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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/string.h>
26 #include <linux/slab.h>
27 
28 #include "of_private.h"
29 
30 /**
31  * irq_of_parse_and_map - Parse and map an interrupt into linux virq space
32  * @dev: Device node of the device whose interrupt is to be mapped
33  * @index: Index of the interrupt to map
34  *
35  * This function is a wrapper that chains of_irq_parse_one() and
36  * irq_create_of_mapping() to make things easier to callers
37  */
irq_of_parse_and_map(struct device_node * dev,int index)38 unsigned int irq_of_parse_and_map(struct device_node *dev, int index)
39 {
40 	struct of_phandle_args oirq;
41 
42 	if (of_irq_parse_one(dev, index, &oirq))
43 		return 0;
44 
45 	return irq_create_of_mapping(&oirq);
46 }
47 EXPORT_SYMBOL_GPL(irq_of_parse_and_map);
48 
49 /**
50  * of_irq_find_parent - Given a device node, find its interrupt parent node
51  * @child: pointer to device node
52  *
53  * Return: A pointer to the interrupt parent node, or NULL if the interrupt
54  * parent could not be determined.
55  */
of_irq_find_parent(struct device_node * child)56 struct device_node *of_irq_find_parent(struct device_node *child)
57 {
58 	struct device_node *p;
59 	phandle parent;
60 
61 	if (!of_node_get(child))
62 		return NULL;
63 
64 	do {
65 		if (of_property_read_u32(child, "interrupt-parent", &parent)) {
66 			p = of_get_parent(child);
67 		} else	{
68 			if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
69 				p = of_node_get(of_irq_dflt_pic);
70 			else
71 				p = of_find_node_by_phandle(parent);
72 		}
73 		of_node_put(child);
74 		child = p;
75 	} while (p && of_get_property(p, "#interrupt-cells", NULL) == NULL);
76 
77 	return p;
78 }
79 EXPORT_SYMBOL_GPL(of_irq_find_parent);
80 
81 /*
82  * These interrupt controllers abuse interrupt-map for unspeakable
83  * reasons and rely on the core code to *ignore* it (the drivers do
84  * their own parsing of the property). The PAsemi entry covers a
85  * non-sensical interrupt-map that is better left ignored.
86  *
87  * If you think of adding to the list for something *new*, think
88  * again. There is a high chance that you will be sent back to the
89  * drawing board.
90  */
91 static const char * const of_irq_imap_abusers[] = {
92 	"CBEA,platform-spider-pic",
93 	"sti,platform-spider-pic",
94 	"realtek,rtl-intc",
95 	"fsl,ls1021a-extirq",
96 	"fsl,ls1043a-extirq",
97 	"fsl,ls1088a-extirq",
98 	"renesas,rza1-irqc",
99 	"pasemi,rootbus",
100 	NULL,
101 };
102 
of_irq_parse_imap_parent(const __be32 * imap,int len,struct of_phandle_args * out_irq)103 const __be32 *of_irq_parse_imap_parent(const __be32 *imap, int len, struct of_phandle_args *out_irq)
104 {
105 	u32 intsize, addrsize;
106 	struct device_node *np;
107 
108 	/* Get the interrupt parent */
109 	if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
110 		np = of_node_get(of_irq_dflt_pic);
111 	else
112 		np = of_find_node_by_phandle(be32_to_cpup(imap));
113 	imap++;
114 
115 	/* Check if not found */
116 	if (!np) {
117 		pr_debug(" -> imap parent not found !\n");
118 		return NULL;
119 	}
120 
121 	/* Get #interrupt-cells and #address-cells of new parent */
122 	if (of_property_read_u32(np, "#interrupt-cells",
123 					&intsize)) {
124 		pr_debug(" -> parent lacks #interrupt-cells!\n");
125 		of_node_put(np);
126 		return NULL;
127 	}
128 	if (of_property_read_u32(np, "#address-cells",
129 					&addrsize))
130 		addrsize = 0;
131 
132 	pr_debug(" -> intsize=%d, addrsize=%d\n",
133 		intsize, addrsize);
134 
135 	/* Check for malformed properties */
136 	if (WARN_ON(addrsize + intsize > MAX_PHANDLE_ARGS)
137 		|| (len < (addrsize + intsize))) {
138 		of_node_put(np);
139 		return NULL;
