[PATCH 5/5] iommu/io-pgtable: Add ARMv7 short descriptor support
Robin Murphy
robin.murphy at arm.com
Fri Dec 4 09:53:02 PST 2015
Add a nearly-complete ARMv7 short descriptor implementation, omitting
only a few legacy and CPU-centric aspects which shouldn't be necessary
for IOMMU API use anyway.
Signed-off-by: Yong Wu <yong.wu at mediatek.com>
Signed-off-by: Robin Murphy <robin.murphy at arm.com>
---
drivers/iommu/Kconfig | 19 +
drivers/iommu/Makefile | 1 +
drivers/iommu/io-pgtable-arm-v7s.c | 836 +++++++++++++++++++++++++++++++++++++
drivers/iommu/io-pgtable.c | 3 +
drivers/iommu/io-pgtable.h | 14 +-
5 files changed, 872 insertions(+), 1 deletion(-)
create mode 100644 drivers/iommu/io-pgtable-arm-v7s.c
diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index b9094e9..b591022 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -39,6 +39,25 @@ config IOMMU_IO_PGTABLE_LPAE_SELFTEST
If unsure, say N here.
+config IOMMU_IO_PGTABLE_ARMV7S
+ bool "ARMv7/v8 Short Descriptor Format"
+ select IOMMU_IO_PGTABLE
+ depends on HAS_DMA && (ARM || ARM64 || COMPILE_TEST)
+ help
+ Enable support for the ARM Short-descriptor pagetable format.
+ This supports 32-bit virtual and physical addresses mapped using
+ 2-level tables with 4KB pages/1MB sections, and contiguous entries
+ for 64KB pages/16MB supersections if indicated by the IOMMU driver.
+
+config IOMMU_IO_PGTABLE_ARMV7S_SELFTEST
+ bool "ARMv7s selftests"
+ depends on IOMMU_IO_PGTABLE_ARMV7S
+ help
+ Enable self-tests for ARMv7s page table allocator. This performs
+ a series of page-table consistency checks during boot.
+
+ If unsure, say N here.
+
endmenu
config IOMMU_IOVA
diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile
index 68faca02..47f11d9 100644
--- a/drivers/iommu/Makefile
+++ b/drivers/iommu/Makefile
@@ -3,6 +3,7 @@ obj-$(CONFIG_IOMMU_API) += iommu-traces.o
obj-$(CONFIG_IOMMU_API) += iommu-sysfs.o
obj-$(CONFIG_IOMMU_DMA) += dma-iommu.o
obj-$(CONFIG_IOMMU_IO_PGTABLE) += io-pgtable.o
+obj-$(CONFIG_IOMMU_IO_PGTABLE_ARMV7S) += io-pgtable-arm-v7s.o
obj-$(CONFIG_IOMMU_IO_PGTABLE_LPAE) += io-pgtable-arm.o
obj-$(CONFIG_IOMMU_IOVA) += iova.o
obj-$(CONFIG_OF_IOMMU) += of_iommu.o
diff --git a/drivers/iommu/io-pgtable-arm-v7s.c b/drivers/iommu/io-pgtable-arm-v7s.c
new file mode 100644
index 0000000..52e85a0
--- /dev/null
+++ b/drivers/iommu/io-pgtable-arm-v7s.c
@@ -0,0 +1,836 @@
+/*
+ * CPU-agnostic ARM page table allocator.
+ *
+ * ARMv7 Short-descriptor format, supporting
+ * - Basic memory attributes
+ * - Simplified access permissions (AP[2:1] model)
+ * - Backwards-compatible TEX remap
+ * - Large pages/supersections (if indicated by the caller)
+ *
+ * Not supporting:
+ * - Legacy access permissions (AP[2:0] model)
+ *
+ * Almost certainly never supporting:
+ * - PXN
+ * - Domains
+ *
+ * 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) 2014-2015 ARM Limited
+ * Copyright (c) 2014-2015 MediaTek Inc.
+ */
+
+#define pr_fmt(fmt) "arm-v7s io-pgtable: " fmt
+
+#include <linux/iommu.h>
+#include <linux/kernel.h>
+#include <linux/sizes.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#include <asm/barrier.h>
+
+#include "io-pgtable.h"
+
+/* Struct accessors */
+#define io_pgtable_to_data(x) \
+ container_of((x), struct arm_v7s_io_pgtable, iop)
+
+#define io_pgtable_ops_to_data(x) \
+ io_pgtable_to_data(io_pgtable_ops_to_pgtable(x))
+
+/*
+ * We have 32 bits total; 12 bits resolved at level 1, 8 bits at level 2,
+ * and 12 bits in a page. With some carefully-chosen coefficients we can
+ * hide the ugly inconsistencies behind these macros and at least let the
+ * rest of the code pretend to be somewhat sane.
