// SPDX-License-Identifier: GPL-2.0-only /* * Copyright (c) 2011,2016 Samsung Electronics Co., Ltd. * http://www.samsung.com */ #ifdef CONFIG_EXYNOS_IOMMU_DEBUG #define DEBUG #endif #include #include #include #include #include #include #include #include #include #include #include #include #include typedef u32 sysmmu_iova_t; typedef u32 sysmmu_pte_t; /* We do not consider super section mapping (16MB) */ #define SECT_ORDER 20 #define LPAGE_ORDER 16 #define SPAGE_ORDER 12 #define SECT_SIZE (1 << SECT_ORDER) #define LPAGE_SIZE (1 << LPAGE_ORDER) #define SPAGE_SIZE (1 << SPAGE_ORDER) #define SECT_MASK (~(SECT_SIZE - 1)) #define LPAGE_MASK (~(LPAGE_SIZE - 1)) #define SPAGE_MASK (~(SPAGE_SIZE - 1)) #define lv1ent_fault(sent) ((*(sent) == ZERO_LV2LINK) || \ ((*(sent) & 3) == 0) || ((*(sent) & 3) == 3)) #define lv1ent_zero(sent) (*(sent) == ZERO_LV2LINK) #define lv1ent_page_zero(sent) ((*(sent) & 3) == 1) #define lv1ent_page(sent) ((*(sent) != ZERO_LV2LINK) && \ ((*(sent) & 3) == 1)) #define lv1ent_section(sent) ((*(sent) & 3) == 2) #define lv2ent_fault(pent) ((*(pent) & 3) == 0) #define lv2ent_small(pent) ((*(pent) & 2) == 2) #define lv2ent_large(pent) ((*(pent) & 3) == 1) /* * v1.x - v3.x SYSMMU supports 32bit physical and 32bit virtual address spaces * v5.0 introduced support for 36bit physical address space by shifting * all page entry values by 4 bits. * All SYSMMU controllers in the system support the address spaces of the same * size, so PG_ENT_SHIFT can be initialized on first SYSMMU probe to proper * value (0 or 4). */ static short PG_ENT_SHIFT = -1; #define SYSMMU_PG_ENT_SHIFT 0 #define SYSMMU_V5_PG_ENT_SHIFT 4 static const sysmmu_pte_t *LV1_PROT; static const sysmmu_pte_t SYSMMU_LV1_PROT[] = { ((0 << 15) | (0 << 10)), /* no access */ ((1 << 15) | (1 << 10)), /* IOMMU_READ only */ ((0 << 15) | (1 << 10)), /* IOMMU_WRITE not supported, use read/write */ ((0 << 15) | (1 << 10)), /* IOMMU_READ | IOMMU_WRITE */ }; static const sysmmu_pte_t SYSMMU_V5_LV1_PROT[] = { (0 << 4), /* no access */ (1 << 4), /* IOMMU_READ only */ (2 << 4), /* IOMMU_WRITE only */ (3 << 4), /* IOMMU_READ | IOMMU_WRITE */ }; static const sysmmu_pte_t *LV2_PROT; static const sysmmu_pte_t SYSMMU_LV2_PROT[] = { ((0 << 9) | (0 << 4)), /* no access */ ((1 << 9) | (1 << 4)), /* IOMMU_READ only */ ((0 << 9) | (1 << 4)), /* IOMMU_WRITE not supported, use read/write */ ((0 << 9) | (1 << 4)), /* IOMMU_READ | IOMMU_WRITE */ }; static const sysmmu_pte_t SYSMMU_V5_LV2_PROT[] = { (0 << 2), /* no access */ (1 << 2), /* IOMMU_READ only */ (2 << 2), /* IOMMU_WRITE only */ (3 << 2), /* IOMMU_READ | IOMMU_WRITE */ }; #define SYSMMU_SUPPORTED_PROT_BITS (IOMMU_READ | IOMMU_WRITE) #define sect_to_phys(ent) (((phys_addr_t) ent) << PG_ENT_SHIFT) #define section_phys(sent) (sect_to_phys(*(sent)) & SECT_MASK) #define section_offs(iova) (iova & (SECT_SIZE - 1)) #define lpage_phys(pent) (sect_to_phys(*(pent)) & LPAGE_MASK) #define lpage_offs(iova) (iova & (LPAGE_SIZE - 1)) #define spage_phys(pent) (sect_to_phys(*(pent)) & SPAGE_MASK) #define spage_offs(iova) (iova & (SPAGE_SIZE - 1)) #define NUM_LV1ENTRIES 4096 #define NUM_LV2ENTRIES (SECT_SIZE / SPAGE_SIZE) static u32 lv1ent_offset(sysmmu_iova_t iova) { return iova >> SECT_ORDER; } static u32 lv2ent_offset(sysmmu_iova_t iova) { return (iova >> SPAGE_ORDER) & (NUM_LV2ENTRIES - 1); } #define LV1TABLE_SIZE (NUM_LV1ENTRIES * sizeof(sysmmu_pte_t)) #define LV2TABLE_SIZE (NUM_LV2ENTRIES * sizeof(sysmmu_pte_t)) #define SPAGES_PER_LPAGE (LPAGE_SIZE / SPAGE_SIZE) #define lv2table_base(sent) (sect_to_phys(*(sent) & 0xFFFFFFC0)) #define mk_lv1ent_sect(pa, prot) ((pa >> PG_ENT_SHIFT) | LV1_PROT[prot] | 2) #define mk_lv1ent_page(pa) ((pa >> PG_ENT_SHIFT) | 1) #define mk_lv2ent_lpage(pa, prot) ((pa >> PG_ENT_SHIFT) | LV2_PROT[prot] | 1) #define mk_lv2ent_spage(pa, prot) ((pa >> PG_ENT_SHIFT) | LV2_PROT[prot] | 2) #define CTRL_ENABLE 0x5 #define CTRL_BLOCK 0x7 #define CTRL_DISABLE 0x0 #define CFG_LRU 0x1 #define CFG_EAP (1 << 2) #define CFG_QOS(n) ((n & 0xF) << 7) #define CFG_ACGEN (1 << 24) /* System MMU 3.3 only */ #define CFG_SYSSEL (1 << 22) /* System MMU 3.2 only */ #define CFG_FLPDCACHE (1 << 20) /* System MMU 3.2+ only */ /* common registers */ #define REG_MMU_CTRL 0x000 #define REG_MMU_CFG 0x004 #define REG_MMU_STATUS 0x008 #define REG_MMU_VERSION 0x034 #define MMU_MAJ_VER(val) ((val) >> 7) #define MMU_MIN_VER(val) ((val) & 0x7F) #define MMU_RAW_VER(reg) (((reg) >> 21) & ((1 << 11) - 1)) /* 11 bits */ #define MAKE_MMU_VER(maj, min) ((((maj) & 0xF) << 7) | ((min) & 0x7F)) /* v1.x - v3.x registers */ #define REG_MMU_FLUSH 0x00C #define REG_MMU_FLUSH_ENTRY 0x010 #define