xref: /openbmc/linux/kernel/irq/irqdomain.c (revision 9f380456)
1 #include <linux/debugfs.h>
2 #include <linux/hardirq.h>
3 #include <linux/interrupt.h>
4 #include <linux/irq.h>
5 #include <linux/irqdesc.h>
6 #include <linux/irqdomain.h>
7 #include <linux/module.h>
8 #include <linux/mutex.h>
9 #include <linux/of.h>
10 #include <linux/of_address.h>
11 #include <linux/seq_file.h>
12 #include <linux/slab.h>
13 #include <linux/smp.h>
14 #include <linux/fs.h>
15 
16 #define IRQ_DOMAIN_MAP_LEGACY 0 /* driver allocated fixed range of irqs.
17 				 * ie. legacy 8259, gets irqs 1..15 */
18 #define IRQ_DOMAIN_MAP_NOMAP 1 /* no fast reverse mapping */
19 #define IRQ_DOMAIN_MAP_LINEAR 2 /* linear map of interrupts */
20 #define IRQ_DOMAIN_MAP_TREE 3 /* radix tree */
21 
22 static LIST_HEAD(irq_domain_list);
23 static DEFINE_MUTEX(irq_domain_mutex);
24 
25 static DEFINE_MUTEX(revmap_trees_mutex);
26 static struct irq_domain *irq_default_domain;
27 
28 /**
29  * irq_domain_alloc() - Allocate a new irq_domain data structure
30  * @of_node: optional device-tree node of the interrupt controller
31  * @revmap_type: type of reverse mapping to use
32  * @ops: map/unmap domain callbacks
33  * @host_data: Controller private data pointer
34  *
35  * Allocates and initialize and irq_domain structure.  Caller is expected to
36  * register allocated irq_domain with irq_domain_register().  Returns pointer
37  * to IRQ domain, or NULL on failure.
38  */
39 static struct irq_domain *irq_domain_alloc(struct device_node *of_node,
40 					   unsigned int revmap_type,
41 					   const struct irq_domain_ops *ops,
42 					   void *host_data)
43 {
44 	struct irq_domain *domain;
45 
46 	domain = kzalloc(sizeof(*domain), GFP_KERNEL);
47 	if (WARN_ON(!domain))
48 		return NULL;
49 
50 	/* Fill structure */
51 	domain->revmap_type = revmap_type;
52 	domain->ops = ops;
53 	domain->host_data = host_data;
54 	domain->of_node = of_node_get(of_node);
55 
56 	return domain;
57 }
58 
59 static void irq_domain_add(struct irq_domain *domain)
60 {
61 	mutex_lock(&irq_domain_mutex);
62 	list_add(&domain->link, &irq_domain_list);
63 	mutex_unlock(&irq_domain_mutex);
64 	pr_debug("irq: Allocated domain of type %d @0x%p\n",
65 		 domain->revmap_type, domain);
66 }
67 
68 static unsigned int irq_domain_legacy_revmap(struct irq_domain *domain,
69 					     irq_hw_number_t hwirq)
70 {
71 	irq_hw_number_t first_hwirq = domain->revmap_data.legacy.first_hwirq;
72 	int size = domain->revmap_data.legacy.size;
73 
74 	if (WARN_ON(hwirq < first_hwirq || hwirq >= first_hwirq + size))
75 		return 0;
76 	return hwirq - first_hwirq + domain->revmap_data.legacy.first_irq;
77 }
78 
79 /**
80  * irq_domain_add_legacy() - Allocate and register a legacy revmap irq_domain.
81  * @of_node: pointer to interrupt controller's device tree node.
82  * @size: total number of irqs in legacy mapping
83  * @first_irq: first number of irq block assigned to the domain
84  * @first_hwirq: first hwirq number to use for the translation. Should normally
85  *               be '0', but a positive integer can be used if the effective
86  *               hwirqs numbering does not begin at zero.
87  * @ops: map/unmap domain callbacks
88  * @host_data: Controller private data pointer
89  *
90  * Note: the map() callback will be called before this function returns
91  * for all legacy interrupts except 0 (which is always the invalid irq for
92  * a legacy controller).
