fdtdec.h 26 KB

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  1. /*
  2. * Copyright (c) 2011 The Chromium OS Authors.
  3. * SPDX-License-Identifier: GPL-2.0+
  4. */
  5. #ifndef __fdtdec_h
  6. #define __fdtdec_h
  7. /*
  8. * This file contains convenience functions for decoding useful and
  9. * enlightening information from FDTs. It is intended to be used by device
  10. * drivers and board-specific code within U-Boot. It aims to reduce the
  11. * amount of FDT munging required within U-Boot itself, so that driver code
  12. * changes to support FDT are minimized.
  13. */
  14. #include <libfdt.h>
  15. /*
  16. * A typedef for a physical address. Note that fdt data is always big
  17. * endian even on a litle endian machine.
  18. */
  19. #ifdef CONFIG_PHYS_64BIT
  20. typedef u64 fdt_addr_t;
  21. typedef u64 fdt_size_t;
  22. #define FDT_ADDR_T_NONE (-1ULL)
  23. #define fdt_addr_to_cpu(reg) be64_to_cpu(reg)
  24. #define fdt_size_to_cpu(reg) be64_to_cpu(reg)
  25. #else
  26. typedef u32 fdt_addr_t;
  27. typedef u32 fdt_size_t;
  28. #define FDT_ADDR_T_NONE (-1U)
  29. #define fdt_addr_to_cpu(reg) be32_to_cpu(reg)
  30. #define fdt_size_to_cpu(reg) be32_to_cpu(reg)
  31. #endif
  32. /* Information obtained about memory from the FDT */
  33. struct fdt_memory {
  34. fdt_addr_t start;
  35. fdt_addr_t end;
  36. };
  37. /*
  38. * Information about a resource. start is the first address of the resource
  39. * and end is the last address (inclusive). The length of the resource will
  40. * be equal to: end - start + 1.
  41. */
  42. struct fdt_resource {
  43. fdt_addr_t start;
  44. fdt_addr_t end;
  45. };
  46. /**
  47. * Compute the size of a resource.
  48. *
  49. * @param res the resource to operate on
  50. * @return the size of the resource
  51. */
  52. static inline fdt_size_t fdt_resource_size(const struct fdt_resource *res)
  53. {
  54. return res->end - res->start + 1;
  55. }
  56. /**
  57. * Compat types that we know about and for which we might have drivers.
  58. * Each is named COMPAT_<dir>_<filename> where <dir> is the directory
  59. * within drivers.
  60. */
  61. enum fdt_compat_id {
  62. COMPAT_UNKNOWN,
  63. COMPAT_NVIDIA_TEGRA20_USB, /* Tegra20 USB port */
  64. COMPAT_NVIDIA_TEGRA30_USB, /* Tegra30 USB port */
  65. COMPAT_NVIDIA_TEGRA114_USB, /* Tegra114 USB port */
  66. COMPAT_NVIDIA_TEGRA114_I2C, /* Tegra114 I2C w/single clock source */
  67. COMPAT_NVIDIA_TEGRA20_I2C, /* Tegra20 i2c */
  68. COMPAT_NVIDIA_TEGRA20_DVC, /* Tegra20 dvc (really just i2c) */
  69. COMPAT_NVIDIA_TEGRA20_EMC, /* Tegra20 memory controller */
  70. COMPAT_NVIDIA_TEGRA20_EMC_TABLE, /* Tegra20 memory timing table */
  71. COMPAT_NVIDIA_TEGRA20_KBC, /* Tegra20 Keyboard */
  72. COMPAT_NVIDIA_TEGRA20_NAND, /* Tegra2 NAND controller */
  73. COMPAT_NVIDIA_TEGRA20_PWM, /* Tegra 2 PWM controller */
  74. COMPAT_NVIDIA_TEGRA20_DC, /* Tegra 2 Display controller */
  75. COMPAT_NVIDIA_TEGRA124_SDMMC, /* Tegra124 SDMMC controller */
  76. COMPAT_NVIDIA_TEGRA30_SDMMC, /* Tegra30 SDMMC controller */
  77. COMPAT_NVIDIA_TEGRA20_SDMMC, /* Tegra20 SDMMC controller */
  78. COMPAT_NVIDIA_TEGRA20_SFLASH, /* Tegra 2 SPI flash controller */
  79. COMPAT_NVIDIA_TEGRA20_SLINK, /* Tegra 2 SPI SLINK controller */
