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v5.4
  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/**
 29 * irq_of_parse_and_map - Parse and map an interrupt into linux virq space
 30 * @dev: Device node of the device whose interrupt is to be mapped
 31 * @index: Index of the interrupt to map
 32 *
 33 * This function is a wrapper that chains of_irq_parse_one() and
 34 * irq_create_of_mapping() to make things easier to callers
 35 */
 36unsigned int irq_of_parse_and_map(struct device_node *dev, int index)
 37{
 38	struct of_phandle_args oirq;
 39
 40	if (of_irq_parse_one(dev, index, &oirq))
 41		return 0;
 42
 43	return irq_create_of_mapping(&oirq);
 44}
 45EXPORT_SYMBOL_GPL(irq_of_parse_and_map);
 46
 47/**
 48 * of_irq_find_parent - Given a device node, find its interrupt parent node
 49 * @child: pointer to device node
 50 *
 51 * Returns a pointer to the interrupt parent node, or NULL if the interrupt
 52 * parent could not be determined.
 53 */
 54struct device_node *of_irq_find_parent(struct device_node *child)
 55{
 56	struct device_node *p;
 57	phandle parent;
 58
 59	if (!of_node_get(child))
 60		return NULL;
 61
 62	do {
 63		if (of_property_read_u32(child, "interrupt-parent", &parent)) {
 
 64			p = of_get_parent(child);
 65		} else	{
 66			if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
 67				p = of_node_get(of_irq_dflt_pic);
 68			else
 69				p = of_find_node_by_phandle(parent);
 70		}
 71		of_node_put(child);
 72		child = p;
 73	} while (p && of_get_property(p, "#interrupt-cells", NULL) == NULL);
 74
 75	return p;
 76}
 77EXPORT_SYMBOL_GPL(of_irq_find_parent);
 78
 79/**
 80 * of_irq_parse_raw - Low level interrupt tree parsing
 
 81 * @addr:	address specifier (start of "reg" property of the device) in be32 format
 82 * @out_irq:	structure of_phandle_args updated by this function
 83 *
 84 * Returns 0 on success and a negative number on error
 85 *
 86 * This function is a low-level interrupt tree walking function. It
 87 * can be used to do a partial walk with synthetized reg and interrupts
 88 * properties, for example when resolving PCI interrupts when no device
 89 * node exist for the parent. It takes an interrupt specifier structure as
 90 * input, walks the tree looking for any interrupt-map properties, translates
 91 * the specifier for each map, and then returns the translated map.
 92 */
 93int of_irq_parse_raw(const __be32 *addr, struct of_phandle_args *out_irq)
 94{
 95	struct device_node *ipar, *tnode, *old = NULL, *newpar = NULL;
 96	__be32 initial_match_array[MAX_PHANDLE_ARGS];
 97	const __be32 *match_array = initial_match_array;
 98	const __be32 *tmp, *imap, *imask, dummy_imask[] = { [0 ... MAX_PHANDLE_ARGS] = cpu_to_be32(~0) };
 99	u32 intsize = 1, addrsize, newintsize = 0, newaddrsize = 0;
100	int imaplen, match, i, rc = -EINVAL;
101
102#ifdef DEBUG
103	of_print_phandle_args("of_irq_parse_raw: ", out_irq);
104#endif
105
106	ipar = of_node_get(out_irq->np);
107
108	/* First get the #interrupt-cells property of the current cursor
109	 * that tells us how to interpret the passed-in intspec. If there
110	 * is none, we are nice and just walk up the tree
111	 */
112	do {
113		if (!of_property_read_u32(ipar, "#interrupt-cells", &intsize))
 
 
114			break;
 
115		tnode = ipar;
116		ipar = of_irq_find_parent(ipar);
117		of_node_put(tnode);
118	} while (ipar);
119	if (ipar == NULL) {
120		pr_debug(" -> no parent found !\n");
121		goto fail;
122	}
123
124	pr_debug("of_irq_parse_raw: ipar=%pOF, size=%d\n", ipar, intsize);
125
126	if (out_irq->args_count != intsize)
127		goto fail;
128
129	/* Look for this #address-cells. We have to implement the old linux
130	 * trick of looking for the parent here as some device-trees rely on it
131	 */
132	old = of_node_get(ipar);
133	do {
134		tmp = of_get_property(old, "#address-cells", NULL);
135		tnode = of_get_parent(old);
136		of_node_put(old);
137		old = tnode;
138	} while (old && tmp == NULL);
139	of_node_put(old);
140	old = NULL;
141	addrsize = (tmp == NULL) ? 2 : be32_to_cpu(*tmp);
142
143	pr_debug(" -> addrsize=%d\n", addrsize);
144
145	/* Range check so that the temporary buffer doesn't overflow */
146	if (WARN_ON(addrsize + intsize > MAX_PHANDLE_ARGS)) {
147		rc = -EFAULT;
148		goto fail;
149	}
150
151	/* Precalculate the match array - this simplifies match loop */
152	for (i = 0; i < addrsize; i++)
153		initial_match_array[i] = addr ? addr[i] : 0;
154	for (i = 0; i < intsize; i++)
155		initial_match_array[addrsize + i] = cpu_to_be32(out_irq->args[i]);
156
157	/* Now start the actual "proper" walk of the interrupt tree */
158	while (ipar != NULL) {
159		/* Now check if cursor is an interrupt-controller and if it is
160		 * then we are done
161		 */
162		if (of_property_read_bool(ipar, "interrupt-controller")) {
 
