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 COMPAT_INTEL_LPC, /* Intel Low Pin Count I/F */ 121 COMPAT_INTEL_MICROCODE, /* Intel microcode update */ 122 123 COMPAT_COUNT, 124 }; 125 126 /* GPIOs are numbered from 0 */ 127 enum { 128 FDT_GPIO_NONE = -1U, /* an invalid GPIO used to end our list */ 129 130 FDT_GPIO_ACTIVE_LOW = 1 << 0, /* input is active low (else high) */ 131 }; 132 133 /* This is the state of a GPIO pin as defined by the fdt */ 134 struct fdt_gpio_state { 135 const char *name; /* name of the fdt property defining this */ 136 uint gpio; /* GPIO number, or FDT_GPIO_NONE if none */ 137 u8 flags; /* FDT_GPIO_... flags */ 138 }; 139 140 /* This tells us whether a fdt_gpio_state record is valid or not */ 141 #define fdt_gpio_isvalid(x) ((x)->gpio != FDT_GPIO_NONE) 142 143 /** 144 * Read the GPIO taking into account the polarity of the pin. 145 * 146 * @param gpio pointer to the decoded gpio 147 * @return value of the gpio if successful, < 0 if unsuccessful 148 */ 149 int fdtdec_get_gpio(struct fdt_gpio_state *gpio); 150 151 /** 152 * Write the GPIO taking into account the polarity of the pin. 153 * 154 * @param gpio pointer to the decoded gpio 155 * @return 0 if successful 156 */ 157 int fdtdec_set_gpio(struct fdt_gpio_state *gpio, int val); 158 159 /** 160 * Find the next numbered alias for a peripheral. This is used to enumerate 161 * all the peripherals of a certain type. 162 * 163 * Do the first call with *upto = 0. Assuming /aliases/<name>0 exists then 164 * this function will return a pointer to the node the alias points to, and 165 * then update *upto to 1. Next time you call this function, the next node 166 * will be returned. 167 * 168 * All nodes returned will match the compatible ID, as it is assumed that 169 * all peripherals use the same driver. 170 * 171 * @param blob FDT blob to use 172 * @param name Root name of alias to search for 173 * @param id Compatible ID to look for 174 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more 175 */ 176 int fdtdec_next_alias(const void *blob, const char *name, 177 enum fdt_compat_id id, int *upto); 178 179 /** 180 * Find the compatible ID for a given node. 181 * 182 * Generally each node has at least one compatible string attached to it. 183 * This function looks through our list of known compatible strings and 184 * returns the corresponding ID which matches the compatible string. 185 * 186 * @param blob FDT blob to use 187 * @param node Node containing compatible string to find 188 * @return compatible ID, or COMPAT_UNKNOWN if we cannot find a match 189 */ 190 enum fdt_compat_id fdtdec_lookup(const void *blob, int node); 191 192 /** 193 * Find the next compatible node for a peripheral. 194 * 195 * Do the first call with node = 0. This function will return a pointer to 196 * the next compatible node. Next time you call this function, pass the 197 * value returned, and the next node will be provided. 198 * 199 * @param blob FDT blob to use 200 * @param node Start node for search 201 * @param id Compatible ID to look for (enum fdt_compat_id) 202 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more 203 */ 204 int fdtdec_next_compatible(const void *blob, int node, 205 enum fdt_compat_id id); 206 207 /** 208 * Find the next compatible subnode for a peripheral. 209 * 210 * Do the first call with node set to the parent and depth = 0. This 211 * function will return the offset of the next compatible node. Next time 212 * you call this function, pass the node value returned last time, with 213 * depth unchanged, and the next node will be provided. 214 * 215 * @param blob FDT blob to use 216 * @param node Start node for search 217 * @param id Compatible ID to look for (enum fdt_compat_id) 218 * @param depthp Current depth (set to 0 before first call) 219 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more 220 */ 221 int fdtdec_next_compatible_subnode(const void *blob, int node, 222 enum fdt_compat_id id, int *depthp); 223 224 /** 225 * Look up an address property in a node and return it as an address. 226 * The property must hold either one address with no trailing data or 227 * one address with a length. This is only tested on 32-bit machines. 