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 COMPAT_INTEL_GMA, /* Intel Graphics Media Accelerator */ 126 127 COMPAT_COUNT, 128 }; 129 130 /* GPIOs are numbered from 0 */ 131 enum { 132 FDT_GPIO_NONE = -1U, /* an invalid GPIO used to end our list */ 133 134 FDT_GPIO_ACTIVE_LOW = 1 << 0, /* input is active low (else high) */ 135 }; 136 137 /* This is the state of a GPIO pin as defined by the fdt */ 138 struct fdt_gpio_state { 139 const char *name; /* name of the fdt property defining this */ 140 uint gpio; /* GPIO number, or FDT_GPIO_NONE if none */ 141 u8 flags; /* FDT_GPIO_... flags */ 142 }; 143 144 /* This tells us whether a fdt_gpio_state record is valid or not */ 145 #define fdt_gpio_isvalid(x) ((x)->gpio != FDT_GPIO_NONE) 146 147 /** 148 * Read the GPIO taking into account the polarity of the pin. 149 * 150 * @param gpio pointer to the decoded gpio 151 * @return value of the gpio if successful, < 0 if unsuccessful 152 */ 153 int fdtdec_get_gpio(struct fdt_gpio_state *gpio); 154 155 /** 156 * Write the GPIO taking into account the polarity of the pin. 157 * 158 * @param gpio pointer to the decoded gpio 159 * @return 0 if successful 160 */ 161 int fdtdec_set_gpio(struct fdt_gpio_state *gpio, int val); 162 163 /** 164 * Find the next numbered alias for a peripheral. This is used to enumerate 165 * all the peripherals of a certain type. 166 * 167 * Do the first call with *upto = 0. Assuming /aliases/<name>0 exists then 168 * this function will return a pointer to the node the alias points to, and 169 * then update *upto to 1. Next time you call this function, the next node 170 * will be returned. 171 * 172 * All nodes returned will match the compatible ID, as it is assumed that 173 * all peripherals use the same driver. 174 * 175 * @param blob FDT blob to use 176 * @param name Root name of alias to search for 177 * @param id Compatible ID to look for 178 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more 179 */ 180 int fdtdec_next_alias(const void *blob, const char *name, 181 enum fdt_compat_id id, int *upto); 182 183 /** 184 * Find the compatible ID for a given node. 185 * 186 * Generally each node has at least one compatible string attached to it. 187 * This function looks through our list of known compatible strings and 188 * returns the corresponding ID which matches the compatible string. 189 * 190 * @param blob FDT blob to use 191 * @param node Node containing compatible string to find 192 * @return compatible ID, or COMPAT_UNKNOWN if we cannot find a match 193 */ 194 enum fdt_compat_id fdtdec_lookup(const void *blob, int node); 195 196 /** 197 * Find the next compatible node for a peripheral. 198 * 199 * Do the first call with node = 0. This function will return a pointer to 200 * the next compatible node. Next time you call this function, pass the 201 * value returned, and the next node will be provided. 202 * 203 * @param blob FDT blob to use 204 * @param node Start node for search 205 * @param id Compatible ID to look for (enum fdt_compat_id) 206 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more 207 */ 208 int fdtdec_next_compatible(const void *blob, int node, 209 enum fdt_compat_id id); 210 211 /** 212 * Find the next compatible subnode for a peripheral. 213 * 214 * Do the first call with node set to the parent and depth = 0. This 215 * function will return the offset of the next compatible node. Next time 216 * you call this function, pass the node value returned last time, with 217 * depth unchanged, and the next node will be provided. 218 * 219 * @param blob FDT blob to use 220 * @param node Start node for search 221 * @param id Compatible ID to look for (enum fdt_compat_id) 222 * @param depthp Current depth (set to 0 before first call) 223 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more 224 */ 225 int fdtdec_next_compatible_subnode(const void *blob, int node, 226 enum fdt_compat_id id, int *depthp); 227 228 /** 229 * Look up an address property in a node and return it as an address. 230 * The property must hold either one address with no trailing data or 231 * one address with a length. This is only tested on 32-bit machines. 