ((val) >> 7)
 145 #define MMU_MIN_VER(val)        ((val) & 0x7F)
 146 #define MMU_RAW_VER(reg)        (((reg) >> 21) & ((1 << 11) - 1)) /* 11 bits */
 147
 148 #define MAKE_MMU_VER(maj, min)  ((((maj) & 0xF) << 7) | ((min) & 0x7F))
 149
 150 /* v1.x - v3.x registers */
 151 #define REG_MMU_FLUSH           0x00C
 152 #define REG_MMU_FLUSH_ENTRY     0x010
 153 #define REG_PT_BASE_ADDR        0x014
 154 #define REG_INT_STATUS          0x018
 155 #define REG_INT_CLEAR           0x01C
 156
 157 #define REG_PAGE_FAULT_ADDR     0x024
 158 #define REG_AW_FAULT_ADDR       0x028
 159 #define REG_AR_FAULT_ADDR       0x02C
 160 #define REG_DEFAULT_SLAVE_ADDR  0x030
 161
 162 /* v5.x registers */
 163 #define REG_V5_PT_BASE_PFN      0x00C
 164 #define REG_V5_MMU_FLUSH_ALL    0x010
 165 #define REG_V5_MMU_FLUSH_ENTRY  0x014
 166 #define REG_V5_MMU_FLUSH_RANGE  0x018
 167 #define REG_V5_MMU_FLUSH_START  0x020
 168 #define REG_V5_MMU_FLUSH_END    0x024
 169 #define REG_V5_INT_STATUS       0x060
 170 #define REG_V5_INT_CLEAR        0x064
 171 #define REG_V5_FAULT_AR_VA      0x070
 172 #define REG_V5_FAULT_AW_VA      0x080
 173
 174 #define has_sysmmu(dev)         (dev_iommu_priv_get(dev) != NULL)
 175
 176 static struct device *dma_dev;
 177 static struct kmem_cache *lv2table_kmem_cache;
 178 static sysmmu_pte_t *zero_lv2_table;
 179 #define ZERO_LV2LINK mk_lv1ent_page(virt_to_phys(zero_lv2_table))
 180
 181 static sysmmu_pte_t *section_entry(sysmmu_pte_t *pgtable, sysmmu_iova_t iova)
 182 {
 183         return pgtable + lv1ent_offset(iova);
 184 }
 185
 186 static sysmmu_pte_t *page_entry(sysmmu_pte_t *sent, sysmmu_iova_t iova)
 187 {
 188         return (sysmmu_pte_t *)phys_to_virt(
 189                                 lv2table_base(sent)) + lv2ent_offset(iova);
 190 }
 191
 192 /*
 193  * IOMMU fault information register
 194  */
 195 struct sysmmu_fault_info {
 196         unsigned int bit;       /* bit number in STATUS register */
 197         unsigned short addr_reg; /* register to read VA fault address */
 198         const char *name;       /* human readable fault name */
 199         unsigned int type;      /* fault type for report_iommu_fault */
 200 };
 201
 202 static const struct sysmmu_fault_info sysmmu_faults[] = {
 203         { 0, REG_PAGE_FAULT_ADDR, "PAGE", IOMMU_FAULT_READ },
 204         { 1, REG_AR_FAULT_ADDR, "AR MULTI-HIT", IOMMU_FAULT_READ },
 205         { 2, REG_AW_FAULT_ADDR, "AW MULTI-HIT", IOMMU_FAULT_WRITE },
 206         { 3, REG_DEFAULT_SLAVE_ADDR, "BUS ERROR", IOMMU_FAULT_READ },
 207         { 4, REG_AR_FAULT_ADDR, "AR SECURITY PROTECTION", IOMMU_FAULT_READ },
 208         { 5, REG_AR_FAULT_ADDR, "AR ACCESS PROTECTION", IOMMU_FAULT_READ },
 209         { 6, REG_AW_FAULT_ADDR, "AW SECURITY PROTECTION", IOMMU_FAULT_WRITE },
 210         { 7, REG_AW_FAULT_ADDR, "AW ACCESS PROTECTION", IOMMU_FAULT_WRITE },
 211 };
 212
 213 static const struct sysmmu_fault_info sysmmu_v5_faults[] = {
 214         { 0, REG_V5_FAULT_AR_VA, "AR PTW", IOMMU_FAULT_READ },
 215         { 1, REG_V5_FAULT_AR_VA, "AR PAGE", IOMMU_FAULT_READ },
 216         { 2, REG_V5_FAULT_AR_VA, "AR MULTI-HIT", IOMMU_FAULT_READ },
 217         { 3, REG_V5_FAULT_AR_VA, "AR ACCESS PROTECTION", IOMMU_FAULT_READ },
 218         { 4, REG_V5_FAULT_AR_VA, "AR SECURITY PROTECTION", IOMMU_FAULT_READ },
 219         { 16, REG_V5_FAULT_AW_VA, "AW PTW", IOMMU_FAULT_WRITE },
 220         { 17, REG_V5_FAULT_AW_VA, "AW PAGE", IOMMU_FAULT_WRITE },
 221         { 18, REG_V5_FAULT_AW_VA, "AW MULTI-HIT", IOMMU_FAULT_WRITE },
 222         { 19, REG_V5_FAULT_AW_VA, "AW ACCESS PROTECTION", IOMMU_FAULT_WRITE },
 223         { 20, REG_V5_FAULT_AW_VA, "AW SECURITY PROTECTION", IOMMU_FAULT_WRITE },
 224 };
 225
 226 /*
 227  * This structure is attached to dev->iommu->priv of the master device
 228  * on device add, contains a list of SYSMMU controllers defined by device tree,
 229  * which are bound to given master device. It is usually referenced by 'owner'
 230  * pointer.
 231 */
 232 struct exynos_iommu_owner {
 233         struct list_head controllers;   /* list of sysmmu_drvdata.owner_node */
 234         struct iommu_domain *domain;    /* domain this device is attached */
 235         struct mutex rpm_lock;          /* for runtime pm of all sysmmus */
 236 };
 237
 238 /*
 239  * This structure exynos specific generalization of struct iommu_domain.
 240  * It contains list of SYSMMU controllers from all master devices, which has
 241  * been attached to this domain and page tables of IO address space defined by
 242  * it. It is usually referenced by 'domain' pointer.
 243  */
 244 struct exynos_iommu_domain {
 245         struct list_head clients; /* list of sysmmu_drvdata.domain_node */
 246         sysmmu_pte_t *pgtable;  /* lv1 page table, 16KB */
 247         short *lv2entcnt;       /* free lv2 entry counter for each section */
 248         spinlock_t lock;        /* lock for modyfying list of clients */
 249         spinlock_t pgtablelock; /* lock for modifying page table @ pgtable */
 250         struct iommu_domain domain; /* generic domain data structure */
 251 };
 252
 253 /*
 254  * This structure hold all data of a single SYSMMU controller, this includes
 255  * hw resources like registers and clocks, pointers and list nodes to connect
 256  * it to all other structures, internal state and parameters read from device
 257  * tree. It is usually referenced by 'data' pointer.
