iommu/arm: Add support for ARM Ltd. System MMU architecture

This patch adds support for SMMUs implementing the ARM System MMU
architecture versions 1 or 2. Both arm and arm64 are supported, although
the v7s descriptor format is not used.

Cc: Rob Herring <robherring2@gmail.com>
Cc: Andreas Herrmann <andreas.herrmann@calxeda.com>
Cc: Olav Haugan <ohaugan@codeaurora.org>
Cc: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Acked-by: Andreas Herrmann <andreas.herrmann@calxeda.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>

1 files changed, 1969 insertions, 0 deletions

diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
new file mode 100644
index 0000000..ebd0a4c
--- /dev/null
+++ b/drivers/iommu/arm-smmu.c
@@ -0,0 +1,1969 @@
+/*
+ * 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
+ *	- 4k and 64k pages, with contiguous pte hints.
+ *	- Up to 39-bit addressing
+ *	- 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/mm.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+#include <linux/amba/bus.h>
+
+#include <asm/pgalloc.h>
+
+/* Maximum number of stream IDs assigned to a single device */
+#define MAX_MASTER_STREAMIDS		8
+
+/* 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
+
+/* Number of VMIDs per SMMU */
+#define ARM_SMMU_NUM_VMIDS		256
+
+/* SMMU global address space */
+#define ARM_SMMU_GR0(smmu)		((smmu)->base)
+#define ARM_SMMU_GR1(smmu)		((smmu)->base + (smmu)->pagesize)
+
+/* Page table bits */
+#define ARM_SMMU_PTE_PAGE		(((pteval_t)3) << 0)
+#define ARM_SMMU_PTE_CONT		(((pteval_t)1) << 52)
+#define ARM_SMMU_PTE_AF			(((pteval_t)1) << 10)
+#define ARM_SMMU_PTE_SH_NS		(((pteval_t)0) << 8)
+#define ARM_SMMU_PTE_SH_OS		(((pteval_t)2) << 8)
+#define ARM_SMMU_PTE_SH_IS		(((pteval_t)3) << 8)
+
+#if PAGE_SIZE == SZ_4K
+#define ARM_SMMU_PTE_CONT_ENTRIES	16
+#elif PAGE_SIZE == SZ_64K
+#define ARM_SMMU_PTE_CONT_ENTRIES	32
+#else
+#define ARM_SMMU_PTE_CONT_ENTRIES	1
+#endif
+
+#define ARM_SMMU_PTE_CONT_SIZE		(PAGE_SIZE * ARM_SMMU_PTE_CONT_ENTRIES)
+#define ARM_SMMU_PTE_CONT_MASK		(~(ARM_SMMU_PTE_CONT_SIZE - 1))
+#define ARM_SMMU_PTE_HWTABLE_SIZE	(PTRS_PER_PTE * sizeof(pte_t))
+
+/* Stage-1 PTE */
+#define ARM_SMMU_PTE_AP_UNPRIV		(((pteval_t)1) << 6)
+#define ARM_SMMU_PTE_AP_RDONLY		(((pteval_t)2) << 6)
+#define ARM_SMMU_PTE_ATTRINDX_SHIFT	2
+
+/* Stage-2 PTE */
+#define ARM_SMMU_PTE_HAP_FAULT		(((pteval_t)0) << 6)
+#define ARM_SMMU_PTE_HAP_READ		(((pteval_t)1) << 6)
+#define ARM_SMMU_PTE_HAP_WRITE		(((pteval_t)2) << 6)
+#define ARM_SMMU_PTE_MEMATTR_OIWB	(((pteval_t)0xf) << 2)
+#define ARM_SMMU_PTE_MEMATTR_NC		(((pteval_t)0x5) << 2)
+#define ARM_SMMU_PTE_MEMATTR_DEV	(((pteval_t)0x1) << 2)
+
+/* 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 ARM_SMMU_GR0_PIDR0		0xfe0
+#define ARM_SMMU_GR0_PIDR1		0xfe4
+#define ARM_SMMU_GR0_PIDR2		0xfe8
+
+#define ID0_S1TS			(1 << 30)
+#define ID0_S2TS			(1 << 29)
+#define ID0_NTS				(1 << 28)
+#define ID0_SMS				(1 << 27)
+#define ID0_PTFS_SHIFT			24
+#define ID0_PTFS_MASK			0x2
+#define ID0_PTFS_V8_ONLY		0x2
+#define ID0_CTTW			(1 << 14)
+#define ID0_NUMIRPT_SHIFT		16
+#define ID0_NUMIRPT_MASK		0xff
+#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)
+
+#define PIDR2_ARCH_SHIFT		4
+#define PIDR2_ARCH_MASK			0xf
+
+/* Global TLB invalidation */
+#define ARM_SMMU_GR0_STLBIALL		0x60
+#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_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) * (smmu)->pagesize)
+
+#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_TTBCR		0x30
+#define ARM_SMMU_CB_S1_MAIR0		0x38
+#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 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 RESUME_RETRY			(0 << 0)
+#define RESUME_TERMINATE		(1 << 0)
+
+#define TTBCR_EAE			(1 << 31)
+
+#define TTBCR_PASIZE_SHIFT		16
+#define TTBCR_PASIZE_MASK		0x7
+
+#define TTBCR_TG0_4K			(0 << 14)
+#define TTBCR_TG0_64K			(1 << 14)
+
+#define TTBCR_SH0_SHIFT			12
+#define TTBCR_SH0_MASK			0x3
+#define TTBCR_SH_NS			0
+#define TTBCR_SH_OS			2
+#define TTBCR_SH_IS			3
+
+#define TTBCR_ORGN0_SHIFT		10
+#define TTBCR_IRGN0_SHIFT		8
+#define TTBCR_RGN_MASK			0x3
+#define TTBCR_RGN_NC			0
+#define TTBCR_RGN_WBWA			1
+#define TTBCR_RGN_WT			2
+#define TTBCR_RGN_WB			3
+
+#define TTBCR_SL0_SHIFT			6
+#define TTBCR_SL0_MASK			0x3
+#define TTBCR_SL0_LVL_2			0
+#define TTBCR_SL0_LVL_1			1
+
+#define TTBCR_T1SZ_SHIFT		16
+#define TTBCR_T0SZ_SHIFT		0
+#define TTBCR_SZ_MASK			0xf
+
+#define TTBCR2_SEP_SHIFT		15
+#define TTBCR2_SEP_MASK			0x7
+
+#define TTBCR2_PASIZE_SHIFT		0
+#define TTBCR2_PASIZE_MASK		0x7
+
+/* Common definitions for PASize and SEP fields */
+#define TTBCR2_ADDR_32			0
+#define TTBCR2_ADDR_36			1
+#define TTBCR2_ADDR_40			2
+#define TTBCR2_ADDR_42			3
+#define TTBCR2_ADDR_44			4
+#define TTBCR2_ADDR_48			5
+
+#define MAIR_ATTR_SHIFT(n)		((n) << 3)
+#define MAIR_ATTR_MASK			0xff
+#define MAIR_ATTR_DEVICE		0x04
+#define MAIR_ATTR_NC			0x44
+#define MAIR_ATTR_WBRWA			0xff
+#define MAIR_ATTR_IDX_NC		0
+#define MAIR_ATTR_IDX_CACHE		1
+#define MAIR_ATTR_IDX_DEV		2
+
+#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)
+
+#define FSYNR0_WNR			(1 << 4)
+
+struct arm_smmu_smr {
+	u8				idx;
+	u16				mask;
+	u16				id;
+};
+
+struct arm_smmu_master {
+	struct device_node		*of_node;
+
+	/*
+	 * The following is specific to the master's position in the
+	 * SMMU chain.