163			pr_debug(" -> got it !\n");
164			return 0;
165		}
166
167		/*
168		 * interrupt-map parsing does not work without a reg
169		 * property when #address-cells != 0
170		 */
171		if (addrsize && !addr) {
172			pr_debug(" -> no reg passed in when needed !\n");
173			goto fail;
174		}
175
176		/* Now look for an interrupt-map */
177		imap = of_get_property(ipar, "interrupt-map", &imaplen);
178		/* No interrupt map, check for an interrupt parent */
179		if (imap == NULL) {
180			pr_debug(" -> no map, getting parent\n");
181			newpar = of_irq_find_parent(ipar);
182			goto skiplevel;
183		}
184		imaplen /= sizeof(u32);
185
186		/* Look for a mask */
187		imask = of_get_property(ipar, "interrupt-map-mask", NULL);
188		if (!imask)
189			imask = dummy_imask;
190
191		/* Parse interrupt-map */
192		match = 0;
193		while (imaplen > (addrsize + intsize + 1) && !match) {
194			/* Compare specifiers */
195			match = 1;
196			for (i = 0; i < (addrsize + intsize); i++, imaplen--)
197				match &= !((match_array[i] ^ *imap++) & imask[i]);
198
199			pr_debug(" -> match=%d (imaplen=%d)\n", match, imaplen);
200
201			/* Get the interrupt parent */
202			if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
203				newpar = of_node_get(of_irq_dflt_pic);
204			else
205				newpar = of_find_node_by_phandle(be32_to_cpup(imap));
206			imap++;
207			--imaplen;
208
209			/* Check if not found */
210			if (newpar == NULL) {
211				pr_debug(" -> imap parent not found !\n");
212				goto fail;
213			}
214
215			if (!of_device_is_available(newpar))
216				match = 0;
217
218			/* Get #interrupt-cells and #address-cells of new
219			 * parent
220			 */
221			if (of_property_read_u32(newpar, "#interrupt-cells",
222						 &newintsize)) {
223				pr_debug(" -> parent lacks #interrupt-cells!\n");
224				goto fail;
225			}
226			if (of_property_read_u32(newpar, "#address-cells",
227						 &newaddrsize))
228				newaddrsize = 0;
229
230			pr_debug(" -> newintsize=%d, newaddrsize=%d\n",
231			    newintsize, newaddrsize);
232
233			/* Check for malformed properties */
234			if (WARN_ON(newaddrsize + newintsize > MAX_PHANDLE_ARGS)
235			    || (imaplen < (newaddrsize + newintsize))) {
236				rc = -EFAULT;
237				goto fail;
238			}
239
240			imap += newaddrsize + newintsize;
241			imaplen -= newaddrsize + newintsize;
242
243			pr_debug(" -> imaplen=%d\n", imaplen);
244		}
245		if (!match)
246			goto fail;
247
248		/*
249		 * Successfully parsed an interrrupt-map translation; copy new
250		 * interrupt specifier into the out_irq structure
251		 */
252		match_array = imap - newaddrsize - newintsize;
253		for (i = 0; i < newintsize; i++)
254			out_irq->args[i] = be32_to_cpup(imap - newintsize + i);
255		out_irq->args_count = intsize = newintsize;
256		addrsize = newaddrsize;
257
258	skiplevel:
259		/* Iterate again with new parent */
260		out_irq->np = newpar;
261		pr_debug(" -> new parent: %pOF\n", newpar);
262		of_node_put(ipar);
263		ipar = newpar;
264		newpar = NULL;
265	}
266	rc = -ENOENT; /* No interrupt-map found */
267
268 fail:
269	of_node_put(ipar);
270	of_node_put(newpar);
271
272	return rc;
273}
274EXPORT_SYMBOL_GPL(of_irq_parse_raw);
275
276/**
277 * of_irq_parse_one - Resolve an interrupt for a device
278 * @device: the device whose interrupt is to be resolved
279 * @index: index of the interrupt to resolve
280 * @out_irq: structure of_phandle_args filled by this function
281 *
282 * This function resolves an interrupt for a node by walking the interrupt tree,
283 * finding which interrupt controller node it is attached to, and returning the
284 * interrupt specifier that can be used to retrieve a Linux IRQ number.
285 */
286int of_irq_parse_one(struct device_node *device, int index, struct of_phandle_args *out_irq)
287{
288	struct device_node *p;
289	const __be32 *addr;
290	u32 intsize;
291	int i, res;
292
293	pr_debug("of_irq_parse_one: dev=%pOF, index=%d\n", device, index);
294
295	/* OldWorld mac stuff is "special", handle out of line */
296	if (of_irq_workarounds & OF_IMAP_OLDWORLD_MAC)
297		return of_irq_parse_oldworld(device, index, out_irq);
298
299	/* Get the reg property (if any) */
300	addr = of_get_property(device, "reg", NULL);
301
302	/* Try the new-style interrupts-extended first */
303	res = of_parse_phandle_with_args(device, "interrupts-extended",
304					"#interrupt-cells", index, out_irq);
305	if (!res)
306		return of_irq_parse_raw(addr, out_irq);
307
 
 
 
 
 
 
 
 
 
308	/* Look for the interrupt parent. */
309	p = of_irq_find_parent(device);
310	if (p == NULL)
311		return -EINVAL;
312
313	/* Get size of interrupt specifier */
314	if (of_property_read_u32(p, "#interrupt-cells", &intsize)) {
 
315		res = -EINVAL;
316		goto out;
317	}
 
 
 
318
319	pr_debug(" parent=%pOF, intsize=%d\n", p, intsize);
 
 
 
