/* * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include <asm/cacheflush.h> #include <asm/pgtable.h> #include <linux/compiler.h> #include <linux/delay.h> #include <linux/device.h> #include <linux/errno.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/iommu.h> #include <linux/jiffies.h> #include <linux/list.h> #include <linux/mm.h> #include <linux/module.h> #include <linux/of.h> #include <linux/of_platform.h> #include <linux/platform_device.h> #include <linux/slab.h> #include <linux/spinlock.h> /** MMU register offsets */ #define RK_MMU_DTE_ADDR 0x00 /* Directory table address */ #define RK_MMU_STATUS 0x04 #define RK_MMU_COMMAND 0x08 #define RK_MMU_PAGE_FAULT_ADDR 0x0C /* IOVA of last page fault */ #define RK_MMU_ZAP_ONE_LINE 0x10 /* Shootdown one IOTLB entry */ #define RK_MMU_INT_RAWSTAT 0x14 /* IRQ status ignoring mask */ #define RK_MMU_INT_CLEAR 0x18 /* Acknowledge and re-arm irq */ #define RK_MMU_INT_MASK 0x1C /* IRQ enable */ #define RK_MMU_INT_STATUS 0x20 /* IRQ status after masking */ #define RK_MMU_AUTO_GATING 0x24 #define DTE_ADDR_DUMMY 0xCAFEBABE #define FORCE_RESET_TIMEOUT 100 /* ms */ /* RK_MMU_STATUS fields */ #define RK_MMU_STATUS_PAGING_ENABLED BIT(0) #define RK_MMU_STATUS_PAGE_FAULT_ACTIVE BIT(1) #define RK_MMU_STATUS_STALL_ACTIVE BIT(2) #define RK_MMU_STATUS_IDLE BIT(3) #define RK_MMU_STATUS_REPLAY_BUFFER_EMPTY BIT(4) #define RK_MMU_STATUS_PAGE_FAULT_IS_WRITE BIT(5) #define RK_MMU_STATUS_STALL_NOT_ACTIVE BIT(31) /* RK_MMU_COMMAND command values */ #define RK_MMU_CMD_ENABLE_PAGING 0 /* Enable memory translation */ #define RK_MMU_CMD_DISABLE_PAGING 1 /* Disable memory translation */ #define RK_MMU_CMD_ENABLE_STALL 2 /* Stall paging to allow other cmds */ #define RK_MMU_CMD_DISABLE_STALL 3 /* Stop stall re-enables paging */ #define RK_MMU_CMD_ZAP_CACHE 4 /* Shoot down entire IOTLB */ #define RK_MMU_CMD_PAGE_FAULT_DONE 5 /* Clear page fault */ #define RK_MMU_CMD_FORCE_RESET 6 /* Reset all registers */ /* RK_MMU_INT_* register fields */ #define RK_MMU_IRQ_PAGE_FAULT 0x01 /* page fault */ #define RK_MMU_IRQ_BUS_ERROR 0x02 /* bus read error */ #define RK_MMU_IRQ_MASK (RK_MMU_IRQ_PAGE_FAULT | RK_MMU_IRQ_BUS_ERROR) #define NUM_DT_ENTRIES 1024 #define NUM_PT_ENTRIES 1024 #define SPAGE_ORDER 12 #define SPAGE_SIZE (1 << SPAGE_ORDER) /* * Support mapping any size that fits in one page table: * 4 KiB to 4 MiB */ #define RK_IOMMU_PGSIZE_BITMAP 0x007ff000 #define IOMMU_REG_POLL_COUNT_FAST 1000 struct rk_iommu_domain { struct list_head iommus; u32 *dt; /* page directory table */ spinlock_t iommus_lock; /* lock for iommus list */ spinlock_t dt_lock; /* lock for modifying page directory table */ struct iommu_domain domain; }; struct rk_iommu { struct device *dev; void __iomem *base; int irq; struct list_head node; /* entry in rk_iommu_domain.iommus */ struct iommu_domain *domain; /* domain to which iommu is attached */ }; static inline void rk_table_flush(u32 *va, unsigned int count) { phys_addr_t pa_start = virt_to_phys(va); phys_addr_t pa_end = virt_to_phys(va + count); size_t size = pa_end - pa_start; __cpuc_flush_dcache_area(va, size); outer_flush_range(pa_start, pa_end); } static struct rk_iommu_domain *to_rk_domain(struct iommu_domain *dom) { return container_of(dom, struct rk_iommu_domain, domain); } /** * Inspired by _wait_for in intel_drv.h * This is NOT safe for use in interrupt context. * * Note that it's important that we check the condition again after having * timed out, since the timeout could be due to preemption or similar and * we've never had a chance to check the condition before the timeout. */ #define rk_wait_for(COND, MS) ({ \ unsigned long timeout__ = jiffies + msecs_to_jiffies(MS) + 1; \ int ret__ = 0; \ while (!