--- /dev/null
+/* linux/drivers/iommu/exynos_iommu.c
+ *
+ * Copyright (c) 2011 Samsung Electronics Co., Ltd.
+ * http://www.samsung.com
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifdef CONFIG_EXYNOS_IOMMU_DEBUG
+#define DEBUG
+#endif
+
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/pm_runtime.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/mm.h>
+#include <linux/iommu.h>
+#include <linux/errno.h>
+#include <linux/list.h>
+#include <linux/memblock.h>
+#include <linux/export.h>
+
+#include <asm/cacheflush.h>
+#include <asm/pgtable.h>
+
+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)
+
+static u32 sysmmu_page_offset(sysmmu_iova_t iova, u32 size)
+{
+ return iova & (size - 1);
+}
+
+#define section_phys(sent) (*(sent) & SECT_MASK)
+#define section_offs(iova) sysmmu_page_offset((iova), SECT_SIZE)
+#define lpage_phys(pent) (*(pent) & LPAGE_MASK)
+#define lpage_offs(iova) sysmmu_page_offset((iova), LPAGE_SIZE)
+#define spage_phys(pent) (*(pent) & SPAGE_MASK)
+#define spage_offs(iova) sysmmu_page_offset((iova), SPAGE_SIZE)
+
+#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 LV2TABLE_SIZE (NUM_LV2ENTRIES * sizeof(sysmmu_pte_t))
+
+#define SPAGES_PER_LPAGE (LPAGE_SIZE / SPAGE_SIZE)
+
+#define lv2table_base(sent) (*(sent) & 0xFFFFFC00)
+
+#define mk_lv1ent_sect(pa) ((pa) | 2)
+#define mk_lv1ent_page(pa) ((pa) | 1)
+#define mk_lv2ent_lpage(pa) ((pa) | 1)
+#define mk_lv2ent_spage(pa) ((pa) | 2)
+
+#define CTRL_ENABLE 0x5
+#define CTRL_BLOCK 0x7
+#define CTRL_DISABLE 0x0
+
+#define CFG_LRU 0x1
+#define CFG_QOS(n) ((n & 0xF) << 7)
+#define CFG_MASK 0x0150FFFF /* Selecting bit 0-15, 20, 22 and 24 */
+#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 */
+
+#define REG_MMU_CTRL 0x000
+#define REG_MMU_CFG 0x004
+#define REG_MMU_STATUS 0x008
+#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
+
+#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))
+
+#define REG_PB0_SADDR 0x04C
+#define REG_PB0_EADDR 0x050
+#define REG_PB1_SADDR 0x054
+#define REG_PB1_EADDR 0x058
+
+#define has_sysmmu(dev) (dev->archdata.iommu != NULL)
+
+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);
+}
+
+enum exynos_sysmmu_inttype {
+ SYSMMU_PAGEFAULT,
+ SYSMMU_AR_MULTIHIT,
+ SYSMMU_AW_MULTIHIT,
+ SYSMMU_BUSERROR,
+ SYSMMU_AR_SECURITY,
+ SYSMMU_AR_ACCESS,
+ SYSMMU_AW_SECURITY,
+ SYSMMU_AW_PROTECTION, /* 7 */
+ SYSMMU_FAULT_UNKNOWN,
+ SYSMMU_FAULTS_NUM
+};
+
+static unsigned short fault_reg_offset[SYSMMU_FAULTS_NUM] = {
+ REG_PAGE_FAULT_ADDR,
+ REG_AR_FAULT_ADDR,
+ REG_AW_FAULT_ADDR,
+ REG_DEFAULT_SLAVE_ADDR,
+ REG_AR_FAULT_ADDR,
+ REG_AR_FAULT_ADDR,
+ REG_AW_FAULT_ADDR,
+ REG_AW_FAULT_ADDR
+};
+
+static char *sysmmu_fault_name[SYSMMU_FAULTS_NUM] = {
+ "PAGE FAULT",
+ "AR MULTI-HIT FAULT",
+ "AW MULTI-HIT FAULT",
+ "BUS ERROR",
+ "AR SECURITY PROTECTION FAULT",
+ "AR ACCESS PROTECTION FAULT",
+ "AW SECURITY PROTECTION FAULT",
+ "AW ACCESS PROTECTION FAULT",
+ "UNKNOWN FAULT"
+};
+
+/* attached to dev.archdata.iommu of the master device */
+struct exynos_iommu_owner {
+ struct list_head client; /* entry of exynos_iommu_domain.clients */
