drivers/iommu/exynos-iommu.c

   1 /*
   2  * Copyright (c) 2011,2016 Samsung Electronics Co., Ltd.
   3  *              http://www.samsung.com
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  */
   9
  10 #ifdef CONFIG_EXYNOS_IOMMU_DEBUG
  11 #define DEBUG
  12 #endif
  13
  14 #include <linux/clk.h>
  15 #include <linux/dma-mapping.h>
  16 #include <linux/err.h>
  17 #include <linux/io.h>
  18 #include <linux/iommu.h>
  19 #include <linux/interrupt.h>
  20 #include <linux/list.h>
  21 #include <linux/of.h>
  22 #include <linux/of_iommu.h>
  23 #include <linux/of_platform.h>
  24 #include <linux/platform_device.h>
  25 #include <linux/pm_runtime.h>
  26 #include <linux/slab.h>
  27 #include <linux/dma-iommu.h>
  28
  29 typedef u32 sysmmu_iova_t;
  30 typedef u32 sysmmu_pte_t;
  31
  32 /* We do not consider super section mapping (16MB) */
  33 #define SECT_ORDER 20
  34 #define LPAGE_ORDER 16
  35 #define SPAGE_ORDER 12
  36
  37 #define SECT_SIZE (1 << SECT_ORDER)
  38 #define LPAGE_SIZE (1 << LPAGE_ORDER)
  39 #define SPAGE_SIZE (1 << SPAGE_ORDER)
  40
  41 #define SECT_MASK (~(SECT_SIZE - 1))
  42 #define LPAGE_MASK (~(LPAGE_SIZE - 1))
  43 #define SPAGE_MASK (~(SPAGE_SIZE - 1))
  44
  45 #define lv1ent_fault(sent) ((*(sent) == ZERO_LV2LINK) || \
  46                            ((*(sent) & 3) == 0) || ((*(sent) & 3) == 3))
  47 #define lv1ent_zero(sent) (*(sent) == ZERO_LV2LINK)
  48 #define lv1ent_page_zero(sent) ((*(sent) & 3) == 1)
  49 #define lv1ent_page(sent) ((*(sent) != ZERO_LV2LINK) && \
  50                           ((*(sent) & 3) == 1))
  51 #define lv1ent_section(sent) ((*(sent) & 3) == 2)
  52
  53 #define lv2ent_fault(pent) ((*(pent) & 3) == 0)
  54 #define lv2ent_small(pent) ((*(pent) & 2) == 2)
  55 #define lv2ent_large(pent) ((*(pent) & 3) == 1)
  56
  57 #ifdef CONFIG_BIG_ENDIAN
  58 #warning "revisit driver if we can enable big-endian ptes"
  59 #endif
  60
  61 /*
  62  * v1.x - v3.x SYSMMU supports 32bit physical and 32bit virtual address spaces
  63  * v5.0 introduced support for 36bit physical address space by shifting
  64  * all page entry values by 4 bits.
  65  * All SYSMMU controllers in the system support the address spaces of the same
  66  * size, so PG_ENT_SHIFT can be initialized on first SYSMMU probe to proper
  67  * value (0 or 4).
  68  */
  69 static short PG_ENT_SHIFT = -1;
  70 #define SYSMMU_PG_ENT_SHIFT 0
  71 #define SYSMMU_V5_PG_ENT_SHIFT 4
  72
  73 static const sysmmu_pte_t *LV1_PROT;
  74 static const sysmmu_pte_t SYSMMU_LV1_PROT[] = {
  75         ((0 << 15) | (0 << 10)), /* no access */
  76         ((1 << 15) | (1 << 10)), /* IOMMU_READ only */
  77         ((0 << 15) | (1 << 10)), /* IOMMU_WRITE not supported, use read/write */
  78         ((0 << 15) | (1 << 10)), /* IOMMU_READ | IOMMU_WRITE */
  79 };
  80 static const sysmmu_pte_t SYSMMU_V5_LV1_PROT[] = {
  81         (0 << 4), /* no access */
  82         (1 << 4), /* IOMMU_READ only */
  83         (2 << 4), /* IOMMU_WRITE only */
  84         (3 << 4), /* IOMMU_READ | IOMMU_WRITE */
  85 };
  86
  87 static const sysmmu_pte_t *LV2_PROT;
  88 static const sysmmu_pte_t SYSMMU_LV2_PROT[] = {
  89         ((0 << 9) | (0 << 4)), /* no access */
  90         ((1 << 9) | (1 << 4)), /* IOMMU_READ only */
  91         ((0 << 9) | (1 << 4)), /* IOMMU_WRITE not supported, use read/write */
  92         ((0 << 9) | (1 << 4)), /* IOMMU_READ | IOMMU_WRITE */
  93 };
  94 static const sysmmu_pte_t SYSMMU_V5_LV2_PROT[] = {
  95         (0 << 2), /* no access */
  96         (1 << 2), /* IOMMU_READ only */
  97         (2 << 2), /* IOMMU_WRITE only */
  98         (3 << 2), /* IOMMU_READ | IOMMU_WRITE */
  99 };
 100
 101 #define SYSMMU_SUPPORTED_PROT_BITS (IOMMU_READ | IOMMU_WRITE)
 102
 103 #define sect_to_phys(ent) (((phys_addr_t) ent) << PG_ENT_SHIFT)
 104 #define section_phys(sent) (sect_to_phys(*(sent)) & SECT_MASK)
 105 #define section_offs(iova) (iova & (SECT_SIZE - 1))
 106 #define lpage_phys(pent) (sect_to_phys(*(pent)) & LPAGE_MASK)
 107 #define lpage_offs(iova) (iova & (LPAGE_SIZE - 1))
 108 #define spage_phys(pent) (sect_to_phys(*(pent)) & SPAGE_MASK)
 109 #define spage_offs(iova) (iova & (SPAGE_SIZE - 1))
 110
 111 #define NUM_LV1ENTRIES 4096
 112 #define NUM_LV2ENTRIES (SECT_SIZE / SPAGE_SIZE)
 113
 114 static u32 lv1ent_offset(sysmmu_iova_t iova)
 115 {
 116         return iova >> SECT_ORDER;
 117 }
 118
 119 static u32 lv2ent_offset(sysmmu_iova_t iova)
 120 {
 121         return (iova >> SPAGE_ORDER) & (NUM_LV2ENTRIES - 1);
 122 }
 123
 124 #define LV1TABLE_SIZE (NUM_LV1ENTRIES * sizeof(sysmmu_pte_t))
 125 #define LV2TABLE_SIZE (NUM_LV2ENTRIES * sizeof(sysmmu_pte_t))
 126
 127 #define SPAGES_PER_LPAGE (LPAGE_SIZE / SPAGE_SIZE)
 128 #define lv2table_base(sent) (sect_to_phys(*(sent) & 0xFFFFFFC0))
 129
 130 #define mk_lv1ent_sect(pa, prot) ((pa >> PG_ENT_SHIFT) | LV1_PROT[prot] | 2)
 131 #define mk_lv1ent_page(pa) ((pa >> PG_ENT_SHIFT) | 1)
 132 #define mk_lv2ent_lpage(pa, prot) ((pa >> PG_ENT_SHIFT) | LV2_PROT[prot] | 1)
 133 #define mk_lv2ent_spage(pa, prot) ((pa >> PG_ENT_SHIFT) | LV2_PROT[prot] | 2)
 134
 135 #define CTRL_ENABLE     0x5
 136 #define CTRL_BLOCK      0x7
 137 #define CTRL_DISABLE    0x0
 138
 139 #define CFG_LRU         0x1
 140 #define CFG_EAP         (1 << 2)
 141 #define CFG_QOS(n)      ((n & 0xF) << 7)
 142 #define CFG_ACGEN       (1 << 24) /* System MMU 3.3 only */
 143 #define CFG_SYSSEL      (1 << 22) /* System MMU 3.2 only */
 144 #define CFG_FLPDCACHE   (1 << 20) /* System MMU 3.2+ only */
 145
 146 /* common registers */
 147 #define REG_MMU_CTRL            0x000
