[PATCH 2/4] iommu: add ARM LPAE page table allocator
Will Deacon
will.deacon at arm.com
Thu Nov 27 03:51:16 PST 2014
A number of IOMMUs found in ARM SoCs can walk architecture-compatible
page tables.
This patch adds a generic allocator for Stage-1 and Stage-2 v7/v8
long-descriptor page tables. 4k, 16k and 64k pages are supported, with
up to 4-levels of walk to cover a 48-bit address space.
Signed-off-by: Will Deacon <will.deacon at arm.com>
---
MAINTAINERS | 1 +
drivers/iommu/Kconfig | 9 +
drivers/iommu/Makefile | 1 +
drivers/iommu/io-pgtable-arm.c | 735 +++++++++++++++++++++++++++++++++++++++++
drivers/iommu/io-pgtable.c | 7 +
drivers/iommu/io-pgtable.h | 12 +
6 files changed, 765 insertions(+)
create mode 100644 drivers/iommu/io-pgtable-arm.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 0ff630de8a6d..d3ca31b7c960 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1562,6 +1562,7 @@ M: Will Deacon <will.deacon at arm.com>
L: linux-arm-kernel at lists.infradead.org (moderated for non-subscribers)
S: Maintained
F: drivers/iommu/arm-smmu.c
+F: drivers/iommu/io-pgtable-arm.c
ARM64 PORT (AARCH64 ARCHITECTURE)
M: Catalin Marinas <catalin.marinas at arm.com>
diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index 0f10554e7114..e1742a0146f8 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -19,6 +19,15 @@ menu "Generic IOMMU Pagetable Support"
config IOMMU_IO_PGTABLE
bool
+config IOMMU_IO_PGTABLE_LPAE
+ bool "ARMv7/v8 Long Descriptor Format"
+ select IOMMU_IO_PGTABLE
+ help
+ Enable support for the ARM long descriptor pagetable format.
+ This allocator supports 4K/2M/1G, 16K/32M and 64K/512M page
+ sizes at both stage-1 and stage-2, as well as address spaces
+ up to 48-bits in size.
+
endmenu
config OF_IOMMU
diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile
index aff244c78181..269cdd82b672 100644
--- a/drivers/iommu/Makefile
+++ b/drivers/iommu/Makefile
@@ -2,6 +2,7 @@ obj-$(CONFIG_IOMMU_API) += iommu.o
obj-$(CONFIG_IOMMU_API) += iommu-traces.o
obj-$(CONFIG_IOMMU_API) += iommu-sysfs.o
obj-$(CONFIG_IOMMU_IO_PGTABLE) += io-pgtable.o
+obj-$(CONFIG_IOMMU_IO_PGTABLE_LPAE) += io-pgtable-arm.o
obj-$(CONFIG_OF_IOMMU) += of_iommu.o
obj-$(CONFIG_MSM_IOMMU) += msm_iommu.o msm_iommu_dev.o
obj-$(CONFIG_AMD_IOMMU) += amd_iommu.o amd_iommu_init.o
diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c
new file mode 100644
index 000000000000..9dbaa2e48424
--- /dev/null
+++ b/drivers/iommu/io-pgtable-arm.c
@@ -0,0 +1,735 @@
+/*
+ * CPU-agnostic ARM page table allocator.
