1 /* SPDX-License-Identifier: GPL-2.0+ */
3 * Copyright (c) 2011 The Chromium OS Authors.
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.
17 #include <linux/libfdt.h>
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;
27 #define FDT_SIZE_T_NONE (-1U)
29 #ifdef CONFIG_PHYS_64BIT
30 #define FDT_ADDR_T_NONE ((ulong)(-1))
32 #define fdt_addr_to_cpu(reg) be64_to_cpu(reg)
33 #define fdt_size_to_cpu(reg) be64_to_cpu(reg)
34 #define cpu_to_fdt_addr(reg) cpu_to_be64(reg)
35 #define cpu_to_fdt_size(reg) cpu_to_be64(reg)
36 typedef fdt64_t fdt_val_t;
38 #define FDT_ADDR_T_NONE (-1U)
40 #define fdt_addr_to_cpu(reg) be32_to_cpu(reg)
41 #define fdt_size_to_cpu(reg) be32_to_cpu(reg)
42 #define cpu_to_fdt_addr(reg) cpu_to_be32(reg)
43 #define cpu_to_fdt_size(reg) cpu_to_be32(reg)
44 typedef fdt32_t fdt_val_t;
47 /* Information obtained about memory from the FDT */
56 * enum fdt_source_t - indicates where the devicetree came from
58 * These are listed in approximate order of desirability after FDTSRC_NONE
60 * @FDTSRC_SEPARATE: Appended to U-Boot. This is the normal approach if U-Boot
61 * is the only firmware being booted
62 * @FDTSRC_FIT: Found in a multi-dtb FIT. This should be used when U-Boot must
63 * select a devicetree from many options
64 * @FDTSRC_BOARD: Located by custom board code. This should only be used when
65 * the prior stage does not support FDTSRC_PASSAGE
66 * @FDTSRC_EMBED: Embedded into U-Boot executable. This should onyl be used when
67 * U-Boot is packaged as an ELF file, e.g. for debugging purposes
68 * @FDTSRC_ENV: Provided by the fdtcontroladdr environment variable. This should
69 * be used for debugging/development only
70 * @FDTSRC_NONE: No devicetree at all
81 * Information about a resource. start is the first address of the resource
82 * and end is the last address (inclusive). The length of the resource will
83 * be equal to: end - start + 1.
91 FDT_PCI_SPACE_CONFIG = 0,
92 FDT_PCI_SPACE_IO = 0x01000000,
93 FDT_PCI_SPACE_MEM32 = 0x02000000,
94 FDT_PCI_SPACE_MEM64 = 0x03000000,
95 FDT_PCI_SPACE_MEM32_PREF = 0x42000000,
96 FDT_PCI_SPACE_MEM64_PREF = 0x43000000,
99 #define FDT_PCI_ADDR_CELLS 3
100 #define FDT_PCI_SIZE_CELLS 2
101 #define FDT_PCI_REG_SIZE \
102 ((FDT_PCI_ADDR_CELLS + FDT_PCI_SIZE_CELLS) * sizeof(u32))
105 * The Open Firmware spec defines PCI physical address as follows:
107 * bits# 31 .... 24 23 .... 16 15 .... 08 07 .... 00
109 * phys.hi cell: npt000ss bbbbbbbb dddddfff rrrrrrrr
110 * phys.mid cell: hhhhhhhh hhhhhhhh hhhhhhhh hhhhhhhh
111 * phys.lo cell: llllllll llllllll llllllll llllllll
115 * n: is 0 if the address is relocatable, 1 otherwise
116 * p: is 1 if addressable region is prefetchable, 0 otherwise
117 * t: is 1 if the address is aliased (for non-relocatable I/O) below 1MB
118 * (for Memory), or below 64KB (for relocatable I/O)
119 * ss: is the space code, denoting the address space
120 * bbbbbbbb: is the 8-bit Bus Number
121 * ddddd: is the 5-bit Device Number
122 * fff: is the 3-bit Function Number
123 * rrrrrrrr: is the 8-bit Register Number
124 * hhhhhhhh: is a 32-bit unsigned number
125 * llllllll: is a 32-bit unsigned number
127 struct fdt_pci_addr {
133 extern u8 __dtb_dt_begin[]; /* embedded device tree blob */
134 extern u8 __dtb_dt_spl_begin[]; /* embedded device tree blob for SPL/TPL */
136 /* Get a pointer to the embedded devicetree, if there is one, else NULL */
137 static inline u8 *dtb_dt_embedded(void)
139 #ifdef CONFIG_OF_EMBED
140 # ifdef CONFIG_SPL_BUILD
141 return __dtb_dt_spl_begin;
143 return __dtb_dt_begin;
151 * Compute the size of a resource.
