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-rw-r--r--kernel/drivers/iommu/tegra-smmu.c747
1 files changed, 747 insertions, 0 deletions
diff --git a/kernel/drivers/iommu/tegra-smmu.c b/kernel/drivers/iommu/tegra-smmu.c
new file mode 100644
index 000000000..c845d99ec
--- /dev/null
+++ b/kernel/drivers/iommu/tegra-smmu.c
@@ -0,0 +1,747 @@
+/*
+ * Copyright (C) 2011-2014 NVIDIA CORPORATION. All rights reserved.
+ *
+ * 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.
+ */
+
+#include <linux/bitops.h>
+#include <linux/err.h>
+#include <linux/iommu.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#include <soc/tegra/ahb.h>
+#include <soc/tegra/mc.h>
+
+struct tegra_smmu {
+ void __iomem *regs;
+ struct device *dev;
+
+ struct tegra_mc *mc;
+ const struct tegra_smmu_soc *soc;
+
+ unsigned long pfn_mask;
+
+ unsigned long *asids;
+ struct mutex lock;
+
+ struct list_head list;
+};
+
+struct tegra_smmu_as {
+ struct iommu_domain domain;
+ struct tegra_smmu *smmu;
+ unsigned int use_count;
+ struct page *count;
+ struct page *pd;
+ unsigned id;
+ u32 attr;
+};
+
+static struct tegra_smmu_as *to_smmu_as(struct iommu_domain *dom)
+{
+ return container_of(dom, struct tegra_smmu_as, domain);
+}
+
+static inline void smmu_writel(struct tegra_smmu *smmu, u32 value,
+ unsigned long offset)
+{
+ writel(value, smmu->regs + offset);
+}
+
+static inline u32 smmu_readl(struct tegra_smmu *smmu, unsigned long offset)
+{
+ return readl(smmu->regs + offset);
+}
+
+#define SMMU_CONFIG 0x010
+#define SMMU_CONFIG_ENABLE (1 << 0)
+
+#define SMMU_TLB_CONFIG 0x14
+#define SMMU_TLB_CONFIG_HIT_UNDER_MISS (1 << 29)
+#define SMMU_TLB_CONFIG_ROUND_ROBIN_ARBITRATION (1 << 28)
+#define SMMU_TLB_CONFIG_ACTIVE_LINES(x) ((x) & 0x3f)
+
+#define SMMU_PTC_CONFIG 0x18
+#define SMMU_PTC_CONFIG_ENABLE (1 << 29)
+#define SMMU_PTC_CONFIG_REQ_LIMIT(x) (((x) & 0x0f) << 24)
+#define SMMU_PTC_CONFIG_INDEX_MAP(x) ((x) & 0x3f)
+
+#define SMMU_PTB_ASID 0x01c
+#define SMMU_PTB_ASID_VALUE(x) ((x) & 0x7f)
+
+#define SMMU_PTB_DATA 0x020
+#define SMMU_PTB_DATA_VALUE(page, attr) (page_to_phys(page) >> 12 | (attr))
+
+#define SMMU_MK_PDE(page, attr) (page_to_phys(page) >> SMMU_PTE_SHIFT | (attr))
+
+#define SMMU_TLB_FLUSH 0x030
+#define SMMU_TLB_FLUSH_VA_MATCH_ALL (0 << 0)
+#define SMMU_TLB_FLUSH_VA_MATCH_SECTION (2 << 0)
+#define SMMU_TLB_FLUSH_VA_MATCH_GROUP (3 << 0)
+#define SMMU_TLB_FLUSH_ASID(x) (((x) & 0x7f) << 24)
+#define SMMU_TLB_FLUSH_VA_SECTION(addr) ((((addr) & 0xffc00000) >> 12) | \
+ SMMU_TLB_FLUSH_VA_MATCH_SECTION)
