diff options
Diffstat (limited to 'drivers/iommu/rockchip-iommu.c')
| -rw-r--r-- | drivers/iommu/rockchip-iommu.c | 1309 |
1 files changed, 1309 insertions, 0 deletions
diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c new file mode 100644 index 000000000..140b287e8 --- /dev/null +++ b/drivers/iommu/rockchip-iommu.c @@ -0,0 +1,1309 @@ +/* + * 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 <linux/clk.h> +#include <linux/compiler.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/dma-iommu.h> +#include <linux/dma-mapping.h> +#include <linux/errno.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/iommu.h> +#include <linux/iopoll.h> +#include <linux/list.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_iommu.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.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 RK_MMU_POLL_PERIOD_US 100 +#define RK_MMU_FORCE_RESET_TIMEOUT_US 100000 +#define RK_MMU_POLL_TIMEOUT_US 1000 + +/* 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 + +struct rk_iommu_domain { + struct list_head iommus; + u32 *dt; /* page directory table */ + dma_addr_t dt_dma; + spinlock_t iommus_lock; /* lock for iommus list */ + spinlock_t dt_lock; /* lock for modifying page directory table */ + + struct iommu_domain domain; +}; + +/* list of clocks required by IOMMU */ +static const char * const rk_iommu_clocks[] = { + "aclk", "iface", +}; + +struct rk_iommu { + struct device *dev; + void __iomem **bases; + int num_mmu; + struct clk_bulk_data *clocks; + int num_clocks; + bool reset_disabled; + struct iommu_device iommu; + struct list_head node; /* entry in rk_iommu_domain.iommus */ + struct iommu_domain *domain; /* domain to which iommu is attached */ + struct iommu_group *group; +}; + +struct rk_iommudata { + struct device_link *link; /* runtime PM link from IOMMU to master */ + struct rk_iommu *iommu; +}; + +static struct device *dma_dev; + +static inline void rk_table_flush(struct rk_iommu_domain *dom, dma_addr_t dma, + unsigned int count) +{ + size_t size = count * sizeof(u32); /* count of u32 entry */ + + dma_sync_single_for_device(dma_dev, dma, size, DMA_TO_DEVICE); +} + +static struct rk_iommu_domain *to_rk_domain(struct iommu_domain *dom) +{ + return container_of(dom, struct rk_iommu_domain, domain); +} + +/* + * 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 inline u32 rk_mk_dte(dma_addr_t pt_dma) +{ + return (pt_dma & 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(void __iomem *base, u32 offset) +{ + return readl(base + offset); +} + +static void rk_iommu_write(void __iomem *base, u32 offset, u32 value) +{ + writel(value, base + offset); +} + +static void rk_iommu_command(struct rk_iommu *iommu, u32 command) +{ + int i; + + for (i = 0; i < iommu->num_mmu; i++) + writel(command, iommu->bases[i] + RK_MMU_COMMAND); +} + +static void rk_iommu_base_command(void __iomem *base, u32 command) +{ + writel(command, base + RK_MMU_COMMAND); +} +static void rk_iommu_zap_lines(struct rk_iommu *iommu, dma_addr_t iova_start, + size_t size) +{ + int i; + dma_addr_t iova_end = iova_start + size; + /* + * TODO(djkurtz): Figure out when it is more efficient to shootdown the + * entire iotlb rather than iterate over individual iovas. + */ + for (i = 0; i < iommu->num_mmu; i++) { + dma_addr_t iova; + + for (iova = iova_start; iova < iova_end; iova += SPAGE_SIZE) + rk_iommu_write(iommu->bases[i], RK_MMU_ZAP_ONE_LINE, iova); + } +} + +static bool rk_iommu_is_stall_active(struct rk_iommu *iommu) +{ + bool active = true; + int i; + + for (i = 0; i < iommu->num_mmu; i++) + active &= !!