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-rw-r--r--drivers/iommu/tegra-smmu.c1159
1 files changed, 1159 insertions, 0 deletions
diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
new file mode 100644
index 000000000..5b1af4022
--- /dev/null
+++ b/drivers/iommu/tegra-smmu.c
@@ -0,0 +1,1159 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2011-2014 NVIDIA CORPORATION. All rights reserved.
+ */
+
+#include <linux/bitops.h>
+#include <linux/debugfs.h>
+#include <linux/err.h>
+#include <linux/iommu.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/dma-mapping.h>
+
+#include <soc/tegra/ahb.h>
+#include <soc/tegra/mc.h>
+
+struct tegra_smmu_group {
+ struct list_head list;
+ struct tegra_smmu *smmu;
+ const struct tegra_smmu_group_soc *soc;
+ struct iommu_group *group;
+ unsigned int swgroup;
+};
+
+struct tegra_smmu {
+ void __iomem *regs;
+ struct device *dev;
+
+ struct tegra_mc *mc;
+ const struct tegra_smmu_soc *soc;
+
+ struct list_head groups;
+
+ unsigned long pfn_mask;
+ unsigned long tlb_mask;
+
+ unsigned long *asids;
+ struct mutex lock;
+
+ struct list_head list;
+
+ struct dentry *debugfs;
+
+ struct iommu_device iommu; /* IOMMU Core code handle */
+};
+
+struct tegra_smmu_as {
+ struct iommu_domain domain;
+ struct tegra_smmu *smmu;
+ unsigned int use_count;
+ spinlock_t lock;
+ u32 *count;
+ struct page **pts;
+ struct page *pd;
+ dma_addr_t pd_dma;
+ 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(smmu) \
+ ((smmu)->soc->num_tlb_lines & (smmu)->tlb_mask)
+
+#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(dma, attr) ((dma) >> 12 | (attr))
+
+#define SMMU_MK_PDE(dma, attr) ((dma) >> 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_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_PAGE_MASK (~(SMMU_SIZE_PT-1))
+#define SMMU_OFFSET_IN_PAGE(x) ((unsigned long)(x) & ~SMMU_PAGE_MASK)
+#define SMMU_PFN_PHYS(x) ((phys_addr_t)(x) << SMMU_PTE_SHIFT)
+#define SMMU_PHYS_PFN(x) ((unsigned long)((x) >> SMMU_PTE_SHIFT))
+
+#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)
+
+static unsigned int iova_pd_index(unsigned long iova)
+{
+ return (iova >> SMMU_PDE_SHIFT) & (SMMU_NUM_PDE - 1);
+}
+
+static unsigned int iova_pt_index(unsigned long iova)
+{
+ return (iova >> SMMU_PTE_SHIFT) & (SMMU_NUM_PTE - 1);
+}
+
+static bool smmu_dma_addr_valid(struct tegra_smmu *smmu, dma_addr_t addr)
+{
+ addr >>= 12;
+ return (addr & smmu->pfn_mask) == addr;
+}
+
+static dma_addr_t smmu_pde_to_dma(struct tegra_smmu *smmu, u32 pde)
+{
+ return (dma_addr_t)(pde & smmu->pfn_mask) << 12;
+}
+
+static void smmu_flush_ptc_all(struct tegra_smmu *smmu)
+{
+ smmu_writel(smmu, SMMU_PTC_FLUSH_TYPE_ALL, SMMU_PTC_FLUSH);
+}
+
+static inline void smmu_flush_ptc(struct tegra_smmu *smmu, dma_addr_t dma,
+ unsigned long offset)
+{
+ u32 value;
+
+ offset &= ~(smmu->mc->soc->atom_size - 1);
+
+ if (smmu->mc->soc->num_address_bits > 32) {
+#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