 258  */
 259 struct sysmmu_drvdata {
 260         struct device *sysmmu;          /* SYSMMU controller device */
 261         struct device *master;          /* master device (owner) */
 262         struct device_link *link;       /* runtime PM link to master */
 263         void __iomem *sfrbase;          /* our registers */
 264         struct clk *clk;                /* SYSMMU's clock */
 265         struct clk *aclk;               /* SYSMMU's aclk clock */
 266         struct clk *pclk;               /* SYSMMU's pclk clock */
 267         struct clk *clk_master;         /* master's device clock */
 268         spinlock_t lock;                /* lock for modyfying state */
 269         bool active;                    /* current status */
 270         struct exynos_iommu_domain *domain; /* domain we belong to */
 271         struct list_head domain_node;   /* node for domain clients list */
 272         struct list_head owner_node;    /* node for owner controllers list */
 273         phys_addr_t pgtable;            /* assigned page table structure */
 274         unsigned int version;           /* our version */
 275
 276         struct iommu_device iommu;      /* IOMMU core handle */
 277 };
 278
 279 static struct exynos_iommu_domain *to_exynos_domain(struct iommu_domain *dom)
 280 {
 281         return container_of(dom, struct exynos_iommu_domain, domain);
 282 }
 283
 284 static void sysmmu_unblock(struct sysmmu_drvdata *data)
 285 {
 286         writel(CTRL_ENABLE, data->sfrbase + REG_MMU_CTRL);
 287 }
 288
 289 static bool sysmmu_block(struct sysmmu_drvdata *data)
 290 {
 291         int i = 120;
 292
 293         writel(CTRL_BLOCK, data->sfrbase + REG_MMU_CTRL);
 294         while ((i > 0) && !(readl(data->sfrbase + REG_MMU_STATUS) & 1))
 295                 --i;
 296
 297         if (!(readl(data->sfrbase + REG_MMU_STATUS) & 1)) {
 298                 sysmmu_unblock(data);
 299                 return false;
 300         }
 301
 302         return true;
 303 }
 304
 305 static void __sysmmu_tlb_invalidate(struct sysmmu_drvdata *data)
 306 {
 307         if (MMU_MAJ_VER(data->version) < 5)
 308                 writel(0x1, data->sfrbase + REG_MMU_FLUSH);
 309         else
 310                 writel(0x1, data->sfrbase + REG_V5_MMU_FLUSH_ALL);
 311 }
 312
 313 static void __sysmmu_tlb_invalidate_entry(struct sysmmu_drvdata *data,
 314                                 sysmmu_iova_t iova, unsigned int num_inv)
 315 {
 316         unsigned int i;
 317
 318         if (MMU_MAJ_VER(data->version) < 5) {
 319                 for (i = 0; i < num_inv; i++) {
 320                         writel((iova & SPAGE_MASK) | 1,
 321                                      data->sfrbase + REG_MMU_FLUSH_ENTRY);
 322                         iova += SPAGE_SIZE;
 323                 }
 324         } else {
 325                 if (num_inv == 1) {
 326                         writel((iova & SPAGE_MASK) | 1,
 327                                      data->sfrbase + REG_V5_MMU_FLUSH_ENTRY);
 328                 } else {
 329                         writel((iova & SPAGE_MASK),
 330                                      data->sfrbase + REG_V5_MMU_FLUSH_START);
 331                         writel((iova & SPAGE_MASK) + (num_inv - 1) * SPAGE_SIZE,
 332                                      data->sfrbase + REG_V5_MMU_FLUSH_END);
 333                         writel(1, data->sfrbase + REG_V5_MMU_FLUSH_RANGE);
 334                 }
 335         }
 336 }
 337
 338 static void __sysmmu_set_ptbase(struct sysmmu_drvdata *data, phys_addr_t pgd)
 339 {
 340         if (MMU_MAJ_VER(data->version) < 5)
 341                 writel(pgd, data->sfrbase + REG_PT_BASE_ADDR);
 342         else
 343                 writel(pgd >> PAGE_SHIFT,
 344                              data->sfrbase + REG_V5_PT_BASE_PFN);
 345
 346         __sysmmu_tlb_invalidate(data);
 347 }
 348
 349 static void __sysmmu_enable_clocks(struct sysmmu_drvdata *data)
 350 {
 351         BUG_ON(clk_prepare_enable(data->clk_master));
 352         BUG_ON(clk_prepare_enable(data->clk));
 353         BUG_ON(clk_prepare_enable(data->pclk));
 354         BUG_ON(clk_prepare_enable(data->aclk));
 355 }
 356
 357 static void __sysmmu_disable_clocks(struct sysmmu_drvdata *data)
 358 {
 359         clk_disable_unprepare(data->aclk);
 360         clk_disable_unprepare(data->pclk);
 361         clk_disable_unprepare(data->clk);
 362         clk_disable_unprepare(data->clk_master);
 363 }
 364
 365 static void __sysmmu_get_version(struct sysmmu_drvdata *data)
 366 {
 367         u32 ver;
 368
 369         __sysmmu_enable_clocks(data);
 370
 371         ver = readl(data->sfrbase + REG_MMU_VERSION);
 372
 373         /* controllers on some SoCs don't report proper version */
 374         if (ver == 0x80000001u)
 375                 data->version = MAKE_MMU_VER(1, 0);
 376         else
 377                 data->version = MMU_RAW_VER(ver);
 378
 379         dev_dbg(data->sysmmu, "hardware version: %d.%d\n",
 380                 MMU_MAJ_VER(data->version), MMU_MIN_VER(data->version));
 381
 382         __sysmmu_disable_clocks(data);
 383 }
 384
 385 static void show_fault_information(struct sysmmu_drvdata *data,
 386                                    const struct sysmmu_fault_info *finfo,
 387                                    sysmmu_iova_t fault_addr)
 388 {
 389         sysmmu_pte_t *ent;
 390
 391         dev_err(data->sysmmu, "%s: %s FAULT occurred at %#x\n",
 392                 dev_name(data->master), finfo->name, fault_addr);
 393         dev_dbg(data->sysmmu, "Page table base: %pa\n", &data->pgtable);
 394         ent = section_entry(phys_to_virt(data->pgtable), fault_addr);
 395         dev_dbg(data->sysmmu, "\tLv1 entry: %#x\n", *ent);
 396         if (lv1ent_page(ent)) {