+	 */
+	struct rb_node			node;
+	int				num_streamids;
+	u16				streamids[MAX_MASTER_STREAMIDS];
+
+	/*
+	 * We only need to allocate these on the root SMMU, as we
+	 * configure unmatched streams to bypass translation.
+	 */
+	struct arm_smmu_smr		*smrs;
+};
+
+struct arm_smmu_device {
+	struct device			*dev;
+	struct device_node		*parent_of_node;
+
+	void __iomem			*base;
+	unsigned long			size;
+	unsigned long			pagesize;
+
+#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)
+	u32				features;
+	int				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			input_size;
+	unsigned long			s1_output_size;
+	unsigned long			s2_output_size;
+
+	u32				num_global_irqs;
+	u32				num_context_irqs;
+	unsigned int			*irqs;
+
+	DECLARE_BITMAP(vmid_map, ARM_SMMU_NUM_VMIDS);
+
+	struct list_head		list;
+	struct rb_root			masters;
+};
+
+struct arm_smmu_cfg {
+	struct arm_smmu_device		*smmu;
+	u8				vmid;
+	u8				cbndx;
+	u8				irptndx;
+	u32				cbar;
+	pgd_t				*pgd;
+};
+
+struct arm_smmu_domain {
+	/*
+	 * A domain can span across multiple, chained SMMUs and requires
+	 * all devices within the domain to follow the same translation
+	 * path.
+	 */
+	struct arm_smmu_device		*leaf_smmu;
+	struct arm_smmu_cfg		root_cfg;
+	phys_addr_t			output_mask;
+
+	spinlock_t			lock;
+};
+
+static DEFINE_SPINLOCK(arm_smmu_devices_lock);
+static LIST_HEAD(arm_smmu_devices);
+
+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 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;
+		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->num_streamids	= masterspec->args_count;
+
+	for (i = 0; i < master->num_streamids; ++i)
+		master->streamids[i] = masterspec->args[i];
+
+	return insert_smmu_master(smmu, master);
+}
+
+static struct arm_smmu_device *find_parent_smmu(struct arm_smmu_device *smmu)
+{
+	struct arm_smmu_device *parent;
+
+	if (!smmu->parent_of_node)
+		return NULL;
+
+	spin_lock(&arm_smmu_devices_lock);
+	list_for_each_entry(parent, &arm_smmu_devices, list)
+		if (parent->dev->of_node == smmu->parent_of_node)
+			goto out_unlock;
+
+	parent = NULL;
+	dev_warn(smmu->dev,
+		 "Failed to find SMMU parent despite parent in DT\n");
+out_unlock:
+	spin_unlock(&arm_smmu_devices_lock);
+	return parent;
+}
+
+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 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 = domain->priv;
+	struct arm_smmu_cfg *root_cfg = &smmu_domain->root_cfg;
+	struct arm_smmu_device *smmu = root_cfg->smmu;
+	void __iomem *cb_base;
+
+	cb_base = ARM_SMMU_CB_BASE(smmu) + ARM_SMMU_CB(smmu, root_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%u)\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 {
+		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(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);
+
+	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_NONE;
+}
+
+static void arm_smmu_init_context_bank(struct arm_smmu_domain *smmu_domain)
+{
+	u32 reg;
+	bool stage1;
+	struct arm_smmu_cfg *root_cfg = &smmu_domain->root_cfg;
+	struct arm_smmu_device *smmu = root_cfg->smmu;
+	void __iomem *cb_base, *gr0_base, *gr1_base;
+
+	gr0_base = ARM_SMMU_GR0(smmu);
+	gr1_base = ARM_SMMU_GR1(smmu);
+	stage1 = root_cfg->cbar != CBAR_TYPE_S2_TRANS;
+	cb_base = ARM_SMMU_CB_BASE(smmu) + ARM_SMMU_CB(smmu, root_cfg->cbndx);
+
+	/* CBAR */
+	reg = root_cfg->cbar |
+	      (root_cfg->vmid << CBAR_VMID_SHIFT);
+	if (smmu->version == 1)
+	      reg |= root_cfg->irptndx << CBAR_IRPTNDX_SHIFT;
+
+	/* Use the weakest memory type, so it is overridden by the pte */
+	if (stage1)
+		reg |= (CBAR_S1_MEMATTR_WB << CBAR_S1_MEMATTR_SHIFT);
+	writel_relaxed(reg, gr1_base + ARM_SMMU_GR1_CBAR(root_cfg->cbndx));
+
+	if (smmu->version > 1) {
+		/* CBA2R */
+#ifdef CONFIG_64BIT
+		reg = CBA2R_RW64_64BIT;
+#else
+		reg = CBA2R_RW64_32BIT;
+#endif
+		writel_relaxed(reg,
+			       gr1_base + ARM_SMMU_GR1_CBA2R(root_cfg->cbndx));
+
+		/* TTBCR2 */
+		switch (smmu->input_size) {
+		case 32:
+			reg = (TTBCR2_ADDR_32 << TTBCR2_SEP_SHIFT);
+			break;
+		case 36:
+			reg = (TTBCR2_ADDR_36 << TTBCR2_SEP_SHIFT);
+			break;
+		case 39:
+			reg = (TTBCR2_ADDR_40 << TTBCR2_SEP_SHIFT);
+			break;
+		case 42:
+			reg = (TTBCR2_ADDR_42 << TTBCR2_SEP_SHIFT);
+			break;
+		case 44:
+			reg = (TTBCR2_ADDR_44 << TTBCR2_SEP_SHIFT);
+			break;
+		case 48:
+			reg = (TTBCR2_ADDR_48 << TTBCR2_SEP_SHIFT);
+			break;
+		}
+
+		switch (smmu->s1_output_size) {
+		case 32:
+			reg |= (TTBCR2_ADDR_32 << TTBCR2_PASIZE_SHIFT);
+			break;
+		case 36:
+			reg |= (TTBCR2_ADDR_36 << TTBCR2_PASIZE_SHIFT);
+			break;
+		case 39:
+			reg |= (TTBCR2_ADDR_40 << TTBCR2_PASIZE_SHIFT);
+			break;
+		case 42:
+			reg |= (TTBCR2_ADDR_42 << TTBCR2_PASIZE_SHIFT);
+			break;
+		case 44:
+			reg |= (TTBCR2_ADDR_44 << TTBCR2_PASIZE_SHIFT);
+			break;
+		case 48:
+			reg |= (TTBCR2_ADDR_48 << TTBCR2_PASIZE_SHIFT);
+			break;
+		}
+
+		if (stage1)
+			writel_relaxed(reg, cb_base + ARM_SMMU_CB_TTBCR2);
+	}
+
+	/* TTBR0 */
+	reg = __pa(root_cfg->pgd);
+#ifndef __BIG_ENDIAN
+	writel_relaxed(reg, cb_base + ARM_SMMU_CB_TTBR0_LO);
+	reg = (phys_addr_t)__pa(root_cfg->pgd) >> 32;
+	writel_relaxed(reg, cb_base + ARM_SMMU_CB_TTBR0_HI);
+#else
+	writel_relaxed(reg, cb_base + ARM_SMMU_CB_TTBR0_HI);
+	reg = (phys_addr_t)__pa(root_cfg->pgd) >> 32;
+	writel_relaxed(reg, cb_base + ARM_SMMU_CB_TTBR0_LO);
+#endif
+
+	/*
+	 * TTBCR
+	 * We use long descriptor, with inner-shareable WBWA tables in TTBR0.