+ struct device *dev;
+ struct device *sysmmu;
+ struct iommu_domain *domain;
+ void *vmm_data; /* IO virtual memory manager's data */
+ spinlock_t lock; /* Lock to preserve consistency of System MMU */
+};
+
+struct exynos_iommu_domain {
+ struct list_head clients; /* list of sysmmu_drvdata.node */
+ sysmmu_pte_t *pgtable; /* lv1 page table, 16KB */
+ short *lv2entcnt; /* free lv2 entry counter for each section */
+ spinlock_t lock; /* lock for this structure */
+ spinlock_t pgtablelock; /* lock for modifying page table @ pgtable */
+ struct iommu_domain domain; /* generic domain data structure */
+};
+
+struct sysmmu_drvdata {
+ struct device *sysmmu; /* System MMU's device descriptor */
+ struct device *master; /* Owner of system MMU */
+ void __iomem *sfrbase;
+ struct clk *clk;
+ struct clk *clk_master;
+ int activations;
+ spinlock_t lock;
+ struct iommu_domain *domain;
+ phys_addr_t pgtable;
+};
+
+static struct exynos_iommu_domain *to_exynos_domain(struct iommu_domain *dom)
+{
+ return container_of(dom, struct exynos_iommu_domain, domain);
+}
+
+static bool set_sysmmu_active(struct sysmmu_drvdata *data)
+{
+ /* return true if the System MMU was not active previously
+ and it needs to be initialized */
+ return ++data->activations == 1;
+}
+
+static bool set_sysmmu_inactive(struct sysmmu_drvdata *data)
+{
+ /* return true if the System MMU is needed to be disabled */
+ BUG_ON(data->activations < 1);
+ return --data->activations == 0;
+}
+
+static bool is_sysmmu_active(struct sysmmu_drvdata *data)
+{
+ return data->activations > 0;
+}
+
+static void sysmmu_unblock(void __iomem *sfrbase)
+{
+ __raw_writel(CTRL_ENABLE, sfrbase + REG_MMU_CTRL);
+}
+
+static unsigned int __raw_sysmmu_version(struct sysmmu_drvdata *data)
+{
+ return MMU_RAW_VER(__raw_readl(data->sfrbase + REG_MMU_VERSION));
+}
+
+static bool sysmmu_block(void __iomem *sfrbase)
+{
+ int i = 120;
+
+ __raw_writel(CTRL_BLOCK, sfrbase + REG_MMU_CTRL);
+ while ((i > 0) && !(__raw_readl(sfrbase + REG_MMU_STATUS) & 1))
+ --i;
+
+ if (!(__raw_readl(sfrbase + REG_MMU_STATUS) & 1)) {
+ sysmmu_unblock(sfrbase);
+ return false;
+ }
+
+ return true;
+}
+
+static void __sysmmu_tlb_invalidate(void __iomem *sfrbase)
+{
+ __raw_writel(0x1, sfrbase + REG_MMU_FLUSH);
+}
+
+static void __sysmmu_tlb_invalidate_entry(void __iomem *sfrbase,
+ sysmmu_iova_t iova, unsigned int num_inv)
+{
+ unsigned int i;
+
+ for (i = 0; i < num_inv; i++) {
+ __raw_writel((iova & SPAGE_MASK) | 1,
+ sfrbase + REG_MMU_FLUSH_ENTRY);
+ iova += SPAGE_SIZE;
+ }
+}
+
+static void __sysmmu_set_ptbase(void __iomem *sfrbase,
+ phys_addr_t pgd)
+{
+ __raw_writel(pgd, sfrbase + REG_PT_BASE_ADDR);
+
+ __sysmmu_tlb_invalidate(sfrbase);
+}
+
+static void show_fault_information(const char *name,
+ enum exynos_sysmmu_inttype itype,
+ phys_addr_t pgtable_base, sysmmu_iova_t fault_addr)
+{
+ sysmmu_pte_t *ent;
+
+ if ((itype >= SYSMMU_FAULTS_NUM) || (itype < SYSMMU_PAGEFAULT))
+ itype = SYSMMU_FAULT_UNKNOWN;
+
+ pr_err("%s occurred at %#x by %s(Page table base: %pa)\n",
+ sysmmu_fault_name[itype], fault_addr, name, &pgtable_base);
