diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/iommu/sun50i-iommu.c | 1080 |
1 files changed, 1080 insertions, 0 deletions
diff --git a/drivers/iommu/sun50i-iommu.c b/drivers/iommu/sun50i-iommu.c new file mode 100644 index 000000000..5b585eace --- /dev/null +++ b/drivers/iommu/sun50i-iommu.c @@ -0,0 +1,1080 @@ +// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +// Copyright (C) 2016-2018, Allwinner Technology CO., LTD. +// Copyright (C) 2019-2020, Cerno + +#include <linux/bitfield.h> +#include <linux/bug.h> +#include <linux/clk.h> +#include <linux/device.h> +#include <linux/dma-direction.h> +#include <linux/dma-mapping.h> +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/interrupt.h> +#include <linux/iommu.h> +#include <linux/iopoll.h> +#include <linux/ioport.h> +#include <linux/log2.h> +#include <linux/module.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/pm.h> +#include <linux/pm_runtime.h> +#include <linux/reset.h> +#include <linux/sizes.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/types.h> + +#define IOMMU_RESET_REG 0x010 +#define IOMMU_RESET_RELEASE_ALL 0xffffffff +#define IOMMU_ENABLE_REG 0x020 +#define IOMMU_ENABLE_ENABLE BIT(0) + +#define IOMMU_BYPASS_REG 0x030 +#define IOMMU_AUTO_GATING_REG 0x040 +#define IOMMU_AUTO_GATING_ENABLE BIT(0) + +#define IOMMU_WBUF_CTRL_REG 0x044 +#define IOMMU_OOO_CTRL_REG 0x048 +#define IOMMU_4KB_BDY_PRT_CTRL_REG 0x04c +#define IOMMU_TTB_REG 0x050 +#define IOMMU_TLB_ENABLE_REG 0x060 +#define IOMMU_TLB_PREFETCH_REG 0x070 +#define IOMMU_TLB_PREFETCH_MASTER_ENABLE(m) BIT(m) + +#define IOMMU_TLB_FLUSH_REG 0x080 +#define IOMMU_TLB_FLUSH_PTW_CACHE BIT(17) +#define IOMMU_TLB_FLUSH_MACRO_TLB BIT(16) +#define IOMMU_TLB_FLUSH_MICRO_TLB(i) (BIT(i) & GENMASK(5, 0)) + +#define IOMMU_TLB_IVLD_ADDR_REG 0x090 +#define IOMMU_TLB_IVLD_ADDR_MASK_REG 0x094 +#define IOMMU_TLB_IVLD_ENABLE_REG 0x098 +#define IOMMU_TLB_IVLD_ENABLE_ENABLE BIT(0) + +#define IOMMU_PC_IVLD_ADDR_REG 0x0a0 +#define IOMMU_PC_IVLD_ENABLE_REG 0x0a8 +#define IOMMU_PC_IVLD_ENABLE_ENABLE BIT(0) + +#define IOMMU_DM_AUT_CTRL_REG(d) (0x0b0 + ((d) / 2) * 4) +#define IOMMU_DM_AUT_CTRL_RD_UNAVAIL(d, m) (1 << (((d & 1) * 16) + ((m) * 2))) +#define IOMMU_DM_AUT_CTRL_WR_UNAVAIL(d, m) (1 << (((d & 1) * 16) + ((m) * 2) + 1)) + +#define IOMMU_DM_AUT_OVWT_REG 0x0d0 +#define IOMMU_INT_ENABLE_REG 0x100 +#define IOMMU_INT_CLR_REG 0x104 +#define IOMMU_INT_STA_REG 0x108 +#define IOMMU_INT_ERR_ADDR_REG(i) (0x110 + (i) * 4) +#define IOMMU_INT_ERR_ADDR_L1_REG 0x130 +#define IOMMU_INT_ERR_ADDR_L2_REG 0x134 +#define IOMMU_INT_ERR_DATA_REG(i) (0x150 + (i) * 4) +#define IOMMU_L1PG_INT_REG 0x0180 +#define IOMMU_L2PG_INT_REG 0x0184 + +#define IOMMU_INT_INVALID_L2PG BIT(17) +#define IOMMU_INT_INVALID_L1PG BIT(16) +#define IOMMU_INT_MASTER_PERMISSION(m) BIT(m) +#define IOMMU_INT_MASTER_MASK (IOMMU_INT_MASTER_PERMISSION(0) | \ + IOMMU_INT_MASTER_PERMISSION(1) | \ + IOMMU_INT_MASTER_PERMISSION(2) | \ + IOMMU_INT_MASTER_PERMISSION(3) | \ + IOMMU_INT_MASTER_PERMISSION(4) | \ + IOMMU_INT_MASTER_PERMISSION(5)) +#define IOMMU_INT_MASK (IOMMU_INT_INVALID_L1PG | \ + IOMMU_INT_INVALID_L2PG | \ + IOMMU_INT_MASTER_MASK) + +#define PT_ENTRY_SIZE sizeof(u32) + +#define NUM_DT_ENTRIES 4096 +#define DT_SIZE (NUM_DT_ENTRIES * PT_ENTRY_SIZE) + +#define NUM_PT_ENTRIES 256 +#define PT_SIZE (NUM_PT_ENTRIES * PT_ENTRY_SIZE) + +#define SPAGE_SIZE 4096 + +struct sun50i_iommu { + struct iommu_device iommu; + + /* Lock to modify the IOMMU registers */ + spinlock_t iommu_lock; + + struct device *dev; + void __iomem *base; + struct reset_control *reset; + struct clk *clk; + + struct iommu_domain *domain; + struct iommu_group *group; + struct kmem_cache *pt_pool; +}; + +struct sun50i_iommu_domain { + struct iommu_domain domain; + + /* Number of devices attached to the domain */ + refcount_t