+	 */
+	if (smmu->version > 1) {
+		if (PAGE_SIZE == SZ_4K)
+			reg = TTBCR_TG0_4K;
+		else
+			reg = TTBCR_TG0_64K;
+
+		if (!stage1) {
+			switch (smmu->s2_output_size) {
+			case 32:
+				reg |= (TTBCR2_ADDR_32 << TTBCR_PASIZE_SHIFT);
+				break;
+			case 36:
+				reg |= (TTBCR2_ADDR_36 << TTBCR_PASIZE_SHIFT);
+				break;
+			case 40:
+				reg |= (TTBCR2_ADDR_40 << TTBCR_PASIZE_SHIFT);
+				break;
+			case 42:
+				reg |= (TTBCR2_ADDR_42 << TTBCR_PASIZE_SHIFT);
+				break;
+			case 44:
+				reg |= (TTBCR2_ADDR_44 << TTBCR_PASIZE_SHIFT);
+				break;
+			case 48:
+				reg |= (TTBCR2_ADDR_48 << TTBCR_PASIZE_SHIFT);
+				break;
+			}
+		} else {
+			reg |= (64 - smmu->s1_output_size) << TTBCR_T0SZ_SHIFT;
+		}
+	} else {
+		reg = 0;
+	}
+
+	reg |= TTBCR_EAE |
+	      (TTBCR_SH_IS << TTBCR_SH0_SHIFT) |
+	      (TTBCR_RGN_WBWA << TTBCR_ORGN0_SHIFT) |
+	      (TTBCR_RGN_WBWA << TTBCR_IRGN0_SHIFT) |
+	      (TTBCR_SL0_LVL_1 << TTBCR_SL0_SHIFT);
+	writel_relaxed(reg, cb_base + ARM_SMMU_CB_TTBCR);
+
+	/* MAIR0 (stage-1 only) */
+	if (stage1) {
+		reg = (MAIR_ATTR_NC << MAIR_ATTR_SHIFT(MAIR_ATTR_IDX_NC)) |
+		      (MAIR_ATTR_WBRWA << MAIR_ATTR_SHIFT(MAIR_ATTR_IDX_CACHE)) |
+		      (MAIR_ATTR_DEVICE << MAIR_ATTR_SHIFT(MAIR_ATTR_IDX_DEV));
+		writel_relaxed(reg, cb_base + ARM_SMMU_CB_S1_MAIR0);
+	}
+
+	/* Nuke the TLB */
+	writel_relaxed(root_cfg->vmid, gr0_base + ARM_SMMU_GR0_TLBIVMID);
+	arm_smmu_tlb_sync(smmu);
+
+	/* 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(reg, cb_base + ARM_SMMU_CB_SCTLR);
+}
+
+static int arm_smmu_init_domain_context(struct iommu_domain *domain,
+					struct device *dev)
+{
+	int irq, ret, start;
+	struct arm_smmu_domain *smmu_domain = domain->priv;
+	struct arm_smmu_cfg *root_cfg = &smmu_domain->root_cfg;
+	struct arm_smmu_device *smmu, *parent;
+
+	/*
+	 * Walk the SMMU chain to find the root device for this chain.
+	 * We assume that no masters have translations which terminate
+	 * early, and therefore check that the root SMMU does indeed have
+	 * a StreamID for the master in question.
+	 */
+	parent = dev->archdata.iommu;
+	smmu_domain->output_mask = -1;
+	do {
+		smmu = parent;
+		smmu_domain->output_mask &= (1ULL << smmu->s2_output_size) - 1;
+	} while ((parent = find_parent_smmu(smmu)));
+
+	if (!find_smmu_master(smmu, dev->of_node)) {
+		dev_err(dev, "unable to find root SMMU for device\n");
+		return -ENODEV;
+	}
+
+	ret = __arm_smmu_alloc_bitmap(smmu->vmid_map, 0, ARM_SMMU_NUM_VMIDS);
+	if (IS_ERR_VALUE(ret))
+		return ret;
+
+	root_cfg->vmid = ret;
+	if (smmu->features & ARM_SMMU_FEAT_TRANS_NESTED) {
+		/*
+		 * We will likely want to change this if/when KVM gets
+		 * involved.
