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 COMPAT_MEMORY_SPD, /* Memory SPD information */ 123 COMPAT_INTEL_PANTHERPOINT_AHCI, /* Intel Pantherpoint AHCI */ 124 125 COMPAT_COUNT, 126 }; 127 128 /* GPIOs are numbered from 0 */ 129 enum { 130 FDT_GPIO_NONE = -1U, /* an invalid GPIO used to end our list */ 131 132 FDT_GPIO_ACTIVE_LOW = 1 << 0, /* input is active low (else high) */ 133 }; 134 135 /* This is the state of a GPIO pin as defined by the fdt */ 136 struct fdt_gpio_state { 137 const char *name; /* name of the fdt property defining this */ 138 uint gpio; /* GPIO number, or FDT_GPIO_NONE if none */ 139 u8 flags; /* FDT_GPIO_... flags */ 140 }; 141 142 /* This tells us whether a fdt_gpio_state record is valid or not */ 143 #define fdt_gpio_isvalid(x) ((x)->gpio != FDT_GPIO_NONE) 144 145 /** 146 * Read the GPIO taking into account the polarity of the pin. 147 * 148 * @param gpio pointer to the decoded gpio 149 * @return value of the gpio if successful, < 0 if unsuccessful 150 */ 151 int fdtdec_get_gpio(struct fdt_gpio_state *gpio); 152 153 /** 154 * Write the GPIO taking into account the polarity of the pin. 155 * 156 * @param gpio pointer to the decoded gpio 157 * @return 0 if successful 158 */ 159 int fdtdec_set_gpio(struct fdt_gpio_state *gpio, int val); 160 161 /** 162 * Find the next numbered alias for a peripheral. This is used to enumerate 163 * all the peripherals of a certain type. 164 * 165 * Do the first call with *upto = 0. Assuming /aliases/<name>0 exists then 166 * this function will return a pointer to the node the alias points to, and 167 * then update *upto to 1. Next time you call this function, the next node 168 * will be returned. 169 * 170 * All nodes returned will match the compatible ID, as it is assumed that 171 * all peripherals use the same driver. 172 * 173 * @param blob FDT blob to use 174 * @param name Root name of alias to search for 175 * @param id Compatible ID to look for 176 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more 177 */ 178 int fdtdec_next_alias(const void *blob, const char *name, 179 enum fdt_compat_id id, int *upto); 180 181 /** 182 * Find the compatible ID for a given node. 183 * 184 * Generally each node has at least one compatible string attached to it. 185 * This function looks through our list of known compatible strings and 186 * returns the corresponding ID which matches the compatible string. 187 * 188 * @param blob FDT blob to use 189 * @param node Node containing compatible string to find 190 * @return compatible ID, or COMPAT_UNKNOWN if we cannot find a match 191 */ 192 enum fdt_compat_id fdtdec_lookup(const void *blob, int node); 193 194 /** 195 * Find the next compatible node for a peripheral. 196 * 197 * Do the first call with node = 0. This function will return a pointer to 198 * the next compatible node. Next time you call this function, pass the 199 * value returned, and the next node will be provided. 200 * 201 * @param blob FDT blob to use 202 * @param node Start node for search 203 * @param id Compatible ID to look for (enum fdt_compat_id) 204 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more 205 */ 206 int fdtdec_next_compatible(const void *blob, int node, 207 enum fdt_compat_id id); 208 209 /** 210 * Find the next compatible subnode for a peripheral. 211 * 212 * Do the first call with node set to the parent and depth = 0. This 213 * function will return the offset of the next compatible node. Next time 214 * you call this function, pass the node value returned last time, with 215 * depth unchanged, and the next node will be provided. 216 * 217 * @param blob FDT blob to use 218 * @param node Start node for search 219 * @param id Compatible ID to look for (enum fdt_compat_id) 220 * @param depthp Current depth (set to 0 before first call) 221 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more 222 */ 223 int fdtdec_next_compatible_subnode(const void *blob, int node, 224 enum fdt_compat_id id, int *depthp); 225 226 /** 227 * Look up an address property in a node and return it as an address. 228 * The property must hold either one address with no trailing data or 229 * one address with a length. This is only tested on 32-bit machines. 