refcnt; + + /* L1 Page Table */ + u32 *dt; + dma_addr_t dt_dma; + + struct sun50i_iommu *iommu; +}; + +static struct sun50i_iommu_domain *to_sun50i_domain(struct iommu_domain *domain) +{ + return container_of(domain, struct sun50i_iommu_domain, domain); +} + +static struct sun50i_iommu *sun50i_iommu_from_dev(struct device *dev) +{ + return dev_iommu_priv_get(dev); +} + +static u32 iommu_read(struct sun50i_iommu *iommu, u32 offset) +{ + return readl(iommu->base + offset); +} + +static void iommu_write(struct sun50i_iommu *iommu, u32 offset, u32 value) +{ + writel(value, iommu->base + offset); +} + +/* + * The Allwinner H6 IOMMU uses a 2-level page table. + * + * The first level is the usual Directory Table (DT), that consists of + * 4096 4-bytes Directory Table Entries (DTE), each pointing to a Page + * Table (PT). + * + * Each PT consits of 256 4-bytes Page Table Entries (PTE), each + * pointing to a 4kB page of physical memory. + * + * The IOMMU supports a single DT, pointed by the IOMMU_TTB_REG + * register that contains its physical address. + */ + +#define SUN50I_IOVA_DTE_MASK GENMASK(31, 20) +#define SUN50I_IOVA_PTE_MASK GENMASK(19, 12) +#define SUN50I_IOVA_PAGE_MASK GENMASK(11, 0) + +static u32 sun50i_iova_get_dte_index(dma_addr_t iova) +{ + return FIELD_GET(SUN50I_IOVA_DTE_MASK, iova); +} + +static u32 sun50i_iova_get_pte_index(dma_addr_t iova) +{ + return FIELD_GET(SUN50I_IOVA_PTE_MASK, iova); +} + +static u32 sun50i_iova_get_page_offset(dma_addr_t iova) +{ + return FIELD_GET(SUN50I_IOVA_PAGE_MASK, iova); +} + +/* + * Each Directory Table Entry has a Page Table address and a valid + * bit: + + * +---------------------+-----------+-+ + * | PT address | Reserved |V| + * +---------------------+-----------+-+ + * 31:10 - Page Table address + * 9:2 - Reserved + * 1:0 - 1 if the entry is valid + */ + +#define SUN50I_DTE_PT_ADDRESS_MASK GENMASK(31, 10) +#define SUN50I_DTE_PT_ATTRS GENMASK(1, 0) +#define SUN50I_DTE_PT_VALID 1 + +static phys_addr_t sun50i_dte_get_pt_address(u32 dte) +{ + return (phys_addr_t)dte & SUN50I_DTE_PT_ADDRESS_MASK; +} + +static bool sun50i_dte_is_pt_valid(u32 dte) +{ + return (dte & SUN50I_DTE_PT_ATTRS) == SUN50I_DTE_PT_VALID; +} + +static u32 sun50i_mk_dte(dma_addr_t pt_dma) +{ + return (pt_dma & SUN50I_DTE_PT_ADDRESS_MASK) | SUN50I_DTE_PT_VALID; +} + +/* + * Each PTE has a Page address, an authority index and a valid bit: + * + * +----------------+-----+-----+-----+---+-----+ + * | Page address | Rsv | ACI | Rsv | V | Rsv | + * +----------------+-----+-----+-----+---+-----+ + * 31:12 - Page address + * 11:8 - Reserved + * 7:4 - Authority Control Index + * 3:2 - Reserved + * 1 - 1 if the entry is valid + * 0 - Reserved + * + * The way permissions work is that the IOMMU has 16 "domains" that + * can be configured to give each masters either read or write + * permissions through the IOMMU_DM_AUT_CTRL_REG registers. The domain + * 0 seems like the default domain, and its permissions in the + * IOMMU_DM_AUT_CTRL_REG are only read-only, so it's not really + * useful to enforce any particular permission. + * + * Each page entry will then have a reference to the domain they are + * affected to, so that we can actually enforce them on a per-page + * basis. + * + * In order to make it work with the IOMMU framework, we will be using + * 4 different domains, starting at 1: RD_WR, RD, WR and NONE + * depending on the permission we want to enforce. Each domain will + * have each master setup in the same way, since the IOMMU framework + * doesn't seem to restrict page access on a per-device basis. And + * then we will use the relevant domain index when generating the page + * table entry depending on the permissions we want to be enforced. + */ + +enum sun50i_iommu_aci { + SUN50I_IOMMU_ACI_DO_NOT_USE = 