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 COMPAT_INTEL_MODEL_206AX, /* Intel Model 206AX CPU */ 125 126 COMPAT_COUNT, 127 }; 128 129 /* GPIOs are numbered from 0 */ 130 enum { 131 FDT_GPIO_NONE = -1U, /* an invalid GPIO used to end our list */ 132 133 FDT_GPIO_ACTIVE_LOW = 1 << 0, /* input is active low (else high) */ 134 }; 135 136 /* This is the state of a GPIO pin as defined by the fdt */ 137 struct fdt_gpio_state { 138 const char *name; /* name of the fdt property defining this */ 139 uint gpio; /* GPIO number, or FDT_GPIO_NONE if none */ 140 u8 flags; /* FDT_GPIO_... flags */ 141 }; 142 143 /* This tells us whether a fdt_gpio_state record is valid or not */ 144 #define fdt_gpio_isvalid(x) ((x)->gpio != FDT_GPIO_NONE) 145 146 /** 147 * Read the GPIO taking into account the polarity of the pin. 148 * 149 * @param gpio pointer to the decoded gpio 150 * @return value of the gpio if successful, < 0 if unsuccessful 151 */ 152 int fdtdec_get_gpio(struct fdt_gpio_state *gpio); 153 154 /** 155 * Write the GPIO taking into account the polarity of the pin. 156 * 157 * @param gpio pointer to the decoded gpio 158 * @return 0 if successful 159 */ 160 int fdtdec_set_gpio(struct fdt_gpio_state *gpio, int val); 161 162 /** 163 * Find the next numbered alias for a peripheral. This is used to enumerate 164 * all the peripherals of a certain type. 165 * 166 * Do the first call with *upto = 0. Assuming /aliases/<name>0 exists then 167 * this function will return a pointer to the node the alias points to, and 168 * then update *upto to 1. Next time you call this function, the next node 169 * will be returned. 170 * 171 * All nodes returned will match the compatible ID, as it is assumed that 172 * all peripherals use the same driver. 173 * 174 * @param blob FDT blob to use 175 * @param name Root name of alias to search for 176 * @param id Compatible ID to look for 177 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more 178 */ 179 int fdtdec_next_alias(const void *blob, const char *name, 180 enum fdt_compat_id id, int *upto); 181 182 /** 183 * Find the compatible ID for a given node. 184 * 185 * Generally each node has at least one compatible string attached to it. 186 * This function looks through our list of known compatible strings and 187 * returns the corresponding ID which matches the compatible string. 188 * 189 * @param blob FDT blob to use 190 * @param node Node containing compatible string to find 191 * @return compatible ID, or COMPAT_UNKNOWN if we cannot find a match 192 */ 193 enum fdt_compat_id fdtdec_lookup(const void *blob, int node); 194 195 /** 196 * Find the next compatible node for a peripheral. 197 * 198 * Do the first call with node = 0. This function will return a pointer to 199 * the next compatible node. Next time you call this function, pass the 200 * value returned, and the next node will be provided. 201 * 202 * @param blob FDT blob to use 203 * @param node Start node for search 204 * @param id Compatible ID to look for (enum fdt_compat_id) 205 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more 206 */ 207 int fdtdec_next_compatible(const void *blob, int node, 208 enum fdt_compat_id id); 209 210 /** 211 * Find the next compatible subnode for a peripheral. 212 * 213 * Do the first call with node set to the parent and depth = 0. This 214 * function will return the offset of the next compatible node. Next time 215 * you call this function, pass the node value returned last time, with 216 * depth unchanged, and the next node will be provided. 217 * 218 * @param blob FDT blob to use 219 * @param node Start node for search 220 * @param id Compatible ID to look for (enum fdt_compat_id) 221 * @param depthp Current depth (set to 0 before first call) 222 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more 223 */ 224 int fdtdec_next_compatible_subnode(const void *blob, int node, 225 enum fdt_compat_id id, int *depthp); 226 227 /** 228 * Look up an address property in a node and return it as an address. 229 * The property must hold either one address with no trailing data or 230 * one address with a length. This is only tested on 32-bit machines. 