xref: /linux/drivers/of/irq.c (revision bcde95ce32b666478d6737219caa4f8005a8f201)
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 	len--;
115 
116 	/* Check if not found */
117 	if (!np) {
118 		pr_debug(" -> imap parent not found !\n");
119 		return NULL;
120 	}
121 
122 	/* Get #interrupt-cells and #address-cells of new parent */
123 	if (of_property_read_u32(np, "#interrupt-cells",
124 					&intsize)) {
125 		pr_debug(" -> parent lacks #interrupt-cells!\n");
126 		of_node_put(np);
127 		return NULL;
128 	}
129 	if (of_property_read_u32(np, "#address-cells",
130 					&addrsize))
131 		addrsize = 0;
132 
133 	pr_debug(" -> intsize=%d, addrsize=%d\n",
134 		intsize, addrsize);
135 
136 	/* Check for malformed properties */
137 	if (WARN_ON(addrsize + intsize > MAX_PHANDLE_ARGS)
138 		|| (len < (addrsize + intsize))) {
139 		of_node_put(np);
140 		return NULL;
141 	}
142 
143 	pr_debug(" -> imaplen=%d\n", len);
144 
145 	imap += addrsize + intsize;
146 
147 	out_irq->np = np;
148 	for (int i = 0; i < intsize; i++)
149 		out_irq->args[i] = be32_to_cpup(imap - intsize + i);
150 	out_irq->args_count = intsize;
151 
152 	return imap;
153 }
154 
155 /**
156  * of_irq_parse_raw - Low level interrupt tree parsing
157  * @addr:	address specifier (start of "reg" property of the device) in be32 format
158  * @out_irq:	structure of_phandle_args updated by this function
159  *
160  * This function is a low-level interrupt tree walking function. It
161  * can be used to do a partial walk with synthetized reg and interrupts
162  * properties, for example when resolving PCI interrupts when no device
163  * node exist for the parent. It takes an interrupt specifier structure as
164  * input, walks the tree looking for any interrupt-map properties, translates
165  * the specifier for each map, and then returns the translated map.
166  *
167  * Return: 0 on success and a negative number on error
168  */
of_irq_parse_raw(const __be32 * addr,struct of_phandle_args * out_irq)169 int of_irq_parse_raw(const __be32 *addr, struct of_phandle_args *out_irq)
170 {
171 	struct device_node *ipar, *tnode, *old = NULL;
172 	__be32 initial_match_array[MAX_PHANDLE_ARGS];
173 	const __be32 *match_array = initial_match_array;
174 	const __be32 *tmp, dummy_imask[] = { [0 ... MAX_PHANDLE_ARGS] = cpu_to_be32(~0) };
175 	u32 intsize = 1, addrsize;
176 	int i, rc = -EINVAL;
177 
178 #ifdef DEBUG
179 	of_print_phandle_args("of_irq_parse_raw: ", out_irq);
180 #endif
181 
182 	ipar = of_node_get(out_irq->np);
183 
184 	/* First get the #interrupt-cells property of the current cursor
185 	 * that tells us how to interpret the passed-in intspec. If there
186 	 * is none, we are nice and just walk up the tree
187 	 */
188 	do {
189 		if (!of_property_read_u32(ipar, "#interrupt-cells", &intsize))
190 			break;
191 		tnode = ipar;
192 		ipar = of_irq_find_parent(ipar);
193 		of_node_put(tnode);
194 	} while (ipar);
195 	if (ipar == NULL) {
196 		pr_debug(" -> no parent found !\n");
197 		goto fail;
198 	}
199 
200 	pr_debug("of_irq_parse_raw: ipar=%pOF, size=%d\n", ipar, intsize);
201 
202 	if (out_irq->args_count != intsize)
203 		goto fail;
204 
205 	/* Look for this #address-cells. We have to implement the old linux
206 	 * trick of looking for the parent here as some device-trees rely on it
207 	 */
208 	old = of_node_get(ipar);
209 	do {
210 		tmp = of_get_property(old, "#address-cells", NULL);
211 		tnode = of_get_parent(old);
212 		of_node_put(old);
213 		old = tnode;
214 	} while (old && tmp == NULL);
215 	of_node_put(old);
216 	old = NULL;
217 	addrsize = (tmp == NULL) ? 2 : be32_to_cpu(*tmp);
218 
219 	pr_debug(" -> addrsize=%d\n", addrsize);
220 
221 	/* Range check so that the temporary buffer doesn't overflow */
