[Xen-devel,RFC,04/11] Import iort.c and acpi_iort.h

Message ID 20180102092809.1841-5-manish.jaggi@linaro.org
State New
Headers show
Series
  • acpi: arm: IORT Support for Xen
Related show

Commit Message

Manish Jaggi Jan. 2, 2018, 9:28 a.m.
From: Manish Jaggi <manish.jaggi@linaro.org>

Import iort.c and acpi_iort.h from linux kernel tag v4.14

Signed-off-by: Manish Jaggi <manish.jaggi@linaro.org>
---
 xen/drivers/acpi/arm/iort.c  | 1279 ++++++++++++++++++++++++++++++++++++++++++
 xen/include/acpi/acpi_iort.h |   57 ++
 2 files changed, 1336 insertions(+)

Patch

diff --git a/xen/drivers/acpi/arm/iort.c b/xen/drivers/acpi/arm/iort.c
new file mode 100644
index 0000000000..de56394dd1
--- /dev/null
+++ b/xen/drivers/acpi/arm/iort.c
@@ -0,0 +1,1279 @@ 
+/*
+ * Copyright (C) 2016, Semihalf
+ *	Author: Tomasz Nowicki <tn@semihalf.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ *
+ * This file implements early detection/parsing of I/O mapping
+ * reported to OS through firmware via I/O Remapping Table (IORT)
+ * IORT document number: ARM DEN 0049A
+ */
+
+#define pr_fmt(fmt)	"ACPI: IORT: " fmt
+
+#include <linux/acpi_iort.h>
+#include <linux/iommu.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#define IORT_TYPE_MASK(type)	(1 << (type))
+#define IORT_MSI_TYPE		(1 << ACPI_IORT_NODE_ITS_GROUP)
+#define IORT_IOMMU_TYPE		((1 << ACPI_IORT_NODE_SMMU) |	\
+				(1 << ACPI_IORT_NODE_SMMU_V3))
+
+/* Until ACPICA headers cover IORT rev. C */
+#ifndef ACPI_IORT_SMMU_V3_CAVIUM_CN99XX
+#define ACPI_IORT_SMMU_V3_CAVIUM_CN99XX		0x2
+#endif
+
+struct iort_its_msi_chip {
+	struct list_head	list;
+	struct fwnode_handle	*fw_node;
+	u32			translation_id;
+};
+
+struct iort_fwnode {
+	struct list_head list;
+	struct acpi_iort_node *iort_node;
+	struct fwnode_handle *fwnode;
+};
+static LIST_HEAD(iort_fwnode_list);
+static DEFINE_SPINLOCK(iort_fwnode_lock);
+
+/**
+ * iort_set_fwnode() - Create iort_fwnode and use it to register
+ *		       iommu data in the iort_fwnode_list
+ *
+ * @node: IORT table node associated with the IOMMU
+ * @fwnode: fwnode associated with the IORT node
+ *
+ * Returns: 0 on success
+ *          <0 on failure
+ */
+static inline int iort_set_fwnode(struct acpi_iort_node *iort_node,
+				  struct fwnode_handle *fwnode)
+{
+	struct iort_fwnode *np;
+
+	np = kzalloc(sizeof(struct iort_fwnode), GFP_ATOMIC);
+
+	if (WARN_ON(!np))
+		return -ENOMEM;
+
+	INIT_LIST_HEAD(&np->list);
+	np->iort_node = iort_node;
+	np->fwnode = fwnode;
+
+	spin_lock(&iort_fwnode_lock);
+	list_add_tail(&np->list, &iort_fwnode_list);
+	spin_unlock(&iort_fwnode_lock);
+
+	return 0;
+}
+
+/**
+ * iort_get_fwnode() - Retrieve fwnode associated with an IORT node
+ *
+ * @node: IORT table node to be looked-up
+ *
+ * Returns: fwnode_handle pointer on success, NULL on failure
+ */
+static inline
+struct fwnode_handle *iort_get_fwnode(struct acpi_iort_node *node)
+{
+	struct iort_fwnode *curr;
+	struct fwnode_handle *fwnode = NULL;
+
+	spin_lock(&iort_fwnode_lock);
+	list_for_each_entry(curr, &iort_fwnode_list, list) {
+		if (curr->iort_node == node) {
+			fwnode = curr->fwnode;
+			break;
+		}
+	}
+	spin_unlock(&iort_fwnode_lock);
+
+	return fwnode;
+}
+
+/**
+ * iort_delete_fwnode() - Delete fwnode associated with an IORT node
+ *
+ * @node: IORT table node associated with fwnode to delete
+ */
+static inline void iort_delete_fwnode(struct acpi_iort_node *node)
+{
+	struct iort_fwnode *curr, *tmp;
+
+	spin_lock(&iort_fwnode_lock);
+	list_for_each_entry_safe(curr, tmp, &iort_fwnode_list, list) {
+		if (curr->iort_node == node) {
+			list_del(&curr->list);
+			kfree(curr);
+			break;
+		}
+	}
+	spin_unlock(&iort_fwnode_lock);
+}
+
+typedef acpi_status (*iort_find_node_callback)
+	(struct acpi_iort_node *node, void *context);
+
+/* Root pointer to the mapped IORT table */
+static struct acpi_table_header *iort_table;
+
+static LIST_HEAD(iort_msi_chip_list);
+static DEFINE_SPINLOCK(iort_msi_chip_lock);
+
+/**
+ * iort_register_domain_token() - register domain token and related ITS ID
+ * to the list from where we can get it back later on.
+ * @trans_id: ITS ID.
+ * @fw_node: Domain token.