140 	}
141 
142 	pr_debug(" -> imaplen=%d\n", len);
143 
144 	imap += addrsize + intsize;
145 
146 	out_irq->np = np;
147 	for (int i = 0; i < intsize; i++)
148 		out_irq->args[i] = be32_to_cpup(imap - intsize + i);
149 	out_irq->args_count = intsize;
150 
151 	return imap;
152 }
153 
154 /**
155  * of_irq_parse_raw - Low level interrupt tree parsing
156  * @addr:	address specifier (start of "reg" property of the device) in be32 format
157  * @out_irq:	structure of_phandle_args updated by this function
158  *
159  * This function is a low-level interrupt tree walking function. It
160  * can be used to do a partial walk with synthetized reg and interrupts
161  * properties, for example when resolving PCI interrupts when no device
162  * node exist for the parent. It takes an interrupt specifier structure as
163  * input, walks the tree looking for any interrupt-map properties, translates
164  * the specifier for each map, and then returns the translated map.
165  *
166  * Return: 0 on success and a negative number on error
167  */
of_irq_parse_raw(const __be32 * addr,struct of_phandle_args * out_irq)168 int of_irq_parse_raw(const __be32 *addr, struct of_phandle_args *out_irq)
169 {
170 	struct device_node *ipar, *tnode, *old = NULL;
171 	__be32 initial_match_array[MAX_PHANDLE_ARGS];
172 	const __be32 *match_array = initial_match_array;
173 	const __be32 *tmp, dummy_imask[] = { [0 ... MAX_PHANDLE_ARGS] = cpu_to_be32(~0) };
174 	u32 intsize = 1, addrsize;
175 	int i, rc = -EINVAL;
176 
177 #ifdef DEBUG
178 	of_print_phandle_args("of_irq_parse_raw: ", out_irq);
179 #endif
180 
181 	ipar = of_node_get(out_irq->np);
182 
183 	/* First get the #interrupt-cells property of the current cursor
184 	 * that tells us how to interpret the passed-in intspec. If there
185 	 * is none, we are nice and just walk up the tree
186 	 */
187 	do {
188 		if (!of_property_read_u32(ipar, "#interrupt-cells", &intsize))
189 			break;
190 		tnode = ipar;
191 		ipar = of_irq_find_parent(ipar);
192 		of_node_put(tnode);
193 	} while (ipar);
194 	if (ipar == NULL) {
195 		pr_debug(" -> no parent found !\n");
196 		goto fail;
197 	}
198 
199 	pr_debug("of_irq_parse_raw: ipar=%pOF, size=%d\n", ipar, intsize);
200 
201 	if (out_irq->args_count != intsize)
202 		goto fail;
203 
204 	/* Look for this #address-cells. We have to implement the old linux
205 	 * trick of looking for the parent here as some device-trees rely on it
206 	 */
207 	old = of_node_get(ipar);
208 	do {
209 		tmp = of_get_property(old, "#address-cells", NULL);
210 		tnode = of_get_parent(old);
211 		of_node_put(old);
212 		old = tnode;
213 	} while (old && tmp == NULL);
214 	of_node_put(old);
215 	old = NULL;
216 	addrsize = (tmp == NULL) ? 2 : be32_to_cpu(*tmp);
217 
218 	pr_debug(" -> addrsize=%d\n", addrsize);
219 
220 	/* Range check so that the temporary buffer doesn't overflow */
221 	if (WARN_ON(addrsize + intsize > MAX_PHANDLE_ARGS)) {
222 		rc = -EFAULT;
223 		goto fail;
224 	}
225 
226 	/* Precalculate the match array - this simplifies match loop */
227 	for (i = 0; i < addrsize; i++)
228 		initial_match_array[i] = addr ? addr[i] : 0;
229 	for (i = 0; i < intsize; i++)
230 		initial_match_array[addrsize + i] = cpu_to_be32(out_irq->args[i]);
231 
232 	/* Now start the actual "proper" walk of the interrupt tree */
233 	while (ipar != NULL) {
234 		int imaplen, match;
235 		const __be32 *imap, *oldimap, *imask;
236 		struct device_node *newpar;
237 		/*
238 		 * Now check if cursor is an interrupt-controller and
239 		 * if it is then we are done, unless there is an
240 		 * interrupt-map which takes precedence except on one
241 		 * of these broken platforms that want to parse
242 		 * interrupt-map themselves for $reason.
