Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 751 insertions, 0 deletions

diff --git a/drivers/of/irq.c b/drivers/of/irq.c
new file mode 100644
index 0000000000..174900072c
--- /dev/null
+++ b/drivers/of/irq.c
@@ -0,0 +1,751 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ *  Derived from arch/i386/kernel/irq.c
+ *    Copyright (C) 1992 Linus Torvalds
+ *  Adapted from arch/i386 by Gary Thomas
+ *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *  Updated and modified by Cort Dougan <cort@fsmlabs.com>
+ *    Copyright (C) 1996-2001 Cort Dougan
+ *  Adapted for Power Macintosh by Paul Mackerras
+ *    Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au)
+ *
+ * This file contains the code used to make IRQ descriptions in the
+ * device tree to actual irq numbers on an interrupt controller
+ * driver.
+ */
+
+#define pr_fmt(fmt)	"OF: " fmt
+
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+
+/**
+ * irq_of_parse_and_map - Parse and map an interrupt into linux virq space
+ * @dev: Device node of the device whose interrupt is to be mapped
+ * @index: Index of the interrupt to map
+ *
+ * This function is a wrapper that chains of_irq_parse_one() and
+ * irq_create_of_mapping() to make things easier to callers
+ */
+unsigned int irq_of_parse_and_map(struct device_node *dev, int index)
+{
+	struct of_phandle_args oirq;
+
+	if (of_irq_parse_one(dev, index, &oirq))
+		return 0;
+
+	return irq_create_of_mapping(&oirq);
+}
+EXPORT_SYMBOL_GPL(irq_of_parse_and_map);
+
+/**
+ * of_irq_find_parent - Given a device node, find its interrupt parent node
+ * @child: pointer to device node
+ *
+ * Return: A pointer to the interrupt parent node, or NULL if the interrupt
+ * parent could not be determined.
+ */
+struct device_node *of_irq_find_parent(struct device_node *child)
+{
+	struct device_node *p;
+	phandle parent;
+
+	if (!of_node_get(child))
+		return NULL;
+
+	do {
+		if (of_property_read_u32(child, "interrupt-parent", &parent)) {
+			p = of_get_parent(child);
+		} else	{
+			if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
+				p = of_node_get(of_irq_dflt_pic);
+			else
+				p = of_find_node_by_phandle(parent);
+		}
+		of_node_put(child);
+		child = p;
+	} while (p && of_get_property(p, "#interrupt-cells", NULL) == NULL);
+
+	return p;
+}
+EXPORT_SYMBOL_GPL(of_irq_find_parent);
+
+/*
+ * These interrupt controllers abuse interrupt-map for unspeakable
+ * reasons and rely on the core code to *ignore* it (the drivers do
+ * their own parsing of the property).
+ *
+ * If you think of adding to the list for something *new*, think
+ * again. There is a high chance that you will be sent back to the
+ * drawing board.
+ */
+static const char * const of_irq_imap_abusers[] = {
+	"CBEA,platform-spider-pic",
+	"sti,platform-spider-pic",
+	"realtek,rtl-intc",
+	"fsl,ls1021a-extirq",
+	"fsl,ls1043a-extirq",
+	"fsl,ls1088a-extirq",
+	"renesas,rza1-irqc",
+	NULL,
+};
+
+/**
+ * of_irq_parse_raw - Low level interrupt tree parsing
+ * @addr:	address specifier (start of "reg" property of the device) in be32 format
+ * @out_irq:	structure of_phandle_args updated by this function
+ *
+ * This function is a low-level interrupt tree walking function. It
+ * can be used to do a partial walk with synthetized reg and interrupts
+ * properties, for example when resolving PCI interrupts when no device
+ * node exist for the parent. It takes an interrupt specifier structure as
+ * input, walks the tree looking for any interrupt-map properties, translates
+ * the specifier for each map, and then returns the translated map.