  80. COMPAT_NVIDIA_TEGRA114_SPI, /* Tegra 114 SPI controller */
  81. COMPAT_NVIDIA_TEGRA124_XUSB_PADCTL,
  82. /* Tegra124 XUSB pad controller */
  83. COMPAT_SMSC_LAN9215, /* SMSC 10/100 Ethernet LAN9215 */
  84. COMPAT_SAMSUNG_EXYNOS5_SROMC, /* Exynos5 SROMC */
  85. COMPAT_SAMSUNG_S3C2440_I2C, /* Exynos I2C Controller */
  86. COMPAT_SAMSUNG_EXYNOS5_SOUND, /* Exynos Sound */
  87. COMPAT_WOLFSON_WM8994_CODEC, /* Wolfson WM8994 Sound Codec */
  88. COMPAT_SAMSUNG_EXYNOS_SPI, /* Exynos SPI */
  89. COMPAT_GOOGLE_CROS_EC, /* Google CROS_EC Protocol */
  90. COMPAT_GOOGLE_CROS_EC_KEYB, /* Google CROS_EC Keyboard */
  91. COMPAT_SAMSUNG_EXYNOS_EHCI, /* Exynos EHCI controller */
  92. COMPAT_SAMSUNG_EXYNOS5_XHCI, /* Exynos5 XHCI controller */
  93. COMPAT_SAMSUNG_EXYNOS_USB_PHY, /* Exynos phy controller for usb2.0 */
  94. COMPAT_SAMSUNG_EXYNOS5_USB3_PHY,/* Exynos phy controller for usb3.0 */
  95. COMPAT_SAMSUNG_EXYNOS_TMU, /* Exynos TMU */
  96. COMPAT_SAMSUNG_EXYNOS_FIMD, /* Exynos Display controller */
  97. COMPAT_SAMSUNG_EXYNOS_MIPI_DSI, /* Exynos mipi dsi */
  98. COMPAT_SAMSUNG_EXYNOS5_DP, /* Exynos Display port controller */
  99. COMPAT_SAMSUNG_EXYNOS_DWMMC, /* Exynos DWMMC controller */
  100. COMPAT_SAMSUNG_EXYNOS_MMC, /* Exynos MMC controller */
  101. COMPAT_SAMSUNG_EXYNOS_SERIAL, /* Exynos UART */
  102. COMPAT_MAXIM_MAX77686_PMIC, /* MAX77686 PMIC */
  103. COMPAT_GENERIC_SPI_FLASH, /* Generic SPI Flash chip */
  104. COMPAT_MAXIM_98095_CODEC, /* MAX98095 Codec */
  105. COMPAT_INFINEON_SLB9635_TPM, /* Infineon SLB9635 TPM */
  106. COMPAT_INFINEON_SLB9645_TPM, /* Infineon SLB9645 TPM */
  107. COMPAT_SAMSUNG_EXYNOS5_I2C, /* Exynos5 High Speed I2C Controller */
  108. COMPAT_SANDBOX_HOST_EMULATION, /* Sandbox emulation of a function */
  109. COMPAT_SANDBOX_LCD_SDL, /* Sandbox LCD emulation with SDL */
  110. COMPAT_TI_TPS65090, /* Texas Instrument TPS65090 */
  111. COMPAT_NXP_PTN3460, /* NXP PTN3460 DP/LVDS bridge */
  112. COMPAT_SAMSUNG_EXYNOS_SYSMMU, /* Exynos sysmmu */
  113. COMPAT_PARADE_PS8625, /* Parade PS8622 EDP->LVDS bridge */
  114. COMPAT_INTEL_LPC, /* Intel Low Pin Count I/F */
  115. COMPAT_INTEL_MICROCODE, /* Intel microcode update */
  116. COMPAT_MEMORY_SPD, /* Memory SPD information */
  117. COMPAT_INTEL_PANTHERPOINT_AHCI, /* Intel Pantherpoint AHCI */
  118. COMPAT_INTEL_MODEL_206AX, /* Intel Model 206AX CPU */
  119. COMPAT_INTEL_GMA, /* Intel Graphics Media Accelerator */
  120. COMPAT_AMS_AS3722, /* AMS AS3722 PMIC */
  121. COMPAT_COUNT,
  122. };
  123. /* GPIOs are numbered from 0 */
  124. enum {
  125. FDT_GPIO_NONE = -1U, /* an invalid GPIO used to end our list */
  126. FDT_GPIO_ACTIVE_LOW = 1 << 0, /* input is active low (else high) */
  127. };
  128. /* This is the state of a GPIO pin as defined by the fdt */
  129. struct fdt_gpio_state {
  130. const char *name; /* name of the fdt property defining this */
  131. uint gpio; /* GPIO number, or FDT_GPIO_NONE if none */
  132. u8 flags; /* FDT_GPIO_... flags */
  133. };
  134. /* This tells us whether a fdt_gpio_state record is valid or not */
  135. #define fdt_gpio_isvalid(x) ((x)->gpio != FDT_GPIO_NONE)
  136. /**
  137. * Read the GPIO taking into account the polarity of the pin.
