blob: 75b0d3cb7676d39458ad2f402c0bb255a779f6b5 [file] [log] [blame]
Grant Likelye3873442010-06-18 11:09:59 -06001/*
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)
10 *
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.
15 *
16 * This file contains the code used to make IRQ descriptions in the
17 * device tree to actual irq numbers on an interrupt controller
18 * driver.
19 */
20
21#include <linux/errno.h>
22#include <linux/module.h>
23#include <linux/of.h>
24#include <linux/of_irq.h>
25#include <linux/string.h>
26
Andres Salomon52f65372010-10-10 21:35:05 -060027/* For archs that don't support NO_IRQ (such as x86), provide a dummy value */
28#ifndef NO_IRQ
29#define NO_IRQ 0
30#endif
31
Grant Likelye3873442010-06-18 11:09:59 -060032/**
33 * irq_of_parse_and_map - Parse and map an interrupt into linux virq space
34 * @device: Device node of the device whose interrupt is to be mapped
35 * @index: Index of the interrupt to map
36 *
37 * This function is a wrapper that chains of_irq_map_one() and
38 * irq_create_of_mapping() to make things easier to callers
39 */
40unsigned int irq_of_parse_and_map(struct device_node *dev, int index)
41{
42 struct of_irq oirq;
43
44 if (of_irq_map_one(dev, index, &oirq))
45 return NO_IRQ;
46
47 return irq_create_of_mapping(oirq.controller, oirq.specifier,
48 oirq.size);
49}
50EXPORT_SYMBOL_GPL(irq_of_parse_and_map);
Grant Likely7dc2e112010-06-08 07:48:06 -060051
52/**
53 * of_irq_find_parent - Given a device node, find its interrupt parent node
54 * @child: pointer to device node
55 *
56 * Returns a pointer to the interrupt parent node, or NULL if the interrupt
57 * parent could not be determined.
58 */
59static struct device_node *of_irq_find_parent(struct device_node *child)
60{
61 struct device_node *p;
Grant Likely9a6b2e52010-07-23 01:48:25 -060062 const __be32 *parp;
Grant Likely7dc2e112010-06-08 07:48:06 -060063
64 if (!of_node_get(child))
65 return NULL;
66
67 do {
68 parp = of_get_property(child, "interrupt-parent", NULL);
69 if (parp == NULL)
70 p = of_get_parent(child);
71 else {
72 if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
73 p = of_node_get(of_irq_dflt_pic);
74 else
Grant Likely9a6b2e52010-07-23 01:48:25 -060075 p = of_find_node_by_phandle(be32_to_cpup(parp));
Grant Likely7dc2e112010-06-08 07:48:06 -060076 }
77 of_node_put(child);
78 child = p;
79 } while (p && of_get_property(p, "#interrupt-cells", NULL) == NULL);
80
81 return p;
82}
83
84/**
85 * of_irq_map_raw - Low level interrupt tree parsing
86 * @parent: the device interrupt parent
87 * @intspec: interrupt specifier ("interrupts" property of the device)
88 * @ointsize: size of the passed in interrupt specifier
89 * @addr: address specifier (start of "reg" property of the device)
90 * @out_irq: structure of_irq filled by this function
91 *
92 * Returns 0 on success and a negative number on error
93 *
94 * This function is a low-level interrupt tree walking function. It
95 * can be used to do a partial walk with synthetized reg and interrupts
96 * properties, for example when resolving PCI interrupts when no device
97 * node exist for the parent.
