2 * Copyright (c) 2011 The Chromium OS Authors.
3 * SPDX-License-Identifier: GPL-2.0+
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.
21 * A typedef for a physical address. Note that fdt data is always big
22 * endian even on a litle endian machine.
24 #ifdef CONFIG_PHYS_64BIT
25 typedef u64 fdt_addr_t;
26 typedef u64 fdt_size_t;
27 #define FDT_ADDR_T_NONE (-1ULL)
28 #define fdt_addr_to_cpu(reg) be64_to_cpu(reg)
29 #define fdt_size_to_cpu(reg) be64_to_cpu(reg)
31 typedef u32 fdt_addr_t;
32 typedef u32 fdt_size_t;
33 #define FDT_ADDR_T_NONE (-1U)
34 #define fdt_addr_to_cpu(reg) be32_to_cpu(reg)
35 #define fdt_size_to_cpu(reg) be32_to_cpu(reg)
38 /* Information obtained about memory from the FDT */
45 * Information about a resource. start is the first address of the resource
46 * and end is the last address (inclusive). The length of the resource will
47 * be equal to: end - start + 1.
55 FDT_PCI_SPACE_CONFIG = 0,
56 FDT_PCI_SPACE_IO = 0x01000000,
57 FDT_PCI_SPACE_MEM32 = 0x02000000,
58 FDT_PCI_SPACE_MEM64 = 0x03000000,
59 FDT_PCI_SPACE_MEM32_PREF = 0x42000000,
60 FDT_PCI_SPACE_MEM64_PREF = 0x43000000,
63 #define FDT_PCI_ADDR_CELLS 3
64 #define FDT_PCI_SIZE_CELLS 2
65 #define FDT_PCI_REG_SIZE \
66 ((FDT_PCI_ADDR_CELLS + FDT_PCI_SIZE_CELLS) * sizeof(u32))
69 * The Open Firmware spec defines PCI physical address as follows:
71 * bits# 31 .... 24 23 .... 16 15 .... 08 07 .... 00
73 * phys.hi cell: npt000ss bbbbbbbb dddddfff rrrrrrrr
74 * phys.mid cell: hhhhhhhh hhhhhhhh hhhhhhhh hhhhhhhh
75 * phys.lo cell: llllllll llllllll llllllll llllllll
79 * n: is 0 if the address is relocatable, 1 otherwise
80 * p: is 1 if addressable region is prefetchable, 0 otherwise
81 * t: is 1 if the address is aliased (for non-relocatable I/O) below 1MB
82 * (for Memory), or below 64KB (for relocatable I/O)
83 * ss: is the space code, denoting the address space
84 * bbbbbbbb: is the 8-bit Bus Number
85 * ddddd: is the 5-bit Device Number
86 * fff: is the 3-bit Function Number
87 * rrrrrrrr: is the 8-bit Register Number
88 * hhhhhhhh: is a 32-bit unsigned number
89 * llllllll: is a 32-bit unsigned number
98 * Compute the size of a resource.
100 * @param res the resource to operate on
101 * @return the size of the resource
103 static inline fdt_size_t fdt_resource_size(const struct fdt_resource *res)
105 return res->end - res->start + 1;
109 * Compat types that we know about and for which we might have drivers.