+ */
+#define ARM_V7S_ADDR_BITS 32
+#define _ARM_V7S_LVL_BITS(lvl) (16 - (lvl) * 4)
+#define ARM_V7S_LVL_SHIFT(lvl) (ARM_V7S_ADDR_BITS - (4 + 8 * (lvl)))
+#define ARM_V7S_TABLE_SHIFT 10
+
+#define ARM_V7S_PTES_PER_LVL(lvl) (1 << _ARM_V7S_LVL_BITS(lvl))
+#define ARM_V7S_TABLE_SIZE(lvl) \
+ (ARM_V7S_PTES_PER_LVL(lvl) * sizeof(arm_v7s_iopte))
+
+#define ARM_V7S_BLOCK_SIZE(lvl) (1UL << ARM_V7S_LVL_SHIFT(lvl))
+#define ARM_V7S_LVL_MASK(lvl) ((u32)(~0U << ARM_V7S_LVL_SHIFT(lvl)))
+#define ARM_V7S_TABLE_MASK ((u32)(~0U << ARM_V7S_TABLE_SHIFT))
+#define _ARM_V7S_IDX_MASK(lvl) (ARM_V7S_PTES_PER_LVL(lvl) - 1)
+#define ARM_V7S_LVL_IDX(addr, lvl) ({ \
+ int _l = lvl; \
+ ((u32)(addr) >> ARM_V7S_LVL_SHIFT(_l)) & _ARM_V7S_IDX_MASK(_l); \
+})
+
+#define ARM_V7S_CONT_PAGES 16
+
+/* PTE type bits: these are all mixed up with XN/PXN bits in most cases */
+#define ARM_V7S_PTE_TYPE_TABLE 0x1
+#define ARM_V7S_PTE_TYPE_PAGE 0x2
+#define ARM_V7S_PTE_TYPE_CONT_PAGE 0x1
+
+#define ARM_V7S_PTE_IS_VALID(pte) (((pte) & 0x3) != 0)
+#define ARM_V7S_PTE_IS_TABLE(pte, lvl) (lvl < 2 && ((pte) & ARM_V7S_PTE_TYPE_TABLE))
+
+/* Page table bits */
+#define ARM_V7S_ATTR_XN(lvl) BIT(4 * (2 - (lvl)))
+#define ARM_V7S_ATTR_B BIT(2)
+#define ARM_V7S_ATTR_C BIT(3)
+#define ARM_V7S_ATTR_NS_TABLE BIT(3)
+#define ARM_V7S_ATTR_NS_SECTION BIT(19)
+
+#define ARM_V7S_CONT_SECTION BIT(18)
+#define ARM_V7S_CONT_PAGE_XN_SHIFT 15
+
+/*
+ * The attribute bits are consistently ordered*, but occupy bits [17:10] of
+ * a level 1 PTE vs. bits [11:4] at level 2. Thus we define the individual
+ * fields relative to that 8-bit block, plus a total shift relative to the PTE.
+ */
+#define ARM_V7S_ATTR_SHIFT(lvl) (16 - (lvl) * 6)
+
+#define ARM_V7S_ATTR_MASK 0xff
+#define ARM_V7S_ATTR_AP0 BIT(0)
+#define ARM_V7S_ATTR_AP1 BIT(1)
+#define ARM_V7S_ATTR_AP2 BIT(5)
+#define ARM_V7S_ATTR_S BIT(6)
+#define ARM_V7S_ATTR_NG BIT(7)
+#define ARM_V7S_TEX_SHIFT 2
+#define ARM_V7S_TEX_MASK 0x7
+#define ARM_V7S_ATTR_TEX(val) (((val) & ARM_V7S_TEX_MASK) << ARM_V7S_TEX_SHIFT)
+
+/* *well, except for TEX on level 2 large pages, of course :( */
+#define ARM_V7S_CONT_PAGE_TEX_SHIFT 6
+#define ARM_V7S_CONT_PAGE_TEX_MASK (ARM_V7S_TEX_MASK << ARM_V7S_CONT_PAGE_TEX_SHIFT)
+
+/* Simplified access permissions */
+#define ARM_V7S_PTE_AF ARM_V7S_ATTR_AP0
+#define ARM_V7S_PTE_AP_UNPRIV ARM_V7S_ATTR_AP1
+#define ARM_V7S_PTE_AP_RDONLY ARM_V7S_ATTR_AP2
+
+/* Register bits */
+#define ARM_V7S_RGN_NC 0
+#define ARM_V7S_RGN_WBWA 1
+#define ARM_V7S_RGN_WT 2
+#define ARM_V7S_RGN_WB 3
+
+#define ARM_V7S_PRRR_TYPE_DEVICE 1
+#define ARM_V7S_PRRR_TYPE_NORMAL 2
+#define ARM_V7S_PRRR_TR(n, type) (((type) & 0x3) << ((n) * 2))
+#define ARM_V7S_PRRR_DS0 BIT(16)
+#define ARM_V7S_PRRR_DS1 BIT(17)
+#define ARM_V7S_PRRR_NS0 BIT(18)
+#define ARM_V7S_PRRR_NS1 BIT(19)
+#define ARM_V7S_PRRR_NOS(n) BIT((n) + 24)
+
+#define ARM_V7S_NMRR_IR(n, attr) (((attr) & 0x3) << ((n) * 2))
+#define ARM_V7S_NMRR_OR(n, attr) (((attr) & 0x3) << ((n) * 2 + 16))
+
+#define ARM_V7S_TTBR_S BIT(1)
+#define ARM_V7S_TTBR_NOS BIT(5)
+#define ARM_V7S_TTBR_ORGN_ATTR(attr) (((attr) & 0x3) << 3)
+#define ARM_V7S_TTBR_IRGN_ATTR(attr) \
+ ((((attr) & 0x1) << 6) | (((attr) & 0x2) >> 1))
+
+#define ARM_V7S_TCR_PD1 BIT(5)
+
+typedef u32 arm_v7s_iopte;
+
+static bool selftest_running;
+
+struct arm_v7s_io_pgtable {
+ struct io_pgtable iop;
+
+ arm_v7s_iopte *pgd;
+ struct kmem_cache *l2_tables;