153 * @param res the resource to operate on
154 * Return: the size of the resource
156 static inline fdt_size_t fdt_resource_size(const struct fdt_resource *res)
158 return res->end - res->start + 1;
162 * Compat types that we know about and for which we might have drivers.
163 * Each is named COMPAT_<dir>_<filename> where <dir> is the directory
168 COMPAT_NVIDIA_TEGRA20_EMC, /* Tegra20 memory controller */
169 COMPAT_NVIDIA_TEGRA20_EMC_TABLE, /* Tegra20 memory timing table */
170 COMPAT_NVIDIA_TEGRA20_NAND, /* Tegra2 NAND controller */
171 COMPAT_NVIDIA_TEGRA124_XUSB_PADCTL,
172 /* Tegra124 XUSB pad controller */
173 COMPAT_NVIDIA_TEGRA210_XUSB_PADCTL,
174 /* Tegra210 XUSB pad controller */
175 COMPAT_SAMSUNG_EXYNOS_USB_PHY, /* Exynos phy controller for usb2.0 */
176 COMPAT_SAMSUNG_EXYNOS5_USB3_PHY,/* Exynos phy controller for usb3.0 */
177 COMPAT_SAMSUNG_EXYNOS_TMU, /* Exynos TMU */
178 COMPAT_SAMSUNG_EXYNOS_MIPI_DSI, /* Exynos mipi dsi */
179 COMPAT_SAMSUNG_EXYNOS_DWMMC, /* Exynos DWMMC controller */
180 COMPAT_GENERIC_SPI_FLASH, /* Generic SPI Flash chip */
181 COMPAT_SAMSUNG_EXYNOS_SYSMMU, /* Exynos sysmmu */
182 COMPAT_INTEL_MICROCODE, /* Intel microcode update */
183 COMPAT_INTEL_QRK_MRC, /* Intel Quark MRC */
184 COMPAT_ALTERA_SOCFPGA_DWMAC, /* SoCFPGA Ethernet controller */
185 COMPAT_ALTERA_SOCFPGA_DWMMC, /* SoCFPGA DWMMC controller */
186 COMPAT_ALTERA_SOCFPGA_DWC2USB, /* SoCFPGA DWC2 USB controller */
187 COMPAT_INTEL_BAYTRAIL_FSP, /* Intel Bay Trail FSP */
188 COMPAT_INTEL_BAYTRAIL_FSP_MDP, /* Intel FSP memory-down params */
189 COMPAT_INTEL_IVYBRIDGE_FSP, /* Intel Ivy Bridge FSP */
190 COMPAT_SUNXI_NAND, /* SUNXI NAND controller */
191 COMPAT_ALTERA_SOCFPGA_CLK, /* SoCFPGA Clock initialization */
192 COMPAT_ALTERA_SOCFPGA_PINCTRL_SINGLE, /* SoCFPGA pinctrl-single */
193 COMPAT_ALTERA_SOCFPGA_H2F_BRG, /* SoCFPGA hps2fpga bridge */
194 COMPAT_ALTERA_SOCFPGA_LWH2F_BRG, /* SoCFPGA lwhps2fpga bridge */
195 COMPAT_ALTERA_SOCFPGA_F2H_BRG, /* SoCFPGA fpga2hps bridge */
196 COMPAT_ALTERA_SOCFPGA_F2SDR0, /* SoCFPGA fpga2SDRAM0 bridge */
197 COMPAT_ALTERA_SOCFPGA_F2SDR1, /* SoCFPGA fpga2SDRAM1 bridge */
198 COMPAT_ALTERA_SOCFPGA_F2SDR2, /* SoCFPGA fpga2SDRAM2 bridge */
199 COMPAT_ALTERA_SOCFPGA_FPGA0, /* SOCFPGA FPGA manager */
200 COMPAT_ALTERA_SOCFPGA_NOC, /* SOCFPGA Arria 10 NOC */
201 COMPAT_ALTERA_SOCFPGA_CLK_INIT, /* SOCFPGA Arria 10 clk init */
206 #define MAX_PHANDLE_ARGS 16
207 struct fdtdec_phandle_args {
210 uint32_t args[MAX_PHANDLE_ARGS];
214 * fdtdec_parse_phandle_with_args() - Find a node pointed by phandle in a list
216 * This function is useful to parse lists of phandles and their arguments.