110 * Each is named COMPAT_<dir>_<filename> where <dir> is the directory
115 COMPAT_NVIDIA_TEGRA20_USB, /* Tegra20 USB port */
116 COMPAT_NVIDIA_TEGRA30_USB, /* Tegra30 USB port */
117 COMPAT_NVIDIA_TEGRA114_USB, /* Tegra114 USB port */
118 COMPAT_NVIDIA_TEGRA114_I2C, /* Tegra114 I2C w/single clock source */
119 COMPAT_NVIDIA_TEGRA20_I2C, /* Tegra20 i2c */
120 COMPAT_NVIDIA_TEGRA20_DVC, /* Tegra20 dvc (really just i2c) */
121 COMPAT_NVIDIA_TEGRA20_EMC, /* Tegra20 memory controller */
122 COMPAT_NVIDIA_TEGRA20_EMC_TABLE, /* Tegra20 memory timing table */
123 COMPAT_NVIDIA_TEGRA20_KBC, /* Tegra20 Keyboard */
124 COMPAT_NVIDIA_TEGRA20_NAND, /* Tegra2 NAND controller */
125 COMPAT_NVIDIA_TEGRA20_PWM, /* Tegra 2 PWM controller */
126 COMPAT_NVIDIA_TEGRA20_DC, /* Tegra 2 Display controller */
127 COMPAT_NVIDIA_TEGRA124_SDMMC, /* Tegra124 SDMMC controller */
128 COMPAT_NVIDIA_TEGRA30_SDMMC, /* Tegra30 SDMMC controller */
129 COMPAT_NVIDIA_TEGRA20_SDMMC, /* Tegra20 SDMMC controller */
130 COMPAT_NVIDIA_TEGRA20_SFLASH, /* Tegra 2 SPI flash controller */
131 COMPAT_NVIDIA_TEGRA20_SLINK, /* Tegra 2 SPI SLINK controller */
132 COMPAT_NVIDIA_TEGRA114_SPI, /* Tegra 114 SPI controller */
133 COMPAT_NVIDIA_TEGRA124_PCIE, /* Tegra 124 PCIe controller */
134 COMPAT_NVIDIA_TEGRA30_PCIE, /* Tegra 30 PCIe controller */
135 COMPAT_NVIDIA_TEGRA20_PCIE, /* Tegra 20 PCIe controller */
136 COMPAT_NVIDIA_TEGRA124_XUSB_PADCTL,
137 /* Tegra124 XUSB pad controller */
138 COMPAT_SMSC_LAN9215, /* SMSC 10/100 Ethernet LAN9215 */
139 COMPAT_SAMSUNG_EXYNOS5_SROMC, /* Exynos5 SROMC */
140 COMPAT_SAMSUNG_S3C2440_I2C, /* Exynos I2C Controller */
141 COMPAT_SAMSUNG_EXYNOS5_SOUND, /* Exynos Sound */
142 COMPAT_WOLFSON_WM8994_CODEC, /* Wolfson WM8994 Sound Codec */
143 COMPAT_SAMSUNG_EXYNOS_SPI, /* Exynos SPI */
144 COMPAT_GOOGLE_CROS_EC, /* Google CROS_EC Protocol */
145 COMPAT_GOOGLE_CROS_EC_KEYB, /* Google CROS_EC Keyboard */
146 COMPAT_SAMSUNG_EXYNOS_EHCI, /* Exynos EHCI controller */
147 COMPAT_SAMSUNG_EXYNOS5_XHCI, /* Exynos5 XHCI controller */
148 COMPAT_SAMSUNG_EXYNOS_USB_PHY, /* Exynos phy controller for usb2.0 */
149 COMPAT_SAMSUNG_EXYNOS5_USB3_PHY,/* Exynos phy controller for usb3.0 */
150 COMPAT_SAMSUNG_EXYNOS_TMU, /* Exynos TMU */
151 COMPAT_SAMSUNG_EXYNOS_FIMD, /* Exynos Display controller */
152 COMPAT_SAMSUNG_EXYNOS_MIPI_DSI, /* Exynos mipi dsi */
153 COMPAT_SAMSUNG_EXYNOS5_DP, /* Exynos Display port controller */
154 COMPAT_SAMSUNG_EXYNOS_DWMMC, /* Exynos DWMMC controller */
155 COMPAT_SAMSUNG_EXYNOS_MMC, /* Exynos MMC controller */
156 COMPAT_SAMSUNG_EXYNOS_SERIAL, /* Exynos UART */
157 COMPAT_MAXIM_MAX77686_PMIC, /* MAX77686 PMIC */
158 COMPAT_GENERIC_SPI_FLASH, /* Generic SPI Flash chip */
159 COMPAT_MAXIM_98095_CODEC, /* MAX98095 Codec */
160 COMPAT_INFINEON_SLB9635_TPM, /* Infineon SLB9635 TPM */
161 COMPAT_INFINEON_SLB9645_TPM, /* Infineon SLB9645 TPM */
162 COMPAT_SAMSUNG_EXYNOS5_I2C, /* Exynos5 High Speed I2C Controller */
163 COMPAT_SANDBOX_HOST_EMULATION, /* Sandbox emulation of a function */
164 COMPAT_SANDBOX_LCD_SDL, /* Sandbox LCD emulation with SDL */
165 COMPAT_TI_TPS65090, /* Texas Instrument TPS65090 */
166 COMPAT_NXP_PTN3460, /* NXP PTN3460 DP/LVDS bridge */
167 COMPAT_SAMSUNG_EXYNOS_SYSMMU, /* Exynos sysmmu */
168 COMPAT_PARADE_PS8625, /* Parade PS8622 EDP->LVDS bridge */
169 COMPAT_INTEL_LPC, /* Intel Low Pin Count I/F */
170 COMPAT_INTEL_MICROCODE, /* Intel microcode update */
171 COMPAT_MEMORY_SPD, /* Memory SPD information */
