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1// SPDX-License-Identifier: GPL-2.0+2/*3 *  Derived from arch/i386/kernel/irq.c4 *    Copyright (C) 1992 Linus Torvalds5 *  Adapted from arch/i386 by Gary Thomas6 *    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 Dougan9 *  Adapted for Power Macintosh by Paul Mackerras10 *    Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au)11 *12 * This file contains the code used to make IRQ descriptions in the13 * device tree to actual irq numbers on an interrupt controller14 * driver.15 */16 17#define pr_fmt(fmt)	"OF: " fmt18 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 space32 * @dev: Device node of the device whose interrupt is to be mapped33 * @index: Index of the interrupt to map34 *35 * This function is a wrapper that chains of_irq_parse_one() and36 * irq_create_of_mapping() to make things easier to callers37 */38unsigned 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}47EXPORT_SYMBOL_GPL(irq_of_parse_and_map);48 49/**50 * of_irq_find_parent - Given a device node, find its interrupt parent node51 * @child: pointer to device node52 *53 * Return: A pointer to the interrupt parent node, or NULL if the interrupt54 * parent could not be determined.55 */56struct 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			else71				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}79EXPORT_SYMBOL_GPL(of_irq_find_parent);80 81/*82 * These interrupt controllers abuse interrupt-map for unspeakable83 * reasons and rely on the core code to *ignore* it (the drivers do84 * their own parsing of the property). The PAsemi entry covers a85 * non-sensical interrupt-map that is better left ignored.86 *87 * If you think of adding to the list for something *new*, think88 * again. There is a high chance that you will be sent back to the89 * drawing board.90 */91static 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 103const __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	else112		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 parsing156 * @addr:	address specifier (start of "reg" property of the device) in be32 format157 * @out_irq:	structure of_phandle_args updated by this function158 *159 * This function is a low-level interrupt tree walking function. It160 * can be used to do a partial walk with synthetized reg and interrupts161 * properties, for example when resolving PCI interrupts when no device162 * node exist for the parent. It takes an interrupt specifier structure as163 * input, walks the tree looking for any interrupt-map properties, translates164 * the specifier for each map, and then returns the translated map.165 *166 * Return: 0 on success and a negative number on error167 */168int 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 DEBUG178	of_print_phandle_args("of_irq_parse_raw: ", out_irq);179#endif180 181	ipar = of_node_get(out_irq->np);182 183	/* First get the #interrupt-cells property of the current cursor184	 * that tells us how to interpret the passed-in intspec. If there185	 * is none, we are nice and just walk up the tree186	 */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 linux205	 * trick of looking for the parent here as some device-trees rely on it206	 */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 and239		 * if it is then we are done, unless there is an240		 * interrupt-map which takes precedence except on one241		 * of these broken platforms that want to parse242		 * 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 reg255		 * property when #address-cells != 0256		 */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 new303		 * interrupt specifier into the out_irq structure304		 */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}330EXPORT_SYMBOL_GPL(of_irq_parse_raw);331 332/**333 * of_irq_parse_one - Resolve an interrupt for a device334 * @device: the device whose interrupt is to be resolved335 * @index: index of the interrupt to resolve336 * @out_irq: structure of_phandle_args filled by this function337 *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 the340 * interrupt specifier that can be used to retrieve a Linux IRQ number.341 */342int 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, addr_len;348	__be32 addr_buf[3] = { 0 };349 350	pr_debug("of_irq_parse_one: dev=%pOF, index=%d\n", device, index);351 352	/* OldWorld mac stuff is "special", handle out of line */353	if (of_irq_workarounds & OF_IMAP_OLDWORLD_MAC)354		return of_irq_parse_oldworld(device, index, out_irq);355 356	/* Get the reg property (if any) */357	addr = of_get_property(device, "reg", &addr_len);358 359	/* Prevent out-of-bounds read in case of longer interrupt parent address size */360	if (addr_len > sizeof(addr_buf))361		addr_len = sizeof(addr_buf);362	if (addr)363		memcpy(addr_buf, addr, addr_len);364 365	/* Try the new-style interrupts-extended first */366	res = of_parse_phandle_with_args(device, "interrupts-extended",367					"#interrupt-cells", index, out_irq);368	if (!res)369		return of_irq_parse_raw(addr_buf, out_irq);370 371	/* Look for the interrupt parent. */372	p = of_irq_find_parent(device);373	if (p == NULL)374		return -EINVAL;375 376	/* Get size of interrupt specifier */377	if (of_property_read_u32(p, "#interrupt-cells", &intsize)) {378		res = -EINVAL;379		goto out;380	}381 382	pr_debug(" parent=%pOF, intsize=%d\n", p, intsize);383 384	/* Copy intspec into irq structure */385	out_irq->np = p;386	out_irq->args_count = intsize;387	for (i = 0; i < intsize; i++) {388		res = of_property_read_u32_index(device, "interrupts",389						 (index * intsize) + i,390						 out_irq->args + i);391		if (res)392			goto out;393	}394 395	pr_debug(" intspec=%d\n", *out_irq->args);396 397 398	/* Check if there are any interrupt-map translations to process */399	res = of_irq_parse_raw(addr_buf, out_irq);400 out:401	of_node_put(p);402	return res;403}404EXPORT_SYMBOL_GPL(of_irq_parse_one);405 406/**407 * of_irq_to_resource - Decode a node's IRQ and return it as a resource408 * @dev: pointer to device tree node409 * @index: zero-based index of the irq410 * @r: pointer to resource structure to return result into.411 */412int of_irq_to_resource(struct device_node *dev, int index, struct resource *r)413{414	int irq = of_irq_get(dev, index);415 416	if (irq < 0)417		return irq;418 419	/* Only dereference the resource if both the420	 * resource and the irq are valid. */421	if (r && irq) {422		const char *name = NULL;423 424		memset(r, 0, sizeof(*r));425		/*426		 * Get optional "interrupt-names" property to add a name427		 * to the resource.428		 */429		of_property_read_string_index(dev, "interrupt-names", index,430					      &name);431 432		*r = DEFINE_RES_IRQ_NAMED(irq, name ?: of_node_full_name(dev));433		r->flags |= irq_get_trigger_type(irq);434	}435 436	return irq;437}438EXPORT_SYMBOL_GPL(of_irq_to_resource);439 440/**441 * of_irq_get - Decode a node's IRQ and return it as a Linux IRQ number442 * @dev: pointer to device tree node443 * @index: zero-based index of the IRQ444 *445 * Return: Linux IRQ number on success, or 0 on the IRQ mapping failure, or446 * -EPROBE_DEFER if the IRQ domain is not yet created, or error code in case447 * of any other failure.448 */449int of_irq_get(struct device_node *dev, int index)450{451	int rc;452	struct of_phandle_args oirq;453	struct irq_domain *domain;454 455	rc = of_irq_parse_one(dev, index, &oirq);456	if (rc)457		return rc;458 459	domain = irq_find_host(oirq.np);460	if (!domain) {461		rc = -EPROBE_DEFER;462		goto out;463	}464 465	rc = irq_create_of_mapping(&oirq);466out:467	of_node_put(oirq.np);468 469	return rc;470}471EXPORT_SYMBOL_GPL(of_irq_get);472 473/**474 * of_irq_get_byname - Decode a node's IRQ and return it as a Linux IRQ number475 * @dev: pointer to device tree node476 * @name: IRQ name477 *478 * Return: Linux IRQ number on success, or 0 on the IRQ mapping failure, or479 * -EPROBE_DEFER if the IRQ domain is not yet created, or error