dm: core: Add livetree access functions
Add a basic assortment of functions to access the live device tree. These come from Linux v4.9 and are modified for U-Boot to the minimum extent possible. While these functions are now very stable in Linux, it will be possible to merge in fixes if needed. Signed-off-by: Simon Glass <sjg@chromium.org>
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				|  | @ -11,3 +11,4 @@ obj-$(CONFIG_$(SPL_)SIMPLE_BUS)	+= simple-bus.o | |||
| obj-$(CONFIG_DM)	+= dump.o | ||||
| obj-$(CONFIG_$(SPL_)REGMAP)	+= regmap.o | ||||
| obj-$(CONFIG_$(SPL_)SYSCON)	+= syscon-uclass.o | ||||
| obj-$(CONFIG_OF_LIVE) += of_access.o | ||||
|  |  | |||
|  | @ -0,0 +1,735 @@ | |||
| /*
 | ||||
|  * Originally from Linux v4.9 | ||||
|  * Paul Mackerras	August 1996. | ||||
|  * Copyright (C) 1996-2005 Paul Mackerras. | ||||
|  * | ||||
|  * Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner. | ||||
|  *   {engebret|bergner}@us.ibm.com | ||||
|  * | ||||
|  * Adapted for sparc and sparc64 by David S. Miller davem@davemloft.net | ||||
|  * | ||||
|  * Reconsolidated from arch/x/kernel/prom.c by Stephen Rothwell and | ||||
|  * Grant Likely. | ||||
|  * | ||||
|  * Modified for U-Boot | ||||
|  * Copyright (c) 2017 Google, Inc | ||||
|  * | ||||
|  * This file follows drivers/of/base.c with functions in the same order as the | ||||
|  * Linux version. | ||||
|  * | ||||
|  * SPDX-License-Identifier:	GPL-2.0+ | ||||
|  */ | ||||
| 
 | ||||
| #include <common.h> | ||||
| #include <libfdt.h> | ||||
| #include <dm/of_access.h> | ||||
| #include <linux/ctype.h> | ||||
| #include <linux/err.h> | ||||
| #include <linux/ioport.h> | ||||
| 
 | ||||
| DECLARE_GLOBAL_DATA_PTR; | ||||
| 
 | ||||
| /* list of struct alias_prop aliases */ | ||||
| LIST_HEAD(aliases_lookup); | ||||
| 
 | ||||
| /* "/aliaes" node */ | ||||
| static struct device_node *of_aliases; | ||||
| 
 | ||||
| /* "/chosen" node */ | ||||
| static struct device_node *of_chosen; | ||||
| 
 | ||||
| /* node pointed to by the stdout-path alias */ | ||||
| static struct device_node *of_stdout; | ||||
| 
 | ||||
| /* pointer to options given after the alias (separated by :) or NULL if none */ | ||||
| static const char *of_stdout_options; | ||||
| 
 | ||||
| /**
 | ||||
|  * struct alias_prop - Alias property in 'aliases' node | ||||
|  * | ||||
|  * The structure represents one alias property of 'aliases' node as | ||||
|  * an entry in aliases_lookup list. | ||||
|  * | ||||
|  * @link:	List node to link the structure in aliases_lookup list | ||||
|  * @alias:	Alias property name | ||||
|  * @np:		Pointer to device_node that the alias stands for | ||||
|  * @id:		Index value from end of alias name | ||||
|  * @stem:	Alias string without the index | ||||
|  */ | ||||
| struct alias_prop { | ||||
| 	struct list_head link; | ||||
| 	const char *alias; | ||||
| 	struct device_node *np; | ||||
| 	int id; | ||||
| 	char stem[0]; | ||||
| }; | ||||
| 
 | ||||
| int of_n_addr_cells(const struct device_node *np) | ||||
| { | ||||
| 	const __be32 *ip; | ||||
| 
 | ||||
| 	do { | ||||
| 		if (np->parent) | ||||
| 			np = np->parent; | ||||
| 		ip = of_get_property(np, "#address-cells", NULL); | ||||
| 		if (ip) | ||||
| 			return be32_to_cpup(ip); | ||||
| 	} while (np->parent); | ||||
| 
 | ||||
| 	/* No #address-cells property for the root node */ | ||||
| 	return OF_ROOT_NODE_ADDR_CELLS_DEFAULT; | ||||
| } | ||||
| 
 | ||||
| int of_n_size_cells(const struct device_node *np) | ||||
| { | ||||
| 	const __be32 *ip; | ||||
| 
 | ||||
| 	do { | ||||
| 		if (np->parent) | ||||
| 			np = np->parent; | ||||
| 		ip = of_get_property(np, "#size-cells", NULL); | ||||
| 		if (ip) | ||||
| 			return be32_to_cpup(ip); | ||||
| 	} while (np->parent); | ||||
| 
 | ||||
| 	/* No #size-cells property for the root node */ | ||||
| 	return OF_ROOT_NODE_SIZE_CELLS_DEFAULT; | ||||
| } | ||||
| 
 | ||||
| struct property *of_find_property(const struct device_node *np, | ||||
| 				  const char *name, int *lenp) | ||||
| { | ||||
| 	struct property *pp; | ||||
| 
 | ||||
| 	if (!np) | ||||
| 		return NULL; | ||||
| 
 | ||||
| 	for (pp = np->properties; pp; pp = pp->next) { | ||||
| 		if (strcmp(pp->name, name) == 0) { | ||||
| 			if (lenp) | ||||
| 				*lenp = pp->length; | ||||
| 			break; | ||||
| 		} | ||||
| 	} | ||||
| 	if (!pp && lenp) | ||||
| 		*lenp = -FDT_ERR_NOTFOUND; | ||||
| 
 | ||||
| 	return pp; | ||||
| } | ||||
| 
 | ||||
| struct device_node *of_find_all_nodes(struct device_node *prev) | ||||
| { | ||||
| 	struct device_node *np; | ||||
| 
 | ||||
| 	if (!prev) { | ||||
| 		np = gd->of_root; | ||||
| 	} else if (prev->child) { | ||||
| 		np = prev->child; | ||||
| 	} else { | ||||
| 		/*
 | ||||
| 		 * Walk back up looking for a sibling, or the end of the | ||||
| 		 * structure | ||||
| 		 */ | ||||
| 		np = prev; | ||||
| 		while (np->parent && !np->sibling) | ||||
