2 * Derived from arch/i386/kernel/irq.c
3 * Copyright (C) 1992 Linus Torvalds
4 * Adapted from arch/i386 by Gary Thomas
5 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
6 * Updated and modified by Cort Dougan <cort@fsmlabs.com>
7 * Copyright (C) 1996-2001 Cort Dougan
8 * Adapted for Power Macintosh by Paul Mackerras
9 * Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au)
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License
13 * as published by the Free Software Foundation; either version
14 * 2 of the License, or (at your option) any later version.
16 * This file contains the code used to make IRQ descriptions in the
17 * device tree to actual irq numbers on an interrupt controller
21 #include <linux/errno.h>
22 #include <linux/list.h>
23 #include <linux/module.h>
25 #include <linux/of_irq.h>
26 #include <linux/string.h>
27 #include <linux/slab.h>
30 * irq_of_parse_and_map - Parse and map an interrupt into linux virq space
31 * @dev: Device node of the device whose interrupt is to be mapped
32 * @index: Index of the interrupt to map
34 * This function is a wrapper that chains of_irq_parse_one() and
35 * irq_create_of_mapping() to make things easier to callers
37 unsigned int irq_of_parse_and_map(struct device_node *dev, int index)
39 struct of_phandle_args oirq;
41 if (of_irq_parse_one(dev, index, &oirq))
44 return irq_create_of_mapping(&oirq);
46 EXPORT_SYMBOL_GPL(irq_of_parse_and_map);
49 * of_irq_find_parent - Given a device node, find its interrupt parent node
50 * @child: pointer to device node
52 * Returns a pointer to the interrupt parent node, or NULL if the interrupt
53 * parent could not be determined.
55 struct device_node *of_irq_find_parent(struct device_node *child)
57 struct device_node *p;
60 if (!of_node_get(child))
64 parp = of_get_property(child, "interrupt-parent", NULL);
66 p = of_get_parent(child);
68 if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
69 p = of_node_get(of_irq_dflt_pic);
71 p = of_find_node_by_phandle(be32_to_cpup(parp));
75 } while (p && of_get_property(p, "#interrupt-cells", NULL) == NULL);
81 * of_irq_parse_raw - Low level interrupt tree parsing
82 * @parent: the device interrupt parent
83 * @addr: address specifier (start of "reg" property of the device) in be32 format
84 * @out_irq: structure of_irq updated by this function
86 * Returns 0 on success and a negative number on error
88 * This function is a low-level interrupt tree walking function. It
89 * can be used to do a partial walk with synthetized reg and interrupts
90 * properties, for example when resolving PCI interrupts when no device
91 * node exist for the parent. It takes an interrupt specifier structure as
92 * input, walks the tree looking for any interrupt-map properties, translates
93 * the specifier for each map, and then returns the translated map.
95 int of_irq_parse_raw(const __be32 *addr, struct of_phandle_args *out_irq)
97 struct device_node *ipar, *tnode, *old = NULL, *newpar = NULL;
98 __be32 initial_match_array[8];
99 const __be32 *match_array = initial_match_array;
100 const __be32 *tmp, *imap, *imask, dummy_imask[] = { ~0, ~0, ~0, ~0, ~0 };
101 u32 intsize = 1, addrsize, newintsize = 0, newaddrsize = 0;
102 int imaplen, match, i;
105 of_print_phandle_args("of_irq_parse_raw: ", out_irq);
108 ipar = of_node_get(out_irq->np);
110 /* First get the #interrupt-cells property of the current cursor
111 * that tells us how to interpret the passed-in intspec. If there
112 * is none, we are nice and just walk up the tree
115 tmp = of_get_property(ipar, "#interrupt-cells", NULL);
117 intsize = be32_to_cpu(*tmp);
121 ipar = of_irq_find_parent(ipar);
125 pr_debug(" -> no parent found !\n");
129 pr_debug("of_irq_parse_raw: ipar=%s, size=%d\n", of_node_full_name(ipar), intsize);
131 if (out_irq->args_count != intsize)
134 /* Look for this #address-cells. We have to implement the old linux
135 * trick of looking for the parent here as some device-trees rely on it
137 old = of_node_get(ipar);
139 tmp = of_get_property(old, "#address-cells", NULL);
140 tnode = of_get_parent(old);
143 } while (old && tmp == NULL);
146 addrsize = (tmp == NULL) ? 2 : be32_to_cpu(*tmp);
148 pr_debug(" -> addrsize=%d\n", addrsize);
150 /* If we were passed no "reg" property and we attempt to parse
151 * an interrupt-map, then #address-cells must be 0.