+		 */
+		root_cfg->cbar = CBAR_TYPE_S1_TRANS_S2_BYPASS;
+		start = smmu->num_s2_context_banks;
+	} else if (smmu->features & ARM_SMMU_FEAT_TRANS_S2) {
+		root_cfg->cbar = CBAR_TYPE_S2_TRANS;
+		start = 0;
+	} else {
+		root_cfg->cbar = CBAR_TYPE_S1_TRANS_S2_BYPASS;
+		start = smmu->num_s2_context_banks;
+	}
+
+	ret = __arm_smmu_alloc_bitmap(smmu->context_map, start,
+				      smmu->num_context_banks);
+	if (IS_ERR_VALUE(ret))
+		goto out_free_vmid;
+
+	root_cfg->cbndx = ret;
+
+	if (smmu->version == 1) {
+		root_cfg->irptndx = atomic_inc_return(&smmu->irptndx);
+		root_cfg->irptndx %= smmu->num_context_irqs;
+	} else {
+		root_cfg->irptndx = root_cfg->cbndx;
+	}
+
+	irq = smmu->irqs[smmu->num_global_irqs + root_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",
+			root_cfg->irptndx, irq);
+		root_cfg->irptndx = -1;
+		goto out_free_context;
+	}
+
+	root_cfg->smmu = smmu;
+	arm_smmu_init_context_bank(smmu_domain);
+	return ret;
+
+out_free_context:
+	__arm_smmu_free_bitmap(smmu->context_map, root_cfg->cbndx);
+out_free_vmid:
+	__arm_smmu_free_bitmap(smmu->vmid_map, root_cfg->vmid);
+	return ret;
+}
+
+static void arm_smmu_destroy_domain_context(struct iommu_domain *domain)
+{
+	struct arm_smmu_domain *smmu_domain = domain->priv;
+	struct arm_smmu_cfg *root_cfg = &smmu_domain->root_cfg;
+	struct arm_smmu_device *smmu = root_cfg->smmu;
+	int irq;
+
+	if (!smmu)
+		return;
+
+	if (root_cfg->irptndx != -1) {
+		irq = smmu->irqs[smmu->num_global_irqs + root_cfg->irptndx];
+		free_irq(irq, domain);
+	}
+
+	__arm_smmu_free_bitmap(smmu->vmid_map, root_cfg->vmid);
+	__arm_smmu_free_bitmap(smmu->context_map, root_cfg->cbndx);
+}
+
+static int arm_smmu_domain_init(struct iommu_domain *domain)
+{
+	struct arm_smmu_domain *smmu_domain;
+	pgd_t *pgd;
+
+	/*
+	 * 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 -ENOMEM;
+
+	pgd = kzalloc(PTRS_PER_PGD * sizeof(pgd_t), GFP_KERNEL);
+	if (!pgd)
+		goto out_free_domain;
+	smmu_domain->root_cfg.pgd = pgd;
+
+	spin_lock_init(&smmu_domain->lock);
+	domain->priv = smmu_domain;
+	return 0;
+
+out_free_domain:
+	kfree(smmu_domain);
+	return -ENOMEM;
+}
+
+static void arm_smmu_free_ptes(pmd_t *pmd)
+{
+	pgtable_t table = pmd_pgtable(*pmd);
+	pgtable_page_dtor(table);
+	__free_page(table);
+}
+
+static void arm_smmu_free_pmds(pud_t *pud)
+{
+	int i;
+	pmd_t *pmd, *pmd_base = pmd_offset(pud, 0);
+
+	pmd = pmd_base;
+	for (i = 0; i < PTRS_PER_PMD; ++i) {
+		if (pmd_none(*pmd))
+			continue;
+
+		arm_smmu_free_ptes(pmd);
+		pmd++;
+	}
+
+	pmd_free(NULL, pmd_base);
+}
+
+static void arm_smmu_free_puds(pgd_t *pgd)
+{
+	int i;
+	pud_t *pud, *pud_base = pud_offset(pgd, 0);
+
+	pud = pud_base;
+	for (i = 0; i < PTRS_PER_PUD; ++i) {
+		if (pud_none(*pud))
+			continue;
+
+		arm_smmu_free_pmds(pud);
+		pud++;
+	}
+
+	pud_free(NULL, pud_base);
+}
+
+static void arm_smmu_free_pgtables(struct arm_smmu_domain *smmu_domain)
+{
+	int i;
+	struct arm_smmu_cfg *root_cfg = &smmu_domain->root_cfg;
+	pgd_t *pgd, *pgd_base = root_cfg->pgd;
+
+	/*
+	 * Recursively free the page tables for this domain. We don't
+	 * care about speculative TLB filling, because the TLB will be
+	 * nuked next time this context bank is re-allocated and no devices
+	 * currently map to these tables.
+	 */
+	pgd = pgd_base;
+	for (i = 0; i < PTRS_PER_PGD; ++i) {
+		if (pgd_none(*pgd))
+			continue;
+		arm_smmu_free_puds(pgd);
+		pgd++;
+	}
+
+	kfree(pgd_base);
+}
+
+static void arm_smmu_domain_destroy(struct iommu_domain *domain)
+{
+	struct arm_smmu_domain *smmu_domain = domain->priv;
+	arm_smmu_destroy_domain_context(domain);
+	arm_smmu_free_pgtables(smmu_domain);
+	kfree(smmu_domain);
+}
+
+static int arm_smmu_master_configure_smrs(struct arm_smmu_device *smmu,
+					  struct arm_smmu_master *master)
+{
+	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 (master->smrs)
+		return -EEXIST;
+
+	smrs = kmalloc(sizeof(*smrs) * master->num_streamids, GFP_KERNEL);
+	if (!smrs) {
+		dev_err(smmu->dev, "failed to allocate %d SMRs for master %s\n",
+			master->num_streamids, master->of_node->name);
+		return -ENOMEM;
+	}
+
+	/* Allocate the SMRs on the root SMMU */
+	for (i = 0; i < master->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	= master->streamids[i],
+		};
+	}
+
+	/* It worked! Now, poke the actual hardware */
+	for (i = 0; i < master->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));
+	}
+
+	master->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 *master)
+{
+	int i;
+	void __iomem *gr0_base = ARM_SMMU_GR0(smmu);
+	struct arm_smmu_smr *smrs = master->smrs;
+
+	/* Invalidate the SMRs before freeing back to the allocator */
+	for (i = 0; i < master->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);
+	}
+
+	master->smrs = NULL;
+	kfree(smrs);
+}
+
+static void arm_smmu_bypass_stream_mapping(struct arm_smmu_device *smmu,
+					   struct arm_smmu_master *master)
+{
+	int i;
+	void __iomem *gr0_base = ARM_SMMU_GR0(smmu);
+
+	for (i = 0; i < master->num_streamids; ++i) {
+		u16 sid = master->streamids[i];
+		writel_relaxed(S2CR_TYPE_BYPASS,
+			       gr0_base + ARM_SMMU_GR0_S2CR(sid));
+	}
+}
+
+static int arm_smmu_domain_add_master(struct arm_smmu_domain *smmu_domain,
+				      struct arm_smmu_master *master)
+{
+	int i, ret;
+	struct arm_smmu_device *parent, *smmu = smmu_domain->root_cfg.smmu;
+	void __iomem *gr0_base = ARM_SMMU_GR0(smmu);
+
+	ret = arm_smmu_master_configure_smrs(smmu, master);
+	if (ret)
+		return ret;
+
+	/* Bypass the leaves */
+	smmu = smmu_domain->leaf_smmu;
+	while ((parent = find_parent_smmu(smmu))) {
+		/*
+		 * We won't have a StreamID match for anything but the root
+		 * smmu, so we only need to worry about StreamID indexing,
+		 * where we must install bypass entries in the S2CRs.