 148 #define REG_MMU_CFG             0x004
 149 #define REG_MMU_STATUS          0x008
 150 #define REG_MMU_VERSION         0x034
 151
 152 #define MMU_MAJ_VER(val)        ((val) >> 7)
 153 #define MMU_MIN_VER(val)        ((val) & 0x7F)
 154 #define MMU_RAW_VER(reg)        (((reg) >> 21) & ((1 << 11) - 1)) /* 11 bits */
 155
 156 #define MAKE_MMU_VER(maj, min)  ((((maj) & 0xF) << 7) | ((min) & 0x7F))
 157
 158 /* v1.x - v3.x registers */
 159 #define REG_MMU_FLUSH           0x00C
 160 #define REG_MMU_FLUSH_ENTRY     0x010
 161 #define REG_PT_BASE_ADDR        0x014
 162 #define REG_INT_STATUS          0x018
 163 #define REG_INT_CLEAR           0x01C
 164
 165 #define REG_PAGE_FAULT_ADDR     0x024
 166 #define REG_AW_FAULT_ADDR       0x028
 167 #define REG_AR_FAULT_ADDR       0x02C
 168 #define REG_DEFAULT_SLAVE_ADDR  0x030
 169
 170 /* v5.x registers */
 171 #define REG_V5_PT_BASE_PFN      0x00C
 172 #define REG_V5_MMU_FLUSH_ALL    0x010
 173 #define REG_V5_MMU_FLUSH_ENTRY  0x014
 174 #define REG_V5_MMU_FLUSH_RANGE  0x018
 175 #define REG_V5_MMU_FLUSH_START  0x020
 176 #define REG_V5_MMU_FLUSH_END    0x024
 177 #define REG_V5_INT_STATUS       0x060
 178 #define REG_V5_INT_CLEAR        0x064
 179 #define REG_V5_FAULT_AR_VA      0x070
 180 #define REG_V5_FAULT_AW_VA      0x080
 181
 182 #define has_sysmmu(dev)         (dev->archdata.iommu != NULL)
 183
 184 static struct device *dma_dev;
 185 static struct kmem_cache *lv2table_kmem_cache;
 186 static sysmmu_pte_t *zero_lv2_table;
 187 #define ZERO_LV2LINK mk_lv1ent_page(virt_to_phys(zero_lv2_table))
 188
 189 static sysmmu_pte_t *section_entry(sysmmu_pte_t *pgtable, sysmmu_iova_t iova)
 190 {
 191         return pgtable + lv1ent_offset(iova);
 192 }
 193
 194 static sysmmu_pte_t *page_entry(sysmmu_pte_t *sent, sysmmu_iova_t iova)
 195 {
 196         return (sysmmu_pte_t *)phys_to_virt(
 197                                 lv2table_base(sent)) + lv2ent_offset(iova);
 198 }
 199
 200 /*
 201  * IOMMU fault information register
 202  */
 203 struct sysmmu_fault_info {
 204         unsigned int bit;       /* bit number in STATUS register */
 205         unsigned short addr_reg; /* register to read VA fault address */
 206         const char *name;       /* human readable fault name */
 207         unsigned int type;      /* fault type for report_iommu_fault */
 208 };
 209
 210 static const struct sysmmu_fault_info sysmmu_faults[] = {
 211         { 0, REG_PAGE_FAULT_ADDR, "PAGE", IOMMU_FAULT_READ },
 212         { 1, REG_AR_FAULT_ADDR, "AR MULTI-HIT", IOMMU_FAULT_READ },
 213         { 2, REG_AW_FAULT_ADDR, "AW MULTI-HIT", IOMMU_FAULT_WRITE },
 214         { 3, REG_DEFAULT_SLAVE_ADDR, "BUS ERROR", IOMMU_FAULT_READ },
 215         { 4, REG_AR_FAULT_ADDR, "AR SECURITY PROTECTION", IOMMU_FAULT_READ },
 216         { 5, REG_AR_FAULT_ADDR, "AR ACCESS PROTECTION", IOMMU_FAULT_READ },
 217         { 6, REG_AW_FAULT_ADDR, "AW SECURITY PROTECTION", IOMMU_FAULT_WRITE },
 218         { 7, REG_AW_FAULT_ADDR, "AW ACCESS PROTECTION", IOMMU_FAULT_WRITE },
 219 };
 220
 221 static const struct sysmmu_fault_info sysmmu_v5_faults[] = {
 222         { 0, REG_V5_FAULT_AR_VA, "AR PTW", IOMMU_FAULT_READ },
 223         { 1, REG_V5_FAULT_AR_VA, "AR PAGE", IOMMU_FAULT_READ },
 224         { 2, REG_V5_FAULT_AR_VA, "AR MULTI-HIT", IOMMU_FAULT_READ },
 225         { 3, REG_V5_FAULT_AR_VA, "AR ACCESS PROTECTION", IOMMU_FAULT_READ },
 226         { 4, REG_V5_FAULT_AR_VA, "AR SECURITY PROTECTION", IOMMU_FAULT_READ },
 227         { 16, REG_V5_FAULT_AW_VA, "AW PTW", IOMMU_FAULT_WRITE },
 228         { 17, REG_V5_FAULT_AW_VA, "AW PAGE", IOMMU_FAULT_WRITE },
 229         { 18, REG_V5_FAULT_AW_VA, "AW MULTI-HIT", IOMMU_FAULT_WRITE },
 230         { 19, REG_V5_FAULT_AW_VA, "AW ACCESS PROTECTION", IOMMU_FAULT_WRITE },
 231         { 20, REG_V5_FAULT_AW_VA, "AW SECURITY PROTECTION", IOMMU_FAULT_WRITE },
 232 };
 233
 234 /*
 235  * This structure is attached to dev.archdata.iommu of the master device
 236  * on device add, contains a list of SYSMMU controllers defined by device tree,
 237  * which are bound to given master device. It is usually referenced by 'owner'
 238  * pointer.
 239 */
 240 struct exynos_iommu_owner {
 241         struct list_head controllers;   /* list of sysmmu_drvdata.owner_node */
 242         struct iommu_domain *domain;    /* domain this device is attached */
 243         struct mutex rpm_lock;          /* for runtime pm of all sysmmus */
 244 };
 245
 246 /*
 247  * This structure exynos specific generalization of struct iommu_domain.
 248  * It contains list of SYSMMU controllers from all master devices, which has
 249  * been attached to this domain and page tables of IO address space defined by
 250  * it. It is usually referenced by 'domain' pointer.
 251  */
 252 struct exynos_iommu_domain {
 253         struct list_head clients; /* list of sysmmu_drvdata.domain_node */
 254         sysmmu_pte_t *pgtable;  /* lv1 page table, 16KB */
 255         short *lv2entcnt;       /* free lv2 entry counter for each section */
 256         spinlock_t lock;        /* lock for modyfying list of clients */
 257         spinlock_t pgtablelock; /* lock for modifying page table @ pgtable */
 258         struct iommu_domain domain; /* generic domain data structure */
 259 };
 260
 261 /*
 262  * This structure hold all data of a single SYSMMU controller, this includes
 263  * hw resources like registers and clocks, pointers and list nodes to connect
 264  * it to all other structures, internal state and parameters read from device
 265  * tree. It is usually referenced by 'data' pointer.