232 * 233 * @param blob FDT blob 234 * @param node node to examine 235 * @param prop_name name of property to find 236 * @return address, if found, or FDT_ADDR_T_NONE if not 237 */ 238 fdt_addr_t fdtdec_get_addr(const void *blob, int node, 239 const char *prop_name); 240 241 /** 242 * Look up an address property in a node and return it as an address. 243 * The property must hold one address with a length. This is only tested 244 * on 32-bit machines. 245 * 246 * @param blob FDT blob 247 * @param node node to examine 248 * @param prop_name name of property to find 249 * @return address, if found, or FDT_ADDR_T_NONE if not 250 */ 251 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node, 252 const char *prop_name, fdt_size_t *sizep); 253 254 /** 255 * Look up a 32-bit integer property in a node and return it. The property 256 * must have at least 4 bytes of data. The value of the first cell is 257 * returned. 258 * 259 * @param blob FDT blob 260 * @param node node to examine 261 * @param prop_name name of property to find 262 * @param default_val default value to return if the property is not found 263 * @return integer value, if found, or default_val if not 264 */ 265 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name, 266 s32 default_val); 267 268 /** 269 * Look up a 64-bit integer property in a node and return it. The property 270 * must have at least 8 bytes of data (2 cells). The first two cells are 271 * concatenated to form a 8 bytes value, where the first cell is top half and 272 * the second cell is bottom half. 273 * 274 * @param blob FDT blob 275 * @param node node to examine 276 * @param prop_name name of property to find 277 * @param default_val default value to return if the property is not found 278 * @return integer value, if found, or default_val if not 279 */ 280 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name, 281 uint64_t default_val); 282 283 /** 284 * Checks whether a node is enabled. 285 * This looks for a 'status' property. If this exists, then returns 1 if 286 * the status is 'ok' and 0 otherwise. If there is no status property, 287 * it returns 1 on the assumption that anything mentioned should be enabled 288 * by default. 289 * 290 * @param blob FDT blob 291 * @param node node to examine 292 * @return integer value 0 (not enabled) or 1 (enabled) 293 */ 294 int fdtdec_get_is_enabled(const void *blob, int node); 295 296 /** 297 * Make sure we have a valid fdt available to control U-Boot. 298 * 299 * If not, a message is printed to the console if the console is ready. 300 * 301 * @return 0 if all ok, -1 if not 302 */ 303 int fdtdec_prepare_fdt(void); 304 305 /** 306 * Checks that we have a valid fdt available to control U-Boot. 307 308 * However, if not then for the moment nothing is done, since this function 309 * is called too early to panic(). 310 * 311 * @returns 0 312 */ 313 int fdtdec_check_fdt(void); 314 315 /** 316 * Find the nodes for a peripheral and return a list of them in the correct 317 * order. This is used to enumerate all the peripherals of a certain type. 318 * 319 * To use this, optionally set up a /aliases node with alias properties for 320 * a peripheral. For example, for usb you could have: 321 * 322 * aliases { 323 * usb0 = "/ehci@c5008000"; 324 * usb1 = "/ehci@c5000000"; 325 * }; 326 * 327 * Pass "usb" as the name to this function and will return a list of two 328 * nodes offsets: /ehci@c5008000 and ehci@c5000000. 329 * 330 * All nodes returned will match the compatible ID, as it is assumed that 331 * all peripherals use the same driver. 332 * 333 * If no alias node is found, then the node list will be returned in the 334 * order found in the fdt. If the aliases mention a node which doesn't 335 * exist, then this will be ignored. If nodes are found with no aliases, 336 * they will be added in any order. 337 * 338 * If there is a gap in the aliases, then this function return a 0 node at 339 * that position. The return value will also count these gaps. 340 * 341 * This function checks node properties and will not return nodes which are 342 * marked disabled (status = "disabled"). 