Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / iommu / arm-smmu.c
diff --git a/kernel/drivers/iommu/arm-smmu.c b/kernel/drivers/iommu/arm-smmu.c
new file mode 100644 (file)
index 0000000..65075ef
--- /dev/null
@@ -0,0 +1,1916 @@
+/*
+ * IOMMU API for ARM architected SMMU implementations.
+ *
+ * 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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Copyright (C) 2013 ARM Limited
+ *
+ * Author: Will Deacon <will.deacon@arm.com>
+ *
+ * This driver currently supports:
+ *     - SMMUv1 and v2 implementations
+ *     - Stream-matching and stream-indexing
+ *     - v7/v8 long-descriptor format
+ *     - Non-secure access to the SMMU
+ *     - Context fault reporting
+ */
+
+#define pr_fmt(fmt) "arm-smmu: " fmt
+
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/iommu.h>
+#include <linux/iopoll.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+#include <linux/amba/bus.h>
+
+#include "io-pgtable.h"
+
+/* Maximum number of stream IDs assigned to a single device */
+#define MAX_MASTER_STREAMIDS           MAX_PHANDLE_ARGS
+
+/* Maximum number of context banks per SMMU */
+#define ARM_SMMU_MAX_CBS               128
+
+/* Maximum number of mapping groups per SMMU */
+#define ARM_SMMU_MAX_SMRS              128
+
+/* SMMU global address space */
+#define ARM_SMMU_GR0(smmu)             ((smmu)->base)
+#define ARM_SMMU_GR1(smmu)             ((smmu)->base + (1 << (smmu)->pgshift))
+
+/*
+ * SMMU global address space with conditional offset to access secure
+ * aliases of non-secure registers (e.g. nsCR0: 0x400, nsGFSR: 0x448,
+ * nsGFSYNR0: 0x450)
+ */
+#define ARM_SMMU_GR0_NS(smmu)                                          \
+       ((smmu)->base +                                                 \
+               ((smmu->options & ARM_SMMU_OPT_SECURE_CFG_ACCESS)       \
+                       ? 0x400 : 0))
+
+/* Configuration registers */
+#define ARM_SMMU_GR0_sCR0              0x0
+#define sCR0_CLIENTPD                  (1 << 0)
+#define sCR0_GFRE                      (1 << 1)
+#define sCR0_GFIE                      (1 << 2)
+#define sCR0_GCFGFRE                   (1 << 4)
+#define sCR0_GCFGFIE                   (1 << 5)
+#define sCR0_USFCFG                    (1 << 10)
+#define sCR0_VMIDPNE                   (1 << 11)
+#define sCR0_PTM                       (1 << 12)
+#define sCR0_FB                                (1 << 13)
+#define sCR0_BSU_SHIFT                 14
+#define sCR0_BSU_MASK                  0x3
+
+/* Identification registers */
+#define ARM_SMMU_GR0_ID0               0x20
+#define ARM_SMMU_GR0_ID1               0x24
+#define ARM_SMMU_GR0_ID2               0x28
+#define ARM_SMMU_GR0_ID3               0x2c
+#define ARM_SMMU_GR0_ID4               0x30
+#define ARM_SMMU_GR0_ID5               0x34
+#define ARM_SMMU_GR0_ID6               0x38
+#define ARM_SMMU_GR0_ID7               0x3c
+#define ARM_SMMU_GR0_sGFSR             0x48
+#define ARM_SMMU_GR0_sGFSYNR0          0x50
+#define ARM_SMMU_GR0_sGFSYNR1          0x54
+#define ARM_SMMU_GR0_sGFSYNR2          0x58
+
+#define ID0_S1TS                       (1 << 30)
+#define ID0_S2TS                       (1 << 29)
+#define ID0_NTS                                (1 << 28)
+#define ID0_SMS                                (1 << 27)
+#define ID0_ATOSNS                     (1 << 26)
+#define ID0_CTTW                       (1 << 14)
+#define ID0_NUMIRPT_SHIFT              16
+#define ID0_NUMIRPT_MASK               0xff
+#define ID0_NUMSIDB_SHIFT              9
+#define ID0_NUMSIDB_MASK               0xf
+#define ID0_NUMSMRG_SHIFT              0
+#define ID0_NUMSMRG_MASK               0xff
+
+#define ID1_PAGESIZE                   (1 << 31)
+#define ID1_NUMPAGENDXB_SHIFT          28
+#define ID1_NUMPAGENDXB_MASK           7
+#define ID1_NUMS2CB_SHIFT              16
+#define ID1_NUMS2CB_MASK               0xff
+#define ID1_NUMCB_SHIFT                        0
+#define ID1_NUMCB_MASK                 0xff
+
+#define ID2_OAS_SHIFT                  4
+#define ID2_OAS_MASK                   0xf
+#define ID2_IAS_SHIFT                  0
+#define ID2_IAS_MASK                   0xf
+#define ID2_UBS_SHIFT                  8
+#define ID2_UBS_MASK                   0xf
+#define ID2_PTFS_4K                    (1 << 12)
+#define ID2_PTFS_16K                   (1 << 13)
+#define ID2_PTFS_64K                   (1 << 14)
+
+/* Global TLB invalidation */
+#define ARM_SMMU_GR0_TLBIVMID          0x64
+#define ARM_SMMU_GR0_TLBIALLNSNH       0x68
+#define ARM_SMMU_GR0_TLBIALLH          0x6c
+#define ARM_SMMU_GR0_sTLBGSYNC         0x70
+#define ARM_SMMU_GR0_sTLBGSTATUS       0x74
+#define sTLBGSTATUS_GSACTIVE           (1 << 0)
+#define TLB_LOOP_TIMEOUT               1000000 /* 1s! */
+
+/* Stream mapping registers */
+#define ARM_SMMU_GR0_SMR(n)            (0x800 + ((n) << 2))
+#define SMR_VALID                      (1 << 31)
+#define SMR_MASK_SHIFT                 16
+#define SMR_MASK_MASK                  0x7fff
+#define SMR_ID_SHIFT                   0
+#define SMR_ID_MASK                    0x7fff
+
+#define ARM_SMMU_GR0_S2CR(n)           (0xc00 + ((n) << 2))
+#define S2CR_CBNDX_SHIFT               0
+#define S2CR_CBNDX_MASK                        0xff
+#define S2CR_TYPE_SHIFT                        16
+#define S2CR_TYPE_MASK                 0x3
+#define S2CR_TYPE_TRANS                        (0 << S2CR_TYPE_SHIFT)
+#define S2CR_TYPE_BYPASS               (1 << S2CR_TYPE_SHIFT)
+#define S2CR_TYPE_FAULT                        (2 << S2CR_TYPE_SHIFT)
+
+/* Context bank attribute registers */
+#define ARM_SMMU_GR1_CBAR(n)           (0x0 + ((n) << 2))
+#define CBAR_VMID_SHIFT                        0
+#define CBAR_VMID_MASK                 0xff
+#define CBAR_S1_BPSHCFG_SHIFT          8
+#define CBAR_S1_BPSHCFG_MASK           3
+#define CBAR_S1_BPSHCFG_NSH            3
+#define CBAR_S1_MEMATTR_SHIFT          12
+#define CBAR_S1_MEMATTR_MASK           0xf
+#define CBAR_S1_MEMATTR_WB             0xf
+#define CBAR_TYPE_SHIFT                        16
+#define CBAR_TYPE_MASK                 0x3
+#define CBAR_TYPE_S2_TRANS             (0 << CBAR_TYPE_SHIFT)
+#define CBAR_TYPE_S1_TRANS_S2_BYPASS   (1 << CBAR_TYPE_SHIFT)
+#define CBAR_TYPE_S1_TRANS_S2_FAULT    (2 << CBAR_TYPE_SHIFT)
+#define CBAR_TYPE_S1_TRANS_S2_TRANS    (3 << CBAR_TYPE_SHIFT)
+#define CBAR_IRPTNDX_SHIFT             24
+#define CBAR_IRPTNDX_MASK              0xff
+
+#define ARM_SMMU_GR1_CBA2R(n)          (0x800 + ((n) << 2))
+#define CBA2R_RW64_32BIT               (0 << 0)
+#define CBA2R_RW64_64BIT               (1 << 0)
+
+/* Translation context bank */
+#define ARM_SMMU_CB_BASE(smmu)         ((smmu)->base + ((smmu)->size >> 1))
+#define ARM_SMMU_CB(smmu, n)           ((n) * (1 << (smmu)->pgshift))
+
+#define ARM_SMMU_CB_SCTLR              0x0
+#define ARM_SMMU_CB_RESUME             0x8
+#define ARM_SMMU_CB_TTBCR2             0x10
+#define ARM_SMMU_CB_TTBR0_LO           0x20
+#define ARM_SMMU_CB_TTBR0_HI           0x24
+#define ARM_SMMU_CB_TTBR1_LO           0x28
+#define ARM_SMMU_CB_TTBR1_HI           0x2c
+#define ARM_SMMU_CB_TTBCR              0x30
+#define ARM_SMMU_CB_S1_MAIR0           0x38
+#define ARM_SMMU_CB_S1_MAIR1           0x3c
+#define ARM_SMMU_CB_PAR_LO             0x50
+#define ARM_SMMU_CB_PAR_HI             0x54
+#define ARM_SMMU_CB_FSR                        0x58
+#define ARM_SMMU_CB_FAR_LO             0x60
+#define ARM_SMMU_CB_FAR_HI             0x64
+#define ARM_SMMU_CB_FSYNR0             0x68
+#define ARM_SMMU_CB_S1_TLBIVA          0x600
+#define ARM_SMMU_CB_S1_TLBIASID                0x610
+#define ARM_SMMU_CB_S1_TLBIVAL         0x620
+#define ARM_SMMU_CB_S2_TLBIIPAS2       0x630
+#define ARM_SMMU_CB_S2_TLBIIPAS2L      0x638
+#define ARM_SMMU_CB_ATS1PR_LO          0x800
+#define ARM_SMMU_CB_ATS1PR_HI          0x804
+#define ARM_SMMU_CB_ATSR               0x8f0
+
+#define SCTLR_S1_ASIDPNE               (1 << 12)
+#define SCTLR_CFCFG                    (1 << 7)
+#define SCTLR_CFIE                     (1 << 6)
+#define SCTLR_CFRE                     (1 << 5)
+#define SCTLR_E                                (1 << 4)
+#define SCTLR_AFE                      (1 << 2)
+#define SCTLR_TRE                      (1 << 1)
+#define SCTLR_M                                (1 << 0)
+#define SCTLR_EAE_SBOP                 (SCTLR_AFE | SCTLR_TRE)
+
+#define CB_PAR_F                       (1 << 0)
+
+#define ATSR_ACTIVE                    (1 << 0)
+
+#define RESUME_RETRY                   (0 << 0)
+#define RESUME_TERMINATE               (1 << 0)
+
+#define TTBCR2_SEP_SHIFT               15
+#define TTBCR2_SEP_UPSTREAM            (0x7 << TTBCR2_SEP_SHIFT)
+
+#define TTBRn_HI_ASID_SHIFT            16
+
+#define FSR_MULTI                      (1 << 31)
+#define FSR_SS                         (1 << 30)
+#define FSR_UUT                                (1 << 8)
