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-rw-r--r--drivers/iommu/ipmmu-vmsa.c1166
1 files changed, 1166 insertions, 0 deletions
diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c
new file mode 100644
index 000000000..3b30c0752
--- /dev/null
+++ b/drivers/iommu/ipmmu-vmsa.c
@@ -0,0 +1,1166 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * IOMMU API for Renesas VMSA-compatible IPMMU
+ * Author: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+ *
+ * Copyright (C) 2014-2020 Renesas Electronics Corporation
+ */
+
+#include <linux/bitmap.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/export.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/io-pgtable.h>
+#include <linux/iommu.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/sizes.h>
+#include <linux/slab.h>
+#include <linux/sys_soc.h>
+
+#if defined(CONFIG_ARM) && !defined(CONFIG_IOMMU_DMA)
+#include <asm/dma-iommu.h>
+#else
+#define arm_iommu_create_mapping(...) NULL
+#define arm_iommu_attach_device(...) -ENODEV
+#define arm_iommu_release_mapping(...) do {} while (0)
+#define arm_iommu_detach_device(...) do {} while (0)
+#endif
+
+#define IPMMU_CTX_MAX 16U
+#define IPMMU_CTX_INVALID -1
+
+#define IPMMU_UTLB_MAX 64U
+
+struct ipmmu_features {
+ bool use_ns_alias_offset;
+ bool has_cache_leaf_nodes;
+ unsigned int number_of_contexts;
+ unsigned int num_utlbs;
+ bool setup_imbuscr;
+ bool twobit_imttbcr_sl0;
+ bool reserved_context;
+ bool cache_snoop;
+ unsigned int ctx_offset_base;
+ unsigned int ctx_offset_stride;
+ unsigned int utlb_offset_base;
+};
+
+struct ipmmu_vmsa_device {
+ struct device *dev;
+ void __iomem *base;
+ struct iommu_device iommu;
+ struct ipmmu_vmsa_device *root;
+ const struct ipmmu_features *features;
+ unsigned int num_ctx;
+ spinlock_t lock; /* Protects ctx and domains[] */
+ DECLARE_BITMAP(ctx, IPMMU_CTX_MAX);
+ struct ipmmu_vmsa_domain *domains[IPMMU_CTX_MAX];
+ s8 utlb_ctx[IPMMU_UTLB_MAX];
+
+ struct iommu_group *group;
+ struct dma_iommu_mapping *mapping;
+};
+
+struct ipmmu_vmsa_domain {
+ struct ipmmu_vmsa_device *mmu;
+ struct iommu_domain io_domain;
+
+ struct io_pgtable_cfg cfg;
+ struct io_pgtable_ops *iop;
+
+ unsigned int context_id;
+ struct mutex mutex; /* Protects mappings */
+};
+
+static struct ipmmu_vmsa_domain *to_vmsa_domain(struct iommu_domain *dom)
+{
+ return container_of(dom, struct ipmmu_vmsa_domain, io_domain);
+}
+
+static struct ipmmu_vmsa_device *to_ipmmu(struct device *dev)
+{
+ return dev_iommu_priv_get(dev);
+}
+
+#define TLB_LOOP_TIMEOUT 100 /* 100us */
+
+/* -----------------------------------------------------------------------------
+ * Registers Definition
+ */
+
+#define IM_NS_ALIAS_OFFSET 0x800
+
+/* MMU "context" registers */
+#define IMCTR 0x0000 /* R-Car Gen2/3 */
+#define IMCTR_INTEN (1 << 2) /* R-Car Gen2/3 */
+#define IMCTR_FLUSH (1 << 1) /* R-Car Gen2/3 */
+#define IMCTR_MMUEN (1 << 0) /* R-Car Gen2/3 */
+
+#define IMTTBCR 0x0008 /* R-Car Gen2/3 */
+#define IMTTBCR_EAE (1 << 31) /* R-Car Gen2/3 */
+#define IMTTBCR_SH0_INNER_SHAREABLE (3 << 12) /* R-Car Gen2 only */
+#define IMTTBCR_ORGN0_WB_WA (1 << 10) /* R-Car Gen2 only */
+#define IMTTBCR_IRGN0_WB_WA (1 << 8) /* R-Car Gen2 only */
+#define IMTTBCR_SL0_TWOBIT_LVL_1 (2 << 6) /* R-Car Gen3 only */
+#define IMTTBCR_SL0_LVL_1 (1 << 4) /* R-Car Gen2 only */
+
+#define IMBUSCR 0x000c /* R-Car Gen2 only */
+#define IMBUSCR_DVM (1 << 2) /* R-Car Gen2 only */
+#define IMBUSCR_BUSSEL_MASK (3 << 0) /* R-Car Gen2 only */
+
+#define IMTTLBR0 0x0010 /* R-Car Gen2/3 */
+#define IMTTUBR0 0x0014 /* R-Car Gen2/3 */
+
+#define IMSTR 0x0020 /* R-Car Gen2/3 */
+#define IMSTR_MHIT (1 << 4) /* R-Car Gen2/3 */
+#define IMSTR_ABORT (1 << 2) /* R-Car Gen2/3 */
+#define IMSTR_PF (1 << 1) /* R-Car Gen2/3 */
+#define IMSTR_TF (1 << 0) /* R-Car Gen2/3 */
+
+#define IMMAIR0 0x0028 /* R-Car Gen2/3 */
+
+#define IMELAR 0x0030 /* R-Car Gen2/3, IMEAR on R-Car Gen2 */
+#define IMEUAR 0x0034 /* R-Car Gen3 only */
+
+/* uTLB registers */
+#define IMUCTR(n) ((n) < 32 ? IMUCTR0(n) : IMUCTR32(n))