231 * 232 * @param blob FDT blob 233 * @param node node to examine 234 * @param prop_name name of property to find 235 * @return address, if found, or FDT_ADDR_T_NONE if not 236 */ 237 fdt_addr_t fdtdec_get_addr(const void *blob, int node, 238 const char *prop_name); 239 240 /** 241 * Look up an address property in a node and return it as an address. 242 * The property must hold one address with a length. This is only tested 243 * on 32-bit machines. 244 * 245 * @param blob FDT blob 246 * @param node node to examine 247 * @param prop_name name of property to find 248 * @return address, if found, or FDT_ADDR_T_NONE if not 249 */ 250 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node, 251 const char *prop_name, fdt_size_t *sizep); 252 253 /** 254 * Look up a 32-bit integer property in a node and return it. The property 255 * must have at least 4 bytes of data. The value of the first cell is 256 * returned. 257 * 258 * @param blob FDT blob 259 * @param node node to examine 260 * @param prop_name name of property to find 261 * @param default_val default value to return if the property is not found 262 * @return integer value, if found, or default_val if not 263 */ 264 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name, 265 s32 default_val); 266 267 /** 268 * Look up a 64-bit integer property in a node and return it. The property 269 * must have at least 8 bytes of data (2 cells). The first two cells are 270 * concatenated to form a 8 bytes value, where the first cell is top half and 271 * the second cell is bottom half. 272 * 273 * @param blob FDT blob 274 * @param node node to examine 275 * @param prop_name name of property to find 276 * @param default_val default value to return if the property is not found 277 * @return integer value, if found, or default_val if not 278 */ 279 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name, 280 uint64_t default_val); 281 282 /** 283 * Checks whether a node is enabled. 284 * This looks for a 'status' property. If this exists, then returns 1 if 285 * the status is 'ok' and 0 otherwise. If there is no status property, 286 * it returns 1 on the assumption that anything mentioned should be enabled 287 * by default. 288 * 289 * @param blob FDT blob 290 * @param node node to examine 291 * @return integer value 0 (not enabled) or 1 (enabled) 292 */ 293 int fdtdec_get_is_enabled(const void *blob, int node); 294 295 /** 296 * Make sure we have a valid fdt available to control U-Boot. 297 * 298 * If not, a message is printed to the console if the console is ready. 299 * 300 * @return 0 if all ok, -1 if not 301 */ 302 int fdtdec_prepare_fdt(void); 303 304 /** 305 * Checks that we have a valid fdt available to control U-Boot. 306 307 * However, if not then for the moment nothing is done, since this function 308 * is called too early to panic(). 309 * 310 * @returns 0 311 */ 312 int fdtdec_check_fdt(void); 313 314 /** 315 * Find the nodes for a peripheral and return a list of them in the correct 316 * order. This is used to enumerate all the peripherals of a certain type. 317 * 318 * To use this, optionally set up a /aliases node with alias properties for 319 * a peripheral. For example, for usb you could have: 320 * 321 * aliases { 322 * usb0 = "/ehci@c5008000"; 323 * usb1 = "/ehci@c5000000"; 324 * }; 325 * 326 * Pass "usb" as the name to this function and will return a list of two 327 * nodes offsets: /ehci@c5008000 and ehci@c5000000. 328 * 329 * All nodes returned will match the compatible ID, as it is assumed that 330 * all peripherals use the same driver. 331 * 332 * If no alias node is found, then the node list will be returned in the 333 * order found in the fdt. If the aliases mention a node which doesn't 334 * exist, then this will be ignored. If nodes are found with no aliases, 335 * they will be added in any order. 336 * 337 * If there is a gap in the aliases, then this function return a 0 node at 338 * that position. The return value will also count these gaps. 339 * 340 * This function checks node properties and will not return nodes which are 341 * marked disabled (status = "disabled"). 