(rk_iommu_read(iommu->bases[i], RK_MMU_STATUS) & + RK_MMU_STATUS_STALL_ACTIVE); + + return active; +} + +static bool rk_iommu_is_paging_enabled(struct rk_iommu *iommu) +{ + bool enable = true; + int i; + + for (i = 0; i < iommu->num_mmu; i++) + enable &= !!(rk_iommu_read(iommu->bases[i], RK_MMU_STATUS) & + RK_MMU_STATUS_PAGING_ENABLED); + + return enable; +} + +static bool rk_iommu_is_reset_done(struct rk_iommu *iommu) +{ + bool done = true; + int i; + + for (i = 0; i < iommu->num_mmu; i++) + done &= rk_iommu_read(iommu->bases[i], RK_MMU_DTE_ADDR) == 0; + + return done; +} + +static int rk_iommu_enable_stall(struct rk_iommu *iommu) +{ + int ret, i; + bool val; + + 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 = readx_poll_timeout(rk_iommu_is_stall_active, iommu, val, + val, RK_MMU_POLL_PERIOD_US, + RK_MMU_POLL_TIMEOUT_US); + if (ret) + for (i = 0; i < iommu->num_mmu; i++) + dev_err(iommu->dev, "Enable stall request timed out, status: %#08x\n", + rk_iommu_read(iommu->bases[i], RK_MMU_STATUS)); + + return ret; +} + +static int rk_iommu_disable_stall(struct rk_iommu *iommu) +{ + int ret, i; + bool val; + + if (!rk_iommu_is_stall_active(iommu)) + return 0; + + rk_iommu_command(iommu, RK_MMU_CMD_DISABLE_STALL); + + ret = readx_poll_timeout(rk_iommu_is_stall_active, iommu, val, + !val, RK_MMU_POLL_PERIOD_US, + RK_MMU_POLL_TIMEOUT_US); + if (ret) + for (i = 0; i < iommu->num_mmu; i++) + dev_err(iommu->dev, "Disable stall request timed out, status: %#08x\n", + rk_iommu_read(iommu->bases[i], RK_MMU_STATUS)); + + return ret; +} + +static int rk_iommu_enable_paging(struct rk_iommu *iommu) +{ + int ret, i; + bool val; + + if (rk_iommu_is_paging_enabled(iommu)) + return 0; + + rk_iommu_command(iommu, RK_MMU_CMD_ENABLE_PAGING); + + ret = readx_poll_timeout(rk_iommu_is_paging_enabled, iommu, val, + val, RK_MMU_POLL_PERIOD_US, + RK_MMU_POLL_TIMEOUT_US); + if (ret) + for (i = 0; i < iommu->num_mmu; i++) + dev_err(iommu->dev, "Enable paging request timed out, status: %#08x\n", + rk_iommu_read(iommu->bases[i], RK_MMU_STATUS)); + + return ret; +} + +static int rk_iommu_disable_paging(struct rk_iommu *iommu) +{ + int ret, i; + bool val; + + if (!rk_iommu_is_paging_enabled(iommu)) + return 0; + + rk_iommu_command(iommu, RK_MMU_CMD_DISABLE_PAGING); + + ret = readx_poll_timeout(rk_iommu_is_paging_enabled, iommu, val, + !val, RK_MMU_POLL_PERIOD_US, + RK_MMU_POLL_TIMEOUT_US); + if (ret) + for (i = 0; i < iommu->num_mmu; i++) + dev_err(iommu->dev, "Disable paging request timed out, status: %#08x\n", + rk_iommu_read(iommu->bases[i], RK_MMU_STATUS)); + + return ret; +} + +static int rk_iommu_force_reset(struct rk_iommu *iommu) +{ + int ret, i; + u32 dte_addr; + bool val; + + if (iommu->reset_disabled) + return 0; + + /* + * Check if register DTE_ADDR is working by writing DTE_ADDR_DUMMY + * and verifying that upper 5 nybbles are read back. + */ + for (i = 0; i < iommu->num_mmu; i++) { + rk_iommu_write(iommu->bases[i], RK_MMU_DTE_ADDR, DTE_ADDR_DUMMY); + + dte_addr = rk_iommu_read(iommu->bases[i], 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 = readx_poll_timeout(rk_iommu_is_reset_done, iommu, val, + val, RK_MMU_FORCE_RESET_TIMEOUT_US, + RK_MMU_POLL_TIMEOUT_US); + if (ret) { + dev_err(iommu->dev, "FORCE_RESET command timed out\n"); + return ret; + } + + return 0; +} + +static