+#define IMUCTR0(n) (0x0300 + ((n) * 16)) /* R-Car Gen2/3 */
+#define IMUCTR32(n) (0x0600 + (((n) - 32) * 16)) /* R-Car Gen3 only */
+#define IMUCTR_TTSEL_MMU(n) ((n) << 4) /* R-Car Gen2/3 */
+#define IMUCTR_FLUSH (1 << 1) /* R-Car Gen2/3 */
+#define IMUCTR_MMUEN (1 << 0) /* R-Car Gen2/3 */
+
+#define IMUASID(n) ((n) < 32 ? IMUASID0(n) : IMUASID32(n))
+#define IMUASID0(n) (0x0308 + ((n) * 16)) /* R-Car Gen2/3 */
+#define IMUASID32(n) (0x0608 + (((n) - 32) * 16)) /* R-Car Gen3 only */
+
+/* -----------------------------------------------------------------------------
+ * Root device handling
+ */
+
+static struct platform_driver ipmmu_driver;
+
+static bool ipmmu_is_root(struct ipmmu_vmsa_device *mmu)
+{
+ return mmu->root == mmu;
+}
+
+static int __ipmmu_check_device(struct device *dev, void *data)
+{
+ struct ipmmu_vmsa_device *mmu = dev_get_drvdata(dev);
+ struct ipmmu_vmsa_device **rootp = data;
+
+ if (ipmmu_is_root(mmu))
+ *rootp = mmu;
+
+ return 0;
+}
+
+static struct ipmmu_vmsa_device *ipmmu_find_root(void)
+{
+ struct ipmmu_vmsa_device *root = NULL;
+
+ return driver_for_each_device(&ipmmu_driver.driver, NULL, &root,
+ __ipmmu_check_device) == 0 ? root : NULL;
+}
+
+/* -----------------------------------------------------------------------------
+ * Read/Write Access
+ */
+
+static u32 ipmmu_read(struct ipmmu_vmsa_device *mmu, unsigned int offset)
+{
+ return ioread32(mmu->base + offset);
+}
+
+static void ipmmu_write(struct ipmmu_vmsa_device *mmu, unsigned int offset,
+ u32 data)
+{
+ iowrite32(data, mmu->base + offset);
+}
+
+static unsigned int ipmmu_ctx_reg(struct ipmmu_vmsa_device *mmu,
+ unsigned int context_id, unsigned int reg)
+{
+ unsigned int base = mmu->features->ctx_offset_base;
+
+ if (context_id > 7)
+ base += 0x800 - 8 * 0x40;
+
+ return base + context_id * mmu->features->ctx_offset_stride + reg;
+}
+
+static u32 ipmmu_ctx_read(struct ipmmu_vmsa_device *mmu,
+ unsigned int context_id, unsigned int reg)
+{
+ return ipmmu_read(mmu, ipmmu_ctx_reg(mmu, context_id, reg));
+}
+
+static void ipmmu_ctx_write(struct ipmmu_vmsa_device *mmu,
+ unsigned int context_id, unsigned int reg, u32 data)
+{
+ ipmmu_write(mmu, ipmmu_ctx_reg(mmu, context_id, reg), data);
+}
+
+static u32 ipmmu_ctx_read_root(struct ipmmu_vmsa_domain *domain,
+ unsigned int reg)
+{
+ return ipmmu_ctx_read(domain->mmu->root, domain->context_id, reg);
+}
+
+static void ipmmu_ctx_write_root(struct ipmmu_vmsa_domain *domain,
+ unsigned int reg, u32 data)
+{
+ ipmmu_ctx_write(domain->mmu->root, domain->context_id, reg, data);
+}
+
+static void ipmmu_ctx_write_all(struct ipmmu_vmsa_domain *domain,
+ unsigned int reg, u32 data)
+{
+ if (domain->mmu != domain->mmu->root)
+ ipmmu_ctx_write(domain->mmu, domain->context_id, reg, data);
+
+ ipmmu_ctx_write(domain->mmu->root, domain->context_id, reg, data);
+}
+
+static u32 ipmmu_utlb_reg(struct ipmmu_vmsa_device *mmu, unsigned int reg)
+{
+ return mmu->features->utlb_offset_base + reg;
+}
+
+static void ipmmu_imuasid_write(struct ipmmu_vmsa_device *mmu,
+ unsigned int utlb, u32 data)
+{
+ ipmmu_write(mmu, ipmmu_utlb_reg(mmu, IMUASID(utlb)), data);
+}
+
+static void ipmmu_imuctr_write(struct ipmmu_vmsa_device *mmu,
+ unsigned int utlb, u32 data)
+{
+ ipmmu_write(mmu, ipmmu_utlb_reg(mmu, IMUCTR(utlb)), data);
+}
+
+/* -----------------------------------------------------------------------------
+ * TLB and microTLB Management
+ */
+
+/* Wait for any pending TLB invalidations to complete */
+static void ipmmu_tlb_sync(struct ipmmu_vmsa_domain *domain)
+{
+ unsigned int count = 0;
+
+ while (ipmmu_ctx_read_root(domain, IMCTR) & IMCTR_FLUSH) {
+ cpu_relax();
+ if (++count == TLB_LOOP_TIMEOUT) {
+ dev_err_ratelimited(domain->mmu->dev,
+ "TLB sync timed out -- MMU may be deadlocked\n");
+ return;
+ }
+ udelay(1);
+ }
+}
+
+static void ipmmu_tlb_invalidate(struct ipmmu_vmsa_domain *domain)
+{
+ u32 reg;
+
+ reg = ipmmu_ctx_read_root(domain, IMCTR);
+ reg |= IMCTR_FLUSH;
+ ipmmu_ctx_write_all(domain, IMCTR, reg);
+
+ ipmmu_tlb_sync(domain);
+}
+
+/*
+ * Enable MMU translation for the microTLB.