+ *
+ * Return: 0 on success and a negative number on error
+ */
+int of_irq_parse_raw(const __be32 *addr, struct of_phandle_args *out_irq)
+{
+	struct device_node *ipar, *tnode, *old = NULL, *newpar = NULL;
+	__be32 initial_match_array[MAX_PHANDLE_ARGS];
+	const __be32 *match_array = initial_match_array;
+	const __be32 *tmp, *imap, *imask, dummy_imask[] = { [0 ... MAX_PHANDLE_ARGS] = cpu_to_be32(~0) };
+	u32 intsize = 1, addrsize, newintsize = 0, newaddrsize = 0;
+	int imaplen, match, i, rc = -EINVAL;
+
+#ifdef DEBUG
+	of_print_phandle_args("of_irq_parse_raw: ", out_irq);
+#endif
+
+	ipar = of_node_get(out_irq->np);
+
+	/* First get the #interrupt-cells property of the current cursor
+	 * that tells us how to interpret the passed-in intspec. If there
+	 * is none, we are nice and just walk up the tree
+	 */
+	do {
+		if (!of_property_read_u32(ipar, "#interrupt-cells", &intsize))
+			break;
+		tnode = ipar;
+		ipar = of_irq_find_parent(ipar);
+		of_node_put(tnode);
+	} while (ipar);
+	if (ipar == NULL) {
+		pr_debug(" -> no parent found !\n");
+		goto fail;
+	}
+
+	pr_debug("of_irq_parse_raw: ipar=%pOF, size=%d\n", ipar, intsize);
+
+	if (out_irq->args_count != intsize)
+		goto fail;
+
+	/* Look for this #address-cells. We have to implement the old linux
+	 * trick of looking for the parent here as some device-trees rely on it
+	 */
+	old = of_node_get(ipar);
+	do {
+		tmp = of_get_property(old, "#address-cells", NULL);
+		tnode = of_get_parent(old);
+		of_node_put(old);
+		old = tnode;
+	} while (old && tmp == NULL);
+	of_node_put(old);
+	old = NULL;
+	addrsize = (tmp == NULL) ? 2 : be32_to_cpu(*tmp);
+
+	pr_debug(" -> addrsize=%d\n", addrsize);
+
+	/* Range check so that the temporary buffer doesn't overflow */
+	if (WARN_ON(addrsize + intsize > MAX_PHANDLE_ARGS)) {
+		rc = -EFAULT;
+		goto fail;
+	}
+
+	/* Precalculate the match array - this simplifies match loop */
+	for (i = 0; i < addrsize; i++)
+		initial_match_array[i] = addr ? addr[i] : 0;
+	for (i = 0; i < intsize; i++)
+		initial_match_array[addrsize + i] = cpu_to_be32(out_irq->args[i]);
+
+	/* Now start the actual "proper" walk of the interrupt tree */
+	while (ipar != NULL) {
+		/*
+		 * Now check if cursor is an interrupt-controller and
+		 * if it is then we are done, unless there is an
+		 * interrupt-map which takes precedence except on one
+		 * of these broken platforms that want to parse
+		 * interrupt-map themselves for $reason.
+		 */
+		bool intc = of_property_read_bool(ipar, "interrupt-controller");
+
+		imap = of_get_property(ipar, "interrupt-map", &imaplen);
+		if (intc &&
+		    (!imap || of_device_compatible_match(ipar, of_irq_imap_abusers))) {
+			pr_debug(" -> got it !\n");
+			return 0;
+		}
+
+		/*
+		 * interrupt-map parsing does not work without a reg
+		 * property when #address-cells != 0
+		 */
+		if (addrsize && !addr) {
+			pr_debug(" -> no reg passed in when needed !\n");
+			goto fail;
+		}
+
+		/* No interrupt map, check for an interrupt parent */
+		if (imap == NULL) {
+			pr_debug(" -> no map, getting parent\n");
+			newpar = of_irq_find_parent(ipar);
+			goto skiplevel;
+		}
+		imaplen /= sizeof(u32);
+
+		/* Look for a mask */
+		imask = of_get_property(ipar, "interrupt-map-mask", NULL);
+		if (!imask)
+			imask = dummy_imask;
+
+		/* Parse interrupt-map */
+		match = 0;
+		while (imaplen > (addrsize + intsize + 1) && !match) {
+			/* Compare specifiers */
+			match = 1;
+			for (i = 0; i < (addrsize + intsize); i++, imaplen--)
+				match &= !((match_array[i] ^ *imap++) & imask[i]);
+
+			pr_debug(" -> match=%d (imaplen=%d)\n", match, imaplen);
+
+			/* Get the interrupt parent */
+			if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
+				newpar = of_node_get(of_irq_dflt_pic);
+			else
+				newpar = of_find_node_by_phandle(be32_to_cpup(imap));
+			imap++;
+			--imaplen;
+
+			/* Check if not found */
+			if (newpar == NULL) {
+				pr_debug(" -> imap parent not found !\n");
+				goto fail;
+			}
+
+			if (!of_device_is_available(newpar))
+				match = 0;
+
+			/* Get #interrupt-cells and #address-cells of new