+#define SMMU_TLB_FLUSH_VA_GROUP(addr) ((((addr) & 0xffffc000) >> 12) | \
+ SMMU_TLB_FLUSH_VA_MATCH_GROUP)
+#define SMMU_TLB_FLUSH_ASID_MATCH (1 << 31)
+
+#define SMMU_PTC_FLUSH 0x034
+#define SMMU_PTC_FLUSH_TYPE_ALL (0 << 0)
+#define SMMU_PTC_FLUSH_TYPE_ADR (1 << 0)
+
+#define SMMU_PTC_FLUSH_HI 0x9b8
+#define SMMU_PTC_FLUSH_HI_MASK 0x3
+
+/* per-SWGROUP SMMU_*_ASID register */
+#define SMMU_ASID_ENABLE (1 << 31)
+#define SMMU_ASID_MASK 0x7f
+#define SMMU_ASID_VALUE(x) ((x) & SMMU_ASID_MASK)
+
+/* page table definitions */
+#define SMMU_NUM_PDE 1024
+#define SMMU_NUM_PTE 1024
+
+#define SMMU_SIZE_PD (SMMU_NUM_PDE * 4)
+#define SMMU_SIZE_PT (SMMU_NUM_PTE * 4)
+
+#define SMMU_PDE_SHIFT 22
+#define SMMU_PTE_SHIFT 12
+
+#define SMMU_PD_READABLE (1 << 31)
+#define SMMU_PD_WRITABLE (1 << 30)
+#define SMMU_PD_NONSECURE (1 << 29)
+
+#define SMMU_PDE_READABLE (1 << 31)
+#define SMMU_PDE_WRITABLE (1 << 30)
+#define SMMU_PDE_NONSECURE (1 << 29)
+#define SMMU_PDE_NEXT (1 << 28)
+
+#define SMMU_PTE_READABLE (1 << 31)
+#define SMMU_PTE_WRITABLE (1 << 30)
+#define SMMU_PTE_NONSECURE (1 << 29)
+
+#define SMMU_PDE_ATTR (SMMU_PDE_READABLE | SMMU_PDE_WRITABLE | \
+ SMMU_PDE_NONSECURE)
+#define SMMU_PTE_ATTR (SMMU_PTE_READABLE | SMMU_PTE_WRITABLE | \
+ SMMU_PTE_NONSECURE)
+
+static inline void smmu_flush_ptc(struct tegra_smmu *smmu, struct page *page,
+ unsigned long offset)
+{
+ phys_addr_t phys = page ? page_to_phys(page) : 0;
+ u32 value;
+
+ if (page) {
+ offset &= ~(smmu->mc->soc->atom_size - 1);
+
+ if (smmu->mc->soc->num_address_bits > 32) {
+#ifdef CONFIG_PHYS_ADDR_T_64BIT
+ value = (phys >> 32) & SMMU_PTC_FLUSH_HI_MASK;
+#else
+ value = 0;
+#endif
+ smmu_writel(smmu, value, SMMU_PTC_FLUSH_HI);
+ }
+
+ value = (phys + offset) | SMMU_PTC_FLUSH_TYPE_ADR;
+ } else {
+ value = SMMU_PTC_FLUSH_TYPE_ALL;
+ }
+
+ smmu_writel(smmu, value, SMMU_PTC_FLUSH);
+}
+
+static inline void smmu_flush_tlb(struct tegra_smmu *smmu)
+{
+ smmu_writel(smmu, SMMU_TLB_FLUSH_VA_MATCH_ALL, SMMU_TLB_FLUSH);
+}
+
+static inline void smmu_flush_tlb_asid(struct tegra_smmu *smmu,
+ unsigned long asid)
+{
+ u32 value;
+
+ value = SMMU_TLB_FLUSH_ASID_MATCH | SMMU_TLB_FLUSH_ASID(asid) |
+ SMMU_TLB_FLUSH_VA_MATCH_ALL;
+ smmu_writel(smmu, value, SMMU_TLB_FLUSH);
+}
+
+static inline void smmu_flush_tlb_section(struct tegra_smmu *smmu,
+ unsigned long asid,
+ unsigned long iova)
+{
+ u32 value;
+
+ value = SMMU_TLB_FLUSH_ASID_MATCH | SMMU_TLB_FLUSH_ASID(asid) |
+ SMMU_TLB_FLUSH_VA_SECTION(iova);
+ smmu_writel(smmu, value, SMMU_TLB_FLUSH);
+}
+
