1/* SPDX-License-Identifier: GPL-2.0+ */ 2/* 3 * Originally from Linux v4.9 4 * Copyright (C) 1996-2005 Paul Mackerras. 5 * 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. 9 * 10 * Copyright (c) 2017 Google, Inc 11 * Written by Simon Glass <sjg@chromium.org> 12 * 13 * Modified for U-Boot 14 * Copyright (c) 2017 Google, Inc 15 */ 16 17#ifndef _DM_OF_ACCESS_H 18#define _DM_OF_ACCESS_H 19 20#include <dm/of.h> 21 22/** 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 26 * 27 * Returns a node pointer with refcount incremented, use 28 * of_node_put() on it when done. 29 */ 30struct device_node *of_find_all_nodes(struct device_node *prev); 31 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) 35 36/* Dummy functions to mirror Linux. These are not used in U-Boot */ 37#define of_node_get(x) (x) 38static inline void of_node_put(const struct device_node *np) { } 39 40/** 41 * of_n_addr_cells() - Get the number of address cells for a node 42 * 43 * This walks back up the tree to find the closest #address-cells property 44 * which controls the given node. 45 * 46 * @np: Node pointer to check 47 * @return number of address cells this node uses 48 */ 49int of_n_addr_cells(const struct device_node *np); 50 51/** 52 * of_n_size_cells() - Get the number of size cells for a node 53 * 54 * This walks back up the tree to find the closest #size-cells property 55 * which controls the given node. 56 * 57 * @np: Node pointer to check 58 * @return number of size cells this node uses 59 */ 60int of_n_size_cells(const struct device_node *np); 61 62/** 63 * of_simple_addr_cells() - Get the address cells property in a node 64 * 65 * This function matches fdt_address_cells(). 66 * 67 * @np: Node pointer to check 68 * @return value of #address-cells property in this node, or 2 if none 69 */ 70int of_simple_addr_cells(const struct device_node *np); 71 72/** 73 * of_simple_size_cells() - Get the size cells property in a node 74 * 75 * This function matches fdt_size_cells(). 76 * 77 * @np: Node pointer to check 78 * @return value of #size-cells property in this node, or 2 if none 79 */ 80int of_simple_size_cells(const struct device_node *np); 81 82/** 83 * of_find_property() - find a property in a node 84 * 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 89 */ 90struct property *of_find_property(const struct device_node *np, 91 const char *name, int *lenp); 92 93/** 94 * of_get_property() - get a property value 95 * 96 * Find a property with a given name for a given node and return the value. 97 * 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 102 */ 103const void *of_get_property(const struct device_node *np, const char *name, 104 int *lenp); 105 106/** 107 * of_get_first_property()- get to the pointer of the first property 108 * 109 * Get pointer to the first property of the node, it is used to iterate 110 * and read all the property with of_get_next_property_by_prop(). 111 * 112 * @np: Pointer to device node 113 * @return pointer to property or NULL if not found 114 */ 115const struct property *of_get_first_property(const struct device_node *np); 116 117/** 118 * of_get_next_property() - get to the pointer of the next property 119 * 120 * Get pointer to the next property of the node, it is used to iterate 121 * and read all the property with of_get_property_by_prop(). 122 * 123 * @np: Pointer to device node 124 * @property: pointer of the current property 125 * @return pointer to next property or NULL if not found 126 */ 127const struct property *of_get_next_property(const struct device_node *np, 128 const struct property *property); 129 130/** 131 * of_get_property_by_prop() - get a property value of a node property 132 * 133 * Get value for the property identified by node and property pointer. 134 * 135 * @node: node to read 136 * @property: pointer of the property to read 137 * @propname: place to property name on success 138 * @lenp: place to put length on success 139 * @return pointer to property value or NULL if error 140 */ 141const void *of_get_property_by_prop(const struct device_node *np, 142 const struct property *property, 143 const char **name, 144 int *lenp); 145 146/** 147 * of_device_is_compatible() - Check if the node matches given constraints 148 * @device: pointer to node 149 * @compat: required compatible string, NULL or "" for any match 150 * @type: required device_type value, NULL or "" for any match 151 * @name: required node name, NULL or "" for any match 152 * 153 * Checks if the given @compat, @type and @name strings match the 154 * properties of the given @device. A constraints can be skipped by 155 * passing NULL or an empty string as the constraint. 