93  */
94 struct irq_domain *irq_domain_add_legacy(struct device_node *of_node,
95 					 unsigned int size,
96 					 unsigned int first_irq,
97 					 irq_hw_number_t first_hwirq,
98 					 const struct irq_domain_ops *ops,
99 					 void *host_data)
100 {
101 	struct irq_domain *domain;
102 	unsigned int i;
103 
104 	domain = irq_domain_alloc(of_node, IRQ_DOMAIN_MAP_LEGACY, ops, host_data);
105 	if (!domain)
106 		return NULL;
107 
108 	domain->revmap_data.legacy.first_irq = first_irq;
109 	domain->revmap_data.legacy.first_hwirq = first_hwirq;
110 	domain->revmap_data.legacy.size = size;
111 
112 	mutex_lock(&irq_domain_mutex);
113 	/* Verify that all the irqs are available */
114 	for (i = 0; i < size; i++) {
115 		int irq = first_irq + i;
116 		struct irq_data *irq_data = irq_get_irq_data(irq);
117 
118 		if (WARN_ON(!irq_data || irq_data->domain)) {
119 			mutex_unlock(&irq_domain_mutex);
120 			of_node_put(domain->of_node);
121 			kfree(domain);
122 			return NULL;
123 		}
124 	}
125 
126 	/* Claim all of the irqs before registering a legacy domain */
127 	for (i = 0; i < size; i++) {
128 		struct irq_data *irq_data = irq_get_irq_data(first_irq + i);
129 		irq_data->hwirq = first_hwirq + i;
130 		irq_data->domain = domain;
131 	}
132 	mutex_unlock(&irq_domain_mutex);
133 
134 	for (i = 0; i < size; i++) {
135 		int irq = first_irq + i;
136 		int hwirq = first_hwirq + i;
137 
138 		/* IRQ0 gets ignored */
139 		if (!irq)
140 			continue;
141 
142 		/* Legacy flags are left to default at this point,
143 		 * one can then use irq_create_mapping() to
144 		 * explicitly change them
145 		 */
146 		ops->map(domain, irq, hwirq);
147 
148 		/* Clear norequest flags */
149 		irq_clear_status_flags(irq, IRQ_NOREQUEST);
150 	}
151 
152 	irq_domain_add(domain);
153 	return domain;
154 }
155 
156 /**
157  * irq_domain_add_linear() - Allocate and register a legacy revmap irq_domain.
158  * @of_node: pointer to interrupt controller's device tree node.
159  * @ops: map/unmap domain callbacks
160  * @host_data: Controller private data pointer
161  */
162 struct irq_domain *irq_domain_add_linear(struct device_node *of_node,
163 					 unsigned int size,
164 					 const struct irq_domain_ops *ops,
165 					 void *host_data)
166 {
167 	struct irq_domain *domain;
168 	unsigned int *revmap;
169 
170 	revmap = kzalloc(sizeof(*revmap) * size, GFP_KERNEL);
171 	if (WARN_ON(!revmap))
172 		return NULL;
173 
174 	domain = irq_domain_alloc(of_node, IRQ_DOMAIN_MAP_LINEAR, ops, host_data);
175 	if (!domain) {
176 		kfree(revmap);
177 		return NULL;
178 	}
179 	domain->revmap_data.linear.size = size;
180 	domain->revmap_data.linear.revmap = revmap;
181 	irq_domain_add(domain);
182 	return domain;
183 }
184 
185 struct irq_domain *irq_domain_add_nomap(struct device_node *of_node,
186 					 unsigned int max_irq,
187 					 const struct irq_domain_ops *ops,
188 					 void *host_data)
189 {
190 	struct irq_domain *domain = irq_domain_alloc(of_node,
191 					IRQ_DOMAIN_MAP_NOMAP, ops, host_data);
192 	if (domain) {
193 		domain->revmap_data.nomap.max_irq = max_irq ? max_irq : ~0;
194 		irq_domain_add(domain);
195 	}
196 	return domain;
197 }
198 
199 /**
200  * irq_domain_add_tree()
201  * @of_node: pointer to interrupt controller's device tree node.
202  * @ops: map/unmap domain callbacks
203  *
204  * Note: The radix tree will be allocated later during boot automatically
205  * (the reverse mapping will use the slow path until that happens).
