xref: /openbmc/linux/kernel/irq/irqdomain.c (revision 6562c9ac)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 #define pr_fmt(fmt)  "irq: " fmt
4 
5 #include <linux/acpi.h>
6 #include <linux/debugfs.h>
7 #include <linux/hardirq.h>
8 #include <linux/interrupt.h>
9 #include <linux/irq.h>
10 #include <linux/irqdesc.h>
11 #include <linux/irqdomain.h>
12 #include <linux/module.h>
13 #include <linux/mutex.h>
14 #include <linux/of.h>
15 #include <linux/of_address.h>
16 #include <linux/of_irq.h>
17 #include <linux/topology.h>
18 #include <linux/seq_file.h>
19 #include <linux/slab.h>
20 #include <linux/smp.h>
21 #include <linux/fs.h>
22 
23 static LIST_HEAD(irq_domain_list);
24 static DEFINE_MUTEX(irq_domain_mutex);
25 
26 static struct irq_domain *irq_default_domain;
27 
28 static void irq_domain_check_hierarchy(struct irq_domain *domain);
29 
30 struct irqchip_fwid {
31 	struct fwnode_handle	fwnode;
32 	unsigned int		type;
33 	char			*name;
34 	phys_addr_t		*pa;
35 };
36 
37 #ifdef CONFIG_GENERIC_IRQ_DEBUGFS
38 static void debugfs_add_domain_dir(struct irq_domain *d);
39 static void debugfs_remove_domain_dir(struct irq_domain *d);
40 #else
41 static inline void debugfs_add_domain_dir(struct irq_domain *d) { }
42 static inline void debugfs_remove_domain_dir(struct irq_domain *d) { }
43 #endif
44 
45 static const char *irqchip_fwnode_get_name(const struct fwnode_handle *fwnode)
46 {
47 	struct irqchip_fwid *fwid = container_of(fwnode, struct irqchip_fwid, fwnode);
48 
49 	return fwid->name;
50 }
51 
52 const struct fwnode_operations irqchip_fwnode_ops = {
53 	.get_name = irqchip_fwnode_get_name,
54 };
55 EXPORT_SYMBOL_GPL(irqchip_fwnode_ops);
56 
57 /**
58  * __irq_domain_alloc_fwnode - Allocate a fwnode_handle suitable for
59  *                           identifying an irq domain
60  * @type:	Type of irqchip_fwnode. See linux/irqdomain.h
61  * @id:		Optional user provided id if name != NULL
62  * @name:	Optional user provided domain name
63  * @pa:		Optional user-provided physical address
64  *
65  * Allocate a struct irqchip_fwid, and return a pointer to the embedded
66  * fwnode_handle (or NULL on failure).
67  *
68  * Note: The types IRQCHIP_FWNODE_NAMED and IRQCHIP_FWNODE_NAMED_ID are
69  * solely to transport name information to irqdomain creation code. The
70  * node is not stored. For other types the pointer is kept in the irq
71  * domain struct.
72  */
73 struct fwnode_handle *__irq_domain_alloc_fwnode(unsigned int type, int id,
74 						const char *name,
75 						phys_addr_t *pa)
76 {
77 	struct irqchip_fwid *fwid;
78 	char *n;
79 
80 	fwid = kzalloc(sizeof(*fwid), GFP_KERNEL);
81 
82 	switch (type) {
83 	case IRQCHIP_FWNODE_NAMED:
84 		n = kasprintf(GFP_KERNEL, "%s", name);
85 		break;
86 	case IRQCHIP_FWNODE_NAMED_ID:
87 		n = kasprintf(GFP_KERNEL, "%s-%d", name, id);
88 		break;
89 	default:
90 		n = kasprintf(GFP_KERNEL, "irqchip@%pa", pa);
91 		break;
92 	}
93 
94 	if (!fwid || !n) {
95 		kfree(fwid);
96 		kfree(n);
97 		return NULL;
98 	}
99 
100 	fwid->type = type;
101 	fwid->name = n;
102 	fwid->pa = pa;
103 	fwnode_init(&fwid->fwnode, &irqchip_fwnode_ops);
104 	return &fwid->fwnode;
105 }
106 EXPORT_SYMBOL_GPL(__irq_domain_alloc_fwnode);
107 
108 /**
109  * irq_domain_free_fwnode - Free a non-OF-backed fwnode_handle
110  *
111  * Free a fwnode_handle allocated with irq_domain_alloc_fwnode.
112  */
113 void irq_domain_free_fwnode(struct fwnode_handle *fwnode)
114 {
115 	struct irqchip_fwid *fwid;
116 
117 	if (WARN_ON(!is_fwnode_irqchip(fwnode)))
118 		return;
119 
120 	fwid = container_of(fwnode, struct irqchip_fwid, fwnode);
121 	kfree(fwid->name);
122 	kfree(fwid);
123 }
124 EXPORT_SYMBOL_GPL(irq_domain_free_fwnode);
125 
126 /**
127  * __irq_domain_add() - Allocate a new irq_domain data structure
128  * @fwnode: firmware node for the interrupt controller
129  * @size: Size of linear map; 0 for radix mapping only
130  * @hwirq_max: Maximum number of interrupts supported by controller
131  * @direct_max: Maximum value of direct maps; Use ~0 for no limit; 0 for no
132  *              direct mapping
133  * @ops: domain callbacks
134  * @host_data: Controller private data pointer
135  *
136  * Allocates and initializes an irq_domain structure.
137  * Returns pointer to IRQ domain, or NULL on failure.
138  */
139 struct irq_domain *__irq_domain_add(struct fwnode_handle *fwnode, unsigned int size,
140 				    irq_hw_number_t hwirq_max, int direct_max,
141 				    const struct irq_domain_ops *ops,
142 				    void *host_data)
143 {
144 	struct irqchip_fwid *fwid;
145 	struct irq_domain *domain;
146 
147 	static atomic_t unknown_domains;
148 
149 	if (WARN_ON((size && direct_max) ||
150 		    (!IS_ENABLED(CONFIG_IRQ_DOMAIN_NOMAP) && direct_max) ||
151 		    (direct_max && (direct_max != hwirq_max))))
152 		return NULL;
153 
154 	domain = kzalloc_node(struct_size(domain, revmap, size),
155 			      GFP_KERNEL, of_node_to_nid(to_of_node(fwnode)));
156 	if (!domain)
157 		return NULL;
158 
159 	if (is_fwnode_irqchip(fwnode)) {
160 		fwid = container_of(fwnode, struct irqchip_fwid, fwnode);
161 
162 		switch (fwid->type) {
163 		case IRQCHIP_FWNODE_NAMED:
164 		case IRQCHIP_FWNODE_NAMED_ID:
165 			domain->fwnode = fwnode;
166 			domain->name = kstrdup(fwid->name, GFP_KERNEL);
167 			if (!domain->name) {
168 				kfree(domain);
169 				return NULL;
170 			}
171 			domain->flags |= IRQ_DOMAIN_NAME_ALLOCATED;
172 			break;
173 		default:
174 			domain->fwnode = fwnode;
175 			domain->name = fwid->name;
176 			break;
177 		}
178 	} else if (is_of_node(fwnode) || is_acpi_device_node(fwnode) ||
179 		   is_software_node(fwnode)) {
180 		char *name;
181 
182 		/*
183 		 * fwnode paths contain '/', which debugfs is legitimately
184 		 * unhappy about. Replace them with ':', which does
185 		 * the trick and is not as offensive as '\'...
186 		 */
187 		name = kasprintf(GFP_KERNEL, "%pfw", fwnode);
188 		if (!name) {
189 			kfree(domain);
190 			return NULL;
191 		}
192 
193 		strreplace(name, '/', ':');
194 
195 		domain->name = name;
196 		domain->fwnode = fwnode;
197 		domain->flags |= IRQ_DOMAIN_NAME_ALLOCATED;
198 	}
199 
200 	if (!domain->name) {
201 		if (fwnode)
202 			pr_err("Invalid fwnode type for irqdomain\n");
203 		domain->name = kasprintf(GFP_KERNEL, "unknown-%d",
204 					 atomic_inc_return(&unknown_domains));
205 		if (!domain->name) {
206 			kfree(domain);
207 			return NULL;
208 		}
209 		domain->flags |= IRQ_DOMAIN_NAME_ALLOCATED;
210 	}
211 
212 	fwnode_handle_get(fwnode);
213 	fwnode_dev_initialized(fwnode, true);
214 
215 	/* Fill structure */
216 	INIT_RADIX_TREE(&domain->revmap_tree, GFP_KERNEL);
217 	mutex_init(&domain->revmap_mutex);
218 	domain->ops = ops;
219 	domain->host_data = host_data;
220 	domain->hwirq_max = hwirq_max;
221 
222 	if (direct_max) {
223 		domain->flags |= IRQ_DOMAIN_FLAG_NO_MAP;
224 	}
225 
226 	domain->revmap_size = size;
227 
228 	irq_domain_check_hierarchy(domain);
229 
230 	mutex_lock(&irq_domain_mutex);
231 	debugfs_add_domain_dir(domain);
232 	list_add(&domain->link, &irq_domain_list);
233 	mutex_unlock(&irq_domain_mutex);
234 
235 	pr_debug("Added domain %s\n", domain->name);
236 	return domain;
237 }
238 EXPORT_SYMBOL_GPL(__irq_domain_add);
239 
240 /**
241  * irq_domain_remove() - Remove an irq domain.
242  * @domain: domain to remove
243  *
244  * This routine is used to remove an irq domain. The caller must ensure
245  * that all mappings within the domain have been disposed of prior to
246  * use, depending on the revmap type.