172 COMPAT_INTEL_PANTHERPOINT_AHCI, /* Intel Pantherpoint AHCI */
173 COMPAT_INTEL_MODEL_206AX, /* Intel Model 206AX CPU */
174 COMPAT_INTEL_GMA, /* Intel Graphics Media Accelerator */
175 COMPAT_AMS_AS3722, /* AMS AS3722 PMIC */
176 COMPAT_INTEL_ICH_SPI, /* Intel ICH7/9 SPI controller */
181 /* GPIOs are numbered from 0 */
183 FDT_GPIO_NONE = -1U, /* an invalid GPIO used to end our list */
185 FDT_GPIO_ACTIVE_LOW = 1 << 0, /* input is active low (else high) */
188 /* This is the state of a GPIO pin as defined by the fdt */
189 struct fdt_gpio_state {
190 const char *name; /* name of the fdt property defining this */
191 uint gpio; /* GPIO number, or FDT_GPIO_NONE if none */
192 u8 flags; /* FDT_GPIO_... flags */
195 /* This tells us whether a fdt_gpio_state record is valid or not */
196 #define fdt_gpio_isvalid(x) ((x)->gpio != FDT_GPIO_NONE)
199 * Read the GPIO taking into account the polarity of the pin.
201 * @param gpio pointer to the decoded gpio
202 * @return value of the gpio if successful, < 0 if unsuccessful
204 int fdtdec_get_gpio(struct fdt_gpio_state *gpio);
207 * Write the GPIO taking into account the polarity of the pin.
209 * @param gpio pointer to the decoded gpio
210 * @return 0 if successful
212 int fdtdec_set_gpio(struct fdt_gpio_state *gpio, int val);
215 * Find the next numbered alias for a peripheral. This is used to enumerate
216 * all the peripherals of a certain type.
218 * Do the first call with *upto = 0. Assuming /aliases/<name>0 exists then
219 * this function will return a pointer to the node the alias points to, and
220 * then update *upto to 1. Next time you call this function, the next node
223 * All nodes returned will match the compatible ID, as it is assumed that
224 * all peripherals use the same driver.
226 * @param blob FDT blob to use
227 * @param name Root name of alias to search for
228 * @param id Compatible ID to look for
229 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
231 int fdtdec_next_alias(const void *blob, const char *name,
232 enum fdt_compat_id id, int *upto);
235 * Find the compatible ID for a given node.
237 * Generally each node has at least one compatible string attached to it.
238 * This function looks through our list of known compatible strings and
239 * returns the corresponding ID which matches the compatible string.
241 * @param blob FDT blob to use
242 * @param node Node containing compatible string to find
243 * @return compatible ID, or COMPAT_UNKNOWN if we cannot find a match
245 enum fdt_compat_id fdtdec_lookup(const void *blob, int node);
248 * Find the next compatible node for a peripheral.
250 * Do the first call with node = 0. This function will return a pointer to
251 * the next compatible node. Next time you call this function, pass the
252 * value returned, and the next node will be provided.
254 * @param blob FDT blob to use
255 * @param node Start node for search
256 * @param id Compatible ID to look for (enum fdt_compat_id)
257 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
259 int fdtdec_next_compatible(const void *blob, int node,
260 enum fdt_compat_id id);
263 * Find the next compatible subnode for a peripheral.
265 * Do the first call with node set to the parent and depth = 0. This
266 * function will return the offset of the next compatible node. Next time
267 * you call this function, pass the node value returned last time, with
268 * depth unchanged, and the next node will be provided.