 266  */
 267 struct sysmmu_drvdata {
 268         struct device *sysmmu;          /* SYSMMU controller device */
 269         struct device *master;          /* master device (owner) */
 270         void __iomem *sfrbase;          /* our registers */
 271         struct clk *clk;                /* SYSMMU's clock */
 272         struct clk *aclk;               /* SYSMMU's aclk clock */
 273         struct clk *pclk;               /* SYSMMU's pclk clock */
 274         struct clk *clk_master;         /* master's device clock */
 275         spinlock_t lock;                /* lock for modyfying state */
 276         bool active;                    /* current status */
 277         struct exynos_iommu_domain *domain; /* domain we belong to */
 278         struct list_head domain_node;   /* node for domain clients list */
 279         struct list_head owner_node;    /* node for owner controllers list */
 280         phys_addr_t pgtable;            /* assigned page table structure */
 281         unsigned int version;           /* our version */
 282
 283         struct iommu_device iommu;      /* IOMMU core handle */
 284 };
 285
 286 static struct exynos_iommu_domain *to_exynos_domain(struct iommu_domain *dom)
 287 {
 288         return container_of(dom, struct exynos_iommu_domain, domain);
 289 }
 290
 291 static void sysmmu_unblock(struct sysmmu_drvdata *data)
 292 {
 293         writel(CTRL_ENABLE, data->sfrbase + REG_MMU_CTRL);
 294 }
 295
 296 static bool sysmmu_block(struct sysmmu_drvdata *data)
 297 {
 298         int i = 120;
 299
 300         writel(CTRL_BLOCK, data->sfrbase + REG_MMU_CTRL);
 301         while ((i > 0) && !(readl(data->sfrbase + REG_MMU_STATUS) & 1))
 302                 --i;
 303
 304         if (!(readl(data->sfrbase + REG_MMU_STATUS) & 1)) {
 305                 sysmmu_unblock(data);
 306                 return false;
 307         }
 308
 309         return true;
 310 }
 311
 312 static void __sysmmu_tlb_invalidate(struct sysmmu_drvdata *data)
 313 {
 314         if (MMU_MAJ_VER(data->version) < 5)
 315                 writel(0x1, data->sfrbase + REG_MMU_FLUSH);
 316         else
 317                 writel(0x1, data->sfrbase + REG_V5_MMU_FLUSH_ALL);
 318 }
 319
 320 static void __sysmmu_tlb_invalidate_entry(struct sysmmu_drvdata *data,
 321                                 sysmmu_iova_t iova, unsigned int num_inv)
 322 {
 323         unsigned int i;
 324
 325         if (MMU_MAJ_VER(data->version) < 5) {
 326                 for (i = 0; i < num_inv; i++) {
 327                         writel((iova & SPAGE_MASK) | 1,
 328                                      data->sfrbase + REG_MMU_FLUSH_ENTRY);
 329                         iova += SPAGE_SIZE;
 330                 }
 331         } else {
 332                 if (num_inv == 1) {
 333                         writel((iova & SPAGE_MASK) | 1,
 334                                      data->sfrbase + REG_V5_MMU_FLUSH_ENTRY);
 335                 } else {
 336                         writel((iova & SPAGE_MASK),
 337                                      data->sfrbase + REG_V5_MMU_FLUSH_START);
 338                         writel((iova & SPAGE_MASK) + (num_inv - 1) * SPAGE_SIZE,
 339                                      data->sfrbase + REG_V5_MMU_FLUSH_END);
 340                         writel(1, data->sfrbase + REG_V5_MMU_FLUSH_RANGE);
 341                 }
 342         }
 343 }
 344
 345 static void __sysmmu_set_ptbase(struct sysmmu_drvdata *data, phys_addr_t pgd)
 346 {
 347         if (MMU_MAJ_VER(data->version) < 5)
 348                 writel(pgd, data->sfrbase + REG_PT_BASE_ADDR);
 349         else
 350                 writel(pgd >> PAGE_SHIFT,
 351                              data->sfrbase + REG_V5_PT_BASE_PFN);
 352
 353         __sysmmu_tlb_invalidate(data);
 354 }
 355
 356 static void __sysmmu_enable_clocks(struct sysmmu_drvdata *data)
 357 {
 358         BUG_ON(clk_prepare_enable(data->clk_master));
 359         BUG_ON(clk_prepare_enable(data->clk));
 360         BUG_ON(clk_prepare_enable(data->pclk));
 361         BUG_ON(clk_prepare_enable(data->aclk));
 362 }
 363
 364 static void __sysmmu_disable_clocks(struct sysmmu_drvdata *data)
 365 {
 366         clk_disable_unprepare(data->aclk);
 367         clk_disable_unprepare(data->pclk);
 368         clk_disable_unprepare(data->clk);
 369         clk_disable_unprepare(data->clk_master);
 370 }
 371
 372 static void __sysmmu_get_version(struct sysmmu_drvdata *data)
 373 {
 374         u32 ver;
 375
 376         __sysmmu_enable_clocks(data);
 377
 378         ver = readl(data->sfrbase + REG_MMU_VERSION);
 379
 380         /* controllers on some SoCs don't report proper version */
 381         if (ver == 0x80000001u)
 382                 data->version = MAKE_MMU_VER(1, 0);
 383         else
 384                 data->version = MMU_RAW_VER(ver);
 385
 386         dev_dbg(data->sysmmu, "hardware version: %d.%d\n",
 387                 MMU_MAJ_VER(data->version), MMU_MIN_VER(data->version));
 388
 389         __sysmmu_disable_clocks(data);
 390 }
 391
 392 static void show_fault_information(struct sysmmu_drvdata *data,
 393                                    const struct sysmmu_fault_info *finfo,
 394                                    sysmmu_iova_t fault_addr)
 395 {
 396         sysmmu_pte_t *ent;
 397
 398         dev_err(data->sysmmu, "%s: %s FAULT occurred at %#x\n",
 399                 dev_name(data->master), finfo->name, fault_addr);
 400         dev_dbg(data->sysmmu, "Page table base: %pa\n", &data->pgtable);
 401         ent = section_entry(phys_to_virt(data->pgtable), fault_addr);
 402         dev_dbg(data->sysmmu, "\tLv1 entry: %#x\n", *ent);
 403         if (lv1ent_page(ent)) {
 404                 ent = page_entry(ent, fault_addr);
 405                 dev_dbg(data->sysmmu, "\t Lv2 entry: %#x\n", *ent);
 406         }
 407 }
 408
 409 static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
 410 {
 411         /* SYSMMU is in blocked state when interrupt occurred. */
 412         struct sysmmu_drvdata *data = dev_id;
 413         const struct sysmmu_fault_info *finfo;
 414         unsigned int i, n, itype;
 415         sysmmu_iova_t fault_addr = -1;
 416         unsigned short reg_status, reg_clear;
 417         int ret = -ENOSYS;
 418
 419         WARN_ON(!data->active);
 420
 421         if (MMU_MAJ_VER(data->version) < 5) {
 422                 reg_status = REG_INT_STATUS;
 423                 reg_clear = REG_INT_CLEAR;
 424                 finfo = sysmmu_faults;
 425                 n = ARRAY_SIZE(sysmmu_faults);
 426         } else {
 427                 reg_status = REG_V5_INT_STATUS;
 428                 reg_clear = REG_V5_INT_CLEAR;
 429                 finfo = sysmmu_v5_faults;
 430                 n = ARRAY_SIZE(sysmmu_v5_faults);
 431         }
 432
 433         spin_lock(&data->lock);
 434
 435         clk_enable(data->clk_master);
 436
 437         itype = __ffs(readl(data->sfrbase + reg_status));
 438         for (i = 0; i < n; i++, finfo++)
 439                 if (finfo->bit == itype)
 440                         break;
 441         /* unknown/unsupported fault */
 442         BUG_ON(i == n);
 443
 444         /* print debug message */
 445         fault_addr = readl(data->sfrbase + finfo->addr_reg);
 446         show_fault_information(data, finfo, fault_addr);
 447
 448         if (data->domain)