 
320
321	/* Copy intspec into irq structure */
 
322	out_irq->np = p;
323	out_irq->args_count = intsize;
324	for (i = 0; i < intsize; i++) {
325		res = of_property_read_u32_index(device, "interrupts",
326						 (index * intsize) + i,
327						 out_irq->args + i);
328		if (res)
329			goto out;
330	}
331
332	pr_debug(" intspec=%d\n", *out_irq->args);
333
334
335	/* Check if there are any interrupt-map translations to process */
336	res = of_irq_parse_raw(addr, out_irq);
337 out:
338	of_node_put(p);
339	return res;
340}
341EXPORT_SYMBOL_GPL(of_irq_parse_one);
342
343/**
344 * of_irq_to_resource - Decode a node's IRQ and return it as a resource
345 * @dev: pointer to device tree node
346 * @index: zero-based index of the irq
347 * @r: pointer to resource structure to return result into.
348 */
349int of_irq_to_resource(struct device_node *dev, int index, struct resource *r)
350{
351	int irq = of_irq_get(dev, index);
352
353	if (irq < 0)
354		return irq;
355
356	/* Only dereference the resource if both the
357	 * resource and the irq are valid. */
358	if (r && irq) {
359		const char *name = NULL;
360
361		memset(r, 0, sizeof(*r));
362		/*
363		 * Get optional "interrupt-names" property to add a name
364		 * to the resource.
365		 */
366		of_property_read_string_index(dev, "interrupt-names", index,
367					      &name);
368
369		r->start = r->end = irq;
370		r->flags = IORESOURCE_IRQ | irqd_get_trigger_type(irq_get_irq_data(irq));
371		r->name = name ? name : of_node_full_name(dev);
372	}
373
374	return irq;
375}
376EXPORT_SYMBOL_GPL(of_irq_to_resource);
377
378/**
379 * of_irq_get - Decode a node's IRQ and return it as a Linux IRQ number
380 * @dev: pointer to device tree node
381 * @index: zero-based index of the IRQ
382 *
383 * Returns Linux IRQ number on success, or 0 on the IRQ mapping failure, or
384 * -EPROBE_DEFER if the IRQ domain is not yet created, or error code in case
385 * of any other failure.
386 */
387int of_irq_get(struct device_node *dev, int index)
388{
389	int rc;
390	struct of_phandle_args oirq;
391	struct irq_domain *domain;
392
393	rc = of_irq_parse_one(dev, index, &oirq);
394	if (rc)
395		return rc;
396
397	domain = irq_find_host(oirq.np);
398	if (!domain)
399		return -EPROBE_DEFER;
400
401	return irq_create_of_mapping(&oirq);
402}
403EXPORT_SYMBOL_GPL(of_irq_get);
404
405/**
406 * of_irq_get_byname - Decode a node's IRQ and return it as a Linux IRQ number
407 * @dev: pointer to device tree node
408 * @name: IRQ name
409 *
410 * Returns Linux IRQ number on success, or 0 on the IRQ mapping failure, or
411 * -EPROBE_DEFER if the IRQ domain is not yet created, or error code in case
412 * of any other failure.
413 */
414int of_irq_get_byname(struct device_node *dev, const char *name)
415{
416	int index;
417
418	if (unlikely(!name))
419		return -EINVAL;
420
421	index = of_property_match_string(dev, "interrupt-names", name);
422	if (index < 0)
423		return index;
424
425	return of_irq_get(dev, index);
426}
427EXPORT_SYMBOL_GPL(of_irq_get_byname);
428
429/**
430 * of_irq_count - Count the number of IRQs a node uses
431 * @dev: pointer to device tree node
432 */
433int of_irq_count(struct device_node *dev)
434{
435	struct of_phandle_args irq;
436	int nr = 0;
437
438	while (of_irq_parse_one(dev, nr, &irq) == 0)
439		nr++;
440
441	return nr;
442}
443
444/**
445 * of_irq_to_resource_table - Fill in resource table with node's IRQ info
446 * @dev: pointer to device tree node
447 * @res: array of resources to fill in
448 * @nr_irqs: the number of IRQs (and upper bound for num of @res elements)
449 *
450 * Returns the size of the filled in table (up to @nr_irqs).
451 */
452int of_irq_to_resource_table(struct device_node *dev, struct resource *res,
453		int nr_irqs)
454{
455	int i;
456
457	for (i = 0; i < nr_irqs; i++, res++)
458		if (of_irq_to_resource(dev, i, res) <= 0)
459			break;
460
461	return i;
462}
463EXPORT_SYMBOL_GPL(of_irq_to_resource_table);
464
465struct of_intc_desc {
466	struct list_head	list;
467	of_irq_init_cb_t	irq_init_cb;
468	struct device_node	*dev;
469	struct device_node	*interrupt_parent;
470};
471
472/**
473 * of_irq_init - Scan and init matching interrupt controllers in DT
474 * @matches: 0 terminated array of nodes to match and init function to call
475 *
476 * This function scans the device tree for matching interrupt controller nodes,
477 * and calls their initialization functions in order with parents first.
478 */
479void __init of_irq_init(const struct of_device_id *matches)
480{
481	const struct of_device_id *match;
482	struct device_node *np, *parent = NULL;
483	struct of_intc_desc *desc, *temp_desc;
484	struct list_head intc_desc_list, intc_parent_list;
485
486	INIT_LIST_HEAD(&intc_desc_list);
487	INIT_LIST_HEAD(&intc_parent_list);
488
489	for_each_matching_node_and_match(np, matches, &match) {
490		if (!of_property_read_bool(np, "interrupt-controller") ||
491				!of_device_is_available(np))
492			continue;
493
494		if (WARN(!match->data, "of_irq_init: no init function for %s\n",
495			 match->compatible))
496			continue;
497
498		/*
499		 * Here, we allocate and populate an of_intc_desc with the node
500		 * pointer, interrupt-parent device_node etc.
501		 */
502		desc = kzalloc(sizeof(*desc), GFP_KERNEL);
503		if (!desc) {
504			of_node_put(np);
505			goto err;
506		}
507
508		desc->irq_init_cb = match->data;
509		desc->dev = of_node_get(np);
510		desc->interrupt_parent = of_irq_find_parent(np);
