1 /* SPDX-License-Identifier: GPL-2.0+ */ 2 /* 3 * Function to read values from the device tree node attached to a udevice. 4 * 5 * Copyright (c) 2017 Google, Inc 6 * Written by Simon Glass <sjg@chromium.org> 7 */ 8 9 #ifndef _DM_READ_H 10 #define _DM_READ_H 11 12 #include <dm/fdtaddr.h> 13 #include <dm/ofnode.h> 14 #include <dm/uclass.h> 15 16 struct resource; 17 18 #if CONFIG_IS_ENABLED(OF_LIVE) 19 static inline const struct device_node *dev_np(struct udevice *dev) 20 { 21 return ofnode_to_np(dev->node); 22 } 23 #else 24 static inline const struct device_node *dev_np(struct udevice *dev) 25 { 26 return NULL; 27 } 28 #endif 29 30 /** 31 * dev_ofnode() - get the DT node reference associated with a udevice 32 * 33 * @dev: device to check 34 * @return reference of the the device's DT node 35 */ 36 static inline ofnode dev_ofnode(struct udevice *dev) 37 { 38 return dev->node; 39 } 40 41 static inline bool dev_of_valid(struct udevice *dev) 42 { 43 return ofnode_valid(dev_ofnode(dev)); 44 } 45 46 #ifndef CONFIG_DM_DEV_READ_INLINE 47 /** 48 * dev_read_u32() - read a 32-bit integer from a device's DT property 49 * 50 * @dev: device to read DT property from 51 * @propname: name of the property to read from 52 * @outp: place to put value (if found) 53 * @return 0 if OK, -ve on error 54 */ 55 int dev_read_u32(struct udevice *dev, const char *propname, u32 *outp); 56 57 /** 58 * dev_read_u32_default() - read a 32-bit integer from a device's DT property 59 * 60 * @dev: device to read DT property from 61 * @propname: name of the property to read from 62 * @def: default value to return if the property has no value 63 * @return property value, or @def if not found 64 */ 65 int dev_read_u32_default(struct udevice *dev, const char *propname, int def); 66 67 /** 68 * dev_read_string() - Read a string from a device's DT property 69 * 70 * @dev: device to read DT property from 71 * @propname: name of the property to read 72 * @return string from property value, or NULL if there is no such property 73 */ 74 const char *dev_read_string(struct udevice *dev, const char *propname); 75 76 /** 77 * dev_read_bool() - read a boolean value from a device's DT property 78 * 79 * @dev: device to read DT property from 80 * @propname: name of property to read 81 * @return true if property is present (meaning true), false if not present 82 */ 83 bool dev_read_bool(struct udevice *dev, const char *propname); 84 85 /** 86 * dev_read_subnode() - find a named subnode of a device 87 * 88 * @dev: device whose DT node contains the subnode 89 * @subnode_name: name of subnode to find 90 * @return reference to subnode (which can be invalid if there is no such 91 * subnode) 92 */ 93 ofnode dev_read_subnode(struct udevice *dev, const char *subbnode_name); 94 95 /** 96 * dev_read_size() - read the size of a property 97 * 98 * @dev: device to check 99 * @propname: property to check 100 * @return size of property if present, or -EINVAL if not 101 */ 102 int dev_read_size(struct udevice *dev, const char *propname); 103 104 /** 105 * dev_read_addr_index() - Get the indexed reg property of a device 106 * 107 * @dev: Device to read from 108 * @index: the 'reg' property can hold a list of <addr, size> pairs 109 * and @index is used to select which one is required 110 * 111 * @return address or FDT_ADDR_T_NONE if not found 112 */ 113 fdt_addr_t dev_read_addr_index(struct udevice *dev, int index); 114 115 /** 116 * dev_read_addr() - Get the reg property of a device 117 * 118 * @dev: Device to read from 119 * 120 * @return address or FDT_ADDR_T_NONE if not found 121 */ 122 fdt_addr_t dev_read_addr(struct udevice *dev); 123 124 /** 125 * dev_read_addr_ptr() - Get the reg property of a device 126 * as a pointer 127 * 128 * @dev: Device to read from 129 * 130 * @return pointer or NULL if not found 131 */ 132 void *dev_read_addr_ptr(struct udevice *dev); 133 134 /** 135 * dev_read_addr_size() - get address and size from a device property 136 * 137 * This does no address translation. It simply reads an property that contains 138 * an address and a size value, one after the other. 