xref: /openbmc/linux/kernel/irq/irqdomain.c (revision 8bd1369b)
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 	void *data;
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 const struct fwnode_operations irqchip_fwnode_ops;
46 EXPORT_SYMBOL_GPL(irqchip_fwnode_ops);
47 
48 /**
49  * irq_domain_alloc_fwnode - Allocate a fwnode_handle suitable for
50  *                           identifying an irq domain
51  * @type:	Type of irqchip_fwnode. See linux/irqdomain.h
52  * @name:	Optional user provided domain name
53  * @id:		Optional user provided id if name != NULL
54  * @data:	Optional user-provided data
55  *
56  * Allocate a struct irqchip_fwid, and return a poiner to the embedded
57  * fwnode_handle (or NULL on failure).
58  *
59  * Note: The types IRQCHIP_FWNODE_NAMED and IRQCHIP_FWNODE_NAMED_ID are
60  * solely to transport name information to irqdomain creation code. The
61  * node is not stored. For other types the pointer is kept in the irq
62  * domain struct.
63  */
64 struct fwnode_handle *__irq_domain_alloc_fwnode(unsigned int type, int id,
65 						const char *name, void *data)
66 {
67 	struct irqchip_fwid *fwid;
68 	char *n;
69 
70 	fwid = kzalloc(sizeof(*fwid), GFP_KERNEL);
71 
72 	switch (type) {
73 	case IRQCHIP_FWNODE_NAMED:
74 		n = kasprintf(GFP_KERNEL, "%s", name);
75 		break;
76 	case IRQCHIP_FWNODE_NAMED_ID:
77 		n = kasprintf(GFP_KERNEL, "%s-%d", name, id);
78 		break;
79 	default:
80 		n = kasprintf(GFP_KERNEL, "irqchip@%p", data);
81 		break;
82 	}
83 
84 	if (!fwid || !n) {
85 		kfree(fwid);
86 		kfree(n);
87 		return NULL;
88 	}
89 
90 	fwid->type = type;
91 	fwid->name = n;
92 	fwid->data = data;
93 	fwid->fwnode.ops = &irqchip_fwnode_ops;
94 	return &fwid->fwnode;
95 }
96 EXPORT_SYMBOL_GPL(__irq_domain_alloc_fwnode);
97 
98 /**
99  * irq_domain_free_fwnode - Free a non-OF-backed fwnode_handle
100  *
101  * Free a fwnode_handle allocated with irq_domain_alloc_fwnode.
102  */
103 void irq_domain_free_fwnode(struct fwnode_handle *fwnode)
104 {
105 	struct irqchip_fwid *fwid;
106 
107 	if (WARN_ON(!is_fwnode_irqchip(fwnode)))
108 		return;
109 
110 	fwid = container_of(fwnode, struct irqchip_fwid, fwnode);
111 	kfree(fwid->name);
112 	kfree(fwid);
113 }
114 EXPORT_SYMBOL_GPL(irq_domain_free_fwnode);
115 
116 /**
117  * __irq_domain_add() - Allocate a new irq_domain data structure
118  * @fwnode: firmware node for the interrupt controller
119  * @size: Size of linear map; 0 for radix mapping only
120  * @hwirq_max: Maximum number of interrupts supported by controller
121  * @direct_max: Maximum value of direct maps; Use ~0 for no limit; 0 for no
122  *              direct mapping
123  * @ops: domain callbacks
124  * @host_data: Controller private data pointer
125  *
126  * Allocates and initialize and irq_domain structure.
127  * Returns pointer to IRQ domain, or NULL on failure.
128  */
129 struct irq_domain *__irq_domain_add(struct fwnode_handle *fwnode, int size,
130 				    irq_hw_number_t hwirq_max, int direct_max,
131 				    const struct irq_domain_ops *ops,
132 				    void *host_data)
133 {
134 	struct device_node *of_node = to_of_node(fwnode);
135 	struct irqchip_fwid *fwid;
136 	struct irq_domain *domain;
137 
138 	static atomic_t unknown_domains;
139 
140 	domain = kzalloc_node(sizeof(*domain) + (sizeof(unsigned int) * size),
141 			      GFP_KERNEL, of_node_to_nid(of_node));
142 	if (WARN_ON(!domain))
143 		return NULL;
144 
145 	if (fwnode && is_fwnode_irqchip(fwnode)) {
146 		fwid = container_of(fwnode, struct irqchip_fwid, fwnode);
147 
148 		switch (fwid->type) {
149 		case IRQCHIP_FWNODE_NAMED:
150 		case IRQCHIP_FWNODE_NAMED_ID:
151 			domain->name = kstrdup(fwid->name, GFP_KERNEL);
152 			if (!domain->name) {
153 				kfree(domain);
154 				return NULL;
155 			}
156 			domain->flags |= IRQ_DOMAIN_NAME_ALLOCATED;
157 			break;
158 		default:
159 			domain->fwnode = fwnode;
160 			domain->name = fwid->name;
161 			break;
162 		}
163 #ifdef CONFIG_ACPI
164 	} else if (is_acpi_device_node(fwnode)) {
165 		struct acpi_buffer buf = {
166 			.length = ACPI_ALLOCATE_BUFFER,
167 		};
168 		acpi_handle handle;
169 
170 		handle = acpi_device_handle(to_acpi_device_node(fwnode));
171 		if (acpi_get_name(handle, ACPI_FULL_PATHNAME, &buf) == AE_OK) {
172 			domain->name = buf.pointer;
173 			domain->flags |= IRQ_DOMAIN_NAME_ALLOCATED;
174 		}
175 
176 		domain->fwnode = fwnode;
177 #endif
178 	} else if (of_node) {
179 		char *name;
180 
181 		/*
182 		 * DT paths contain '/', which debugfs is legitimately
183 		 * unhappy about. Replace them with ':', which does
184 		 * the trick and is not as offensive as '\'...
185 		 */
186 		name = kstrdup(of_node_full_name(of_node), GFP_KERNEL);
187 		if (!name) {
188 			kfree(domain);
189 			return NULL;
190 		}
191 
192 		strreplace(name, '/', ':');
193 
194 		domain->name = name;
195 		domain->fwnode = fwnode;
196 		domain->flags |= IRQ_DOMAIN_NAME_ALLOCATED;
197 	}
198 
199 	if (!domain->name) {
200 		if (fwnode)
201 			pr_err("Invalid fwnode type for irqdomain\n");
202 		domain->name = kasprintf(GFP_KERNEL, "unknown-%d",
203 					 atomic_inc_return(&unknown_domains));
204 		if (!domain->name) {
205 			kfree(domain);
206 			return NULL;
207 		}
208 		domain->flags |= IRQ_DOMAIN_NAME_ALLOCATED;
209 	}
210 
211 	of_node_get(of_node);
212 
213 	/* Fill structure */
214 	INIT_RADIX_TREE(&domain->revmap_tree, GFP_KERNEL);
215 	mutex_init(&domain->revmap_tree_mutex);
216 	domain->ops = ops;
217 	domain->host_data = host_data;
218 	domain->hwirq_max = hwirq_max;
219 	domain->revmap_size = size;
220 	domain->revmap_direct_max_irq = direct_max;
221 	irq_domain_check_hierarchy(domain);
222 
223 	mutex_lock(&irq_domain_mutex);
224 	debugfs_add_domain_dir(domain);
225 	list_add(&domain->link, &irq_domain_list);
226 	mutex_unlock(&irq_domain_mutex);
227 
228 	pr_debug("Added domain %s\n", domain->name);
229 	return domain;
230 }
231 EXPORT_SYMBOL_GPL(__irq_domain_add);
232 
233 /**
234  * irq_domain_remove() - Remove an irq domain.
235  * @domain: domain to remove
236  *
237  * This routine is used to remove an irq domain. The caller must ensure
238  * that all mappings within the domain have been disposed of prior to
239  * use, depending on the revmap type.
240  */
241 void irq_domain_remove(struct irq_domain *domain)
242 {
243 	mutex_lock(&irq_domain_mutex);
244 	debugfs_remove_domain_dir(domain);
245 
246 	WARN_ON(!radix_tree_empty(&domain->revmap_tree));
247 
248 	list_del(&domain->link);
249 
250 	/*
251 	 * If the going away domain is the default one, reset it.