+ */
+static void ipmmu_utlb_enable(struct ipmmu_vmsa_domain *domain,
+ unsigned int utlb)
+{
+ struct ipmmu_vmsa_device *mmu = domain->mmu;
+
+ /*
+ * TODO: Reference-count the microTLB as several bus masters can be
+ * connected to the same microTLB.
+ */
+
+ /* TODO: What should we set the ASID to ? */
+ ipmmu_imuasid_write(mmu, utlb, 0);
+ /* TODO: Do we need to flush the microTLB ? */
+ ipmmu_imuctr_write(mmu, utlb, IMUCTR_TTSEL_MMU(domain->context_id) |
+ IMUCTR_FLUSH | IMUCTR_MMUEN);
+ mmu->utlb_ctx[utlb] = domain->context_id;
+}
+
+/*
+ * Disable MMU translation for the microTLB.
+ */
+static void ipmmu_utlb_disable(struct ipmmu_vmsa_domain *domain,
+ unsigned int utlb)
+{
+ struct ipmmu_vmsa_device *mmu = domain->mmu;
+
+ ipmmu_imuctr_write(mmu, utlb, 0);
+ mmu->utlb_ctx[utlb] = IPMMU_CTX_INVALID;
+}
+
+static void ipmmu_tlb_flush_all(void *cookie)
+{
+ struct ipmmu_vmsa_domain *domain = cookie;
+
+ ipmmu_tlb_invalidate(domain);
+}
+
+static void ipmmu_tlb_flush(unsigned long iova, size_t size,
+ size_t granule, void *cookie)
+{
+ ipmmu_tlb_flush_all(cookie);
+}
+
+static const struct iommu_flush_ops ipmmu_flush_ops = {
+ .tlb_flush_all = ipmmu_tlb_flush_all,
+ .tlb_flush_walk = ipmmu_tlb_flush,
+};
+
+/* -----------------------------------------------------------------------------
+ * Domain/Context Management
+ */
+
+static int ipmmu_domain_allocate_context(struct ipmmu_vmsa_device *mmu,
+ struct ipmmu_vmsa_domain *domain)
+{
+ unsigned long flags;
+ int ret;
+
+ spin_lock_irqsave(&mmu->lock, flags);
+
+ ret = find_first_zero_bit(mmu->ctx, mmu->num_ctx);
+ if (ret != mmu->num_ctx) {
+ mmu->domains[ret] = domain;
+ set_bit(ret, mmu->ctx);
+ } else
+ ret = -EBUSY;
+
+ spin_unlock_irqrestore(&mmu->lock, flags);
+
+ return ret;
+}
+
+static void ipmmu_domain_free_context(struct ipmmu_vmsa_device *mmu,
+ unsigned int context_id)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&mmu->lock, flags);
+
+ clear_bit(context_id, mmu->ctx);
+ mmu->domains[context_id] = NULL;
+
+ spin_unlock_irqrestore(&mmu->lock, flags);
+}
+
+static void ipmmu_domain_setup_context(struct ipmmu_vmsa_domain *domain)
+{
+ u64 ttbr;
+ u32 tmp;
+
+ /* TTBR0 */
+ ttbr = domain->cfg.arm_lpae_s1_cfg.ttbr;
+ ipmmu_ctx_write_root(domain, IMTTLBR0, ttbr);
+ ipmmu_ctx_write_root(domain, IMTTUBR0, ttbr >> 32);
+
+ /*
+ * TTBCR
+ * We use long descriptors and allocate the whole 32-bit VA space to
+ * TTBR0.
+ */
+ if (domain->mmu->features->twobit_imttbcr_sl0)
+ tmp = IMTTBCR_SL0_TWOBIT_LVL_1;
+ else
+ tmp = IMTTBCR_SL0_LVL_1;
+
+ if (domain->mmu->features->cache_snoop)
+ tmp |= IMTTBCR_SH0_INNER_SHAREABLE | IMTTBCR_ORGN0_WB_WA |
+ IMTTBCR_IRGN0_WB_WA;
+
+ ipmmu_ctx_write_root(domain, IMTTBCR, IMTTBCR_EAE | tmp);
+
+ /* MAIR0 */
+ ipmmu_ctx_write_root(domain, IMMAIR0,
+ domain->cfg.arm_lpae_s1_cfg.mair);
+
+ /* IMBUSCR */
+ if (domain->mmu->features->setup_imbuscr)
+ ipmmu_ctx_write_root(domain, IMBUSCR,
+ ipmmu_ctx_read_root(domain, IMBUSCR) &
+ ~(IMBUSCR_DVM | IMBUSCR_BUSSEL_MASK));
+
+ /*
+ * IMSTR
+ * Clear all interrupt flags.