511		if (desc->interrupt_parent == np)
512			desc->interrupt_parent = NULL;
513		list_add_tail(&desc->list, &intc_desc_list);
514	}
515
516	/*
517	 * The root irq controller is the one without an interrupt-parent.
518	 * That one goes first, followed by the controllers that reference it,
519	 * followed by the ones that reference the 2nd level controllers, etc.
520	 */
521	while (!list_empty(&intc_desc_list)) {
522		/*
523		 * Process all controllers with the current 'parent'.
524		 * First pass will be looking for NULL as the parent.
525		 * The assumption is that NULL parent means a root controller.
526		 */
527		list_for_each_entry_safe(desc, temp_desc, &intc_desc_list, list) {
528			int ret;
529
530			if (desc->interrupt_parent != parent)
531				continue;
532
533			list_del(&desc->list);
534
535			of_node_set_flag(desc->dev, OF_POPULATED);
536
537			pr_debug("of_irq_init: init %pOF (%p), parent %p\n",
538				 desc->dev,
539				 desc->dev, desc->interrupt_parent);
540			ret = desc->irq_init_cb(desc->dev,
541						desc->interrupt_parent);
542			if (ret) {
543				of_node_clear_flag(desc->dev, OF_POPULATED);
544				kfree(desc);
545				continue;
546			}
547
548			/*
549			 * This one is now set up; add it to the parent list so
550			 * its children can get processed in a subsequent pass.
551			 */
552			list_add_tail(&desc->list, &intc_parent_list);
553		}
554
555		/* Get the next pending parent that might have children */
556		desc = list_first_entry_or_null(&intc_parent_list,
557						typeof(*desc), list);
558		if (!desc) {
559			pr_err("of_irq_init: children remain, but no parents\n");
560			break;
561		}
562		list_del(&desc->list);
563		parent = desc->dev;
564		kfree(desc);
565	}
566
567	list_for_each_entry_safe(desc, temp_desc, &intc_parent_list, list) {
568		list_del(&desc->list);
569		kfree(desc);
570	}
571err:
572	list_for_each_entry_safe(desc, temp_desc, &intc_desc_list, list) {
573		list_del(&desc->list);
574		of_node_put(desc->dev);
575		kfree(desc);
576	}
577}
578
579static u32 __of_msi_map_rid(struct device *dev, struct device_node **np,
580			    u32 rid_in)
581{
582	struct device *parent_dev;
583	u32 rid_out = rid_in;
584
585	/*
586	 * Walk up the device parent links looking for one with a
587	 * "msi-map" property.
588	 */
589	for (parent_dev = dev; parent_dev; parent_dev = parent_dev->parent)
590		if (!of_map_rid(parent_dev->of_node, rid_in, "msi-map",
591				"msi-map-mask", np, &rid_out))
592			break;
593	return rid_out;
594}
595
596/**
597 * of_msi_map_rid - Map a MSI requester ID for a device.
598 * @dev: device for which the mapping is to be done.
599 * @msi_np: device node of the expected msi controller.
600 * @rid_in: unmapped MSI requester ID for the device.
601 *
602 * Walk up the device hierarchy looking for devices with a "msi-map"
603 * property.  If found, apply the mapping to @rid_in.
604 *
605 * Returns the mapped MSI requester ID.
606 */
607u32 of_msi_map_rid(struct device *dev, struct device_node *msi_np, u32 rid_in)
608{
609	return __of_msi_map_rid(dev, &msi_np, rid_in);
610}
611
612/**
613 * of_msi_map_get_device_domain - Use msi-map to find the relevant MSI domain
614 * @dev: device for which the mapping is to be done.
615 * @rid: Requester ID for the device.
616 *
617 * Walk up the device hierarchy looking for devices with a "msi-map"
618 * property.
619 *
620 * Returns: the MSI domain for this device (or NULL on failure)
621 */
622struct irq_domain *of_msi_map_get_device_domain(struct device *dev, u32 rid)
623{
624	struct device_node *np = NULL;
625
626	__of_msi_map_rid(dev, &np, rid);
627	return irq_find_matching_host(np, DOMAIN_BUS_PCI_MSI);
628}
629
630/**
631 * of_msi_get_domain - Use msi-parent to find the relevant MSI domain
632 * @dev: device for which the domain is requested
633 * @np: device node for @dev
634 * @token: bus type for this domain
635 *
636 * Parse the msi-parent property (both the simple and the complex
637 * versions), and returns the corresponding MSI domain.
638 *
639 * Returns: the MSI domain for this device (or NULL on failure).
640 */
641struct irq_domain *of_msi_get_domain(struct device *dev,
642				     struct device_node *np,
643				     enum irq_domain_bus_token token)
644{
645	struct device_node *msi_np;
646	struct irq_domain *d;
647
648	/* Check for a single msi-parent property */
649	msi_np = of_parse_phandle(np, "msi-parent", 0);
650	if (msi_np && !of_property_read_bool(msi_np, "#msi-cells")) {
651		d = irq_find_matching_host(msi_np, token);
652		if (!d)
653			of_node_put(msi_np);
654		return d;
655	}
656
657	if (token == DOMAIN_BUS_PLATFORM_MSI) {
658		/* Check for the complex msi-parent version */
659		struct of_phandle_args args;
660		int index = 0;
661
662		while (!of_parse_phandle_with_args(np, "msi-parent",
663						   "#msi-cells",
664						   index, &args)) {
665			d = irq_find_matching_host(args.np, token);
666			if (d)
667				return d;
668
669			of_node_put(args.np);
670			index++;
671		}
672	}
673
674	return NULL;
675}
676
677/**
678 * of_msi_configure - Set the msi_domain field of a device
679 * @dev: device structure to associate with an MSI irq domain
680 * @np: device node for that device
681 */
682void of_msi_configure(struct device *dev, struct device_node *np)
683{
684	dev_set_msi_domain(dev,
685			   of_msi_get_domain(dev, np, DOMAIN_BUS_PLATFORM_MSI));
686}
687EXPORT_SYMBOL_GPL(of_msi_configure);
v4.10.11
 