 449                 ret = report_iommu_fault(&data->domain->domain,
 450                                         data->master, fault_addr, finfo->type);
 451         /* fault is not recovered by fault handler */
 452         BUG_ON(ret != 0);
 453
 454         writel(1 << itype, data->sfrbase + reg_clear);
 455
 456         sysmmu_unblock(data);
 457
 458         clk_disable(data->clk_master);
 459
 460         spin_unlock(&data->lock);
 461
 462         return IRQ_HANDLED;
 463 }
 464
 465 static void __sysmmu_disable(struct sysmmu_drvdata *data)
 466 {
 467         unsigned long flags;
 468
 469         clk_enable(data->clk_master);
 470
 471         spin_lock_irqsave(&data->lock, flags);
 472         writel(CTRL_DISABLE, data->sfrbase + REG_MMU_CTRL);
 473         writel(0, data->sfrbase + REG_MMU_CFG);
 474         data->active = false;
 475         spin_unlock_irqrestore(&data->lock, flags);
 476
 477         __sysmmu_disable_clocks(data);
 478 }
 479
 480 static void __sysmmu_init_config(struct sysmmu_drvdata *data)
 481 {
 482         unsigned int cfg;
 483
 484         if (data->version <= MAKE_MMU_VER(3, 1))
 485                 cfg = CFG_LRU | CFG_QOS(15);
 486         else if (data->version <= MAKE_MMU_VER(3, 2))
 487                 cfg = CFG_LRU | CFG_QOS(15) | CFG_FLPDCACHE | CFG_SYSSEL;
 488         else
 489                 cfg = CFG_QOS(15) | CFG_FLPDCACHE | CFG_ACGEN;
 490
 491         cfg |= CFG_EAP; /* enable access protection bits check */
 492
 493         writel(cfg, data->sfrbase + REG_MMU_CFG);
 494 }
 495
 496 static void __sysmmu_enable(struct sysmmu_drvdata *data)
 497 {
 498         unsigned long flags;
 499
 500         __sysmmu_enable_clocks(data);
 501
 502         spin_lock_irqsave(&data->lock, flags);
 503         writel(CTRL_BLOCK, data->sfrbase + REG_MMU_CTRL);
 504         __sysmmu_init_config(data);
 505         __sysmmu_set_ptbase(data, data->pgtable);
 506         writel(CTRL_ENABLE, data->sfrbase + REG_MMU_CTRL);
 507         data->active = true;
 508         spin_unlock_irqrestore(&data->lock, flags);
 509
 510         /*
 511          * SYSMMU driver keeps master's clock enabled only for the short
 512          * time, while accessing the registers. For performing address
 513          * translation during DMA transaction it relies on the client
 514          * driver to enable it.
 515          */
 516         clk_disable(data->clk_master);
 517 }
 518
 519 static void sysmmu_tlb_invalidate_flpdcache(struct sysmmu_drvdata *data,
 520                                             sysmmu_iova_t iova)
 521 {
 522         unsigned long flags;
 523
 524         spin_lock_irqsave(&data->lock, flags);
 525         if (data->active && data->version >= MAKE_MMU_VER(3, 3)) {
 526                 clk_enable(data->clk_master);
 527                 if (sysmmu_block(data)) {
 528                         if (data->version >= MAKE_MMU_VER(5, 0))
 529                                 __sysmmu_tlb_invalidate(data);
 530                         else
 531                                 __sysmmu_tlb_invalidate_entry(data, iova, 1);
 532                         sysmmu_unblock(data);
 533                 }
 534                 clk_disable(data->clk_master);
 535         }
 536         spin_unlock_irqrestore(&data->lock, flags);
 537 }
 538
 539 static void sysmmu_tlb_invalidate_entry(struct sysmmu_drvdata *data,
 540                                         sysmmu_iova_t iova, size_t size)
 541 {
 542         unsigned long flags;
 543
 544         spin_lock_irqsave(&data->lock, flags);
 545         if (data->active) {
 546                 unsigned int num_inv = 1;
 547
 548                 clk_enable(data->clk_master);
 549
 550                 /*
 551                  * L2TLB invalidation required
 552                  * 4KB page: 1 invalidation
 553                  * 64KB page: 16 invalidations
 554                  * 1MB page: 64 invalidations
 555                  * because it is set-associative TLB
 556                  * with 8-way and 64 sets.
 557                  * 1MB page can be cached in one of all sets.
 558                  * 64KB page can be one of 16 consecutive sets.
 559                  */
 560                 if (MMU_MAJ_VER(data->version) == 2)
 561                         num_inv = min_t(unsigned int, size / PAGE_SIZE, 64);
 562
 563                 if (sysmmu_block(data)) {
 564                         __sysmmu_tlb_invalidate_entry(data, iova, num_inv);
 565                         sysmmu_unblock(data);
 566                 }
 567                 clk_disable(data->clk_master);
 568         }
 569         spin_unlock_irqrestore(&data->lock, flags);
 570 }
 571
 572 static struct iommu_ops exynos_iommu_ops;
 573
 574 static int __init exynos_sysmmu_probe(struct platform_device *pdev)
 575 {
 576         int irq, ret;
 577         struct device *dev = &pdev->dev;
 578         struct sysmmu_drvdata *data;
 579         struct resource *res;
 580
 581         data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
 582         if (!data)
 583                 return -ENOMEM;
 584
 585         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 586         data->sfrbase = devm_ioremap_resource(dev, res);
 587         if (IS_ERR(data->sfrbase))
 588                 return PTR_ERR(data->sfrbase);
 589
 590         irq = platform_get_irq(pdev, 0);
 591         if (irq <= 0) {
 592                 dev_err(dev, "Unable to find IRQ resource\n");
 593                 return irq;
 594         }
 595
 596         ret = devm_request_irq(dev, irq, exynos_sysmmu_irq, 0,
 597                                 dev_name(dev), data);
 598         if (ret) {
 599                 dev_err(dev, "Unabled to register handler of irq %d\n", irq);
 600                 return ret;
 601         }
 602
 603         data->clk = devm_clk_get(dev, "sysmmu");
 604         if (PTR_ERR(data->clk) == -ENOENT)
 605                 data->clk = NULL;
 606         else if (IS_ERR(data->clk))
 607                 return PTR_ERR(data->clk);
 608
 609         data->aclk = devm_clk_get(dev, "aclk");
 610         if (PTR_ERR(data->aclk) == -ENOENT)
 611                 data->aclk = NULL;
 612         else if (IS_ERR(data->aclk))
 613                 return PTR_ERR(data->aclk);
 614
 615         data->pclk = devm_clk_get(dev, "pclk");
 616         if (PTR_ERR(data->pclk) == -ENOENT)
 617                 data->pclk = NULL;
 618         else if (IS_ERR(data->pclk))
 619                 return PTR_ERR(data->pclk);
 620
 621         if (!data->clk && (!data->aclk || !data->pclk)) {
 622                 dev_err(dev, "Failed to get device clock(s)!\n");
 623                 return -ENOSYS;
 624         }
 625
 626         data->clk_master = devm_clk_get(dev, "master");
 627         if (PTR_ERR(data->clk_master) == -ENOENT)
 628                 data->clk_master = NULL;
 629         else if (IS_ERR(data->clk_master))
 630                 return PTR_ERR(data->clk_master);
 631
 632         data->sysmmu = dev;
 633         spin_lock_init(&data->lock);
 634
 635         ret = iommu_device_sysfs_add(&data->iommu, &pdev->dev, NULL,
 636                                      dev_name(data->sysmmu));
 637         if (ret)
 638                 return ret;
 639
 640         iommu_device_set_ops(&data->iommu, &exynos_iommu_ops);
 641         iommu_device_set_fwnode(&data->iommu, &dev->of_node->fwnode);
 642
 643         ret = iommu_device_register(&data->iommu);