+ value = (dma >> 32) & SMMU_PTC_FLUSH_HI_MASK;
+#else
+ value = 0;
+#endif
+ smmu_writel(smmu, value, SMMU_PTC_FLUSH_HI);
+ }
+
+ value = (dma + offset) | SMMU_PTC_FLUSH_TYPE_ADR;
+ 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;
+
+ if (smmu->soc->num_asids == 4)
+ value = (asid & 0x3) << 29;
+ else
+ value = (asid & 0x7f) << 24;
+
+ value |= SMMU_TLB_FLUSH_ASID_MATCH | 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;
+
+ if (smmu->soc->num_asids == 4)
+ value = (asid & 0x3) << 29;
+ else
+ value = (asid & 0x7f) << 24;
+
+ value |= SMMU_TLB_FLUSH_ASID_MATCH | 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;
+
+ if (smmu->soc->num_asids == 4)
+ value = (asid & 0x3) << 29;
+ else
+ value = (asid & 0x7f) << 24;
+
+ value |= SMMU_TLB_FLUSH_ASID_MATCH | 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_PTB_ASID);
+}
+
+static int tegra_smmu_alloc_asid(struct tegra_smmu *smmu, unsigned int *idp)
+{
+ unsigned long id;
+
+ id = find_first_zero_bit(smmu->asids, smmu->soc->num_asids);
+ if (id >= smmu->soc->num_asids)
+ return -ENOSPC;
+
+ set_bit(id, smmu->asids);
+ *idp = id;
+
+ return 0;
+}
+
+static void tegra_smmu_free_asid(struct tegra_smmu *smmu, unsigned int id)
+{
+ clear_bit(id, smmu->asids);
+}
+
+static struct iommu_domain *tegra_smmu_domain_alloc(unsigned type)
+{
+ struct tegra_smmu_as *as;
+
+ 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 | __GFP_ZERO);
+ if (!as->pd) {
+ kfree(as);
+ return NULL;
+ }
+
+ as->count = kcalloc(SMMU_NUM_PDE, sizeof(u32), GFP_KERNEL);
+ if (!as->count) {
+ __free_page(as->pd);
+ kfree(as);
+ return NULL;
+ }
+
+ as->pts = kcalloc(SMMU_NUM_PDE, sizeof(*as->pts), GFP_KERNEL);
+ if (!as->pts) {
+ kfree(as->count);
+ __free_page(as->pd);
+ kfree(as);
+ return NULL;
+ }
+
+ spin_lock_init(&as->lock);
+
+ /* 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 */
+
+ WARN_ON_ONCE(as->use_count);
+ kfree(as->count);
+ kfree(as->pts);
+ 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;
+
+ 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);
+ } else {
+ pr_warn("%s group from swgroup %u not found\n", __func__,
+ swgroup);
+ /* No point moving ahead if group was not found */
+ return;
+ }
+
+ 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->regs.smmu.reg);
+ value |= BIT(client->regs.smmu.bit);
+ smmu_writel(smmu, value, client->regs.smmu.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->regs.smmu.reg);
+ value &= ~BIT(client->regs.smmu.bit);
+ smmu_writel(smmu, value, client->regs.smmu.reg);
+ }
+}
+
+static int tegra_smmu_as_prepare(struct tegra_smmu *smmu,
+ struct tegra_smmu_as *as)
+{
+ u32 value;
+ int err = 0;
+
+ mutex_lock(&smmu->lock);
+
+ if (as->use_count > 0) {
+ as->use_count++;
+ goto unlock;
+ }
+
+ as->pd_dma = dma_map_page(smmu->dev, as->pd, 0, SMMU_SIZE_PD,
+ DMA_TO_DEVICE);
+ if (dma_mapping_error(smmu->dev, as->pd_dma)) {
+ err = -ENOMEM;
+ goto unlock;
+ }
+