 397                 ent = page_entry(ent, fault_addr);
 398                 dev_dbg(data->sysmmu, "\t Lv2 entry: %#x\n", *ent);
 399         }
 400 }
 401
 402 static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
 403 {
 404         /* SYSMMU is in blocked state when interrupt occurred. */
 405         struct sysmmu_drvdata *data = dev_id;
 406         const struct sysmmu_fault_info *finfo;
 407         unsigned int i, n, itype;
 408         sysmmu_iova_t fault_addr;
 409         unsigned short reg_status, reg_clear;
 410         int ret = -ENOSYS;
 411
 412         WARN_ON(!data->active);
 413
 414         if (MMU_MAJ_VER(data->version) < 5) {
 415                 reg_status = REG_INT_STATUS;
 416                 reg_clear = REG_INT_CLEAR;
 417                 finfo = sysmmu_faults;
 418                 n = ARRAY_SIZE(sysmmu_faults);
 419         } else {
 420                 reg_status = REG_V5_INT_STATUS;
 421                 reg_clear = REG_V5_INT_CLEAR;
 422                 finfo = sysmmu_v5_faults;
 423                 n = ARRAY_SIZE(sysmmu_v5_faults);
 424         }
 425
 426         spin_lock(&data->lock);
 427
 428         clk_enable(data->clk_master);
 429
 430         itype = __ffs(readl(data->sfrbase + reg_status));
 431         for (i = 0; i < n; i++, finfo++)
 432                 if (finfo->bit == itype)
 433                         break;
 434         /* unknown/unsupported fault */
 435         BUG_ON(i == n);
 436
 437         /* print debug message */
 438         fault_addr = readl(data->sfrbase + finfo->addr_reg);
 439         show_fault_information(data, finfo, fault_addr);
 440
 441         if (data->domain)
 442                 ret = report_iommu_fault(&data->domain->domain,
 443                                         data->master, fault_addr, finfo->type);
 444         /* fault is not recovered by fault handler */
 445         BUG_ON(ret != 0);
 446
 447         writel(1 << itype, data->sfrbase + reg_clear);
 448
 449         sysmmu_unblock(data);
 450
 451         clk_disable(data->clk_master);
 452
 453         spin_unlock(&data->lock);
 454
 455         return IRQ_HANDLED;
 456 }
 457
 458 static void __sysmmu_disable(struct sysmmu_drvdata *data)
 459 {
 460         unsigned long flags;
 461
 462         clk_enable(data->clk_master);
 463
 464         spin_lock_irqsave(&data->lock, flags);
 465         writel(CTRL_DISABLE, data->sfrbase + REG_MMU_CTRL);
 466         writel(0, data->sfrbase + REG_MMU_CFG);
 467         data->active = false;
 468         spin_unlock_irqrestore(&data->lock, flags);
 469
 470         __sysmmu_disable_clocks(data);
 471 }
 472
 473 static void __sysmmu_init_config(struct sysmmu_drvdata *data)
 474 {
 475         unsigned int cfg;
 476
 477         if (data->version <= MAKE_MMU_VER(3, 1))
 478                 cfg = CFG_LRU | CFG_QOS(15);
 479         else if (data->version <= MAKE_MMU_VER(3, 2))
 480                 cfg = CFG_LRU | CFG_QOS(15) | CFG_FLPDCACHE | CFG_SYSSEL;
 481         else
 482                 cfg = CFG_QOS(15) | CFG_FLPDCACHE | CFG_ACGEN;
 483
 484         cfg |= CFG_EAP; /* enable access protection bits check */
 485
 486         writel(cfg, data->sfrbase + REG_MMU_CFG);
 487 }
 488
 489 static void __sysmmu_enable(struct sysmmu_drvdata *data)
 490 {
 491         unsigned long flags;
 492
 493         __sysmmu_enable_clocks(data);
 494
 495         spin_lock_irqsave(&data->lock, flags);
 496         writel(CTRL_BLOCK, data->sfrbase + REG_MMU_CTRL);
 497         __sysmmu_init_config(data);
 498         __sysmmu_set_ptbase(data, data->pgtable);
 499         writel(CTRL_ENABLE, data->sfrbase + REG_MMU_CTRL);
 500         data->active = true;
 501         spin_unlock_irqrestore(&data->lock, flags);
 502
 503         /*
 504          * SYSMMU driver keeps master's clock enabled only for the short
 505          * time, while accessing the registers. For performing address
 506          * translation during DMA transaction it relies on the client
 507          * driver to enable it.
 508          */
 509         clk_disable(data->clk_master);
 510 }
 511
 512 static void sysmmu_tlb_invalidate_flpdcache(struct sysmmu_drvdata *data,
 513                                             sysmmu_iova_t iova)
 514 {
 515         unsigned long flags;
 516
 517         spin_lock_irqsave(&data->lock, flags);
 518         if (data->active && data->version >= MAKE_MMU_VER(3, 3)) {
 519                 clk_enable(data->clk_master);
 520                 if (sysmmu_block(data)) {
 521                         if (data->version >= MAKE_MMU_VER(5, 0))
 522                                 __sysmmu_tlb_invalidate(data);
 523                         else
 524                                 __sysmmu_tlb_invalidate_entry(data, iova, 1);
 525                         sysmmu_unblock(data);
 526                 }
 527                 clk_disable(data->clk_master);
 528         }
 529         spin_unlock_irqrestore(&data->lock, flags);
 530 }
 531
 532 static void sysmmu_tlb_invalidate_entry(struct sysmmu_drvdata *data,
 533                                         sysmmu_iova_t iova, size_t size)
 534 {
 535         unsigned long flags;
 536
 537         spin_lock_irqsave(&data->lock, flags);
 538         if (data->active) {
 539                 unsigned int num_inv = 1;
 540
 541                 clk_enable(data->clk_master);
 542
 543                 /*
 544                  * L2TLB invalidation required
 545                  * 4KB page: 1 invalidation
 546                  * 64KB page: 16 invalidations
 547                  * 1MB page: 64 invalidations
 548                  * because it is set-associative TLB
 549                  * with 8-way and 64 sets.
 550                  * 1MB page can be cached in one of all sets.
 551                  * 64KB page can be one of 16 consecutive sets.
