diff options
Diffstat (limited to 'drivers/iommu/ipmmu-vmsa.c')
| -rw-r--r-- | drivers/iommu/ipmmu-vmsa.c | 895 |
1 files changed, 895 insertions, 0 deletions
diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c new file mode 100644 index 000000000..1a67c531a --- /dev/null +++ b/drivers/iommu/ipmmu-vmsa.c @@ -0,0 +1,895 @@ +/* + * IPMMU VMSA + * + * Copyright (C) 2014 Renesas Electronics Corporation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + */ + +#include <linux/delay.h> +#include <linux/dma-mapping.h> +#include <linux/err.h> +#include <linux/export.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/iommu.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/sizes.h> +#include <linux/slab.h> + +#include <asm/dma-iommu.h> +#include <asm/pgalloc.h> + +#include "io-pgtable.h" + +struct ipmmu_vmsa_device { + struct device *dev; + void __iomem *base; + struct list_head list; + + unsigned int num_utlbs; + + 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; + spinlock_t lock; /* Protects mappings */ +}; + +struct ipmmu_vmsa_archdata { + struct ipmmu_vmsa_device *mmu; + unsigned int *utlbs; + unsigned int num_utlbs; +}; + +static DEFINE_SPINLOCK(ipmmu_devices_lock); +static LIST_HEAD(ipmmu_devices); + +static struct ipmmu_vmsa_domain *to_vmsa_domain(struct iommu_domain *dom) +{ + return container_of(dom, struct ipmmu_vmsa_domain, io_domain); +} + +#define TLB_LOOP_TIMEOUT 100 /* 100us */ + +/* ----------------------------------------------------------------------------- + * Registers Definition + */ + +#define IM_NS_ALIAS_OFFSET 0x800 + +#define IM_CTX_SIZE 0x40 + +#define IMCTR 0x0000 +#define IMCTR_TRE (1 << 17) +#define IMCTR_AFE (1 << 16) +#define IMCTR_RTSEL_MASK (3 << 4) +#define IMCTR_RTSEL_SHIFT 4 +#define IMCTR_TREN (1 << 3) +#define IMCTR_INTEN (1 << 2) +#define IMCTR_FLUSH (1 << 1) +#define IMCTR_MMUEN (1 << 0) + +#define IMCAAR 0x0004 + +#define IMTTBCR 0x0008 +#define IMTTBCR_EAE (1 << 31) +#define IMTTBCR_PMB (1 << 30) +#define IMTTBCR_SH1_NON_SHAREABLE (0 << 28) +#define IMTTBCR_SH1_OUTER_SHAREABLE (2 << 28) +#define IMTTBCR_SH1_INNER_SHAREABLE (3 << 28) +#define IMTTBCR_SH1_MASK (3 << 28) +#define IMTTBCR_ORGN1_NC (0 << 26) +#define IMTTBCR_ORGN1_WB_WA (1 << 26) +#define IMTTBCR_ORGN1_WT (2 << 26) +#define IMTTBCR_ORGN1_WB (3 << 26) +#define IMTTBCR_ORGN1_MASK (3 << 26) +#define IMTTBCR_IRGN1_NC (0 << 24) +#define IMTTBCR_IRGN1_WB_WA (1 << 24) +#define IMTTBCR_IRGN1_WT (2 << 24) +#define IMTTBCR_IRGN1_WB (3 << 24) +#define IMTTBCR_IRGN1_MASK (3 << 24) +#define IMTTBCR_TSZ1_MASK (7 << 16) +#define IMTTBCR_TSZ1_SHIFT 16 +#define IMTTBCR_SH0_NON_SHAREABLE (0 << 12) +#define IMTTBCR_SH0_OUTER_SHAREABLE (2 << 12) +#define IMTTBCR_SH0_INNER_SHAREABLE (3 << 12) +#define IMTTBCR_SH0_MASK (3 << 12) +#define IMTTBCR_ORGN0_NC (0 << 10) +#define IMTTBCR_ORGN0_WB_WA (1 << 10) +#define IMTTBCR_ORGN0_WT (2 << 10) +#define IMTTBCR_ORGN0_WB (3 << 10) +#define IMTTBCR_ORGN0_MASK (3 << 10) +#define IMTTBCR_IRGN0_NC (0 << 8) +#define IMTTBCR_IRGN0_WB_WA (1 << 8) +#define IMTTBCR_IRGN0_WT (2 << 8) +#define IMTTBCR_IRGN0_WB (3 << 8) +#define IMTTBCR_IRGN0_MASK (3 << 8) +#define IMTTBCR_SL0_LVL_2 (0 << 4) +#define IMTTBCR_SL0_LVL_1 (1 << 4) +#define IMTTBCR_TSZ0_MASK (7 << 0) +#define IMTTBCR_TSZ0_SHIFT O + +#define IMBUSCR 0x000c +#define IMBUSCR_DVM (1 << 2) +#define IMBUSCR_BUSSEL_SYS (0 << 0) +#define IMBUSCR_BUSSEL_CCI (1 << 0) +#define