1 /* 2 * Copyright (c) 2011 The Chromium OS Authors. 3 * SPDX-License-Identifier: GPL-2.0+ 4 */ 5 6 #ifndef __fdtdec_h 7 #define __fdtdec_h 8 9 /* 10 * This file contains convenience functions for decoding useful and 11 * enlightening information from FDTs. It is intended to be used by device 12 * drivers and board-specific code within U-Boot. It aims to reduce the 13 * amount of FDT munging required within U-Boot itself, so that driver code 14 * changes to support FDT are minimized. 15 */ 16 17 #include <libfdt.h> 18 19 /* 20 * A typedef for a physical address. Note that fdt data is always big 21 * endian even on a litle endian machine. 22 */ 23 #ifdef CONFIG_PHYS_64BIT 24 typedef u64 fdt_addr_t; 25 typedef u64 fdt_size_t; 26 #define FDT_ADDR_T_NONE (-1ULL) 27 #define fdt_addr_to_cpu(reg) be64_to_cpu(reg) 28 #define fdt_size_to_cpu(reg) be64_to_cpu(reg) 29 #else 30 typedef u32 fdt_addr_t; 31 typedef u32 fdt_size_t; 32 #define FDT_ADDR_T_NONE (-1U) 33 #define fdt_addr_to_cpu(reg) be32_to_cpu(reg) 34 #define fdt_size_to_cpu(reg) be32_to_cpu(reg) 35 #endif 36 37 /* Information obtained about memory from the FDT */ 38 struct fdt_memory { 39 fdt_addr_t start; 40 fdt_addr_t end; 41 }; 42 43 /* 44 * Information about a resource. start is the first address of the resource 45 * and end is the last address (inclusive). The length of the resource will 46 * be equal to: end - start + 1. 47 */ 48 struct fdt_resource { 49 fdt_addr_t start; 50 fdt_addr_t end; 51 }; 52 53 /** 54 * Compute the size of a resource. 55 * 56 * @param res the resource to operate on 57 * @return the size of the resource 58 */ 59 static inline fdt_size_t fdt_resource_size(const struct fdt_resource *res) 60 { 61 return res->end - res->start + 1; 62 } 63 64 /** 65 * Compat types that we know about and for which we might have drivers. 66 * Each is named COMPAT_<dir>_<filename> where <dir> is the directory 67 * within drivers. 68 */ 69 enum fdt_compat_id { 70 COMPAT_UNKNOWN, 71 COMPAT_NVIDIA_TEGRA20_USB, /* Tegra20 USB port */ 72 COMPAT_NVIDIA_TEGRA30_USB, /* Tegra30 USB port */ 73 COMPAT_NVIDIA_TEGRA114_USB, /* Tegra114 USB port */ 74 COMPAT_NVIDIA_TEGRA114_I2C, /* Tegra114 I2C w/single clock source */ 75 COMPAT_NVIDIA_TEGRA20_I2C, /* Tegra20 i2c */ 76 COMPAT_NVIDIA_TEGRA20_DVC, /* Tegra20 dvc (really just i2c) */ 77 COMPAT_NVIDIA_TEGRA20_EMC, /* Tegra20 memory controller */ 78 COMPAT_NVIDIA_TEGRA20_EMC_TABLE, /* Tegra20 memory timing table */ 79 COMPAT_NVIDIA_TEGRA20_KBC, /* Tegra20 Keyboard */ 80 COMPAT_NVIDIA_TEGRA20_NAND, /* Tegra2 NAND controller */ 81 COMPAT_NVIDIA_TEGRA20_PWM, /* Tegra 2 PWM controller */ 82 COMPAT_NVIDIA_TEGRA20_DC, /* Tegra 2 Display controller */ 83 COMPAT_NVIDIA_TEGRA124_SDMMC, /* Tegra124 SDMMC controller */ 84 COMPAT_NVIDIA_TEGRA30_SDMMC, /* Tegra30 SDMMC controller */ 85 COMPAT_NVIDIA_TEGRA20_SDMMC, /* Tegra20 SDMMC controller */ 86 COMPAT_NVIDIA_TEGRA20_SFLASH, /* Tegra 2 SPI flash controller */ 87 COMPAT_NVIDIA_TEGRA20_SLINK, /* Tegra 2 SPI SLINK controller */ 88 COMPAT_NVIDIA_TEGRA114_SPI, /* Tegra 114 SPI controller */ 89 COMPAT_SMSC_LAN9215, /* SMSC 10/100 Ethernet LAN9215 */ 90 COMPAT_SAMSUNG_EXYNOS5_SROMC, /* Exynos5 SROMC */ 91 COMPAT_SAMSUNG_S3C2440_I2C, /* Exynos I2C Controller */ 92 COMPAT_SAMSUNG_EXYNOS5_SOUND, /* Exynos Sound */ 93 COMPAT_WOLFSON_WM8994_CODEC, /* Wolfson WM8994 Sound Codec */ 94 COMPAT_SAMSUNG_EXYNOS_SPI, /* Exynos SPI */ 95 COMPAT_GOOGLE_CROS_EC, /* Google CROS_EC Protocol */ 96 COMPAT_GOOGLE_CROS_EC_KEYB, /* Google CROS_EC Keyboard */ 97 COMPAT_SAMSUNG_EXYNOS_EHCI, /* Exynos EHCI controller */ 98 COMPAT_SAMSUNG_EXYNOS5_XHCI, /* Exynos5 XHCI controller */ 99 COMPAT_SAMSUNG_EXYNOS_USB_PHY, /* Exynos phy controller for usb2.0 */ 100 COMPAT_SAMSUNG_EXYNOS5_USB3_PHY,/* Exynos phy controller for usb3.0 */ 101 COMPAT_SAMSUNG_EXYNOS_TMU, /* Exynos TMU */ 102 COMPAT_SAMSUNG_EXYNOS_FIMD, /* Exynos Display controller */ 103 COMPAT_SAMSUNG_EXYNOS_MIPI_DSI, /* Exynos mipi dsi */ 104 COMPAT_SAMSUNG_EXYNOS5_DP, /* Exynos Display port controller */ 105 COMPAT_SAMSUNG_EXYNOS_DWMMC, /* Exynos DWMMC controller */ 106 COMPAT_SAMSUNG_EXYNOS_MMC, /* Exynos MMC controller */ 107 COMPAT_SAMSUNG_EXYNOS_SERIAL, /* Exynos UART */ 108 