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Copyright (C) 2014 ARM Limited
+ *
+ * Author: Will Deacon <will.deacon at arm.com>
+ */
+
+#define pr_fmt(fmt) "arm-lpae io-pgtable: " fmt
+
+#include <linux/iommu.h>
+#include <linux/kernel.h>
+#include <linux/sizes.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#include "io-pgtable.h"
+
+#define ARM_LPAE_MAX_ADDR_BITS 48
+#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_pgtable(x) \
+ container_of((x), struct io_pgtable, ops)
+
+#define io_pgtable_ops_to_data(x) \
+ io_pgtable_to_data(io_pgtable_ops_to_pgtable(x))
+
+/*
+ * For consistency with the architecture, we always consider
+ * ARM_LPAE_MAX_LEVELS levels, with the walk starting at level n >=0
+ */
+#define ARM_LPAE_START_LVL(d) (ARM_LPAE_MAX_LEVELS - (d)->levels)
+
+/*
+ * 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) \
+ ((((d)->levels - ((l) - ARM_LPAE_START_LVL(d) + 1)) \
+ * (d)->bits_per_level) + (d)->pg_shift)
+
+/*
+ * 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) == ARM_LPAE_START_LVL(d) ? ilog2((d)->pages_per_pgd) : 0)
+
+#define ARM_LPAE_LVL_IDX(a,l,d) \
+ (((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) \
+ (1 << (ilog2(sizeof(arm_lpae_iopte)) + \
+ ((ARM_LPAE_MAX_LEVELS - (l)) * (d)->bits_per_level)))
+
+/* 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_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_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)
+
+/* 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_TCR_EAE (1 << 31)
+
+#define ARM_LPAE_TCR_TG0_4K (0 << 14)
+#define ARM_LPAE_TCR_TG0_64K (1 << 14)
+#define ARM_LPAE_TCR_TG0_16K (2 << 14)
+
+#define ARM_LPAE_TCR_SH0_SHIFT 12
+#define ARM_LPAE_TCR_SH0_MASK 0x3
+#define ARM_LPAE_TCR_SH_NS 0
+#define ARM_LPAE_TCR_SH_OS 2
+#define ARM_LPAE_TCR_SH_IS 3
+
+#define ARM_LPAE_TCR_ORGN0_SHIFT 10
+#define ARM_LPAE_TCR_IRGN0_SHIFT 8
+#define ARM_LPAE_TCR_RGN_MASK 0x3
+#define ARM_LPAE_TCR_RGN_NC 0
+#define ARM_LPAE_TCR_RGN_WBWA 1
+#define ARM_LPAE_TCR_RGN_WT 2
+#define ARM_LPAE_TCR_RGN_WB 3
+
+#define ARM_LPAE_TCR_SL0_SHIFT 6
+#define ARM_LPAE_TCR_SL0_MASK 0x3
+
+#define ARM_LPAE_TCR_T0SZ_SHIFT 0
+#define ARM_LPAE_TCR_SZ_MASK 0xf
+
+#define ARM_LPAE_TCR_PS_SHIFT 16
+#define ARM_LPAE_TCR_PS_MASK 0x7
+
+#define ARM_LPAE_TCR_IPS_SHIFT 32
+#define ARM_LPAE_TCR_IPS_MASK 0x7
+
+#define ARM_LPAE_TCR_PS_32_BIT 0x0ULL
+#define ARM_LPAE_TCR_PS_36_BIT 0x1ULL
+#define ARM_LPAE_TCR_PS_40_BIT 0x2ULL
+#define ARM_LPAE_TCR_PS_42_BIT 0x3ULL
+#define ARM_LPAE_TCR_PS_44_BIT 0x4ULL
+#define ARM_LPAE_TCR_PS_48_BIT 0x5ULL
+
+#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_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
+