  138. *
  139. * @param gpio pointer to the decoded gpio
  140. * @return value of the gpio if successful, < 0 if unsuccessful
  141. */
  142. int fdtdec_get_gpio(struct fdt_gpio_state *gpio);
  143. /**
  144. * Write the GPIO taking into account the polarity of the pin.
  145. *
  146. * @param gpio pointer to the decoded gpio
  147. * @return 0 if successful
  148. */
  149. int fdtdec_set_gpio(struct fdt_gpio_state *gpio, int val);
  150. /**
  151. * Find the next numbered alias for a peripheral. This is used to enumerate
  152. * all the peripherals of a certain type.
  153. *
  154. * Do the first call with *upto = 0. Assuming /aliases/<name>0 exists then
  155. * this function will return a pointer to the node the alias points to, and
  156. * then update *upto to 1. Next time you call this function, the next node
  157. * will be returned.
  158. *
  159. * All nodes returned will match the compatible ID, as it is assumed that
  160. * all peripherals use the same driver.
  161. *
  162. * @param blob FDT blob to use
  163. * @param name Root name of alias to search for
  164. * @param id Compatible ID to look for
  165. * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
  166. */
  167. int fdtdec_next_alias(const void *blob, const char *name,
  168. enum fdt_compat_id id, int *upto);
  169. /**
  170. * Find the compatible ID for a given node.
  171. *
  172. * Generally each node has at least one compatible string attached to it.
  173. * This function looks through our list of known compatible strings and
  174. * returns the corresponding ID which matches the compatible string.
  175. *
  176. * @param blob FDT blob to use
  177. * @param node Node containing compatible string to find
  178. * @return compatible ID, or COMPAT_UNKNOWN if we cannot find a match
  179. */
  180. enum fdt_compat_id fdtdec_lookup(const void *blob, int node);
  181. /**
  182. * Find the next compatible node for a peripheral.
  183. *
  184. * Do the first call with node = 0. This function will return a pointer to
  185. * the next compatible node. Next time you call this function, pass the
  186. * value returned, and the next node will be provided.
  187. *
  188. * @param blob FDT blob to use
  189. * @param node Start node for search
  190. * @param id Compatible ID to look for (enum fdt_compat_id)
  191. * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
  192. */
  193. int fdtdec_next_compatible(const void *blob, int node,
  194. enum fdt_compat_id id);
  195. /**
  196. * Find the next compatible subnode for a peripheral.
  197. *
  198. * Do the first call with node set to the parent and depth = 0. This
  199. * function will return the offset of the next compatible node. Next time
  200. * you call this function, pass the node value returned last time, with
  201. * depth unchanged, 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. * @param depthp Current depth (set to 0 before first call)
  207. * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
  208. */
  209. int fdtdec_next_compatible_subnode(const void *blob, int node,
  210. enum fdt_compat_id id, int *depthp);
  211. /**
  212. * Look up an address property in a node and return it as an address.
  213. * The property must hold either one address with no trailing data or
  214. * one address with a length. This is only tested on 32-bit machines.
  215. *
  216. * @param blob FDT blob
  217. * @param node node to examine
  218. * @param prop_name name of property to find
  219. * @return address, if found, or FDT_ADDR_T_NONE if not
  220. */
  221. fdt_addr_t fdtdec_get_addr(const void *blob, int node,
  222. const char *prop_name);
  223. /**
  224. * Look up an address property in a node and return it as an address.
  225. * The property must hold one address with a length. This is only tested
  226. * on 32-bit machines.
