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 typedef phys_addr_t fdt_addr_t;
25 typedef phys_size_t fdt_size_t;
26 #ifdef CONFIG_PHYS_64BIT
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 #define FDT_ADDR_T_NONE (-1U)
32 #define fdt_addr_to_cpu(reg) be32_to_cpu(reg)
33 #define fdt_size_to_cpu(reg) be32_to_cpu(reg)
36 /* Information obtained about memory from the FDT */
42 #ifdef CONFIG_SPL_BUILD
48 #ifdef CONFIG_OF_CONTROL
49 # if defined(CONFIG_SPL_BUILD) && defined(SPL_DISABLE_OF_CONTROL)
59 * Information about a resource. start is the first address of the resource
60 * and end is the last address (inclusive). The length of the resource will
61 * be equal to: end - start + 1.
69 FDT_PCI_SPACE_CONFIG = 0,
70 FDT_PCI_SPACE_IO = 0x01000000,
71 FDT_PCI_SPACE_MEM32 = 0x02000000,
72 FDT_PCI_SPACE_MEM64 = 0x03000000,
73 FDT_PCI_SPACE_MEM32_PREF = 0x42000000,
74 FDT_PCI_SPACE_MEM64_PREF = 0x43000000,
77 #define FDT_PCI_ADDR_CELLS 3
78 #define FDT_PCI_SIZE_CELLS 2
79 #define FDT_PCI_REG_SIZE \
80 ((FDT_PCI_ADDR_CELLS + FDT_PCI_SIZE_CELLS) * sizeof(u32))
83 * The Open Firmware spec defines PCI physical address as follows:
85 * bits# 31 .... 24 23 .... 16 15 .... 08 07 .... 00
87 * phys.hi cell: npt000ss bbbbbbbb dddddfff rrrrrrrr
88 * phys.mid cell: hhhhhhhh hhhhhhhh hhhhhhhh hhhhhhhh
89 * phys.lo cell: llllllll llllllll llllllll llllllll
93 * n: is 0 if the address is relocatable, 1 otherwise
94 * p: is 1 if addressable region is prefetchable, 0 otherwise
95 * t: is 1 if the address is aliased (for non-relocatable I/O) below 1MB
96 * (for Memory), or below 64KB (for relocatable I/O)
97 * ss: is the space code, denoting the address space
98 * bbbbbbbb: is the 8-bit Bus Number
99 * ddddd: is the 5-bit Device Number
100 * fff: is the 3-bit Function Number
101 * rrrrrrrr: is the 8-bit Register Number
102 * hhhhhhhh: is a 32-bit unsigned number
103 * llllllll: is a 32-bit unsigned number
105 struct fdt_pci_addr {
112 * Compute the size of a resource.
114 * @param res the resource to operate on
115 * @return the size of the resource
117 static inline fdt_size_t fdt_resource_size(const struct fdt_resource *res)
119 return res->end - res->start + 1;
123 * Compat types that we know about and for which we might have drivers.