270 * @param blob FDT blob to use
271 * @param node Start node for search
272 * @param id Compatible ID to look for (enum fdt_compat_id)
273 * @param depthp Current depth (set to 0 before first call)
274 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
276 int fdtdec_next_compatible_subnode(const void *blob, int node,
277 enum fdt_compat_id id, int *depthp);
280 * Look up an address property in a node and return it as an address.
281 * The property must hold either one address with no trailing data or
282 * one address with a length. This is only tested on 32-bit machines.
284 * @param blob FDT blob
285 * @param node node to examine
286 * @param prop_name name of property to find
287 * @return address, if found, or FDT_ADDR_T_NONE if not
289 fdt_addr_t fdtdec_get_addr(const void *blob, int node,
290 const char *prop_name);
293 * Look up an address property in a node and return it as an address.
294 * The property must hold one address with a length. This is only tested
295 * on 32-bit machines.
297 * @param blob FDT blob
298 * @param node node to examine
299 * @param prop_name name of property to find
300 * @return address, if found, or FDT_ADDR_T_NONE if not
302 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
303 const char *prop_name, fdt_size_t *sizep);
306 * Look at an address property in a node and return the pci address which
307 * corresponds to the given type in the form of fdt_pci_addr.
308 * The property must hold one fdt_pci_addr with a lengh.
310 * @param blob FDT blob
311 * @param node node to examine
312 * @param type pci address type (FDT_PCI_SPACE_xxx)
313 * @param prop_name name of property to find
314 * @param addr returns pci address in the form of fdt_pci_addr
315 * @return 0 if ok, negative on error
317 int fdtdec_get_pci_addr(const void *blob, int node, enum fdt_pci_space type,
318 const char *prop_name, struct fdt_pci_addr *addr);
321 * Look at the compatible property of a device node that represents a PCI
322 * device and extract pci vendor id and device id from it.
324 * @param blob FDT blob
325 * @param node node to examine
326 * @param vendor vendor id of the pci device
327 * @param device device id of the pci device
328 * @return 0 if ok, negative on error
330 int fdtdec_get_pci_vendev(const void *blob, int node,
331 u16 *vendor, u16 *device);
334 * Look at the pci address of a device node that represents a PCI device
335 * and parse the bus, device and function number from it.
337 * @param blob FDT blob
338 * @param node node to examine
339 * @param addr pci address in the form of fdt_pci_addr
340 * @param bdf returns bus, device, function triplet
341 * @return 0 if ok, negative on error
343 int fdtdec_get_pci_bdf(const void *blob, int node,
344 struct fdt_pci_addr *addr, pci_dev_t *bdf);
347 * Look at the pci address of a device node that represents a PCI device
348 * and return base address of the pci device's registers.
350 * @param blob FDT blob
351 * @param node node to examine
352 * @param addr pci address in the form of fdt_pci_addr
353 * @param bar returns base address of the pci device's registers
354 * @return 0 if ok, negative on error
356 int fdtdec_get_pci_bar32(const void *blob, int node,
357 struct fdt_pci_addr *addr, u32 *bar);
360 * Look up a 32-bit integer property in a node and return it. The property
361 * must have at least 4 bytes of data. The value of the first cell is
364 * @param blob FDT blob
365 * @param node node to examine
366 * @param prop_name name of property to find
367 * @param default_val default value to return if the property is not found
368 * @return integer value, if found, or default_val if not
370 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
374 * Look up a 64-bit integer property in a node and return it. The property
375 * must have at least 8 bytes of data (2 cells). The first two cells are
376 * concatenated to form a 8 bytes value, where the first cell is top half and
377 * the second cell is bottom half.
379 * @param blob FDT blob
380 * @param node node to examine
381 * @param prop_name name of property to find
382 * @param default_val default value to return if the property is not found
383 * @return integer value, if found, or default_val if not
385 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
386 uint64_t default_val);
389 * Checks whether a node is enabled.
390 * This looks for a 'status' property. If this exists, then returns 1 if
391 * the status is 'ok' and 0 otherwise. If there is no status property,
392 * it returns 1 on the assumption that anything mentioned should be enabled
395 * @param blob FDT blob
396 * @param node node to examine
397 * @return integer value 0 (not enabled) or 1 (enabled)
399 int fdtdec_get_is_enabled(const void *blob, int node);
402 * Make sure we have a valid fdt available to control U-Boot.