+};
+
+static dma_addr_t __arm_v7s_dma_addr(void *pages)
+{
+ return (dma_addr_t)virt_to_phys(pages);
+}
+
+static arm_v7s_iopte *iopte_deref(arm_v7s_iopte pte, int lvl)
+{
+ if (ARM_V7S_PTE_IS_TABLE(pte, lvl))
+ pte &= ARM_V7S_TABLE_MASK;
+ else
+ pte &= ARM_V7S_LVL_MASK(lvl);
+ return phys_to_virt(pte);
+}
+
+static void *__arm_v7s_alloc_table(int lvl, gfp_t gfp,
+ struct arm_v7s_io_pgtable *data)
+{
+ struct device *dev = data->iop.cfg.iommu_dev;
+ dma_addr_t dma;
+ size_t size = ARM_V7S_TABLE_SIZE(lvl);
+ void *table = NULL;
+
+ if (lvl == 1)
+ table = (void *)__get_dma_pages(__GFP_ZERO, get_order(size));
+ else if (lvl == 2)
+ table = kmem_cache_zalloc(data->l2_tables, gfp);
+ if (table && !selftest_running) {
+ dma = dma_map_single(dev, table, 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(table))
+ goto out_unmap;
+ }
+ return table;
+
+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:
+ if (lvl == 1)
+ free_pages((unsigned long)table, get_order(size));
+ else
+ kmem_cache_free(data->l2_tables, table);
+ return NULL;
+}
+
+static void __arm_v7s_free_table(void *table, int lvl,
+ struct arm_v7s_io_pgtable *data)
+{
+ struct device *dev = data->iop.cfg.iommu_dev;
+ size_t size = ARM_V7S_TABLE_SIZE(lvl);
+
+ if (!selftest_running)
+ dma_unmap_single(dev, __arm_v7s_dma_addr(table), size,
+ DMA_TO_DEVICE);
+ if (lvl == 1)
+ free_pages((unsigned long)table, get_order(size));
+ else
+ kmem_cache_free(data->l2_tables, table);
+}
+
+static void __arm_v7s_pte_sync(arm_v7s_iopte *ptep, int num_entries,
+ struct io_pgtable_cfg *cfg)
+{
+ if (selftest_running)
+ return;
+
+ dma_sync_single_for_device(cfg->iommu_dev, __arm_v7s_dma_addr(ptep),
+ num_entries * sizeof(*ptep), DMA_TO_DEVICE);
+}
+static void __arm_v7s_set_pte(arm_v7s_iopte *ptep, arm_v7s_iopte pte,
+ int num_entries, struct io_pgtable_cfg *cfg)
+{
+ int i;
+
+ for (i = 0; i < num_entries; i++)
+ ptep[i] = pte;
+
+ __arm_v7s_pte_sync(ptep, num_entries, cfg);
+}
+
+static arm_v7s_iopte arm_v7s_prot_to_pte(int prot, int lvl,
+ struct io_pgtable_cfg *cfg)
+{
+ bool ap = !(cfg->quirks & IO_PGTABLE_QUIRK_NO_PERMS);
+ arm_v7s_iopte pte = ARM_V7S_ATTR_NG | ARM_V7S_ATTR_S |
+ ARM_V7S_ATTR_TEX(1);
+
+ if (ap) {
+ pte |= ARM_V7S_PTE_AF | ARM_V7S_PTE_AP_UNPRIV;
+ if (!(prot & IOMMU_WRITE))
+ pte |= ARM_V7S_PTE_AP_RDONLY;
+ }
+ pte <<= ARM_V7S_ATTR_SHIFT(lvl);
+
+ if ((prot & IOMMU_NOEXEC) && ap)
+ pte |= ARM_V7S_ATTR_XN(lvl);
+ if (prot & IOMMU_CACHE)
+ pte |= ARM_V7S_ATTR_B | ARM_V7S_ATTR_C;
+
+ return pte;
+}
+
+static int arm_v7s_pte_to_prot(arm_v7s_iopte pte, int lvl)
+{
+ int prot = IOMMU_READ;
+
+ if (pte & (ARM_V7S_PTE_AP_RDONLY << ARM_V7S_ATTR_SHIFT(lvl)))
+ prot |= IOMMU_WRITE;
+ if (pte & ARM_V7S_ATTR_C)
+ prot |= IOMMU_CACHE;
+
+ return prot;
+}
+
+static arm_v7s_iopte arm_v7s_pte_to_cont(arm_v7s_iopte pte, int lvl)
+{
+ if (lvl == 1) {
+ pte |= ARM_V7S_CONT_SECTION;
+ } else if (lvl == 2) {
+ arm_v7s_iopte xn = pte & ARM_V7S_ATTR_XN(lvl);
+ arm_v7s_iopte tex = pte & ARM_V7S_CONT_PAGE_TEX_MASK;
+
+ pte ^= xn | tex;
+ pte |= (xn << ARM_V7S_CONT_PAGE_XN_SHIFT) |
+ (tex << ARM_V7S_CONT_PAGE_TEX_SHIFT);
+ pte ^= ARM_V7S_PTE_TYPE_PAGE | ARM_V7S_PTE_TYPE_CONT_PAGE;
+ }
+ return pte;
+}
+
+static arm_v7s_iopte arm_v7s_cont_to_pte(arm_v7s_iopte pte, int lvl)
+{
+ if (lvl == 1) {
+ pte &= ~ARM_V7S_CONT_SECTION;
+ } else if (lvl == 2) {
+ arm_v7s_iopte xn = pte & BIT(ARM_V7S_CONT_PAGE_XN_SHIFT);