206  */
207 struct irq_domain *irq_domain_add_tree(struct device_node *of_node,
208 					 const struct irq_domain_ops *ops,
209 					 void *host_data)
210 {
211 	struct irq_domain *domain = irq_domain_alloc(of_node,
212 					IRQ_DOMAIN_MAP_TREE, ops, host_data);
213 	if (domain) {
214 		INIT_RADIX_TREE(&domain->revmap_data.tree, GFP_KERNEL);
215 		irq_domain_add(domain);
216 	}
217 	return domain;
218 }
219 
220 /**
221  * irq_find_host() - Locates a domain for a given device node
222  * @node: device-tree node of the interrupt controller
223  */
224 struct irq_domain *irq_find_host(struct device_node *node)
225 {
226 	struct irq_domain *h, *found = NULL;
227 	int rc;
228 
229 	/* We might want to match the legacy controller last since
230 	 * it might potentially be set to match all interrupts in
231 	 * the absence of a device node. This isn't a problem so far
232 	 * yet though...
233 	 */
234 	mutex_lock(&irq_domain_mutex);
235 	list_for_each_entry(h, &irq_domain_list, link) {
236 		if (h->ops->match)
237 			rc = h->ops->match(h, node);
238 		else
239 			rc = (h->of_node != NULL) && (h->of_node == node);
240 
241 		if (rc) {
242 			found = h;
243 			break;
244 		}
245 	}
246 	mutex_unlock(&irq_domain_mutex);
247 	return found;
248 }
249 EXPORT_SYMBOL_GPL(irq_find_host);
250 
251 /**
252  * irq_set_default_host() - Set a "default" irq domain
253  * @domain: default domain pointer
254  *
255  * For convenience, it's possible to set a "default" domain that will be used
256  * whenever NULL is passed to irq_create_mapping(). It makes life easier for
257  * platforms that want to manipulate a few hard coded interrupt numbers that
258  * aren't properly represented in the device-tree.
259  */
260 void irq_set_default_host(struct irq_domain *domain)
261 {
262 	pr_debug("irq: Default domain set to @0x%p\n", domain);
263 
264 	irq_default_domain = domain;
265 }
266 
267 static int irq_setup_virq(struct irq_domain *domain, unsigned int virq,
268 			    irq_hw_number_t hwirq)
269 {
270 	struct irq_data *irq_data = irq_get_irq_data(virq);
271 
272 	irq_data->hwirq = hwirq;
273 	irq_data->domain = domain;
274 	if (domain->ops->map(domain, virq, hwirq)) {
275 		pr_debug("irq: -> mapping failed, freeing\n");
276 		irq_data->domain = NULL;
277 		irq_data->hwirq = 0;
278 		return -1;
279 	}
280 
281 	irq_clear_status_flags(virq, IRQ_NOREQUEST);
282 
283 	return 0;
284 }
285 
286 /**
287  * irq_create_direct_mapping() - Allocate an irq for direct mapping
288  * @domain: domain to allocate the irq for or NULL for default domain
289  *
290  * This routine is used for irq controllers which can choose the hardware
291  * interrupt numbers they generate. In such a case it's simplest to use
292  * the linux irq as the hardware interrupt number.
293  */
294 unsigned int irq_create_direct_mapping(struct irq_domain *domain)
295 {
296 	unsigned int virq;
297 
298 	if (domain == NULL)
299 		domain = irq_default_domain;
300 
301 	BUG_ON(domain == NULL);
302 	WARN_ON(domain->revmap_type != IRQ_DOMAIN_MAP_NOMAP);
303 
304 	virq = irq_alloc_desc_from(1, 0);
305 	if (!virq) {
306 		pr_debug("irq: create_direct virq allocation failed\n");
307 		return 0;
308 	}
309 	if (virq >= domain->revmap_data.nomap.max_irq) {
310 		pr_err("ERROR: no free irqs available below %i maximum\n",
311 			domain->revmap_data.nomap.max_irq);
312 		irq_free_desc(virq);
313 		return 0;
314 	}
315 	pr_debug("irq: create_direct obtained virq %d\n", virq);
316 
317 	if (irq_setup_virq(domain, virq, virq)) {
318 		irq_free_desc(virq);
319 		return 0;
320 	}
321 
322 	return virq;
323 }
324 
325 /**
326  * irq_create_mapping() - Map a hardware interrupt into linux irq space
327  * @domain: domain owning this hardware interrupt or NULL for default domain
328  * @hwirq: hardware irq number in that domain space
329  *
330  * Only one mapping per hardware interrupt is permitted. Returns a linux
331  * irq number.
332  * If the sense/trigger is to be specified, set_irq_type() should be called
333  * on the number returned from that call.