247  */
248 void irq_domain_remove(struct irq_domain *domain)
249 {
250 	mutex_lock(&irq_domain_mutex);
251 	debugfs_remove_domain_dir(domain);
252 
253 	WARN_ON(!radix_tree_empty(&domain->revmap_tree));
254 
255 	list_del(&domain->link);
256 
257 	/*
258 	 * If the going away domain is the default one, reset it.
259 	 */
260 	if (unlikely(irq_default_domain == domain))
261 		irq_set_default_host(NULL);
262 
263 	mutex_unlock(&irq_domain_mutex);
264 
265 	pr_debug("Removed domain %s\n", domain->name);
266 
267 	fwnode_dev_initialized(domain->fwnode, false);
268 	fwnode_handle_put(domain->fwnode);
269 	if (domain->flags & IRQ_DOMAIN_NAME_ALLOCATED)
270 		kfree(domain->name);
271 	kfree(domain);
272 }
273 EXPORT_SYMBOL_GPL(irq_domain_remove);
274 
275 void irq_domain_update_bus_token(struct irq_domain *domain,
276 				 enum irq_domain_bus_token bus_token)
277 {
278 	char *name;
279 
280 	if (domain->bus_token == bus_token)
281 		return;
282 
283 	mutex_lock(&irq_domain_mutex);
284 
285 	domain->bus_token = bus_token;
286 
287 	name = kasprintf(GFP_KERNEL, "%s-%d", domain->name, bus_token);
288 	if (!name) {
289 		mutex_unlock(&irq_domain_mutex);
290 		return;
291 	}
292 
293 	debugfs_remove_domain_dir(domain);
294 
295 	if (domain->flags & IRQ_DOMAIN_NAME_ALLOCATED)
296 		kfree(domain->name);
297 	else
298 		domain->flags |= IRQ_DOMAIN_NAME_ALLOCATED;
299 
300 	domain->name = name;
301 	debugfs_add_domain_dir(domain);
302 
303 	mutex_unlock(&irq_domain_mutex);
304 }
305 EXPORT_SYMBOL_GPL(irq_domain_update_bus_token);
306 
307 /**
308  * irq_domain_create_simple() - Register an irq_domain and optionally map a range of irqs
309  * @fwnode: firmware node for the interrupt controller
310  * @size: total number of irqs in mapping
311  * @first_irq: first number of irq block assigned to the domain,
312  *	pass zero to assign irqs on-the-fly. If first_irq is non-zero, then
313  *	pre-map all of the irqs in the domain to virqs starting at first_irq.
314  * @ops: domain callbacks
315  * @host_data: Controller private data pointer
316  *
317  * Allocates an irq_domain, and optionally if first_irq is positive then also
318  * allocate irq_descs and map all of the hwirqs to virqs starting at first_irq.
319  *
320  * This is intended to implement the expected behaviour for most
321  * interrupt controllers. If device tree is used, then first_irq will be 0 and
322  * irqs get mapped dynamically on the fly. However, if the controller requires
323  * static virq assignments (non-DT boot) then it will set that up correctly.
324  */
325 struct irq_domain *irq_domain_create_simple(struct fwnode_handle *fwnode,
326 					    unsigned int size,
327 					    unsigned int first_irq,
328 					    const struct irq_domain_ops *ops,
329 					    void *host_data)
330 {
331 	struct irq_domain *domain;
332 
333 	domain = __irq_domain_add(fwnode, size, size, 0, ops, host_data);
334 	if (!domain)
335 		return NULL;
336 
337 	if (first_irq > 0) {
338 		if (IS_ENABLED(CONFIG_SPARSE_IRQ)) {
339 			/* attempt to allocated irq_descs */
340 			int rc = irq_alloc_descs(first_irq, first_irq, size,
341 						 of_node_to_nid(to_of_node(fwnode)));
342 			if (rc < 0)
343 				pr_info("Cannot allocate irq_descs @ IRQ%d, assuming pre-allocated\n",
344 					first_irq);
345 		}
346 		irq_domain_associate_many(domain, first_irq, 0, size);
347 	}
348 
349 	return domain;
350 }
351 EXPORT_SYMBOL_GPL(irq_domain_create_simple);
352 
353 /**
354  * irq_domain_add_legacy() - Allocate and register a legacy revmap irq_domain.
355  * @of_node: pointer to interrupt controller's device tree node.
356  * @size: total number of irqs in legacy mapping
357  * @first_irq: first number of irq block assigned to the domain
358  * @first_hwirq: first hwirq number to use for the translation. Should normally
359  *               be '0', but a positive integer can be used if the effective
360  *               hwirqs numbering does not begin at zero.
361  * @ops: map/unmap domain callbacks
362  * @host_data: Controller private data pointer
363  *
364  * Note: the map() callback will be called before this function returns
365  * for all legacy interrupts except 0 (which is always the invalid irq for
366  * a legacy controller).
367  */
368 struct irq_domain *irq_domain_add_legacy(struct device_node *of_node,
369 					 unsigned int size,
370 					 unsigned int first_irq,
371 					 irq_hw_number_t first_hwirq,
372 					 const struct irq_domain_ops *ops,
373 					 void *host_data)
374 {
375 	return irq_domain_create_legacy(of_node_to_fwnode(of_node), size,
376 					first_irq, first_hwirq, ops, host_data);
377 }
378 EXPORT_SYMBOL_GPL(irq_domain_add_legacy);
379 
380 struct irq_domain *irq_domain_create_legacy(struct fwnode_handle *fwnode,
381 					 unsigned int size,
382 					 unsigned int first_irq,
383 					 irq_hw_number_t first_hwirq,
384 					 const struct irq_domain_ops *ops,
385 					 void *host_data)
386 {
387 	struct irq_domain *domain;
388 
389 	domain = __irq_domain_add(fwnode, first_hwirq + size, first_hwirq + size, 0, ops, host_data);
390 	if (domain)
391 		irq_domain_associate_many(domain, first_irq, first_hwirq, size);
392 
393 	return domain;
394 }
395 EXPORT_SYMBOL_GPL(irq_domain_create_legacy);
396 
397 /**
398  * irq_find_matching_fwspec() - Locates a domain for a given fwspec
399  * @fwspec: FW specifier for an interrupt
400  * @bus_token: domain-specific data
401  */
402 struct irq_domain *irq_find_matching_fwspec(struct irq_fwspec *fwspec,
403 					    enum irq_domain_bus_token bus_token)
404 {
405 	struct irq_domain *h, *found = NULL;
406 	struct fwnode_handle *fwnode = fwspec->fwnode;
407 	int rc;
408 
409 	/* We might want to match the legacy controller last since
410 	 * it might potentially be set to match all interrupts in
411 	 * the absence of a device node. This isn't a problem so far
412 	 * yet though...
413 	 *
414 	 * bus_token == DOMAIN_BUS_ANY matches any domain, any other
415 	 * values must generate an exact match for the domain to be
416 	 * selected.
417 	 */
418 	mutex_lock(&irq_domain_mutex);
419 	list_for_each_entry(h, &irq_domain_list, link) {
420 		if (h->ops->select && fwspec->param_count)
421 			rc = h->ops->select(h, fwspec, bus_token);
422 		else if (h->ops->match)
423 			rc = h->ops->match(h, to_of_node(fwnode), bus_token);
424 		else
425 			rc = ((fwnode != NULL) && (h->fwnode == fwnode) &&
426 			      ((bus_token == DOMAIN_BUS_ANY) ||
427 			       (h->bus_token == bus_token)));
428 
429 		if (rc) {
430 			found = h;
431 			break;
432 		}
433 	}
434 	mutex_unlock(&irq_domain_mutex);
435 	return found;
436 }
437 EXPORT_SYMBOL_GPL(irq_find_matching_fwspec);
438 
439 /**
440  * irq_domain_check_msi_remap - Check whether all MSI irq domains implement
441  * IRQ remapping
442  *
443  * Return: false if any MSI irq domain does not support IRQ remapping,
444  * true otherwise (including if there is no MSI irq domain)
445  */
446 bool irq_domain_check_msi_remap(void)
447 {
448 	struct irq_domain *h;
449 	bool ret = true;
450 
451 	mutex_lock(&irq_domain_mutex);
452 	list_for_each_entry(h, &irq_domain_list, link) {
453 		if (irq_domain_is_msi(h) &&
454 		    !irq_domain_hierarchical_is_msi_remap(h)) {
455 			ret = false;
456 			break;
457 		}
458 	}
459 	mutex_unlock(&irq_domain_mutex);
460 	return ret;
461 }
462 EXPORT_SYMBOL_GPL(irq_domain_check_msi_remap);
463 
464 /**
465  * irq_set_default_host() - Set a "default" irq domain
466  * @domain: default domain pointer
467  *
468  * For convenience, it's possible to set a "default" domain that will be used
469  * whenever NULL is passed to irq_create_mapping(). It makes life easier for
470  * platforms that want to manipulate a few hard coded interrupt numbers that
471  * aren't properly represented in the device-tree.
472  */
473 void irq_set_default_host(struct irq_domain *domain)
474 {
475 	pr_debug("Default domain set to @0x%p\n", domain);
476 
477 	irq_default_domain = domain;
478 }
479 EXPORT_SYMBOL_GPL(irq_set_default_host);
480 
481 /**
482  * irq_get_default_host() - Retrieve the "default" irq domain
483  *
484  * Returns: the default domain, if any.
485  *
486  * Modern code should never use this. This should only be used on
487  * systems that cannot implement a firmware->fwnode mapping (which
488  * both DT and ACPI provide).