222 	if (WARN_ON(addrsize + intsize > MAX_PHANDLE_ARGS)) {
223 		rc = -EFAULT;
224 		goto fail;
225 	}
226 
227 	/* Precalculate the match array - this simplifies match loop */
228 	for (i = 0; i < addrsize; i++)
229 		initial_match_array[i] = addr ? addr[i] : 0;
230 	for (i = 0; i < intsize; i++)
231 		initial_match_array[addrsize + i] = cpu_to_be32(out_irq->args[i]);
232 
233 	/* Now start the actual "proper" walk of the interrupt tree */
234 	while (ipar != NULL) {
235 		int imaplen, match;
236 		const __be32 *imap, *oldimap, *imask;
237 		struct device_node *newpar;
238 		/*
239 		 * Now check if cursor is an interrupt-controller and
240 		 * if it is then we are done, unless there is an
241 		 * interrupt-map which takes precedence except on one
242 		 * of these broken platforms that want to parse
243 		 * interrupt-map themselves for $reason.
244 		 */
245 		bool intc = of_property_read_bool(ipar, "interrupt-controller");
246 
247 		imap = of_get_property(ipar, "interrupt-map", &imaplen);
248 		if (intc &&
249 		    (!imap || of_device_compatible_match(ipar, of_irq_imap_abusers))) {
250 			pr_debug(" -> got it !\n");
251 			return 0;
252 		}
253 
254 		/*
255 		 * interrupt-map parsing does not work without a reg
256 		 * property when #address-cells != 0
257 		 */
258 		if (addrsize && !addr) {
259 			pr_debug(" -> no reg passed in when needed !\n");
260 			goto fail;
261 		}
262 
263 		/* No interrupt map, check for an interrupt parent */
264 		if (imap == NULL) {
265 			pr_debug(" -> no map, getting parent\n");
266 			newpar = of_irq_find_parent(ipar);
267 			goto skiplevel;
268 		}
269 		imaplen /= sizeof(u32);
270 
271 		/* Look for a mask */
272 		imask = of_get_property(ipar, "interrupt-map-mask", NULL);
273 		if (!imask)
274 			imask = dummy_imask;
275 
276 		/* Parse interrupt-map */
277 		match = 0;
278 		while (imaplen > (addrsize + intsize + 1)) {
279 			/* Compare specifiers */
280 			match = 1;
281 			for (i = 0; i < (addrsize + intsize); i++, imaplen--)
282 				match &= !((match_array[i] ^ *imap++) & imask[i]);
283 
284 			pr_debug(" -> match=%d (imaplen=%d)\n", match, imaplen);
285 
286 			oldimap = imap;
287 			imap = of_irq_parse_imap_parent(oldimap, imaplen, out_irq);
288 			if (!imap)
289 				goto fail;
290 
291 			match &= of_device_is_available(out_irq->np);
292 			if (match)
293 				break;
294 
295 			of_node_put(out_irq->np);
296 			imaplen -= imap - oldimap;
297 			pr_debug(" -> imaplen=%d\n", imaplen);
298 		}
299 		if (!match)
300 			goto fail;
301 
302 		/*
303 		 * Successfully parsed an interrupt-map translation; copy new
304 		 * interrupt specifier into the out_irq structure
305 		 */
306 		match_array = oldimap + 1;
307 
308 		newpar = out_irq->np;
309 		intsize = out_irq->args_count;
310 		addrsize = (imap - match_array) - intsize;
311 
312 		if (ipar == newpar) {
313 			pr_debug("%pOF interrupt-map entry to self\n", ipar);
314 			return 0;
315 		}
316 
317 	skiplevel:
318 		/* Iterate again with new parent */
319 		pr_debug(" -> new parent: %pOF\n", newpar);
320 		of_node_put(ipar);
321 		ipar = newpar;
322 		newpar = NULL;
323 	}
324 	rc = -ENOENT; /* No interrupt-map found */
325 
326  fail:
327 	of_node_put(ipar);
328 
329 	return rc;
330 }
331 EXPORT_SYMBOL_GPL(of_irq_parse_raw);
332 
333 /**
334  * of_irq_parse_one - Resolve an interrupt for a device
335  * @device: the device whose interrupt is to be resolved
336  * @index: index of the interrupt to resolve
337  * @out_irq: structure of_phandle_args filled by this function
338  *
339  * This function resolves an interrupt for a node by walking the interrupt tree,
340  * finding which interrupt controller node it is attached to, and returning the
341  * interrupt specifier that can be used to retrieve a Linux IRQ number.