228 * 229 * @param blob FDT blob 230 * @param node node to examine 231 * @param prop_name name of property to find 232 * @return address, if found, or FDT_ADDR_T_NONE if not 233 */ 234 fdt_addr_t fdtdec_get_addr(const void *blob, int node, 235 const char *prop_name); 236 237 /** 238 * Look up an address property in a node and return it as an address. 239 * The property must hold one address with a length. This is only tested 240 * on 32-bit machines. 241 * 242 * @param blob FDT blob 243 * @param node node to examine 244 * @param prop_name name of property to find 245 * @return address, if found, or FDT_ADDR_T_NONE if not 246 */ 247 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node, 248 const char *prop_name, fdt_size_t *sizep); 249 250 /** 251 * Look up a 32-bit integer property in a node and return it. The property 252 * must have at least 4 bytes of data. The value of the first cell is 253 * returned. 254 * 255 * @param blob FDT blob 256 * @param node node to examine 257 * @param prop_name name of property to find 258 * @param default_val default value to return if the property is not found 259 * @return integer value, if found, or default_val if not 260 */ 261 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name, 262 s32 default_val); 263 264 /** 265 * Look up a 64-bit integer property in a node and return it. The property 266 * must have at least 8 bytes of data (2 cells). The first two cells are 267 * concatenated to form a 8 bytes value, where the first cell is top half and 268 * the second cell is bottom half. 269 * 270 * @param blob FDT blob 271 * @param node node to examine 272 * @param prop_name name of property to find 273 * @param default_val default value to return if the property is not found 274 * @return integer value, if found, or default_val if not 275 */ 276 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name, 277 uint64_t default_val); 278 279 /** 280 * Checks whether a node is enabled. 281 * This looks for a 'status' property. If this exists, then returns 1 if 282 * the status is 'ok' and 0 otherwise. If there is no status property, 283 * it returns 1 on the assumption that anything mentioned should be enabled 284 * by default. 285 * 286 * @param blob FDT blob 287 * @param node node to examine 288 * @return integer value 0 (not enabled) or 1 (enabled) 289 */ 290 int fdtdec_get_is_enabled(const void *blob, int node); 291 292 /** 293 * Make sure we have a valid fdt available to control U-Boot. 294 * 295 * If not, a message is printed to the console if the console is ready. 296 * 297 * @return 0 if all ok, -1 if not 298 */ 299 int fdtdec_prepare_fdt(void); 300 301 /** 302 * Checks that we have a valid fdt available to control U-Boot. 303 304 * However, if not then for the moment nothing is done, since this function 305 * is called too early to panic(). 306 * 307 * @returns 0 308 */ 309 int fdtdec_check_fdt(void); 310 311 /** 312 * Find the nodes for a peripheral and return a list of them in the correct 313 * order. This is used to enumerate all the peripherals of a certain type. 314 * 315 * To use this, optionally set up a /aliases node with alias properties for 316 * a peripheral. For example, for usb you could have: 317 * 318 * aliases { 319 * usb0 = "/ehci@c5008000"; 320 * usb1 = "/ehci@c5000000"; 321 * }; 322 * 323 * Pass "usb" as the name to this function and will return a list of two 324 * nodes offsets: /ehci@c5008000 and ehci@c5000000. 325 * 326 * All nodes returned will match the compatible ID, as it is assumed that 327 * all peripherals use the same driver. 328 * 329 * If no alias node is found, then the node list will be returned in the 330 * order found in the fdt. If the aliases mention a node which doesn't 331 * exist, then this will be ignored. If nodes are found with no aliases, 332 * they will be added in any order. 333 * 334 * If there is a gap in the aliases, then this function return a 0 node at 335 * that position. The return value will also count these gaps. 336 * 337 * This function checks node properties and will not return nodes which are 338 * marked disabled (status = "disabled"). 