+
+ ent = section_entry(phys_to_virt(pgtable_base), fault_addr);
+ pr_err("\tLv1 entry: %#x\n", *ent);
+
+ if (lv1ent_page(ent)) {
+ ent = page_entry(ent, fault_addr);
+ pr_err("\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;
+ enum exynos_sysmmu_inttype itype;
+ sysmmu_iova_t addr = -1;
+ int ret = -ENOSYS;
+
+ WARN_ON(!is_sysmmu_active(data));
+
+ spin_lock(&data->lock);
+
+ if (!IS_ERR(data->clk_master))
+ clk_enable(data->clk_master);
+
+ itype = (enum exynos_sysmmu_inttype)
+ __ffs(__raw_readl(data->sfrbase + REG_INT_STATUS));
+ if (WARN_ON(!((itype >= 0) && (itype < SYSMMU_FAULT_UNKNOWN))))
+ itype = SYSMMU_FAULT_UNKNOWN;
+ else
+ addr = __raw_readl(data->sfrbase + fault_reg_offset[itype]);
+
+ if (itype == SYSMMU_FAULT_UNKNOWN) {
+ pr_err("%s: Fault is not occurred by System MMU '%s'!\n",
+ __func__, dev_name(data->sysmmu));
+ pr_err("%s: Please check if IRQ is correctly configured.\n",
+ __func__);
+ BUG();
+ } else {
+ unsigned int base =
+ __raw_readl(data->sfrbase + REG_PT_BASE_ADDR);
+ show_fault_information(dev_name(data->sysmmu),
+ itype, base, addr);
+ if (data->domain)
+ ret = report_iommu_fault(data->domain,
+ data->master, addr, itype);
+ }
+
+ /* fault is not recovered by fault handler */
+ BUG_ON(ret != 0);
+
+ __raw_writel(1 << itype, data->sfrbase + REG_INT_CLEAR);
+
+ sysmmu_unblock(data->sfrbase);
+
+ if (!IS_ERR(data->clk_master))
+ clk_disable(data->clk_master);
+
+ spin_unlock(&data->lock);
+
+ return IRQ_HANDLED;
+}
+
+static void __sysmmu_disable_nocount(struct sysmmu_drvdata *data)
+{
+ if (!IS_ERR(data->clk_master))
+ clk_enable(data->clk_master);
+
+ __raw_writel(CTRL_DISABLE, data->sfrbase + REG_MMU_CTRL);
+ __raw_writel(0, data->sfrbase + REG_MMU_CFG);
+
+ clk_disable(data->clk);
+ if (!IS_ERR(data->clk_master))
+ clk_disable(data->clk_master);
+}
+
+static bool __sysmmu_disable(struct sysmmu_drvdata *data)
+{
+ bool disabled;
+ unsigned long flags;
+
+ spin_lock_irqsave(&data->lock, flags);
+
+ disabled = set_sysmmu_inactive(data);
+
+ if (disabled) {
+ data->pgtable = 0;
+ data->domain = NULL;
+
+ __sysmmu_disable_nocount(data);
+
+ dev_dbg(data->sysmmu, "Disabled\n");
+ } else {
+ dev_dbg(data->sysmmu, "%d times left to disable\n",
+ data->activations);
+ }
+
+ spin_unlock_irqrestore(&data->lock, flags);
+
+ return disabled;
+}
+
+static void __sysmmu_init_config(struct sysmmu_drvdata *data)
+{
+ unsigned int cfg = CFG_LRU | CFG_QOS(15);
+ unsigned int ver;
+
+ ver = __raw_sysmmu_version(data);
+ if (MMU_MAJ_VER(ver) == 3) {
+ if (MMU_MIN_VER(ver) >= 2) {
+ cfg |= CFG_FLPDCACHE;
+ if (MMU_MIN_VER(ver) == 3) {
+ cfg |= CFG_ACGEN;
+ cfg &= ~CFG_LRU;
+ } else {
+ cfg |= CFG_SYSSEL;
+ }
+ }
+ }
+
+ __raw_writel(cfg, data->sfrbase + REG_MMU_CFG);
+}
+
+static void __sysmmu_enable_nocount(struct sysmmu_drvdata *data)
+{
+ if (!IS_ERR(data->clk_master))
+ clk_enable(data->clk_master);
+ clk_enable(data->clk);
+
+ __raw_writel(CTRL_BLOCK, data->sfrbase + REG_MMU_CTRL);
+
+ __sysmmu_init_config(data);
+
+ __sysmmu_set_ptbase(data->sfrbase, data->pgtable);
+
