1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  *  Derived from arch/i386/kernel/irq.c
4  *    Copyright (C) 1992 Linus Torvalds
5  *  Adapted from arch/i386 by Gary Thomas
6  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
7  *  Updated and modified by Cort Dougan <cort@fsmlabs.com>
8  *    Copyright (C) 1996-2001 Cort Dougan
9  *  Adapted for Power Macintosh by Paul Mackerras
10  *    Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au)
11  *
12  * This file contains the code used to make IRQ descriptions in the
13  * device tree to actual irq numbers on an interrupt controller
14  * driver.
15  */
16 
17 #define pr_fmt(fmt)	"OF: " fmt
18 
19 #include <linux/device.h>
20 #include <linux/errno.h>
21 #include <linux/list.h>
22 #include <linux/module.h>
23 #include <linux/of.h>
24 #include <linux/of_irq.h>
25 #include <linux/of_pci.h>
26 #include <linux/string.h>
27 #include <linux/slab.h>
28 
29 /**
30  * irq_of_parse_and_map - Parse and map an interrupt into linux virq space
31  * @dev: Device node of the device whose interrupt is to be mapped
32  * @index: Index of the interrupt to map
33  *
34  * This function is a wrapper that chains of_irq_parse_one() and
35  * irq_create_of_mapping() to make things easier to callers
36  */
irq_of_parse_and_map(struct device_node * dev,int index)37 unsigned int irq_of_parse_and_map(struct device_node *dev, int index)
38 {
39 	struct of_phandle_args oirq;
40 
41 	if (of_irq_parse_one(dev, index, &oirq))
42 		return 0;
43 
44 	return irq_create_of_mapping(&oirq);
45 }
46 EXPORT_SYMBOL_GPL(irq_of_parse_and_map);
47 
48 /**
49  * of_irq_find_parent - Given a device node, find its interrupt parent node
50  * @child: pointer to device node
51  *
52  * Returns a pointer to the interrupt parent node, or NULL if the interrupt
53  * parent could not be determined.
54  */
of_irq_find_parent(struct device_node * child)55 struct device_node *of_irq_find_parent(struct device_node *child)
56 {
57 	struct device_node *p;
58 	phandle parent;
59 
60 	if (!of_node_get(child))
61 		return NULL;
62 
63 	do {
64 		if (of_property_read_u32(child, "interrupt-parent", &parent)) {
65 			p = of_get_parent(child);
66 		} else	{
67 			if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
68 				p = of_node_get(of_irq_dflt_pic);
69 			else
70 				p = of_find_node_by_phandle(parent);
71 		}
72 		of_node_put(child);
73 		child = p;
74 	} while (p && of_get_property(p, "#interrupt-cells", NULL) == NULL);
75 
76 	return p;
77 }
78 EXPORT_SYMBOL_GPL(of_irq_find_parent);
79 
80 /**
81  * of_irq_parse_raw - Low level interrupt tree parsing
82  * @addr:	address specifier (start of "reg" property of the device) in be32 format
83  * @out_irq:	structure of_phandle_args updated by this function
84  *
85  * Returns 0 on success and a negative number on error
86  *
87  * This function is a low-level interrupt tree walking function. It
88  * can be used to do a partial walk with synthetized reg and interrupts
89  * properties, for example when resolving PCI interrupts when no device
90  * node exist for the parent. It takes an interrupt specifier structure as
91  * input, walks the tree looking for any interrupt-map properties, translates
92  * the specifier for each map, and then returns the translated map.