+ *
+ * Returns: 0 on success, -ENOMEM if no memory when allocating list element
+ */
+int iort_register_domain_token(int trans_id, struct fwnode_handle *fw_node)
+{
+	struct iort_its_msi_chip *its_msi_chip;
+
+	its_msi_chip = kzalloc(sizeof(*its_msi_chip), GFP_KERNEL);
+	if (!its_msi_chip)
+		return -ENOMEM;
+
+	its_msi_chip->fw_node = fw_node;
+	its_msi_chip->translation_id = trans_id;
+
+	spin_lock(&iort_msi_chip_lock);
+	list_add(&its_msi_chip->list, &iort_msi_chip_list);
+	spin_unlock(&iort_msi_chip_lock);
+
+	return 0;
+}
+
+/**
+ * iort_deregister_domain_token() - Deregister domain token based on ITS ID
+ * @trans_id: ITS ID.
+ *
+ * Returns: none.
+ */
+void iort_deregister_domain_token(int trans_id)
+{
+	struct iort_its_msi_chip *its_msi_chip, *t;
+
+	spin_lock(&iort_msi_chip_lock);
+	list_for_each_entry_safe(its_msi_chip, t, &iort_msi_chip_list, list) {
+		if (its_msi_chip->translation_id == trans_id) {
+			list_del(&its_msi_chip->list);
+			kfree(its_msi_chip);
+			break;
+		}
+	}
+	spin_unlock(&iort_msi_chip_lock);
+}
+
+/**
+ * iort_find_domain_token() - Find domain token based on given ITS ID
+ * @trans_id: ITS ID.
+ *
+ * Returns: domain token when find on the list, NULL otherwise
+ */
+struct fwnode_handle *iort_find_domain_token(int trans_id)
+{
+	struct fwnode_handle *fw_node = NULL;
+	struct iort_its_msi_chip *its_msi_chip;
+
+	spin_lock(&iort_msi_chip_lock);
+	list_for_each_entry(its_msi_chip, &iort_msi_chip_list, list) {
+		if (its_msi_chip->translation_id == trans_id) {
+			fw_node = its_msi_chip->fw_node;
+			break;
+		}
+	}
+	spin_unlock(&iort_msi_chip_lock);
+
+	return fw_node;
+}
+
+static struct acpi_iort_node *iort_scan_node(enum acpi_iort_node_type type,
+					     iort_find_node_callback callback,
+					     void *context)
+{
+	struct acpi_iort_node *iort_node, *iort_end;
+	struct acpi_table_iort *iort;
+	int i;
+
+	if (!iort_table)
+		return NULL;
+
+	/* Get the first IORT node */
+	iort = (struct acpi_table_iort *)iort_table;
+	iort_node = ACPI_ADD_PTR(struct acpi_iort_node, iort,
+				 iort->node_offset);
+	iort_end = ACPI_ADD_PTR(struct acpi_iort_node, iort_table,
+				iort_table->length);
+
+	for (i = 0; i < iort->node_count; i++) {
+		if (WARN_TAINT(iort_node >= iort_end, TAINT_FIRMWARE_WORKAROUND,
+			       "IORT node pointer overflows, bad table!\n"))
+			return NULL;
+
+		if (iort_node->type == type &&
+		    ACPI_SUCCESS(callback(iort_node, context)))
+			return iort_node;
+
+		iort_node = ACPI_ADD_PTR(struct acpi_iort_node, iort_node,
+					 iort_node->length);
+	}
+
+	return NULL;
+}
+
+static acpi_status iort_match_node_callback(struct acpi_iort_node *node,
+					    void *context)
+{
+	struct device *dev = context;
+	acpi_status status = AE_NOT_FOUND;
+
+	if (node->type == ACPI_IORT_NODE_NAMED_COMPONENT) {
+		struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER, NULL };
+		struct acpi_device *adev = to_acpi_device_node(dev->fwnode);
+		struct acpi_iort_named_component *ncomp;
+
+		if (!adev)
+			goto out;
+
+		status = acpi_get_name(adev->handle, ACPI_FULL_PATHNAME, &buf);
+		if (ACPI_FAILURE(status)) {
+			dev_warn(dev, "Can't get device full path name\n");
+			goto out;
+		}
+
+		ncomp = (struct acpi_iort_named_component *)node->node_data;
+		status = !strcmp(ncomp->device_name, buf.pointer) ?
+							AE_OK : AE_NOT_FOUND;
+		acpi_os_free(buf.pointer);
+	} else if (node->type == ACPI_IORT_NODE_PCI_ROOT_COMPLEX) {
+		struct acpi_iort_root_complex *pci_rc;
+		struct pci_bus *bus;
+
+		bus = to_pci_bus(dev);
+		pci_rc = (struct acpi_iort_root_complex *)node->node_data;
+
+		/*
+		 * It is assumed that PCI segment numbers maps one-to-one
+		 * with root complexes. Each segment number can represent only
+		 * one root complex.
+		 */
+		status = pci_rc->pci_segment_number == pci_domain_nr(bus) ?