+ /* We can't handle 64-bit DMA addresses */
+ if (!smmu_dma_addr_valid(smmu, as->pd_dma)) {
+ err = -ENOMEM;
+ goto err_unmap;
+ }
+
+ err = tegra_smmu_alloc_asid(smmu, &as->id);
+ if (err < 0)
+ goto err_unmap;
+
+ smmu_flush_ptc(smmu, as->pd_dma, 0);
+ smmu_flush_tlb_asid(smmu, as->id);
+
+ smmu_writel(smmu, as->id & 0x7f, SMMU_PTB_ASID);
+ value = SMMU_PTB_DATA_VALUE(as->pd_dma, as->attr);
+ smmu_writel(smmu, value, SMMU_PTB_DATA);
+ smmu_flush(smmu);
+
+ as->smmu = smmu;
+ as->use_count++;
+
+ mutex_unlock(&smmu->lock);
+
+ return 0;
+
+err_unmap:
+ dma_unmap_page(smmu->dev, as->pd_dma, SMMU_SIZE_PD, DMA_TO_DEVICE);
+unlock:
+ mutex_unlock(&smmu->lock);
+
+ return err;
+}
+
+static void tegra_smmu_as_unprepare(struct tegra_smmu *smmu,
+ struct tegra_smmu_as *as)
+{
+ mutex_lock(&smmu->lock);
+
+ if (--as->use_count > 0) {
+ mutex_unlock(&smmu->lock);
+ return;
+ }
+
+ tegra_smmu_free_asid(smmu, as->id);
+
+ dma_unmap_page(smmu->dev, as->pd_dma, SMMU_SIZE_PD, DMA_TO_DEVICE);
+
+ as->smmu = NULL;
+
+ mutex_unlock(&smmu->lock);
+}
+
+static int tegra_smmu_attach_dev(struct iommu_domain *domain,
+ struct device *dev)
+{
+ struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
+ struct tegra_smmu *smmu = dev_iommu_priv_get(dev);
+ struct tegra_smmu_as *as = to_smmu_as(domain);
+ unsigned int index;
+ int err;
+
+ if (!fwspec)
+ return -ENOENT;
+
+ for (index = 0; index < fwspec->num_ids; index++) {
+ err = tegra_smmu_as_prepare(smmu, as);
+ if (err)
+ goto disable;
+
+ tegra_smmu_enable(smmu, fwspec->ids[index], as->id);
+ }
+
+ if (index == 0)
+ return -ENODEV;
+
+ return 0;
+
+disable:
+ while (index--) {
+ tegra_smmu_disable(smmu, fwspec->ids[index], as->id);
+ tegra_smmu_as_unprepare(smmu, as);
+ }
+
+ return err;
+}
+
+static void tegra_smmu_detach_dev(struct iommu_domain *domain, struct device *dev)
+{
+ struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
+ struct tegra_smmu_as *as = to_smmu_as(domain);
+ struct tegra_smmu *smmu = as->smmu;
+ unsigned int index;
+
+ if (!fwspec)
+ return;
+
+ for (index = 0; index < fwspec->num_ids; index++) {
+ tegra_smmu_disable(smmu, fwspec->ids[index], as->id);
+ tegra_smmu_as_unprepare(smmu, as);
+ }
+}
+
+static void tegra_smmu_set_pde(struct tegra_smmu_as *as, unsigned long iova,
+ u32 value)
+{
+ unsigned int pd_index = iova_pd_index(iova);
+ struct tegra_smmu *smmu = as->smmu;
+ u32 *pd = page_address(as->pd);
+ unsigned long offset = pd_index * sizeof(*pd);
+
+ /* Set the page directory entry first */
+ pd[pd_index] = value;
+
+ /* The flush the page directory entry from caches */
+ dma_sync_single_range_for_device(smmu->dev, as->pd_dma, offset,
+ sizeof(*pd), DMA_TO_DEVICE);
+
+ /* And flush the iommu */
+ smmu_flush_ptc(smmu, as->pd_dma, offset);
+ smmu_flush_tlb_section(smmu, as->id, iova);
+ smmu_flush(smmu);
+}
+
+static u32 *tegra_smmu_pte_offset(struct page *pt_page, unsigned long iova)
+{
+ u32 *pt = page_address(pt_page);
+
