// SPDX-License-Identifier: GPL-2.0-only /* * Apple DART (Device Address Resolution Table) IOMMU driver * * Copyright (C) 2021 The Asahi Linux Contributors * * Based on arm/arm-smmu/arm-ssmu.c and arm/arm-smmu-v3/arm-smmu-v3.c * Copyright (C) 2013 ARM Limited * Copyright (C) 2015 ARM Limited * and on exynos-iommu.c * Copyright (c) 2011,2016 Samsung Electronics Co., Ltd. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define DART_MAX_STREAMS 16 #define DART_MAX_TTBR 4 #define MAX_DARTS_PER_DEVICE 2 #define DART_STREAM_ALL 0xffff #define DART_PARAMS1 0x00 #define DART_PARAMS_PAGE_SHIFT GENMASK(27, 24) #define DART_PARAMS2 0x04 #define DART_PARAMS_BYPASS_SUPPORT BIT(0) #define DART_STREAM_COMMAND 0x20 #define DART_STREAM_COMMAND_BUSY BIT(2) #define DART_STREAM_COMMAND_INVALIDATE BIT(20) #define DART_STREAM_SELECT 0x34 #define DART_ERROR 0x40 #define DART_ERROR_STREAM GENMASK(27, 24) #define DART_ERROR_CODE GENMASK(11, 0) #define DART_ERROR_FLAG BIT(31) #define DART_ERROR_READ_FAULT BIT(4) #define DART_ERROR_WRITE_FAULT BIT(3) #define DART_ERROR_NO_PTE BIT(2) #define DART_ERROR_NO_PMD BIT(1) #define DART_ERROR_NO_TTBR BIT(0) #define DART_CONFIG 0x60 #define DART_CONFIG_LOCK BIT(15) #define DART_STREAM_COMMAND_BUSY_TIMEOUT 100 #define DART_ERROR_ADDR_HI 0x54 #define DART_ERROR_ADDR_LO 0x50 #define DART_STREAMS_ENABLE 0xfc #define DART_TCR(sid) (0x100 + 4 * (sid)) #define DART_TCR_TRANSLATE_ENABLE BIT(7) #define DART_TCR_BYPASS0_ENABLE BIT(8) #define DART_TCR_BYPASS1_ENABLE BIT(12) #define DART_TTBR(sid, idx) (0x200 + 16 * (sid) + 4 * (idx)) #define DART_TTBR_VALID BIT(31) #define DART_TTBR_SHIFT 12 /* * Private structure associated with each DART device. * * @dev: device struct * @regs: mapped MMIO region * @irq: interrupt number, can be shared with other DARTs * @clks: clocks associated with this DART * @num_clks: number of @clks * @lock: lock for hardware operations involving this dart * @pgsize: pagesize supported by this DART * @supports_bypass: indicates if this DART supports bypass mode * @force_bypass: force bypass mode due to pagesize mismatch? * @sid2group: maps stream ids to iommu_groups * @iommu: iommu core device */ struct apple_dart { struct device *dev; void __iomem *regs; int irq; struct clk_bulk_data *clks; int num_clks; spinlock_t lock; u32 pgsize; u32 supports_bypass : 1; u32 force_bypass : 1; struct iommu_group *sid2group[DART_MAX_STREAMS]; struct iommu_device iommu; }; /* * Convenience struct to identify streams. * * The normal variant is used inside apple_dart_master_cfg which isn't written * to concurrently. * The atomic variant is used inside apple_dart_domain where we have to guard * against races from potential parallel calls to attach/detach_device. * Note that even inside the atomic variant the apple_dart pointer is not * protected: This pointer is initialized once under the domain init mutex * and never changed again afterwards. Devices with different dart pointers * cannot be attached to the same domain. * * @dart dart pointer * @sid stream id bitmap */ struct apple_dart_stream_map { struct apple_dart *dart; unsigned long sidmap; }; struct apple_dart_atomic_stream_map { struct apple_dart *dart; atomic64_t sidmap; }; /* * This structure is attached to each iommu domain handled by a DART. * * @pgtbl_ops: pagetable ops allocated by io-pgtable * @finalized: true if the domain has been completely initialized * @init_lock: protects domain initialization * @stream_maps: streams attached to this domain (valid for DMA/UNMANAGED only) * @domain: core iommu domain pointer */ struct apple_dart_domain { struct io_pgtable_ops *pgtbl_ops; bool finalized; struct mutex init_lock; struct apple_dart_atomic_stream_map stream_maps[MAX_DARTS_PER_DEVICE]; struct iommu_domain domain; }; /* * This structure is attached to devices with dev_iommu_priv_set() on of_xlate * and contains a list of streams bound to this device. * So far the worst case seen is a single device with two streams * from different darts, such that this simple static array is enough. * * @streams: streams for this device */ struct apple_dart_master_cfg { struct apple_dart_stream_map stream_maps[MAX_DARTS_PER_DEVICE]; }; /* * Helper macro to iterate over apple_dart_master_cfg.stream_maps and * apple_dart_domain.stream_maps * * @i int used as loop variable * @base pointer to base struct (apple_dart_master_cfg or apple_dart_domain) * @stream pointer to the apple_dart_streams struct for each loop iteration */ #define for_each_stream_map(i, base, stream_map) \ for (i = 0, stream_map = &(base)->stream_maps[0]; \ i < MAX_DARTS_PER_DEVICE && stream_map->dart; \ stream_map = &(base)->stream_maps[++i]) static struct platform_driver apple_dart_driver; static const struct iommu_ops apple_dart_iommu_ops; static struct apple_dart_domain *to_dart_domain(struct iommu_domain *dom) { return container_of(dom, struct apple_dart_domain, domain); } static void apple_dart_hw_enable_translation(struct apple_dart_stream_map *stream_map) { int sid; for_each_set_bit(sid, &stream_map->sidmap, DART_MAX_STREAMS) writel(DART_TCR_TRANSLATE_ENABLE, stream_map->dart->regs + DART_TCR(sid)); } static void apple_dart_hw_disable_dma(struct apple_dart_stream_map *stream_map) { int sid; for_each_set_bit(sid, &stream_map->sidmap, DART_MAX_STREAMS) writel(0, stream_map->dart->regs + DART_TCR(sid)); } static void apple_dart_hw_enable_bypass(struct apple_dart_stream_map *stream_map) { int sid; WARN_ON(!stream_map->dart->supports_bypass); for_each_set_bit(sid, &stream_map->sidmap, DART_MAX_STREAMS) writel(DART_TCR_BYPASS0_ENABLE | DART_TCR_BYPASS1_ENABLE, stream_map->dart->regs + DART_TCR(sid)); } static void apple_dart_hw_set_ttbr(struct apple_dart_stream_map *stream_map, u8 idx, phys_addr_t paddr) { int sid; WARN_ON(paddr & ((1 << DART_TTBR_SHIFT) - 1)); for_each_set_bit(sid, &stream_map->sidmap, DART_MAX_STREAMS) writel(DART_TTBR_VALID | (paddr >> DART_TTBR_SHIFT), stream_map->dart->regs + DART_TTBR(sid, idx)); } static void apple_dart_hw_clear_ttbr(struct apple_dart_stream_map *stream_map, u8 idx) { int sid; for_each_set_bit(sid, &stream_map->sidmap, DART_MAX_STREAMS) writel(0, stream_map->dart->regs + DART_TTBR(sid, idx)); } static void apple_dart_hw_clear_all_ttbrs(struct apple_dart_stream_map *stream_map) { int i; for (i = 0; i < DART_MAX_TTBR; ++i) apple_dart_hw_clear_ttbr(stream_map, i); } static int apple_dart_hw_stream_command(struct apple_dart_stream_map *stream_map, u32 command) { unsigned long flags; int ret; u32 command_reg; spin_lock_irqsave(&stream_map->dart->lock, flags); writel(stream_map->sidmap, stream_map->dart->regs + DART_STREAM_SELECT); writel(command, stream_map->dart->regs + DART_STREAM_COMMAND); ret = readl_poll_timeout_atomic( stream_map->dart->regs + DART_STREAM_COMMAND, command_reg, !