 644         if (ret)
 645                 return ret;
 646
 647         platform_set_drvdata(pdev, data);
 648
 649         __sysmmu_get_version(data);
 650         if (PG_ENT_SHIFT < 0) {
 651                 if (MMU_MAJ_VER(data->version) < 5) {
 652                         PG_ENT_SHIFT = SYSMMU_PG_ENT_SHIFT;
 653                         LV1_PROT = SYSMMU_LV1_PROT;
 654                         LV2_PROT = SYSMMU_LV2_PROT;
 655                 } else {
 656                         PG_ENT_SHIFT = SYSMMU_V5_PG_ENT_SHIFT;
 657                         LV1_PROT = SYSMMU_V5_LV1_PROT;
 658                         LV2_PROT = SYSMMU_V5_LV2_PROT;
 659                 }
 660         }
 661
 662         pm_runtime_enable(dev);
 663
 664         return 0;
 665 }
 666
 667 static int __maybe_unused exynos_sysmmu_suspend(struct device *dev)
 668 {
 669         struct sysmmu_drvdata *data = dev_get_drvdata(dev);
 670         struct device *master = data->master;
 671
 672         if (master) {
 673                 struct exynos_iommu_owner *owner = master->archdata.iommu;
 674
 675                 mutex_lock(&owner->rpm_lock);
 676                 if (data->domain) {
 677                         dev_dbg(data->sysmmu, "saving state\n");
 678                         __sysmmu_disable(data);
 679                 }
 680                 mutex_unlock(&owner->rpm_lock);
 681         }
 682         return 0;
 683 }
 684
 685 static int __maybe_unused exynos_sysmmu_resume(struct device *dev)
 686 {
 687         struct sysmmu_drvdata *data = dev_get_drvdata(dev);
 688         struct device *master = data->master;
 689
 690         if (master) {
 691                 struct exynos_iommu_owner *owner = master->archdata.iommu;
 692
 693                 mutex_lock(&owner->rpm_lock);
 694                 if (data->domain) {
 695                         dev_dbg(data->sysmmu, "restoring state\n");
 696                         __sysmmu_enable(data);
 697                 }
 698                 mutex_unlock(&owner->rpm_lock);
 699         }
 700         return 0;
 701 }
 702
 703 static const struct dev_pm_ops sysmmu_pm_ops = {
 704         SET_RUNTIME_PM_OPS(exynos_sysmmu_suspend, exynos_sysmmu_resume, NULL)
 705         SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
 706                                 pm_runtime_force_resume)
 707 };
 708
 709 static const struct of_device_id sysmmu_of_match[] __initconst = {
 710         { .compatible   = "samsung,exynos-sysmmu", },
 711         { },
 712 };
 713
 714 static struct platform_driver exynos_sysmmu_driver __refdata = {
 715         .probe  = exynos_sysmmu_probe,
 716         .driver = {
 717                 .name           = "exynos-sysmmu",
 718                 .of_match_table = sysmmu_of_match,
 719                 .pm             = &sysmmu_pm_ops,
 720                 .suppress_bind_attrs = true,
 721         }
 722 };
 723
 724 static inline void update_pte(sysmmu_pte_t *ent, sysmmu_pte_t val)
 725 {
 726         dma_sync_single_for_cpu(dma_dev, virt_to_phys(ent), sizeof(*ent),
 727                                 DMA_TO_DEVICE);
 728         *ent = cpu_to_le32(val);
 729         dma_sync_single_for_device(dma_dev, virt_to_phys(ent), sizeof(*ent),
 730                                    DMA_TO_DEVICE);
 731 }
 732
 733 static struct iommu_domain *exynos_iommu_domain_alloc(unsigned type)
 734 {
 735         struct exynos_iommu_domain *domain;
 736         dma_addr_t handle;
 737         int i;
 738
 739         /* Check if correct PTE offsets are initialized */
 740         BUG_ON(PG_ENT_SHIFT < 0 || !dma_dev);
 741
 742         domain = kzalloc(sizeof(*domain), GFP_KERNEL);
 743         if (!domain)
 744                 return NULL;
 745
 746         if (type == IOMMU_DOMAIN_DMA) {
 747                 if (iommu_get_dma_cookie(&domain->domain) != 0)
 748                         goto err_pgtable;
 749         } else if (type != IOMMU_DOMAIN_UNMANAGED) {
 750                 goto err_pgtable;
 751         }
 752
 753         domain->pgtable = (sysmmu_pte_t *)__get_free_pages(GFP_KERNEL, 2);
 754         if (!domain->pgtable)
 755                 goto err_dma_cookie;
 756
 757         domain->lv2entcnt = (short *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, 1);
 758         if (!domain->lv2entcnt)
 759                 goto err_counter;
 760
 761         /* Workaround for System MMU v3.3 to prevent caching 1MiB mapping */
 762         for (i = 0; i < NUM_LV1ENTRIES; i++)
 763                 domain->pgtable[i] = ZERO_LV2LINK;
 764
 765         handle = dma_map_single(dma_dev, domain->pgtable, LV1TABLE_SIZE,
 766                                 DMA_TO_DEVICE);
 767         /* For mapping page table entries we rely on dma == phys */
 768         BUG_ON(handle != virt_to_phys(domain->pgtable));
 769         if (dma_mapping_error(dma_dev, handle))
 770                 goto err_lv2ent;
 771
 772         spin_lock_init(&domain->lock);
 773         spin_lock_init(&domain->pgtablelock);
 774         INIT_LIST_HEAD(&domain->clients);
 775
 776         domain->domain.geometry.aperture_start = 0;
 777         domain->domain.geometry.aperture_end   = ~0UL;
 778         domain->domain.geometry.force_aperture = true;
 779
 780         return &domain->domain;
 781
 782 err_lv2ent:
 783         free_pages((unsigned long)domain->lv2entcnt, 1);
 784 err_counter:
 785         free_pages((unsigned long)domain->pgtable, 2);
 786 err_dma_cookie:
 787         if (type == IOMMU_DOMAIN_DMA)
 788                 iommu_put_dma_cookie(&domain->domain);
 789 err_pgtable:
 790         kfree(domain);
 791         return NULL;
 792 }
 793
 794 static void exynos_iommu_domain_free(struct iommu_domain *iommu_domain)
 795 {
 796         struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
 797         struct sysmmu_drvdata *data, *next;
 798         unsigned long flags;
 799         int i;
 800
 801         WARN_ON(!list_empty(&domain->clients));
 802
 803         spin_lock_irqsave(&domain->lock, flags);
 804
 805         list_for_each_entry_safe(data, next, &domain->clients, domain_node) {
 806                 spin_lock(&data->lock);
 807                 __sysmmu_disable(data);
 808                 data->pgtable = 0;
 809                 data->domain = NULL;
 810                 list_del_init(&data->domain_node);
 811                 spin_unlock(&data->lock);
 812         }
 813
 814         spin_unlock_irqrestore(&domain->lock, flags);
 815
 816         if (iommu_domain->type == IOMMU_DOMAIN_DMA)
 817                 iommu_put_dma_cookie(iommu_domain);
 818
 819         dma_unmap_single(dma_dev, virt_to_phys(domain->pgtable), LV1TABLE_SIZE,
 820                          DMA_TO_DEVICE);
 821
 822         for (i = 0; i < NUM_LV1ENTRIES; i++)
 823                 if (lv1ent_page(domain->pgtable + i)) {
 824                         phys_addr_t base = lv2table_base(domain->pgtable + i);
 825
 826                         dma_unmap_single(dma_dev, base, LV2TABLE_SIZE,
 827                                          DMA_TO_DEVICE);
 828                         kmem_cache_free(lv2table_kmem_cache,
 829                                         phys_to_virt(base));
 830                 }
 831
 832         free_pages((unsigned long)domain->pgtable, 2);
 833         free_pages((unsigned long)domain->lv2entcnt, 1);
 834         kfree(domain);
 835 }
 836