339 * 340 * @param blob FDT blob to use 341 * @param name Root name of alias to search for 342 * @param id Compatible ID to look for 343 * @param node_list Place to put list of found nodes 344 * @param maxcount Maximum number of nodes to find 345 * @return number of nodes found on success, FTD_ERR_... on error 346 */ 347 int fdtdec_find_aliases_for_id(const void *blob, const char *name, 348 enum fdt_compat_id id, int *node_list, int maxcount); 349 350 /* 351 * This function is similar to fdtdec_find_aliases_for_id() except that it 352 * adds to the node_list that is passed in. Any 0 elements are considered 353 * available for allocation - others are considered already used and are 354 * skipped. 355 * 356 * You can use this by calling fdtdec_find_aliases_for_id() with an 357 * uninitialised array, then setting the elements that are returned to -1, 358 * say, then calling this function, perhaps with a different compat id. 359 * Any elements you get back that are >0 are new nodes added by the call 360 * to this function. 361 * 362 * Note that if you have some nodes with aliases and some without, you are 363 * sailing close to the wind. The call to fdtdec_find_aliases_for_id() with 364 * one compat_id may fill in positions for which you have aliases defined 365 * for another compat_id. When you later call *this* function with the second 366 * compat_id, the alias positions may already be used. A debug warning may 367 * be generated in this case, but it is safest to define aliases for all 368 * nodes when you care about the ordering. 369 */ 370 int fdtdec_add_aliases_for_id(const void *blob, const char *name, 371 enum fdt_compat_id id, int *node_list, int maxcount); 372 373 /** 374 * Get the alias sequence number of a node 375 * 376 * This works out whether a node is pointed to by an alias, and if so, the 377 * sequence number of that alias. Aliases are of the form <base><num> where 378 * <num> is the sequence number. For example spi2 would be sequence number 379 * 2. 380 * 381 * @param blob Device tree blob (if NULL, then error is returned) 382 * @param base Base name for alias (before the underscore) 383 * @param node Node to look up 384 * @param seqp This is set to the sequence number if one is found, 385 * but otherwise the value is left alone 386 * @return 0 if a sequence was found, -ve if not 387 */ 388 int fdtdec_get_alias_seq(const void *blob, const char *base, int node, 389 int *seqp); 390 391 /** 392 * Get the offset of the given alias node 393 * 394 * This looks up an alias in /aliases then finds the offset of that node. 395 * 396 * @param blob Device tree blob (if NULL, then error is returned) 397 * @param name Alias name, e.g. "console" 398 * @return Node offset referred to by that alias, or -ve FDT_ERR_... 399 */ 400 int fdtdec_get_alias_node(const void *blob, const char *name); 401 402 /** 403 * Get the offset of the given chosen node 404 * 405 * This looks up a property in /chosen containing the path to another node, 406 * then finds the offset of that node. 407 * 408 * @param blob Device tree blob (if NULL, then error is returned) 409 * @param name Property name, e.g. "stdout-path" 410 * @return Node offset referred to by that chosen node, or -ve FDT_ERR_... 411 */ 412 int fdtdec_get_chosen_node(const void *blob, const char *name); 413 414 /* 415 * Get the name for a compatible ID 416 * 417 * @param id Compatible ID to look for 418 * @return compatible string for that id 419 */ 420 const char *fdtdec_get_compatible(enum fdt_compat_id id); 421 422 /* Look up a phandle and follow it to its node. Then return the offset 423 * of that node. 424 * 425 * @param blob FDT blob 426 * @param node node to examine 427 * @param prop_name name of property to find 428 * @return node offset if found, -ve error code on error 429 */ 430 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name); 431 432 /** 433 * Look up a property in a node and return its contents in an integer 434 * array of given length. The property must have at least enough data for 435 * the array (4*count bytes). It may have more, but this will be ignored. 436 * 437 * @param blob FDT blob 438 * @param node node to examine 439 * @param prop_name name of property to find 440 * @param array array to fill with data 441 * @param count number of array elements 442 * @return 0 if ok, or -FDT_ERR_NOTFOUND if the property is not found, 443 * or -FDT_ERR_BADLAYOUT if not enough data 444 */ 445 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name, 446 u32 *array, int count); 447 448 /** 449 * Look up a property in a node and return its contents in an integer 450 * array of given length. The property must exist but may have less data that 451 * expected (4*count bytes). It may have more, but this will be ignored. 