drivers/of/irq.c - kernel/msm-4.9 - Gitiles

 /*
  *  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 program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
  * as published by the Free Software Foundation; either version
  * 2 of the License, or (at your option) any later version.
  *
  * This file contains the code used to make IRQ descriptions in the
  * device tree to actual irq numbers on an interrupt controller
  * driver.
  */

 #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
  *
  * Returns 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;
 	const __be32 *parp;

 	if (!of_node_get(child))
 		return NULL;

 	do {
 		parp = of_get_property(child, "interrupt-parent", NULL);
 		if (parp == NULL)
 			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(be32_to_cpup(parp));
 		}
 		of_node_put(child);
 		child = p;
 	} while (p && of_get_property(p, "#interrupt-cells", NULL) == NULL);

 	return p;
 }

 /**
  * of_irq_parse_raw - Low level interrupt tree parsing
  * @parent:	the device interrupt parent
  * @addr:	address specifier (start of "reg" property of the device) in be32 format
  * @out_irq:	structure of_irq updated by this function
  *
  * Returns 0 on success and a negative number on error
  *
  * 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.
  */
 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] = ~0 };
 	u32 intsize = 1, addrsize, newintsize = 0, newaddrsize = 0;
 	int imaplen, match, i;

 #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 {
 		tmp = of_get_property(ipar, "#interrupt-cells", NULL);
 		if (tmp != NULL) {
 			intsize = be32_to_cpu(*tmp);
 			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=%s, size=%d\n", of_node_full_name(ipar), intsize);

 	if (out_irq->args_count != intsize)
 		return -EINVAL;

 	/* 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))
 		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
 		 */
 		if (of_get_property(ipar, "interrupt-controller", NULL) !=
 				NULL) {
 			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;
 		}

 		/* Now look for an interrupt-map */
 		imap = of_get_property(ipar, "interrupt-map", &imaplen);
 		/* 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
 			 */
 			tmp = of_get_property(newpar, "#interrupt-cells", NULL);
 			if (tmp == NULL) {
 				pr_debug(" -> parent lacks #interrupt-cells!\n");
 				goto fail;
 			}
 			newintsize = be32_to_cpu(*tmp);
 			tmp = of_get_property(newpar, "#address-cells", NULL);
 			newaddrsize = (tmp == NULL) ? 0 : be32_to_cpu(*tmp);

 			pr_debug(" -> newintsize=%d, newaddrsize=%d\n",
 			    newintsize, newaddrsize);

 			/* Check for malformed properties */
 			if (WARN_ON(newaddrsize + newintsize > MAX_PHANDLE_ARGS))
 				goto fail;
 			if (imaplen < (newaddrsize + newintsize))
 				goto fail;

 			imap += newaddrsize + newintsize;
 			imaplen -= newaddrsize + newintsize;

 			pr_debug(" -> imaplen=%d\n", imaplen);
 		}
 		if (!match)
 			goto fail;

 		/*
 		 * Successfully parsed an interrrupt-map translation; copy new
 		 * interrupt specifier into the out_irq structure
 		 */
 		out_irq->np = newpar;

 		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;

 	skiplevel:
 		/* Iterate again with new parent */
 		pr_debug(" -> new parent: %s\n", of_node_full_name(newpar));
 		of_node_put(ipar);
 		ipar = newpar;
 		newpar = NULL;
 	}
  fail:
 	of_node_put(ipar);
 	of_node_put(newpar);

 	return -EINVAL;
 }
 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_irq 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 *intspec, *tmp, *addr;
 	u32 intsize, intlen;
 	int i, res = -EINVAL;

 	pr_debug("of_irq_parse_one: dev=%s, index=%d\n", of_node_full_name(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);

 	/* Get the interrupts property */
 	intspec = of_get_property(device, "interrupts", &intlen);
 	if (intspec == NULL)
 		return -EINVAL;

 	intlen /= sizeof(*intspec);

 	pr_debug(" intspec=%d intlen=%d\n", be32_to_cpup(intspec), intlen);

 	/* Look for the interrupt parent. */
 	p = of_irq_find_parent(device);
 	if (p == NULL)
 		return -EINVAL;

 	/* Get size of interrupt specifier */
 	tmp = of_get_property(p, "#interrupt-cells", NULL);
 	if (tmp == NULL)
 		goto out;
 	intsize = be32_to_cpu(*tmp);

 	pr_debug(" intsize=%d intlen=%d\n", intsize, intlen);