+#define FSR_ASF                                (1 << 7)
+#define FSR_TLBLKF                     (1 << 6)
+#define FSR_TLBMCF                     (1 << 5)
+#define FSR_EF                         (1 << 4)
+#define FSR_PF                         (1 << 3)
+#define FSR_AFF                                (1 << 2)
+#define FSR_TF                         (1 << 1)
+
+#define FSR_IGN                                (FSR_AFF | FSR_ASF | \
+                                        FSR_TLBMCF | FSR_TLBLKF)
+#define FSR_FAULT                      (FSR_MULTI | FSR_SS | FSR_UUT | \
+                                        FSR_EF | FSR_PF | FSR_TF | FSR_IGN)
+
+#define FSYNR0_WNR                     (1 << 4)
+
+static int force_stage;
+module_param_named(force_stage, force_stage, int, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(force_stage,
+       "Force SMMU mappings to be installed at a particular stage of translation. A value of '1' or '2' forces the corresponding stage. All other values are ignored (i.e. no stage is forced). Note that selecting a specific stage will disable support for nested translation.");
+
+enum arm_smmu_arch_version {
+       ARM_SMMU_V1 = 1,
+       ARM_SMMU_V2,
+};
+
+struct arm_smmu_smr {
+       u8                              idx;
+       u16                             mask;
+       u16                             id;
+};
+
+struct arm_smmu_master_cfg {
+       int                             num_streamids;
+       u16                             streamids[MAX_MASTER_STREAMIDS];
+       struct arm_smmu_smr             *smrs;
+};
+
+struct arm_smmu_master {
+       struct device_node              *of_node;
+       struct rb_node                  node;
+       struct arm_smmu_master_cfg      cfg;
+};
+
+struct arm_smmu_device {
+       struct device                   *dev;
+
+       void __iomem                    *base;
+       unsigned long                   size;
+       unsigned long                   pgshift;
+
+#define ARM_SMMU_FEAT_COHERENT_WALK    (1 << 0)
+#define ARM_SMMU_FEAT_STREAM_MATCH     (1 << 1)
+#define ARM_SMMU_FEAT_TRANS_S1         (1 << 2)
+#define ARM_SMMU_FEAT_TRANS_S2         (1 << 3)
+#define ARM_SMMU_FEAT_TRANS_NESTED     (1 << 4)
+#define ARM_SMMU_FEAT_TRANS_OPS                (1 << 5)
+       u32                             features;
+
+#define ARM_SMMU_OPT_SECURE_CFG_ACCESS (1 << 0)
+       u32                             options;
+       enum arm_smmu_arch_version      version;
+
+       u32                             num_context_banks;
+       u32                             num_s2_context_banks;
+       DECLARE_BITMAP(context_map, ARM_SMMU_MAX_CBS);
+       atomic_t                        irptndx;
+
+       u32                             num_mapping_groups;
+       DECLARE_BITMAP(smr_map, ARM_SMMU_MAX_SMRS);
+
+       unsigned long                   va_size;
+       unsigned long                   ipa_size;
+       unsigned long                   pa_size;
+
+       u32                             num_global_irqs;
+       u32                             num_context_irqs;
+       unsigned int                    *irqs;
+
+       struct list_head                list;
+       struct rb_root                  masters;
+};
+
+struct arm_smmu_cfg {
+       u8                              cbndx;
+       u8                              irptndx;
+       u32                             cbar;
+};
+#define INVALID_IRPTNDX                        0xff
+
+#define ARM_SMMU_CB_ASID(cfg)          ((cfg)->cbndx)
+#define ARM_SMMU_CB_VMID(cfg)          ((cfg)->cbndx + 1)
+
+enum arm_smmu_domain_stage {
+       ARM_SMMU_DOMAIN_S1 = 0,
+       ARM_SMMU_DOMAIN_S2,
+       ARM_SMMU_DOMAIN_NESTED,
+};
+
+struct arm_smmu_domain {
+       struct arm_smmu_device          *smmu;
+       struct io_pgtable_ops           *pgtbl_ops;
+       spinlock_t                      pgtbl_lock;
+       struct arm_smmu_cfg             cfg;
+       enum arm_smmu_domain_stage      stage;
+       struct mutex                    init_mutex; /* Protects smmu pointer */
+       struct iommu_domain             domain;
+};
+
+static struct iommu_ops arm_smmu_ops;
+
+static DEFINE_SPINLOCK(arm_smmu_devices_lock);
+static LIST_HEAD(arm_smmu_devices);
+
+struct arm_smmu_option_prop {
+       u32 opt;
+       const char *prop;
+};
+
+static struct arm_smmu_option_prop arm_smmu_options[] = {
+       { ARM_SMMU_OPT_SECURE_CFG_ACCESS, "calxeda,smmu-secure-config-access" },
+       { 0, NULL},
+};
+
+static struct arm_smmu_domain *to_smmu_domain(struct iommu_domain *dom)
+{
+       return container_of(dom, struct arm_smmu_domain, domain);
+}
+
+static void parse_driver_options(struct arm_smmu_device *smmu)
+{
+       int i = 0;
+
+       do {
+               if (of_property_read_bool(smmu->dev->of_node,
+                                               arm_smmu_options[i].prop)) {
+                       smmu->options |= arm_smmu_options[i].opt;
+                       dev_notice(smmu->dev, "option %s\n",
+                               arm_smmu_options[i].prop);
+               }
+       } while (arm_smmu_options[++i].opt);
+}
+
+static struct device_node *dev_get_dev_node(struct device *dev)
+{
+       if (dev_is_pci(dev)) {
+               struct pci_bus *bus = to_pci_dev(dev)->bus;
+
+               while (!pci_is_root_bus(bus))
+                       bus = bus->parent;
+               return bus->bridge->parent->of_node;
+       }
+
+       return dev->of_node;
+}
+
+static struct arm_smmu_master *find_smmu_master(struct arm_smmu_device *smmu,
+                                               struct device_node *dev_node)
+{
+       struct rb_node *node = smmu->masters.rb_node;
+
+       while (node) {
+               struct arm_smmu_master *master;
+
+               master = container_of(node, struct arm_smmu_master, node);
+
+               if (dev_node < master->of_node)
+                       node = node->rb_left;
+               else if (dev_node > master->of_node)
+                       node = node->rb_right;
+               else
+                       return master;
+       }
+
+       return NULL;
+}
+
+static struct arm_smmu_master_cfg *
+find_smmu_master_cfg(struct device *dev)
+{
+       struct arm_smmu_master_cfg *cfg = NULL;
+       struct iommu_group *group = iommu_group_get(dev);
+
+       if (group) {
+               cfg = iommu_group_get_iommudata(group);
+               iommu_group_put(group);
+       }
+
+       return cfg;
+}
+
+static int insert_smmu_master(struct arm_smmu_device *smmu,
+                             struct arm_smmu_master *master)
+{
+       struct rb_node **new, *parent;
+
+       new = &smmu->masters.rb_node;
+       parent = NULL;
+       while (*new) {
+               struct arm_smmu_master *this
+                       = container_of(*new, struct arm_smmu_master, node);
+
+               parent = *new;
+               if (master->of_node < this->of_node)
+                       new = &((*new)->rb_left);
+               else if (master->of_node > this->of_node)
+                       new = &((*new)->rb_right);
+               else
+                       return -EEXIST;
+       }
+
+       rb_link_node(&master->node, parent, new);
+       rb_insert_color(&master->node, &smmu->masters);
+       return 0;
+}
+
+static int register_smmu_master(struct arm_smmu_device *smmu,
+                               struct device *dev,
+                               struct of_phandle_args *masterspec)
+{
+       int i;
+       struct arm_smmu_master *master;
+
+       master = find_smmu_master(smmu, masterspec->np);
+       if (master) {
+               dev_err(dev,
+                       "rejecting multiple registrations for master device %s\n",
+                       masterspec->np->name);
+               return -EBUSY;
+       }
+
+       if (masterspec->args_count > MAX_MASTER_STREAMIDS) {
+               dev_err(dev,
+                       "reached maximum number (%d) of stream IDs for master device %s\n",
+                       MAX_MASTER_STREAMIDS, masterspec->np->name);
+               return -ENOSPC;
+       }
+
+       master = devm_kzalloc(dev, sizeof(*master), GFP_KERNEL);
+       if (!master)
+               return -ENOMEM;
+
+       master->of_node                 = masterspec->np;
+       master->cfg.num_streamids       = masterspec->args_count;
+
+       for (i = 0; i < master->cfg.num_streamids; ++i) {
+               u16 streamid = masterspec->args[i];
+
+               if (!(smmu->features & ARM_SMMU_FEAT_STREAM_MATCH) &&
+                    (streamid >= smmu->num_mapping_groups)) {
+                       dev_err(dev,
+                               "stream ID for master device %s greater than maximum allowed (%d)\n",
+                               masterspec->np->name, smmu->num_mapping_groups);