154 if (addr == NULL && addrsize != 0) {
155 pr_debug(" -> no reg passed in when needed !\n");
159 /* Precalculate the match array - this simplifies match loop */
160 for (i = 0; i < addrsize; i++)
161 initial_match_array[i] = addr[i];
162 for (i = 0; i < intsize; i++)
163 initial_match_array[addrsize + i] = cpu_to_be32(out_irq->args[i]);
165 /* Now start the actual "proper" walk of the interrupt tree */
166 while (ipar != NULL) {
167 /* Now check if cursor is an interrupt-controller and if it is
170 if (of_get_property(ipar, "interrupt-controller", NULL) !=
172 pr_debug(" -> got it !\n");
177 /* Now look for an interrupt-map */
178 imap = of_get_property(ipar, "interrupt-map", &imaplen);
179 /* No interrupt map, check for an interrupt parent */
181 pr_debug(" -> no map, getting parent\n");
182 newpar = of_irq_find_parent(ipar);
185 imaplen /= sizeof(u32);
187 /* Look for a mask */
188 imask = of_get_property(ipar, "interrupt-map-mask", NULL);
192 /* Parse interrupt-map */
194 while (imaplen > (addrsize + intsize + 1) && !match) {
195 /* Compare specifiers */
197 for (i = 0; i < (addrsize + intsize); i++, imaplen--)
198 match = !((match_array[i] ^ *imap++) & imask[i]);
200 pr_debug(" -> match=%d (imaplen=%d)\n", match, imaplen);
202 /* Get the interrupt parent */
203 if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
204 newpar = of_node_get(of_irq_dflt_pic);
206 newpar = of_find_node_by_phandle(be32_to_cpup(imap));
210 /* Check if not found */
211 if (newpar == NULL) {
212 pr_debug(" -> imap parent not found !\n");
216 /* Get #interrupt-cells and #address-cells of new
219 tmp = of_get_property(newpar, "#interrupt-cells", NULL);
221 pr_debug(" -> parent lacks #interrupt-cells!\n");
224 newintsize = be32_to_cpu(*tmp);
225 tmp = of_get_property(newpar, "#address-cells", NULL);
226 newaddrsize = (tmp == NULL) ? 0 : be32_to_cpu(*tmp);
228 pr_debug(" -> newintsize=%d, newaddrsize=%d\n",
229 newintsize, newaddrsize);
231 /* Check for malformed properties */
232 if (imaplen < (newaddrsize + newintsize))
235 imap += newaddrsize + newintsize;
236 imaplen -= newaddrsize + newintsize;
238 pr_debug(" -> imaplen=%d\n", imaplen);
244 * Successfully parsed an interrrupt-map translation; copy new
245 * interrupt specifier into the out_irq structure
247 of_node_put(out_irq->np);
248 out_irq->np = of_node_get(newpar);
250 match_array = imap - newaddrsize - newintsize;
251 for (i = 0; i < newintsize; i++)
252 out_irq->args[i] = be32_to_cpup(imap - newintsize + i);
253 out_irq->args_count = intsize = newintsize;
254 addrsize = newaddrsize;
257 /* Iterate again with new parent */
258 pr_debug(" -> new parent: %s\n", of_node_full_name(newpar));
265 of_node_put(out_irq->np);
270 EXPORT_SYMBOL_GPL(of_irq_parse_raw);
273 * of_irq_parse_one - Resolve an interrupt for a device
274 * @device: the device whose interrupt is to be resolved
275 * @index: index of the interrupt to resolve
276 * @out_irq: structure of_irq filled by this function
278 * This function resolves an interrupt for a node by walking the interrupt tree,
279 * finding which interrupt controller node it is attached to, and returning the
280 * interrupt specifier that can be used to retrieve a Linux IRQ number.
282 int of_irq_parse_one(struct device_node *device, int index, struct of_phandle_args *out_irq)
284 struct device_node *p;
285 const __be32 *intspec, *tmp, *addr;
287 int i, res = -EINVAL;
289 pr_debug("of_irq_parse_one: dev=%s, index=%d\n", of_node_full_name(device), index);
291 /* OldWorld mac stuff is "special", handle out of line */
292 if (of_irq_workarounds & OF_IMAP_OLDWORLD_MAC)
293 return of_irq_parse_oldworld(device, index, out_irq);
295 /* Get the interrupts property */
296 intspec = of_get_property(device, "interrupts", &intlen);
299 intlen /= sizeof(*intspec);
301 pr_debug(" intspec=%d intlen=%d\n", be32_to_cpup(intspec), intlen);
303 /* Get the reg property (if any) */
304 addr = of_get_property(device, "reg", NULL);
306 /* Look for the interrupt parent. */
307 p = of_irq_find_parent(device);
311 /* Get size of interrupt specifier */
312 tmp = of_get_property(p, "#interrupt-cells", NULL);
315 intsize = be32_to_cpu(*tmp);
317 pr_debug(" intsize=%d intlen=%d\n", intsize, intlen);
320 if ((index + 1) * intsize > intlen)
323 /* Copy intspec into irq structure */
324 intspec += index * intsize;
326 out_irq->args_count = intsize;
327 for (i = 0; i < intsize; i++)
328 out_irq->args[i] = be32_to_cpup(intspec++);
330 /* Check if there are any interrupt-map translations to process */
331 res = of_irq_parse_raw(addr, out_irq);
336 EXPORT_SYMBOL_GPL(of_irq_parse_one);
339 * of_irq_to_resource - Decode a node's IRQ and return it as a resource
340 * @dev: pointer to device tree node
341 * @index: zero-based index of the irq
342 * @r: pointer to resource structure to return result into.