252 	 */
253 	if (unlikely(irq_default_domain == domain))
254 		irq_set_default_host(NULL);
255 
256 	mutex_unlock(&irq_domain_mutex);
257 
258 	pr_debug("Removed domain %s\n", domain->name);
259 
260 	of_node_put(irq_domain_get_of_node(domain));
261 	if (domain->flags & IRQ_DOMAIN_NAME_ALLOCATED)
262 		kfree(domain->name);
263 	kfree(domain);
264 }
265 EXPORT_SYMBOL_GPL(irq_domain_remove);
266 
267 void irq_domain_update_bus_token(struct irq_domain *domain,
268 				 enum irq_domain_bus_token bus_token)
269 {
270 	char *name;
271 
272 	if (domain->bus_token == bus_token)
273 		return;
274 
275 	mutex_lock(&irq_domain_mutex);
276 
277 	domain->bus_token = bus_token;
278 
279 	name = kasprintf(GFP_KERNEL, "%s-%d", domain->name, bus_token);
280 	if (!name) {
281 		mutex_unlock(&irq_domain_mutex);
282 		return;
283 	}
284 
285 	debugfs_remove_domain_dir(domain);
286 
287 	if (domain->flags & IRQ_DOMAIN_NAME_ALLOCATED)
288 		kfree(domain->name);
289 	else
290 		domain->flags |= IRQ_DOMAIN_NAME_ALLOCATED;
291 
292 	domain->name = name;
293 	debugfs_add_domain_dir(domain);
294 
295 	mutex_unlock(&irq_domain_mutex);
296 }
297 
298 /**
299  * irq_domain_add_simple() - Register an irq_domain and optionally map a range of irqs
300  * @of_node: pointer to interrupt controller's device tree node.
301  * @size: total number of irqs in mapping
302  * @first_irq: first number of irq block assigned to the domain,
303  *	pass zero to assign irqs on-the-fly. If first_irq is non-zero, then
304  *	pre-map all of the irqs in the domain to virqs starting at first_irq.
305  * @ops: domain callbacks
306  * @host_data: Controller private data pointer
307  *
308  * Allocates an irq_domain, and optionally if first_irq is positive then also
309  * allocate irq_descs and map all of the hwirqs to virqs starting at first_irq.
310  *
311  * This is intended to implement the expected behaviour for most
312  * interrupt controllers. If device tree is used, then first_irq will be 0 and
313  * irqs get mapped dynamically on the fly. However, if the controller requires
314  * static virq assignments (non-DT boot) then it will set that up correctly.
315  */
316 struct irq_domain *irq_domain_add_simple(struct device_node *of_node,
317 					 unsigned int size,
318 					 unsigned int first_irq,
319 					 const struct irq_domain_ops *ops,
320 					 void *host_data)
321 {
322 	struct irq_domain *domain;
323 
324 	domain = __irq_domain_add(of_node_to_fwnode(of_node), size, size, 0, ops, host_data);
325 	if (!domain)
326 		return NULL;
327 
328 	if (first_irq > 0) {
329 		if (IS_ENABLED(CONFIG_SPARSE_IRQ)) {
330 			/* attempt to allocated irq_descs */
331 			int rc = irq_alloc_descs(first_irq, first_irq, size,
332 						 of_node_to_nid(of_node));
333 			if (rc < 0)
334 				pr_info("Cannot allocate irq_descs @ IRQ%d, assuming pre-allocated\n",
335 					first_irq);
336 		}
337 		irq_domain_associate_many(domain, first_irq, 0, size);
338 	}
339 
340 	return domain;
341 }
342 EXPORT_SYMBOL_GPL(irq_domain_add_simple);
343 
344 /**
345  * irq_domain_add_legacy() - Allocate and register a legacy revmap irq_domain.
346  * @of_node: pointer to interrupt controller's device tree node.
347  * @size: total number of irqs in legacy mapping
348  * @first_irq: first number of irq block assigned to the domain
349  * @first_hwirq: first hwirq number to use for the translation. Should normally
350  *               be '0', but a positive integer can be used if the effective
351  *               hwirqs numbering does not begin at zero.
352  * @ops: map/unmap domain callbacks
353  * @host_data: Controller private data pointer
354  *
355  * Note: the map() callback will be called before this function returns
356  * for all legacy interrupts except 0 (which is always the invalid irq for
357  * a legacy controller).
358  */
359 struct irq_domain *irq_domain_add_legacy(struct device_node *of_node,
360 					 unsigned int size,
361 					 unsigned int first_irq,
362 					 irq_hw_number_t first_hwirq,
363 					 const struct irq_domain_ops *ops,
364 					 void *host_data)
365 {
366 	struct irq_domain *domain;
367 
368 	domain = __irq_domain_add(of_node_to_fwnode(of_node), first_hwirq + size,
369 				  first_hwirq + size, 0, ops, host_data);
370 	if (domain)
371 		irq_domain_associate_many(domain, first_irq, first_hwirq, size);
372 
373 	return domain;
374 }
375 EXPORT_SYMBOL_GPL(irq_domain_add_legacy);
376 
377 /**
378  * irq_find_matching_fwspec() - Locates a domain for a given fwspec
379  * @fwspec: FW specifier for an interrupt
380  * @bus_token: domain-specific data
381  */
382 struct irq_domain *irq_find_matching_fwspec(struct irq_fwspec *fwspec,
383 					    enum irq_domain_bus_token bus_token)
384 {
385 	struct irq_domain *h, *found = NULL;
386 	struct fwnode_handle *fwnode = fwspec->fwnode;
387 	int rc;
388 
389 	/* We might want to match the legacy controller last since
390 	 * it might potentially be set to match all interrupts in
391 	 * the absence of a device node. This isn't a problem so far
392 	 * yet though...
393 	 *
394 	 * bus_token == DOMAIN_BUS_ANY matches any domain, any other
395 	 * values must generate an exact match for the domain to be
396 	 * selected.
397 	 */
398 	mutex_lock(&irq_domain_mutex);
399 	list_for_each_entry(h, &irq_domain_list, link) {
400 		if (h->ops->select && fwspec->param_count)
401 			rc = h->ops->select(h, fwspec, bus_token);
402 		else if (h->ops->match)
403 			rc = h->ops->match(h, to_of_node(fwnode), bus_token);
404 		else
405 			rc = ((fwnode != NULL) && (h->fwnode == fwnode) &&
406 			      ((bus_token == DOMAIN_BUS_ANY) ||
407 			       (h->bus_token == bus_token)));
408 
409 		if (rc) {
410 			found = h;
411 			break;
412 		}
413 	}
414 	mutex_unlock(&irq_domain_mutex);
415 	return found;
416 }
417 EXPORT_SYMBOL_GPL(irq_find_matching_fwspec);
418 
419 /**
420  * irq_domain_check_msi_remap - Check whether all MSI irq domains implement
421  * IRQ remapping
422  *
423  * Return: false if any MSI irq domain does not support IRQ remapping,
424  * true otherwise (including if there is no MSI irq domain)
425  */
426 bool irq_domain_check_msi_remap(void)
427 {
428 	struct irq_domain *h;
429 	bool ret = true;
430 
431 	mutex_lock(&irq_domain_mutex);
432 	list_for_each_entry(h, &irq_domain_list, link) {
433 		if (irq_domain_is_msi(h) &&
434 		    !irq_domain_hierarchical_is_msi_remap(h)) {
435 			ret = false;
436 			break;
437 		}
438 	}
439 	mutex_unlock(&irq_domain_mutex);
440 	return ret;
441 }
442 EXPORT_SYMBOL_GPL(irq_domain_check_msi_remap);
443 
444 /**
445  * irq_set_default_host() - Set a "default" irq domain
446  * @domain: default domain pointer
447  *
448  * For convenience, it's possible to set a "default" domain that will be used
449  * whenever NULL is passed to irq_create_mapping(). It makes life easier for
450  * platforms that want to manipulate a few hard coded interrupt numbers that
451  * aren't properly represented in the device-tree.