+ */
+ ipmmu_ctx_write_root(domain, IMSTR, ipmmu_ctx_read_root(domain, IMSTR));
+
+ /*
+ * IMCTR
+ * Enable the MMU and interrupt generation. The long-descriptor
+ * translation table format doesn't use TEX remapping. Don't enable AF
+ * software management as we have no use for it. Flush the TLB as
+ * required when modifying the context registers.
+ */
+ ipmmu_ctx_write_all(domain, IMCTR,
+ IMCTR_INTEN | IMCTR_FLUSH | IMCTR_MMUEN);
+}
+
+static int ipmmu_domain_init_context(struct ipmmu_vmsa_domain *domain)
+{
+ int ret;
+
+ /*
+ * Allocate the page table operations.
+ *
+ * VMSA states in section B3.6.3 "Control of Secure or Non-secure memory
+ * access, Long-descriptor format" that the NStable bit being set in a
+ * table descriptor will result in the NStable and NS bits of all child
+ * entries being ignored and considered as being set. The IPMMU seems
+ * not to comply with this, as it generates a secure access page fault
+ * if any of the NStable and NS bits isn't set when running in
+ * non-secure mode.
+ */
+ domain->cfg.quirks = IO_PGTABLE_QUIRK_ARM_NS;
+ domain->cfg.pgsize_bitmap = SZ_1G | SZ_2M | SZ_4K;
+ domain->cfg.ias = 32;
+ domain->cfg.oas = 40;
+ domain->cfg.tlb = &ipmmu_flush_ops;
+ domain->io_domain.geometry.aperture_end = DMA_BIT_MASK(32);
+ domain->io_domain.geometry.force_aperture = true;
+ /*
+ * TODO: Add support for coherent walk through CCI with DVM and remove
+ * cache handling. For now, delegate it to the io-pgtable code.
+ */
+ domain->cfg.coherent_walk = false;
+ domain->cfg.iommu_dev = domain->mmu->root->dev;
+
+ /*
+ * Find an unused context.
+ */
+ ret = ipmmu_domain_allocate_context(domain->mmu->root, domain);
+ if (ret < 0)
+ return ret;
+
+ domain->context_id = ret;
+
+ domain->iop = alloc_io_pgtable_ops(ARM_32_LPAE_S1, &domain->cfg,
+ domain);
+ if (!domain->iop) {
+ ipmmu_domain_free_context(domain->mmu->root,
+ domain->context_id);
+ return -EINVAL;
+ }
+
+ ipmmu_domain_setup_context(domain);
+ return 0;
+}
+
+static void ipmmu_domain_destroy_context(struct ipmmu_vmsa_domain *domain)
+{
+ if (!domain->mmu)
+ return;
+
+ /*
+ * Disable the context. Flush the TLB as required when modifying the
+ * context registers.
+ *
+ * TODO: Is TLB flush really needed ?
+ */
+ ipmmu_ctx_write_all(domain, IMCTR, IMCTR_FLUSH);
+ ipmmu_tlb_sync(domain);
+ ipmmu_domain_free_context(domain->mmu->root, domain->context_id);
+}
+
+/* -----------------------------------------------------------------------------
+ * Fault Handling
+ */
+
+static irqreturn_t ipmmu_domain_irq(struct ipmmu_vmsa_domain *domain)
+{
+ const u32 err_mask = IMSTR_MHIT | IMSTR_ABORT | IMSTR_PF | IMSTR_TF;
+ struct ipmmu_vmsa_device *mmu = domain->mmu;
+ unsigned long iova;
+ u32 status;
+
+ status = ipmmu_ctx_read_root(domain, IMSTR);
+ if (!(status & err_mask))
+ return IRQ_NONE;
+
+ iova = ipmmu_ctx_read_root(domain, IMELAR);
+ if (IS_ENABLED(CONFIG_64BIT))
+ iova |= (u64)ipmmu_ctx_read_root(domain, IMEUAR) << 32;
+
+ /*
+ * Clear the error status flags. Unlike traditional interrupt flag
+ * registers that must be cleared by writing 1, this status register
+ * seems to require 0. The error address register must be read before,
+ * otherwise its value will be 0.
+ */
+ ipmmu_ctx_write_root(domain, IMSTR, 0);
+
+ /* Log fatal errors. */
+ if (status & IMSTR_MHIT)
+ dev_err_ratelimited(mmu->dev, "Multiple TLB hits @0x%lx\n",
+ iova);
+ if (status & IMSTR_ABORT)
+ dev_err_ratelimited(mmu->dev, "Page Table Walk Abort @0x%lx\n",
+ iova);
+
+ if (!(status & (IMSTR_PF | IMSTR_TF)))
+ return IRQ_NONE;
+
+ /*
+ * Try to handle page faults and translation faults.
+ *
+ * TODO: We need to look up the faulty device based on the I/O VA. Use
+ * the IOMMU device for now.
+ */
+ if (!report_iommu_fault(&domain->io_domain, mmu->dev, iova, 0))
+ return IRQ_HANDLED;
+
+ dev_err_ratelimited(mmu->dev,
+ "Unhandled fault: status 0x%08x iova 0x%lx\n",
+ status, iova);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t ipmmu_irq(int irq, void *dev)
+{
+ struct ipmmu_vmsa_device *mmu = dev;
+ irqreturn_t status = IRQ_NONE;
+ unsigned int i;
+ unsigned long flags;
+
+ spin_lock_irqsave(&mmu->lock, flags);
+
+ /*
+ * Check interrupts for all active contexts.