+/* IOPTE accessors */
+#define iopte_deref(pte,d) \
+ (__va((pte) & ((1ULL << ARM_LPAE_MAX_ADDR_BITS) - 1) \
+ & ~((1ULL << (d)->pg_shift) - 1)))
+
+#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)
+
+#define iopte_leaf(pte,l) \
+ (l == (ARM_LPAE_MAX_LEVELS - 1) ? \
+ (iopte_type(pte,l) == ARM_LPAE_PTE_TYPE_PAGE) : \
+ (iopte_type(pte,l) == ARM_LPAE_PTE_TYPE_BLOCK))
+
+#define iopte_to_pfn(pte,d) \
+ (((pte) & ((1ULL << ARM_LPAE_MAX_ADDR_BITS) - 1)) >> (d)->pg_shift)
+
+#define pfn_to_iopte(pfn,d) \
+ (((pfn) << (d)->pg_shift) & ((1ULL << ARM_LPAE_MAX_ADDR_BITS) - 1))
+
+struct arm_lpae_io_pgtable {
+ struct io_pgtable iop;
+
+ int levels;
+ int pages_per_pgd;
+ unsigned long pg_shift;
+ unsigned long bits_per_level;
+
+ void *pgd;
+};
+
+typedef u64 arm_lpae_iopte;
+
+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 = prot;
+
+ /* We require an unmap first */
+ if (iopte_leaf(*ptep, lvl))
+ return -EEXIST;
+
+ if (lvl == ARM_LPAE_MAX_LEVELS - 1)
+ pte |= ARM_LPAE_PTE_TYPE_PAGE;
+ else
+ pte |= ARM_LPAE_PTE_TYPE_BLOCK;
+
+ pte |= ARM_LPAE_PTE_AF | ARM_LPAE_PTE_SH_IS;
+ pte |= pfn_to_iopte(paddr >> data->pg_shift, data);
+
+ *ptep = pte;
+ data->iop.cfg.tlb->flush_pgtable(ptep, sizeof(*ptep), data->iop.cookie);
+ return 0;
+}
+
+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)
+{
+ arm_lpae_iopte *cptep, pte;
+ void *cookie = data->iop.cookie;
+ size_t block_size = ARM_LPAE_BLOCK_SIZE(lvl, data);
+
+ /* 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 && (size & data->iop.cfg.pgsize_bitmap))
+ 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 = *ptep;
+ if (!pte) {
+ cptep = alloc_pages_exact(1UL << data->pg_shift,
+ GFP_ATOMIC | __GFP_ZERO);
+ if (!cptep)
+ return -ENOMEM;
+
+ data->iop.cfg.tlb->flush_pgtable(cptep, 1UL << data->pg_shift,
+ cookie);
+ pte = __pa(cptep) | ARM_LPAE_PTE_TYPE_TABLE;
+ *ptep = pte;
+ data->iop.cfg.tlb->flush_pgtable(ptep, sizeof(*ptep), cookie);
+ } else {
+ cptep = iopte_deref(pte, data);
+ }
+
+ /* Rinse, repeat */
+ return __arm_lpae_map(data, iova, paddr, size, prot, lvl + 1, cptep);
+}
+
+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_LPAE_S1) {
+ pte = ARM_LPAE_PTE_AP_UNPRIV | ARM_LPAE_PTE_nG;
+
+ if (!(prot & IOMMU_WRITE) && (prot & IOMMU_READ))
+ pte |= ARM_LPAE_PTE_AP_RDONLY;
+
+ if (prot & IOMMU_CACHE)
+ pte |= (ARM_LPAE_MAIR_ATTR_IDX_CACHE
+ << ARM_LPAE_PTE_ATTRINDX_SHIFT);
+ } 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;
+ if (prot & IOMMU_CACHE)
+ pte |= ARM_LPAE_PTE_MEMATTR_OIWB;
+ else
+ pte |= ARM_LPAE_PTE_MEMATTR_NC;
+ }
+
+ if (prot & IOMMU_NOEXEC)
+ pte |= ARM_LPAE_PTE_XN;
+
+ 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)
+{
+ struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
+ arm_lpae_iopte *ptep = data->pgd;
+ int lvl = ARM_LPAE_START_LVL(data);
+ arm_lpae_iopte prot;
+
+ /* If no access, then nothing to do */
+ if (!(iommu_prot & (IOMMU_READ | IOMMU_WRITE)))
+ return 0;
+
+ prot = arm_lpae_prot_to_pte(data, iommu_prot);
+ return __arm_lpae_map(data, iova, paddr, size, prot, lvl, ptep);
+}
+
+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;
+
+ /* Only leaf entries at the last level */
+ if (lvl == ARM_LPAE_MAX_LEVELS - 1)
+ return;
+
+ table_size = 1UL << data->pg_shift;
+ if (lvl == ARM_LPAE_START_LVL(data))
+ table_size *= data->pages_per_pgd;
+
+ start = ptep;
+ end = (void *)ptep + table_size;
+
+ while (ptep != end) {
+ arm_lpae_iopte pte = *ptep++;
+
+ if (!pte || iopte_leaf(pte, lvl))
+ continue;
+
+ __arm_lpae_free_pgtable(data, lvl + 1, iopte_deref(pte, data));
+ }
+
+ free_pages_exact(start, table_size);
+}
+
+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, ARM_LPAE_START_LVL(data), data->pgd);
+ kfree(data);
+}
+
+static int arm_lpae_split_blk_unmap(struct arm_lpae_io_pgtable *data,
+ unsigned long iova, size_t size,
+ arm_lpae_iopte prot, int lvl,
+ arm_lpae_iopte *ptep, size_t blk_size)
+{
+ unsigned long blk_start, blk_end;
+ phys_addr_t blk_paddr;
+ arm_lpae_iopte table = 0;
+ void *cookie = data->iop.cookie;
+ struct iommu_gather_ops *tlb = data->iop.cfg.tlb;
+
+ blk_start = iova & ~(blk_size - 1);
+ blk_end = blk_start + blk_size;
+ blk_paddr = iopte_to_pfn(*ptep, data) << data->pg_shift;
+
+ for (; blk_start < blk_end; blk_start += size, blk_paddr += size) {
+ arm_lpae_iopte *tablep;
+
+ /* Unmap! */
+ if (blk_start == iova)
+ continue;
+
+ /* __arm_lpae_map expects a pointer to the start of the table */
+ tablep = &table - ARM_LPAE_LVL_IDX(blk_start, lvl, data);
+ if (__arm_lpae_map(data, blk_start, blk_paddr, size, prot, lvl,
+ tablep) < 0) {
+ if (table) {
+ /* Free the table we allocated */
+ tablep = iopte_deref(table, data);
+ __arm_lpae_free_pgtable(data, lvl + 1, tablep);
+ }
+ return 0; /* Bytes unmapped */
+ }
+ }
+
+ *ptep = table;
+ tlb->flush_pgtable(ptep, sizeof(*ptep), cookie);
+ iova &= ~(blk_size - 1);
+ tlb->tlb_add_flush(iova, blk_size, true, cookie);
+ return size;
+}
+
+static int __arm_lpae_unmap(struct arm_lpae_io_pgtable *data,
+ unsigned long iova, size_t size, int lvl,
+ arm_lpae_iopte *ptep)
+{
+ arm_lpae_iopte pte;
+ struct iommu_gather_ops *tlb = data->iop.cfg.tlb;
+ void *cookie = data->iop.cookie;
+ size_t blk_size = ARM_LPAE_BLOCK_SIZE(lvl, data);
+
+ ptep += ARM_LPAE_LVL_IDX(iova, lvl, data);
+ pte = *ptep;
+
+ /* Something went horribly wrong and we ran out of page table */
+ if (WARN_ON(!pte || (lvl == ARM_LPAE_MAX_LEVELS)))