| 			np = np->parent; | ||||
| 		np = np->sibling; /* Might be null at the end of the tree */ | ||||
| 	} | ||||
| 
 | ||||
| 	return np; | ||||
| } | ||||
| 
 | ||||
| const void *of_get_property(const struct device_node *np, const char *name, | ||||
| 			    int *lenp) | ||||
| { | ||||
| 	struct property *pp = of_find_property(np, name, lenp); | ||||
| 
 | ||||
| 	return pp ? pp->value : NULL; | ||||
| } | ||||
| 
 | ||||
| static const char *of_prop_next_string(struct property *prop, const char *cur) | ||||
| { | ||||
| 	const void *curv = cur; | ||||
| 
 | ||||
| 	if (!prop) | ||||
| 		return NULL; | ||||
| 
 | ||||
| 	if (!cur) | ||||
| 		return prop->value; | ||||
| 
 | ||||
| 	curv += strlen(cur) + 1; | ||||
| 	if (curv >= prop->value + prop->length) | ||||
| 		return NULL; | ||||
| 
 | ||||
| 	return curv; | ||||
| } | ||||
| 
 | ||||
| int of_device_is_compatible(const struct device_node *device, | ||||
| 			    const char *compat, const char *type, | ||||
| 			    const char *name) | ||||
| { | ||||
| 	struct property *prop; | ||||
| 	const char *cp; | ||||
| 	int index = 0, score = 0; | ||||
| 
 | ||||
| 	/* Compatible match has highest priority */ | ||||
| 	if (compat && compat[0]) { | ||||
| 		prop = of_find_property(device, "compatible", NULL); | ||||
| 		for (cp = of_prop_next_string(prop, NULL); cp; | ||||
| 		     cp = of_prop_next_string(prop, cp), index++) { | ||||
| 			if (of_compat_cmp(cp, compat, strlen(compat)) == 0) { | ||||
| 				score = INT_MAX/2 - (index << 2); | ||||
| 				break; | ||||
| 			} | ||||
| 		} | ||||
| 		if (!score) | ||||
| 			return 0; | ||||
| 	} | ||||
| 
 | ||||
| 	/* Matching type is better than matching name */ | ||||
| 	if (type && type[0]) { | ||||
| 		if (!device->type || of_node_cmp(type, device->type)) | ||||
| 			return 0; | ||||
| 		score += 2; | ||||
| 	} | ||||
| 
 | ||||
| 	/* Matching name is a bit better than not */ | ||||
| 	if (name && name[0]) { | ||||
| 		if (!device->name || of_node_cmp(name, device->name)) | ||||
| 			return 0; | ||||
| 		score++; | ||||
| 	} | ||||
| 
 | ||||
| 	return score; | ||||
| } | ||||
| 
 | ||||
| bool of_device_is_available(const struct device_node *device) | ||||
| { | ||||
| 	const char *status; | ||||
| 	int statlen; | ||||
| 
 | ||||
| 	if (!device) | ||||
| 		return false; | ||||
| 
 | ||||
| 	status = of_get_property(device, "status", &statlen); | ||||
| 	if (status == NULL) | ||||
| 		return true; | ||||
| 
 | ||||
| 	if (statlen > 0) { | ||||
| 		if (!strcmp(status, "okay")) | ||||
| 			return true; | ||||
| 	} | ||||
| 
 | ||||
| 	return false; | ||||
| } | ||||
| 
 | ||||
| struct device_node *of_get_parent(const struct device_node *node) | ||||
| { | ||||
| 	const struct device_node *np; | ||||
| 
 | ||||
| 	if (!node) | ||||
| 		return NULL; | ||||
| 
 | ||||
| 	np = of_node_get(node->parent); | ||||
| 
 | ||||
| 	return (struct device_node *)np; | ||||
| } | ||||
| 
 | ||||
| static struct device_node *__of_get_next_child(const struct device_node *node, | ||||
| 					       struct device_node *prev) | ||||
| { | ||||
| 	struct device_node *next; | ||||
| 
 | ||||
| 	if (!node) | ||||
| 		return NULL; | ||||
| 
 | ||||
| 	next = prev ? prev->sibling : node->child; | ||||
| 	for (; next; next = next->sibling) | ||||
| 		if (of_node_get(next)) | ||||
| 			break; | ||||
| 	of_node_put(prev); | ||||
| 	return next; | ||||
| } | ||||
| 
 | ||||
| #define __for_each_child_of_node(parent, child) \ | ||||
| 	for (child = __of_get_next_child(parent, NULL); child != NULL; \ | ||||
| 	     child = __of_get_next_child(parent, child)) | ||||
| 
 | ||||
| static struct device_node *__of_find_node_by_path(struct device_node *parent, | ||||
| 						  const char *path) | ||||
| { | ||||
| 	struct device_node *child; | ||||
| 	int len; | ||||
| 
 | ||||
| 	len = strcspn(path, "/:"); | ||||
| 	if (!len) | ||||
| 		return NULL; | ||||
| 
 | ||||
| 	__for_each_child_of_node(parent, child) { | ||||
| 		const char *name = strrchr(child->full_name, '/'); | ||||
| 
 | ||||
| 		name++; | ||||
| 		if (strncmp(path, name, len) == 0 && (strlen(name) == len)) | ||||
| 			return child; | ||||
| 	} | ||||
| 	return NULL; | ||||
| } | ||||
| 
 | ||||
| #define for_each_property_of_node(dn, pp) \ | ||||
| 	for (pp = dn->properties; pp != NULL; pp = pp->next) | ||||
| 
 | ||||
| struct device_node *of_find_node_opts_by_path(const char *path, | ||||
| 					      const char **opts) | ||||
| { | ||||
| 	struct device_node *np = NULL; | ||||
| 	struct property *pp; | ||||
| 	const char *separator = strchr(path, ':'); | ||||
| 
 | ||||
| 	if (opts) | ||||
| 		*opts = separator ? separator + 1 : NULL; | ||||
| 
 | ||||
| 	if (strcmp(path, "/") == 0) | ||||
| 		return of_node_get(gd->of_root); | ||||
| 
 | ||||
| 	/* The path could begin with an alias */ | ||||
| 	if (*path != '/') { | ||||
| 		int len; | ||||