+							AE_OK : AE_NOT_FOUND;
+	}
+out:
+	return status;
+}
+
+static int iort_id_map(struct acpi_iort_id_mapping *map, u8 type, u32 rid_in,
+		       u32 *rid_out)
+{
+	/* Single mapping does not care for input id */
+	if (map->flags & ACPI_IORT_ID_SINGLE_MAPPING) {
+		if (type == ACPI_IORT_NODE_NAMED_COMPONENT ||
+		    type == ACPI_IORT_NODE_PCI_ROOT_COMPLEX) {
+			*rid_out = map->output_base;
+			return 0;
+		}
+
+		pr_warn(FW_BUG "[map %p] SINGLE MAPPING flag not allowed for node type %d, skipping ID map\n",
+			map, type);
+		return -ENXIO;
+	}
+
+	if (rid_in < map->input_base ||
+	    (rid_in >= map->input_base + map->id_count))
+		return -ENXIO;
+
+	*rid_out = map->output_base + (rid_in - map->input_base);
+	return 0;
+}
+
+static
+struct acpi_iort_node *iort_node_get_id(struct acpi_iort_node *node,
+					u32 *id_out, int index)
+{
+	struct acpi_iort_node *parent;
+	struct acpi_iort_id_mapping *map;
+
+	if (!node->mapping_offset || !node->mapping_count ||
+				     index >= node->mapping_count)
+		return NULL;
+
+	map = ACPI_ADD_PTR(struct acpi_iort_id_mapping, node,
+			   node->mapping_offset + index * sizeof(*map));
+
+	/* Firmware bug! */
+	if (!map->output_reference) {
+		pr_err(FW_BUG "[node %p type %d] ID map has NULL parent reference\n",
+		       node, node->type);
+		return NULL;
+	}
+
+	parent = ACPI_ADD_PTR(struct acpi_iort_node, iort_table,
+			       map->output_reference);
+
+	if (map->flags & ACPI_IORT_ID_SINGLE_MAPPING) {
+		if (node->type == ACPI_IORT_NODE_NAMED_COMPONENT ||
+		    node->type == ACPI_IORT_NODE_PCI_ROOT_COMPLEX) {
+			*id_out = map->output_base;
+			return parent;
+		}
+	}
+
+	return NULL;
+}
+
+static struct acpi_iort_node *iort_node_map_id(struct acpi_iort_node *node,
+					       u32 id_in, u32 *id_out,
+					       u8 type_mask)
+{
+	u32 id = id_in;
+
+	/* Parse the ID mapping tree to find specified node type */
+	while (node) {
+		struct acpi_iort_id_mapping *map;
+		int i;
+
+		if (IORT_TYPE_MASK(node->type) & type_mask) {
+			if (id_out)
+				*id_out = id;
+			return node;
+		}
+
+		if (!node->mapping_offset || !node->mapping_count)
+			goto fail_map;
+
+		map = ACPI_ADD_PTR(struct acpi_iort_id_mapping, node,
+				   node->mapping_offset);
+
+		/* Firmware bug! */
+		if (!map->output_reference) {
+			pr_err(FW_BUG "[node %p type %d] ID map has NULL parent reference\n",
+			       node, node->type);
+			goto fail_map;
+		}
+
+		/* Do the ID translation */
+		for (i = 0; i < node->mapping_count; i++, map++) {
+			if (!iort_id_map(map, node->type, id, &id))
+				break;
+		}
+
+		if (i == node->mapping_count)
+			goto fail_map;
+
+		node = ACPI_ADD_PTR(struct acpi_iort_node, iort_table,
+				    map->output_reference);
+	}
+
+fail_map:
+	/* Map input ID to output ID unchanged on mapping failure */
+	if (id_out)
+		*id_out = id_in;
+
+	return NULL;
+}
+
+static
+struct acpi_iort_node *iort_node_map_platform_id(struct acpi_iort_node *node,
+						 u32 *id_out, u8 type_mask,
+						 int index)
+{
+	struct acpi_iort_node *parent;
+	u32 id;
+
+	/* step 1: retrieve the initial dev id */
+	parent = iort_node_get_id(node, &id, index);
+	if (!parent)
+		return NULL;
+
+	/*
+	 * optional step 2: map the initial dev id if its parent is not
+	 * the target type we want, map it again for the use cases such
+	 * as NC (named component) -> SMMU -> ITS. If the type is matched,
+	 * return the initial dev id and its parent pointer directly.
+	 */
+	if (!(IORT_TYPE_MASK(parent->type) & type_mask))
+		parent = iort_node_map_id(parent, id, id_out, type_mask);
+	else
+		if (id_out)
+			*id_out = id;
+
+	return parent;
+}
+
+static struct acpi_iort_node *iort_find_dev_node(struct device *dev)
+{
+	struct pci_bus *pbus;
+
+	if (!dev_is_pci(dev))
+		return iort_scan_node(ACPI_IORT_NODE_NAMED_COMPONENT,
+				      iort_match_node_callback, dev);
+
+	/* Find a PCI root bus */
+	pbus = to_pci_dev(dev)->bus;
+	while (!pci_is_root_bus(pbus))
+		pbus = pbus->parent;
+
+	return iort_scan_node(ACPI_IORT_NODE_PCI_ROOT_COMPLEX,
+			      iort_match_node_callback, &pbus->dev);
+}
+
+/**
+ * iort_msi_map_rid() - Map a MSI requester ID for a device
+ * @dev: The device for which the mapping is to be done.
+ * @req_id: The device requester ID.
+ *
+ * Returns: mapped MSI RID on success, input requester ID otherwise
+ */
+u32 iort_msi_map_rid(struct device *dev, u32 req_id)
+{
+	struct acpi_iort_node *node;
+	u32 dev_id;
+
+	node = iort_find_dev_node(dev);
+	if (!node)
+		return req_id;
+
+	iort_node_map_id(node, req_id, &dev_id, IORT_MSI_TYPE);
+	return dev_id;
+}
+
+/**
+ * iort_pmsi_get_dev_id() - Get the device id for a device
+ * @dev: The device for which the mapping is to be done.
+ * @dev_id: The device ID found.
+ *
+ * Returns: 0 for successful find a dev id, -ENODEV on error
+ */
+int iort_pmsi_get_dev_id(struct device *dev, u32 *dev_id)
+{
+	int i;
+	struct acpi_iort_node *node;
+
+	node = iort_find_dev_node(dev);
+	if (!node)
+		return -ENODEV;
+
+	for (i = 0; i < node->mapping_count; i++) {
+		if (iort_node_map_platform_id(node, dev_id, IORT_MSI_TYPE, i))
+			return 0;
+	}
+
+	return -ENODEV;
+}
+
+/**
+ * iort_dev_find_its_id() - Find the ITS identifier for a device
+ * @dev: The device.
+ * @req_id: Device's requester ID
+ * @idx: Index of the ITS identifier list.
+ * @its_id: ITS identifier.