+		 */
+		if (smmu->features & ARM_SMMU_FEAT_STREAM_MATCH)
+			continue;
+
+		arm_smmu_bypass_stream_mapping(smmu, master);
+		smmu = parent;
+	}
+
+	/* Now we're at the root, time to point at our context bank */
+	for (i = 0; i < master->num_streamids; ++i) {
+		u32 idx, s2cr;
+		idx = master->smrs ? master->smrs[i].idx : master->streamids[i];
+		s2cr = (S2CR_TYPE_TRANS << S2CR_TYPE_SHIFT) |
+		       (smmu_domain->root_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 *master)
+{
+	struct arm_smmu_device *smmu = smmu_domain->root_cfg.smmu;
+
+	/*
+	 * We *must* clear the S2CR first, because freeing the SMR means
+	 * that it can be re-allocated immediately.
+	 */
+	arm_smmu_bypass_stream_mapping(smmu, master);
+	arm_smmu_master_free_smrs(smmu, master);
+}
+
+static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
+{
+	int ret = -EINVAL;
+	struct arm_smmu_domain *smmu_domain = domain->priv;
+	struct arm_smmu_device *device_smmu = dev->archdata.iommu;
+	struct arm_smmu_master *master;
+
+	if (!device_smmu) {
+		dev_err(dev, "cannot attach to SMMU, is it on the same bus?\n");
+		return -ENXIO;
+	}
+
+	/*
+	 * Sanity check the domain. We don't currently support domains
+	 * that cross between different SMMU chains.
+	 */
+	spin_lock(&smmu_domain->lock);
+	if (!smmu_domain->leaf_smmu) {
+		/* Now that we have a master, we can finalise the domain */
+		ret = arm_smmu_init_domain_context(domain, dev);
+		if (IS_ERR_VALUE(ret))
+			goto err_unlock;
+
+		smmu_domain->leaf_smmu = device_smmu;
+	} else if (smmu_domain->leaf_smmu != device_smmu) {
+		dev_err(dev,
+			"cannot attach to SMMU %s whilst already attached to domain on SMMU %s\n",
+			dev_name(smmu_domain->leaf_smmu->dev),
+			dev_name(device_smmu->dev));
+		goto err_unlock;
+	}
+	spin_unlock(&smmu_domain->lock);
+
+	/* Looks ok, so add the device to the domain */
+	master = find_smmu_master(smmu_domain->leaf_smmu, dev->of_node);
+	if (!master)
+		return -ENODEV;
+
+	return arm_smmu_domain_add_master(smmu_domain, master);
+
+err_unlock:
+	spin_unlock(&smmu_domain->lock);
+	return ret;
+}
+
+static void arm_smmu_detach_dev(struct iommu_domain *domain, struct device *dev)
+{
+	struct arm_smmu_domain *smmu_domain = domain->priv;
+	struct arm_smmu_master *master;
+
+	master = find_smmu_master(smmu_domain->leaf_smmu, dev->of_node);
+	if (master)
+		arm_smmu_domain_remove_master(smmu_domain, master);
+}
+
+static void arm_smmu_flush_pgtable(struct arm_smmu_device *smmu, void *addr,
+				   size_t size)
+{
+	unsigned long offset = (unsigned long)addr & ~PAGE_MASK;
+
+	/*
+	 * 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.
+	 */
+	if (!(smmu->features & ARM_SMMU_FEAT_COHERENT_WALK))
+		dma_map_page(smmu->dev, virt_to_page(addr), offset, size,
+			     DMA_TO_DEVICE);
+}
+
+static bool arm_smmu_pte_is_contiguous_range(unsigned long addr,
+					     unsigned long end)
+{
+	return !(addr & ~ARM_SMMU_PTE_CONT_MASK) &&
+		(addr + ARM_SMMU_PTE_CONT_SIZE <= end);
+}
+
+static int arm_smmu_alloc_init_pte(struct arm_smmu_device *smmu, pmd_t *pmd,
+				   unsigned long addr, unsigned long end,
+				   unsigned long pfn, int flags, int stage)
+{
+	pte_t *pte, *start;
+	pteval_t pteval = ARM_SMMU_PTE_PAGE | ARM_SMMU_PTE_AF;
+
+	if (pmd_none(*pmd)) {
+		/* Allocate a new set of tables */
+		pgtable_t table = alloc_page(PGALLOC_GFP);
+		if (!table)
+			return -ENOMEM;
+
+		arm_smmu_flush_pgtable(smmu, page_address(table),
+				       ARM_SMMU_PTE_HWTABLE_SIZE);
+		pgtable_page_ctor(table);
+		pmd_populate(NULL, pmd, table);
+		arm_smmu_flush_pgtable(smmu, pmd, sizeof(*pmd));
+	}
+
+	if (stage == 1) {
+		pteval |= ARM_SMMU_PTE_AP_UNPRIV;
+		if (!(flags & IOMMU_WRITE) && (flags & IOMMU_READ))
+			pteval |= ARM_SMMU_PTE_AP_RDONLY;
+
+		if (flags & IOMMU_CACHE)
+			pteval |= (MAIR_ATTR_IDX_CACHE <<
+				   ARM_SMMU_PTE_ATTRINDX_SHIFT);
+	} else {
+		pteval |= ARM_SMMU_PTE_HAP_FAULT;
+		if (flags & IOMMU_READ)
+			pteval |= ARM_SMMU_PTE_HAP_READ;
+		if (flags & IOMMU_WRITE)
+			pteval |= ARM_SMMU_PTE_HAP_WRITE;
+		if (flags & IOMMU_CACHE)
+			pteval |= ARM_SMMU_PTE_MEMATTR_OIWB;
+		else
+			pteval |= ARM_SMMU_PTE_MEMATTR_NC;
+	}
+
+	/* If no access, create a faulting entry to avoid TLB fills */
+	if (!(flags & (IOMMU_READ | IOMMU_WRITE)))
+		pteval &= ~ARM_SMMU_PTE_PAGE;
+
+	pteval |= ARM_SMMU_PTE_SH_IS;
+	start = pmd_page_vaddr(*pmd) + pte_index(addr);
+	pte = start;
+
+	/*
+	 * Install the page table entries. This is fairly complicated
+	 * since we attempt to make use of the contiguous hint in the
+	 * ptes where possible. The contiguous hint indicates a series
+	 * of ARM_SMMU_PTE_CONT_ENTRIES ptes mapping a physically
+	 * contiguous region with the following constraints:
+	 *
+	 *   - The region start is aligned to ARM_SMMU_PTE_CONT_SIZE
+	 *   - Each pte in the region has the contiguous hint bit set
+	 *
+	 * This complicates unmapping (also handled by this code, when
+	 * neither IOMMU_READ or IOMMU_WRITE are set) because it is
+	 * possible, yet highly unlikely, that a client may unmap only
+	 * part of a contiguous range. This requires clearing of the
+	 * contiguous hint bits in the range before installing the new
+	 * faulting entries.