342  */
of_irq_parse_one(struct device_node * device,int index,struct of_phandle_args * out_irq)343 int of_irq_parse_one(struct device_node *device, int index, struct of_phandle_args *out_irq)
344 {
345 	struct device_node *p;
346 	const __be32 *addr;
347 	u32 intsize;
348 	int i, res, addr_len;
349 	__be32 addr_buf[3] = { 0 };
350 
351 	pr_debug("of_irq_parse_one: dev=%pOF, index=%d\n", device, index);
352 
353 	/* OldWorld mac stuff is "special", handle out of line */
354 	if (of_irq_workarounds & OF_IMAP_OLDWORLD_MAC)
355 		return of_irq_parse_oldworld(device, index, out_irq);
356 
357 	/* Get the reg property (if any) */
358 	addr_len = 0;
359 	addr = of_get_property(device, "reg", &addr_len);
360 
361 	/* Prevent out-of-bounds read in case of longer interrupt parent address size */
362 	if (addr_len > sizeof(addr_buf))
363 		addr_len = sizeof(addr_buf);
364 	if (addr)
365 		memcpy(addr_buf, addr, addr_len);
366 
367 	/* Try the new-style interrupts-extended first */
368 	res = of_parse_phandle_with_args(device, "interrupts-extended",
369 					"#interrupt-cells", index, out_irq);
370 	if (!res)
371 		return of_irq_parse_raw(addr_buf, out_irq);
372 
373 	/* Look for the interrupt parent. */
374 	p = of_irq_find_parent(device);
375 	if (p == NULL)
376 		return -EINVAL;
377 
378 	/* Get size of interrupt specifier */
379 	if (of_property_read_u32(p, "#interrupt-cells", &intsize)) {
380 		res = -EINVAL;
381 		goto out;
382 	}
383 
384 	pr_debug(" parent=%pOF, intsize=%d\n", p, intsize);
385 
386 	/* Copy intspec into irq structure */
387 	out_irq->np = p;
388 	out_irq->args_count = intsize;
389 	for (i = 0; i < intsize; i++) {
390 		res = of_property_read_u32_index(device, "interrupts",
391 						 (index * intsize) + i,
392 						 out_irq->args + i);
393 		if (res)
394 			goto out;
395 	}
396 
397 	pr_debug(" intspec=%d\n", *out_irq->args);
398 
399 
400 	/* Check if there are any interrupt-map translations to process */
401 	res = of_irq_parse_raw(addr_buf, out_irq);
402  out:
403 	of_node_put(p);
404 	return res;
405 }
406 EXPORT_SYMBOL_GPL(of_irq_parse_one);
407 
408 /**
409  * of_irq_to_resource - Decode a node's IRQ and return it as a resource
410  * @dev: pointer to device tree node
411  * @index: zero-based index of the irq
412  * @r: pointer to resource structure to return result into.
413  */
of_irq_to_resource(struct device_node * dev,int index,struct resource * r)414 int of_irq_to_resource(struct device_node *dev, int index, struct resource *r)
415 {
416 	int irq = of_irq_get(dev, index);
417 
418 	if (irq < 0)
419 		return irq;
420 
421 	/* Only dereference the resource if both the
422 	 * resource and the irq are valid. */
423 	if (r && irq) {
424 		const char *name = NULL;
425 
426 		memset(r, 0, sizeof(*r));
427 		/*
428 		 * Get optional "interrupt-names" property to add a name
429 		 * to the resource.