0, + SUN50I_IOMMU_ACI_NONE, + SUN50I_IOMMU_ACI_RD, + SUN50I_IOMMU_ACI_WR, + SUN50I_IOMMU_ACI_RD_WR, +}; + +#define SUN50I_PTE_PAGE_ADDRESS_MASK GENMASK(31, 12) +#define SUN50I_PTE_ACI_MASK GENMASK(7, 4) +#define SUN50I_PTE_PAGE_VALID BIT(1) + +static phys_addr_t sun50i_pte_get_page_address(u32 pte) +{ + return (phys_addr_t)pte & SUN50I_PTE_PAGE_ADDRESS_MASK; +} + +static enum sun50i_iommu_aci sun50i_get_pte_aci(u32 pte) +{ + return FIELD_GET(SUN50I_PTE_ACI_MASK, pte); +} + +static bool sun50i_pte_is_page_valid(u32 pte) +{ + return pte & SUN50I_PTE_PAGE_VALID; +} + +static u32 sun50i_mk_pte(phys_addr_t page, int prot) +{ + enum sun50i_iommu_aci aci; + u32 flags = 0; + + if ((prot & (IOMMU_READ | IOMMU_WRITE)) == (IOMMU_READ | IOMMU_WRITE)) + aci = SUN50I_IOMMU_ACI_RD_WR; + else if (prot & IOMMU_READ) + aci = SUN50I_IOMMU_ACI_RD; + else if (prot & IOMMU_WRITE) + aci = SUN50I_IOMMU_ACI_WR; + else + aci = SUN50I_IOMMU_ACI_NONE; + + flags |= FIELD_PREP(SUN50I_PTE_ACI_MASK, aci); + page &= SUN50I_PTE_PAGE_ADDRESS_MASK; + return page | flags | SUN50I_PTE_PAGE_VALID; +} + +static void sun50i_table_flush(struct sun50i_iommu_domain *sun50i_domain, + void *vaddr, unsigned int count) +{ + struct sun50i_iommu *iommu = sun50i_domain->iommu; + dma_addr_t dma = virt_to_phys(vaddr); + size_t size = count * PT_ENTRY_SIZE; + + dma_sync_single_for_device(iommu->dev, dma, size, DMA_TO_DEVICE); +} + +static void sun50i_iommu_zap_iova(struct sun50i_iommu *iommu, + unsigned long iova) +{ + u32 reg; + int ret; + + iommu_write(iommu, IOMMU_TLB_IVLD_ADDR_REG, iova); + iommu_write(iommu, IOMMU_TLB_IVLD_ADDR_MASK_REG, GENMASK(31, 12)); + iommu_write(iommu, IOMMU_TLB_IVLD_ENABLE_REG, + IOMMU_TLB_IVLD_ENABLE_ENABLE); + + ret = readl_poll_timeout_atomic(iommu->base + IOMMU_TLB_IVLD_ENABLE_REG, + reg, !reg, 1, 2000); + if (ret) + dev_warn(iommu->dev, "TLB invalidation timed out!\n"); +} + +static void sun50i_iommu_zap_ptw_cache(struct sun50i_iommu *iommu, + unsigned long iova) +{ + u32 reg; + int ret; + + iommu_write(iommu, IOMMU_PC_IVLD_ADDR_REG, iova); + iommu_write(iommu, IOMMU_PC_IVLD_ENABLE_REG, + IOMMU_PC_IVLD_ENABLE_ENABLE); + + ret = readl_poll_timeout_atomic(iommu->base + IOMMU_PC_IVLD_ENABLE_REG, + reg, !reg, 1, 2000); + if (ret) + dev_warn(iommu->dev, "PTW cache invalidation timed out!\n"); +} + +static void sun50i_iommu_zap_range(struct sun50i_iommu *iommu, + unsigned long iova, size_t size) +{ + assert_spin_locked(&iommu->iommu_lock); + + iommu_write(iommu, IOMMU_AUTO_GATING_REG, 0); + + sun50i_iommu_zap_iova(iommu, iova); + sun50i_iommu_zap_iova(iommu, iova + SPAGE_SIZE); + if (size > SPAGE_SIZE) { + sun50i_iommu_zap_iova(iommu, iova + size); + sun50i_iommu_zap_iova(iommu, iova + size + SPAGE_SIZE); + } + sun50i_iommu_zap_ptw_cache(iommu, iova); + sun50i_iommu_zap_ptw_cache(iommu, iova + SZ_1M); + if (size > SZ_1M) { + sun50i_iommu_zap_ptw_cache(iommu, iova + size); + sun50i_iommu_zap_ptw_cache(iommu, iova + size + SZ_1M); + } + + iommu_write(iommu, IOMMU_AUTO_GATING_REG, IOMMU_AUTO_GATING_ENABLE); +} + +static int sun50i_iommu_flush_all_tlb(struct sun50i_iommu *iommu) +{ + u32 reg; + int ret; + + assert_spin_locked(&iommu->iommu_lock); + + iommu_write(iommu, + IOMMU_TLB_FLUSH_REG, + IOMMU_TLB_FLUSH_PTW_CACHE | + IOMMU_TLB_FLUSH_MACRO_TLB | + IOMMU_TLB_FLUSH_MICRO_TLB(5) | + IOMMU_TLB_FLUSH_MICRO_TLB(4) | + IOMMU_TLB_FLUSH_MICRO_TLB(3) | + IOMMU_TLB_FLUSH_MICRO_TLB(2) | + IOMMU_TLB_FLUSH_MICRO_TLB(1) | + IOMMU_TLB_FLUSH_MICRO_TLB(0)); + + ret = readl_poll_timeout_atomic(iommu->base + IOMMU_TLB_FLUSH_REG, + reg, !reg, + 1, 2000); + if (ret) + dev_warn(iommu->dev, "TLB Flush timed out!