+ */
+ for (i = 0; i < mmu->num_ctx; i++) {
+ if (!mmu->domains[i])
+ continue;
+ if (ipmmu_domain_irq(mmu->domains[i]) == IRQ_HANDLED)
+ status = IRQ_HANDLED;
+ }
+
+ spin_unlock_irqrestore(&mmu->lock, flags);
+
+ return status;
+}
+
+/* -----------------------------------------------------------------------------
+ * IOMMU Operations
+ */
+
+static struct iommu_domain *ipmmu_domain_alloc(unsigned type)
+{
+ struct ipmmu_vmsa_domain *domain;
+
+ if (type != IOMMU_DOMAIN_UNMANAGED && type != IOMMU_DOMAIN_DMA)
+ return NULL;
+
+ domain = kzalloc(sizeof(*domain), GFP_KERNEL);
+ if (!domain)
+ return NULL;
+
+ mutex_init(&domain->mutex);
+
+ return &domain->io_domain;
+}
+
+static void ipmmu_domain_free(struct iommu_domain *io_domain)
+{
+ struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
+
+ /*
+ * Free the domain resources. We assume that all devices have already
+ * been detached.
+ */
+ ipmmu_domain_destroy_context(domain);
+ free_io_pgtable_ops(domain->iop);
+ kfree(domain);
+}
+
+static int ipmmu_attach_device(struct iommu_domain *io_domain,
+ struct device *dev)
+{
+ struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
+ struct ipmmu_vmsa_device *mmu = to_ipmmu(dev);
+ struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
+ unsigned int i;
+ int ret = 0;
+
+ if (!mmu) {
+ dev_err(dev, "Cannot attach to IPMMU\n");
+ return -ENXIO;
+ }
+
+ mutex_lock(&domain->mutex);
+
+ if (!domain->mmu) {
+ /* The domain hasn't been used yet, initialize it. */
+ domain->mmu = mmu;
+ ret = ipmmu_domain_init_context(domain);
+ if (ret < 0) {
+ dev_err(dev, "Unable to initialize IPMMU context\n");
+ domain->mmu = NULL;
+ } else {
+ dev_info(dev, "Using IPMMU context %u\n",
+ domain->context_id);
+ }
+ } else if (domain->mmu != mmu) {
+ /*
+ * Something is wrong, we can't attach two devices using
+ * different IOMMUs to the same domain.
+ */
+ dev_err(dev, "Can't attach IPMMU %s to domain on IPMMU %s\n",
+ dev_name(mmu->dev), dev_name(domain->mmu->dev));
+ ret = -EINVAL;
+ } else
+ dev_info(dev, "Reusing IPMMU context %u\n", domain->context_id);
+
+ mutex_unlock(&domain->mutex);
+
+ if (ret < 0)
+ return ret;
+
+ for (i = 0; i < fwspec->num_ids; ++i)
+ ipmmu_utlb_enable(domain, fwspec->ids[i]);
+
+ return 0;
+}
+
+static void ipmmu_detach_device(struct iommu_domain *io_domain,
+ struct device *dev)
+{
+ struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
+ struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
+ unsigned int i;
+
+ for (i = 0; i < fwspec->num_ids; ++i)
+ ipmmu_utlb_disable(domain, fwspec->ids[i]);
+
+ /*
+ * TODO: Optimize by disabling the context when no device is attached.
+ */
+}
+
+static int ipmmu_map(struct iommu_domain *io_domain, unsigned long iova,
+ phys_addr_t paddr, size_t size, int prot, gfp_t gfp)
+{
+ struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
+
+ if (!domain)
+ return -ENODEV;
+
+ return domain->iop->map(domain->iop, iova, paddr, size, prot, gfp);
+}
+
+static size_t ipmmu_unmap(struct iommu_domain *io_domain, unsigned long iova,
+ size_t size, struct iommu_iotlb_gather *gather)
+{
+ struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
+
+ return domain->iop->unmap(domain->iop, iova, size, gather);
+}
+
+static void ipmmu_flush_iotlb_all(struct iommu_domain *io_domain)
+{
+ struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
+
+ if (domain->mmu)
+ ipmmu_tlb_flush_all(domain);
+}
+
+static void ipmmu_iotlb_sync(struct iommu_domain *io_domain,
+ struct iommu_iotlb_gather *gather)
+{
+ ipmmu_flush_iotlb_all(io_domain);
+}
+
+static phys_addr_t ipmmu_iova_to_phys(struct iommu_domain *io_domain,
+ dma_addr_t iova)
+{
+ struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
+
+ /* TODO: Is locking needed ? */
+
+ return domain->iop->iova_to_phys(domain->iop, iova);
+}
+
+static int ipmmu_init_platform_device(struct device *dev,
+ struct of_phandle_args *args)
+{
+ struct platform_device *ipmmu_pdev;
+
+ ipmmu_pdev = of_find_device_by_node(args->np);
+ if (!ipmmu_pdev)
+ return -ENODEV;
+
+ dev_iommu_priv_set(dev, platform_get_drvdata(ipmmu_pdev));
+
+ return 0;
+}
+
+static const struct soc_device_attribute soc_needs_opt_in[] = {
+ { .family = "R-Car Gen3", },
+ { .family = "R-Car Gen4", },
+ { .family = "RZ/G2", },
+ { /* sentinel */ }
+};
+
+static const struct soc_device_attribute soc_denylist[] = {
+ { .soc_id = "r8a774a1", },
+ { .soc_id = "r8a7795", .revision = "ES1.*" },
+ { .soc_id = "r8a7795", .revision = "ES2.*" },
+ { .soc_id = "r8a7796", },
+ { /* sentinel */ }
+};
+
+static const char * const devices_allowlist[] = {
+ "ee100000.mmc",
+ "ee120000.mmc",
+ "ee140000.mmc",
+ "ee160000.mmc"
+};
+
+static bool ipmmu_device_is_allowed(struct device *dev)
+{
+ unsigned int i;
+
+ /*
+ * R-Car Gen3/4 and RZ/G2 use the allow list to opt-in devices.