489  */
490 struct irq_domain *irq_get_default_host(void)
491 {
492 	return irq_default_domain;
493 }
494 EXPORT_SYMBOL_GPL(irq_get_default_host);
495 
496 static bool irq_domain_is_nomap(struct irq_domain *domain)
497 {
498 	return IS_ENABLED(CONFIG_IRQ_DOMAIN_NOMAP) &&
499 	       (domain->flags & IRQ_DOMAIN_FLAG_NO_MAP);
500 }
501 
502 static void irq_domain_clear_mapping(struct irq_domain *domain,
503 				     irq_hw_number_t hwirq)
504 {
505 	if (irq_domain_is_nomap(domain))
506 		return;
507 
508 	mutex_lock(&domain->revmap_mutex);
509 	if (hwirq < domain->revmap_size)
510 		rcu_assign_pointer(domain->revmap[hwirq], NULL);
511 	else
512 		radix_tree_delete(&domain->revmap_tree, hwirq);
513 	mutex_unlock(&domain->revmap_mutex);
514 }
515 
516 static void irq_domain_set_mapping(struct irq_domain *domain,
517 				   irq_hw_number_t hwirq,
518 				   struct irq_data *irq_data)
519 {
520 	if (irq_domain_is_nomap(domain))
521 		return;
522 
523 	mutex_lock(&domain->revmap_mutex);
524 	if (hwirq < domain->revmap_size)
525 		rcu_assign_pointer(domain->revmap[hwirq], irq_data);
526 	else
527 		radix_tree_insert(&domain->revmap_tree, hwirq, irq_data);
528 	mutex_unlock(&domain->revmap_mutex);
529 }
530 
531 static void irq_domain_disassociate(struct irq_domain *domain, unsigned int irq)
532 {
533 	struct irq_data *irq_data = irq_get_irq_data(irq);
534 	irq_hw_number_t hwirq;
535 
536 	if (WARN(!irq_data || irq_data->domain != domain,
537 		 "virq%i doesn't exist; cannot disassociate\n", irq))
538 		return;
539 
540 	hwirq = irq_data->hwirq;
541 	irq_set_status_flags(irq, IRQ_NOREQUEST);
542 
543 	/* remove chip and handler */
544 	irq_set_chip_and_handler(irq, NULL, NULL);
545 
546 	/* Make sure it's completed */
547 	synchronize_irq(irq);
548 
549 	/* Tell the PIC about it */
550 	if (domain->ops->unmap)
551 		domain->ops->unmap(domain, irq);
552 	smp_mb();
553 
554 	irq_data->domain = NULL;
555 	irq_data->hwirq = 0;
556 	domain->mapcount--;
557 
558 	/* Clear reverse map for this hwirq */
559 	irq_domain_clear_mapping(domain, hwirq);
560 }
561 
562 int irq_domain_associate(struct irq_domain *domain, unsigned int virq,
563 			 irq_hw_number_t hwirq)
564 {
565 	struct irq_data *irq_data = irq_get_irq_data(virq);
566 	int ret;
567 
568 	if (WARN(hwirq >= domain->hwirq_max,
569 		 "error: hwirq 0x%x is too large for %s\n", (int)hwirq, domain->name))
570 		return -EINVAL;
571 	if (WARN(!irq_data, "error: virq%i is not allocated", virq))
572 		return -EINVAL;
573 	if (WARN(irq_data->domain, "error: virq%i is already associated", virq))
574 		return -EINVAL;
575 
576 	mutex_lock(&irq_domain_mutex);
577 	irq_data->hwirq = hwirq;
578 	irq_data->domain = domain;
579 	if (domain->ops->map) {
580 		ret = domain->ops->map(domain, virq, hwirq);
581 		if (ret != 0) {
582 			/*
583 			 * If map() returns -EPERM, this interrupt is protected
584 			 * by the firmware or some other service and shall not
585 			 * be mapped. Don't bother telling the user about it.
586 			 */
587 			if (ret != -EPERM) {
588 				pr_info("%s didn't like hwirq-0x%lx to VIRQ%i mapping (rc=%d)\n",
589 				       domain->name, hwirq, virq, ret);
590 			}
591 			irq_data->domain = NULL;
592 			irq_data->hwirq = 0;
593 			mutex_unlock(&irq_domain_mutex);
594 			return ret;
595 		}
596 
597 		/* If not already assigned, give the domain the chip's name */
598 		if (!domain->name && irq_data->chip)
599 			domain->name = irq_data->chip->name;
600 	}
601 
602 	domain->mapcount++;
603 	irq_domain_set_mapping(domain, hwirq, irq_data);
604 	mutex_unlock(&irq_domain_mutex);
605 
606 	irq_clear_status_flags(virq, IRQ_NOREQUEST);
607 
608 	return 0;
609 }
610 EXPORT_SYMBOL_GPL(irq_domain_associate);
611 
612 void irq_domain_associate_many(struct irq_domain *domain, unsigned int irq_base,
613 			       irq_hw_number_t hwirq_base, int count)
614 {
615 	struct device_node *of_node;
616 	int i;
617 
618 	of_node = irq_domain_get_of_node(domain);
619 	pr_debug("%s(%s, irqbase=%i, hwbase=%i, count=%i)\n", __func__,
620 		of_node_full_name(of_node), irq_base, (int)hwirq_base, count);
621 
622 	for (i = 0; i < count; i++) {
623 		irq_domain_associate(domain, irq_base + i, hwirq_base + i);
624 	}
625 }
626 EXPORT_SYMBOL_GPL(irq_domain_associate_many);
627 
628 #ifdef CONFIG_IRQ_DOMAIN_NOMAP
629 /**
630  * irq_create_direct_mapping() - Allocate an irq for direct mapping
631  * @domain: domain to allocate the irq for or NULL for default domain
632  *
633  * This routine is used for irq controllers which can choose the hardware
634  * interrupt numbers they generate. In such a case it's simplest to use
635  * the linux irq as the hardware interrupt number. It still uses the linear
636  * or radix tree to store the mapping, but the irq controller can optimize
637  * the revmap path by using the hwirq directly.
638  */
639 unsigned int irq_create_direct_mapping(struct irq_domain *domain)
640 {
641 	struct device_node *of_node;
642 	unsigned int virq;
643 
644 	if (domain == NULL)
645 		domain = irq_default_domain;
646 
647 	of_node = irq_domain_get_of_node(domain);
648 	virq = irq_alloc_desc_from(1, of_node_to_nid(of_node));
649 	if (!virq) {
650 		pr_debug("create_direct virq allocation failed\n");
651 		return 0;
652 	}
653 	if (virq >= domain->hwirq_max) {
654 		pr_err("ERROR: no free irqs available below %lu maximum\n",
655 			domain->hwirq_max);
656 		irq_free_desc(virq);
657 		return 0;
658 	}
659 	pr_debug("create_direct obtained virq %d\n", virq);
660 
661 	if (irq_domain_associate(domain, virq, virq)) {
662 		irq_free_desc(virq);
663 		return 0;
664 	}
665 
666 	return virq;
667 }
668 EXPORT_SYMBOL_GPL(irq_create_direct_mapping);
669 #endif
670 
671 /**
672  * irq_create_mapping_affinity() - Map a hardware interrupt into linux irq space
673  * @domain: domain owning this hardware interrupt or NULL for default domain
674  * @hwirq: hardware irq number in that domain space
675  * @affinity: irq affinity
676  *
677  * Only one mapping per hardware interrupt is permitted. Returns a linux
678  * irq number.
679  * If the sense/trigger is to be specified, set_irq_type() should be called
680  * on the number returned from that call.
681  */
682 unsigned int irq_create_mapping_affinity(struct irq_domain *domain,
683 				       irq_hw_number_t hwirq,
684 				       const struct irq_affinity_desc *affinity)
685 {
686 	struct device_node *of_node;
687 	int virq;
688 
689 	pr_debug("irq_create_mapping(0x%p, 0x%lx)\n", domain, hwirq);
690 
691 	/* Look for default domain if necessary */
692 	if (domain == NULL)
693 		domain = irq_default_domain;
694 	if (domain == NULL) {
695 		WARN(1, "%s(, %lx) called with NULL domain\n", __func__, hwirq);
696 		return 0;
697 	}
698 	pr_debug("-> using domain @%p\n", domain);
699 
700 	of_node = irq_domain_get_of_node(domain);
701 
702 	/* Check if mapping already exists */
703 	virq = irq_find_mapping(domain, hwirq);
704 	if (virq) {
705 		pr_debug("-> existing mapping on virq %d\n", virq);
706 		return virq;
707 	}
708 
709 	/* Allocate a virtual interrupt number */
710 	virq = irq_domain_alloc_descs(-1, 1, hwirq, of_node_to_nid(of_node),
711 				      affinity);
712 	if (virq <= 0) {
713 		pr_debug("-> virq allocation failed\n");
714 		return 0;
715 	}
716 
717 	if (irq_domain_associate(domain, virq, hwirq)) {
718 		irq_free_desc(virq);
719 		return 0;
720 	}
721 
722 	pr_debug("irq %lu on domain %s mapped to virtual irq %u\n",
723 		hwirq, of_node_full_name(of_node), virq);
724 
725 	return virq;
726 }
727 EXPORT_SYMBOL_GPL(irq_create_mapping_affinity);
728 
729 static int irq_domain_translate(struct irq_domain *d,
730 				struct irq_fwspec *fwspec,
731 				irq_hw_number_t *hwirq, unsigned int *type)
732 {
733 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
734 	if (d->ops->translate)
735 		return d->ops->translate(d, fwspec, hwirq, type);
736 #endif
737 	if (d->ops->xlate)
738 		return d->ops->xlate(d, to_of_node(fwspec->fwnode),
739 				     fwspec->param, fwspec->param_count,
740 				     hwirq, type);
741 
742 	/* If domain has no translation, then we assume interrupt line */
743 	*hwirq = fwspec->param[0];
744 	return 0;
745 }
746 
747 void of_phandle_args_to_fwspec(struct device_node *np, const u32 *args,
748 			       unsigned int count, struct irq_fwspec *fwspec)
749 {
750 	int i;
751 
752 	fwspec->fwnode = of_node_to_fwnode(np);
753 	fwspec->param_count = count;
754 
755 	for (i = 0; i < count; i++)
756 		fwspec->param[i] = args[i];
757 }
758 EXPORT_SYMBOL_GPL(of_phandle_args_to_fwspec);
759 
760 unsigned int irq_create_fwspec_mapping(struct irq_fwspec *fwspec)
761 {
762 	struct irq_domain *domain;
763 	struct irq_data *irq_data;
764 	irq_hw_number_t hwirq;
765 	unsigned int type = IRQ_TYPE_NONE;
766 	int virq;
767 
768 	if (fwspec->fwnode) {
769 		domain = irq_find_matching_fwspec(fwspec, DOMAIN_BUS_WIRED);
770 		if (!domain)
771 			domain = irq_find_matching_fwspec(fwspec, DOMAIN_BUS_ANY);
772 	} else {
773 		domain = irq_default_domain;
774 	}
775 
776 	if (!domain) {
777 		pr_warn("no irq domain found for %s !\n",
778 			of_node_full_name(to_of_node(fwspec->fwnode)));
779 		return 0;
780 	}
781 
782 	if (irq_domain_translate(domain, fwspec, &hwirq, &type))
783 		return 0;
784 
785 	/*
786 	 * WARN if the irqchip returns a type with bits
787 	 * outside the sense mask set and clear these bits.