+ arm_v7s_iopte tex = pte & (ARM_V7S_CONT_PAGE_TEX_MASK <<
+ ARM_V7S_CONT_PAGE_TEX_SHIFT);
+
+ pte ^= xn | tex;
+ pte |= (xn >> ARM_V7S_CONT_PAGE_XN_SHIFT) |
+ (tex >> ARM_V7S_CONT_PAGE_TEX_SHIFT);
+ pte ^= ARM_V7S_PTE_TYPE_PAGE | ARM_V7S_PTE_TYPE_CONT_PAGE;
+ }
+ return pte;
+}
+
+static bool arm_v7s_pte_is_cont(arm_v7s_iopte pte, int lvl)
+{
+ if (lvl == 1 && !ARM_V7S_PTE_IS_TABLE(pte, lvl))
+ return pte & ARM_V7S_CONT_SECTION;
+ else if (lvl == 2)
+ return !(pte & ARM_V7S_PTE_TYPE_PAGE);
+ return false;
+}
+
+static int __arm_v7s_unmap(struct arm_v7s_io_pgtable *, unsigned long,
+ size_t, int, arm_v7s_iopte *);
+
+static int arm_v7s_init_pte(struct arm_v7s_io_pgtable *data,
+ unsigned long iova, phys_addr_t paddr, int prot,
+ int lvl, int num_entries, arm_v7s_iopte *ptep)
+{
+ struct io_pgtable_cfg *cfg = &data->iop.cfg;
+ arm_v7s_iopte pte = arm_v7s_prot_to_pte(prot, lvl, cfg);
+ int i;
+
+ for (i = 0; i < num_entries; i++)
+ if (ARM_V7S_PTE_IS_TABLE(ptep[i], lvl)) {
+ /*
+ * We need to unmap and free the old table before
+ * overwriting it with a block entry.
+ */
+ arm_v7s_iopte *tblp;
+ size_t sz = ARM_V7S_BLOCK_SIZE(lvl);
+
+ tblp = ptep + i - ARM_V7S_LVL_IDX(iova, lvl);
+ if (WARN_ON(__arm_v7s_unmap(data, iova, sz, lvl, tblp)
+ != sz))
+ return -EINVAL;
+ } else if (ptep[i]) {
+ /* We require an unmap first */
+ WARN_ON(!selftest_running);
+ return -EEXIST;
+ }
+
+ pte |= ARM_V7S_PTE_TYPE_PAGE;
+ if (lvl == 1 && (cfg->quirks & IO_PGTABLE_QUIRK_ARM_NS))
+ pte |= ARM_V7S_ATTR_NS_SECTION;
+
+ if (num_entries > 1)
+ pte = arm_v7s_pte_to_cont(pte, lvl);
+
+ pte |= paddr & ARM_V7S_LVL_MASK(lvl);
+
+ __arm_v7s_set_pte(ptep, pte, num_entries, cfg);
+ return 0;
+}
+
+static int __arm_v7s_map(struct arm_v7s_io_pgtable *data, unsigned long iova,
+ phys_addr_t paddr, size_t size, int prot,
+ int lvl, arm_v7s_iopte *ptep)
+{
+ struct io_pgtable_cfg *cfg = &data->iop.cfg;
+ arm_v7s_iopte pte, *cptep;
+ int num_entries = size >> ARM_V7S_LVL_SHIFT(lvl);
+
+ /* Find our entry at the current level */
+ ptep += ARM_V7S_LVL_IDX(iova, lvl);
+
+ /* If we can install a leaf entry at this level, then do so */
+ if (num_entries)
+ return arm_v7s_init_pte(data, iova, paddr, prot,
+ lvl, num_entries, ptep);
+
+ /* We can't allocate tables at the final level */
+ if (WARN_ON(lvl == 2))
+ return -EINVAL;
+
+ /* Grab a pointer to the next level */
+ pte = *ptep;
+ if (!pte) {
+ cptep = __arm_v7s_alloc_table(lvl + 1, GFP_ATOMIC, data);
+ if (!cptep)
+ return -ENOMEM;
+
+ pte = virt_to_phys(cptep) | ARM_V7S_PTE_TYPE_TABLE;
+ if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_NS)
+ pte |= ARM_V7S_ATTR_NS_TABLE;
+
+ __arm_v7s_set_pte(ptep, pte, 1, cfg);
+ } else {
+ cptep = iopte_deref(pte, lvl);
+ }
+
+ /* Rinse, repeat */
+ return __arm_v7s_map(data, iova, paddr, size, prot, lvl + 1, cptep);
+}
+
+static int arm_v7s_map(struct io_pgtable_ops *ops, unsigned long iova,
+ phys_addr_t paddr, size_t size, int prot)
+{
+ struct arm_v7s_io_pgtable *data = io_pgtable_ops_to_data(ops);
+ struct io_pgtable_cfg *cfg = &data->iop.cfg;
+ const struct iommu_gather_ops *tlb = cfg->tlb;
+ void *cookie = data->iop.cookie;
+ int ret;
+
+ /* If no access, then nothing to do */
+ if (!(prot & (IOMMU_READ | IOMMU_WRITE)))
+ return 0;
+
+ ret = __arm_v7s_map(data, iova, paddr, size, prot, 1, data->pgd);
+ /*
+ * 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.