+ *
+ * Returns: 0 on success, appropriate error value otherwise
+ */
+static int iort_dev_find_its_id(struct device *dev, u32 req_id,
+				unsigned int idx, int *its_id)
+{
+	struct acpi_iort_its_group *its;
+	struct acpi_iort_node *node;
+
+	node = iort_find_dev_node(dev);
+	if (!node)
+		return -ENXIO;
+
+	node = iort_node_map_id(node, req_id, NULL, IORT_MSI_TYPE);
+	if (!node)
+		return -ENXIO;
+
+	/* Move to ITS specific data */
+	its = (struct acpi_iort_its_group *)node->node_data;
+	if (idx > its->its_count) {
+		dev_err(dev, "requested ITS ID index [%d] is greater than available [%d]\n",
+			idx, its->its_count);
+		return -ENXIO;
+	}
+
+	*its_id = its->identifiers[idx];
+	return 0;
+}
+
+/**
+ * iort_get_device_domain() - Find MSI domain related to a device
+ * @dev: The device.
+ * @req_id: Requester ID for the device.
+ *
+ * Returns: the MSI domain for this device, NULL otherwise
+ */
+struct irq_domain *iort_get_device_domain(struct device *dev, u32 req_id)
+{
+	struct fwnode_handle *handle;
+	int its_id;
+
+	if (iort_dev_find_its_id(dev, req_id, 0, &its_id))
+		return NULL;
+
+	handle = iort_find_domain_token(its_id);
+	if (!handle)
+		return NULL;
+
+	return irq_find_matching_fwnode(handle, DOMAIN_BUS_PCI_MSI);
+}
+
+/**
+ * iort_get_platform_device_domain() - Find MSI domain related to a
+ * platform device
+ * @dev: the dev pointer associated with the platform device
+ *
+ * Returns: the MSI domain for this device, NULL otherwise
+ */
+static struct irq_domain *iort_get_platform_device_domain(struct device *dev)
+{
+	struct acpi_iort_node *node, *msi_parent;
+	struct fwnode_handle *iort_fwnode;
+	struct acpi_iort_its_group *its;
+	int i;
+
+	/* find its associated iort node */
+	node = iort_scan_node(ACPI_IORT_NODE_NAMED_COMPONENT,
+			      iort_match_node_callback, dev);
+	if (!node)
+		return NULL;
+
+	/* then find its msi parent node */
+	for (i = 0; i < node->mapping_count; i++) {
+		msi_parent = iort_node_map_platform_id(node, NULL,
+						       IORT_MSI_TYPE, i);
+		if (msi_parent)
+			break;
+	}
+
+	if (!msi_parent)
+		return NULL;
+
+	/* Move to ITS specific data */
+	its = (struct acpi_iort_its_group *)msi_parent->node_data;
+
+	iort_fwnode = iort_find_domain_token(its->identifiers[0]);
+	if (!iort_fwnode)
+		return NULL;
+
+	return irq_find_matching_fwnode(iort_fwnode, DOMAIN_BUS_PLATFORM_MSI);
+}
+
+void acpi_configure_pmsi_domain(struct device *dev)
+{
+	struct irq_domain *msi_domain;
+
+	msi_domain = iort_get_platform_device_domain(dev);
+	if (msi_domain)
+		dev_set_msi_domain(dev, msi_domain);
+}
+
+static int __maybe_unused __get_pci_rid(struct pci_dev *pdev, u16 alias,
+					void *data)
+{
+	u32 *rid = data;
+
+	*rid = alias;
+	return 0;
+}
+
+static int arm_smmu_iort_xlate(struct device *dev, u32 streamid,
+			       struct fwnode_handle *fwnode,
+			       const struct iommu_ops *ops)
+{
+	int ret = iommu_fwspec_init(dev, fwnode, ops);
+
+	if (!ret)
+		ret = iommu_fwspec_add_ids(dev, &streamid, 1);
+
+	return ret;
+}
+
+static inline bool iort_iommu_driver_enabled(u8 type)
+{
+	switch (type) {
+	case ACPI_IORT_NODE_SMMU_V3:
+		return IS_BUILTIN(CONFIG_ARM_SMMU_V3);
+	case ACPI_IORT_NODE_SMMU:
+		return IS_BUILTIN(CONFIG_ARM_SMMU);
+	default:
+		pr_warn("IORT node type %u does not describe an SMMU\n", type);
+		return false;
+	}
+}
+
+#ifdef CONFIG_IOMMU_API
+static inline
+const struct iommu_ops *iort_fwspec_iommu_ops(struct iommu_fwspec *fwspec)
+{
+	return (fwspec && fwspec->ops) ? fwspec->ops : NULL;
+}
+
+static inline
+int iort_add_device_replay(const struct iommu_ops *ops, struct device *dev)
+{
+	int err = 0;
+
+	if (ops->add_device && dev->bus && !dev->iommu_group)
+		err = ops->add_device(dev);
+
+	return err;
+}
+#else
+static inline
+const struct iommu_ops *iort_fwspec_iommu_ops(struct iommu_fwspec *fwspec)
+{ return NULL; }
+static inline
+int iort_add_device_replay(const struct iommu_ops *ops, struct device *dev)
+{ return 0; }
+#endif
+
+static int iort_iommu_xlate(struct device *dev, struct acpi_iort_node *node,
+			    u32 streamid)
+{
+	const struct iommu_ops *ops;
+	struct fwnode_handle *iort_fwnode;
+
+	if (!node)
+		return -ENODEV;
+
+	iort_fwnode = iort_get_fwnode(node);
+	if (!iort_fwnode)
+		return -ENODEV;
+
+	/*
+	 * If the ops look-up fails, this means that either
+	 * the SMMU drivers have not been probed yet or that
+	 * the SMMU drivers are not built in the kernel;
+	 * Depending on whether the SMMU drivers are built-in
+	 * in the kernel or not, defer the IOMMU configuration
+	 * or just abort it.