788 	 */
789 	if (WARN_ON(type & ~IRQ_TYPE_SENSE_MASK))
790 		type &= IRQ_TYPE_SENSE_MASK;
791 
792 	/*
793 	 * If we've already configured this interrupt,
794 	 * don't do it again, or hell will break loose.
795 	 */
796 	virq = irq_find_mapping(domain, hwirq);
797 	if (virq) {
798 		/*
799 		 * If the trigger type is not specified or matches the
800 		 * current trigger type then we are done so return the
801 		 * interrupt number.
802 		 */
803 		if (type == IRQ_TYPE_NONE || type == irq_get_trigger_type(virq))
804 			return virq;
805 
806 		/*
807 		 * If the trigger type has not been set yet, then set
808 		 * it now and return the interrupt number.
809 		 */
810 		if (irq_get_trigger_type(virq) == IRQ_TYPE_NONE) {
811 			irq_data = irq_get_irq_data(virq);
812 			if (!irq_data)
813 				return 0;
814 
815 			irqd_set_trigger_type(irq_data, type);
816 			return virq;
817 		}
818 
819 		pr_warn("type mismatch, failed to map hwirq-%lu for %s!\n",
820 			hwirq, of_node_full_name(to_of_node(fwspec->fwnode)));
821 		return 0;
822 	}
823 
824 	if (irq_domain_is_hierarchy(domain)) {
825 		virq = irq_domain_alloc_irqs(domain, 1, NUMA_NO_NODE, fwspec);
826 		if (virq <= 0)
827 			return 0;
828 	} else {
829 		/* Create mapping */
830 		virq = irq_create_mapping(domain, hwirq);
831 		if (!virq)
832 			return virq;
833 	}
834 
835 	irq_data = irq_get_irq_data(virq);
836 	if (!irq_data) {
837 		if (irq_domain_is_hierarchy(domain))
838 			irq_domain_free_irqs(virq, 1);
839 		else
840 			irq_dispose_mapping(virq);
841 		return 0;
842 	}
843 
844 	/* Store trigger type */
845 	irqd_set_trigger_type(irq_data, type);
846 
847 	return virq;
848 }
849 EXPORT_SYMBOL_GPL(irq_create_fwspec_mapping);
850 
851 unsigned int irq_create_of_mapping(struct of_phandle_args *irq_data)
852 {
853 	struct irq_fwspec fwspec;
854 
855 	of_phandle_args_to_fwspec(irq_data->np, irq_data->args,
856 				  irq_data->args_count, &fwspec);
857 
858 	return irq_create_fwspec_mapping(&fwspec);
859 }
860 EXPORT_SYMBOL_GPL(irq_create_of_mapping);
861 
862 /**
863  * irq_dispose_mapping() - Unmap an interrupt
864  * @virq: linux irq number of the interrupt to unmap
865  */
866 void irq_dispose_mapping(unsigned int virq)
867 {
868 	struct irq_data *irq_data = irq_get_irq_data(virq);
869 	struct irq_domain *domain;
870 
871 	if (!virq || !irq_data)
872 		return;
873 
874 	domain = irq_data->domain;
875 	if (WARN_ON(domain == NULL))
876 		return;
877 
878 	if (irq_domain_is_hierarchy(domain)) {
879 		irq_domain_free_irqs(virq, 1);
880 	} else {
881 		irq_domain_disassociate(domain, virq);
882 		irq_free_desc(virq);
883 	}
884 }
885 EXPORT_SYMBOL_GPL(irq_dispose_mapping);
886 
887 /**
888  * __irq_resolve_mapping() - Find a linux irq from a hw irq number.
889  * @domain: domain owning this hardware interrupt
890  * @hwirq: hardware irq number in that domain space
891  * @irq: optional pointer to return the Linux irq if required
892  *
893  * Returns the interrupt descriptor.
894  */
895 struct irq_desc *__irq_resolve_mapping(struct irq_domain *domain,
896 				       irq_hw_number_t hwirq,
897 				       unsigned int *irq)
898 {
899 	struct irq_desc *desc = NULL;
900 	struct irq_data *data;
901 
902 	/* Look for default domain if necessary */
903 	if (domain == NULL)
904 		domain = irq_default_domain;
905 	if (domain == NULL)
906 		return desc;
907 
908 	if (irq_domain_is_nomap(domain)) {
909 		if (hwirq < domain->hwirq_max) {
910 			data = irq_domain_get_irq_data(domain, hwirq);
911 			if (data && data->hwirq == hwirq)
912 				desc = irq_data_to_desc(data);
913 			if (irq && desc)
914 				*irq = hwirq;
915 		}
916 
917 		return desc;
918 	}
919 
920 	rcu_read_lock();
921 	/* Check if the hwirq is in the linear revmap. */
922 	if (hwirq < domain->revmap_size)
923 		data = rcu_dereference(domain->revmap[hwirq]);
924 	else
925 		data = radix_tree_lookup(&domain->revmap_tree, hwirq);
926 
927 	if (likely(data)) {
928 		desc = irq_data_to_desc(data);
929 		if (irq)
930 			*irq = data->irq;
931 	}
932 
933 	rcu_read_unlock();
934 	return desc;
935 }
936 EXPORT_SYMBOL_GPL(__irq_resolve_mapping);
937 
938 /**
939  * irq_domain_xlate_onecell() - Generic xlate for direct one cell bindings
940  *
941  * Device Tree IRQ specifier translation function which works with one cell
942  * bindings where the cell value maps directly to the hwirq number.
943  */
944 int irq_domain_xlate_onecell(struct irq_domain *d, struct device_node *ctrlr,
945 			     const u32 *intspec, unsigned int intsize,
946 			     unsigned long *out_hwirq, unsigned int *out_type)
947 {
948 	if (WARN_ON(intsize < 1))
949 		return -EINVAL;
950 	*out_hwirq = intspec[0];
951 	*out_type = IRQ_TYPE_NONE;
952 	return 0;
953 }
954 EXPORT_SYMBOL_GPL(irq_domain_xlate_onecell);
955 
956 /**
957  * irq_domain_xlate_twocell() - Generic xlate for direct two cell bindings
958  *
959  * Device Tree IRQ specifier translation function which works with two cell
960  * bindings where the cell values map directly to the hwirq number
961  * and linux irq flags.
962  */
963 int irq_domain_xlate_twocell(struct irq_domain *d, struct device_node *ctrlr,
964 			const u32 *intspec, unsigned int intsize,
965 			irq_hw_number_t *out_hwirq, unsigned int *out_type)
966 {
967 	struct irq_fwspec fwspec;
968 
969 	of_phandle_args_to_fwspec(ctrlr, intspec, intsize, &fwspec);
970 	return irq_domain_translate_twocell(d, &fwspec, out_hwirq, out_type);
971 }
972 EXPORT_SYMBOL_GPL(irq_domain_xlate_twocell);
973 
974 /**
975  * irq_domain_xlate_onetwocell() - Generic xlate for one or two cell bindings
976  *
977  * Device Tree IRQ specifier translation function which works with either one
978  * or two cell bindings where the cell values map directly to the hwirq number
979  * and linux irq flags.
980  *
981  * Note: don't use this function unless your interrupt controller explicitly
982  * supports both one and two cell bindings.  For the majority of controllers
983  * the _onecell() or _twocell() variants above should be used.