+                       return -ERANGE;
+               }
+               master->cfg.streamids[i] = streamid;
+       }
+       return insert_smmu_master(smmu, master);
+}
+
+static struct arm_smmu_device *find_smmu_for_device(struct device *dev)
+{
+       struct arm_smmu_device *smmu;
+       struct arm_smmu_master *master = NULL;
+       struct device_node *dev_node = dev_get_dev_node(dev);
+
+       spin_lock(&arm_smmu_devices_lock);
+       list_for_each_entry(smmu, &arm_smmu_devices, list) {
+               master = find_smmu_master(smmu, dev_node);
+               if (master)
+                       break;
+       }
+       spin_unlock(&arm_smmu_devices_lock);
+
+       return master ? smmu : NULL;
+}
+
+static int __arm_smmu_alloc_bitmap(unsigned long *map, int start, int end)
+{
+       int idx;
+
+       do {
+               idx = find_next_zero_bit(map, end, start);
+               if (idx == end)
+                       return -ENOSPC;
+       } while (test_and_set_bit(idx, map));
+
+       return idx;
+}
+
+static void __arm_smmu_free_bitmap(unsigned long *map, int idx)
+{
+       clear_bit(idx, map);
+}
+
+/* Wait for any pending TLB invalidations to complete */
+static void __arm_smmu_tlb_sync(struct arm_smmu_device *smmu)
+{
+       int count = 0;
+       void __iomem *gr0_base = ARM_SMMU_GR0(smmu);
+
+       writel_relaxed(0, gr0_base + ARM_SMMU_GR0_sTLBGSYNC);
+       while (readl_relaxed(gr0_base + ARM_SMMU_GR0_sTLBGSTATUS)
+              & sTLBGSTATUS_GSACTIVE) {
+               cpu_relax();
+               if (++count == TLB_LOOP_TIMEOUT) {
+                       dev_err_ratelimited(smmu->dev,
+                       "TLB sync timed out -- SMMU may be deadlocked\n");
+                       return;
+               }
+               udelay(1);
+       }
+}
+
+static void arm_smmu_tlb_sync(void *cookie)
+{
+       struct arm_smmu_domain *smmu_domain = cookie;
+       __arm_smmu_tlb_sync(smmu_domain->smmu);
+}
+
+static void arm_smmu_tlb_inv_context(void *cookie)
+{
+       struct arm_smmu_domain *smmu_domain = cookie;
+       struct arm_smmu_cfg *cfg = &smmu_domain->cfg;
+       struct arm_smmu_device *smmu = smmu_domain->smmu;
+       bool stage1 = cfg->cbar != CBAR_TYPE_S2_TRANS;
+       void __iomem *base;
+
+       if (stage1) {
+               base = ARM_SMMU_CB_BASE(smmu) + ARM_SMMU_CB(smmu, cfg->cbndx);
+               writel_relaxed(ARM_SMMU_CB_ASID(cfg),
+                              base + ARM_SMMU_CB_S1_TLBIASID);
+       } else {
+               base = ARM_SMMU_GR0(smmu);
+               writel_relaxed(ARM_SMMU_CB_VMID(cfg),
+                              base + ARM_SMMU_GR0_TLBIVMID);
+       }
+
+       __arm_smmu_tlb_sync(smmu);
+}
+
+static void arm_smmu_tlb_inv_range_nosync(unsigned long iova, size_t size,
+                                         bool leaf, void *cookie)
+{
+       struct arm_smmu_domain *smmu_domain = cookie;
+       struct arm_smmu_cfg *cfg = &smmu_domain->cfg;
+       struct arm_smmu_device *smmu = smmu_domain->smmu;
+       bool stage1 = cfg->cbar != CBAR_TYPE_S2_TRANS;
+       void __iomem *reg;
+
+       if (stage1) {
+               reg = ARM_SMMU_CB_BASE(smmu) + ARM_SMMU_CB(smmu, cfg->cbndx);
+               reg += leaf ? ARM_SMMU_CB_S1_TLBIVAL : ARM_SMMU_CB_S1_TLBIVA;
+
+               if (!IS_ENABLED(CONFIG_64BIT) || smmu->version == ARM_SMMU_V1) {
+                       iova &= ~12UL;
+                       iova |= ARM_SMMU_CB_ASID(cfg);
+                       writel_relaxed(iova, reg);
+#ifdef CONFIG_64BIT
+               } else {
+                       iova >>= 12;
+                       iova |= (u64)ARM_SMMU_CB_ASID(cfg) << 48;
+                       writeq_relaxed(iova, reg);
+#endif
+               }
+#ifdef CONFIG_64BIT
+       } else if (smmu->version == ARM_SMMU_V2) {
+               reg = ARM_SMMU_CB_BASE(smmu) + ARM_SMMU_CB(smmu, cfg->cbndx);
+               reg += leaf ? ARM_SMMU_CB_S2_TLBIIPAS2L :
+                             ARM_SMMU_CB_S2_TLBIIPAS2;
+               writeq_relaxed(iova >> 12, reg);
+#endif
+       } else {
+               reg = ARM_SMMU_GR0(smmu) + ARM_SMMU_GR0_TLBIVMID;
+               writel_relaxed(ARM_SMMU_CB_VMID(cfg), reg);
+       }
+}
+
+static void arm_smmu_flush_pgtable(void *addr, size_t size, void *cookie)
+{
+       struct arm_smmu_domain *smmu_domain = cookie;
+       struct arm_smmu_device *smmu = smmu_domain->smmu;
+       unsigned long offset = (unsigned long)addr & ~PAGE_MASK;
+
+
+       /* Ensure new page tables are visible to the hardware walker */
+       if (smmu->features & ARM_SMMU_FEAT_COHERENT_WALK) {
+               dsb(ishst);
+       } else {
+               /*
+                * If the SMMU can't walk tables in the CPU caches, treat them
+                * like non-coherent DMA since we need to flush the new entries
+                * all the way out to memory. There's no possibility of
+                * recursion here as the SMMU table walker will not be wired
+                * through another SMMU.
+                */
+               dma_map_page(smmu->dev, virt_to_page(addr), offset, size,
+                            DMA_TO_DEVICE);
+       }
+}
+
+static struct iommu_gather_ops arm_smmu_gather_ops = {
+       .tlb_flush_all  = arm_smmu_tlb_inv_context,
+       .tlb_add_flush  = arm_smmu_tlb_inv_range_nosync,
+       .tlb_sync       = arm_smmu_tlb_sync,
+       .flush_pgtable  = arm_smmu_flush_pgtable,
+};
+
+static irqreturn_t arm_smmu_context_fault(int irq, void *dev)
+{
+       int flags, ret;
+       u32 fsr, far, fsynr, resume;
+       unsigned long iova;
+       struct iommu_domain *domain = dev;
+       struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+       struct arm_smmu_cfg *cfg = &smmu_domain->cfg;
+       struct arm_smmu_device *smmu = smmu_domain->smmu;
+       void __iomem *cb_base;
+
+       cb_base = ARM_SMMU_CB_BASE(smmu) + ARM_SMMU_CB(smmu, cfg->cbndx);
+       fsr = readl_relaxed(cb_base + ARM_SMMU_CB_FSR);
+
+       if (!(fsr & FSR_FAULT))
+               return IRQ_NONE;
+
+       if (fsr & FSR_IGN)
+               dev_err_ratelimited(smmu->dev,
+                                   "Unexpected context fault (fsr 0x%x)\n",
+                                   fsr);
+
+       fsynr = readl_relaxed(cb_base + ARM_SMMU_CB_FSYNR0);
+       flags = fsynr & FSYNR0_WNR ? IOMMU_FAULT_WRITE : IOMMU_FAULT_READ;
+
+       far = readl_relaxed(cb_base + ARM_SMMU_CB_FAR_LO);
+       iova = far;
+#ifdef CONFIG_64BIT
+       far = readl_relaxed(cb_base + ARM_SMMU_CB_FAR_HI);
+       iova |= ((unsigned long)far << 32);
+#endif
+
+       if (!report_iommu_fault(domain, smmu->dev, iova, flags)) {
+               ret = IRQ_HANDLED;
+               resume = RESUME_RETRY;
+       } else {
+               dev_err_ratelimited(smmu->dev,
+                   "Unhandled context fault: iova=0x%08lx, fsynr=0x%x, cb=%d\n",
+                   iova, fsynr, cfg->cbndx);
+               ret = IRQ_NONE;
+               resume = RESUME_TERMINATE;
+       }
+
+       /* Clear the faulting FSR */
+       writel(fsr, cb_base + ARM_SMMU_CB_FSR);
+
+       /* Retry or terminate any stalled transactions */
+       if (fsr & FSR_SS)
+               writel_relaxed(resume, cb_base + ARM_SMMU_CB_RESUME);
+
+       return ret;
+}
+
+static irqreturn_t arm_smmu_global_fault(int irq, void *dev)
+{
+       u32 gfsr, gfsynr0, gfsynr1, gfsynr2;
+       struct arm_smmu_device *smmu = dev;
+       void __iomem *gr0_base = ARM_SMMU_GR0_NS(smmu);
+
+       gfsr = readl_relaxed(gr0_base + ARM_SMMU_GR0_sGFSR);
+       gfsynr0 = readl_relaxed(gr0_base + ARM_SMMU_GR0_sGFSYNR0);
+       gfsynr1 = readl_relaxed(gr0_base + ARM_SMMU_GR0_sGFSYNR1);
+       gfsynr2 = readl_relaxed(gr0_base + ARM_SMMU_GR0_sGFSYNR2);
+
+       if (!gfsr)
+               return IRQ_NONE;
+
+       dev_err_ratelimited(smmu->dev,
+               "Unexpected global fault, this could be serious\n");
+       dev_err_ratelimited(smmu->dev,
+               "\tGFSR 0x%08x, GFSYNR0 0x%08x, GFSYNR1 0x%08x, GFSYNR2 0x%08x\n",
+               gfsr, gfsynr0, gfsynr1, gfsynr2);
+
+       writel(gfsr, gr0_base + ARM_SMMU_GR0_sGFSR);
+       return IRQ_HANDLED;
+}
+
+static void arm_smmu_init_context_bank(struct arm_smmu_domain *smmu_domain,
+                                      struct io_pgtable_cfg *pgtbl_cfg)
+{
+       u32 reg;
+       bool stage1;
+       struct arm_smmu_cfg *cfg = &smmu_domain->cfg;
+       struct arm_smmu_device *smmu = smmu_domain->smmu;
+       void __iomem *cb_base, *gr0_base, *gr1_base;
+
+       gr0_base = ARM_SMMU_GR0(smmu);
+       gr1_base = ARM_SMMU_GR1(smmu);
+       stage1 = cfg->cbar != CBAR_TYPE_S2_TRANS;
+       cb_base = ARM_SMMU_CB_BASE(smmu) + ARM_SMMU_CB(smmu, cfg->cbndx);
+
+       if (smmu->version > ARM_SMMU_V1) {
+               /*
+                * CBA2R.