+static inline void smmu_flush_tlb_group(struct tegra_smmu *smmu,
+ unsigned long asid,
+ unsigned long iova)
+{
+ u32 value;
+
+ value = SMMU_TLB_FLUSH_ASID_MATCH | SMMU_TLB_FLUSH_ASID(asid) |
+ SMMU_TLB_FLUSH_VA_GROUP(iova);
+ smmu_writel(smmu, value, SMMU_TLB_FLUSH);
+}
+
+static inline void smmu_flush(struct tegra_smmu *smmu)
+{
+ smmu_readl(smmu, SMMU_CONFIG);
+}
+
+static int tegra_smmu_alloc_asid(struct tegra_smmu *smmu, unsigned int *idp)
+{
+ unsigned long id;
+
+ mutex_lock(&smmu->lock);
+
+ id = find_first_zero_bit(smmu->asids, smmu->soc->num_asids);
+ if (id >= smmu->soc->num_asids) {
+ mutex_unlock(&smmu->lock);
+ return -ENOSPC;
+ }
+
+ set_bit(id, smmu->asids);
+ *idp = id;
+
+ mutex_unlock(&smmu->lock);
+ return 0;
+}
+
+static void tegra_smmu_free_asid(struct tegra_smmu *smmu, unsigned int id)
+{
+ mutex_lock(&smmu->lock);
+ clear_bit(id, smmu->asids);
+ mutex_unlock(&smmu->lock);
+}
+
+static bool tegra_smmu_capable(enum iommu_cap cap)
+{
+ return false;
+}
+
+static struct iommu_domain *tegra_smmu_domain_alloc(unsigned type)
+{
+ struct tegra_smmu_as *as;
+ unsigned int i;
+ uint32_t *pd;
+
+ if (type != IOMMU_DOMAIN_UNMANAGED)
+ return NULL;
+
+ as = kzalloc(sizeof(*as), GFP_KERNEL);
+ if (!as)
+ return NULL;
+
+ as->attr = SMMU_PD_READABLE | SMMU_PD_WRITABLE | SMMU_PD_NONSECURE;
+
+ as->pd = alloc_page(GFP_KERNEL | __GFP_DMA);
+ if (!as->pd) {
+ kfree(as);
+ return NULL;
+ }
+
+ as->count = alloc_page(GFP_KERNEL);
+ if (!as->count) {
+ __free_page(as->pd);
+ kfree(as);
+ return NULL;
+ }
+
+ /* clear PDEs */
+ pd = page_address(as->pd);
+ SetPageReserved(as->pd);
+
+ for (i = 0; i < SMMU_NUM_PDE; i++)
+ pd[i] = 0;
+
+ /* clear PDE usage counters */
+ pd = page_address(as->count);
+ SetPageReserved(as->count);
+
+ for (i = 0; i < SMMU_NUM_PDE; i++)
+ pd[i] = 0;
+
+ /* setup aperture */
+ as->domain.geometry.aperture_start = 0;
+ as->domain.geometry.aperture_end = 0xffffffff;
+ as->domain.geometry.force_aperture = true;
+
+ return &as->domain;
+}
+
+static void tegra_smmu_domain_free(struct iommu_domain *domain)
+{
+ struct tegra_smmu_as *as = to_smmu_as(domain);
+
+ /* TODO: free page directory and page tables */
+ ClearPageReserved(as->pd);
+
+ kfree(as);
+}
+
+static const struct tegra_smmu_swgroup *
+tegra_smmu_find_swgroup(struct tegra_smmu *smmu, unsigned int swgroup)
+{
+ const struct tegra_smmu_swgroup *group = NULL;
+ unsigned int i;
+
+ for (i = 0; i < smmu->soc->num_swgroups; i++) {
+ if (smmu->soc->swgroups[i].swgroup == swgroup) {
+ group = &smmu->soc->swgroups[i];
+ break;
+ }
+ }
+