 	/* Check index */
 	if ((index + 1) * intsize > intlen)
 		goto out;

 	/* Copy intspec into irq structure */
 	intspec += index * intsize;
 	out_irq->np = p;
 	out_irq->args_count = intsize;
 	for (i = 0; i < intsize; i++)
 		out_irq->args[i] = be32_to_cpup(intspec++);

 	/* 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 = irq_of_parse_and_map(dev, index);

 	/* 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
  *
  * Returns Linux irq number on success, or -EPROBE_DEFER if the irq domain
  * is not yet created.
  *
  */
 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)
 		return -EPROBE_DEFER;

 	return irq_create_of_mapping(&oirq);
 }
 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
  *
  * Returns Linux irq number on success, 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);
 }

 /**
  * 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)
  *
  * Returns 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))
 			break;

 	return i;
 }
 EXPORT_SYMBOL_GPL(of_irq_to_resource_table);

 struct intc_desc {
 	struct list_head	list;
 	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)
 {
 	struct device_node *np, *parent = NULL;
 	struct 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(np, matches) {
 		if (!of_find_property(np, "interrupt-controller", NULL) ||
 				!of_device_is_available(np))
 			continue;
 		/*
 		 * Here, we allocate and populate an intc_desc with the node
 		 * pointer, interrupt-parent device_node etc.
 		 */
 		desc = kzalloc(sizeof(*desc), GFP_KERNEL);
 		if (WARN_ON(!desc))
 			goto err;

 		desc->dev = np;
 		desc->interrupt_parent = of_irq_find_parent(np);
 		if (desc->interrupt_parent == np)
 			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) {
 			const struct of_device_id *match;
 			int ret;
 			of_irq_init_cb_t irq_init_cb;

 			if (desc->interrupt_parent != parent)
 				continue;

 			list_del(&desc->list);
 			match = of_match_node(matches, desc->dev);
 			if (WARN(!match->data,
 			    "of_irq_init: no init function for %s\n",
 			    match->compatible)) {
 				kfree(desc);
 				continue;
 			}

 			pr_debug("of_irq_init: init %s @ %p, parent %p\n",
 				 match->compatible,
 				 desc->dev, desc->interrupt_parent);
 			irq_init_cb = (of_irq_init_cb_t)match->data;
 			ret = irq_init_cb(desc->dev, desc->interrupt_parent);
 			if (ret) {
 				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);
 		kfree(desc);
 	}
 }
	/*
	* 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 program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License
	* as published by the Free Software Foundation; either version
	* 2 of the License, or (at your option) any later version.
	*
	* This file contains the code used to make IRQ descriptions in the
	* device tree to actual irq numbers on an interrupt controller
	* driver.
	*/

	#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
	*
	* Returns 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;
	const __be32 *parp;

	if (!of_node_get(child))
	return NULL;

	do {
	parp = of_get_property(child, "interrupt-parent", NULL);
	if (parp == NULL)
	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(be32_to_cpup(parp));
	}
	of_node_put(child);
	child = p;
	} while (p && of_get_property(p, "#interrupt-cells", NULL) == NULL);

	return p;
	}

	/**
	* of_irq_parse_raw - Low level interrupt tree parsing
	* @parent: the device interrupt parent
	* @addr: address specifier (start of "reg" property of the device) in be32 format
	* @out_irq: structure of_irq updated by this function
	*
	* Returns 0 on success and a negative number on error
	*
	* 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.
	*/
	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] = ~0 };
	u32 intsize = 1, addrsize, newintsize = 0, newaddrsize = 0;
	int imaplen, match, i;

	#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 {
	tmp = of_get_property(ipar, "#interrupt-cells", NULL);
	if (tmp != NULL) {
	intsize = be32_to_cpu(*tmp);
	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=%s, size=%d\n", of_node_full_name(ipar), intsize);

	if (out_irq->args_count != intsize)
	return -EINVAL;

	/* 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))
	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
	*/
	if (of_get_property(ipar, "interrupt-controller", NULL) !=
	NULL) {
	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;
	}

	/* Now look for an interrupt-map */
	imap = of_get_property(ipar, "interrupt-map", &imaplen);
	/* 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
	*/
	tmp = of_get_property(newpar, "#interrupt-cells", NULL);
	if (tmp == NULL) {
	pr_debug(" -> parent lacks #interrupt-cells!\n");
	goto fail;
	}
	newintsize = be32_to_cpu(*tmp);
	tmp = of_get_property(newpar, "#address-cells", NULL);
	newaddrsize = (tmp == NULL) ? 0 : be32_to_cpu(*tmp);

	pr_debug(" -> newintsize=%d, newaddrsize=%d\n",
	newintsize, newaddrsize);

