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