+ return group;
+}
+
+static void tegra_smmu_enable(struct tegra_smmu *smmu, unsigned int swgroup,
+ unsigned int asid)
+{
+ const struct tegra_smmu_swgroup *group;
+ unsigned int i;
+ u32 value;
+
+ for (i = 0; i < smmu->soc->num_clients; i++) {
+ const struct tegra_mc_client *client = &smmu->soc->clients[i];
+
+ if (client->swgroup != swgroup)
+ continue;
+
+ value = smmu_readl(smmu, client->smmu.reg);
+ value |= BIT(client->smmu.bit);
+ smmu_writel(smmu, value, client->smmu.reg);
+ }
+
+ group = tegra_smmu_find_swgroup(smmu, swgroup);
+ if (group) {
+ value = smmu_readl(smmu, group->reg);
+ value &= ~SMMU_ASID_MASK;
+ value |= SMMU_ASID_VALUE(asid);
+ value |= SMMU_ASID_ENABLE;
+ smmu_writel(smmu, value, group->reg);
+ }
+}
+
+static void tegra_smmu_disable(struct tegra_smmu *smmu, unsigned int swgroup,
+ unsigned int asid)
+{
+ const struct tegra_smmu_swgroup *group;
+ unsigned int i;
+ u32 value;
+
+ group = tegra_smmu_find_swgroup(smmu, swgroup);
+ if (group) {
+ value = smmu_readl(smmu, group->reg);
+ value &= ~SMMU_ASID_MASK;
+ value |= SMMU_ASID_VALUE(asid);
+ value &= ~SMMU_ASID_ENABLE;
+ smmu_writel(smmu, value, group->reg);
+ }
+
+ for (i = 0; i < smmu->soc->num_clients; i++) {
+ const struct tegra_mc_client *client = &smmu->soc->clients[i];
+
+ if (client->swgroup != swgroup)
+ continue;
+
+ value = smmu_readl(smmu, client->smmu.reg);
+ value &= ~BIT(client->smmu.bit);
+ smmu_writel(smmu, value, client->smmu.reg);
+ }
+}
+
+static int tegra_smmu_as_prepare(struct tegra_smmu *smmu,
+ struct tegra_smmu_as *as)
+{
+ u32 value;
+ int err;
+
+ if (as->use_count > 0) {
+ as->use_count++;
+ return 0;
+ }
+
+ err = tegra_smmu_alloc_asid(smmu, &as->id);
+ if (err < 0)
+ return err;
+
+ smmu->soc->ops->flush_dcache(as->pd, 0, SMMU_SIZE_PD);
+ smmu_flush_ptc(smmu, as->pd, 0);
+ smmu_flush_tlb_asid(smmu, as->id);
+
+ smmu_writel(smmu, as->id & 0x7f, SMMU_PTB_ASID);
+ value = SMMU_PTB_DATA_VALUE(as->pd, as->attr);
+ smmu_writel(smmu, value, SMMU_PTB_DATA);
+ smmu_flush(smmu);
+
+ as->smmu = smmu;
+ as->use_count++;
+
+ return 0;
+}
+
+static void tegra_smmu_as_unprepare(struct tegra_smmu *smmu,
+ struct tegra_smmu_as *as)
+{
+ if (--as->use_count > 0)
+ return;
+
+ tegra_smmu_free_asid(smmu, as->id);
+ as->smmu = NULL;
+}
+
+static int tegra_smmu_attach_dev(struct iommu_domain *domain,
+ struct device *dev)
+{
+ struct tegra_smmu *smmu = dev->archdata.iommu;
+ struct tegra_smmu_as *as = to_smmu_as(domain);
+ struct device_node *np = dev->of_node;
+ struct of_phandle_args args;
+ unsigned int index = 0;