452  */
453 void irq_set_default_host(struct irq_domain *domain)
454 {
455 	pr_debug("Default domain set to @0x%p\n", domain);
456 
457 	irq_default_domain = domain;
458 }
459 EXPORT_SYMBOL_GPL(irq_set_default_host);
460 
461 static void irq_domain_clear_mapping(struct irq_domain *domain,
462 				     irq_hw_number_t hwirq)
463 {
464 	if (hwirq < domain->revmap_size) {
465 		domain->linear_revmap[hwirq] = 0;
466 	} else {
467 		mutex_lock(&domain->revmap_tree_mutex);
468 		radix_tree_delete(&domain->revmap_tree, hwirq);
469 		mutex_unlock(&domain->revmap_tree_mutex);
470 	}
471 }
472 
473 static void irq_domain_set_mapping(struct irq_domain *domain,
474 				   irq_hw_number_t hwirq,
475 				   struct irq_data *irq_data)
476 {
477 	if (hwirq < domain->revmap_size) {
478 		domain->linear_revmap[hwirq] = irq_data->irq;
479 	} else {
480 		mutex_lock(&domain->revmap_tree_mutex);
481 		radix_tree_insert(&domain->revmap_tree, hwirq, irq_data);
482 		mutex_unlock(&domain->revmap_tree_mutex);
483 	}
484 }
485 
486 void irq_domain_disassociate(struct irq_domain *domain, unsigned int irq)
487 {
488 	struct irq_data *irq_data = irq_get_irq_data(irq);
489 	irq_hw_number_t hwirq;
490 
491 	if (WARN(!irq_data || irq_data->domain != domain,
492 		 "virq%i doesn't exist; cannot disassociate\n", irq))
493 		return;
494 
495 	hwirq = irq_data->hwirq;
496 	irq_set_status_flags(irq, IRQ_NOREQUEST);
497 
498 	/* remove chip and handler */
499 	irq_set_chip_and_handler(irq, NULL, NULL);
500 
501 	/* Make sure it's completed */
502 	synchronize_irq(irq);
503 
504 	/* Tell the PIC about it */
505 	if (domain->ops->unmap)
506 		domain->ops->unmap(domain, irq);
507 	smp_mb();
508 
509 	irq_data->domain = NULL;
510 	irq_data->hwirq = 0;
511 	domain->mapcount--;
512 
513 	/* Clear reverse map for this hwirq */
514 	irq_domain_clear_mapping(domain, hwirq);
515 }
516 
517 int irq_domain_associate(struct irq_domain *domain, unsigned int virq,
518 			 irq_hw_number_t hwirq)
519 {
520 	struct irq_data *irq_data = irq_get_irq_data(virq);
521 	int ret;
522 
523 	if (WARN(hwirq >= domain->hwirq_max,
524 		 "error: hwirq 0x%x is too large for %s\n", (int)hwirq, domain->name))
525 		return -EINVAL;
526 	if (WARN(!irq_data, "error: virq%i is not allocated", virq))
527 		return -EINVAL;
528 	if (WARN(irq_data->domain, "error: virq%i is already associated", virq))
529 		return -EINVAL;
530 
531 	mutex_lock(&irq_domain_mutex);
532 	irq_data->hwirq = hwirq;
533 	irq_data->domain = domain;
534 	if (domain->ops->map) {
535 		ret = domain->ops->map(domain, virq, hwirq);
536 		if (ret != 0) {
537 			/*
538 			 * If map() returns -EPERM, this interrupt is protected
539 			 * by the firmware or some other service and shall not
540 			 * be mapped. Don't bother telling the user about it.
541 			 */
542 			if (ret != -EPERM) {
543 				pr_info("%s didn't like hwirq-0x%lx to VIRQ%i mapping (rc=%d)\n",
544 				       domain->name, hwirq, virq, ret);
545 			}
546 			irq_data->domain = NULL;
547 			irq_data->hwirq = 0;
548 			mutex_unlock(&irq_domain_mutex);
549 			return ret;
550 		}
551 
552 		/* If not already assigned, give the domain the chip's name */
553 		if (!domain->name && irq_data->chip)
554 			domain->name = irq_data->chip->name;
555 	}
556 
557 	domain->mapcount++;
558 	irq_domain_set_mapping(domain, hwirq, irq_data);
559 	mutex_unlock(&irq_domain_mutex);
560 
561 	irq_clear_status_flags(virq, IRQ_NOREQUEST);
562 
563 	return 0;
564 }
565 EXPORT_SYMBOL_GPL(irq_domain_associate);
566 
567 void irq_domain_associate_many(struct irq_domain *domain, unsigned int irq_base,
568 			       irq_hw_number_t hwirq_base, int count)
569 {
570 	struct device_node *of_node;
571 	int i;
572 
573 	of_node = irq_domain_get_of_node(domain);
574 	pr_debug("%s(%s, irqbase=%i, hwbase=%i, count=%i)\n", __func__,
575 		of_node_full_name(of_node), irq_base, (int)hwirq_base, count);
576 
577 	for (i = 0; i < count; i++) {
578 		irq_domain_associate(domain, irq_base + i, hwirq_base + i);
579 	}
580 }
581 EXPORT_SYMBOL_GPL(irq_domain_associate_many);
582 
583 /**
584  * irq_create_direct_mapping() - Allocate an irq for direct mapping
585  * @domain: domain to allocate the irq for or NULL for default domain
586  *
587  * This routine is used for irq controllers which can choose the hardware
588  * interrupt numbers they generate. In such a case it's simplest to use
589  * the linux irq as the hardware interrupt number. It still uses the linear
590  * or radix tree to store the mapping, but the irq controller can optimize
591  * the revmap path by using the hwirq directly.
592  */
593 unsigned int irq_create_direct_mapping(struct irq_domain *domain)
594 {
595 	struct device_node *of_node;
596 	unsigned int virq;
597 
598 	if (domain == NULL)
599 		domain = irq_default_domain;
600 
601 	of_node = irq_domain_get_of_node(domain);
602 	virq = irq_alloc_desc_from(1, of_node_to_nid(of_node));
603 	if (!virq) {
604 		pr_debug("create_direct virq allocation failed\n");
605 		return 0;
606 	}
607 	if (virq >= domain->revmap_direct_max_irq) {
608 		pr_err("ERROR: no free irqs available below %i maximum\n",
609 			domain->revmap_direct_max_irq);
610 		irq_free_desc(virq);
611 		return 0;
612 	}
613 	pr_debug("create_direct obtained virq %d\n", virq);
614 
615 	if (irq_domain_associate(domain, virq, virq)) {
616 		irq_free_desc(virq);
617 		return 0;
618 	}
619 
620 	return virq;
621 }
622 EXPORT_SYMBOL_GPL(irq_create_direct_mapping);
623 
624 /**
625  * irq_create_mapping() - Map a hardware interrupt into linux irq space
626  * @domain: domain owning this hardware interrupt or NULL for default domain
627  * @hwirq: hardware irq number in that domain space
628  *
629  * Only one mapping per hardware interrupt is permitted. Returns a linux
630  * irq number.
631  * If the sense/trigger is to be specified, set_irq_type() should be called
632  * on the number returned from that call.
633  */
634 unsigned int irq_create_mapping(struct irq_domain *domain,
635 				irq_hw_number_t hwirq)
636 {
637 	struct device_node *of_node;
638 	int virq;
639 
640 	pr_debug("irq_create_mapping(0x%p, 0x%lx)\n", domain, hwirq);
641 
642 	/* Look for default domain if nececssary */
643 	if (domain == NULL)
644 		domain = irq_default_domain;
645 	if (domain == NULL) {
646 		WARN(1, "%s(, %lx) called with NULL domain\n", __func__, hwirq);
647 		return 0;
648 	}
649 	pr_debug("-> using domain @%p\n", domain);
650 
651 	of_node = irq_domain_get_of_node(domain);
652 
653 	/* Check if mapping already exists */
654 	virq = irq_find_mapping(domain, hwirq);
655 	if (virq) {
656 		pr_debug("-> existing mapping on virq %d\n", virq);
657 		return virq;
658 	}
659 
660 	/* Allocate a virtual interrupt number */
661 	virq = irq_domain_alloc_descs(-1, 1, hwirq, of_node_to_nid(of_node), NULL);
662 	if (virq <= 0) {
663 		pr_debug("-> virq allocation failed\n");
664 		return 0;
665 	}
666 
667 	if (irq_domain_associate(domain, virq, hwirq)) {
668 		irq_free_desc(virq);
669 		return 0;
670 	}
671 
672 	pr_debug("irq %lu on domain %s mapped to virtual irq %u\n",
673 		hwirq, of_node_full_name(of_node), virq);
674 
675 	return virq;
676 }
677 EXPORT_SYMBOL_GPL(irq_create_mapping);
678 
679 /**
680  * irq_create_strict_mappings() - Map a range of hw irqs to fixed linux irqs
681  * @domain: domain owning the interrupt range
682  * @irq_base: beginning of linux IRQ range
683  * @hwirq_base: beginning of hardware IRQ range
684  * @count: Number of interrupts to map
685  *
686  * This routine is used for allocating and mapping a range of hardware
687  * irqs to linux irqs where the linux irq numbers are at pre-defined
688  * locations. For use by controllers that already have static mappings
689  * to insert in to the domain.
690  *
691  * Non-linear users can use irq_create_identity_mapping() for IRQ-at-a-time
692  * domain insertion.
693  *
694  * 0 is returned upon success, while any failure to establish a static
695  * mapping is treated as an error.