+	 */
+	ops = iommu_ops_from_fwnode(iort_fwnode);
+	if (!ops)
+		return iort_iommu_driver_enabled(node->type) ?
+		       -EPROBE_DEFER : -ENODEV;
+
+	return arm_smmu_iort_xlate(dev, streamid, iort_fwnode, ops);
+}
+
+struct iort_pci_alias_info {
+	struct device *dev;
+	struct acpi_iort_node *node;
+};
+
+static int iort_pci_iommu_init(struct pci_dev *pdev, u16 alias, void *data)
+{
+	struct iort_pci_alias_info *info = data;
+	struct acpi_iort_node *parent;
+	u32 streamid;
+
+	parent = iort_node_map_id(info->node, alias, &streamid,
+				  IORT_IOMMU_TYPE);
+	return iort_iommu_xlate(info->dev, parent, streamid);
+}
+
+static int nc_dma_get_range(struct device *dev, u64 *size)
+{
+	struct acpi_iort_node *node;
+	struct acpi_iort_named_component *ncomp;
+
+	node = iort_scan_node(ACPI_IORT_NODE_NAMED_COMPONENT,
+			      iort_match_node_callback, dev);
+	if (!node)
+		return -ENODEV;
+
+	ncomp = (struct acpi_iort_named_component *)node->node_data;
+
+	*size = ncomp->memory_address_limit >= 64 ? U64_MAX :
+			1ULL<<ncomp->memory_address_limit;
+
+	return 0;
+}
+
+/**
+ * iort_dma_setup() - Set-up device DMA parameters.
+ *
+ * @dev: device to configure
+ * @dma_addr: device DMA address result pointer
+ * @size: DMA range size result pointer
+ */
+void iort_dma_setup(struct device *dev, u64 *dma_addr, u64 *dma_size)
+{
+	u64 mask, dmaaddr = 0, size = 0, offset = 0;
+	int ret, msb;
+
+	/*
+	 * Set default coherent_dma_mask to 32 bit.  Drivers are expected to
+	 * setup the correct supported mask.
+	 */
+	if (!dev->coherent_dma_mask)
+		dev->coherent_dma_mask = DMA_BIT_MASK(32);
+
+	/*
+	 * Set it to coherent_dma_mask by default if the architecture
+	 * code has not set it.
+	 */
+	if (!dev->dma_mask)
+		dev->dma_mask = &dev->coherent_dma_mask;
+
+	size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1);
+
+	if (dev_is_pci(dev))
+		ret = acpi_dma_get_range(dev, &dmaaddr, &offset, &size);
+	else
+		ret = nc_dma_get_range(dev, &size);
+
+	if (!ret) {
+		msb = fls64(dmaaddr + size - 1);
+		/*
+		 * Round-up to the power-of-two mask or set
+		 * the mask to the whole 64-bit address space
+		 * in case the DMA region covers the full
+		 * memory window.
+		 */
+		mask = msb == 64 ? U64_MAX : (1ULL << msb) - 1;
+		/*
+		 * Limit coherent and dma mask based on size
+		 * retrieved from firmware.
+		 */
+		dev->coherent_dma_mask = mask;
+		*dev->dma_mask = mask;
+	}
+
+	*dma_addr = dmaaddr;
+	*dma_size = size;
+
+	dev->dma_pfn_offset = PFN_DOWN(offset);
+	dev_dbg(dev, "dma_pfn_offset(%#08llx)\n", offset);
+}
+
+/**
+ * iort_iommu_configure - Set-up IOMMU configuration for a device.
+ *
+ * @dev: device to configure
+ *
+ * Returns: iommu_ops pointer on configuration success
+ *          NULL on configuration failure
+ */
+const struct iommu_ops *iort_iommu_configure(struct device *dev)
+{
+	struct acpi_iort_node *node, *parent;
+	const struct iommu_ops *ops;
+	u32 streamid = 0;
+	int err = -ENODEV;
+
+	/*
+	 * If we already translated the fwspec there
+	 * is nothing left to do, return the iommu_ops.
+	 */
+	ops = iort_fwspec_iommu_ops(dev->iommu_fwspec);
+	if (ops)
+		return ops;
+
+	if (dev_is_pci(dev)) {
+		struct pci_bus *bus = to_pci_dev(dev)->bus;
+		struct iort_pci_alias_info info = { .dev = dev };
+
+		node = iort_scan_node(ACPI_IORT_NODE_PCI_ROOT_COMPLEX,
+				      iort_match_node_callback, &bus->dev);
+		if (!node)
+			return NULL;
+
+		info.node = node;
+		err = pci_for_each_dma_alias(to_pci_dev(dev),
+					     iort_pci_iommu_init, &info);
+	} else {
+		int i = 0;
+
+		node = iort_scan_node(ACPI_IORT_NODE_NAMED_COMPONENT,
+				      iort_match_node_callback, dev);
+		if (!node)
+			return NULL;
+
+		do {
+			parent = iort_node_map_platform_id(node, &streamid,
+							   IORT_IOMMU_TYPE,
+							   i++);
+
+			if (parent)
+				err = iort_iommu_xlate(dev, parent, streamid);
+		} while (parent && !err);
+	}
+
+	/*
+	 * If we have reason to believe the IOMMU driver missed the initial
+	 * add_device callback for dev, replay it to get things in order.