REG_PT_BASE_ADDR 0x014 #define REG_INT_STATUS 0x018 #define REG_INT_CLEAR 0x01C #define REG_PAGE_FAULT_ADDR 0x024 #define REG_AW_FAULT_ADDR 0x028 #define REG_AR_FAULT_ADDR 0x02C #define REG_DEFAULT_SLAVE_ADDR 0x030 /* v5.x registers */ #define REG_V5_PT_BASE_PFN 0x00C #define REG_V5_MMU_FLUSH_ALL 0x010 #define REG_V5_MMU_FLUSH_ENTRY 0x014 #define REG_V5_MMU_FLUSH_RANGE 0x018 #define REG_V5_MMU_FLUSH_START 0x020 #define REG_V5_MMU_FLUSH_END 0x024 #define REG_V5_INT_STATUS 0x060 #define REG_V5_INT_CLEAR 0x064 #define REG_V5_FAULT_AR_VA 0x070 #define REG_V5_FAULT_AW_VA 0x080 #define has_sysmmu(dev) (dev_iommu_priv_get(dev) != NULL) static struct device *dma_dev; static struct kmem_cache *lv2table_kmem_cache; static sysmmu_pte_t *zero_lv2_table; #define ZERO_LV2LINK mk_lv1ent_page(virt_to_phys(zero_lv2_table)) static sysmmu_pte_t *section_entry(sysmmu_pte_t *pgtable, sysmmu_iova_t iova) { return pgtable + lv1ent_offset(iova); } static sysmmu_pte_t *page_entry(sysmmu_pte_t *sent, sysmmu_iova_t iova) { return (sysmmu_pte_t *)phys_to_virt( lv2table_base(sent)) + lv2ent_offset(iova); } /* * IOMMU fault information register */ struct sysmmu_fault_info { unsigned int bit; /* bit number in STATUS register */ unsigned short addr_reg; /* register to read VA fault address */ const char *name; /* human readable fault name */ unsigned int type; /* fault type for report_iommu_fault */ }; static const struct sysmmu_fault_info sysmmu_faults[] = { { 0, REG_PAGE_FAULT_ADDR, "PAGE", IOMMU_FAULT_READ }, { 1, REG_AR_FAULT_ADDR, "AR MULTI-HIT", IOMMU_FAULT_READ }, { 2, REG_AW_FAULT_ADDR, "AW MULTI-HIT", IOMMU_FAULT_WRITE }, { 3, REG_DEFAULT_SLAVE_ADDR, "BUS ERROR", IOMMU_FAULT_READ }, { 4, REG_AR_FAULT_ADDR, "AR SECURITY PROTECTION", IOMMU_FAULT_READ }, { 5, REG_AR_FAULT_ADDR, "AR ACCESS PROTECTION", IOMMU_FAULT_READ }, { 6, REG_AW_FAULT_ADDR, "AW SECURITY PROTECTION", IOMMU_FAULT_WRITE }, { 7, REG_AW_FAULT_ADDR, "AW ACCESS PROTECTION", IOMMU_FAULT_WRITE }, }; static const struct sysmmu_fault_info sysmmu_v5_faults[] = { { 0, REG_V5_FAULT_AR_VA, "AR PTW", IOMMU_FAULT_READ }, { 1, REG_V5_FAULT_AR_VA, "AR PAGE", IOMMU_FAULT_READ }, { 2, REG_V5_FAULT_AR_VA, "AR MULTI-HIT", IOMMU_FAULT_READ }, { 3, REG_V5_FAULT_AR_VA, "AR ACCESS PROTECTION", IOMMU_FAULT_READ }, { 4, REG_V5_FAULT_AR_VA, "AR SECURITY PROTECTION", IOMMU_FAULT_READ }, { 16, REG_V5_FAULT_AW_VA, "AW PTW", IOMMU_FAULT_WRITE }, { 17, REG_V5_FAULT_AW_VA, "AW PAGE", IOMMU_FAULT_WRITE }, { 18, REG_V5_FAULT_AW_VA, "AW MULTI-HIT", IOMMU_FAULT_WRITE }, { 19, REG_V5_FAULT_AW_VA, "AW ACCESS PROTECTION", IOMMU_FAULT_WRITE }, { 20, REG_V5_FAULT_AW_VA, "AW SECURITY PROTECTION", IOMMU_FAULT_WRITE }, }; /* * This structure is attached to dev->iommu->priv of the master device * on device add, contains a list of SYSMMU controllers defined by device tree, * which are bound to given master device. It is usually referenced by 'owner' * pointer. */ struct exynos_iommu_owner { struct list_head controllers; /* list of sysmmu_drvdata.owner_node */ struct iommu_domain *domain; /* domain this device is attached */ struct mutex rpm_lock; /* for runtime pm of all sysmmus */ }; /* * This structure exynos specific generalization of struct iommu_domain. * It contains list of SYSMMU controllers from all master devices, which has * been attached to this domain and page tables of IO address space defined by * it. It is usually referenced by 'domain' pointer. */ struct exynos_iommu_domain { struct list_head clients; /* list of sysmmu_drvdata.domain_node */ sysmmu_pte_t *pgtable; /* lv1 page table, 16KB */ short *lv2entcnt; /* free lv2 entry counter for each section */ spinlock_t lock; /* lock for modyfying list of clients */ spinlock_t pgtablelock; /* lock for modifying page table @ pgtable */ struct iommu_domain domain; /* generic domain data structure */ }; /* * This structure hold all data of a single SYSMMU controller, this includes * hw resources like registers and clocks, pointers and list nodes to connect * it to all other structures, internal state and parameters read from device * tree. It is usually referenced by 'data' pointer. */ struct sysmmu_drvdata { struct device *sysmmu; /* SYSMMU controller device */ struct device *master; /* master device (owner) */ struct device_link *link; /* runtime PM link to master */ void __iomem *sfrbase; /* our registers */ struct clk *clk; /* SYSMMU's clock */ struct clk *aclk; /* SYSMMU's aclk clock */ struct clk *pclk; /* SYSMMU's pclk clock */ struct clk *clk_master; /* master's device clock */ spinlock_t lock; /* lock for modyfying state */ bool active; /* current status */ struct exynos_iommu_domain *domain; /* domain we belong to */ struct list_head domain_node; /* node for domain clients list */ struct list_head owner_node; /* node for owner controllers list */ phys_addr_t pgtable; /* assigned page table structure */ unsigned int version; /* our version */ struct iommu_device iommu; /* IOMMU core handle */ }; static struct exynos_iommu_domain *to_exynos_domain(struct iommu_domain *dom) { return container_of(dom, struct exynos_iommu_domain, domain); } static void sysmmu_unblock(struct sysmmu_drvdata *data) { writel(CTRL_ENABLE, data->sfrbase + REG_MMU_CTRL); } static bool sysmmu_block(struct sysmmu_drvdata *data) { int i = 120; writel(CTRL_BLOCK, data->sfrbase + REG_MMU_CTRL); while ((i > 0) && !