 552                  */
 553                 if (MMU_MAJ_VER(data->version) == 2)
 554                         num_inv = min_t(unsigned int, size / PAGE_SIZE, 64);
 555
 556                 if (sysmmu_block(data)) {
 557                         __sysmmu_tlb_invalidate_entry(data, iova, num_inv);
 558                         sysmmu_unblock(data);
 559                 }
 560                 clk_disable(data->clk_master);
 561         }
 562         spin_unlock_irqrestore(&data->lock, flags);
 563 }
 564
 565 static const struct iommu_ops exynos_iommu_ops;
 566
 567 static int exynos_sysmmu_probe(struct platform_device *pdev)
 568 {
 569         int irq, ret;
 570         struct device *dev = &pdev->dev;
 571         struct sysmmu_drvdata *data;
 572         struct resource *res;
 573
 574         data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
 575         if (!data)
 576                 return -ENOMEM;
 577
 578         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 579         data->sfrbase = devm_ioremap_resource(dev, res);
 580         if (IS_ERR(data->sfrbase))
 581                 return PTR_ERR(data->sfrbase);
 582
 583         irq = platform_get_irq(pdev, 0);
 584         if (irq <= 0)
 585                 return irq;
 586
 587         ret = devm_request_irq(dev, irq, exynos_sysmmu_irq, 0,
 588                                 dev_name(dev), data);
 589         if (ret) {
 590                 dev_err(dev, "Unabled to register handler of irq %d\n", irq);
 591                 return ret;
 592         }
 593
 594         data->clk = devm_clk_get(dev, "sysmmu");
 595         if (PTR_ERR(data->clk) == -ENOENT)
 596                 data->clk = NULL;
 597         else if (IS_ERR(data->clk))
 598                 return PTR_ERR(data->clk);
 599
 600         data->aclk = devm_clk_get(dev, "aclk");
 601         if (PTR_ERR(data->aclk) == -ENOENT)
 602                 data->aclk = NULL;
 603         else if (IS_ERR(data->aclk))
 604                 return PTR_ERR(data->aclk);
 605
 606         data->pclk = devm_clk_get(dev, "pclk");
 607         if (PTR_ERR(data->pclk) == -ENOENT)
 608                 data->pclk = NULL;
 609         else if (IS_ERR(data->pclk))
 610                 return PTR_ERR(data->pclk);
 611
 612         if (!data->clk && (!data->aclk || !data->pclk)) {
 613                 dev_err(dev, "Failed to get device clock(s)!\n");
 614                 return -ENOSYS;
 615         }
 616
 617         data->clk_master = devm_clk_get(dev, "master");
 618         if (PTR_ERR(data->clk_master) == -ENOENT)
 619                 data->clk_master = NULL;
 620         else if (IS_ERR(data->clk_master))
 621                 return PTR_ERR(data->clk_master);
 622
 623         data->sysmmu = dev;
 624         spin_lock_init(&data->lock);
 625
 626         ret = iommu_device_sysfs_add(&data->iommu, &pdev->dev, NULL,
 627                                      dev_name(data->sysmmu));
 628         if (ret)
 629                 return ret;
 630
 631         ret = iommu_device_register(&data->iommu, &exynos_iommu_ops, dev);
 632         if (ret)
 633                 return ret;
 634
 635         platform_set_drvdata(pdev, data);
 636
 637         __sysmmu_get_version(data);
 638         if (PG_ENT_SHIFT < 0) {
 639                 if (MMU_MAJ_VER(data->version) < 5) {
 640                         PG_ENT_SHIFT = SYSMMU_PG_ENT_SHIFT;
 641                         LV1_PROT = SYSMMU_LV1_PROT;
 642                         LV2_PROT = SYSMMU_LV2_PROT;
 643                 } else {
 644                         PG_ENT_SHIFT = SYSMMU_V5_PG_ENT_SHIFT;
 645                         LV1_PROT = SYSMMU_V5_LV1_PROT;
 646                         LV2_PROT = SYSMMU_V5_LV2_PROT;
 647                 }
 648         }
 649
 650         /*
 651          * use the first registered sysmmu device for performing
 652          * dma mapping operations on iommu page tables (cpu cache flush)
 653          */
 654         if (!dma_dev)
 655                 dma_dev = &pdev->dev;
 656
 657         pm_runtime_enable(dev);
 658
 659         return 0;
 660 }
 661
 662 static int __maybe_unused exynos_sysmmu_suspend(struct device *dev)
 663 {
 664         struct sysmmu_drvdata *data = dev_get_drvdata(dev);
 665         struct device *master = data->master;
 666
 667         if (master) {
 668                 struct exynos_iommu_owner *owner = dev_iommu_priv_get(master);
 669
 670                 mutex_lock(&owner->rpm_lock);
 671                 if (data->domain) {
 672                         dev_dbg(data->sysmmu, "saving state\n");
 673                         __sysmmu_disable(data);
 674                 }
 675                 mutex_unlock(&owner->rpm_lock);
 676         }
 677         return 0;
 678 }
 679
 680 static int __maybe_unused exynos_sysmmu_resume(struct device *dev)
 681 {
 682         struct sysmmu_drvdata *data = dev_get_drvdata(dev);
 683         struct device *master = data->master;
 684
 685         if (master) {
 686                 struct exynos_iommu_owner *owner = dev_iommu_priv_get(master);
 687
 688                 mutex_lock(&owner->rpm_lock);
 689                 if (data->domain) {
 690                         dev_dbg(data->sysmmu, "restoring state\n");
 691                         __sysmmu_enable(data);
 692                 }
 693                 mutex_unlock(&owner->rpm_lock);
 694         }
 695         return 0;
 696 }
 697
 698 static const struct dev_pm_ops sysmmu_pm_ops = {
 699         SET_RUNTIME_PM_OPS(exynos_sysmmu_suspend, exynos_sysmmu_resume, NULL)
 700         SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
 701                                 pm_runtime_force_resume)
 702 };
 703
 704 static const struct of_device_id sysmmu_of_match[] = {
 705         { .compatible   = "samsung,exynos-sysmmu", },
 706         { },
 707 };
 708
 709 static struct platform_driver exynos_sysmmu_driver __refdata = {
 710         .probe  = exynos_sysmmu_probe,
 711         .driver = {
 712                 .name           = "exynos-sysmmu",
 713                 .of_match_table = sysmmu_of_match,
 714                 .pm             = &sysmmu_pm_ops,
 715                 .suppress_bind_attrs = true,
 716         }
 717 };
 718
 719 static inline void exynos_iommu_set_pte(sysmmu_pte_t *ent, sysmmu_pte_t val)
 720 {
 721         dma_sync_single_for_cpu(dma_dev, virt_to_phys(ent), sizeof(*ent),
 722                                 DMA_TO_DEVICE);
 723         *ent = cpu_to_le32(val);
 724         dma_sync_single_for_device(dma_dev, virt_to_phys(ent), sizeof(*ent),
 725                                    DMA_TO_DEVICE);
 726 }
 727
 728 static struct iommu_domain *exynos_iommu_domain_alloc(unsigned type)