+	 */
+	if (!err) {
+		ops = iort_fwspec_iommu_ops(dev->iommu_fwspec);
+		err = iort_add_device_replay(ops, dev);
+	}
+
+	/* Ignore all other errors apart from EPROBE_DEFER */
+	if (err == -EPROBE_DEFER) {
+		ops = ERR_PTR(err);
+	} else if (err) {
+		dev_dbg(dev, "Adding to IOMMU failed: %d\n", err);
+		ops = NULL;
+	}
+
+	return ops;
+}
+
+static void __init acpi_iort_register_irq(int hwirq, const char *name,
+					  int trigger,
+					  struct resource *res)
+{
+	int irq = acpi_register_gsi(NULL, hwirq, trigger,
+				    ACPI_ACTIVE_HIGH);
+
+	if (irq <= 0) {
+		pr_err("could not register gsi hwirq %d name [%s]\n", hwirq,
+								      name);
+		return;
+	}
+
+	res->start = irq;
+	res->end = irq;
+	res->flags = IORESOURCE_IRQ;
+	res->name = name;
+}
+
+static int __init arm_smmu_v3_count_resources(struct acpi_iort_node *node)
+{
+	struct acpi_iort_smmu_v3 *smmu;
+	/* Always present mem resource */
+	int num_res = 1;
+
+	/* Retrieve SMMUv3 specific data */
+	smmu = (struct acpi_iort_smmu_v3 *)node->node_data;
+
+	if (smmu->event_gsiv)
+		num_res++;
+
+	if (smmu->pri_gsiv)
+		num_res++;
+
+	if (smmu->gerr_gsiv)
+		num_res++;
+
+	if (smmu->sync_gsiv)
+		num_res++;
+
+	return num_res;
+}
+
+static bool arm_smmu_v3_is_combined_irq(struct acpi_iort_smmu_v3 *smmu)
+{
+	/*
+	 * Cavium ThunderX2 implementation doesn't not support unique
+	 * irq line. Use single irq line for all the SMMUv3 interrupts.
+	 */
+	if (smmu->model != ACPI_IORT_SMMU_V3_CAVIUM_CN99XX)
+		return false;
+
+	/*
+	 * ThunderX2 doesn't support MSIs from the SMMU, so we're checking
+	 * SPI numbers here.
+	 */
+	return smmu->event_gsiv == smmu->pri_gsiv &&
+	       smmu->event_gsiv == smmu->gerr_gsiv &&
+	       smmu->event_gsiv == smmu->sync_gsiv;
+}
+
+static unsigned long arm_smmu_v3_resource_size(struct acpi_iort_smmu_v3 *smmu)
+{
+	/*
+	 * Override the size, for Cavium ThunderX2 implementation
+	 * which doesn't support the page 1 SMMU register space.
+	 */
+	if (smmu->model == ACPI_IORT_SMMU_V3_CAVIUM_CN99XX)
+		return SZ_64K;
+
+	return SZ_128K;
+}
+
+static void __init arm_smmu_v3_init_resources(struct resource *res,
+					      struct acpi_iort_node *node)
+{
+	struct acpi_iort_smmu_v3 *smmu;
+	int num_res = 0;
+
+	/* Retrieve SMMUv3 specific data */
+	smmu = (struct acpi_iort_smmu_v3 *)node->node_data;
+
+	res[num_res].start = smmu->base_address;
+	res[num_res].end = smmu->base_address +
+				arm_smmu_v3_resource_size(smmu) - 1;
+	res[num_res].flags = IORESOURCE_MEM;
+
+	num_res++;
+	if (arm_smmu_v3_is_combined_irq(smmu)) {
+		if (smmu->event_gsiv)
+			acpi_iort_register_irq(smmu->event_gsiv, "combined",
+					       ACPI_EDGE_SENSITIVE,
+					       &res[num_res++]);
+	} else {
+
+		if (smmu->event_gsiv)
+			acpi_iort_register_irq(smmu->event_gsiv, "eventq",
+					       ACPI_EDGE_SENSITIVE,
+					       &res[num_res++]);
+
+		if (smmu->pri_gsiv)
+			acpi_iort_register_irq(smmu->pri_gsiv, "priq",
+					       ACPI_EDGE_SENSITIVE,
+					       &res[num_res++]);
+
+		if (smmu->gerr_gsiv)
+			acpi_iort_register_irq(smmu->gerr_gsiv, "gerror",
+					       ACPI_EDGE_SENSITIVE,
+					       &res[num_res++]);
+
+		if (smmu->sync_gsiv)
+			acpi_iort_register_irq(smmu->sync_gsiv, "cmdq-sync",
+					       ACPI_EDGE_SENSITIVE,
+					       &res[num_res++]);
+	}
+}
+
+static bool __init arm_smmu_v3_is_coherent(struct acpi_iort_node *node)
+{
+	struct acpi_iort_smmu_v3 *smmu;
+
+	/* Retrieve SMMUv3 specific data */
+	smmu = (struct acpi_iort_smmu_v3 *)node->node_data;
+
+	return smmu->flags & ACPI_IORT_SMMU_V3_COHACC_OVERRIDE;
+}
+
+#if defined(CONFIG_ACPI_NUMA) && defined(ACPI_IORT_SMMU_V3_PXM_VALID)
+/*
+ * set numa proximity domain for smmuv3 device
+ */
+static void  __init arm_smmu_v3_set_proximity(struct device *dev,
+					      struct acpi_iort_node *node)
+{
+	struct acpi_iort_smmu_v3 *smmu;
+
+	smmu = (struct acpi_iort_smmu_v3 *)node->node_data;
+	if (smmu->flags & ACPI_IORT_SMMU_V3_PXM_VALID) {
+		set_dev_node(dev, acpi_map_pxm_to_node(smmu->pxm));
+		pr_info("SMMU-v3[%llx] Mapped to Proximity domain %d\n",
+			smmu->base_address,
+			smmu->pxm);
+	}
+}
+#else
+#define arm_smmu_v3_set_proximity NULL
+#endif
+
+static int __init arm_smmu_count_resources(struct acpi_iort_node *node)
+{
+	struct acpi_iort_smmu *smmu;
+
+	/* Retrieve SMMU specific data */
+	smmu = (struct acpi_iort_smmu *)node->node_data;
+
+	/*
+	 * Only consider the global fault interrupt and ignore the
+	 * configuration access interrupt.
+	 *
+	 * MMIO address and global fault interrupt resources are always
+	 * present so add them to the context interrupt count as a static
+	 * value.