	/* Check for malformed properties */
	if (WARN_ON(newaddrsize + newintsize > MAX_PHANDLE_ARGS))
	goto fail;
	if (imaplen < (newaddrsize + newintsize))
	goto fail;

	imap += newaddrsize + newintsize;
	imaplen -= newaddrsize + newintsize;

	pr_debug(" -> imaplen=%d\n", imaplen);
	}
	if (!match)
	goto fail;

	/*
	* Successfully parsed an interrrupt-map translation; copy new
	* interrupt specifier into the out_irq structure
	*/
	out_irq->np = newpar;

	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;

	skiplevel:
	/* Iterate again with new parent */
	pr_debug(" -> new parent: %s\n", of_node_full_name(newpar));
	of_node_put(ipar);
	ipar = newpar;
	newpar = NULL;
	}
	fail:
	of_node_put(ipar);
	of_node_put(newpar);

	return -EINVAL;
	}
	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_irq 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 intspec, tmp, *addr;
	u32 intsize, intlen;
	int i, res = -EINVAL;

	pr_debug("of_irq_parse_one: dev=%s, index=%d\n", of_node_full_name(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);

	/* Get the interrupts property */
	intspec = of_get_property(device, "interrupts", &intlen);
	if (intspec == NULL)
	return -EINVAL;

	intlen /= sizeof(*intspec);

	pr_debug(" intspec=%d intlen=%d\n", be32_to_cpup(intspec), intlen);

	/* Look for the interrupt parent. */
	p = of_irq_find_parent(device);
	if (p == NULL)
	return -EINVAL;

	/* Get size of interrupt specifier */
	tmp = of_get_property(p, "#interrupt-cells", NULL);
	if (tmp == NULL)
	goto out;
	intsize = be32_to_cpu(*tmp);

	pr_debug(" intsize=%d intlen=%d\n", intsize, intlen);

	/* Check index */
	if ((index + 1) * intsize > intlen)
	goto out;

	/* Copy intspec into irq structure */
	intspec += index * intsize;
	out_irq->np = p;
	out_irq->args_count = intsize;
	for (i = 0; i < intsize; i++)
	out_irq->args[i] = be32_to_cpup(intspec++);

	/* 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 = irq_of_parse_and_map(dev, index);

	/* 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
	*
	* Returns Linux irq number on success, or -EPROBE_DEFER if the irq domain
	* is not yet created.
	*
	*/
	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)
	return -EPROBE_DEFER;

	return irq_create_of_mapping(&oirq);
	}
	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
	*
	* Returns Linux irq number on success, 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);
	}

	/**
	* 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)
	*
	* Returns 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))
	break;

	return i;
	}
	EXPORT_SYMBOL_GPL(of_irq_to_resource_table);

	struct intc_desc {
	struct list_head list;
	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)
	{
	struct device_node np, parent = NULL;
	struct 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(np, matches) {
	if (!of_find_property(np, "interrupt-controller", NULL) \|\|
	!of_device_is_available(np))
	continue;
	/*
	* Here, we allocate and populate an intc_desc with the node
	* pointer, interrupt-parent device_node etc.
	*/
	desc = kzalloc(sizeof(*desc), GFP_KERNEL);
	if (WARN_ON(!desc))
	goto err;

	desc->dev = np;
	desc->interrupt_parent = of_irq_find_parent(np);
	if (desc->interrupt_parent == np)
	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) {
	const struct of_device_id *match;
	int ret;
	of_irq_init_cb_t irq_init_cb;

	if (desc->interrupt_parent != parent)
	continue;

	list_del(&desc->list);
	match = of_match_node(matches, desc->dev);
	if (WARN(!match->data,
	"of_irq_init: no init function for %s\n",
	match->compatible)) {
	kfree(desc);
	continue;
	}

	pr_debug("of_irq_init: init %s @ %p, parent %p\n",
	match->compatible,
	desc->dev, desc->interrupt_parent);
	irq_init_cb = (of_irq_init_cb_t)match->data;
	ret = irq_init_cb(desc->dev, desc->interrupt_parent);
	if (ret) {
	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);
	kfree(desc);
	}
	}