  1/*
  2 *  Derived from arch/i386/kernel/irq.c
  3 *    Copyright (C) 1992 Linus Torvalds
  4 *  Adapted from arch/i386 by Gary Thomas
  5 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
  6 *  Updated and modified by Cort Dougan <cort@fsmlabs.com>
  7 *    Copyright (C) 1996-2001 Cort Dougan
  8 *  Adapted for Power Macintosh by Paul Mackerras
  9 *    Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au)
 10 *
 11 * This program is free software; you can redistribute it and/or
 12 * modify it under the terms of the GNU General Public License
 13 * as published by the Free Software Foundation; either version
 14 * 2 of the License, or (at your option) any later version.
 15 *
 16 * This file contains the code used to make IRQ descriptions in the
 17 * device tree to actual irq numbers on an interrupt controller
 18 * driver.
 19 */
 20
 21#define pr_fmt(fmt)	"OF: " fmt
 22
 23#include <linux/device.h>
 24#include <linux/errno.h>
 25#include <linux/list.h>
 26#include <linux/module.h>
 27#include <linux/of.h>
 28#include <linux/of_irq.h>
 29#include <linux/of_pci.h>
 30#include <linux/string.h>
 31#include <linux/slab.h>
 32
 33/**
 34 * irq_of_parse_and_map - Parse and map an interrupt into linux virq space
 35 * @dev: Device node of the device whose interrupt is to be mapped
 36 * @index: Index of the interrupt to map
 37 *
 38 * This function is a wrapper that chains of_irq_parse_one() and
 39 * irq_create_of_mapping() to make things easier to callers
 40 */
 41unsigned int irq_of_parse_and_map(struct device_node *dev, int index)
 42{
 43	struct of_phandle_args oirq;
 44
 45	if (of_irq_parse_one(dev, index, &oirq))
 46		return 0;
 47
 48	return irq_create_of_mapping(&oirq);
 49}
 50EXPORT_SYMBOL_GPL(irq_of_parse_and_map);
 51
 52/**
 53 * of_irq_find_parent - Given a device node, find its interrupt parent node
 54 * @child: pointer to device node
 55 *
 56 * Returns a pointer to the interrupt parent node, or NULL if the interrupt
 57 * parent could not be determined.
 58 */
 59struct device_node *of_irq_find_parent(struct device_node *child)
 60{
 61	struct device_node *p;
 62	const __be32 *parp;
 63
 64	if (!of_node_get(child))
 65		return NULL;
 66
 67	do {
 68		parp = of_get_property(child, "interrupt-parent", NULL);
 69		if (parp == NULL)
 70			p = of_get_parent(child);
 71		else {
 72			if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
 73				p = of_node_get(of_irq_dflt_pic);
 74			else
 75				p = of_find_node_by_phandle(be32_to_cpup(parp));
 76		}
 77		of_node_put(child);
 78		child = p;
 79	} while (p && of_get_property(p, "#interrupt-cells", NULL) == NULL);
 80
 81	return p;
 82}
 83EXPORT_SYMBOL_GPL(of_irq_find_parent);
 84
 85/**
 86 * of_irq_parse_raw - Low level interrupt tree parsing
 87 * @parent:	the device interrupt parent
 88 * @addr:	address specifier (start of "reg" property of the device) in be32 format
 89 * @out_irq:	structure of_irq updated by this function
 90 *
 91 * Returns 0 on success and a negative number on error
 92 *
 93 * This function is a low-level interrupt tree walking function. It
 94 * can be used to do a partial walk with synthetized reg and interrupts
 95 * properties, for example when resolving PCI interrupts when no device
 96 * node exist for the parent. It takes an interrupt specifier structure as
 97 * input, walks the tree looking for any interrupt-map properties, translates
 98 * the specifier for each map, and then returns the translated map.
 99 */
100int of_irq_parse_raw(const __be32 *addr, struct of_phandle_args *out_irq)
101{
102	struct device_node *ipar, *tnode, *old = NULL, *newpar = NULL;
103	__be32 initial_match_array[MAX_PHANDLE_ARGS];
104	const __be32 *match_array = initial_match_array;
105	const __be32 *tmp, *imap, *imask, dummy_imask[] = { [0 ... MAX_PHANDLE_ARGS] = ~0 };
106	u32 intsize = 1, addrsize, newintsize = 0, newaddrsize = 0;
107	int imaplen, match, i;
108
109#ifdef DEBUG
110	of_print_phandle_args("of_irq_parse_raw: ", out_irq);
111#endif
112
113	ipar = of_node_get(out_irq->np);
114
115	/* First get the #interrupt-cells property of the current cursor
116	 * that tells us how to interpret the passed-in intspec. If there
117	 * is none, we are nice and just walk up the tree
118	 */
119	do {
120		tmp = of_get_property(ipar, "#interrupt-cells", NULL);
121		if (tmp != NULL) {
122			intsize = be32_to_cpu(*tmp);
123			break;
124		}
125		tnode = ipar;
126		ipar = of_irq_find_parent(ipar);
127		of_node_put(tnode);
128	} while (ipar);
129	if (ipar == NULL) {
130		pr_debug(" -> no parent found !\n");
131		goto fail;
132	}
133
134	pr_debug("of_irq_parse_raw: ipar=%s, size=%d\n", of_node_full_name(ipar), intsize);
135
136	if (out_irq->args_count != intsize)
137		return -EINVAL;
138
139	/* Look for this #address-cells. We have to implement the old linux
140	 * trick of looking for the parent here as some device-trees rely on it
141	 */
142	old = of_node_get(ipar);
143	do {
144		tmp = of_get_property(old, "#address-cells", NULL);
145		tnode = of_get_parent(old);
146		of_node_put(old);
147		old = tnode;
148	} while (old && tmp == NULL);
149	of_node_put(old);
150	old = NULL;
151	addrsize = (tmp == NULL) ? 2 : be32_to_cpu(*tmp);
152
153	pr_debug(" -> addrsize=%d\n", addrsize);
154
155	/* Range check so that the temporary buffer doesn't overflow */
156	if (WARN_ON(addrsize + intsize > MAX_PHANDLE_ARGS))
 