229 * list = <&phandle1 1 2 &phandle2 3>;
232 * To get a device_node of the `node2' node you may call this:
233 * fdtdec_parse_phandle_with_args(blob, node3, "list", "#list-cells", 0, 1,
236 * (This function is a modified version of __of_parse_phandle_with_args() from
239 * @blob: Pointer to device tree
240 * @src_node: Offset of device tree node containing a list
241 * @list_name: property name that contains a list
242 * @cells_name: property name that specifies the phandles' arguments count,
243 * or NULL to use @cells_count
244 * @cells_count: Cell count to use if @cells_name is NULL
245 * @index: index of a phandle to parse out
246 * @out_args: optional pointer to output arguments structure (will be filled)
247 * Return: 0 on success (with @out_args filled out if not NULL), -ENOENT if
248 * @list_name does not exist, a phandle was not found, @cells_name
249 * could not be found, the arguments were truncated or there were too
253 int fdtdec_parse_phandle_with_args(const void *blob, int src_node,
254 const char *list_name,
255 const char *cells_name,
256 int cell_count, int index,
257 struct fdtdec_phandle_args *out_args);
260 * Find the next numbered alias for a peripheral. This is used to enumerate
261 * all the peripherals of a certain type.
263 * Do the first call with *upto = 0. Assuming /aliases/<name>0 exists then
264 * this function will return a pointer to the node the alias points to, and
265 * then update *upto to 1. Next time you call this function, the next node
268 * All nodes returned will match the compatible ID, as it is assumed that
269 * all peripherals use the same driver.
271 * @param blob FDT blob to use
272 * @param name Root name of alias to search for
273 * @param id Compatible ID to look for
274 * Return: offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
276 int fdtdec_next_alias(const void *blob, const char *name,
277 enum fdt_compat_id id, int *upto);
280 * Find the compatible ID for a given node.
282 * Generally each node has at least one compatible string attached to it.
283 * This function looks through our list of known compatible strings and
284 * returns the corresponding ID which matches the compatible string.
286 * @param blob FDT blob to use
287 * @param node Node containing compatible string to find
288 * Return: compatible ID, or COMPAT_UNKNOWN if we cannot find a match
290 enum fdt_compat_id fdtdec_lookup(const void *blob, int node);
293 * Find the next compatible node for a peripheral.
295 * Do the first call with node = 0. This function will return a pointer to
296 * the next compatible node. Next time you call this function, pass the
297 * value returned, and the next node will be provided.