696  */
697 int irq_create_strict_mappings(struct irq_domain *domain, unsigned int irq_base,
698 			       irq_hw_number_t hwirq_base, int count)
699 {
700 	struct device_node *of_node;
701 	int ret;
702 
703 	of_node = irq_domain_get_of_node(domain);
704 	ret = irq_alloc_descs(irq_base, irq_base, count,
705 			      of_node_to_nid(of_node));
706 	if (unlikely(ret < 0))
707 		return ret;
708 
709 	irq_domain_associate_many(domain, irq_base, hwirq_base, count);
710 	return 0;
711 }
712 EXPORT_SYMBOL_GPL(irq_create_strict_mappings);
713 
714 static int irq_domain_translate(struct irq_domain *d,
715 				struct irq_fwspec *fwspec,
716 				irq_hw_number_t *hwirq, unsigned int *type)
717 {
718 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
719 	if (d->ops->translate)
720 		return d->ops->translate(d, fwspec, hwirq, type);
721 #endif
722 	if (d->ops->xlate)
723 		return d->ops->xlate(d, to_of_node(fwspec->fwnode),
724 				     fwspec->param, fwspec->param_count,
725 				     hwirq, type);
726 
727 	/* If domain has no translation, then we assume interrupt line */
728 	*hwirq = fwspec->param[0];
729 	return 0;
730 }
731 
732 static void of_phandle_args_to_fwspec(struct of_phandle_args *irq_data,
733 				      struct irq_fwspec *fwspec)
734 {
735 	int i;
736 
737 	fwspec->fwnode = irq_data->np ? &irq_data->np->fwnode : NULL;
738 	fwspec->param_count = irq_data->args_count;
739 
740 	for (i = 0; i < irq_data->args_count; i++)
741 		fwspec->param[i] = irq_data->args[i];
742 }
743 
744 unsigned int irq_create_fwspec_mapping(struct irq_fwspec *fwspec)
745 {
746 	struct irq_domain *domain;
747 	struct irq_data *irq_data;
748 	irq_hw_number_t hwirq;
749 	unsigned int type = IRQ_TYPE_NONE;
750 	int virq;
751 
752 	if (fwspec->fwnode) {
753 		domain = irq_find_matching_fwspec(fwspec, DOMAIN_BUS_WIRED);
754 		if (!domain)
755 			domain = irq_find_matching_fwspec(fwspec, DOMAIN_BUS_ANY);
756 	} else {
757 		domain = irq_default_domain;
758 	}
759 
760 	if (!domain) {
761 		pr_warn("no irq domain found for %s !\n",
762 			of_node_full_name(to_of_node(fwspec->fwnode)));
763 		return 0;
764 	}
765 
766 	if (irq_domain_translate(domain, fwspec, &hwirq, &type))
767 		return 0;
768 
769 	/*
770 	 * WARN if the irqchip returns a type with bits
771 	 * outside the sense mask set and clear these bits.
772 	 */
773 	if (WARN_ON(type & ~IRQ_TYPE_SENSE_MASK))
774 		type &= IRQ_TYPE_SENSE_MASK;
775 
776 	/*
777 	 * If we've already configured this interrupt,
778 	 * don't do it again, or hell will break loose.
779 	 */
780 	virq = irq_find_mapping(domain, hwirq);
781 	if (virq) {
782 		/*
783 		 * If the trigger type is not specified or matches the
784 		 * current trigger type then we are done so return the
785 		 * interrupt number.
786 		 */
787 		if (type == IRQ_TYPE_NONE || type == irq_get_trigger_type(virq))
788 			return virq;
789 
790 		/*
791 		 * If the trigger type has not been set yet, then set
792 		 * it now and return the interrupt number.
793 		 */
794 		if (irq_get_trigger_type(virq) == IRQ_TYPE_NONE) {
795 			irq_data = irq_get_irq_data(virq);
796 			if (!irq_data)
797 				return 0;
798 
799 			irqd_set_trigger_type(irq_data, type);
800 			return virq;
801 		}
802 
803 		pr_warn("type mismatch, failed to map hwirq-%lu for %s!\n",
804 			hwirq, of_node_full_name(to_of_node(fwspec->fwnode)));
805 		return 0;
806 	}
807 
808 	if (irq_domain_is_hierarchy(domain)) {
809 		virq = irq_domain_alloc_irqs(domain, 1, NUMA_NO_NODE, fwspec);
810 		if (virq <= 0)
811 			return 0;
812 	} else {
813 		/* Create mapping */
814 		virq = irq_create_mapping(domain, hwirq);
815 		if (!virq)
816 			return virq;
817 	}
818 
819 	irq_data = irq_get_irq_data(virq);
820 	if (!irq_data) {
821 		if (irq_domain_is_hierarchy(domain))
822 			irq_domain_free_irqs(virq, 1);
823 		else
824 			irq_dispose_mapping(virq);
825 		return 0;
826 	}
827 
828 	/* Store trigger type */
829 	irqd_set_trigger_type(irq_data, type);
830 
831 	return virq;
832 }
833 EXPORT_SYMBOL_GPL(irq_create_fwspec_mapping);
834 
835 unsigned int irq_create_of_mapping(struct of_phandle_args *irq_data)
836 {
837 	struct irq_fwspec fwspec;
838 
839 	of_phandle_args_to_fwspec(irq_data, &fwspec);
840 	return irq_create_fwspec_mapping(&fwspec);
841 }
842 EXPORT_SYMBOL_GPL(irq_create_of_mapping);
843 
844 /**
845  * irq_dispose_mapping() - Unmap an interrupt
846  * @virq: linux irq number of the interrupt to unmap
847  */
848 void irq_dispose_mapping(unsigned int virq)
849 {
850 	struct irq_data *irq_data = irq_get_irq_data(virq);
851 	struct irq_domain *domain;
852 
853 	if (!virq || !irq_data)
854 		return;
855 
856 	domain = irq_data->domain;
857 	if (WARN_ON(domain == NULL))
858 		return;
859 
860 	if (irq_domain_is_hierarchy(domain)) {
861 		irq_domain_free_irqs(virq, 1);
862 	} else {
863 		irq_domain_disassociate(domain, virq);
864 		irq_free_desc(virq);
865 	}
866 }
867 EXPORT_SYMBOL_GPL(irq_dispose_mapping);
868 
869 /**
870  * irq_find_mapping() - Find a linux irq from an hw irq number.
871  * @domain: domain owning this hardware interrupt
872  * @hwirq: hardware irq number in that domain space
873  */
874 unsigned int irq_find_mapping(struct irq_domain *domain,
875 			      irq_hw_number_t hwirq)
876 {
877 	struct irq_data *data;
878 
879 	/* Look for default domain if nececssary */
880 	if (domain == NULL)
881 		domain = irq_default_domain;
882 	if (domain == NULL)
883 		return 0;
884 
885 	if (hwirq < domain->revmap_direct_max_irq) {
886 		data = irq_domain_get_irq_data(domain, hwirq);
887 		if (data && data->hwirq == hwirq)
888 			return hwirq;
889 	}
890 
891 	/* Check if the hwirq is in the linear revmap. */
892 	if (hwirq < domain->revmap_size)
893 		return domain->linear_revmap[hwirq];
894 
895 	rcu_read_lock();
896 	data = radix_tree_lookup(&domain->revmap_tree, hwirq);
897 	rcu_read_unlock();
898 	return data ? data->irq : 0;
899 }
900 EXPORT_SYMBOL_GPL(irq_find_mapping);
901 
902 /**
903  * irq_domain_xlate_onecell() - Generic xlate for direct one cell bindings
904  *
905  * Device Tree IRQ specifier translation function which works with one cell
906  * bindings where the cell value maps directly to the hwirq number.
907  */
908 int irq_domain_xlate_onecell(struct irq_domain *d, struct device_node *ctrlr,
909 			     const u32 *intspec, unsigned int intsize,
910 			     unsigned long *out_hwirq, unsigned int *out_type)
911 {
912 	if (WARN_ON(intsize < 1))
913 		return -EINVAL;
914 	*out_hwirq = intspec[0];
915 	*out_type = IRQ_TYPE_NONE;
916 	return 0;
917 }
918 EXPORT_SYMBOL_GPL(irq_domain_xlate_onecell);
919 
920 /**
921  * irq_domain_xlate_twocell() - Generic xlate for direct two cell bindings
922  *
923  * Device Tree IRQ specifier translation function which works with two cell
924  * bindings where the cell values map directly to the hwirq number
925  * and linux irq flags.
