diff options
Diffstat (limited to 'drivers/iommu/io-pgtable-arm.c')
-rw-r--r-- | drivers/iommu/io-pgtable-arm.c | 1250 |
1 files changed, 1250 insertions, 0 deletions
diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c new file mode 100644 index 000000000..e1cd31c0e --- /dev/null +++ b/drivers/iommu/io-pgtable-arm.c @@ -0,0 +1,1250 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * CPU-agnostic ARM page table allocator. + * + * Copyright (C) 2014 ARM Limited + * + * Author: Will Deacon <will.deacon@arm.com> + */ + +#define pr_fmt(fmt) "arm-lpae io-pgtable: " fmt + +#include <linux/atomic.h> +#include <linux/bitops.h> +#include <linux/io-pgtable.h> +#include <linux/kernel.h> +#include <linux/sizes.h> +#include <linux/slab.h> +#include <linux/types.h> +#include <linux/dma-mapping.h> + +#include <asm/barrier.h> + +#include "io-pgtable-arm.h" + +#define ARM_LPAE_MAX_ADDR_BITS 52 +#define ARM_LPAE_S2_MAX_CONCAT_PAGES 16 +#define ARM_LPAE_MAX_LEVELS 4 + +/* Struct accessors */ +#define io_pgtable_to_data(x) \ + container_of((x), struct arm_lpae_io_pgtable, iop) + +#define io_pgtable_ops_to_data(x) \ + io_pgtable_to_data(io_pgtable_ops_to_pgtable(x)) + +/* + * Calculate the right shift amount to get to the portion describing level l + * in a virtual address mapped by the pagetable in d. + */ +#define ARM_LPAE_LVL_SHIFT(l,d) \ + (((ARM_LPAE_MAX_LEVELS - (l)) * (d)->bits_per_level) + \ + ilog2(sizeof(arm_lpae_iopte))) + +#define ARM_LPAE_GRANULE(d) \ + (sizeof(arm_lpae_iopte) << (d)->bits_per_level) +#define ARM_LPAE_PGD_SIZE(d) \ + (sizeof(arm_lpae_iopte) << (d)->pgd_bits) + +/* + * Calculate the index at level l used to map virtual address a using the + * pagetable in d. + */ +#define ARM_LPAE_PGD_IDX(l,d) \ + ((l) == (d)->start_level ? (d)->pgd_bits - (d)->bits_per_level : 0) + +#define ARM_LPAE_LVL_IDX(a,l,d) \ + (((u64)(a) >> ARM_LPAE_LVL_SHIFT(l,d)) & \ + ((1 << ((d)->bits_per_level + ARM_LPAE_PGD_IDX(l,d))) - 1)) + +/* Calculate the block/page mapping size at level l for pagetable in d. */ +#define ARM_LPAE_BLOCK_SIZE(l,d) (1ULL << ARM_LPAE_LVL_SHIFT(l,d)) + +/* Page table bits */ +#define ARM_LPAE_PTE_TYPE_SHIFT 0 +#define ARM_LPAE_PTE_TYPE_MASK 0x3 + +#define ARM_LPAE_PTE_TYPE_BLOCK 1 +#define ARM_LPAE_PTE_TYPE_TABLE 3 +#define ARM_LPAE_PTE_TYPE_PAGE 3 + +#define ARM_LPAE_PTE_ADDR_MASK GENMASK_ULL(47,12) + +#define ARM_LPAE_PTE_NSTABLE (((arm_lpae_iopte)1) << 63) +#define ARM_LPAE_PTE_XN (((arm_lpae_iopte)3) << 53) +#define ARM_LPAE_PTE_AF (((arm_lpae_iopte)1) << 10) +#define ARM_LPAE_PTE_SH_NS (((arm_lpae_iopte)0) << 8) +#define ARM_LPAE_PTE_SH_OS (((arm_lpae_iopte)2) << 8) +#define ARM_LPAE_PTE_SH_IS (((arm_lpae_iopte)3) << 8) +#define ARM_LPAE_PTE_NS (((arm_lpae_iopte)1) << 5) +#define ARM_LPAE_PTE_VALID (((arm_lpae_iopte)1) << 0) + +#define ARM_LPAE_PTE_ATTR_LO_MASK (((arm_lpae_iopte)0x3ff) << 2) +/* Ignore the contiguous bit for block splitting */ +#define ARM_LPAE_PTE_ATTR_HI_MASK (((arm_lpae_iopte)6) << 52) +#define ARM_LPAE_PTE_ATTR_MASK (ARM_LPAE_PTE_ATTR_LO_MASK | \ + ARM_LPAE_PTE_ATTR_HI_MASK) +/* Software bit for solving coherency races */ +#define ARM_LPAE_PTE_SW_SYNC (((arm_lpae_iopte)1) << 55) + +/* Stage-1 PTE */ +#define ARM_LPAE_PTE_AP_UNPRIV (((arm_lpae_iopte)1) << 6) +#define ARM_LPAE_PTE_AP_RDONLY (((arm_lpae_iopte)2) << 6) +#define ARM_LPAE_PTE_ATTRINDX_SHIFT 2 +#define ARM_LPAE_PTE_nG (((arm_lpae_iopte)1) << 11) + +/* Stage-2 PTE */ +#define ARM_LPAE_PTE_HAP_FAULT (((arm_lpae_iopte)0) << 6) +#define ARM_LPAE_PTE_HAP_READ (((arm_lpae_iopte)1) << 6) +#define ARM_LPAE_PTE_HAP_WRITE (((arm_lpae_iopte)2) << 6) +#define ARM_LPAE_PTE_MEMATTR_OIWB (((arm_lpae_iopte)0xf) << 2) +#define ARM_LPAE_PTE_MEMATTR_NC (((arm_lpae_iopte)0x5) << 2) +#define ARM_LPAE_PTE_MEMATTR_DEV (((arm_lpae_iopte)0x1) << 2) + +/* Register bits */ +#define ARM_LPAE_VTCR_SL0_MASK 0x3 + +#define ARM_LPAE_TCR_T0SZ_SHIFT 0 + +#define ARM_LPAE_VTCR_PS_SHIFT 16 +#define ARM_LPAE_VTCR_PS_MASK 0x7 + +#define ARM_LPAE_MAIR_ATTR_SHIFT(n) ((n) << 3) +#define ARM_LPAE_MAIR_ATTR_MASK 0xff +#define ARM_LPAE_MAIR_ATTR_DEVICE 0x04 +#define ARM_LPAE_MAIR_ATTR_NC 0x44 +#define ARM_LPAE_MAIR_ATTR_INC_OWBRWA 0xf4 +#define ARM_LPAE_MAIR_ATTR_WBRWA 0xff +#define ARM_LPAE_MAIR_ATTR_IDX_NC 0 +#define