IMBUSCR_BUSSEL_IMCAAR (2 << 0) +#define IMBUSCR_BUSSEL_CCI_IMCAAR (3 << 0) +#define IMBUSCR_BUSSEL_MASK (3 << 0) + +#define IMTTLBR0 0x0010 +#define IMTTUBR0 0x0014 +#define IMTTLBR1 0x0018 +#define IMTTUBR1 0x001c + +#define IMSTR 0x0020 +#define IMSTR_ERRLVL_MASK (3 << 12) +#define IMSTR_ERRLVL_SHIFT 12 +#define IMSTR_ERRCODE_TLB_FORMAT (1 << 8) +#define IMSTR_ERRCODE_ACCESS_PERM (4 << 8) +#define IMSTR_ERRCODE_SECURE_ACCESS (5 << 8) +#define IMSTR_ERRCODE_MASK (7 << 8) +#define IMSTR_MHIT (1 << 4) +#define IMSTR_ABORT (1 << 2) +#define IMSTR_PF (1 << 1) +#define IMSTR_TF (1 << 0) + +#define IMMAIR0 0x0028 +#define IMMAIR1 0x002c +#define IMMAIR_ATTR_MASK 0xff +#define IMMAIR_ATTR_DEVICE 0x04 +#define IMMAIR_ATTR_NC 0x44 +#define IMMAIR_ATTR_WBRWA 0xff +#define IMMAIR_ATTR_SHIFT(n) ((n) << 3) +#define IMMAIR_ATTR_IDX_NC 0 +#define IMMAIR_ATTR_IDX_WBRWA 1 +#define IMMAIR_ATTR_IDX_DEV 2 + +#define IMEAR 0x0030 + +#define IMPCTR 0x0200 +#define IMPSTR 0x0208 +#define IMPEAR 0x020c +#define IMPMBA(n) (0x0280 + ((n) * 4)) +#define IMPMBD(n) (0x02c0 + ((n) * 4)) + +#define IMUCTR(n) (0x0300 + ((n) * 16)) +#define IMUCTR_FIXADDEN (1 << 31) +#define IMUCTR_FIXADD_MASK (0xff << 16) +#define IMUCTR_FIXADD_SHIFT 16 +#define IMUCTR_TTSEL_MMU(n) ((n) << 4) +#define IMUCTR_TTSEL_PMB (8 << 4) +#define IMUCTR_TTSEL_MASK (15 << 4) +#define IMUCTR_FLUSH (1 << 1) +#define IMUCTR_MMUEN (1 << 0) + +#define IMUASID(n) (0x0308 + ((n) * 16)) +#define IMUASID_ASID8_MASK (0xff << 8) +#define IMUASID_ASID8_SHIFT 8 +#define IMUASID_ASID0_MASK (0xff << 0) +#define IMUASID_ASID0_SHIFT 0 + +/* ----------------------------------------------------------------------------- + * 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 u32 ipmmu_ctx_read(struct ipmmu_vmsa_domain *domain, unsigned int reg) +{ + return ipmmu_read(domain->mmu, domain->context_id * IM_CTX_SIZE + reg); +} + +static void ipmmu_ctx_write(struct ipmmu_vmsa_domain *domain, unsigned int reg, + u32 data) +{ + ipmmu_write(domain->mmu, domain->context_id * IM_CTX_SIZE + reg, 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(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(domain, IMCTR); + reg |= IMCTR_FLUSH; + ipmmu_ctx_write(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_write(mmu, IMUASID(utlb), 0); + /* TODO: Do we need to flush the microTLB ? */ + ipmmu_write(mmu, IMUCTR(utlb), + IMUCTR_TTSEL_MMU(domain->context_id) | IMUCTR_FLUSH | + IMUCTR_MMUEN); +} + +/* + * 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_write(mmu, IMUCTR(utlb), 0); +} + +static void ipmmu_tlb_flush_all(void *cookie) +{ + struct ipmmu_vmsa_domain *domain = cookie; + + ipmmu_tlb_invalidate(domain); +} + +static void ipmmu_tlb_add_flush(unsigned long iova, size_t size, bool leaf, + void *cookie) +{ + /* The hardware doesn't support selective TLB flush. */ +} + +static void ipmmu_flush_pgtable(void *ptr, size_t size, void *cookie) +{ + unsigned long offset = (unsigned long)ptr & ~PAGE_MASK; + struct ipmmu_vmsa_domain *domain = cookie; + + /* + * TODO: Add support for coherent walk through CCI with DVM and remove + * cache handling. + */ + dma_map_page(domain->mmu->dev, virt_to_page(ptr), offset, size, + DMA_TO_DEVICE); +} + +static struct iommu_gather_ops ipmmu_gather_ops = { + .tlb_flush_all = ipmmu_tlb_flush_all, + .tlb_add_flush = ipmmu_tlb_add_flush, + .tlb_sync = ipmmu_tlb_flush_all, + .flush_pgtable = ipmmu_flush_pgtable, +}; + +/* ----------------------------------------------------------------------------- + * Domain/Context Management + */ + +static int ipmmu_domain_init_context(struct ipmmu_vmsa_domain *domain) +{ + phys_addr_t ttbr; + + /* + * 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_gather_ops; + + domain->iop = alloc_io_pgtable_ops(ARM_32_LPAE_S1, &domain->cfg, + domain); + if (!domain->iop) + return -EINVAL; + + /* + * TODO: When adding support for multiple contexts, find an unused + * context. + */ + domain->context_id = 0; + + /* TTBR0 */ + ttbr = domain->cfg.arm_lpae_s1_cfg.ttbr[0]; + ipmmu_ctx_write(domain, IMTTLBR0, ttbr); + ipmmu_ctx_write(domain, IMTTUBR0, ttbr >> 32); + + /* + * TTBCR + * We use long descriptors with inner-shareable WBWA tables and allocate + * the whole 32-bit VA space to TTBR0. + */ + ipmmu_ctx_write(domain, IMTTBCR, IMTTBCR_EAE | + IMTTBCR_SH0_INNER_SHAREABLE | IMTTBCR_ORGN0_WB_WA | + IMTTBCR_IRGN0_WB_WA | IMTTBCR_SL0_LVL_1); + + /* MAIR0 */ + ipmmu_ctx_write(domain, IMMAIR0, domain->cfg.arm_lpae_s1_cfg.mair[0]); + + /* IMBUSCR */ + ipmmu_ctx_write(domain, IMBUSCR, + ipmmu_ctx_read(domain, IMBUSCR) & + ~(IMBUSCR_DVM | IMBUSCR_BUSSEL_MASK)); + + /* + * IMSTR + * Clear all interrupt flags. + */ + ipmmu_ctx_write(domain, IMSTR, ipmmu_ctx_read(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(domain, IMCTR, IMCTR_INTEN | IMCTR_FLUSH | IMCTR_MMUEN); + + return 0; +} + +static void ipmmu_domain_destroy_context(struct ipmmu_vmsa_domain *domain) +{ + /* + * Disable the context. Flush the TLB as required when modifying the + * context registers. + * + * TODO: Is TLB flush really needed ? + */ + ipmmu_ctx_write(domain, IMCTR, IMCTR_FLUSH); + ipmmu_tlb_sync(domain); +} + +/* ----------------------------------------------------------------------------- + * 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; + u32 status; + u32 iova; + + status = ipmmu_ctx_read(domain, IMSTR); + if (!(status & err_mask)) + return IRQ_NONE; + + iova = ipmmu_ctx_read(domain, IMEAR); + + /* + * 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(domain, IMSTR, 0); + + /* Log fatal errors. */ + if (status & IMSTR_MHIT) + dev_err_ratelimited(mmu->dev, "Multiple TLB hits @0x%08x\n", + iova); + if (status & IMSTR_ABORT) + dev_err_ratelimited(mmu->dev, "Page Table Walk Abort @0x%08x\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%08x\n", + status, iova); + + return IRQ_HANDLED; +} + +static irqreturn_t ipmmu_irq(int irq, void *dev) +{ + struct ipmmu_vmsa_device *mmu = dev; + struct iommu_domain *io_domain; + struct ipmmu_vmsa_domain *domain; + + if (!mmu->mapping) + return IRQ_NONE; + + io_domain = mmu->mapping->domain; + domain = to_vmsa_domain(io_domain); + + return ipmmu_domain_irq(domain); +} + +/* ----------------------------------------------------------------------------- + * IOMMU Operations + */ + +static struct iommu_domain *ipmmu_domain_alloc(unsigned type) +{ + struct ipmmu_vmsa_domain *domain; + + if (type != IOMMU_DOMAIN_UNMANAGED) + return NULL; + + domain = kzalloc(sizeof(*domain), GFP_KERNEL); + if (!domain) + return NULL; + + spin_lock_init(&domain->lock); + + 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 ipmmu_vmsa_archdata *archdata = dev->archdata.iommu; + struct ipmmu_vmsa_device *mmu = archdata->mmu; + struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain); + unsigned long flags; + unsigned int i; + int ret = 0; + + if (!mmu) { + dev_err(dev, "Cannot attach to IPMMU\n"); + return -ENXIO; + } + + spin_lock_irqsave(&domain->lock, flags); + + if (!domain->mmu) { + /* The domain hasn't been used yet, initialize it. */ + domain->mmu = mmu; + ret = ipmmu_domain_init_context(domain); + } 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; + } + + spin_unlock_irqrestore(&domain->lock, flags); + + if (ret < 0) + return ret; + + for (i = 0; i < archdata->num_utlbs; ++i) + ipmmu_utlb_enable(domain, archdata->utlbs[i]); + + return 0; +} + +static void ipmmu_detach_device(struct iommu_domain *io_domain, + struct device *dev) +{ + struct ipmmu_vmsa_archdata *archdata = dev->archdata.iommu; + struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain); + unsigned int i; + + for (i = 0; i < archdata->num_utlbs; ++i) + ipmmu_utlb_disable(domain, archdata->utlbs[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) +{ + struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain); + + if (!domain) + return -ENODEV; + + return domain->iop->map(domain->iop, iova, paddr, size, prot); +} + +static size_t ipmmu_unmap(struct iommu_domain *io_domain, unsigned long iova, + size_t size) +{ + struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain); + + return domain->iop->unmap(domain->iop, iova, size); +} + +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_find_utlbs(struct ipmmu_vmsa_device *mmu, struct device *dev, + unsigned int *utlbs, unsigned int num_utlbs) +{ + unsigned int i; + + for (i = 0; i < num_utlbs; ++i) { + struct of_phandle_args args; + int ret; + + ret = of_parse_phandle_with_args(dev->of_node, "iommus", + "#iommu-cells", i, &args); + if (ret < 0) + return ret; + + of_node_put(args.np); + + if (args.np != mmu->dev->of_node || args.args_count != 1) + return -EINVAL; + + utlbs[i] = args.args[0]; + } + + return 0; +} + +static int ipmmu_add_device(struct device *dev) +{ + struct ipmmu_vmsa_archdata *archdata; + struct ipmmu_vmsa_device *mmu; + struct iommu_group *group = NULL; + unsigned int *utlbs; + unsigned int i; + int num_utlbs; + int ret = -ENODEV; + + if (dev->archdata.iommu) { + dev_warn(dev, "IOMMU driver already assigned to device %s\n", + dev_name(dev)); + return -EINVAL; + } + + /* Find the master corresponding to the device. */ + + num_utlbs = of_count_phandle_with_args(dev->of_node, "iommus", + "#iommu-cells"); + if (num_utlbs < 0) + return -ENODEV; + + utlbs = kcalloc(num_utlbs, sizeof(*utlbs), GFP_KERNEL); + if (!utlbs) + return -ENOMEM; + + spin_lock(&ipmmu_devices_lock); + + list_for_each_entry(mmu, &ipmmu_devices, list) { + ret = ipmmu_find_utlbs(mmu, dev, utlbs, num_utlbs); + if (!ret) { + /* + * TODO Take a reference to the MMU to protect + * against device removal. + */ + break; + } + } + + spin_unlock(&ipmmu_devices_lock); + + if (ret < 0) + return -ENODEV; + + for (i = 0; i < num_utlbs; ++i) { + if (utlbs[i] >= mmu->num_utlbs) { + ret = -EINVAL; + goto error; + } + } + + /* Create a device group and add the device to it. */ + group = iommu_group_alloc(); + if (IS_ERR(group)) { + dev_err(dev, "Failed to allocate IOMMU group\n"); + ret = PTR_ERR(group); + goto error; + } + + ret = iommu_group_add_device(group, dev); + iommu_group_put(group); + + if (ret < 0) { + dev_err(dev, "Failed to add device to IPMMU group\n"); + group = NULL; + goto error; + } + + archdata = kzalloc(sizeof(*archdata), GFP_KERNEL); + if (!archdata) { + ret = -ENOMEM; + goto