COMPAT_MAXIM_MAX77686_PMIC, /* MAX77686 PMIC */ 109 COMPAT_GENERIC_SPI_FLASH, /* Generic SPI Flash chip */ 110 COMPAT_MAXIM_98095_CODEC, /* MAX98095 Codec */ 111 COMPAT_INFINEON_SLB9635_TPM, /* Infineon SLB9635 TPM */ 112 COMPAT_INFINEON_SLB9645_TPM, /* Infineon SLB9645 TPM */ 113 COMPAT_SAMSUNG_EXYNOS5_I2C, /* Exynos5 High Speed I2C Controller */ 114 COMPAT_SANDBOX_HOST_EMULATION, /* Sandbox emulation of a function */ 115 COMPAT_SANDBOX_LCD_SDL, /* Sandbox LCD emulation with SDL */ 116 COMPAT_TI_TPS65090, /* Texas Instrument TPS65090 */ 117 COMPAT_NXP_PTN3460, /* NXP PTN3460 DP/LVDS bridge */ 118 COMPAT_SAMSUNG_EXYNOS_SYSMMU, /* Exynos sysmmu */ 119 COMPAT_PARADE_PS8625, /* Parade PS8622 EDP->LVDS bridge */ 120 121 COMPAT_COUNT, 122 }; 123 124 /* GPIOs are numbered from 0 */ 125 enum { 126 FDT_GPIO_NONE = -1U, /* an invalid GPIO used to end our list */ 127 128 FDT_GPIO_ACTIVE_LOW = 1 << 0, /* input is active low (else high) */ 129 }; 130 131 /* This is the state of a GPIO pin as defined by the fdt */ 132 struct fdt_gpio_state { 133 const char *name; /* name of the fdt property defining this */ 134 uint gpio; /* GPIO number, or FDT_GPIO_NONE if none */ 135 u8 flags; /* FDT_GPIO_... flags */ 136 }; 137 138 /* This tells us whether a fdt_gpio_state record is valid or not */ 139 #define fdt_gpio_isvalid(x) ((x)->gpio != FDT_GPIO_NONE) 140 141 /** 142 * Read the GPIO taking into account the polarity of the pin. 143 * 144 * @param gpio pointer to the decoded gpio 145 * @return value of the gpio if successful, < 0 if unsuccessful 146 */ 147 int fdtdec_get_gpio(struct fdt_gpio_state *gpio); 148 149 /** 150 * Write the GPIO taking into account the polarity of the pin. 151 * 152 * @param gpio pointer to the decoded gpio 153 * @return 0 if successful 154 */ 155 int fdtdec_set_gpio(struct fdt_gpio_state *gpio, int val); 156 157 /** 158 * Find the next numbered alias for a peripheral. This is used to enumerate 159 * all the peripherals of a certain type. 160 * 161 * Do the first call with *upto = 0. Assuming /aliases/<name>0 exists then 162 * this function will return a pointer to the node the alias points to, and 163 * then update *upto to 1. Next time you call this function, the next node 164 * will be returned. 165 * 166 * All nodes returned will match the compatible ID, as it is assumed that 167 * all peripherals use the same driver. 168 * 169 * @param blob FDT blob to use 170 * @param name Root name of alias to search for 171 * @param id Compatible ID to look for 172 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more 173 */ 174 int fdtdec_next_alias(const void *blob, const char *name, 175 enum fdt_compat_id id, int *upto); 176 177 /** 178 * Find the compatible ID for a given node. 179 * 180 * Generally each node has at least one compatible string attached to it. 181 * This function looks through our list of known compatible strings and 182 * returns the corresponding ID which matches the compatible string. 183 * 184 * @param blob FDT blob to use 185 * @param node Node containing compatible string to find 186 * @return compatible ID, or COMPAT_UNKNOWN if we cannot find a match 187 */ 188 enum fdt_compat_id fdtdec_lookup(const void *blob, int node); 189 190 /** 191 * Find the next compatible node for a peripheral. 192 * 193 * Do the first call with node = 0. This function will return a pointer to 194 * the next compatible node. Next time you call this function, pass the 195 * value returned, and the next node will be provided. 196 * 197 * @param blob FDT blob to use 198 * @param node Start node for search 199 * @param id Compatible ID to look for (enum fdt_compat_id) 200 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more 201 */ 202 int fdtdec_next_compatible(const void *blob, int node, 203 enum fdt_compat_id id); 204 205 /** 206 * Find the next compatible subnode for a peripheral. 207 * 208 * Do the first call with node set to the parent and depth = 0. This 209 * function will return the offset of the next compatible node. Next time 210 * you call this function, pass the node value returned last time, with 211 * depth unchanged, and the next node will be provided. 