299 * @param blob FDT blob to use
300 * @param node Start node for search
301 * @param id Compatible ID to look for (enum fdt_compat_id)
302 * Return: offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
304 int fdtdec_next_compatible(const void *blob, int node,
305 enum fdt_compat_id id);
308 * Find the next compatible subnode for a peripheral.
310 * Do the first call with node set to the parent and depth = 0. This
311 * function will return the offset of the next compatible node. Next time
312 * you call this function, pass the node value returned last time, with
313 * depth unchanged, and the next node will be provided.
315 * @param blob FDT blob to use
316 * @param node Start node for search
317 * @param id Compatible ID to look for (enum fdt_compat_id)
318 * @param depthp Current depth (set to 0 before first call)
319 * Return: offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
321 int fdtdec_next_compatible_subnode(const void *blob, int node,
322 enum fdt_compat_id id, int *depthp);
325 * Look up an address property in a node and return the parsed address, and
326 * optionally the parsed size.
328 * This variant assumes a known and fixed number of cells are used to
329 * represent the address and size.
331 * You probably don't want to use this function directly except to parse
332 * non-standard properties, and never to parse the "reg" property. Instead,
333 * use one of the "auto" variants below, which automatically honor the
334 * #address-cells and #size-cells properties in the parent node.
336 * @param blob FDT blob
337 * @param node node to examine
338 * @param prop_name name of property to find
339 * @param index which address to retrieve from a list of addresses. Often 0.
340 * @param na the number of cells used to represent an address
341 * @param ns the number of cells used to represent a size
342 * @param sizep a pointer to store the size into. Use NULL if not required
343 * @param translate Indicates whether to translate the returned value
344 * using the parent node's ranges property.
345 * Return: address, if found, or FDT_ADDR_T_NONE if not
347 fdt_addr_t fdtdec_get_addr_size_fixed(const void *blob, int node,
348 const char *prop_name, int index, int na, int ns,
349 fdt_size_t *sizep, bool translate);
352 * Look up an address property in a node and return the parsed address, and
353 * optionally the parsed size.
355 * This variant automatically determines the number of cells used to represent
356 * the address and size by parsing the provided parent node's #address-cells
357 * and #size-cells properties.
359 * @param blob FDT blob
360 * @param parent parent node of @node
361 * @param node node to examine
362 * @param prop_name name of property to find
363 * @param index which address to retrieve from a list of addresses. Often 0.
364 * @param sizep a pointer to store the size into. Use NULL if not required
365 * @param translate Indicates whether to translate the returned value
366 * using the parent node's ranges property.
367 * Return: address, if found, or FDT_ADDR_T_NONE if not
369 fdt_addr_t fdtdec_get_addr_size_auto_parent(const void *blob, int parent,
370 int node, const char *prop_name, int index, fdt_size_t *sizep,
374 * Look up an address property in a node and return the parsed address, and
375 * optionally the parsed size.
377 * This variant automatically determines the number of cells used to represent
378 * the address and size by parsing the parent node's #address-cells
379 * and #size-cells properties. The parent node is automatically found.
381 * The automatic parent lookup implemented by this function is slow.
382 * Consequently, fdtdec_get_addr_size_auto_parent() should be used where
385 * @param blob FDT blob
386 * @param parent parent node of @node
387 * @param node node to examine
388 * @param prop_name name of property to find
389 * @param index which address to retrieve from a list of addresses. Often 0.
390 * @param sizep a pointer to store the size into. Use NULL if not required
391 * @param translate Indicates whether to translate the returned value
392 * using the parent node's ranges property.
393 * Return: address, if found, or FDT_ADDR_T_NONE if not
395 fdt_addr_t fdtdec_get_addr_size_auto_noparent(const void *blob, int node,
396 const char *prop_name, int index, fdt_size_t *sizep,
400 * Look up an address property in a node and return the parsed address.
402 * This variant hard-codes the number of cells used to represent the address
403 * and size based on sizeof(fdt_addr_t) and sizeof(fdt_size_t). It also
404 * always returns the first address value in the property (index 0).