(command_reg & DART_STREAM_COMMAND_BUSY), 1, DART_STREAM_COMMAND_BUSY_TIMEOUT); spin_unlock_irqrestore(&stream_map->dart->lock, flags); if (ret) { dev_err(stream_map->dart->dev, "busy bit did not clear after command %x for streams %lx\n", command, stream_map->sidmap); return ret; } return 0; } static int apple_dart_hw_invalidate_tlb(struct apple_dart_stream_map *stream_map) { return apple_dart_hw_stream_command(stream_map, DART_STREAM_COMMAND_INVALIDATE); } static int apple_dart_hw_reset(struct apple_dart *dart) { u32 config; struct apple_dart_stream_map stream_map; config = readl(dart->regs + DART_CONFIG); if (config & DART_CONFIG_LOCK) { dev_err(dart->dev, "DART is locked down until reboot: %08x\n", config); return -EINVAL; } stream_map.dart = dart; stream_map.sidmap = DART_STREAM_ALL; apple_dart_hw_disable_dma(&stream_map); apple_dart_hw_clear_all_ttbrs(&stream_map); /* enable all streams globally since TCR is used to control isolation */ writel(DART_STREAM_ALL, dart->regs + DART_STREAMS_ENABLE); /* clear any pending errors before the interrupt is unmasked */ writel(readl(dart->regs + DART_ERROR), dart->regs + DART_ERROR); return apple_dart_hw_invalidate_tlb(&stream_map); } static void apple_dart_domain_flush_tlb(struct apple_dart_domain *domain) { int i; struct apple_dart_atomic_stream_map *domain_stream_map; struct apple_dart_stream_map stream_map; for_each_stream_map(i, domain, domain_stream_map) { stream_map.dart = domain_stream_map->dart; stream_map.sidmap = atomic64_read(&domain_stream_map->sidmap); apple_dart_hw_invalidate_tlb(&stream_map); } } static void apple_dart_flush_iotlb_all(struct iommu_domain *domain) { apple_dart_domain_flush_tlb(to_dart_domain(domain)); } static void apple_dart_iotlb_sync(struct iommu_domain *domain, struct iommu_iotlb_gather *gather) { apple_dart_domain_flush_tlb(to_dart_domain(domain)); } static void apple_dart_iotlb_sync_map(struct iommu_domain *domain, unsigned long iova, size_t size) { apple_dart_domain_flush_tlb(to_dart_domain(domain)); } static phys_addr_t apple_dart_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova) { struct apple_dart_domain *dart_domain = to_dart_domain(domain); struct io_pgtable_ops *ops = dart_domain->pgtbl_ops; if (!ops) return 0; return ops->iova_to_phys(ops, iova); } static int apple_dart_map_pages(struct iommu_domain *domain, unsigned long iova, phys_addr_t paddr, size_t pgsize, size_t pgcount, int prot, gfp_t gfp, size_t *mapped) { struct apple_dart_domain *dart_domain = to_dart_domain(domain); struct io_pgtable_ops *ops = dart_domain->pgtbl_ops; if (!ops) return -ENODEV; return ops->map_pages(ops, iova, paddr, pgsize, pgcount, prot, gfp, mapped); } static size_t apple_dart_unmap_pages(struct iommu_domain *domain, unsigned long iova, size_t pgsize, size_t pgcount, struct iommu_iotlb_gather *gather) { struct apple_dart_domain *dart_domain = to_dart_domain(domain); struct io_pgtable_ops *ops = dart_domain->pgtbl_ops; return ops->unmap_pages(ops, iova, pgsize, pgcount, gather); } static void apple_dart_setup_translation(struct apple_dart_domain *domain, struct apple_dart_stream_map *stream_map) { int i; struct io_pgtable_cfg *pgtbl_cfg = &io_pgtable_ops_to_pgtable(domain->pgtbl_ops)->cfg; for (i = 0; i < pgtbl_cfg->apple_dart_cfg.n_ttbrs; ++i) apple_dart_hw_set_ttbr(stream_map, i, pgtbl_cfg->apple_dart_cfg.ttbr[i]); for (; i < DART_MAX_TTBR; ++i) apple_dart_hw_clear_ttbr(stream_map, i); apple_dart_hw_enable_translation(stream_map); apple_dart_hw_invalidate_tlb(stream_map); } static int apple_dart_finalize_domain(struct