157		goto fail;
 
158
159	/* Precalculate the match array - this simplifies match loop */
160	for (i = 0; i < addrsize; i++)
161		initial_match_array[i] = addr ? addr[i] : 0;
162	for (i = 0; i < intsize; i++)
163		initial_match_array[addrsize + i] = cpu_to_be32(out_irq->args[i]);
164
165	/* Now start the actual "proper" walk of the interrupt tree */
166	while (ipar != NULL) {
167		/* Now check if cursor is an interrupt-controller and if it is
168		 * then we are done
169		 */
170		if (of_get_property(ipar, "interrupt-controller", NULL) !=
171				NULL) {
172			pr_debug(" -> got it !\n");
173			return 0;
174		}
175
176		/*
177		 * interrupt-map parsing does not work without a reg
178		 * property when #address-cells != 0
179		 */
180		if (addrsize && !addr) {
181			pr_debug(" -> no reg passed in when needed !\n");
182			goto fail;
183		}
184
185		/* Now look for an interrupt-map */
186		imap = of_get_property(ipar, "interrupt-map", &imaplen);
187		/* No interrupt map, check for an interrupt parent */
188		if (imap == NULL) {
189			pr_debug(" -> no map, getting parent\n");
190			newpar = of_irq_find_parent(ipar);
191			goto skiplevel;
192		}
193		imaplen /= sizeof(u32);
194
195		/* Look for a mask */
196		imask = of_get_property(ipar, "interrupt-map-mask", NULL);
197		if (!imask)
198			imask = dummy_imask;
199
200		/* Parse interrupt-map */
201		match = 0;
202		while (imaplen > (addrsize + intsize + 1) && !match) {
203			/* Compare specifiers */
204			match = 1;
205			for (i = 0; i < (addrsize + intsize); i++, imaplen--)
206				match &= !((match_array[i] ^ *imap++) & imask[i]);
207
208			pr_debug(" -> match=%d (imaplen=%d)\n", match, imaplen);
209
210			/* Get the interrupt parent */
211			if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
212				newpar = of_node_get(of_irq_dflt_pic);
213			else
214				newpar = of_find_node_by_phandle(be32_to_cpup(imap));
215			imap++;
216			--imaplen;
217
218			/* Check if not found */
219			if (newpar == NULL) {
220				pr_debug(" -> imap parent not found !\n");
221				goto fail;
222			}
223
224			if (!of_device_is_available(newpar))
225				match = 0;
226
227			/* Get #interrupt-cells and #address-cells of new
228			 * parent
229			 */
230			tmp = of_get_property(newpar, "#interrupt-cells", NULL);
231			if (tmp == NULL) {
232				pr_debug(" -> parent lacks #interrupt-cells!\n");
233				goto fail;
234			}
235			newintsize = be32_to_cpu(*tmp);
236			tmp = of_get_property(newpar, "#address-cells", NULL);
237			newaddrsize = (tmp == NULL) ? 0 : be32_to_cpu(*tmp);
238
239			pr_debug(" -> newintsize=%d, newaddrsize=%d\n",
240			    newintsize, newaddrsize);
241
242			/* Check for malformed properties */
243			if (WARN_ON(newaddrsize + newintsize > MAX_PHANDLE_ARGS))
244				goto fail;
245			if (imaplen < (newaddrsize + newintsize))
246				goto fail;
 
247
248			imap += newaddrsize + newintsize;
249			imaplen -= newaddrsize + newintsize;
250
251			pr_debug(" -> imaplen=%d\n", imaplen);
252		}
253		if (!match)
254			goto fail;
255
256		/*
257		 * Successfully parsed an interrrupt-map translation; copy new
258		 * interrupt specifier into the out_irq structure
259		 */
260		match_array = imap - newaddrsize - newintsize;
261		for (i = 0; i < newintsize; i++)
262			out_irq->args[i] = be32_to_cpup(imap - newintsize + i);
263		out_irq->args_count = intsize = newintsize;
264		addrsize = newaddrsize;
265
266	skiplevel:
267		/* Iterate again with new parent */
268		out_irq->np = newpar;
269		pr_debug(" -> new parent: %s\n", of_node_full_name(newpar));
270		of_node_put(ipar);
271		ipar = newpar;
272		newpar = NULL;
273	}
 
 
274 fail:
275	of_node_put(ipar);
276	of_node_put(newpar);
277
278	return -EINVAL;
279}
280EXPORT_SYMBOL_GPL(of_irq_parse_raw);
281
282/**
283 * of_irq_parse_one - Resolve an interrupt for a device
284 * @device: the device whose interrupt is to be resolved
285 * @index: index of the interrupt to resolve
286 * @out_irq: structure of_irq filled by this function
287 *
288 * This function resolves an interrupt for a node by walking the interrupt tree,
289 * finding which interrupt controller node it is attached to, and returning the
290 * interrupt specifier that can be used to retrieve a Linux IRQ number.
291 */
292int of_irq_parse_one(struct device_node *device, int index, struct of_phandle_args *out_irq)
293{
294	struct device_node *p;
295	const __be32 *intspec, *tmp, *addr;
296	u32 intsize, intlen;
297	int i, res;
298
299	pr_debug("of_irq_parse_one: dev=%s, index=%d\n", of_node_full_name(device), index);
300
301	/* OldWorld mac stuff is "special", handle out of line */
302	if (of_irq_workarounds & OF_IMAP_OLDWORLD_MAC)
303		return of_irq_parse_oldworld(device, index, out_irq);
304
305	/* Get the reg property (if any) */
306	addr = of_get_property(device, "reg", NULL);
307
308	/* Try the new-style interrupts-extended first */
309	res = of_parse_phandle_with_args(device, "interrupts-extended",
310					"#interrupt-cells", index, out_irq);
311	if (!res)
312		return of_irq_parse_raw(addr, out_irq);
313
314	/* Get the interrupts property */
315	intspec = of_get_property(device, "interrupts", &intlen);
316	if (intspec == NULL)
317		return -EINVAL;
318
319	intlen /= sizeof(*intspec);
320
321	pr_debug(" intspec=%d intlen=%d\n", be32_to_cpup(intspec), intlen);
322
323	/* Look for the interrupt parent. */
324	p = of_irq_find_parent(device);
325	if (p == NULL)
326		return -EINVAL;
327
328	/* Get size of interrupt specifier */
329	tmp = of_get_property(p, "#interrupt-cells", NULL);
330	if (tmp == NULL) {
331		res = -EINVAL;
332		goto out;
333	}
334	intsize = be32_to_cpu(*tmp);
335
336	pr_debug(" intsize=%d intlen=%d\n", intsize, intlen);
337
338	/* Check index */
339	if ((index + 1) * intsize > intlen) {
340		res = -EINVAL;
341		goto out;
342	}
343
344	/* Copy intspec into irq structure */
345	intspec += index * intsize;
346	out_irq->np = p;
347	out_irq->args_count = intsize;
348	for (i = 0; i < intsize; i++)
349		out_irq->args[i] = be32_to_cpup(intspec++);
 