243 		 */
244 		bool intc = of_property_read_bool(ipar, "interrupt-controller");
245 
246 		imap = of_get_property(ipar, "interrupt-map", &imaplen);
247 		if (intc &&
248 		    (!imap || of_device_compatible_match(ipar, of_irq_imap_abusers))) {
249 			pr_debug(" -> got it !\n");
250 			return 0;
251 		}
252 
253 		/*
254 		 * interrupt-map parsing does not work without a reg
255 		 * property when #address-cells != 0
256 		 */
257 		if (addrsize && !addr) {
258 			pr_debug(" -> no reg passed in when needed !\n");
259 			goto fail;
260 		}
261 
262 		/* No interrupt map, check for an interrupt parent */
263 		if (imap == NULL) {
264 			pr_debug(" -> no map, getting parent\n");
265 			newpar = of_irq_find_parent(ipar);
266 			goto skiplevel;
267 		}
268 		imaplen /= sizeof(u32);
269 
270 		/* Look for a mask */
271 		imask = of_get_property(ipar, "interrupt-map-mask", NULL);
272 		if (!imask)
273 			imask = dummy_imask;
274 
275 		/* Parse interrupt-map */
276 		match = 0;
277 		while (imaplen > (addrsize + intsize + 1)) {
278 			/* Compare specifiers */
279 			match = 1;
280 			for (i = 0; i < (addrsize + intsize); i++, imaplen--)
281 				match &= !((match_array[i] ^ *imap++) & imask[i]);
282 
283 			pr_debug(" -> match=%d (imaplen=%d)\n", match, imaplen);
284 
285 			oldimap = imap;
286 			imap = of_irq_parse_imap_parent(oldimap, imaplen, out_irq);
287 			if (!imap)
288 				goto fail;
289 
290 			match &= of_device_is_available(out_irq->np);
291 			if (match)
292 				break;
293 
294 			of_node_put(out_irq->np);
295 			imaplen -= imap - oldimap;
296 			pr_debug(" -> imaplen=%d\n", imaplen);
297 		}
298 		if (!match)
299 			goto fail;
300 
301 		/*
302 		 * Successfully parsed an interrupt-map translation; copy new
303 		 * interrupt specifier into the out_irq structure
304 		 */
305 		match_array = oldimap + 1;
306 
307 		newpar = out_irq->np;
308 		intsize = out_irq->args_count;
309 		addrsize = (imap - match_array) - intsize;
310 
311 		if (ipar == newpar) {
312 			pr_debug("%pOF interrupt-map entry to self\n", ipar);
313 			return 0;
314 		}
315 
316 	skiplevel:
317 		/* Iterate again with new parent */
318 		pr_debug(" -> new parent: %pOF\n", newpar);
319 		of_node_put(ipar);
320 		ipar = newpar;
321 		newpar = NULL;
322 	}
323 	rc = -ENOENT; /* No interrupt-map found */
324 
325  fail:
326 	of_node_put(ipar);
327 
328 	return rc;
329 }
330 EXPORT_SYMBOL_GPL(of_irq_parse_raw);
331 
332 /**
333  * of_irq_parse_one - Resolve an interrupt for a device
334  * @device: the device whose interrupt is to be resolved
335  * @index: index of the interrupt to resolve
336  * @out_irq: structure of_phandle_args filled by this function
337  *
338  * This function resolves an interrupt for a node by walking the interrupt tree,
339  * finding which interrupt controller node it is attached to, and returning the
340  * interrupt specifier that can be used to retrieve a Linux IRQ number.