98 */
Grant Likelyd2f71832010-07-23 16:56:19 -060099int of_irq_map_raw(struct device_node *parent, const __be32 *intspec,
100 u32 ointsize, const __be32 *addr, struct of_irq *out_irq)
Grant Likely7dc2e112010-06-08 07:48:06 -0600101{
102 struct device_node *ipar, *tnode, *old = NULL, *newpar = NULL;
Rob Herringa7c194b2010-06-08 07:48:08 -0600103 const __be32 *tmp, *imap, *imask;
Grant Likely7dc2e112010-06-08 07:48:06 -0600104 u32 intsize = 1, addrsize, newintsize = 0, newaddrsize = 0;
105 int imaplen, match, i;
106
107 pr_debug("of_irq_map_raw: par=%s,intspec=[0x%08x 0x%08x...],ointsize=%d\n",
Grant Likelyd2f71832010-07-23 16:56:19 -0600108 parent->full_name, be32_to_cpup(intspec),
109 be32_to_cpup(intspec + 1), ointsize);
Grant Likely7dc2e112010-06-08 07:48:06 -0600110
111 ipar = of_node_get(parent);
112
113 /* First get the #interrupt-cells property of the current cursor
114 * that tells us how to interpret the passed-in intspec. If there
115 * is none, we are nice and just walk up the tree
116 */
117 do {
118 tmp = of_get_property(ipar, "#interrupt-cells", NULL);
119 if (tmp != NULL) {
Rob Herringa7c194b2010-06-08 07:48:08 -0600120 intsize = be32_to_cpu(*tmp);
Grant Likely7dc2e112010-06-08 07:48:06 -0600121 break;
122 }
123 tnode = ipar;
124 ipar = of_irq_find_parent(ipar);
125 of_node_put(tnode);
126 } while (ipar);
127 if (ipar == NULL) {
128 pr_debug(" -> no parent found !\n");
129 goto fail;
130 }
131
132 pr_debug("of_irq_map_raw: ipar=%s, size=%d\n", ipar->full_name, intsize);
133
134 if (ointsize != intsize)
135 return -EINVAL;
136
137 /* Look for this #address-cells. We have to implement the old linux
138 * trick of looking for the parent here as some device-trees rely on it
139 */
140 old = of_node_get(ipar);
141 do {
142 tmp = of_get_property(old, "#address-cells", NULL);
143 tnode = of_get_parent(old);
144 of_node_put(old);
145 old = tnode;
146 } while (old && tmp == NULL);
147 of_node_put(old);
148 old = NULL;
Rob Herringa7c194b2010-06-08 07:48:08 -0600149 addrsize = (tmp == NULL) ? 2 : be32_to_cpu(*tmp);
Grant Likely7dc2e112010-06-08 07:48:06 -0600150
151 pr_debug(" -> addrsize=%d\n", addrsize);
152
153 /* Now start the actual "proper" walk of the interrupt tree */
154 while (ipar != NULL) {
155 /* Now check if cursor is an interrupt-controller and if it is
156 * then we are done
157 */
158 if (of_get_property(ipar, "interrupt-controller", NULL) !=
159 NULL) {
160 pr_debug(" -> got it !\n");
Rob Herringa7c194b2010-06-08 07:48:08 -0600161 for (i = 0; i < intsize; i++)
162 out_irq->specifier[i] =
163 of_read_number(intspec +i, 1);
Grant Likely7dc2e112010-06-08 07:48:06 -0600164 out_irq->size = intsize;
165 out_irq->controller = ipar;
166 of_node_put(old);
167 return 0;
168 }
169
170 /* Now look for an interrupt-map */
171 imap = of_get_property(ipar, "interrupt-map", &imaplen);
172 /* No interrupt map, check for an interrupt parent */
173 if (imap == NULL) {
174 pr_debug(" -> no map, getting parent\n");
175 newpar = of_irq_find_parent(ipar);
176 goto skiplevel;
177 }
178 imaplen /= sizeof(u32);
179
180 /* Look for a mask */
181 imask = of_get_property(ipar, "interrupt-map-mask", NULL);
182
183 /* If we were passed no "reg" property and we attempt to parse
184 * an interrupt-map, then #address-cells must be 0.
185 * Fail if it's not.