156 * 157 * @return 0 for no match, and a positive integer on match. The return 158 * value is a relative score with larger values indicating better 159 * matches. The score is weighted for the most specific compatible value 160 * to get the highest score. Matching type is next, followed by matching 161 * name. Practically speaking, this results in the following priority 162 * order for matches: 163 * 164 * 1. specific compatible && type && name 165 * 2. specific compatible && type 166 * 3. specific compatible && name 167 * 4. specific compatible 168 * 5. general compatible && type && name 169 * 6. general compatible && type 170 * 7. general compatible && name 171 * 8. general compatible 172 * 9. type && name 173 * 10. type 174 * 11. name 175 */ 176int of_device_is_compatible(const struct device_node *np, const char *compat, 177 const char *type, const char *name); 178 179/** 180 * of_device_is_available() - check if a device is available for use 181 * 182 * @device: Node to check for availability 183 * 184 * @return true if the status property is absent or set to "okay", false 185 * otherwise 186 */ 187bool of_device_is_available(const struct device_node *np); 188 189/** 190 * of_get_parent() - Get a node's parent, if any 191 * 192 * @node: Node to check 193 * @eturns a node pointer, or NULL if none 194 */ 195struct device_node *of_get_parent(const struct device_node *np); 196 197/** 198 * of_find_node_opts_by_path() - Find a node matching a full OF path 199 * 200 * @path: Either the full path to match, or if the path does not start with 201 * '/', the name of a property of the /aliases node (an alias). In the 202 * case of an alias, the node matching the alias' value will be returned. 203 * @opts: Address of a pointer into which to store the start of an options 204 * string appended to the end of the path with a ':' separator. Can be NULL 205 * 206 * Valid paths: 207 * /foo/bar Full path 208 * foo Valid alias 209 * foo/bar Valid alias + relative path 210 * 211 * @return a node pointer or NULL if not found 212 */ 213struct device_node *of_find_node_opts_by_path(const char *path, 214 const char **opts); 215 216static inline struct device_node *of_find_node_by_path(const char *path) 217{ 218 return of_find_node_opts_by_path(path, NULL); 219} 220 221/** 222 * of_find_compatible_node() - find a node based on its compatible string 223 * 224 * Find a node based on type and one of the tokens in its "compatible" property 225 * @from: Node to start searching from or NULL. the node you pass will not be 226 * searched, only the next one will; typically, you pass what the previous 227 * call returned. 228 * @type: The type string to match "device_type" or NULL to ignore 229 * @compatible: The string to match to one of the tokens in the device 230 * "compatible" list. 231 * @return node pointer or NULL if not found 232 */ 233struct device_node *of_find_compatible_node(struct device_node *from, 234 const char *type, const char *compatible); 235 236/** 237 * of_find_node_by_prop_value() - find a node with a given property value 238 * 239 * Find a node based on a property value. 240 * @from: Node to start searching from or NULL. the node you pass will not be 241 * searched, only the next one will; typically, you pass what the previous 242 * call returned. 243 * @propname: property name to check 244 * @propval: property value to search for 245 * @proplen: length of the value in propval 246 * @return node pointer or NULL if not found 247 */ 248struct device_node *of_find_node_by_prop_value(struct device_node *from, 249 const char *propname, 250 const void *propval, 251 int proplen); 252/** 253 * of_find_node_by_phandle() - Find a node given a phandle 254 * 255 * @handle: phandle of the node to find 256 * 257 * @return node pointer, or NULL if not found 258 */ 259struct device_node *of_find_node_by_phandle(phandle handle); 260 261/** 262 * of_read_u32() - Find and read a 32-bit integer from a property 263 * 264 * Search for a property in a device node and read a 32-bit value from 265 * it. 266 * 267 * @np: device node from which the property value is to be read. 268 * @propname: name of the property to be searched. 269 * @outp: pointer to return value, modified only if return value is 0. 270 * 271 * @return 0 on success, -EINVAL if the property does not exist, 272 * -ENODATA if property does not have a value, and -EOVERFLOW if the 273 * property data isn't large enough. 