(COND)) { \ if (time_after(jiffies, timeout__)) { \ ret__ = (COND) ? 0 : -ETIMEDOUT; \ break; \ } \ usleep_range(50, 100); \ } \ ret__; \ }) /* * The Rockchip rk3288 iommu uses a 2-level page table. * The first level is the "Directory Table" (DT). * The DT consists of 1024 4-byte Directory Table Entries (DTEs), each pointing * to a "Page Table". * The second level is the 1024 Page Tables (PT). * Each PT consists of 1024 4-byte Page Table Entries (PTEs), each pointing to * a 4 KB page of physical memory. * * The DT and each PT fits in a single 4 KB page (4-bytes * 1024 entries). * Each iommu device has a MMU_DTE_ADDR register that contains the physical * address of the start of the DT page. * * The structure of the page table is as follows: * * DT * MMU_DTE_ADDR -> +-----+ * | | * +-----+ PT * | DTE | -> +-----+ * +-----+ | | Memory * | | +-----+ Page * | | | PTE | -> +-----+ * +-----+ +-----+ | | * | | | | * | | | | * +-----+ | | * | | * | | * +-----+ */ /* * Each DTE has a PT address and a valid bit: * +---------------------+-----------+-+ * | PT address | Reserved |V| * +---------------------+-----------+-+ * 31:12 - PT address (PTs always starts on a 4 KB boundary) * 11: 1 - Reserved * 0 - 1 if PT @ PT address is valid */ #define RK_DTE_PT_ADDRESS_MASK 0xfffff000 #define RK_DTE_PT_VALID BIT(0) static inline phys_addr_t rk_dte_pt_address(u32 dte) { return (phys_addr_t)dte & RK_DTE_PT_ADDRESS_MASK; } static inline bool rk_dte_is_pt_valid(u32 dte) { return dte & RK_DTE_PT_VALID; } static u32 rk_mk_dte(u32 *pt) { phys_addr_t pt_phys = virt_to_phys(pt); return (pt_phys & RK_DTE_PT_ADDRESS_MASK) | RK_DTE_PT_VALID; } /* * Each PTE has a Page address, some flags and a valid bit: * +---------------------+---+-------+-+ * | Page address |Rsv| Flags |V| * +---------------------+---+-------+-+ * 31:12 - Page address (Pages always start on a 4 KB boundary) * 11: 9 - Reserved * 8: 1 - Flags * 8 - Read allocate - allocate cache space on read misses * 7 - Read cache - enable cache & prefetch of data * 6 - Write buffer - enable delaying writes on their way to memory * 5 - Write allocate - allocate cache space on write misses * 4 - Write cache - different writes can be merged together * 3 - Override cache attributes * if 1, bits 4-8 control cache attributes * if 0, the system bus defaults are used * 2 - Writable * 1 - Readable * 0 - 1 if Page @ Page address is valid */ #define RK_PTE_PAGE_ADDRESS_MASK 0xfffff000 #define RK_PTE_PAGE_FLAGS_MASK 0x000001fe #define RK_PTE_PAGE_WRITABLE BIT(2) #define RK_PTE_PAGE_READABLE BIT(1) #define RK_PTE_PAGE_VALID BIT(0) static inline phys_addr_t rk_pte_page_address(u32 pte) { return (phys_addr_t)pte & RK_PTE_PAGE_ADDRESS_MASK; } static inline bool rk_pte_is_page_valid(u32 pte) { return pte & RK_PTE_PAGE_VALID; } /* TODO: set cache flags per prot IOMMU_CACHE */ static u32 rk_mk_pte(phys_addr_t page, int prot) { u32 flags = 0; flags |= (prot & IOMMU_READ) ? RK_PTE_PAGE_READABLE : 0; flags |= (prot & IOMMU_WRITE) ? RK_PTE_PAGE_WRITABLE : 0; page &= RK_PTE_PAGE_ADDRESS_MASK; return page | flags | RK_PTE_PAGE_VALID; } static u32 rk_mk_pte_invalid(u32 pte) { return pte & ~RK_PTE_PAGE_VALID; } /* * rk3288 iova (IOMMU Virtual Address) format * 31 22.21 12.11 0 * +-----------+-----------+-------------+ * | DTE index | PTE index | Page offset | * +-----------+-----------+-------------+ * 31:22 - DTE index - index of DTE in DT * 21:12 - PTE index - index of PTE in PT @ DTE.pt_address * 11: 0 - Page offset - offset into page @ PTE.page_address */ #define RK_IOVA_DTE_MASK 0xffc00000 #define RK_IOVA_DTE_SHIFT 22 #define RK_IOVA_PTE_MASK 0x003ff000 #define RK_IOVA_PTE_SHIFT 12 #define RK_IOVA_PAGE_MASK 0x00000fff #define RK_IOVA_PAGE_SHIFT 0 static u32 rk_iova_dte_index(dma_addr_t iova) { return (u32)(iova & RK_IOVA_DTE_MASK) >> RK_IOVA_DTE_SHIFT; } static u32 rk_iova_pte_index(dma_addr_t iova) { return (u32)(iova & RK_IOVA_PTE_MASK) >> RK_IOVA_PTE_SHIFT; } static u32 rk_iova_page_offset(dma_addr_t iova) { return (u32)(iova & RK_IOVA_PAGE_MASK) >> RK_IOVA_PAGE_SHIFT; } static u32 rk_iommu_read(struct rk_iommu *iommu, u32 offset) { return readl(iommu->base + offset); } static void rk_iommu_write(struct rk_iommu *iommu, u32 offset, u32 value) { writel(value, iommu->base + offset); } static void rk_iommu_command(struct rk_iommu *iommu, u32 command) { writel(command, iommu->base + RK_MMU_COMMAND); } static void rk_iommu_zap_lines(struct rk_iommu *iommu, dma_addr_t iova, size_t size) { dma_addr_t iova_end = iova + size; /* * TODO(djkurtz): Figure out when it is more efficient to shootdown the * entire iotlb rather than iterate over individual iovas. */ for (; iova < iova_end; iova += SPAGE_SIZE) rk_iommu_write(iommu, RK_MMU_ZAP_ONE_LINE, iova); } static bool rk_iommu_is_stall_active(struct rk_iommu *iommu) { return rk_iommu_read(iommu, RK_MMU_STATUS) & RK_MMU_STATUS_STALL_ACTIVE; } static bool rk_iommu_is_paging_enabled(struct rk_iommu *iommu) { return rk_iommu_read(iommu, RK_MMU_STATUS) & RK_MMU_STATUS_PAGING_ENABLED; } static int rk_iommu_enable_stall(struct rk_iommu *iommu) { int ret; if (rk_iommu_is_stall_active(iommu)) return 0; /* Stall can only be enabled if paging is enabled */ if (!rk_iommu_is_paging_enabled(iommu)) return 0; rk_iommu_command(iommu, RK_MMU_CMD_ENABLE_STALL); ret = rk_wait_for(rk_iommu_is_stall_active(iommu), 1); if (ret) dev_err(iommu->dev, "Enable stall request timed out, status: %#08x\n", rk_iommu_read(iommu, RK_MMU_STATUS)); return ret; } static int rk_iommu_disable_stall(struct rk_iommu *iommu) { int ret; if (!rk_iommu_is_stall_active(iommu)) return 0; rk_iommu_command(iommu, RK_MMU_CMD_DISABLE_STALL); ret = rk_wait_for(!rk_iommu_is_stall_active(iommu), 1); if (ret) dev_err(iommu->dev, "Disable stall request timed out, status: %#08x\n", rk_iommu_read(iommu, RK_MMU_STATUS)); return ret; } static int rk_iommu_enable_paging(struct rk_iommu *iommu) { int ret; if (rk_iommu_is_paging_enabled(iommu)) return 0; rk_iommu_command(iommu, RK_MMU_CMD_ENABLE_PAGING); ret = rk_wait_for(rk_iommu_is_paging_enabled(iommu), 1); if (ret) dev_err(iommu->dev, "Enable paging request timed out, status: %#08x\n", rk_iommu_read(iommu, RK_MMU_STATUS)); return ret; } static int rk_iommu_disable_paging(struct rk_iommu *iommu) { int ret; if (!rk_iommu_is_paging_enabled(iommu)) return 