 837 static void exynos_iommu_detach_device(struct iommu_domain *iommu_domain,
 838                                     struct device *dev)
 839 {
 840         struct exynos_iommu_owner *owner = dev->archdata.iommu;
 841         struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
 842         phys_addr_t pagetable = virt_to_phys(domain->pgtable);
 843         struct sysmmu_drvdata *data, *next;
 844         unsigned long flags;
 845
 846         if (!has_sysmmu(dev) || owner->domain != iommu_domain)
 847                 return;
 848
 849         mutex_lock(&owner->rpm_lock);
 850
 851         list_for_each_entry(data, &owner->controllers, owner_node) {
 852                 pm_runtime_get_noresume(data->sysmmu);
 853                 if (pm_runtime_active(data->sysmmu))
 854                         __sysmmu_disable(data);
 855                 pm_runtime_put(data->sysmmu);
 856         }
 857
 858         spin_lock_irqsave(&domain->lock, flags);
 859         list_for_each_entry_safe(data, next, &domain->clients, domain_node) {
 860                 spin_lock(&data->lock);
 861                 data->pgtable = 0;
 862                 data->domain = NULL;
 863                 list_del_init(&data->domain_node);
 864                 spin_unlock(&data->lock);
 865         }
 866         owner->domain = NULL;
 867         spin_unlock_irqrestore(&domain->lock, flags);
 868
 869         mutex_unlock(&owner->rpm_lock);
 870
 871         dev_dbg(dev, "%s: Detached IOMMU with pgtable %pa\n", __func__,
 872                 &pagetable);
 873 }
 874
 875 static int exynos_iommu_attach_device(struct iommu_domain *iommu_domain,
 876                                    struct device *dev)
 877 {
 878         struct exynos_iommu_owner *owner = dev->archdata.iommu;
 879         struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
 880         struct sysmmu_drvdata *data;
 881         phys_addr_t pagetable = virt_to_phys(domain->pgtable);
 882         unsigned long flags;
 883
 884         if (!has_sysmmu(dev))
 885                 return -ENODEV;
 886
 887         if (owner->domain)
 888                 exynos_iommu_detach_device(owner->domain, dev);
 889
 890         mutex_lock(&owner->rpm_lock);
 891
 892         spin_lock_irqsave(&domain->lock, flags);
 893         list_for_each_entry(data, &owner->controllers, owner_node) {
 894                 spin_lock(&data->lock);
 895                 data->pgtable = pagetable;
 896                 data->domain = domain;
 897                 list_add_tail(&data->domain_node, &domain->clients);
 898                 spin_unlock(&data->lock);
 899         }
 900         owner->domain = iommu_domain;
 901         spin_unlock_irqrestore(&domain->lock, flags);
 902
 903         list_for_each_entry(data, &owner->controllers, owner_node) {
 904                 pm_runtime_get_noresume(data->sysmmu);
 905                 if (pm_runtime_active(data->sysmmu))
 906                         __sysmmu_enable(data);
 907                 pm_runtime_put(data->sysmmu);
 908         }
 909
 910         mutex_unlock(&owner->rpm_lock);
 911
 912         dev_dbg(dev, "%s: Attached IOMMU with pgtable %pa\n", __func__,
 913                 &pagetable);
 914
 915         return 0;
 916 }
 917
 918 static sysmmu_pte_t *alloc_lv2entry(struct exynos_iommu_domain *domain,
 919                 sysmmu_pte_t *sent, sysmmu_iova_t iova, short *pgcounter)
 920 {
 921         if (lv1ent_section(sent)) {
 922                 WARN(1, "Trying mapping on %#08x mapped with 1MiB page", iova);
 923                 return ERR_PTR(-EADDRINUSE);
 924         }
 925
 926         if (lv1ent_fault(sent)) {
 927                 dma_addr_t handle;
 928                 sysmmu_pte_t *pent;
 929                 bool need_flush_flpd_cache = lv1ent_zero(sent);
 930
 931                 pent = kmem_cache_zalloc(lv2table_kmem_cache, GFP_ATOMIC);
 932                 BUG_ON((uintptr_t)pent & (LV2TABLE_SIZE - 1));
 933                 if (!pent)
 934                         return ERR_PTR(-ENOMEM);
 935
 936                 update_pte(sent, mk_lv1ent_page(virt_to_phys(pent)));
 937                 kmemleak_ignore(pent);
 938                 *pgcounter = NUM_LV2ENTRIES;
 939                 handle = dma_map_single(dma_dev, pent, LV2TABLE_SIZE,
 940                                         DMA_TO_DEVICE);
 941                 if (dma_mapping_error(dma_dev, handle)) {
 942                         kmem_cache_free(lv2table_kmem_cache, pent);
 943                         return ERR_PTR(-EADDRINUSE);
 944                 }
 945
 946                 /*
 947                  * If pre-fetched SLPD is a faulty SLPD in zero_l2_table,
 948                  * FLPD cache may cache the address of zero_l2_table. This
 949                  * function replaces the zero_l2_table with new L2 page table
 950                  * to write valid mappings.
 951                  * Accessing the valid area may cause page fault since FLPD
 952                  * cache may still cache zero_l2_table for the valid area
 953                  * instead of new L2 page table that has the mapping
 954                  * information of the valid area.
 955                  * Thus any replacement of zero_l2_table with other valid L2
 956                  * page table must involve FLPD cache invalidation for System
 957                  * MMU v3.3.
 958                  * FLPD cache invalidation is performed with TLB invalidation
 959                  * by VPN without blocking. It is safe to invalidate TLB without
 960                  * blocking because the target address of TLB invalidation is
 961                  * not currently mapped.
 962                  */
 963                 if (need_flush_flpd_cache) {
 964                         struct sysmmu_drvdata *data;
 965
 966                         spin_lock(&domain->lock);
 967                         list_for_each_entry(data, &domain->clients, domain_node)
 968                                 sysmmu_tlb_invalidate_flpdcache(data, iova);
 969                         spin_unlock(&domain->lock);
 970                 }
 971         }
 972
 973         return page_entry(sent, iova);
 974 }
 975
 976 static int lv1set_section(struct exynos_iommu_domain *domain,
 977                           sysmmu_pte_t *sent, sysmmu_iova_t iova,
 978                           phys_addr_t paddr, int prot, short *pgcnt)
 979 {
 980         if (lv1ent_section(sent)) {
 981                 WARN(1, "Trying mapping on 1MiB@%#08x that is mapped",
 982                         iova);
 983                 return -EADDRINUSE;
 984         }
 985
 986         if (lv1ent_page(sent)) {
 987                 if (*pgcnt != NUM_LV2ENTRIES) {
 988                         WARN(1, "Trying mapping on 1MiB@%#08x that is mapped",
 989                                 iova);
 990                         return -EADDRINUSE;
 991                 }
 992
 993                 kmem_cache_free(lv2table_kmem_cache, page_entry(sent, 0));
 994                 *pgcnt = 0;
 995         }
 996
 997         update_pte(sent, mk_lv1ent_sect(paddr, prot));
 998
 999         spin_lock(&domain->lock);
1000         if (lv1ent_page_zero(sent)) {
1001                 struct sysmmu_drvdata *data;
1002                 /*
1003                  * Flushing FLPD cache in System MMU v3.3 that may cache a FLPD
1004                  * entry by speculative prefetch of SLPD which has no mapping.