+ * For Other SoCs, this returns true anyway.
+ */
+ if (!soc_device_match(soc_needs_opt_in))
+ return true;
+
+ /* Check whether this SoC can use the IPMMU correctly or not */
+ if (soc_device_match(soc_denylist))
+ return false;
+
+ /* Check whether this device can work with the IPMMU */
+ for (i = 0; i < ARRAY_SIZE(devices_allowlist); i++) {
+ if (!strcmp(dev_name(dev), devices_allowlist[i]))
+ return true;
+ }
+
+ /* Otherwise, do not allow use of IPMMU */
+ return false;
+}
+
+static int ipmmu_of_xlate(struct device *dev,
+ struct of_phandle_args *spec)
+{
+ if (!ipmmu_device_is_allowed(dev))
+ return -ENODEV;
+
+ iommu_fwspec_add_ids(dev, spec->args, 1);
+
+ /* Initialize once - xlate() will call multiple times */
+ if (to_ipmmu(dev))
+ return 0;
+
+ return ipmmu_init_platform_device(dev, spec);
+}
+
+static int ipmmu_init_arm_mapping(struct device *dev)
+{
+ struct ipmmu_vmsa_device *mmu = to_ipmmu(dev);
+ int ret;
+
+ /*
+ * Create the ARM mapping, used by the ARM DMA mapping core to allocate
+ * VAs. This will allocate a corresponding IOMMU domain.
+ *
+ * TODO:
+ * - Create one mapping per context (TLB).
+ * - Make the mapping size configurable ? We currently use a 2GB mapping
+ * at a 1GB offset to ensure that NULL VAs will fault.
+ */
+ if (!mmu->mapping) {
+ struct dma_iommu_mapping *mapping;
+
+ mapping = arm_iommu_create_mapping(&platform_bus_type,
+ SZ_1G, SZ_2G);
+ if (IS_ERR(mapping)) {
+ dev_err(mmu->dev, "failed to create ARM IOMMU mapping\n");
+ ret = PTR_ERR(mapping);
+ goto error;
+ }
+
+ mmu->mapping = mapping;
+ }
+
+ /* Attach the ARM VA mapping to the device. */
+ ret = arm_iommu_attach_device(dev, mmu->mapping);
+ if (ret < 0) {
+ dev_err(dev, "Failed to attach device to VA mapping\n");
+ goto error;
+ }
+
+ return 0;
+
+error:
+ if (mmu->mapping)
+ arm_iommu_release_mapping(mmu->mapping);
+
+ return ret;
+}
+
+static struct iommu_device *ipmmu_probe_device(struct device *dev)
+{
+ struct ipmmu_vmsa_device *mmu = to_ipmmu(dev);
+
+ /*
+ * Only let through devices that have been verified in xlate()
+ */
+ if (!mmu)
+ return ERR_PTR(-ENODEV);
+
+ return &mmu->iommu;
+}
+
+static void ipmmu_probe_finalize(struct device *dev)
+{
+ int ret = 0;
+
+ if (IS_ENABLED(CONFIG_ARM) && !IS_ENABLED(CONFIG_IOMMU_DMA))
+ ret = ipmmu_init_arm_mapping(dev);
+
+ if (ret)
+ dev_err(dev, "Can't create IOMMU mapping - DMA-OPS will not work\n");
+}
+
+static void ipmmu_release_device(struct device *dev)
+{
+ arm_iommu_detach_device(dev);
+}
+
+static struct iommu_group *ipmmu_find_group(struct device *dev)
+{
+ struct ipmmu_vmsa_device *mmu = to_ipmmu(dev);
+ struct iommu_group *group;
+
+ if (mmu->group)
+ return iommu_group_ref_get(mmu->group);
+
+ group = iommu_group_alloc();
+ if (!IS_ERR(group))
+ mmu->group = group;
+
+ return group;
+}
+
+static const struct iommu_ops ipmmu_ops = {
+ .domain_alloc = ipmmu_domain_alloc,
+ .probe_device = ipmmu_probe_device,
+ .release_device = ipmmu_release_device,
+ .probe_finalize = ipmmu_probe_finalize,
+ .device_group = IS_ENABLED(CONFIG_ARM) && !IS_ENABLED(CONFIG_IOMMU_DMA)
+ ? generic_device_group : ipmmu_find_group,
+ .pgsize_bitmap = SZ_1G | SZ_2M | SZ_4K,
+ .of_xlate = ipmmu_of_xlate,
+ .default_domain_ops = &(const struct iommu_domain_ops) {
+ .attach_dev = ipmmu_attach_device,
+ .detach_dev = ipmmu_detach_device,
+ .map = ipmmu_map,
+ .unmap = ipmmu_unmap,
+ .flush_iotlb_all = ipmmu_flush_iotlb_all,
+ .iotlb_sync = ipmmu_iotlb_sync,
+ .iova_to_phys = ipmmu_iova_to_phys,
+ .free = ipmmu_domain_free,
+ }
+};
+
+/* -----------------------------------------------------------------------------