 729 {
 730         struct exynos_iommu_domain *domain;
 731         dma_addr_t handle;
 732         int i;
 733
 734         /* Check if correct PTE offsets are initialized */
 735         BUG_ON(PG_ENT_SHIFT < 0 || !dma_dev);
 736
 737         if (type != IOMMU_DOMAIN_DMA && type != IOMMU_DOMAIN_UNMANAGED)
 738                 return NULL;
 739
 740         domain = kzalloc(sizeof(*domain), GFP_KERNEL);
 741         if (!domain)
 742                 return NULL;
 743
 744         domain->pgtable = (sysmmu_pte_t *)__get_free_pages(GFP_KERNEL, 2);
 745         if (!domain->pgtable)
 746                 goto err_pgtable;
 747
 748         domain->lv2entcnt = (short *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, 1);
 749         if (!domain->lv2entcnt)
 750                 goto err_counter;
 751
 752         /* Workaround for System MMU v3.3 to prevent caching 1MiB mapping */
 753         for (i = 0; i < NUM_LV1ENTRIES; i++)
 754                 domain->pgtable[i] = ZERO_LV2LINK;
 755
 756         handle = dma_map_single(dma_dev, domain->pgtable, LV1TABLE_SIZE,
 757                                 DMA_TO_DEVICE);
 758         /* For mapping page table entries we rely on dma == phys */
 759         BUG_ON(handle != virt_to_phys(domain->pgtable));
 760         if (dma_mapping_error(dma_dev, handle))
 761                 goto err_lv2ent;
 762
 763         spin_lock_init(&domain->lock);
 764         spin_lock_init(&domain->pgtablelock);
 765         INIT_LIST_HEAD(&domain->clients);
 766
 767         domain->domain.geometry.aperture_start = 0;
 768         domain->domain.geometry.aperture_end   = ~0UL;
 769         domain->domain.geometry.force_aperture = true;
 770
 771         return &domain->domain;
 772
 773 err_lv2ent:
 774         free_pages((unsigned long)domain->lv2entcnt, 1);
 775 err_counter:
 776         free_pages((unsigned long)domain->pgtable, 2);
 777 err_pgtable:
 778         kfree(domain);
 779         return NULL;
 780 }
 781
 782 static void exynos_iommu_domain_free(struct iommu_domain *iommu_domain)
 783 {
 784         struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
 785         struct sysmmu_drvdata *data, *next;
 786         unsigned long flags;
 787         int i;
 788
 789         WARN_ON(!list_empty(&domain->clients));
 790
 791         spin_lock_irqsave(&domain->lock, flags);
 792
 793         list_for_each_entry_safe(data, next, &domain->clients, domain_node) {
 794                 spin_lock(&data->lock);
 795                 __sysmmu_disable(data);
 796                 data->pgtable = 0;
 797                 data->domain = NULL;
 798                 list_del_init(&data->domain_node);
 799                 spin_unlock(&data->lock);
 800         }
 801
 802         spin_unlock_irqrestore(&domain->lock, flags);
 803
 804         dma_unmap_single(dma_dev, virt_to_phys(domain->pgtable), LV1TABLE_SIZE,
 805                          DMA_TO_DEVICE);
 806
 807         for (i = 0; i < NUM_LV1ENTRIES; i++)
 808                 if (lv1ent_page(domain->pgtable + i)) {
 809                         phys_addr_t base = lv2table_base(domain->pgtable + i);
 810
 811                         dma_unmap_single(dma_dev, base, LV2TABLE_SIZE,
 812                                          DMA_TO_DEVICE);
 813                         kmem_cache_free(lv2table_kmem_cache,
 814                                         phys_to_virt(base));
 815                 }
 816
 817         free_pages((unsigned long)domain->pgtable, 2);
 818         free_pages((unsigned long)domain->lv2entcnt, 1);
 819         kfree(domain);
 820 }
 821
 822 static void exynos_iommu_detach_device(struct iommu_domain *iommu_domain,
 823                                     struct device *dev)
 824 {
 825         struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
 826         struct exynos_iommu_owner *owner = dev_iommu_priv_get(dev);
 827         phys_addr_t pagetable = virt_to_phys(domain->pgtable);
 828         struct sysmmu_drvdata *data, *next;
 829         unsigned long flags;
 830
 831         if (!has_sysmmu(dev) || owner->domain != iommu_domain)
 832                 return;
 833
 834         mutex_lock(&owner->rpm_lock);
 835
 836         list_for_each_entry(data, &owner->controllers, owner_node) {
 837                 pm_runtime_get_noresume(data->sysmmu);
 838                 if (pm_runtime_active(data->sysmmu))
 839                         __sysmmu_disable(data);
 840                 pm_runtime_put(data->sysmmu);
 841         }
 842
 843         spin_lock_irqsave(&domain->lock, flags);
 844         list_for_each_entry_safe(data, next, &domain->clients, domain_node) {
 845                 spin_lock(&data->lock);
 846                 data->pgtable = 0;
 847                 data->domain = NULL;
 848                 list_del_init(&data->domain_node);
 849                 spin_unlock(&data->lock);
 850         }
 851         owner->domain = NULL;
 852         spin_unlock_irqrestore(&domain->lock, flags);
 853
 854         mutex_unlock(&owner->rpm_lock);
 855
 856         dev_dbg(dev, "%s: Detached IOMMU with pgtable %pa\n", __func__,
 857                 &pagetable);
 858 }
 859
 860 static int exynos_iommu_attach_device(struct iommu_domain *iommu_domain,
 861                                    struct device *dev)
 862 {
 863         struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
 864         struct exynos_iommu_owner *owner = dev_iommu_priv_get(dev);
 865         struct sysmmu_drvdata *data;
 866         phys_addr_t pagetable = virt_to_phys(domain->pgtable);
 867         unsigned long flags;
 868
 869         if (!has_sysmmu(dev))
 870                 return -ENODEV;
 871
 872         if (owner->domain)
 873                 exynos_iommu_detach_device(owner->domain, dev);
 874
 875         mutex_lock(&owner->rpm_lock);
 876
 877         spin_lock_irqsave(&domain->lock, flags);
 878         list_for_each_entry(data, &owner->controllers, owner_node) {
 879                 spin_lock(&data->lock);
 880                 data->pgtable = pagetable;
 881                 data->domain = domain;
 882                 list_add_tail(&data->domain_node, &domain->clients);
 883                 spin_unlock(&data->lock);
 884         }
 885         owner->domain = iommu_domain;
 886         spin_unlock_irqrestore(&domain->lock, flags);
 887
 888         list_for_each_entry(data, &owner->controllers, owner_node) {
 889                 pm_runtime_get_noresume(data->sysmmu);
 890                 if (pm_runtime_active(data->sysmmu))
 891                         __sysmmu_enable(data);
 892                 pm_runtime_put(data->sysmmu);
 893         }
 894