\n"); + + return ret; +} + +static void sun50i_iommu_flush_iotlb_all(struct iommu_domain *domain) +{ + struct sun50i_iommu_domain *sun50i_domain = to_sun50i_domain(domain); + struct sun50i_iommu *iommu = sun50i_domain->iommu; + unsigned long flags; + + /* + * At boot, we'll have a first call into .flush_iotlb_all right after + * .probe_device, and since we link our (single) domain to our iommu in + * the .attach_device callback, we don't have that pointer set. + * + * It shouldn't really be any trouble to ignore it though since we flush + * all caches as part of the device powerup. + */ + if (!iommu) + return; + + spin_lock_irqsave(&iommu->iommu_lock, flags); + sun50i_iommu_flush_all_tlb(iommu); + spin_unlock_irqrestore(&iommu->iommu_lock, flags); +} + +static void sun50i_iommu_iotlb_sync_map(struct iommu_domain *domain, + unsigned long iova, size_t size) +{ + struct sun50i_iommu_domain *sun50i_domain = to_sun50i_domain(domain); + struct sun50i_iommu *iommu = sun50i_domain->iommu; + unsigned long flags; + + spin_lock_irqsave(&iommu->iommu_lock, flags); + sun50i_iommu_zap_range(iommu, iova, size); + spin_unlock_irqrestore(&iommu->iommu_lock, flags); +} + +static void sun50i_iommu_iotlb_sync(struct iommu_domain *domain, + struct iommu_iotlb_gather *gather) +{ + sun50i_iommu_flush_iotlb_all(domain); +} + +static int sun50i_iommu_enable(struct sun50i_iommu *iommu) +{ + struct sun50i_iommu_domain *sun50i_domain; + unsigned long flags; + int ret; + + if (!iommu->domain) + return 0; + + sun50i_domain = to_sun50i_domain(iommu->domain); + + ret = reset_control_deassert(iommu->reset); + if (ret) + return ret; + + ret = clk_prepare_enable(iommu->clk); + if (ret) + goto err_reset_assert; + + spin_lock_irqsave(&iommu->iommu_lock, flags); + + iommu_write(iommu, IOMMU_TTB_REG, sun50i_domain->dt_dma); + iommu_write(iommu, IOMMU_TLB_PREFETCH_REG, + IOMMU_TLB_PREFETCH_MASTER_ENABLE(0) | + IOMMU_TLB_PREFETCH_MASTER_ENABLE(1) | + IOMMU_TLB_PREFETCH_MASTER_ENABLE(2) | + IOMMU_TLB_PREFETCH_MASTER_ENABLE(3) | + IOMMU_TLB_PREFETCH_MASTER_ENABLE(4) | + IOMMU_TLB_PREFETCH_MASTER_ENABLE(5)); + iommu_write(iommu, IOMMU_INT_ENABLE_REG, IOMMU_INT_MASK); + iommu_write(iommu, IOMMU_DM_AUT_CTRL_REG(SUN50I_IOMMU_ACI_NONE), + IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 0) | + IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 0) | + IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 1) | + IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 1) | + IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 2) | + IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 2) | + IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 3) | + IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 3) | + IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 4) | + IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 4) | + IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 5) | + IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 5)); + + iommu_write(iommu, IOMMU_DM_AUT_CTRL_REG(SUN50I_IOMMU_ACI_RD), + IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_RD, 0) | + IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_RD, 1) | + IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_RD, 2) | + IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_RD, 3) | + IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_RD, 4) | + IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_RD, 5)); + + iommu_write(iommu, IOMMU_DM_AUT_CTRL_REG(SUN50I_IOMMU_ACI_WR), + IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_WR, 0) | + IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_WR, 1) | + IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_WR, 2) | + IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_WR, 3) | + IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_WR, 4) | + IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_WR, 5)); + + ret = sun50i_iommu_flush_all_tlb(iommu); + if (ret) { + spin_unlock_irqrestore(&iommu->iommu_lock, flags); + goto