+	 *
+	 * Note that re-mapping an address range without first unmapping
+	 * it is not supported, so TLB invalidation is not required here
+	 * and is instead performed at unmap and domain-init time.
+	 */
+	do {
+		int i = 1;
+		pteval &= ~ARM_SMMU_PTE_CONT;
+
+		if (arm_smmu_pte_is_contiguous_range(addr, end)) {
+			i = ARM_SMMU_PTE_CONT_ENTRIES;
+			pteval |= ARM_SMMU_PTE_CONT;
+		} else if (pte_val(*pte) &
+			   (ARM_SMMU_PTE_CONT | ARM_SMMU_PTE_PAGE)) {
+			int j;
+			pte_t *cont_start;
+			unsigned long idx = pte_index(addr);
+
+			idx &= ~(ARM_SMMU_PTE_CONT_ENTRIES - 1);
+			cont_start = pmd_page_vaddr(*pmd) + idx;
+			for (j = 0; j < ARM_SMMU_PTE_CONT_ENTRIES; ++j)
+				pte_val(*(cont_start + j)) &= ~ARM_SMMU_PTE_CONT;
+
+			arm_smmu_flush_pgtable(smmu, cont_start,
+					       sizeof(*pte) *
+					       ARM_SMMU_PTE_CONT_ENTRIES);
+		}
+
+		do {
+			*pte = pfn_pte(pfn, __pgprot(pteval));
+		} while (pte++, pfn++, addr += PAGE_SIZE, --i);
+	} while (addr != end);
+
+	arm_smmu_flush_pgtable(smmu, start, sizeof(*pte) * (pte - start));
+	return 0;
+}
+
+static int arm_smmu_alloc_init_pmd(struct arm_smmu_device *smmu, pud_t *pud,
+				   unsigned long addr, unsigned long end,
+				   phys_addr_t phys, int flags, int stage)
+{
+	int ret;
+	pmd_t *pmd;
+	unsigned long next, pfn = __phys_to_pfn(phys);
+
+#ifndef __PAGETABLE_PMD_FOLDED
+	if (pud_none(*pud)) {
+		pmd = pmd_alloc_one(NULL, addr);
+		if (!pmd)
+			return -ENOMEM;
+	} else
+#endif
+		pmd = pmd_offset(pud, addr);
+
+	do {
+		next = pmd_addr_end(addr, end);
+		ret = arm_smmu_alloc_init_pte(smmu, pmd, addr, end, pfn,
+					      flags, stage);
+		pud_populate(NULL, pud, pmd);
+		arm_smmu_flush_pgtable(smmu, pud, sizeof(*pud));
+		phys += next - addr;
+	} while (pmd++, addr = next, addr < end);
+
+	return ret;
+}
+
+static int arm_smmu_alloc_init_pud(struct arm_smmu_device *smmu, pgd_t *pgd,
+				   unsigned long addr, unsigned long end,
+				   phys_addr_t phys, int flags, int stage)
+{
+	int ret = 0;
+	pud_t *pud;
+	unsigned long next;
+
+#ifndef __PAGETABLE_PUD_FOLDED
+	if (pgd_none(*pgd)) {
+		pud = pud_alloc_one(NULL, addr);
+		if (!pud)
+			return -ENOMEM;
+	} else
+#endif
+		pud = pud_offset(pgd, addr);
+
+	do {
+		next = pud_addr_end(addr, end);
+		ret = arm_smmu_alloc_init_pmd(smmu, pud, addr, next, phys,
+					      flags, stage);
+		pgd_populate(NULL, pud, pgd);
+		arm_smmu_flush_pgtable(smmu, pgd, sizeof(*pgd));
+		phys += next - addr;
+	} while (pud++, addr = next, addr < end);
+
+	return ret;
+}
+
+static int arm_smmu_handle_mapping(struct arm_smmu_domain *smmu_domain,
+				   unsigned long iova, phys_addr_t paddr,
+				   size_t size, int flags)
+{
+	int ret, stage;
+	unsigned long end;
+	phys_addr_t input_mask, output_mask;
+	struct arm_smmu_cfg *root_cfg = &smmu_domain->root_cfg;
+	pgd_t *pgd = root_cfg->pgd;
+	struct arm_smmu_device *smmu = root_cfg->smmu;
+
+	if (root_cfg->cbar == CBAR_TYPE_S2_TRANS) {
+		stage = 2;
+		output_mask = (1ULL << smmu->s2_output_size) - 1;
+	} else {
+		stage = 1;
+		output_mask = (1ULL << smmu->s1_output_size) - 1;
+	}
+
+	if (!pgd)
+		return -EINVAL;
+
+	if (size & ~PAGE_MASK)
+		return -EINVAL;
+
+	input_mask = (1ULL << smmu->input_size) - 1;
+	if ((phys_addr_t)iova & ~input_mask)
+		return -ERANGE;
+
+	if (paddr & ~output_mask)
+		return -ERANGE;
+
+	spin_lock(&smmu_domain->lock);
+	pgd += pgd_index(iova);
+	end = iova + size;
+	do {
+		unsigned long next = pgd_addr_end(iova, end);
+
+		ret = arm_smmu_alloc_init_pud(smmu, pgd, iova, next, paddr,
+					      flags, stage);
+		if (ret)
+			goto out_unlock;
+
+		paddr += next - iova;
+		iova = next;
+	} while (pgd++, iova != end);
+
+out_unlock:
+	spin_unlock(&smmu_domain->lock);
+
+	/* Ensure new page tables are visible to the hardware walker */
+	if (smmu->features & ARM_SMMU_FEAT_COHERENT_WALK)
+		dsb();
+
+	return ret;
+}
+
+static int arm_smmu_map(struct iommu_domain *domain, unsigned long iova,
+			phys_addr_t paddr, size_t size, int flags)
+{
+	struct arm_smmu_domain *smmu_domain = domain->priv;
+	struct arm_smmu_device *smmu = smmu_domain->leaf_smmu;
+
+	if (!smmu_domain || !smmu)
+		return -ENODEV;
+
+	/* Check for silent address truncation up the SMMU chain. */
+	if ((phys_addr_t)iova & ~smmu_domain->output_mask)
+		return -ERANGE;
+
+	return arm_smmu_handle_mapping(smmu_domain, iova, paddr, size, flags);
+}
+
+static size_t arm_smmu_unmap(struct iommu_domain *domain, unsigned long iova,
+			     size_t size)
+{
+	int ret;
+	struct arm_smmu_domain *smmu_domain = domain->priv;
+	struct arm_smmu_cfg *root_cfg = &smmu_domain->root_cfg;
+	struct arm_smmu_device *smmu = root_cfg->smmu;
+	void __iomem *gr0_base = ARM_SMMU_GR0(smmu);
+