343 * 344 * @param blob FDT blob to use 345 * @param name Root name of alias to search for 346 * @param id Compatible ID to look for 347 * @param node_list Place to put list of found nodes 348 * @param maxcount Maximum number of nodes to find 349 * @return number of nodes found on success, FTD_ERR_... on error 350 */ 351 int fdtdec_find_aliases_for_id(const void *blob, const char *name, 352 enum fdt_compat_id id, int *node_list, int maxcount); 353 354 /* 355 * This function is similar to fdtdec_find_aliases_for_id() except that it 356 * adds to the node_list that is passed in. Any 0 elements are considered 357 * available for allocation - others are considered already used and are 358 * skipped. 359 * 360 * You can use this by calling fdtdec_find_aliases_for_id() with an 361 * uninitialised array, then setting the elements that are returned to -1, 362 * say, then calling this function, perhaps with a different compat id. 363 * Any elements you get back that are >0 are new nodes added by the call 364 * to this function. 365 * 366 * Note that if you have some nodes with aliases and some without, you are 367 * sailing close to the wind. The call to fdtdec_find_aliases_for_id() with 368 * one compat_id may fill in positions for which you have aliases defined 369 * for another compat_id. When you later call *this* function with the second 370 * compat_id, the alias positions may already be used. A debug warning may 371 * be generated in this case, but it is safest to define aliases for all 372 * nodes when you care about the ordering. 373 */ 374 int fdtdec_add_aliases_for_id(const void *blob, const char *name, 375 enum fdt_compat_id id, int *node_list, int maxcount); 376 377 /** 378 * Get the alias sequence number of a node 379 * 380 * This works out whether a node is pointed to by an alias, and if so, the 381 * sequence number of that alias. Aliases are of the form <base><num> where 382 * <num> is the sequence number. For example spi2 would be sequence number 383 * 2. 384 * 385 * @param blob Device tree blob (if NULL, then error is returned) 386 * @param base Base name for alias (before the underscore) 387 * @param node Node to look up 388 * @param seqp This is set to the sequence number if one is found, 389 * but otherwise the value is left alone 390 * @return 0 if a sequence was found, -ve if not 391 */ 392 int fdtdec_get_alias_seq(const void *blob, const char *base, int node, 393 int *seqp); 394 395 /** 396 * Get the offset of the given alias node 397 * 398 * This looks up an alias in /aliases then finds the offset of that node. 399 * 400 * @param blob Device tree blob (if NULL, then error is returned) 401 * @param name Alias name, e.g. "console" 402 * @return Node offset referred to by that alias, or -ve FDT_ERR_... 403 */ 404 int fdtdec_get_alias_node(const void *blob, const char *name); 405 406 /** 407 * Get the offset of the given chosen node 408 * 409 * This looks up a property in /chosen containing the path to another node, 410 * then finds the offset of that node. 411 * 412 * @param blob Device tree blob (if NULL, then error is returned) 413 * @param name Property name, e.g. "stdout-path" 414 * @return Node offset referred to by that chosen node, or -ve FDT_ERR_... 415 */ 416 int fdtdec_get_chosen_node(const void *blob, const char *name); 417 418 /* 419 * Get the name for a compatible ID 420 * 421 * @param id Compatible ID to look for 422 * @return compatible string for that id 423 */ 424 const char *fdtdec_get_compatible(enum fdt_compat_id id); 425 426 /* Look up a phandle and follow it to its node. Then return the offset 427 * of that node. 428 * 429 * @param blob FDT blob 430 * @param node node to examine 431 * @param prop_name name of property to find 432 * @return node offset if found, -ve error code on error 433 */ 434 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name); 435 436 /** 437 * Look up a property in a node and return its contents in an integer 438 * array of given length. The property must have at least enough data for 439 * the array (4*count bytes). It may have more, but this will be ignored. 440 * 441 * @param blob FDT blob 442 * @param node node to examine 443 * @param prop_name name of property to find 444 * @param array array to fill with data 445 * @param count number of array elements 446 * @return 0 if ok, or -FDT_ERR_NOTFOUND if the property is not found, 447 * or -FDT_ERR_BADLAYOUT if not enough data 448 */ 449 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name, 450 u32 *array, int count); 451 452 /** 453 * Look up a property in a node and return its contents in an integer 454 * array of given length. The property must exist but may have less data that 455 * expected (4*count bytes). It may have more, but this will be ignored. 