err_clk_disable; + } + + iommu_write(iommu, IOMMU_AUTO_GATING_REG, IOMMU_AUTO_GATING_ENABLE); + iommu_write(iommu, IOMMU_ENABLE_REG, IOMMU_ENABLE_ENABLE); + + spin_unlock_irqrestore(&iommu->iommu_lock, flags); + + return 0; + +err_clk_disable: + clk_disable_unprepare(iommu->clk); + +err_reset_assert: + reset_control_assert(iommu->reset); + + return ret; +} + +static void sun50i_iommu_disable(struct sun50i_iommu *iommu) +{ + unsigned long flags; + + spin_lock_irqsave(&iommu->iommu_lock, flags); + + iommu_write(iommu, IOMMU_ENABLE_REG, 0); + iommu_write(iommu, IOMMU_TTB_REG, 0); + + spin_unlock_irqrestore(&iommu->iommu_lock, flags); + + clk_disable_unprepare(iommu->clk); + reset_control_assert(iommu->reset); +} + +static void *sun50i_iommu_alloc_page_table(struct sun50i_iommu *iommu, + gfp_t gfp) +{ + dma_addr_t pt_dma; + u32 *page_table; + + page_table = kmem_cache_zalloc(iommu->pt_pool, gfp); + if (!page_table) + return ERR_PTR(-ENOMEM); + + pt_dma = dma_map_single(iommu->dev, page_table, PT_SIZE, DMA_TO_DEVICE); + if (dma_mapping_error(iommu->dev, pt_dma)) { + dev_err(iommu->dev, "Couldn't map L2 Page Table\n"); + kmem_cache_free(iommu->pt_pool, page_table); + return ERR_PTR(-ENOMEM); + } + + /* We rely on the physical address and DMA address being the same */ + WARN_ON(pt_dma != virt_to_phys(page_table)); + + return page_table; +} + +static void sun50i_iommu_free_page_table(struct sun50i_iommu *iommu, + u32 *page_table) +{ + phys_addr_t pt_phys = virt_to_phys(page_table); + + dma_unmap_single(iommu->dev, pt_phys, PT_SIZE, DMA_TO_DEVICE); + kmem_cache_free(iommu->pt_pool, page_table); +} + +static u32 *sun50i_dte_get_page_table(struct sun50i_iommu_domain *sun50i_domain, + dma_addr_t iova, gfp_t gfp) +{ + struct sun50i_iommu *iommu = sun50i_domain->iommu; + u32 *page_table; + u32 *dte_addr; + u32 old_dte; + u32 dte; + + dte_addr = &sun50i_domain->dt[sun50i_iova_get_dte_index(iova)]; + dte = *dte_addr; + if (sun50i_dte_is_pt_valid(dte)) { + phys_addr_t pt_phys = sun50i_dte_get_pt_address(dte); + return (u32 *)phys_to_virt(pt_phys); + } + + page_table = sun50i_iommu_alloc_page_table(iommu, gfp); + if (IS_ERR(page_table)) + return page_table; + + dte = sun50i_mk_dte(virt_to_phys(page_table)); + old_dte = cmpxchg(dte_addr, 0, dte); + if (old_dte) { + phys_addr_t installed_pt_phys = + sun50i_dte_get_pt_address(old_dte); + u32 *installed_pt = phys_to_virt(installed_pt_phys); + u32 *drop_pt = page_table; + + page_table = installed_pt; + dte = old_dte; + sun50i_iommu_free_page_table(iommu, drop_pt); + } + + sun50i_table_flush(sun50i_domain, page_table, NUM_PT_ENTRIES); + sun50i_table_flush(sun50i_domain, dte_addr, 1); + + return page_table; +} + +static int sun50i_iommu_map(struct iommu_domain *domain, unsigned long iova, + phys_addr_t paddr, size_t size, int prot, gfp_t gfp) +{ + struct sun50i_iommu_domain *sun50i_domain = to_sun50i_domain(domain); + struct sun50i_iommu *iommu = sun50i_domain->iommu; + u32 pte_index; + u32 *page_table, *pte_addr; + int ret = 0; + + page_table = sun50i_dte_get_page_table(sun50i_domain, iova, gfp); + if (IS_ERR(page_table)) { + ret = PTR_ERR(page_table); + goto out; + } + + pte_index = sun50i_iova_get_pte_index(iova); + pte_addr = &page_table[pte_index]; + if (unlikely(sun50i_pte_is_page_valid(*pte_addr))) { + phys_addr_t page_phys = sun50i_pte_get_page_address(*pte_addr); + dev_err(iommu->dev, + "iova %pad already mapped to %pa cannot remap to %pa prot: %#x\n", + &iova, &page_phys, &paddr, prot); + ret = -EBUSY; + goto out; + } + + *pte_addr = sun50i_mk_pte(paddr, prot); + sun50i_table_flush(sun50i_domain, pte_addr, 1); + +out: + return ret; +} + +static size_t sun50i_iommu_unmap(struct iommu_domain *domain, unsigned long iova, + size_t size, struct iommu_iotlb_gather *gather) +{ + struct sun50i_iommu_domain *sun50i_domain = to_sun50i_domain(domain); + phys_addr_t pt_phys; + u32 *pte_addr; + u32 