984  */
985 int irq_domain_xlate_onetwocell(struct irq_domain *d,
986 				struct device_node *ctrlr,
987 				const u32 *intspec, unsigned int intsize,
988 				unsigned long *out_hwirq, unsigned int *out_type)
989 {
990 	if (WARN_ON(intsize < 1))
991 		return -EINVAL;
992 	*out_hwirq = intspec[0];
993 	if (intsize > 1)
994 		*out_type = intspec[1] & IRQ_TYPE_SENSE_MASK;
995 	else
996 		*out_type = IRQ_TYPE_NONE;
997 	return 0;
998 }
999 EXPORT_SYMBOL_GPL(irq_domain_xlate_onetwocell);
1000 
1001 const struct irq_domain_ops irq_domain_simple_ops = {
1002 	.xlate = irq_domain_xlate_onetwocell,
1003 };
1004 EXPORT_SYMBOL_GPL(irq_domain_simple_ops);
1005 
1006 /**
1007  * irq_domain_translate_onecell() - Generic translate for direct one cell
1008  * bindings
1009  */
1010 int irq_domain_translate_onecell(struct irq_domain *d,
1011 				 struct irq_fwspec *fwspec,
1012 				 unsigned long *out_hwirq,
1013 				 unsigned int *out_type)
1014 {
1015 	if (WARN_ON(fwspec->param_count < 1))
1016 		return -EINVAL;
1017 	*out_hwirq = fwspec->param[0];
1018 	*out_type = IRQ_TYPE_NONE;
1019 	return 0;
1020 }
1021 EXPORT_SYMBOL_GPL(irq_domain_translate_onecell);
1022 
1023 /**
1024  * irq_domain_translate_twocell() - Generic translate for direct two cell
1025  * bindings
1026  *
1027  * Device Tree IRQ specifier translation function which works with two cell
1028  * bindings where the cell values map directly to the hwirq number
1029  * and linux irq flags.
1030  */
1031 int irq_domain_translate_twocell(struct irq_domain *d,
1032 				 struct irq_fwspec *fwspec,
1033 				 unsigned long *out_hwirq,
1034 				 unsigned int *out_type)
1035 {
1036 	if (WARN_ON(fwspec->param_count < 2))
1037 		return -EINVAL;
1038 	*out_hwirq = fwspec->param[0];
1039 	*out_type = fwspec->param[1] & IRQ_TYPE_SENSE_MASK;
1040 	return 0;
1041 }
1042 EXPORT_SYMBOL_GPL(irq_domain_translate_twocell);
1043 
1044 int irq_domain_alloc_descs(int virq, unsigned int cnt, irq_hw_number_t hwirq,
1045 			   int node, const struct irq_affinity_desc *affinity)
1046 {
1047 	unsigned int hint;
1048 
1049 	if (virq >= 0) {
1050 		virq = __irq_alloc_descs(virq, virq, cnt, node, THIS_MODULE,
1051 					 affinity);
1052 	} else {
1053 		hint = hwirq % nr_irqs;
1054 		if (hint == 0)
1055 			hint++;
1056 		virq = __irq_alloc_descs(-1, hint, cnt, node, THIS_MODULE,
1057 					 affinity);
1058 		if (virq <= 0 && hint > 1) {
1059 			virq = __irq_alloc_descs(-1, 1, cnt, node, THIS_MODULE,
1060 						 affinity);
1061 		}
1062 	}
1063 
1064 	return virq;
1065 }
1066 
1067 /**
1068  * irq_domain_reset_irq_data - Clear hwirq, chip and chip_data in @irq_data
1069  * @irq_data:	The pointer to irq_data
1070  */
1071 void irq_domain_reset_irq_data(struct irq_data *irq_data)
1072 {
1073 	irq_data->hwirq = 0;
1074 	irq_data->chip = &no_irq_chip;
1075 	irq_data->chip_data = NULL;
1076 }
1077 EXPORT_SYMBOL_GPL(irq_domain_reset_irq_data);
1078 
1079 #ifdef	CONFIG_IRQ_DOMAIN_HIERARCHY
1080 /**
1081  * irq_domain_create_hierarchy - Add a irqdomain into the hierarchy
1082  * @parent:	Parent irq domain to associate with the new domain
1083  * @flags:	Irq domain flags associated to the domain
1084  * @size:	Size of the domain. See below
1085  * @fwnode:	Optional fwnode of the interrupt controller
1086  * @ops:	Pointer to the interrupt domain callbacks
1087  * @host_data:	Controller private data pointer
1088  *
1089  * If @size is 0 a tree domain is created, otherwise a linear domain.
1090  *
1091  * If successful the parent is associated to the new domain and the
1092  * domain flags are set.
1093  * Returns pointer to IRQ domain, or NULL on failure.
1094  */
1095 struct irq_domain *irq_domain_create_hierarchy(struct irq_domain *parent,
1096 					    unsigned int flags,
1097 					    unsigned int size,
1098 					    struct fwnode_handle *fwnode,
1099 					    const struct irq_domain_ops *ops,
1100 					    void *host_data)
1101 {
1102 	struct irq_domain *domain;
1103 
1104 	if (size)
1105 		domain = irq_domain_create_linear(fwnode, size, ops, host_data);
1106 	else
1107 		domain = irq_domain_create_tree(fwnode, ops, host_data);
1108 	if (domain) {
1109 		domain->parent = parent;
1110 		domain->flags |= flags;
1111 	}
1112 
1113 	return domain;
1114 }
1115 EXPORT_SYMBOL_GPL(irq_domain_create_hierarchy);
1116 
1117 static void irq_domain_insert_irq(int virq)
1118 {
1119 	struct irq_data *data;
1120 
1121 	for (data = irq_get_irq_data(virq); data; data = data->parent_data) {
1122 		struct irq_domain *domain = data->domain;
1123 
1124 		domain->mapcount++;
1125 		irq_domain_set_mapping(domain, data->hwirq, data);
1126 
1127 		/* If not already assigned, give the domain the chip's name */
1128 		if (!domain->name && data->chip)
1129 			domain->name = data->chip->name;
1130 	}
1131 
1132 	irq_clear_status_flags(virq, IRQ_NOREQUEST);
1133 }
1134 
1135 static void irq_domain_remove_irq(int virq)
1136 {
1137 	struct irq_data *data;
1138 
1139 	irq_set_status_flags(virq, IRQ_NOREQUEST);
1140 	irq_set_chip_and_handler(virq, NULL, NULL);
1141 	synchronize_irq(virq);
1142 	smp_mb();
1143 
1144 	for (data = irq_get_irq_data(virq); data; data = data->parent_data) {
1145 		struct irq_domain *domain = data->domain;
1146 		irq_hw_number_t hwirq = data->hwirq;
1147 
1148 		domain->mapcount--;
1149 		irq_domain_clear_mapping(domain, hwirq);
1150 	}
1151 }
1152 
1153 static struct irq_data *irq_domain_insert_irq_data(struct irq_domain *domain,
1154 						   struct irq_data *child)
1155 {
1156 	struct irq_data *irq_data;
1157 
1158 	irq_data = kzalloc_node(sizeof(*irq_data), GFP_KERNEL,
1159 				irq_data_get_node(child));
1160 	if (irq_data) {
1161 		child->parent_data = irq_data;
1162 		irq_data->irq = child->irq;
1163 		irq_data->common = child->common;
1164 		irq_data->domain = domain;
1165 	}
1166 
1167 	return irq_data;
1168 }
1169 
1170 static void __irq_domain_free_hierarchy(struct irq_data *irq_data)
1171 {
1172 	struct irq_data *tmp;
1173 
1174 	while (irq_data) {
1175 		tmp = irq_data;
1176 		irq_data = irq_data->parent_data;
1177 		kfree(tmp);
1178 	}
1179 }
1180 
1181 static void irq_domain_free_irq_data(unsigned int virq, unsigned int nr_irqs)
1182 {
1183 	struct irq_data *irq_data, *tmp;
1184 	int i;
1185 
1186 	for (i = 0; i < nr_irqs; i++) {
1187 		irq_data = irq_get_irq_data(virq + i);
1188 		tmp = irq_data->parent_data;
1189 		irq_data->parent_data = NULL;
1190 		irq_data->domain = NULL;
1191 
1192 		__irq_domain_free_hierarchy(tmp);
1193 	}
1194 }
1195 
1196 /**
1197  * irq_domain_disconnect_hierarchy - Mark the first unused level of a hierarchy
1198  * @domain:	IRQ domain from which the hierarchy is to be disconnected
1199  * @virq:	IRQ number where the hierarchy is to be trimmed
1200  *
1201  * Marks the @virq level belonging to @domain as disconnected.
1202  * Returns -EINVAL if @virq doesn't have a valid irq_data pointing
1203  * to @domain.
1204  *
1205  * Its only use is to be able to trim levels of hierarchy that do not
1206  * have any real meaning for this interrupt, and that the driver marks
1207  * as such from its .alloc() callback.
1208  */
1209 int irq_domain_disconnect_hierarchy(struct irq_domain *domain,
1210 				    unsigned int virq)
1211 {
1212 	struct irq_data *irqd;
1213 
1214 	irqd = irq_domain_get_irq_data(domain, virq);
1215 	if (!irqd)
1216 		return -EINVAL;
1217 
1218 	irqd->chip = ERR_PTR(-ENOTCONN);
1219 	return 0;
1220 }
1221 EXPORT_SYMBOL_GPL(irq_domain_disconnect_hierarchy);
1222 
1223 static int irq_domain_trim_hierarchy(unsigned int virq)
1224 {
1225 	struct irq_data *tail, *irqd, *irq_data;
1226 
1227 	irq_data = irq_get_irq_data(virq);
1228 	tail = NULL;
1229 
1230 	/* The first entry must have a valid irqchip */
1231 	if (!irq_data->chip || IS_ERR(irq_data->chip))
1232 		return -EINVAL;
1233 
1234 	/*
1235 	 * Validate that the irq_data chain is sane in the presence of
1236 	 * a hierarchy trimming marker.