+                * *Must* be initialised before CBAR thanks to VMID16
+                * architectural oversight affected some implementations.
+                */
+#ifdef CONFIG_64BIT
+               reg = CBA2R_RW64_64BIT;
+#else
+               reg = CBA2R_RW64_32BIT;
+#endif
+               writel_relaxed(reg, gr1_base + ARM_SMMU_GR1_CBA2R(cfg->cbndx));
+       }
+
+       /* CBAR */
+       reg = cfg->cbar;
+       if (smmu->version == ARM_SMMU_V1)
+               reg |= cfg->irptndx << CBAR_IRPTNDX_SHIFT;
+
+       /*
+        * Use the weakest shareability/memory types, so they are
+        * overridden by the ttbcr/pte.
+        */
+       if (stage1) {
+               reg |= (CBAR_S1_BPSHCFG_NSH << CBAR_S1_BPSHCFG_SHIFT) |
+                       (CBAR_S1_MEMATTR_WB << CBAR_S1_MEMATTR_SHIFT);
+       } else {
+               reg |= ARM_SMMU_CB_VMID(cfg) << CBAR_VMID_SHIFT;
+       }
+       writel_relaxed(reg, gr1_base + ARM_SMMU_GR1_CBAR(cfg->cbndx));
+
+       /* TTBRs */
+       if (stage1) {
+               reg = pgtbl_cfg->arm_lpae_s1_cfg.ttbr[0];
+               writel_relaxed(reg, cb_base + ARM_SMMU_CB_TTBR0_LO);
+               reg = pgtbl_cfg->arm_lpae_s1_cfg.ttbr[0] >> 32;
+               reg |= ARM_SMMU_CB_ASID(cfg) << TTBRn_HI_ASID_SHIFT;
+               writel_relaxed(reg, cb_base + ARM_SMMU_CB_TTBR0_HI);
+
+               reg = pgtbl_cfg->arm_lpae_s1_cfg.ttbr[1];
+               writel_relaxed(reg, cb_base + ARM_SMMU_CB_TTBR1_LO);
+               reg = pgtbl_cfg->arm_lpae_s1_cfg.ttbr[1] >> 32;
+               reg |= ARM_SMMU_CB_ASID(cfg) << TTBRn_HI_ASID_SHIFT;
+               writel_relaxed(reg, cb_base + ARM_SMMU_CB_TTBR1_HI);
+       } else {
+               reg = pgtbl_cfg->arm_lpae_s2_cfg.vttbr;
+               writel_relaxed(reg, cb_base + ARM_SMMU_CB_TTBR0_LO);
+               reg = pgtbl_cfg->arm_lpae_s2_cfg.vttbr >> 32;
+               writel_relaxed(reg, cb_base + ARM_SMMU_CB_TTBR0_HI);
+       }
+
+       /* TTBCR */
+       if (stage1) {
+               reg = pgtbl_cfg->arm_lpae_s1_cfg.tcr;
+               writel_relaxed(reg, cb_base + ARM_SMMU_CB_TTBCR);
+               if (smmu->version > ARM_SMMU_V1) {
+                       reg = pgtbl_cfg->arm_lpae_s1_cfg.tcr >> 32;
+                       reg |= TTBCR2_SEP_UPSTREAM;
+                       writel_relaxed(reg, cb_base + ARM_SMMU_CB_TTBCR2);
+               }
+       } else {
+               reg = pgtbl_cfg->arm_lpae_s2_cfg.vtcr;
+               writel_relaxed(reg, cb_base + ARM_SMMU_CB_TTBCR);
+       }
+
+       /* MAIRs (stage-1 only) */
+       if (stage1) {
+               reg = pgtbl_cfg->arm_lpae_s1_cfg.mair[0];
+               writel_relaxed(reg, cb_base + ARM_SMMU_CB_S1_MAIR0);
+               reg = pgtbl_cfg->arm_lpae_s1_cfg.mair[1];
+               writel_relaxed(reg, cb_base + ARM_SMMU_CB_S1_MAIR1);
+       }
+
+       /* SCTLR */
+       reg = SCTLR_CFCFG | SCTLR_CFIE | SCTLR_CFRE | SCTLR_M | SCTLR_EAE_SBOP;
+       if (stage1)
+               reg |= SCTLR_S1_ASIDPNE;
+#ifdef __BIG_ENDIAN
+       reg |= SCTLR_E;
+#endif
+       writel_relaxed(reg, cb_base + ARM_SMMU_CB_SCTLR);
+}
+
+static int arm_smmu_init_domain_context(struct iommu_domain *domain,
+                                       struct arm_smmu_device *smmu)
+{
+       int irq, start, ret = 0;
+       unsigned long ias, oas;
+       struct io_pgtable_ops *pgtbl_ops;
+       struct io_pgtable_cfg pgtbl_cfg;
+       enum io_pgtable_fmt fmt;
+       struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+       struct arm_smmu_cfg *cfg = &smmu_domain->cfg;
+
+       mutex_lock(&smmu_domain->init_mutex);
+       if (smmu_domain->smmu)
+               goto out_unlock;
+
+       /*
+        * Mapping the requested stage onto what we support is surprisingly
+        * complicated, mainly because the spec allows S1+S2 SMMUs without
+        * support for nested translation. That means we end up with the
+        * following table:
+        *
+        * Requested        Supported        Actual
+        *     S1               N              S1
+        *     S1             S1+S2            S1
+        *     S1               S2             S2
+        *     S1               S1             S1
+        *     N                N              N
+        *     N              S1+S2            S2
+        *     N                S2             S2
+        *     N                S1             S1
+        *
+        * Note that you can't actually request stage-2 mappings.
+        */
+       if (!(smmu->features & ARM_SMMU_FEAT_TRANS_S1))
+               smmu_domain->stage = ARM_SMMU_DOMAIN_S2;
+       if (!(smmu->features & ARM_SMMU_FEAT_TRANS_S2))
+               smmu_domain->stage = ARM_SMMU_DOMAIN_S1;
+
+       switch (smmu_domain->stage) {
+       case ARM_SMMU_DOMAIN_S1:
+               cfg->cbar = CBAR_TYPE_S1_TRANS_S2_BYPASS;
+               start = smmu->num_s2_context_banks;
+               ias = smmu->va_size;
+               oas = smmu->ipa_size;
+               if (IS_ENABLED(CONFIG_64BIT))
+                       fmt = ARM_64_LPAE_S1;
+               else
+                       fmt = ARM_32_LPAE_S1;
+               break;
+       case ARM_SMMU_DOMAIN_NESTED:
+               /*
+                * We will likely want to change this if/when KVM gets
+                * involved.
+                */
+       case ARM_SMMU_DOMAIN_S2:
+               cfg->cbar = CBAR_TYPE_S2_TRANS;
+               start = 0;
+               ias = smmu->ipa_size;
+               oas = smmu->pa_size;
+               if (IS_ENABLED(CONFIG_64BIT))
+                       fmt = ARM_64_LPAE_S2;
+               else
+                       fmt = ARM_32_LPAE_S2;
+               break;
+       default:
+               ret = -EINVAL;
+               goto out_unlock;
+       }
+
+       ret = __arm_smmu_alloc_bitmap(smmu->context_map, start,
+                                     smmu->num_context_banks);
+       if (IS_ERR_VALUE(ret))
+               goto out_unlock;
+
+       cfg->cbndx = ret;
+       if (smmu->version == ARM_SMMU_V1) {
+               cfg->irptndx = atomic_inc_return(&smmu->irptndx);
+               cfg->irptndx %= smmu->num_context_irqs;
+       } else {
+               cfg->irptndx = cfg->cbndx;
+       }
+
+       pgtbl_cfg = (struct io_pgtable_cfg) {
+               .pgsize_bitmap  = arm_smmu_ops.pgsize_bitmap,
+               .ias            = ias,
+               .oas            = oas,
+               .tlb            = &arm_smmu_gather_ops,
+       };
+
+       smmu_domain->smmu = smmu;
+       pgtbl_ops = alloc_io_pgtable_ops(fmt, &pgtbl_cfg, smmu_domain);
+       if (!pgtbl_ops) {
+               ret = -ENOMEM;
+               goto out_clear_smmu;
+       }
+
+       /* Update our support page sizes to reflect the page table format */
+       arm_smmu_ops.pgsize_bitmap = pgtbl_cfg.pgsize_bitmap;
+
+       /* Initialise the context bank with our page table cfg */
+       arm_smmu_init_context_bank(smmu_domain, &pgtbl_cfg);
+
+       /*
+        * Request context fault interrupt. Do this last to avoid the
+        * handler seeing a half-initialised domain state.