+ */
+ if (cfg->quirks & IO_PGTABLE_QUIRK_TLBI_ON_MAP) {
+ tlb->tlb_add_flush(iova, size, ARM_V7S_BLOCK_SIZE(2), false,
+ cookie);
+ tlb->tlb_sync(cookie);
+ } else {
+ wmb();
+ }
+
+ return ret;
+}
+
+static void arm_v7s_free_pgtable(struct io_pgtable *iop)
+{
+ struct arm_v7s_io_pgtable *data = io_pgtable_to_data(iop);
+ int i;
+
+ for (i = 0; i < ARM_V7S_PTES_PER_LVL(1); i++) {
+ arm_v7s_iopte pte = data->pgd[i];
+
+ if (ARM_V7S_PTE_IS_TABLE(pte, 1))
+ __arm_v7s_free_table(iopte_deref(pte, 1), 2, data);
+ }
+ __arm_v7s_free_table(data->pgd, 1, data);
+ kmem_cache_destroy(data->l2_tables);
+ kfree(data);
+}
+
+static void arm_v7s_split_cont(struct arm_v7s_io_pgtable *data,
+ unsigned long iova, int idx, int lvl,
+ arm_v7s_iopte *ptep)
+{
+ struct io_pgtable_cfg *cfg = &data->iop.cfg;
+ void *cookie = data->iop.cookie;
+ arm_v7s_iopte pte;
+ size_t size = ARM_V7S_BLOCK_SIZE(lvl);
+ int i;
+
+ ptep -= idx & (ARM_V7S_CONT_PAGES - 1);
+ pte = arm_v7s_cont_to_pte(*ptep, lvl);
+ for (i = 0; i < ARM_V7S_CONT_PAGES; i++) {
+ ptep[i] = pte;
+ pte += size;
+ }
+
+ __arm_v7s_pte_sync(ptep, ARM_V7S_CONT_PAGES, cfg);
+
+ size *= ARM_V7S_CONT_PAGES;
+ cfg->tlb->tlb_add_flush(iova, size, size, true, cookie);
+ cfg->tlb->tlb_sync(cookie);
+}
+
+static int arm_v7s_split_blk_unmap(struct arm_v7s_io_pgtable *data,
+ unsigned long iova, size_t size,
+ arm_v7s_iopte *ptep)
+{
+ unsigned long blk_start, blk_end, blk_size;
+ phys_addr_t blk_paddr;
+ arm_v7s_iopte table = 0;
+ struct io_pgtable_cfg *cfg = &data->iop.cfg;
+ int prot = arm_v7s_pte_to_prot(*ptep, 1);
+
+ blk_size = ARM_V7S_BLOCK_SIZE(1);
+ blk_start = iova & ARM_V7S_LVL_MASK(1);
+ blk_end = blk_start + ARM_V7S_BLOCK_SIZE(1);
+ blk_paddr = *ptep & ARM_V7S_LVL_MASK(1);
+
+ for (; blk_start < blk_end; blk_start += size, blk_paddr += size) {
+ arm_v7s_iopte *tablep;
+
+ /* Unmap! */
+ if (blk_start == iova)
+ continue;
+
+ /* __arm_v7s_map expects a pointer to the start of the table */
+ tablep = &table - ARM_V7S_LVL_IDX(blk_start, 1);
+ if (__arm_v7s_map(data, blk_start, blk_paddr, size, prot, 1,
+ tablep) < 0) {
+ if (table) {
+ /* Free the table we allocated */
+ tablep = iopte_deref(table, 1);
+ __arm_v7s_free_table(tablep, 2, data);
+ }
+ return 0; /* Bytes unmapped */
+ }
+ }
+
+ __arm_v7s_set_pte(ptep, table, 1, cfg);
+ iova &= ~(blk_size - 1);
+ cfg->tlb->tlb_add_flush(iova, blk_size, blk_size, true, data->iop.cookie);
+ return size;
+}
+
+static int __arm_v7s_unmap(struct arm_v7s_io_pgtable *data,
+ unsigned long iova, size_t size, int lvl,
+ arm_v7s_iopte *ptep)
+{
+ arm_v7s_iopte pte[ARM_V7S_CONT_PAGES];
+ struct io_pgtable_cfg *cfg = &data->iop.cfg;
+ const struct iommu_gather_ops *tlb = cfg->tlb;
+ void *cookie = data->iop.cookie;
+ int idx, i = 0, num_entries = size >> ARM_V7S_LVL_SHIFT(lvl);
+
+ /* Something went horribly wrong and we ran out of page table */
+ if (WARN_ON(lvl > 2))
+ return 0;
+
+ idx = ARM_V7S_LVL_IDX(iova, lvl);
+ ptep += idx;
+ do {
+ if (WARN_ON(!ARM_V7S_PTE_IS_VALID(ptep[i])))
+ return 0;
+ pte[i] = ptep[i];
+ } while (++i < num_entries);
+
+ /*
+ * If we've hit a contiguous 'large page' entry at this level, it
+ * needs splitting first, unless we're unmapping the whole lot.