| 		const char *p = separator; | ||||
| 
 | ||||
| 		if (!p) | ||||
| 			p = strchrnul(path, '/'); | ||||
| 		len = p - path; | ||||
| 
 | ||||
| 		/* of_aliases must not be NULL */ | ||||
| 		if (!of_aliases) | ||||
| 			return NULL; | ||||
| 
 | ||||
| 		for_each_property_of_node(of_aliases, pp) { | ||||
| 			if (strlen(pp->name) == len && !strncmp(pp->name, path, | ||||
| 								len)) { | ||||
| 				np = of_find_node_by_path(pp->value); | ||||
| 				break; | ||||
| 			} | ||||
| 		} | ||||
| 		if (!np) | ||||
| 			return NULL; | ||||
| 		path = p; | ||||
| 	} | ||||
| 
 | ||||
| 	/* Step down the tree matching path components */ | ||||
| 	if (!np) | ||||
| 		np = of_node_get(gd->of_root); | ||||
| 	while (np && *path == '/') { | ||||
| 		struct device_node *tmp = np; | ||||
| 
 | ||||
| 		path++; /* Increment past '/' delimiter */ | ||||
| 		np = __of_find_node_by_path(np, path); | ||||
| 		of_node_put(tmp); | ||||
| 		path = strchrnul(path, '/'); | ||||
| 		if (separator && separator < path) | ||||
| 			break; | ||||
| 	} | ||||
| 
 | ||||
| 	return np; | ||||
| } | ||||
| 
 | ||||
| struct device_node *of_find_compatible_node(struct device_node *from, | ||||
| 		const char *type, const char *compatible) | ||||
| { | ||||
| 	struct device_node *np; | ||||
| 
 | ||||
| 	for_each_of_allnodes_from(from, np) | ||||
| 		if (of_device_is_compatible(np, compatible, type, NULL) && | ||||
| 		    of_node_get(np)) | ||||
| 			break; | ||||
| 	of_node_put(from); | ||||
| 
 | ||||
| 	return np; | ||||
| } | ||||
| 
 | ||||
| struct device_node *of_find_node_by_phandle(phandle handle) | ||||
| { | ||||
| 	struct device_node *np; | ||||
| 
 | ||||
| 	if (!handle) | ||||
| 		return NULL; | ||||
| 
 | ||||
| 	for_each_of_allnodes(np) | ||||
| 		if (np->phandle == handle) | ||||
| 			break; | ||||
| 	(void)of_node_get(np); | ||||
| 
 | ||||
| 	return np; | ||||
| } | ||||
| 
 | ||||
| /**
 | ||||
|  * of_find_property_value_of_size() - find property of given size | ||||
|  * | ||||
|  * Search for a property in a device node and validate the requested size. | ||||
|  * | ||||
|  * @np:		device node from which the property value is to be read. | ||||
|  * @propname:	name of the property to be searched. | ||||
|  * @len:	requested length of property value | ||||
|  * | ||||
|  * @return the property value on success, -EINVAL if the property does not | ||||
|  * exist, -ENODATA if property does not have a value, and -EOVERFLOW if the | ||||
|  * property data isn't large enough. | ||||
|  */ | ||||
| static void *of_find_property_value_of_size(const struct device_node *np, | ||||
| 					    const char *propname, u32 len) | ||||
| { | ||||
| 	struct property *prop = of_find_property(np, propname, NULL); | ||||
| 
 | ||||
| 	if (!prop) | ||||
| 		return ERR_PTR(-EINVAL); | ||||
| 	if (!prop->value) | ||||
| 		return ERR_PTR(-ENODATA); | ||||
| 	if (len > prop->length) | ||||
| 		return ERR_PTR(-EOVERFLOW); | ||||
| 
 | ||||
| 	return prop->value; | ||||
| } | ||||
| 
 | ||||
| int of_read_u32(const struct device_node *np, const char *propname, u32 *outp) | ||||
| { | ||||
| 	const __be32 *val; | ||||
| 
 | ||||
| 	debug("%s: %s: ", __func__, propname); | ||||
| 	if (!np) | ||||
| 		return -EINVAL; | ||||
| 	val = of_find_property_value_of_size(np, propname, sizeof(*outp)); | ||||
| 	if (IS_ERR(val)) { | ||||
| 		debug("(not found)\n"); | ||||
| 		return PTR_ERR(val); | ||||
| 	} | ||||
| 
 | ||||
| 	*outp = be32_to_cpup(val); | ||||
| 	debug("%#x (%d)\n", *outp, *outp); | ||||
| 
 | ||||
| 	return 0; | ||||
| } | ||||
| 
 | ||||
| int of_read_u32_array(const struct device_node *np, const char *propname, | ||||
| 		      u32 *out_values, size_t sz) | ||||
| { | ||||
| 	const __be32 *val; | ||||
| 
 | ||||
| 	debug("%s: %s: ", __func__, propname); | ||||
| 	val = of_find_property_value_of_size(np, propname, | ||||
| 					     sz * sizeof(*out_values)); | ||||
| 
 | ||||
| 	if (IS_ERR(val)) | ||||
| 		return PTR_ERR(val); | ||||
| 
 | ||||
| 	debug("size %zd\n", sz); | ||||
| 	while (sz--) | ||||
| 		*out_values++ = be32_to_cpup(val++); | ||||
| 
 | ||||
| 	return 0; | ||||
| } | ||||
| 
 | ||||
| int of_property_match_string(const struct device_node *np, const char *propname, | ||||
| 			     const char *string) | ||||
| { | ||||
| 	const struct property *prop = of_find_property(np, propname, NULL); | ||||
| 	size_t l; | ||||
| 	int i; | ||||
| 	const char *p, *end; | ||||
| 
 | ||||
| 	if (!prop) | ||||
| 		return -EINVAL; | ||||
| 	if (!prop->value) | ||||
| 		return -ENODATA; | ||||
| 
 | ||||
| 	p = prop->value; | ||||
| 	end = p + prop->length; | ||||
| 
 | ||||
| 	for (i = 0; p < end; i++, p += l) { | ||||
| 		l = strnlen(p, end - p) + 1; | ||||
| 		if (p + l > end) | ||||
| 			return -EILSEQ; | ||||
| 		debug("comparing %s with %s\n", string, p); | ||||
| 		if (strcmp(string, p) == 0) | ||||
