--- /dev/null
+/*
+ * 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 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);
+}
+
+/**
+ * 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 = domain->priv;
+ 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 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);
+
+ /*
+ * Zap the first iova of newly allocated page table so iommu evicts
+ * old cached value of new dte from the iotlb.
+ */
+ rk_iommu_zap_iova(rk_domain, iova, SPAGE_SIZE);
+
+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);
+
+ 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 = domain->priv;
+ 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 = domain->priv;
+ 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 = domain->priv;
+ 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_info(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 = domain->priv;
+ 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_info(dev, "Detached from iommu domain\n");
+}
+
+static int rk_iommu_domain_init(struct iommu_domain *domain)
+{
+ struct rk_iommu_domain *rk_domain;
+
+ rk_domain = kzalloc(sizeof(*rk_domain), GFP_KERNEL);
+ if (!rk_domain)
+ return -ENOMEM;
+
+ /*
+ * 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);
+
+ domain->priv = rk_domain;
+
+ return 0;
+err_dt:
+ kfree(rk_domain);
+ return -ENOMEM;
+}
+
+static void rk_iommu_domain_destroy(struct iommu_domain *domain)
+{
+ struct rk_iommu_domain *rk_domain = domain->priv;
+ 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(domain->priv);
+ domain->priv = NULL;
+}
+
+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_init = rk_iommu_domain_init,
+ .domain_destroy = rk_iommu_domain_destroy,
+ .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;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id rk_iommu_dt_ids[] = {
+ { .compatible = "rockchip,iommu" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, rk_iommu_dt_ids);
+#endif
+
+static struct platform_driver rk_iommu_driver = {
+ .probe = rk_iommu_probe,
+ .remove = rk_iommu_remove,
+ .driver = {
+ .name = "rk_iommu",
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(rk_iommu_dt_ids),
+ },
+};
+
+static int __init rk_iommu_init(void)
+{
+ int ret;
+
+ 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");
projects / GitHub / MotorolaMobilityLLC / kernel-slsi.git / commitdiff