406 * Use of this function is not recommended due to the hard-coding of cell
407 * counts. There is no programmatic validation that these hard-coded values
408 * actually match the device tree content in any way at all. This assumption
409 * can be satisfied by manually ensuring CONFIG_PHYS_64BIT is appropriately
410 * set in the U-Boot build and exercising strict control over DT content to
411 * ensure use of matching #address-cells/#size-cells properties. However, this
412 * approach is error-prone; those familiar with DT will not expect the
413 * assumption to exist, and could easily invalidate it. If the assumption is
414 * invalidated, this function will not report the issue, and debugging will
415 * be required. Instead, use fdtdec_get_addr_size_auto_parent().
417 * @param blob FDT blob
418 * @param node node to examine
419 * @param prop_name name of property to find
420 * Return: address, if found, or FDT_ADDR_T_NONE if not
422 fdt_addr_t fdtdec_get_addr(const void *blob, int node,
423 const char *prop_name);
426 * Look up an address property in a node and return the parsed address, and
427 * optionally the parsed size.
429 * This variant hard-codes the number of cells used to represent the address
430 * and size based on sizeof(fdt_addr_t) and sizeof(fdt_size_t). It also
431 * always returns the first address value in the property (index 0).
433 * Use of this function is not recommended due to the hard-coding of cell
434 * counts. There is no programmatic validation that these hard-coded values
435 * actually match the device tree content in any way at all. This assumption
436 * can be satisfied by manually ensuring CONFIG_PHYS_64BIT is appropriately
437 * set in the U-Boot build and exercising strict control over DT content to
438 * ensure use of matching #address-cells/#size-cells properties. However, this
439 * approach is error-prone; those familiar with DT will not expect the
440 * assumption to exist, and could easily invalidate it. If the assumption is
441 * invalidated, this function will not report the issue, and debugging will
442 * be required. Instead, use fdtdec_get_addr_size_auto_parent().
444 * @param blob FDT blob
445 * @param node node to examine
446 * @param prop_name name of property to find
447 * @param sizep a pointer to store the size into. Use NULL if not required
448 * Return: address, if found, or FDT_ADDR_T_NONE if not
450 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
451 const char *prop_name, fdt_size_t *sizep);
454 * Look at the compatible property of a device node that represents a PCI
455 * device and extract pci vendor id and device id from it.
457 * @param blob FDT blob
458 * @param node node to examine
459 * @param vendor vendor id of the pci device
460 * @param device device id of the pci device
461 * Return: 0 if ok, negative on error
463 int fdtdec_get_pci_vendev(const void *blob, int node,
464 u16 *vendor, u16 *device);
467 * Look at the pci address of a device node that represents a PCI device
468 * and return base address of the pci device's registers.
470 * @param dev device to examine
471 * @param addr pci address in the form of fdt_pci_addr
472 * @param bar returns base address of the pci device's registers
473 * Return: 0 if ok, negative on error
475 int fdtdec_get_pci_bar32(const struct udevice *dev, struct fdt_pci_addr *addr,
479 * Look at the bus range property of a device node and return the pci bus
480 * range for this node.
481 * The property must hold one fdt_pci_addr with a length.
482 * @param blob FDT blob
483 * @param node node to examine
484 * @param res the resource structure to return the bus range
485 * Return: 0 if ok, negative on error
488 int fdtdec_get_pci_bus_range(const void *blob, int node,
489 struct fdt_resource *res);
492 * Look up a 32-bit integer property in a node and return it. The property
493 * must have at least 4 bytes of data. The value of the first cell is
496 * @param blob FDT blob
497 * @param node node to examine
498 * @param prop_name name of property to find
499 * @param default_val default value to return if the property is not found
500 * Return: integer value, if found, or default_val if not
502 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
506 * Unsigned version of fdtdec_get_int. The property must have at least
507 * 4 bytes of data. The value of the first cell is returned.