dte; + + dte = sun50i_domain->dt[sun50i_iova_get_dte_index(iova)]; + if (!sun50i_dte_is_pt_valid(dte)) + return 0; + + pt_phys = sun50i_dte_get_pt_address(dte); + pte_addr = (u32 *)phys_to_virt(pt_phys) + sun50i_iova_get_pte_index(iova); + + if (!sun50i_pte_is_page_valid(*pte_addr)) + return 0; + + memset(pte_addr, 0, sizeof(*pte_addr)); + sun50i_table_flush(sun50i_domain, pte_addr, 1); + + return SZ_4K; +} + +static phys_addr_t sun50i_iommu_iova_to_phys(struct iommu_domain *domain, + dma_addr_t iova) +{ + struct sun50i_iommu_domain *sun50i_domain = to_sun50i_domain(domain); + phys_addr_t pt_phys; + u32 *page_table; + u32 dte, pte; + + dte = sun50i_domain->dt[sun50i_iova_get_dte_index(iova)]; + if (!sun50i_dte_is_pt_valid(dte)) + return 0; + + pt_phys = sun50i_dte_get_pt_address(dte); + page_table = (u32 *)phys_to_virt(pt_phys); + pte = page_table[sun50i_iova_get_pte_index(iova)]; + if (!sun50i_pte_is_page_valid(pte)) + return 0; + + return sun50i_pte_get_page_address(pte) + + sun50i_iova_get_page_offset(iova); +} + +static struct iommu_domain *sun50i_iommu_domain_alloc(unsigned type) +{ + struct sun50i_iommu_domain *sun50i_domain; + + if (type != IOMMU_DOMAIN_DMA && + type != IOMMU_DOMAIN_UNMANAGED) + return NULL; + + sun50i_domain = kzalloc(sizeof(*sun50i_domain), GFP_KERNEL); + if (!sun50i_domain) + return NULL; + + sun50i_domain->dt = (u32 *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, + get_order(DT_SIZE)); + if (!sun50i_domain->dt) + goto err_free_domain; + + refcount_set(&sun50i_domain->refcnt, 1); + + sun50i_domain->domain.geometry.aperture_start = 0; + sun50i_domain->domain.geometry.aperture_end = DMA_BIT_MASK(32); + sun50i_domain->domain.geometry.force_aperture = true; + + return &sun50i_domain->domain; + +err_free_domain: + kfree(sun50i_domain); + + return NULL; +} + +static void sun50i_iommu_domain_free(struct iommu_domain *domain) +{ + struct sun50i_iommu_domain *sun50i_domain = to_sun50i_domain(domain); + + free_pages((unsigned long)sun50i_domain->dt, get_order(DT_SIZE)); + sun50i_domain->dt = NULL; + + kfree(sun50i_domain); +} + +static int sun50i_iommu_attach_domain(struct sun50i_iommu *iommu, + struct sun50i_iommu_domain *sun50i_domain) +{ + iommu->domain = &sun50i_domain->domain; + sun50i_domain->iommu = iommu; + + sun50i_domain->dt_dma = dma_map_single(iommu->dev, sun50i_domain->dt, + DT_SIZE, DMA_TO_DEVICE); + if (dma_mapping_error(iommu->dev, sun50i_domain->dt_dma)) { + dev_err(iommu->dev, "Couldn't map L1 Page Table\n"); + return -ENOMEM; + } + + return sun50i_iommu_enable(iommu); +} + +static void sun50i_iommu_detach_domain(struct sun50i_iommu *iommu, + struct sun50i_iommu_domain *sun50i_domain) +{ + unsigned int i; + + for (i = 0; i < NUM_DT_ENTRIES; i++) { + phys_addr_t pt_phys; + u32 *page_table; + u32 *dte_addr; + u32 dte; + + dte_addr = &sun50i_domain->dt[i]; + dte = *dte_addr; + if (!sun50i_dte_is_pt_valid(dte)) + continue; + + memset(dte_addr, 0, sizeof(*dte_addr)); + sun50i_table_flush(sun50i_domain, dte_addr, 1); + + pt_phys = sun50i_dte_get_pt_address(dte); + page_table = phys_to_virt(pt_phys); + sun50i_iommu_free_page_table(iommu, page_table); + } + + + sun50i_iommu_disable(iommu); + + dma_unmap_single(iommu->dev, virt_to_phys(sun50i_domain->dt), + DT_SIZE, DMA_TO_DEVICE); + + iommu->domain = NULL; +} + +static void sun50i_iommu_detach_device(struct iommu_domain *domain, + struct device *dev) +{ + struct sun50i_iommu_domain *sun50i_domain = to_sun50i_domain(domain); + struct sun50i_iommu *iommu = dev_iommu_priv_get(dev); + + dev_dbg(dev, "Detaching from IOMMU domain\n"); + + if (iommu->domain != domain) + return; + + if (refcount_dec_and_test(&sun50i_domain->refcnt)) + sun50i_iommu_detach_domain(iommu, sun50i_domain); +} + +static int sun50i_iommu_attach_device(struct iommu_domain *domain, + struct device *dev) +{ + struct sun50i_iommu_domain *sun50i_domain = to_sun50i_domain(domain); + struct sun50i_iommu *iommu; + + iommu = sun50i_iommu_from_dev(dev); + if (!iommu) + return -ENODEV; + + dev_dbg(dev, "Attaching to IOMMU domain\n"); + + refcount_inc(&sun50i_domain->refcnt); + + if (iommu->domain == domain) + return 0; + + if (iommu->domain) + sun50i_iommu_detach_device(iommu->domain, dev); + + sun50i_iommu_attach_domain(iommu, sun50i_domain); + + return 0; +} + +static struct iommu_device *sun50i_iommu_probe_device(struct device *dev) +{ + struct sun50i_iommu *iommu; + + iommu = sun50i_iommu_from_dev(dev); + if (!iommu) + return ERR_PTR(-ENODEV); + + return &iommu->iommu; +} + +static struct iommu_group *sun50i_iommu_device_group(struct device *dev) +{ + struct sun50i_iommu *iommu = sun50i_iommu_from_dev(dev); + + return iommu_group_ref_get(iommu->group); +} + +static int sun50i_iommu_of_xlate(struct device *dev, + struct of_phandle_args *args) +{ + struct platform_device *iommu_pdev = of_find_device_by_node(args->np); + unsigned id = args->args[0]; + + dev_iommu_priv_set(dev, platform_get_drvdata(iommu_pdev)); + + return iommu_fwspec_add_ids(dev, &id, 1); +} + +static const struct iommu_ops sun50i_iommu_ops = { + .pgsize_bitmap = SZ_4K, + .device_group = sun50i_iommu_device_group, + .domain_alloc = sun50i_iommu_domain_alloc, + .of_xlate = sun50i_iommu_of_xlate, + .probe_device = sun50i_iommu_probe_device, + .default_domain_ops = &(const struct iommu_domain_ops) { + .attach_dev = sun50i_iommu_attach_device, + .detach_dev = sun50i_iommu_detach_device, + .flush_iotlb_all = sun50i_iommu_flush_iotlb_all, + .iotlb_sync_map = sun50i_iommu_iotlb_sync_map, + .iotlb_sync = sun50i_iommu_iotlb_sync, + .iova_to_phys = sun50i_iommu_iova_to_phys, + .map = sun50i_iommu_map, + .unmap = sun50i_iommu_unmap, + .free = sun50i_iommu_domain_free, + } +}; + +static void sun50i_iommu_report_fault(struct sun50i_iommu *iommu, + unsigned master, phys_addr_t iova, + unsigned prot) +{ + dev_err(iommu->dev, "Page fault for %pad (master %d, dir %s)\n", + &iova, master, (prot == IOMMU_FAULT_WRITE) ? "wr" : "rd"); + + if (iommu->domain) + report_iommu_fault(iommu->domain, iommu->dev, iova, prot); + else + dev_err(iommu->dev, "Page fault while iommu not attached to any domain?\n"); + + sun50i_iommu_zap_range(iommu, iova, SPAGE_SIZE); +} + +static phys_addr_t sun50i_iommu_handle_pt_irq(struct sun50i_iommu *iommu, + unsigned addr_reg, + unsigned blame_reg) +{ + phys_addr_t iova; + unsigned master; + u32 blame; + + assert_spin_locked(&iommu->iommu_lock); + + iova = iommu_read(iommu, addr_reg); + blame = iommu_read(iommu, blame_reg); + master = ilog2(blame & IOMMU_INT_MASTER_MASK); + + /* + * If the address is not in the page table, we can't get what + * operation triggered the fault. Assume it's a read + * operation. + */ + sun50i_iommu_report_fault(iommu, master, iova, IOMMU_FAULT_READ); + + return iova; +} + +static phys_addr_t sun50i_iommu_handle_perm_irq(struct sun50i_iommu *iommu) +{ + enum sun50i_iommu_aci aci; + phys_addr_t iova; + unsigned master; + unsigned dir; + u32 blame; + + assert_spin_locked(&iommu->iommu_lock); + + blame = iommu_read(iommu, IOMMU_INT_STA_REG); + master = ilog2(blame & IOMMU_INT_MASTER_MASK); + iova = iommu_read(iommu, IOMMU_INT_ERR_ADDR_REG(master)); + aci = sun50i_get_pte_aci(iommu_read(iommu, + IOMMU_INT_ERR_DATA_REG(master))); + + switch (aci) { + /* + * If we are in the read-only domain, then it means we + * tried to write. + */ + case SUN50I_IOMMU_ACI_RD: + dir = IOMMU_FAULT_WRITE; + break; + + /* + * If we are in the write-only domain, then it means + * we tried to read. + */ + case SUN50I_IOMMU_ACI_WR: + + /* + * If we are in the domain without any permission, we + * can't really tell. Let's default to a read + * operation. + */ + case SUN50I_IOMMU_ACI_NONE: + + /* WTF? */ + case SUN50I_IOMMU_ACI_RD_WR: + default: + dir = IOMMU_FAULT_READ; + break; + } + + /* + * If the address is not in the page table, we can't get what + * operation triggered the fault. Assume it's a read + * operation. + */ + sun50i_iommu_report_fault(iommu, master, iova, dir); + + return iova; +} + +static irqreturn_t sun50i_iommu_irq(int irq, void *dev_id) +{ + u32 status, l1_status, l2_status, resets; + struct sun50i_iommu *iommu = dev_id; + + spin_lock(&iommu->iommu_lock); + + status = iommu_read(iommu, IOMMU_INT_STA_REG); + if (!