124 * Each is named COMPAT_<dir>_<filename> where <dir> is the directory
129 COMPAT_NVIDIA_TEGRA20_EMC, /* Tegra20 memory controller */
130 COMPAT_NVIDIA_TEGRA20_EMC_TABLE, /* Tegra20 memory timing table */
131 COMPAT_NVIDIA_TEGRA20_KBC, /* Tegra20 Keyboard */
132 COMPAT_NVIDIA_TEGRA20_NAND, /* Tegra2 NAND controller */
133 COMPAT_NVIDIA_TEGRA20_PWM, /* Tegra 2 PWM controller */
134 COMPAT_NVIDIA_TEGRA124_DC, /* Tegra 124 Display controller */
135 COMPAT_NVIDIA_TEGRA124_SOR, /* Tegra 124 Serial Output Resource */
136 COMPAT_NVIDIA_TEGRA124_PMC, /* Tegra 124 power mgmt controller */
137 COMPAT_NVIDIA_TEGRA20_DC, /* Tegra 2 Display controller */
138 COMPAT_NVIDIA_TEGRA210_SDMMC, /* Tegra210 SDMMC controller */
139 COMPAT_NVIDIA_TEGRA124_SDMMC, /* Tegra124 SDMMC controller */
140 COMPAT_NVIDIA_TEGRA30_SDMMC, /* Tegra30 SDMMC controller */
141 COMPAT_NVIDIA_TEGRA20_SDMMC, /* Tegra20 SDMMC controller */
142 COMPAT_NVIDIA_TEGRA124_PCIE, /* Tegra 124 PCIe controller */
143 COMPAT_NVIDIA_TEGRA30_PCIE, /* Tegra 30 PCIe controller */
144 COMPAT_NVIDIA_TEGRA20_PCIE, /* Tegra 20 PCIe controller */
145 COMPAT_NVIDIA_TEGRA124_XUSB_PADCTL,
146 /* Tegra124 XUSB pad controller */
147 COMPAT_NVIDIA_TEGRA210_XUSB_PADCTL,
148 /* Tegra210 XUSB pad controller */
149 COMPAT_SMSC_LAN9215, /* SMSC 10/100 Ethernet LAN9215 */
150 COMPAT_SAMSUNG_EXYNOS5_SROMC, /* Exynos5 SROMC */
151 COMPAT_SAMSUNG_S3C2440_I2C, /* Exynos I2C Controller */
152 COMPAT_SAMSUNG_EXYNOS5_SOUND, /* Exynos Sound */
153 COMPAT_WOLFSON_WM8994_CODEC, /* Wolfson WM8994 Sound Codec */
154 COMPAT_GOOGLE_CROS_EC_KEYB, /* Google CROS_EC Keyboard */
155 COMPAT_SAMSUNG_EXYNOS_USB_PHY, /* Exynos phy controller for usb2.0 */
156 COMPAT_SAMSUNG_EXYNOS5_USB3_PHY,/* Exynos phy controller for usb3.0 */
157 COMPAT_SAMSUNG_EXYNOS_TMU, /* Exynos TMU */
158 COMPAT_SAMSUNG_EXYNOS_FIMD, /* Exynos Display controller */
159 COMPAT_SAMSUNG_EXYNOS_MIPI_DSI, /* Exynos mipi dsi */
160 COMPAT_SAMSUNG_EXYNOS5_DP, /* Exynos Display port controller */
161 COMPAT_SAMSUNG_EXYNOS_DWMMC, /* Exynos DWMMC controller */
162 COMPAT_SAMSUNG_EXYNOS_MMC, /* Exynos MMC controller */
163 COMPAT_SAMSUNG_EXYNOS_SERIAL, /* Exynos UART */
164 COMPAT_MAXIM_MAX77686_PMIC, /* MAX77686 PMIC */
165 COMPAT_GENERIC_SPI_FLASH, /* Generic SPI Flash chip */
166 COMPAT_MAXIM_98095_CODEC, /* MAX98095 Codec */
167 COMPAT_INFINEON_SLB9635_TPM, /* Infineon SLB9635 TPM */
168 COMPAT_INFINEON_SLB9645_TPM, /* Infineon SLB9645 TPM */
169 COMPAT_SAMSUNG_EXYNOS5_I2C, /* Exynos5 High Speed I2C Controller */
170 COMPAT_SANDBOX_LCD_SDL, /* Sandbox LCD emulation with SDL */
171 COMPAT_SAMSUNG_EXYNOS_SYSMMU, /* Exynos sysmmu */
172 COMPAT_INTEL_MICROCODE, /* Intel microcode update */
173 COMPAT_MEMORY_SPD, /* Memory SPD information */
174 COMPAT_INTEL_PANTHERPOINT_AHCI, /* Intel Pantherpoint AHCI */
175 COMPAT_INTEL_MODEL_206AX, /* Intel Model 206AX CPU */
176 COMPAT_INTEL_GMA, /* Intel Graphics Media Accelerator */
177 COMPAT_AMS_AS3722, /* AMS AS3722 PMIC */
178 COMPAT_INTEL_ICH_SPI, /* Intel ICH7/9 SPI controller */
179 COMPAT_INTEL_QRK_MRC, /* Intel Quark MRC */
180 COMPAT_INTEL_X86_PINCTRL, /* Intel ICH7/9 pin control */
181 COMPAT_SOCIONEXT_XHCI, /* Socionext UniPhier xHCI */
182 COMPAT_INTEL_PCH, /* Intel PCH */
183 COMPAT_INTEL_IRQ_ROUTER, /* Intel Interrupt Router */
188 #define MAX_PHANDLE_ARGS 16
189 struct fdtdec_phandle_args {
192 uint32_t args[MAX_PHANDLE_ARGS];
196 * fdtdec_parse_phandle_with_args() - Find a node pointed by phandle in a list
198 * This function is useful to parse lists of phandles and their arguments.