+			 * parent
+			 */
+			if (of_property_read_u32(newpar, "#interrupt-cells",
+						 &newintsize)) {
+				pr_debug(" -> parent lacks #interrupt-cells!\n");
+				goto fail;
+			}
+			if (of_property_read_u32(newpar, "#address-cells",
+						 &newaddrsize))
+				newaddrsize = 0;
+
+			pr_debug(" -> newintsize=%d, newaddrsize=%d\n",
+			    newintsize, newaddrsize);
+
+			/* Check for malformed properties */
+			if (WARN_ON(newaddrsize + newintsize > MAX_PHANDLE_ARGS)
+			    || (imaplen < (newaddrsize + newintsize))) {
+				rc = -EFAULT;
+				goto fail;
+			}
+
+			imap += newaddrsize + newintsize;
+			imaplen -= newaddrsize + newintsize;
+
+			pr_debug(" -> imaplen=%d\n", imaplen);
+		}
+		if (!match) {
+			if (intc) {
+				/*
+				 * The PASEMI Nemo is a known offender, so
+				 * let's only warn for anyone else.
+				 */
+				WARN(!IS_ENABLED(CONFIG_PPC_PASEMI),
+				     "%pOF interrupt-map failed, using interrupt-controller\n",
+				     ipar);
+				return 0;
+			}
+
+			goto fail;
+		}
+
+		/*
+		 * Successfully parsed an interrupt-map translation; copy new
+		 * interrupt specifier into the out_irq structure
+		 */
+		match_array = imap - newaddrsize - newintsize;
+		for (i = 0; i < newintsize; i++)
+			out_irq->args[i] = be32_to_cpup(imap - newintsize + i);
+		out_irq->args_count = intsize = newintsize;
+		addrsize = newaddrsize;
+
+		if (ipar == newpar) {
+			pr_debug("%pOF interrupt-map entry to self\n", ipar);
+			return 0;
+		}
+
+	skiplevel:
+		/* Iterate again with new parent */
+		out_irq->np = newpar;
+		pr_debug(" -> new parent: %pOF\n", newpar);
+		of_node_put(ipar);
+		ipar = newpar;
+		newpar = NULL;
+	}
+	rc = -ENOENT; /* No interrupt-map found */
+
+ fail:
+	of_node_put(ipar);
+	of_node_put(newpar);
+
+	return rc;
+}
+EXPORT_SYMBOL_GPL(of_irq_parse_raw);
+
+/**
+ * of_irq_parse_one - Resolve an interrupt for a device
+ * @device: the device whose interrupt is to be resolved
+ * @index: index of the interrupt to resolve
+ * @out_irq: structure of_phandle_args filled by this function
+ *
+ * This function resolves an interrupt for a node by walking the interrupt tree,
+ * finding which interrupt controller node it is attached to, and returning the
+ * interrupt specifier that can be used to retrieve a Linux IRQ number.
+ */
+int of_irq_parse_one(struct device_node *device, int index, struct of_phandle_args *out_irq)
+{
+	struct device_node *p;
+	const __be32 *addr;
+	u32 intsize;
+	int i, res;
+
+	pr_debug("of_irq_parse_one: dev=%pOF, index=%d\n", device, index);
+
+	/* OldWorld mac stuff is "special", handle out of line */
+	if (of_irq_workarounds & OF_IMAP_OLDWORLD_MAC)
+		return of_irq_parse_oldworld(device, index, out_irq);
+
+	/* Get the reg property (if any) */
+	addr = of_get_property(device, "reg", NULL);
+
+	/* Try the new-style interrupts-extended first */
+	res = of_parse_phandle_with_args(device, "interrupts-extended",
+					"#interrupt-cells", index, out_irq);
+	if (!res)
+		return of_irq_parse_raw(addr, out_irq);
+
+	/* Look for the interrupt parent. */
+	p = of_irq_find_parent(device);
+	if (p == NULL)
+		return -EINVAL;
+
+	/* Get size of interrupt specifier */
+	if (of_property_read_u32(p, "#interrupt-cells", &intsize)) {
+		res = -EINVAL;
+		goto out;
+	}
+
+	pr_debug(" parent=%pOF, intsize=%d\n", p, intsize);
+
+	/* Copy intspec into irq structure */
+	out_irq->np = p;
+	out_irq->args_count = intsize;
+	for (i = 0; i < intsize; i++) {
+		res = of_property_read_u32_index(device, "interrupts",
+						 (index * intsize) + i,
+						 out_irq->args + i);
+		if (res)
+			goto out;
+	}
+
+	pr_debug(" intspec=%d\n", *out_irq->args);
+
+
+	/* Check if there are any interrupt-map translations to process */
+	res = of_irq_parse_raw(addr, out_irq);
+ out:
+	of_node_put(p);
+	return res;
+}
+EXPORT_SYMBOL_GPL(of_irq_parse_one);
+
+/**
+ * of_irq_to_resource - Decode a node's IRQ and return it as a resource
+ * @dev: pointer to device tree node
+ * @index: zero-based index of the irq
+ * @r: pointer to resource structure to return result into.