error; + } + + archdata->mmu = mmu; + archdata->utlbs = utlbs; + archdata->num_utlbs = num_utlbs; + dev->archdata.iommu = archdata; + + /* + * 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: + arm_iommu_release_mapping(mmu->mapping); + + kfree(dev->archdata.iommu); + kfree(utlbs); + + dev->archdata.iommu = NULL; + + if (!IS_ERR_OR_NULL(group)) + iommu_group_remove_device(dev); + + return ret; +} + +static void ipmmu_remove_device(struct device *dev) +{ + struct ipmmu_vmsa_archdata *archdata = dev->archdata.iommu; + + arm_iommu_detach_device(dev); + iommu_group_remove_device(dev); + + kfree(archdata->utlbs); + kfree(archdata); + + dev->archdata.iommu = NULL; +} + +static const struct iommu_ops ipmmu_ops = { + .domain_alloc = ipmmu_domain_alloc, + .domain_free = ipmmu_domain_free, + .attach_dev = ipmmu_attach_device, + .detach_dev = ipmmu_detach_device, + .map = ipmmu_map, + .unmap = ipmmu_unmap, + .map_sg = default_iommu_map_sg, + .iova_to_phys = ipmmu_iova_to_phys, + .add_device = ipmmu_add_device, + .remove_device = ipmmu_remove_device, + .pgsize_bitmap = SZ_1G | SZ_2M | SZ_4K, +}; + +/* ----------------------------------------------------------------------------- + * Probe/remove and init + */ + +static void ipmmu_device_reset(struct ipmmu_vmsa_device *mmu) +{ + unsigned int i; + + /* Disable all contexts. */ + for (i = 0; i < 4; ++i) + ipmmu_write(mmu, i * IM_CTX_SIZE + IMCTR, 0); +} + +static int ipmmu_probe(struct platform_device *pdev) +{ + struct ipmmu_vmsa_device *mmu; + struct resource *res; + int irq; + int ret; + + if (!IS_ENABLED(CONFIG_OF) && !pdev->dev.platform_data) { + dev_err(&pdev->dev, "missing platform data\n"); + return -EINVAL; + } + + 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; + mmu->num_utlbs = 32; + + /* 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. + */ + mmu->base += IM_NS_ALIAS_OFFSET; + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_err(&pdev->dev, "no IRQ found\n"); + 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); + + /* + * 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. + */ + + spin_lock(&ipmmu_devices_lock); + list_add(&mmu->list, &ipmmu_devices); + spin_unlock(&ipmmu_devices_lock); + + platform_set_drvdata(pdev, mmu); + + return 0; +} + +static int ipmmu_remove(struct platform_device *pdev) +{ + struct ipmmu_vmsa_device *mmu = platform_get_drvdata(pdev); + + spin_lock(&ipmmu_devices_lock); + list_del(&mmu->list); + spin_unlock(&ipmmu_devices_lock); + + arm_iommu_release_mapping(mmu->mapping); + + ipmmu_device_reset(mmu); + + return 0; +} + +static const struct of_device_id ipmmu_of_ids[] = { + { .compatible = "renesas,ipmmu-vmsa", }, + { } +}; + +static struct platform_driver ipmmu_driver = { + .driver = { + .name = "ipmmu-vmsa", + .of_match_table = of_match_ptr(ipmmu_of_ids), + }, + .probe = ipmmu_probe, + .remove = ipmmu_remove, +}; + +static int __init ipmmu_init(void) +{ + int ret; + + ret = platform_driver_register(&ipmmu_driver); + if (ret < 0) + return ret; + + if (!iommu_present(&platform_bus_type)) + bus_set_iommu(&platform_bus_type, &ipmmu_ops); + + return 0; +} + +static void __exit ipmmu_exit(void) +{ + return platform_driver_unregister(&ipmmu_driver); +} + +subsys_initcall(ipmmu_init); +module_exit(ipmmu_exit); + +MODULE_DESCRIPTION("IOMMU API for Renesas VMSA-compatible IPMMU"); +MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>"); +MODULE_LICENSE("GPL v2"); |