230 * 231 * @param blob FDT blob 232 * @param node node to examine 233 * @param prop_name name of property to find 234 * @return address, if found, or FDT_ADDR_T_NONE if not 235 */ 236 fdt_addr_t fdtdec_get_addr(const void *blob, int node, 237 const char *prop_name); 238 239 /** 240 * Look up an address property in a node and return it as an address. 241 * The property must hold one address with a length. This is only tested 242 * on 32-bit machines. 243 * 244 * @param blob FDT blob 245 * @param node node to examine 246 * @param prop_name name of property to find 247 * @return address, if found, or FDT_ADDR_T_NONE if not 248 */ 249 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node, 250 const char *prop_name, fdt_size_t *sizep); 251 252 /** 253 * Look up a 32-bit integer property in a node and return it. The property 254 * must have at least 4 bytes of data. The value of the first cell is 255 * returned. 256 * 257 * @param blob FDT blob 258 * @param node node to examine 259 * @param prop_name name of property to find 260 * @param default_val default value to return if the property is not found 261 * @return integer value, if found, or default_val if not 262 */ 263 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name, 264 s32 default_val); 265 266 /** 267 * Look up a 64-bit integer property in a node and return it. The property 268 * must have at least 8 bytes of data (2 cells). The first two cells are 269 * concatenated to form a 8 bytes value, where the first cell is top half and 270 * the second cell is bottom half. 271 * 272 * @param blob FDT blob 273 * @param node node to examine 274 * @param prop_name name of property to find 275 * @param default_val default value to return if the property is not found 276 * @return integer value, if found, or default_val if not 277 */ 278 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name, 279 uint64_t default_val); 280 281 /** 282 * Checks whether a node is enabled. 283 * This looks for a 'status' property. If this exists, then returns 1 if 284 * the status is 'ok' and 0 otherwise. If there is no status property, 285 * it returns 1 on the assumption that anything mentioned should be enabled 286 * by default. 287 * 288 * @param blob FDT blob 289 * @param node node to examine 290 * @return integer value 0 (not enabled) or 1 (enabled) 291 */ 292 int fdtdec_get_is_enabled(const void *blob, int node); 293 294 /** 295 * Make sure we have a valid fdt available to control U-Boot. 296 * 297 * If not, a message is printed to the console if the console is ready. 298 * 299 * @return 0 if all ok, -1 if not 300 */ 301 int fdtdec_prepare_fdt(void); 302 303 /** 304 * Checks that we have a valid fdt available to control U-Boot. 305 306 * However, if not then for the moment nothing is done, since this function 307 * is called too early to panic(). 308 * 309 * @returns 0 310 */ 311 int fdtdec_check_fdt(void); 312 313 /** 314 * Find the nodes for a peripheral and return a list of them in the correct 315 * order. This is used to enumerate all the peripherals of a certain type. 316 * 317 * To use this, optionally set up a /aliases node with alias properties for 318 * a peripheral. For example, for usb you could have: 319 * 320 * aliases { 321 * usb0 = "/ehci@c5008000"; 322 * usb1 = "/ehci@c5000000"; 323 * }; 324 * 325 * Pass "usb" as the name to this function and will return a list of two 326 * nodes offsets: /ehci@c5008000 and ehci@c5000000. 327 * 328 * All nodes returned will match the compatible ID, as it is assumed that 329 * all peripherals use the same driver. 330 * 331 * If no alias node is found, then the node list will be returned in the 332 * order found in the fdt. If the aliases mention a node which doesn't 333 * exist, then this will be ignored. If nodes are found with no aliases, 334 * they will be added in any order. 335 * 336 * If there is a gap in the aliases, then this function return a 0 node at 337 * that position. The return value will also count these gaps. 338 * 339 * This function checks node properties and will not return nodes which are 340 * marked disabled (status = "disabled"). 