93  */
of_irq_parse_raw(const __be32 * addr,struct of_phandle_args * out_irq)94 int of_irq_parse_raw(const __be32 *addr, struct of_phandle_args *out_irq)
95 {
96 	struct device_node *ipar, *tnode, *old = NULL, *newpar = NULL;
97 	__be32 initial_match_array[MAX_PHANDLE_ARGS];
98 	const __be32 *match_array = initial_match_array;
99 	const __be32 *tmp, *imap, *imask, dummy_imask[] = { [0 ... MAX_PHANDLE_ARGS] = cpu_to_be32(~0) };
100 	u32 intsize = 1, addrsize, newintsize = 0, newaddrsize = 0;
101 	int imaplen, match, i, rc = -EINVAL;
102 
103 #ifdef DEBUG
104 	of_print_phandle_args("of_irq_parse_raw: ", out_irq);
105 #endif
106 
107 	ipar = of_node_get(out_irq->np);
108 
109 	/* First get the #interrupt-cells property of the current cursor
110 	 * that tells us how to interpret the passed-in intspec. If there
111 	 * is none, we are nice and just walk up the tree
112 	 */
113 	do {
114 		if (!of_property_read_u32(ipar, "#interrupt-cells", &intsize))
115 			break;
116 		tnode = ipar;
117 		ipar = of_irq_find_parent(ipar);
118 		of_node_put(tnode);
119 	} while (ipar);
120 	if (ipar == NULL) {
121 		pr_debug(" -> no parent found !\n");
122 		goto fail;
123 	}
124 
125 	pr_debug("of_irq_parse_raw: ipar=%pOF, size=%d\n", ipar, intsize);
126 
127 	if (out_irq->args_count != intsize)
128 		goto fail;
129 
130 	/* Look for this #address-cells. We have to implement the old linux
131 	 * trick of looking for the parent here as some device-trees rely on it
132 	 */
133 	old = of_node_get(ipar);
134 	do {
135 		tmp = of_get_property(old, "#address-cells", NULL);
136 		tnode = of_get_parent(old);
137 		of_node_put(old);
138 		old = tnode;
139 	} while (old && tmp == NULL);
140 	of_node_put(old);
141 	old = NULL;
142 	addrsize = (tmp == NULL) ? 2 : be32_to_cpu(*tmp);
143 
144 	pr_debug(" -> addrsize=%d\n", addrsize);
145 
146 	/* Range check so that the temporary buffer doesn't overflow */
147 	if (WARN_ON(addrsize + intsize > MAX_PHANDLE_ARGS)) {
148 		rc = -EFAULT;
149 		goto fail;
150 	}
151 
152 	/* Precalculate the match array - this simplifies match loop */
153 	for (i = 0; i < addrsize; i++)
154 		initial_match_array[i] = addr ? addr[i] : 0;
155 	for (i = 0; i < intsize; i++)
156 		initial_match_array[addrsize + i] = cpu_to_be32(out_irq->args[i]);
157 
158 	/* Now start the actual "proper" walk of the interrupt tree */
159 	while (ipar != NULL) {
160 		/* Now check if cursor is an interrupt-controller and if it is
161 		 * then we are done
162 		 */
163 		if (of_property_read_bool(ipar, "interrupt-controller")) {
164 			pr_debug(" -> got it !\n");
165 			return 0;
166 		}
167 
168 		/*
169 		 * interrupt-map parsing does not work without a reg
170 		 * property when #address-cells != 0
171 		 */
172 		if (addrsize && !addr) {
173 			pr_debug(" -> no reg passed in when needed !\n");
174 			goto fail;
175 		}
176 
177 		/* Now look for an interrupt-map */
178 		imap = of_get_property(ipar, "interrupt-map", &imaplen);
179 		/* No interrupt map, check for an interrupt parent */
180 		if (imap == NULL) {
181 			pr_debug(" -> no map, getting parent\n");
182 			newpar = of_irq_find_parent(ipar);
183 			goto skiplevel;
184 		}
185 		imaplen /= sizeof(u32);
186 
187 		/* Look for a mask */
188 		imask = of_get_property(ipar, "interrupt-map-mask", NULL);
189 		if (!imask)
190 			imask = dummy_imask;
191 
192 		/* Parse interrupt-map */
193 		match = 0;
194 		while (imaplen > (addrsize + intsize + 1) && !match) {
195 			/* Compare specifiers */
196 			match = 1;
197 			for (i = 0; i < (addrsize + intsize); i++, imaplen--)
198 				match &= !((match_array[i] ^ *imap++) & imask[i]);
199 
200 			pr_debug(" -> match=%d (imaplen=%d)\n", match, imaplen);
201 
202 			/* Get the interrupt parent */
203 			if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
204 				newpar = of_node_get(of_irq_dflt_pic);
205 			else
206 				newpar = of_find_node_by_phandle(be32_to_cpup(imap));
207 			imap++;
208 			--imaplen;
209 
210 			/* Check if not found */
211 			if (newpar == NULL) {
212 				pr_debug(" -> imap parent not found !\n");
213 				goto fail;
214 			}
215 
216 			if (!of_device_is_available(newpar))
217 				match = 0;
218 
