1 /* 2 * Function to read values from the device tree node attached to a udevice. 3 * 4 * Copyright (c) 2017 Google, Inc 5 * Written by Simon Glass <sjg@chromium.org> 6 * 7 * SPDX-License-Identifier: GPL-2.0+ 8 */ 9 10 #ifndef _DM_READ_H 11 #define _DM_READ_H 12 13 #include <dm/fdtaddr.h> 14 #include <dm/ofnode.h> 15 #include <dm/uclass.h> 16 17 struct resource; 18 19 #if CONFIG_IS_ENABLED(OF_LIVE) 20 static inline const struct device_node *dev_np(struct udevice *dev) 21 { 22 return ofnode_to_np(dev->node); 23 } 24 #else 25 static inline const struct device_node *dev_np(struct udevice *dev) 26 { 27 return NULL; 28 } 29 #endif 30 31 /** 32 * dev_ofnode() - get the DT node reference associated with a udevice 33 * 34 * @dev: device to check 35 * @return reference of the the device's DT node 36 */ 37 static inline ofnode dev_ofnode(struct udevice *dev) 38 { 39 return dev->node; 40 } 41 42 static inline bool dev_of_valid(struct udevice *dev) 43 { 44 return ofnode_valid(dev_ofnode(dev)); 45 } 46 47 #ifndef CONFIG_DM_DEV_READ_INLINE 48 /** 49 * dev_read_u32_default() - read a 32-bit integer from a device's DT property 50 * 51 * @dev: device to read DT property from 52 * @propname: name of the property to read from 53 * @def: default value to return if the property has no value 54 * @return property value, or @def if not found 55 */ 56 int dev_read_u32_default(struct udevice *dev, const char *propname, int def); 57 58 /** 59 * dev_read_s32_default() - read a signed 32-bit integer from a device's DT property 60 * 61 * @dev: device to read DT property from 62 * @propname: name of the property to read from 63 * @def: default value to return if the property has no value 64 * @return property value, or @def if not found 65 */ 66 int dev_read_s32_default(struct udevice *dev, const char *propname, int def); 67 68 /** 69 * dev_read_string() - Read a string from a device's DT property 70 * 71 * @dev: device to read DT property from 72 * @propname: name of the property to read 73 * @return string from property value, or NULL if there is no such property 74 */ 75 const char *dev_read_string(struct udevice *dev, const char *propname); 76 77 /** 78 * dev_read_bool() - read a boolean value from a device's DT property 79 * 80 * @dev: device to read DT property from 81 * @propname: name of property to read 82 * @return true if property is present (meaning true), false if not present 83 */ 84 bool dev_read_bool(struct udevice *dev, const char *propname); 85 86 /** 87 * dev_read_subnode() - find a named subnode of a device 88 * 89 * @dev: device whose DT node contains the subnode 90 * @subnode_name: name of subnode to find 91 * @return reference to subnode (which can be invalid if there is no such 92 * subnode) 93 */ 94 ofnode dev_read_subnode(struct udevice *dev, const char *subbnode_name); 95 96 /** 97 * dev_read_size() - read the size of a property 98 * 99 * @dev: device to check 100 * @propname: property to check 101 * @return size of property if present, or -EINVAL if not 102 */ 103 int dev_read_size(struct udevice *dev, const char *propname); 104 105 /** 106 * dev_read_addr_index() - Get the indexed reg property of a device 107 * 108 * @dev: Device to read from 109 * @index: the 'reg' property can hold a list of <addr, size> pairs 110 * and @index is used to select which one is required 111 * 112 * @return address or FDT_ADDR_T_NONE if not found 113 */ 114 fdt_addr_t dev_read_addr_index(struct udevice *dev, int index); 115 116 /** 117 * dev_read_addr() - Get the reg property of a device 118 * 119 * @dev: Device to read from 120 * 121 * @return address or FDT_ADDR_T_NONE if not found 122 */ 123 fdt_addr_t dev_read_addr(struct udevice *dev); 124 125 /** 126 * dev_read_addr_ptr() - Get the reg property of a device 127 * as a pointer 128 * 129 * @dev: Device to read from 130 * 131 * @return pointer or NULL if not found 132 */ 133 void *dev_read_addr_ptr(struct udevice *dev); 134 135 /** 136 * dev_read_addr_size() - get address and size from a device property 137 * 138 * This does no address translation. It simply reads an property that contains 139 * an address and a size value, one after the other. 