139 * 140 * @dev: Device to read from 141 * @propname: property to read 142 * @sizep: place to put size value (on success) 143 * @return address value, or FDT_ADDR_T_NONE on error 144 */ 145 fdt_addr_t dev_read_addr_size(struct udevice *dev, const char *propname, 146 fdt_size_t *sizep); 147 148 /** 149 * dev_read_name() - get the name of a device's node 150 * 151 * @node: valid node to look up 152 * @return name of node 153 */ 154 const char *dev_read_name(struct udevice *dev); 155 156 /** 157 * dev_read_stringlist_search() - find string in a string list and return index 158 * 159 * Note that it is possible for this function to succeed on property values 160 * that are not NUL-terminated. That's because the function will stop after 161 * finding the first occurrence of @string. This can for example happen with 162 * small-valued cell properties, such as #address-cells, when searching for 163 * the empty string. 164 * 165 * @dev: device to check 166 * @propname: name of the property containing the string list 167 * @string: string to look up in the string list 168 * 169 * @return: 170 * the index of the string in the list of strings 171 * -ENODATA if the property is not found 172 * -EINVAL on some other error 173 */ 174 int dev_read_stringlist_search(struct udevice *dev, const char *property, 175 const char *string); 176 177 /** 178 * dev_read_string_index() - obtain an indexed string from a string list 179 * 180 * @dev: device to examine 181 * @propname: name of the property containing the string list 182 * @index: index of the string to return 183 * @out: return location for the string 184 * 185 * @return: 186 * length of string, if found or -ve error value if not found 187 */ 188 int dev_read_string_index(struct udevice *dev, const char *propname, int index, 189 const char **outp); 190 191 /** 192 * dev_read_string_count() - find the number of strings in a string list 193 * 194 * @dev: device to examine 195 * @propname: name of the property containing the string list 196 * @return: 197 * number of strings in the list, or -ve error value if not found 198 */ 199 int dev_read_string_count(struct udevice *dev, const char *propname); 200 /** 201 * dev_read_phandle_with_args() - Find a node pointed by phandle in a list 202 * 203 * This function is useful to parse lists of phandles and their arguments. 204 * Returns 0 on success and fills out_args, on error returns appropriate 205 * errno value. 206 * 207 * Caller is responsible to call of_node_put() on the returned out_args->np 208 * pointer. 209 * 210 * Example: 211 * 212 * phandle1: node1 { 213 * #list-cells = <2>; 214 * } 215 * 216 * phandle2: node2 { 217 * #list-cells = <1>; 218 * } 219 * 220 * node3 { 221 * list = <&phandle1 1 2 &phandle2 3>; 222 * } 223 * 224 * To get a device_node of the `node2' node you may call this: 225 * dev_read_phandle_with_args(dev, "list", "#list-cells", 0, 1, &args); 226 * 227 * @dev: device whose node containing a list 228 * @list_name: property name that contains a list 229 * @cells_name: property name that specifies phandles' arguments count 230 * @cells_count: Cell count to use if @cells_name is NULL 231 * @index: index of a phandle to parse out 232 * @out_args: optional pointer to output arguments structure (will be filled) 233 * @return 0 on success (with @out_args filled out if not NULL), -ENOENT if 234 * @list_name does not exist, -EINVAL if a phandle was not found, 235 * @cells_name could not be found, the arguments were truncated or there 236 * were too many arguments. 237 */ 238 int dev_read_phandle_with_args(struct udevice *dev, const char *list_name, 239 const char *cells_name, int cell_count, 240 int index, 241 struct ofnode_phandle_args *out_args); 242 243 /** 244 * dev_count_phandle_with_args() - Return phandle number in a list 245 * 246 * This function is usefull to get phandle number contained in a property list. 247 * For example, this allows to allocate the right amount of memory to keep 248 * clock's reference contained into the "clocks" property. 