+ */
+int of_irq_to_resource(struct device_node *dev, int index, struct resource *r)
+{
+	int irq = of_irq_get(dev, index);
+
+	if (irq < 0)
+		return irq;
+
+	/* Only dereference the resource if both the
+	 * resource and the irq are valid. */
+	if (r && irq) {
+		const char *name = NULL;
+
+		memset(r, 0, sizeof(*r));
+		/*
+		 * Get optional "interrupt-names" property to add a name
+		 * to the resource.
+		 */
+		of_property_read_string_index(dev, "interrupt-names", index,
+					      &name);
+
+		r->start = r->end = irq;
+		r->flags = IORESOURCE_IRQ | irqd_get_trigger_type(irq_get_irq_data(irq));
+		r->name = name ? name : of_node_full_name(dev);
+	}
+
+	return irq;
+}
+EXPORT_SYMBOL_GPL(of_irq_to_resource);
+
+/**
+ * of_irq_get - Decode a node's IRQ and return it as a Linux IRQ number
+ * @dev: pointer to device tree node
+ * @index: zero-based index of the IRQ
+ *
+ * Return: Linux IRQ number on success, or 0 on the IRQ mapping failure, or
+ * -EPROBE_DEFER if the IRQ domain is not yet created, or error code in case
+ * of any other failure.
+ */
+int of_irq_get(struct device_node *dev, int index)
+{
+	int rc;
+	struct of_phandle_args oirq;
+	struct irq_domain *domain;
+
+	rc = of_irq_parse_one(dev, index, &oirq);
+	if (rc)
+		return rc;
+
+	domain = irq_find_host(oirq.np);
+	if (!domain) {
+		rc = -EPROBE_DEFER;
+		goto out;
+	}
+
+	rc = irq_create_of_mapping(&oirq);
+out:
+	of_node_put(oirq.np);
+
+	return rc;
+}
+EXPORT_SYMBOL_GPL(of_irq_get);
+
+/**
+ * of_irq_get_byname - Decode a node's IRQ and return it as a Linux IRQ number
+ * @dev: pointer to device tree node
+ * @name: IRQ name
+ *
+ * Return: Linux IRQ number on success, or 0 on the IRQ mapping failure, or
+ * -EPROBE_DEFER if the IRQ domain is not yet created, or error code in case
+ * of any other failure.
+ */
+int of_irq_get_byname(struct device_node *dev, const char *name)
+{
+	int index;
+
+	if (unlikely(!name))
+		return -EINVAL;
+
+	index = of_property_match_string(dev, "interrupt-names", name);
+	if (index < 0)
+		return index;
+
+	return of_irq_get(dev, index);
+}
+EXPORT_SYMBOL_GPL(of_irq_get_byname);
+
+/**
+ * of_irq_count - Count the number of IRQs a node uses
+ * @dev: pointer to device tree node
+ */
+int of_irq_count(struct device_node *dev)
+{
+	struct of_phandle_args irq;
+	int nr = 0;
+
+	while (of_irq_parse_one(dev, nr, &irq) == 0)
+		nr++;
+
+	return nr;
+}
+
+/**
+ * of_irq_to_resource_table - Fill in resource table with node's IRQ info
+ * @dev: pointer to device tree node
+ * @res: array of resources to fill in
+ * @nr_irqs: the number of IRQs (and upper bound for num of @res elements)
+ *
+ * Return: The size of the filled in table (up to @nr_irqs).
