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-rw-r--r--drivers/of/irq.c579
1 files changed, 579 insertions, 0 deletions
diff --git a/drivers/of/irq.c b/drivers/of/irq.c
new file mode 100644
index 000000000..1a7980692
--- /dev/null
+++ b/drivers/of/irq.c
@@ -0,0 +1,579 @@
+/*
+ * 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;
+
+ 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) {
+ res = -EINVAL;
+ goto out;
+ }
+ intsize = be32_to_cpu(*tmp);
+
+ pr_debug(" intsize=%d intlen=%d\n", intsize, intlen);
+
+ /* Check index */
+ if ((index + 1) * intsize > intlen) {
+ res = -EINVAL;
+ 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);
+ }
+}