+ int err = 0;
+
+ while (!of_parse_phandle_with_args(np, "iommus", "#iommu-cells", index,
+ &args)) {
+ unsigned int swgroup = args.args[0];
+
+ if (args.np != smmu->dev->of_node) {
+ of_node_put(args.np);
+ continue;
+ }
+
+ of_node_put(args.np);
+
+ err = tegra_smmu_as_prepare(smmu, as);
+ if (err < 0)
+ return err;
+
+ tegra_smmu_enable(smmu, swgroup, as->id);
+ index++;
+ }
+
+ if (index == 0)
+ return -ENODEV;
+
+ return 0;
+}
+
+static void tegra_smmu_detach_dev(struct iommu_domain *domain, struct device *dev)
+{
+ struct tegra_smmu_as *as = to_smmu_as(domain);
+ struct device_node *np = dev->of_node;
+ struct tegra_smmu *smmu = as->smmu;
+ struct of_phandle_args args;
+ unsigned int index = 0;
+
+ while (!of_parse_phandle_with_args(np, "iommus", "#iommu-cells", index,
+ &args)) {
+ unsigned int swgroup = args.args[0];
+
+ if (args.np != smmu->dev->of_node) {
+ of_node_put(args.np);
+ continue;
+ }
+
+ of_node_put(args.np);
+
+ tegra_smmu_disable(smmu, swgroup, as->id);
+ tegra_smmu_as_unprepare(smmu, as);
+ index++;
+ }
+}
+
+static u32 *as_get_pte(struct tegra_smmu_as *as, dma_addr_t iova,
+ struct page **pagep)
+{
+ u32 *pd = page_address(as->pd), *pt, *count;
+ u32 pde = (iova >> SMMU_PDE_SHIFT) & 0x3ff;
+ u32 pte = (iova >> SMMU_PTE_SHIFT) & 0x3ff;
+ struct tegra_smmu *smmu = as->smmu;
+ struct page *page;
+ unsigned int i;
+
+ if (pd[pde] == 0) {
+ page = alloc_page(GFP_KERNEL | __GFP_DMA);
+ if (!page)
+ return NULL;
+
+ pt = page_address(page);
+ SetPageReserved(page);
+
+ for (i = 0; i < SMMU_NUM_PTE; i++)
+ pt[i] = 0;
+
+ smmu->soc->ops->flush_dcache(page, 0, SMMU_SIZE_PT);
+
+ pd[pde] = SMMU_MK_PDE(page, SMMU_PDE_ATTR | SMMU_PDE_NEXT);
+
+ smmu->soc->ops->flush_dcache(as->pd, pde << 2, 4);
+ smmu_flush_ptc(smmu, as->pd, pde << 2);
+ smmu_flush_tlb_section(smmu, as->id, iova);
+ smmu_flush(smmu);
+ } else {
+ page = pfn_to_page(pd[pde] & smmu->pfn_mask);
+ pt = page_address(page);
+ }
+
+ *pagep = page;
+
+ /* Keep track of entries in this page table. */
+ count = page_address(as->count);
+ if (pt[pte] == 0)
+ count[pde]++;
+
+ return &pt[pte];
+}
+
+static void as_put_pte(struct tegra_smmu_as *as, dma_addr_t iova)
+{
+ u32 pde = (iova >> SMMU_PDE_SHIFT) & 0x3ff;
+ u32 pte = (iova >> SMMU_PTE_SHIFT) & 0x3ff;
+ u32 *count = page_address(as->count);
+ u32 *pd = page_address(as->pd), *pt;
+ struct page *page;
+
+ page = pfn_to_page(pd[pde] & as->smmu->pfn_mask);
+ pt = page_address(page);
+
+ /*
+ * When no entries in this page table are used anymore, return the
+ * memory page to the system.