1005                  */
1006                 list_for_each_entry(data, &domain->clients, domain_node)
1007                         sysmmu_tlb_invalidate_flpdcache(data, iova);
1008         }
1009         spin_unlock(&domain->lock);
1010
1011         return 0;
1012 }
1013
1014 static int lv2set_page(sysmmu_pte_t *pent, phys_addr_t paddr, size_t size,
1015                        int prot, short *pgcnt)
1016 {
1017         if (size == SPAGE_SIZE) {
1018                 if (WARN_ON(!lv2ent_fault(pent)))
1019                         return -EADDRINUSE;
1020
1021                 update_pte(pent, mk_lv2ent_spage(paddr, prot));
1022                 *pgcnt -= 1;
1023         } else { /* size == LPAGE_SIZE */
1024                 int i;
1025                 dma_addr_t pent_base = virt_to_phys(pent);
1026
1027                 dma_sync_single_for_cpu(dma_dev, pent_base,
1028                                         sizeof(*pent) * SPAGES_PER_LPAGE,
1029                                         DMA_TO_DEVICE);
1030                 for (i = 0; i < SPAGES_PER_LPAGE; i++, pent++) {
1031                         if (WARN_ON(!lv2ent_fault(pent))) {
1032                                 if (i > 0)
1033                                         memset(pent - i, 0, sizeof(*pent) * i);
1034                                 return -EADDRINUSE;
1035                         }
1036
1037                         *pent = mk_lv2ent_lpage(paddr, prot);
1038                 }
1039                 dma_sync_single_for_device(dma_dev, pent_base,
1040                                            sizeof(*pent) * SPAGES_PER_LPAGE,
1041                                            DMA_TO_DEVICE);
1042                 *pgcnt -= SPAGES_PER_LPAGE;
1043         }
1044
1045         return 0;
1046 }
1047
1048 /*
1049  * *CAUTION* to the I/O virtual memory managers that support exynos-iommu:
1050  *
1051  * System MMU v3.x has advanced logic to improve address translation
1052  * performance with caching more page table entries by a page table walk.
1053  * However, the logic has a bug that while caching faulty page table entries,
1054  * System MMU reports page fault if the cached fault entry is hit even though
1055  * the fault entry is updated to a valid entry after the entry is cached.
1056  * To prevent caching faulty page table entries which may be updated to valid
1057  * entries later, the virtual memory manager should care about the workaround
1058  * for the problem. The following describes the workaround.
1059  *
1060  * Any two consecutive I/O virtual address regions must have a hole of 128KiB
1061  * at maximum to prevent misbehavior of System MMU 3.x (workaround for h/w bug).
1062  *
1063  * Precisely, any start address of I/O virtual region must be aligned with
1064  * the following sizes for System MMU v3.1 and v3.2.
1065  * System MMU v3.1: 128KiB
1066  * System MMU v3.2: 256KiB
1067  *
1068  * Because System MMU v3.3 caches page table entries more aggressively, it needs
1069  * more workarounds.
1070  * - Any two consecutive I/O virtual regions must have a hole of size larger
1071  *   than or equal to 128KiB.
1072  * - Start address of an I/O virtual region must be aligned by 128KiB.
1073  */
1074 static int exynos_iommu_map(struct iommu_domain *iommu_domain,
1075                             unsigned long l_iova, phys_addr_t paddr, size_t size,
1076                             int prot)
1077 {
1078         struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
1079         sysmmu_pte_t *entry;
1080         sysmmu_iova_t iova = (sysmmu_iova_t)l_iova;
1081         unsigned long flags;
1082         int ret = -ENOMEM;
1083
1084         BUG_ON(domain->pgtable == NULL);
1085         prot &= SYSMMU_SUPPORTED_PROT_BITS;
1086
1087         spin_lock_irqsave(&domain->pgtablelock, flags);
1088
1089         entry = section_entry(domain->pgtable, iova);
1090
1091         if (size == SECT_SIZE) {
1092                 ret = lv1set_section(domain, entry, iova, paddr, prot,
1093                                      &domain->lv2entcnt[lv1ent_offset(iova)]);
1094         } else {
1095                 sysmmu_pte_t *pent;
1096
1097                 pent = alloc_lv2entry(domain, entry, iova,
1098                                       &domain->lv2entcnt[lv1ent_offset(iova)]);
1099
1100                 if (IS_ERR(pent))
1101                         ret = PTR_ERR(pent);
1102                 else
1103                         ret = lv2set_page(pent, paddr, size, prot,
1104                                        &domain->lv2entcnt[lv1ent_offset(iova)]);
1105         }
1106
1107         if (ret)
1108                 pr_err("%s: Failed(%d) to map %#zx bytes @ %#x\n",
1109                         __func__, ret, size, iova);
1110
1111         spin_unlock_irqrestore(&domain->pgtablelock, flags);
1112
1113         return ret;
1114 }
1115
1116 static void exynos_iommu_tlb_invalidate_entry(struct exynos_iommu_domain *domain,
1117                                               sysmmu_iova_t iova, size_t size)
1118 {
1119         struct sysmmu_drvdata *data;
1120         unsigned long flags;
1121
1122         spin_lock_irqsave(&domain->lock, flags);
1123
1124         list_for_each_entry(data, &domain->clients, domain_node)
1125                 sysmmu_tlb_invalidate_entry(data, iova, size);
1126
1127         spin_unlock_irqrestore(&domain->lock, flags);
1128 }
1129
1130 static size_t exynos_iommu_unmap(struct iommu_domain *iommu_domain,
1131                                  unsigned long l_iova, size_t size)
1132 {
1133         struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
1134         sysmmu_iova_t iova = (sysmmu_iova_t)l_iova;
1135         sysmmu_pte_t *ent;
1136         size_t err_pgsize;
1137         unsigned long flags;
1138
1139         BUG_ON(domain->pgtable == NULL);
1140
1141         spin_lock_irqsave(&domain->pgtablelock, flags);
1142
1143         ent = section_entry(domain->pgtable, iova);
1144
1145         if (lv1ent_section(ent)) {
1146                 if (WARN_ON(size < SECT_SIZE)) {
1147                         err_pgsize = SECT_SIZE;
1148                         goto err;
1149                 }
1150
1151                 /* workaround for h/w bug in System MMU v3.3 */
1152                 update_pte(ent, ZERO_LV2LINK);
1153                 size = SECT_SIZE;
1154                 goto done;
1155         }
1156
1157         if (unlikely(lv1ent_fault(ent))) {
1158                 if (size > SECT_SIZE)
1159                         size = SECT_SIZE;
1160                 goto done;
1161         }
1162
1163         /* lv1ent_page(sent) == true here */
1164
1165         ent = page_entry(ent, iova);
1166
1167         if (unlikely(lv2ent_fault(ent))) {
1168                 size = SPAGE_SIZE;
1169                 goto done;
1170         }
1171
1172         if (lv2ent_small(ent)) {
1173                 update_pte(ent, 0);
1174                 size = SPAGE_SIZE;
1175                 domain->lv2entcnt[lv1ent_offset(iova)] += 1;
1176                 goto done;
1177         }
1178
1179         /* lv1ent_large(ent) == true here */
1180         if (WARN_ON(size < LPAGE_SIZE)) {
1181                 err_pgsize = LPAGE_SIZE;
1182                 goto err;
1183         }
1184
1185         dma_sync_single_for_cpu(dma_dev, virt_to_phys(ent),
1186                                 sizeof(*ent) * SPAGES_PER_LPAGE,
1187                                 DMA_TO_DEVICE);
1188         memset(ent, 0, sizeof(*ent) * SPAGES_PER_LPAGE);
1189         dma_sync_single_for_device(dma_dev, virt_to_phys(ent),
1190                                    sizeof(*ent) * SPAGES_PER_LPAGE,
1191                                    DMA_TO_DEVICE);