1237 	 */
1238 	for (irqd = irq_data->parent_data; irqd; irq_data = irqd, irqd = irqd->parent_data) {
1239 		/* Can't have a valid irqchip after a trim marker */
1240 		if (irqd->chip && tail)
1241 			return -EINVAL;
1242 
1243 		/* Can't have an empty irqchip before a trim marker */
1244 		if (!irqd->chip && !tail)
1245 			return -EINVAL;
1246 
1247 		if (IS_ERR(irqd->chip)) {
1248 			/* Only -ENOTCONN is a valid trim marker */
1249 			if (PTR_ERR(irqd->chip) != -ENOTCONN)
1250 				return -EINVAL;
1251 
1252 			tail = irq_data;
1253 		}
1254 	}
1255 
1256 	/* No trim marker, nothing to do */
1257 	if (!tail)
1258 		return 0;
1259 
1260 	pr_info("IRQ%d: trimming hierarchy from %s\n",
1261 		virq, tail->parent_data->domain->name);
1262 
1263 	/* Sever the inner part of the hierarchy...  */
1264 	irqd = tail;
1265 	tail = tail->parent_data;
1266 	irqd->parent_data = NULL;
1267 	__irq_domain_free_hierarchy(tail);
1268 
1269 	return 0;
1270 }
1271 
1272 static int irq_domain_alloc_irq_data(struct irq_domain *domain,
1273 				     unsigned int virq, unsigned int nr_irqs)
1274 {
1275 	struct irq_data *irq_data;
1276 	struct irq_domain *parent;
1277 	int i;
1278 
1279 	/* The outermost irq_data is embedded in struct irq_desc */
1280 	for (i = 0; i < nr_irqs; i++) {
1281 		irq_data = irq_get_irq_data(virq + i);
1282 		irq_data->domain = domain;
1283 
1284 		for (parent = domain->parent; parent; parent = parent->parent) {
1285 			irq_data = irq_domain_insert_irq_data(parent, irq_data);
1286 			if (!irq_data) {
1287 				irq_domain_free_irq_data(virq, i + 1);
1288 				return -ENOMEM;
1289 			}
1290 		}
1291 	}
1292 
1293 	return 0;
1294 }
1295 
1296 /**
1297  * irq_domain_get_irq_data - Get irq_data associated with @virq and @domain
1298  * @domain:	domain to match
1299  * @virq:	IRQ number to get irq_data
1300  */
1301 struct irq_data *irq_domain_get_irq_data(struct irq_domain *domain,
1302 					 unsigned int virq)
1303 {
1304 	struct irq_data *irq_data;
1305 
1306 	for (irq_data = irq_get_irq_data(virq); irq_data;
1307 	     irq_data = irq_data->parent_data)
1308 		if (irq_data->domain == domain)
1309 			return irq_data;
1310 
1311 	return NULL;
1312 }
1313 EXPORT_SYMBOL_GPL(irq_domain_get_irq_data);
1314 
1315 /**
1316  * irq_domain_set_hwirq_and_chip - Set hwirq and irqchip of @virq at @domain
1317  * @domain:	Interrupt domain to match
1318  * @virq:	IRQ number
1319  * @hwirq:	The hwirq number
1320  * @chip:	The associated interrupt chip
1321  * @chip_data:	The associated chip data
1322  */
1323 int irq_domain_set_hwirq_and_chip(struct irq_domain *domain, unsigned int virq,
1324 				  irq_hw_number_t hwirq,
1325 				  const struct irq_chip *chip,
1326 				  void *chip_data)
1327 {
1328 	struct irq_data *irq_data = irq_domain_get_irq_data(domain, virq);
1329 
1330 	if (!irq_data)
1331 		return -ENOENT;
1332 
1333 	irq_data->hwirq = hwirq;
1334 	irq_data->chip = (struct irq_chip *)(chip ? chip : &no_irq_chip);
1335 	irq_data->chip_data = chip_data;
1336 
1337 	return 0;
1338 }
1339 EXPORT_SYMBOL_GPL(irq_domain_set_hwirq_and_chip);
1340 
1341 /**
1342  * irq_domain_set_info - Set the complete data for a @virq in @domain
1343  * @domain:		Interrupt domain to match
1344  * @virq:		IRQ number
1345  * @hwirq:		The hardware interrupt number
1346  * @chip:		The associated interrupt chip
1347  * @chip_data:		The associated interrupt chip data
1348  * @handler:		The interrupt flow handler
1349  * @handler_data:	The interrupt flow handler data
1350  * @handler_name:	The interrupt handler name
1351  */
1352 void irq_domain_set_info(struct irq_domain *domain, unsigned int virq,
1353 			 irq_hw_number_t hwirq, const struct irq_chip *chip,
1354 			 void *chip_data, irq_flow_handler_t handler,
1355 			 void *handler_data, const char *handler_name)
1356 {
1357 	irq_domain_set_hwirq_and_chip(domain, virq, hwirq, chip, chip_data);
1358 	__irq_set_handler(virq, handler, 0, handler_name);
1359 	irq_set_handler_data(virq, handler_data);
1360 }
1361 EXPORT_SYMBOL(irq_domain_set_info);
1362 
1363 /**
1364  * irq_domain_free_irqs_common - Clear irq_data and free the parent
1365  * @domain:	Interrupt domain to match
1366  * @virq:	IRQ number to start with
1367  * @nr_irqs:	The number of irqs to free
1368  */
1369 void irq_domain_free_irqs_common(struct irq_domain *domain, unsigned int virq,
1370 				 unsigned int nr_irqs)
1371 {
1372 	struct irq_data *irq_data;
1373 	int i;
1374 
1375 	for (i = 0; i < nr_irqs; i++) {
1376 		irq_data = irq_domain_get_irq_data(domain, virq + i);
1377 		if (irq_data)
1378 			irq_domain_reset_irq_data(irq_data);
1379 	}
1380 	irq_domain_free_irqs_parent(domain, virq, nr_irqs);
1381 }
1382 EXPORT_SYMBOL_GPL(irq_domain_free_irqs_common);
1383 
1384 /**
1385  * irq_domain_free_irqs_top - Clear handler and handler data, clear irqdata and free parent
1386  * @domain:	Interrupt domain to match
1387  * @virq:	IRQ number to start with
1388  * @nr_irqs:	The number of irqs to free
1389  */
1390 void irq_domain_free_irqs_top(struct irq_domain *domain, unsigned int virq,
1391 			      unsigned int nr_irqs)
1392 {
1393 	int i;
1394 
1395 	for (i = 0; i < nr_irqs; i++) {
1396 		irq_set_handler_data(virq + i, NULL);
1397 		irq_set_handler(virq + i, NULL);
1398 	}
1399 	irq_domain_free_irqs_common(domain, virq, nr_irqs);
1400 }
1401 
1402 static void irq_domain_free_irqs_hierarchy(struct irq_domain *domain,
1403 					   unsigned int irq_base,
1404 					   unsigned int nr_irqs)
1405 {
1406 	unsigned int i;
1407 
1408 	if (!domain->ops->free)
1409 		return;
1410 
1411 	for (i = 0; i < nr_irqs; i++) {
1412 		if (irq_domain_get_irq_data(domain, irq_base + i))
1413 			domain->ops->free(domain, irq_base + i, 1);
1414 	}
1415 }
1416 
1417 int irq_domain_alloc_irqs_hierarchy(struct irq_domain *domain,
1418 				    unsigned int irq_base,
1419 				    unsigned int nr_irqs, void *arg)
1420 {
1421 	if (!domain->ops->alloc) {
1422 		pr_debug("domain->ops->alloc() is NULL\n");
1423 		return -ENOSYS;
1424 	}
1425 
1426 	return domain->ops->alloc(domain, irq_base, nr_irqs, arg);
1427 }
1428 
1429 /**
1430  * __irq_domain_alloc_irqs - Allocate IRQs from domain
1431  * @domain:	domain to allocate from
1432  * @irq_base:	allocate specified IRQ number if irq_base >= 0
1433  * @nr_irqs:	number of IRQs to allocate
1434  * @node:	NUMA node id for memory allocation
1435  * @arg:	domain specific argument
1436  * @realloc:	IRQ descriptors have already been allocated if true
1437  * @affinity:	Optional irq affinity mask for multiqueue devices
1438  *
1439  * Allocate IRQ numbers and initialized all data structures to support
1440  * hierarchy IRQ domains.
1441  * Parameter @realloc is mainly to support legacy IRQs.
1442  * Returns error code or allocated IRQ number
1443  *
1444  * The whole process to setup an IRQ has been split into two steps.
1445  * The first step, __irq_domain_alloc_irqs(), is to allocate IRQ
1446  * descriptor and required hardware resources. The second step,
1447  * irq_domain_activate_irq(), is to program the hardware with preallocated
1448  * resources. In this way, it's easier to rollback when failing to
1449  * allocate resources.