 895         mutex_unlock(&owner->rpm_lock);
 896
 897         dev_dbg(dev, "%s: Attached IOMMU with pgtable %pa\n", __func__,
 898                 &pagetable);
 899
 900         return 0;
 901 }
 902
 903 static sysmmu_pte_t *alloc_lv2entry(struct exynos_iommu_domain *domain,
 904                 sysmmu_pte_t *sent, sysmmu_iova_t iova, short *pgcounter)
 905 {
 906         if (lv1ent_section(sent)) {
 907                 WARN(1, "Trying mapping on %#08x mapped with 1MiB page", iova);
 908                 return ERR_PTR(-EADDRINUSE);
 909         }
 910
 911         if (lv1ent_fault(sent)) {
 912                 dma_addr_t handle;
 913                 sysmmu_pte_t *pent;
 914                 bool need_flush_flpd_cache = lv1ent_zero(sent);
 915
 916                 pent = kmem_cache_zalloc(lv2table_kmem_cache, GFP_ATOMIC);
 917                 BUG_ON((uintptr_t)pent & (LV2TABLE_SIZE - 1));
 918                 if (!pent)
 919                         return ERR_PTR(-ENOMEM);
 920
 921                 exynos_iommu_set_pte(sent, mk_lv1ent_page(virt_to_phys(pent)));
 922                 kmemleak_ignore(pent);
 923                 *pgcounter = NUM_LV2ENTRIES;
 924                 handle = dma_map_single(dma_dev, pent, LV2TABLE_SIZE,
 925                                         DMA_TO_DEVICE);
 926                 if (dma_mapping_error(dma_dev, handle)) {
 927                         kmem_cache_free(lv2table_kmem_cache, pent);
 928                         return ERR_PTR(-EADDRINUSE);
 929                 }
 930
 931                 /*
 932                  * If pre-fetched SLPD is a faulty SLPD in zero_l2_table,
 933                  * FLPD cache may cache the address of zero_l2_table. This
 934                  * function replaces the zero_l2_table with new L2 page table
 935                  * to write valid mappings.
 936                  * Accessing the valid area may cause page fault since FLPD
 937                  * cache may still cache zero_l2_table for the valid area
 938                  * instead of new L2 page table that has the mapping
 939                  * information of the valid area.
 940                  * Thus any replacement of zero_l2_table with other valid L2
 941                  * page table must involve FLPD cache invalidation for System
 942                  * MMU v3.3.
 943                  * FLPD cache invalidation is performed with TLB invalidation
 944                  * by VPN without blocking. It is safe to invalidate TLB without
 945                  * blocking because the target address of TLB invalidation is
 946                  * not currently mapped.
 947                  */
 948                 if (need_flush_flpd_cache) {
 949                         struct sysmmu_drvdata *data;
 950
 951                         spin_lock(&domain->lock);
 952                         list_for_each_entry(data, &domain->clients, domain_node)
 953                                 sysmmu_tlb_invalidate_flpdcache(data, iova);
 954                         spin_unlock(&domain->lock);
 955                 }
 956         }
 957
 958         return page_entry(sent, iova);
 959 }
 960
 961 static int lv1set_section(struct exynos_iommu_domain *domain,
 962                           sysmmu_pte_t *sent, sysmmu_iova_t iova,
 963                           phys_addr_t paddr, int prot, short *pgcnt)
 964 {
 965         if (lv1ent_section(sent)) {
 966                 WARN(1, "Trying mapping on 1MiB@%#08x that is mapped",
 967                         iova);
 968                 return -EADDRINUSE;
 969         }
 970
 971         if (lv1ent_page(sent)) {
 972                 if (*pgcnt != NUM_LV2ENTRIES) {
 973                         WARN(1, "Trying mapping on 1MiB@%#08x that is mapped",
 974                                 iova);
 975                         return -EADDRINUSE;
 976                 }
 977
 978                 kmem_cache_free(lv2table_kmem_cache, page_entry(sent, 0));
 979                 *pgcnt = 0;
 980         }
 981
 982         exynos_iommu_set_pte(sent, mk_lv1ent_sect(paddr, prot));
 983
 984         spin_lock(&domain->lock);
 985         if (lv1ent_page_zero(sent)) {
 986                 struct sysmmu_drvdata *data;
 987                 /*
 988                  * Flushing FLPD cache in System MMU v3.3 that may cache a FLPD
 989                  * entry by speculative prefetch of SLPD which has no mapping.
 990                  */
 991                 list_for_each_entry(data, &domain->clients, domain_node)
 992                         sysmmu_tlb_invalidate_flpdcache(data, iova);
 993         }
 994         spin_unlock(&domain->lock);
 995
 996         return 0;
 997 }
 998
 999 static int lv2set_page(sysmmu_pte_t *pent, phys_addr_t paddr, size_t size,
1000                        int prot, short *pgcnt)
1001 {
1002         if (size == SPAGE_SIZE) {
1003                 if (WARN_ON(!lv2ent_fault(pent)))
1004                         return -EADDRINUSE;
1005
1006                 exynos_iommu_set_pte(pent, mk_lv2ent_spage(paddr, prot));
1007                 *pgcnt -= 1;
1008         } else { /* size == LPAGE_SIZE */
1009                 int i;
1010                 dma_addr_t pent_base = virt_to_phys(pent);
1011
1012                 dma_sync_single_for_cpu(dma_dev, pent_base,
1013                                         sizeof(*pent) * SPAGES_PER_LPAGE,
1014                                         DMA_TO_DEVICE);
1015                 for (i = 0; i < SPAGES_PER_LPAGE; i++, pent++) {
1016                         if (WARN_ON(!lv2ent_fault(pent))) {
1017                                 if (i > 0)
1018                                         memset(pent - i, 0, sizeof(*pent) * i);
1019                                 return -EADDRINUSE;
1020                         }
1021
1022                         *pent = mk_lv2ent_lpage(paddr, prot);
1023                 }
1024                 dma_sync_single_for_device(dma_dev, pent_base,
1025                                            sizeof(*pent) * SPAGES_PER_LPAGE,
1026                                            DMA_TO_DEVICE);
1027                 *pgcnt -= SPAGES_PER_LPAGE;
1028         }
1029
1030         return 0;
1031 }
1032
1033 /*
1034  * *CAUTION* to the I/O virtual memory managers that support exynos-iommu:
1035  *
1036  * System MMU v3.x has advanced logic to improve address translation
1037  * performance with caching more page table entries by a page table walk.
1038  * However, the logic has a bug that while caching faulty page table entries,
1039  * System MMU reports page fault if the cached fault entry is hit even though
1040  * the fault entry is updated to a valid entry after the entry is cached.