(readl(data->sfrbase + REG_MMU_STATUS) & 1)) --i; if (!(readl(data->sfrbase + REG_MMU_STATUS) & 1)) { sysmmu_unblock(data); return false; } return true; } static void __sysmmu_tlb_invalidate(struct sysmmu_drvdata *data) { if (MMU_MAJ_VER(data->version) < 5) writel(0x1, data->sfrbase + REG_MMU_FLUSH); else writel(0x1, data->sfrbase + REG_V5_MMU_FLUSH_ALL); } static void __sysmmu_tlb_invalidate_entry(struct sysmmu_drvdata *data, sysmmu_iova_t iova, unsigned int num_inv) { unsigned int i; if (MMU_MAJ_VER(data->version) < 5) { for (i = 0; i < num_inv; i++) { writel((iova & SPAGE_MASK) | 1, data->sfrbase + REG_MMU_FLUSH_ENTRY); iova += SPAGE_SIZE; } } else { if (num_inv == 1) { writel((iova & SPAGE_MASK) | 1, data->sfrbase + REG_V5_MMU_FLUSH_ENTRY); } else { writel((iova & SPAGE_MASK), data->sfrbase + REG_V5_MMU_FLUSH_START); writel((iova & SPAGE_MASK) + (num_inv - 1) * SPAGE_SIZE, data->sfrbase + REG_V5_MMU_FLUSH_END); writel(1, data->sfrbase + REG_V5_MMU_FLUSH_RANGE); } } } static void __sysmmu_set_ptbase(struct sysmmu_drvdata *data, phys_addr_t pgd) { if (MMU_MAJ_VER(data->version) < 5) writel(pgd, data->sfrbase + REG_PT_BASE_ADDR); else writel(pgd >> PAGE_SHIFT, data->sfrbase + REG_V5_PT_BASE_PFN); __sysmmu_tlb_invalidate(data); } static void __sysmmu_enable_clocks(struct sysmmu_drvdata *data) { BUG_ON(clk_prepare_enable(data->clk_master)); BUG_ON(clk_prepare_enable(data->clk)); BUG_ON(clk_prepare_enable(data->pclk)); BUG_ON(clk_prepare_enable(data->aclk)); } static void __sysmmu_disable_clocks(struct sysmmu_drvdata *data) { clk_disable_unprepare(data->aclk); clk_disable_unprepare(data->pclk); clk_disable_unprepare(data->clk); clk_disable_unprepare(data->clk_master); } static void __sysmmu_get_version(struct sysmmu_drvdata *data) { u32 ver; __sysmmu_enable_clocks(data); ver = readl(data->sfrbase + REG_MMU_VERSION); /* controllers on some SoCs don't report proper version */ if (ver == 0x80000001u) data->version = MAKE_MMU_VER(1, 0); else data->version = MMU_RAW_VER(ver); dev_dbg(data->sysmmu, "hardware version: %d.%d\n", MMU_MAJ_VER(data->version), MMU_MIN_VER(data->version)); __sysmmu_disable_clocks(data); } static void show_fault_information(struct sysmmu_drvdata *data, const struct sysmmu_fault_info *finfo, sysmmu_iova_t fault_addr) { sysmmu_pte_t *ent; dev_err(data->sysmmu, "%s: %s FAULT occurred at %#x\n", dev_name(data->master), finfo->name, fault_addr); dev_dbg(data->sysmmu, "Page table base: %pa\n", &data->pgtable); ent = section_entry(phys_to_virt(data->pgtable), fault_addr); dev_dbg(data->sysmmu, "\tLv1 entry: %#x\n", *ent); if (lv1ent_page(ent)) { ent = page_entry(ent, fault_addr); dev_dbg(data->sysmmu, "\t Lv2 entry: %#x\n", *ent); } } static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id) { /* SYSMMU is in blocked state when interrupt occurred. */ struct sysmmu_drvdata *data = dev_id; const struct sysmmu_fault_info *finfo; unsigned int i, n, itype; sysmmu_iova_t fault_addr; unsigned short reg_status, reg_clear; int ret = -ENOSYS; WARN_ON(!data->active); if (MMU_MAJ_VER(data->version) < 5) { reg_status = REG_INT_STATUS; reg_clear = REG_INT_CLEAR; finfo = sysmmu_faults; n = ARRAY_SIZE(sysmmu_faults); } else { reg_status = REG_V5_INT_STATUS; reg_clear = REG_V5_INT_CLEAR; finfo = sysmmu_v5_faults; n = ARRAY_SIZE(sysmmu_v5_faults); } spin_lock(&data->lock); clk_enable(data->clk_master); itype = __ffs(readl(data->sfrbase + reg_status)); for (i = 0; i < n; i++, finfo++) if (finfo->bit == itype) break; /* unknown/unsupported fault */ BUG_ON(i == n); /* print debug message */ fault_addr = readl(data->sfrbase + finfo->addr_reg); show_fault_information(data, finfo, fault_addr); if (data->domain) ret = report_iommu_fault(&data->domain->domain, data->master, fault_addr, finfo->type); /* fault is not recovered by fault handler */ BUG_ON(ret != 0); writel(1 << itype, data->sfrbase + reg_clear); sysmmu_unblock(data); clk_disable(data->clk_master); spin_unlock(&data->lock); return