+ return pt + iova_pt_index(iova);
+}
+
+static u32 *tegra_smmu_pte_lookup(struct tegra_smmu_as *as, unsigned long iova,
+ dma_addr_t *dmap)
+{
+ unsigned int pd_index = iova_pd_index(iova);
+ struct tegra_smmu *smmu = as->smmu;
+ struct page *pt_page;
+ u32 *pd;
+
+ pt_page = as->pts[pd_index];
+ if (!pt_page)
+ return NULL;
+
+ pd = page_address(as->pd);
+ *dmap = smmu_pde_to_dma(smmu, pd[pd_index]);
+
+ return tegra_smmu_pte_offset(pt_page, iova);
+}
+
+static u32 *as_get_pte(struct tegra_smmu_as *as, dma_addr_t iova,
+ dma_addr_t *dmap, struct page *page)
+{
+ unsigned int pde = iova_pd_index(iova);
+ struct tegra_smmu *smmu = as->smmu;
+
+ if (!as->pts[pde]) {
+ dma_addr_t dma;
+
+ dma = dma_map_page(smmu->dev, page, 0, SMMU_SIZE_PT,
+ DMA_TO_DEVICE);
+ if (dma_mapping_error(smmu->dev, dma)) {
+ __free_page(page);
+ return NULL;
+ }
+
+ if (!smmu_dma_addr_valid(smmu, dma)) {
+ dma_unmap_page(smmu->dev, dma, SMMU_SIZE_PT,
+ DMA_TO_DEVICE);
+ __free_page(page);
+ return NULL;
+ }
+
+ as->pts[pde] = page;
+
+ tegra_smmu_set_pde(as, iova, SMMU_MK_PDE(dma, SMMU_PDE_ATTR |
+ SMMU_PDE_NEXT));
+
+ *dmap = dma;
+ } else {
+ u32 *pd = page_address(as->pd);
+
+ *dmap = smmu_pde_to_dma(smmu, pd[pde]);
+ }
+
+ return tegra_smmu_pte_offset(as->pts[pde], iova);
+}
+
+static void tegra_smmu_pte_get_use(struct tegra_smmu_as *as, unsigned long iova)
+{
+ unsigned int pd_index = iova_pd_index(iova);
+
+ as->count[pd_index]++;
+}
+
+static void tegra_smmu_pte_put_use(struct tegra_smmu_as *as, unsigned long iova)
+{
+ unsigned int pde = iova_pd_index(iova);
+ struct page *page = as->pts[pde];
+
+ /*
+ * When no entries in this page table are used anymore, return the
+ * memory page to the system.
+ */
+ if (--as->count[pde] == 0) {
+ struct tegra_smmu *smmu = as->smmu;
+ u32 *pd = page_address(as->pd);
+ dma_addr_t pte_dma = smmu_pde_to_dma(smmu, pd[pde]);
+
+ tegra_smmu_set_pde(as, iova, 0);
+
+ dma_unmap_page(smmu->dev, pte_dma, SMMU_SIZE_PT, DMA_TO_DEVICE);
+ __free_page(page);
+ as->pts[pde] = NULL;
+ }
+}
+
+static void tegra_smmu_set_pte(struct tegra_smmu_as *as, unsigned long iova,
+ u32 *pte, dma_addr_t pte_dma, u32 val)
+{
+ struct tegra_smmu *smmu = as->smmu;
+ unsigned long offset = SMMU_OFFSET_IN_PAGE(pte);
+
+ *pte = val;
+
+ dma_sync_single_range_for_device(smmu->dev, pte_dma, offset,
+ 4, DMA_TO_DEVICE);
+ smmu_flush_ptc(smmu, pte_dma, offset);
+ smmu_flush_tlb_group(smmu, as->id, iova);
+ smmu_flush(smmu);
+}
+
+static struct page *as_get_pde_page(struct tegra_smmu_as *as,
+ unsigned long iova, gfp_t gfp,
+ unsigned long *flags)
+{
+ unsigned int pde = iova_pd_index(iova);
+ struct page *page = as->pts[pde];
+
+ /* at first check whether allocation needs to be done at all */
+ if (page)
+ return page;
+
+ /*
+ * In order to prevent exhaustion of the atomic memory pool, we
+ * allocate page in a sleeping context if GFP flags permit. Hence
+ * spinlock needs to be unlocked and re-locked after allocation.