249 * 250 * 251 * @dev: device whose node containing a list 252 * @list_name: property name that contains a list 253 * @cells_name: property name that specifies phandles' arguments count 254 * @Returns number of phandle found on success, on error returns appropriate 255 * errno value. 256 */ 257 258 int dev_count_phandle_with_args(struct udevice *dev, const char *list_name, 259 const char *cells_name); 260 261 /** 262 * dev_read_addr_cells() - Get the number of address cells for a device's node 263 * 264 * This walks back up the tree to find the closest #address-cells property 265 * which controls the given node. 266 * 267 * @dev: device to check 268 * @return number of address cells this node uses 269 */ 270 int dev_read_addr_cells(struct udevice *dev); 271 272 /** 273 * dev_read_size_cells() - Get the number of size cells for a device's node 274 * 275 * This walks back up the tree to find the closest #size-cells property 276 * which controls the given node. 277 * 278 * @dev: device to check 279 * @return number of size cells this node uses 280 */ 281 int dev_read_size_cells(struct udevice *dev); 282 283 /** 284 * dev_read_addr_cells() - Get the address cells property in a node 285 * 286 * This function matches fdt_address_cells(). 287 * 288 * @dev: device to check 289 * @return number of address cells this node uses 290 */ 291 int dev_read_simple_addr_cells(struct udevice *dev); 292 293 /** 294 * dev_read_size_cells() - Get the size cells property in a node 295 * 296 * This function matches fdt_size_cells(). 297 * 298 * @dev: device to check 299 * @return number of size cells this node uses 300 */ 301 int dev_read_simple_size_cells(struct udevice *dev); 302 303 /** 304 * dev_read_phandle() - Get the phandle from a device 305 * 306 * @dev: device to check 307 * @return phandle (1 or greater), or 0 if no phandle or other error 308 */ 309 int dev_read_phandle(struct udevice *dev); 310 311 /** 312 * dev_read_prop()- - read a property from a device's node 313 * 314 * @dev: device to check 315 * @propname: property to read 316 * @lenp: place to put length on success 317 * @return pointer to property, or NULL if not found 318 */ 319 const void *dev_read_prop(struct udevice *dev, const char *propname, int *lenp); 320 321 /** 322 * dev_read_alias_seq() - Get the alias sequence number of a node 323 * 324 * This works out whether a node is pointed to by an alias, and if so, the 325 * sequence number of that alias. Aliases are of the form <base><num> where 326 * <num> is the sequence number. For example spi2 would be sequence number 2. 327 * 328 * @dev: device to look up 329 * @devnump: set to the sequence number if one is found 330 * @return 0 if a sequence was found, -ve if not 331 */ 332 int dev_read_alias_seq(struct udevice *dev, int *devnump); 333 334 /** 335 * dev_read_u32_array() - Find and read an array of 32 bit integers 336 * 337 * Search for a property in a device node and read 32-bit value(s) from 338 * it. 339 * 340 * The out_values is modified only if a valid u32 value can be decoded. 341 * 342 * @dev: device to look up 343 * @propname: name of the property to read 344 * @out_values: pointer to return value, modified only if return value is 0 345 * @sz: number of array elements to read 346 * @return 0 on success, -EINVAL if the property does not exist, -ENODATA if 347 * property does not have a value, and -EOVERFLOW if the property data isn't 348 * large enough. 349 */ 350 int dev_read_u32_array(struct udevice *dev, const char *propname, 351 u32 *out_values, size_t sz); 352 353 /** 354 * dev_read_first_subnode() - find the first subnode of a device's node 355 * 356 * @dev: device to look up 357 * @return reference to the first subnode (which can be invalid if the device's 358 * node has no subnodes) 359 */ 360 ofnode dev_read_first_subnode(struct udevice *dev); 361 362 /** 363 * ofnode_next_subnode() - find the next sibling of a subnode 364 * 365 * @node: valid reference to previous node (sibling) 366 * @return reference to the next subnode (which can be invalid if the node 367 * has no more siblings) 368 */ 369 ofnode dev_read_next_subnode(ofnode node); 370 371 /** 372 * dev_read_u8_array_ptr() - find an 8-bit array 373 * 374 * Look up a device's node property and return a pointer to its contents as a 375 * byte array of given length. The property must have at least enough data 376 * for the array (count bytes). It may have more, but this will be ignored. 