code in case480 * of any other failure.481 */482int of_irq_get_byname(struct device_node *dev, const char *name)483{484	int index;485 486	if (unlikely(!name))487		return -EINVAL;488 489	index = of_property_match_string(dev, "interrupt-names", name);490	if (index < 0)491		return index;492 493	return of_irq_get(dev, index);494}495EXPORT_SYMBOL_GPL(of_irq_get_byname);496 497/**498 * of_irq_count - Count the number of IRQs a node uses499 * @dev: pointer to device tree node500 */501int of_irq_count(struct device_node *dev)502{503	struct of_phandle_args irq;504	int nr = 0;505 506	while (of_irq_parse_one(dev, nr, &irq) == 0)507		nr++;508 509	return nr;510}511 512/**513 * of_irq_to_resource_table - Fill in resource table with node's IRQ info514 * @dev: pointer to device tree node515 * @res: array of resources to fill in516 * @nr_irqs: the number of IRQs (and upper bound for num of @res elements)517 *518 * Return: The size of the filled in table (up to @nr_irqs).519 */520int of_irq_to_resource_table(struct device_node *dev, struct resource *res,521		int nr_irqs)522{523	int i;524 525	for (i = 0; i < nr_irqs; i++, res++)526		if (of_irq_to_resource(dev, i, res) <= 0)527			break;528 529	return i;530}531EXPORT_SYMBOL_GPL(of_irq_to_resource_table);532 533struct of_intc_desc {534	struct list_head	list;535	of_irq_init_cb_t	irq_init_cb;536	struct device_node	*dev;537	struct device_node	*interrupt_parent;538};539 540/**541 * of_irq_init - Scan and init matching interrupt controllers in DT542 * @matches: 0 terminated array of nodes to match and init function to call543 *544 * This function scans the device tree for matching interrupt controller nodes,545 * and calls their initialization functions in order with parents first.546 */547void __init of_irq_init(const struct of_device_id *matches)548{549	const struct of_device_id *match;550	struct device_node *np, *parent = NULL;551	struct of_intc_desc *desc, *temp_desc;552	struct list_head intc_desc_list, intc_parent_list;553 554	INIT_LIST_HEAD(&intc_desc_list);555	INIT_LIST_HEAD(&intc_parent_list);556 557	for_each_matching_node_and_match(np, matches, &match) {558		if (!of_property_read_bool(np, "interrupt-controller") ||559				!of_device_is_available(np))560			continue;561 562		if (WARN(!match->data, "of_irq_init: no init function for %s\n",563			 match->compatible))564			continue;565 566		/*567		 * Here, we allocate and populate an of_intc_desc with the node568		 * pointer, interrupt-parent device_node etc.569		 */570		desc = kzalloc(sizeof(*desc), GFP_KERNEL);571		if (!desc) {572			of_node_put(np);573			goto err;574		}575 576		desc->irq_init_cb = match->data;577		desc->dev = of_node_get(np);578		/*579		 * interrupts-extended can reference multiple parent domains.580		 * Arbitrarily pick the first one; assume any other parents581		 * are the same distance away from the root irq controller.582		 */583		desc->interrupt_parent = of_parse_phandle(np, "interrupts-extended", 0);584		if (!desc->interrupt_parent)585			desc->interrupt_parent = of_irq_find_parent(np);586		if (desc->interrupt_parent == np) {587			of_node_put(desc->interrupt_parent);588			desc->interrupt_parent = NULL;589		}590		list_add_tail(&desc->list, &intc_desc_list);591	}592 593	/*594	 * The root irq controller is the one without an interrupt-parent.595	 * That one goes first, followed by the controllers that reference it,596	 * followed by the ones that reference the 2nd level controllers, etc.597	 */598	while (!list_empty(&intc_desc_list)) {599		/*600		 * Process all controllers with the current 'parent'.601		 * First pass will be looking for NULL as the parent.602		 * The assumption is that NULL parent means a root controller.603		 */604		list_for_each_entry_safe(desc, temp_desc, &intc_desc_list, list) {605			int ret;606 607			if (desc->interrupt_parent != parent)608				continue;609 610			list_del(&desc->list);611 612			of_node_set_flag(desc->dev, OF_POPULATED);613 614			pr_debug("of_irq_init: init %pOF (%p), parent %p\n",615				 desc->dev,616				 desc->dev, desc->interrupt_parent);617			ret = desc->irq_init_cb(desc->dev,618						desc->interrupt_parent);619			if (ret) {620				pr_err("%s: Failed to init %pOF (%p), parent %p\n",621				       __func__, desc->dev, desc->dev,622				       desc->interrupt_parent);623				of_node_clear_flag(desc->dev, OF_POPULATED);624				kfree(desc);625				continue;626			}627 628			/*629			 * This one is now set up; add it to the parent list so630			 * its children can get processed in a subsequent pass.631			 */632			list_add_tail(&desc->list, &intc_parent_list);633		}634 635		/* Get the next pending parent that might have children */636		desc = list_first_entry_or_null(&intc_parent_list,637						typeof(*desc), list);638		if (!desc) {639			pr_err("of_irq_init: children remain, but no parents\n");640			break;641		}642		list_del(&desc->list);643		parent = desc->dev;644		kfree(desc);645	}646 647	list_for_each_entry_safe(desc, temp_desc, &intc_parent_list, list) {648		list_del(&desc->list);649		kfree(desc);650	}651err:652	list_for_each_entry_safe(desc, temp_desc, &intc_desc_list, list) {653		list_del(&desc->list);654		of_node_put(desc->dev);655		kfree(desc);656	}657}658 659static u32 __of_msi_map_id(struct device *dev, struct device_node **np,660			    u32 id_in)661{662	struct device *parent_dev;663	u32 id_out = id_in;664 665	/*666	 * Walk up the device parent links looking for one with a667	 * "msi-map" property.668	 */669	for (parent_dev = dev; parent_dev; parent_dev = parent_dev->parent)670		if (!of_map_id(parent_dev->of_node, id_in, "msi-map",671				"msi-map-mask", np, &id_out))672			break;673	return id_out;674}675 676/**677 * of_msi_map_id - Map a MSI ID for a device.678 * @dev: device for which the mapping is to be done.679 * @msi_np: device node of the expected msi controller.680 * @id_in: unmapped MSI ID for the device.681 *682 * Walk up the device hierarchy looking for devices with a "msi-map"683 * property.  If found, apply the mapping to @id_in.684 *685 * Return: The mapped MSI ID.686 */687u32 of_msi_map_id(struct device *dev, struct device_node *msi_np, u32 id_in)688{689	return __of_msi_map_id(dev, &msi_np, id_in);690}691 692/**693 * of_msi_map_get_device_domain - Use msi-map to find the relevant MSI domain694 * @dev: device for which the mapping is to be done.695 * @id: Device ID.696 * @bus_token: Bus token697 *698 * Walk up the device hierarchy looking for devices with a "msi-map"699 * property.700 *701 * Returns: the MSI domain for this device (or NULL on failure)702 */703struct irq_domain *of_msi_map_get_device_domain(struct device *dev, u32 id,704						u32 bus_token)705{706	struct device_node *np = NULL;707 708	__of_msi_map_id(dev, &np, id);709	return irq_find_matching_host(np, bus_token);710}711 712/**713 * of_msi_get_domain - Use msi-parent to find the relevant MSI domain714 * @dev: device for which the domain is requested715 * @np: device node for @dev716 * @token: bus type for this domain717 *718 * Parse the msi-parent property and returns the corresponding MSI domain.719 *720 * Returns: the MSI domain for this device (or NULL on failure).721 */722struct irq_domain *of_msi_get_domain(struct device *dev,723				     struct device_node *np,724				     enum irq_domain_bus_token token)725{726	struct of_phandle_iterator it;727	struct irq_domain *d;728	int err;729 730	of_for_each_phandle(&it, err, np, "msi-parent", "#msi-cells", 0) {731		d = irq_find_matching_host(it.node, token);732		if (d)733			return d;734	}735 736	return NULL;737}738EXPORT_SYMBOL_GPL(of_msi_get_domain);739 740/**741 * of_msi_configure - Set the msi_domain field of a device742 * @dev: device structure to associate with an MSI irq domain743 * @np: device node for that device744 */745void of_msi_configure(struct device *dev, struct device_node *np)746{747	dev_set_msi_domain(dev,748			   of_msi_get_domain(dev, np, DOMAIN_BUS_PLATFORM_MSI));749}750EXPORT_SYMBOL_GPL(of_msi_configure);751