1 /* SPDX-License-Identifier: GPL-2.0+ */
3 * Originally from Linux v4.9
4 * Copyright (C) 1996-2005 Paul Mackerras.
6 * Updates for PPC64 by Peter Bergner & David Engebretsen, IBM Corp.
7 * Updates for SPARC64 by David S. Miller
8 * Derived from PowerPC and Sparc prom.h files by Stephen Rothwell, IBM Corp.
10 * Copyright (c) 2017 Google, Inc
11 * Written by Simon Glass <sjg@chromium.org>
14 * Copyright (c) 2017 Google, Inc
17 #ifndef _DM_OF_ACCESS_H
18 #define _DM_OF_ACCESS_H
23 * of_find_all_nodes - Get next node in global list
24 * @prev: Previous node or NULL to start iteration
25 * of_node_put() will be called on it
27 * Returns a node pointer with refcount incremented, use
28 * of_node_put() on it when done.
30 struct device_node *of_find_all_nodes(struct device_node *prev);
32 #define for_each_of_allnodes_from(from, dn) \
33 for (dn = of_find_all_nodes(from); dn; dn = of_find_all_nodes(dn))
34 #define for_each_of_allnodes(dn) for_each_of_allnodes_from(NULL, dn)
36 /* Dummy functions to mirror Linux. These are not used in U-Boot */
37 #define of_node_get(x) (x)
38 static inline void of_node_put(const struct device_node *np) { }
41 * of_n_addr_cells() - Get the number of address cells for a node
43 * This walks back up the tree to find the closest #address-cells property
44 * which controls the given node.
46 * @np: Node pointer to check
47 * @return number of address cells this node uses
49 int of_n_addr_cells(const struct device_node *np);
52 * of_n_size_cells() - Get the number of size cells for a node
54 * This walks back up the tree to find the closest #size-cells property
55 * which controls the given node.
57 * @np: Node pointer to check
58 * @return number of size cells this node uses
60 int of_n_size_cells(const struct device_node *np);
63 * of_simple_addr_cells() - Get the address cells property in a node
65 * This function matches fdt_address_cells().
67 * @np: Node pointer to check
68 * @return value of #address-cells property in this node, or 2 if none
70 int of_simple_addr_cells(const struct device_node *np);
73 * of_simple_size_cells() - Get the size cells property in a node
75 * This function matches fdt_size_cells().
77 * @np: Node pointer to check
78 * @return value of #size-cells property in this node, or 2 if none
80 int of_simple_size_cells(const struct device_node *np);
83 * of_find_property() - find a property in a node
85 * @np: Pointer to device node holding property
86 * @name: Name of property
87 * @lenp: If non-NULL, returns length of property
88 * @return pointer to property, or NULL if not found
90 struct property *of_find_property(const struct device_node *np,
91 const char *name, int *lenp);
94 * of_get_property() - get a property value
96 * Find a property with a given name for a given node and return the value.
98 * @np: Pointer to device node holding property
99 * @name: Name of property
100 * @lenp: If non-NULL, returns length of property
101 * @return pointer to property value, or NULL if not found
103 const void *of_get_property(const struct device_node *np, const char *name,
107 * of_device_is_compatible() - Check if the node matches given constraints
108 * @device: pointer to node
109 * @compat: required compatible string, NULL or "" for any match
110 * @type: required device_type value, NULL or "" for any match
111 * @name: required node name, NULL or "" for any match
113 * Checks if the given @compat, @type and @name strings match the
114 * properties of the given @device. A constraints can be skipped by
115 * passing NULL or an empty string as the constraint.
117 * @return 0 for no match, and a positive integer on match. The return
118 * value is a relative score with larger values indicating better
119 * matches. The score is weighted for the most specific compatible value
120 * to get the highest score. Matching type is next, followed by matching
121 * name. Practically speaking, this results in the following priority
124 * 1. specific compatible && type && name
125 * 2. specific compatible && type
126 * 3. specific compatible && name
127 * 4. specific compatible
128 * 5. general compatible && type && name
129 * 6. general compatible && type
130 * 7. general compatible && name
131 * 8. general compatible
136 int of_device_is_compatible(const struct device_node *np, const char *compat,
137 const char *type, const char *name);
140 * of_device_is_available() - check if a device is available for use
142 * @device: Node to check for availability
144 * @return true if the status property is absent or set to "okay", false
147 bool of_device_is_available(const struct device_node *np);
150 * of_get_parent() - Get a node's parent, if any
152 * @node: Node to check
153 * @eturns a node pointer, or NULL if none
155 struct device_node *of_get_parent(const struct device_node *np);
158 * of_find_node_opts_by_path() - Find a node matching a full OF path
160 * @path: Either the full path to match, or if the path does not start with
161 * '/', the name of a property of the /aliases node (an alias). In the
162 * case of an alias, the node matching the alias' value will be returned.