| 			return i; /* Found it; return index */ | ||||
| 	} | ||||
| 	return -ENODATA; | ||||
| } | ||||
| 
 | ||||
| /**
 | ||||
|  * of_property_read_string_helper() - Utility helper for parsing string properties | ||||
|  * @np:		device node from which the property value is to be read. | ||||
|  * @propname:	name of the property to be searched. | ||||
|  * @out_strs:	output array of string pointers. | ||||
|  * @sz:		number of array elements to read. | ||||
|  * @skip:	Number of strings to skip over at beginning of list. | ||||
|  * | ||||
|  * Don't call this function directly. It is a utility helper for the | ||||
|  * of_property_read_string*() family of functions. | ||||
|  */ | ||||
| int of_property_read_string_helper(const struct device_node *np, | ||||
| 				   const char *propname, const char **out_strs, | ||||
| 				   size_t sz, int skip) | ||||
| { | ||||
| 	const struct property *prop = of_find_property(np, propname, NULL); | ||||
| 	int l = 0, i = 0; | ||||
| 	const char *p, *end; | ||||
| 
 | ||||
| 	if (!prop) | ||||
| 		return -EINVAL; | ||||
| 	if (!prop->value) | ||||
| 		return -ENODATA; | ||||
| 	p = prop->value; | ||||
| 	end = p + prop->length; | ||||
| 
 | ||||
| 	for (i = 0; p < end && (!out_strs || i < skip + sz); i++, p += l) { | ||||
| 		l = strnlen(p, end - p) + 1; | ||||
| 		if (p + l > end) | ||||
| 			return -EILSEQ; | ||||
| 		if (out_strs && i >= skip) | ||||
| 			*out_strs++ = p; | ||||
| 	} | ||||
| 	i -= skip; | ||||
| 	return i <= 0 ? -ENODATA : i; | ||||
| } | ||||
| 
 | ||||
| static int __of_parse_phandle_with_args(const struct device_node *np, | ||||
| 					const char *list_name, | ||||
| 					const char *cells_name, | ||||
| 					int cell_count, int index, | ||||
| 					struct of_phandle_args *out_args) | ||||
| { | ||||
| 	const __be32 *list, *list_end; | ||||
| 	int rc = 0, cur_index = 0; | ||||
| 	uint32_t count = 0; | ||||
| 	struct device_node *node = NULL; | ||||
| 	phandle phandle; | ||||
| 	int size; | ||||
| 
 | ||||
| 	/* Retrieve the phandle list property */ | ||||
| 	list = of_get_property(np, list_name, &size); | ||||
| 	if (!list) | ||||
| 		return -ENOENT; | ||||
| 	list_end = list + size / sizeof(*list); | ||||
| 
 | ||||
| 	/* Loop over the phandles until all the requested entry is found */ | ||||
| 	while (list < list_end) { | ||||
| 		rc = -EINVAL; | ||||
| 		count = 0; | ||||
| 
 | ||||
| 		/*
 | ||||
| 		 * If phandle is 0, then it is an empty entry with no | ||||
| 		 * arguments.  Skip forward to the next entry. | ||||
| 		 */ | ||||
| 		phandle = be32_to_cpup(list++); | ||||
| 		if (phandle) { | ||||
| 			/*
 | ||||
| 			 * Find the provider node and parse the #*-cells | ||||
| 			 * property to determine the argument length. | ||||
| 			 * | ||||
| 			 * This is not needed if the cell count is hard-coded | ||||
| 			 * (i.e. cells_name not set, but cell_count is set), | ||||
| 			 * except when we're going to return the found node | ||||
| 			 * below. | ||||
| 			 */ | ||||
| 			if (cells_name || cur_index == index) { | ||||
| 				node = of_find_node_by_phandle(phandle); | ||||
| 				if (!node) { | ||||
| 					debug("%s: could not find phandle\n", | ||||
| 					      np->full_name); | ||||
| 					goto err; | ||||
| 				} | ||||
| 			} | ||||
| 
 | ||||
| 			if (cells_name) { | ||||
| 				if (of_read_u32(node, cells_name, &count)) { | ||||
| 					debug("%s: could not get %s for %s\n", | ||||
| 					      np->full_name, cells_name, | ||||
| 					      node->full_name); | ||||
| 					goto err; | ||||
| 				} | ||||
| 			} else { | ||||
| 				count = cell_count; | ||||
| 			} | ||||
| 
 | ||||
| 			/*
 | ||||
| 			 * Make sure that the arguments actually fit in the | ||||
| 			 * remaining property data length | ||||
| 			 */ | ||||
| 			if (list + count > list_end) { | ||||
| 				debug("%s: arguments longer than property\n", | ||||
| 				      np->full_name); | ||||
| 				goto err; | ||||
| 			} | ||||
| 		} | ||||
| 
 | ||||
| 		/*
 | ||||
| 		 * All of the error cases above bail out of the loop, so at | ||||
| 		 * this point, the parsing is successful. If the requested | ||||
| 		 * index matches, then fill the out_args structure and return, | ||||
| 		 * or return -ENOENT for an empty entry. | ||||
| 		 */ | ||||
| 		rc = -ENOENT; | ||||
| 		if (cur_index == index) { | ||||
| 			if (!phandle) | ||||
| 				goto err; | ||||
| 
 | ||||
| 			if (out_args) { | ||||
| 				int i; | ||||
| 				if (WARN_ON(count > OF_MAX_PHANDLE_ARGS)) | ||||
| 					count = OF_MAX_PHANDLE_ARGS; | ||||
| 				out_args->np = node; | ||||
| 				out_args->args_count = count; | ||||
| 				for (i = 0; i < count; i++) | ||||
| 					out_args->args[i] = | ||||
| 							be32_to_cpup(list++); | ||||
| 			} else { | ||||
| 				of_node_put(node); | ||||
| 			} | ||||
| 
 | ||||
| 			/* Found it! return success */ | ||||
| 			return 0; | ||||
| 		} | ||||
| 
 | ||||
| 		of_node_put(node); | ||||