377 * The data is not copied. 378 * 379 * @dev: device to look up 380 * @propname: name of property to find 381 * @sz: number of array elements 382 * @return pointer to byte array if found, or NULL if the property is not 383 * found or there is not enough data 384 */ 385 const uint8_t *dev_read_u8_array_ptr(struct udevice *dev, const char *propname, 386 size_t sz); 387 388 /** 389 * dev_read_enabled() - check whether a node is enabled 390 * 391 * This looks for a 'status' property. If this exists, then returns 1 if 392 * the status is 'ok' and 0 otherwise. If there is no status property, 393 * it returns 1 on the assumption that anything mentioned should be enabled 394 * by default. 395 * 396 * @dev: device to examine 397 * @return integer value 0 (not enabled) or 1 (enabled) 398 */ 399 int dev_read_enabled(struct udevice *dev); 400 401 /** 402 * dev_read_resource() - obtain an indexed resource from a device. 403 * 404 * @dev: device to examine 405 * @index index of the resource to retrieve (0 = first) 406 * @res returns the resource 407 * @return 0 if ok, negative on error 408 */ 409 int dev_read_resource(struct udevice *dev, uint index, struct resource *res); 410 411 /** 412 * dev_read_resource_byname() - obtain a named resource from a device. 413 * 414 * @dev: device to examine 415 * @name: name of the resource to retrieve 416 * @res: returns the resource 417 * @return 0 if ok, negative on error 418 */ 419 int dev_read_resource_byname(struct udevice *dev, const char *name, 420 struct resource *res); 421 422 /** 423 * dev_translate_address() - Tranlate a device-tree address 424 * 425 * Translate an address from the device-tree into a CPU physical address. This 426 * function walks up the tree and applies the various bus mappings along the 427 * way. 428 * 429 * @dev: device giving the context in which to translate the address 430 * @in_addr: pointer to the address to translate 431 * @return the translated address; OF_BAD_ADDR on error 432 */ 433 u64 dev_translate_address(struct udevice *dev, const fdt32_t *in_addr); 434 #else /* CONFIG_DM_DEV_READ_INLINE is enabled */ 435 436 static inline int dev_read_u32(struct udevice *dev, 437 const char *propname, u32 *outp) 438 { 439 return ofnode_read_u32(dev_ofnode(dev), propname, outp); 440 } 441 442 static inline int dev_read_u32_default(struct udevice *dev, 443 const char *propname, int def) 444 { 445 return ofnode_read_u32_default(dev_ofnode(dev), propname, def); 446 } 447 448 static inline const char *dev_read_string(struct udevice *dev, 449 const char *propname) 450 { 451 return ofnode_read_string(dev_ofnode(dev), propname); 452 } 453 454 static inline bool dev_read_bool(struct udevice *dev, const char *propname) 455 { 456 return ofnode_read_bool(dev_ofnode(dev), propname); 457 } 458 459 static inline ofnode dev_read_subnode(struct udevice *dev, 460 const char *subbnode_name) 461 { 462 return ofnode_find_subnode(dev_ofnode(dev), subbnode_name); 463 } 464 465 static inline int dev_read_size(struct udevice *dev, const char *propname) 466 { 467 return ofnode_read_size(dev_ofnode(dev), propname); 468 } 469 470 static inline fdt_addr_t dev_read_addr_index(struct udevice *dev, int index) 471 { 472 return devfdt_get_addr_index(dev, index); 473 } 474 475 static inline fdt_addr_t dev_read_addr(struct udevice *dev) 476 { 477 return devfdt_get_addr(dev); 478 } 479 480 static inline void *dev_read_addr_ptr(struct udevice *dev) 481 { 482 return devfdt_get_addr_ptr(dev); 483 } 484 485 static inline fdt_addr_t dev_read_addr_size(struct udevice *dev, 486 const char *propname, 487 fdt_size_t *sizep) 488 { 489 return ofnode_get_addr_size(dev_ofnode(dev), propname, sizep); 490 } 491 492 static inline const char *dev_read_name(struct udevice *dev) 493 { 494 return ofnode_get_name(dev_ofnode(dev)); 495 } 496 497 static inline int dev_read_stringlist_search(struct udevice *dev, 498 const char *propname, 499 const char *string) 500 { 501 return