+ */
+ if (!(gfp & __GFP_ATOMIC))
+ spin_unlock_irqrestore(&as->lock, *flags);
+
+ page = alloc_page(gfp | __GFP_DMA | __GFP_ZERO);
+
+ if (!(gfp & __GFP_ATOMIC))
+ spin_lock_irqsave(&as->lock, *flags);
+
+ /*
+ * In a case of blocking allocation, a concurrent mapping may win
+ * the PDE allocation. In this case the allocated page isn't needed
+ * if allocation succeeded and the allocation failure isn't fatal.
+ */
+ if (as->pts[pde]) {
+ if (page)
+ __free_page(page);
+
+ page = as->pts[pde];
+ }
+
+ return page;
+}
+
+static int
+__tegra_smmu_map(struct iommu_domain *domain, unsigned long iova,
+ phys_addr_t paddr, size_t size, int prot, gfp_t gfp,
+ unsigned long *flags)
+{
+ struct tegra_smmu_as *as = to_smmu_as(domain);
+ dma_addr_t pte_dma;
+ struct page *page;
+ u32 pte_attrs;
+ u32 *pte;
+
+ page = as_get_pde_page(as, iova, gfp, flags);
+ if (!page)
+ return -ENOMEM;
+
+ pte = as_get_pte(as, iova, &pte_dma, page);
+ if (!pte)
+ return -ENOMEM;
+
+ /* If we aren't overwriting a pre-existing entry, increment use */
+ if (*pte == 0)
+ tegra_smmu_pte_get_use(as, iova);
+
+ pte_attrs = SMMU_PTE_NONSECURE;
+
+ if (prot & IOMMU_READ)
+ pte_attrs |= SMMU_PTE_READABLE;
+
+ if (prot & IOMMU_WRITE)
+ pte_attrs |= SMMU_PTE_WRITABLE;
+
+ tegra_smmu_set_pte(as, iova, pte, pte_dma,
+ SMMU_PHYS_PFN(paddr) | pte_attrs);
+
+ return 0;
+}
+
+static size_t
+__tegra_smmu_unmap(struct iommu_domain *domain, unsigned long iova,
+ size_t size, struct iommu_iotlb_gather *gather)
+{
+ struct tegra_smmu_as *as = to_smmu_as(domain);
+ dma_addr_t pte_dma;
+ u32 *pte;
+
+ pte = tegra_smmu_pte_lookup(as, iova, &pte_dma);
+ if (!pte || !*pte)
+ return 0;
+
+ tegra_smmu_set_pte(as, iova, pte, pte_dma, 0);
+ tegra_smmu_pte_put_use(as, iova);
+
+ return size;
+}
+
+static int tegra_smmu_map(struct iommu_domain *domain, unsigned long iova,
+ phys_addr_t paddr, size_t size, int prot, gfp_t gfp)
+{
+ struct tegra_smmu_as *as = to_smmu_as(domain);
+ unsigned long flags;
+ int ret;
+
+ spin_lock_irqsave(&as->lock, flags);
+ ret = __tegra_smmu_map(domain, iova, paddr, size, prot, gfp, &flags);
+ spin_unlock_irqrestore(&as->lock, flags);
+
+ return ret;
+}
+
+static size_t tegra_smmu_unmap(struct iommu_domain *domain, unsigned long iova,
+ size_t size, struct iommu_iotlb_gather *gather)
+{
+ struct tegra_smmu_as *as = to_smmu_as(domain);
+ unsigned long flags;
+
+ spin_lock_irqsave(&as->lock, flags);
+ size = __tegra_smmu_unmap(domain, iova, size, gather);
+ spin_unlock_irqrestore(&as->lock, flags);
+
+ 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);
+ unsigned long pfn;
+ dma_addr_t pte_dma;
+ u32 *pte;
+
+ pte = tegra_smmu_pte_lookup(as, iova, &pte_dma);
+ if (!pte || !*pte)
+ return 0;
+
+ pfn = *pte & as->smmu->pfn_mask;
+