| 		node = NULL; | ||||
| 		list += count; | ||||
| 		cur_index++; | ||||
| 	} | ||||
| 
 | ||||
| 	/*
 | ||||
| 	 * Unlock node before returning result; will be one of: | ||||
| 	 * -ENOENT : index is for empty phandle | ||||
| 	 * -EINVAL : parsing error on data | ||||
| 	 * [1..n]  : Number of phandle (count mode; when index = -1) | ||||
| 	 */ | ||||
| 	rc = index < 0 ? cur_index : -ENOENT; | ||||
|  err: | ||||
| 	if (node) | ||||
| 		of_node_put(node); | ||||
| 	return rc; | ||||
| } | ||||
| 
 | ||||
| struct device_node *of_parse_phandle(const struct device_node *np, | ||||
| 				     const char *phandle_name, int index) | ||||
| { | ||||
| 	struct of_phandle_args args; | ||||
| 
 | ||||
| 	if (index < 0) | ||||
| 		return NULL; | ||||
| 
 | ||||
| 	if (__of_parse_phandle_with_args(np, phandle_name, NULL, 0, index, | ||||
| 					 &args)) | ||||
| 		return NULL; | ||||
| 
 | ||||
| 	return args.np; | ||||
| } | ||||
| 
 | ||||
| int of_parse_phandle_with_args(const struct device_node *np, | ||||
| 			       const char *list_name, const char *cells_name, | ||||
| 			       int index, struct of_phandle_args *out_args) | ||||
| { | ||||
| 	if (index < 0) | ||||
| 		return -EINVAL; | ||||
| 
 | ||||
| 	return __of_parse_phandle_with_args(np, list_name, cells_name, 0, | ||||
| 					    index, out_args); | ||||
| } | ||||
| 
 | ||||
| static void of_alias_add(struct alias_prop *ap, struct device_node *np, | ||||
| 			 int id, const char *stem, int stem_len) | ||||
| { | ||||
| 	ap->np = np; | ||||
| 	ap->id = id; | ||||
| 	strncpy(ap->stem, stem, stem_len); | ||||
| 	ap->stem[stem_len] = 0; | ||||
| 	list_add_tail(&ap->link, &aliases_lookup); | ||||
| 	debug("adding DT alias:%s: stem=%s id=%i node=%s\n", | ||||
| 	      ap->alias, ap->stem, ap->id, of_node_full_name(np)); | ||||
| } | ||||
| 
 | ||||
| int of_alias_scan(void) | ||||
| { | ||||
| 	struct property *pp; | ||||
| 
 | ||||
| 	of_aliases = of_find_node_by_path("/aliases"); | ||||
| 	of_chosen = of_find_node_by_path("/chosen"); | ||||
| 	if (of_chosen == NULL) | ||||
| 		of_chosen = of_find_node_by_path("/chosen@0"); | ||||
| 
 | ||||
| 	if (of_chosen) { | ||||
| 		const char *name; | ||||
| 
 | ||||
| 		name = of_get_property(of_chosen, "stdout-path", NULL); | ||||
| 		if (name) | ||||
| 			of_stdout = of_find_node_opts_by_path(name, | ||||
| 							&of_stdout_options); | ||||
| 	} | ||||
| 
 | ||||
| 	if (!of_aliases) | ||||
| 		return 0; | ||||
| 
 | ||||
| 	for_each_property_of_node(of_aliases, pp) { | ||||
| 		const char *start = pp->name; | ||||
| 		const char *end = start + strlen(start); | ||||
| 		struct device_node *np; | ||||
| 		struct alias_prop *ap; | ||||
| 		ulong id; | ||||
| 		int len; | ||||
| 
 | ||||
| 		/* Skip those we do not want to proceed */ | ||||
| 		if (!strcmp(pp->name, "name") || | ||||
| 		    !strcmp(pp->name, "phandle") || | ||||
| 		    !strcmp(pp->name, "linux,phandle")) | ||||
| 			continue; | ||||
| 
 | ||||
| 		np = of_find_node_by_path(pp->value); | ||||
| 		if (!np) | ||||
| 			continue; | ||||
| 
 | ||||
| 		/*
 | ||||
| 		 * walk the alias backwards to extract the id and work out | ||||
| 		 * the 'stem' string | ||||
| 		 */ | ||||
| 		while (isdigit(*(end-1)) && end > start) | ||||
| 			end--; | ||||
| 		len = end - start; | ||||
| 
 | ||||
| 		if (strict_strtoul(end, 10, &id) < 0) | ||||
| 			continue; | ||||
| 
 | ||||
| 		/* Allocate an alias_prop with enough space for the stem */ | ||||
| 		ap = malloc(sizeof(*ap) + len + 1); | ||||
| 		if (!ap) | ||||
| 			return -ENOMEM; | ||||
| 		memset(ap, 0, sizeof(*ap) + len + 1); | ||||
| 		ap->alias = start; | ||||
| 		of_alias_add(ap, np, id, start, len); | ||||
| 	} | ||||
| 
 | ||||
| 	return 0; | ||||
| } | ||||
| 
 | ||||
| int of_alias_get_id(const struct device_node *np, const char *stem) | ||||
| { | ||||
| 	struct alias_prop *app; | ||||
| 	int id = -ENODEV; | ||||
| 
 | ||||
| 	mutex_lock(&of_mutex); | ||||
| 	list_for_each_entry(app, &aliases_lookup, link) { | ||||
| 		if (strcmp(app->stem, stem) != 0) | ||||
| 			continue; | ||||
| 
 | ||||
| 		if (np == app->np) { | ||||
| 			id = app->id; | ||||
| 			break; | ||||
| 		} | ||||
| 	} | ||||
| 	mutex_unlock(&of_mutex); | ||||
| 
 | ||||
| 	return id; | ||||
| } | ||||
| 
 | ||||
| struct device_node *of_get_stdout(void) | ||||
| { | ||||
| 	return of_stdout; | ||||
| } | ||||
|  | @ -0,0 +1,347 @@ | |||
| /*
 | ||||
|  * Originally from Linux v4.9 | ||||
|  * Copyright (C) 1996-2005 Paul Mackerras. | ||||
|  * | ||||
|  * Updates for PPC64 by Peter Bergner & David Engebretsen, IBM Corp. | ||||
|  * Updates for SPARC64 by David S. Miller | ||||
|  * Derived from PowerPC and Sparc prom.h files by Stephen Rothwell, IBM Corp. | ||||
|  * | ||||
|  * Copyright (c) 2017 Google, Inc | ||||
|  * Written by Simon Glass <sjg@chromium.org> | ||||
|  * | ||||
|  * Modified for U-Boot | ||||