  227. *
  228. * @param blob FDT blob
  229. * @param node node to examine
  230. * @param prop_name name of property to find
  231. * @return address, if found, or FDT_ADDR_T_NONE if not
  232. */
  233. fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
  234. const char *prop_name, fdt_size_t *sizep);
  235. /**
  236. * Look up a 32-bit integer property in a node and return it. The property
  237. * must have at least 4 bytes of data. The value of the first cell is
  238. * returned.
  239. *
  240. * @param blob FDT blob
  241. * @param node node to examine
  242. * @param prop_name name of property to find
  243. * @param default_val default value to return if the property is not found
  244. * @return integer value, if found, or default_val if not
  245. */
  246. s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
  247. s32 default_val);
  248. /**
  249. * Look up a 64-bit integer property in a node and return it. The property
  250. * must have at least 8 bytes of data (2 cells). The first two cells are
  251. * concatenated to form a 8 bytes value, where the first cell is top half and
  252. * the second cell is bottom half.
  253. *
  254. * @param blob FDT blob
  255. * @param node node to examine
  256. * @param prop_name name of property to find
  257. * @param default_val default value to return if the property is not found
  258. * @return integer value, if found, or default_val if not
  259. */
  260. uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
  261. uint64_t default_val);
  262. /**
  263. * Checks whether a node is enabled.
  264. * This looks for a 'status' property. If this exists, then returns 1 if
  265. * the status is 'ok' and 0 otherwise. If there is no status property,
  266. * it returns 1 on the assumption that anything mentioned should be enabled
  267. * by default.
  268. *
  269. * @param blob FDT blob
  270. * @param node node to examine
  271. * @return integer value 0 (not enabled) or 1 (enabled)
  272. */
  273. int fdtdec_get_is_enabled(const void *blob, int node);
  274. /**
  275. * Make sure we have a valid fdt available to control U-Boot.
  276. *
  277. * If not, a message is printed to the console if the console is ready.
  278. *
  279. * @return 0 if all ok, -1 if not
  280. */
  281. int fdtdec_prepare_fdt(void);
  282. /**
  283. * Checks that we have a valid fdt available to control U-Boot.
  284. * However, if not then for the moment nothing is done, since this function
  285. * is called too early to panic().
  286. *
  287. * @returns 0
  288. */
  289. int fdtdec_check_fdt(void);
  290. /**
  291. * Find the nodes for a peripheral and return a list of them in the correct
  292. * order. This is used to enumerate all the peripherals of a certain type.
  293. *
  294. * To use this, optionally set up a /aliases node with alias properties for
  295. * a peripheral. For example, for usb you could have:
  296. *
  297. * aliases {
  298. * usb0 = "/ehci@c5008000";
  299. * usb1 = "/ehci@c5000000";
  300. * };
  301. *
  302. * Pass "usb" as the name to this function and will return a list of two
  303. * nodes offsets: /ehci@c5008000 and ehci@c5000000.
  304. *
  305. * All nodes returned will match the compatible ID, as it is assumed that
  306. * all peripherals use the same driver.
  307. *
  308. * If no alias node is found, then the node list will be returned in the
  309. * order found in the fdt. If the aliases mention a node which doesn't
  310. * exist, then this will be ignored. If nodes are found with no aliases,
  311. * they will be added in any order.
  312. *
  313. * If there is a gap in the aliases, then this function return a 0 node at
  314. * that position. The return value will also count these gaps.
  315. *
  316. * This function checks node properties and will not return nodes which are
  317. * marked disabled (status = "disabled").
  318. *
  319. * @param blob FDT blob to use
  320. * @param name Root name of alias to search for
  321. * @param id Compatible ID to look for
  322. * @param node_list Place to put list of found nodes
  323. * @param maxcount Maximum number of nodes to find
  324. * @return number of nodes found on success, FTD_ERR_... on error
  325. */
  326. int fdtdec_find_aliases_for_id(const void *blob, const char *name,
  327. enum fdt_compat_id id, int *node_list, int maxcount);
  328. /*
  329. * This function is similar to fdtdec_find_aliases_for_id() except that it
  330. * adds to the node_list that is passed in. Any 0 elements are considered
  331. * available for allocation - others are considered already used and are
  332. * skipped.
  333. *
  334. * You can use this by calling fdtdec_find_aliases_for_id() with an
  335. * uninitialised array, then setting the elements that are returned to -1,
  336. * say, then calling this function, perhaps with a different compat id.
  337. * Any elements you get back that are >0 are new nodes added by the call
  338. * to this function.
