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_map_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
)
41 if (of_irq_map_one(dev
, index
, &oirq
))
44 return irq_create_of_mapping(oirq
.controller
, oirq
.specifier
,
47 EXPORT_SYMBOL_GPL(irq_of_parse_and_map
);
50 * of_irq_find_parent - Given a device node, find its interrupt parent node
51 * @child: pointer to device node
53 * Returns a pointer to the interrupt parent node, or NULL if the interrupt
54 * parent could not be determined.
56 struct device_node
*of_irq_find_parent(struct device_node
*child
)
58 struct device_node
*p
;
61 if (!of_node_get(child
))
65 parp
= of_get_property(child
, "interrupt-parent", NULL
);
67 p
= of_get_parent(child
);
69 if (of_irq_workarounds
& OF_IMAP_NO_PHANDLE
)
70 p
= of_node_get(of_irq_dflt_pic
);
72 p
= of_find_node_by_phandle(be32_to_cpup(parp
));
76 } while (p
&& of_get_property(p
, "#interrupt-cells", NULL
) == NULL
);
82 * of_irq_map_raw - Low level interrupt tree parsing
83 * @parent: the device interrupt parent
84 * @intspec: interrupt specifier ("interrupts" property of the device)
85 * @ointsize: size of the passed in interrupt specifier
86 * @addr: address specifier (start of "reg" property of the device)
87 * @out_irq: structure of_irq filled by this function
89 * Returns 0 on success and a negative number on error
91 * This function is a low-level interrupt tree walking function. It
92 * can be used to do a partial walk with synthetized reg and interrupts
93 * properties, for example when resolving PCI interrupts when no device
94 * node exist for the parent.
96 int of_irq_map_raw(struct device_node
*parent
, const __be32
*intspec
,
97 u32 ointsize
, const __be32
*addr
, struct of_irq
*out_irq
)
99 struct device_node
*ipar
, *tnode
, *old
= NULL
, *newpar
= NULL
;
100 const __be32
*tmp
, *imap
, *imask
;
101 u32 intsize
= 1, addrsize
, newintsize
= 0, newaddrsize
= 0;
102 int imaplen
, match
, i
;
104 pr_debug("of_irq_map_raw: par=%s,intspec=[0x%08x 0x%08x...],ointsize=%d\n",
105 parent
->full_name
, be32_to_cpup(intspec
),
106 be32_to_cpup(intspec
+ 1), ointsize
);
108 ipar
= of_node_get(parent
);
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_map_raw: ipar=%s, size=%d\n", ipar
->full_name
, intsize
);
131 if (ointsize
!= 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 /* Now start the actual "proper" walk of the interrupt tree */
151 while (ipar
!= NULL
) {
152 /* Now check if cursor is an interrupt-controller and if it is
155 if (of_get_property(ipar
, "interrupt-controller", NULL
) !=
157 pr_debug(" -> got it !\n");
158 for (i
= 0; i
< intsize
; i
++)
159 out_irq
->specifier
[i
] =
160 of_read_number(intspec
+i
, 1);
161 out_irq
->size
= intsize
;
162 out_irq
->controller
= ipar
;
167 /* Now look for an interrupt-map */
168 imap
= of_get_property(ipar
, "interrupt-map", &imaplen
);
169 /* No interrupt map, check for an interrupt parent */
171 pr_debug(" -> no map, getting parent\n");
172 newpar
= of_irq_find_parent(ipar
);
175 imaplen
/= sizeof(u32
);
177 /* Look for a mask */
178 imask
= of_get_property(ipar
, "interrupt-map-mask", NULL
);
180 /* If we were passed no "reg" property and we attempt to parse
181 * an interrupt-map, then #address-cells must be 0.