|  * Copyright (c) 2017 Google, Inc | ||||
|  * | ||||
|  * SPDX-License-Identifier:	GPL-2.0+ | ||||
|  */ | ||||
| 
 | ||||
| #ifndef _DM_OF_ACCESS_H | ||||
| #define _DM_OF_ACCESS_H | ||||
| 
 | ||||
| #include <dm/of.h> | ||||
| 
 | ||||
| /**
 | ||||
|  * of_find_all_nodes - Get next node in global list | ||||
|  * @prev:	Previous node or NULL to start iteration | ||||
|  *		of_node_put() will be called on it | ||||
|  * | ||||
|  * Returns a node pointer with refcount incremented, use | ||||
|  * of_node_put() on it when done. | ||||
|  */ | ||||
| struct device_node *of_find_all_nodes(struct device_node *prev); | ||||
| 
 | ||||
| #define for_each_of_allnodes_from(from, dn) \ | ||||
| 	for (dn = of_find_all_nodes(from); dn; dn = of_find_all_nodes(dn)) | ||||
| #define for_each_of_allnodes(dn) for_each_of_allnodes_from(NULL, dn) | ||||
| 
 | ||||
| /* Dummy functions to mirror Linux. These are not used in U-Boot */ | ||||
| #define of_node_get(x) (x) | ||||
| static inline void of_node_put(const struct device_node *np) { } | ||||
| 
 | ||||
| /**
 | ||||
|  * of_n_addr_cells() - Get the number of address cells for a node | ||||
|  * | ||||
|  * This walks back up the tree to find the closest #address-cells property | ||||
|  * which controls the given node. | ||||
|  * | ||||
|  * @np: Node pointer to check | ||||
|  * @return number of address cells this node uses | ||||
|  */ | ||||
| int of_n_addr_cells(const struct device_node *np); | ||||
| 
 | ||||
| /**
 | ||||
|  * of_n_size_cells() - Get the number of size cells for a node | ||||
|  * | ||||
|  * This walks back up the tree to find the closest #size-cells property | ||||
|  * which controls the given node. | ||||
|  * | ||||
|  * @np: Node pointer to check | ||||
|  * @return number of size cells this node uses | ||||
|  */ | ||||
| int of_n_size_cells(const struct device_node *np); | ||||
| 
 | ||||
| /**
 | ||||
|  * of_find_property() - find a property in a node | ||||
|  * | ||||
|  * @np: Pointer to device node holding property | ||||
|  * @name: Name of property | ||||
|  * @lenp: If non-NULL, returns length of property | ||||
|  * @return pointer to property, or NULL if not found | ||||
|  */ | ||||
| struct property *of_find_property(const struct device_node *np, | ||||
| 				  const char *name, int *lenp); | ||||
| 
 | ||||
| /**
 | ||||
|  * of_get_property() - get a property value | ||||
|  * | ||||
|  * Find a property with a given name for a given node and return the value. | ||||
|  * | ||||
|  * @np: Pointer to device node holding property | ||||
|  * @name: Name of property | ||||
|  * @lenp: If non-NULL, returns length of property | ||||
|  * @return pointer to property value, or NULL if not found | ||||
|  */ | ||||
| const void *of_get_property(const struct device_node *np, const char *name, | ||||
| 			    int *lenp); | ||||
| 
 | ||||
| /**
 | ||||
|  * of_device_is_compatible() - Check if the node matches given constraints | ||||
|  * @device: pointer to node | ||||
|  * @compat: required compatible string, NULL or "" for any match | ||||
|  * @type: required device_type value, NULL or "" for any match | ||||
|  * @name: required node name, NULL or "" for any match | ||||
|  * | ||||
|  * Checks if the given @compat, @type and @name strings match the | ||||
|  * properties of the given @device. A constraints can be skipped by | ||||
|  * passing NULL or an empty string as the constraint. | ||||
|  * | ||||
|  * @return 0 for no match, and a positive integer on match. The return | ||||
|  * value is a relative score with larger values indicating better | ||||
|  * matches. The score is weighted for the most specific compatible value | ||||
|  * to get the highest score. Matching type is next, followed by matching | ||||
|  * name. Practically speaking, this results in the following priority | ||||
|  * order for matches: | ||||
|  * | ||||
|  * 1. specific compatible && type && name | ||||
|  * 2. specific compatible && type | ||||
|  * 3. specific compatible && name | ||||
|  * 4. specific compatible | ||||
|  * 5. general compatible && type && name | ||||
|  * 6. general compatible && type | ||||
|  * 7. general compatible && name | ||||
|  * 8. general compatible | ||||
|  * 9. type && name | ||||
|  * 10. type | ||||
|  * 11. name | ||||
|  */ | ||||
| int of_device_is_compatible(const struct device_node *np, const char *compat, | ||||
| 			    const char *type, const char *name); | ||||
| 
 | ||||
| /**
 | ||||
|  * of_device_is_available() - check if a device is available for use | ||||
|  * | ||||
|  * @device: Node to check for availability | ||||
|  * | ||||
|  * @return true if the status property is absent or set to "okay", false | ||||
|  * otherwise | ||||
|  */ | ||||
| bool of_device_is_available(const struct device_node *np); | ||||
| 
 | ||||
| /**
 | ||||
|  * of_get_parent() - Get a node's parent, if any | ||||