342 * 343 * @param blob FDT blob to use 344 * @param name Root name of alias to search for 345 * @param id Compatible ID to look for 346 * @param node_list Place to put list of found nodes 347 * @param maxcount Maximum number of nodes to find 348 * @return number of nodes found on success, FTD_ERR_... on error 349 */ 350 int fdtdec_find_aliases_for_id(const void *blob, const char *name, 351 enum fdt_compat_id id, int *node_list, int maxcount); 352 353 /* 354 * This function is similar to fdtdec_find_aliases_for_id() except that it 355 * adds to the node_list that is passed in. Any 0 elements are considered 356 * available for allocation - others are considered already used and are 357 * skipped. 358 * 359 * You can use this by calling fdtdec_find_aliases_for_id() with an 360 * uninitialised array, then setting the elements that are returned to -1, 361 * say, then calling this function, perhaps with a different compat id. 362 * Any elements you get back that are >0 are new nodes added by the call 363 * to this function. 364 * 365 * Note that if you have some nodes with aliases and some without, you are 366 * sailing close to the wind. The call to fdtdec_find_aliases_for_id() with 367 * one compat_id may fill in positions for which you have aliases defined 368 * for another compat_id. When you later call *this* function with the second 369 * compat_id, the alias positions may already be used. A debug warning may 370 * be generated in this case, but it is safest to define aliases for all 371 * nodes when you care about the ordering. 372 */ 373 int fdtdec_add_aliases_for_id(const void *blob, const char *name, 374 enum fdt_compat_id id, int *node_list, int maxcount); 375 376 /** 377 * Get the alias sequence number of a node 378 * 379 * This works out whether a node is pointed to by an alias, and if so, the 380 * sequence number of that alias. Aliases are of the form <base><num> where 381 * <num> is the sequence number. For example spi2 would be sequence number 382 * 2. 383 * 384 * @param blob Device tree blob (if NULL, then error is returned) 385 * @param base Base name for alias (before the underscore) 386 * @param node Node to look up 387 * @param seqp This is set to the sequence number if one is found, 388 * but otherwise the value is left alone 389 * @return 0 if a sequence was found, -ve if not 390 */ 391 int fdtdec_get_alias_seq(const void *blob, const char *base, int node, 392 int *seqp); 393 394 /** 395 * Get the offset of the given alias node 396 * 397 * This looks up an alias in /aliases then finds the offset of that node. 398 * 399 * @param blob Device tree blob (if NULL, then error is returned) 400 * @param name Alias name, e.g. "console" 401 * @return Node offset referred to by that alias, or -ve FDT_ERR_... 402 */ 403 int fdtdec_get_alias_node(const void *blob, const char *name); 404 405 /** 406 * Get the offset of the given chosen node 407 * 408 * This looks up a property in /chosen containing the path to another node, 409 * then finds the offset of that node. 410 * 411 * @param blob Device tree blob (if NULL, then error is returned) 412 * @param name Property name, e.g. "stdout-path" 413 * @return Node offset referred to by that chosen node, or -ve FDT_ERR_... 414 */ 415 int fdtdec_get_chosen_node(const void *blob, const char *name); 416 417 /* 418 * Get the name for a compatible ID 419 * 420 * @param id Compatible ID to look for 421 * @return compatible string for that id 422 */ 423 const char *fdtdec_get_compatible(enum fdt_compat_id id); 424 425 /* Look up a phandle and follow it to its node. Then return the offset 426 * of that node. 427 * 428 * @param blob FDT blob 429 * @param node node to examine 430 * @param prop_name name of property to find 431 * @return node offset if found, -ve error code on error 432 */ 433 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name); 434 435 /** 436 * Look up a property in a node and return its contents in an integer 437 * array of given length. The property must have at least enough data for 438 * the array (4*count bytes). It may have more, but this will be ignored. 439 * 440 * @param blob FDT blob 441 * @param node node to examine 442 * @param prop_name name of property to find 443 * @param array array to fill with data 444 * @param count number of array elements 445 * @return 0 if ok, or -FDT_ERR_NOTFOUND if the property is not found, 446 * or -FDT_ERR_BADLAYOUT if not enough data 447 */ 448 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name, 449 u32 *array, int count); 450 451 /** 452 * Look up a property in a node and return its contents in an integer 453 * array of given length. The property must exist but may have less data that 454 * expected (4*count bytes). It may have more, but this will be ignored. 