ofnode_stringlist_search(dev_ofnode(dev), propname, string); 502 } 503 504 static inline int dev_read_string_index(struct udevice *dev, 505 const char *propname, int index, 506 const char **outp) 507 { 508 return ofnode_read_string_index(dev_ofnode(dev), propname, index, outp); 509 } 510 511 static inline int dev_read_string_count(struct udevice *dev, 512 const char *propname) 513 { 514 return ofnode_read_string_count(dev_ofnode(dev), propname); 515 } 516 517 static inline int dev_read_phandle_with_args(struct udevice *dev, 518 const char *list_name, const char *cells_name, int cell_count, 519 int index, struct ofnode_phandle_args *out_args) 520 { 521 return ofnode_parse_phandle_with_args(dev_ofnode(dev), list_name, 522 cells_name, cell_count, index, 523 out_args); 524 } 525 526 static inline int dev_count_phandle_with_args(struct udevice *dev, 527 const char *list_name, const char *cells_name) 528 { 529 return ofnode_count_phandle_with_args(dev_ofnode(dev), list_name, 530 cells_name); 531 } 532 533 static inline int dev_read_addr_cells(struct udevice *dev) 534 { 535 /* NOTE: this call should walk up the parent stack */ 536 return fdt_address_cells(gd->fdt_blob, dev_of_offset(dev)); 537 } 538 539 static inline int dev_read_size_cells(struct udevice *dev) 540 { 541 /* NOTE: this call should walk up the parent stack */ 542 return fdt_size_cells(gd->fdt_blob, dev_of_offset(dev)); 543 } 544 545 static inline int dev_read_simple_addr_cells(struct udevice *dev) 546 { 547 return fdt_address_cells(gd->fdt_blob, dev_of_offset(dev)); 548 } 549 550 static inline int dev_read_simple_size_cells(struct udevice *dev) 551 { 552 return fdt_size_cells(gd->fdt_blob, dev_of_offset(dev)); 553 } 554 555 static inline int dev_read_phandle(struct udevice *dev) 556 { 557 return fdt_get_phandle(gd->fdt_blob, dev_of_offset(dev)); 558 } 559 560 static inline const void *dev_read_prop(struct udevice *dev, 561 const char *propname, int *lenp) 562 { 563 return ofnode_get_property(dev_ofnode(dev), propname, lenp); 564 } 565 566 static inline int dev_read_alias_seq(struct udevice *dev, int *devnump) 567 { 568 return fdtdec_get_alias_seq(gd->fdt_blob, dev->uclass->uc_drv->name, 569 dev_of_offset(dev), devnump); 570 } 571 572 static inline int dev_read_u32_array(struct udevice *dev, const char *propname, 573 u32 *out_values, size_t sz) 574 { 575 return ofnode_read_u32_array(dev_ofnode(dev), propname, out_values, sz); 576 } 577 578 static inline ofnode dev_read_first_subnode(struct udevice *dev) 579 { 580 return ofnode_first_subnode(dev_ofnode(dev)); 581 } 582 583 static inline ofnode dev_read_next_subnode(ofnode node) 584 { 585 return ofnode_next_subnode(node); 586 } 587 588 static inline const uint8_t *dev_read_u8_array_ptr(struct udevice *dev, 589 const char *propname, size_t sz) 590 { 591 return ofnode_read_u8_array_ptr(dev_ofnode(dev), propname, sz); 592 } 593 594 static inline int dev_read_enabled(struct udevice *dev) 595 { 596 return fdtdec_get_is_enabled(gd->fdt_blob, dev_of_offset(dev)); 597 } 598 599 static inline int dev_read_resource(struct udevice *dev, uint index, 600 struct resource *res) 601 { 602 return ofnode_read_resource(dev_ofnode(dev), index, res); 603 } 604 605 static inline int dev_read_resource_byname(struct udevice *dev, 606 const char *name, 607 struct resource *res) 608 { 609 return ofnode_read_resource_byname(dev_ofnode(dev), name, res); 610 } 611 612 static inline u64 dev_translate_address(struct udevice *dev, const fdt32_t *in_addr) 613 { 614 return ofnode_translate_address(dev_ofnode(dev), in_addr); 615 } 616 617 #endif /* CONFIG_DM_DEV_READ_INLINE */ 618 619 /** 620 * dev_for_each_subnode() - Helper function to iterate through subnodes 621 * 622 * This creates a for() loop which works through the subnodes in a device's 623 * device-tree node. 624 * 625 * @subnode: ofnode holding the current subnode 626 * @dev: device to use for interation (struct udevice *) 627 */ 628 #define dev_for_each_subnode(subnode, dev) \ 629 for (subnode = dev_read_first_subnode(dev); \ 630 ofnode_valid(subnode); \ 631 subnode = ofnode_next_subnode(subnode)) 632 633 #endif 634