341 * 342 * @param blob FDT blob to use 343 * @param name Root name of alias to search for 344 * @param id Compatible ID to look for 345 * @param node_list Place to put list of found nodes 346 * @param maxcount Maximum number of nodes to find 347 * @return number of nodes found on success, FTD_ERR_... on error 348 */ 349 int fdtdec_find_aliases_for_id(const void *blob, const char *name, 350 enum fdt_compat_id id, int *node_list, int maxcount); 351 352 /* 353 * This function is similar to fdtdec_find_aliases_for_id() except that it 354 * adds to the node_list that is passed in. Any 0 elements are considered 355 * available for allocation - others are considered already used and are 356 * skipped. 357 * 358 * You can use this by calling fdtdec_find_aliases_for_id() with an 359 * uninitialised array, then setting the elements that are returned to -1, 360 * say, then calling this function, perhaps with a different compat id. 361 * Any elements you get back that are >0 are new nodes added by the call 362 * to this function. 363 * 364 * Note that if you have some nodes with aliases and some without, you are 365 * sailing close to the wind. The call to fdtdec_find_aliases_for_id() with 366 * one compat_id may fill in positions for which you have aliases defined 367 * for another compat_id. When you later call *this* function with the second 368 * compat_id, the alias positions may already be used. A debug warning may 369 * be generated in this case, but it is safest to define aliases for all 370 * nodes when you care about the ordering. 371 */ 372 int fdtdec_add_aliases_for_id(const void *blob, const char *name, 373 enum fdt_compat_id id, int *node_list, int maxcount); 374 375 /** 376 * Get the alias sequence number of a node 377 * 378 * This works out whether a node is pointed to by an alias, and if so, the 379 * sequence number of that alias. Aliases are of the form <base><num> where 380 * <num> is the sequence number. For example spi2 would be sequence number 381 * 2. 382 * 383 * @param blob Device tree blob (if NULL, then error is returned) 384 * @param base Base name for alias (before the underscore) 385 * @param node Node to look up 386 * @param seqp This is set to the sequence number if one is found, 387 * but otherwise the value is left alone 388 * @return 0 if a sequence was found, -ve if not 389 */ 390 int fdtdec_get_alias_seq(const void *blob, const char *base, int node, 391 int *seqp); 392 393 /** 394 * Get the offset of the given alias node 395 * 396 * This looks up an alias in /aliases then finds the offset of that node. 397 * 398 * @param blob Device tree blob (if NULL, then error is returned) 399 * @param name Alias name, e.g. "console" 400 * @return Node offset referred to by that alias, or -ve FDT_ERR_... 401 */ 402 int fdtdec_get_alias_node(const void *blob, const char *name); 403 404 /** 405 * Get the offset of the given chosen node 406 * 407 * This looks up a property in /chosen containing the path to another node, 408 * then finds the offset of that node. 409 * 410 * @param blob Device tree blob (if NULL, then error is returned) 411 * @param name Property name, e.g. "stdout-path" 412 * @return Node offset referred to by that chosen node, or -ve FDT_ERR_... 413 */ 414 int fdtdec_get_chosen_node(const void *blob, const char *name); 415 416 /* 417 * Get the name for a compatible ID 418 * 419 * @param id Compatible ID to look for 420 * @return compatible string for that id 421 */ 422 const char *fdtdec_get_compatible(enum fdt_compat_id id); 423 424 /* Look up a phandle and follow it to its node. Then return the offset 425 * of that node. 426 * 427 * @param blob FDT blob 428 * @param node node to examine 429 * @param prop_name name of property to find 430 * @return node offset if found, -ve error code on error 431 */ 432 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name); 433 434 /** 435 * Look up a property in a node and return its contents in an integer 436 * array of given length. The property must have at least enough data for 437 * the array (4*count bytes). It may have more, but this will be ignored. 438 * 439 * @param blob FDT blob 440 * @param node node to examine 441 * @param prop_name name of property to find 442 * @param array array to fill with data 443 * @param count number of array elements 444 * @return 0 if ok, or -FDT_ERR_NOTFOUND if the property is not found, 445 * or -FDT_ERR_BADLAYOUT if not enough data 446 */ 447 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name, 448 u32 *array, int count); 449 450 /** 451 * Look up a property in a node and return its contents in an integer 452 * array of given length. The property must exist but may have less data that 453 * expected (4*count bytes). It may have more, but this will be ignored. 