ARM_LPAE_MAIR_ATTR_IDX_CACHE 1 +#define ARM_LPAE_MAIR_ATTR_IDX_DEV 2 +#define ARM_LPAE_MAIR_ATTR_IDX_INC_OCACHE 3 + +#define ARM_MALI_LPAE_TTBR_ADRMODE_TABLE (3u << 0) +#define ARM_MALI_LPAE_TTBR_READ_INNER BIT(2) +#define ARM_MALI_LPAE_TTBR_SHARE_OUTER BIT(4) + +#define ARM_MALI_LPAE_MEMATTR_IMP_DEF 0x88ULL +#define ARM_MALI_LPAE_MEMATTR_WRITE_ALLOC 0x8DULL + +/* IOPTE accessors */ +#define iopte_deref(pte,d) __va(iopte_to_paddr(pte, d)) + +#define iopte_type(pte,l) \ + (((pte) >> ARM_LPAE_PTE_TYPE_SHIFT) & ARM_LPAE_PTE_TYPE_MASK) + +#define iopte_prot(pte) ((pte) & ARM_LPAE_PTE_ATTR_MASK) + +struct arm_lpae_io_pgtable { + struct io_pgtable iop; + + int pgd_bits; + int start_level; + int bits_per_level; + + void *pgd; +}; + +typedef u64 arm_lpae_iopte; + +static inline bool iopte_leaf(arm_lpae_iopte pte, int lvl, + enum io_pgtable_fmt fmt) +{ + if (lvl == (ARM_LPAE_MAX_LEVELS - 1) && fmt != ARM_MALI_LPAE) + return iopte_type(pte, lvl) == ARM_LPAE_PTE_TYPE_PAGE; + + return iopte_type(pte, lvl) == ARM_LPAE_PTE_TYPE_BLOCK; +} + +static arm_lpae_iopte paddr_to_iopte(phys_addr_t paddr, + struct arm_lpae_io_pgtable *data) +{ + arm_lpae_iopte pte = paddr; + + /* Of the bits which overlap, either 51:48 or 15:12 are always RES0 */ + return (pte | (pte >> (48 - 12))) & ARM_LPAE_PTE_ADDR_MASK; +} + +static phys_addr_t iopte_to_paddr(arm_lpae_iopte pte, + struct arm_lpae_io_pgtable *data) +{ + u64 paddr = pte & ARM_LPAE_PTE_ADDR_MASK; + + if (ARM_LPAE_GRANULE(data) < SZ_64K) + return paddr; + + /* Rotate the packed high-order bits back to the top */ + return (paddr | (paddr << (48 - 12))) & (ARM_LPAE_PTE_ADDR_MASK << 4); +} + +static bool selftest_running = false; + +static dma_addr_t __arm_lpae_dma_addr(void *pages) +{ + return (dma_addr_t)virt_to_phys(pages); +} + +static void *__arm_lpae_alloc_pages(size_t size, gfp_t gfp, + struct io_pgtable_cfg *cfg) +{ + struct device *dev = cfg->iommu_dev; + int order = get_order(size); + struct page *p; + dma_addr_t dma; + void *pages; + + VM_BUG_ON((gfp & __GFP_HIGHMEM)); + p = alloc_pages_node(dev ? dev_to_node(dev) : NUMA_NO_NODE, + gfp | __GFP_ZERO, order); + if (!p) + return NULL; + + pages = page_address(p); + if (!cfg->coherent_walk) { + dma = dma_map_single(dev, pages, size, DMA_TO_DEVICE); + if (dma_mapping_error(dev, dma)) + goto out_free; + /* + * We depend on the IOMMU being able to work with any physical + * address directly, so if the DMA layer suggests otherwise by + * translating or truncating them, that bodes very badly... + */ + if (dma != virt_to_phys(pages)) + goto out_unmap; + } + + return pages; + +out_unmap: + dev_err(dev, "Cannot accommodate DMA translation for IOMMU page tables\n"); + dma_unmap_single(dev, dma, size, DMA_TO_DEVICE); +out_free: + __free_pages(p, order); + return NULL; +} + +static void __arm_lpae_free_pages(void *pages, size_t size, + struct io_pgtable_cfg *cfg) +{ + if (!cfg->coherent_walk) + dma_unmap_single(cfg->iommu_dev, __arm_lpae_dma_addr(pages), + size, DMA_TO_DEVICE); + free_pages((unsigned long)pages, get_order(size)); +} + +static void __arm_lpae_sync_pte(arm_lpae_iopte *ptep, + struct io_pgtable_cfg *cfg) +{ + dma_sync_single_for_device(cfg->iommu_dev, __arm_lpae_dma_addr(ptep), + sizeof(*ptep), DMA_TO_DEVICE); +} + +static void __arm_lpae_set_pte(arm_lpae_iopte *ptep, arm_lpae_iopte pte, + struct io_pgtable_cfg *cfg) +{ + *ptep = pte; + + if (!cfg->coherent_walk) + __arm_lpae_sync_pte(ptep, cfg); +} + +static size_t __arm_lpae_unmap(struct arm_lpae_io_pgtable *data, + struct iommu_iotlb_gather *gather, + unsigned long iova, size_t size, int lvl, + arm_lpae_iopte *ptep); + +static void __arm_lpae_init_pte(struct arm_lpae_io_pgtable *data, + phys_addr_t paddr, arm_lpae_iopte prot, + int lvl, arm_lpae_iopte *ptep) +{ + arm_lpae_iopte pte = prot; + + if (data->iop.fmt != ARM_MALI_LPAE && lvl == ARM_LPAE_MAX_LEVELS - 1) + pte |= ARM_LPAE_PTE_TYPE_PAGE; + else + pte |= ARM_LPAE_PTE_TYPE_BLOCK; + + pte |= paddr_to_iopte(paddr, data); + + __arm_lpae_set_pte(ptep, pte, &data->iop.cfg); +} + +static int arm_lpae_init_pte(struct arm_lpae_io_pgtable *data, + unsigned long iova, phys_addr_t paddr, + arm_lpae_iopte prot, int lvl, + arm_lpae_iopte *ptep) +{ + arm_lpae_iopte pte = *ptep; + + if (iopte_leaf(pte, lvl, data->iop.fmt)) { + /* We require an unmap first */ + WARN_ON(!selftest_running); + return -EEXIST; + } else if (iopte_type(pte, lvl) == ARM_LPAE_PTE_TYPE_TABLE) { + /* + * We need to unmap and free the old table before + * overwriting it with a block entry. + */ + arm_lpae_iopte *tblp; + size_t sz = ARM_LPAE_BLOCK_SIZE(lvl, data); + + tblp = ptep - ARM_LPAE_LVL_IDX(iova, lvl, data); + if (__arm_lpae_unmap(data, NULL, iova, sz, lvl, tblp) != sz) { + WARN_ON(1); + return -EINVAL; + } + } + + __arm_lpae_init_pte(data, paddr, prot, lvl, ptep); + return 0; +} + +static arm_lpae_iopte arm_lpae_install_table(arm_lpae_iopte *table, + arm_lpae_iopte *ptep, + arm_lpae_iopte curr, + struct arm_lpae_io_pgtable *data) +{ + arm_lpae_iopte old, new; + struct io_pgtable_cfg *cfg = &data->iop.cfg; + + new = paddr_to_iopte(__pa(table), data) | ARM_LPAE_PTE_TYPE_TABLE; + if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_NS) + new |= ARM_LPAE_PTE_NSTABLE; + + /* + * Ensure the table itself is visible before its PTE can be. + * Whilst we could get away with cmpxchg64_release below, this + * doesn't have any ordering semantics when !CONFIG_SMP. + */ + dma_wmb(); + + old = cmpxchg64_relaxed(ptep, curr, new); + + if (cfg->coherent_walk || (old & ARM_LPAE_PTE_SW_SYNC)) + return old; + + /* Even if it's not ours, there's no point waiting; just kick it */ + __arm_lpae_sync_pte(ptep, cfg); + if (old == curr) + WRITE_ONCE(*ptep, new | ARM_LPAE_PTE_SW_SYNC); + + return old; +} + +static int __arm_lpae_map(struct arm_lpae_io_pgtable *data, unsigned long iova, + phys_addr_t paddr, size_t size, arm_lpae_iopte prot, + int lvl, arm_lpae_iopte *ptep, gfp_t gfp) +{ + arm_lpae_iopte *cptep, pte; + size_t block_size = ARM_LPAE_BLOCK_SIZE(lvl, data); + size_t tblsz = ARM_LPAE_GRANULE(data); + struct io_pgtable_cfg *cfg = &data->iop.cfg; + + /* Find our entry at the current level */ + ptep += ARM_LPAE_LVL_IDX(iova, lvl, data); + + /* If we can install a leaf entry at this level, then do so */ + if (size == block_size) + return arm_lpae_init_pte(data, iova, paddr, prot, lvl, ptep); + + /* We can't allocate tables at the final level */ + if (WARN_ON(lvl >= ARM_LPAE_MAX_LEVELS - 1)) + return -EINVAL; + + /* Grab a pointer to the next level */ + pte = READ_ONCE(*ptep); + if (!pte) { + cptep = __arm_lpae_alloc_pages(tblsz, gfp, cfg); + if (!cptep) + return -ENOMEM; + + pte = arm_lpae_install_table(cptep, ptep, 0, data); + if (pte) + __arm_lpae_free_pages(cptep, tblsz, cfg); + } else if (!cfg->coherent_walk && !(pte & ARM_LPAE_PTE_SW_SYNC)) { + __arm_lpae_sync_pte(ptep, cfg); + } + + if (pte && !iopte_leaf(pte, lvl, data->iop.fmt)) { + cptep = iopte_deref(pte, data); + } else if (pte) { + /* We require an unmap first */ + WARN_ON(!selftest_running); + return -EEXIST; + } + + /* Rinse, repeat */ + return __arm_lpae_map(data, iova, paddr, size, prot, lvl + 1, cptep, gfp); +} + +static arm_lpae_iopte arm_lpae_prot_to_pte(struct arm_lpae_io_pgtable *data, + int prot) +{ + arm_lpae_iopte pte; + + if (data->iop.fmt == ARM_64_LPAE_S1 || + data->iop.fmt == ARM_32_LPAE_S1) { + pte = ARM_LPAE_PTE_nG; + if (!(prot & IOMMU_WRITE) && (prot & IOMMU_READ)) + pte |= ARM_LPAE_PTE_AP_RDONLY; + if (!(prot & IOMMU_PRIV)) + pte |= ARM_LPAE_PTE_AP_UNPRIV; + } else { + pte = ARM_LPAE_PTE_HAP_FAULT; + if (prot & IOMMU_READ) + pte |= ARM_LPAE_PTE_HAP_READ; + if (prot & IOMMU_WRITE) + pte |= ARM_LPAE_PTE_HAP_WRITE; + } + + /* + * Note that this logic is structured to accommodate Mali LPAE + * having stage-1-like attributes but stage-2-like permissions. + */ + if (data->iop.fmt == ARM_64_LPAE_S2 || + data->iop.fmt == ARM_32_LPAE_S2) { + if (prot & IOMMU_MMIO) + pte |= ARM_LPAE_PTE_MEMATTR_DEV; + else if (prot & IOMMU_CACHE) + pte |= ARM_LPAE_PTE_MEMATTR_OIWB; + else + pte |= ARM_LPAE_PTE_MEMATTR_NC; + } else { + if (prot & IOMMU_MMIO) + pte |= (ARM_LPAE_MAIR_ATTR_IDX_DEV + << ARM_LPAE_PTE_ATTRINDX_SHIFT); + else if (prot & IOMMU_CACHE) + pte |= (ARM_LPAE_MAIR_ATTR_IDX_CACHE + << ARM_LPAE_PTE_ATTRINDX_SHIFT); + } + + /* + * Also Mali has its own notions of shareability wherein its Inner + * domain covers the cores within the GPU, and its Outer domain is + * "outside the GPU" (i.e. either the Inner or System domain in CPU + * terms, depending on coherency). + */ + if (prot & IOMMU_CACHE && data->iop.fmt != ARM_MALI_LPAE) + pte |= ARM_LPAE_PTE_SH_IS; + else + pte |= ARM_LPAE_PTE_SH_OS; + + if (prot & IOMMU_NOEXEC) + pte |= ARM_LPAE_PTE_XN; + + if (data->iop.cfg.quirks & IO_PGTABLE_QUIRK_ARM_NS) + pte |= ARM_LPAE_PTE_NS; + + if (data->iop.fmt != ARM_MALI_LPAE) + pte |= ARM_LPAE_PTE_AF; + + return pte; +} + +static int arm_lpae_map(struct io_pgtable_ops *ops, unsigned long iova, + phys_addr_t paddr, size_t size, int iommu_prot, gfp_t gfp) +{ + struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops); + struct io_pgtable_cfg *cfg = &data->iop.cfg; + arm_lpae_iopte *ptep = data->pgd; + int ret, lvl = data->start_level; + arm_lpae_iopte prot; + long iaext = (s64)iova >> cfg->ias; + + /* If no access, then nothing to do */ + if (!(iommu_prot & (IOMMU_READ | IOMMU_WRITE))) + return 0; + + if (WARN_ON(!size || (size & cfg->pgsize_bitmap) != size)) + return -EINVAL; + + if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_TTBR1) + iaext = ~iaext; + if (WARN_ON(iaext || paddr >> cfg->oas)) + return -ERANGE; + + prot = arm_lpae_prot_to_pte(data, iommu_prot); + ret = __arm_lpae_map(data, iova, paddr, size, prot, lvl, ptep, gfp); + /* + * Synchronise all PTE updates for the new mapping before there's + * a chance for anything to kick off a table walk for the new iova. + */ + wmb(); + + return ret; +} + +static void __arm_lpae_free_pgtable(struct arm_lpae_io_pgtable *data, int lvl, + arm_lpae_iopte *ptep) +{ + arm_lpae_iopte *start, *end; + unsigned long table_size; + + if (lvl == data->start_level) + table_size = ARM_LPAE_PGD_SIZE(data); + else + table_size = ARM_LPAE_GRANULE(data); + + start = ptep; + + /* Only leaf entries at the last level */ + if (lvl == ARM_LPAE_MAX_LEVELS - 1) + end = ptep; + else + end = (void *)ptep + table_size; + + while (ptep != end) { + arm_lpae_iopte pte = *ptep++; + + if (!pte || iopte_leaf(pte, lvl, data->iop.fmt)) + continue; + + __arm_lpae_free_pgtable(data, lvl + 1, iopte_deref(pte, data)); + } + + __arm_lpae_free_pages(start, table_size, &data->iop.cfg); +} + +static void arm_lpae_free_pgtable(struct io_pgtable *iop) +{ + struct arm_lpae_io_pgtable *data = io_pgtable_to_data(iop); + + __arm_lpae_free_pgtable(data, data->start_level, data->pgd); + kfree(data); +} + +static size_t arm_lpae_split_blk_unmap(struct arm_lpae_io_pgtable *data, + struct iommu_iotlb_gather *gather, + unsigned long iova, size_t size, + arm_lpae_iopte blk_pte, int lvl, + arm_lpae_iopte *ptep) +{ + struct io_pgtable_cfg *cfg = &data->iop.cfg; + arm_lpae_iopte pte, *tablep; + phys_addr_t blk_paddr; + size_t tablesz = ARM_LPAE_GRANULE(data); + size_t split_sz = ARM_LPAE_BLOCK_SIZE(lvl, data); + int i, unmap_idx = -1; + + if (WARN_ON(lvl == ARM_LPAE_MAX_LEVELS)) + return 0; + + tablep = __arm_lpae_alloc_pages(tablesz, GFP_ATOMIC, cfg); + if (!tablep) + return 0; /* Bytes unmapped */ + + if (size == split_sz) + unmap_idx = ARM_LPAE_LVL_IDX(iova, lvl, data); + + blk_paddr = iopte_to_paddr(blk_pte, data); + pte = iopte_prot(blk_pte); + + for (i = 0; i < tablesz / sizeof(pte); i++, blk_paddr += split_sz) { + /* Unmap! */ + if (i == unmap_idx) + continue; + + __arm_lpae_init_pte(data, blk_paddr, pte, lvl, &tablep[i]); + } + + pte = arm_lpae_install_table(tablep, ptep, blk_pte, data); + if (pte != blk_pte) { + __arm_lpae_free_pages(tablep, tablesz, cfg); + /* + * We may race against someone unmapping another part of this + * block, but anything else is invalid. We can't misinterpret + * a page entry here since we're never at the last level. + */ + if (iopte_type(pte, lvl - 1) != ARM_LPAE_PTE_TYPE_TABLE) + return 0; + + tablep = iopte_deref(pte, data); + } else if (unmap_idx >= 0) { + io_pgtable_tlb_add_page(&data->iop, gather, iova, size); + return size; + } + + return __arm_lpae_unmap(data, gather, iova, size, lvl, tablep); +} + +static size_t __arm_lpae_unmap(struct arm_lpae_io_pgtable *data, + struct iommu_iotlb_gather *gather, + unsigned long iova, size_t size, int lvl, + arm_lpae_iopte *ptep) +{ + arm_lpae_iopte pte; + struct io_pgtable *iop = &data->iop; + + /* Something went horribly wrong and we ran out of page table */ + if (WARN_ON(lvl == ARM_LPAE_MAX_LEVELS)) + return 0; + + ptep += ARM_LPAE_LVL_IDX(iova, lvl, data); + pte = READ_ONCE(*ptep); + if (WARN_ON(!pte)) + return 0; + + /* If the size matches this level, we're in the right place */ + if (size == ARM_LPAE_BLOCK_SIZE(lvl, data)) { + __arm_lpae_set_pte(ptep, 0, &iop->cfg); + + if (!iopte_leaf(pte, lvl, iop->fmt)) { + /* Also flush any partial walks */ + io_pgtable_tlb_flush_walk(iop, iova, size, + ARM_LPAE_GRANULE(data)); + ptep = iopte_deref(pte, data); + __arm_lpae_free_pgtable(data, lvl + 1, ptep); + } else if (iop->cfg.quirks & IO_PGTABLE_QUIRK_NON_STRICT) { + /* + * Order the PTE update against queueing the IOVA, to + * guarantee that a flush callback from a different CPU + * has observed it before the TLBIALL can be issued. + */ + smp_wmb(); + } else { + io_pgtable_tlb_add_page(iop, gather, iova, size); + } + + return size; + } else if (iopte_leaf(pte, lvl, iop->fmt)) { + /* + * Insert a table at the next level to map the old region, + * minus the part we want to unmap + */ + return arm_lpae_split_blk_unmap(data, gather, iova, size, pte, + lvl + 1, ptep); + } + + /* Keep on walkin' */ + ptep = iopte_deref(pte, data); + return __arm_lpae_unmap(data, gather, iova, size, lvl + 1, ptep); +} + +static size_t arm_lpae_unmap(struct io_pgtable_ops *ops, unsigned long iova, + size_t size, struct iommu_iotlb_gather *gather) +{ + struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops); + struct io_pgtable_cfg *cfg = &data->iop.cfg; + arm_lpae_iopte *ptep = data->pgd; + long iaext = (s64)iova >> cfg->ias; + + if (WARN_ON(!size || (size & cfg->pgsize_bitmap) != size)) + return 0; + + if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_TTBR1) + iaext = ~iaext; + if (WARN_ON(iaext)) + return 0; + + return __arm_lpae_unmap(data, gather, iova, size, data->start_level, ptep); +} + +static phys_addr_t arm_lpae_iova_to_phys(struct io_pgtable_ops *ops, + unsigned long iova) +{ + struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops); + arm_lpae_iopte pte, *ptep = data->pgd; + int lvl = data->start_level; + + do { + /* Valid IOPTE pointer? */ + if (!ptep) + return 0; + + /* Grab the IOPTE we're interested in */ + ptep += ARM_LPAE_LVL_IDX(iova, lvl, data); + pte = READ_ONCE(*ptep); + + /* Valid entry? */ + if (!pte) + return 0; + + /* Leaf entry? */ + if (iopte_leaf(pte, lvl, data->iop.fmt)) + goto found_translation; + + /* Take it to the next level */ + ptep = iopte_deref(pte, data); + } while (++lvl < ARM_LPAE_MAX_LEVELS); + + /* Ran out of page tables to walk */ + return 0; + +found_translation: + iova &= (ARM_LPAE_BLOCK_SIZE(lvl, data) - 1); + return iopte_to_paddr(pte, data) | iova; +} + +static void arm_lpae_restrict_pgsizes(struct io_pgtable_cfg *cfg) +{ + unsigned long granule, page_sizes; + unsigned int max_addr_bits = 48; + + /* + * We need to restrict the supported page sizes to match the + * translation regime for a particular granule. Aim to match + * the CPU page size if possible, otherwise prefer smaller sizes. + * While we're at it, restrict the block sizes to match the + * chosen granule. + */ + if (cfg->pgsize_bitmap & PAGE_SIZE) + granule = PAGE_SIZE; + else if (cfg->pgsize_bitmap & ~PAGE_MASK) + granule = 1UL << __fls(cfg->pgsize_bitmap & ~PAGE_MASK); + else if (cfg->pgsize_bitmap & PAGE_MASK) + granule = 1UL << __ffs(cfg->pgsize_bitmap & PAGE_MASK); + else + granule = 0; + + switch (granule) { + case SZ_4K: + page_sizes = (SZ_4K | SZ_2M | SZ_1G); + break; + case SZ_16K: + page_sizes = (SZ_16K | SZ_32M); + break; + case SZ_64K: + max_addr_bits = 52; + page_sizes = (SZ_64K | SZ_512M); + if (cfg->oas > 48) + page_sizes |= 1ULL << 42; /* 4TB */ + break; + default: + page_sizes = 0; + } + + cfg->pgsize_bitmap &= page_sizes; + cfg->ias = min(cfg->ias, max_addr_bits); + cfg->oas = min(cfg->oas, max_addr_bits); +} + +static struct arm_lpae_io_pgtable * +arm_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg) +{ + struct arm_lpae_io_pgtable *data; + int levels, va_bits, pg_shift; + + arm_lpae_restrict_pgsizes(cfg); + + if (!