  339. *
  340. * Note that if you have some nodes with aliases and some without, you are
  341. * sailing close to the wind. The call to fdtdec_find_aliases_for_id() with
  342. * one compat_id may fill in positions for which you have aliases defined
  343. * for another compat_id. When you later call *this* function with the second
  344. * compat_id, the alias positions may already be used. A debug warning may
  345. * be generated in this case, but it is safest to define aliases for all
  346. * nodes when you care about the ordering.
  347. */
  348. int fdtdec_add_aliases_for_id(const void *blob, const char *name,
  349. enum fdt_compat_id id, int *node_list, int maxcount);
  350. /**
  351. * Get the alias sequence number of a node
  352. *
  353. * This works out whether a node is pointed to by an alias, and if so, the
  354. * sequence number of that alias. Aliases are of the form <base><num> where
  355. * <num> is the sequence number. For example spi2 would be sequence number
  356. * 2.
  357. *
  358. * @param blob Device tree blob (if NULL, then error is returned)
  359. * @param base Base name for alias (before the underscore)
  360. * @param node Node to look up
  361. * @param seqp This is set to the sequence number if one is found,
  362. * but otherwise the value is left alone
  363. * @return 0 if a sequence was found, -ve if not
  364. */
  365. int fdtdec_get_alias_seq(const void *blob, const char *base, int node,
  366. int *seqp);
  367. /**
  368. * Get the offset of the given chosen node
  369. *
  370. * This looks up a property in /chosen containing the path to another node,
  371. * then finds the offset of that node.
  372. *
  373. * @param blob Device tree blob (if NULL, then error is returned)
  374. * @param name Property name, e.g. "stdout-path"
  375. * @return Node offset referred to by that chosen node, or -ve FDT_ERR_...
  376. */
  377. int fdtdec_get_chosen_node(const void *blob, const char *name);
  378. /*
  379. * Get the name for a compatible ID
  380. *
  381. * @param id Compatible ID to look for
  382. * @return compatible string for that id
  383. */
  384. const char *fdtdec_get_compatible(enum fdt_compat_id id);
  385. /* Look up a phandle and follow it to its node. Then return the offset
  386. * of that node.
  387. *
  388. * @param blob FDT blob
  389. * @param node node to examine
  390. * @param prop_name name of property to find
  391. * @return node offset if found, -ve error code on error
  392. */
  393. int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name);
  394. /**
  395. * Look up a property in a node and return its contents in an integer
  396. * array of given length. The property must have at least enough data for
  397. * the array (4*count bytes). It may have more, but this will be ignored.
  398. *
  399. * @param blob FDT blob
  400. * @param node node to examine
  401. * @param prop_name name of property to find
  402. * @param array array to fill with data
  403. * @param count number of array elements
  404. * @return 0 if ok, or -FDT_ERR_NOTFOUND if the property is not found,
  405. * or -FDT_ERR_BADLAYOUT if not enough data
  406. */
  407. int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
  408. u32 *array, int count);
  409. /**
  410. * Look up a property in a node and return its contents in an integer
  411. * array of given length. The property must exist but may have less data that
  412. * expected (4*count bytes). It may have more, but this will be ignored.
  413. *
  414. * @param blob FDT blob
  415. * @param node node to examine
  416. * @param prop_name name of property to find
  417. * @param array array to fill with data
  418. * @param count number of array elements
  419. * @return number of array elements if ok, or -FDT_ERR_NOTFOUND if the
  420. * property is not found
  421. */
  422. int fdtdec_get_int_array_count(const void *blob, int node,
  423. const char *prop_name, u32 *array, int count);
  424. /**
  425. * Look up a property in a node and return a pointer to its contents as a
  426. * unsigned int array of given length. The property must have at least enough
  427. * data for the array ('count' cells). It may have more, but this will be
  428. * ignored. The data is not copied.
  429. *
  430. * Note that you must access elements of the array with fdt32_to_cpu(),
  431. * since the elements will be big endian even on a little endian machine.
  432. *
  433. * @param blob FDT blob
  434. * @param node node to examine
  435. * @param prop_name name of property to find
  436. * @param count number of array elements
  437. * @return pointer to array if found, or NULL if the property is not
  438. * found or there is not enough data
  439. */
  440. const u32 *fdtdec_locate_array(const void *blob, int node,
  441. const char *prop_name, int count);
  442. /**
  443. * Look up a boolean property in a node and return it.