iommu_domain *domain, struct apple_dart_master_cfg *cfg) { struct apple_dart_domain *dart_domain = to_dart_domain(domain); struct apple_dart *dart = cfg->stream_maps[0].dart; struct io_pgtable_cfg pgtbl_cfg; int ret = 0; int i; mutex_lock(&dart_domain->init_lock); if (dart_domain->finalized) goto done; for (i = 0; i < MAX_DARTS_PER_DEVICE; ++i) { dart_domain->stream_maps[i].dart = cfg->stream_maps[i].dart; atomic64_set(&dart_domain->stream_maps[i].sidmap, cfg->stream_maps[i].sidmap); } pgtbl_cfg = (struct io_pgtable_cfg){ .pgsize_bitmap = dart->pgsize, .ias = 32, .oas = 36, .coherent_walk = 1, .iommu_dev = dart->dev, }; dart_domain->pgtbl_ops = alloc_io_pgtable_ops(APPLE_DART, &pgtbl_cfg, domain); if (!dart_domain->pgtbl_ops) { ret = -ENOMEM; goto done; } domain->pgsize_bitmap = pgtbl_cfg.pgsize_bitmap; domain->geometry.aperture_start = 0; domain->geometry.aperture_end = DMA_BIT_MASK(32); domain->geometry.force_aperture = true; dart_domain->finalized = true; done: mutex_unlock(&dart_domain->init_lock); return ret; } static int apple_dart_mod_streams(struct apple_dart_atomic_stream_map *domain_maps, struct apple_dart_stream_map *master_maps, bool add_streams) { int i; for (i = 0; i < MAX_DARTS_PER_DEVICE; ++i) { if (domain_maps[i].dart != master_maps[i].dart) return -EINVAL; } for (i = 0; i < MAX_DARTS_PER_DEVICE; ++i) { if (!domain_maps[i].dart) break; if (add_streams) atomic64_or(master_maps[i].sidmap, &domain_maps[i].sidmap); else atomic64_and(~master_maps[i].sidmap, &domain_maps[i].sidmap); } return 0; } static int apple_dart_domain_add_streams(struct apple_dart_domain *domain, struct apple_dart_master_cfg *cfg) { return apple_dart_mod_streams(domain->stream_maps, cfg->stream_maps, true); } static int apple_dart_domain_remove_streams(struct apple_dart_domain *domain, struct apple_dart_master_cfg *cfg) { return apple_dart_mod_streams(domain->stream_maps, cfg->stream_maps, false); } static int apple_dart_attach_dev(struct iommu_domain *domain, struct device *dev) { int ret, i; struct apple_dart_stream_map *stream_map; struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev); struct apple_dart_domain *dart_domain = to_dart_domain(domain); if (cfg->stream_maps[0].dart->force_bypass && domain->type != IOMMU_DOMAIN_IDENTITY) return -EINVAL; if (!cfg->stream_maps[0].dart->supports_bypass && domain->type == IOMMU_DOMAIN_IDENTITY) return -EINVAL; ret = apple_dart_finalize_domain(domain, cfg); if (ret) return ret; switch (domain->type) { case IOMMU_DOMAIN_DMA: case IOMMU_DOMAIN_UNMANAGED: ret = apple_dart_domain_add_streams(dart_domain, cfg); if (ret) return ret; for_each_stream_map(i, cfg, stream_map) apple_dart_setup_translation(dart_domain, stream_map); break; case IOMMU_DOMAIN_BLOCKED: for_each_stream_map(i, cfg, stream_map) apple_dart_hw_disable_dma(stream_map); break; case IOMMU_DOMAIN_IDENTITY: for_each_stream_map(i, cfg, stream_map) apple_dart_hw_enable_bypass(stream_map); break; } return ret; } static void apple_dart_detach_dev(struct iommu_domain *domain, struct device *dev) { int i; struct apple_dart_stream_map *stream_map; struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev); struct apple_dart_domain *dart_domain = to_dart_domain(domain); for_each_stream_map(i, cfg, stream_map) apple_dart_hw_disable_dma(stream_map); if (domain->type == IOMMU_DOMAIN_DMA || domain->type == IOMMU_DOMAIN_UNMANAGED) apple_dart_domain_remove_streams(dart_domain, cfg); } static struct