430 		 */
431 		of_property_read_string_index(dev, "interrupt-names", index,
432 					      &name);
433 
434 		*r = DEFINE_RES_IRQ_NAMED(irq, name ?: of_node_full_name(dev));
435 		r->flags |= irq_get_trigger_type(irq);
436 	}
437 
438 	return irq;
439 }
440 EXPORT_SYMBOL_GPL(of_irq_to_resource);
441 
442 /**
443  * of_irq_get - Decode a node's IRQ and return it as a Linux IRQ number
444  * @dev: pointer to device tree node
445  * @index: zero-based index of the IRQ
446  *
447  * Return: Linux IRQ number on success, or 0 on the IRQ mapping failure, or
448  * -EPROBE_DEFER if the IRQ domain is not yet created, or error code in case
449  * of any other failure.
450  */
of_irq_get(struct device_node * dev,int index)451 int of_irq_get(struct device_node *dev, int index)
452 {
453 	int rc;
454 	struct of_phandle_args oirq;
455 	struct irq_domain *domain;
456 
457 	rc = of_irq_parse_one(dev, index, &oirq);
458 	if (rc)
459 		return rc;
460 
461 	domain = irq_find_host(oirq.np);
462 	if (!domain) {
463 		rc = -EPROBE_DEFER;
464 		goto out;
465 	}
466 
467 	rc = irq_create_of_mapping(&oirq);
468 out:
469 	of_node_put(oirq.np);
470 
471 	return rc;
472 }
473 EXPORT_SYMBOL_GPL(of_irq_get);
474 
475 /**
476  * of_irq_get_byname - Decode a node's IRQ and return it as a Linux IRQ number
477  * @dev: pointer to device tree node
478  * @name: IRQ name
479  *
480  * Return: Linux IRQ number on success, or 0 on the IRQ mapping failure, or
481  * -EPROBE_DEFER if the IRQ domain is not yet created, or error code in case
482  * of any other failure.
483  */
of_irq_get_byname(struct device_node * dev,const char * name)484 int of_irq_get_byname(struct device_node *dev, const char *name)
485 {
486 	int index;
487 
488 	if (unlikely(!name))
489 		return -EINVAL;
490 
491 	index = of_property_match_string(dev, "interrupt-names", name);
492 	if (index < 0)
493 		return index;
494 
495 	return of_irq_get(dev, index);
496 }
497 EXPORT_SYMBOL_GPL(of_irq_get_byname);
498 
499 /**
500  * of_irq_count - Count the number of IRQs a node uses
501  * @dev: pointer to device tree node
502  */
of_irq_count(struct device_node * dev)503 int of_irq_count(struct device_node *dev)
504 {
505 	struct of_phandle_args irq;
506 	int nr = 0;
507 
508 	while (of_irq_parse_one(dev, nr, &irq) == 0)
509 		nr++;
510 
511 	return nr;
512 }
513 
514 /**
515  * of_irq_to_resource_table - Fill in resource table with node's IRQ info
516  * @dev: pointer to device tree node
517  * @res: array of resources to fill in
518  * @nr_irqs: the number of IRQs (and upper bound for num of @res elements)
519  *
520  * Return: The size of the filled in table (up to @nr_irqs).
521  */
of_irq_to_resource_table(struct device_node * dev,struct resource * res,int nr_irqs)522 int of_irq_to_resource_table(struct device_node *dev, struct resource *res,
523 		int nr_irqs)
524 {
525 	int i;
526 
527 	for (i = 0; i < nr_irqs; i++, res++)
528 		if (of_irq_to_resource(dev, i, res) <= 0)
529 			break;
530 
531 	return i;
532 }
533 EXPORT_SYMBOL_GPL(of_irq_to_resource_table);
534 
535 struct of_intc_desc {
536 	struct list_head	list;
537 	of_irq_init_cb_t	irq_init_cb;
538 	struct device_node	*dev;
539 	struct device_node	*interrupt_parent;
540 };
541 
542 /**
543  * of_irq_init - Scan and init matching interrupt controllers in DT
544  * @matches: 0 terminated array of nodes to match and init function to call
545  *
546  * This function scans the device tree for matching interrupt controller nodes,
547  * and calls their initialization functions in order with parents first.