+ return SMMU_PFN_PHYS(pfn) + SMMU_OFFSET_IN_PAGE(iova);
+}
+
+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) {
+ put_device(&pdev->dev);
+ return NULL;
+ }
+
+ return mc->smmu;
+}
+
+static int tegra_smmu_configure(struct tegra_smmu *smmu, struct device *dev,
+ struct of_phandle_args *args)
+{
+ const struct iommu_ops *ops = smmu->iommu.ops;
+ int err;
+
+ err = iommu_fwspec_init(dev, &dev->of_node->fwnode, ops);
+ if (err < 0) {
+ dev_err(dev, "failed to initialize fwspec: %d\n", err);
+ return err;
+ }
+
+ err = ops->of_xlate(dev, args);
+ if (err < 0) {
+ dev_err(dev, "failed to parse SW group ID: %d\n", err);
+ iommu_fwspec_free(dev);
+ return err;
+ }
+
+ return 0;
+}
+
+static struct iommu_device *tegra_smmu_probe_device(struct device *dev)
+{
+ struct device_node *np = dev->of_node;
+ struct tegra_smmu *smmu = NULL;
+ struct of_phandle_args args;
+ unsigned int index = 0;
+ int err;
+
+ while (of_parse_phandle_with_args(np, "iommus", "#iommu-cells", index,
+ &args) == 0) {
+ smmu = tegra_smmu_find(args.np);
+ if (smmu) {
+ err = tegra_smmu_configure(smmu, dev, &args);
+
+ if (err < 0) {
+ of_node_put(args.np);
+ return ERR_PTR(err);
+ }
+ }
+
+ of_node_put(args.np);
+ index++;
+ }
+
+ smmu = dev_iommu_priv_get(dev);
+ if (!smmu)
+ return ERR_PTR(-ENODEV);
+
+ return &smmu->iommu;
+}
+
+static const struct tegra_smmu_group_soc *
+tegra_smmu_find_group(struct tegra_smmu *smmu, unsigned int swgroup)
+{
+ unsigned int i, j;
+
+ for (i = 0; i < smmu->soc->num_groups; i++)
+ for (j = 0; j < smmu->soc->groups[i].num_swgroups; j++)
+ if (smmu->soc->groups[i].swgroups[j] == swgroup)
+ return &smmu->soc->groups[i];
+
+ return NULL;
+}
+
+static void tegra_smmu_group_release(void *iommu_data)
+{
+ struct tegra_smmu_group *group = iommu_data;
+ struct tegra_smmu *smmu = group->smmu;
+
+ mutex_lock(&smmu->lock);
+ list_del(&group->list);
+ mutex_unlock(&smmu->lock);
+}
+
+static struct iommu_group *tegra_smmu_device_group(struct device *dev)
+{
+ struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
+ struct tegra_smmu *smmu = dev_iommu_priv_get(dev);
+ const struct tegra_smmu_group_soc *soc;
+ unsigned int swgroup = fwspec->ids[0];
+ struct tegra_smmu_group *group;
+ struct iommu_group *grp;
+
+ /* Find group_soc associating with swgroup */
+ soc = tegra_smmu_find_group(smmu, swgroup);
+
+ mutex_lock(&smmu->lock);
+
+ /* Find existing iommu_group associating with swgroup or group_soc */
+ list_for_each_entry(group, &smmu->groups, list)
+ if ((group->swgroup == swgroup) || (soc && group->soc == soc)) {
+ grp = iommu_group_ref_get(group->group);
+ mutex_unlock(&smmu->lock);
+ return grp;
+ }
+
+ group = devm_kzalloc(smmu->dev, sizeof(*group), GFP_KERNEL);
+ if (!group) {
+ mutex_unlock(&smmu->lock);