211 * list = <&phandle1 1 2 &phandle2 3>;
214 * To get a device_node of the `node2' node you may call this:
215 * fdtdec_parse_phandle_with_args(blob, node3, "list", "#list-cells", 0, 1,
218 * (This function is a modified version of __of_parse_phandle_with_args() from
221 * @blob: Pointer to device tree
222 * @src_node: Offset of device tree node containing a list
223 * @list_name: property name that contains a list
224 * @cells_name: property name that specifies the phandles' arguments count,
225 * or NULL to use @cells_count
226 * @cells_count: Cell count to use if @cells_name is NULL
227 * @index: index of a phandle to parse out
228 * @out_args: optional pointer to output arguments structure (will be filled)
229 * @return 0 on success (with @out_args filled out if not NULL), -ENOENT if
230 * @list_name does not exist, a phandle was not found, @cells_name
231 * could not be found, the arguments were truncated or there were too
235 int fdtdec_parse_phandle_with_args(const void *blob, int src_node,
236 const char *list_name,
237 const char *cells_name,
238 int cell_count, int index,
239 struct fdtdec_phandle_args *out_args);
242 * Find the next numbered alias for a peripheral. This is used to enumerate
243 * all the peripherals of a certain type.
245 * Do the first call with *upto = 0. Assuming /aliases/<name>0 exists then
246 * this function will return a pointer to the node the alias points to, and
247 * then update *upto to 1. Next time you call this function, the next node
250 * All nodes returned will match the compatible ID, as it is assumed that
251 * all peripherals use the same driver.
253 * @param blob FDT blob to use
254 * @param name Root name of alias to search for
255 * @param id Compatible ID to look for
256 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
258 int fdtdec_next_alias(const void *blob, const char *name,
259 enum fdt_compat_id id, int *upto);
262 * Find the compatible ID for a given node.
264 * Generally each node has at least one compatible string attached to it.
265 * This function looks through our list of known compatible strings and
266 * returns the corresponding ID which matches the compatible string.
268 * @param blob FDT blob to use
269 * @param node Node containing compatible string to find
270 * @return compatible ID, or COMPAT_UNKNOWN if we cannot find a match
272 enum fdt_compat_id fdtdec_lookup(const void *blob, int node);
275 * Find the next compatible node for a peripheral.
277 * Do the first call with node = 0. This function will return a pointer to
278 * the next compatible node. Next time you call this function, pass the
279 * value returned, and the next node will be provided.
281 * @param blob FDT blob to use
282 * @param node Start node for search
283 * @param id Compatible ID to look for (enum fdt_compat_id)
284 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
286 int fdtdec_next_compatible(const void *blob, int node,
287 enum fdt_compat_id id);
290 * Find the next compatible subnode for a peripheral.