+ */
+ if (num_entries <= 1 && arm_v7s_pte_is_cont(pte[0], lvl))
+ arm_v7s_split_cont(data, iova, idx, lvl, ptep);
+
+ /* If the size matches this level, we're in the right place */
+ if (num_entries) {
+ size_t blk_size = ARM_V7S_BLOCK_SIZE(lvl);
+
+ __arm_v7s_set_pte(ptep, 0, num_entries, cfg);
+
+ for (i = 0; i < num_entries; i++) {
+ if (ARM_V7S_PTE_IS_TABLE(pte[i], lvl)) {
+ /* Also flush any partial walks */
+ tlb->tlb_add_flush(iova, blk_size,
+ ARM_V7S_BLOCK_SIZE(2),
+ false, cookie);
+ tlb->tlb_sync(cookie);
+ ptep = iopte_deref(pte[i], lvl);
+ __arm_v7s_free_table(ptep, lvl + 1, data);
+ } else {
+ tlb->tlb_add_flush(iova, blk_size, blk_size,
+ true, cookie);
+ }
+ iova += blk_size;
+ }
+ return size;
+ } else if (lvl == 1 && !ARM_V7S_PTE_IS_TABLE(pte[0], lvl)) {
+ /*
+ * Insert a table at the next level to map the old region,
+ * minus the part we want to unmap
+ */
+ return arm_v7s_split_blk_unmap(data, iova, size, ptep);
+ }
+
+ /* Keep on walkin' */
+ ptep = iopte_deref(pte[0], lvl);
+ return __arm_v7s_unmap(data, iova, size, lvl + 1, ptep);
+}
+
+static int arm_v7s_unmap(struct io_pgtable_ops *ops, unsigned long iova,
+ size_t size)
+{
+ size_t unmapped;
+ struct arm_v7s_io_pgtable *data = io_pgtable_ops_to_data(ops);
+ struct io_pgtable *iop = &data->iop;
+
+ unmapped = __arm_v7s_unmap(data, iova, size, 1, data->pgd);
+ if (unmapped)
+ iop->cfg.tlb->tlb_sync(iop->cookie);
+
+ return unmapped;
+}
+
+static phys_addr_t arm_v7s_iova_to_phys(struct io_pgtable_ops *ops,
+ unsigned long iova)
+{
+ struct arm_v7s_io_pgtable *data = io_pgtable_ops_to_data(ops);
+ arm_v7s_iopte *ptep = data->pgd, pte = ARM_V7S_PTE_TYPE_TABLE;
+ int lvl = 0;
+ u32 mask;
+
+ while (ARM_V7S_PTE_IS_TABLE(pte, lvl)) {
+ pte = ptep[ARM_V7S_LVL_IDX(iova, ++lvl)];
+ ptep = iopte_deref(pte, lvl);
+ }
+ if (!ARM_V7S_PTE_IS_VALID(pte))
+ return 0;
+
+ mask = ARM_V7S_LVL_MASK(lvl);
+ if (arm_v7s_pte_is_cont(pte, lvl))
+ mask *= ARM_V7S_CONT_PAGES;
+ return (pte & mask) | (iova & ~mask);
+}
+
+static struct io_pgtable *arm_v7s_alloc_pgtable(struct io_pgtable_cfg *cfg,
+ void *cookie)
+{
+ struct arm_v7s_io_pgtable *data;
+
+ if (cfg->ias > ARM_V7S_ADDR_BITS || cfg->oas > ARM_V7S_ADDR_BITS)
+ return NULL;
+
+ data = kmalloc(sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return NULL;
+
+ data->l2_tables = kmem_cache_create("io-pgtable_armv7s_l2",
+ ARM_V7S_TABLE_SIZE(2),
+ ARM_V7S_TABLE_SIZE(2),
+ SLAB_CACHE_DMA, NULL);
+ if (!data->l2_tables)
+ goto out_free_data;
+
+ data->iop.ops = (struct io_pgtable_ops) {
+ .map = arm_v7s_map,
+ .unmap = arm_v7s_unmap,
+ .iova_to_phys = arm_v7s_iova_to_phys,
+ };
+
+ /* We have to do this early for __arm_v7s_alloc_table to work... */
+ data->iop.cfg = *cfg;
+
+ /*
+ * Unless the IOMMU driver indicates supersection support by
+ * having SZ_16M set in the initial bitmap, they won't be used.