140 * 141 * @dev: Device to read from 142 * @propname: property to read 143 * @sizep: place to put size value (on success) 144 * @return address value, or FDT_ADDR_T_NONE on error 145 */ 146 fdt_addr_t dev_read_addr_size(struct udevice *dev, const char *propname, 147 fdt_size_t *sizep); 148 149 /** 150 * dev_read_name() - get the name of a device's node 151 * 152 * @node: valid node to look up 153 * @return name of node 154 */ 155 const char *dev_read_name(struct udevice *dev); 156 157 /** 158 * dev_read_stringlist_search() - find string in a string list and return index 159 * 160 * Note that it is possible for this function to succeed on property values 161 * that are not NUL-terminated. That's because the function will stop after 162 * finding the first occurrence of @string. This can for example happen with 163 * small-valued cell properties, such as #address-cells, when searching for 164 * the empty string. 165 * 166 * @dev: device to check 167 * @propname: name of the property containing the string list 168 * @string: string to look up in the string list 169 * 170 * @return: 171 * the index of the string in the list of strings 172 * -ENODATA if the property is not found 173 * -EINVAL on some other error 174 */ 175 int dev_read_stringlist_search(struct udevice *dev, const char *property, 176 const char *string); 177 178 /** 179 * dev_read_string_index() - obtain an indexed string from a string list 180 * 181 * @dev: device to examine 182 * @propname: name of the property containing the string list 183 * @index: index of the string to return 184 * @out: return location for the string 185 * 186 * @return: 187 * length of string, if found or -ve error value if not found 188 */ 189 int dev_read_string_index(struct udevice *dev, const char *propname, int index, 190 const char **outp); 191 192 /** 193 * dev_read_string_count() - find the number of strings in a string list 194 * 195 * @dev: device to examine 196 * @propname: name of the property containing the string list 197 * @return: 198 * number of strings in the list, or -ve error value if not found 199 */ 200 int dev_read_string_count(struct udevice *dev, const char *propname); 201 /** 202 * dev_read_phandle_with_args() - Find a node pointed by phandle in a list 203 * 204 * This function is useful to parse lists of phandles and their arguments. 205 * Returns 0 on success and fills out_args, on error returns appropriate 206 * errno value. 207 * 208 * Caller is responsible to call of_node_put() on the returned out_args->np 209 * pointer. 210 * 211 * Example: 212 * 213 * phandle1: node1 { 214 * #list-cells = <2>; 215 * } 216 * 217 * phandle2: node2 { 218 * #list-cells = <1>; 219 * } 220 * 221 * node3 { 222 * list = <&phandle1 1 2 &phandle2 3>; 223 * } 224 * 225 * To get a device_node of the `node2' node you may call this: 226 * dev_read_phandle_with_args(dev, "list", "#list-cells", 0, 1, &args); 227 * 228 * @dev: device whose node containing a list 229 * @list_name: property name that contains a list 230 * @cells_name: property name that specifies phandles' arguments count 231 * @cells_count: Cell count to use if @cells_name is NULL 232 * @index: index of a phandle to parse out 233 * @out_args: optional pointer to output arguments structure (will be filled) 234 * @return 0 on success (with @out_args filled out if not NULL), -ENOENT if 235 * @list_name does not exist, -EINVAL if a phandle was not found, 236 * @cells_name could not be found, the arguments were truncated or there 237 * were too many arguments. 