1041  * To prevent caching faulty page table entries which may be updated to valid
1042  * entries later, the virtual memory manager should care about the workaround
1043  * for the problem. The following describes the workaround.
1044  *
1045  * Any two consecutive I/O virtual address regions must have a hole of 128KiB
1046  * at maximum to prevent misbehavior of System MMU 3.x (workaround for h/w bug).
1047  *
1048  * Precisely, any start address of I/O virtual region must be aligned with
1049  * the following sizes for System MMU v3.1 and v3.2.
1050  * System MMU v3.1: 128KiB
1051  * System MMU v3.2: 256KiB
1052  *
1053  * Because System MMU v3.3 caches page table entries more aggressively, it needs
1054  * more workarounds.
1055  * - Any two consecutive I/O virtual regions must have a hole of size larger
1056  *   than or equal to 128KiB.
1057  * - Start address of an I/O virtual region must be aligned by 128KiB.
1058  */
1059 static int exynos_iommu_map(struct iommu_domain *iommu_domain,
1060                             unsigned long l_iova, phys_addr_t paddr, size_t size,
1061                             int prot, gfp_t gfp)
1062 {
1063         struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
1064         sysmmu_pte_t *entry;
1065         sysmmu_iova_t iova = (sysmmu_iova_t)l_iova;
1066         unsigned long flags;
1067         int ret = -ENOMEM;
1068
1069         BUG_ON(domain->pgtable == NULL);
1070         prot &= SYSMMU_SUPPORTED_PROT_BITS;
1071
1072         spin_lock_irqsave(&domain->pgtablelock, flags);
1073
1074         entry = section_entry(domain->pgtable, iova);
1075
1076         if (size == SECT_SIZE) {
1077                 ret = lv1set_section(domain, entry, iova, paddr, prot,
1078                                      &domain->lv2entcnt[lv1ent_offset(iova)]);
1079         } else {
1080                 sysmmu_pte_t *pent;
1081
1082                 pent = alloc_lv2entry(domain, entry, iova,
1083                                       &domain->lv2entcnt[lv1ent_offset(iova)]);
1084
1085                 if (IS_ERR(pent))
1086                         ret = PTR_ERR(pent);
1087                 else
1088                         ret = lv2set_page(pent, paddr, size, prot,
1089                                        &domain->lv2entcnt[lv1ent_offset(iova)]);
1090         }
1091
1092         if (ret)
1093                 pr_err("%s: Failed(%d) to map %#zx bytes @ %#x\n",
1094                         __func__, ret, size, iova);
1095
1096         spin_unlock_irqrestore(&domain->pgtablelock, flags);
1097
1098         return ret;
1099 }
1100
1101 static void exynos_iommu_tlb_invalidate_entry(struct exynos_iommu_domain *domain,
1102                                               sysmmu_iova_t iova, size_t size)
1103 {
1104         struct sysmmu_drvdata *data;
1105         unsigned long flags;
1106
1107         spin_lock_irqsave(&domain->lock, flags);
1108
1109         list_for_each_entry(data, &domain->clients, domain_node)
1110                 sysmmu_tlb_invalidate_entry(data, iova, size);
1111
1112         spin_unlock_irqrestore(&domain->lock, flags);
1113 }
1114
1115 static size_t exynos_iommu_unmap(struct iommu_domain *iommu_domain,
1116                                  unsigned long l_iova, size_t size,
1117                                  struct iommu_iotlb_gather *gather)
1118 {
1119         struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
1120         sysmmu_iova_t iova = (sysmmu_iova_t)l_iova;
1121         sysmmu_pte_t *ent;
1122         size_t err_pgsize;
1123         unsigned long flags;
1124
1125         BUG_ON(domain->pgtable == NULL);
1126
1127         spin_lock_irqsave(&domain->pgtablelock, flags);
1128
1129         ent = section_entry(domain->pgtable, iova);
1130
1131         if (lv1ent_section(ent)) {
1132                 if (WARN_ON(size < SECT_SIZE)) {
1133                         err_pgsize = SECT_SIZE;
1134                         goto err;
1135                 }
1136
1137                 /* workaround for h/w bug in System MMU v3.3 */
1138                 exynos_iommu_set_pte(ent, ZERO_LV2LINK);
1139                 size = SECT_SIZE;
1140                 goto done;
1141         }
1142
1143         if (unlikely(lv1ent_fault(ent))) {
1144                 if (size > SECT_SIZE)
1145                         size = SECT_SIZE;
1146                 goto done;
1147         }
1148
1149         /* lv1ent_page(sent) == true here */
1150
1151         ent = page_entry(ent, iova);
1152
1153         if (unlikely(lv2ent_fault(ent))) {
1154                 size = SPAGE_SIZE;
1155                 goto done;
1156         }
1157
1158         if (lv2ent_small(ent)) {
1159                 exynos_iommu_set_pte(ent, 0);
1160                 size = SPAGE_SIZE;
1161                 domain->lv2entcnt[lv1ent_offset(iova)] += 1;
1162                 goto done;
1163         }
1164
1165         /* lv1ent_large(ent) == true here */
1166         if (WARN_ON(size < LPAGE_SIZE)) {
1167                 err_pgsize = LPAGE_SIZE;
1168                 goto err;
1169         }
1170
1171         dma_sync_single_for_cpu(dma_dev, virt_to_phys(ent),
1172                                 sizeof(*ent) * SPAGES_PER_LPAGE,
1173                                 DMA_TO_DEVICE);
1174         memset(ent, 0, sizeof(*ent) * SPAGES_PER_LPAGE);
1175         dma_sync_single_for_device(dma_dev, virt_to_phys(ent),
1176                                    sizeof(*ent) * SPAGES_PER_LPAGE,
1177                                    DMA_TO_DEVICE);
1178         size = LPAGE_SIZE;
1179         domain->lv2entcnt[lv1ent_offset(iova)] += SPAGES_PER_LPAGE;
1180 done:
1181         spin_unlock_irqrestore(&domain->pgtablelock, flags);
1182
1183         exynos_iommu_tlb_invalidate_entry(domain, iova, size);
1184
1185         return size;
1186 err:
1187         spin_unlock_irqrestore(&domain->pgtablelock, flags);
1188
1189         pr_err("%s: Failed: size(%#zx) @ %#x is smaller than page size %#zx\n",
1190                 __func__, size, iova, err_pgsize);
1191
1192         return 0;
1193 }
1194
1195 static phys_addr_t exynos_iommu_iova_to_phys(struct iommu_domain *iommu_domain,
1196                                           dma_addr_t iova)
1197 {
1198         struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
1199         sysmmu_pte_t *entry;
1200         unsigned long flags;
1201         phys_addr_t phys = 0;
1202
1203         spin_lock_irqsave(&domain->pgtablelock, flags);
1204
1205         entry = section_entry(domain->pgtable, iova);
1206
1207         if (lv1ent_section(entry)) {
1208                 phys = section_phys(entry) + section_offs(iova);
1209         } else if (lv1ent_page(entry)) {
1210                 entry = page_entry(entry, iova);
1211
1212                 if (lv2ent_large(entry))
1213                         phys = lpage_phys(entry) + lpage_offs(iova);
1214                 else if (lv2ent_small(entry))
1215                         phys = spage_phys(entry) + spage_offs(iova);
1216         }
1217
1218         spin_unlock_irqrestore(&domain->pgtablelock, flags);
1219
1220         return phys;
1221 }
1222
1223 static struct iommu_device *exynos_iommu_probe_device(struct device *dev)
1224 {
1225         struct exynos_iommu_owner *owner = dev_iommu_priv_get(dev);
1226         struct sysmmu_drvdata *data;
1227
1228         if (!has_sysmmu(dev))
1229                 return ERR_PTR(-ENODEV);
1230
1231         list_for_each_entry(data, &owner->controllers, owner_node) {
1232                 /*
1233                  * SYSMMU will be runtime activated via device link
1234                  * (dependency) to its master device, so there are no
1235                  * direct calls to pm_runtime_get/put in this driver.