+ */
+ cfg->pgsize_bitmap &= SZ_4K | SZ_64K | SZ_1M | SZ_16M;
+
+ /* TCR: T0SZ=0, disable TTBR1 */
+ cfg->arm_v7s_cfg.tcr = ARM_V7S_TCR_PD1;
+
+ /*
+ * TEX remap: the indices used map to the closest equivalent types
+ * under the non-TEX-remap interpretation of those attribute bits,
+ * excepting various implementation-defined aspects of shareability.
+ */
+ cfg->arm_v7s_cfg.prrr = ARM_V7S_PRRR_TR(1, ARM_V7S_PRRR_TYPE_DEVICE) |
+ ARM_V7S_PRRR_TR(4, ARM_V7S_PRRR_TYPE_NORMAL) |
+ ARM_V7S_PRRR_TR(7, ARM_V7S_PRRR_TYPE_NORMAL) |
+ ARM_V7S_PRRR_DS0 | ARM_V7S_PRRR_DS1 |
+ ARM_V7S_PRRR_NS1 | ARM_V7S_PRRR_NOS(7);
+ cfg->arm_v7s_cfg.nmrr = ARM_V7S_NMRR_IR(7, ARM_V7S_RGN_WBWA) |
+ ARM_V7S_NMRR_OR(7, ARM_V7S_RGN_WBWA);
+
+ /* Looking good; allocate a pgd */
+ data->pgd = __arm_v7s_alloc_table(1, GFP_KERNEL, data);
+ if (!data->pgd)
+ goto out_free_data;
+
+ /* Ensure the empty pgd is visible before any actual TTBR write */
+ wmb();
+
+ /* TTBRs */
+ cfg->arm_v7s_cfg.ttbr[0] = virt_to_phys(data->pgd) |
+ ARM_V7S_TTBR_S | ARM_V7S_TTBR_NOS |
+ ARM_V7S_TTBR_IRGN_ATTR(ARM_V7S_RGN_WBWA) |
+ ARM_V7S_TTBR_ORGN_ATTR(ARM_V7S_RGN_WBWA);
+ cfg->arm_v7s_cfg.ttbr[1] = 0;
+ return &data->iop;
+
+out_free_data:
+ kmem_cache_destroy(data->l2_tables);
+ kfree(data);
+ return NULL;
+}
+
+struct io_pgtable_init_fns io_pgtable_arm_v7s_init_fns = {
+ .alloc = arm_v7s_alloc_pgtable,
+ .free = arm_v7s_free_pgtable,
+};
+
+#ifdef CONFIG_IOMMU_IO_PGTABLE_ARMV7S_SELFTEST
+
+static struct io_pgtable_cfg *cfg_cookie;
+
+static void dummy_tlb_flush_all(void *cookie)
+{
+ WARN_ON(cookie != cfg_cookie);
+}
+
+static void dummy_tlb_add_flush(unsigned long iova, size_t size,
+ size_t granule, bool leaf, void *cookie)
+{
+ WARN_ON(cookie != cfg_cookie);
+ WARN_ON(!(size & cfg_cookie->pgsize_bitmap));
+}
+
+static void dummy_tlb_sync(void *cookie)
+{
+ WARN_ON(cookie != cfg_cookie);
+}
+
+static struct iommu_gather_ops dummy_tlb_ops = {
+ .tlb_flush_all = dummy_tlb_flush_all,
+ .tlb_add_flush = dummy_tlb_add_flush,
+ .tlb_sync = dummy_tlb_sync,
+};
+
+#define __FAIL(ops) ({ \
+ WARN(1, "selftest: test failed\n"); \
+ selftest_running = false; \
+ -EFAULT; \
+})
+
+static int __init arm_v7s_do_selftests(void)
+{
+ struct io_pgtable_ops *ops;
+ struct io_pgtable_cfg cfg = {
+ .tlb = &dummy_tlb_ops,
+ .oas = 32,
+ .ias = 32,
+ .quirks = IO_PGTABLE_QUIRK_ARM_NS,
+ .pgsize_bitmap = SZ_4K | SZ_64K | SZ_1M | SZ_16M,
+ };
+ unsigned int iova, size, iova_start;
+ unsigned int i, loopnr = 0;
+
+ selftest_running = true;
+
+ cfg_cookie = &cfg;
+
+ ops = alloc_io_pgtable_ops(ARM_V7S, &cfg, &cfg);
+ if (!ops) {
+ pr_err("selftest: failed to allocate io pgtable ops\n");
+ return -EINVAL;
+ }
+
+ /*
+ * Initial sanity checks.
+ * Empty page tables shouldn't provide any translations.
+ */
+ if (ops->iova_to_phys(ops, 42))
+ return __FAIL(ops);
+
+ if (ops->iova_to_phys(ops, SZ_1G + 42))
+ return __FAIL(ops);
+
+ if (ops->iova_to_phys(ops, SZ_2G + 42))
+ return __FAIL(ops);
+
+ /*
+ * Distinct mappings of different granule sizes.