+ */
+ if (pt[pte] != 0) {
+ if (--count[pde] == 0) {
+ ClearPageReserved(page);
+ __free_page(page);
+ pd[pde] = 0;
+ }
+
+ pt[pte] = 0;
+ }
+}
+
+static int tegra_smmu_map(struct iommu_domain *domain, unsigned long iova,
+ phys_addr_t paddr, size_t size, int prot)
+{
+ struct tegra_smmu_as *as = to_smmu_as(domain);
+ struct tegra_smmu *smmu = as->smmu;
+ unsigned long offset;
+ struct page *page;
+ u32 *pte;
+
+ pte = as_get_pte(as, iova, &page);
+ if (!pte)
+ return -ENOMEM;
+
+ *pte = __phys_to_pfn(paddr) | SMMU_PTE_ATTR;
+ offset = offset_in_page(pte);
+
+ smmu->soc->ops->flush_dcache(page, offset, 4);
+ smmu_flush_ptc(smmu, page, offset);
+ smmu_flush_tlb_group(smmu, as->id, iova);
+ smmu_flush(smmu);
+
+ return 0;
+}
+
+static size_t tegra_smmu_unmap(struct iommu_domain *domain, unsigned long iova,
+ size_t size)
+{
+ struct tegra_smmu_as *as = to_smmu_as(domain);
+ struct tegra_smmu *smmu = as->smmu;
+ unsigned long offset;
+ struct page *page;
+ u32 *pte;
+
+ pte = as_get_pte(as, iova, &page);
+ if (!pte)
+ return 0;
+
+ offset = offset_in_page(pte);
+ as_put_pte(as, iova);
+
+ smmu->soc->ops->flush_dcache(page, offset, 4);
+ smmu_flush_ptc(smmu, page, offset);
+ smmu_flush_tlb_group(smmu, as->id, iova);
+ smmu_flush(smmu);
+
+ return size;
+}
+
+static phys_addr_t tegra_smmu_iova_to_phys(struct iommu_domain *domain,
+ dma_addr_t iova)
+{
+ struct tegra_smmu_as *as = to_smmu_as(domain);
+ struct page *page;
+ unsigned long pfn;
+ u32 *pte;
+
+ pte = as_get_pte(as, iova, &page);
+ pfn = *pte & as->smmu->pfn_mask;
+
+ return PFN_PHYS(pfn);
+}
+
+static struct tegra_smmu *tegra_smmu_find(struct device_node *np)
+{
+ struct platform_device *pdev;
+ struct tegra_mc *mc;
+
+ pdev = of_find_device_by_node(np);
+ if (!pdev)
+ return NULL;
+
+ mc = platform_get_drvdata(pdev);
+ if (!mc)
+ return NULL;
+
+ return mc->smmu;
+}
+
+static int tegra_smmu_add_device(struct device *dev)
+{
+ struct device_node *np = dev->of_node;
+ struct of_phandle_args args;
+ unsigned int index = 0;
+
+ while (of_parse_phandle_with_args(np, "iommus", "#iommu-cells", index,
+ &args) == 0) {
+ struct tegra_smmu *smmu;
+
+ smmu = tegra_smmu_find(args.np);
+ if (smmu) {
+ /*
+ * Only a single IOMMU master interface is currently
+ * supported by the Linux kernel, so abort after the
+ * first match.