454 * 455 * @param blob FDT blob 456 * @param node node to examine 457 * @param prop_name name of property to find 458 * @param array array to fill with data 459 * @param count number of array elements 460 * @return number of array elements if ok, or -FDT_ERR_NOTFOUND if the 461 * property is not found 462 */ 463 int fdtdec_get_int_array_count(const void *blob, int node, 464 const char *prop_name, u32 *array, int count); 465 466 /** 467 * Look up a property in a node and return a pointer to its contents as a 468 * unsigned int array of given length. The property must have at least enough 469 * data for the array ('count' cells). It may have more, but this will be 470 * ignored. The data is not copied. 471 * 472 * Note that you must access elements of the array with fdt32_to_cpu(), 473 * since the elements will be big endian even on a little endian machine. 474 * 475 * @param blob FDT blob 476 * @param node node to examine 477 * @param prop_name name of property to find 478 * @param count number of array elements 479 * @return pointer to array if found, or NULL if the property is not 480 * found or there is not enough data 481 */ 482 const u32 *fdtdec_locate_array(const void *blob, int node, 483 const char *prop_name, int count); 484 485 /** 486 * Look up a boolean property in a node and return it. 487 * 488 * A boolean properly is true if present in the device tree and false if not 489 * present, regardless of its value. 490 * 491 * @param blob FDT blob 492 * @param node node to examine 493 * @param prop_name name of property to find 494 * @return 1 if the properly is present; 0 if it isn't present 495 */ 496 int fdtdec_get_bool(const void *blob, int node, const char *prop_name); 497 498 /** 499 * Decode a single GPIOs from an FDT. 500 * 501 * If the property is not found, then the GPIO structure will still be 502 * initialised, with gpio set to FDT_GPIO_NONE. This makes it easy to 503 * provide optional GPIOs. 504 * 505 * @param blob FDT blob to use 506 * @param node Node to look at 507 * @param prop_name Node property name 508 * @param gpio gpio elements to fill from FDT 509 * @return 0 if ok, -FDT_ERR_NOTFOUND if the property is missing. 510 */ 511 int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name, 512 struct fdt_gpio_state *gpio); 513 514 /** 515 * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no 516 * terminating item. 517 * 518 * @param blob FDT blob to use 519 * @param node Node to look at 520 * @param prop_name Node property name 521 * @param gpio Array of gpio elements to fill from FDT. This will be 522 * untouched if either 0 or an error is returned 523 * @param max_count Maximum number of elements allowed 524 * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would 525 * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing. 526 */ 527 int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name, 528 struct fdt_gpio_state *gpio, int max_count); 529 530 /** 531 * Set up a GPIO pin according to the provided gpio information. At present this 532 * just requests the GPIO. 533 * 534 * If the gpio is FDT_GPIO_NONE, no action is taken. This makes it easy to 535 * deal with optional GPIOs. 536 * 537 * @param gpio GPIO info to use for set up 538 * @return 0 if all ok or gpio was FDT_GPIO_NONE; -1 on error 539 */ 540 int fdtdec_setup_gpio(struct fdt_gpio_state *gpio); 541 542 /** 543 * Look in the FDT for a config item with the given name and return its value 544 * as a 32-bit integer. The property must have at least 4 bytes of data. The 545 * value of the first cell is returned. 546 * 547 * @param blob FDT blob to use 548 * @param prop_name Node property name 549 * @param default_val default value to return if the property is not found 550 * @return integer value, if found, or default_val if not 551 */ 552 int fdtdec_get_config_int(const void *blob, const char *prop_name, 553 int default_val); 554 555 /** 556 * Look in the FDT for a config item with the given name 557 * and return whether it exists. 558 * 559 * @param blob FDT blob 560 * @param prop_name property name to look up 561 * @return 1, if it exists, or 0 if not 562 */ 563 int fdtdec_get_config_bool(const void *blob, const char *prop_name); 564 565 /** 566 * Look in the FDT for a config item with the given name and return its value 567 * as a string. 