404 * If not, a message is printed to the console if the console is ready.
406 * @return 0 if all ok, -1 if not
408 int fdtdec_prepare_fdt(void);
411 * Checks that we have a valid fdt available to control U-Boot.
413 * However, if not then for the moment nothing is done, since this function
414 * is called too early to panic().
418 int fdtdec_check_fdt(void);
421 * Find the nodes for a peripheral and return a list of them in the correct
422 * order. This is used to enumerate all the peripherals of a certain type.
424 * To use this, optionally set up a /aliases node with alias properties for
425 * a peripheral. For example, for usb you could have:
428 * usb0 = "/ehci@c5008000";
429 * usb1 = "/ehci@c5000000";
432 * Pass "usb" as the name to this function and will return a list of two
433 * nodes offsets: /ehci@c5008000 and ehci@c5000000.
435 * All nodes returned will match the compatible ID, as it is assumed that
436 * all peripherals use the same driver.
438 * If no alias node is found, then the node list will be returned in the
439 * order found in the fdt. If the aliases mention a node which doesn't
440 * exist, then this will be ignored. If nodes are found with no aliases,
441 * they will be added in any order.
443 * If there is a gap in the aliases, then this function return a 0 node at
444 * that position. The return value will also count these gaps.
446 * This function checks node properties and will not return nodes which are
447 * marked disabled (status = "disabled").
449 * @param blob FDT blob to use
450 * @param name Root name of alias to search for
451 * @param id Compatible ID to look for
452 * @param node_list Place to put list of found nodes
453 * @param maxcount Maximum number of nodes to find
454 * @return number of nodes found on success, FTD_ERR_... on error
456 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
457 enum fdt_compat_id id, int *node_list, int maxcount);
460 * This function is similar to fdtdec_find_aliases_for_id() except that it
461 * adds to the node_list that is passed in. Any 0 elements are considered
462 * available for allocation - others are considered already used and are
465 * You can use this by calling fdtdec_find_aliases_for_id() with an
466 * uninitialised array, then setting the elements that are returned to -1,
467 * say, then calling this function, perhaps with a different compat id.
468 * Any elements you get back that are >0 are new nodes added by the call
471 * Note that if you have some nodes with aliases and some without, you are
472 * sailing close to the wind. The call to fdtdec_find_aliases_for_id() with
473 * one compat_id may fill in positions for which you have aliases defined
474 * for another compat_id. When you later call *this* function with the second
475 * compat_id, the alias positions may already be used. A debug warning may
476 * be generated in this case, but it is safest to define aliases for all
477 * nodes when you care about the ordering.
479 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
480 enum fdt_compat_id id, int *node_list, int maxcount);
483 * Get the alias sequence number of a node
485 * This works out whether a node is pointed to by an alias, and if so, the
486 * sequence number of that alias. Aliases are of the form <base><num> where
487 * <num> is the sequence number. For example spi2 would be sequence number
490 * @param blob Device tree blob (if NULL, then error is returned)
491 * @param base Base name for alias (before the underscore)
492 * @param node Node to look up
493 * @param seqp This is set to the sequence number if one is found,
494 * but otherwise the value is left alone
495 * @return 0 if a sequence was found, -ve if not
497 int fdtdec_get_alias_seq(const void *blob, const char *base, int node,
501 * Get the offset of the given chosen node
503 * This looks up a property in /chosen containing the path to another node,
504 * then finds the offset of that node.
506 * @param blob Device tree blob (if NULL, then error is returned)
507 * @param name Property name, e.g. "stdout-path"
508 * @return Node offset referred to by that chosen node, or -ve FDT_ERR_...
510 int fdtdec_get_chosen_node(const void *blob, const char *name);
513 * Get the name for a compatible ID
515 * @param id Compatible ID to look for
516 * @return compatible string for that id
518 const char *fdtdec_get_compatible(enum fdt_compat_id id);
520 /* Look up a phandle and follow it to its node. Then return the offset
523 * @param blob FDT blob
524 * @param node node to examine
525 * @param prop_name name of property to find
526 * @return node offset if found, -ve error code on error
528 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name);
531 * Look up a property in a node and return its contents in an integer
532 * array of given length. The property must have at least enough data for
533 * the array (4*count bytes). It may have more, but this will be ignored.