334  */
335 unsigned int irq_create_mapping(struct irq_domain *domain,
336 				irq_hw_number_t hwirq)
337 {
338 	unsigned int hint;
339 	int virq;
340 
341 	pr_debug("irq: irq_create_mapping(0x%p, 0x%lx)\n", domain, hwirq);
342 
343 	/* Look for default domain if nececssary */
344 	if (domain == NULL)
345 		domain = irq_default_domain;
346 	if (domain == NULL) {
347 		printk(KERN_WARNING "irq_create_mapping called for"
348 		       " NULL domain, hwirq=%lx\n", hwirq);
349 		WARN_ON(1);
350 		return 0;
351 	}
352 	pr_debug("irq: -> using domain @%p\n", domain);
353 
354 	/* Check if mapping already exists */
355 	virq = irq_find_mapping(domain, hwirq);
356 	if (virq) {
357 		pr_debug("irq: -> existing mapping on virq %d\n", virq);
358 		return virq;
359 	}
360 
361 	/* Get a virtual interrupt number */
362 	if (domain->revmap_type == IRQ_DOMAIN_MAP_LEGACY)
363 		return irq_domain_legacy_revmap(domain, hwirq);
364 
365 	/* Allocate a virtual interrupt number */
366 	hint = hwirq % nr_irqs;
367 	if (hint == 0)
368 		hint++;
369 	virq = irq_alloc_desc_from(hint, 0);
370 	if (virq <= 0)
371 		virq = irq_alloc_desc_from(1, 0);
372 	if (virq <= 0) {
373 		pr_debug("irq: -> virq allocation failed\n");
374 		return 0;
375 	}
376 
377 	if (irq_setup_virq(domain, virq, hwirq)) {
378 		if (domain->revmap_type != IRQ_DOMAIN_MAP_LEGACY)
379 			irq_free_desc(virq);
380 		return 0;
381 	}
382 
383 	pr_debug("irq: irq %lu on domain %s mapped to virtual irq %u\n",
384 		hwirq, domain->of_node ? domain->of_node->full_name : "null", virq);
385 
386 	return virq;
387 }
388 EXPORT_SYMBOL_GPL(irq_create_mapping);
389 
390 unsigned int irq_create_of_mapping(struct device_node *controller,
391 				   const u32 *intspec, unsigned int intsize)
392 {
393 	struct irq_domain *domain;
394 	irq_hw_number_t hwirq;
395 	unsigned int type = IRQ_TYPE_NONE;
396 	unsigned int virq;
397 
398 	domain = controller ? irq_find_host(controller) : irq_default_domain;
399 	if (!domain) {
400 #ifdef CONFIG_MIPS
401 		/*
402 		 * Workaround to avoid breaking interrupt controller drivers
403 		 * that don't yet register an irq_domain.  This is temporary
404 		 * code. ~~~gcl, Feb 24, 2012
405 		 *
406 		 * Scheduled for removal in Linux v3.6.  That should be enough
407 		 * time.
408 		 */
409 		if (intsize > 0)
410 			return intspec[0];
411 #endif
412 		printk(KERN_WARNING "irq: no irq domain found for %s !\n",
413 		       controller->full_name);
414 		return 0;
415 	}
416 
417 	/* If domain has no translation, then we assume interrupt line */
418 	if (domain->ops->xlate == NULL)
419 		hwirq = intspec[0];
420 	else {
421 		if (domain->ops->xlate(domain, controller, intspec, intsize,
422 				     &hwirq, &type))
423 			return 0;
424 	}
425 
426 	/* Create mapping */
427 	virq = irq_create_mapping(domain, hwirq);
428 	if (!virq)
429 		return virq;
430 
431 	/* Set type if specified and different than the current one */
432 	if (type != IRQ_TYPE_NONE &&
433 	    type != (irqd_get_trigger_type(irq_get_irq_data(virq))))
434 		irq_set_irq_type(virq, type);
435 	return virq;
436 }
437 EXPORT_SYMBOL_GPL(irq_create_of_mapping);
438 
439 /**
440  * irq_dispose_mapping() - Unmap an interrupt
441  * @virq: linux irq number of the interrupt to unmap
442  */
443 void irq_dispose_mapping(unsigned int virq)
444 {
445 	struct irq_data *irq_data = irq_get_irq_data(virq);
446 	struct irq_domain *domain;
447 	irq_hw_number_t hwirq;
448 
449 	if (!virq || !irq_data)
450 		return;