iommu_device *apple_dart_probe_device(struct device *dev) { struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev); struct apple_dart_stream_map *stream_map; int i; if (!cfg) return ERR_PTR(-ENODEV); for_each_stream_map(i, cfg, stream_map) device_link_add( dev, stream_map->dart->dev, DL_FLAG_PM_RUNTIME | DL_FLAG_AUTOREMOVE_SUPPLIER); return &cfg->stream_maps[0].dart->iommu; } static void apple_dart_release_device(struct device *dev) { struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev); if (!cfg) return; dev_iommu_priv_set(dev, NULL); kfree(cfg); } static struct iommu_domain *apple_dart_domain_alloc(unsigned int type) { struct apple_dart_domain *dart_domain; if (type != IOMMU_DOMAIN_DMA && type != IOMMU_DOMAIN_UNMANAGED && type != IOMMU_DOMAIN_IDENTITY && type != IOMMU_DOMAIN_BLOCKED) return NULL; dart_domain = kzalloc(sizeof(*dart_domain), GFP_KERNEL); if (!dart_domain) return NULL; mutex_init(&dart_domain->init_lock); /* no need to allocate pgtbl_ops or do any other finalization steps */ if (type == IOMMU_DOMAIN_IDENTITY || type == IOMMU_DOMAIN_BLOCKED) dart_domain->finalized = true; return &dart_domain->domain; } static void apple_dart_domain_free(struct iommu_domain *domain) { struct apple_dart_domain *dart_domain = to_dart_domain(domain); if (dart_domain->pgtbl_ops) free_io_pgtable_ops(dart_domain->pgtbl_ops); kfree(dart_domain); } static int apple_dart_of_xlate(struct device *dev, struct of_phandle_args *args) { struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev); struct platform_device *iommu_pdev = of_find_device_by_node(args->np); struct apple_dart *dart = platform_get_drvdata(iommu_pdev); struct apple_dart *cfg_dart; int i, sid; if (args->args_count != 1) return -EINVAL; sid = args->args[0]; if (!cfg) cfg = kzalloc(sizeof(*cfg), GFP_KERNEL); if (!cfg) return -ENOMEM; dev_iommu_priv_set(dev, cfg); cfg_dart = cfg->stream_maps[0].dart; if (cfg_dart) { if (cfg_dart->supports_bypass != dart->supports_bypass) return -EINVAL; if (cfg_dart->force_bypass != dart->force_bypass) return -EINVAL; if (cfg_dart->pgsize != dart->pgsize) return -EINVAL; } for (i = 0; i < MAX_DARTS_PER_DEVICE; ++i) { if (cfg->stream_maps[i].dart == dart) { cfg->stream_maps[i].sidmap |= 1 << sid; return 0; } } for (i = 0; i < MAX_DARTS_PER_DEVICE; ++i) { if (!cfg->stream_maps[i].dart) { cfg->stream_maps[i].dart = dart; cfg->stream_maps[i].sidmap = 1 << sid; return 0; } } return -EINVAL; } static DEFINE_MUTEX(apple_dart_groups_lock); static void apple_dart_release_group(void *iommu_data) { int i, sid; struct apple_dart_stream_map *stream_map; struct apple_dart_master_cfg *group_master_cfg = iommu_data; mutex_lock(&apple_dart_groups_lock); for_each_stream_map(i, group_master_cfg, stream_map) for_each_set_bit(sid, &stream_map->sidmap, DART_MAX_STREAMS) stream_map->dart->sid2group[sid] = NULL; kfree(iommu_data); mutex_unlock(&apple_dart_groups_lock); } static struct iommu_group *apple_dart_device_group(struct device *dev) { int i, sid; struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev); struct apple_dart_stream_map *stream_map; struct apple_dart_master_cfg *group_master_cfg; struct iommu_group *group = NULL; struct iommu_group *res = ERR_PTR(-EINVAL); mutex_lock(&apple_dart_groups_lock); for_each_stream_map(i, cfg, stream_map) { for_each_set_bit(sid, &stream_map->sidmap, DART_MAX_STREAMS) { struct iommu_group *stream_group = stream_map->dart->sid2group[sid]; if (group && group != stream_group) { res = ERR_PTR(-EINVAL); goto out; } group = stream_group; } } if (group) { res = iommu_group_ref_get(group); goto out; } #ifdef CONFIG_PCI if (dev_is_pci(dev)) group = pci_device_group(dev); else #endif group = generic_device_group(dev); res = ERR_PTR(-ENOMEM); if (!group) goto out; group_master_cfg = kmemdup(cfg, sizeof(*group_master_cfg), GFP_KERNEL); if (!group_master_cfg) { iommu_group_put(group); goto out; } iommu_group_set_iommudata(group, group_master_cfg, apple_dart_release_group); for_each_stream_map(i, cfg, stream_map) for_each_set_bit(sid, &stream_map->sidmap, DART_MAX_STREAMS) stream_map->dart->sid2group[sid] = group; res = group; out: mutex_unlock(&apple_dart_groups_lock); return res; } static int apple_dart_def_domain_type(struct device *dev) { struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev); if (cfg->stream_maps[0].dart->force_bypass) return IOMMU_DOMAIN_IDENTITY; if (!cfg->stream_maps[0].dart->supports_bypass) return IOMMU_DOMAIN_DMA; return 0; } #ifndef CONFIG_PCIE_APPLE_MSI_DOORBELL_ADDR /* Keep things compiling when CONFIG_PCI_APPLE isn't selected */ #define CONFIG_PCIE_APPLE_MSI_DOORBELL_ADDR 0 #endif #define DOORBELL_ADDR (CONFIG_PCIE_APPLE_MSI_DOORBELL_ADDR & PAGE_MASK) static void apple_dart_get_resv_regions(struct device *dev, struct list_head *head) { if (IS_ENABLED(CONFIG_PCIE_APPLE) && dev_is_pci(dev)) { struct iommu_resv_region *region; int prot = IOMMU_WRITE | IOMMU_NOEXEC | IOMMU_MMIO; region = iommu_alloc_resv_region(DOORBELL_ADDR, PAGE_SIZE, prot, IOMMU_RESV_MSI); if (!region) return; list_add_tail(®ion->list, head); } iommu_dma_get_resv_regions(dev, head); } static const struct iommu_ops apple_dart_iommu_ops = { .domain_alloc = apple_dart_domain_alloc, .domain_free = apple_dart_domain_free, .attach_dev = apple_dart_attach_dev, .detach_dev = apple_dart_detach_dev, .map_pages = apple_dart_map_pages, .unmap_pages = apple_dart_unmap_pages, .flush_iotlb_all = apple_dart_flush_iotlb_all, .iotlb_sync = apple_dart_iotlb_sync, .iotlb_sync_map = apple_dart_iotlb_sync_map, .iova_to_phys = apple_dart_iova_to_phys, .probe_device = apple_dart_probe_device, .release_device = apple_dart_release_device, .device_group = apple_dart_device_group, .of_xlate = apple_dart_of_xlate, .def_domain_type = apple_dart_def_domain_type, .get_resv_regions = apple_dart_get_resv_regions, .put_resv_regions = generic_iommu_put_resv_regions, .pgsize_bitmap = -1UL, /* Restricted during dart probe */ }; static irqreturn_t apple_dart_irq(int irq, void *dev) { struct apple_dart *dart = dev; const char *fault_name = NULL; u32 error = readl(dart->regs + DART_ERROR); u32 error_code = FIELD_GET(DART_ERROR_CODE, error); u32 addr_lo = readl(dart->regs + DART_ERROR_ADDR_LO); u32 addr_hi = readl(dart->regs + DART_ERROR_ADDR_HI); u64 addr = addr_lo | (((u64)addr_hi) << 32); u8 stream_idx = FIELD_GET(DART_ERROR_STREAM, error); if (!(error & DART_ERROR_FLAG)) return IRQ_NONE; /* there should only be a single bit set but let's use == to be sure */ if (error_code == DART_ERROR_READ_FAULT) fault_name = "READ FAULT"; else if (error_code == DART_ERROR_WRITE_FAULT) fault_name = "WRITE FAULT"; else if (error_code == DART_ERROR_NO_PTE) fault_name = "NO PTE FOR IOVA"; else if (error_code == DART_ERROR_NO_PMD) fault_name = "NO PMD FOR IOVA"; else if (error_code == DART_ERROR_NO_TTBR) fault_name = "NO TTBR FOR IOVA"; else fault_name = "unknown"; dev_err_ratelimited( dart->dev, "translation