535 * @param blob FDT blob
536 * @param node node to examine
537 * @param prop_name name of property to find
538 * @param array array to fill with data
539 * @param count number of array elements
540 * @return 0 if ok, or -FDT_ERR_NOTFOUND if the property is not found,
541 * or -FDT_ERR_BADLAYOUT if not enough data
543 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
544 u32 *array, int count);
547 * Look up a property in a node and return its contents in an integer
548 * array of given length. The property must exist but may have less data that
549 * expected (4*count bytes). It may have more, but this will be ignored.
551 * @param blob FDT blob
552 * @param node node to examine
553 * @param prop_name name of property to find
554 * @param array array to fill with data
555 * @param count number of array elements
556 * @return number of array elements if ok, or -FDT_ERR_NOTFOUND if the
557 * property is not found
559 int fdtdec_get_int_array_count(const void *blob, int node,
560 const char *prop_name, u32 *array, int count);
563 * Look up a property in a node and return a pointer to its contents as a
564 * unsigned int array of given length. The property must have at least enough
565 * data for the array ('count' cells). It may have more, but this will be
566 * ignored. The data is not copied.
568 * Note that you must access elements of the array with fdt32_to_cpu(),
569 * since the elements will be big endian even on a little endian machine.
571 * @param blob FDT blob
572 * @param node node to examine
573 * @param prop_name name of property to find
574 * @param count number of array elements
575 * @return pointer to array if found, or NULL if the property is not
576 * found or there is not enough data
578 const u32 *fdtdec_locate_array(const void *blob, int node,
579 const char *prop_name, int count);
582 * Look up a boolean property in a node and return it.
584 * A boolean properly is true if present in the device tree and false if not
585 * present, regardless of its value.
587 * @param blob FDT blob
588 * @param node node to examine
589 * @param prop_name name of property to find
590 * @return 1 if the properly is present; 0 if it isn't present
592 int fdtdec_get_bool(const void *blob, int node, const char *prop_name);
595 * Decode a single GPIOs from an FDT.
597 * If the property is not found, then the GPIO structure will still be
598 * initialised, with gpio set to FDT_GPIO_NONE. This makes it easy to
599 * provide optional GPIOs.
601 * @param blob FDT blob to use
602 * @param node Node to look at
603 * @param prop_name Node property name
604 * @param gpio gpio elements to fill from FDT
605 * @return 0 if ok, -FDT_ERR_NOTFOUND if the property is missing.
607 int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name,
608 struct fdt_gpio_state *gpio);
611 * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no
614 * @param blob FDT blob to use
615 * @param node Node to look at
616 * @param prop_name Node property name
617 * @param gpio Array of gpio elements to fill from FDT. This will be
618 * untouched if either 0 or an error is returned
619 * @param max_count Maximum number of elements allowed
620 * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would
621 * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing.
623 int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name,
624 struct fdt_gpio_state *gpio, int max_count);
627 * Set up a GPIO pin according to the provided gpio information. At present this
628 * just requests the GPIO.
630 * If the gpio is FDT_GPIO_NONE, no action is taken. This makes it easy to
631 * deal with optional GPIOs.
633 * @param gpio GPIO info to use for set up
634 * @return 0 if all ok or gpio was FDT_GPIO_NONE; -1 on error
636 int fdtdec_setup_gpio(struct fdt_gpio_state *gpio);
639 * Look in the FDT for a config item with the given name and return its value
640 * as a 32-bit integer. The property must have at least 4 bytes of data. The
641 * value of the first cell is returned.
643 * @param blob FDT blob to use
644 * @param prop_name Node property name
645 * @param default_val default value to return if the property is not found
646 * @return integer value, if found, or default_val if not
648 int fdtdec_get_config_int(const void *blob, const char *prop_name,
652 * Look in the FDT for a config item with the given name
653 * and return whether it exists.
655 * @param blob FDT blob
656 * @param prop_name property name to look up
657 * @return 1, if it exists, or 0 if not
659 int fdtdec_get_config_bool(const void *blob, const char *prop_name);
662 * Look in the FDT for a config item with the given name and return its value
665 * @param blob FDT blob
666 * @param prop_name property name to look up
667 * @returns property string, NULL on error.