(status & IOMMU_INT_MASK)) { + spin_unlock(&iommu->iommu_lock); + return IRQ_NONE; + } + + l1_status = iommu_read(iommu, IOMMU_L1PG_INT_REG); + l2_status = iommu_read(iommu, IOMMU_L2PG_INT_REG); + + if (status & IOMMU_INT_INVALID_L2PG) + sun50i_iommu_handle_pt_irq(iommu, + IOMMU_INT_ERR_ADDR_L2_REG, + IOMMU_L2PG_INT_REG); + else if (status & IOMMU_INT_INVALID_L1PG) + sun50i_iommu_handle_pt_irq(iommu, + IOMMU_INT_ERR_ADDR_L1_REG, + IOMMU_L1PG_INT_REG); + else + sun50i_iommu_handle_perm_irq(iommu); + + iommu_write(iommu, IOMMU_INT_CLR_REG, status); + + resets = (status | l1_status | l2_status) & IOMMU_INT_MASTER_MASK; + iommu_write(iommu, IOMMU_RESET_REG, ~resets); + iommu_write(iommu, IOMMU_RESET_REG, IOMMU_RESET_RELEASE_ALL); + + spin_unlock(&iommu->iommu_lock); + + return IRQ_HANDLED; +} + +static int sun50i_iommu_probe(struct platform_device *pdev) +{ + struct sun50i_iommu *iommu; + int ret, irq; + + iommu = devm_kzalloc(&pdev->dev, sizeof(*iommu), GFP_KERNEL); + if (!iommu) + return -ENOMEM; + spin_lock_init(&iommu->iommu_lock); + platform_set_drvdata(pdev, iommu); + iommu->dev = &pdev->dev; + + iommu->pt_pool = kmem_cache_create(dev_name(&pdev->dev), + PT_SIZE, PT_SIZE, + SLAB_HWCACHE_ALIGN, + NULL); + if (!iommu->pt_pool) + return -ENOMEM; + + iommu->group = iommu_group_alloc(); + if (IS_ERR(iommu->group)) { + ret = PTR_ERR(iommu->group); + goto err_free_cache; + } + + iommu->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(iommu->base)) { + ret = PTR_ERR(iommu->base); + goto err_free_group; + } + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + ret = irq; + goto err_free_group; + } + + iommu->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(iommu->clk)) { + dev_err(&pdev->dev, "Couldn't get our clock.\n"); + ret = PTR_ERR(iommu->clk); + goto err_free_group; + } + + iommu->reset = devm_reset_control_get(&pdev->dev, NULL); + if (IS_ERR(iommu->reset)) { + dev_err(&pdev->dev, "Couldn't get our reset line.\n"); + ret = PTR_ERR(iommu->reset); + goto err_free_group; + } + + ret = iommu_device_sysfs_add(&iommu->iommu, &pdev->dev, + NULL, dev_name(&pdev->dev)); + if (ret) + goto err_free_group; + + ret = iommu_device_register(&iommu->iommu, &sun50i_iommu_ops, &pdev->dev); + if (ret) + goto err_remove_sysfs; + + ret = devm_request_irq(&pdev->dev, irq, sun50i_iommu_irq, 0, + dev_name(&pdev->dev), iommu); + if (ret < 0) + goto err_unregister; + + return 0; + +err_unregister: + iommu_device_unregister(&iommu->iommu); + +err_remove_sysfs: + iommu_device_sysfs_remove(&iommu->iommu); + +err_free_group: + iommu_group_put(iommu->group); + +err_free_cache: + kmem_cache_destroy(iommu->pt_pool); + + return ret; +} + +static const struct of_device_id sun50i_iommu_dt[] = { + { .compatible = "allwinner,sun50i-h6-iommu", }, + { /* sentinel */ }, +}; +MODULE_DEVICE_TABLE(of, sun50i_iommu_dt); + +static struct platform_driver sun50i_iommu_driver = { + .driver = { + .name = "sun50i-iommu", + .of_match_table = sun50i_iommu_dt, + .suppress_bind_attrs = true, + } +}; +builtin_platform_driver_probe(sun50i_iommu_driver, sun50i_iommu_probe); + +MODULE_DESCRIPTION("Allwinner H6 IOMMU driver"); +MODULE_AUTHOR("Maxime Ripard <maxime@cerno.tech>"); +MODULE_AUTHOR("zhuxianbin <zhuxianbin@allwinnertech.com>"); +MODULE_LICENSE("Dual BSD/GPL"); |