238 */ 239 int dev_read_phandle_with_args(struct udevice *dev, const char *list_name, 240 const char *cells_name, int cell_count, 241 int index, 242 struct ofnode_phandle_args *out_args); 243 244 /** 245 * dev_count_phandle_with_args() - Return phandle number in a list 246 * 247 * This function is usefull to get phandle number contained in a property list. 248 * For example, this allows to allocate the right amount of memory to keep 249 * clock's reference contained into the "clocks" property. 250 * 251 * 252 * @dev: device whose node containing a list 253 * @list_name: property name that contains a list 254 * @cells_name: property name that specifies phandles' arguments count 255 * @Returns number of phandle found on success, on error returns appropriate 256 * errno value. 257 */ 258 259 int dev_count_phandle_with_args(struct udevice *dev, const char *list_name, 260 const char *cells_name); 261 262 /** 263 * dev_read_addr_cells() - Get the number of address cells for a device's node 264 * 265 * This walks back up the tree to find the closest #address-cells property 266 * which controls the given node. 267 * 268 * @dev: devioe to check 269 * @return number of address cells this node uses 270 */ 271 int dev_read_addr_cells(struct udevice *dev); 272 273 /** 274 * dev_read_size_cells() - Get the number of size cells for a device's node 275 * 276 * This walks back up the tree to find the closest #size-cells property 277 * which controls the given node. 278 * 279 * @dev: devioe to check 280 * @return number of size cells this node uses 281 */ 282 int dev_read_size_cells(struct udevice *dev); 283 284 /** 285 * dev_read_addr_cells() - Get the address cells property in a node 286 * 287 * This function matches fdt_address_cells(). 288 * 289 * @dev: devioe to check 290 * @return number of address cells this node uses 291 */ 292 int dev_read_simple_addr_cells(struct udevice *dev); 293 294 /** 295 * dev_read_size_cells() - Get the size cells property in a node 296 * 297 * This function matches fdt_size_cells(). 298 * 299 * @dev: devioe to check 300 * @return number of size cells this node uses 301 */ 302 int dev_read_simple_size_cells(struct udevice *dev); 303 304 /** 305 * dev_read_phandle() - Get the phandle from a device 306 * 307 * @dev: device to check 308 * @return phandle (1 or greater), or 0 if no phandle or other error 309 */ 310 int dev_read_phandle(struct udevice *dev); 311 312 /** 313 * dev_read_prop()- - read a property from a device's node 314 * 315 * @dev: device to check 316 * @propname: property to read 317 * @lenp: place to put length on success 318 * @return pointer to property, or NULL if not found 319 */ 320 const void *dev_read_prop(struct udevice *dev, const char *propname, int *lenp); 321 322 /** 323 * dev_read_first_prop()- get the reference of the first property 324 * 325 * Get reference to the first property of the node, it is used to iterate 326 * and read all the property with dev_read_prop_by_prop(). 327 * 328 * @dev: device to check 329 * @prop: place to put argument reference 330 * @return 0 if OK, -ve on error. -FDT_ERR_NOTFOUND if not found 331 */ 332 int dev_read_first_prop(struct udevice *dev, struct ofprop *prop); 333 334 /** 335 * ofnode_get_next_property() - get the reference of the next property 336 * 337 * Get reference to the next property of the node, it is used to iterate 338 * and read all the property with dev_read_prop_by_prop(). 339 * 340 * @prop: reference of current argument and place to put reference of next one 341 * @return 0 if OK, -ve on error. -FDT_ERR_NOTFOUND if not found 342 */ 343 int dev_read_next_prop(struct ofprop *prop); 344 345 /** 346 * dev_read_prop_by_prop() - get a pointer to the value of a property 347 * 348 * Get value for the property identified by the provided reference. 349 * 350 * @prop: reference on property 351 * @propname: If non-NULL, place to property name on success, 352 * @lenp: If non-NULL, place to put length on success 353 * @return 0 if OK, -ve on error. -FDT_ERR_NOTFOUND if not found 354 */ 355 const void *dev_read_prop_by_prop(struct ofprop *prop, 356 const char **propname, int *lenp); 357 358 /** 359 * dev_read_alias_seq() - Get the alias sequence number of a node 360 * 361 * This works out whether a node is pointed to by an alias, and if so, the 362 * sequence number of that alias. Aliases are of the form <base><num> where 363 * <num> is the sequence number. For example spi2 would be sequence number 2. 