+ */
+int of_irq_to_resource_table(struct device_node *dev, struct resource *res,
+		int nr_irqs)
+{
+	int i;
+
+	for (i = 0; i < nr_irqs; i++, res++)
+		if (of_irq_to_resource(dev, i, res) <= 0)
+			break;
+
+	return i;
+}
+EXPORT_SYMBOL_GPL(of_irq_to_resource_table);
+
+struct of_intc_desc {
+	struct list_head	list;
+	of_irq_init_cb_t	irq_init_cb;
+	struct device_node	*dev;
+	struct device_node	*interrupt_parent;
+};
+
+/**
+ * of_irq_init - Scan and init matching interrupt controllers in DT
+ * @matches: 0 terminated array of nodes to match and init function to call
+ *
+ * This function scans the device tree for matching interrupt controller nodes,
+ * and calls their initialization functions in order with parents first.
+ */
+void __init of_irq_init(const struct of_device_id *matches)
+{
+	const struct of_device_id *match;
+	struct device_node *np, *parent = NULL;
+	struct of_intc_desc *desc, *temp_desc;
+	struct list_head intc_desc_list, intc_parent_list;
+
+	INIT_LIST_HEAD(&intc_desc_list);
+	INIT_LIST_HEAD(&intc_parent_list);
+
+	for_each_matching_node_and_match(np, matches, &match) {
+		if (!of_property_read_bool(np, "interrupt-controller") ||
+				!of_device_is_available(np))
+			continue;
+
+		if (WARN(!match->data, "of_irq_init: no init function for %s\n",
+			 match->compatible))
+			continue;
+
+		/*
+		 * Here, we allocate and populate an of_intc_desc with the node
+		 * pointer, interrupt-parent device_node etc.
+		 */
+		desc = kzalloc(sizeof(*desc), GFP_KERNEL);
+		if (!desc) {
+			of_node_put(np);
+			goto err;
+		}
+
+		desc->irq_init_cb = match->data;
+		desc->dev = of_node_get(np);
+		/*
+		 * interrupts-extended can reference multiple parent domains.
+		 * Arbitrarily pick the first one; assume any other parents
+		 * are the same distance away from the root irq controller.
+		 */
+		desc->interrupt_parent = of_parse_phandle(np, "interrupts-extended", 0);
+		if (!desc->interrupt_parent)
+			desc->interrupt_parent = of_irq_find_parent(np);
+		if (desc->interrupt_parent == np) {
+			of_node_put(desc->interrupt_parent);
+			desc->interrupt_parent = NULL;
+		}
+		list_add_tail(&desc->list, &intc_desc_list);
+	}
+
+	/*
+	 * The root irq controller is the one without an interrupt-parent.
+	 * That one goes first, followed by the controllers that reference it,
+	 * followed by the ones that reference the 2nd level controllers, etc.
+	 */
+	while (!list_empty(&intc_desc_list)) {
+		/*
+		 * Process all controllers with the current 'parent'.
+		 * First pass will be looking for NULL as the parent.
+		 * The assumption is that NULL parent means a root controller.
+		 */
+		list_for_each_entry_safe(desc, temp_desc, &intc_desc_list, list) {
+			int ret;
+
+			if (desc->interrupt_parent != parent)
+				continue;
+
+			list_del(&desc->list);
+
+			of_node_set_flag(desc->dev, OF_POPULATED);
+
+			pr_debug("of_irq_init: init %pOF (%p), parent %p\n",
+				 desc->dev,
+				 desc->dev, desc->interrupt_parent);
+			ret = desc->irq_init_cb(desc->dev,
+						desc->interrupt_parent);
+			if (ret) {
+				pr_err("%s: Failed to init %pOF (%p), parent %p\n",
+				       __func__, desc->dev, desc->dev,
+				       desc->interrupt_parent);
+				of_node_clear_flag(desc->dev, OF_POPULATED);
+				kfree(desc);
+				continue;
+			}
+
+			/*
+			 * This one is now set up; add it to the parent list so
+			 * its children can get processed in a subsequent pass.