186 */
187 if (addr == NULL && addrsize != 0) {
188 pr_debug(" -> no reg passed in when needed !\n");
189 goto fail;
190 }
191
192 /* Parse interrupt-map */
193 match = 0;
194 while (imaplen > (addrsize + intsize + 1) && !match) {
195 /* Compare specifiers */
196 match = 1;
197 for (i = 0; i < addrsize && match; ++i) {
198 u32 mask = imask ? imask[i] : 0xffffffffu;
199 match = ((addr[i] ^ imap[i]) & mask) == 0;
200 }
201 for (; i < (addrsize + intsize) && match; ++i) {
202 u32 mask = imask ? imask[i] : 0xffffffffu;
203 match =
204 ((intspec[i-addrsize] ^ imap[i]) & mask) == 0;
205 }
206 imap += addrsize + intsize;
207 imaplen -= addrsize + intsize;
208
209 pr_debug(" -> match=%d (imaplen=%d)\n", match, imaplen);
210
211 /* Get the interrupt parent */
212 if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
213 newpar = of_node_get(of_irq_dflt_pic);
214 else
Grant Likely9a6b2e52010-07-23 01:48:25 -0600215 newpar = of_find_node_by_phandle(be32_to_cpup(imap));
Grant Likely7dc2e112010-06-08 07:48:06 -0600216 imap++;
217 --imaplen;
218
219 /* Check if not found */
220 if (newpar == NULL) {
221 pr_debug(" -> imap parent not found !\n");
222 goto fail;
223 }
224
225 /* Get #interrupt-cells and #address-cells of new
226 * parent
227 */
228 tmp = of_get_property(newpar, "#interrupt-cells", NULL);
229 if (tmp == NULL) {
230 pr_debug(" -> parent lacks #interrupt-cells!\n");
231 goto fail;
232 }
Rob Herringa7c194b2010-06-08 07:48:08 -0600233 newintsize = be32_to_cpu(*tmp);
Grant Likely7dc2e112010-06-08 07:48:06 -0600234 tmp = of_get_property(newpar, "#address-cells", NULL);
Rob Herringa7c194b2010-06-08 07:48:08 -0600235 newaddrsize = (tmp == NULL) ? 0 : be32_to_cpu(*tmp);
Grant Likely7dc2e112010-06-08 07:48:06 -0600236
237 pr_debug(" -> newintsize=%d, newaddrsize=%d\n",
238 newintsize, newaddrsize);
239
240 /* Check for malformed properties */
241 if (imaplen < (newaddrsize + newintsize))
242 goto fail;
243
244 imap += newaddrsize + newintsize;
245 imaplen -= newaddrsize + newintsize;
246
247 pr_debug(" -> imaplen=%d\n", imaplen);
248 }
249 if (!match)
250 goto fail;
251
252 of_node_put(old);
253 old = of_node_get(newpar);
254 addrsize = newaddrsize;
255 intsize = newintsize;
256 intspec = imap - intsize;
257 addr = intspec - addrsize;
258
259 skiplevel:
260 /* Iterate again with new parent */
261 pr_debug(" -> new parent: %s\n", newpar ? newpar->full_name : "<>");
262 of_node_put(ipar);
263 ipar = newpar;
264 newpar = NULL;
265 }
266 fail:
267 of_node_put(ipar);
268 of_node_put(old);
269 of_node_put(newpar);
270
271 return -EINVAL;
272}
273EXPORT_SYMBOL_GPL(of_irq_map_raw);
274
275/**
276 * of_irq_map_one - Resolve an interrupt for a device
277 * @device: the device whose interrupt is to be resolved
278 * @index: index of the interrupt to resolve
279 * @out_irq: structure of_irq filled by this function
280 *
281 * This function resolves an interrupt, walking the tree, for a given
282 * device-tree node. It's the high level pendant to of_irq_map_raw().