219 			/* Get #interrupt-cells and #address-cells of new
220 			 * parent
221 			 */
222 			if (of_property_read_u32(newpar, "#interrupt-cells",
223 						 &newintsize)) {
224 				pr_debug(" -> parent lacks #interrupt-cells!\n");
225 				goto fail;
226 			}
227 			if (of_property_read_u32(newpar, "#address-cells",
228 						 &newaddrsize))
229 				newaddrsize = 0;
230 
231 			pr_debug(" -> newintsize=%d, newaddrsize=%d\n",
232 			    newintsize, newaddrsize);
233 
234 			/* Check for malformed properties */
235 			if (WARN_ON(newaddrsize + newintsize > MAX_PHANDLE_ARGS)
236 			    || (imaplen < (newaddrsize + newintsize))) {
237 				rc = -EFAULT;
238 				goto fail;
239 			}
240 
241 			imap += newaddrsize + newintsize;
242 			imaplen -= newaddrsize + newintsize;
243 
244 			pr_debug(" -> imaplen=%d\n", imaplen);
245 		}
246 		if (!match)
247 			goto fail;
248 
249 		/*
250 		 * Successfully parsed an interrrupt-map translation; copy new
251 		 * interrupt specifier into the out_irq structure
252 		 */
253 		match_array = imap - newaddrsize - newintsize;
254 		for (i = 0; i < newintsize; i++)
255 			out_irq->args[i] = be32_to_cpup(imap - newintsize + i);
256 		out_irq->args_count = intsize = newintsize;
257 		addrsize = newaddrsize;
258 
259 	skiplevel:
260 		/* Iterate again with new parent */
261 		out_irq->np = newpar;
262 		pr_debug(" -> new parent: %pOF\n", newpar);
263 		of_node_put(ipar);
264 		ipar = newpar;
265 		newpar = NULL;
266 	}
267 	rc = -ENOENT; /* No interrupt-map found */
268 
269  fail:
270 	of_node_put(ipar);
271 	of_node_put(newpar);
272 
273 	return rc;
274 }
275 EXPORT_SYMBOL_GPL(of_irq_parse_raw);
276 
277 /**
278  * of_irq_parse_one - Resolve an interrupt for a device
279  * @device: the device whose interrupt is to be resolved
280  * @index: index of the interrupt to resolve
281  * @out_irq: structure of_irq filled by this function
282  *
283  * This function resolves an interrupt for a node by walking the interrupt tree,
284  * finding which interrupt controller node it is attached to, and returning the
285  * interrupt specifier that can be used to retrieve a Linux IRQ number.
286  */
of_irq_parse_one(struct device_node * device,int index,struct of_phandle_args * out_irq)287 int of_irq_parse_one(struct device_node *device, int index, struct of_phandle_args *out_irq)
288 {
289 	struct device_node *p;
290 	const __be32 *addr;
291 	u32 intsize;
292 	int i, res;
293 
294 	pr_debug("of_irq_parse_one: dev=%pOF, index=%d\n", device, index);
295 
296 	/* OldWorld mac stuff is "special", handle out of line */
297 	if (of_irq_workarounds & OF_IMAP_OLDWORLD_MAC)
298 		return of_irq_parse_oldworld(device, index, out_irq);
299 
300 	/* Get the reg property (if any) */
301 	addr = of_get_property(device, "reg", NULL);
302 
303 	/* Try the new-style interrupts-extended first */
304 	res = of_parse_phandle_with_args(device, "interrupts-extended",
305 					"#interrupt-cells", index, out_irq);
306 	if (!res)
307 		return of_irq_parse_raw(addr, out_irq);
308 
309 	/* Look for the interrupt parent. */
310 	p = of_irq_find_parent(device);
311 	if (p == NULL)
312 		return -EINVAL;
313 
314 	/* Get size of interrupt specifier */
315 	if (of_property_read_u32(p, "#interrupt-cells", &intsize)) {
316 		res = -EINVAL;
317 		goto out;
318 	}
319 
320 	pr_debug(" parent=%pOF, intsize=%d\n", p, intsize);
321 
322 	/* Copy intspec into irq structure */
323 	out_irq->np = p;
324 	out_irq->args_count = intsize;
325 	for (i = 0; i < intsize; i++) {
326 		res = of_property_read_u32_index(device, "interrupts",
327 						 (index * intsize) + i,
328 						 out_irq->args + i);
329 		if (res)
330 			goto out;
331 	}
332 
333 	pr_debug(" intspec=%d\n", *out_irq->args);
334 
335 
336 	/* Check if there are any interrupt-map translations to process */
337 	res = of_irq_parse_raw(addr, out_irq);
338  out:
339 	of_node_put(p);
340 	return res;
341 }
342 EXPORT_SYMBOL_GPL(of_irq_parse_one);
343 
344 /**
345  * of_irq_to_resource - Decode a node's IRQ and return it as a resource
346  * @dev: pointer to device tree node
347  * @index: zero-based index of the irq
348  * @r: pointer to resource structure to return result into.