+ * Probe/remove and init
+ */
+
+static void ipmmu_device_reset(struct ipmmu_vmsa_device *mmu)
+{
+ unsigned int i;
+
+ /* Disable all contexts. */
+ for (i = 0; i < mmu->num_ctx; ++i)
+ ipmmu_ctx_write(mmu, i, IMCTR, 0);
+}
+
+static const struct ipmmu_features ipmmu_features_default = {
+ .use_ns_alias_offset = true,
+ .has_cache_leaf_nodes = false,
+ .number_of_contexts = 1, /* software only tested with one context */
+ .num_utlbs = 32,
+ .setup_imbuscr = true,
+ .twobit_imttbcr_sl0 = false,
+ .reserved_context = false,
+ .cache_snoop = true,
+ .ctx_offset_base = 0,
+ .ctx_offset_stride = 0x40,
+ .utlb_offset_base = 0,
+};
+
+static const struct ipmmu_features ipmmu_features_rcar_gen3 = {
+ .use_ns_alias_offset = false,
+ .has_cache_leaf_nodes = true,
+ .number_of_contexts = 8,
+ .num_utlbs = 48,
+ .setup_imbuscr = false,
+ .twobit_imttbcr_sl0 = true,
+ .reserved_context = true,
+ .cache_snoop = false,
+ .ctx_offset_base = 0,
+ .ctx_offset_stride = 0x40,
+ .utlb_offset_base = 0,
+};
+
+static const struct ipmmu_features ipmmu_features_rcar_gen4 = {
+ .use_ns_alias_offset = false,
+ .has_cache_leaf_nodes = true,
+ .number_of_contexts = 16,
+ .num_utlbs = 64,
+ .setup_imbuscr = false,
+ .twobit_imttbcr_sl0 = true,
+ .reserved_context = true,
+ .cache_snoop = false,
+ .ctx_offset_base = 0x10000,
+ .ctx_offset_stride = 0x1040,
+ .utlb_offset_base = 0x3000,
+};
+
+static const struct of_device_id ipmmu_of_ids[] = {
+ {
+ .compatible = "renesas,ipmmu-vmsa",
+ .data = &ipmmu_features_default,
+ }, {
+ .compatible = "renesas,ipmmu-r8a774a1",
+ .data = &ipmmu_features_rcar_gen3,
+ }, {
+ .compatible = "renesas,ipmmu-r8a774b1",
+ .data = &ipmmu_features_rcar_gen3,
+ }, {
+ .compatible = "renesas,ipmmu-r8a774c0",
+ .data = &ipmmu_features_rcar_gen3,
+ }, {
+ .compatible = "renesas,ipmmu-r8a774e1",
+ .data = &ipmmu_features_rcar_gen3,
+ }, {
+ .compatible = "renesas,ipmmu-r8a7795",
+ .data = &ipmmu_features_rcar_gen3,
+ }, {
+ .compatible = "renesas,ipmmu-r8a7796",
+ .data = &ipmmu_features_rcar_gen3,
+ }, {
+ .compatible = "renesas,ipmmu-r8a77961",
+ .data = &ipmmu_features_rcar_gen3,
+ }, {
+ .compatible = "renesas,ipmmu-r8a77965",
+ .data = &ipmmu_features_rcar_gen3,
+ }, {
+ .compatible = "renesas,ipmmu-r8a77970",
+ .data = &ipmmu_features_rcar_gen3,
+ }, {
+ .compatible = "renesas,ipmmu-r8a77980",
+ .data = &ipmmu_features_rcar_gen3,
+ }, {
+ .compatible = "renesas,ipmmu-r8a77990",
+ .data = &ipmmu_features_rcar_gen3,
+ }, {
+ .compatible = "renesas,ipmmu-r8a77995",
+ .data = &ipmmu_features_rcar_gen3,
+ }, {
+ .compatible = "renesas,ipmmu-r8a779a0",
+ .data = &ipmmu_features_rcar_gen4,
+ }, {
+ .compatible = "renesas,rcar-gen4-ipmmu-vmsa",
+ .data = &ipmmu_features_rcar_gen4,
+ }, {
+ /* Terminator */
+ },
+};
+
+static int ipmmu_probe(struct platform_device *pdev)
+{
+ struct ipmmu_vmsa_device *mmu;
+ struct resource *res;
+ int irq;
+ int ret;
+
+ mmu = devm_kzalloc(&pdev->dev, sizeof(*mmu), GFP_KERNEL);
+ if (!mmu) {
+ dev_err(&pdev->dev, "cannot allocate device data\n");
+ return -ENOMEM;
+ }
+
+ mmu->dev = &pdev->dev;
+ spin_lock_init(&mmu->lock);
+ bitmap_zero(mmu->ctx, IPMMU_CTX_MAX);
+ mmu->features = of_device_get_match_data(&pdev->dev);
+ memset(mmu->utlb_ctx, IPMMU_CTX_INVALID, mmu->features->num_utlbs);
+ ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(40));
+ if (ret)
+ return ret;
+
+ /* Map I/O memory and request IRQ. */
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ mmu->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(mmu->base))
+ return PTR_ERR(mmu->base);
+
+ /*
+ * The IPMMU has two register banks, for secure and non-secure modes.