+ __raw_writel(CTRL_ENABLE, data->sfrbase + REG_MMU_CTRL);
+
+ if (!IS_ERR(data->clk_master))
+ clk_disable(data->clk_master);
+}
+
+static int __sysmmu_enable(struct sysmmu_drvdata *data,
+ phys_addr_t pgtable, struct iommu_domain *domain)
+{
+ int ret = 0;
+ unsigned long flags;
+
+ spin_lock_irqsave(&data->lock, flags);
+ if (set_sysmmu_active(data)) {
+ data->pgtable = pgtable;
+ data->domain = domain;
+
+ __sysmmu_enable_nocount(data);
+
+ dev_dbg(data->sysmmu, "Enabled\n");
+ } else {
+ ret = (pgtable == data->pgtable) ? 1 : -EBUSY;
+
+ dev_dbg(data->sysmmu, "already enabled\n");
+ }
+
+ if (WARN_ON(ret < 0))
+ set_sysmmu_inactive(data); /* decrement count */
+
+ spin_unlock_irqrestore(&data->lock, flags);
+
+ return ret;
+}
+
+/* __exynos_sysmmu_enable: Enables System MMU
+ *
+ * returns -error if an error occurred and System MMU is not enabled,
+ * 0 if the System MMU has been just enabled and 1 if System MMU was already
+ * enabled before.
+ */
+static int __exynos_sysmmu_enable(struct device *dev, phys_addr_t pgtable,
+ struct iommu_domain *domain)
+{
+ int ret = 0;
+ unsigned long flags;
+ struct exynos_iommu_owner *owner = dev->archdata.iommu;
+ struct sysmmu_drvdata *data;
+
+ BUG_ON(!has_sysmmu(dev));
+
+ spin_lock_irqsave(&owner->lock, flags);
+
+ data = dev_get_drvdata(owner->sysmmu);
+
+ ret = __sysmmu_enable(data, pgtable, domain);
+ if (ret >= 0)
+ data->master = dev;
+
+ spin_unlock_irqrestore(&owner->lock, flags);
+
+ return ret;
+}
+
+int exynos_sysmmu_enable(struct device *dev, phys_addr_t pgtable)
+{
+ BUG_ON(!memblock_is_memory(pgtable));
+
+ return __exynos_sysmmu_enable(dev, pgtable, NULL);
+}
+
+static bool exynos_sysmmu_disable(struct device *dev)
+{
+ unsigned long flags;
+ bool disabled = true;
+ struct exynos_iommu_owner *owner = dev->archdata.iommu;
+ struct sysmmu_drvdata *data;
+
+ BUG_ON(!has_sysmmu(dev));
+
+ spin_lock_irqsave(&owner->lock, flags);
+
+ data = dev_get_drvdata(owner->sysmmu);
+
+ disabled = __sysmmu_disable(data);
+ if (disabled)
+ data->master = NULL;
+
+ spin_unlock_irqrestore(&owner->lock, flags);
+
+ return disabled;
+}
+
+static void __sysmmu_tlb_invalidate_flpdcache(struct sysmmu_drvdata *data,
+ sysmmu_iova_t iova)
+{
+ if (__raw_sysmmu_version(data) == MAKE_MMU_VER(3, 3))
+ __raw_writel(iova | 0x1, data->sfrbase + REG_MMU_FLUSH_ENTRY);
+}
+
+static void sysmmu_tlb_invalidate_flpdcache(struct device *dev,
+ sysmmu_iova_t iova)
+{
+ unsigned long flags;
+ struct exynos_iommu_owner *owner = dev->archdata.iommu;
+ struct sysmmu_drvdata *data = dev_get_drvdata(owner->sysmmu);
+
+ if (!IS_ERR(data->clk_master))
+ clk_enable(data->clk_master);
+
+ spin_lock_irqsave(&data->lock, flags);
+ if (is_sysmmu_active(data))
+ __sysmmu_tlb_invalidate_flpdcache(data, iova);
+ spin_unlock_irqrestore(&data->lock, flags);
+
+ if (!IS_ERR(data->clk_master))
+ clk_disable(data->clk_master);
+}
+
+static void sysmmu_tlb_invalidate_entry(struct device *dev, sysmmu_iova_t iova,
+ size_t size)
+{
+ struct exynos_iommu_owner *owner = dev->archdata.iommu;
+ unsigned long flags;
+ struct sysmmu_drvdata *data;