364 * 365 * @dev: device to look up 366 * @devnump: set to the sequence number if one is found 367 * @return 0 if a sequence was found, -ve if not 368 */ 369 int dev_read_alias_seq(struct udevice *dev, int *devnump); 370 371 /** 372 * dev_read_u32_array() - Find and read an array of 32 bit integers 373 * 374 * Search for a property in a device node and read 32-bit value(s) from 375 * it. 376 * 377 * The out_values is modified only if a valid u32 value can be decoded. 378 * 379 * @dev: device to look up 380 * @propname: name of the property to read 381 * @out_values: pointer to return value, modified only if return value is 0 382 * @sz: number of array elements to read 383 * @return 0 on success, -EINVAL if the property does not exist, -ENODATA if 384 * property does not have a value, and -EOVERFLOW if the property data isn't 385 * large enough. 386 */ 387 int dev_read_u32_array(struct udevice *dev, const char *propname, 388 u32 *out_values, size_t sz); 389 390 /** 391 * dev_write_u32_array() - Find and write an array of 32 bit integers 392 * 393 * Search for a property in a device node and write 32-bit value(s) to 394 * it. 395 * 396 * The out_values is modified only if a valid u32 value can be decoded. 397 * 398 * @dev: device to look up 399 * @propname: name of the property to read 400 * @values: pointer to update value, modified only if return value is 0 401 * @sz: number of array elements to read 402 * @return 0 on success, -EINVAL if the property does not exist, -ENODATA if 403 * property does not have a value, and -EOVERFLOW if the property data isn't 404 * large enough. 405 */ 406 int dev_write_u32_array(struct udevice *dev, const char *propname, 407 u32 *values, size_t sz); 408 409 /** 410 * dev_read_first_subnode() - find the first subnode of a device's node 411 * 412 * @dev: device to look up 413 * @return reference to the first subnode (which can be invalid if the device's 414 * node has no subnodes) 415 */ 416 ofnode dev_read_first_subnode(struct udevice *dev); 417 418 /** 419 * ofnode_next_subnode() - find the next sibling of a subnode 420 * 421 * @node: valid reference to previous node (sibling) 422 * @return reference to the next subnode (which can be invalid if the node 423 * has no more siblings) 424 */ 425 ofnode dev_read_next_subnode(ofnode node); 426 427 /** 428 * dev_read_u8_array_ptr() - find an 8-bit array 429 * 430 * Look up a device's node property and return a pointer to its contents as a 431 * byte array of given length. The property must have at least enough data 432 * for the array (count bytes). It may have more, but this will be ignored. 433 * The data is not copied. 434 * 435 * @dev: device to look up 436 * @propname: name of property to find 437 * @sz: number of array elements 438 * @return pointer to byte array if found, or NULL if the property is not 439 * found or there is not enough data 440 */ 441 const uint8_t *dev_read_u8_array_ptr(struct udevice *dev, const char *propname, 442 size_t sz); 443 444 /** 445 * dev_read_enabled() - check whether a node is enabled 446 * 447 * This looks for a 'status' property. If this exists, then returns 1 if 448 * the status is 'ok' and 0 otherwise. If there is no status property, 449 * it returns 1 on the assumption that anything mentioned should be enabled 450 * by default. 451 * 452 * @dev: device to examine 453 * @return integer value 0 (not enabled) or 1 (enabled) 454 */ 455 int dev_read_enabled(struct udevice *dev); 456 457 /** 458 * dev_read_resource() - obtain an indexed resource from a device. 