+ * The bank mapped at the beginning of the IPMMU address space
+ * corresponds to the running mode of the CPU. When running in secure
+ * mode the non-secure register bank is also available at an offset.
+ *
+ * Secure mode operation isn't clearly documented and is thus currently
+ * not implemented in the driver. Furthermore, preliminary tests of
+ * non-secure operation with the main register bank were not successful.
+ * Offset the registers base unconditionally to point to the non-secure
+ * alias space for now.
+ */
+ if (mmu->features->use_ns_alias_offset)
+ mmu->base += IM_NS_ALIAS_OFFSET;
+
+ mmu->num_ctx = min(IPMMU_CTX_MAX, mmu->features->number_of_contexts);
+
+ /*
+ * Determine if this IPMMU instance is a root device by checking for
+ * the lack of has_cache_leaf_nodes flag or renesas,ipmmu-main property.
+ */
+ if (!mmu->features->has_cache_leaf_nodes ||
+ !of_find_property(pdev->dev.of_node, "renesas,ipmmu-main", NULL))
+ mmu->root = mmu;
+ else
+ mmu->root = ipmmu_find_root();
+
+ /*
+ * Wait until the root device has been registered for sure.
+ */
+ if (!mmu->root)
+ return -EPROBE_DEFER;
+
+ /* Root devices have mandatory IRQs */
+ if (ipmmu_is_root(mmu)) {
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return irq;
+
+ ret = devm_request_irq(&pdev->dev, irq, ipmmu_irq, 0,
+ dev_name(&pdev->dev), mmu);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to request IRQ %d\n", irq);
+ return ret;
+ }
+
+ ipmmu_device_reset(mmu);
+
+ if (mmu->features->reserved_context) {
+ dev_info(&pdev->dev, "IPMMU context 0 is reserved\n");
+ set_bit(0, mmu->ctx);
+ }
+ }
+
+ /*
+ * Register the IPMMU to the IOMMU subsystem in the following cases:
+ * - R-Car Gen2 IPMMU (all devices registered)
+ * - R-Car Gen3 IPMMU (leaf devices only - skip root IPMMU-MM device)
+ */
+ if (!mmu->features->has_cache_leaf_nodes || !ipmmu_is_root(mmu)) {
+ ret = iommu_device_sysfs_add(&mmu->iommu, &pdev->dev, NULL,
+ dev_name(&pdev->dev));
+ if (ret)
+ return ret;
+
+ ret = iommu_device_register(&mmu->iommu, &ipmmu_ops, &pdev->dev);
+ if (ret)
+ return ret;
+ }
+
+ /*
+ * We can't create the ARM mapping here as it requires the bus to have
+ * an IOMMU, which only happens when bus_set_iommu() is called in
+ * ipmmu_init() after the probe function returns.
+ */
+
+ platform_set_drvdata(pdev, mmu);
+
+ return 0;
+}
+
+static int ipmmu_remove(struct platform_device *pdev)
+{
+ struct ipmmu_vmsa_device *mmu = platform_get_drvdata(pdev);
+
+ iommu_device_sysfs_remove(&mmu->iommu);
+ iommu_device_unregister(&mmu->iommu);
+
+ arm_iommu_release_mapping(mmu->mapping);
+
+ ipmmu_device_reset(mmu);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int ipmmu_resume_noirq(struct device *dev)
+{
+ struct ipmmu_vmsa_device *mmu = dev_get_drvdata(dev);
+ unsigned int i;
+
+ /* Reset root MMU and restore contexts */
+ if (ipmmu_is_root(mmu)) {
+ ipmmu_device_reset(mmu);
+
+ for (i = 0; i < mmu->num_ctx; i++) {
+ if (!mmu->domains[i])
+ continue;
+
+ ipmmu_domain_setup_context(mmu->domains[i]);
+ }
+ }
+
+ /* Re-enable active micro-TLBs */
+ for (i = 0; i < mmu->features->num_utlbs; i++) {
+ if (mmu->utlb_ctx[i] == IPMMU_CTX_INVALID)
+ continue;
+
+ ipmmu_utlb_enable(mmu->root->domains[mmu->utlb_ctx[i]], i);
+ }
+
+ return 0;
+}
+
+static const struct dev_pm_ops ipmmu_pm = {
+ SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(NULL, ipmmu_resume_noirq)
+};
+#define DEV_PM_OPS &ipmmu_pm
+#else
+#define DEV_PM_OPS NULL
+#endif /* CONFIG_PM_SLEEP */
+
+static struct platform_driver ipmmu_driver = {
+ .driver = {
+ .name = "ipmmu-vmsa",
+ .of_match_table = of_match_ptr(ipmmu_of_ids),
+ .pm = DEV_PM_OPS,
+ },
+ .probe = ipmmu_probe,
+ .remove = ipmmu_remove,
+};
+builtin_platform_driver(ipmmu_driver);