509 * @param blob FDT blob
510 * @param node node to examine
511 * @param prop_name name of property to find
512 * @param default_val default value to return if the property is not found
513 * Return: unsigned integer value, if found, or default_val if not
515 unsigned int fdtdec_get_uint(const void *blob, int node, const char *prop_name,
516 unsigned int default_val);
519 * Get a variable-sized number from a property
521 * This reads a number from one or more cells.
523 * @param ptr Pointer to property
524 * @param cells Number of cells containing the number
525 * Return: the value in the cells
527 u64 fdtdec_get_number(const fdt32_t *ptr, unsigned int cells);
530 * Look up a 64-bit integer property in a node and return it. The property
531 * must have at least 8 bytes of data (2 cells). The first two cells are
532 * concatenated to form a 8 bytes value, where the first cell is top half and
533 * the second cell is bottom half.
535 * @param blob FDT blob
536 * @param node node to examine
537 * @param prop_name name of property to find
538 * @param default_val default value to return if the property is not found
539 * Return: integer value, if found, or default_val if not
541 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
542 uint64_t default_val);
545 * Checks whether a node is enabled.
546 * This looks for a 'status' property. If this exists, then returns 1 if
547 * the status is 'ok' and 0 otherwise. If there is no status property,
548 * it returns 1 on the assumption that anything mentioned should be enabled
551 * @param blob FDT blob
552 * @param node node to examine
553 * Return: integer value 0 (not enabled) or 1 (enabled)
555 int fdtdec_get_is_enabled(const void *blob, int node);
558 * Checks that we have a valid fdt available to control U-Boot.
560 * However, if not then for the moment nothing is done, since this function
561 * is called too early to panic().
565 int fdtdec_check_fdt(void);
568 * Find the nodes for a peripheral and return a list of them in the correct
569 * order. This is used to enumerate all the peripherals of a certain type.
571 * To use this, optionally set up a /aliases node with alias properties for
572 * a peripheral. For example, for usb you could have:
575 * usb0 = "/ehci@c5008000";
576 * usb1 = "/ehci@c5000000";
579 * Pass "usb" as the name to this function and will return a list of two
580 * nodes offsets: /ehci@c5008000 and ehci@c5000000.
582 * All nodes returned will match the compatible ID, as it is assumed that
583 * all peripherals use the same driver.
585 * If no alias node is found, then the node list will be returned in the
586 * order found in the fdt. If the aliases mention a node which doesn't
587 * exist, then this will be ignored. If nodes are found with no aliases,
588 * they will be added in any order.
590 * If there is a gap in the aliases, then this function return a 0 node at
591 * that position. The return value will also count these gaps.
593 * This function checks node properties and will not return nodes which are
594 * marked disabled (status = "disabled").
596 * @param blob FDT blob to use
597 * @param name Root name of alias to search for
598 * @param id Compatible ID to look for
599 * @param node_list Place to put list of found nodes
600 * @param maxcount Maximum number of nodes to find
601 * Return: number of nodes found on success, FDT_ERR_... on error
603 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
604 enum fdt_compat_id id, int *node_list, int maxcount);
607 * This function is similar to fdtdec_find_aliases_for_id() except that it
608 * adds to the node_list that is passed in. Any 0 elements are considered
609 * available for allocation - others are considered already used and are
612 * You can use this by calling fdtdec_find_aliases_for_id() with an
613 * uninitialised array, then setting the elements that are returned to -1,
614 * say, then calling this function, perhaps with a different compat id.
615 * Any elements you get back that are >0 are new nodes added by the call
618 * Note that if you have some nodes with aliases and some without, you are
619 * sailing close to the wind. The call to fdtdec_find_aliases_for_id() with
620 * one compat_id may fill in positions for which you have aliases defined
621 * for another compat_id. When you later call *this* function with the second
622 * compat_id, the alias positions may already be used. A debug warning may
623 * be generated in this case, but it is safest to define aliases for all
624 * nodes when you care about the ordering.