+        */
+       irq = smmu->irqs[smmu->num_global_irqs + cfg->irptndx];
+       ret = request_irq(irq, arm_smmu_context_fault, IRQF_SHARED,
+                         "arm-smmu-context-fault", domain);
+       if (IS_ERR_VALUE(ret)) {
+               dev_err(smmu->dev, "failed to request context IRQ %d (%u)\n",
+                       cfg->irptndx, irq);
+               cfg->irptndx = INVALID_IRPTNDX;
+       }
+
+       mutex_unlock(&smmu_domain->init_mutex);
+
+       /* Publish page table ops for map/unmap */
+       smmu_domain->pgtbl_ops = pgtbl_ops;
+       return 0;
+
+out_clear_smmu:
+       smmu_domain->smmu = NULL;
+out_unlock:
+       mutex_unlock(&smmu_domain->init_mutex);
+       return ret;
+}
+
+static void arm_smmu_destroy_domain_context(struct iommu_domain *domain)
+{
+       struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+       struct arm_smmu_device *smmu = smmu_domain->smmu;
+       struct arm_smmu_cfg *cfg = &smmu_domain->cfg;
+       void __iomem *cb_base;
+       int irq;
+
+       if (!smmu)
+               return;
+
+       /*
+        * Disable the context bank and free the page tables before freeing
+        * it.
+        */
+       cb_base = ARM_SMMU_CB_BASE(smmu) + ARM_SMMU_CB(smmu, cfg->cbndx);
+       writel_relaxed(0, cb_base + ARM_SMMU_CB_SCTLR);
+
+       if (cfg->irptndx != INVALID_IRPTNDX) {
+               irq = smmu->irqs[smmu->num_global_irqs + cfg->irptndx];
+               free_irq(irq, domain);
+       }
+
+       if (smmu_domain->pgtbl_ops)
+               free_io_pgtable_ops(smmu_domain->pgtbl_ops);
+
+       __arm_smmu_free_bitmap(smmu->context_map, cfg->cbndx);
+}
+
+static struct iommu_domain *arm_smmu_domain_alloc(unsigned type)
+{
+       struct arm_smmu_domain *smmu_domain;
+
+       if (type != IOMMU_DOMAIN_UNMANAGED)
+               return NULL;
+       /*
+        * Allocate the domain and initialise some of its data structures.
+        * We can't really do anything meaningful until we've added a
+        * master.
+        */
+       smmu_domain = kzalloc(sizeof(*smmu_domain), GFP_KERNEL);
+       if (!smmu_domain)
+               return NULL;
+
+       mutex_init(&smmu_domain->init_mutex);
+       spin_lock_init(&smmu_domain->pgtbl_lock);
+
+       return &smmu_domain->domain;
+}
+
+static void arm_smmu_domain_free(struct iommu_domain *domain)
+{
+       struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+
+       /*
+        * Free the domain resources. We assume that all devices have
+        * already been detached.
+        */
+       arm_smmu_destroy_domain_context(domain);
+       kfree(smmu_domain);
+}
+
+static int arm_smmu_master_configure_smrs(struct arm_smmu_device *smmu,
+                                         struct arm_smmu_master_cfg *cfg)
+{
+       int i;
+       struct arm_smmu_smr *smrs;
+       void __iomem *gr0_base = ARM_SMMU_GR0(smmu);
+
+       if (!(smmu->features & ARM_SMMU_FEAT_STREAM_MATCH))
+               return 0;
+
+       if (cfg->smrs)
+               return -EEXIST;
+
+       smrs = kmalloc_array(cfg->num_streamids, sizeof(*smrs), GFP_KERNEL);
+       if (!smrs) {
+               dev_err(smmu->dev, "failed to allocate %d SMRs\n",
+                       cfg->num_streamids);
+               return -ENOMEM;
+       }
+
+       /* Allocate the SMRs on the SMMU */
+       for (i = 0; i < cfg->num_streamids; ++i) {
+               int idx = __arm_smmu_alloc_bitmap(smmu->smr_map, 0,
+                                                 smmu->num_mapping_groups);
+               if (IS_ERR_VALUE(idx)) {
+                       dev_err(smmu->dev, "failed to allocate free SMR\n");
+                       goto err_free_smrs;
+               }
+
+               smrs[i] = (struct arm_smmu_smr) {
+                       .idx    = idx,
+                       .mask   = 0, /* We don't currently share SMRs */
+                       .id     = cfg->streamids[i],
+               };
+       }
+
+       /* It worked! Now, poke the actual hardware */
+       for (i = 0; i < cfg->num_streamids; ++i) {
+               u32 reg = SMR_VALID | smrs[i].id << SMR_ID_SHIFT |
+                         smrs[i].mask << SMR_MASK_SHIFT;
+               writel_relaxed(reg, gr0_base + ARM_SMMU_GR0_SMR(smrs[i].idx));
+       }
+
+       cfg->smrs = smrs;
+       return 0;
+
+err_free_smrs:
+       while (--i >= 0)
+               __arm_smmu_free_bitmap(smmu->smr_map, smrs[i].idx);
+       kfree(smrs);
+       return -ENOSPC;
+}
+
+static void arm_smmu_master_free_smrs(struct arm_smmu_device *smmu,
+                                     struct arm_smmu_master_cfg *cfg)
+{
+       int i;
+       void __iomem *gr0_base = ARM_SMMU_GR0(smmu);
+       struct arm_smmu_smr *smrs = cfg->smrs;
+
+       if (!smrs)
+               return;
+
+       /* Invalidate the SMRs before freeing back to the allocator */
+       for (i = 0; i < cfg->num_streamids; ++i) {
+               u8 idx = smrs[i].idx;
+
+               writel_relaxed(~SMR_VALID, gr0_base + ARM_SMMU_GR0_SMR(idx));
+               __arm_smmu_free_bitmap(smmu->smr_map, idx);
+       }
+
+       cfg->smrs = NULL;
+       kfree(smrs);
+}
+
+static int arm_smmu_domain_add_master(struct arm_smmu_domain *smmu_domain,
+                                     struct arm_smmu_master_cfg *cfg)
+{
+       int i, ret;
+       struct arm_smmu_device *smmu = smmu_domain->smmu;
+       void __iomem *gr0_base = ARM_SMMU_GR0(smmu);
+
+       /* Devices in an IOMMU group may already be configured */
+       ret = arm_smmu_master_configure_smrs(smmu, cfg);
+       if (ret)
+               return ret == -EEXIST ? 0 : ret;
+
+       for (i = 0; i < cfg->num_streamids; ++i) {
+               u32 idx, s2cr;
+
+               idx = cfg->smrs ? cfg->smrs[i].idx : cfg->streamids[i];
+               s2cr = S2CR_TYPE_TRANS |
+                      (smmu_domain->cfg.cbndx << S2CR_CBNDX_SHIFT);
+               writel_relaxed(s2cr, gr0_base + ARM_SMMU_GR0_S2CR(idx));
+       }
+
+       return 0;
+}
+
+static void arm_smmu_domain_remove_master(struct arm_smmu_domain *smmu_domain,
+                                         struct arm_smmu_master_cfg *cfg)
+{
+       int i;
+       struct arm_smmu_device *smmu = smmu_domain->smmu;
+       void __iomem *gr0_base = ARM_SMMU_GR0(smmu);
+
+       /* An IOMMU group is torn down by the first device to be removed */
+       if ((smmu->features & ARM_SMMU_FEAT_STREAM_MATCH) && !cfg->smrs)
+               return;
+
+       /*
+        * We *must* clear the S2CR first, because freeing the SMR means
+        * that it can be re-allocated immediately.
+        */
+       for (i = 0; i < cfg->num_streamids; ++i) {
+               u32 idx = cfg->smrs ? cfg->smrs[i].idx : cfg->streamids[i];
+
+               writel_relaxed(S2CR_TYPE_BYPASS,
+                              gr0_base + ARM_SMMU_GR0_S2CR(idx));
+       }
+
+       arm_smmu_master_free_smrs(smmu, cfg);
+}
+
+static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
+{
+       int ret;
+       struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+       struct arm_smmu_device *smmu;
+       struct arm_smmu_master_cfg *cfg;
+
+       smmu = find_smmu_for_device(dev);
+       if (!smmu) {
+               dev_err(dev, "cannot attach to SMMU, is it on the same bus?\n");
+               return -ENXIO;
+       }
+
+       if (dev->archdata.iommu) {
+               dev_err(dev, "already attached to IOMMU domain\n");
+               return -EEXIST;
+       }
+
+       /* Ensure that the domain is finalised */
+       ret = arm_smmu_init_domain_context(domain, smmu);
+       if (IS_ERR_VALUE(ret))
+               return ret;
+
+       /*
+        * Sanity check the domain. We don't support domains across
+        * different SMMUs.