274 */ 275int of_read_u32(const struct device_node *np, const char *propname, u32 *outp); 276 277/** 278 * of_read_u32_index() - Find and read a 32-bit value from a multi-value 279 * property 280 * 281 * Search for a property in a device node and read a 32-bit value from 282 * it. 283 * 284 * @np: device node from which the property value is to be read. 285 * @propname: name of the property to be searched. 286 * @index: index of the u32 in the list of values 287 * @outp: pointer to return value, modified only if return value is 0. 288 * 289 * @return 0 on success, -EINVAL if the property does not exist, 290 * -ENODATA if property does not have a value, and -EOVERFLOW if the 291 * property data isn't large enough. 292 */ 293int of_read_u32_index(const struct device_node *np, const char *propname, 294 int index, u32 *outp); 295 296/** 297 * of_read_u64() - Find and read a 64-bit integer from a property 298 * 299 * Search for a property in a device node and read a 64-bit value from 300 * it. 301 * 302 * @np: device node from which the property value is to be read. 303 * @propname: name of the property to be searched. 304 * @outp: pointer to return value, modified only if return value is 0. 305 * 306 * @return 0 on success, -EINVAL if the property does not exist, 307 * -ENODATA if property does not have a value, and -EOVERFLOW if the 308 * property data isn't large enough. 309 */ 310int of_read_u64(const struct device_node *np, const char *propname, u64 *outp); 311 312/** 313 * of_read_u32_array() - Find and read an array of 32 bit integers 314 * 315 * Search for a property in a device node and read 32-bit value(s) from 316 * it. 317 * 318 * @np: device node from which the property value is to be read. 319 * @propname: name of the property to be searched. 320 * @out_values: pointer to return value, modified only if return value is 0. 321 * @sz: number of array elements to read 322 * @return 0 on success, -EINVAL if the property does not exist, -ENODATA 323 * if property does not have a value, and -EOVERFLOW is longer than sz. 324 */ 325int of_read_u32_array(const struct device_node *np, const char *propname, 326 u32 *out_values, size_t sz); 327 328/** 329 * of_property_match_string() - Find string in a list and return index 330 * 331 * This function searches a string list property and returns the index 332 * of a specific string value. 333 * 334 * @np: pointer to node containing string list property 335 * @propname: string list property name 336 * @string: pointer to string to search for in string list 337 * @return 0 on success, -EINVAL if the property does not exist, -ENODATA 338 * if property does not have a value, and -EOVERFLOW is longer than sz. 339 */ 340int of_property_match_string(const struct device_node *np, const char *propname, 341 const char *string); 342 343int of_property_read_string_helper(const struct device_node *np, 344 const char *propname, const char **out_strs, 345 size_t sz, int index); 346 347/** 348 * of_property_read_string_index() - Find and read a string from a multiple 349 * strings property. 350 * @np: device node from which the property value is to be read. 351 * @propname: name of the property to be searched. 352 * @index: index of the string in the list of strings 353 * @out_string: pointer to null terminated return string, modified only if 354 * return value is 0. 355 * 356 * Search for a property in a device tree node and retrieve a null 357 * terminated string value (pointer to data, not a copy) in the list of strings 358 * contained in that property. 359 * Returns 0 on success, -EINVAL if the property does not exist, -ENODATA if 360 * property does not have a value, and -EILSEQ if the string is not 361 * null-terminated within the length of the property data. 362 * 363 * The out_string pointer is modified only if a valid string can be decoded. 364 */ 365static inline int of_property_read_string_index(const struct device_node *np, 366 const char *propname, 367 int index, const char **output) 368{ 369 int rc = of_property_read_string_helper(np, propname, output, 1, index); 370 return rc < 0 ? rc : 0; 371} 372 373/** 374 * of_property_count_strings() - Find and return the number of strings from a 375 * multiple strings property. 376 * @np: device node from which the property value is to be read. 377 * @propname: name of the property to be searched. 