341  */
of_irq_parse_one(struct device_node * device,int index,struct of_phandle_args * out_irq)342 int of_irq_parse_one(struct device_node *device, int index, struct of_phandle_args *out_irq)
343 {
344 	struct device_node *p;
345 	const __be32 *addr;
346 	u32 intsize;
347 	int i, res;
348 
349 	pr_debug("of_irq_parse_one: dev=%pOF, index=%d\n", device, index);
350 
351 	/* OldWorld mac stuff is "special", handle out of line */
352 	if (of_irq_workarounds & OF_IMAP_OLDWORLD_MAC)
353 		return of_irq_parse_oldworld(device, index, out_irq);
354 
355 	/* Get the reg property (if any) */
356 	addr = of_get_property(device, "reg", NULL);
357 
358 	/* Try the new-style interrupts-extended first */
359 	res = of_parse_phandle_with_args(device, "interrupts-extended",
360 					"#interrupt-cells", index, out_irq);
361 	if (!res)
362 		return of_irq_parse_raw(addr, out_irq);
363 
364 	/* Look for the interrupt parent. */
365 	p = of_irq_find_parent(device);
366 	if (p == NULL)
367 		return -EINVAL;
368 
369 	/* Get size of interrupt specifier */
370 	if (of_property_read_u32(p, "#interrupt-cells", &intsize)) {
371 		res = -EINVAL;
372 		goto out;
373 	}
374 
375 	pr_debug(" parent=%pOF, intsize=%d\n", p, intsize);
376 
377 	/* Copy intspec into irq structure */
378 	out_irq->np = p;
379 	out_irq->args_count = intsize;
380 	for (i = 0; i < intsize; i++) {
381 		res = of_property_read_u32_index(device, "interrupts",
382 						 (index * intsize) + i,
383 						 out_irq->args + i);
384 		if (res)
385 			goto out;
386 	}
387 
388 	pr_debug(" intspec=%d\n", *out_irq->args);
389 
390 
391 	/* Check if there are any interrupt-map translations to process */
392 	res = of_irq_parse_raw(addr, out_irq);
393  out:
394 	of_node_put(p);
395 	return res;
396 }
397 EXPORT_SYMBOL_GPL(of_irq_parse_one);
398 
399 /**
400  * of_irq_to_resource - Decode a node's IRQ and return it as a resource
401  * @dev: pointer to device tree node
402  * @index: zero-based index of the irq
403  * @r: pointer to resource structure to return result into.
404  */
of_irq_to_resource(struct device_node * dev,int index,struct resource * r)405 int of_irq_to_resource(struct device_node *dev, int index, struct resource *r)
406 {
407 	int irq = of_irq_get(dev, index);
408 
409 	if (irq < 0)
410 		return irq;
411 
412 	/* Only dereference the resource if both the
413 	 * resource and the irq are valid. */
414 	if (r && irq) {
415 		const char *name = NULL;
416 
417 		memset(r, 0, sizeof(*r));
418 		/*
419 		 * Get optional "interrupt-names" property to add a name
420 		 * to the resource.
421 		 */
422 		of_property_read_string_index(dev, "interrupt-names", index,
423 					      &name);
424 
425 		r->start = r->end = irq;
426 		r->flags = IORESOURCE_IRQ | irqd_get_trigger_type(irq_get_irq_data(irq));
427 		r->name = name ? name : of_node_full_name(dev);
428 	}
429 
430 	return irq;
431 }
432 EXPORT_SYMBOL_GPL(of_irq_to_resource);
433 
434 /**
435  * of_irq_get - Decode a node's IRQ and return it as a Linux IRQ number
436  * @dev: pointer to device tree node
437  * @index: zero-based index of the IRQ
438  *
439  * Return: Linux IRQ number on success, or 0 on the IRQ mapping failure, or
440  * -EPROBE_DEFER if the IRQ domain is not yet created, or error code in case
441  * of any other failure.