926  */
927 int irq_domain_xlate_twocell(struct irq_domain *d, struct device_node *ctrlr,
928 			const u32 *intspec, unsigned int intsize,
929 			irq_hw_number_t *out_hwirq, unsigned int *out_type)
930 {
931 	if (WARN_ON(intsize < 2))
932 		return -EINVAL;
933 	*out_hwirq = intspec[0];
934 	*out_type = intspec[1] & IRQ_TYPE_SENSE_MASK;
935 	return 0;
936 }
937 EXPORT_SYMBOL_GPL(irq_domain_xlate_twocell);
938 
939 /**
940  * irq_domain_xlate_onetwocell() - Generic xlate for one or two cell bindings
941  *
942  * Device Tree IRQ specifier translation function which works with either one
943  * or two cell bindings where the cell values map directly to the hwirq number
944  * and linux irq flags.
945  *
946  * Note: don't use this function unless your interrupt controller explicitly
947  * supports both one and two cell bindings.  For the majority of controllers
948  * the _onecell() or _twocell() variants above should be used.
949  */
950 int irq_domain_xlate_onetwocell(struct irq_domain *d,
951 				struct device_node *ctrlr,
952 				const u32 *intspec, unsigned int intsize,
953 				unsigned long *out_hwirq, unsigned int *out_type)
954 {
955 	if (WARN_ON(intsize < 1))
956 		return -EINVAL;
957 	*out_hwirq = intspec[0];
958 	if (intsize > 1)
959 		*out_type = intspec[1] & IRQ_TYPE_SENSE_MASK;
960 	else
961 		*out_type = IRQ_TYPE_NONE;
962 	return 0;
963 }
964 EXPORT_SYMBOL_GPL(irq_domain_xlate_onetwocell);
965 
966 const struct irq_domain_ops irq_domain_simple_ops = {
967 	.xlate = irq_domain_xlate_onetwocell,
968 };
969 EXPORT_SYMBOL_GPL(irq_domain_simple_ops);
970 
971 int irq_domain_alloc_descs(int virq, unsigned int cnt, irq_hw_number_t hwirq,
972 			   int node, const struct cpumask *affinity)
973 {
974 	unsigned int hint;
975 
976 	if (virq >= 0) {
977 		virq = __irq_alloc_descs(virq, virq, cnt, node, THIS_MODULE,
978 					 affinity);
979 	} else {
980 		hint = hwirq % nr_irqs;
981 		if (hint == 0)
982 			hint++;
983 		virq = __irq_alloc_descs(-1, hint, cnt, node, THIS_MODULE,
984 					 affinity);
985 		if (virq <= 0 && hint > 1) {
986 			virq = __irq_alloc_descs(-1, 1, cnt, node, THIS_MODULE,
987 						 affinity);
988 		}
989 	}
990 
991 	return virq;
992 }
993 
994 #ifdef	CONFIG_IRQ_DOMAIN_HIERARCHY
995 /**
996  * irq_domain_create_hierarchy - Add a irqdomain into the hierarchy
997  * @parent:	Parent irq domain to associate with the new domain
998  * @flags:	Irq domain flags associated to the domain
999  * @size:	Size of the domain. See below
1000  * @fwnode:	Optional fwnode of the interrupt controller
1001  * @ops:	Pointer to the interrupt domain callbacks
1002  * @host_data:	Controller private data pointer
1003  *
1004  * If @size is 0 a tree domain is created, otherwise a linear domain.
1005  *
1006  * If successful the parent is associated to the new domain and the
1007  * domain flags are set.
1008  * Returns pointer to IRQ domain, or NULL on failure.
1009  */
1010 struct irq_domain *irq_domain_create_hierarchy(struct irq_domain *parent,
1011 					    unsigned int flags,
1012 					    unsigned int size,
1013 					    struct fwnode_handle *fwnode,
1014 					    const struct irq_domain_ops *ops,
1015 					    void *host_data)
1016 {
1017 	struct irq_domain *domain;
1018 
1019 	if (size)
1020 		domain = irq_domain_create_linear(fwnode, size, ops, host_data);
1021 	else
1022 		domain = irq_domain_create_tree(fwnode, ops, host_data);
1023 	if (domain) {
1024 		domain->parent = parent;
1025 		domain->flags |= flags;
1026 	}
1027 
1028 	return domain;
1029 }
1030 EXPORT_SYMBOL_GPL(irq_domain_create_hierarchy);
1031 
1032 static void irq_domain_insert_irq(int virq)
1033 {
1034 	struct irq_data *data;
1035 
1036 	for (data = irq_get_irq_data(virq); data; data = data->parent_data) {
1037 		struct irq_domain *domain = data->domain;
1038 
1039 		domain->mapcount++;
1040 		irq_domain_set_mapping(domain, data->hwirq, data);
1041 
1042 		/* If not already assigned, give the domain the chip's name */
1043 		if (!domain->name && data->chip)
1044 			domain->name = data->chip->name;
1045 	}
1046 
1047 	irq_clear_status_flags(virq, IRQ_NOREQUEST);
1048 }
1049 
1050 static void irq_domain_remove_irq(int virq)
1051 {
1052 	struct irq_data *data;
1053 
1054 	irq_set_status_flags(virq, IRQ_NOREQUEST);
1055 	irq_set_chip_and_handler(virq, NULL, NULL);
1056 	synchronize_irq(virq);
1057 	smp_mb();
1058 
1059 	for (data = irq_get_irq_data(virq); data; data = data->parent_data) {
1060 		struct irq_domain *domain = data->domain;
1061 		irq_hw_number_t hwirq = data->hwirq;
1062 
1063 		domain->mapcount--;
1064 		irq_domain_clear_mapping(domain, hwirq);
1065 	}
1066 }
1067 
1068 static struct irq_data *irq_domain_insert_irq_data(struct irq_domain *domain,
1069 						   struct irq_data *child)
1070 {
1071 	struct irq_data *irq_data;
1072 
1073 	irq_data = kzalloc_node(sizeof(*irq_data), GFP_KERNEL,
1074 				irq_data_get_node(child));
1075 	if (irq_data) {
1076 		child->parent_data = irq_data;
1077 		irq_data->irq = child->irq;
1078 		irq_data->common = child->common;
1079 		irq_data->domain = domain;
1080 	}
1081 
1082 	return irq_data;
1083 }
1084 
1085 static void irq_domain_free_irq_data(unsigned int virq, unsigned int nr_irqs)
1086 {
1087 	struct irq_data *irq_data, *tmp;
1088 	int i;
1089 
1090 	for (i = 0; i < nr_irqs; i++) {
1091 		irq_data = irq_get_irq_data(virq + i);
1092 		tmp = irq_data->parent_data;
1093 		irq_data->parent_data = NULL;
1094 		irq_data->domain = NULL;
1095 
1096 		while (tmp) {
1097 			irq_data = tmp;
1098 			tmp = tmp->parent_data;
1099 			kfree(irq_data);
1100 		}
1101 	}
1102 }
1103 
1104 static int irq_domain_alloc_irq_data(struct irq_domain *domain,
1105 				     unsigned int virq, unsigned int nr_irqs)
1106 {
1107 	struct irq_data *irq_data;
1108 	struct irq_domain *parent;
1109 	int i;
1110 
1111 	/* The outermost irq_data is embedded in struct irq_desc */
1112 	for (i = 0; i < nr_irqs; i++) {
1113 		irq_data = irq_get_irq_data(virq + i);
1114 		irq_data->domain = domain;
1115 
1116 		for (parent = domain->parent; parent; parent = parent->parent) {
1117 			irq_data = irq_domain_insert_irq_data(parent, irq_data);
1118 			if (!irq_data) {
1119 				irq_domain_free_irq_data(virq, i + 1);
1120 				return -ENOMEM;
1121 			}
1122 		}
1123 	}
1124 
1125 	return 0;
1126 }
1127 
1128 /**
1129  * irq_domain_get_irq_data - Get irq_data associated with @virq and @domain
1130  * @domain:	domain to match
1131  * @virq:	IRQ number to get irq_data
1132  */
1133 struct irq_data *irq_domain_get_irq_data(struct irq_domain *domain,
1134 					 unsigned int virq)
1135 {
1136 	struct irq_data *irq_data;
1137 
1138 	for (irq_data = irq_get_irq_data(virq); irq_data;
1139 	     irq_data = irq_data->parent_data)
1140 		if (irq_data->domain == domain)
1141 			return irq_data;
1142 
1143 	return NULL;
1144 }
1145 EXPORT_SYMBOL_GPL(irq_domain_get_irq_data);
1146 
1147 /**
1148  * irq_domain_set_hwirq_and_chip - Set hwirq and irqchip of @virq at @domain
1149  * @domain:	Interrupt domain to match