+ */
+ iova = 0;
+ i = find_first_bit(&cfg.pgsize_bitmap, BITS_PER_LONG);
+ while (i != BITS_PER_LONG) {
+ size = 1UL << i;
+ if (ops->map(ops, iova, iova, size, IOMMU_READ |
+ IOMMU_WRITE |
+ IOMMU_NOEXEC |
+ IOMMU_CACHE))
+ return __FAIL(ops);
+
+ /* Overlapping mappings */
+ if (!ops->map(ops, iova, iova + size, size,
+ IOMMU_READ | IOMMU_NOEXEC))
+ return __FAIL(ops);
+
+ if (ops->iova_to_phys(ops, iova + 42) != (iova + 42))
+ return __FAIL(ops);
+
+ iova += SZ_16M;
+ i++;
+ i = find_next_bit(&cfg.pgsize_bitmap, BITS_PER_LONG, i);
+ loopnr++;
+ }
+
+ /* Partial unmap */
+ i = 1;
+ size = 1UL << __ffs(cfg.pgsize_bitmap);
+ while (i < loopnr) {
+ iova_start = i * SZ_16M;
+ if (ops->unmap(ops, iova_start + size, size) != size)
+ return __FAIL(ops);
+
+ /* Remap of partial unmap */
+ if (ops->map(ops, iova_start + size, size, size, IOMMU_READ))
+ return __FAIL(ops);
+
+ if (ops->iova_to_phys(ops, iova_start + size + 42)
+ != (size + 42))
+ return __FAIL(ops);
+ i++;
+ }
+
+ /* Full unmap */
+ iova = 0;
+ i = find_first_bit(&cfg.pgsize_bitmap, BITS_PER_LONG);
+ while (i != BITS_PER_LONG) {
+ size = 1UL << i;
+
+ if (ops->unmap(ops, iova, size) != size)
+ return __FAIL(ops);
+
+ if (ops->iova_to_phys(ops, iova + 42))
+ return __FAIL(ops);
+
+ /* Remap full block */
+ if (ops->map(ops, iova, iova, size, IOMMU_WRITE))
+ return __FAIL(ops);
+
+ if (ops->iova_to_phys(ops, iova + 42) != (iova + 42))
+ return __FAIL(ops);
+
+ iova += SZ_16M;
+ i++;
+ i = find_next_bit(&cfg.pgsize_bitmap, BITS_PER_LONG, i);
+ }
+
+ free_io_pgtable_ops(ops);
+
+ selftest_running = false;
+
+ pr_info("self test ok\n");
+ return 0;
+}
+subsys_initcall(arm_v7s_do_selftests);
+#endif
diff --git a/drivers/iommu/io-pgtable.c b/drivers/iommu/io-pgtable.c
index 6f2e319..8c615b7 100644
--- a/drivers/iommu/io-pgtable.c
+++ b/drivers/iommu/io-pgtable.c
@@ -33,6 +33,9 @@ io_pgtable_init_table[IO_PGTABLE_NUM_FMTS] =
[ARM_64_LPAE_S1] = &io_pgtable_arm_64_lpae_s1_init_fns,
[ARM_64_LPAE_S2] = &io_pgtable_arm_64_lpae_s2_init_fns,
#endif
+#ifdef CONFIG_IOMMU_IO_PGTABLE_ARMV7S
+ [ARM_V7S] = &io_pgtable_arm_v7s_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 36673c8..aa57073 100644
--- a/drivers/iommu/io-pgtable.h
+++ b/drivers/iommu/io-pgtable.h
@@ -1,5 +1,6 @@
#ifndef __IO_PGTABLE_H
#define __IO_PGTABLE_H
+#include <linux/bitops.h>
/*
* Public API for use by IOMMU drivers
@@ -9,6 +10,7 @@ enum io_pgtable_fmt {
ARM_32_LPAE_S2,
ARM_64_LPAE_S1,
ARM_64_LPAE_S2,
+ ARM_V7S,
IO_PGTABLE_NUM_FMTS,
};
@@ -45,7 +47,9 @@ struct iommu_gather_ops {
* page table walker.
*/
struct io_pgtable_cfg {
- #define IO_PGTABLE_QUIRK_ARM_NS (1 << 0) /* Set NS bit in PTEs */
+ #define IO_PGTABLE_QUIRK_ARM_NS BIT(0) /* Set NS bit in PTEs */
+ #define IO_PGTABLE_QUIRK_NO_PERMS BIT(1) /* No AP/XN bits */
+ #define IO_PGTABLE_QUIRK_TLBI_ON_MAP BIT(2) /* TLB Inv. on map */
int quirks;
unsigned long pgsize_bitmap;
unsigned int ias;
@@ -65,6 +69,13 @@ struct io_pgtable_cfg {
u64 vttbr;
u64 vtcr;
} arm_lpae_s2_cfg;
+
+ struct {
+ u32 ttbr[2];
+ u32 tcr;
+ u32 nmrr;
+ u32 prrr;
+ } arm_v7s_cfg;
};
};
@@ -149,5 +160,6 @@ extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s1_init_fns;
extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s2_init_fns;
extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s1_init_fns;
extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s2_init_fns;
+extern struct io_pgtable_init_fns io_pgtable_arm_v7s_init_fns;
#endif /* __IO_PGTABLE_H */
--
1.9.1
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