292 * Do the first call with node set to the parent and depth = 0. This
293 * function will return the offset of the next compatible node. Next time
294 * you call this function, pass the node value returned last time, with
295 * depth unchanged, and the next node will be provided.
297 * @param blob FDT blob to use
298 * @param node Start node for search
299 * @param id Compatible ID to look for (enum fdt_compat_id)
300 * @param depthp Current depth (set to 0 before first call)
301 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
303 int fdtdec_next_compatible_subnode(const void *blob, int node,
304 enum fdt_compat_id id, int *depthp);
307 * Look up an address property in a node and return it as an address.
308 * The property must hold either one address with no trailing data or
309 * one address with a length. This is only tested on 32-bit machines.
311 * @param blob FDT blob
312 * @param node node to examine
313 * @param prop_name name of property to find
314 * @return address, if found, or FDT_ADDR_T_NONE if not
316 fdt_addr_t fdtdec_get_addr(const void *blob, int node,
317 const char *prop_name);
320 * Look up an address property in a node and return it as an address.
321 * The property must hold one address with a length. This is only tested
322 * on 32-bit machines.
324 * @param blob FDT blob
325 * @param node node to examine
326 * @param prop_name name of property to find
327 * @return address, if found, or FDT_ADDR_T_NONE if not
329 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
330 const char *prop_name, fdt_size_t *sizep);
333 * Look at an address property in a node and return the pci address which
334 * corresponds to the given type in the form of fdt_pci_addr.
335 * The property must hold one fdt_pci_addr with a lengh.
337 * @param blob FDT blob
338 * @param node node to examine
339 * @param type pci address type (FDT_PCI_SPACE_xxx)
340 * @param prop_name name of property to find
341 * @param addr returns pci address in the form of fdt_pci_addr
342 * @return 0 if ok, -ENOENT if the property did not exist, -EINVAL if the
343 * format of the property was invalid, -ENXIO if the requested
344 * address type was not found
346 int fdtdec_get_pci_addr(const void *blob, int node, enum fdt_pci_space type,
347 const char *prop_name, struct fdt_pci_addr *addr);
350 * Look at the compatible property of a device node that represents a PCI
351 * device and extract pci vendor id and device id from it.
353 * @param blob FDT blob
354 * @param node node to examine
355 * @param vendor vendor id of the pci device
356 * @param device device id of the pci device
357 * @return 0 if ok, negative on error
359 int fdtdec_get_pci_vendev(const void *blob, int node,
360 u16 *vendor, u16 *device);
363 * Look at the pci address of a device node that represents a PCI device
364 * and parse the bus, device and function number from it. For some cases
365 * like the bus number encoded in reg property is not correct after pci
366 * enumeration, this function looks through the node's compatible strings
367 * to get these numbers extracted instead.
369 * @param blob FDT blob
370 * @param node node to examine
371 * @param addr pci address in the form of fdt_pci_addr
372 * @param bdf returns bus, device, function triplet
373 * @return 0 if ok, negative on error
375 int fdtdec_get_pci_bdf(const void *blob, int node,
376 struct fdt_pci_addr *addr, pci_dev_t *bdf);
379 * Look at the pci address of a device node that represents a PCI device
380 * and return base address of the pci device's registers.
382 * @param blob FDT blob
383 * @param node node to examine
384 * @param addr pci address in the form of fdt_pci_addr
385 * @param bar returns base address of the pci device's registers
386 * @return 0 if ok, negative on error
388 int fdtdec_get_pci_bar32(const void *blob, int node,
389 struct fdt_pci_addr *addr, u32 *bar);
392 * Look up a 32-bit integer property in a node and return it. The property
393 * must have at least 4 bytes of data. The value of the first cell is
396 * @param blob FDT blob
397 * @param node node to examine
398 * @param prop_name name of property to find
399 * @param default_val default value to return if the property is not found
400 * @return integer value, if found, or default_val if not
402 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
406 * Get a variable-sized number from a property
408 * This reads a number from one or more cells.