+
+ data = dev_get_drvdata(owner->sysmmu);
+
+ spin_lock_irqsave(&data->lock, flags);
+ if (is_sysmmu_active(data)) {
+ unsigned int num_inv = 1;
+
+ if (!IS_ERR(data->clk_master))
+ 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(__raw_sysmmu_version(data)) == 2)
+ num_inv = min_t(unsigned int, size / PAGE_SIZE, 64);
+
+ if (sysmmu_block(data->sfrbase)) {
+ __sysmmu_tlb_invalidate_entry(
+ data->sfrbase, iova, num_inv);
+ sysmmu_unblock(data->sfrbase);
+ }
+ if (!IS_ERR(data->clk_master))
+ clk_disable(data->clk_master);
+ } else {
+ dev_dbg(dev, "disabled. Skipping TLB invalidation @ %#x\n",
+ iova);
+ }
+ spin_unlock_irqrestore(&data->lock, flags);
+}
+
+void exynos_sysmmu_tlb_invalidate(struct device *dev)
+{
+ struct exynos_iommu_owner *owner = dev->archdata.iommu;
+ unsigned long flags;
+ struct sysmmu_drvdata *data;
+
+ data = dev_get_drvdata(owner->sysmmu);
+
+ spin_lock_irqsave(&data->lock, flags);
+ if (is_sysmmu_active(data)) {
+ if (!IS_ERR(data->clk_master))
+ clk_enable(data->clk_master);
+ if (sysmmu_block(data->sfrbase)) {
+ __sysmmu_tlb_invalidate(data->sfrbase);
+ sysmmu_unblock(data->sfrbase);
+ }
+ if (!IS_ERR(data->clk_master))
+ clk_disable(data->clk_master);
+ } else {
+ dev_dbg(dev, "disabled. Skipping TLB invalidation\n");
+ }
+ spin_unlock_irqrestore(&data->lock, flags);
+}
+
+static int __init 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) {
+ dev_err(dev, "Unable to find IRQ resource\n");
+ 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 (IS_ERR(data->clk)) {
+ dev_err(dev, "Failed to get clock!\n");
+ return PTR_ERR(data->clk);
+ } else {
+ ret = clk_prepare(data->clk);
+ if (ret) {
+ dev_err(dev, "Failed to prepare clk\n");
+ return ret;
+ }
+ }
+
+ data->clk_master = devm_clk_get(dev, "master");
+ if (!IS_ERR(data->clk_master)) {
+ ret = clk_prepare(data->clk_master);
+ if (ret) {
+ clk_unprepare(data->clk);
+ dev_err(dev, "Failed to prepare master's clk\n");
+ return ret;
+ }
+ }
+
+ data->sysmmu = dev;
+ spin_lock_init(&data->lock);
+
+ platform_set_drvdata(pdev, data);
+
+ pm_runtime_enable(dev);
+
+ return 0;
+}
+
+static const struct of_device_id sysmmu_of_match[] __initconst = {
+ { .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,
+ }
+};
+
+static inline void pgtable_flush(void *vastart, void *vaend)
+{
+ dmac_flush_range(vastart, vaend);
+ outer_flush_range(virt_to_phys(vastart),
+ virt_to_phys(vaend));
+}
+
+static struct iommu_domain *exynos_iommu_domain_alloc(unsigned type)
+{
+ struct exynos_iommu_domain *exynos_domain;
+ int i;
+
+ if (type != IOMMU_DOMAIN_UNMANAGED)
+ return NULL;
+
+ exynos_domain = kzalloc(sizeof(*exynos_domain), GFP_KERNEL);
+ if (!exynos_domain)
+ return NULL;
+
+ exynos_domain->pgtable = (sysmmu_pte_t *)__get_free_pages(GFP_KERNEL, 2);
+ if (!exynos_domain->pgtable)
+ goto err_pgtable;
+
+ exynos_domain->lv2entcnt = (short *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, 1);
+ if (!exynos_domain->lv2entcnt)
+ goto err_counter;
+
+ /* Workaround for System MMU v3.3 to prevent caching 1MiB mapping */
+ for (i = 0; i < NUM_LV1ENTRIES; i += 8) {