163 * @opts: Address of a pointer into which to store the start of an options
164 * string appended to the end of the path with a ':' separator. Can be NULL
169 * foo/bar Valid alias + relative path
171 * @return a node pointer or NULL if not found
173 struct device_node *of_find_node_opts_by_path(const char *path,
176 static inline struct device_node *of_find_node_by_path(const char *path)
178 return of_find_node_opts_by_path(path, NULL);
182 * of_find_compatible_node() - find a node based on its compatible string
184 * Find a node based on type and one of the tokens in its "compatible" property
185 * @from: Node to start searching from or NULL. the node you pass will not be
186 * searched, only the next one will; typically, you pass what the previous
188 * @type: The type string to match "device_type" or NULL to ignore
189 * @compatible: The string to match to one of the tokens in the device
191 * @return node pointer or NULL if not found
193 struct device_node *of_find_compatible_node(struct device_node *from,
194 const char *type, const char *compatible);
197 * of_find_node_by_prop_value() - find a node with a given property value
199 * Find a node based on a property value.
200 * @from: Node to start searching from or NULL. the node you pass will not be
201 * searched, only the next one will; typically, you pass what the previous
203 * @propname: property name to check
204 * @propval: property value to search for
205 * @proplen: length of the value in propval
206 * @return node pointer or NULL if not found
208 struct device_node *of_find_node_by_prop_value(struct device_node *from,
209 const char *propname,
213 * of_find_node_by_phandle() - Find a node given a phandle
215 * @handle: phandle of the node to find
217 * @return node pointer, or NULL if not found
219 struct device_node *of_find_node_by_phandle(phandle handle);
222 * of_read_u32() - Find and read a 32-bit integer from a property
224 * Search for a property in a device node and read a 32-bit value from
227 * @np: device node from which the property value is to be read.
228 * @propname: name of the property to be searched.
229 * @outp: pointer to return value, modified only if return value is 0.
231 * @return 0 on success, -EINVAL if the property does not exist,
232 * -ENODATA if property does not have a value, and -EOVERFLOW if the
233 * property data isn't large enough.
235 int of_read_u32(const struct device_node *np, const char *propname, u32 *outp);
238 * of_read_u64() - Find and read a 64-bit integer from a property
240 * Search for a property in a device node and read a 64-bit value from
243 * @np: device node from which the property value is to be read.
244 * @propname: name of the property to be searched.
245 * @outp: pointer to return value, modified only if return value is 0.
247 * @return 0 on success, -EINVAL if the property does not exist,
248 * -ENODATA if property does not have a value, and -EOVERFLOW if the
249 * property data isn't large enough.
251 int of_read_u64(const struct device_node *np, const char *propname, u64 *outp);
254 * of_read_u32_array() - Find and read an array of 32 bit integers
256 * Search for a property in a device node and read 32-bit value(s) from
259 * @np: device node from which the property value is to be read.
260 * @propname: name of the property to be searched.
261 * @out_values: pointer to return value, modified only if return value is 0.
262 * @sz: number of array elements to read
263 * @return 0 on success, -EINVAL if the property does not exist, -ENODATA
264 * if property does not have a value, and -EOVERFLOW is longer than sz.
266 int of_read_u32_array(const struct device_node *np, const char *propname,
267 u32 *out_values, size_t sz);
270 * of_property_match_string() - Find string in a list and return index
272 * This function searches a string list property and returns the index
273 * of a specific string value.
275 * @np: pointer to node containing string list property
276 * @propname: string list property name
277 * @string: pointer to string to search for in string list
278 * @return 0 on success, -EINVAL if the property does not exist, -ENODATA
279 * if property does not have a value, and -EOVERFLOW is longer than sz.
281 int of_property_match_string(const struct device_node *np, const char *propname,
284 int of_property_read_string_helper(const struct device_node *np,
285 const char *propname, const char **out_strs,
286 size_t sz, int index);
289 * of_property_read_string_index() - Find and read a string from a multiple
291 * @np: device node from which the property value is to be read.