455 * 456 * @param blob FDT blob 457 * @param node node to examine 458 * @param prop_name name of property to find 459 * @param array array to fill with data 460 * @param count number of array elements 461 * @return number of array elements if ok, or -FDT_ERR_NOTFOUND if the 462 * property is not found 463 */ 464 int fdtdec_get_int_array_count(const void *blob, int node, 465 const char *prop_name, u32 *array, int count); 466 467 /** 468 * Look up a property in a node and return a pointer to its contents as a 469 * unsigned int array of given length. The property must have at least enough 470 * data for the array ('count' cells). It may have more, but this will be 471 * ignored. The data is not copied. 472 * 473 * Note that you must access elements of the array with fdt32_to_cpu(), 474 * since the elements will be big endian even on a little endian machine. 475 * 476 * @param blob FDT blob 477 * @param node node to examine 478 * @param prop_name name of property to find 479 * @param count number of array elements 480 * @return pointer to array if found, or NULL if the property is not 481 * found or there is not enough data 482 */ 483 const u32 *fdtdec_locate_array(const void *blob, int node, 484 const char *prop_name, int count); 485 486 /** 487 * Look up a boolean property in a node and return it. 488 * 489 * A boolean properly is true if present in the device tree and false if not 490 * present, regardless of its value. 491 * 492 * @param blob FDT blob 493 * @param node node to examine 494 * @param prop_name name of property to find 495 * @return 1 if the properly is present; 0 if it isn't present 496 */ 497 int fdtdec_get_bool(const void *blob, int node, const char *prop_name); 498 499 /** 500 * Decode a single GPIOs from an FDT. 501 * 502 * If the property is not found, then the GPIO structure will still be 503 * initialised, with gpio set to FDT_GPIO_NONE. This makes it easy to 504 * provide optional GPIOs. 505 * 506 * @param blob FDT blob to use 507 * @param node Node to look at 508 * @param prop_name Node property name 509 * @param gpio gpio elements to fill from FDT 510 * @return 0 if ok, -FDT_ERR_NOTFOUND if the property is missing. 511 */ 512 int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name, 513 struct fdt_gpio_state *gpio); 514 515 /** 516 * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no 517 * terminating item. 518 * 519 * @param blob FDT blob to use 520 * @param node Node to look at 521 * @param prop_name Node property name 522 * @param gpio Array of gpio elements to fill from FDT. This will be 523 * untouched if either 0 or an error is returned 524 * @param max_count Maximum number of elements allowed 525 * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would 526 * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing. 527 */ 528 int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name, 529 struct fdt_gpio_state *gpio, int max_count); 530 531 /** 532 * Set up a GPIO pin according to the provided gpio information. At present this 533 * just requests the GPIO. 534 * 535 * If the gpio is FDT_GPIO_NONE, no action is taken. This makes it easy to 536 * deal with optional GPIOs. 537 * 538 * @param gpio GPIO info to use for set up 539 * @return 0 if all ok or gpio was FDT_GPIO_NONE; -1 on error 540 */ 541 int fdtdec_setup_gpio(struct fdt_gpio_state *gpio); 542 543 /** 544 * Look in the FDT for a config item with the given name and return its value 545 * as a 32-bit integer. The property must have at least 4 bytes of data. The 546 * value of the first cell is returned. 547 * 548 * @param blob FDT blob to use 549 * @param prop_name Node property name 550 * @param default_val default value to return if the property is not found 551 * @return integer value, if found, or default_val if not 552 */ 553 int fdtdec_get_config_int(const void *blob, const char *prop_name, 554 int default_val); 555 556 /** 557 * Look in the FDT for a config item with the given name 558 * and return whether it exists. 559 * 560 * @param blob FDT blob 561 * @param prop_name property name to look up 562 * @return 1, if it exists, or 0 if not 563 */ 564 int fdtdec_get_config_bool(const void *blob, const char *prop_name); 565 566 /** 567 * Look in the FDT for a config item with the given name and return its value 568 * as a string. 