349  */
of_irq_to_resource(struct device_node * dev,int index,struct resource * r)350 int of_irq_to_resource(struct device_node *dev, int index, struct resource *r)
351 {
352 	int irq = of_irq_get(dev, index);
353 
354 	if (irq < 0)
355 		return irq;
356 
357 	/* Only dereference the resource if both the
358 	 * resource and the irq are valid. */
359 	if (r && irq) {
360 		const char *name = NULL;
361 
362 		memset(r, 0, sizeof(*r));
363 		/*
364 		 * Get optional "interrupt-names" property to add a name
365 		 * to the resource.
366 		 */
367 		of_property_read_string_index(dev, "interrupt-names", index,
368 					      &name);
369 
370 		r->start = r->end = irq;
371 		r->flags = IORESOURCE_IRQ | irqd_get_trigger_type(irq_get_irq_data(irq));
372 		r->name = name ? name : of_node_full_name(dev);
373 	}
374 
375 	return irq;
376 }
377 EXPORT_SYMBOL_GPL(of_irq_to_resource);
378 
379 /**
380  * of_irq_get - Decode a node's IRQ and return it as a Linux IRQ number
381  * @dev: pointer to device tree node
382  * @index: zero-based index of the IRQ
383  *
384  * Returns Linux IRQ number on success, or 0 on the IRQ mapping failure, or
385  * -EPROBE_DEFER if the IRQ domain is not yet created, or error code in case
386  * of any other failure.
387  */
of_irq_get(struct device_node * dev,int index)388 int of_irq_get(struct device_node *dev, int index)
389 {
390 	int rc;
391 	struct of_phandle_args oirq;
392 	struct irq_domain *domain;
393 
394 	rc = of_irq_parse_one(dev, index, &oirq);
395 	if (rc)
396 		return rc;
397 
398 	domain = irq_find_host(oirq.np);
399 	if (!domain)
400 		return -EPROBE_DEFER;
401 
402 	return irq_create_of_mapping(&oirq);
403 }
404 EXPORT_SYMBOL_GPL(of_irq_get);
405 
406 /**
407  * of_irq_get_byname - Decode a node's IRQ and return it as a Linux IRQ number
408  * @dev: pointer to device tree node
409  * @name: IRQ name
410  *
411  * Returns Linux IRQ number on success, or 0 on the IRQ mapping failure, or
412  * -EPROBE_DEFER if the IRQ domain is not yet created, or error code in case
413  * of any other failure.
414  */
of_irq_get_byname(struct device_node * dev,const char * name)415 int of_irq_get_byname(struct device_node *dev, const char *name)
416 {
417 	int index;
418 
419 	if (unlikely(!name))
420 		return -EINVAL;
421 
422 	index = of_property_match_string(dev, "interrupt-names", name);
423 	if (index < 0)
424 		return index;
425 
426 	return of_irq_get(dev, index);
427 }
428 EXPORT_SYMBOL_GPL(of_irq_get_byname);
429 
430 /**
431  * of_irq_count - Count the number of IRQs a node uses
432  * @dev: pointer to device tree node
433  */
of_irq_count(struct device_node * dev)434 int of_irq_count(struct device_node *dev)
435 {
436 	struct of_phandle_args irq;
437 	int nr = 0;
438 
439 	while (of_irq_parse_one(dev, nr, &irq) == 0)
440 		nr++;
441 
442 	return nr;
443 }
444 
445 /**
446  * of_irq_to_resource_table - Fill in resource table with node's IRQ info
447  * @dev: pointer to device tree node
448  * @res: array of resources to fill in
449  * @nr_irqs: the number of IRQs (and upper bound for num of @res elements)
450  *
451  * Returns the size of the filled in table (up to @nr_irqs).