void log_iova(struct rk_iommu *iommu, int index, dma_addr_t iova) +{ + void __iomem *base = iommu->bases[index]; + 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(base, 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; + irqreturn_t ret = IRQ_NONE; + int i, err; + + err = pm_runtime_get_if_in_use(iommu->dev); + if (WARN_ON_ONCE(err <= 0)) + return ret; + + if (WARN_ON(clk_bulk_enable(iommu->num_clocks, iommu->clocks))) + goto out; + + for (i = 0; i < iommu->num_mmu; i++) { + int_status = rk_iommu_read(iommu->bases[i], RK_MMU_INT_STATUS); + if (int_status == 0) + continue; + + ret = IRQ_HANDLED; + iova = rk_iommu_read(iommu->bases[i], RK_MMU_PAGE_FAULT_ADDR); + + if (int_status & RK_MMU_IRQ_PAGE_FAULT) { + int flags; + + status = rk_iommu_read(iommu->bases[i], 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, i, 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_base_command(iommu->bases[i], RK_MMU_CMD_ZAP_CACHE); + rk_iommu_base_command(iommu->bases[i], 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->bases[i], RK_MMU_INT_CLEAR, int_status); + } + + clk_bulk_disable(iommu->num_clocks, iommu->clocks); + +out: + pm_runtime_put(iommu->dev); + return ret; +} + +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; + int ret; + + iommu = list_entry(pos, struct rk_iommu, node); + + /* Only zap TLBs of IOMMUs that are powered on. */ + ret = pm_runtime_get_if_in_use(iommu->dev); + if (WARN_ON_ONCE(ret < 0)) + continue; + if (ret) { + WARN_ON(clk_bulk_enable(iommu->num_clocks, + iommu->clocks)); + rk_iommu_zap_lines(iommu, iova, size); + clk_bulk_disable(iommu->num_clocks, iommu->clocks); + pm_runtime_put(iommu->dev); + } + } + 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_index, dte; + phys_addr_t pt_phys; + dma_addr_t pt_dma; + + assert_spin_locked(&rk_domain->dt_lock); + + dte_index = rk_iova_dte_index(iova); + dte_addr = &rk_domain->dt[dte_index]; + 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); + + pt_dma = dma_map_single(dma_dev, page_table, SPAGE_SIZE, DMA_TO_DEVICE); + if (dma_mapping_error(dma_dev, pt_dma)) { + dev_err(dma_dev, "DMA mapping error while allocating page table\n"); + free_page((unsigned long)page_table); + return ERR_PTR(-ENOMEM); + } + + dte = rk_mk_dte(pt_dma); + *dte_addr = dte; + + rk_table_flush(rk_domain, pt_dma, NUM_PT_ENTRIES); + rk_table_flush(rk_domain, + rk_domain->dt_dma + dte_index * sizeof(u32), 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 pte_dma, + 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(rk_domain, pte_dma, 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 pte_dma, 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(rk_domain, pte_dma, pte_total); + + /* + * 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, pte_dma, + 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 pte_dma, iova = (dma_addr_t)_iova; + u32 *page_table, *pte_addr; + u32 dte_index, pte_index; + 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); + } + + dte_index = rk_domain->dt[rk_iova_dte_index(iova)]; + pte_index = rk_iova_pte_index(iova); + pte_addr = &page_table[pte_index]; + pte_dma = rk_dte_pt_address(dte_index) + pte_index * sizeof(u32); + ret = rk_iommu_map_iova(rk_domain, pte_addr, pte_dma, 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 pte_dma, 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); + pte_dma = pt_phys + rk_iova_pte_index(iova) * sizeof(u32); + unmap_size = rk_iommu_unmap_iova(rk_domain, pte_addr, pte_dma, 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 rk_iommudata *data = dev->archdata.iommu; + + return data ? data->iommu : NULL; +} + +/* Must be called with iommu powered on and attached */ +static void rk_iommu_disable(struct rk_iommu *iommu) +{ + int i; + + /* Ignore error while disabling, just keep going */ + WARN_ON(clk_bulk_enable(iommu->num_clocks, iommu->clocks)); + rk_iommu_enable_stall(iommu); + rk_iommu_disable_paging(iommu); + for (i = 0; i < iommu->num_mmu; i++) { + rk_iommu_write(iommu->bases[i], RK_MMU_INT_MASK, 0); + rk_iommu_write(iommu->bases[i], RK_MMU_DTE_ADDR, 0); + } + rk_iommu_disable_stall(iommu); + clk_bulk_disable(iommu->num_clocks, iommu->clocks); +} + +/* Must be called with iommu powered on and attached */ +static int rk_iommu_enable(struct rk_iommu *iommu) +{ + struct iommu_domain *domain = iommu->domain; + struct rk_iommu_domain *rk_domain = to_rk_domain(domain); + int ret, i; + + ret = clk_bulk_enable(iommu->num_clocks, iommu->clocks); + if (ret) + return ret; + + ret = rk_iommu_enable_stall(iommu); + if (ret) + goto out_disable_clocks; + + ret = rk_iommu_force_reset(iommu); + if (ret) + goto out_disable_stall; + + for (i = 0; i < iommu->num_mmu; i++) { + rk_iommu_write(iommu->bases[i], RK_MMU_DTE_ADDR, + rk_domain->dt_dma); + rk_iommu_base_command(iommu->bases[i], RK_MMU_CMD_ZAP_CACHE); + rk_iommu_write(iommu->bases[i], RK_MMU_INT_MASK, RK_MMU_IRQ_MASK); + } + + ret = rk_iommu_enable_paging(iommu); + +out_disable_stall: + rk_iommu_disable_stall(iommu); +out_disable_clocks: + clk_bulk_disable(iommu->num_clocks, iommu->clocks); + return ret; +} + +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; + int ret; + + /* Allow 'virtual devices' (eg drm) to detach from domain */ + iommu = rk_iommu_from_dev(dev); + if (!iommu) + return; + + dev_dbg(dev, "Detaching from iommu domain\n"); + + /* iommu already detached */ + if (iommu->domain != domain) + return; + + iommu->domain = NULL; + + spin_lock_irqsave(&rk_domain->iommus_lock, flags); + list_del_init(&iommu->node); + spin_unlock_irqrestore(&rk_domain->iommus_lock, flags); + + ret = pm_runtime_get_if_in_use(iommu->dev); + WARN_ON_ONCE(ret < 0); + if (ret > 0) { + rk_iommu_disable(iommu); + pm_runtime_put(iommu->dev); + } +} + +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; + + /* + * 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; + + dev_dbg(dev, "Attaching to iommu domain\n"); + + /* iommu already attached */ + if (iommu->domain == domain) + return 0; + + if (iommu->domain) + rk_iommu_detach_device(iommu->domain, dev); + + iommu->domain = domain; + + spin_lock_irqsave(&rk_domain->iommus_lock, flags); + list_add_tail(&iommu->node, &rk_domain->iommus); + spin_unlock_irqrestore(&rk_domain->iommus_lock, flags); + + ret = pm_runtime_get_if_in_use(iommu->dev); + if (!ret || WARN_ON_ONCE(ret < 0)) + return 0; + + ret = rk_iommu_enable(iommu); + if (ret) + rk_iommu_detach_device(iommu->domain, dev); + + pm_runtime_put(iommu->dev); + + return ret; +} + +static struct iommu_domain *rk_iommu_domain_alloc(unsigned type) +{ + struct rk_iommu_domain *rk_domain; + + if (type != IOMMU_DOMAIN_UNMANAGED && type != IOMMU_DOMAIN_DMA) + return NULL; + + if (!dma_dev) + return NULL; + + rk_domain = kzalloc(sizeof(*rk_domain), GFP_KERNEL); + if (!rk_domain) + return NULL; + + if (type == IOMMU_DOMAIN_DMA && + iommu_get_dma_cookie(&rk_domain->domain)) + goto err_free_domain; + + /* + * 