+	 */
+	return smmu->context_interrupt_count + 2;
+}
+
+static void __init arm_smmu_init_resources(struct resource *res,
+					   struct acpi_iort_node *node)
+{
+	struct acpi_iort_smmu *smmu;
+	int i, hw_irq, trigger, num_res = 0;
+	u64 *ctx_irq, *glb_irq;
+
+	/* Retrieve SMMU specific data */
+	smmu = (struct acpi_iort_smmu *)node->node_data;
+
+	res[num_res].start = smmu->base_address;
+	res[num_res].end = smmu->base_address + smmu->span - 1;
+	res[num_res].flags = IORESOURCE_MEM;
+	num_res++;
+
+	glb_irq = ACPI_ADD_PTR(u64, node, smmu->global_interrupt_offset);
+	/* Global IRQs */
+	hw_irq = IORT_IRQ_MASK(glb_irq[0]);
+	trigger = IORT_IRQ_TRIGGER_MASK(glb_irq[0]);
+
+	acpi_iort_register_irq(hw_irq, "arm-smmu-global", trigger,
+				     &res[num_res++]);
+
+	/* Context IRQs */
+	ctx_irq = ACPI_ADD_PTR(u64, node, smmu->context_interrupt_offset);
+	for (i = 0; i < smmu->context_interrupt_count; i++) {
+		hw_irq = IORT_IRQ_MASK(ctx_irq[i]);
+		trigger = IORT_IRQ_TRIGGER_MASK(ctx_irq[i]);
+
+		acpi_iort_register_irq(hw_irq, "arm-smmu-context", trigger,
+				       &res[num_res++]);
+	}
+}
+
+static bool __init arm_smmu_is_coherent(struct acpi_iort_node *node)
+{
+	struct acpi_iort_smmu *smmu;
+
+	/* Retrieve SMMU specific data */
+	smmu = (struct acpi_iort_smmu *)node->node_data;
+
+	return smmu->flags & ACPI_IORT_SMMU_COHERENT_WALK;
+}
+
+struct iort_iommu_config {
+	const char *name;
+	int (*iommu_init)(struct acpi_iort_node *node);
+	bool (*iommu_is_coherent)(struct acpi_iort_node *node);
+	int (*iommu_count_resources)(struct acpi_iort_node *node);
+	void (*iommu_init_resources)(struct resource *res,
+				     struct acpi_iort_node *node);
+	void (*iommu_set_proximity)(struct device *dev,
+				    struct acpi_iort_node *node);
+};
+
+static const struct iort_iommu_config iort_arm_smmu_v3_cfg __initconst = {
+	.name = "arm-smmu-v3",
+	.iommu_is_coherent = arm_smmu_v3_is_coherent,
+	.iommu_count_resources = arm_smmu_v3_count_resources,
+	.iommu_init_resources = arm_smmu_v3_init_resources,
+	.iommu_set_proximity = arm_smmu_v3_set_proximity,
+};
+
+static const struct iort_iommu_config iort_arm_smmu_cfg __initconst = {
+	.name = "arm-smmu",
+	.iommu_is_coherent = arm_smmu_is_coherent,
+	.iommu_count_resources = arm_smmu_count_resources,
+	.iommu_init_resources = arm_smmu_init_resources
+};
+
+static __init
+const struct iort_iommu_config *iort_get_iommu_cfg(struct acpi_iort_node *node)
+{
+	switch (node->type) {
+	case ACPI_IORT_NODE_SMMU_V3:
+		return &iort_arm_smmu_v3_cfg;
+	case ACPI_IORT_NODE_SMMU:
+		return &iort_arm_smmu_cfg;
+	default:
+		return NULL;
+	}
+}
+
+/**
+ * iort_add_smmu_platform_device() - Allocate a platform device for SMMU
+ * @node: Pointer to SMMU ACPI IORT node
+ *
+ * Returns: 0 on success, <0 failure
+ */
+static int __init iort_add_smmu_platform_device(struct acpi_iort_node *node)
+{
+	struct fwnode_handle *fwnode;
+	struct platform_device *pdev;
+	struct resource *r;
+	enum dev_dma_attr attr;
+	int ret, count;
+	const struct iort_iommu_config *ops = iort_get_iommu_cfg(node);
+
+	if (!ops)
+		return -ENODEV;
+
+	pdev = platform_device_alloc(ops->name, PLATFORM_DEVID_AUTO);
+	if (!pdev)
+		return -ENOMEM;
+
+	if (ops->iommu_set_proximity)
+		ops->iommu_set_proximity(&pdev->dev, node);
+
+	count = ops->iommu_count_resources(node);
+
+	r = kcalloc(count, sizeof(*r), GFP_KERNEL);
+	if (!r) {
+		ret = -ENOMEM;
+		goto dev_put;
+	}
+
+	ops->iommu_init_resources(r, node);
+
+	ret = platform_device_add_resources(pdev, r, count);
+	/*
+	 * Resources are duplicated in platform_device_add_resources,
+	 * free their allocated memory
+	 */
+	kfree(r);
+
+	if (ret)
+		goto dev_put;
+
+	/*
+	 * Add a copy of IORT node pointer to platform_data to
+	 * be used to retrieve IORT data information.
+	 */
+	ret = platform_device_add_data(pdev, &node, sizeof(node));
+	if (ret)
+		goto dev_put;
+
+	/*
+	 * We expect the dma masks to be equivalent for
+	 * all SMMUs set-ups
+	 */
+	pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
+
+	fwnode = iort_get_fwnode(node);
+
+	if (!fwnode) {
+		ret = -ENODEV;
+		goto dev_put;
+	}
+
+	pdev->dev.fwnode = fwnode;
+
+	attr = ops->iommu_is_coherent(node) ?