+ return NULL;
+ }
+
+ INIT_LIST_HEAD(&group->list);
+ group->swgroup = swgroup;
+ group->smmu = smmu;
+ group->soc = soc;
+
+ if (dev_is_pci(dev))
+ group->group = pci_device_group(dev);
+ else
+ group->group = generic_device_group(dev);
+
+ if (IS_ERR(group->group)) {
+ devm_kfree(smmu->dev, group);
+ mutex_unlock(&smmu->lock);
+ return NULL;
+ }
+
+ iommu_group_set_iommudata(group->group, group, tegra_smmu_group_release);
+ if (soc)
+ iommu_group_set_name(group->group, soc->name);
+ list_add_tail(&group->list, &smmu->groups);
+ mutex_unlock(&smmu->lock);
+
+ return group->group;
+}
+
+static int tegra_smmu_of_xlate(struct device *dev,
+ struct of_phandle_args *args)
+{
+ struct platform_device *iommu_pdev = of_find_device_by_node(args->np);
+ struct tegra_mc *mc = platform_get_drvdata(iommu_pdev);
+ u32 id = args->args[0];
+
+ /*
+ * Note: we are here releasing the reference of &iommu_pdev->dev, which
+ * is mc->dev. Although some functions in tegra_smmu_ops may keep using
+ * its private data beyond this point, it's still safe to do so because
+ * the SMMU parent device is the same as the MC, so the reference count
+ * isn't strictly necessary.
+ */
+ put_device(&iommu_pdev->dev);
+
+ dev_iommu_priv_set(dev, mc->smmu);
+
+ return iommu_fwspec_add_ids(dev, &id, 1);
+}
+
+static const struct iommu_ops tegra_smmu_ops = {
+ .domain_alloc = tegra_smmu_domain_alloc,
+ .probe_device = tegra_smmu_probe_device,
+ .device_group = tegra_smmu_device_group,
+ .of_xlate = tegra_smmu_of_xlate,
+ .pgsize_bitmap = SZ_4K,
+ .default_domain_ops = &(const struct iommu_domain_ops) {
+ .attach_dev = tegra_smmu_attach_dev,
+ .detach_dev = tegra_smmu_detach_dev,
+ .map = tegra_smmu_map,
+ .unmap = tegra_smmu_unmap,
+ .iova_to_phys = tegra_smmu_iova_to_phys,
+ .free = tegra_smmu_domain_free,
+ }
+};
+
+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);
+ }
+}
+
+static int tegra_smmu_swgroups_show(struct seq_file *s, void *data)
+{
+ struct tegra_smmu *smmu = s->private;
+ unsigned int i;
+ u32 value;
+
+ seq_printf(s, "swgroup enabled ASID\n");
+ seq_printf(s, "------------------------\n");
+
+ for (i = 0; i < smmu->soc->num_swgroups; i++) {
+ const struct tegra_smmu_swgroup *group = &smmu->soc->swgroups[i];
+ const char *status;
+ unsigned int asid;
+
+ value = smmu_readl(smmu, group->reg);
+
+ if (value & SMMU_ASID_ENABLE)
+ status = "yes";
+ else
+ status = "no";
+
+ asid = value & SMMU_ASID_MASK;
+
+ seq_printf(s, "%-9s %-7s %#04x\n", group->name, status,
+ asid);
+ }
+
+ return 0;
+}
+
+DEFINE_SHOW_ATTRIBUTE(tegra_smmu_swgroups);
+
+static int tegra_smmu_clients_show(struct seq_file *s, void *data)
+{
+ struct tegra_smmu *smmu = s->private;
+ unsigned int i;
+ u32 value;
+
+ seq_printf(s, "client enabled\n");