212 * 213 * @param blob FDT blob to use 214 * @param node Start node for search 215 * @param id Compatible ID to look for (enum fdt_compat_id) 216 * @param depthp Current depth (set to 0 before first call) 217 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more 218 */ 219 int fdtdec_next_compatible_subnode(const void *blob, int node, 220 enum fdt_compat_id id, int *depthp); 221 222 /** 223 * Look up an address property in a node and return it as an address. 224 * The property must hold either one address with no trailing data or 225 * one address with a length. This is only tested on 32-bit machines. 226 * 227 * @param blob FDT blob 228 * @param node node to examine 229 * @param prop_name name of property to find 230 * @return address, if found, or FDT_ADDR_T_NONE if not 231 */ 232 fdt_addr_t fdtdec_get_addr(const void *blob, int node, 233 const char *prop_name); 234 235 /** 236 * Look up an address property in a node and return it as an address. 237 * The property must hold one address with a length. This is only tested 238 * on 32-bit machines. 239 * 240 * @param blob FDT blob 241 * @param node node to examine 242 * @param prop_name name of property to find 243 * @return address, if found, or FDT_ADDR_T_NONE if not 244 */ 245 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node, 246 const char *prop_name, fdt_size_t *sizep); 247 248 /** 249 * Look up a 32-bit integer property in a node and return it. The property 250 * must have at least 4 bytes of data. The value of the first cell is 251 * returned. 252 * 253 * @param blob FDT blob 254 * @param node node to examine 255 * @param prop_name name of property to find 256 * @param default_val default value to return if the property is not found 257 * @return integer value, if found, or default_val if not 258 */ 259 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name, 260 s32 default_val); 261 262 /** 263 * Look up a 64-bit integer property in a node and return it. The property 264 * must have at least 8 bytes of data (2 cells). The first two cells are 265 * concatenated to form a 8 bytes value, where the first cell is top half and 266 * the second cell is bottom half. 267 * 268 * @param blob FDT blob 269 * @param node node to examine 270 * @param prop_name name of property to find 271 * @param default_val default value to return if the property is not found 272 * @return integer value, if found, or default_val if not 273 */ 274 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name, 275 uint64_t default_val); 276 277 /** 278 * Checks whether a node is enabled. 279 * This looks for a 'status' property. If this exists, then returns 1 if 280 * the status is 'ok' and 0 otherwise. If there is no status property, 281 * it returns 1 on the assumption that anything mentioned should be enabled 282 * by default. 283 * 284 * @param blob FDT blob 285 * @param node node to examine 286 * @return integer value 0 (not enabled) or 1 (enabled) 287 */ 288 int fdtdec_get_is_enabled(const void *blob, int node); 289 290 /** 291 * Make sure we have a valid fdt available to control U-Boot. 292 * 293 * If not, a message is printed to the console if the console is ready. 294 * 295 * @return 0 if all ok, -1 if not 296 */ 297 int fdtdec_prepare_fdt(void); 298 299 /** 300 * Checks that we have a valid fdt available to control U-Boot. 301 302 * However, if not then for the moment nothing is done, since this function 303 * is called too early to panic(). 304 * 305 * @returns 0 306 */ 307 int fdtdec_check_fdt(void); 308 309 /** 310 * Find the nodes for a peripheral and return a list of them in the correct 311 * order. This is used to enumerate all the peripherals of a certain type. 312 * 313 * To use this, optionally set up a /aliases node with alias properties for 314 * a peripheral. For example, for usb you could have: 315 * 316 * aliases { 317 * usb0 = "/ehci@c5008000"; 318 * usb1 = "/ehci@c5000000"; 319 * }; 320 * 321 * Pass "usb" as the name to this function and will return a list of two 322 * nodes offsets: /ehci@c5008000 and ehci@c5000000. 323 * 324 * All nodes returned will match the compatible ID, as it is assumed that 325 * all peripherals use the same driver. 