1236                  */
1237                 data->link = device_link_add(dev, data->sysmmu,
1238                                              DL_FLAG_STATELESS |
1239                                              DL_FLAG_PM_RUNTIME);
1240         }
1241
1242         /* There is always at least one entry, see exynos_iommu_of_xlate() */
1243         data = list_first_entry(&owner->controllers,
1244                                 struct sysmmu_drvdata, owner_node);
1245
1246         return &data->iommu;
1247 }
1248
1249 static void exynos_iommu_release_device(struct device *dev)
1250 {
1251         struct exynos_iommu_owner *owner = dev_iommu_priv_get(dev);
1252         struct sysmmu_drvdata *data;
1253
1254         if (!has_sysmmu(dev))
1255                 return;
1256
1257         if (owner->domain) {
1258                 struct iommu_group *group = iommu_group_get(dev);
1259
1260                 if (group) {
1261                         WARN_ON(owner->domain !=
1262                                 iommu_group_default_domain(group));
1263                         exynos_iommu_detach_device(owner->domain, dev);
1264                         iommu_group_put(group);
1265                 }
1266         }
1267
1268         list_for_each_entry(data, &owner->controllers, owner_node)
1269                 device_link_del(data->link);
1270 }
1271
1272 static int exynos_iommu_of_xlate(struct device *dev,
1273                                  struct of_phandle_args *spec)
1274 {
1275         struct platform_device *sysmmu = of_find_device_by_node(spec->np);
1276         struct exynos_iommu_owner *owner = dev_iommu_priv_get(dev);
1277         struct sysmmu_drvdata *data, *entry;
1278
1279         if (!sysmmu)
1280                 return -ENODEV;
1281
1282         data = platform_get_drvdata(sysmmu);
1283         if (!data) {
1284                 put_device(&sysmmu->dev);
1285                 return -ENODEV;
1286         }
1287
1288         if (!owner) {
1289                 owner = kzalloc(sizeof(*owner), GFP_KERNEL);
1290                 if (!owner) {
1291                         put_device(&sysmmu->dev);
1292                         return -ENOMEM;
1293                 }
1294
1295                 INIT_LIST_HEAD(&owner->controllers);
1296                 mutex_init(&owner->rpm_lock);
1297                 dev_iommu_priv_set(dev, owner);
1298         }
1299
1300         list_for_each_entry(entry, &owner->controllers, owner_node)
1301                 if (entry == data)
1302                         return 0;
1303
1304         list_add_tail(&data->owner_node, &owner->controllers);
1305         data->master = dev;
1306
1307         return 0;
1308 }
1309
1310 static const struct iommu_ops exynos_iommu_ops = {
1311         .domain_alloc = exynos_iommu_domain_alloc,
1312         .device_group = generic_device_group,
1313         .probe_device = exynos_iommu_probe_device,
1314         .release_device = exynos_iommu_release_device,
1315         .pgsize_bitmap = SECT_SIZE | LPAGE_SIZE | SPAGE_SIZE,
1316         .of_xlate = exynos_iommu_of_xlate,
1317         .default_domain_ops = &(const struct iommu_domain_ops) {
1318                 .attach_dev     = exynos_iommu_attach_device,
1319                 .detach_dev     = exynos_iommu_detach_device,
1320                 .map            = exynos_iommu_map,
1321                 .unmap          = exynos_iommu_unmap,
1322                 .iova_to_phys   = exynos_iommu_iova_to_phys,
1323                 .free           = exynos_iommu_domain_free,
1324         }
1325 };
1326
1327 static int __init exynos_iommu_init(void)
1328 {
1329         struct device_node *np;
1330         int ret;
1331
1332         np = of_find_matching_node(NULL, sysmmu_of_match);
1333         if (!np)
1334                 return 0;
1335
1336         of_node_put(np);
1337
1338         lv2table_kmem_cache = kmem_cache_create("exynos-iommu-lv2table",
1339                                 LV2TABLE_SIZE, LV2TABLE_SIZE, 0, NULL);
1340         if (!lv2table_kmem_cache) {
1341                 pr_err("%s: Failed to create kmem cache\n", __func__);
1342                 return -ENOMEM;
1343         }
1344
1345         ret = platform_driver_register(&exynos_sysmmu_driver);
1346         if (ret) {
1347                 pr_err("%s: Failed to register driver\n", __func__);
1348                 goto err_reg_driver;
1349         }
1350
1351         zero_lv2_table = kmem_cache_zalloc(lv2table_kmem_cache, GFP_KERNEL);
1352         if (zero_lv2_table == NULL) {
1353                 pr_err("%s: Failed to allocate zero level2 page table\n",
1354                         __func__);
1355                 ret = -ENOMEM;
1356                 goto err_zero_lv2;
1357         }
1358
1359         ret = bus_set_iommu(&platform_bus_type, &exynos_iommu_ops);
1360         if (ret) {
1361                 pr_err("%s: Failed to register exynos-iommu driver.\n",
1362                                                                 __func__);
1363                 goto err_set_iommu;
1364         }
1365
1366         return 0;
1367 err_set_iommu:
1368         kmem_cache_free(lv2table_kmem_cache, zero_lv2_table);
1369 err_zero_lv2:
1370         platform_driver_unregister(&exynos_sysmmu_driver);
1371 err_reg_driver:
1372         kmem_cache_destroy(lv2table_kmem_cache);
1373         return ret;
1374 }
1375 core_initcall(exynos_iommu_init);