378 * 379 * Search for a property in a device tree node and retrieve the number of null 380 * terminated string contain in it. Returns the number of strings on 381 * success, -EINVAL if the property does not exist, -ENODATA if property 382 * does not have a value, and -EILSEQ if the string is not null-terminated 383 * within the length of the property data. 384 */ 385static inline int of_property_count_strings(const struct device_node *np, 386 const char *propname) 387{ 388 return of_property_read_string_helper(np, propname, NULL, 0, 0); 389} 390 391/** 392 * of_parse_phandle - Resolve a phandle property to a device_node pointer 393 * @np: Pointer to device node holding phandle property 394 * @phandle_name: Name of property holding a phandle value 395 * @index: For properties holding a table of phandles, this is the index into 396 * the table 397 * 398 * Returns the device_node pointer with refcount incremented. Use 399 * of_node_put() on it when done. 400 */ 401struct device_node *of_parse_phandle(const struct device_node *np, 402 const char *phandle_name, int index); 403 404/** 405 * of_parse_phandle_with_args() - Find a node pointed by phandle in a list 406 * 407 * @np: pointer to a device tree node containing a list 408 * @list_name: property name that contains a list 409 * @cells_name: property name that specifies phandles' arguments count 410 * @cells_count: Cell count to use if @cells_name is NULL 411 * @index: index of a phandle to parse out 412 * @out_args: optional pointer to output arguments structure (will be filled) 413 * @return 0 on success (with @out_args filled out if not NULL), -ENOENT if 414 * @list_name does not exist, -EINVAL if a phandle was not found, 415 * @cells_name could not be found, the arguments were truncated or there 416 * were too many arguments. 417 * 418 * This function is useful to parse lists of phandles and their arguments. 419 * Returns 0 on success and fills out_args, on error returns appropriate 420 * errno value. 421 * 422 * Caller is responsible to call of_node_put() on the returned out_args->np 423 * pointer. 424 * 425 * Example: 426 * 427 * phandle1: node1 { 428 * #list-cells = <2>; 429 * } 430 * 431 * phandle2: node2 { 432 * #list-cells = <1>; 433 * } 434 * 435 * node3 { 436 * list = <&phandle1 1 2 &phandle2 3>; 437 * } 438 * 439 * To get a device_node of the `node2' node you may call this: 440 * of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args); 441 */ 442int of_parse_phandle_with_args(const struct device_node *np, 443 const char *list_name, const char *cells_name, 444 int cells_count, int index, 445 struct of_phandle_args *out_args); 446 447/** 448 * of_count_phandle_with_args() - Count the number of phandle in a list 449 * 450 * @np: pointer to a device tree node containing a list 451 * @list_name: property name that contains a list 452 * @cells_name: property name that specifies phandles' arguments count 453 * @cells_count: Cell count to use if @cells_name is NULL 454 * @return number of phandle found, -ENOENT if 455 * @list_name does not exist, -EINVAL if a phandle was not found, 456 * @cells_name could not be found, the arguments were truncated or there 457 * were too many arguments. 458 * 459 * Returns number of phandle found on success, on error returns appropriate 460 * errno value. 461 * 462 */ 463int of_count_phandle_with_args(const struct device_node *np, 464 const char *list_name, const char *cells_name, 465 int cells_count); 466 467/** 468 * of_alias_scan() - Scan all properties of the 'aliases' node 469 * 470 * The function scans all the properties of the 'aliases' node and populates 471 * the lookup table with the properties. It returns the number of alias 472 * properties found, or an error code in case of failure. 473 * 474 * @return 9 if OK, -ENOMEM if not enough memory 475 */ 476int of_alias_scan(void); 477 478/** 479 * of_alias_get_id - Get alias id for the given device_node 480 * 481 * Travels the lookup table to get the alias id for the given device_node and 482 * alias stem. 483 * 484 * @np: Pointer to the given device_node 485 * @stem: Alias stem of the given device_node 486 * @return alias ID, if found, else -ENODEV 487 */ 488int of_alias_get_id(const struct device_node *np, const char *stem); 489 490/** 491 * of_alias_get_highest_id - Get highest alias id for the given stem 492 * @stem: Alias stem to be examined 493 * 494 * The function travels the lookup table to get the highest alias id for the 495 * given alias stem. 496 * @return alias ID, if found, else -1 497 */ 498int of_alias_get_highest_id(const char *stem); 499 500/** 501 * of_get_stdout() - Get node to use for stdout 502 * 503 * @return node referred to by stdout-path alias, or NULL if none 504 */ 505struct device_node *of_get_stdout(void); 506 507#endif 508