326 * 327 * If no alias node is found, then the node list will be returned in the 328 * order found in the fdt. If the aliases mention a node which doesn't 329 * exist, then this will be ignored. If nodes are found with no aliases, 330 * they will be added in any order. 331 * 332 * If there is a gap in the aliases, then this function return a 0 node at 333 * that position. The return value will also count these gaps. 334 * 335 * This function checks node properties and will not return nodes which are 336 * marked disabled (status = "disabled"). 337 * 338 * @param blob FDT blob to use 339 * @param name Root name of alias to search for 340 * @param id Compatible ID to look for 341 * @param node_list Place to put list of found nodes 342 * @param maxcount Maximum number of nodes to find 343 * @return number of nodes found on success, FTD_ERR_... on error 344 */ 345 int fdtdec_find_aliases_for_id(const void *blob, const char *name, 346 enum fdt_compat_id id, int *node_list, int maxcount); 347 348 /* 349 * This function is similar to fdtdec_find_aliases_for_id() except that it 350 * adds to the node_list that is passed in. Any 0 elements are considered 351 * available for allocation - others are considered already used and are 352 * skipped. 353 * 354 * You can use this by calling fdtdec_find_aliases_for_id() with an 355 * uninitialised array, then setting the elements that are returned to -1, 356 * say, then calling this function, perhaps with a different compat id. 357 * Any elements you get back that are >0 are new nodes added by the call 358 * to this function. 359 * 360 * Note that if you have some nodes with aliases and some without, you are 361 * sailing close to the wind. The call to fdtdec_find_aliases_for_id() with 362 * one compat_id may fill in positions for which you have aliases defined 363 * for another compat_id. When you later call *this* function with the second 364 * compat_id, the alias positions may already be used. A debug warning may 365 * be generated in this case, but it is safest to define aliases for all 366 * nodes when you care about the ordering. 367 */ 368 int fdtdec_add_aliases_for_id(const void *blob, const char *name, 369 enum fdt_compat_id id, int *node_list, int maxcount); 370 371 /** 372 * Get the alias sequence number of a node 373 * 374 * This works out whether a node is pointed to by an alias, and if so, the 375 * sequence number of that alias. Aliases are of the form <base><num> where 376 * <num> is the sequence number. For example spi2 would be sequence number 377 * 2. 378 * 379 * @param blob Device tree blob (if NULL, then error is returned) 380 * @param base Base name for alias (before the underscore) 381 * @param node Node to look up 382 * @param seqp This is set to the sequence number if one is found, 383 * but otherwise the value is left alone 384 * @return 0 if a sequence was found, -ve if not 385 */ 386 int fdtdec_get_alias_seq(const void *blob, const char *base, int node, 387 int *seqp); 388 389 /** 390 * Get the offset of the given alias node 391 * 392 * This looks up an alias in /aliases then finds the offset of that node. 393 * 394 * @param blob Device tree blob (if NULL, then error is returned) 395 * @param name Alias name, e.g. "console" 396 * @return Node offset referred to by that alias, or -ve FDT_ERR_... 397 */ 398 int fdtdec_get_alias_node(const void *blob, const char *name); 399 400 /** 401 * Get the offset of the given chosen node 402 * 403 * This looks up a property in /chosen containing the path to another node, 404 * then finds the offset of that node. 405 * 406 * @param blob Device tree blob (if NULL, then error is returned) 407 * @param name Property name, e.g. "stdout-path" 408 * @return Node offset referred to by that chosen node, or -ve FDT_ERR_... 409 */ 410 int fdtdec_get_chosen_node(const void *blob, const char *name); 411 412 /* 413 * Get the name for a compatible ID 414 * 415 * @param id Compatible ID to look for 416 * @return compatible string for that id 417 */ 418 const char *fdtdec_get_compatible(enum fdt_compat_id id); 419 420 /* Look up a phandle and follow it to its node. Then return the offset 421 * of that node. 422 * 423 * @param blob FDT blob 424 * @param node node to examine 425 * @param prop_name name of property to find 426 * @return node offset if found, -ve error code on error 427 */ 428 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name); 429 430 /** 431 * Look up a property in a node and return its contents in an integer 432 * array of given length. The property must have at least enough data for 433 * the array (4*count bytes). It may have more, but this will be ignored. 