  444. *
  445. * A boolean properly is true if present in the device tree and false if not
  446. * present, regardless of its value.
  447. *
  448. * @param blob FDT blob
  449. * @param node node to examine
  450. * @param prop_name name of property to find
  451. * @return 1 if the properly is present; 0 if it isn't present
  452. */
  453. int fdtdec_get_bool(const void *blob, int node, const char *prop_name);
  454. /**
  455. * Decode a single GPIOs from an FDT.
  456. *
  457. * If the property is not found, then the GPIO structure will still be
  458. * initialised, with gpio set to FDT_GPIO_NONE. This makes it easy to
  459. * provide optional GPIOs.
  460. *
  461. * @param blob FDT blob to use
  462. * @param node Node to look at
  463. * @param prop_name Node property name
  464. * @param gpio gpio elements to fill from FDT
  465. * @return 0 if ok, -FDT_ERR_NOTFOUND if the property is missing.
  466. */
  467. int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name,
  468. struct fdt_gpio_state *gpio);
  469. /**
  470. * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no
  471. * terminating item.
  472. *
  473. * @param blob FDT blob to use
  474. * @param node Node to look at
  475. * @param prop_name Node property name
  476. * @param gpio Array of gpio elements to fill from FDT. This will be
  477. * untouched if either 0 or an error is returned
  478. * @param max_count Maximum number of elements allowed
  479. * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would
  480. * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing.
  481. */
  482. int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name,
  483. struct fdt_gpio_state *gpio, int max_count);
  484. /**
  485. * Set up a GPIO pin according to the provided gpio information. At present this
  486. * just requests the GPIO.
  487. *
  488. * If the gpio is FDT_GPIO_NONE, no action is taken. This makes it easy to
  489. * deal with optional GPIOs.
  490. *
  491. * @param gpio GPIO info to use for set up
  492. * @return 0 if all ok or gpio was FDT_GPIO_NONE; -1 on error
  493. */
  494. int fdtdec_setup_gpio(struct fdt_gpio_state *gpio);
  495. /**
  496. * Look in the FDT for a config item with the given name and return its value
  497. * as a 32-bit integer. The property must have at least 4 bytes of data. The
  498. * value of the first cell is returned.
  499. *
  500. * @param blob FDT blob to use
  501. * @param prop_name Node property name
  502. * @param default_val default value to return if the property is not found
  503. * @return integer value, if found, or default_val if not
  504. */
  505. int fdtdec_get_config_int(const void *blob, const char *prop_name,
  506. int default_val);
  507. /**
  508. * Look in the FDT for a config item with the given name
  509. * and return whether it exists.
  510. *
  511. * @param blob FDT blob
  512. * @param prop_name property name to look up
  513. * @return 1, if it exists, or 0 if not
  514. */
  515. int fdtdec_get_config_bool(const void *blob, const char *prop_name);
  516. /**
  517. * Look in the FDT for a config item with the given name and return its value
  518. * as a string.
  519. *
  520. * @param blob FDT blob
  521. * @param prop_name property name to look up
  522. * @returns property string, NULL on error.
  523. */
  524. char *fdtdec_get_config_string(const void *blob, const char *prop_name);
  525. /*
  526. * Look up a property in a node and return its contents in a byte
  527. * array of given length. The property must have at least enough data for
  528. * the array (count bytes). It may have more, but this will be ignored.
  529. *
  530. * @param blob FDT blob
  531. * @param node node to examine
  532. * @param prop_name name of property to find
  533. * @param array array to fill with data
  534. * @param count number of array elements
  535. * @return 0 if ok, or -FDT_ERR_MISSING if the property is not found,
  536. * or -FDT_ERR_BADLAYOUT if not enough data
  537. */
  538. int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
  539. u8 *array, int count);
  540. /**
  541. * Look up a property in a node and return a pointer to its contents as a
  542. * byte array of given length. The property must have at least enough data
  543. * for the array (count bytes). It may have more, but this will be ignored.
  544. * The data is not copied.
  545. *
  546. * @param blob FDT blob
  547. * @param node node to examine
  548. * @param prop_name name of property to find
  549. * @param count number of array elements
  550. * @return pointer to byte array if found, or NULL if the property is not
  551. * found or there is not enough data
  552. */
  553. const u8 *fdtdec_locate_byte_array(const void *blob, int node,
  554. const char *prop_name, int count);
  555. /**
  556. * Look up a property in a node which contains a memory region address and
  557. * size. Then return a pointer to this address.