548  */
of_irq_init(const struct of_device_id * matches)549 void __init of_irq_init(const struct of_device_id *matches)
550 {
551 	const struct of_device_id *match;
552 	struct device_node *np, *parent = NULL;
553 	struct of_intc_desc *desc, *temp_desc;
554 	struct list_head intc_desc_list, intc_parent_list;
555 
556 	INIT_LIST_HEAD(&intc_desc_list);
557 	INIT_LIST_HEAD(&intc_parent_list);
558 
559 	for_each_matching_node_and_match(np, matches, &match) {
560 		if (!of_property_read_bool(np, "interrupt-controller") ||
561 				!of_device_is_available(np))
562 			continue;
563 
564 		if (WARN(!match->data, "of_irq_init: no init function for %s\n",
565 			 match->compatible))
566 			continue;
567 
568 		/*
569 		 * Here, we allocate and populate an of_intc_desc with the node
570 		 * pointer, interrupt-parent device_node etc.
571 		 */
572 		desc = kzalloc(sizeof(*desc), GFP_KERNEL);
573 		if (!desc) {
574 			of_node_put(np);
575 			goto err;
576 		}
577 
578 		desc->irq_init_cb = match->data;
579 		desc->dev = of_node_get(np);
580 		/*
581 		 * interrupts-extended can reference multiple parent domains.
582 		 * Arbitrarily pick the first one; assume any other parents
583 		 * are the same distance away from the root irq controller.
584 		 */
585 		desc->interrupt_parent = of_parse_phandle(np, "interrupts-extended", 0);
586 		if (!desc->interrupt_parent)
587 			desc->interrupt_parent = of_irq_find_parent(np);
588 		if (desc->interrupt_parent == np) {
589 			of_node_put(desc->interrupt_parent);
590 			desc->interrupt_parent = NULL;
591 		}
592 		list_add_tail(&desc->list, &intc_desc_list);
593 	}
594 
595 	/*
596 	 * The root irq controller is the one without an interrupt-parent.
597 	 * That one goes first, followed by the controllers that reference it,
598 	 * followed by the ones that reference the 2nd level controllers, etc.
599 	 */
600 	while (!list_empty(&intc_desc_list)) {
601 		/*
602 		 * Process all controllers with the current 'parent'.
603 		 * First pass will be looking for NULL as the parent.
604 		 * The assumption is that NULL parent means a root controller.
605 		 */
606 		list_for_each_entry_safe(desc, temp_desc, &intc_desc_list, list) {
607 			int ret;
608 
609 			if (desc->interrupt_parent != parent)
610 				continue;
611 
612 			list_del(&desc->list);
613 
614 			of_node_set_flag(desc->dev, OF_POPULATED);
615 
616 			pr_debug("of_irq_init: init %pOF (%p), parent %p\n",
617 				 desc->dev,
618 				 desc->dev, desc->interrupt_parent);
619 			ret = desc->irq_init_cb(desc->dev,
620 						desc->interrupt_parent);
621 			if (ret) {
622 				pr_err("%s: Failed to init %pOF (%p), parent %p\n",
623 				       __func__, desc->dev, desc->dev,
624 				       desc->interrupt_parent);
625 				of_node_clear_flag(desc->dev, OF_POPULATED);
626 				kfree(desc);
627 				continue;
628 			}
629 
630 			/*
631 			 * This one is now set up; add it to the parent list so
632 			 * its children can get processed in a subsequent pass.