184 if (addr
== NULL
&& addrsize
!= 0) {
185 pr_debug(" -> no reg passed in when needed !\n");
189 /* Parse interrupt-map */
191 while (imaplen
> (addrsize
+ intsize
+ 1) && !match
) {
192 /* Compare specifiers */
194 for (i
= 0; i
< addrsize
&& match
; ++i
) {
195 __be32 mask
= imask
? imask
[i
]
196 : cpu_to_be32(0xffffffffu
);
197 match
= ((addr
[i
] ^ imap
[i
]) & mask
) == 0;
199 for (; i
< (addrsize
+ intsize
) && match
; ++i
) {
200 __be32 mask
= imask
? imask
[i
]
201 : cpu_to_be32(0xffffffffu
);
203 ((intspec
[i
-addrsize
] ^ imap
[i
]) & mask
) == 0;
205 imap
+= addrsize
+ intsize
;
206 imaplen
-= addrsize
+ intsize
;
208 pr_debug(" -> match=%d (imaplen=%d)\n", match
, imaplen
);
210 /* Get the interrupt parent */
211 if (of_irq_workarounds
& OF_IMAP_NO_PHANDLE
)
212 newpar
= of_node_get(of_irq_dflt_pic
);
214 newpar
= of_find_node_by_phandle(be32_to_cpup(imap
));
218 /* Check if not found */
219 if (newpar
== NULL
) {
220 pr_debug(" -> imap parent not found !\n");
224 /* Get #interrupt-cells and #address-cells of new
227 tmp
= of_get_property(newpar
, "#interrupt-cells", NULL
);
229 pr_debug(" -> parent lacks #interrupt-cells!\n");
232 newintsize
= be32_to_cpu(*tmp
);
233 tmp
= of_get_property(newpar
, "#address-cells", NULL
);
234 newaddrsize
= (tmp
== NULL
) ? 0 : be32_to_cpu(*tmp
);
236 pr_debug(" -> newintsize=%d, newaddrsize=%d\n",
237 newintsize
, newaddrsize
);
239 /* Check for malformed properties */
240 if (imaplen
< (newaddrsize
+ newintsize
))
243 imap
+= newaddrsize
+ newintsize
;
244 imaplen
-= newaddrsize
+ newintsize
;
246 pr_debug(" -> imaplen=%d\n", imaplen
);
252 old
= of_node_get(newpar
);
253 addrsize
= newaddrsize
;
254 intsize
= newintsize
;
255 intspec
= imap
- intsize
;
256 addr
= intspec
- addrsize
;
259 /* Iterate again with new parent */
260 pr_debug(" -> new parent: %s\n", of_node_full_name(newpar
));
272 EXPORT_SYMBOL_GPL(of_irq_map_raw
);
275 * of_irq_map_one - Resolve an interrupt for a device
276 * @device: the device whose interrupt is to be resolved
277 * @index: index of the interrupt to resolve
278 * @out_irq: structure of_irq filled by this function
280 * This function resolves an interrupt, walking the tree, for a given
281 * device-tree node. It's the high level pendant to of_irq_map_raw().
283 int of_irq_map_one(struct device_node
*device
, int index
, struct of_irq
*out_irq
)
285 struct device_node
*p
;
286 const __be32
*intspec
, *tmp
, *addr
;
290 pr_debug("of_irq_map_one: dev=%s, index=%d\n", device
->full_name
, index
);
292 /* OldWorld mac stuff is "special", handle out of line */
293 if (of_irq_workarounds
& OF_IMAP_OLDWORLD_MAC
)
294 return of_irq_map_oldworld(device
, index
, out_irq
);
296 /* Get the interrupts property */
297 intspec
= of_get_property(device
, "interrupts", &intlen
);
300 intlen
/= sizeof(*intspec
);
302 pr_debug(" intspec=%d intlen=%d\n", be32_to_cpup(intspec
), intlen
);
304 /* Get the reg property (if any) */
305 addr
= of_get_property(device
, "reg", NULL
);
307 /* Look for the interrupt parent. */
308 p
= of_irq_find_parent(device
);
312 /* Get size of interrupt specifier */
313 tmp
= of_get_property(p
, "#interrupt-cells", NULL
);
316 intsize
= be32_to_cpu(*tmp
);
318 pr_debug(" intsize=%d intlen=%d\n", intsize
, intlen
);
321 if ((index
+ 1) * intsize
> intlen
)
324 /* Get new specifier and map it */
325 res
= of_irq_map_raw(p
, intspec
+ index
* intsize
, intsize
,
331 EXPORT_SYMBOL_GPL(of_irq_map_one
);
334 * of_irq_to_resource - Decode a node's IRQ and return it as a resource
335 * @dev: pointer to device tree node
336 * @index: zero-based index of the irq
337 * @r: pointer to resource structure to return result into.