 
 
 
 
 
 
 
350
351	/* Check if there are any interrupt-map translations to process */
352	res = of_irq_parse_raw(addr, out_irq);
353 out:
354	of_node_put(p);
355	return res;
356}
357EXPORT_SYMBOL_GPL(of_irq_parse_one);
358
359/**
360 * of_irq_to_resource - Decode a node's IRQ and return it as a resource
361 * @dev: pointer to device tree node
362 * @index: zero-based index of the irq
363 * @r: pointer to resource structure to return result into.
364 */
365int of_irq_to_resource(struct device_node *dev, int index, struct resource *r)
366{
367	int irq = irq_of_parse_and_map(dev, index);
 
 
 
368
369	/* Only dereference the resource if both the
370	 * resource and the irq are valid. */
371	if (r && irq) {
372		const char *name = NULL;
373
374		memset(r, 0, sizeof(*r));
375		/*
376		 * Get optional "interrupt-names" property to add a name
377		 * to the resource.
378		 */
379		of_property_read_string_index(dev, "interrupt-names", index,
380					      &name);
381
382		r->start = r->end = irq;
383		r->flags = IORESOURCE_IRQ | irqd_get_trigger_type(irq_get_irq_data(irq));
384		r->name = name ? name : of_node_full_name(dev);
385	}
386
387	return irq;
388}
389EXPORT_SYMBOL_GPL(of_irq_to_resource);
390
391/**
392 * of_irq_get - Decode a node's IRQ and return it as a Linux IRQ number
393 * @dev: pointer to device tree node
394 * @index: zero-based index of the IRQ
395 *
396 * Returns Linux IRQ number on success, or 0 on the IRQ mapping failure, or
397 * -EPROBE_DEFER if the IRQ domain is not yet created, or error code in case
398 * of any other failure.
399 */
400int of_irq_get(struct device_node *dev, int index)
401{
402	int rc;
403	struct of_phandle_args oirq;
404	struct irq_domain *domain;
405
406	rc = of_irq_parse_one(dev, index, &oirq);
407	if (rc)
408		return rc;
409
410	domain = irq_find_host(oirq.np);
411	if (!domain)
412		return -EPROBE_DEFER;
413
414	return irq_create_of_mapping(&oirq);
415}
416EXPORT_SYMBOL_GPL(of_irq_get);
417
418/**
419 * of_irq_get_byname - Decode a node's IRQ and return it as a Linux IRQ number
420 * @dev: pointer to device tree node
421 * @name: IRQ name
422 *
423 * Returns Linux IRQ number on success, or 0 on the IRQ mapping failure, or
424 * -EPROBE_DEFER if the IRQ domain is not yet created, or error code in case
425 * of any other failure.
426 */
427int of_irq_get_byname(struct device_node *dev, const char *name)
428{
429	int index;
430
431	if (unlikely(!name))
432		return -EINVAL;
433
434	index = of_property_match_string(dev, "interrupt-names", name);
435	if (index < 0)
436		return index;
437
438	return of_irq_get(dev, index);
439}
440EXPORT_SYMBOL_GPL(of_irq_get_byname);
441
442/**
443 * of_irq_count - Count the number of IRQs a node uses
444 * @dev: pointer to device tree node
445 */
446int of_irq_count(struct device_node *dev)
447{
448	struct of_phandle_args irq;
449	int nr = 0;
450
451	while (of_irq_parse_one(dev, nr, &irq) == 0)
452		nr++;
453
454	return nr;
455}
456
457/**
458 * of_irq_to_resource_table - Fill in resource table with node's IRQ info
459 * @dev: pointer to device tree node
460 * @res: array of resources to fill in
461 * @nr_irqs: the number of IRQs (and upper bound for num of @res elements)
462 *
463 * Returns the size of the filled in table (up to @nr_irqs).
464 */
465int of_irq_to_resource_table(struct device_node *dev, struct resource *res,
466		int nr_irqs)
467{
468	int i;
469
470	for (i = 0; i < nr_irqs; i++, res++)
471		if (!of_irq_to_resource(dev, i, res))
472			break;
473
474	return i;
475}
476EXPORT_SYMBOL_GPL(of_irq_to_resource_table);
477
478struct of_intc_desc {
479	struct list_head	list;
480	of_irq_init_cb_t	irq_init_cb;
481	struct device_node	*dev;
482	struct device_node	*interrupt_parent;
483};
484
485/**
486 * of_irq_init - Scan and init matching interrupt controllers in DT
487 * @matches: 0 terminated array of nodes to match and init function to call
488 *
489 * This function scans the device tree for matching interrupt controller nodes,
490 * and calls their initialization functions in order with parents first.
491 */
492void __init of_irq_init(const struct of_device_id *matches)
493{
494	const struct of_device_id *match;
495	struct device_node *np, *parent = NULL;
496	struct of_intc_desc *desc, *temp_desc;
497	struct list_head intc_desc_list, intc_parent_list;
498
499	INIT_LIST_HEAD(&intc_desc_list);
500	INIT_LIST_HEAD(&intc_parent_list);
501
502	for_each_matching_node_and_match(np, matches, &match) {
503		if (!of_find_property(np, "interrupt-controller", NULL) ||
504				!of_device_is_available(np))
505			continue;
506
507		if (WARN(!match->data, "of_irq_init: no init function for %s\n",
508			 match->compatible))
509			continue;
510
511		/*
512		 * Here, we allocate and populate an of_intc_desc with the node
513		 * pointer, interrupt-parent device_node etc.
514		 */
515		desc = kzalloc(sizeof(*desc), GFP_KERNEL);
516		if (WARN_ON(!desc)) {
517			of_node_put(np);
518			goto err;
519		}
520
521		desc->irq_init_cb = match->data;
522		desc->dev = of_node_get(np);
523		desc->interrupt_parent = of_irq_find_parent(np);
524		if (desc->interrupt_parent == np)
525			desc->interrupt_parent = NULL;
526		list_add_tail(&desc->list, &intc_desc_list);
527	}
528
529	/*