IRQ_HANDLED; } static void __sysmmu_disable(struct sysmmu_drvdata *data) { unsigned long flags; clk_enable(data->clk_master); spin_lock_irqsave(&data->lock, flags); writel(CTRL_DISABLE, data->sfrbase + REG_MMU_CTRL); writel(0, data->sfrbase + REG_MMU_CFG); data->active = false; spin_unlock_irqrestore(&data->lock, flags); __sysmmu_disable_clocks(data); } static void __sysmmu_init_config(struct sysmmu_drvdata *data) { unsigned int cfg; if (data->version <= MAKE_MMU_VER(3, 1)) cfg = CFG_LRU | CFG_QOS(15); else if (data->version <= MAKE_MMU_VER(3, 2)) cfg = CFG_LRU | CFG_QOS(15) | CFG_FLPDCACHE | CFG_SYSSEL; else cfg = CFG_QOS(15) | CFG_FLPDCACHE | CFG_ACGEN; cfg |= CFG_EAP; /* enable access protection bits check */ writel(cfg, data->sfrbase + REG_MMU_CFG); } static void __sysmmu_enable(struct sysmmu_drvdata *data) { unsigned long flags; __sysmmu_enable_clocks(data); spin_lock_irqsave(&data->lock, flags); writel(CTRL_BLOCK, data->sfrbase + REG_MMU_CTRL); __sysmmu_init_config(data); __sysmmu_set_ptbase(data, data->pgtable); writel(CTRL_ENABLE, data->sfrbase + REG_MMU_CTRL); data->active = true; spin_unlock_irqrestore(&data->lock, flags); /* * SYSMMU driver keeps master's clock enabled only for the short * time, while accessing the registers. For performing address * translation during DMA transaction it relies on the client * driver to enable it. */ clk_disable(data->clk_master); } static void sysmmu_tlb_invalidate_flpdcache(struct sysmmu_drvdata *data, sysmmu_iova_t iova) { unsigned long flags; spin_lock_irqsave(&data->lock, flags); if (data->active && data->version >= MAKE_MMU_VER(3, 3)) { clk_enable(data->clk_master); if (sysmmu_block(data)) { if (data->version >= MAKE_MMU_VER(5, 0)) __sysmmu_tlb_invalidate(data); else __sysmmu_tlb_invalidate_entry(data, iova, 1); sysmmu_unblock(data); } clk_disable(data->clk_master); } spin_unlock_irqrestore(&data->lock, flags); } static void sysmmu_tlb_invalidate_entry(struct sysmmu_drvdata *data, sysmmu_iova_t iova, size_t size) { unsigned long flags; spin_lock_irqsave(&data->lock, flags); if (data->active) { unsigned int num_inv = 1; clk_enable(data->clk_master); /* * L2TLB invalidation required * 4KB page: 1 invalidation * 64KB page: 16 invalidations * 1MB page: 64 invalidations * because it is set-associative TLB * with 8-way and 64 sets. * 1MB page can be cached in one of all sets. * 64KB page can be one of 16 consecutive sets. */ if (MMU_MAJ_VER(data->version) == 2) num_inv = min_t(unsigned int, size / PAGE_SIZE, 64); if (sysmmu_block(data)) { __sysmmu_tlb_invalidate_entry(data, iova, num_inv); sysmmu_unblock(data); } clk_disable(data->clk_master); } spin_unlock_irqrestore(&data->lock, flags); } static const struct iommu_ops exynos_iommu_ops; static int exynos_sysmmu_probe(struct platform_device *pdev) { int irq, ret; struct device *dev = &pdev->dev; struct sysmmu_drvdata *data; struct resource *res; data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); if (!data) return -ENOMEM; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); data->sfrbase = devm_ioremap_resource(dev, res); if (IS_ERR(data->sfrbase)) return PTR_ERR(data->sfrbase); irq = platform_get_irq(pdev, 0); if (irq <= 0) return irq; ret = devm_request_irq(dev, irq, exynos_sysmmu_irq, 0, dev_name(dev), data); if (ret) { dev_err(dev, "Unabled to register handler of irq %d\n", irq); return ret; } data->clk = devm_clk_get(dev, "sysmmu"); if (PTR_ERR(data->clk) == -ENOENT) data->clk = NULL; else if (IS_ERR(data->clk)) return PTR_ERR(data->clk); data->aclk = devm_clk_get(dev, "aclk"); if (PTR_ERR(data->aclk) == -ENOENT) data->aclk = NULL; else if (IS_ERR(data->aclk)) return PTR_ERR(data->aclk); data->pclk = devm_clk_get(dev, "pclk"); if (PTR_ERR(data->pclk) == -ENOENT) data->pclk = NULL; else if (IS_ERR(data->pclk)) return PTR_ERR(data->pclk); if (!data->clk && (!data->aclk || !data->pclk)) { dev_err(dev, "Failed to get device clock(s)!\n"); return -ENOSYS; } data->clk_master = devm_clk_get(dev, "master"); if (PTR_ERR(data->clk_master) == -ENOENT) data->clk_master = NULL; else if (IS_ERR(data->clk_master)) return PTR_ERR(data->clk_master); data->sysmmu = dev; spin_lock_init(&data->lock); ret = iommu_device_sysfs_add(&data->iommu, &pdev->dev, NULL, dev_name(data->sysmmu)); if (ret) return ret; ret = iommu_device_register(&data->iommu, &exynos_iommu_ops, dev); if (ret) return ret; platform_set_drvdata(pdev, data); __sysmmu_get_version(data); if (PG_ENT_SHIFT < 0) { if (MMU_MAJ_VER(data->version) < 5) { PG_ENT_SHIFT = SYSMMU_PG_ENT_SHIFT; LV1_PROT = SYSMMU_LV1_PROT; LV2_PROT = SYSMMU_LV2_PROT; } else { PG_ENT_SHIFT = SYSMMU_V5_PG_ENT_SHIFT; LV1_PROT = SYSMMU_V5_LV1_PROT; LV2_PROT = SYSMMU_V5_LV2_PROT; } } /* * use the first registered sysmmu device for performing * dma mapping operations on iommu page tables (cpu cache flush) */ if (!dma_dev) dma_dev = &pdev->dev; pm_runtime_enable(dev); return 0; } static int __maybe_unused exynos_sysmmu_suspend(struct device *dev) { struct sysmmu_drvdata *data = dev_get_drvdata(dev); struct device *master = data->master; if (master) { struct exynos_iommu_owner *owner = dev_iommu_priv_get(master); mutex_lock(&owner->rpm_lock); if (data->domain) { dev_dbg(data->sysmmu, "saving state\n"); __sysmmu_disable(data); } mutex_unlock(&owner->rpm_lock); } return 0; } static int __maybe_unused exynos_sysmmu_resume(struct device *dev) { struct sysmmu_drvdata *data = dev_get_drvdata(dev); struct device *master = data->master; if (master) { struct exynos_iommu_owner *owner = dev_iommu_priv_get(master); mutex_lock(&owner->rpm_lock); if (data->domain) { dev_dbg(data->sysmmu, "restoring state\n"); __sysmmu_enable(data); } mutex_unlock(&owner->rpm_lock); } return 0; } static const struct dev_pm_ops sysmmu_pm_ops = { SET_RUNTIME_PM_OPS(exynos_sysmmu_suspend, exynos_sysmmu_resume, NULL) SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, pm_runtime_force_resume) }; static const struct of_device_id sysmmu_of_match[] = { { .compatible = "samsung,exynos-sysmmu", }, { }, }; static struct platform_driver exynos_sysmmu_driver __refdata = { .probe = exynos_sysmmu_probe, .driver = { .name = "exynos-sysmmu", .of_match_table = sysmmu_of_match, .pm = &sysmmu_pm_ops, .suppress_bind_attrs = true, } }; static inline void exynos_iommu_set_pte(sysmmu_pte_t *ent, sysmmu_pte_t val) { dma_sync_single_for_cpu(dma_dev, virt_to_phys(ent), sizeof(*ent), DMA_TO_DEVICE); *ent = cpu_to_le32(val); dma_sync_single_for_device(dma_dev, virt_to_phys(ent), sizeof(*ent), DMA_TO_DEVICE); } static struct iommu_domain *exynos_iommu_domain_alloc(unsigned type) { struct exynos_iommu_domain *domain; dma_addr_t handle; int i; /* Check if correct PTE offsets are initialized */ BUG_ON(PG_ENT_SHIFT < 0 || !dma_dev); if (type != IOMMU_DOMAIN_DMA && type != IOMMU_DOMAIN_UNMANAGED) return NULL; domain = kzalloc(sizeof(*domain), GFP_KERNEL); if (!domain) return NULL; domain->pgtable = (sysmmu_pte_t *)__get_free_pages(GFP_KERNEL, 2); if (!domain->pgtable) goto err_pgtable; domain->lv2entcnt = (short *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, 1); if (!domain->lv2entcnt) goto err_counter; /* Workaround for System MMU v3.3 to prevent caching 1MiB mapping */ for (i = 0; i < NUM_LV1ENTRIES; i++) domain->pgtable[i] = ZERO_LV2LINK; handle = dma_map_single(dma_dev, domain->pgtable, LV1TABLE_SIZE, DMA_TO_DEVICE); /* For mapping page table entries we rely on dma == phys */ BUG_ON(handle != virt_to_phys(domain->pgtable)); if (dma_mapping_error(dma_dev, handle)) goto err_lv2ent; spin_lock_init(&domain->lock); spin_lock_init(&domain->pgtablelock); INIT_LIST_HEAD(&domain->clients); domain->domain.geometry.aperture_start = 0; domain->domain.geometry.aperture_end = ~0UL; domain->domain.geometry.force_aperture = true; return &domain->domain; err_lv2ent: free_pages((unsigned long)domain->lv2entcnt, 1); err_counter: free_pages((unsigned long)domain->pgtable, 2); err_pgtable: kfree(domain); return NULL; } static void exynos_iommu_domain_free(struct iommu_domain *iommu_domain) { struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain); struct sysmmu_drvdata *data, *next; unsigned long flags; int i; WARN_ON(!list_empty(&domain->clients)); spin_lock_irqsave(&domain->lock, flags); list_for_each_entry_safe(data, next, &domain->clients, domain_node) { spin_lock(&data->lock); __sysmmu_disable(data); data->pgtable = 0; data->domain = NULL; list_del_init(&data->domain_node); spin_unlock(&data->lock); } spin_unlock_irqrestore(&domain->lock, flags); dma_unmap_single(dma_dev, virt_to_phys(domain->pgtable), LV1TABLE_SIZE, DMA_TO_DEVICE); for (i = 0; i < NUM_LV1ENTRIES; i++) if (lv1ent_page(domain->pgtable + i)) { phys_addr_t base = lv2table_base(domain->pgtable + i); dma_unmap_single(dma_dev, base, LV2TABLE_SIZE, DMA_TO_DEVICE); kmem_cache_free(lv2table_kmem_cache, phys_to_virt(base)); } free_pages((unsigned long)domain->pgtable, 2); free_pages((unsigned long)domain->lv2entcnt, 1); kfree(domain); } static void exynos_iommu_detach_device(struct iommu_domain *iommu_domain, struct device *dev) { struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain); struct exynos_iommu_owner *owner = dev_iommu_priv_get(dev); phys_addr_t pagetable = virt_to_phys(domain->pgtable); struct sysmmu_drvdata *data, *next; unsigned long flags; if (!has_sysmmu(dev) || owner->domain != iommu_domain) return; mutex_lock(&owner->rpm_lock); list_for_each_entry(data, &owner->controllers, owner_node) { pm_runtime_get_noresume(data->sysmmu); if (pm_runtime_active(data->sysmmu)) __sysmmu_disable(data); pm_runtime_put(data->sysmmu); } spin_lock_irqsave(&domain->lock, flags); list_for_each_entry_safe(data, next, &domain->clients, domain_node) { spin_lock(&data->lock); data->pgtable = 0; data->domain = NULL; list_del_init(&data->domain_node); spin_unlock(&data->lock); } owner->domain = NULL; spin_unlock_irqrestore(&domain->lock, flags); mutex_unlock(&owner->rpm_lock); dev_dbg(dev, "%s: Detached IOMMU with pgtable %pa\n", __func__, &pagetable); } static int exynos_iommu_attach_device(struct iommu_domain *iommu_domain, struct device *dev) { struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain); struct exynos_iommu_owner *owner = dev_iommu_priv_get(dev); struct sysmmu_drvdata *data; phys_addr_t pagetable = virt_to_phys(domain->pgtable); unsigned long flags; if (!has_sysmmu(dev)) return -ENODEV; if (owner->domain) exynos_iommu_detach_device(owner->domain, dev); mutex_lock(&owner->rpm_lock); spin_lock_irqsave(&domain->lock, flags); list_for_each_entry(data, &owner->controllers, owner_node) { spin_lock(&data->lock); data->pgtable = pagetable; data->domain = domain; list_add_tail(&data->domain_node, &domain->clients); spin_unlock(&data->lock); } owner->domain = iommu_domain; spin_unlock_irqrestore(&domain->lock, flags); list_for_each_entry(data, &owner->controllers, owner_node) { pm_runtime_get_noresume(data->sysmmu); if (pm_runtime_active(data->sysmmu)) __sysmmu_enable(data); pm_runtime_put(data->sysmmu); } mutex_unlock(&owner->rpm_lock); dev_dbg(dev, "%s: Attached IOMMU with pgtable %pa\n", __func__, &pagetable); return 0; } static sysmmu_pte_t *alloc_lv2entry(struct exynos_iommu_domain *domain, sysmmu_pte_t *sent, sysmmu_iova_t iova, short *pgcounter) { if (lv1ent_section(sent)) { WARN(1, "Trying mapping on %#08x mapped with 1MiB page", iova); return ERR_PTR(-EADDRINUSE); } if (lv1ent_fault(sent)) { dma_addr_t handle; sysmmu_pte_t *pent; bool need_flush_flpd_cache = lv1ent_zero(sent); pent = kmem_cache_zalloc(lv2table_kmem_cache, GFP_ATOMIC); BUG_ON((uintptr_t)pent & (LV2TABLE_SIZE - 1)); if (!pent) return ERR_PTR(-ENOMEM); exynos_iommu_set_pte(sent, mk_lv1ent_page(virt_to_phys(pent))); kmemleak_ignore(pent); *pgcounter = NUM_LV2ENTRIES; handle = dma_map_single(dma_dev, pent, LV2TABLE_SIZE, DMA_TO_DEVICE); if (dma_mapping_error(dma_dev, handle)) { kmem_cache_free(lv2table_kmem_cache, pent); return ERR_PTR(-EADDRINUSE); } /* * If pre-fetched SLPD is a faulty SLPD in zero_l2_table, * FLPD cache may cache the address of zero_l2_table. This * function replaces the zero_l2_table with new L2 page table * to write valid mappings. * Accessing the valid area may cause page fault since FLPD * cache may still cache zero_l2_table for the valid area * instead of new L2 page table that has the mapping * information of the valid area. * Thus any replacement of zero_l2_table with other valid L2 * page table must involve FLPD cache invalidation for System * MMU v3.3. * FLPD cache invalidation is performed with TLB invalidation * by VPN without blocking. It is safe to invalidate TLB without * blocking because the target address of TLB invalidation is * not currently mapped. */ if (need_flush_flpd_cache) { struct sysmmu_drvdata *data; spin_lock(&domain->lock); list_for_each_entry(data, &domain->clients, domain_node) sysmmu_tlb_invalidate_flpdcache(data, iova); spin_unlock(&domain->lock); } } return page_entry(sent, iova); } static int lv1set_section(struct exynos_iommu_domain *domain, sysmmu_pte_t *sent, sysmmu_iova_t iova, phys_addr_t paddr, int prot, short *pgcnt) { if (lv1ent_section(sent)) { WARN(1, "Trying mapping on 1MiB@%#08x that is mapped", iova); return -EADDRINUSE; } if (lv1ent_page(sent)) { if (*pgcnt != NUM_LV2ENTRIES) { WARN(1, "Trying mapping on 1MiB@%#08x that is mapped", iova); return -EADDRINUSE; } kmem_cache_free(lv2table_kmem_cache, page_entry(sent, 0)); *pgcnt = 0; } exynos_iommu_set_pte(sent, mk_lv1ent_sect(paddr, prot)); spin_lock(&domain->lock); if (lv1ent_page_zero(sent)) { struct sysmmu_drvdata *data; /* * Flushing FLPD cache in System MMU v3.3 that may cache a FLPD * entry by speculative prefetch of SLPD which has no mapping. */ list_for_each_entry(data, &domain->clients, domain_node) sysmmu_tlb_invalidate_flpdcache(data, iova); } spin_unlock(&domain->lock); return 0; } static int lv2set_page(sysmmu_pte_t *pent, phys_addr_t paddr, size_t size, int prot, short *pgcnt) { if (size == SPAGE_SIZE) { if (WARN_ON(!lv2ent_fault(pent))) return -EADDRINUSE; exynos_iommu_set_pte(pent, mk_lv2ent_spage(paddr, prot)); *pgcnt -= 1; } else { /* size == LPAGE_SIZE */ int i; dma_addr_t pent_base = virt_to_phys(pent); dma_sync_single_for_cpu(dma_dev, pent_base, sizeof(*pent) * SPAGES_PER_LPAGE, DMA_TO_DEVICE); for (i = 0; i < SPAGES_PER_LPAGE; i++, pent++) { if (WARN_ON(!lv2ent_fault(pent))) { if (i > 0) memset(pent - i, 0, sizeof(*pent) * i); return -EADDRINUSE; } *pent = mk_lv2ent_lpage(paddr, prot); } dma_sync_single_for_device(dma_dev, pent_base, sizeof(*pent) * SPAGES_PER_LPAGE, DMA_TO_DEVICE); *pgcnt -= SPAGES_PER_LPAGE; } return 0; } /* * *CAUTION* to the I/O virtual memory managers that support exynos-iommu: * * System MMU v3.x has advanced logic to improve address translation * performance with caching more page table entries by a page table walk. * However, the logic has a bug that while caching faulty page table entries, * System MMU reports page fault if the cached fault entry is hit even though * the fault entry is updated to a valid entry after the entry is cached. * To prevent caching faulty page table entries which may be updated to valid * entries later, the virtual memory manager should care about the workaround * for the problem. The following describes the workaround. * * Any two consecutive I/O virtual address regions must have a hole of 128KiB * at maximum to prevent misbehavior of System MMU 3.x (workaround for h/w bug). * * Precisely, any start address of I/O virtual region must be aligned with * the following sizes for System MMU v3.1 and v3.2. * System MMU v3.1: 128KiB * System MMU v3.2: 256KiB * * Because System MMU v3.3 caches page table entries more aggressively, it needs * more workarounds. * - Any two consecutive I/O virtual regions must have a hole of size larger * than or equal to 128KiB. * - Start address of an I/O virtual region must be aligned by 128KiB. */ static int exynos_iommu_map(struct iommu_domain *iommu_domain, unsigned long l_iova, phys_addr_t paddr, size_t size, int prot, gfp_t gfp) { struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain); sysmmu_pte_t *entry; sysmmu_iova_t iova = (sysmmu_iova_t)l_iova; unsigned long flags; int ret = -ENOMEM; BUG_ON(domain->pgtable == NULL); prot &= SYSMMU_SUPPORTED_PROT_BITS; spin_lock_irqsave(&domain->pgtablelock, flags); entry = section_entry(domain->pgtable, iova); if (size == SECT_SIZE) { ret = lv1set_section(domain, entry, iova, paddr, prot, &domain->lv2entcnt[lv1ent_offset(iova)]); } else { sysmmu_pte_t *pent; pent = alloc_lv2entry(domain, entry, iova, &domain->lv2entcnt[lv1ent_offset(iova)]); if (IS_ERR(pent)) ret = PTR_ERR(pent); else ret = lv2set_page(pent, paddr, size, prot, &domain->lv2entcnt[lv1ent_offset(iova)]); } if (ret) pr_err("%s: Failed(%d) to map %#zx bytes @ %#x\n", __func__, ret, size, iova); spin_unlock_irqrestore(&domain->pgtablelock, flags); return ret; } static void exynos_iommu_tlb_invalidate_entry(struct exynos_iommu_domain *domain, sysmmu_iova_t iova, size_t size) { struct sysmmu_drvdata *data; unsigned long flags; spin_lock_irqsave(&domain->lock, flags); list_for_each_entry(data, &domain->clients, domain_node) sysmmu_tlb_invalidate_entry(data, iova, size); spin_unlock_irqrestore(&domain->lock, flags); } static size_t exynos_iommu_unmap(struct iommu_domain *iommu_domain, unsigned long l_iova, size_t size, struct iommu_iotlb_gather *gather) { struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain); sysmmu_iova_t iova = (sysmmu_iova_t)l_iova; sysmmu_pte_t *ent; size_t err_pgsize; unsigned long flags; BUG_ON(domain->pgtable == NULL); spin_lock_irqsave(&domain->pgtablelock, flags); ent = section_entry(domain->pgtable, iova); if (lv1ent_section(ent)) { if (WARN_ON(size < SECT_SIZE)) { err_pgsize = SECT_SIZE; goto err; } /* workaround for h/w bug in System MMU v3.3 */ exynos_iommu_set_pte(ent, ZERO_LV2LINK); size = SECT_SIZE; goto done; } if (unlikely(lv1ent_fault(ent))) { if (size > SECT_SIZE) size = SECT_SIZE; goto done; } /* lv1ent_page(sent) == true here */ ent = page_entry(ent, iova); if (unlikely(lv2ent_fault(ent))) { size = SPAGE_SIZE; goto done; } if (lv2ent_small(ent)) { exynos_iommu_set_pte(ent, 0); size = SPAGE_SIZE; domain->lv2entcnt[lv1ent_offset(iova)] += 1; goto done; } /* lv1ent_large(ent) == true here */ if (WARN_ON(size < LPAGE_SIZE)) { err_pgsize = LPAGE_SIZE; goto err; } dma_sync_single_for_cpu(dma_dev, virt_to_phys(ent), sizeof(*ent) * SPAGES_PER_LPAGE, DMA_TO_DEVICE); memset(ent, 0, sizeof(*ent) * SPAGES_PER_LPAGE); dma_sync_single_for_device(dma_dev, virt_to_phys(ent), sizeof(*ent) * SPAGES_PER_LPAGE, DMA_TO_DEVICE); size = LPAGE_SIZE; domain->lv2entcnt[lv1ent_offset(iova)] += SPAGES_PER_LPAGE; done: spin_unlock_irqrestore(&domain->pgtablelock, flags); exynos_iommu_tlb_invalidate_entry(domain, iova, size); return size; err: spin_unlock_irqrestore(&domain->pgtablelock, flags); pr_err("%s: Failed: size(%#zx) @ %#x is smaller than page size %#zx\n", __func__, size, iova, err_pgsize); return 0; } static phys_addr_t exynos_iommu_iova_to_phys(struct iommu_domain *iommu_domain, dma_addr_t iova) { struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain); sysmmu_pte_t *entry; unsigned long flags; phys_addr_t phys = 0; spin_lock_irqsave(&domain->pgtablelock, flags); entry = section_entry(domain->pgtable, iova); if (lv1ent_section(entry)) { phys = section_phys(entry) + section_offs(iova); } else if (lv1ent_page(entry)) { entry = page_entry(entry, iova); if (lv2ent_large(entry)) phys = lpage_phys(entry) + lpage_offs(iova); else if (lv2ent_small(entry)) phys = spage_phys(entry) + spage_offs(iova); } spin_unlock_irqrestore(&domain->pgtablelock, flags); return phys; } static struct iommu_device *exynos_iommu_probe_device(struct device *dev) { struct exynos_iommu_owner *owner = dev_iommu_priv_get(dev); struct sysmmu_drvdata *data; if (!has_sysmmu(dev)) return ERR_PTR(-ENODEV); list_for_each_entry(data, &owner->controllers, owner_node) { /* * SYSMMU will be runtime activated via device link * (dependency) to its master device, so there are no * direct calls to pm_runtime_get/put in this driver. */ data->link = device_link_add(dev, data->sysmmu, DL_FLAG_STATELESS | DL_FLAG_PM_RUNTIME); } /* There is always at least one entry, see exynos_iommu_of_xlate() */ data = list_first_entry(&owner->controllers, struct sysmmu_drvdata, owner_node); return &data->iommu; } static void exynos_iommu_release_device(struct device *dev) { struct exynos_iommu_owner *owner = dev_iommu_priv_get(dev); struct sysmmu_drvdata *data; if (owner->domain) { struct iommu_group *group = iommu_group_get(dev); if (group) { WARN_ON(owner->domain != iommu_group_default_domain(group)); exynos_iommu_detach_device(owner->domain, dev); iommu_group_put(group); } } list_for_each_entry(data, &owner->controllers, owner_node) device_link_del(data->link); } static int exynos_iommu_of_xlate(struct device *dev, struct of_phandle_args *spec) { struct platform_device *sysmmu = of_find_device_by_node(spec->np); struct exynos_iommu_owner *owner = dev_iommu_priv_get(dev); struct sysmmu_drvdata *data, *entry; if (!sysmmu) return -ENODEV; data = platform_get_drvdata(sysmmu); if (!data) { put_device(&sysmmu->dev); return -ENODEV; } if (!owner) { owner = kzalloc(sizeof(*owner), GFP_KERNEL); if (!owner) { put_device(&sysmmu->dev); return -ENOMEM; } INIT_LIST_HEAD(&owner->controllers); mutex_init(&owner->rpm_lock); dev_iommu_priv_set(dev, owner); } list_for_each_entry(entry, &owner->controllers, owner_node) if (entry == data) return 0; list_add_tail(&data->owner_node, &owner->controllers); data->master = dev; return 0; } static const struct iommu_ops exynos_iommu_ops = { .domain_alloc = exynos_iommu_domain_alloc, .device_group = generic_device_group, .probe_device = exynos_iommu_probe_device, .release_device = exynos_iommu_release_device, .pgsize_bitmap = SECT_SIZE | LPAGE_SIZE | SPAGE_SIZE, .of_xlate = exynos_iommu_of_xlate, .default_domain_ops = &(const struct iommu_domain_ops) { .attach_dev = exynos_iommu_attach_device, .detach_dev = exynos_iommu_detach_device, .map = exynos_iommu_map, .unmap = exynos_iommu_unmap, .iova_to_phys = exynos_iommu_iova_to_phys, .free = exynos_iommu_domain_free, } }; static int __init exynos_iommu_init(void) { struct device_node *np; int ret; np = of_find_matching_node(NULL, sysmmu_of_match); if (!np) return 0; of_node_put(np); lv2table_kmem_cache = kmem_cache_create("exynos-iommu-lv2table", LV2TABLE_SIZE, LV2TABLE_SIZE, 0, NULL); if (!lv2table_kmem_cache) { pr_err("%s: Failed to create kmem cache\n", __func__); return -ENOMEM; } ret = platform_driver_register(&exynos_sysmmu_driver); if (ret) { pr_err("%s: Failed to register driver\n", __func__); goto err_reg_driver; } zero_lv2_table = kmem_cache_zalloc(lv2table_kmem_cache, GFP_KERNEL); if (zero_lv2_table == NULL) { pr_err("%s: Failed to allocate zero level2 page table\n", __func__); ret = -ENOMEM; goto err_zero_lv2; } ret = bus_set_iommu(&platform_bus_type, &exynos_iommu_ops); if (ret) { pr_err("%s: Failed to register exynos-iommu driver.\n", __func__); goto err_set_iommu; } return 0; err_set_iommu: kmem_cache_free(lv2table_kmem_cache, zero_lv2_table); err_zero_lv2: platform_driver_unregister(&exynos_sysmmu_driver); err_reg_driver: kmem_cache_destroy(lv2table_kmem_cache); return ret; } core_initcall(exynos_iommu_init);