456 * 457 * @param blob FDT blob 458 * @param node node to examine 459 * @param prop_name name of property to find 460 * @param array array to fill with data 461 * @param count number of array elements 462 * @return number of array elements if ok, or -FDT_ERR_NOTFOUND if the 463 * property is not found 464 */ 465 int fdtdec_get_int_array_count(const void *blob, int node, 466 const char *prop_name, u32 *array, int count); 467 468 /** 469 * Look up a property in a node and return a pointer to its contents as a 470 * unsigned int array of given length. The property must have at least enough 471 * data for the array ('count' cells). It may have more, but this will be 472 * ignored. The data is not copied. 473 * 474 * Note that you must access elements of the array with fdt32_to_cpu(), 475 * since the elements will be big endian even on a little endian machine. 476 * 477 * @param blob FDT blob 478 * @param node node to examine 479 * @param prop_name name of property to find 480 * @param count number of array elements 481 * @return pointer to array if found, or NULL if the property is not 482 * found or there is not enough data 483 */ 484 const u32 *fdtdec_locate_array(const void *blob, int node, 485 const char *prop_name, int count); 486 487 /** 488 * Look up a boolean property in a node and return it. 489 * 490 * A boolean properly is true if present in the device tree and false if not 491 * present, regardless of its value. 492 * 493 * @param blob FDT blob 494 * @param node node to examine 495 * @param prop_name name of property to find 496 * @return 1 if the properly is present; 0 if it isn't present 497 */ 498 int fdtdec_get_bool(const void *blob, int node, const char *prop_name); 499 500 /** 501 * Decode a single GPIOs from an FDT. 502 * 503 * If the property is not found, then the GPIO structure will still be 504 * initialised, with gpio set to FDT_GPIO_NONE. This makes it easy to 505 * provide optional GPIOs. 506 * 507 * @param blob FDT blob to use 508 * @param node Node to look at 509 * @param prop_name Node property name 510 * @param gpio gpio elements to fill from FDT 511 * @return 0 if ok, -FDT_ERR_NOTFOUND if the property is missing. 512 */ 513 int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name, 514 struct fdt_gpio_state *gpio); 515 516 /** 517 * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no 518 * terminating item. 519 * 520 * @param blob FDT blob to use 521 * @param node Node to look at 522 * @param prop_name Node property name 523 * @param gpio Array of gpio elements to fill from FDT. This will be 524 * untouched if either 0 or an error is returned 525 * @param max_count Maximum number of elements allowed 526 * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would 527 * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing. 528 */ 529 int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name, 530 struct fdt_gpio_state *gpio, int max_count); 531 532 /** 533 * Set up a GPIO pin according to the provided gpio information. At present this 534 * just requests the GPIO. 535 * 536 * If the gpio is FDT_GPIO_NONE, no action is taken. This makes it easy to 537 * deal with optional GPIOs. 538 * 539 * @param gpio GPIO info to use for set up 540 * @return 0 if all ok or gpio was FDT_GPIO_NONE; -1 on error 541 */ 542 int fdtdec_setup_gpio(struct fdt_gpio_state *gpio); 543 544 /** 545 * Look in the FDT for a config item with the given name and return its value 546 * as a 32-bit integer. The property must have at least 4 bytes of data. The 547 * value of the first cell is returned. 548 * 549 * @param blob FDT blob to use 550 * @param prop_name Node property name 551 * @param default_val default value to return if the property is not found 552 * @return integer value, if found, or default_val if not 553 */ 554 int fdtdec_get_config_int(const void *blob, const char *prop_name, 555 int default_val); 556 557 /** 558 * Look in the FDT for a config item with the given name 559 * and return whether it exists. 560 * 561 * @param blob FDT blob 562 * @param prop_name property name to look up 563 * @return 1, if it exists, or 0 if not 564 */ 565 int fdtdec_get_config_bool(const void *blob, const char *prop_name); 566 567 /** 568 * Look in the FDT for a config item with the given name and return its value 569 * as a string. 