|  * | ||||
|  * @node: Node to check | ||||
|  * @eturns a node pointer, or NULL if none | ||||
|  */ | ||||
| struct device_node *of_get_parent(const struct device_node *np); | ||||
| 
 | ||||
| /**
 | ||||
|  * of_find_node_opts_by_path() - Find a node matching a full OF path | ||||
|  * | ||||
|  * @path: Either the full path to match, or if the path does not start with | ||||
|  *	'/', the name of a property of the /aliases node (an alias). In the | ||||
|  *	case of an alias, the node matching the alias' value will be returned. | ||||
|  * @opts: Address of a pointer into which to store the start of an options | ||||
|  *	string appended to the end of the path with a ':' separator. Can be NULL | ||||
|  * | ||||
|  * Valid paths: | ||||
|  *	/foo/bar	Full path | ||||
|  *	foo		Valid alias | ||||
|  *	foo/bar		Valid alias + relative path | ||||
|  * | ||||
|  * @return a node pointer or NULL if not found | ||||
|  */ | ||||
| struct device_node *of_find_node_opts_by_path(const char *path, | ||||
| 					      const char **opts); | ||||
| 
 | ||||
| static inline struct device_node *of_find_node_by_path(const char *path) | ||||
| { | ||||
| 	return of_find_node_opts_by_path(path, NULL); | ||||
| } | ||||
| 
 | ||||
| /**
 | ||||
|  * of_find_compatible_node() - find a node based on its compatible string | ||||
|  * | ||||
|  * Find a node based on type and one of the tokens in its "compatible" property | ||||
|  * @from: Node to start searching from or NULL. the node you pass will not be | ||||
|  *	searched, only the next one will; typically, you pass what the previous | ||||
|  *	call returned. | ||||
|  * @type: The type string to match "device_type" or NULL to ignore | ||||
|  * @compatible:	The string to match to one of the tokens in the device | ||||
|  *	"compatible" list. | ||||
|  * @return node pointer or NULL if not found | ||||
|  */ | ||||
| struct device_node *of_find_compatible_node(struct device_node *from, | ||||
| 				const char *type, const char *compatible); | ||||
| 
 | ||||
| /**
 | ||||
|  * of_find_node_by_phandle() - Find a node given a phandle | ||||
|  * | ||||
|  * @handle:	phandle of the node to find | ||||
|  * | ||||
|  * @return node pointer, or NULL if not found | ||||
|  */ | ||||
| struct device_node *of_find_node_by_phandle(phandle handle); | ||||
| 
 | ||||
| /**
 | ||||
|  * of_read_u32() - Find and read a 32-bit integer from a property | ||||
|  * | ||||
|  * Search for a property in a device node and read a 32-bit value from | ||||
|  * it. | ||||
|  * | ||||
|  * @np:		device node from which the property value is to be read. | ||||
|  * @propname:	name of the property to be searched. | ||||
|  * @outp:	pointer to return value, modified only if return value is 0. | ||||
|  * | ||||
|  * @return 0 on success, -EINVAL if the property does not exist, | ||||
|  * -ENODATA if property does not have a value, and -EOVERFLOW if the | ||||
|  * property data isn't large enough. | ||||
|  */ | ||||
| int of_read_u32(const struct device_node *np, const char *propname, u32 *outp); | ||||
| 
 | ||||
| /**
 | ||||
|  * of_read_u32_array() - Find and read an array of 32 bit integers | ||||
|  * | ||||
|  * Search for a property in a device node and read 32-bit value(s) from | ||||
|  * it. | ||||
|  * | ||||
|  * @np:		device node from which the property value is to be read. | ||||
|  * @propname:	name of the property to be searched. | ||||
|  * @out_values:	pointer to return value, modified only if return value is 0. | ||||
|  * @sz:		number of array elements to read | ||||
|  * @return 0 on success, -EINVAL if the property does not exist, -ENODATA | ||||
|  * if property does not have a value, and -EOVERFLOW is longer than sz. | ||||
|  */ | ||||
| int of_read_u32_array(const struct device_node *np, const char *propname, | ||||
| 		      u32 *out_values, size_t sz); | ||||
| 
 | ||||
| /**
 | ||||
|  * of_property_match_string() - Find string in a list and return index | ||||
|  * | ||||
|  * This function searches a string list property and returns the index | ||||
|  * of a specific string value. | ||||
|  * | ||||
|  * @np: pointer to node containing string list property | ||||
|  * @propname: string list property name | ||||
|  * @string: pointer to string to search for in string list | ||||
|  * @return 0 on success, -EINVAL if the property does not exist, -ENODATA | ||||
|  * if property does not have a value, and -EOVERFLOW is longer than sz. | ||||
|  */ | ||||
| int of_property_match_string(const struct device_node *np, const char *propname, | ||||
| 			     const char *string); | ||||
| 
 | ||||
| int of_property_read_string_helper(const struct device_node *np, | ||||
| 				   const char *propname, const char **out_strs, | ||||
| 				   size_t sz, int index); | ||||
| 
 | ||||
| /**
 | ||||
|  * of_property_read_string_index() - Find and read a string from a multiple | ||||