452  */
of_irq_to_resource_table(struct device_node * dev,struct resource * res,int nr_irqs)453 int of_irq_to_resource_table(struct device_node *dev, struct resource *res,
454 		int nr_irqs)
455 {
456 	int i;
457 
458 	for (i = 0; i < nr_irqs; i++, res++)
459 		if (of_irq_to_resource(dev, i, res) <= 0)
460 			break;
461 
462 	return i;
463 }
464 EXPORT_SYMBOL_GPL(of_irq_to_resource_table);
465 
466 struct of_intc_desc {
467 	struct list_head	list;
468 	of_irq_init_cb_t	irq_init_cb;
469 	struct device_node	*dev;
470 	struct device_node	*interrupt_parent;
471 };
472 
473 /**
474  * of_irq_init - Scan and init matching interrupt controllers in DT
475  * @matches: 0 terminated array of nodes to match and init function to call
476  *
477  * This function scans the device tree for matching interrupt controller nodes,
478  * and calls their initialization functions in order with parents first.
479  */
of_irq_init(const struct of_device_id * matches)480 void __init of_irq_init(const struct of_device_id *matches)
481 {
482 	const struct of_device_id *match;
483 	struct device_node *np, *parent = NULL;
484 	struct of_intc_desc *desc, *temp_desc;
485 	struct list_head intc_desc_list, intc_parent_list;
486 
487 	INIT_LIST_HEAD(&intc_desc_list);
488 	INIT_LIST_HEAD(&intc_parent_list);
489 
490 	for_each_matching_node_and_match(np, matches, &match) {
491 		if (!of_property_read_bool(np, "interrupt-controller") ||
492 				!of_device_is_available(np))
493 			continue;
494 
495 		if (WARN(!match->data, "of_irq_init: no init function for %s\n",
496 			 match->compatible))
497 			continue;
498 
499 		/*
500 		 * Here, we allocate and populate an of_intc_desc with the node
501 		 * pointer, interrupt-parent device_node etc.
502 		 */
503 		desc = kzalloc(sizeof(*desc), GFP_KERNEL);
504 		if (WARN_ON(!desc)) {
505 			of_node_put(np);
506 			goto err;
507 		}
508 
509 		desc->irq_init_cb = match->data;
510 		desc->dev = of_node_get(np);
511 		desc->interrupt_parent = of_irq_find_parent(np);
512 		if (desc->interrupt_parent == np)
513 			desc->interrupt_parent = NULL;
514 		list_add_tail(&desc->list, &intc_desc_list);
515 	}
516 
517 	/*
518 	 * The root irq controller is the one without an interrupt-parent.
519 	 * That one goes first, followed by the controllers that reference it,
520 	 * followed by the ones that reference the 2nd level controllers, etc.
521 	 */
522 	while (!list_empty(&intc_desc_list)) {
523 		/*
524 		 * Process all controllers with the current 'parent'.
525 		 * First pass will be looking for NULL as the parent.
526 		 * The assumption is that NULL parent means a root controller.
527 		 */
528 		list_for_each_entry_safe(desc, temp_desc, &intc_desc_list, list) {
529 			int ret;
530 
531 			if (desc->interrupt_parent != parent)
532 				continue;
533 
534 			list_del(&desc->list);
535 
536 			of_node_set_flag(desc->dev, OF_POPULATED);
537 
538 			pr_debug("of_irq_init: init %pOF (%p), parent %p\n",
539 				 desc->dev,
540 				 desc->dev, desc->interrupt_parent);
541 			ret = desc->irq_init_cb(desc->dev,
542 						desc->interrupt_parent);
543 			if (ret) {
544 				of_node_clear_flag(desc->dev, OF_POPULATED);
545 				kfree(desc);
546 				continue;
547 			}
548 
549 			/*
550 			 * This one is now set up; add it to the parent list so
551 			 * its children can get processed in a subsequent pass.
552 			 */
553 			list_add_tail(&desc->list, &intc_parent_list);
554 		}
555 
556 		/* Get the next pending parent that might have children */
557 		desc = list_first_entry_or_null(&intc_parent_list,
558 						typeof(*desc), list);
559 		if (!desc) {
560 			pr_err("of_irq_init: children remain, but no parents\n");
561 			break;
562 		}
563 		list_del(&desc->list);
564 		parent = desc->dev;
565 		kfree(desc);
566 	}
567 
568 	list_for_each_entry_safe(desc, temp_desc, &intc_parent_list, list) {
569 		list_del(&desc->list);
570 		kfree(desc);
571 	}
572 err:
573 	list_for_each_entry_safe(desc, temp_desc, &intc_desc_list, list) {
574 		list_del(&desc->list);
575 		of_node_put(desc->dev);
576 		kfree(desc);
577 	}
578 }
579 
__of_msi_map_rid(struct device * dev,struct device_node ** np,u32 rid_in)580 static u32 __of_msi_map_rid(struct device *dev, struct device_node **np,
581 			    u32 rid_in)
582 {
583 	struct device *parent_dev;
584 	u32 rid_out = rid_in;
585 
586 	/*
587 	 * Walk up the device parent links looking for one with a
588 	 * "msi-map" property.