+ exynos_domain->pgtable[i + 0] = ZERO_LV2LINK;
+ exynos_domain->pgtable[i + 1] = ZERO_LV2LINK;
+ exynos_domain->pgtable[i + 2] = ZERO_LV2LINK;
+ exynos_domain->pgtable[i + 3] = ZERO_LV2LINK;
+ exynos_domain->pgtable[i + 4] = ZERO_LV2LINK;
+ exynos_domain->pgtable[i + 5] = ZERO_LV2LINK;
+ exynos_domain->pgtable[i + 6] = ZERO_LV2LINK;
+ exynos_domain->pgtable[i + 7] = ZERO_LV2LINK;
+ }
+
+ pgtable_flush(exynos_domain->pgtable, exynos_domain->pgtable + NUM_LV1ENTRIES);
+
+ spin_lock_init(&exynos_domain->lock);
+ spin_lock_init(&exynos_domain->pgtablelock);
+ INIT_LIST_HEAD(&exynos_domain->clients);
+
+ exynos_domain->domain.geometry.aperture_start = 0;
+ exynos_domain->domain.geometry.aperture_end = ~0UL;
+ exynos_domain->domain.geometry.force_aperture = true;
+
+ return &exynos_domain->domain;
+
+err_counter:
+ free_pages((unsigned long)exynos_domain->pgtable, 2);
+err_pgtable:
+ kfree(exynos_domain);
+ return NULL;
+}
+
+static void exynos_iommu_domain_free(struct iommu_domain *domain)
+{
+ struct exynos_iommu_domain *priv = to_exynos_domain(domain);
+ struct exynos_iommu_owner *owner;
+ unsigned long flags;
+ int i;
+
+ WARN_ON(!list_empty(&priv->clients));
+
+ spin_lock_irqsave(&priv->lock, flags);
+
+ list_for_each_entry(owner, &priv->clients, client) {
+ while (!exynos_sysmmu_disable(owner->dev))
+ ; /* until System MMU is actually disabled */
+ }
+
+ while (!list_empty(&priv->clients))
+ list_del_init(priv->clients.next);
+
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ for (i = 0; i < NUM_LV1ENTRIES; i++)
+ if (lv1ent_page(priv->pgtable + i))
+ kmem_cache_free(lv2table_kmem_cache,
+ phys_to_virt(lv2table_base(priv->pgtable + i)));
+
+ free_pages((unsigned long)priv->pgtable, 2);
+ free_pages((unsigned long)priv->lv2entcnt, 1);
+ kfree(priv);
+}
+
+static int exynos_iommu_attach_device(struct iommu_domain *domain,
+ struct device *dev)
+{
+ struct exynos_iommu_owner *owner = dev->archdata.iommu;
+ struct exynos_iommu_domain *priv = to_exynos_domain(domain);
+ phys_addr_t pagetable = virt_to_phys(priv->pgtable);
+ unsigned long flags;
+ int ret;
+
+ spin_lock_irqsave(&priv->lock, flags);
+
+ ret = __exynos_sysmmu_enable(dev, pagetable, domain);
+ if (ret == 0) {
+ list_add_tail(&owner->client, &priv->clients);
+ owner->domain = domain;
+ }
+
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ if (ret < 0) {
+ dev_err(dev, "%s: Failed to attach IOMMU with pgtable %pa\n",
+ __func__, &pagetable);
+ return ret;
+ }
+
+ dev_dbg(dev, "%s: Attached IOMMU with pgtable %pa %s\n",
+ __func__, &pagetable, (ret == 0) ? "" : ", again");
+
+ return ret;
+}
+
+static void exynos_iommu_detach_device(struct iommu_domain *domain,
+ struct device *dev)
+{
+ struct exynos_iommu_owner *owner;
+ struct exynos_iommu_domain *priv = to_exynos_domain(domain);
+ phys_addr_t pagetable = virt_to_phys(priv->pgtable);
+ unsigned long flags;
+
+ spin_lock_irqsave(&priv->lock, flags);
+
+ list_for_each_entry(owner, &priv->clients, client) {
+ if (owner == dev->archdata.iommu) {
+ if (exynos_sysmmu_disable(dev)) {
+ list_del_init(&owner->client);