|  * strings property. | ||||
|  * @np:		device node from which the property value is to be read. | ||||
|  * @propname:	name of the property to be searched. | ||||
|  * @index:	index of the string in the list of strings | ||||
|  * @out_string:	pointer to null terminated return string, modified only if | ||||
|  *		return value is 0. | ||||
|  * | ||||
|  * Search for a property in a device tree node and retrieve a null | ||||
|  * terminated string value (pointer to data, not a copy) in the list of strings | ||||
|  * contained in that property. | ||||
|  * Returns 0 on success, -EINVAL if the property does not exist, -ENODATA if | ||||
|  * property does not have a value, and -EILSEQ if the string is not | ||||
|  * null-terminated within the length of the property data. | ||||
|  * | ||||
|  * The out_string pointer is modified only if a valid string can be decoded. | ||||
|  */ | ||||
| static inline int of_property_read_string_index(const struct device_node *np, | ||||
| 						const char *propname, | ||||
| 						int index, const char **output) | ||||
| { | ||||
| 	int rc = of_property_read_string_helper(np, propname, output, 1, index); | ||||
| 	return rc < 0 ? rc : 0; | ||||
| } | ||||
| 
 | ||||
| /**
 | ||||
|  * of_parse_phandle - Resolve a phandle property to a device_node pointer | ||||
|  * @np: Pointer to device node holding phandle property | ||||
|  * @phandle_name: Name of property holding a phandle value | ||||
|  * @index: For properties holding a table of phandles, this is the index into | ||||
|  *         the table | ||||
|  * | ||||
|  * Returns the device_node pointer with refcount incremented.  Use | ||||
|  * of_node_put() on it when done. | ||||
|  */ | ||||
| struct device_node *of_parse_phandle(const struct device_node *np, | ||||
| 				     const char *phandle_name, int index); | ||||
| 
 | ||||
| /**
 | ||||
|  * of_parse_phandle_with_args() - Find a node pointed by phandle in a list | ||||
|  * | ||||
|  * @np:		pointer to a device tree node containing a list | ||||
|  * @list_name:	property name that contains a list | ||||
|  * @cells_name:	property name that specifies phandles' arguments count | ||||
|  * @index:	index of a phandle to parse out | ||||
|  * @out_args:	optional pointer to output arguments structure (will be filled) | ||||
|  * @return 0 on success (with @out_args filled out if not NULL), -ENOENT if | ||||
|  *	@list_name does not exist, -EINVAL if a phandle was not found, | ||||
|  *	@cells_name could not be found, the arguments were truncated or there | ||||
|  *	were too many arguments. | ||||
|  * | ||||
|  * This function is useful to parse lists of phandles and their arguments. | ||||
|  * Returns 0 on success and fills out_args, on error returns appropriate | ||||
|  * errno value. | ||||
|  * | ||||
|  * Caller is responsible to call of_node_put() on the returned out_args->np | ||||
|  * pointer. | ||||
|  * | ||||
|  * Example: | ||||
|  * | ||||
|  * phandle1: node1 { | ||||
|  *	#list-cells = <2>; | ||||
|  * } | ||||
|  * | ||||
|  * phandle2: node2 { | ||||
|  *	#list-cells = <1>; | ||||
|  * } | ||||
|  * | ||||
|  * node3 { | ||||
|  *	list = <&phandle1 1 2 &phandle2 3>; | ||||
|  * } | ||||
|  * | ||||
|  * To get a device_node of the `node2' node you may call this: | ||||
|  * of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args); | ||||
|  */ | ||||
| int of_parse_phandle_with_args(const struct device_node *np, | ||||
| 			       const char *list_name, const char *cells_name, | ||||
| 			       int index, struct of_phandle_args *out_args); | ||||
| 
 | ||||
| /**
 | ||||
|  * of_alias_scan() - Scan all properties of the 'aliases' node | ||||
|  * | ||||
|  * The function scans all the properties of the 'aliases' node and populates | ||||
|  * the lookup table with the properties.  It returns the number of alias | ||||
|  * properties found, or an error code in case of failure. | ||||
|  * | ||||
|  * @return 9 if OK, -ENOMEM if not enough memory | ||||
|  */ | ||||
| int of_alias_scan(void); | ||||
| 
 | ||||
| /**
 | ||||
|  * of_alias_get_id - Get alias id for the given device_node | ||||
|  * | ||||
|  * Travels the lookup table to get the alias id for the given device_node and | ||||
|  * alias stem. | ||||
|  * | ||||
|  * @np:		Pointer to the given device_node | ||||
|  * @stem:	Alias stem of the given device_node | ||||
|  * @return alias ID, if found, else -ENODEV | ||||
|  */ | ||||
| int of_alias_get_id(const struct device_node *np, const char *stem); | ||||
| 
 | ||||
| /**
 | ||||
|  * of_get_stdout() - Get node to use for stdout | ||||
|  * | ||||
|  * @return node referred to by stdout-path alias, or NULL if none | ||||
|  */ | ||||
| struct device_node *of_get_stdout(void); | ||||
| 
 | ||||
| #endif | ||||
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		Reference in New Issue