569 * 570 * @param blob FDT blob 571 * @param prop_name property name to look up 572 * @returns property string, NULL on error. 573 */ 574 char *fdtdec_get_config_string(const void *blob, const char *prop_name); 575 576 /* 577 * Look up a property in a node and return its contents in a byte 578 * array of given length. The property must have at least enough data for 579 * the array (count bytes). It may have more, but this will be ignored. 580 * 581 * @param blob FDT blob 582 * @param node node to examine 583 * @param prop_name name of property to find 584 * @param array array to fill with data 585 * @param count number of array elements 586 * @return 0 if ok, or -FDT_ERR_MISSING if the property is not found, 587 * or -FDT_ERR_BADLAYOUT if not enough data 588 */ 589 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name, 590 u8 *array, int count); 591 592 /** 593 * Look up a property in a node and return a pointer to its contents as a 594 * byte array of given length. The property must have at least enough data 595 * for the array (count bytes). It may have more, but this will be ignored. 596 * The data is not copied. 597 * 598 * @param blob FDT blob 599 * @param node node to examine 600 * @param prop_name name of property to find 601 * @param count number of array elements 602 * @return pointer to byte array if found, or NULL if the property is not 603 * found or there is not enough data 604 */ 605 const u8 *fdtdec_locate_byte_array(const void *blob, int node, 606 const char *prop_name, int count); 607 608 /** 609 * Look up a property in a node which contains a memory region address and 610 * size. Then return a pointer to this address. 611 * 612 * The property must hold one address with a length. This is only tested on 613 * 32-bit machines. 614 * 615 * @param blob FDT blob 616 * @param node node to examine 617 * @param prop_name name of property to find 618 * @param ptrp returns pointer to region, or NULL if no address 619 * @param size returns size of region 620 * @return 0 if ok, -1 on error (propery not found) 621 */ 622 int fdtdec_decode_region(const void *blob, int node, 623 const char *prop_name, void **ptrp, size_t *size); 624 625 /* A flash map entry, containing an offset and length */ 626 struct fmap_entry { 627 uint32_t offset; 628 uint32_t length; 629 }; 630 631 /** 632 * Read a flash entry from the fdt 633 * 634 * @param blob FDT blob 635 * @param node Offset of node to read 636 * @param name Name of node being read 637 * @param entry Place to put offset and size of this node 638 * @return 0 if ok, -ve on error 639 */ 640 int fdtdec_read_fmap_entry(const void *blob, int node, const char *name, 641 struct fmap_entry *entry); 642 643 /** 644 * Obtain an indexed resource from a device property. 645 * 646 * @param fdt FDT blob 647 * @param node node to examine 648 * @param property name of the property to parse 649 * @param index index of the resource to retrieve 650 * @param res returns the resource 651 * @return 0 if ok, negative on error 652 */ 653 int fdt_get_resource(const void *fdt, int node, const char *property, 654 unsigned int index, struct fdt_resource *res); 655 656 /** 657 * Obtain a named resource from a device property. 658 * 659 * Look up the index of the name in a list of strings and return the resource 660 * at that index. 661 * 662 * @param fdt FDT blob 663 * @param node node to examine 664 * @param property name of the property to parse 665 * @param prop_names name of the property containing the list of names 666 * @param name the name of the entry to look up 667 * @param res returns the resource 668 */ 669 int fdt_get_named_resource(const void *fdt, int node, const char *property, 670 const char *prop_names, const char *name, 671 struct fdt_resource *res); 672 673 /** 674 * Look at the reg property of a device node that represents a PCI device 675 * and parse the bus, device and function number from it. 676 * 677 * @param fdt FDT blob 678 * @param node node to examine 679 * @param bdf returns bus, device, function triplet 680 * @return 0 if ok, negative on error 681 */ 682 int fdtdec_pci_get_bdf(const void *fdt, int node, int *bdf); 683 684 #endif 685