633 			 */
634 			list_add_tail(&desc->list, &intc_parent_list);
635 		}
636 
637 		/* Get the next pending parent that might have children */
638 		desc = list_first_entry_or_null(&intc_parent_list,
639 						typeof(*desc), list);
640 		if (!desc) {
641 			pr_err("of_irq_init: children remain, but no parents\n");
642 			break;
643 		}
644 		list_del(&desc->list);
645 		parent = desc->dev;
646 		kfree(desc);
647 	}
648 
649 	list_for_each_entry_safe(desc, temp_desc, &intc_parent_list, list) {
650 		list_del(&desc->list);
651 		kfree(desc);
652 	}
653 err:
654 	list_for_each_entry_safe(desc, temp_desc, &intc_desc_list, list) {
655 		list_del(&desc->list);
656 		of_node_put(desc->dev);
657 		kfree(desc);
658 	}
659 }
660 
__of_msi_map_id(struct device * dev,struct device_node ** np,u32 id_in)661 static u32 __of_msi_map_id(struct device *dev, struct device_node **np,
662 			    u32 id_in)
663 {
664 	struct device *parent_dev;
665 	u32 id_out = id_in;
666 
667 	/*
668 	 * Walk up the device parent links looking for one with a
669 	 * "msi-map" property.
670 	 */
671 	for (parent_dev = dev; parent_dev; parent_dev = parent_dev->parent)
672 		if (!of_map_id(parent_dev->of_node, id_in, "msi-map",
673 				"msi-map-mask", np, &id_out))
674 			break;
675 	return id_out;
676 }
677 
678 /**
679  * of_msi_map_id - Map a MSI ID for a device.
680  * @dev: device for which the mapping is to be done.
681  * @msi_np: device node of the expected msi controller.
682  * @id_in: unmapped MSI ID for the device.
683  *
684  * Walk up the device hierarchy looking for devices with a "msi-map"
685  * property.  If found, apply the mapping to @id_in.
686  *
687  * Return: The mapped MSI ID.
688  */
of_msi_map_id(struct device * dev,struct device_node * msi_np,u32 id_in)689 u32 of_msi_map_id(struct device *dev, struct device_node *msi_np, u32 id_in)
690 {
691 	return __of_msi_map_id(dev, &msi_np, id_in);
692 }
693 
694 /**
695  * of_msi_map_get_device_domain - Use msi-map to find the relevant MSI domain
696  * @dev: device for which the mapping is to be done.
697  * @id: Device ID.
698  * @bus_token: Bus token
699  *
700  * Walk up the device hierarchy looking for devices with a "msi-map"
701  * property.
702  *
703  * Returns: the MSI domain for this device (or NULL on failure)
704  */
of_msi_map_get_device_domain(struct device * dev,u32 id,u32 bus_token)705 struct irq_domain *of_msi_map_get_device_domain(struct device *dev, u32 id,
706 						u32 bus_token)
707 {
708 	struct device_node *np = NULL;
709 
710 	__of_msi_map_id(dev, &np, id);
711 	return irq_find_matching_host(np, bus_token);
712 }
713 
714 /**
715  * of_msi_get_domain - Use msi-parent to find the relevant MSI domain
716  * @dev: device for which the domain is requested
717  * @np: device node for @dev
718  * @token: bus type for this domain
719  *
720  * Parse the msi-parent property and returns the corresponding MSI domain.
721  *
722  * Returns: the MSI domain for this device (or NULL on failure).
723  */
of_msi_get_domain(struct device * dev,const struct device_node * np,enum irq_domain_bus_token token)724 struct irq_domain *of_msi_get_domain(struct device *dev,
725 				     const struct device_node *np,
726 				     enum irq_domain_bus_token token)
727 {
728 	struct of_phandle_iterator it;
729 	struct irq_domain *d;
730 	int err;
731 
732 	of_for_each_phandle(&it, err, np, "msi-parent", "#msi-cells", 0) {
733 		d = irq_find_matching_host(it.node, token);
734 		if (d)
735 			return d;
736 	}
737 
738 	return NULL;
739 }
740 EXPORT_SYMBOL_GPL(of_msi_get_domain);
741 
742 /**
743  * of_msi_configure - Set the msi_domain field of a device
744  * @dev: device structure to associate with an MSI irq domain
745  * @np: device node for that device
746  */
of_msi_configure(struct device * dev,const struct device_node * np)747 void of_msi_configure(struct device *dev, const struct device_node *np)
748 {
749 	dev_set_msi_domain(dev,
750 			   of_msi_get_domain(dev, np, DOMAIN_BUS_PLATFORM_MSI));
751 }
752 EXPORT_SYMBOL_GPL(of_msi_configure);
753