344 int of_irq_to_resource(struct device_node *dev, int index, struct resource *r)
346 int irq = irq_of_parse_and_map(dev, index);
348 /* Only dereference the resource if both the
349 * resource and the irq are valid. */
351 const char *name = NULL;
353 memset(r, 0, sizeof(*r));
355 * Get optional "interrupts-names" property to add a name
358 of_property_read_string_index(dev, "interrupt-names", index,
361 r->start = r->end = irq;
362 r->flags = IORESOURCE_IRQ | irqd_get_trigger_type(irq_get_irq_data(irq));
363 r->name = name ? name : of_node_full_name(dev);
368 EXPORT_SYMBOL_GPL(of_irq_to_resource);
371 * of_irq_count - Count the number of IRQs a node uses
372 * @dev: pointer to device tree node
374 int of_irq_count(struct device_node *dev)
376 struct of_phandle_args irq;
379 while (of_irq_parse_one(dev, nr, &irq) == 0)
386 * of_irq_to_resource_table - Fill in resource table with node's IRQ info
387 * @dev: pointer to device tree node
388 * @res: array of resources to fill in
389 * @nr_irqs: the number of IRQs (and upper bound for num of @res elements)
391 * Returns the size of the filled in table (up to @nr_irqs).
393 int of_irq_to_resource_table(struct device_node *dev, struct resource *res,
398 for (i = 0; i < nr_irqs; i++, res++)
399 if (!of_irq_to_resource(dev, i, res))
404 EXPORT_SYMBOL_GPL(of_irq_to_resource_table);
407 struct list_head list;
408 struct device_node *dev;
409 struct device_node *interrupt_parent;
413 * of_irq_init - Scan and init matching interrupt controllers in DT
414 * @matches: 0 terminated array of nodes to match and init function to call
416 * This function scans the device tree for matching interrupt controller nodes,
417 * and calls their initialization functions in order with parents first.
419 void __init of_irq_init(const struct of_device_id *matches)
421 struct device_node *np, *parent = NULL;
422 struct intc_desc *desc, *temp_desc;
423 struct list_head intc_desc_list, intc_parent_list;
425 INIT_LIST_HEAD(&intc_desc_list);
426 INIT_LIST_HEAD(&intc_parent_list);
428 for_each_matching_node(np, matches) {
429 if (!of_find_property(np, "interrupt-controller", NULL))
432 * Here, we allocate and populate an intc_desc with the node
433 * pointer, interrupt-parent device_node etc.
435 desc = kzalloc(sizeof(*desc), GFP_KERNEL);
440 desc->interrupt_parent = of_irq_find_parent(np);
441 if (desc->interrupt_parent == np)
442 desc->interrupt_parent = NULL;
443 list_add_tail(&desc->list, &intc_desc_list);
447 * The root irq controller is the one without an interrupt-parent.
448 * That one goes first, followed by the controllers that reference it,
449 * followed by the ones that reference the 2nd level controllers, etc.
451 while (!list_empty(&intc_desc_list)) {
453 * Process all controllers with the current 'parent'.
454 * First pass will be looking for NULL as the parent.
455 * The assumption is that NULL parent means a root controller.
457 list_for_each_entry_safe(desc, temp_desc, &intc_desc_list, list) {
458 const struct of_device_id *match;
460 of_irq_init_cb_t irq_init_cb;
462 if (desc->interrupt_parent != parent)
465 list_del(&desc->list);
466 match = of_match_node(matches, desc->dev);
467 if (WARN(!match->data,
468 "of_irq_init: no init function for %s\n",
469 match->compatible)) {
474 pr_debug("of_irq_init: init %s @ %p, parent %p\n",
476 desc->dev, desc->interrupt_parent);
477 irq_init_cb = (of_irq_init_cb_t)match->data;
478 ret = irq_init_cb(desc->dev, desc->interrupt_parent);
485 * This one is now set up; add it to the parent list so
486 * its children can get processed in a subsequent pass.
488 list_add_tail(&desc->list, &intc_parent_list);
491 /* Get the next pending parent that might have children */
492 desc = list_first_entry_or_null(&intc_parent_list,
493 typeof(*desc), list);
495 pr_err("of_irq_init: children remain, but no parents\n");
498 list_del(&desc->list);
503 list_for_each_entry_safe(desc, temp_desc, &intc_parent_list, list) {
504 list_del(&desc->list);
508 list_for_each_entry_safe(desc, temp_desc, &intc_desc_list, list) {
509 list_del(&desc->list);