(cfg->pgsize_bitmap & (SZ_4K | SZ_16K | SZ_64K))) + return NULL; + + if (cfg->ias > ARM_LPAE_MAX_ADDR_BITS) + return NULL; + + if (cfg->oas > ARM_LPAE_MAX_ADDR_BITS) + return NULL; + + data = kmalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return NULL; + + pg_shift = __ffs(cfg->pgsize_bitmap); + data->bits_per_level = pg_shift - ilog2(sizeof(arm_lpae_iopte)); + + va_bits = cfg->ias - pg_shift; + levels = DIV_ROUND_UP(va_bits, data->bits_per_level); + data->start_level = ARM_LPAE_MAX_LEVELS - levels; + + /* Calculate the actual size of our pgd (without concatenation) */ + data->pgd_bits = va_bits - (data->bits_per_level * (levels - 1)); + + data->iop.ops = (struct io_pgtable_ops) { + .map = arm_lpae_map, + .unmap = arm_lpae_unmap, + .iova_to_phys = arm_lpae_iova_to_phys, + }; + + return data; +} + +static struct io_pgtable * +arm_64_lpae_alloc_pgtable_s1(struct io_pgtable_cfg *cfg, void *cookie) +{ + u64 reg; + struct arm_lpae_io_pgtable *data; + typeof(&cfg->arm_lpae_s1_cfg.tcr) tcr = &cfg->arm_lpae_s1_cfg.tcr; + bool tg1; + + if (cfg->quirks & ~(IO_PGTABLE_QUIRK_ARM_NS | + IO_PGTABLE_QUIRK_NON_STRICT | + IO_PGTABLE_QUIRK_ARM_TTBR1)) + return NULL; + + data = arm_lpae_alloc_pgtable(cfg); + if (!data) + return NULL; + + /* TCR */ + if (cfg->coherent_walk) { + tcr->sh = ARM_LPAE_TCR_SH_IS; + tcr->irgn = ARM_LPAE_TCR_RGN_WBWA; + tcr->orgn = ARM_LPAE_TCR_RGN_WBWA; + } else { + tcr->sh = ARM_LPAE_TCR_SH_OS; + tcr->irgn = ARM_LPAE_TCR_RGN_NC; + tcr->orgn = ARM_LPAE_TCR_RGN_NC; + } + + tg1 = cfg->quirks & IO_PGTABLE_QUIRK_ARM_TTBR1; + switch (ARM_LPAE_GRANULE(data)) { + case SZ_4K: + tcr->tg = tg1 ? ARM_LPAE_TCR_TG1_4K : ARM_LPAE_TCR_TG0_4K; + break; + case SZ_16K: + tcr->tg = tg1 ? ARM_LPAE_TCR_TG1_16K : ARM_LPAE_TCR_TG0_16K; + break; + case SZ_64K: + tcr->tg = tg1 ? ARM_LPAE_TCR_TG1_64K : ARM_LPAE_TCR_TG0_64K; + break; + } + + switch (cfg->oas) { + case 32: + tcr->ips = ARM_LPAE_TCR_PS_32_BIT; + break; + case 36: + tcr->ips = ARM_LPAE_TCR_PS_36_BIT; + break; + case 40: + tcr->ips = ARM_LPAE_TCR_PS_40_BIT; + break; + case 42: + tcr->ips = ARM_LPAE_TCR_PS_42_BIT; + break; + case 44: + tcr->ips = ARM_LPAE_TCR_PS_44_BIT; + break; + case 48: + tcr->ips = ARM_LPAE_TCR_PS_48_BIT; + break; + case 52: + tcr->ips = ARM_LPAE_TCR_PS_52_BIT; + break; + default: + goto out_free_data; + } + + tcr->tsz = 64ULL - cfg->ias; + + /* MAIRs */ + reg = (ARM_LPAE_MAIR_ATTR_NC + << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_NC)) | + (ARM_LPAE_MAIR_ATTR_WBRWA + << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_CACHE)) | + (ARM_LPAE_MAIR_ATTR_DEVICE + << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_DEV)) | + (ARM_LPAE_MAIR_ATTR_INC_OWBRWA + << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_INC_OCACHE)); + + cfg->arm_lpae_s1_cfg.mair = reg; + + /* Looking good; allocate a pgd */ + data->pgd = __arm_lpae_alloc_pages(ARM_LPAE_PGD_SIZE(data), + GFP_KERNEL, cfg); + if (!data->pgd) + goto out_free_data; + + /* Ensure the empty pgd is visible before any actual TTBR write */ + wmb(); + + /* TTBR */ + cfg->arm_lpae_s1_cfg.ttbr = virt_to_phys(data->pgd); + return &data->iop; + +out_free_data: + kfree(data); + return NULL; +} + +static struct io_pgtable * +arm_64_lpae_alloc_pgtable_s2(struct io_pgtable_cfg *cfg, void *cookie) +{ + u64 sl; + struct arm_lpae_io_pgtable *data; + typeof(&cfg->arm_lpae_s2_cfg.vtcr) vtcr = &cfg->arm_lpae_s2_cfg.vtcr; + + /* The NS quirk doesn't apply at stage 2 */ + if (cfg->quirks & ~(IO_PGTABLE_QUIRK_NON_STRICT)) + return NULL; + + data = arm_lpae_alloc_pgtable(cfg); + if (!data) + return NULL; + + /* + * Concatenate PGDs at level 1 if possible in order to reduce + * the depth of the stage-2 walk. + */ + if (data->start_level == 0) { + unsigned long pgd_pages; + + pgd_pages = ARM_LPAE_PGD_SIZE(data) / sizeof(arm_lpae_iopte); + if (pgd_pages <= ARM_LPAE_S2_MAX_CONCAT_PAGES) { + data->pgd_bits += data->bits_per_level; + data->start_level++; + } + } + + /* VTCR */ + if (cfg->coherent_walk) { + vtcr->sh = ARM_LPAE_TCR_SH_IS; + vtcr->irgn = ARM_LPAE_TCR_RGN_WBWA; + vtcr->orgn = ARM_LPAE_TCR_RGN_WBWA; + } else { + vtcr->sh = ARM_LPAE_TCR_SH_OS; + vtcr->irgn = ARM_LPAE_TCR_RGN_NC; + vtcr->orgn = ARM_LPAE_TCR_RGN_NC; + } + + sl = data->start_level; + + switch (ARM_LPAE_GRANULE(data)) { + case SZ_4K: + vtcr->tg = ARM_LPAE_TCR_TG0_4K; + sl++; /* SL0 format is different for 4K granule size */ + break; + case SZ_16K: + vtcr->tg = ARM_LPAE_TCR_TG0_16K; + break; + case SZ_64K: + vtcr->tg = ARM_LPAE_TCR_TG0_64K; + break; + } + + switch (cfg->oas) { + case 32: + vtcr->ps = ARM_LPAE_TCR_PS_32_BIT; + break; + case 36: + vtcr->ps = ARM_LPAE_TCR_PS_36_BIT; + break; + case 40: + vtcr->ps = ARM_LPAE_TCR_PS_40_BIT; + break; + case 42: + vtcr->ps = ARM_LPAE_TCR_PS_42_BIT; + break; + case 44: + vtcr->ps = ARM_LPAE_TCR_PS_44_BIT; + break; + case 48: + vtcr->ps = ARM_LPAE_TCR_PS_48_BIT; + break; + case 52: + vtcr->ps = ARM_LPAE_TCR_PS_52_BIT; + break; + default: + goto out_free_data; + } + + vtcr->tsz = 64ULL - cfg->ias; + vtcr->sl = ~sl & ARM_LPAE_VTCR_SL0_MASK; + + /* Allocate pgd pages */ + data->pgd = __arm_lpae_alloc_pages(ARM_LPAE_PGD_SIZE(data), + GFP_KERNEL, cfg); + if (!data->pgd) + goto out_free_data; + + /* Ensure the empty pgd is visible before any actual TTBR write */ + wmb(); + + /* VTTBR */ + cfg->arm_lpae_s2_cfg.vttbr = virt_to_phys(data->pgd); + return &data->iop; + +out_free_data: + kfree(data); + return NULL; +} + +static struct io_pgtable * +arm_32_lpae_alloc_pgtable_s1(struct io_pgtable_cfg *cfg, void *cookie) +{ + if (cfg->ias > 32 || cfg->oas > 40) + return NULL; + + cfg->pgsize_bitmap &= (SZ_4K | SZ_2M | SZ_1G); + return arm_64_lpae_alloc_pgtable_s1(cfg, cookie); +} + +static struct io_pgtable * +arm_32_lpae_alloc_pgtable_s2(struct io_pgtable_cfg *cfg, void *cookie) +{ + if (cfg->ias > 40 || cfg->oas > 40) + return NULL; + + cfg->pgsize_bitmap &= (SZ_4K | SZ_2M | SZ_1G); + return arm_64_lpae_alloc_pgtable_s2(cfg, cookie); +} + +static struct io_pgtable * +arm_mali_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg, void *cookie) +{ + struct arm_lpae_io_pgtable *data; + + /* No quirks for Mali (hopefully) */ + if (cfg->quirks) + return NULL; + + if (cfg->ias > 48 || cfg->oas > 40) + return NULL; + + cfg->pgsize_bitmap &= (SZ_4K | SZ_2M | SZ_1G); + + data = arm_lpae_alloc_pgtable(cfg); + if (!data) + return NULL; + + /* Mali seems to need a full 4-level table regardless of IAS */ + if (data->start_level > 0) { + data->start_level = 0; + data->pgd_bits = 0; + } + /* + * MEMATTR: Mali has no actual notion of a non-cacheable type, so the + * best we can do is mimic the out-of-tree driver and hope that the + * "implementation-defined caching policy" is good enough. Similarly, + * we'll use it for the sake of a valid attribute for our 'device' + * index, although callers should never request that in practice. + */ + cfg->arm_mali_lpae_cfg.memattr = + (ARM_MALI_LPAE_MEMATTR_IMP_DEF + << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_NC)) | + (ARM_MALI_LPAE_MEMATTR_WRITE_ALLOC + << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_CACHE)) | + (ARM_MALI_LPAE_MEMATTR_IMP_DEF + << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_DEV)); + + data->pgd = __arm_lpae_alloc_pages(ARM_LPAE_PGD_SIZE(data), GFP_KERNEL, + cfg); + if (!data->pgd) + goto out_free_data; + + /* Ensure the empty pgd is visible before TRANSTAB can be written */ + wmb(); + + cfg->arm_mali_lpae_cfg.transtab = virt_to_phys(data->pgd) | + ARM_MALI_LPAE_TTBR_READ_INNER | + ARM_MALI_LPAE_TTBR_ADRMODE_TABLE; + if (cfg->coherent_walk) + cfg->arm_mali_lpae_cfg.transtab |= ARM_MALI_LPAE_TTBR_SHARE_OUTER; + + return &data->iop; + +out_free_data: + kfree(data); + return NULL; +} + +struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s1_init_fns = { + .alloc = arm_64_lpae_alloc_pgtable_s1, + .free = arm_lpae_free_pgtable, +}; + +struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s2_init_fns = { + .alloc = arm_64_lpae_alloc_pgtable_s2, + .free = arm_lpae_free_pgtable, +}; + +struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s1_init_fns = { + .alloc = arm_32_lpae_alloc_pgtable_s1, + .free = arm_lpae_free_pgtable, +}; + +struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s2_init_fns = { + .alloc = arm_32_lpae_alloc_pgtable_s2, + .free = arm_lpae_free_pgtable, +}; + +struct io_pgtable_init_fns io_pgtable_arm_mali_lpae_init_fns = { + .alloc = arm_mali_lpae_alloc_pgtable, + .free = arm_lpae_free_pgtable, +}; + +#ifdef CONFIG_IOMMU_IO_PGTABLE_LPAE_SELFTEST + +static struct io_pgtable_cfg *cfg_cookie __initdata; + +static void __init dummy_tlb_flush_all(void *cookie) +{ + WARN_ON(cookie != cfg_cookie); +} + +static void __init dummy_tlb_flush(unsigned long iova, size_t size, + size_t granule, void *cookie) +{ + WARN_ON(cookie != cfg_cookie); + WARN_ON(!