442  */
of_irq_get(struct device_node * dev,int index)443 int of_irq_get(struct device_node *dev, int index)
444 {
445 	int rc;
446 	struct of_phandle_args oirq;
447 	struct irq_domain *domain;
448 
449 	rc = of_irq_parse_one(dev, index, &oirq);
450 	if (rc)
451 		return rc;
452 
453 	domain = irq_find_host(oirq.np);
454 	if (!domain) {
455 		rc = -EPROBE_DEFER;
456 		goto out;
457 	}
458 
459 	rc = irq_create_of_mapping(&oirq);
460 out:
461 	of_node_put(oirq.np);
462 
463 	return rc;
464 }
465 EXPORT_SYMBOL_GPL(of_irq_get);
466 
467 /**
468  * of_irq_get_byname - Decode a node's IRQ and return it as a Linux IRQ number
469  * @dev: pointer to device tree node
470  * @name: IRQ name
471  *
472  * Return: Linux IRQ number on success, or 0 on the IRQ mapping failure, or
473  * -EPROBE_DEFER if the IRQ domain is not yet created, or error code in case
474  * of any other failure.
475  */
of_irq_get_byname(struct device_node * dev,const char * name)476 int of_irq_get_byname(struct device_node *dev, const char *name)
477 {
478 	int index;
479 
480 	if (unlikely(!name))
481 		return -EINVAL;
482 
483 	index = of_property_match_string(dev, "interrupt-names", name);
484 	if (index < 0)
485 		return index;
486 
487 	return of_irq_get(dev, index);
488 }
489 EXPORT_SYMBOL_GPL(of_irq_get_byname);
490 
491 /**
492  * of_irq_count - Count the number of IRQs a node uses
493  * @dev: pointer to device tree node
494  */
of_irq_count(struct device_node * dev)495 int of_irq_count(struct device_node *dev)
496 {
497 	struct of_phandle_args irq;
498 	int nr = 0;
499 
500 	while (of_irq_parse_one(dev, nr, &irq) == 0)
501 		nr++;
502 
503 	return nr;
504 }
505 
506 /**
507  * of_irq_to_resource_table - Fill in resource table with node's IRQ info
508  * @dev: pointer to device tree node
509  * @res: array of resources to fill in
510  * @nr_irqs: the number of IRQs (and upper bound for num of @res elements)
511  *
512  * Return: The size of the filled in table (up to @nr_irqs).
513  */
of_irq_to_resource_table(struct device_node * dev,struct resource * res,int nr_irqs)514 int of_irq_to_resource_table(struct device_node *dev, struct resource *res,
515 		int nr_irqs)
516 {
517 	int i;
518 
519 	for (i = 0; i < nr_irqs; i++, res++)
520 		if (of_irq_to_resource(dev, i, res) <= 0)
521 			break;
522 
523 	return i;
524 }
525 EXPORT_SYMBOL_GPL(of_irq_to_resource_table);
526 
527 struct of_intc_desc {
528 	struct list_head	list;
529 	of_irq_init_cb_t	irq_init_cb;
530 	struct device_node	*dev;
531 	struct device_node	*interrupt_parent;
532 };
533 
534 /**
535  * of_irq_init - Scan and init matching interrupt controllers in DT
536  * @matches: 0 terminated array of nodes to match and init function to call
537  *
538  * This function scans the device tree for matching interrupt controller nodes,
539  * and calls their initialization functions in order with parents first.
540  */
of_irq_init(const struct of_device_id * matches)541 void __init of_irq_init(const struct of_device_id *matches)
542 {
543 	const struct of_device_id *match;
544 	struct device_node *np, *parent = NULL;
545 	struct of_intc_desc *desc, *temp_desc;
546 	struct list_head intc_desc_list, intc_parent_list;
547 
548 	INIT_LIST_HEAD(&intc_desc_list);
549 	INIT_LIST_HEAD(&intc_parent_list);
550 
551 	for_each_matching_node_and_match(np, matches, &match) {
552 		if (!of_property_read_bool(np, "interrupt-controller") ||
553 				!of_device_is_available(np))
554 			continue;
555 
556 		if (WARN(!match->data, "of_irq_init: no init function for %s\n",
557 			 match->compatible))
558 			continue;
559 
560 		/*
561 		 * Here, we allocate and populate an of_intc_desc with the node
562 		 * pointer, interrupt-parent device_node etc.
