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Diffstat (limited to '')
| -rw-r--r-- | drivers/iommu/apple-dart.c | 1064 |
1 files changed, 1064 insertions, 0 deletions
diff --git a/drivers/iommu/apple-dart.c b/drivers/iommu/apple-dart.c new file mode 100644 index 000000000..06ca73bdd --- /dev/null +++ b/drivers/iommu/apple-dart.c @@ -0,0 +1,1064 @@ +// 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 <linux/atomic.h> +#include <linux/bitfield.h> +#include <linux/clk.h> +#include <linux/dev_printk.h> +#include <linux/dma-mapping.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/io-pgtable.h> +#include <linux/iommu.h> +#include <linux/iopoll.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_iommu.h> +#include <linux/of_platform.h> +#include <linux/pci.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/swab.h> +#include <linux/types.h> + +#include "dma-iommu.h" + +#define DART_MAX_STREAMS 256 +#define DART_MAX_TTBR 4 +#define MAX_DARTS_PER_DEVICE 2 + + +#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 + +struct apple_dart_hw { + u32 oas; + enum io_pgtable_fmt fmt; + + int max_sid_count; +}; + +/* + * Private structure associated with each DART device. + * + * @dev: device struct + * @hw: SoC-specific hardware data + * @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; + const struct apple_dart_hw *hw; + + void __iomem *regs; + + int irq; + struct clk_bulk_data *clks; + int num_clks; + + spinlock_t lock; + + u32 pgsize; + u32 num_streams; + u32 supports_bypass : 1; + u32 force_bypass : 1; + + struct iommu_group *sid2group[DART_MAX_STREAMS]; + struct iommu_device iommu; + + u32 save_tcr[DART_MAX_STREAMS]; + u32 save_ttbr[DART_MAX_STREAMS][DART_MAX_TTBR]; +}; + +/* + * 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; + DECLARE_BITMAP(sidmap, DART_MAX_STREAMS); +}; +struct apple_dart_atomic_stream_map { + struct apple_dart *dart; + atomic_long_t sidmap[BITS_TO_LONGS(DART_MAX_STREAMS)]; +}; + +/* + * 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) +{ + struct apple_dart *dart = stream_map->dart; + int sid; + + for_each_set_bit(sid, stream_map->sidmap, dart->num_streams) + writel(DART_TCR_TRANSLATE_ENABLE, + dart->regs + DART_TCR(sid)); +} + +static void apple_dart_hw_disable_dma(struct apple_dart_stream_map *stream_map) +{ + struct apple_dart *dart = stream_map->dart; + int sid; + + for_each_set_bit(sid, stream_map->sidmap, dart->num_streams) + writel(0, dart->regs + DART_TCR(sid)); +} + +static void +apple_dart_hw_enable_bypass(struct apple_dart_stream_map *stream_map) +{ + struct apple_dart *dart = stream_map->dart; + int sid; + + WARN_ON(!stream_map->dart->supports_bypass); + for_each_set_bit(sid, stream_map->sidmap, dart->num_streams) + writel(DART_TCR_BYPASS0_ENABLE | DART_TCR_BYPASS1_ENABLE, + 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) +{ + struct apple_dart *dart = stream_map->dart; + int sid; + + WARN_ON(paddr & ((1 << DART_TTBR_SHIFT) - 1)); + for_each_set_bit(sid, stream_map->sidmap, dart->num_streams) + writel(DART_TTBR_VALID | (paddr >> DART_TTBR_SHIFT), + dart->regs + DART_TTBR(sid, idx)); +} + +static void apple_dart_hw_clear_ttbr(struct apple_dart_stream_map *stream_map, + u8 idx) +{ + struct apple_dart *dart = stream_map->dart; + int sid; + + for_each_set_bit(sid, stream_map->sidmap, dart->num_streams) + writel(0, 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[0], 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[0]); + 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; + int i; + + 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; + bitmap_zero(stream_map.sidmap, DART_MAX_STREAMS); + bitmap_set(stream_map.sidmap, 0, dart->num_streams); + 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 */ + for (i = 0; i < BITS_TO_U32(dart->num_streams); i++) + writel(U32_MAX, dart->regs + DART_STREAMS_ENABLE + 4 * i); + + /* 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, j; + 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; + + for (j = 0; j < BITS_TO_LONGS(stream_map.dart->num_streams); j++) + stream_map.sidmap[j] = atomic_long_read(&domain_stream_map->sidmap[j]); + + 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, j; + + 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; + for (j = 0; j < BITS_TO_LONGS(dart->num_streams); j++) + atomic_long_set(&dart_domain->stream_maps[i].sidmap[j], + cfg->stream_maps[i].sidmap[j]); + } + + pgtbl_cfg = (struct io_pgtable_cfg){ + .pgsize_bitmap = dart->pgsize, + .ias = 32, + .oas = dart->hw->oas, + .coherent_walk = 1, + .iommu_dev = dart->dev, + }; + + dart_domain->pgtbl_ops = + alloc_io_pgtable_ops(dart->hw->fmt, &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, j; + + 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; + for (j = 0; j < BITS_TO_LONGS(domain_maps[i].dart->num_streams); j++) { + if (add_streams) + atomic_long_or(master_maps[i].sidmap[j], + &domain_maps[i].sidmap[j]); + else + atomic_long_and(~master_maps[i].sidmap[j], + &domain_maps[i].sidmap[j]); + } + } + + 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); + + 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) { + set_bit(sid, cfg->stream_maps[i].sidmap); + return 0; + } + } + for (i = 0; i < MAX_DARTS_PER_DEVICE; ++i) { + if (!cfg->stream_maps[i].dart) { + cfg->stream_maps[i].dart = dart; + set_bit(sid, cfg->stream_maps[i].sidmap); + 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, stream_map->dart->num_streams) + stream_map->dart->sid2group[sid] = NULL; + + kfree(iommu_data); + mutex_unlock(&apple_dart_groups_lock); +} + +static int apple_dart_merge_master_cfg(struct apple_dart_master_cfg *dst, + struct apple_dart_master_cfg *src) +{ + /* + * We know that this function is only called for groups returned from + * pci_device_group and that all Apple Silicon platforms never spread + * PCIe devices from the same bus across multiple DARTs such that we can + * just assume that both src and dst only have the same single DART. + */ + if (src->stream_maps[1].dart) + return -EINVAL; + if (dst->stream_maps[1].dart) + return -EINVAL; + if (src->stream_maps[0].dart != dst->stream_maps[0].dart) + return -EINVAL; + + bitmap_or(dst->stream_maps[0].sidmap, + dst->stream_maps[0].sidmap, + src->stream_maps[0].sidmap, + dst->stream_maps[0].dart->num_streams); + return 0; +} + +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, stream_map->dart->num_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 = iommu_group_get_iommudata(group); + if (group_master_cfg) { + int ret; + + ret = apple_dart_merge_master_cfg(group_master_cfg, cfg); + if (ret) { + dev_err(dev, "Failed to merge DART IOMMU grups.\n"); + iommu_group_put(group); + res = ERR_PTR(ret); + goto out; + } + } else { + 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, stream_map->dart->num_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, GFP_KERNEL); + 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, + .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, + .pgsize_bitmap = -1UL, /* Restricted during dart probe */ + .owner = THIS_MODULE, + .default_domain_ops = &(const struct iommu_domain_ops) { + .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, + .free = apple_dart_domain_free, + } +}; + +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_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; + dart->hw = of_device_get_match_data(dev); + spin_lock_init(&dart->lock); + + dart->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res); + if (IS_ERR(dart->regs)) + return PTR_ERR(dart->regs); + + if (resource_size(res) < 0x4000) { + dev_err(dev, "MMIO region too small (%pr)\n", res); + return -EINVAL; + } + + 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; + + 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->num_streams = dart->hw->max_sid_count; + + if (dart->num_streams > DART_MAX_STREAMS) { + dev_err(&pdev->dev, "Too many streams (%d > %d)\n", + dart->num_streams, DART_MAX_STREAMS); + ret = -EINVAL; + goto err_clk_disable; + } + + dart->force_bypass = dart->pgsize > PAGE_SIZE; + + ret = apple_dart_hw_reset(dart); + if (ret) + goto err_clk_disable; + + 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 = iommu_device_sysfs_add(&dart->iommu, dev, NULL, "apple-dart.%s", + dev_name(&pdev->dev)); + if (ret) + goto err_free_irq; + + ret = iommu_device_register(&dart->iommu, &apple_dart_iommu_ops, dev); + if (ret) + goto err_sysfs_remove; + + dev_info( + &pdev->dev, + "DART [pagesize %x, %d streams, bypass support: %d, bypass forced: %d] initialized\n", + dart->pgsize, dart->num_streams, dart->supports_bypass, dart->force_bypass); + return 0; + +err_sysfs_remove: + iommu_device_sysfs_remove(&dart->iommu); +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); + + 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 apple_dart_hw apple_dart_hw_t8103 = { + .oas = 36, + .fmt = APPLE_DART, + .max_sid_count = 16, +}; +static const struct apple_dart_hw apple_dart_hw_t6000 = { + .oas = 42, + .fmt = APPLE_DART2, + .max_sid_count = 16, +}; + +static __maybe_unused int apple_dart_suspend(struct device *dev) +{ + struct apple_dart *dart = dev_get_drvdata(dev); + unsigned int sid, idx; + + for (sid = 0; sid < dart->num_streams; sid++) { + dart->save_tcr[sid] = readl_relaxed(dart->regs + DART_TCR(sid)); + for (idx = 0; idx < DART_MAX_TTBR; idx++) + dart->save_ttbr[sid][idx] = + readl(dart->regs + DART_TTBR(sid, idx)); + } + + return 0; +} + +static __maybe_unused int apple_dart_resume(struct device *dev) +{ + struct apple_dart *dart = dev_get_drvdata(dev); + unsigned int sid, idx; + int ret; + + ret = apple_dart_hw_reset(dart); + if (ret) { + dev_err(dev, "Failed to reset DART on resume\n"); + return ret; + } + + for (sid = 0; sid < dart->num_streams; sid++) { + for (idx = 0; idx < DART_MAX_TTBR; idx++) + writel(dart->save_ttbr[sid][idx], + dart->regs + DART_TTBR(sid, idx)); + writel(dart->save_tcr[sid], dart->regs + DART_TCR(sid)); + } + + return 0; +} + +DEFINE_SIMPLE_DEV_PM_OPS(apple_dart_pm_ops, apple_dart_suspend, apple_dart_resume); + +static const struct of_device_id apple_dart_of_match[] = { + { .compatible = "apple,t8103-dart", .data = &apple_dart_hw_t8103 }, + { .compatible = "apple,t6000-dart", .data = &apple_dart_hw_t6000 }, + {}, +}; +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, + .pm = pm_sleep_ptr(&apple_dart_pm_ops), + }, + .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 <sven@svenpeter.dev>"); +MODULE_LICENSE("GPL v2"); |