283 */
284int of_irq_map_one(struct device_node *device, int index, struct of_irq *out_irq)
285{
286 struct device_node *p;
Grant Likelyd2f71832010-07-23 16:56:19 -0600287 const __be32 *intspec, *tmp, *addr;
Grant Likely7dc2e112010-06-08 07:48:06 -0600288 u32 intsize, intlen;
289 int res = -EINVAL;
290
291 pr_debug("of_irq_map_one: dev=%s, index=%d\n", device->full_name, index);
292
293 /* OldWorld mac stuff is "special", handle out of line */
294 if (of_irq_workarounds & OF_IMAP_OLDWORLD_MAC)
295 return of_irq_map_oldworld(device, index, out_irq);
296
297 /* Get the interrupts property */
298 intspec = of_get_property(device, "interrupts", &intlen);
299 if (intspec == NULL)
300 return -EINVAL;
Grant Likelyd2f71832010-07-23 16:56:19 -0600301 intlen /= sizeof(*intspec);
Grant Likely7dc2e112010-06-08 07:48:06 -0600302
Grant Likelyd2f71832010-07-23 16:56:19 -0600303 pr_debug(" intspec=%d intlen=%d\n", be32_to_cpup(intspec), intlen);
Grant Likely7dc2e112010-06-08 07:48:06 -0600304
305 /* Get the reg property (if any) */
306 addr = of_get_property(device, "reg", NULL);
307
308 /* Look for the interrupt parent. */
309 p = of_irq_find_parent(device);
310 if (p == NULL)
311 return -EINVAL;
312
313 /* Get size of interrupt specifier */
314 tmp = of_get_property(p, "#interrupt-cells", NULL);
315 if (tmp == NULL)
316 goto out;
Rob Herringa7c194b2010-06-08 07:48:08 -0600317 intsize = be32_to_cpu(*tmp);
Grant Likely7dc2e112010-06-08 07:48:06 -0600318
319 pr_debug(" intsize=%d intlen=%d\n", intsize, intlen);
320
321 /* Check index */
322 if ((index + 1) * intsize > intlen)
323 goto out;
324
325 /* Get new specifier and map it */
326 res = of_irq_map_raw(p, intspec + index * intsize, intsize,
327 addr, out_irq);
328 out:
329 of_node_put(p);
330 return res;
331}
332EXPORT_SYMBOL_GPL(of_irq_map_one);
333
334/**
335 * of_irq_to_resource - Decode a node's IRQ and return it as a resource
336 * @dev: pointer to device tree node
337 * @index: zero-based index of the irq
338 * @r: pointer to resource structure to return result into.
339 */
340int of_irq_to_resource(struct device_node *dev, int index, struct resource *r)
341{
342 int irq = irq_of_parse_and_map(dev, index);
343
344 /* Only dereference the resource if both the
345 * resource and the irq are valid. */
346 if (r && irq != NO_IRQ) {
347 r->start = r->end = irq;
348 r->flags = IORESOURCE_IRQ;
Grant Likelyd3571c32010-06-08 07:48:12 -0600349 r->name = dev->full_name;
Grant Likely7dc2e112010-06-08 07:48:06 -0600350 }
351
352 return irq;
353}
354EXPORT_SYMBOL_GPL(of_irq_to_resource);
Andres Salomon52f65372010-10-10 21:35:05 -0600355
356/**
357 * of_irq_count - Count the number of IRQs a node uses
358 * @dev: pointer to device tree node
359 */
360int of_irq_count(struct device_node *dev)
361{
362 int nr = 0;
363
364 while (of_irq_to_resource(dev, nr, NULL) != NO_IRQ)
365 nr++;
366
367 return nr;
368}
369
370/**
371 * of_irq_to_resource_table - Fill in resource table with node's IRQ info
372 * @dev: pointer to device tree node
373 * @res: array of resources to fill in
374 * @nr_irqs: the number of IRQs (and upper bound for num of @res elements)
375 *
376 * Returns the size of the filled in table (up to @nr_irqs).
377 */
378int of_irq_to_resource_table(struct device_node *dev, struct resource *res,
379 int nr_irqs)
380{
381 int i;
382
383 for (i = 0; i < nr_irqs; i++, res++)
384 if (of_irq_to_resource(dev, i, res) == NO_IRQ)
385 break;
386
387 return i;
388}