452 * 453 * @param blob FDT blob 454 * @param node node to examine 455 * @param prop_name name of property to find 456 * @param array array to fill with data 457 * @param count number of array elements 458 * @return number of array elements if ok, or -FDT_ERR_NOTFOUND if the 459 * property is not found 460 */ 461 int fdtdec_get_int_array_count(const void *blob, int node, 462 const char *prop_name, u32 *array, int count); 463 464 /** 465 * Look up a property in a node and return a pointer to its contents as a 466 * unsigned int array of given length. The property must have at least enough 467 * data for the array ('count' cells). It may have more, but this will be 468 * ignored. The data is not copied. 469 * 470 * Note that you must access elements of the array with fdt32_to_cpu(), 471 * since the elements will be big endian even on a little endian machine. 472 * 473 * @param blob FDT blob 474 * @param node node to examine 475 * @param prop_name name of property to find 476 * @param count number of array elements 477 * @return pointer to array if found, or NULL if the property is not 478 * found or there is not enough data 479 */ 480 const u32 *fdtdec_locate_array(const void *blob, int node, 481 const char *prop_name, int count); 482 483 /** 484 * Look up a boolean property in a node and return it. 485 * 486 * A boolean properly is true if present in the device tree and false if not 487 * present, regardless of its value. 488 * 489 * @param blob FDT blob 490 * @param node node to examine 491 * @param prop_name name of property to find 492 * @return 1 if the properly is present; 0 if it isn't present 493 */ 494 int fdtdec_get_bool(const void *blob, int node, const char *prop_name); 495 496 /** 497 * Decode a single GPIOs from an FDT. 498 * 499 * If the property is not found, then the GPIO structure will still be 500 * initialised, with gpio set to FDT_GPIO_NONE. This makes it easy to 501 * provide optional GPIOs. 502 * 503 * @param blob FDT blob to use 504 * @param node Node to look at 505 * @param prop_name Node property name 506 * @param gpio gpio elements to fill from FDT 507 * @return 0 if ok, -FDT_ERR_NOTFOUND if the property is missing. 508 */ 509 int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name, 510 struct fdt_gpio_state *gpio); 511 512 /** 513 * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no 514 * terminating item. 515 * 516 * @param blob FDT blob to use 517 * @param node Node to look at 518 * @param prop_name Node property name 519 * @param gpio Array of gpio elements to fill from FDT. This will be 520 * untouched if either 0 or an error is returned 521 * @param max_count Maximum number of elements allowed 522 * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would 523 * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing. 524 */ 525 int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name, 526 struct fdt_gpio_state *gpio, int max_count); 527 528 /** 529 * Set up a GPIO pin according to the provided gpio information. At present this 530 * just requests the GPIO. 531 * 532 * If the gpio is FDT_GPIO_NONE, no action is taken. This makes it easy to 533 * deal with optional GPIOs. 534 * 535 * @param gpio GPIO info to use for set up 536 * @return 0 if all ok or gpio was FDT_GPIO_NONE; -1 on error 537 */ 538 int fdtdec_setup_gpio(struct fdt_gpio_state *gpio); 539 540 /** 541 * Look in the FDT for a config item with the given name and return its value 542 * as a 32-bit integer. The property must have at least 4 bytes of data. The 543 * value of the first cell is returned. 544 * 545 * @param blob FDT blob to use 546 * @param prop_name Node property name 547 * @param default_val default value to return if the property is not found 548 * @return integer value, if found, or default_val if not 549 */ 550 int fdtdec_get_config_int(const void *blob, const char *prop_name, 551 int default_val); 552 553 /** 554 * Look in the FDT for a config item with the given name 555 * and return whether it exists. 556 * 557 * @param blob FDT blob 558 * @param prop_name property name to look up 559 * @return 1, if it exists, or 0 if not 560 */ 561 int fdtdec_get_config_bool(const void *blob, const char *prop_name); 562 563 /** 564 * Look in the FDT for a config item with the given name and return its value 565 * as a string. 