0; rk_iommu_command(iommu, RK_MMU_CMD_DISABLE_PAGING); ret = rk_wait_for(!rk_iommu_is_paging_enabled(iommu), 1); if (ret) dev_err(iommu->dev, "Disable paging request timed out, status: %#08x\n", rk_iommu_read(iommu, RK_MMU_STATUS)); return ret; } static int rk_iommu_force_reset(struct rk_iommu *iommu) { int ret; u32 dte_addr; /* * Check if register DTE_ADDR is working by writing DTE_ADDR_DUMMY * and verifying that upper 5 nybbles are read back. */ rk_iommu_write(iommu, RK_MMU_DTE_ADDR, DTE_ADDR_DUMMY); dte_addr = rk_iommu_read(iommu, RK_MMU_DTE_ADDR); if (dte_addr != (DTE_ADDR_DUMMY & RK_DTE_PT_ADDRESS_MASK)) { dev_err(iommu->dev, "Error during raw reset. MMU_DTE_ADDR is not functioning\n"); return -EFAULT; } rk_iommu_command(iommu, RK_MMU_CMD_FORCE_RESET); ret = rk_wait_for(rk_iommu_read(iommu, RK_MMU_DTE_ADDR) == 0x00000000, FORCE_RESET_TIMEOUT); if (ret) dev_err(iommu->dev, "FORCE_RESET command timed out\n"); return ret; } static void log_iova(struct rk_iommu *iommu, dma_addr_t iova) { u32 dte_index, pte_index, page_offset; u32 mmu_dte_addr; phys_addr_t mmu_dte_addr_phys, dte_addr_phys; u32 *dte_addr; u32 dte; phys_addr_t pte_addr_phys = 0; u32 *pte_addr = NULL; u32 pte = 0; phys_addr_t page_addr_phys = 0; u32 page_flags = 0; dte_index = rk_iova_dte_index(iova); pte_index = rk_iova_pte_index(iova); page_offset = rk_iova_page_offset(iova); mmu_dte_addr = rk_iommu_read(iommu, RK_MMU_DTE_ADDR); mmu_dte_addr_phys = (phys_addr_t)mmu_dte_addr; dte_addr_phys = mmu_dte_addr_phys + (4 * dte_index); dte_addr = phys_to_virt(dte_addr_phys); dte = *dte_addr; if (!rk_dte_is_pt_valid(dte)) goto print_it; pte_addr_phys = rk_dte_pt_address(dte) + (pte_index * 4); pte_addr = phys_to_virt(pte_addr_phys); pte = *pte_addr; if (!rk_pte_is_page_valid(pte)) goto print_it; page_addr_phys = rk_pte_page_address(pte) + page_offset; page_flags = pte & RK_PTE_PAGE_FLAGS_MASK; print_it: dev_err(iommu->dev, "iova = %pad: dte_index: %#03x pte_index: %#03x page_offset: %#03x\n", &iova, dte_index, pte_index, page_offset); dev_err(iommu->dev, "mmu_dte_addr: %pa dte@%pa: %#08x valid: %u pte@%pa: %#08x valid: %u page@%pa flags: %#03x\n", &mmu_dte_addr_phys, &dte_addr_phys, dte, rk_dte_is_pt_valid(dte), &pte_addr_phys, pte, rk_pte_is_page_valid(pte), &page_addr_phys, page_flags); } static irqreturn_t rk_iommu_irq(int irq, void *dev_id) { struct rk_iommu *iommu = dev_id; u32 status; u32 int_status; dma_addr_t iova; int_status = rk_iommu_read(iommu, RK_MMU_INT_STATUS); if (int_status == 0) return IRQ_NONE; iova = rk_iommu_read(iommu, RK_MMU_PAGE_FAULT_ADDR); if (int_status & RK_MMU_IRQ_PAGE_FAULT) { int flags; status = rk_iommu_read(iommu, RK_MMU_STATUS); flags = (status & RK_MMU_STATUS_PAGE_FAULT_IS_WRITE) ? IOMMU_FAULT_WRITE : IOMMU_FAULT_READ; dev_err(iommu->dev, "Page fault at %pad of type %s\n", &iova, (flags == IOMMU_FAULT_WRITE) ? "write" : "read"); log_iova(iommu, iova); /* * Report page fault to any installed handlers. * Ignore the return code, though, since we always zap cache * and clear the page fault anyway. */ if (iommu->domain) report_iommu_fault(iommu->domain, iommu->dev, iova, flags); else dev_err(iommu->dev, "Page fault while iommu not attached to domain?