+ seq_printf(s, "--------------------\n");
+
+ for (i = 0; i < smmu->soc->num_clients; i++) {
+ const struct tegra_mc_client *client = &smmu->soc->clients[i];
+ const char *status;
+
+ value = smmu_readl(smmu, client->regs.smmu.reg);
+
+ if (value & BIT(client->regs.smmu.bit))
+ status = "yes";
+ else
+ status = "no";
+
+ seq_printf(s, "%-12s %s\n", client->name, status);
+ }
+
+ return 0;
+}
+
+DEFINE_SHOW_ATTRIBUTE(tegra_smmu_clients);
+
+static void tegra_smmu_debugfs_init(struct tegra_smmu *smmu)
+{
+ smmu->debugfs = debugfs_create_dir("smmu", NULL);
+ if (!smmu->debugfs)
+ return;
+
+ debugfs_create_file("swgroups", S_IRUGO, smmu->debugfs, smmu,
+ &tegra_smmu_swgroups_fops);
+ debugfs_create_file("clients", S_IRUGO, smmu->debugfs, smmu,
+ &tegra_smmu_clients_fops);
+}
+
+static void tegra_smmu_debugfs_exit(struct tegra_smmu *smmu)
+{
+ debugfs_remove_recursive(smmu->debugfs);
+}
+
+struct tegra_smmu *tegra_smmu_probe(struct device *dev,
+ const struct tegra_smmu_soc *soc,
+ struct tegra_mc *mc)
+{
+ struct tegra_smmu *smmu;
+ u32 value;
+ int err;
+
+ 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 iommu_device_register() will attempt to add
+ * all devices to the IOMMU before we get that far. 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 .probe_device()
+ * callback via the IOMMU device's .drvdata field.
+ */
+ mc->smmu = smmu;
+
+ smmu->asids = devm_bitmap_zalloc(dev, soc->num_asids, GFP_KERNEL);
+ if (!smmu->asids)
+ return ERR_PTR(-ENOMEM);
+
+ INIT_LIST_HEAD(&smmu->groups);
+ 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 - SMMU_PTE_SHIFT) - 1;
+ dev_dbg(dev, "address bits: %u, PFN mask: %#lx\n",
+ mc->soc->num_address_bits, smmu->pfn_mask);
+ smmu->tlb_mask = (1 << fls(smmu->soc->num_tlb_lines)) - 1;
+ dev_dbg(dev, "TLB lines: %u, mask: %#lx\n", smmu->soc->num_tlb_lines,
+ smmu->tlb_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(smmu);
+
+ if (soc->supports_round_robin_arbitration)
+ value |= SMMU_TLB_CONFIG_ROUND_ROBIN_ARBITRATION;
+
+ smmu_writel(smmu, value, SMMU_TLB_CONFIG);
+
+ smmu_flush_ptc_all(smmu);
+ smmu_flush_tlb(smmu);
+ smmu_writel(smmu, SMMU_CONFIG_ENABLE, SMMU_CONFIG);
+ smmu_flush(smmu);
+
+ tegra_smmu_ahb_enable();
+
+ err = iommu_device_sysfs_add(&smmu->iommu, dev, NULL, dev_name(dev));
+ if (err)
+ return ERR_PTR(err);
+
+ err = iommu_device_register(&smmu->iommu, &tegra_smmu_ops, dev);
+ if (err) {
+ iommu_device_sysfs_remove(&smmu->iommu);
+ return ERR_PTR(err);
+ }
+
+ if (IS_ENABLED(CONFIG_DEBUG_FS))
+ tegra_smmu_debugfs_init(smmu);
+
+ return smmu;
+}
+
+void tegra_smmu_remove(struct tegra_smmu *smmu)
+{
+ iommu_device_unregister(&smmu->iommu);
+ iommu_device_sysfs_remove(&smmu->iommu);
+
+ if (IS_ENABLED(CONFIG_DEBUG_FS))
+ tegra_smmu_debugfs_exit(smmu);
+}