563 		 */
564 		desc = kzalloc(sizeof(*desc), GFP_KERNEL);
565 		if (!desc) {
566 			of_node_put(np);
567 			goto err;
568 		}
569 
570 		desc->irq_init_cb = match->data;
571 		desc->dev = of_node_get(np);
572 		/*
573 		 * interrupts-extended can reference multiple parent domains.
574 		 * Arbitrarily pick the first one; assume any other parents
575 		 * are the same distance away from the root irq controller.
576 		 */
577 		desc->interrupt_parent = of_parse_phandle(np, "interrupts-extended", 0);
578 		if (!desc->interrupt_parent)
579 			desc->interrupt_parent = of_irq_find_parent(np);
580 		if (desc->interrupt_parent == np) {
581 			of_node_put(desc->interrupt_parent);
582 			desc->interrupt_parent = NULL;
583 		}
584 		list_add_tail(&desc->list, &intc_desc_list);
585 	}
586 
587 	/*
588 	 * The root irq controller is the one without an interrupt-parent.
589 	 * That one goes first, followed by the controllers that reference it,
590 	 * followed by the ones that reference the 2nd level controllers, etc.
591 	 */
592 	while (!list_empty(&intc_desc_list)) {
593 		/*
594 		 * Process all controllers with the current 'parent'.
595 		 * First pass will be looking for NULL as the parent.
596 		 * The assumption is that NULL parent means a root controller.
597 		 */
598 		list_for_each_entry_safe(desc, temp_desc, &intc_desc_list, list) {
599 			int ret;
600 
601 			if (desc->interrupt_parent != parent)
602 				continue;
603 
604 			list_del(&desc->list);
605 
606 			of_node_set_flag(desc->dev, OF_POPULATED);
607 
608 			pr_debug("of_irq_init: init %pOF (%p), parent %p\n",
609 				 desc->dev,
610 				 desc->dev, desc->interrupt_parent);
611 			ret = desc->irq_init_cb(desc->dev,
612 						desc->interrupt_parent);
613 			if (ret) {
614 				pr_err("%s: Failed to init %pOF (%p), parent %p\n",
615 				       __func__, desc->dev, desc->dev,
616 				       desc->interrupt_parent);
617 				of_node_clear_flag(desc->dev, OF_POPULATED);
618 				kfree(desc);
619 				continue;
620 			}
621 
622 			/*
623 			 * This one is now set up; add it to the parent list so
624 			 * its children can get processed in a subsequent pass.
625 			 */
626 			list_add_tail(&desc->list, &intc_parent_list);
627 		}
628 
629 		/* Get the next pending parent that might have children */
630 		desc = list_first_entry_or_null(&intc_parent_list,
631 						typeof(*desc), list);
632 		if (!desc) {
633 			pr_err("of_irq_init: children remain, but no parents\n");
634 			break;
635 		}
636 		list_del(&desc->list);
637 		parent = desc->dev;
638 		kfree(desc);
639 	}
640 
641 	list_for_each_entry_safe(desc, temp_desc, &intc_parent_list, list) {
642 		list_del(&desc->list);
643 		kfree(desc);
644 	}
645 err:
646 	list_for_each_entry_safe(desc, temp_desc, &intc_desc_list, list) {
647 		list_del(&desc->list);
648 		of_node_put(desc->dev);
649 		kfree(desc);
650 	}
651 }
652 
__of_msi_map_id(struct device * dev,struct device_node ** np,u32 id_in)653 static u32 __of_msi_map_id(struct device *dev, struct device_node **np,
654 			    u32 id_in)
655 {
656 	struct device *parent_dev;
657 	u32 id_out = id_in;
658 
659 	/*
660 	 * Walk up the device parent links looking for one with a
661 	 * "msi-map" property.