+			 */
+			list_add_tail(&desc->list, &intc_parent_list);
+		}
+
+		/* Get the next pending parent that might have children */
+		desc = list_first_entry_or_null(&intc_parent_list,
+						typeof(*desc), list);
+		if (!desc) {
+			pr_err("of_irq_init: children remain, but no parents\n");
+			break;
+		}
+		list_del(&desc->list);
+		parent = desc->dev;
+		kfree(desc);
+	}
+
+	list_for_each_entry_safe(desc, temp_desc, &intc_parent_list, list) {
+		list_del(&desc->list);
+		kfree(desc);
+	}
+err:
+	list_for_each_entry_safe(desc, temp_desc, &intc_desc_list, list) {
+		list_del(&desc->list);
+		of_node_put(desc->dev);
+		kfree(desc);
+	}
+}
+
+static u32 __of_msi_map_id(struct device *dev, struct device_node **np,
+			    u32 id_in)
+{
+	struct device *parent_dev;
+	u32 id_out = id_in;
+
+	/*
+	 * Walk up the device parent links looking for one with a
+	 * "msi-map" property.
+	 */
+	for (parent_dev = dev; parent_dev; parent_dev = parent_dev->parent)
+		if (!of_map_id(parent_dev->of_node, id_in, "msi-map",
+				"msi-map-mask", np, &id_out))
+			break;
+	return id_out;
+}
+
+/**
+ * of_msi_map_id - Map a MSI ID for a device.
+ * @dev: device for which the mapping is to be done.
+ * @msi_np: device node of the expected msi controller.
+ * @id_in: unmapped MSI ID for the device.
+ *
+ * Walk up the device hierarchy looking for devices with a "msi-map"
+ * property.  If found, apply the mapping to @id_in.
+ *
+ * Return: The mapped MSI ID.
+ */
+u32 of_msi_map_id(struct device *dev, struct device_node *msi_np, u32 id_in)
+{
+	return __of_msi_map_id(dev, &msi_np, id_in);
+}
+
+/**
+ * of_msi_map_get_device_domain - Use msi-map to find the relevant MSI domain
+ * @dev: device for which the mapping is to be done.
+ * @id: Device ID.
+ * @bus_token: Bus token
+ *
+ * Walk up the device hierarchy looking for devices with a "msi-map"
+ * property.
+ *
+ * Returns: the MSI domain for this device (or NULL on failure)
+ */
+struct irq_domain *of_msi_map_get_device_domain(struct device *dev, u32 id,
+						u32 bus_token)
+{
+	struct device_node *np = NULL;
+
+	__of_msi_map_id(dev, &np, id);
+	return irq_find_matching_host(np, bus_token);
+}
+
+/**
+ * of_msi_get_domain - Use msi-parent to find the relevant MSI domain
+ * @dev: device for which the domain is requested
+ * @np: device node for @dev
+ * @token: bus type for this domain
+ *
+ * Parse the msi-parent property (both the simple and the complex
+ * versions), and returns the corresponding MSI domain.
+ *
+ * Returns: the MSI domain for this device (or NULL on failure).
+ */
+struct irq_domain *of_msi_get_domain(struct device *dev,
+				     struct device_node *np,
+				     enum irq_domain_bus_token token)
+{
+	struct device_node *msi_np;
+	struct irq_domain *d;
+
+	/* Check for a single msi-parent property */
+	msi_np = of_parse_phandle(np, "msi-parent", 0);
+	if (msi_np && !of_property_read_bool(msi_np, "#msi-cells")) {
+		d = irq_find_matching_host(msi_np, token);
+		if (!d)
+			of_node_put(msi_np);
+		return d;
+	}
+
+	if (token == DOMAIN_BUS_PLATFORM_MSI) {
+		/* Check for the complex msi-parent version */
+		struct of_phandle_args args;
+		int index = 0;
+
+		while (!of_parse_phandle_with_args(np, "msi-parent",
+						   "#msi-cells",
+						   index, &args)) {
+			d = irq_find_matching_host(args.np, token);
+			if (d)
+				return d;
+
+			of_node_put(args.np);
+			index++;
+		}
+	}
+
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(of_msi_get_domain);
+
+/**
+ * of_msi_configure - Set the msi_domain field of a device
+ * @dev: device structure to associate with an MSI irq domain
+ * @np: device node for that device
+ */
+void of_msi_configure(struct device *dev, struct device_node *np)
+{
+	dev_set_msi_domain(dev,
+			   of_msi_get_domain(dev, np, DOMAIN_BUS_PLATFORM_MSI));
+}
+EXPORT_SYMBOL_GPL(of_msi_configure);