+	ret = arm_smmu_handle_mapping(smmu_domain, iova, 0, size, 0);
+	writel_relaxed(root_cfg->vmid, gr0_base + ARM_SMMU_GR0_TLBIVMID);
+	arm_smmu_tlb_sync(smmu);
+	return ret ? ret : size;
+}
+
+static phys_addr_t arm_smmu_iova_to_phys(struct iommu_domain *domain,
+					 dma_addr_t iova)
+{
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+	pte_t *pte;
+	struct arm_smmu_domain *smmu_domain = domain->priv;
+	struct arm_smmu_cfg *root_cfg = &smmu_domain->root_cfg;
+	struct arm_smmu_device *smmu = root_cfg->smmu;
+
+	spin_lock(&smmu_domain->lock);
+	pgd = root_cfg->pgd;
+	if (!pgd)
+		goto err_unlock;
+
+	pgd += pgd_index(iova);
+	if (pgd_none_or_clear_bad(pgd))
+		goto err_unlock;
+
+	pud = pud_offset(pgd, iova);
+	if (pud_none_or_clear_bad(pud))
+		goto err_unlock;
+
+	pmd = pmd_offset(pud, iova);
+	if (pmd_none_or_clear_bad(pmd))
+		goto err_unlock;
+
+	pte = pmd_page_vaddr(*pmd) + pte_index(iova);
+	if (pte_none(pte))
+		goto err_unlock;
+
+	spin_unlock(&smmu_domain->lock);
+	return __pfn_to_phys(pte_pfn(*pte)) | (iova & ~PAGE_MASK);
+
+err_unlock:
+	spin_unlock(&smmu_domain->lock);
+	dev_warn(smmu->dev,
+		 "invalid (corrupt?) page tables detected for iova 0x%llx\n",
+		 (unsigned long long)iova);
+	return -EINVAL;
+}
+
+static int arm_smmu_domain_has_cap(struct iommu_domain *domain,
+				   unsigned long cap)
+{
+	unsigned long caps = 0;
+	struct arm_smmu_domain *smmu_domain = domain->priv;
+
+	if (smmu_domain->root_cfg.smmu->features & ARM_SMMU_FEAT_COHERENT_WALK)
+		caps |= IOMMU_CAP_CACHE_COHERENCY;
+
+	return !!(cap & caps);
+}
+
+static int arm_smmu_add_device(struct device *dev)
+{
+	struct arm_smmu_device *child, *parent, *smmu;
+	struct arm_smmu_master *master = NULL;
+
+	spin_lock(&arm_smmu_devices_lock);
+	list_for_each_entry(parent, &arm_smmu_devices, list) {
+		smmu = parent;
+
+		/* Try to find a child of the current SMMU. */
+		list_for_each_entry(child, &arm_smmu_devices, list) {
+			if (child->parent_of_node == parent->dev->of_node) {
+				/* Does the child sit above our master? */
+				master = find_smmu_master(child, dev->of_node);
+				if (master) {
+					smmu = NULL;
+					break;
+				}
+			}
+		}
+
+		/* We found some children, so keep searching. */
+		if (!smmu) {
+			master = NULL;
+			continue;
+		}
+
+		master = find_smmu_master(smmu, dev->of_node);
+		if (master)
+			break;
+	}
+	spin_unlock(&arm_smmu_devices_lock);
+
+	if (!master)
+		return -ENODEV;
+
+	dev->archdata.iommu = smmu;
+	return 0;
+}
+
+static void arm_smmu_remove_device(struct device *dev)
+{
+	dev->archdata.iommu = NULL;
+}
+
+static struct iommu_ops arm_smmu_ops = {
+	.domain_init	= arm_smmu_domain_init,
+	.domain_destroy	= arm_smmu_domain_destroy,
+	.attach_dev	= arm_smmu_attach_dev,
+	.detach_dev	= arm_smmu_detach_dev,
+	.map		= arm_smmu_map,
+	.unmap		= arm_smmu_unmap,
+	.iova_to_phys	= arm_smmu_iova_to_phys,
+	.domain_has_cap	= arm_smmu_domain_has_cap,
+	.add_device	= arm_smmu_add_device,
+	.remove_device	= arm_smmu_remove_device,
+	.pgsize_bitmap	= (SECTION_SIZE |
+			   ARM_SMMU_PTE_CONT_SIZE |
+			   PAGE_SIZE),
+};
+
+static void arm_smmu_device_reset(struct arm_smmu_device *smmu)
+{
+	void __iomem *gr0_base = ARM_SMMU_GR0(smmu);
+	int i = 0;
+	u32 scr0 = readl_relaxed(gr0_base + ARM_SMMU_GR0_sCR0);
+
+	/* Mark all SMRn as invalid and all S2CRn as bypass */
+	for (i = 0; i < smmu->num_mapping_groups; ++i) {
+		writel_relaxed(~SMR_VALID, gr0_base + ARM_SMMU_GR0_SMR(i));
+		writel_relaxed(S2CR_TYPE_BYPASS, gr0_base + ARM_SMMU_GR0_S2CR(i));
+	}
+
+	/* Invalidate the TLB, just in case */
+	writel_relaxed(0, gr0_base + ARM_SMMU_GR0_STLBIALL);
+	writel_relaxed(0, gr0_base + ARM_SMMU_GR0_TLBIALLH);
+	writel_relaxed(0, gr0_base + ARM_SMMU_GR0_TLBIALLNSNH);
+
+	/* Enable fault reporting */
+	scr0 |= (sCR0_GFRE | sCR0_GFIE | sCR0_GCFGFRE | sCR0_GCFGFIE);
+
+	/* Disable TLB broadcasting. */
+	scr0 |= (sCR0_VMIDPNE | sCR0_PTM);
+
+	/* Enable client access, but bypass when no mapping is found */
+	scr0 &= ~(sCR0_CLIENTPD | sCR0_USFCFG);
+
+	/* Disable forced broadcasting */
+	scr0 &= ~sCR0_FB;
+
+	/* Don't upgrade barriers */
+	scr0 &= ~(sCR0_BSU_MASK << sCR0_BSU_SHIFT);
+
+	/* Push the button */
+	arm_smmu_tlb_sync(smmu);
+	writel(scr0, gr0_base + 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");
+
+	/* Primecell ID */
+	id = readl_relaxed(gr0_base + ARM_SMMU_GR0_PIDR2);
+	smmu->version = ((id >> PIDR2_ARCH_SHIFT) & PIDR2_ARCH_MASK) + 1;
+	dev_notice(smmu->dev, "SMMUv%d with:\n", smmu->version);
+
+	/* ID0 */
+	id = readl_relaxed(gr0_base + ARM_SMMU_GR0_ID0);
+#ifndef CONFIG_64BIT
+	if (((id >> ID0_PTFS_SHIFT) & ID0_PTFS_MASK) == ID0_PTFS_V8_ONLY) {
+		dev_err(smmu->dev, "\tno v7 descriptor support!\n");