+        */
+       if (smmu_domain->smmu != smmu) {
+               dev_err(dev,
+                       "cannot attach to SMMU %s whilst already attached to domain on SMMU %s\n",
+                       dev_name(smmu_domain->smmu->dev), dev_name(smmu->dev));
+               return -EINVAL;
+       }
+
+       /* Looks ok, so add the device to the domain */
+       cfg = find_smmu_master_cfg(dev);
+       if (!cfg)
+               return -ENODEV;
+
+       ret = arm_smmu_domain_add_master(smmu_domain, cfg);
+       if (!ret)
+               dev->archdata.iommu = domain;
+       return ret;
+}
+
+static void arm_smmu_detach_dev(struct iommu_domain *domain, struct device *dev)
+{
+       struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+       struct arm_smmu_master_cfg *cfg;
+
+       cfg = find_smmu_master_cfg(dev);
+       if (!cfg)
+               return;
+
+       dev->archdata.iommu = NULL;
+       arm_smmu_domain_remove_master(smmu_domain, cfg);
+}
+
+static int arm_smmu_map(struct iommu_domain *domain, unsigned long iova,
+                       phys_addr_t paddr, size_t size, int prot)
+{
+       int ret;
+       unsigned long flags;
+       struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+       struct io_pgtable_ops *ops= smmu_domain->pgtbl_ops;
+
+       if (!ops)
+               return -ENODEV;
+
+       spin_lock_irqsave(&smmu_domain->pgtbl_lock, flags);
+       ret = ops->map(ops, iova, paddr, size, prot);
+       spin_unlock_irqrestore(&smmu_domain->pgtbl_lock, flags);
+       return ret;
+}
+
+static size_t arm_smmu_unmap(struct iommu_domain *domain, unsigned long iova,
+                            size_t size)
+{
+       size_t ret;
+       unsigned long flags;
+       struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+       struct io_pgtable_ops *ops= smmu_domain->pgtbl_ops;
+
+       if (!ops)
+               return 0;
+
+       spin_lock_irqsave(&smmu_domain->pgtbl_lock, flags);
+       ret = ops->unmap(ops, iova, size);
+       spin_unlock_irqrestore(&smmu_domain->pgtbl_lock, flags);
+       return ret;
+}
+
+static phys_addr_t arm_smmu_iova_to_phys_hard(struct iommu_domain *domain,
+                                             dma_addr_t iova)
+{
+       struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+       struct arm_smmu_device *smmu = smmu_domain->smmu;
+       struct arm_smmu_cfg *cfg = &smmu_domain->cfg;
+       struct io_pgtable_ops *ops= smmu_domain->pgtbl_ops;
+       struct device *dev = smmu->dev;
+       void __iomem *cb_base;
+       u32 tmp;
+       u64 phys;
+
+       cb_base = ARM_SMMU_CB_BASE(smmu) + ARM_SMMU_CB(smmu, cfg->cbndx);
+
+       if (smmu->version == 1) {
+               u32 reg = iova & ~0xfff;
+               writel_relaxed(reg, cb_base + ARM_SMMU_CB_ATS1PR_LO);
+       } else {
+               u32 reg = iova & ~0xfff;
+               writel_relaxed(reg, cb_base + ARM_SMMU_CB_ATS1PR_LO);
+               reg = ((u64)iova & ~0xfff) >> 32;
+               writel_relaxed(reg, cb_base + ARM_SMMU_CB_ATS1PR_HI);
+       }
+
+       if (readl_poll_timeout_atomic(cb_base + ARM_SMMU_CB_ATSR, tmp,
+                                     !(tmp & ATSR_ACTIVE), 5, 50)) {
+               dev_err(dev,
+                       "iova to phys timed out on 0x%pad. Falling back to software table walk.\n",
+                       &iova);
+               return ops->iova_to_phys(ops, iova);
+       }
+
+       phys = readl_relaxed(cb_base + ARM_SMMU_CB_PAR_LO);
+       phys |= ((u64)readl_relaxed(cb_base + ARM_SMMU_CB_PAR_HI)) << 32;
+
+       if (phys & CB_PAR_F) {
+               dev_err(dev, "translation fault!\n");
+               dev_err(dev, "PAR = 0x%llx\n", phys);
+               return 0;
+       }
+
+       return (phys & GENMASK_ULL(39, 12)) | (iova & 0xfff);
+}
+
+static phys_addr_t arm_smmu_iova_to_phys(struct iommu_domain *domain,
+                                       dma_addr_t iova)
+{
+       phys_addr_t ret;
+       unsigned long flags;
+       struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+       struct io_pgtable_ops *ops= smmu_domain->pgtbl_ops;
+
+       if (!ops)
+               return 0;
+
+       spin_lock_irqsave(&smmu_domain->pgtbl_lock, flags);
+       if (smmu_domain->smmu->features & ARM_SMMU_FEAT_TRANS_OPS &&
+                       smmu_domain->stage == ARM_SMMU_DOMAIN_S1) {
+               ret = arm_smmu_iova_to_phys_hard(domain, iova);
+       } else {
+               ret = ops->iova_to_phys(ops, iova);
+       }
+
+       spin_unlock_irqrestore(&smmu_domain->pgtbl_lock, flags);
+
+       return ret;
+}
+
+static bool arm_smmu_capable(enum iommu_cap cap)
+{
+       switch (cap) {
+       case IOMMU_CAP_CACHE_COHERENCY:
+               /*
+                * Return true here as the SMMU can always send out coherent
+                * requests.
+                */
+               return true;
+       case IOMMU_CAP_INTR_REMAP:
+               return true; /* MSIs are just memory writes */
+       case IOMMU_CAP_NOEXEC:
+               return true;
+       default:
+               return false;
+       }
+}
+
+static int __arm_smmu_get_pci_sid(struct pci_dev *pdev, u16 alias, void *data)
+{
+       *((u16 *)data) = alias;
+       return 0; /* Continue walking */
+}
+
+static void __arm_smmu_release_pci_iommudata(void *data)
+{
+       kfree(data);
+}
+
+static int arm_smmu_add_pci_device(struct pci_dev *pdev)
+{
+       int i, ret;
+       u16 sid;
+       struct iommu_group *group;
+       struct arm_smmu_master_cfg *cfg;
+
+       group = iommu_group_get_for_dev(&pdev->dev);
+       if (IS_ERR(group))
+               return PTR_ERR(group);
+
+       cfg = iommu_group_get_iommudata(group);
+       if (!cfg) {
+               cfg = kzalloc(sizeof(*cfg), GFP_KERNEL);
+               if (!cfg) {
+                       ret = -ENOMEM;
+                       goto out_put_group;
+               }
+
+               iommu_group_set_iommudata(group, cfg,
+                                         __arm_smmu_release_pci_iommudata);
+       }
+
+       if (cfg->num_streamids >= MAX_MASTER_STREAMIDS) {
+               ret = -ENOSPC;
+               goto out_put_group;
+       }
+
+       /*
+        * Assume Stream ID == Requester ID for now.
+        * We need a way to describe the ID mappings in FDT.