459 * 460 * @dev: device to examine 461 * @index index of the resource to retrieve (0 = first) 462 * @res returns the resource 463 * @return 0 if ok, negative on error 464 */ 465 int dev_read_resource(struct udevice *dev, uint index, struct resource *res); 466 467 /** 468 * dev_read_resource_byname() - obtain a named resource from a device. 469 * 470 * @dev: device to examine 471 * @name: name of the resource to retrieve 472 * @res: returns the resource 473 * @return 0 if ok, negative on error 474 */ 475 int dev_read_resource_byname(struct udevice *dev, const char *name, 476 struct resource *res); 477 478 /** 479 * dev_translate_address() - Tranlate a device-tree address 480 * 481 * Translate an address from the device-tree into a CPU physical address. This 482 * function walks up the tree and applies the various bus mappings along the 483 * way. 484 * 485 * @dev: device giving the context in which to translate the address 486 * @in_addr: pointer to the address to translate 487 * @return the translated address; OF_BAD_ADDR on error 488 */ 489 u64 dev_translate_address(struct udevice *dev, const fdt32_t *in_addr); 490 #else /* CONFIG_DM_DEV_READ_INLINE is enabled */ 491 492 static inline int dev_read_u32_default(struct udevice *dev, 493 const char *propname, int def) 494 { 495 return ofnode_read_u32_default(dev_ofnode(dev), propname, def); 496 } 497 498 static inline const char *dev_read_string(struct udevice *dev, 499 const char *propname) 500 { 501 return ofnode_read_string(dev_ofnode(dev), propname); 502 } 503 504 static inline bool dev_read_bool(struct udevice *dev, const char *propname) 505 { 506 return ofnode_read_bool(dev_ofnode(dev), propname); 507 } 508 509 static inline ofnode dev_read_subnode(struct udevice *dev, 510 const char *subbnode_name) 511 { 512 return ofnode_find_subnode(dev_ofnode(dev), subbnode_name); 513 } 514 515 static inline int dev_read_size(struct udevice *dev, const char *propname) 516 { 517 return ofnode_read_size(dev_ofnode(dev), propname); 518 } 519 520 static inline fdt_addr_t dev_read_addr_index(struct udevice *dev, int index) 521 { 522 return devfdt_get_addr_index(dev, index); 523 } 524 525 static inline fdt_addr_t dev_read_addr(struct udevice *dev) 526 { 527 return devfdt_get_addr(dev); 528 } 529 530 static inline void *dev_read_addr_ptr(struct udevice *dev) 531 { 532 return devfdt_get_addr_ptr(dev); 533 } 534 535 static inline fdt_addr_t dev_read_addr_size(struct udevice *dev, 536 const char *propname, 537 fdt_size_t *sizep) 538 { 539 return ofnode_get_addr_size(dev_ofnode(dev), propname, sizep); 540 } 541 542 static inline const char *dev_read_name(struct udevice *dev) 543 { 544 if (!dev_of_valid(dev)) 545 return NULL; 546 return ofnode_get_name(dev_ofnode(dev)); 547 } 548 549 static inline int dev_read_stringlist_search(struct udevice *dev, 550 const char *propname, 551 const char *string) 552 { 553 return ofnode_stringlist_search(dev_ofnode(dev), propname, string); 554 } 555 556 static inline int dev_read_string_index(struct udevice *dev, 557 const char *propname, int index, 558 const char **outp) 559 { 560 return ofnode_read_string_index(dev_ofnode(dev), propname, index, outp); 561 } 562 563 static inline int dev_read_string_count(struct udevice *dev, 564 const char *propname) 565 { 566 return ofnode_read_string_count(dev_ofnode(dev), propname); 567 } 568 569 static inline int dev_read_phandle_with_args(struct udevice *dev, 570 const char *list_name, const char *cells_name, int cell_count, 571 int index, struct ofnode_phandle_args *out_args) 572 { 573 return ofnode_parse_phandle_with_args(dev_ofnode(dev), list_name, 574 cells_name, cell_count, index, 575 out_args); 576 } 577 578 static inline int dev_count_phandle_with_args(struct udevice *dev, 579 const char *list_name, const char *cells_name) 580 { 581 return ofnode_count_phandle_with_args(dev_ofnode(dev), list_name, 582 cells_name); 583 } 584 585 static inline int dev_read_addr_cells(struct udevice *dev) 586 { 587 /* NOTE: this call should walk up the parent stack */ 588 return fdt_address_cells(gd->fdt_blob, dev_of_offset(dev)); 