570 * 571 * @param blob FDT blob 572 * @param prop_name property name to look up 573 * @returns property string, NULL on error. 574 */ 575 char *fdtdec_get_config_string(const void *blob, const char *prop_name); 576 577 /* 578 * Look up a property in a node and return its contents in a byte 579 * array of given length. The property must have at least enough data for 580 * the array (count bytes). It may have more, but this will be ignored. 581 * 582 * @param blob FDT blob 583 * @param node node to examine 584 * @param prop_name name of property to find 585 * @param array array to fill with data 586 * @param count number of array elements 587 * @return 0 if ok, or -FDT_ERR_MISSING if the property is not found, 588 * or -FDT_ERR_BADLAYOUT if not enough data 589 */ 590 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name, 591 u8 *array, int count); 592 593 /** 594 * Look up a property in a node and return a pointer to its contents as a 595 * byte array of given length. The property must have at least enough data 596 * for the array (count bytes). It may have more, but this will be ignored. 597 * The data is not copied. 598 * 599 * @param blob FDT blob 600 * @param node node to examine 601 * @param prop_name name of property to find 602 * @param count number of array elements 603 * @return pointer to byte array if found, or NULL if the property is not 604 * found or there is not enough data 605 */ 606 const u8 *fdtdec_locate_byte_array(const void *blob, int node, 607 const char *prop_name, int count); 608 609 /** 610 * Look up a property in a node which contains a memory region address and 611 * size. Then return a pointer to this address. 612 * 613 * The property must hold one address with a length. This is only tested on 614 * 32-bit machines. 615 * 616 * @param blob FDT blob 617 * @param node node to examine 618 * @param prop_name name of property to find 619 * @param ptrp returns pointer to region, or NULL if no address 620 * @param size returns size of region 621 * @return 0 if ok, -1 on error (propery not found) 622 */ 623 int fdtdec_decode_region(const void *blob, int node, 624 const char *prop_name, void **ptrp, size_t *size); 625 626 /* A flash map entry, containing an offset and length */ 627 struct fmap_entry { 628 uint32_t offset; 629 uint32_t length; 630 }; 631 632 /** 633 * Read a flash entry from the fdt 634 * 635 * @param blob FDT blob 636 * @param node Offset of node to read 637 * @param name Name of node being read 638 * @param entry Place to put offset and size of this node 639 * @return 0 if ok, -ve on error 640 */ 641 int fdtdec_read_fmap_entry(const void *blob, int node, const char *name, 642 struct fmap_entry *entry); 643 644 /** 645 * Obtain an indexed resource from a device property. 646 * 647 * @param fdt FDT blob 648 * @param node node to examine 649 * @param property name of the property to parse 650 * @param index index of the resource to retrieve 651 * @param res returns the resource 652 * @return 0 if ok, negative on error 653 */ 654 int fdt_get_resource(const void *fdt, int node, const char *property, 655 unsigned int index, struct fdt_resource *res); 656 657 /** 658 * Obtain a named resource from a device property. 659 * 660 * Look up the index of the name in a list of strings and return the resource 661 * at that index. 662 * 663 * @param fdt FDT blob 664 * @param node node to examine 665 * @param property name of the property to parse 666 * @param prop_names name of the property containing the list of names 667 * @param name the name of the entry to look up 668 * @param res returns the resource 669 */ 670 int fdt_get_named_resource(const void *fdt, int node, const char *property, 671 const char *prop_names, const char *name, 672 struct fdt_resource *res); 673 674 /** 675 * Look at the reg property of a device node that represents a PCI device 676 * and parse the bus, device and function number from it. 677 * 678 * @param fdt FDT blob 679 * @param node node to examine 680 * @param bdf returns bus, device, function triplet 681 * @return 0 if ok, negative on error 682 */ 683 int fdtdec_pci_get_bdf(const void *fdt, int node, int *bdf); 684 685 #endif 686