662 	 */
663 	for (parent_dev = dev; parent_dev; parent_dev = parent_dev->parent)
664 		if (!of_map_id(parent_dev->of_node, id_in, "msi-map",
665 				"msi-map-mask", np, &id_out))
666 			break;
667 	return id_out;
668 }
669 
670 /**
671  * of_msi_map_id - Map a MSI ID for a device.
672  * @dev: device for which the mapping is to be done.
673  * @msi_np: device node of the expected msi controller.
674  * @id_in: unmapped MSI ID for the device.
675  *
676  * Walk up the device hierarchy looking for devices with a "msi-map"
677  * property.  If found, apply the mapping to @id_in.
678  *
679  * Return: The mapped MSI ID.
680  */
of_msi_map_id(struct device * dev,struct device_node * msi_np,u32 id_in)681 u32 of_msi_map_id(struct device *dev, struct device_node *msi_np, u32 id_in)
682 {
683 	return __of_msi_map_id(dev, &msi_np, id_in);
684 }
685 
686 /**
687  * of_msi_map_get_device_domain - Use msi-map to find the relevant MSI domain
688  * @dev: device for which the mapping is to be done.
689  * @id: Device ID.
690  * @bus_token: Bus token
691  *
692  * Walk up the device hierarchy looking for devices with a "msi-map"
693  * property.
694  *
695  * Returns: the MSI domain for this device (or NULL on failure)
696  */
of_msi_map_get_device_domain(struct device * dev,u32 id,u32 bus_token)697 struct irq_domain *of_msi_map_get_device_domain(struct device *dev, u32 id,
698 						u32 bus_token)
699 {
700 	struct device_node *np = NULL;
701 
702 	__of_msi_map_id(dev, &np, id);
703 	return irq_find_matching_host(np, bus_token);
704 }
705 
706 /**
707  * of_msi_get_domain - Use msi-parent to find the relevant MSI domain
708  * @dev: device for which the domain is requested
709  * @np: device node for @dev
710  * @token: bus type for this domain
711  *
712  * Parse the msi-parent property (both the simple and the complex
713  * versions), and returns the corresponding MSI domain.
714  *
715  * Returns: the MSI domain for this device (or NULL on failure).
716  */
of_msi_get_domain(struct device * dev,struct device_node * np,enum irq_domain_bus_token token)717 struct irq_domain *of_msi_get_domain(struct device *dev,
718 				     struct device_node *np,
719 				     enum irq_domain_bus_token token)
720 {
721 	struct device_node *msi_np;
722 	struct irq_domain *d;
723 
724 	/* Check for a single msi-parent property */
725 	msi_np = of_parse_phandle(np, "msi-parent", 0);
726 	if (msi_np && !of_property_read_bool(msi_np, "#msi-cells")) {
727 		d = irq_find_matching_host(msi_np, token);
728 		if (!d)
729 			of_node_put(msi_np);
730 		return d;
731 	}
732 
733 	if (token == DOMAIN_BUS_PLATFORM_MSI) {
734 		/* Check for the complex msi-parent version */
735 		struct of_phandle_args args;
736 		int index = 0;
737 
738 		while (!of_parse_phandle_with_args(np, "msi-parent",
739 						   "#msi-cells",
740 						   index, &args)) {
741 			d = irq_find_matching_host(args.np, token);
742 			if (d)
743 				return d;
744 
745 			of_node_put(args.np);
746 			index++;
747 		}
748 	}
749 
750 	return NULL;
751 }
752 EXPORT_SYMBOL_GPL(of_msi_get_domain);
753 
754 /**
755  * of_msi_configure - Set the msi_domain field of a device
756  * @dev: device structure to associate with an MSI irq domain
757  * @np: device node for that device
758  */
of_msi_configure(struct device * dev,struct device_node * np)759 void of_msi_configure(struct device *dev, struct device_node *np)
760 {
761 	dev_set_msi_domain(dev,
762 			   of_msi_get_domain(dev, np, DOMAIN_BUS_PLATFORM_MSI));
763 }
764 EXPORT_SYMBOL_GPL(of_msi_configure);
765