410 * @param ptr Pointer to property
411 * @param cells Number of cells containing the number
412 * @return the value in the cells
414 u64 fdtdec_get_number(const fdt32_t *ptr, unsigned int cells);
417 * Look up a 64-bit integer property in a node and return it. The property
418 * must have at least 8 bytes of data (2 cells). The first two cells are
419 * concatenated to form a 8 bytes value, where the first cell is top half and
420 * the second cell is bottom half.
422 * @param blob FDT blob
423 * @param node node to examine
424 * @param prop_name name of property to find
425 * @param default_val default value to return if the property is not found
426 * @return integer value, if found, or default_val if not
428 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
429 uint64_t default_val);
432 * Checks whether a node is enabled.
433 * This looks for a 'status' property. If this exists, then returns 1 if
434 * the status is 'ok' and 0 otherwise. If there is no status property,
435 * it returns 1 on the assumption that anything mentioned should be enabled
438 * @param blob FDT blob
439 * @param node node to examine
440 * @return integer value 0 (not enabled) or 1 (enabled)
442 int fdtdec_get_is_enabled(const void *blob, int node);
445 * Make sure we have a valid fdt available to control U-Boot.
447 * If not, a message is printed to the console if the console is ready.
449 * @return 0 if all ok, -1 if not
451 int fdtdec_prepare_fdt(void);
454 * Checks that we have a valid fdt available to control U-Boot.
456 * However, if not then for the moment nothing is done, since this function
457 * is called too early to panic().
461 int fdtdec_check_fdt(void);
464 * Find the nodes for a peripheral and return a list of them in the correct
465 * order. This is used to enumerate all the peripherals of a certain type.
467 * To use this, optionally set up a /aliases node with alias properties for
468 * a peripheral. For example, for usb you could have:
471 * usb0 = "/ehci@c5008000";
472 * usb1 = "/ehci@c5000000";
475 * Pass "usb" as the name to this function and will return a list of two
476 * nodes offsets: /ehci@c5008000 and ehci@c5000000.
478 * All nodes returned will match the compatible ID, as it is assumed that
479 * all peripherals use the same driver.
481 * If no alias node is found, then the node list will be returned in the
482 * order found in the fdt. If the aliases mention a node which doesn't
483 * exist, then this will be ignored. If nodes are found with no aliases,
484 * they will be added in any order.
486 * If there is a gap in the aliases, then this function return a 0 node at
487 * that position. The return value will also count these gaps.
489 * This function checks node properties and will not return nodes which are
490 * marked disabled (status = "disabled").
492 * @param blob FDT blob to use
493 * @param name Root name of alias to search for
494 * @param id Compatible ID to look for
495 * @param node_list Place to put list of found nodes
496 * @param maxcount Maximum number of nodes to find
497 * @return number of nodes found on success, FTD_ERR_... on error
499 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
500 enum fdt_compat_id id, int *node_list, int maxcount);
503 * This function is similar to fdtdec_find_aliases_for_id() except that it
504 * adds to the node_list that is passed in. Any 0 elements are considered
505 * available for allocation - others are considered already used and are
508 * You can use this by calling fdtdec_find_aliases_for_id() with an
509 * uninitialised array, then setting the elements that are returned to -1,
510 * say, then calling this function, perhaps with a different compat id.
511 * Any elements you get back that are >0 are new nodes added by the call
514 * Note that if you have some nodes with aliases and some without, you are
515 * sailing close to the wind. The call to fdtdec_find_aliases_for_id() with
516 * one compat_id may fill in positions for which you have aliases defined
517 * for another compat_id. When you later call *this* function with the second
518 * compat_id, the alias positions may already be used. A debug warning may
519 * be generated in this case, but it is safest to define aliases for all
520 * nodes when you care about the ordering.