339 int of_irq_to_resource(struct device_node
*dev
, int index
, struct resource
*r
)
341 int irq
= irq_of_parse_and_map(dev
, index
);
343 /* Only dereference the resource if both the
344 * resource and the irq are valid. */
346 const char *name
= NULL
;
348 memset(r
, 0, sizeof(*r
));
350 * Get optional "interrupts-names" property to add a name
353 of_property_read_string_index(dev
, "interrupt-names", index
,
356 r
->start
= r
->end
= irq
;
357 r
->flags
= IORESOURCE_IRQ
;
358 r
->name
= name
? name
: dev
->full_name
;
363 EXPORT_SYMBOL_GPL(of_irq_to_resource
);
366 * of_irq_count - Count the number of IRQs a node uses
367 * @dev: pointer to device tree node
369 int of_irq_count(struct device_node
*dev
)
373 while (of_irq_to_resource(dev
, nr
, NULL
))
380 * of_irq_to_resource_table - Fill in resource table with node's IRQ info
381 * @dev: pointer to device tree node
382 * @res: array of resources to fill in
383 * @nr_irqs: the number of IRQs (and upper bound for num of @res elements)
385 * Returns the size of the filled in table (up to @nr_irqs).
387 int of_irq_to_resource_table(struct device_node
*dev
, struct resource
*res
,
392 for (i
= 0; i
< nr_irqs
; i
++, res
++)
393 if (!of_irq_to_resource(dev
, i
, res
))
398 EXPORT_SYMBOL_GPL(of_irq_to_resource_table
);
401 struct list_head list
;
402 struct device_node
*dev
;
403 struct device_node
*interrupt_parent
;
407 * of_irq_init - Scan and init matching interrupt controllers in DT
408 * @matches: 0 terminated array of nodes to match and init function to call
410 * This function scans the device tree for matching interrupt controller nodes,
411 * and calls their initialization functions in order with parents first.
413 void __init
of_irq_init(const struct of_device_id
*matches
)
415 struct device_node
*np
, *parent
= NULL
;
416 struct intc_desc
*desc
, *temp_desc
;
417 struct list_head intc_desc_list
, intc_parent_list
;
419 INIT_LIST_HEAD(&intc_desc_list
);
420 INIT_LIST_HEAD(&intc_parent_list
);
422 for_each_matching_node(np
, matches
) {
423 if (!of_find_property(np
, "interrupt-controller", NULL
))
426 * Here, we allocate and populate an intc_desc with the node
427 * pointer, interrupt-parent device_node etc.
429 desc
= kzalloc(sizeof(*desc
), GFP_KERNEL
);
434 desc
->interrupt_parent
= of_irq_find_parent(np
);
435 if (desc
->interrupt_parent
== np
)
436 desc
->interrupt_parent
= NULL
;
437 list_add_tail(&desc
->list
, &intc_desc_list
);
441 * The root irq controller is the one without an interrupt-parent.
442 * That one goes first, followed by the controllers that reference it,
443 * followed by the ones that reference the 2nd level controllers, etc.
445 while (!list_empty(&intc_desc_list
)) {
447 * Process all controllers with the current 'parent'.
448 * First pass will be looking for NULL as the parent.
449 * The assumption is that NULL parent means a root controller.
451 list_for_each_entry_safe(desc
, temp_desc
, &intc_desc_list
, list
) {
452 const struct of_device_id
*match
;
454 of_irq_init_cb_t irq_init_cb
;
456 if (desc
->interrupt_parent
!= parent
)
459 list_del(&desc
->list
);
460 match
= of_match_node(matches
, desc
->dev
);
461 if (WARN(!match
->data
,
462 "of_irq_init: no init function for %s\n",
463 match
->compatible
)) {
468 pr_debug("of_irq_init: init %s @ %p, parent %p\n",
470 desc
->dev
, desc
->interrupt_parent
);
471 irq_init_cb
= (of_irq_init_cb_t
)match
->data
;
472 ret
= irq_init_cb(desc
->dev
, desc
->interrupt_parent
);
479 * This one is now set up; add it to the parent list so
480 * its children can get processed in a subsequent pass.
482 list_add_tail(&desc
->list
, &intc_parent_list
);
485 /* Get the next pending parent that might have children */
486 desc
= list_first_entry_or_null(&intc_parent_list
,
487 typeof(*desc
), list
);
489 pr_err("of_irq_init: children remain, but no parents\n");
492 list_del(&desc
->list
);
497 list_for_each_entry_safe(desc
, temp_desc
, &intc_parent_list
, list
) {
498 list_del(&desc
->list
);
502 list_for_each_entry_safe(desc
, temp_desc
, &intc_desc_list
, list
) {
503 list_del(&desc
->list
);