566 * 567 * @param blob FDT blob 568 * @param prop_name property name to look up 569 * @returns property string, NULL on error. 570 */ 571 char *fdtdec_get_config_string(const void *blob, const char *prop_name); 572 573 /* 574 * Look up a property in a node and return its contents in a byte 575 * array of given length. The property must have at least enough data for 576 * the array (count bytes). It may have more, but this will be ignored. 577 * 578 * @param blob FDT blob 579 * @param node node to examine 580 * @param prop_name name of property to find 581 * @param array array to fill with data 582 * @param count number of array elements 583 * @return 0 if ok, or -FDT_ERR_MISSING if the property is not found, 584 * or -FDT_ERR_BADLAYOUT if not enough data 585 */ 586 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name, 587 u8 *array, int count); 588 589 /** 590 * Look up a property in a node and return a pointer to its contents as a 591 * byte array of given length. The property must have at least enough data 592 * for the array (count bytes). It may have more, but this will be ignored. 593 * The data is not copied. 594 * 595 * @param blob FDT blob 596 * @param node node to examine 597 * @param prop_name name of property to find 598 * @param count number of array elements 599 * @return pointer to byte array if found, or NULL if the property is not 600 * found or there is not enough data 601 */ 602 const u8 *fdtdec_locate_byte_array(const void *blob, int node, 603 const char *prop_name, int count); 604 605 /** 606 * Look up a property in a node which contains a memory region address and 607 * size. Then return a pointer to this address. 608 * 609 * The property must hold one address with a length. This is only tested on 610 * 32-bit machines. 611 * 612 * @param blob FDT blob 613 * @param node node to examine 614 * @param prop_name name of property to find 615 * @param ptrp returns pointer to region, or NULL if no address 616 * @param size returns size of region 617 * @return 0 if ok, -1 on error (propery not found) 618 */ 619 int fdtdec_decode_region(const void *blob, int node, 620 const char *prop_name, void **ptrp, size_t *size); 621 622 /* A flash map entry, containing an offset and length */ 623 struct fmap_entry { 624 uint32_t offset; 625 uint32_t length; 626 }; 627 628 /** 629 * Read a flash entry from the fdt 630 * 631 * @param blob FDT blob 632 * @param node Offset of node to read 633 * @param name Name of node being read 634 * @param entry Place to put offset and size of this node 635 * @return 0 if ok, -ve on error 636 */ 637 int fdtdec_read_fmap_entry(const void *blob, int node, const char *name, 638 struct fmap_entry *entry); 639 640 /** 641 * Obtain an indexed resource from a device property. 642 * 643 * @param fdt FDT blob 644 * @param node node to examine 645 * @param property name of the property to parse 646 * @param index index of the resource to retrieve 647 * @param res returns the resource 648 * @return 0 if ok, negative on error 649 */ 650 int fdt_get_resource(const void *fdt, int node, const char *property, 651 unsigned int index, struct fdt_resource *res); 652 653 /** 654 * Obtain a named resource from a device property. 655 * 656 * Look up the index of the name in a list of strings and return the resource 657 * at that index. 658 * 659 * @param fdt FDT blob 660 * @param node node to examine 661 * @param property name of the property to parse 662 * @param prop_names name of the property containing the list of names 663 * @param name the name of the entry to look up 664 * @param res returns the resource 665 */ 666 int fdt_get_named_resource(const void *fdt, int node, const char *property, 667 const char *prop_names, const char *name, 668 struct fdt_resource *res); 669 670 /** 671 * Look at the reg property of a device node that represents a PCI device 672 * and parse the bus, device and function number from it. 673 * 674 * @param fdt FDT blob 675 * @param node node to examine 676 * @param bdf returns bus, device, function triplet 677 * @return 0 if ok, negative on error 678 */ 679 int fdtdec_pci_get_bdf(const void *fdt, int node, int *bdf); 680 681 #endif 682