  558. *
  559. * The property must hold one address with a length. This is only tested on
  560. * 32-bit machines.
  561. *
  562. * @param blob FDT blob
  563. * @param node node to examine
  564. * @param prop_name name of property to find
  565. * @param basep Returns base address of region
  566. * @param size Returns size of region
  567. * @return 0 if ok, -1 on error (property not found)
  568. */
  569. int fdtdec_decode_region(const void *blob, int node, const char *prop_name,
  570. fdt_addr_t *basep, fdt_size_t *sizep);
  571. enum fmap_compress_t {
  572. FMAP_COMPRESS_NONE,
  573. FMAP_COMPRESS_LZO,
  574. };
  575. enum fmap_hash_t {
  576. FMAP_HASH_NONE,
  577. FMAP_HASH_SHA1,
  578. FMAP_HASH_SHA256,
  579. };
  580. /* A flash map entry, containing an offset and length */
  581. struct fmap_entry {
  582. uint32_t offset;
  583. uint32_t length;
  584. uint32_t used; /* Number of bytes used in region */
  585. enum fmap_compress_t compress_algo; /* Compression type */
  586. enum fmap_hash_t hash_algo; /* Hash algorithm */
  587. const uint8_t *hash; /* Hash value */
  588. int hash_size; /* Hash size */
  589. };
  590. /**
  591. * Read a flash entry from the fdt
  592. *
  593. * @param blob FDT blob
  594. * @param node Offset of node to read
  595. * @param name Name of node being read
  596. * @param entry Place to put offset and size of this node
  597. * @return 0 if ok, -ve on error
  598. */
  599. int fdtdec_read_fmap_entry(const void *blob, int node, const char *name,
  600. struct fmap_entry *entry);
  601. /**
  602. * Obtain an indexed resource from a device property.
  603. *
  604. * @param fdt FDT blob
  605. * @param node node to examine
  606. * @param property name of the property to parse
  607. * @param index index of the resource to retrieve
  608. * @param res returns the resource
  609. * @return 0 if ok, negative on error
  610. */
  611. int fdt_get_resource(const void *fdt, int node, const char *property,
  612. unsigned int index, struct fdt_resource *res);
  613. /**
  614. * Obtain a named resource from a device property.
  615. *
  616. * Look up the index of the name in a list of strings and return the resource
  617. * at that index.
  618. *
  619. * @param fdt FDT blob
  620. * @param node node to examine
  621. * @param property name of the property to parse
  622. * @param prop_names name of the property containing the list of names
  623. * @param name the name of the entry to look up
  624. * @param res returns the resource
  625. */
  626. int fdt_get_named_resource(const void *fdt, int node, const char *property,
  627. const char *prop_names, const char *name,
  628. struct fdt_resource *res);
  629. /**
  630. * Look at the reg property of a device node that represents a PCI device
  631. * and parse the bus, device and function number from it.
  632. *
  633. * @param fdt FDT blob
  634. * @param node node to examine
  635. * @param bdf returns bus, device, function triplet
  636. * @return 0 if ok, negative on error
  637. */
  638. int fdtdec_pci_get_bdf(const void *fdt, int node, int *bdf);
  639. /**
  640. * Decode a named region within a memory bank of a given type.
  641. *
  642. * This function handles selection of a memory region. The region is
  643. * specified as an offset/size within a particular type of memory.
  644. *
  645. * The properties used are:
  646. *
  647. * <mem_type>-memory<suffix> for the name of the memory bank
  648. * <mem_type>-offset<suffix> for the offset in that bank
  649. *
  650. * The property value must have an offset and a size. The function checks
  651. * that the region is entirely within the memory bank.5
  652. *
  653. * @param blob FDT blob
  654. * @param node Node containing the properties (-1 for /config)
  655. * @param mem_type Type of memory to use, which is a name, such as
  656. * "u-boot" or "kernel".
  657. * @param suffix String to append to the memory/offset
  658. * property names
  659. * @param basep Returns base of region
  660. * @param sizep Returns size of region
  661. * @return 0 if OK, -ive on error
  662. */
  663. int fdtdec_decode_memory_region(const void *blob, int node,
  664. const char *mem_type, const char *suffix,
  665. fdt_addr_t *basep, fdt_size_t *sizep);
  666. #endif