451 
452 	domain = irq_data->domain;
453 	if (WARN_ON(domain == NULL))
454 		return;
455 
456 	/* Never unmap legacy interrupts */
457 	if (domain->revmap_type == IRQ_DOMAIN_MAP_LEGACY)
458 		return;
459 
460 	irq_set_status_flags(virq, IRQ_NOREQUEST);
461 
462 	/* remove chip and handler */
463 	irq_set_chip_and_handler(virq, NULL, NULL);
464 
465 	/* Make sure it's completed */
466 	synchronize_irq(virq);
467 
468 	/* Tell the PIC about it */
469 	if (domain->ops->unmap)
470 		domain->ops->unmap(domain, virq);
471 	smp_mb();
472 
473 	/* Clear reverse map */
474 	hwirq = irq_data->hwirq;
475 	switch(domain->revmap_type) {
476 	case IRQ_DOMAIN_MAP_LINEAR:
477 		if (hwirq < domain->revmap_data.linear.size)
478 			domain->revmap_data.linear.revmap[hwirq] = 0;
479 		break;
480 	case IRQ_DOMAIN_MAP_TREE:
481 		mutex_lock(&revmap_trees_mutex);
482 		radix_tree_delete(&domain->revmap_data.tree, hwirq);
483 		mutex_unlock(&revmap_trees_mutex);
484 		break;
485 	}
486 
487 	irq_free_desc(virq);
488 }
489 EXPORT_SYMBOL_GPL(irq_dispose_mapping);
490 
491 /**
492  * irq_find_mapping() - Find a linux irq from an hw irq number.
493  * @domain: domain owning this hardware interrupt
494  * @hwirq: hardware irq number in that domain space
495  *
496  * This is a slow path, for use by generic code. It's expected that an
497  * irq controller implementation directly calls the appropriate low level
498  * mapping function.
499  */
500 unsigned int irq_find_mapping(struct irq_domain *domain,
501 			      irq_hw_number_t hwirq)
502 {
503 	unsigned int i;
504 	unsigned int hint = hwirq % nr_irqs;
505 
506 	/* Look for default domain if nececssary */
507 	if (domain == NULL)
508 		domain = irq_default_domain;
509 	if (domain == NULL)
510 		return 0;
511 
512 	/* legacy -> bail early */
513 	if (domain->revmap_type == IRQ_DOMAIN_MAP_LEGACY)
514 		return irq_domain_legacy_revmap(domain, hwirq);
515 
516 	/* Slow path does a linear search of the map */
517 	if (hint == 0)
518 		hint = 1;
519 	i = hint;
520 	do {
521 		struct irq_data *data = irq_get_irq_data(i);
522 		if (data && (data->domain == domain) && (data->hwirq == hwirq))
523 			return i;
524 		i++;
525 		if (i >= nr_irqs)
526 			i = 1;
527 	} while(i != hint);
528 	return 0;
529 }
530 EXPORT_SYMBOL_GPL(irq_find_mapping);
531 
532 /**
533  * irq_radix_revmap_lookup() - Find a linux irq from a hw irq number.
534  * @domain: domain owning this hardware interrupt
535  * @hwirq: hardware irq number in that domain space
536  *
537  * This is a fast path, for use by irq controller code that uses radix tree
538  * revmaps
539  */
540 unsigned int irq_radix_revmap_lookup(struct irq_domain *domain,
541 				     irq_hw_number_t hwirq)
542 {
543 	struct irq_data *irq_data;
544 
545 	if (WARN_ON_ONCE(domain->revmap_type != IRQ_DOMAIN_MAP_TREE))
546 		return irq_find_mapping(domain, hwirq);
547 
548 	/*
549 	 * Freeing an irq can delete nodes along the path to
550 	 * do the lookup via call_rcu.
551 	 */
552 	rcu_read_lock();
553 	irq_data = radix_tree_lookup(&domain->revmap_data.tree, hwirq);
554 	rcu_read_unlock();
555 
556 	/*
557 	 * If found in radix tree, then fine.
558 	 * Else fallback to linear lookup - this should not happen in practice
559 	 * as it means that we failed to insert the node in the radix tree.
560 	 */
561 	return irq_data ? irq_data->irq : irq_find_mapping(domain, hwirq);
562 }
563 
564 /**
565  * irq_radix_revmap_insert() - Insert a hw irq to linux irq number mapping.