434 * 435 * @param blob FDT blob 436 * @param node node to examine 437 * @param prop_name name of property to find 438 * @param array array to fill with data 439 * @param count number of array elements 440 * @return 0 if ok, or -FDT_ERR_NOTFOUND if the property is not found, 441 * or -FDT_ERR_BADLAYOUT if not enough data 442 */ 443 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name, 444 u32 *array, int count); 445 446 /** 447 * Look up a property in a node and return a pointer to its contents as a 448 * unsigned int array of given length. The property must have at least enough 449 * data for the array ('count' cells). It may have more, but this will be 450 * ignored. The data is not copied. 451 * 452 * Note that you must access elements of the array with fdt32_to_cpu(), 453 * since the elements will be big endian even on a little endian machine. 454 * 455 * @param blob FDT blob 456 * @param node node to examine 457 * @param prop_name name of property to find 458 * @param count number of array elements 459 * @return pointer to array if found, or NULL if the property is not 460 * found or there is not enough data 461 */ 462 const u32 *fdtdec_locate_array(const void *blob, int node, 463 const char *prop_name, int count); 464 465 /** 466 * Look up a boolean property in a node and return it. 467 * 468 * A boolean properly is true if present in the device tree and false if not 469 * present, regardless of its value. 470 * 471 * @param blob FDT blob 472 * @param node node to examine 473 * @param prop_name name of property to find 474 * @return 1 if the properly is present; 0 if it isn't present 475 */ 476 int fdtdec_get_bool(const void *blob, int node, const char *prop_name); 477 478 /** 479 * Decode a single GPIOs from an FDT. 480 * 481 * If the property is not found, then the GPIO structure will still be 482 * initialised, with gpio set to FDT_GPIO_NONE. This makes it easy to 483 * provide optional GPIOs. 484 * 485 * @param blob FDT blob to use 486 * @param node Node to look at 487 * @param prop_name Node property name 488 * @param gpio gpio elements to fill from FDT 489 * @return 0 if ok, -FDT_ERR_NOTFOUND if the property is missing. 490 */ 491 int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name, 492 struct fdt_gpio_state *gpio); 493 494 /** 495 * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no 496 * terminating item. 497 * 498 * @param blob FDT blob to use 499 * @param node Node to look at 500 * @param prop_name Node property name 501 * @param gpio Array of gpio elements to fill from FDT. This will be 502 * untouched if either 0 or an error is returned 503 * @param max_count Maximum number of elements allowed 504 * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would 505 * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing. 506 */ 507 int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name, 508 struct fdt_gpio_state *gpio, int max_count); 509 510 /** 511 * Set up a GPIO pin according to the provided gpio information. At present this 512 * just requests the GPIO. 513 * 514 * If the gpio is FDT_GPIO_NONE, no action is taken. This makes it easy to 515 * deal with optional GPIOs. 516 * 517 * @param gpio GPIO info to use for set up 518 * @return 0 if all ok or gpio was FDT_GPIO_NONE; -1 on error 519 */ 520 int fdtdec_setup_gpio(struct fdt_gpio_state *gpio); 521 522 /** 523 * Look in the FDT for a config item with the given name and return its value 524 * as a 32-bit integer. The property must have at least 4 bytes of data. The 525 * value of the first cell is returned. 526 * 527 * @param blob FDT blob to use 528 * @param prop_name Node property name 529 * @param default_val default value to return if the property is not found 530 * @return integer value, if found, or default_val if not 531 */ 532 int fdtdec_get_config_int(const void *blob, const char *prop_name, 533 int default_val); 534 535 /** 536 * Look in the FDT for a config item with the given name 537 * and return whether it exists. 