+ owner->domain = NULL;
+ }
+ break;
+ }
+ }
+
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ if (owner == dev->archdata.iommu)
+ dev_dbg(dev, "%s: Detached IOMMU with pgtable %pa\n",
+ __func__, &pagetable);
+ else
+ dev_err(dev, "%s: No IOMMU is attached\n", __func__);
+}
+
+static sysmmu_pte_t *alloc_lv2entry(struct exynos_iommu_domain *priv,
+ 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)) {
+ sysmmu_pte_t *pent;
+ bool need_flush_flpd_cache = lv1ent_zero(sent);
+
+ pent = kmem_cache_zalloc(lv2table_kmem_cache, GFP_ATOMIC);
+ BUG_ON((unsigned int)pent & (LV2TABLE_SIZE - 1));
+ if (!pent)
+ return ERR_PTR(-ENOMEM);
+
+ *sent = mk_lv1ent_page(virt_to_phys(pent));
+ *pgcounter = NUM_LV2ENTRIES;
+ pgtable_flush(pent, pent + NUM_LV2ENTRIES);
+ pgtable_flush(sent, sent + 1);
+
+ /*
+ * 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 exynos_iommu_owner *owner;
+
+ spin_lock(&priv->lock);
+ list_for_each_entry(owner, &priv->clients, client)
+ sysmmu_tlb_invalidate_flpdcache(
+ owner->dev, iova);
+ spin_unlock(&priv->lock);
+ }
+ }
+
+ return page_entry(sent, iova);
+}
+
+static int lv1set_section(struct exynos_iommu_domain *priv,
+ sysmmu_pte_t *sent, sysmmu_iova_t iova,
+ phys_addr_t paddr, 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;
+ }
+
+ *sent = mk_lv1ent_sect(paddr);
+
+ pgtable_flush(sent, sent + 1);
+
+ spin_lock(&priv->lock);
+ if (lv1ent_page_zero(sent)) {
+ struct exynos_iommu_owner *owner;
+ /*
+ * 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(owner, &priv->clients, client)
+ sysmmu_tlb_invalidate_flpdcache(owner->dev, iova);
+ }
+ spin_unlock(&priv->lock);
+
+ return 0;
+}
+
+static int lv2set_page(sysmmu_pte_t *pent, phys_addr_t paddr, size_t size,
+ short *pgcnt)
+{
+ if (size == SPAGE_SIZE) {
+ if (WARN_ON(!lv2ent_fault(pent)))
+ return -EADDRINUSE;
+
+ *pent = mk_lv2ent_spage(paddr);
+ pgtable_flush(pent, pent + 1);
+ *pgcnt -= 1;
+ } else { /* size == LPAGE_SIZE */
+ int i;
+
+ 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);
+ }
+ pgtable_flush(pent - SPAGES_PER_LPAGE, pent);
+ *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 *domain, unsigned long l_iova,
+ phys_addr_t paddr, size_t size, int prot)
+{
+ struct exynos_iommu_domain *priv = to_exynos_domain(domain);
+ sysmmu_pte_t *entry;
+ sysmmu_iova_t iova = (sysmmu_iova_t)l_iova;
+ unsigned long flags;
+ int ret = -ENOMEM;
+
+ BUG_ON(priv->pgtable == NULL);
+
+ spin_lock_irqsave(&priv->pgtablelock, flags);
+
+ entry = section_entry(priv->pgtable, iova);
+
+ if (size == SECT_SIZE) {
+ ret = lv1set_section(priv, entry, iova, paddr,
+ &priv->lv2entcnt[lv1ent_offset(iova)]);
+ } else {
+ sysmmu_pte_t *pent;
+
+ pent = alloc_lv2entry(priv, entry, iova,
+ &priv->lv2entcnt[lv1ent_offset(iova)]);
+
+ if (IS_ERR(pent))
+ ret = PTR_ERR(pent);
+ else
+ ret = lv2set_page(pent, paddr, size,
+ &priv->lv2entcnt[lv1ent_offset(iova)]);
+ }
+
+ if (ret)
+ pr_err("%s: Failed(%d) to map %#zx bytes @ %#x\n",
+ __func__, ret, size, iova);
+
+ spin_unlock_irqrestore(&priv->pgtablelock, flags);
+
+ return ret;
+}
+