(size & cfg_cookie->pgsize_bitmap)); +} + +static void __init dummy_tlb_add_page(struct iommu_iotlb_gather *gather, + unsigned long iova, size_t granule, + void *cookie) +{ + dummy_tlb_flush(iova, granule, granule, cookie); +} + +static const struct iommu_flush_ops dummy_tlb_ops __initconst = { + .tlb_flush_all = dummy_tlb_flush_all, + .tlb_flush_walk = dummy_tlb_flush, + .tlb_flush_leaf = dummy_tlb_flush, + .tlb_add_page = dummy_tlb_add_page, +}; + +static void __init arm_lpae_dump_ops(struct io_pgtable_ops *ops) +{ + struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops); + struct io_pgtable_cfg *cfg = &data->iop.cfg; + + pr_err("cfg: pgsize_bitmap 0x%lx, ias %u-bit\n", + cfg->pgsize_bitmap, cfg->ias); + pr_err("data: %d levels, 0x%zx pgd_size, %u pg_shift, %u bits_per_level, pgd @ %p\n", + ARM_LPAE_MAX_LEVELS - data->start_level, ARM_LPAE_PGD_SIZE(data), + ilog2(ARM_LPAE_GRANULE(data)), data->bits_per_level, data->pgd); +} + +#define __FAIL(ops, i) ({ \ + WARN(1, "selftest: test failed for fmt idx %d\n", (i)); \ + arm_lpae_dump_ops(ops); \ + selftest_running = false; \ + -EFAULT; \ +}) + +static int __init arm_lpae_run_tests(struct io_pgtable_cfg *cfg) +{ + static const enum io_pgtable_fmt fmts[] __initconst = { + ARM_64_LPAE_S1, + ARM_64_LPAE_S2, + }; + + int i, j; + unsigned long iova; + size_t size; + struct io_pgtable_ops *ops; + + selftest_running = true; + + for (i = 0; i < ARRAY_SIZE(fmts); ++i) { + cfg_cookie = cfg; + ops = alloc_io_pgtable_ops(fmts[i], cfg, cfg); + if (!ops) { + pr_err("selftest: failed to allocate io pgtable ops\n"); + return -ENOMEM; + } + + /* + * Initial sanity checks. + * Empty page tables shouldn't provide any translations. + */ + if (ops->iova_to_phys(ops, 42)) + return __FAIL(ops, i); + + if (ops->iova_to_phys(ops, SZ_1G + 42)) + return __FAIL(ops, i); + + if (ops->iova_to_phys(ops, SZ_2G + 42)) + return __FAIL(ops, i); + + /* + * Distinct mappings of different granule sizes. + */ + iova = 0; + for_each_set_bit(j, &cfg->pgsize_bitmap, BITS_PER_LONG) { + size = 1UL << j; + + if (ops->map(ops, iova, iova, size, IOMMU_READ | + IOMMU_WRITE | + IOMMU_NOEXEC | + IOMMU_CACHE, GFP_KERNEL)) + return __FAIL(ops, i); + + /* Overlapping mappings */ + if (!ops->map(ops, iova, iova + size, size, + IOMMU_READ | IOMMU_NOEXEC, GFP_KERNEL)) + return __FAIL(ops, i); + + if (ops->iova_to_phys(ops, iova + 42) != (iova + 42)) + return __FAIL(ops, i); + + iova += SZ_1G; + } + + /* Partial unmap */ + size = 1UL << __ffs(cfg->pgsize_bitmap); + if (ops->unmap(ops, SZ_1G + size, size, NULL) != size) + return __FAIL(ops, i); + + /* Remap of partial unmap */ + if (ops->map(ops, SZ_1G + size, size, size, IOMMU_READ, GFP_KERNEL)) + return __FAIL(ops, i); + + if (ops->iova_to_phys(ops, SZ_1G + size + 42) != (size + 42)) + return __FAIL(ops, i); + + /* Full unmap */ + iova = 0; + for_each_set_bit(j, &cfg->pgsize_bitmap, BITS_PER_LONG) { + size = 1UL << j; + + if (ops->unmap(ops, iova, size, NULL) != size) + return __FAIL(ops, i); + + if (ops->iova_to_phys(ops, iova + 42)) + return __FAIL(ops, i); + + /* Remap full block */ + if (ops->map(ops, iova, iova, size, IOMMU_WRITE, GFP_KERNEL)) + return __FAIL(ops, i); + + if (ops->iova_to_phys(ops, iova + 42) != (iova + 42)) + return __FAIL(ops, i); + + iova += SZ_1G; + } + + free_io_pgtable_ops(ops); + } + + selftest_running = false; + return 0; +} + +static int __init arm_lpae_do_selftests(void) +{ + static const unsigned long pgsize[] __initconst = { + SZ_4K | SZ_2M | SZ_1G, + SZ_16K | SZ_32M, + SZ_64K | SZ_512M, + }; + + static const unsigned int ias[] __initconst = { + 32, 36, 40, 42, 44, 48, + }; + + int i, j, pass = 0, fail = 0; + struct io_pgtable_cfg cfg = { + .tlb = &dummy_tlb_ops, + .oas = 48, + .coherent_walk = true, + }; + + for (i = 0; i < ARRAY_SIZE(pgsize); ++i) { + for (j = 0; j < ARRAY_SIZE(ias); ++j) { + cfg.pgsize_bitmap = pgsize[i]; + cfg.ias = ias[j]; + pr_info("selftest: pgsize_bitmap 0x%08lx, IAS %u\n", + pgsize[i], ias[j]); + if (arm_lpae_run_tests(&cfg)) + fail++; + else + pass++; + } + } + + pr_info("selftest: completed with %d PASS %d FAIL\n", pass, fail); + return fail ? -EFAULT : 0; +} +subsys_initcall(arm_lpae_do_selftests); +#endif |