568 * 569 * @param blob FDT blob 570 * @param prop_name property name to look up 571 * @returns property string, NULL on error. 572 */ 573 char *fdtdec_get_config_string(const void *blob, const char *prop_name); 574 575 /* 576 * Look up a property in a node and return its contents in a byte 577 * array of given length. The property must have at least enough data for 578 * the array (count bytes). It may have more, but this will be ignored. 579 * 580 * @param blob FDT blob 581 * @param node node to examine 582 * @param prop_name name of property to find 583 * @param array array to fill with data 584 * @param count number of array elements 585 * @return 0 if ok, or -FDT_ERR_MISSING if the property is not found, 586 * or -FDT_ERR_BADLAYOUT if not enough data 587 */ 588 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name, 589 u8 *array, int count); 590 591 /** 592 * Look up a property in a node and return a pointer to its contents as a 593 * byte array of given length. The property must have at least enough data 594 * for the array (count bytes). It may have more, but this will be ignored. 595 * The data is not copied. 596 * 597 * @param blob FDT blob 598 * @param node node to examine 599 * @param prop_name name of property to find 600 * @param count number of array elements 601 * @return pointer to byte array if found, or NULL if the property is not 602 * found or there is not enough data 603 */ 604 const u8 *fdtdec_locate_byte_array(const void *blob, int node, 605 const char *prop_name, int count); 606 607 /** 608 * Look up a property in a node which contains a memory region address and 609 * size. Then return a pointer to this address. 610 * 611 * The property must hold one address with a length. This is only tested on 612 * 32-bit machines. 613 * 614 * @param blob FDT blob 615 * @param node node to examine 616 * @param prop_name name of property to find 617 * @param ptrp returns pointer to region, or NULL if no address 618 * @param size returns size of region 619 * @return 0 if ok, -1 on error (propery not found) 620 */ 621 int fdtdec_decode_region(const void *blob, int node, 622 const char *prop_name, void **ptrp, size_t *size); 623 624 /* A flash map entry, containing an offset and length */ 625 struct fmap_entry { 626 uint32_t offset; 627 uint32_t length; 628 }; 629 630 /** 631 * Read a flash entry from the fdt 632 * 633 * @param blob FDT blob 634 * @param node Offset of node to read 635 * @param name Name of node being read 636 * @param entry Place to put offset and size of this node 637 * @return 0 if ok, -ve on error 638 */ 639 int fdtdec_read_fmap_entry(const void *blob, int node, const char *name, 640 struct fmap_entry *entry); 641 642 /** 643 * Obtain an indexed resource from a device property. 644 * 645 * @param fdt FDT blob 646 * @param node node to examine 647 * @param property name of the property to parse 648 * @param index index of the resource to retrieve 649 * @param res returns the resource 650 * @return 0 if ok, negative on error 651 */ 652 int fdt_get_resource(const void *fdt, int node, const char *property, 653 unsigned int index, struct fdt_resource *res); 654 655 /** 656 * Obtain a named resource from a device property. 657 * 658 * Look up the index of the name in a list of strings and return the resource 659 * at that index. 660 * 661 * @param fdt FDT blob 662 * @param node node to examine 663 * @param property name of the property to parse 664 * @param prop_names name of the property containing the list of names 665 * @param name the name of the entry to look up 666 * @param res returns the resource 667 */ 668 int fdt_get_named_resource(const void *fdt, int node, const char *property, 669 const char *prop_names, const char *name, 670 struct fdt_resource *res); 671 672 /** 673 * Look at the reg property of a device node that represents a PCI device 674 * and parse the bus, device and function number from it. 675 * 676 * @param fdt FDT blob 677 * @param node node to examine 678 * @param bdf returns bus, device, function triplet 679 * @return 0 if ok, negative on error 680 */ 681 int fdtdec_pci_get_bdf(const void *fdt, int node, int *bdf); 682 683 #endif 684