1150  * @virq:	IRQ number
1151  * @hwirq:	The hwirq number
1152  * @chip:	The associated interrupt chip
1153  * @chip_data:	The associated chip data
1154  */
1155 int irq_domain_set_hwirq_and_chip(struct irq_domain *domain, unsigned int virq,
1156 				  irq_hw_number_t hwirq, struct irq_chip *chip,
1157 				  void *chip_data)
1158 {
1159 	struct irq_data *irq_data = irq_domain_get_irq_data(domain, virq);
1160 
1161 	if (!irq_data)
1162 		return -ENOENT;
1163 
1164 	irq_data->hwirq = hwirq;
1165 	irq_data->chip = chip ? chip : &no_irq_chip;
1166 	irq_data->chip_data = chip_data;
1167 
1168 	return 0;
1169 }
1170 EXPORT_SYMBOL_GPL(irq_domain_set_hwirq_and_chip);
1171 
1172 /**
1173  * irq_domain_set_info - Set the complete data for a @virq in @domain
1174  * @domain:		Interrupt domain to match
1175  * @virq:		IRQ number
1176  * @hwirq:		The hardware interrupt number
1177  * @chip:		The associated interrupt chip
1178  * @chip_data:		The associated interrupt chip data
1179  * @handler:		The interrupt flow handler
1180  * @handler_data:	The interrupt flow handler data
1181  * @handler_name:	The interrupt handler name
1182  */
1183 void irq_domain_set_info(struct irq_domain *domain, unsigned int virq,
1184 			 irq_hw_number_t hwirq, struct irq_chip *chip,
1185 			 void *chip_data, irq_flow_handler_t handler,
1186 			 void *handler_data, const char *handler_name)
1187 {
1188 	irq_domain_set_hwirq_and_chip(domain, virq, hwirq, chip, chip_data);
1189 	__irq_set_handler(virq, handler, 0, handler_name);
1190 	irq_set_handler_data(virq, handler_data);
1191 }
1192 EXPORT_SYMBOL(irq_domain_set_info);
1193 
1194 /**
1195  * irq_domain_reset_irq_data - Clear hwirq, chip and chip_data in @irq_data
1196  * @irq_data:	The pointer to irq_data
1197  */
1198 void irq_domain_reset_irq_data(struct irq_data *irq_data)
1199 {
1200 	irq_data->hwirq = 0;
1201 	irq_data->chip = &no_irq_chip;
1202 	irq_data->chip_data = NULL;
1203 }
1204 EXPORT_SYMBOL_GPL(irq_domain_reset_irq_data);
1205 
1206 /**
1207  * irq_domain_free_irqs_common - Clear irq_data and free the parent
1208  * @domain:	Interrupt domain to match
1209  * @virq:	IRQ number to start with
1210  * @nr_irqs:	The number of irqs to free
1211  */
1212 void irq_domain_free_irqs_common(struct irq_domain *domain, unsigned int virq,
1213 				 unsigned int nr_irqs)
1214 {
1215 	struct irq_data *irq_data;
1216 	int i;
1217 
1218 	for (i = 0; i < nr_irqs; i++) {
1219 		irq_data = irq_domain_get_irq_data(domain, virq + i);
1220 		if (irq_data)
1221 			irq_domain_reset_irq_data(irq_data);
1222 	}
1223 	irq_domain_free_irqs_parent(domain, virq, nr_irqs);
1224 }
1225 EXPORT_SYMBOL_GPL(irq_domain_free_irqs_common);
1226 
1227 /**
1228  * irq_domain_free_irqs_top - Clear handler and handler data, clear irqdata and free parent
1229  * @domain:	Interrupt domain to match
1230  * @virq:	IRQ number to start with
1231  * @nr_irqs:	The number of irqs to free
1232  */
1233 void irq_domain_free_irqs_top(struct irq_domain *domain, unsigned int virq,
1234 			      unsigned int nr_irqs)
1235 {
1236 	int i;
1237 
1238 	for (i = 0; i < nr_irqs; i++) {
1239 		irq_set_handler_data(virq + i, NULL);
1240 		irq_set_handler(virq + i, NULL);
1241 	}
1242 	irq_domain_free_irqs_common(domain, virq, nr_irqs);
1243 }
1244 
1245 static void irq_domain_free_irqs_hierarchy(struct irq_domain *domain,
1246 					   unsigned int irq_base,
1247 					   unsigned int nr_irqs)
1248 {
1249 	if (domain->ops->free)
1250 		domain->ops->free(domain, irq_base, nr_irqs);
1251 }
1252 
1253 int irq_domain_alloc_irqs_hierarchy(struct irq_domain *domain,
1254 				    unsigned int irq_base,
1255 				    unsigned int nr_irqs, void *arg)
1256 {
1257 	return domain->ops->alloc(domain, irq_base, nr_irqs, arg);
1258 }
1259 
1260 /**
1261  * __irq_domain_alloc_irqs - Allocate IRQs from domain
1262  * @domain:	domain to allocate from
1263  * @irq_base:	allocate specified IRQ nubmer if irq_base >= 0
1264  * @nr_irqs:	number of IRQs to allocate
1265  * @node:	NUMA node id for memory allocation
1266  * @arg:	domain specific argument
1267  * @realloc:	IRQ descriptors have already been allocated if true
1268  * @affinity:	Optional irq affinity mask for multiqueue devices
1269  *
1270  * Allocate IRQ numbers and initialized all data structures to support
1271  * hierarchy IRQ domains.
1272  * Parameter @realloc is mainly to support legacy IRQs.
1273  * Returns error code or allocated IRQ number
1274  *
1275  * The whole process to setup an IRQ has been split into two steps.
1276  * The first step, __irq_domain_alloc_irqs(), is to allocate IRQ
1277  * descriptor and required hardware resources. The second step,
1278  * irq_domain_activate_irq(), is to program hardwares with preallocated
1279  * resources. In this way, it's easier to rollback when failing to
1280  * allocate resources.
1281  */
1282 int __irq_domain_alloc_irqs(struct irq_domain *domain, int irq_base,
1283 			    unsigned int nr_irqs, int node, void *arg,
1284 			    bool realloc, const struct cpumask *affinity)
1285 {
1286 	int i, ret, virq;
1287 
1288 	if (domain == NULL) {
1289 		domain = irq_default_domain;
1290 		if (WARN(!domain, "domain is NULL; cannot allocate IRQ\n"))
1291 			return -EINVAL;
1292 	}
1293 
1294 	if (!domain->ops->alloc) {
1295 		pr_debug("domain->ops->alloc() is NULL\n");
1296 		return -ENOSYS;
1297 	}
1298 
1299 	if (realloc && irq_base >= 0) {
1300 		virq = irq_base;
1301 	} else {
1302 		virq = irq_domain_alloc_descs(irq_base, nr_irqs, 0, node,
1303 					      affinity);
1304 		if (virq < 0) {
1305 			pr_debug("cannot allocate IRQ(base %d, count %d)\n",
1306 				 irq_base, nr_irqs);
1307 			return virq;
1308 		}
1309 	}
1310 
1311 	if (irq_domain_alloc_irq_data(domain, virq, nr_irqs)) {
1312 		pr_debug("cannot allocate memory for IRQ%d\n", virq);
1313 		ret = -ENOMEM;
1314 		goto out_free_desc;
1315 	}
1316 
1317 	mutex_lock(&irq_domain_mutex);
1318 	ret = irq_domain_alloc_irqs_hierarchy(domain, virq, nr_irqs, arg);
1319 	if (ret < 0) {
1320 		mutex_unlock(&irq_domain_mutex);
1321 		goto out_free_irq_data;
1322 	}
1323 	for (i = 0; i < nr_irqs; i++)
1324 		irq_domain_insert_irq(virq + i);
1325 	mutex_unlock(&irq_domain_mutex);
1326 
1327 	return virq;
1328 
1329 out_free_irq_data:
1330 	irq_domain_free_irq_data(virq, nr_irqs);
1331 out_free_desc:
1332 	irq_free_descs(virq, nr_irqs);
1333 	return ret;
1334 }
1335 
1336 /* The irq_data was moved, fix the revmap to refer to the new location */
1337 static void irq_domain_fix_revmap(struct irq_data *d)
1338 {
1339 	void __rcu **slot;
1340 
1341 	if (d->hwirq < d->domain->revmap_size)
1342 		return; /* Not using radix tree. */
1343 
1344 	/* Fix up the revmap. */
1345 	mutex_lock(&d->domain->revmap_tree_mutex);
1346 	slot = radix_tree_lookup_slot(&d->domain->revmap_tree, d->hwirq);
1347 	if (slot)
1348 		radix_tree_replace_slot(&d->domain->revmap_tree, slot, d);
1349 	mutex_unlock(&d->domain->revmap_tree_mutex);
1350 }
1351 
1352 /**
1353  * irq_domain_push_irq() - Push a domain in to the top of a hierarchy.