1192         size = LPAGE_SIZE;
1193         domain->lv2entcnt[lv1ent_offset(iova)] += SPAGES_PER_LPAGE;
1194 done:
1195         spin_unlock_irqrestore(&domain->pgtablelock, flags);
1196
1197         exynos_iommu_tlb_invalidate_entry(domain, iova, size);
1198
1199         return size;
1200 err:
1201         spin_unlock_irqrestore(&domain->pgtablelock, flags);
1202
1203         pr_err("%s: Failed: size(%#zx) @ %#x is smaller than page size %#zx\n",
1204                 __func__, size, iova, err_pgsize);
1205
1206         return 0;
1207 }
1208
1209 static phys_addr_t exynos_iommu_iova_to_phys(struct iommu_domain *iommu_domain,
1210                                           dma_addr_t iova)
1211 {
1212         struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
1213         sysmmu_pte_t *entry;
1214         unsigned long flags;
1215         phys_addr_t phys = 0;
1216
1217         spin_lock_irqsave(&domain->pgtablelock, flags);
1218
1219         entry = section_entry(domain->pgtable, iova);
1220
1221         if (lv1ent_section(entry)) {
1222                 phys = section_phys(entry) + section_offs(iova);
1223         } else if (lv1ent_page(entry)) {
1224                 entry = page_entry(entry, iova);
1225
1226                 if (lv2ent_large(entry))
1227                         phys = lpage_phys(entry) + lpage_offs(iova);
1228                 else if (lv2ent_small(entry))
1229                         phys = spage_phys(entry) + spage_offs(iova);
1230         }
1231
1232         spin_unlock_irqrestore(&domain->pgtablelock, flags);
1233
1234         return phys;
1235 }
1236
1237 static struct iommu_group *get_device_iommu_group(struct device *dev)
1238 {
1239         struct iommu_group *group;
1240
1241         group = iommu_group_get(dev);
1242         if (!group)
1243                 group = iommu_group_alloc();
1244
1245         return group;
1246 }
1247
1248 static int exynos_iommu_add_device(struct device *dev)
1249 {
1250         struct iommu_group *group;
1251
1252         if (!has_sysmmu(dev))
1253                 return -ENODEV;
1254
1255         group = iommu_group_get_for_dev(dev);
1256
1257         if (IS_ERR(group))
1258                 return PTR_ERR(group);
1259
1260         iommu_group_put(group);
1261
1262         return 0;
1263 }
1264
1265 static void exynos_iommu_remove_device(struct device *dev)
1266 {
1267         struct exynos_iommu_owner *owner = dev->archdata.iommu;
1268
1269         if (!has_sysmmu(dev))
1270                 return;
1271
1272         if (owner->domain) {
1273                 struct iommu_group *group = iommu_group_get(dev);
1274
1275                 if (group) {
1276                         WARN_ON(owner->domain !=
1277                                 iommu_group_default_domain(group));
1278                         exynos_iommu_detach_device(owner->domain, dev);
1279                         iommu_group_put(group);
1280                 }
1281         }
1282         iommu_group_remove_device(dev);
1283 }
1284
1285 static int exynos_iommu_of_xlate(struct device *dev,
1286                                  struct of_phandle_args *spec)
1287 {
1288         struct exynos_iommu_owner *owner = dev->archdata.iommu;
1289         struct platform_device *sysmmu = of_find_device_by_node(spec->np);
1290         struct sysmmu_drvdata *data, *entry;
1291
1292         if (!sysmmu)
1293                 return -ENODEV;
1294
1295         data = platform_get_drvdata(sysmmu);
1296         if (!data)
1297                 return -ENODEV;
1298
1299         if (!owner) {
1300                 owner = kzalloc(sizeof(*owner), GFP_KERNEL);
1301                 if (!owner)
1302                         return -ENOMEM;
1303
1304                 INIT_LIST_HEAD(&owner->controllers);
1305                 mutex_init(&owner->rpm_lock);
1306                 dev->archdata.iommu = owner;
1307         }
1308
1309         list_for_each_entry(entry, &owner->controllers, owner_node)
1310                 if (entry == data)
1311                         return 0;
1312
1313         list_add_tail(&data->owner_node, &owner->controllers);
1314         data->master = dev;
1315
1316         /*
1317          * SYSMMU will be runtime activated via device link (dependency) to its
1318          * master device, so there are no direct calls to pm_runtime_get/put
1319          * in this driver.
1320          */
1321         device_link_add(dev, data->sysmmu, DL_FLAG_PM_RUNTIME);
1322
1323         return 0;
1324 }
1325
1326 static struct iommu_ops exynos_iommu_ops = {
1327         .domain_alloc = exynos_iommu_domain_alloc,
1328         .domain_free = exynos_iommu_domain_free,
1329         .attach_dev = exynos_iommu_attach_device,
1330         .detach_dev = exynos_iommu_detach_device,
1331         .map = exynos_iommu_map,
1332         .unmap = exynos_iommu_unmap,
1333         .map_sg = default_iommu_map_sg,
1334         .iova_to_phys = exynos_iommu_iova_to_phys,
1335         .device_group = get_device_iommu_group,
1336         .add_device = exynos_iommu_add_device,
1337         .remove_device = exynos_iommu_remove_device,
1338         .pgsize_bitmap = SECT_SIZE | LPAGE_SIZE | SPAGE_SIZE,
1339         .of_xlate = exynos_iommu_of_xlate,
1340 };
1341
1342 static bool init_done;
1343
1344 static int __init exynos_iommu_init(void)
1345 {
1346         int ret;
1347
1348         lv2table_kmem_cache = kmem_cache_create("exynos-iommu-lv2table",
1349                                 LV2TABLE_SIZE, LV2TABLE_SIZE, 0, NULL);
1350         if (!lv2table_kmem_cache) {
1351                 pr_err("%s: Failed to create kmem cache\n", __func__);
1352                 return -ENOMEM;
1353         }
1354
1355         ret = platform_driver_register(&exynos_sysmmu_driver);
1356         if (ret) {
1357                 pr_err("%s: Failed to register driver\n", __func__);
1358                 goto err_reg_driver;
1359         }
1360
1361         zero_lv2_table = kmem_cache_zalloc(lv2table_kmem_cache, GFP_KERNEL);
1362         if (zero_lv2_table == NULL) {
1363                 pr_err("%s: Failed to allocate zero level2 page table\n",
1364                         __func__);
1365                 ret = -ENOMEM;
1366                 goto err_zero_lv2;
1367         }
1368
1369         ret = bus_set_iommu(&platform_bus_type, &exynos_iommu_ops);
1370         if (ret) {
1371                 pr_err("%s: Failed to register exynos-iommu driver.\n",
1372                                                                 __func__);
1373                 goto err_set_iommu;
1374         }
1375
1376         init_done = true;
1377
1378         return 0;
1379 err_set_iommu:
1380         kmem_cache_free(lv2table_kmem_cache, zero_lv2_table);
1381 err_zero_lv2:
1382         platform_driver_unregister(&exynos_sysmmu_driver);
1383 err_reg_driver:
1384         kmem_cache_destroy(lv2table_kmem_cache);
1385         return ret;
1386 }
1387
1388 static int __init exynos_iommu_of_setup(struct device_node *np)
1389 {
1390         struct platform_device *pdev;
1391
1392         if (!init_done)
1393                 exynos_iommu_init();
1394
1395         pdev = of_platform_device_create(np, NULL, platform_bus_type.dev_root);
1396         if (!pdev)
1397                 return -ENODEV;
1398
1399         /*
1400          * use the first registered sysmmu device for performing
1401          * dma mapping operations on iommu page tables (cpu cache flush)
1402          */
1403         if (!dma_dev)
1404                 dma_dev = &pdev->dev;
1405
1406         return 0;
1407 }
1408
1409 IOMMU_OF_DECLARE(exynos_iommu_of, "samsung,exynos-sysmmu",
1410                  exynos_iommu_of_setup);