589 	 */
590 	for (parent_dev = dev; parent_dev; parent_dev = parent_dev->parent)
591 		if (!of_pci_map_rid(parent_dev->of_node, rid_in, "msi-map",
592 				    "msi-map-mask", np, &rid_out))
593 			break;
594 	return rid_out;
595 }
596 
597 /**
598  * of_msi_map_rid - Map a MSI requester ID for a device.
599  * @dev: device for which the mapping is to be done.
600  * @msi_np: device node of the expected msi controller.
601  * @rid_in: unmapped MSI requester ID for the device.
602  *
603  * Walk up the device hierarchy looking for devices with a "msi-map"
604  * property.  If found, apply the mapping to @rid_in.
605  *
606  * Returns the mapped MSI requester ID.
607  */
of_msi_map_rid(struct device * dev,struct device_node * msi_np,u32 rid_in)608 u32 of_msi_map_rid(struct device *dev, struct device_node *msi_np, u32 rid_in)
609 {
610 	return __of_msi_map_rid(dev, &msi_np, rid_in);
611 }
612 
613 /**
614  * of_msi_map_get_device_domain - Use msi-map to find the relevant MSI domain
615  * @dev: device for which the mapping is to be done.
616  * @rid: Requester ID for the device.
617  *
618  * Walk up the device hierarchy looking for devices with a "msi-map"
619  * property.
620  *
621  * Returns: the MSI domain for this device (or NULL on failure)
622  */
of_msi_map_get_device_domain(struct device * dev,u32 rid)623 struct irq_domain *of_msi_map_get_device_domain(struct device *dev, u32 rid)
624 {
625 	struct device_node *np = NULL;
626 
627 	__of_msi_map_rid(dev, &np, rid);
628 	return irq_find_matching_host(np, DOMAIN_BUS_PCI_MSI);
629 }
630 
631 /**
632  * of_msi_get_domain - Use msi-parent to find the relevant MSI domain
633  * @dev: device for which the domain is requested
634  * @np: device node for @dev
635  * @token: bus type for this domain
636  *
637  * Parse the msi-parent property (both the simple and the complex
638  * versions), and returns the corresponding MSI domain.
639  *
640  * Returns: the MSI domain for this device (or NULL on failure).
641  */
of_msi_get_domain(struct device * dev,struct device_node * np,enum irq_domain_bus_token token)642 struct irq_domain *of_msi_get_domain(struct device *dev,
643 				     struct device_node *np,
644 				     enum irq_domain_bus_token token)
645 {
646 	struct device_node *msi_np;
647 	struct irq_domain *d;
648 
649 	/* Check for a single msi-parent property */
650 	msi_np = of_parse_phandle(np, "msi-parent", 0);
651 	if (msi_np && !of_property_read_bool(msi_np, "#msi-cells")) {
652 		d = irq_find_matching_host(msi_np, token);
653 		if (!d)
654 			of_node_put(msi_np);
655 		return d;
656 	}
657 
658 	if (token == DOMAIN_BUS_PLATFORM_MSI) {
659 		/* Check for the complex msi-parent version */
660 		struct of_phandle_args args;
661 		int index = 0;
662 
663 		while (!of_parse_phandle_with_args(np, "msi-parent",
664 						   "#msi-cells",
665 						   index, &args)) {
666 			d = irq_find_matching_host(args.np, token);
667 			if (d)
668 				return d;
669 
670 			of_node_put(args.np);
671 			index++;
672 		}
673 	}
674 
675 	return NULL;
676 }
677 
678 /**
679  * of_msi_configure - Set the msi_domain field of a device
680  * @dev: device structure to associate with an MSI irq domain
681  * @np: device node for that device
682  */
of_msi_configure(struct device * dev,struct device_node * np)683 void of_msi_configure(struct device *dev, struct device_node *np)
684 {
685 	dev_set_msi_domain(dev,
686 			   of_msi_get_domain(dev, np, DOMAIN_BUS_PLATFORM_MSI));
687 }
688 EXPORT_SYMBOL_GPL(of_msi_configure);
689