292 * @propname: name of the property to be searched.
293 * @index: index of the string in the list of strings
294 * @out_string: pointer to null terminated return string, modified only if
297 * Search for a property in a device tree node and retrieve a null
298 * terminated string value (pointer to data, not a copy) in the list of strings
299 * contained in that property.
300 * Returns 0 on success, -EINVAL if the property does not exist, -ENODATA if
301 * property does not have a value, and -EILSEQ if the string is not
302 * null-terminated within the length of the property data.
304 * The out_string pointer is modified only if a valid string can be decoded.
306 static inline int of_property_read_string_index(const struct device_node *np,
307 const char *propname,
308 int index, const char **output)
310 int rc = of_property_read_string_helper(np, propname, output, 1, index);
311 return rc < 0 ? rc : 0;
315 * of_property_count_strings() - Find and return the number of strings from a
316 * multiple strings property.
317 * @np: device node from which the property value is to be read.
318 * @propname: name of the property to be searched.
320 * Search for a property in a device tree node and retrieve the number of null
321 * terminated string contain in it. Returns the number of strings on
322 * success, -EINVAL if the property does not exist, -ENODATA if property
323 * does not have a value, and -EILSEQ if the string is not null-terminated
324 * within the length of the property data.
326 static inline int of_property_count_strings(const struct device_node *np,
327 const char *propname)
329 return of_property_read_string_helper(np, propname, NULL, 0, 0);
333 * of_parse_phandle - Resolve a phandle property to a device_node pointer
334 * @np: Pointer to device node holding phandle property
335 * @phandle_name: Name of property holding a phandle value
336 * @index: For properties holding a table of phandles, this is the index into
339 * Returns the device_node pointer with refcount incremented. Use
340 * of_node_put() on it when done.
342 struct device_node *of_parse_phandle(const struct device_node *np,
343 const char *phandle_name, int index);
346 * of_parse_phandle_with_args() - Find a node pointed by phandle in a list
348 * @np: pointer to a device tree node containing a list
349 * @list_name: property name that contains a list
350 * @cells_name: property name that specifies phandles' arguments count
351 * @index: index of a phandle to parse out
352 * @out_args: optional pointer to output arguments structure (will be filled)
353 * @return 0 on success (with @out_args filled out if not NULL), -ENOENT if
354 * @list_name does not exist, -EINVAL if a phandle was not found,
355 * @cells_name could not be found, the arguments were truncated or there
356 * were too many arguments.
358 * This function is useful to parse lists of phandles and their arguments.
359 * Returns 0 on success and fills out_args, on error returns appropriate
362 * Caller is responsible to call of_node_put() on the returned out_args->np
376 * list = <&phandle1 1 2 &phandle2 3>;
379 * To get a device_node of the `node2' node you may call this:
380 * of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args);
382 int of_parse_phandle_with_args(const struct device_node *np,
383 const char *list_name, const char *cells_name,
384 int index, struct of_phandle_args *out_args);
387 * of_count_phandle_with_args() - Count the number of phandle in a list
389 * @np: pointer to a device tree node containing a list
390 * @list_name: property name that contains a list
391 * @cells_name: property name that specifies phandles' arguments count
392 * @return number of phandle found, -ENOENT if
393 * @list_name does not exist, -EINVAL if a phandle was not found,
394 * @cells_name could not be found, the arguments were truncated or there
395 * were too many arguments.
397 * Returns number of phandle found on success, on error returns appropriate
401 int of_count_phandle_with_args(const struct device_node *np,
402 const char *list_name, const char *cells_name);
405 * of_alias_scan() - Scan all properties of the 'aliases' node
407 * The function scans all the properties of the 'aliases' node and populates
408 * the lookup table with the properties. It returns the number of alias
409 * properties found, or an error code in case of failure.
411 * @return 9 if OK, -ENOMEM if not enough memory
413 int of_alias_scan(void);
416 * of_alias_get_id - Get alias id for the given device_node
418 * Travels the lookup table to get the alias id for the given device_node and
421 * @np: Pointer to the given device_node
422 * @stem: Alias stem of the given device_node
423 * @return alias ID, if found, else -ENODEV
425 int of_alias_get_id(const struct device_node *np, const char *stem);
428 * of_get_stdout() - Get node to use for stdout
430 * @return node referred to by stdout-path alias, or NULL if none
432 struct device_node *of_get_stdout(void);