1450  */
1451 int __irq_domain_alloc_irqs(struct irq_domain *domain, int irq_base,
1452 			    unsigned int nr_irqs, int node, void *arg,
1453 			    bool realloc, const struct irq_affinity_desc *affinity)
1454 {
1455 	int i, ret, virq;
1456 
1457 	if (domain == NULL) {
1458 		domain = irq_default_domain;
1459 		if (WARN(!domain, "domain is NULL; cannot allocate IRQ\n"))
1460 			return -EINVAL;
1461 	}
1462 
1463 	if (realloc && irq_base >= 0) {
1464 		virq = irq_base;
1465 	} else {
1466 		virq = irq_domain_alloc_descs(irq_base, nr_irqs, 0, node,
1467 					      affinity);
1468 		if (virq < 0) {
1469 			pr_debug("cannot allocate IRQ(base %d, count %d)\n",
1470 				 irq_base, nr_irqs);
1471 			return virq;
1472 		}
1473 	}
1474 
1475 	if (irq_domain_alloc_irq_data(domain, virq, nr_irqs)) {
1476 		pr_debug("cannot allocate memory for IRQ%d\n", virq);
1477 		ret = -ENOMEM;
1478 		goto out_free_desc;
1479 	}
1480 
1481 	mutex_lock(&irq_domain_mutex);
1482 	ret = irq_domain_alloc_irqs_hierarchy(domain, virq, nr_irqs, arg);
1483 	if (ret < 0) {
1484 		mutex_unlock(&irq_domain_mutex);
1485 		goto out_free_irq_data;
1486 	}
1487 
1488 	for (i = 0; i < nr_irqs; i++) {
1489 		ret = irq_domain_trim_hierarchy(virq + i);
1490 		if (ret) {
1491 			mutex_unlock(&irq_domain_mutex);
1492 			goto out_free_irq_data;
1493 		}
1494 	}
1495 
1496 	for (i = 0; i < nr_irqs; i++)
1497 		irq_domain_insert_irq(virq + i);
1498 	mutex_unlock(&irq_domain_mutex);
1499 
1500 	return virq;
1501 
1502 out_free_irq_data:
1503 	irq_domain_free_irq_data(virq, nr_irqs);
1504 out_free_desc:
1505 	irq_free_descs(virq, nr_irqs);
1506 	return ret;
1507 }
1508 EXPORT_SYMBOL_GPL(__irq_domain_alloc_irqs);
1509 
1510 /* The irq_data was moved, fix the revmap to refer to the new location */
1511 static void irq_domain_fix_revmap(struct irq_data *d)
1512 {
1513 	void __rcu **slot;
1514 
1515 	if (irq_domain_is_nomap(d->domain))
1516 		return;
1517 
1518 	/* Fix up the revmap. */
1519 	mutex_lock(&d->domain->revmap_mutex);
1520 	if (d->hwirq < d->domain->revmap_size) {
1521 		/* Not using radix tree */
1522 		rcu_assign_pointer(d->domain->revmap[d->hwirq], d);
1523 	} else {
1524 		slot = radix_tree_lookup_slot(&d->domain->revmap_tree, d->hwirq);
1525 		if (slot)
1526 			radix_tree_replace_slot(&d->domain->revmap_tree, slot, d);
1527 	}
1528 	mutex_unlock(&d->domain->revmap_mutex);
1529 }
1530 
1531 /**
1532  * irq_domain_push_irq() - Push a domain in to the top of a hierarchy.
1533  * @domain:	Domain to push.
1534  * @virq:	Irq to push the domain in to.
1535  * @arg:	Passed to the irq_domain_ops alloc() function.
1536  *
1537  * For an already existing irqdomain hierarchy, as might be obtained
1538  * via a call to pci_enable_msix(), add an additional domain to the
1539  * head of the processing chain.  Must be called before request_irq()
1540  * has been called.
1541  */
1542 int irq_domain_push_irq(struct irq_domain *domain, int virq, void *arg)
1543 {
1544 	struct irq_data *child_irq_data;
1545 	struct irq_data *root_irq_data = irq_get_irq_data(virq);
1546 	struct irq_desc *desc;
1547 	int rv = 0;
1548 
1549 	/*
1550 	 * Check that no action has been set, which indicates the virq
1551 	 * is in a state where this function doesn't have to deal with
1552 	 * races between interrupt handling and maintaining the
1553 	 * hierarchy.  This will catch gross misuse.  Attempting to
1554 	 * make the check race free would require holding locks across
1555 	 * calls to struct irq_domain_ops->alloc(), which could lead
1556 	 * to deadlock, so we just do a simple check before starting.
1557 	 */
1558 	desc = irq_to_desc(virq);
1559 	if (!desc)
1560 		return -EINVAL;
1561 	if (WARN_ON(desc->action))
1562 		return -EBUSY;
1563 
1564 	if (domain == NULL)
1565 		return -EINVAL;
1566 
1567 	if (WARN_ON(!irq_domain_is_hierarchy(domain)))
1568 		return -EINVAL;
1569 
1570 	if (!root_irq_data)
1571 		return -EINVAL;
1572 
1573 	if (domain->parent != root_irq_data->domain)
1574 		return -EINVAL;
1575 
1576 	child_irq_data = kzalloc_node(sizeof(*child_irq_data), GFP_KERNEL,
1577 				      irq_data_get_node(root_irq_data));
1578 	if (!child_irq_data)
1579 		return -ENOMEM;
1580 
1581 	mutex_lock(&irq_domain_mutex);
1582 
1583 	/* Copy the original irq_data. */
1584 	*child_irq_data = *root_irq_data;
1585 
1586 	/*
1587 	 * Overwrite the root_irq_data, which is embedded in struct
1588 	 * irq_desc, with values for this domain.
1589 	 */
1590 	root_irq_data->parent_data = child_irq_data;
1591 	root_irq_data->domain = domain;
1592 	root_irq_data->mask = 0;
1593 	root_irq_data->hwirq = 0;
1594 	root_irq_data->chip = NULL;
1595 	root_irq_data->chip_data = NULL;
1596 
1597 	/* May (probably does) set hwirq, chip, etc. */
1598 	rv = irq_domain_alloc_irqs_hierarchy(domain, virq, 1, arg);
1599 	if (rv) {
1600 		/* Restore the original irq_data. */
1601 		*root_irq_data = *child_irq_data;
1602 		kfree(child_irq_data);
1603 		goto error;
1604 	}
1605 
1606 	irq_domain_fix_revmap(child_irq_data);
1607 	irq_domain_set_mapping(domain, root_irq_data->hwirq, root_irq_data);
1608 
1609 error:
1610 	mutex_unlock(&irq_domain_mutex);
1611 
1612 	return rv;
1613 }
1614 EXPORT_SYMBOL_GPL(irq_domain_push_irq);
1615 
1616 /**
1617  * irq_domain_pop_irq() - Remove a domain from the top of a hierarchy.
1618  * @domain:	Domain to remove.
1619  * @virq:	Irq to remove the domain from.
1620  *
1621  * Undo the effects of a call to irq_domain_push_irq().  Must be
1622  * called either before request_irq() or after free_irq().
1623  */
1624 int irq_domain_pop_irq(struct irq_domain *domain, int virq)
1625 {
1626 	struct irq_data *root_irq_data = irq_get_irq_data(virq);
1627 	struct irq_data *child_irq_data;
1628 	struct irq_data *tmp_irq_data;
1629 	struct irq_desc *desc;
1630 
1631 	/*
1632 	 * Check that no action is set, which indicates the virq is in
1633 	 * a state where this function doesn't have to deal with races
1634 	 * between interrupt handling and maintaining the hierarchy.
1635 	 * This will catch gross misuse.  Attempting to make the check
1636 	 * race free would require holding locks across calls to
1637 	 * struct irq_domain_ops->free(), which could lead to
1638 	 * deadlock, so we just do a simple check before starting.