+		return -ENODEV;
+	}
+#endif
+	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 |
+		 ARM_SMMU_FEAT_TRANS_NESTED))) {
+		dev_err(smmu->dev, "\tno translation support!\n");
+		return -ENODEV;
+	}
+
+	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);
+	}
+
+	/* ID1 */
+	id = readl_relaxed(gr0_base + ARM_SMMU_GR0_ID1);
+	smmu->pagesize = (id & ID1_PAGESIZE) ? SZ_64K : SZ_4K;
+
+	/* Check that we ioremapped enough */
+	size = 1 << (((id >> ID1_NUMPAGENDXB_SHIFT) & ID1_NUMPAGENDXB_MASK) + 1);
+	size *= (smmu->pagesize << 1);
+	if (smmu->size < size)
+		dev_warn(smmu->dev,
+			 "device is 0x%lx bytes but only mapped 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);
+
+	/*
+	 * Stage-1 output limited by stage-2 input size due to pgd
+	 * allocation (PTRS_PER_PGD).
+	 */
+#ifdef CONFIG_64BIT
+	/* Current maximum output size of 39 bits */
+	smmu->s1_output_size = min(39UL, size);
+#else
+	smmu->s1_output_size = min(32UL, size);
+#endif
+
+	/* The stage-2 output mask is also applied for bypass */
+	size = arm_smmu_id_size_to_bits((id >> ID2_OAS_SHIFT) & ID2_OAS_MASK);
+	smmu->s2_output_size = min((unsigned long)PHYS_MASK_SHIFT, size);
+
+	if (smmu->version == 1) {
+		smmu->input_size = 32;
+	} else {
+#ifdef CONFIG_64BIT
+		size = (id >> ID2_UBS_SHIFT) & ID2_UBS_MASK;
+		size = min(39, arm_smmu_id_size_to_bits(size));
+#else
+		size = 32;
+#endif
+		smmu->input_size = size;
+
+		if ((PAGE_SIZE == SZ_4K && !(id & ID2_PTFS_4K)) ||
+		    (PAGE_SIZE == SZ_64K && !(id & ID2_PTFS_64K)) ||
+		    (PAGE_SIZE != SZ_4K && PAGE_SIZE != SZ_64K)) {
+			dev_err(smmu->dev, "CPU page size 0x%lx unsupported\n",
+				PAGE_SIZE);
+			return -ENODEV;
+		}
+	}
+
+	dev_notice(smmu->dev,
+		   "\t%lu-bit VA, %lu-bit IPA, %lu-bit PA\n",
+		   smmu->input_size, smmu->s1_output_size, smmu->s2_output_size);
+	return 0;
+}
+
+static int arm_smmu_device_dt_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	struct arm_smmu_device *smmu;
+	struct device_node *dev_node;
+	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;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(dev, "missing base address/size\n");
+		return -ENODEV;
+	}
+
+	smmu->size = resource_size(res);
+	smmu->base = devm_request_and_ioremap(dev, res);
+	if (!smmu->base)
+		return -EADDRNOTAVAIL;
+
+	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 (num_irqs < smmu->num_global_irqs) {
+		dev_warn(dev, "found %d interrupts but expected at least %d\n",
+			 num_irqs, smmu->num_global_irqs);
+		smmu->num_global_irqs = num_irqs;
+	}
+	smmu->num_context_irqs = num_irqs - smmu->num_global_irqs;
+
+	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;
+	}
+
+	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);
+
+	if ((dev_node = of_parse_phandle(dev->of_node, "smmu-parent", 0)))
+		smmu->parent_of_node = dev_node;
+
+	err = arm_smmu_device_cfg_probe(smmu);
+	if (err)
+		goto out_put_parent;
+
+	if (smmu->version > 1 &&
+	    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);
+		goto out_put_parent;
+	}
+
+	arm_smmu_device_reset(smmu);
+
+	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);
+	return 0;
+
+out_free_irqs:
+	while (i--)
+		free_irq(smmu->irqs[i], smmu);
+
+out_put_parent:
+	if (smmu->parent_of_node)
+		of_node_put(smmu->parent_of_node);
+
+out_put_masters:
+	for (node = rb_first(&smmu->masters); node; node = rb_next(node)) {
+		struct arm_smmu_master *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;
+
+	if (smmu->parent_of_node)
+		of_node_put(smmu->parent_of_node);
+
+	for (node = rb_first(&smmu->masters); node; node = rb_next(node)) {
+		struct arm_smmu_master *master;
+		master = container_of(node, struct arm_smmu_master, node);
+		of_node_put(master->of_node);
+	}
+
+	if (!bitmap_empty(smmu->vmid_map, ARM_SMMU_NUM_VMIDS))
+		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(smmu) + ARM_SMMU_GR0_sCR0);
+	return 0;
+}
+
+#ifdef CONFIG_OF
+static struct of_device_id arm_smmu_of_match[] = {
+	{ .compatible = "arm,smmu-v1", },
+	{ .compatible = "arm,smmu-v2", },
+	{ .compatible = "arm,mmu-400", },
+	{ .compatible = "arm,mmu-500", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, arm_smmu_of_match);
+#endif
+
+static struct platform_driver arm_smmu_driver = {
+	.driver	= {
+		.owner		= THIS_MODULE,
+		.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)
+{
+	int ret;
+
+	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);
+
+	if (!iommu_present(&amba_bustype));
+		bus_set_iommu(&amba_bustype, &arm_smmu_ops);
+
+	return 0;
+}
+
+static void __exit arm_smmu_exit(void)
+{
+	return platform_driver_unregister(&arm_smmu_driver);
+}
+
+module_init(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");