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_put_cookie; + + rk_domain->dt_dma = dma_map_single(dma_dev, rk_domain->dt, + SPAGE_SIZE, DMA_TO_DEVICE); + if (dma_mapping_error(dma_dev, rk_domain->dt_dma)) { + dev_err(dma_dev, "DMA map error for DT\n"); + goto err_free_dt; + } + + rk_table_flush(rk_domain, rk_domain->dt_dma, NUM_DT_ENTRIES); + + spin_lock_init(&rk_domain->iommus_lock); + spin_lock_init(&rk_domain->dt_lock); + INIT_LIST_HEAD(&rk_domain->iommus); + + rk_domain->domain.geometry.aperture_start = 0; + rk_domain->domain.geometry.aperture_end = DMA_BIT_MASK(32); + rk_domain->domain.geometry.force_aperture = true; + + return &rk_domain->domain; + +err_free_dt: + free_page((unsigned long)rk_domain->dt); +err_put_cookie: + if (type == IOMMU_DOMAIN_DMA) + iommu_put_dma_cookie(&rk_domain->domain); +err_free_domain: + 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); + dma_unmap_single(dma_dev, pt_phys, + SPAGE_SIZE, DMA_TO_DEVICE); + free_page((unsigned long)page_table); + } + } + + dma_unmap_single(dma_dev, rk_domain->dt_dma, + SPAGE_SIZE, DMA_TO_DEVICE); + free_page((unsigned long)rk_domain->dt); + + if (domain->type == IOMMU_DOMAIN_DMA) + iommu_put_dma_cookie(&rk_domain->domain); + kfree(rk_domain); +} + +static int rk_iommu_add_device(struct device *dev) +{ + struct iommu_group *group; + struct rk_iommu *iommu; + struct rk_iommudata *data; + + data = dev->archdata.iommu; + if (!data) + return -ENODEV; + + iommu = rk_iommu_from_dev(dev); + + group = iommu_group_get_for_dev(dev); + if (IS_ERR(group)) + return PTR_ERR(group); + iommu_group_put(group); + + iommu_device_link(&iommu->iommu, dev); + data->link = device_link_add(dev, iommu->dev, DL_FLAG_PM_RUNTIME); + + return 0; +} + +static void rk_iommu_remove_device(struct device *dev) +{ + struct rk_iommu *iommu; + struct rk_iommudata *data = dev->archdata.iommu; + + iommu = rk_iommu_from_dev(dev); + + device_link_del(data->link); + iommu_device_unlink(&iommu->iommu, dev); + iommu_group_remove_device(dev); +} + +static struct iommu_group *rk_iommu_device_group(struct device *dev) +{ + struct rk_iommu *iommu; + + iommu = rk_iommu_from_dev(dev); + + return iommu_group_ref_get(iommu->group); +} + +static int rk_iommu_of_xlate(struct device *dev, + struct of_phandle_args *args) +{ + struct platform_device *iommu_dev; + struct rk_iommudata *data; + + data = devm_kzalloc(dma_dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + iommu_dev = of_find_device_by_node(args->np); + + data->iommu = platform_get_drvdata(iommu_dev); + dev->archdata.iommu = data; + + platform_device_put(iommu_dev); + + return 0; +} + +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, + .device_group = rk_iommu_device_group, + .pgsize_bitmap = RK_IOMMU_PGSIZE_BITMAP, + .of_xlate = rk_iommu_of_xlate, +}; + +static int rk_iommu_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct rk_iommu *iommu; + struct resource *res; + int num_res = pdev->num_resources; + int err, i, irq; + + iommu = devm_kzalloc(dev, sizeof(*iommu), GFP_KERNEL); + if (!iommu) + return -ENOMEM; + + platform_set_drvdata(pdev, iommu); + iommu->dev = dev; + iommu->num_mmu = 0; + + iommu->bases = devm_kcalloc(dev, num_res, sizeof(*iommu->bases), + GFP_KERNEL); + if (!iommu->bases) + return -ENOMEM; + + for (i = 0; i < num_res; i++) { + res = platform_get_resource(pdev, IORESOURCE_MEM, i); + if (!res) + continue; + iommu->bases[i] = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(iommu->bases[i])) + continue; + iommu->num_mmu++; + } + if (iommu->num_mmu == 0) + return PTR_ERR(iommu->bases[0]); + + iommu->reset_disabled = device_property_read_bool(dev, + "rockchip,disable-mmu-reset"); + + iommu->num_clocks = ARRAY_SIZE(rk_iommu_clocks); + iommu->clocks = devm_kcalloc(iommu->dev, iommu->num_clocks, + sizeof(*iommu->clocks), GFP_KERNEL); + if (!iommu->clocks) + return -ENOMEM; + + for (i = 0; i < iommu->num_clocks; ++i) + iommu->clocks[i].id = rk_iommu_clocks[i]; + + /* + * iommu clocks should be present for all new devices and devicetrees + * but there are older devicetrees without clocks out in the wild. + * So clocks as optional for the time being. + */ + err = devm_clk_bulk_get(iommu->dev, iommu->num_clocks, iommu->clocks); + if (err == -ENOENT) + iommu->num_clocks = 0; + else if (err) + return err; + + err = clk_bulk_prepare(iommu->num_clocks, iommu->clocks); + if (err) + return err; + + iommu->group = iommu_group_alloc(); + if (IS_ERR(iommu->group)) { + err = PTR_ERR(iommu->group); + goto err_unprepare_clocks; + } + + err = iommu_device_sysfs_add(&iommu->iommu, dev, NULL, dev_name(dev)); + if (err) + goto err_put_group; + + iommu_device_set_ops(&iommu->iommu, &rk_iommu_ops); + iommu_device_set_fwnode(&iommu->iommu, &dev->of_node->fwnode); + + err = iommu_device_register(&iommu->iommu); + if (err) + goto err_remove_sysfs; + + /* + * Use the first registered IOMMU device for domain to use with DMA + * API, since a domain might not physically correspond to a single + * IOMMU device.. + */ + if (!dma_dev) + dma_dev = &pdev->dev; + + bus_set_iommu(&platform_bus_type, &rk_iommu_ops); + + pm_runtime_enable(dev); + + i = 0; + while ((irq = platform_get_irq(pdev, i++)) != -ENXIO) { + if (irq < 0) + return irq; + + err = devm_request_irq(iommu->dev, irq, rk_iommu_irq, + IRQF_SHARED, dev_name(dev), iommu); + if (err) { + pm_runtime_disable(dev); + goto err_remove_sysfs; + } + } + + return 0; +err_remove_sysfs: + iommu_device_sysfs_remove(&iommu->iommu); +err_put_group: + iommu_group_put(iommu->group); +err_unprepare_clocks: + clk_bulk_unprepare(iommu->num_clocks, iommu->clocks); + return err; +} + +static void rk_iommu_shutdown(struct platform_device *pdev) +{ + struct rk_iommu *iommu = platform_get_drvdata(pdev); + int i = 0, irq; + + while ((irq = platform_get_irq(pdev, i++)) != -ENXIO) + devm_free_irq(iommu->dev, irq, iommu); + + pm_runtime_force_suspend(&pdev->dev); +} + +static int __maybe_unused rk_iommu_suspend(struct device *dev) +{ + struct rk_iommu *iommu = dev_get_drvdata(dev); + + if (!iommu->domain) + return 0; + + rk_iommu_disable(iommu); + return 0; +} + +static int __maybe_unused rk_iommu_resume(struct device *dev) +{ + struct rk_iommu *iommu = dev_get_drvdata(dev); + + if (!iommu->domain) + return 0; + + return rk_iommu_enable(iommu); +} + +static const struct dev_pm_ops rk_iommu_pm_ops = { + SET_RUNTIME_PM_OPS(rk_iommu_suspend, rk_iommu_resume, NULL) + SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, + pm_runtime_force_resume) +}; + +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, + .shutdown = rk_iommu_shutdown, + .driver = { + .name = "rk_iommu", + .of_match_table = rk_iommu_dt_ids, + .pm = &rk_iommu_pm_ops, + .suppress_bind_attrs = true, + }, +}; + +static int __init rk_iommu_init(void) +{ + return platform_driver_register(&rk_iommu_driver); +} +subsys_initcall(rk_iommu_init); + +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"); |