+ return 0;
+
+ /* If the size matches this level, we're in the right place */
+ if (size == blk_size) {
+ *ptep = 0;
+ tlb->flush_pgtable(ptep, sizeof(*ptep), cookie);
+
+ if (!iopte_leaf(pte, lvl)) {
+ /* Also flush any partial walks */
+ tlb->tlb_add_flush(iova, size, false, cookie);
+ tlb->tlb_sync(data->iop.cookie);
+ ptep = iopte_deref(pte, data);
+ __arm_lpae_free_pgtable(data, lvl + 1, ptep);
+ } else {
+ tlb->tlb_add_flush(iova, size, true, cookie);
+ }
+
+ return size;
+ } else if (iopte_leaf(pte, lvl)) {
+ /*
+ * 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, iova, size,
+ iopte_prot(pte), lvl, ptep,
+ blk_size);
+ }
+
+ /* Keep on walkin' */
+ ptep = iopte_deref(pte, data);
+ return __arm_lpae_unmap(data, iova, size, lvl + 1, ptep);
+}
+
+static int arm_lpae_unmap(struct io_pgtable_ops *ops, unsigned long iova,
+ size_t size)
+{
+ size_t unmapped;
+ struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
+ struct io_pgtable *iop = &data->iop;
+ arm_lpae_iopte *ptep = data->pgd;
+ int lvl = ARM_LPAE_START_LVL(data);
+
+ unmapped = __arm_lpae_unmap(data, iova, size, lvl, ptep);
+ if (unmapped)
+ iop->cfg.tlb->tlb_sync(iop->cookie);
+
+ return unmapped;
+}
+
+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 = ARM_LPAE_START_LVL(data);
+
+ do {
+ /* Valid IOPTE pointer? */
+ if (!ptep)
+ return 0;
+
+ /* Grab the IOPTE we're interested in */
+ pte = *(ptep + ARM_LPAE_LVL_IDX(iova, lvl, data));
+
+ /* Valid entry? */
+ if (!pte)
+ return 0;
+
+ /* Leaf entry? */
+ if (iopte_leaf(pte,lvl))
+ 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 &= ((1 << data->pg_shift) - 1);
+ return ((phys_addr_t)iopte_to_pfn(pte,data) << data->pg_shift) | iova;
+}
+
+static void arm_lpae_restrict_pgsizes(struct io_pgtable_cfg *cfg)
+{
+ unsigned long granule;
+
+ /*
+ * 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:
+ cfg->pgsize_bitmap &= (SZ_4K | SZ_2M | SZ_1G);
+ break;
+ case SZ_16K:
+ cfg->pgsize_bitmap &= (SZ_16K | SZ_32M);
+ break;
+ case SZ_64K:
+ cfg->pgsize_bitmap &= (SZ_64K | SZ_512M);
+ break;
+ default:
+ cfg->pgsize_bitmap = 0;
+ }
+}
+
+static struct arm_lpae_io_pgtable *
+arm_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg)
+{
+ unsigned long va_bits;
+ struct arm_lpae_io_pgtable *data;
+
+ 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;
+
+ data->pages_per_pgd = 1;
+ data->pg_shift = __ffs(cfg->pgsize_bitmap);
+ data->bits_per_level = data->pg_shift - ilog2(sizeof(arm_lpae_iopte));
+
+ va_bits = cfg->ias - data->pg_shift;
+ data->levels = DIV_ROUND_UP(va_bits, data->bits_per_level);
+
+ 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_lpae_alloc_pgtable_s1(struct io_pgtable_cfg *cfg,