566  * @domain: domain owning this hardware interrupt
567  * @virq: linux irq number
568  * @hwirq: hardware irq number in that domain space
569  *
570  * This is for use by irq controllers that use a radix tree reverse
571  * mapping for fast lookup.
572  */
573 void irq_radix_revmap_insert(struct irq_domain *domain, unsigned int virq,
574 			     irq_hw_number_t hwirq)
575 {
576 	struct irq_data *irq_data = irq_get_irq_data(virq);
577 
578 	if (WARN_ON(domain->revmap_type != IRQ_DOMAIN_MAP_TREE))
579 		return;
580 
581 	if (virq) {
582 		mutex_lock(&revmap_trees_mutex);
583 		radix_tree_insert(&domain->revmap_data.tree, hwirq, irq_data);
584 		mutex_unlock(&revmap_trees_mutex);
585 	}
586 }
587 
588 /**
589  * irq_linear_revmap() - Find a linux irq from a hw irq number.
590  * @domain: domain owning this hardware interrupt
591  * @hwirq: hardware irq number in that domain space
592  *
593  * This is a fast path, for use by irq controller code that uses linear
594  * revmaps. It does fallback to the slow path if the revmap doesn't exist
595  * yet and will create the revmap entry with appropriate locking
596  */
597 unsigned int irq_linear_revmap(struct irq_domain *domain,
598 			       irq_hw_number_t hwirq)
599 {
600 	unsigned int *revmap;
601 
602 	if (WARN_ON_ONCE(domain->revmap_type != IRQ_DOMAIN_MAP_LINEAR))
603 		return irq_find_mapping(domain, hwirq);
604 
605 	/* Check revmap bounds */
606 	if (unlikely(hwirq >= domain->revmap_data.linear.size))
607 		return irq_find_mapping(domain, hwirq);
608 
609 	/* Check if revmap was allocated */
610 	revmap = domain->revmap_data.linear.revmap;
611 	if (unlikely(revmap == NULL))
612 		return irq_find_mapping(domain, hwirq);
613 
614 	/* Fill up revmap with slow path if no mapping found */
615 	if (unlikely(!revmap[hwirq]))
616 		revmap[hwirq] = irq_find_mapping(domain, hwirq);
617 
618 	return revmap[hwirq];
619 }
620 
621 #ifdef CONFIG_IRQ_DOMAIN_DEBUG
622 static int virq_debug_show(struct seq_file *m, void *private)
623 {
624 	unsigned long flags;
625 	struct irq_desc *desc;
626 	const char *p;
627 	static const char none[] = "none";
628 	void *data;
629 	int i;
630 
631 	seq_printf(m, "%-5s  %-7s  %-15s  %-*s  %s\n", "irq", "hwirq",
632 		      "chip name", (int)(2 * sizeof(void *) + 2), "chip data",
633 		      "domain name");
634 
635 	for (i = 1; i < nr_irqs; i++) {
636 		desc = irq_to_desc(i);
637 		if (!desc)
638 			continue;
639 
640 		raw_spin_lock_irqsave(&desc->lock, flags);
641 
642 		if (desc->action && desc->action->handler) {
643 			struct irq_chip *chip;
644 
645 			seq_printf(m, "%5d  ", i);
646 			seq_printf(m, "0x%05lx  ", desc->irq_data.hwirq);
647 
648 			chip = irq_desc_get_chip(desc);
649 			if (chip && chip->name)
650 				p = chip->name;
651 			else
652 				p = none;
653 			seq_printf(m, "%-15s  ", p);
654 
655 			data = irq_desc_get_chip_data(desc);
656 			seq_printf(m, data ? "0x%p  " : "  %p  ", data);
657 
658 			if (desc->irq_data.domain && desc->irq_data.domain->of_node)
659 				p = desc->irq_data.domain->of_node->full_name;
660 			else
661 				p = none;
662 			seq_printf(m, "%s\n", p);
663 		}
664 
665 		raw_spin_unlock_irqrestore(&desc->lock, flags);
666 	}
667 
668 	return 0;
669 }
670 
671 static int virq_debug_open(struct inode *inode, struct file *file)
672 {
673 	return single_open(file, virq_debug_show, inode->i_private);
674 }
675 
676 static const struct file_operations virq_debug_fops = {
677 	.open = virq_debug_open,
678 	.read = seq_read,
679 	.llseek = seq_lseek,
680 	.release = single_release,
681 };
682 
683 static int __init irq_debugfs_init(void)
684 {
685 	if (debugfs_create_file("irq_domain_mapping", S_IRUGO, NULL,
686 				 NULL, &virq_debug_fops) == NULL)
687 		return -ENOMEM;
688 
689 	return 0;
690 }
691 __initcall(irq_debugfs_init);
692 #endif /* CONFIG_IRQ_DOMAIN_DEBUG */
693 
694 int irq_domain_simple_map(struct irq_domain *d, unsigned int irq,
695 			  irq_hw_number_t hwirq)
696 {
697 	return 0;
698 }
699 
700 /**
701  * irq_domain_xlate_onecell() - Generic xlate for direct one cell bindings
702  *
703  * Device Tree IRQ specifier translation function which works with one cell
704  * bindings where the cell value maps directly to the hwirq number.