1354  * @domain:	Domain to push.
1355  * @virq:	Irq to push the domain in to.
1356  * @arg:	Passed to the irq_domain_ops alloc() function.
1357  *
1358  * For an already existing irqdomain hierarchy, as might be obtained
1359  * via a call to pci_enable_msix(), add an additional domain to the
1360  * head of the processing chain.  Must be called before request_irq()
1361  * has been called.
1362  */
1363 int irq_domain_push_irq(struct irq_domain *domain, int virq, void *arg)
1364 {
1365 	struct irq_data *child_irq_data;
1366 	struct irq_data *root_irq_data = irq_get_irq_data(virq);
1367 	struct irq_desc *desc;
1368 	int rv = 0;
1369 
1370 	/*
1371 	 * Check that no action has been set, which indicates the virq
1372 	 * is in a state where this function doesn't have to deal with
1373 	 * races between interrupt handling and maintaining the
1374 	 * hierarchy.  This will catch gross misuse.  Attempting to
1375 	 * make the check race free would require holding locks across
1376 	 * calls to struct irq_domain_ops->alloc(), which could lead
1377 	 * to deadlock, so we just do a simple check before starting.
1378 	 */
1379 	desc = irq_to_desc(virq);
1380 	if (!desc)
1381 		return -EINVAL;
1382 	if (WARN_ON(desc->action))
1383 		return -EBUSY;
1384 
1385 	if (domain == NULL)
1386 		return -EINVAL;
1387 
1388 	if (WARN_ON(!irq_domain_is_hierarchy(domain)))
1389 		return -EINVAL;
1390 
1391 	if (!root_irq_data)
1392 		return -EINVAL;
1393 
1394 	if (domain->parent != root_irq_data->domain)
1395 		return -EINVAL;
1396 
1397 	child_irq_data = kzalloc_node(sizeof(*child_irq_data), GFP_KERNEL,
1398 				      irq_data_get_node(root_irq_data));
1399 	if (!child_irq_data)
1400 		return -ENOMEM;
1401 
1402 	mutex_lock(&irq_domain_mutex);
1403 
1404 	/* Copy the original irq_data. */
1405 	*child_irq_data = *root_irq_data;
1406 
1407 	/*
1408 	 * Overwrite the root_irq_data, which is embedded in struct
1409 	 * irq_desc, with values for this domain.
1410 	 */
1411 	root_irq_data->parent_data = child_irq_data;
1412 	root_irq_data->domain = domain;
1413 	root_irq_data->mask = 0;
1414 	root_irq_data->hwirq = 0;
1415 	root_irq_data->chip = NULL;
1416 	root_irq_data->chip_data = NULL;
1417 
1418 	/* May (probably does) set hwirq, chip, etc. */
1419 	rv = irq_domain_alloc_irqs_hierarchy(domain, virq, 1, arg);
1420 	if (rv) {
1421 		/* Restore the original irq_data. */
1422 		*root_irq_data = *child_irq_data;
1423 		goto error;
1424 	}
1425 
1426 	irq_domain_fix_revmap(child_irq_data);
1427 	irq_domain_set_mapping(domain, root_irq_data->hwirq, root_irq_data);
1428 
1429 error:
1430 	mutex_unlock(&irq_domain_mutex);
1431 
1432 	return rv;
1433 }
1434 EXPORT_SYMBOL_GPL(irq_domain_push_irq);
1435 
1436 /**
1437  * irq_domain_pop_irq() - Remove a domain from the top of a hierarchy.
1438  * @domain:	Domain to remove.
1439  * @virq:	Irq to remove the domain from.
1440  *
1441  * Undo the effects of a call to irq_domain_push_irq().  Must be
1442  * called either before request_irq() or after free_irq().
1443  */
1444 int irq_domain_pop_irq(struct irq_domain *domain, int virq)
1445 {
1446 	struct irq_data *root_irq_data = irq_get_irq_data(virq);
1447 	struct irq_data *child_irq_data;
1448 	struct irq_data *tmp_irq_data;
1449 	struct irq_desc *desc;
1450 
1451 	/*
1452 	 * Check that no action is set, which indicates the virq is in
1453 	 * a state where this function doesn't have to deal with races
1454 	 * between interrupt handling and maintaining the hierarchy.
1455 	 * This will catch gross misuse.  Attempting to make the check
1456 	 * race free would require holding locks across calls to
1457 	 * struct irq_domain_ops->free(), which could lead to
1458 	 * deadlock, so we just do a simple check before starting.
1459 	 */
1460 	desc = irq_to_desc(virq);
1461 	if (!desc)
1462 		return -EINVAL;
1463 	if (WARN_ON(desc->action))
1464 		return -EBUSY;
1465 
1466 	if (domain == NULL)
1467 		return -EINVAL;
1468 
1469 	if (!root_irq_data)
1470 		return -EINVAL;
1471 
1472 	tmp_irq_data = irq_domain_get_irq_data(domain, virq);
1473 
1474 	/* We can only "pop" if this domain is at the top of the list */
1475 	if (WARN_ON(root_irq_data != tmp_irq_data))
1476 		return -EINVAL;
1477 
1478 	if (WARN_ON(root_irq_data->domain != domain))
1479 		return -EINVAL;
1480 
1481 	child_irq_data = root_irq_data->parent_data;
1482 	if (WARN_ON(!child_irq_data))
1483 		return -EINVAL;
1484 
1485 	mutex_lock(&irq_domain_mutex);
1486 
1487 	root_irq_data->parent_data = NULL;
1488 
1489 	irq_domain_clear_mapping(domain, root_irq_data->hwirq);
1490 	irq_domain_free_irqs_hierarchy(domain, virq, 1);
1491 
1492 	/* Restore the original irq_data. */
1493 	*root_irq_data = *child_irq_data;
1494 
1495 	irq_domain_fix_revmap(root_irq_data);
1496 
1497 	mutex_unlock(&irq_domain_mutex);
1498 
1499 	kfree(child_irq_data);
1500 
1501 	return 0;
1502 }
1503 EXPORT_SYMBOL_GPL(irq_domain_pop_irq);
1504 
1505 /**
1506  * irq_domain_free_irqs - Free IRQ number and associated data structures
1507  * @virq:	base IRQ number
1508  * @nr_irqs:	number of IRQs to free
1509  */
1510 void irq_domain_free_irqs(unsigned int virq, unsigned int nr_irqs)
1511 {
1512 	struct irq_data *data = irq_get_irq_data(virq);
1513 	int i;
1514 
1515 	if (WARN(!data || !data->domain || !data->domain->ops->free,
1516 		 "NULL pointer, cannot free irq\n"))
1517 		return;
1518 
1519 	mutex_lock(&irq_domain_mutex);
1520 	for (i = 0; i < nr_irqs; i++)
1521 		irq_domain_remove_irq(virq + i);
1522 	irq_domain_free_irqs_hierarchy(data->domain, virq, nr_irqs);
1523 	mutex_unlock(&irq_domain_mutex);
1524 
1525 	irq_domain_free_irq_data(virq, nr_irqs);
1526 	irq_free_descs(virq, nr_irqs);
1527 }
1528 
1529 /**
1530  * irq_domain_alloc_irqs_parent - Allocate interrupts from parent domain
1531  * @irq_base:	Base IRQ number
1532  * @nr_irqs:	Number of IRQs to allocate
1533  * @arg:	Allocation data (arch/domain specific)
1534  *
1535  * Check whether the domain has been setup recursive. If not allocate
1536  * through the parent domain.
1537  */
1538 int irq_domain_alloc_irqs_parent(struct irq_domain *domain,
1539 				 unsigned int irq_base, unsigned int nr_irqs,
1540 				 void *arg)
1541 {
1542 	if (!domain->parent)
1543 		return -ENOSYS;
1544 
1545 	return irq_domain_alloc_irqs_hierarchy(domain->parent, irq_base,
1546 					       nr_irqs, arg);
1547 }
1548 EXPORT_SYMBOL_GPL(irq_domain_alloc_irqs_parent);
1549 
1550 /**
1551  * irq_domain_free_irqs_parent - Free interrupts from parent domain
1552  * @irq_base:	Base IRQ number
1553  * @nr_irqs:	Number of IRQs to free
1554  *
1555  * Check whether the domain has been setup recursive. If not free
1556  * through the parent domain.