+			     DEV_DMA_COHERENT : DEV_DMA_NON_COHERENT;
+
+	/* Configure DMA for the page table walker */
+	acpi_dma_configure(&pdev->dev, attr);
+
+	ret = platform_device_add(pdev);
+	if (ret)
+		goto dma_deconfigure;
+
+	return 0;
+
+dma_deconfigure:
+	acpi_dma_deconfigure(&pdev->dev);
+dev_put:
+	platform_device_put(pdev);
+
+	return ret;
+}
+
+static bool __init iort_enable_acs(struct acpi_iort_node *iort_node)
+{
+	if (iort_node->type == ACPI_IORT_NODE_PCI_ROOT_COMPLEX) {
+		struct acpi_iort_node *parent;
+		struct acpi_iort_id_mapping *map;
+		int i;
+
+		map = ACPI_ADD_PTR(struct acpi_iort_id_mapping, iort_node,
+				   iort_node->mapping_offset);
+
+		for (i = 0; i < iort_node->mapping_count; i++, map++) {
+			if (!map->output_reference)
+				continue;
+
+			parent = ACPI_ADD_PTR(struct acpi_iort_node,
+					iort_table,  map->output_reference);
+			/*
+			 * If we detect a RC->SMMU mapping, make sure
+			 * we enable ACS on the system.
+			 */
+			if ((parent->type == ACPI_IORT_NODE_SMMU) ||
+				(parent->type == ACPI_IORT_NODE_SMMU_V3)) {
+				pci_request_acs();
+				return true;
+			}
+		}
+	}
+
+	return false;
+}
+
+static void __init iort_init_platform_devices(void)
+{
+	struct acpi_iort_node *iort_node, *iort_end;
+	struct acpi_table_iort *iort;
+	struct fwnode_handle *fwnode;
+	int i, ret;
+	bool acs_enabled = false;
+
+	/*
+	 * iort_table and iort both point to the start of IORT table, but
+	 * have different struct types
+	 */
+	iort = (struct acpi_table_iort *)iort_table;
+
+	/* Get the first IORT node */
+	iort_node = ACPI_ADD_PTR(struct acpi_iort_node, iort,
+				 iort->node_offset);
+	iort_end = ACPI_ADD_PTR(struct acpi_iort_node, iort,
+				iort_table->length);
+
+	for (i = 0; i < iort->node_count; i++) {
+		if (iort_node >= iort_end) {
+			pr_err("iort node pointer overflows, bad table\n");
+			return;
+		}
+
+		if (!acs_enabled)
+			acs_enabled = iort_enable_acs(iort_node);
+
+		if ((iort_node->type == ACPI_IORT_NODE_SMMU) ||
+			(iort_node->type == ACPI_IORT_NODE_SMMU_V3)) {
+
+			fwnode = acpi_alloc_fwnode_static();
+			if (!fwnode)
+				return;
+
+			iort_set_fwnode(iort_node, fwnode);
+
+			ret = iort_add_smmu_platform_device(iort_node);
+			if (ret) {
+				iort_delete_fwnode(iort_node);
+				acpi_free_fwnode_static(fwnode);
+				return;
+			}
+		}
+
+		iort_node = ACPI_ADD_PTR(struct acpi_iort_node, iort_node,
+					 iort_node->length);
+	}
+}
+
+void __init acpi_iort_init(void)
+{
+	acpi_status status;
+
+	status = acpi_get_table(ACPI_SIG_IORT, 0, &iort_table);
+	if (ACPI_FAILURE(status)) {
+		if (status != AE_NOT_FOUND) {
+			const char *msg = acpi_format_exception(status);
+
+			pr_err("Failed to get table, %s\n", msg);
+		}
+
+		return;
+	}
+
+	iort_init_platform_devices();
+}
diff --git a/xen/include/acpi/acpi_iort.h b/xen/include/acpi/acpi_iort.h
new file mode 100644
index 0000000000..8d3f0bf803
--- /dev/null
+++ b/xen/include/acpi/acpi_iort.h
@@ -0,0 +1,57 @@ 
+/*
+ * Copyright (C) 2016, Semihalf
+ *	Author: Tomasz Nowicki <tn@semihalf.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ */
+
+#ifndef __ACPI_IORT_H__
+#define __ACPI_IORT_H__
+
+#include <linux/acpi.h>
+#include <linux/fwnode.h>
+#include <linux/irqdomain.h>
+
+#define IORT_IRQ_MASK(irq)		(irq & 0xffffffffULL)
+#define IORT_IRQ_TRIGGER_MASK(irq)	((irq >> 32) & 0xffffffffULL)
+
+int iort_register_domain_token(int trans_id, struct fwnode_handle *fw_node);
+void iort_deregister_domain_token(int trans_id);
+struct fwnode_handle *iort_find_domain_token(int trans_id);
+#ifdef CONFIG_ACPI_IORT
+void acpi_iort_init(void);
+u32 iort_msi_map_rid(struct device *dev, u32 req_id);
+struct irq_domain *iort_get_device_domain(struct device *dev, u32 req_id);
+void acpi_configure_pmsi_domain(struct device *dev);
+int iort_pmsi_get_dev_id(struct device *dev, u32 *dev_id);
+/* IOMMU interface */
+void iort_dma_setup(struct device *dev, u64 *dma_addr, u64 *size);
+const struct iommu_ops *iort_iommu_configure(struct device *dev);
+#else
+static inline void acpi_iort_init(void) { }
+static inline u32 iort_msi_map_rid(struct device *dev, u32 req_id)
+{ return req_id; }
+static inline struct irq_domain *iort_get_device_domain(struct device *dev,
+							u32 req_id)
+{ return NULL; }
+static inline void acpi_configure_pmsi_domain(struct device *dev) { }
+/* IOMMU interface */
+static inline void iort_dma_setup(struct device *dev, u64 *dma_addr,
+				  u64 *size) { }
+static inline
+const struct iommu_ops *iort_iommu_configure(struct device *dev)
+{ return NULL; }
+#endif
+
+#endif /* __ACPI_IORT_H__ */