522 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
523 enum fdt_compat_id id, int *node_list, int maxcount);
526 * Get the alias sequence number of a node
528 * This works out whether a node is pointed to by an alias, and if so, the
529 * sequence number of that alias. Aliases are of the form <base><num> where
530 * <num> is the sequence number. For example spi2 would be sequence number
533 * @param blob Device tree blob (if NULL, then error is returned)
534 * @param base Base name for alias (before the underscore)
535 * @param node Node to look up
536 * @param seqp This is set to the sequence number if one is found,
537 * but otherwise the value is left alone
538 * @return 0 if a sequence was found, -ve if not
540 int fdtdec_get_alias_seq(const void *blob, const char *base, int node,
544 * Get the offset of the given chosen node
546 * This looks up a property in /chosen containing the path to another node,
547 * then finds the offset of that node.
549 * @param blob Device tree blob (if NULL, then error is returned)
550 * @param name Property name, e.g. "stdout-path"
551 * @return Node offset referred to by that chosen node, or -ve FDT_ERR_...
553 int fdtdec_get_chosen_node(const void *blob, const char *name);
556 * Get the name for a compatible ID
558 * @param id Compatible ID to look for
559 * @return compatible string for that id
561 const char *fdtdec_get_compatible(enum fdt_compat_id id);
563 /* Look up a phandle and follow it to its node. Then return the offset
566 * @param blob FDT blob
567 * @param node node to examine
568 * @param prop_name name of property to find
569 * @return node offset if found, -ve error code on error
571 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name);
574 * Look up a property in a node and return its contents in an integer
575 * array of given length. The property must have at least enough data for
576 * the array (4*count bytes). It may have more, but this will be ignored.
578 * @param blob FDT blob
579 * @param node node to examine
580 * @param prop_name name of property to find
581 * @param array array to fill with data
582 * @param count number of array elements
583 * @return 0 if ok, or -FDT_ERR_NOTFOUND if the property is not found,
584 * or -FDT_ERR_BADLAYOUT if not enough data
586 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
587 u32 *array, int count);
590 * Look up a property in a node and return its contents in an integer
591 * array of given length. The property must exist but may have less data that
592 * expected (4*count bytes). It may have more, but this will be ignored.
594 * @param blob FDT blob
595 * @param node node to examine
596 * @param prop_name name of property to find
597 * @param array array to fill with data
598 * @param count number of array elements
599 * @return number of array elements if ok, or -FDT_ERR_NOTFOUND if the
600 * property is not found
602 int fdtdec_get_int_array_count(const void *blob, int node,
603 const char *prop_name, u32 *array, int count);
606 * Look up a property in a node and return a pointer to its contents as a
607 * unsigned int array of given length. The property must have at least enough
608 * data for the array ('count' cells). It may have more, but this will be
609 * ignored. The data is not copied.
611 * Note that you must access elements of the array with fdt32_to_cpu(),
612 * since the elements will be big endian even on a little endian machine.
614 * @param blob FDT blob
615 * @param node node to examine
616 * @param prop_name name of property to find
617 * @param count number of array elements
618 * @return pointer to array if found, or NULL if the property is not
619 * found or there is not enough data
621 const u32 *fdtdec_locate_array(const void *blob, int node,
622 const char *prop_name, int count);
625 * Look up a boolean property in a node and return it.
627 * A boolean properly is true if present in the device tree and false if not
628 * present, regardless of its value.
630 * @param blob FDT blob
631 * @param node node to examine
632 * @param prop_name name of property to find
633 * @return 1 if the properly is present; 0 if it isn't present
635 int fdtdec_get_bool(const void *blob, int node, const char *prop_name);
638 * Look in the FDT for a config item with the given name and return its value
639 * as a 32-bit integer. The property must have at least 4 bytes of data. The
640 * value of the first cell is returned.
642 * @param blob FDT blob to use
643 * @param prop_name Node property name
644 * @param default_val default value to return if the property is not found
645 * @return integer value, if found, or default_val if not
647 int fdtdec_get_config_int(const void *blob, const char *prop_name,
651 * Look in the FDT for a config item with the given name
652 * and return whether it exists.