530	 * The root irq controller is the one without an interrupt-parent.
531	 * That one goes first, followed by the controllers that reference it,
532	 * followed by the ones that reference the 2nd level controllers, etc.
533	 */
534	while (!list_empty(&intc_desc_list)) {
535		/*
536		 * Process all controllers with the current 'parent'.
537		 * First pass will be looking for NULL as the parent.
538		 * The assumption is that NULL parent means a root controller.
539		 */
540		list_for_each_entry_safe(desc, temp_desc, &intc_desc_list, list) {
541			int ret;
542
543			if (desc->interrupt_parent != parent)
544				continue;
545
546			list_del(&desc->list);
547
548			of_node_set_flag(desc->dev, OF_POPULATED);
549
550			pr_debug("of_irq_init: init %s (%p), parent %p\n",
551				 desc->dev->full_name,
552				 desc->dev, desc->interrupt_parent);
553			ret = desc->irq_init_cb(desc->dev,
554						desc->interrupt_parent);
555			if (ret) {
556				of_node_clear_flag(desc->dev, OF_POPULATED);
557				kfree(desc);
558				continue;
559			}
560
561			/*
562			 * This one is now set up; add it to the parent list so
563			 * its children can get processed in a subsequent pass.
564			 */
565			list_add_tail(&desc->list, &intc_parent_list);
566		}
567
568		/* Get the next pending parent that might have children */
569		desc = list_first_entry_or_null(&intc_parent_list,
570						typeof(*desc), list);
571		if (!desc) {
572			pr_err("of_irq_init: children remain, but no parents\n");
573			break;
574		}
575		list_del(&desc->list);
576		parent = desc->dev;
577		kfree(desc);
578	}
579
580	list_for_each_entry_safe(desc, temp_desc, &intc_parent_list, list) {
581		list_del(&desc->list);
582		kfree(desc);
583	}
584err:
585	list_for_each_entry_safe(desc, temp_desc, &intc_desc_list, list) {
586		list_del(&desc->list);
587		of_node_put(desc->dev);
588		kfree(desc);
589	}
590}
591
592static u32 __of_msi_map_rid(struct device *dev, struct device_node **np,
593			    u32 rid_in)
594{
595	struct device *parent_dev;
596	u32 rid_out = rid_in;
597
598	/*
599	 * Walk up the device parent links looking for one with a
600	 * "msi-map" property.
601	 */
602	for (parent_dev = dev; parent_dev; parent_dev = parent_dev->parent)
603		if (!of_pci_map_rid(parent_dev->of_node, rid_in, "msi-map",
604				    "msi-map-mask", np, &rid_out))
605			break;
606	return rid_out;
607}
608
609/**
610 * of_msi_map_rid - Map a MSI requester ID for a device.
611 * @dev: device for which the mapping is to be done.
612 * @msi_np: device node of the expected msi controller.
613 * @rid_in: unmapped MSI requester ID for the device.
614 *
615 * Walk up the device hierarchy looking for devices with a "msi-map"
616 * property.  If found, apply the mapping to @rid_in.
617 *
618 * Returns the mapped MSI requester ID.
619 */
620u32 of_msi_map_rid(struct device *dev, struct device_node *msi_np, u32 rid_in)
621{
622	return __of_msi_map_rid(dev, &msi_np, rid_in);
623}
624
625/**
626 * of_msi_map_get_device_domain - Use msi-map to find the relevant MSI domain
627 * @dev: device for which the mapping is to be done.
628 * @rid: Requester ID for the device.
629 *
630 * Walk up the device hierarchy looking for devices with a "msi-map"
631 * property.
632 *
633 * Returns: the MSI domain for this device (or NULL on failure)
634 */
635struct irq_domain *of_msi_map_get_device_domain(struct device *dev, u32 rid)
636{
637	struct device_node *np = NULL;
638
639	__of_msi_map_rid(dev, &np, rid);
640	return irq_find_matching_host(np, DOMAIN_BUS_PCI_MSI);
641}
642
643/**
644 * of_msi_get_domain - Use msi-parent to find the relevant MSI domain
645 * @dev: device for which the domain is requested
646 * @np: device node for @dev
647 * @token: bus type for this domain
648 *
649 * Parse the msi-parent property (both the simple and the complex
650 * versions), and returns the corresponding MSI domain.
651 *
652 * Returns: the MSI domain for this device (or NULL on failure).
653 */
654struct irq_domain *of_msi_get_domain(struct device *dev,
655				     struct device_node *np,
656				     enum irq_domain_bus_token token)
657{
658	struct device_node *msi_np;
659	struct irq_domain *d;
660
661	/* Check for a single msi-parent property */
662	msi_np = of_parse_phandle(np, "msi-parent", 0);
663	if (msi_np && !of_property_read_bool(msi_np, "#msi-cells")) {
664		d = irq_find_matching_host(msi_np, token);
665		if (!d)
666			of_node_put(msi_np);
667		return d;
668	}
669
670	if (token == DOMAIN_BUS_PLATFORM_MSI) {
671		/* Check for the complex msi-parent version */
672		struct of_phandle_args args;
673		int index = 0;
674
675		while (!of_parse_phandle_with_args(np, "msi-parent",
676						   "#msi-cells",
677						   index, &args)) {
678			d = irq_find_matching_host(args.np, token);
679			if (d)
680				return d;
681
682			of_node_put(args.np);
683			index++;
684		}
685	}
686
687	return NULL;
688}
689
690/**
691 * of_msi_configure - Set the msi_domain field of a device
692 * @dev: device structure to associate with an MSI irq domain
693 * @np: device node for that device
694 */
695void of_msi_configure(struct device *dev, struct device_node *np)
696{
697	dev_set_msi_domain(dev,
698			   of_msi_get_domain(dev, np, DOMAIN_BUS_PLATFORM_MSI));
699}
700EXPORT_SYMBOL_GPL(of_msi_configure);