+ void *cookie)
+{
+ u64 reg;
+ struct arm_lpae_io_pgtable *data = arm_lpae_alloc_pgtable(cfg);
+
+ if (!data)
+ return NULL;
+
+ /* TCR */
+ reg = ARM_LPAE_TCR_EAE |
+ (ARM_LPAE_TCR_SH_IS << ARM_LPAE_TCR_SH0_SHIFT) |
+ (ARM_LPAE_TCR_RGN_WBWA << ARM_LPAE_TCR_IRGN0_SHIFT) |
+ (ARM_LPAE_TCR_RGN_WBWA << ARM_LPAE_TCR_ORGN0_SHIFT);
+
+ switch (1 << data->pg_shift) {
+ case SZ_4K:
+ reg |= ARM_LPAE_TCR_TG0_4K;
+ break;
+ case SZ_16K:
+ reg |= ARM_LPAE_TCR_TG0_16K;
+ break;
+ case SZ_64K:
+ reg |= ARM_LPAE_TCR_TG0_64K;
+ break;
+ }
+
+ switch (cfg->oas) {
+ case 32:
+ reg |= (ARM_LPAE_TCR_PS_32_BIT << ARM_LPAE_TCR_IPS_SHIFT);
+ break;
+ case 36:
+ reg |= (ARM_LPAE_TCR_PS_36_BIT << ARM_LPAE_TCR_IPS_SHIFT);
+ break;
+ case 40:
+ reg |= (ARM_LPAE_TCR_PS_40_BIT << ARM_LPAE_TCR_IPS_SHIFT);
+ break;
+ case 42:
+ reg |= (ARM_LPAE_TCR_PS_42_BIT << ARM_LPAE_TCR_IPS_SHIFT);
+ break;
+ case 44:
+ reg |= (ARM_LPAE_TCR_PS_44_BIT << ARM_LPAE_TCR_IPS_SHIFT);
+ break;
+ case 48:
+ reg |= (ARM_LPAE_TCR_PS_48_BIT << ARM_LPAE_TCR_IPS_SHIFT);
+ break;
+ default:
+ goto out_free_data;
+ }
+
+ reg |= (64ULL - cfg->ias) << ARM_LPAE_TCR_T0SZ_SHIFT;
+ cfg->arm_lpae_s1_cfg.tcr = reg;
+
+ /* 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));
+
+ cfg->arm_lpae_s1_cfg.mair[0] = reg;
+ cfg->arm_lpae_s1_cfg.mair[1] = 0;
+
+ /* Looking good; allocate a pgd */
+ data->pgd = alloc_pages_exact(1UL << data->pg_shift,
+ GFP_KERNEL | __GFP_ZERO);
+ if (!data->pgd)
+ goto out_free_data;
+
+ cfg->tlb->flush_pgtable(data->pgd, (1UL << data->pg_shift), cookie);
+
+ /* TTBRs */
+ cfg->arm_lpae_s1_cfg.ttbr[0] = virt_to_phys(data->pgd);
+ cfg->arm_lpae_s1_cfg.ttbr[1] = 0;
+ return &data->iop;
+
+out_free_data:
+ kfree(data);
+ return NULL;
+}
+
+static struct io_pgtable *arm_lpae_alloc_pgtable_s2(struct io_pgtable_cfg *cfg,
+ void *cookie)
+{
+ u64 reg, sl;
+ size_t pgd_size;
+ struct arm_lpae_io_pgtable *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->levels == ARM_LPAE_MAX_LEVELS) {
+ unsigned long pgd_bits, pgd_pages;
+ unsigned long va_bits = cfg->ias - data->pg_shift;
+
+ pgd_bits = data->bits_per_level * (data->levels - 1);
+ pgd_pages = 1 << (va_bits - pgd_bits);
+ if (pgd_pages <= ARM_LPAE_S2_MAX_CONCAT_PAGES) {
+ data->pages_per_pgd = pgd_pages;
+ data->levels--;
+ }
+ }
+
+ /* VTCR */
+ reg = ARM_LPAE_TCR_EAE |
+ (ARM_LPAE_TCR_SH_IS << ARM_LPAE_TCR_SH0_SHIFT) |
+ (ARM_LPAE_TCR_RGN_WBWA << ARM_LPAE_TCR_IRGN0_SHIFT) |
+ (ARM_LPAE_TCR_RGN_WBWA << ARM_LPAE_TCR_ORGN0_SHIFT);
+
+ sl = ARM_LPAE_START_LVL(data);
+
+ switch (1 << data->pg_shift) {
+ case SZ_4K:
+ reg |= ARM_LPAE_TCR_TG0_4K;
+ sl++; /* SL0 format is different for 4K granule size */
+ break;
+ case SZ_16K:
+ reg |= ARM_LPAE_TCR_TG0_16K;
+ break;
+ case SZ_64K:
+ reg |= ARM_LPAE_TCR_TG0_64K;
+ break;
+ }
+
+ switch (cfg->oas) {
+ case 32:
+ reg |= (ARM_LPAE_TCR_PS_32_BIT << ARM_LPAE_TCR_PS_SHIFT);
+ break;
+ case 36:
+ reg |= (ARM_LPAE_TCR_PS_36_BIT << ARM_LPAE_TCR_PS_SHIFT);
+ break;
+ case 40:
+ reg |= (ARM_LPAE_TCR_PS_40_BIT << ARM_LPAE_TCR_PS_SHIFT);
+ break;
+ case 42:
+ reg |= (ARM_LPAE_TCR_PS_42_BIT << ARM_LPAE_TCR_PS_SHIFT);
+ break;
+ case 44:
+ reg |= (ARM_LPAE_TCR_PS_44_BIT << ARM_LPAE_TCR_PS_SHIFT);
+ break;
+ case 48:
+ reg |= (ARM_LPAE_TCR_PS_48_BIT << ARM_LPAE_TCR_PS_SHIFT);
+ break;
+ default:
+ goto out_free_data;
+ }
+
+ reg |= (64ULL - cfg->ias) << ARM_LPAE_TCR_T0SZ_SHIFT;
+ reg |= (~sl & ARM_LPAE_TCR_SL0_MASK) << ARM_LPAE_TCR_SL0_SHIFT;
+ cfg->arm_lpae_s2_cfg.vtcr = reg;
+
+ /* Allocate pgd pages */
+ pgd_size = data->pages_per_pgd * (1UL << data->pg_shift);
+ data->pgd = alloc_pages_exact(pgd_size, GFP_KERNEL | __GFP_ZERO);
+ if (!data->pgd)
+ goto out_free_data;
+
+ cfg->tlb->flush_pgtable(data->pgd, pgd_size, cookie);
+
+ /* VTTBR */
+ cfg->arm_lpae_s2_cfg.vttbr = virt_to_phys(data->pgd);
+ return &data->iop;
+
+out_free_data:
+ kfree(data);
+ return NULL;
+}
+
+struct io_pgtable_init_fns io_pgtable_arm_lpae_s1_init_fns = {
+ .alloc = arm_lpae_alloc_pgtable_s1,
+ .free = arm_lpae_free_pgtable,
+};
+
+struct io_pgtable_init_fns io_pgtable_arm_lpae_s2_init_fns = {
+ .alloc = arm_lpae_alloc_pgtable_s2,
+ .free = arm_lpae_free_pgtable,
+};
diff --git a/drivers/iommu/io-pgtable.c b/drivers/iommu/io-pgtable.c
index 82e39a0db94b..d0a2016efcb4 100644
--- a/drivers/iommu/io-pgtable.c
+++ b/drivers/iommu/io-pgtable.c
@@ -25,8 +25,15 @@
#include "io-pgtable.h"
+extern struct io_pgtable_init_fns io_pgtable_arm_lpae_s1_init_fns;
+extern struct io_pgtable_init_fns io_pgtable_arm_lpae_s2_init_fns;
+
static struct io_pgtable_init_fns *io_pgtable_init_table[IO_PGTABLE_NUM_FMTS] =
{
+#ifdef CONFIG_IOMMU_IO_PGTABLE_LPAE
+ [ARM_LPAE_S1] = &io_pgtable_arm_lpae_s1_init_fns,
+ [ARM_LPAE_S2] = &io_pgtable_arm_lpae_s2_init_fns,
+#endif
};
struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,
diff --git a/drivers/iommu/io-pgtable.h b/drivers/iommu/io-pgtable.h
index 5ae75d9cae50..c1cff3d045db 100644
--- a/drivers/iommu/io-pgtable.h
+++ b/drivers/iommu/io-pgtable.h
@@ -33,10 +33,22 @@ struct io_pgtable_cfg {
/* Low-level data specific to the table format */
union {
+ struct {
+ u64 ttbr[2];
+ u64 tcr;
+ u64 mair[2];
+ } arm_lpae_s1_cfg;
+
+ struct {
+ u64 vttbr;
+ u64 vtcr;
+ } arm_lpae_s2_cfg;
};
};
enum io_pgtable_fmt {
+ ARM_LPAE_S1,
+ ARM_LPAE_S2,
IO_PGTABLE_NUM_FMTS,
};
--
2.1.1
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