fault: status:0x%x stream:%d code:0x%x (%s) at 0x%llx", error, stream_idx, error_code, fault_name, addr); writel(error, dart->regs + DART_ERROR); return IRQ_HANDLED; } static int apple_dart_set_bus_ops(const struct iommu_ops *ops) { int ret; if (!iommu_present(&platform_bus_type)) { ret = bus_set_iommu(&platform_bus_type, ops); if (ret) return ret; } #ifdef CONFIG_PCI if (!iommu_present(&pci_bus_type)) { ret = bus_set_iommu(&pci_bus_type, ops); if (ret) { bus_set_iommu(&platform_bus_type, NULL); return ret; } } #endif return 0; } static int apple_dart_probe(struct platform_device *pdev) { int ret; u32 dart_params[2]; struct resource *res; struct apple_dart *dart; struct device *dev = &pdev->dev; dart = devm_kzalloc(dev, sizeof(*dart), GFP_KERNEL); if (!dart) return -ENOMEM; dart->dev = dev; spin_lock_init(&dart->lock); res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (resource_size(res) < 0x4000) { dev_err(dev, "MMIO region too small (%pr)\n", res); return -EINVAL; } dart->regs = devm_ioremap_resource(dev, res); if (IS_ERR(dart->regs)) return PTR_ERR(dart->regs); dart->irq = platform_get_irq(pdev, 0); if (dart->irq < 0) return -ENODEV; ret = devm_clk_bulk_get_all(dev, &dart->clks); if (ret < 0) return ret; dart->num_clks = ret; ret = clk_bulk_prepare_enable(dart->num_clks, dart->clks); if (ret) return ret; ret = apple_dart_hw_reset(dart); if (ret) goto err_clk_disable; dart_params[0] = readl(dart->regs + DART_PARAMS1); dart_params[1] = readl(dart->regs + DART_PARAMS2); dart->pgsize = 1 << FIELD_GET(DART_PARAMS_PAGE_SHIFT, dart_params[0]); dart->supports_bypass = dart_params[1] & DART_PARAMS_BYPASS_SUPPORT; dart->force_bypass = dart->pgsize > PAGE_SIZE; ret = request_irq(dart->irq, apple_dart_irq, IRQF_SHARED, "apple-dart fault handler", dart); if (ret) goto err_clk_disable; platform_set_drvdata(pdev, dart); ret = apple_dart_set_bus_ops(&apple_dart_iommu_ops); if (ret) goto err_free_irq; ret = iommu_device_sysfs_add(&dart->iommu, dev, NULL, "apple-dart.%s", dev_name(&pdev->dev)); if (ret) goto err_remove_bus_ops; ret = iommu_device_register(&dart->iommu, &apple_dart_iommu_ops, dev); if (ret) goto err_sysfs_remove; dev_info( &pdev->dev, "DART [pagesize %x, bypass support: %d, bypass forced: %d] initialized\n", dart->pgsize, dart->supports_bypass, dart->force_bypass); return 0; err_sysfs_remove: iommu_device_sysfs_remove(&dart->iommu); err_remove_bus_ops: apple_dart_set_bus_ops(NULL); err_free_irq: free_irq(dart->irq, dart); err_clk_disable: clk_bulk_disable_unprepare(dart->num_clks, dart->clks); return ret; } static int apple_dart_remove(struct platform_device *pdev) { struct apple_dart *dart = platform_get_drvdata(pdev); apple_dart_hw_reset(dart); free_irq(dart->irq, dart); apple_dart_set_bus_ops(NULL); iommu_device_unregister(&dart->iommu); iommu_device_sysfs_remove(&dart->iommu); clk_bulk_disable_unprepare(dart->num_clks, dart->clks); return 0; } static const struct of_device_id apple_dart_of_match[] = { { .compatible = "apple,t8103-dart", .data = NULL }, {}, }; MODULE_DEVICE_TABLE(of, apple_dart_of_match); static struct platform_driver apple_dart_driver = { .driver = { .name = "apple-dart", .of_match_table = apple_dart_of_match, .suppress_bind_attrs = true, }, .probe = apple_dart_probe, .remove = apple_dart_remove, }; module_platform_driver(apple_dart_driver); MODULE_DESCRIPTION("IOMMU API for Apple's DART"); MODULE_AUTHOR("Sven Peter "); MODULE_LICENSE("GPL v2");