1557  */
1558 void irq_domain_free_irqs_parent(struct irq_domain *domain,
1559 				 unsigned int irq_base, unsigned int nr_irqs)
1560 {
1561 	if (!domain->parent)
1562 		return;
1563 
1564 	irq_domain_free_irqs_hierarchy(domain->parent, irq_base, nr_irqs);
1565 }
1566 EXPORT_SYMBOL_GPL(irq_domain_free_irqs_parent);
1567 
1568 static void __irq_domain_deactivate_irq(struct irq_data *irq_data)
1569 {
1570 	if (irq_data && irq_data->domain) {
1571 		struct irq_domain *domain = irq_data->domain;
1572 
1573 		if (domain->ops->deactivate)
1574 			domain->ops->deactivate(domain, irq_data);
1575 		if (irq_data->parent_data)
1576 			__irq_domain_deactivate_irq(irq_data->parent_data);
1577 	}
1578 }
1579 
1580 static int __irq_domain_activate_irq(struct irq_data *irqd, bool reserve)
1581 {
1582 	int ret = 0;
1583 
1584 	if (irqd && irqd->domain) {
1585 		struct irq_domain *domain = irqd->domain;
1586 
1587 		if (irqd->parent_data)
1588 			ret = __irq_domain_activate_irq(irqd->parent_data,
1589 							reserve);
1590 		if (!ret && domain->ops->activate) {
1591 			ret = domain->ops->activate(domain, irqd, reserve);
1592 			/* Rollback in case of error */
1593 			if (ret && irqd->parent_data)
1594 				__irq_domain_deactivate_irq(irqd->parent_data);
1595 		}
1596 	}
1597 	return ret;
1598 }
1599 
1600 /**
1601  * irq_domain_activate_irq - Call domain_ops->activate recursively to activate
1602  *			     interrupt
1603  * @irq_data:	Outermost irq_data associated with interrupt
1604  * @reserve:	If set only reserve an interrupt vector instead of assigning one
1605  *
1606  * This is the second step to call domain_ops->activate to program interrupt
1607  * controllers, so the interrupt could actually get delivered.
1608  */
1609 int irq_domain_activate_irq(struct irq_data *irq_data, bool reserve)
1610 {
1611 	int ret = 0;
1612 
1613 	if (!irqd_is_activated(irq_data))
1614 		ret = __irq_domain_activate_irq(irq_data, reserve);
1615 	if (!ret)
1616 		irqd_set_activated(irq_data);
1617 	return ret;
1618 }
1619 
1620 /**
1621  * irq_domain_deactivate_irq - Call domain_ops->deactivate recursively to
1622  *			       deactivate interrupt
1623  * @irq_data: outermost irq_data associated with interrupt
1624  *
1625  * It calls domain_ops->deactivate to program interrupt controllers to disable
1626  * interrupt delivery.
1627  */
1628 void irq_domain_deactivate_irq(struct irq_data *irq_data)
1629 {
1630 	if (irqd_is_activated(irq_data)) {
1631 		__irq_domain_deactivate_irq(irq_data);
1632 		irqd_clr_activated(irq_data);
1633 	}
1634 }
1635 
1636 static void irq_domain_check_hierarchy(struct irq_domain *domain)
1637 {
1638 	/* Hierarchy irq_domains must implement callback alloc() */
1639 	if (domain->ops->alloc)
1640 		domain->flags |= IRQ_DOMAIN_FLAG_HIERARCHY;
1641 }
1642 
1643 /**
1644  * irq_domain_hierarchical_is_msi_remap - Check if the domain or any
1645  * parent has MSI remapping support
1646  * @domain: domain pointer
1647  */
1648 bool irq_domain_hierarchical_is_msi_remap(struct irq_domain *domain)
1649 {
1650 	for (; domain; domain = domain->parent) {
1651 		if (irq_domain_is_msi_remap(domain))
1652 			return true;
1653 	}
1654 	return false;
1655 }
1656 #else	/* CONFIG_IRQ_DOMAIN_HIERARCHY */
1657 /**
1658  * irq_domain_get_irq_data - Get irq_data associated with @virq and @domain
1659  * @domain:	domain to match
1660  * @virq:	IRQ number to get irq_data
1661  */
1662 struct irq_data *irq_domain_get_irq_data(struct irq_domain *domain,
1663 					 unsigned int virq)
1664 {
1665 	struct irq_data *irq_data = irq_get_irq_data(virq);
1666 
1667 	return (irq_data && irq_data->domain == domain) ? irq_data : NULL;
1668 }
1669 EXPORT_SYMBOL_GPL(irq_domain_get_irq_data);
1670 
1671 /**
1672  * irq_domain_set_info - Set the complete data for a @virq in @domain
1673  * @domain:		Interrupt domain to match
1674  * @virq:		IRQ number
1675  * @hwirq:		The hardware interrupt number
1676  * @chip:		The associated interrupt chip
1677  * @chip_data:		The associated interrupt chip data
1678  * @handler:		The interrupt flow handler
1679  * @handler_data:	The interrupt flow handler data
1680  * @handler_name:	The interrupt handler name
1681  */
1682 void irq_domain_set_info(struct irq_domain *domain, unsigned int virq,
1683 			 irq_hw_number_t hwirq, struct irq_chip *chip,
1684 			 void *chip_data, irq_flow_handler_t handler,
1685 			 void *handler_data, const char *handler_name)
1686 {
1687 	irq_set_chip_and_handler_name(virq, chip, handler, handler_name);
1688 	irq_set_chip_data(virq, chip_data);
1689 	irq_set_handler_data(virq, handler_data);
1690 }
1691 
1692 static void irq_domain_check_hierarchy(struct irq_domain *domain)
1693 {
1694 }
1695 #endif	/* CONFIG_IRQ_DOMAIN_HIERARCHY */
1696 
1697 #ifdef CONFIG_GENERIC_IRQ_DEBUGFS
1698 static struct dentry *domain_dir;
1699 
1700 static void
1701 irq_domain_debug_show_one(struct seq_file *m, struct irq_domain *d, int ind)
1702 {
1703 	seq_printf(m, "%*sname:   %s\n", ind, "", d->name);
1704 	seq_printf(m, "%*ssize:   %u\n", ind + 1, "",
1705 		   d->revmap_size + d->revmap_direct_max_irq);
1706 	seq_printf(m, "%*smapped: %u\n", ind + 1, "", d->mapcount);
1707 	seq_printf(m, "%*sflags:  0x%08x\n", ind +1 , "", d->flags);
1708 	if (d->ops && d->ops->debug_show)
1709 		d->ops->debug_show(m, d, NULL, ind + 1);
1710 #ifdef	CONFIG_IRQ_DOMAIN_HIERARCHY
1711 	if (!d->parent)
1712 		return;
1713 	seq_printf(m, "%*sparent: %s\n", ind + 1, "", d->parent->name);
1714 	irq_domain_debug_show_one(m, d->parent, ind + 4);
1715 #endif
1716 }
1717 
1718 static int irq_domain_debug_show(struct seq_file *m, void *p)
1719 {
1720 	struct irq_domain *d = m->private;
1721 
1722 	/* Default domain? Might be NULL */
1723 	if (!d) {
1724 		if (!irq_default_domain)
1725 			return 0;
1726 		d = irq_default_domain;
1727 	}
1728 	irq_domain_debug_show_one(m, d, 0);
1729 	return 0;
1730 }
1731 DEFINE_SHOW_ATTRIBUTE(irq_domain_debug);
1732 
1733 static void debugfs_add_domain_dir(struct irq_domain *d)
1734 {
1735 	if (!d->name || !domain_dir || d->debugfs_file)
1736 		return;
1737 	d->debugfs_file = debugfs_create_file(d->name, 0444, domain_dir, d,
1738 					      &irq_domain_debug_fops);
1739 }
1740 
1741 static void debugfs_remove_domain_dir(struct irq_domain *d)
1742 {
1743 	debugfs_remove(d->debugfs_file);
1744 }
1745 
1746 void __init irq_domain_debugfs_init(struct dentry *root)
1747 {
1748 	struct irq_domain *d;
1749 
1750 	domain_dir = debugfs_create_dir("domains", root);
1751 	if (!domain_dir)
1752 		return;
1753 
1754 	debugfs_create_file("default", 0444, domain_dir, NULL,
1755 			    &irq_domain_debug_fops);
1756 	mutex_lock(&irq_domain_mutex);
1757 	list_for_each_entry(d, &irq_domain_list, link)
1758 		debugfs_add_domain_dir(d);
1759 	mutex_unlock(&irq_domain_mutex);
1760 }
1761 #endif
1762