1639 	 */
1640 	desc = irq_to_desc(virq);
1641 	if (!desc)
1642 		return -EINVAL;
1643 	if (WARN_ON(desc->action))
1644 		return -EBUSY;
1645 
1646 	if (domain == NULL)
1647 		return -EINVAL;
1648 
1649 	if (!root_irq_data)
1650 		return -EINVAL;
1651 
1652 	tmp_irq_data = irq_domain_get_irq_data(domain, virq);
1653 
1654 	/* We can only "pop" if this domain is at the top of the list */
1655 	if (WARN_ON(root_irq_data != tmp_irq_data))
1656 		return -EINVAL;
1657 
1658 	if (WARN_ON(root_irq_data->domain != domain))
1659 		return -EINVAL;
1660 
1661 	child_irq_data = root_irq_data->parent_data;
1662 	if (WARN_ON(!child_irq_data))
1663 		return -EINVAL;
1664 
1665 	mutex_lock(&irq_domain_mutex);
1666 
1667 	root_irq_data->parent_data = NULL;
1668 
1669 	irq_domain_clear_mapping(domain, root_irq_data->hwirq);
1670 	irq_domain_free_irqs_hierarchy(domain, virq, 1);
1671 
1672 	/* Restore the original irq_data. */
1673 	*root_irq_data = *child_irq_data;
1674 
1675 	irq_domain_fix_revmap(root_irq_data);
1676 
1677 	mutex_unlock(&irq_domain_mutex);
1678 
1679 	kfree(child_irq_data);
1680 
1681 	return 0;
1682 }
1683 EXPORT_SYMBOL_GPL(irq_domain_pop_irq);
1684 
1685 /**
1686  * irq_domain_free_irqs - Free IRQ number and associated data structures
1687  * @virq:	base IRQ number
1688  * @nr_irqs:	number of IRQs to free
1689  */
1690 void irq_domain_free_irqs(unsigned int virq, unsigned int nr_irqs)
1691 {
1692 	struct irq_data *data = irq_get_irq_data(virq);
1693 	int i;
1694 
1695 	if (WARN(!data || !data->domain || !data->domain->ops->free,
1696 		 "NULL pointer, cannot free irq\n"))
1697 		return;
1698 
1699 	mutex_lock(&irq_domain_mutex);
1700 	for (i = 0; i < nr_irqs; i++)
1701 		irq_domain_remove_irq(virq + i);
1702 	irq_domain_free_irqs_hierarchy(data->domain, virq, nr_irqs);
1703 	mutex_unlock(&irq_domain_mutex);
1704 
1705 	irq_domain_free_irq_data(virq, nr_irqs);
1706 	irq_free_descs(virq, nr_irqs);
1707 }
1708 
1709 /**
1710  * irq_domain_alloc_irqs_parent - Allocate interrupts from parent domain
1711  * @domain:	Domain below which interrupts must be allocated
1712  * @irq_base:	Base IRQ number
1713  * @nr_irqs:	Number of IRQs to allocate
1714  * @arg:	Allocation data (arch/domain specific)
1715  */
1716 int irq_domain_alloc_irqs_parent(struct irq_domain *domain,
1717 				 unsigned int irq_base, unsigned int nr_irqs,
1718 				 void *arg)
1719 {
1720 	if (!domain->parent)
1721 		return -ENOSYS;
1722 
1723 	return irq_domain_alloc_irqs_hierarchy(domain->parent, irq_base,
1724 					       nr_irqs, arg);
1725 }
1726 EXPORT_SYMBOL_GPL(irq_domain_alloc_irqs_parent);
1727 
1728 /**
1729  * irq_domain_free_irqs_parent - Free interrupts from parent domain
1730  * @domain:	Domain below which interrupts must be freed
1731  * @irq_base:	Base IRQ number
1732  * @nr_irqs:	Number of IRQs to free
1733  */
1734 void irq_domain_free_irqs_parent(struct irq_domain *domain,
1735 				 unsigned int irq_base, unsigned int nr_irqs)
1736 {
1737 	if (!domain->parent)
1738 		return;
1739 
1740 	irq_domain_free_irqs_hierarchy(domain->parent, irq_base, nr_irqs);
1741 }
1742 EXPORT_SYMBOL_GPL(irq_domain_free_irqs_parent);
1743 
1744 static void __irq_domain_deactivate_irq(struct irq_data *irq_data)
1745 {
1746 	if (irq_data && irq_data->domain) {
1747 		struct irq_domain *domain = irq_data->domain;
1748 
1749 		if (domain->ops->deactivate)
1750 			domain->ops->deactivate(domain, irq_data);
1751 		if (irq_data->parent_data)
1752 			__irq_domain_deactivate_irq(irq_data->parent_data);
1753 	}
1754 }
1755 
1756 static int __irq_domain_activate_irq(struct irq_data *irqd, bool reserve)
1757 {
1758 	int ret = 0;
1759 
1760 	if (irqd && irqd->domain) {
1761 		struct irq_domain *domain = irqd->domain;
1762 
1763 		if (irqd->parent_data)
1764 			ret = __irq_domain_activate_irq(irqd->parent_data,
1765 							reserve);
1766 		if (!ret && domain->ops->activate) {
1767 			ret = domain->ops->activate(domain, irqd, reserve);
1768 			/* Rollback in case of error */
1769 			if (ret && irqd->parent_data)
1770 				__irq_domain_deactivate_irq(irqd->parent_data);
1771 		}
1772 	}
1773 	return ret;
1774 }
1775 
1776 /**
1777  * irq_domain_activate_irq - Call domain_ops->activate recursively to activate
1778  *			     interrupt
1779  * @irq_data:	Outermost irq_data associated with interrupt
1780  * @reserve:	If set only reserve an interrupt vector instead of assigning one
1781  *
1782  * This is the second step to call domain_ops->activate to program interrupt
1783  * controllers, so the interrupt could actually get delivered.
1784  */
1785 int irq_domain_activate_irq(struct irq_data *irq_data, bool reserve)
1786 {
1787 	int ret = 0;
1788 
1789 	if (!irqd_is_activated(irq_data))
1790 		ret = __irq_domain_activate_irq(irq_data, reserve);
1791 	if (!ret)
1792 		irqd_set_activated(irq_data);
1793 	return ret;
1794 }
1795 
1796 /**
1797  * irq_domain_deactivate_irq - Call domain_ops->deactivate recursively to
1798  *			       deactivate interrupt
1799  * @irq_data: outermost irq_data associated with interrupt
1800  *
1801  * It calls domain_ops->deactivate to program interrupt controllers to disable
1802  * interrupt delivery.
1803  */
1804 void irq_domain_deactivate_irq(struct irq_data *irq_data)
1805 {
1806 	if (irqd_is_activated(irq_data)) {
1807 		__irq_domain_deactivate_irq(irq_data);
1808 		irqd_clr_activated(irq_data);
1809 	}
1810 }
1811 
1812 static void irq_domain_check_hierarchy(struct irq_domain *domain)
1813 {
1814 	/* Hierarchy irq_domains must implement callback alloc() */
1815 	if (domain->ops->alloc)
1816 		domain->flags |= IRQ_DOMAIN_FLAG_HIERARCHY;
1817 }
1818 
1819 /**
1820  * irq_domain_hierarchical_is_msi_remap - Check if the domain or any
1821  * parent has MSI remapping support
1822  * @domain: domain pointer
1823  */
1824 bool irq_domain_hierarchical_is_msi_remap(struct irq_domain *domain)
1825 {
1826 	for (; domain; domain = domain->parent) {
1827 		if (irq_domain_is_msi_remap(domain))
1828 			return true;
1829 	}
1830 	return false;
1831 }
1832 #else	/* CONFIG_IRQ_DOMAIN_HIERARCHY */
1833 /**
1834  * irq_domain_get_irq_data - Get irq_data associated with @virq and @domain
1835  * @domain:	domain to match
1836  * @virq:	IRQ number to get irq_data
1837  */
1838 struct irq_data *irq_domain_get_irq_data(struct irq_domain *domain,
1839 					 unsigned int virq)
1840 {
1841 	struct irq_data *irq_data = irq_get_irq_data(virq);
1842 
1843 	return (irq_data && irq_data->domain == domain) ? irq_data : NULL;
1844 }
1845 EXPORT_SYMBOL_GPL(irq_domain_get_irq_data);
1846 
1847 /**
1848  * irq_domain_set_info - Set the complete data for a @virq in @domain
1849  * @domain:		Interrupt domain to match
1850  * @virq:		IRQ number
1851  * @hwirq:		The hardware interrupt number
1852  * @chip:		The associated interrupt chip
1853  * @chip_data:		The associated interrupt chip data
1854  * @handler:		The interrupt flow handler
1855  * @handler_data:	The interrupt flow handler data
1856  * @handler_name:	The interrupt handler name
1857  */
1858 void irq_domain_set_info(struct irq_domain *domain, unsigned int virq,
1859 			 irq_hw_number_t hwirq, const struct irq_chip *chip,
1860 			 void *chip_data, irq_flow_handler_t handler,
1861 			 void *handler_data, const char *handler_name)
1862 {
1863 	irq_set_chip_and_handler_name(virq, chip, handler, handler_name);
1864 	irq_set_chip_data(virq, chip_data);
1865 	irq_set_handler_data(virq, handler_data);
1866 }
1867 
1868 static void irq_domain_check_hierarchy(struct irq_domain *domain)
1869 {
1870 }
1871 #endif	/* CONFIG_IRQ_DOMAIN_HIERARCHY */
1872 
1873 #ifdef CONFIG_GENERIC_IRQ_DEBUGFS
1874 static struct dentry *domain_dir;
1875 
1876 static void
1877 irq_domain_debug_show_one(struct seq_file *m, struct irq_domain *d, int ind)
1878 {
1879 	seq_printf(m, "%*sname:   %s\n", ind, "", d->name);
1880 	seq_printf(m, "%*ssize:   %u\n", ind + 1, "", d->revmap_size);
1881 	seq_printf(m, "%*smapped: %u\n", ind + 1, "", d->mapcount);
1882 	seq_printf(m, "%*sflags:  0x%08x\n", ind +1 , "", d->flags);
1883 	if (d->ops && d->ops->debug_show)
1884 		d->ops->debug_show(m, d, NULL, ind + 1);
1885 #ifdef	CONFIG_IRQ_DOMAIN_HIERARCHY
1886 	if (!d->parent)
1887 		return;
1888 	seq_printf(m, "%*sparent: %s\n", ind + 1, "", d->parent->name);
1889 	irq_domain_debug_show_one(m, d->parent, ind + 4);
1890 #endif
1891 }
1892 
1893 static int irq_domain_debug_show(struct seq_file *m, void *p)
1894 {
1895 	struct irq_domain *d = m->private;
1896 
1897 	/* Default domain? Might be NULL */
1898 	if (!d) {
1899 		if (!irq_default_domain)
1900 			return 0;
1901 		d = irq_default_domain;
1902 	}
1903 	irq_domain_debug_show_one(m, d, 0);
1904 	return 0;
1905 }
1906 DEFINE_SHOW_ATTRIBUTE(irq_domain_debug);
1907 
1908 static void debugfs_add_domain_dir(struct irq_domain *d)
1909 {
1910 	if (!d->name || !domain_dir)
1911 		return;
1912 	debugfs_create_file(d->name, 0444, domain_dir, d,
1913 			    &irq_domain_debug_fops);
1914 }
1915 
1916 static void debugfs_remove_domain_dir(struct irq_domain *d)
1917 {
1918 	debugfs_remove(debugfs_lookup(d->name, domain_dir));
1919 }
1920 
1921 void __init irq_domain_debugfs_init(struct dentry *root)
1922 {
1923 	struct irq_domain *d;
1924 
1925 	domain_dir = debugfs_create_dir("domains", root);
1926 
1927 	debugfs_create_file("default", 0444, domain_dir, NULL,
1928 			    &irq_domain_debug_fops);
1929 	mutex_lock(&irq_domain_mutex);
1930 	list_for_each_entry(d, &irq_domain_list, link)
1931 		debugfs_add_domain_dir(d);
1932 	mutex_unlock(&irq_domain_mutex);
1933 }
1934 #endif
1935