654 * @param blob FDT blob
655 * @param prop_name property name to look up
656 * @return 1, if it exists, or 0 if not
658 int fdtdec_get_config_bool(const void *blob, const char *prop_name);
661 * Look in the FDT for a config item with the given name and return its value
664 * @param blob FDT blob
665 * @param prop_name property name to look up
666 * @returns property string, NULL on error.
668 char *fdtdec_get_config_string(const void *blob, const char *prop_name);
671 * Look up a property in a node and return its contents in a byte
672 * array of given length. The property must have at least enough data for
673 * the array (count bytes). It may have more, but this will be ignored.
675 * @param blob FDT blob
676 * @param node node to examine
677 * @param prop_name name of property to find
678 * @param array array to fill with data
679 * @param count number of array elements
680 * @return 0 if ok, or -FDT_ERR_MISSING if the property is not found,
681 * or -FDT_ERR_BADLAYOUT if not enough data
683 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
684 u8 *array, int count);
687 * Look up a property in a node and return a pointer to its contents as a
688 * byte array of given length. The property must have at least enough data
689 * for the array (count bytes). It may have more, but this will be ignored.
690 * The data is not copied.
692 * @param blob FDT blob
693 * @param node node to examine
694 * @param prop_name name of property to find
695 * @param count number of array elements
696 * @return pointer to byte array if found, or NULL if the property is not
697 * found or there is not enough data
699 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
700 const char *prop_name, int count);
703 * Look up a property in a node which contains a memory region address and
704 * size. Then return a pointer to this address.
706 * The property must hold one address with a length. This is only tested on
709 * @param blob FDT blob
710 * @param node node to examine
711 * @param prop_name name of property to find
712 * @param basep Returns base address of region
713 * @param size Returns size of region
714 * @return 0 if ok, -1 on error (property not found)
716 int fdtdec_decode_region(const void *blob, int node, const char *prop_name,
717 fdt_addr_t *basep, fdt_size_t *sizep);
719 enum fmap_compress_t {
730 /* A flash map entry, containing an offset and length */
734 uint32_t used; /* Number of bytes used in region */
735 enum fmap_compress_t compress_algo; /* Compression type */
736 enum fmap_hash_t hash_algo; /* Hash algorithm */
737 const uint8_t *hash; /* Hash value */
738 int hash_size; /* Hash size */
742 * Read a flash entry from the fdt
744 * @param blob FDT blob
745 * @param node Offset of node to read
746 * @param name Name of node being read
747 * @param entry Place to put offset and size of this node
748 * @return 0 if ok, -ve on error
750 int fdtdec_read_fmap_entry(const void *blob, int node, const char *name,
751 struct fmap_entry *entry);
754 * Obtain an indexed resource from a device property.
756 * @param fdt FDT blob
757 * @param node node to examine
758 * @param property name of the property to parse
759 * @param index index of the resource to retrieve
760 * @param res returns the resource
761 * @return 0 if ok, negative on error
763 int fdt_get_resource(const void *fdt, int node, const char *property,
764 unsigned int index, struct fdt_resource *res);
767 * Obtain a named resource from a device property.
769 * Look up the index of the name in a list of strings and return the resource
772 * @param fdt FDT blob
773 * @param node node to examine
774 * @param property name of the property to parse
775 * @param prop_names name of the property containing the list of names
776 * @param name the name of the entry to look up
777 * @param res returns the resource
779 int fdt_get_named_resource(const void *fdt, int node, const char *property,
780 const char *prop_names, const char *name,
781 struct fdt_resource *res);
784 * Decode a named region within a memory bank of a given type.
786 * This function handles selection of a memory region. The region is
787 * specified as an offset/size within a particular type of memory.