538 * 539 * @param blob FDT blob 540 * @param prop_name property name to look up 541 * @return 1, if it exists, or 0 if not 542 */ 543 int fdtdec_get_config_bool(const void *blob, const char *prop_name); 544 545 /** 546 * Look in the FDT for a config item with the given name and return its value 547 * as a string. 548 * 549 * @param blob FDT blob 550 * @param prop_name property name to look up 551 * @returns property string, NULL on error. 552 */ 553 char *fdtdec_get_config_string(const void *blob, const char *prop_name); 554 555 /* 556 * Look up a property in a node and return its contents in a byte 557 * array of given length. The property must have at least enough data for 558 * the array (count bytes). It may have more, but this will be ignored. 559 * 560 * @param blob FDT blob 561 * @param node node to examine 562 * @param prop_name name of property to find 563 * @param array array to fill with data 564 * @param count number of array elements 565 * @return 0 if ok, or -FDT_ERR_MISSING if the property is not found, 566 * or -FDT_ERR_BADLAYOUT if not enough data 567 */ 568 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name, 569 u8 *array, int count); 570 571 /** 572 * Look up a property in a node and return a pointer to its contents as a 573 * byte array of given length. The property must have at least enough data 574 * for the array (count bytes). It may have more, but this will be ignored. 575 * The data is not copied. 576 * 577 * @param blob FDT blob 578 * @param node node to examine 579 * @param prop_name name of property to find 580 * @param count number of array elements 581 * @return pointer to byte array if found, or NULL if the property is not 582 * found or there is not enough data 583 */ 584 const u8 *fdtdec_locate_byte_array(const void *blob, int node, 585 const char *prop_name, int count); 586 587 /** 588 * Look up a property in a node which contains a memory region address and 589 * size. Then return a pointer to this address. 590 * 591 * The property must hold one address with a length. This is only tested on 592 * 32-bit machines. 593 * 594 * @param blob FDT blob 595 * @param node node to examine 596 * @param prop_name name of property to find 597 * @param ptrp returns pointer to region, or NULL if no address 598 * @param size returns size of region 599 * @return 0 if ok, -1 on error (propery not found) 600 */ 601 int fdtdec_decode_region(const void *blob, int node, 602 const char *prop_name, void **ptrp, size_t *size); 603 604 /* A flash map entry, containing an offset and length */ 605 struct fmap_entry { 606 uint32_t offset; 607 uint32_t length; 608 }; 609 610 /** 611 * Read a flash entry from the fdt 612 * 613 * @param blob FDT blob 614 * @param node Offset of node to read 615 * @param name Name of node being read 616 * @param entry Place to put offset and size of this node 617 * @return 0 if ok, -ve on error 618 */ 619 int fdtdec_read_fmap_entry(const void *blob, int node, const char *name, 620 struct fmap_entry *entry); 621 622 /** 623 * Obtain an indexed resource from a device property. 624 * 625 * @param fdt FDT blob 626 * @param node node to examine 627 * @param property name of the property to parse 628 * @param index index of the resource to retrieve 629 * @param res returns the resource 630 * @return 0 if ok, negative on error 631 */ 632 int fdt_get_resource(const void *fdt, int node, const char *property, 633 unsigned int index, struct fdt_resource *res); 634 635 /** 636 * Obtain a named resource from a device property. 637 * 638 * Look up the index of the name in a list of strings and return the resource 639 * at that index. 640 * 641 * @param fdt FDT blob 642 * @param node node to examine 643 * @param property name of the property to parse 644 * @param prop_names name of the property containing the list of names 645 * @param name the name of the entry to look up 646 * @param res returns the resource 647 */ 648 int fdt_get_named_resource(const void *fdt, int node, const char *property, 649 const char *prop_names, const char *name, 650 struct fdt_resource *res); 651 652 #endif 653