705  */
706 int irq_domain_xlate_onecell(struct irq_domain *d, struct device_node *ctrlr,
707 			     const u32 *intspec, unsigned int intsize,
708 			     unsigned long *out_hwirq, unsigned int *out_type)
709 {
710 	if (WARN_ON(intsize < 1))
711 		return -EINVAL;
712 	*out_hwirq = intspec[0];
713 	*out_type = IRQ_TYPE_NONE;
714 	return 0;
715 }
716 EXPORT_SYMBOL_GPL(irq_domain_xlate_onecell);
717 
718 /**
719  * irq_domain_xlate_twocell() - Generic xlate for direct two cell bindings
720  *
721  * Device Tree IRQ specifier translation function which works with two cell
722  * bindings where the cell values map directly to the hwirq number
723  * and linux irq flags.
724  */
725 int irq_domain_xlate_twocell(struct irq_domain *d, struct device_node *ctrlr,
726 			const u32 *intspec, unsigned int intsize,
727 			irq_hw_number_t *out_hwirq, unsigned int *out_type)
728 {
729 	if (WARN_ON(intsize < 2))
730 		return -EINVAL;
731 	*out_hwirq = intspec[0];
732 	*out_type = intspec[1] & IRQ_TYPE_SENSE_MASK;
733 	return 0;
734 }
735 EXPORT_SYMBOL_GPL(irq_domain_xlate_twocell);
736 
737 /**
738  * irq_domain_xlate_onetwocell() - Generic xlate for one or two cell bindings
739  *
740  * Device Tree IRQ specifier translation function which works with either one
741  * or two cell bindings where the cell values map directly to the hwirq number
742  * and linux irq flags.
743  *
744  * Note: don't use this function unless your interrupt controller explicitly
745  * supports both one and two cell bindings.  For the majority of controllers
746  * the _onecell() or _twocell() variants above should be used.
747  */
748 int irq_domain_xlate_onetwocell(struct irq_domain *d,
749 				struct device_node *ctrlr,
750 				const u32 *intspec, unsigned int intsize,
751 				unsigned long *out_hwirq, unsigned int *out_type)
752 {
753 	if (WARN_ON(intsize < 1))
754 		return -EINVAL;
755 	*out_hwirq = intspec[0];
756 	*out_type = (intsize > 1) ? intspec[1] : IRQ_TYPE_NONE;
757 	return 0;
758 }
759 EXPORT_SYMBOL_GPL(irq_domain_xlate_onetwocell);
760 
761 const struct irq_domain_ops irq_domain_simple_ops = {
762 	.map = irq_domain_simple_map,
763 	.xlate = irq_domain_xlate_onetwocell,
764 };
765 EXPORT_SYMBOL_GPL(irq_domain_simple_ops);
766 
767 #ifdef CONFIG_OF_IRQ
768 void irq_domain_generate_simple(const struct of_device_id *match,
769 				u64 phys_base, unsigned int irq_start)
770 {
771 	struct device_node *node;
772 	pr_debug("looking for phys_base=%llx, irq_start=%i\n",
773 		(unsigned long long) phys_base, (int) irq_start);
774 	node = of_find_matching_node_by_address(NULL, match, phys_base);
775 	if (node)
776 		irq_domain_add_legacy(node, 32, irq_start, 0,
777 				      &irq_domain_simple_ops, NULL);
778 }
779 EXPORT_SYMBOL_GPL(irq_domain_generate_simple);
780 #endif
781