589 } 590 591 static inline int dev_read_size_cells(struct udevice *dev) 592 { 593 /* NOTE: this call should walk up the parent stack */ 594 return fdt_size_cells(gd->fdt_blob, dev_of_offset(dev)); 595 } 596 597 static inline int dev_read_simple_addr_cells(struct udevice *dev) 598 { 599 return fdt_address_cells(gd->fdt_blob, dev_of_offset(dev)); 600 } 601 602 static inline int dev_read_simple_size_cells(struct udevice *dev) 603 { 604 return fdt_size_cells(gd->fdt_blob, dev_of_offset(dev)); 605 } 606 607 static inline int dev_read_phandle(struct udevice *dev) 608 { 609 return fdt_get_phandle(gd->fdt_blob, dev_of_offset(dev)); 610 } 611 612 static inline const void *dev_read_prop(struct udevice *dev, 613 const char *propname, int *lenp) 614 { 615 return ofnode_get_property(dev_ofnode(dev), propname, lenp); 616 } 617 618 static inline int dev_read_first_prop(struct udevice *dev, struct ofprop *prop) 619 { 620 return ofnode_get_first_property(dev_ofnode(dev), prop); 621 } 622 623 static inline int dev_read_next_prop(struct ofprop *prop) 624 { 625 return ofnode_get_next_property(prop); 626 } 627 628 static inline const void *dev_read_prop_by_prop(struct ofprop *prop, 629 const char **propname, 630 int *lenp) 631 { 632 return ofnode_get_property_by_prop(prop, propname, lenp); 633 } 634 635 static inline int dev_read_alias_seq(struct udevice *dev, int *devnump) 636 { 637 return fdtdec_get_alias_seq(gd->fdt_blob, dev->uclass->uc_drv->name, 638 dev_of_offset(dev), devnump); 639 } 640 641 static inline int dev_read_u32_array(struct udevice *dev, const char *propname, 642 u32 *out_values, size_t sz) 643 { 644 if (!dev_of_valid(dev)) 645 return -EINVAL; 646 return ofnode_read_u32_array(dev_ofnode(dev), propname, out_values, sz); 647 } 648 649 static inline ofnode dev_read_first_subnode(struct udevice *dev) 650 { 651 return ofnode_first_subnode(dev_ofnode(dev)); 652 } 653 654 static inline ofnode dev_read_next_subnode(ofnode node) 655 { 656 return ofnode_next_subnode(node); 657 } 658 659 static inline const uint8_t *dev_read_u8_array_ptr(struct udevice *dev, 660 const char *propname, size_t sz) 661 { 662 return ofnode_read_u8_array_ptr(dev_ofnode(dev), propname, sz); 663 } 664 665 static inline int dev_read_enabled(struct udevice *dev) 666 { 667 return fdtdec_get_is_enabled(gd->fdt_blob, dev_of_offset(dev)); 668 } 669 670 static inline int dev_read_resource(struct udevice *dev, uint index, 671 struct resource *res) 672 { 673 return ofnode_read_resource(dev_ofnode(dev), index, res); 674 } 675 676 static inline int dev_read_resource_byname(struct udevice *dev, 677 const char *name, 678 struct resource *res) 679 { 680 return ofnode_read_resource_byname(dev_ofnode(dev), name, res); 681 } 682 683 static inline u64 dev_translate_address(struct udevice *dev, const fdt32_t *in_addr) 684 { 685 return ofnode_translate_address(dev_ofnode(dev), in_addr); 686 } 687 688 #endif /* CONFIG_DM_DEV_READ_INLINE */ 689 690 /** 691 * dev_for_each_subnode() - Helper function to iterate through subnodes 692 * 693 * This creates a for() loop which works through the subnodes in a device's 694 * device-tree node. 695 * 696 * @subnode: ofnode holding the current subnode 697 * @dev: device to use for interation (struct udevice *) 698 */ 699 #define dev_for_each_subnode(subnode, dev) \ 700 for (subnode = dev_read_first_subnode(dev); \ 701 ofnode_valid(subnode); \ 702 subnode = ofnode_next_subnode(subnode)) 703 704 /** 705 * dev_for_each_property() - Helper function to iterate through property 706 * 707 * This creates a for() loop which works through the property in a device's 708 * device-tree node. 709 * 710 * @prop: struct ofprop holding the current property 711 * @dev: device to use for interation (struct udevice *) 712 */ 713 #define dev_for_each_property(prop, dev) \ 714 for (int ret_prop = dev_read_first_prop(dev, &prop); \ 715 !ret_prop; \ 716 ret_prop = dev_read_next_prop(&prop)) 717 718 #endif 719