\n"); rk_iommu_command(iommu, RK_MMU_CMD_ZAP_CACHE); rk_iommu_command(iommu, RK_MMU_CMD_PAGE_FAULT_DONE); } if (int_status & RK_MMU_IRQ_BUS_ERROR) dev_err(iommu->dev, "BUS_ERROR occurred at %pad\n", &iova); if (int_status & ~RK_MMU_IRQ_MASK) dev_err(iommu->dev, "unexpected int_status: %#08x\n", int_status); rk_iommu_write(iommu, RK_MMU_INT_CLEAR, int_status); return IRQ_HANDLED; } static phys_addr_t rk_iommu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova) { struct rk_iommu_domain *rk_domain = to_rk_domain(domain); unsigned long flags; phys_addr_t pt_phys, phys = 0; u32 dte, pte; u32 *page_table; spin_lock_irqsave(&rk_domain->dt_lock, flags); dte = rk_domain->dt[rk_iova_dte_index(iova)]; if (!rk_dte_is_pt_valid(dte)) goto out; pt_phys = rk_dte_pt_address(dte); page_table = (u32 *)phys_to_virt(pt_phys); pte = page_table[rk_iova_pte_index(iova)]; if (!rk_pte_is_page_valid(pte)) goto out; phys = rk_pte_page_address(pte) + rk_iova_page_offset(iova); out: spin_unlock_irqrestore(&rk_domain->dt_lock, flags); return phys; } static void rk_iommu_zap_iova(struct rk_iommu_domain *rk_domain, dma_addr_t iova, size_t size) { struct list_head *pos; unsigned long flags; /* shootdown these iova from all iommus using this domain */ spin_lock_irqsave(&rk_domain->iommus_lock, flags); list_for_each(pos, &rk_domain->iommus) { struct rk_iommu *iommu; iommu = list_entry(pos, struct rk_iommu, node); rk_iommu_zap_lines(iommu, iova, size); } spin_unlock_irqrestore(&rk_domain->iommus_lock, flags); } static void rk_iommu_zap_iova_first_last(struct rk_iommu_domain *rk_domain, dma_addr_t iova, size_t size) { rk_iommu_zap_iova(rk_domain, iova, SPAGE_SIZE); if (size > SPAGE_SIZE) rk_iommu_zap_iova(rk_domain, iova + size - SPAGE_SIZE, SPAGE_SIZE); } static u32 *rk_dte_get_page_table(struct rk_iommu_domain *rk_domain, dma_addr_t iova) { u32 *page_table, *dte_addr; u32 dte; phys_addr_t pt_phys; assert_spin_locked(&rk_domain->dt_lock); dte_addr = &rk_domain->dt[rk_iova_dte_index(iova)]; dte = *dte_addr; if (rk_dte_is_pt_valid(dte)) goto done; page_table = (u32 *)get_zeroed_page(GFP_ATOMIC | GFP_DMA32); if (!page_table) return ERR_PTR(-ENOMEM); dte = rk_mk_dte(page_table); *dte_addr = dte; rk_table_flush(page_table, NUM_PT_ENTRIES); rk_table_flush(dte_addr, 1); done: pt_phys = rk_dte_pt_address(dte); return (u32 *)phys_to_virt(pt_phys); } static size_t rk_iommu_unmap_iova(struct rk_iommu_domain *rk_domain, u32 *pte_addr, dma_addr_t iova, size_t size) { unsigned int pte_count; unsigned int pte_total = size / SPAGE_SIZE; assert_spin_locked(&rk_domain->dt_lock); for (pte_count = 0; pte_count < pte_total; pte_count++) { u32 pte = pte_addr[pte_count]; if (!rk_pte_is_page_valid(pte)) break; pte_addr[pte_count] = rk_mk_pte_invalid(pte); } rk_table_flush(pte_addr, pte_count); return pte_count * SPAGE_SIZE; } static int rk_iommu_map_iova(struct rk_iommu_domain *rk_domain, u32 *pte_addr, dma_addr_t iova, phys_addr_t paddr, size_t size, int prot) { unsigned int pte_count; unsigned int pte_total = size / SPAGE_SIZE; phys_addr_t page_phys; assert_spin_locked(&rk_domain->dt_lock); for (pte_count = 0; pte_count < pte_total; pte_count++) { u32 pte = pte_addr[pte_count]; if (rk_pte_is_page_valid(pte)) goto unwind; pte_addr[pte_count] = rk_mk_pte(paddr, prot); paddr += SPAGE_SIZE; } rk_table_flush(pte_addr, pte_count); /* * Zap the first and last iova to evict from iotlb any previously * mapped cachelines holding stale values for its dte and pte. * We only zap the first and last iova, since only they