789 * The properties used are:
791 * <mem_type>-memory<suffix> for the name of the memory bank
792 * <mem_type>-offset<suffix> for the offset in that bank
794 * The property value must have an offset and a size. The function checks
795 * that the region is entirely within the memory bank.5
797 * @param blob FDT blob
798 * @param node Node containing the properties (-1 for /config)
799 * @param mem_type Type of memory to use, which is a name, such as
800 * "u-boot" or "kernel".
801 * @param suffix String to append to the memory/offset
803 * @param basep Returns base of region
804 * @param sizep Returns size of region
805 * @return 0 if OK, -ive on error
807 int fdtdec_decode_memory_region(const void *blob, int node,
808 const char *mem_type, const char *suffix,
809 fdt_addr_t *basep, fdt_size_t *sizep);
811 /* Display timings from linux include/video/display_timing.h */
813 DISPLAY_FLAGS_HSYNC_LOW = 1 << 0,
814 DISPLAY_FLAGS_HSYNC_HIGH = 1 << 1,
815 DISPLAY_FLAGS_VSYNC_LOW = 1 << 2,
816 DISPLAY_FLAGS_VSYNC_HIGH = 1 << 3,
818 /* data enable flag */
819 DISPLAY_FLAGS_DE_LOW = 1 << 4,
820 DISPLAY_FLAGS_DE_HIGH = 1 << 5,
821 /* drive data on pos. edge */
822 DISPLAY_FLAGS_PIXDATA_POSEDGE = 1 << 6,
823 /* drive data on neg. edge */
824 DISPLAY_FLAGS_PIXDATA_NEGEDGE = 1 << 7,
825 DISPLAY_FLAGS_INTERLACED = 1 << 8,
826 DISPLAY_FLAGS_DOUBLESCAN = 1 << 9,
827 DISPLAY_FLAGS_DOUBLECLK = 1 << 10,
831 * A single signal can be specified via a range of minimal and maximal values
832 * with a typical value, that lies somewhere inbetween.
834 struct timing_entry {
841 * Single "mode" entry. This describes one set of signal timings a display can
842 * have in one setting. This struct can later be converted to struct videomode
843 * (see include/video/videomode.h). As each timing_entry can be defined as a
844 * range, one struct display_timing may become multiple struct videomodes.
846 * Example: hsync active high, vsync active low
849 * Video ______________________XXXXXXXXXXXXXXXXXXXXXX_____________________
850 * |<- sync ->|<- back ->|<----- active ----->|<- front ->|<- sync..
851 * | | porch | | porch |
853 * HSync _|¯¯¯¯¯¯¯¯¯¯|___________________________________________|¯¯¯¯¯¯¯¯¯
855 * VSync ¯|__________|¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯|_________
857 struct display_timing {
858 struct timing_entry pixelclock;
860 struct timing_entry hactive; /* hor. active video */
861 struct timing_entry hfront_porch; /* hor. front porch */
862 struct timing_entry hback_porch; /* hor. back porch */
863 struct timing_entry hsync_len; /* hor. sync len */
865 struct timing_entry vactive; /* ver. active video */
866 struct timing_entry vfront_porch; /* ver. front porch */
867 struct timing_entry vback_porch; /* ver. back porch */
868 struct timing_entry vsync_len; /* ver. sync len */
870 enum display_flags flags; /* display flags */
874 * fdtdec_decode_display_timing() - decode display timings
876 * Decode display timings from the supplied 'display-timings' node.
877 * See doc/device-tree-bindings/video/display-timing.txt for binding
880 * @param blob FDT blob
881 * @param node 'display-timing' node containing the timing subnodes
882 * @param index Index number to read (0=first timing subnode)
883 * @param config Place to put timings
884 * @return 0 if OK, -FDT_ERR_NOTFOUND if not found
886 int fdtdec_decode_display_timing(const void *blob, int node, int index,
887 struct display_timing *config);
889 * Set up the device tree ready for use
891 int fdtdec_setup(void);