+        */
+       pci_for_each_dma_alias(pdev, __arm_smmu_get_pci_sid, &sid);
+       for (i = 0; i < cfg->num_streamids; ++i)
+               if (cfg->streamids[i] == sid)
+                       break;
+
+       /* Avoid duplicate SIDs, as this can lead to SMR conflicts */
+       if (i == cfg->num_streamids)
+               cfg->streamids[cfg->num_streamids++] = sid;
+
+       return 0;
+out_put_group:
+       iommu_group_put(group);
+       return ret;
+}
+
+static int arm_smmu_add_platform_device(struct device *dev)
+{
+       struct iommu_group *group;
+       struct arm_smmu_master *master;
+       struct arm_smmu_device *smmu = find_smmu_for_device(dev);
+
+       if (!smmu)
+               return -ENODEV;
+
+       master = find_smmu_master(smmu, dev->of_node);
+       if (!master)
+               return -ENODEV;
+
+       /* No automatic group creation for platform devices */
+       group = iommu_group_alloc();
+       if (IS_ERR(group))
+               return PTR_ERR(group);
+
+       iommu_group_set_iommudata(group, &master->cfg, NULL);
+       return iommu_group_add_device(group, dev);
+}
+
+static int arm_smmu_add_device(struct device *dev)
+{
+       if (dev_is_pci(dev))
+               return arm_smmu_add_pci_device(to_pci_dev(dev));
+
+       return arm_smmu_add_platform_device(dev);
+}
+
+static void arm_smmu_remove_device(struct device *dev)
+{
+       iommu_group_remove_device(dev);
+}
+
+static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
+                                   enum iommu_attr attr, void *data)
+{
+       struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+
+       switch (attr) {
+       case DOMAIN_ATTR_NESTING:
+               *(int *)data = (smmu_domain->stage == ARM_SMMU_DOMAIN_NESTED);
+               return 0;
+       default:
+               return -ENODEV;
+       }
+}
+
+static int arm_smmu_domain_set_attr(struct iommu_domain *domain,
+                                   enum iommu_attr attr, void *data)
+{
+       int ret = 0;
+       struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+
+       mutex_lock(&smmu_domain->init_mutex);
+
+       switch (attr) {
+       case DOMAIN_ATTR_NESTING:
+               if (smmu_domain->smmu) {
+                       ret = -EPERM;
+                       goto out_unlock;
+               }
+
+               if (*(int *)data)
+                       smmu_domain->stage = ARM_SMMU_DOMAIN_NESTED;
+               else
+                       smmu_domain->stage = ARM_SMMU_DOMAIN_S1;
+
+               break;
+       default:
+               ret = -ENODEV;
+       }
+
+out_unlock:
+       mutex_unlock(&smmu_domain->init_mutex);
+       return ret;
+}
+
+static struct iommu_ops arm_smmu_ops = {
+       .capable                = arm_smmu_capable,
+       .domain_alloc           = arm_smmu_domain_alloc,
+       .domain_free            = arm_smmu_domain_free,
+       .attach_dev             = arm_smmu_attach_dev,
+       .detach_dev             = arm_smmu_detach_dev,
+       .map                    = arm_smmu_map,
+       .unmap                  = arm_smmu_unmap,
+       .map_sg                 = default_iommu_map_sg,
+       .iova_to_phys           = arm_smmu_iova_to_phys,
+       .add_device             = arm_smmu_add_device,
+       .remove_device          = arm_smmu_remove_device,
+       .domain_get_attr        = arm_smmu_domain_get_attr,
+       .domain_set_attr        = arm_smmu_domain_set_attr,
+       .pgsize_bitmap          = -1UL, /* Restricted during device attach */
+};
+
+static void arm_smmu_device_reset(struct arm_smmu_device *smmu)
+{
+       void __iomem *gr0_base = ARM_SMMU_GR0(smmu);
+       void __iomem *cb_base;
+       int i = 0;
+       u32 reg;
+
+       /* clear global FSR */
+       reg = readl_relaxed(ARM_SMMU_GR0_NS(smmu) + ARM_SMMU_GR0_sGFSR);
+       writel(reg, ARM_SMMU_GR0_NS(smmu) + ARM_SMMU_GR0_sGFSR);
+
+       /* Mark all SMRn as invalid and all S2CRn as bypass */
+       for (i = 0; i < smmu->num_mapping_groups; ++i) {
+               writel_relaxed(0, gr0_base + ARM_SMMU_GR0_SMR(i));
+               writel_relaxed(S2CR_TYPE_BYPASS,
+                       gr0_base + ARM_SMMU_GR0_S2CR(i));
+       }
+
+       /* Make sure all context banks are disabled and clear CB_FSR  */
+       for (i = 0; i < smmu->num_context_banks; ++i) {
+               cb_base = ARM_SMMU_CB_BASE(smmu) + ARM_SMMU_CB(smmu, i);
+               writel_relaxed(0, cb_base + ARM_SMMU_CB_SCTLR);
+               writel_relaxed(FSR_FAULT, cb_base + ARM_SMMU_CB_FSR);
+       }
+
+       /* Invalidate the TLB, just in case */
+       writel_relaxed(0, gr0_base + ARM_SMMU_GR0_TLBIALLH);
+       writel_relaxed(0, gr0_base + ARM_SMMU_GR0_TLBIALLNSNH);
+
+       reg = readl_relaxed(ARM_SMMU_GR0_NS(smmu) + ARM_SMMU_GR0_sCR0);
+
+       /* Enable fault reporting */
+       reg |= (sCR0_GFRE | sCR0_GFIE | sCR0_GCFGFRE | sCR0_GCFGFIE);
+
+       /* Disable TLB broadcasting. */
+       reg |= (sCR0_VMIDPNE | sCR0_PTM);
+
+       /* Enable client access, but bypass when no mapping is found */
+       reg &= ~(sCR0_CLIENTPD | sCR0_USFCFG);
+
+       /* Disable forced broadcasting */
+       reg &= ~sCR0_FB;
+
+       /* Don't upgrade barriers */
+       reg &= ~(sCR0_BSU_MASK << sCR0_BSU_SHIFT);
+
+       /* Push the button */
+       __arm_smmu_tlb_sync(smmu);
+       writel(reg, ARM_SMMU_GR0_NS(smmu) + ARM_SMMU_GR0_sCR0);
+}
+
+static int arm_smmu_id_size_to_bits(int size)
+{
+       switch (size) {
+       case 0:
+               return 32;
+       case 1:
+               return 36;
+       case 2:
+               return 40;
+       case 3:
+               return 42;
+       case 4:
+               return 44;
+       case 5:
+       default:
+               return 48;
+       }
+}
+
+static int arm_smmu_device_cfg_probe(struct arm_smmu_device *smmu)
+{
+       unsigned long size;
+       void __iomem *gr0_base = ARM_SMMU_GR0(smmu);
+       u32 id;
+
+       dev_notice(smmu->dev, "probing hardware configuration...\n");
+       dev_notice(smmu->dev, "SMMUv%d with:\n", smmu->version);
+
+       /* ID0 */
+       id = readl_relaxed(gr0_base + ARM_SMMU_GR0_ID0);
+
+       /* Restrict available stages based on module parameter */
+       if (force_stage == 1)
+               id &= ~(ID0_S2TS | ID0_NTS);
+       else if (force_stage == 2)
+               id &= ~(ID0_S1TS | ID0_NTS);
+
+       if (id & ID0_S1TS) {
+               smmu->features |= ARM_SMMU_FEAT_TRANS_S1;
+               dev_notice(smmu->dev, "\tstage 1 translation\n");
+       }
+
+       if (id & ID0_S2TS) {
+               smmu->features |= ARM_SMMU_FEAT_TRANS_S2;
+               dev_notice(smmu->dev, "\tstage 2 translation\n");
+       }
+
+       if (id & ID0_NTS) {
+               smmu->features |= ARM_SMMU_FEAT_TRANS_NESTED;
+               dev_notice(smmu->dev, "\tnested translation\n");
+       }
+
+       if (!(smmu->features &
+               (ARM_SMMU_FEAT_TRANS_S1 | ARM_SMMU_FEAT_TRANS_S2))) {
+               dev_err(smmu->dev, "\tno translation support!\n");
+               return -ENODEV;
+       }
+
+       if ((id & ID0_S1TS) && ((smmu->version == 1) || !(id & ID0_ATOSNS))) {
+               smmu->features |= ARM_SMMU_FEAT_TRANS_OPS;
+               dev_notice(smmu->dev, "\taddress translation ops\n");
+       }
+
+       if (id & ID0_CTTW) {
+               smmu->features |= ARM_SMMU_FEAT_COHERENT_WALK;
+               dev_notice(smmu->dev, "\tcoherent table walk\n");
+       }
+
+       if (id & ID0_SMS) {
+               u32 smr, sid, mask;
+
+               smmu->features |= ARM_SMMU_FEAT_STREAM_MATCH;
+               smmu->num_mapping_groups = (id >> ID0_NUMSMRG_SHIFT) &
+                                          ID0_NUMSMRG_MASK;
+               if (smmu->num_mapping_groups == 0) {
+                       dev_err(smmu->dev,
+                               "stream-matching supported, but no SMRs present!\n");
+                       return -ENODEV;
+               }
+
+               smr = SMR_MASK_MASK << SMR_MASK_SHIFT;
+               smr |= (SMR_ID_MASK << SMR_ID_SHIFT);
+               writel_relaxed(smr, gr0_base + ARM_SMMU_GR0_SMR(0));
+               smr = readl_relaxed(gr0_base + ARM_SMMU_GR0_SMR(0));
+
+               mask = (smr >> SMR_MASK_SHIFT) & SMR_MASK_MASK;
+               sid = (smr >> SMR_ID_SHIFT) & SMR_ID_MASK;
+               if ((mask & sid) != sid) {
+                       dev_err(smmu->dev,
+                               "SMR mask bits (0x%x) insufficient for ID field (0x%x)\n",
+                               mask, sid);
+                       return -ENODEV;
+               }
+
+               dev_notice(smmu->dev,
+                          "\tstream matching with %u register groups, mask 0x%x",
+                          smmu->num_mapping_groups, mask);
+       } else {
+               smmu->num_mapping_groups = (id >> ID0_NUMSIDB_SHIFT) &
+                                          ID0_NUMSIDB_MASK;
+       }
+
+       /* ID1 */
+       id = readl_relaxed(gr0_base + ARM_SMMU_GR0_ID1);
+       smmu->pgshift = (id & ID1_PAGESIZE) ? 16 : 12;
+
+       /* Check for size mismatch of SMMU address space from mapped region */
+       size = 1 << (((id >> ID1_NUMPAGENDXB_SHIFT) & ID1_NUMPAGENDXB_MASK) + 1);
+       size *= 2 << smmu->pgshift;
+       if (smmu->size != size)
+               dev_warn(smmu->dev,
+                       "SMMU address space size (0x%lx) differs from mapped region size (0x%lx)!\n",
+                       size, smmu->size);
+
+       smmu->num_s2_context_banks = (id >> ID1_NUMS2CB_SHIFT) & ID1_NUMS2CB_MASK;
+       smmu->num_context_banks = (id >> ID1_NUMCB_SHIFT) & ID1_NUMCB_MASK;
+       if (smmu->num_s2_context_banks > smmu->num_context_banks) {
+               dev_err(smmu->dev, "impossible number of S2 context banks!\n");
+               return -ENODEV;
+       }
+       dev_notice(smmu->dev, "\t%u context banks (%u stage-2 only)\n",
+                  smmu->num_context_banks, smmu->num_s2_context_banks);
+
+       /* ID2 */
+       id = readl_relaxed(gr0_base + ARM_SMMU_GR0_ID2);
+       size = arm_smmu_id_size_to_bits((id >> ID2_IAS_SHIFT) & ID2_IAS_MASK);
+       smmu->ipa_size = size;
+
+       /* The output mask is also applied for bypass */
+       size = arm_smmu_id_size_to_bits((id >> ID2_OAS_SHIFT) & ID2_OAS_MASK);
+       smmu->pa_size = size;
+
+       /*
+        * What the page table walker can address actually depends on which
+        * descriptor format is in use, but since a) we don't know that yet,
+        * and b) it can vary per context bank, this will have to do...