could have * dte or pte shared with an existing mapping. */ rk_iommu_zap_iova_first_last(rk_domain, iova, size); return 0; unwind: /* Unmap the range of iovas that we just mapped */ rk_iommu_unmap_iova(rk_domain, pte_addr, iova, pte_count * SPAGE_SIZE); iova += pte_count * SPAGE_SIZE; page_phys = rk_pte_page_address(pte_addr[pte_count]); pr_err("iova: %pad already mapped to %pa cannot remap to phys: %pa prot: %#x\n", &iova, &page_phys, &paddr, prot); return -EADDRINUSE; } static int rk_iommu_map(struct iommu_domain *domain, unsigned long _iova, phys_addr_t paddr, size_t size, int prot) { struct rk_iommu_domain *rk_domain = to_rk_domain(domain); unsigned long flags; dma_addr_t iova = (dma_addr_t)_iova; u32 *page_table, *pte_addr; int ret; spin_lock_irqsave(&rk_domain->dt_lock, flags); /* * pgsize_bitmap specifies iova sizes that fit in one page table * (1024 4-KiB pages = 4 MiB). * So, size will always be 4096 <= size <= 4194304. * Since iommu_map() guarantees that both iova and size will be * aligned, we will always only be mapping from a single dte here. */ page_table = rk_dte_get_page_table(rk_domain, iova); if (IS_ERR(page_table)) { spin_unlock_irqrestore(&rk_domain->dt_lock, flags); return PTR_ERR(page_table); } pte_addr = &page_table[rk_iova_pte_index(iova)]; ret = rk_iommu_map_iova(rk_domain, pte_addr, iova, paddr, size, prot); spin_unlock_irqrestore(&rk_domain->dt_lock, flags); return ret; } static size_t rk_iommu_unmap(struct iommu_domain *domain, unsigned long _iova, size_t size) { struct rk_iommu_domain *rk_domain = to_rk_domain(domain); unsigned long flags; dma_addr_t iova = (dma_addr_t)_iova; phys_addr_t pt_phys; u32 dte; u32 *pte_addr; size_t unmap_size; spin_lock_irqsave(&rk_domain->dt_lock, flags); /* * pgsize_bitmap specifies iova sizes that fit in one page table * (1024 4-KiB pages = 4 MiB). * So, size will always be 4096 <= size <= 4194304. * Since iommu_unmap() guarantees that both iova and size will be * aligned, we will always only be unmapping from a single dte here. */ dte = rk_domain->dt[rk_iova_dte_index(iova)]; /* Just return 0 if iova is unmapped */ if (!rk_dte_is_pt_valid(dte)) { spin_unlock_irqrestore(&rk_domain->dt_lock, flags); return 0; } pt_phys = rk_dte_pt_address(dte); pte_addr = (u32 *)phys_to_virt(pt_phys) + rk_iova_pte_index(iova); unmap_size = rk_iommu_unmap_iova(rk_domain, pte_addr, iova, size); spin_unlock_irqrestore(&rk_domain->dt_lock, flags); /* Shootdown iotlb entries for iova range that was just unmapped */ rk_iommu_zap_iova(rk_domain, iova, unmap_size); return unmap_size; } static struct rk_iommu *rk_iommu_from_dev(struct device *dev) { struct iommu_group *group; struct device *iommu_dev; struct rk_iommu *rk_iommu; group = iommu_group_get(dev); if (!group) return NULL; iommu_dev = iommu_group_get_iommudata(group); rk_iommu = dev_get_drvdata(iommu_dev); iommu_group_put(group); return rk_iommu; } static int rk_iommu_attach_device(struct iommu_domain *domain, struct device *dev) { struct rk_iommu *iommu; struct rk_iommu_domain *rk_domain = to_rk_domain(domain); unsigned long flags; int ret; phys_addr_t dte_addr; /* * Allow 'virtual devices' (e.g., drm) to attach to domain. * Such a device does not belong to an iommu group. */ iommu = rk_iommu_from_dev(dev); if (!iommu) return 0; ret = rk_iommu_enable_stall(iommu); if (ret) return ret; ret = rk_iommu_force_reset(iommu); if (ret) return ret; iommu->domain = domain; ret = devm_request_irq(dev, iommu->irq, rk_iommu_irq, IRQF_SHARED, dev_name(dev), iommu); if (ret) return ret; dte_addr = virt_to_phys(rk_domain->dt); rk_iommu_write(iommu, RK_MMU_DTE_ADDR, dte_addr); rk_iommu_command(iommu, RK_MMU_CMD_ZAP_CACHE); rk_iommu_write(iommu, RK_MMU_INT_MASK, RK_MMU_IRQ_MASK); ret = rk_iommu_enable_paging(iommu); if (ret) return ret; spin_lock_irqsave(&rk_domain->iommus_lock, flags); list_add_tail(&iommu->node, &rk_domain->iommus); spin_unlock_irqrestore(&rk_domain->iommus_lock, flags); dev_dbg(dev, "Attached to iommu domain\n"); rk_iommu_disable_stall(iommu); return 0; } static void rk_iommu_detach_device(struct iommu_domain *domain, struct device *dev) { struct rk_iommu *iommu; struct rk_iommu_domain *rk_domain = to_rk_domain(domain); unsigned long flags; /* Allow 'virtual devices' (eg drm) to detach from domain */ iommu = rk_iommu_from_dev(dev); if (!iommu) return; spin_lock_irqsave(&rk_domain->iommus_lock, flags); list_del_init(&iommu->node); spin_unlock_irqrestore(&rk_domain->iommus_lock, flags); /* Ignore error while disabling, just keep going */ rk_iommu_enable_stall(iommu); rk_iommu_disable_paging(iommu); rk_iommu_write(iommu, RK_MMU_INT_MASK, 0); rk_iommu_write(iommu, RK_MMU_DTE_ADDR, 0); rk_iommu_disable_stall(iommu); devm_free_irq(dev, iommu->irq, iommu); iommu->domain = NULL; dev_dbg(dev, "Detached from iommu domain\n"); } static struct iommu_domain *rk_iommu_domain_alloc(unsigned type) { struct rk_iommu_domain *rk_domain; if (type != IOMMU_DOMAIN_UNMANAGED) return NULL; rk_domain = kzalloc(sizeof(*rk_domain), GFP_KERNEL); if (!rk_domain) return NULL; /* * rk32xx iommus use a 2 level pagetable. * Each level1 (dt) and level2 (pt) table has 1024 4-byte entries. * Allocate one 4 KiB page for each table. */ rk_domain->dt = (u32 *)get_zeroed_page(GFP_KERNEL | GFP_DMA32); if (!rk_domain->dt) goto err_dt; rk_table_flush(rk_domain->dt, NUM_DT_ENTRIES); spin_lock_init(&rk_domain->iommus_lock); spin_lock_init(&rk_domain->dt_lock); INIT_LIST_HEAD(&rk_domain->iommus); return &rk_domain->domain; err_dt: kfree(rk_domain); return NULL; } static void rk_iommu_domain_free(struct iommu_domain *domain) { struct rk_iommu_domain *rk_domain = to_rk_domain(domain); int i; WARN_ON(!list_empty(&rk_domain->iommus)); for (i = 0; i < NUM_DT_ENTRIES; i++) { u32 dte = rk_domain->dt[i]; if (rk_dte_is_pt_valid(dte)) { phys_addr_t pt_phys = rk_dte_pt_address(dte); u32 *page_table = phys_to_virt(pt_phys); free_page((unsigned long)page_table); } } free_page((unsigned long)rk_domain->dt); kfree(rk_domain); } static bool rk_iommu_is_dev_iommu_master(struct device *dev) { struct device_node *np = dev->of_node; int ret; /* * An iommu master has an iommus property containing a list of phandles * to iommu nodes, each with an #iommu-cells property with value 0. */ ret = of_count_phandle_with_args(np, "iommus", "#iommu-cells"); return (ret > 0); } static int rk_iommu_group_set_iommudata(struct iommu_group *group, struct device *dev) { struct device_node *np = dev->of_node; struct platform_device *pd; int ret; struct of_phandle_args args; /* * An iommu master has an iommus property containing a list of phandles * to iommu nodes, each with an #iommu-cells property with value 0. */ ret = of_parse_phandle_with_args(np, "iommus", "#iommu-cells", 