+ */
+ dev->archdata.iommu = smmu;
+ break;
+ }
+
+ index++;
+ }
+
+ return 0;
+}
+
+static void tegra_smmu_remove_device(struct device *dev)
+{
+ dev->archdata.iommu = NULL;
+}
+
+static const struct iommu_ops tegra_smmu_ops = {
+ .capable = tegra_smmu_capable,
+ .domain_alloc = tegra_smmu_domain_alloc,
+ .domain_free = tegra_smmu_domain_free,
+ .attach_dev = tegra_smmu_attach_dev,
+ .detach_dev = tegra_smmu_detach_dev,
+ .add_device = tegra_smmu_add_device,
+ .remove_device = tegra_smmu_remove_device,
+ .map = tegra_smmu_map,
+ .unmap = tegra_smmu_unmap,
+ .map_sg = default_iommu_map_sg,
+ .iova_to_phys = tegra_smmu_iova_to_phys,
+
+ .pgsize_bitmap = SZ_4K,
+};
+
+static void tegra_smmu_ahb_enable(void)
+{
+ static const struct of_device_id ahb_match[] = {
+ { .compatible = "nvidia,tegra30-ahb", },
+ { }
+ };
+ struct device_node *ahb;
+
+ ahb = of_find_matching_node(NULL, ahb_match);
+ if (ahb) {
+ tegra_ahb_enable_smmu(ahb);
+ of_node_put(ahb);
+ }
+}
+
+struct tegra_smmu *tegra_smmu_probe(struct device *dev,
+ const struct tegra_smmu_soc *soc,
+ struct tegra_mc *mc)
+{
+ struct tegra_smmu *smmu;
+ size_t size;
+ u32 value;
+ int err;
+
+ /* This can happen on Tegra20 which doesn't have an SMMU */
+ if (!soc)
+ return NULL;
+
+ smmu = devm_kzalloc(dev, sizeof(*smmu), GFP_KERNEL);
+ if (!smmu)
+ return ERR_PTR(-ENOMEM);
+
+ /*
+ * This is a bit of a hack. Ideally we'd want to simply return this
+ * value. However the IOMMU registration process will attempt to add
+ * all devices to the IOMMU when bus_set_iommu() is called. In order
+ * not to rely on global variables to track the IOMMU instance, we
+ * set it here so that it can be looked up from the .add_device()
+ * callback via the IOMMU device's .drvdata field.
+ */
+ mc->smmu = smmu;
+
+ size = BITS_TO_LONGS(soc->num_asids) * sizeof(long);
+
+ smmu->asids = devm_kzalloc(dev, size, GFP_KERNEL);
+ if (!smmu->asids)
+ return ERR_PTR(-ENOMEM);
+
+ mutex_init(&smmu->lock);
+
+ smmu->regs = mc->regs;
+ smmu->soc = soc;
+ smmu->dev = dev;
+ smmu->mc = mc;
+
+ smmu->pfn_mask = BIT_MASK(mc->soc->num_address_bits - PAGE_SHIFT) - 1;
+ dev_dbg(dev, "address bits: %u, PFN mask: %#lx\n",
+ mc->soc->num_address_bits, smmu->pfn_mask);
+
+ value = SMMU_PTC_CONFIG_ENABLE | SMMU_PTC_CONFIG_INDEX_MAP(0x3f);
+
+ if (soc->supports_request_limit)
+ value |= SMMU_PTC_CONFIG_REQ_LIMIT(8);
+
+ smmu_writel(smmu, value, SMMU_PTC_CONFIG);
+
+ value = SMMU_TLB_CONFIG_HIT_UNDER_MISS |
+ SMMU_TLB_CONFIG_ACTIVE_LINES(0x20);
+
+ if (soc->supports_round_robin_arbitration)
+ value |= SMMU_TLB_CONFIG_ROUND_ROBIN_ARBITRATION;
+
+ smmu_writel(smmu, value, SMMU_TLB_CONFIG);
+
+ smmu_flush_ptc(smmu, NULL, 0);
+ smmu_flush_tlb(smmu);
+ smmu_writel(smmu, SMMU_CONFIG_ENABLE, SMMU_CONFIG);
+ smmu_flush(smmu);
+
+ tegra_smmu_ahb_enable();
+
+ err = bus_set_iommu(&platform_bus_type, &tegra_smmu_ops);
+ if (err < 0)
+ return ERR_PTR(err);
+
+ return smmu;
+}