+        */
+       if (dma_set_mask_and_coherent(smmu->dev, DMA_BIT_MASK(size)))
+               dev_warn(smmu->dev,
+                        "failed to set DMA mask for table walker\n");
+
+       if (smmu->version == ARM_SMMU_V1) {
+               smmu->va_size = smmu->ipa_size;
+               size = SZ_4K | SZ_2M | SZ_1G;
+       } else {
+               size = (id >> ID2_UBS_SHIFT) & ID2_UBS_MASK;
+               smmu->va_size = arm_smmu_id_size_to_bits(size);
+#ifndef CONFIG_64BIT
+               smmu->va_size = min(32UL, smmu->va_size);
+#endif
+               size = 0;
+               if (id & ID2_PTFS_4K)
+                       size |= SZ_4K | SZ_2M | SZ_1G;
+               if (id & ID2_PTFS_16K)
+                       size |= SZ_16K | SZ_32M;
+               if (id & ID2_PTFS_64K)
+                       size |= SZ_64K | SZ_512M;
+       }
+
+       arm_smmu_ops.pgsize_bitmap &= size;
+       dev_notice(smmu->dev, "\tSupported page sizes: 0x%08lx\n", size);
+
+       if (smmu->features & ARM_SMMU_FEAT_TRANS_S1)
+               dev_notice(smmu->dev, "\tStage-1: %lu-bit VA -> %lu-bit IPA\n",
+                          smmu->va_size, smmu->ipa_size);
+
+       if (smmu->features & ARM_SMMU_FEAT_TRANS_S2)
+               dev_notice(smmu->dev, "\tStage-2: %lu-bit IPA -> %lu-bit PA\n",
+                          smmu->ipa_size, smmu->pa_size);
+
+       return 0;
+}
+
+static const struct of_device_id arm_smmu_of_match[] = {
+       { .compatible = "arm,smmu-v1", .data = (void *)ARM_SMMU_V1 },
+       { .compatible = "arm,smmu-v2", .data = (void *)ARM_SMMU_V2 },
+       { .compatible = "arm,mmu-400", .data = (void *)ARM_SMMU_V1 },
+       { .compatible = "arm,mmu-401", .data = (void *)ARM_SMMU_V1 },
+       { .compatible = "arm,mmu-500", .data = (void *)ARM_SMMU_V2 },
+       { },
+};
+MODULE_DEVICE_TABLE(of, arm_smmu_of_match);
+
+static int arm_smmu_device_dt_probe(struct platform_device *pdev)
+{
+       const struct of_device_id *of_id;
+       struct resource *res;
+       struct arm_smmu_device *smmu;
+       struct device *dev = &pdev->dev;
+       struct rb_node *node;
+       struct of_phandle_args masterspec;
+       int num_irqs, i, err;
+
+       smmu = devm_kzalloc(dev, sizeof(*smmu), GFP_KERNEL);
+       if (!smmu) {
+               dev_err(dev, "failed to allocate arm_smmu_device\n");
+               return -ENOMEM;
+       }
+       smmu->dev = dev;
+
+       of_id = of_match_node(arm_smmu_of_match, dev->of_node);
+       smmu->version = (enum arm_smmu_arch_version)of_id->data;
+
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       smmu->base = devm_ioremap_resource(dev, res);
+       if (IS_ERR(smmu->base))
+               return PTR_ERR(smmu->base);
+       smmu->size = resource_size(res);
+
+       if (of_property_read_u32(dev->of_node, "#global-interrupts",
+                                &smmu->num_global_irqs)) {
+               dev_err(dev, "missing #global-interrupts property\n");
+               return -ENODEV;
+       }
+
+       num_irqs = 0;
+       while ((res = platform_get_resource(pdev, IORESOURCE_IRQ, num_irqs))) {
+               num_irqs++;
+               if (num_irqs > smmu->num_global_irqs)
+                       smmu->num_context_irqs++;
+       }
+
+       if (!smmu->num_context_irqs) {
+               dev_err(dev, "found %d interrupts but expected at least %d\n",
+                       num_irqs, smmu->num_global_irqs + 1);
+               return -ENODEV;
+       }
+
+       smmu->irqs = devm_kzalloc(dev, sizeof(*smmu->irqs) * num_irqs,
+                                 GFP_KERNEL);
+       if (!smmu->irqs) {
+               dev_err(dev, "failed to allocate %d irqs\n", num_irqs);
+               return -ENOMEM;
+       }
+
+       for (i = 0; i < num_irqs; ++i) {
+               int irq = platform_get_irq(pdev, i);
+
+               if (irq < 0) {
+                       dev_err(dev, "failed to get irq index %d\n", i);
+                       return -ENODEV;
+               }
+               smmu->irqs[i] = irq;
+       }
+
+       err = arm_smmu_device_cfg_probe(smmu);
+       if (err)
+               return err;
+
+       i = 0;
+       smmu->masters = RB_ROOT;
+       while (!of_parse_phandle_with_args(dev->of_node, "mmu-masters",
+                                          "#stream-id-cells", i,
+                                          &masterspec)) {
+               err = register_smmu_master(smmu, dev, &masterspec);
+               if (err) {
+                       dev_err(dev, "failed to add master %s\n",
+                               masterspec.np->name);
+                       goto out_put_masters;
+               }
+
+               i++;
+       }
+       dev_notice(dev, "registered %d master devices\n", i);
+
+       parse_driver_options(smmu);
+
+       if (smmu->version > ARM_SMMU_V1 &&
+           smmu->num_context_banks != smmu->num_context_irqs) {
+               dev_err(dev,
+                       "found only %d context interrupt(s) but %d required\n",
+                       smmu->num_context_irqs, smmu->num_context_banks);
+               err = -ENODEV;
+               goto out_put_masters;
+       }
+
+       for (i = 0; i < smmu->num_global_irqs; ++i) {
+               err = request_irq(smmu->irqs[i],
+                                 arm_smmu_global_fault,
+                                 IRQF_SHARED,
+                                 "arm-smmu global fault",
+                                 smmu);
+               if (err) {
+                       dev_err(dev, "failed to request global IRQ %d (%u)\n",
+                               i, smmu->irqs[i]);
+                       goto out_free_irqs;
+               }
+       }
+
+       INIT_LIST_HEAD(&smmu->list);
+       spin_lock(&arm_smmu_devices_lock);
+       list_add(&smmu->list, &arm_smmu_devices);
+       spin_unlock(&arm_smmu_devices_lock);
+
+       arm_smmu_device_reset(smmu);
+       return 0;
+
+out_free_irqs:
+       while (i--)
+               free_irq(smmu->irqs[i], smmu);
+
+out_put_masters:
+       for (node = rb_first(&smmu->masters); node; node = rb_next(node)) {
+               struct arm_smmu_master *master
+                       = container_of(node, struct arm_smmu_master, node);
+               of_node_put(master->of_node);
+       }
+
+       return err;
+}
+
+static int arm_smmu_device_remove(struct platform_device *pdev)
+{
+       int i;
+       struct device *dev = &pdev->dev;
+       struct arm_smmu_device *curr, *smmu = NULL;
+       struct rb_node *node;
+
+       spin_lock(&arm_smmu_devices_lock);
+       list_for_each_entry(curr, &arm_smmu_devices, list) {
+               if (curr->dev == dev) {
+                       smmu = curr;
+                       list_del(&smmu->list);
+                       break;
+               }
+       }
+       spin_unlock(&arm_smmu_devices_lock);
+
+       if (!smmu)
+               return -ENODEV;
+
+       for (node = rb_first(&smmu->masters); node; node = rb_next(node)) {
+               struct arm_smmu_master *master
+                       = container_of(node, struct arm_smmu_master, node);
+               of_node_put(master->of_node);
+       }
+
+       if (!bitmap_empty(smmu->context_map, ARM_SMMU_MAX_CBS))
+               dev_err(dev, "removing device with active domains!\n");
+
+       for (i = 0; i < smmu->num_global_irqs; ++i)
+               free_irq(smmu->irqs[i], smmu);
+
+       /* Turn the thing off */
+       writel(sCR0_CLIENTPD, ARM_SMMU_GR0_NS(smmu) + ARM_SMMU_GR0_sCR0);
+       return 0;
+}
+
+static struct platform_driver arm_smmu_driver = {
+       .driver = {
+               .name           = "arm-smmu",
+               .of_match_table = of_match_ptr(arm_smmu_of_match),
+       },
+       .probe  = arm_smmu_device_dt_probe,
+       .remove = arm_smmu_device_remove,
+};
+
+static int __init arm_smmu_init(void)
+{
+       struct device_node *np;
+       int ret;
+
+       /*
+        * Play nice with systems that don't have an ARM SMMU by checking that
+        * an ARM SMMU exists in the system before proceeding with the driver
+        * and IOMMU bus operation registration.
+        */
+       np = of_find_matching_node(NULL, arm_smmu_of_match);
+       if (!np)
+               return 0;
+
+       of_node_put(np);
+
+       ret = platform_driver_register(&arm_smmu_driver);
+       if (ret)
+               return ret;
+
+       /* Oh, for a proper bus abstraction */
+       if (!iommu_present(&platform_bus_type))
+               bus_set_iommu(&platform_bus_type, &arm_smmu_ops);
+
+#ifdef CONFIG_ARM_AMBA
+       if (!iommu_present(&amba_bustype))
+               bus_set_iommu(&amba_bustype, &arm_smmu_ops);
+#endif
+
+#ifdef CONFIG_PCI
+       if (!iommu_present(&pci_bus_type))
+               bus_set_iommu(&pci_bus_type, &arm_smmu_ops);
+#endif
+
+       return 0;
+}
+
+static void __exit arm_smmu_exit(void)
+{
+       return platform_driver_unregister(&arm_smmu_driver);
+}
+
+subsys_initcall(arm_smmu_init);
+module_exit(arm_smmu_exit);
+
+MODULE_DESCRIPTION("IOMMU API for ARM architected SMMU implementations");
+MODULE_AUTHOR("Will Deacon <will.deacon@arm.com>");
+MODULE_LICENSE("GPL v2");