+static void exynos_iommu_tlb_invalidate_entry(struct exynos_iommu_domain *priv,
+ sysmmu_iova_t iova, size_t size)
+{
+ struct exynos_iommu_owner *owner;
+ unsigned long flags;
+
+ spin_lock_irqsave(&priv->lock, flags);
+
+ list_for_each_entry(owner, &priv->clients, client)
+ sysmmu_tlb_invalidate_entry(owner->dev, iova, size);
+
+ spin_unlock_irqrestore(&priv->lock, flags);
+}
+
+static size_t exynos_iommu_unmap(struct iommu_domain *domain,
+ unsigned long l_iova, size_t size)
+{
+ struct exynos_iommu_domain *priv = to_exynos_domain(domain);
+ sysmmu_iova_t iova = (sysmmu_iova_t)l_iova;
+ sysmmu_pte_t *ent;
+ size_t err_pgsize;
+ unsigned long flags;
+
+ BUG_ON(priv->pgtable == NULL);
+
+ spin_lock_irqsave(&priv->pgtablelock, flags);
+
+ ent = section_entry(priv->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 */
+ *ent = ZERO_LV2LINK;
+ pgtable_flush(ent, ent + 1);
+ 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)) {
+ *ent = 0;
+ size = SPAGE_SIZE;
+ pgtable_flush(ent, ent + 1);
+ priv->lv2entcnt[lv1ent_offset(iova)] += 1;
+ goto done;
+ }
+
+ /* lv1ent_large(ent) == true here */
+ if (WARN_ON(size < LPAGE_SIZE)) {
+ err_pgsize = LPAGE_SIZE;
+ goto err;
+ }
+
+ memset(ent, 0, sizeof(*ent) * SPAGES_PER_LPAGE);
+ pgtable_flush(ent, ent + SPAGES_PER_LPAGE);
+
+ size = LPAGE_SIZE;
+ priv->lv2entcnt[lv1ent_offset(iova)] += SPAGES_PER_LPAGE;
+done:
+ spin_unlock_irqrestore(&priv->pgtablelock, flags);
+
+ exynos_iommu_tlb_invalidate_entry(priv, iova, size);
+
+ return size;
+err:
+ spin_unlock_irqrestore(&priv->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 *domain,
+ dma_addr_t iova)
+{
+ struct exynos_iommu_domain *priv = to_exynos_domain(domain);
+ sysmmu_pte_t *entry;
+ unsigned long flags;
+ phys_addr_t phys = 0;
+
+ spin_lock_irqsave(&priv->pgtablelock, flags);
+
+ entry = section_entry(priv->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(&priv->pgtablelock, flags);
+
+ return phys;
+}
+
+static int exynos_iommu_add_device(struct device *dev)
+{
+ struct iommu_group *group;
+ int ret;
+
+ group = iommu_group_get(dev);
+
+ if (!group) {
+ group = iommu_group_alloc();
+ if (IS_ERR(group)) {
+ dev_err(dev, "Failed to allocate IOMMU group\n");
+ return PTR_ERR(group);
+ }
+ }
+
+ ret = iommu_group_add_device(group, dev);
+ iommu_group_put(group);
+
+ return ret;
+}
+
+static void exynos_iommu_remove_device(struct device *dev)
+{
+ iommu_group_remove_device(dev);
+}
+
+static const struct iommu_ops exynos_iommu_ops = {
+ .domain_alloc = exynos_iommu_domain_alloc,
+ .domain_free = exynos_iommu_domain_free,
+ .attach_dev = exynos_iommu_attach_device,
+ .detach_dev = exynos_iommu_detach_device,
+ .map = exynos_iommu_map,
+ .unmap = exynos_iommu_unmap,
+ .map_sg = default_iommu_map_sg,
+ .iova_to_phys = exynos_iommu_iova_to_phys,
+ .add_device = exynos_iommu_add_device,
+ .remove_device = exynos_iommu_remove_device,
+ .pgsize_bitmap = SECT_SIZE | LPAGE_SIZE | SPAGE_SIZE,
+};
+
+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;
+}
+subsys_initcall(exynos_iommu_init);
Code Review / kvmfornfv.git / blobdiff