669 char *fdtdec_get_config_string(const void *blob, const char *prop_name);
672 * Look up a property in a node and return its contents in a byte
673 * array of given length. The property must have at least enough data for
674 * the array (count bytes). It may have more, but this will be ignored.
676 * @param blob FDT blob
677 * @param node node to examine
678 * @param prop_name name of property to find
679 * @param array array to fill with data
680 * @param count number of array elements
681 * @return 0 if ok, or -FDT_ERR_MISSING if the property is not found,
682 * or -FDT_ERR_BADLAYOUT if not enough data
684 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
685 u8 *array, int count);
688 * Look up a property in a node and return a pointer to its contents as a
689 * byte array of given length. The property must have at least enough data
690 * for the array (count bytes). It may have more, but this will be ignored.
691 * The data is not copied.
693 * @param blob FDT blob
694 * @param node node to examine
695 * @param prop_name name of property to find
696 * @param count number of array elements
697 * @return pointer to byte array if found, or NULL if the property is not
698 * found or there is not enough data
700 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
701 const char *prop_name, int count);
704 * Look up a property in a node which contains a memory region address and
705 * size. Then return a pointer to this address.
707 * The property must hold one address with a length. This is only tested on
710 * @param blob FDT blob
711 * @param node node to examine
712 * @param prop_name name of property to find
713 * @param basep Returns base address of region
714 * @param size Returns size of region
715 * @return 0 if ok, -1 on error (property not found)
717 int fdtdec_decode_region(const void *blob, int node, const char *prop_name,
718 fdt_addr_t *basep, fdt_size_t *sizep);
720 enum fmap_compress_t {
731 /* A flash map entry, containing an offset and length */
735 uint32_t used; /* Number of bytes used in region */
736 enum fmap_compress_t compress_algo; /* Compression type */
737 enum fmap_hash_t hash_algo; /* Hash algorithm */
738 const uint8_t *hash; /* Hash value */
739 int hash_size; /* Hash size */
743 * Read a flash entry from the fdt
745 * @param blob FDT blob
746 * @param node Offset of node to read
747 * @param name Name of node being read
748 * @param entry Place to put offset and size of this node
749 * @return 0 if ok, -ve on error
751 int fdtdec_read_fmap_entry(const void *blob, int node, const char *name,
752 struct fmap_entry *entry);
755 * Obtain an indexed resource from a device property.
757 * @param fdt FDT blob
758 * @param node node to examine
759 * @param property name of the property to parse
760 * @param index index of the resource to retrieve
761 * @param res returns the resource
762 * @return 0 if ok, negative on error
764 int fdt_get_resource(const void *fdt, int node, const char *property,
765 unsigned int index, struct fdt_resource *res);
768 * Obtain a named resource from a device property.
770 * Look up the index of the name in a list of strings and return the resource
773 * @param fdt FDT blob
774 * @param node node to examine
775 * @param property name of the property to parse
776 * @param prop_names name of the property containing the list of names
777 * @param name the name of the entry to look up
778 * @param res returns the resource
780 int fdt_get_named_resource(const void *fdt, int node, const char *property,
781 const char *prop_names, const char *name,
782 struct fdt_resource *res);
785 * Decode a named region within a memory bank of a given type.
787 * This function handles selection of a memory region. The region is
788 * specified as an offset/size within a particular type of memory.
790 * The properties used are:
792 * <mem_type>-memory<suffix> for the name of the memory bank
793 * <mem_type>-offset<suffix> for the offset in that bank
795 * The property value must have an offset and a size. The function checks
796 * that the region is entirely within the memory bank.5
798 * @param blob FDT blob
799 * @param node Node containing the properties (-1 for /config)
800 * @param mem_type Type of memory to use, which is a name, such as
801 * "u-boot" or "kernel".
802 * @param suffix String to append to the memory/offset
804 * @param basep Returns base of region
805 * @param sizep Returns size of region
806 * @return 0 if OK, -ive on error
808 int fdtdec_decode_memory_region(const void *blob, int node,
809 const char *mem_type, const char *suffix,
810 fdt_addr_t *basep, fdt_size_t *sizep);