0, &args); if (ret) { dev_err(dev, "of_parse_phandle_with_args(%s) => %d\n", np->full_name, ret); return ret; } if (args.args_count != 0) { dev_err(dev, "incorrect number of iommu params found for %s (found %d, expected 0)\n", args.np->full_name, args.args_count); return -EINVAL; } pd = of_find_device_by_node(args.np); of_node_put(args.np); if (!pd) { dev_err(dev, "iommu %s not found\n", args.np->full_name); return -EPROBE_DEFER; } /* TODO(djkurtz): handle multiple slave iommus for a single master */ iommu_group_set_iommudata(group, &pd->dev, NULL); return 0; } static int rk_iommu_add_device(struct device *dev) { struct iommu_group *group; int ret; if (!rk_iommu_is_dev_iommu_master(dev)) return -ENODEV; group = iommu_group_get(dev); if (!group) { group = iommu_group_alloc(); if (IS_ERR(group)) { dev_err(dev, "Failed to allocate IOMMU group\n"); return PTR_ERR(group); } } ret = iommu_group_add_device(group, dev); if (ret) goto err_put_group; ret = rk_iommu_group_set_iommudata(group, dev); if (ret) goto err_remove_device; iommu_group_put(group); return 0; err_remove_device: iommu_group_remove_device(dev); err_put_group: iommu_group_put(group); return ret; } static void rk_iommu_remove_device(struct device *dev) { if (!rk_iommu_is_dev_iommu_master(dev)) return; iommu_group_remove_device(dev); } static const struct iommu_ops rk_iommu_ops = { .domain_alloc = rk_iommu_domain_alloc, .domain_free = rk_iommu_domain_free, .attach_dev = rk_iommu_attach_device, .detach_dev = rk_iommu_detach_device, .map = rk_iommu_map, .unmap = rk_iommu_unmap, .add_device = rk_iommu_add_device, .remove_device = rk_iommu_remove_device, .iova_to_phys = rk_iommu_iova_to_phys, .pgsize_bitmap = RK_IOMMU_PGSIZE_BITMAP, }; static int rk_iommu_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct rk_iommu *iommu; struct resource *res; iommu = devm_kzalloc(dev, sizeof(*iommu), GFP_KERNEL); if (!iommu) return -ENOMEM; platform_set_drvdata(pdev, iommu); iommu->dev = dev; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); iommu->base = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(iommu->base)) return PTR_ERR(iommu->base); iommu->irq = platform_get_irq(pdev, 0); if (iommu->irq < 0) { dev_err(dev, "Failed to get IRQ, %d\n", iommu->irq); return -ENXIO; } return 0; } static int rk_iommu_remove(struct platform_device *pdev) { return 0; } static const struct of_device_id rk_iommu_dt_ids[] = { { .compatible = "rockchip,iommu" }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, rk_iommu_dt_ids); static struct platform_driver rk_iommu_driver = { .probe = rk_iommu_probe, .remove = rk_iommu_remove, .driver = { .name = "rk_iommu", .of_match_table = rk_iommu_dt_ids, }, }; static int __init rk_iommu_init(void) { struct device_node *np; int ret; np = of_find_matching_node(NULL, rk_iommu_dt_ids); if (!np) return 0; of_node_put(np); ret = bus_set_iommu(&platform_bus_type, &rk_iommu_ops); if (ret) return ret; return platform_driver_register(&rk_iommu_driver); } static void __exit rk_iommu_exit(void) { platform_driver_unregister(&rk_iommu_driver); } subsys_initcall(rk_iommu_init); module_exit(rk_iommu_exit); MODULE_DESCRIPTION("IOMMU API for Rockchip"); MODULE_AUTHOR("Simon Xue <xxm@rock-chips.com> and Daniel Kurtz <djkurtz@chromium.org>"); MODULE_ALIAS("platform:rockchip-iommu"); MODULE_LICENSE("GPL v2");