626 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
627 enum fdt_compat_id id, int *node_list, int maxcount);
630 * Get the alias sequence number of a node
632 * This works out whether a node is pointed to by an alias, and if so, the
633 * sequence number of that alias. Aliases are of the form <base><num> where
634 * <num> is the sequence number. For example spi2 would be sequence number
637 * @param blob Device tree blob (if NULL, then error is returned)
638 * @param base Base name for alias (before the underscore)
639 * @param node Node to look up
640 * @param seqp This is set to the sequence number if one is found,
641 * but otherwise the value is left alone
642 * Return: 0 if a sequence was found, -ve if not
644 int fdtdec_get_alias_seq(const void *blob, const char *base, int node,
648 * Get the highest alias number for susbystem.
650 * It parses all aliases and find out highest recorded alias for subsystem.
651 * Aliases are of the form <base><num> where <num> is the sequence number.
653 * @param blob Device tree blob (if NULL, then error is returned)
654 * @param base Base name for alias susbystem (before the number)
656 * Return: 0 highest alias ID, -1 if not found
658 int fdtdec_get_alias_highest_id(const void *blob, const char *base);
661 * Get a property from the /chosen node
663 * @param blob Device tree blob (if NULL, then NULL is returned)
664 * @param name Property name to look up
665 * Return: Value of property, or NULL if it does not exist
667 const char *fdtdec_get_chosen_prop(const void *blob, const char *name);
670 * Get the offset of the given /chosen node
672 * This looks up a property in /chosen containing the path to another node,
673 * then finds the offset of that node.
675 * @param blob Device tree blob (if NULL, then error is returned)
676 * @param name Property name, e.g. "stdout-path"
677 * Return: Node offset referred to by that chosen node, or -ve FDT_ERR_...
679 int fdtdec_get_chosen_node(const void *blob, const char *name);
682 * Get the name for a compatible ID
684 * @param id Compatible ID to look for
685 * Return: compatible string for that id
687 const char *fdtdec_get_compatible(enum fdt_compat_id id);
689 /* Look up a phandle and follow it to its node. Then return the offset
692 * @param blob FDT blob
693 * @param node node to examine
694 * @param prop_name name of property to find
695 * Return: node offset if found, -ve error code on error
697 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name);
700 * Look up a property in a node and return its contents in an integer
701 * array of given length. The property must have at least enough data for
702 * the array (4*count bytes). It may have more, but this will be ignored.
704 * @param blob FDT blob
705 * @param node node to examine
706 * @param prop_name name of property to find
707 * @param array array to fill with data
708 * @param count number of array elements
709 * Return: 0 if ok, or -FDT_ERR_NOTFOUND if the property is not found,
710 * or -FDT_ERR_BADLAYOUT if not enough data
712 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
713 u32 *array, int count);
716 * Look up a property in a node and return its contents in an integer
717 * array of given length. The property must exist but may have less data that
718 * expected (4*count bytes). It may have more, but this will be ignored.
720 * @param blob FDT blob
721 * @param node node to examine
722 * @param prop_name name of property to find
723 * @param array array to fill with data
724 * @param count number of array elements
725 * Return: number of array elements if ok, or -FDT_ERR_NOTFOUND if the
726 * property is not found
728 int fdtdec_get_int_array_count(const void *blob, int node,
729 const char *prop_name, u32 *array, int count);
732 * Look up a property in a node and return a pointer to its contents as a
733 * unsigned int array of given length. The property must have at least enough
734 * data for the array ('count' cells). It may have more, but this will be
735 * ignored. The data is not copied.
737 * Note that you must access elements of the array with fdt32_to_cpu(),
738 * since the elements will be big endian even on a little endian machine.
740 * @param blob FDT blob
741 * @param node node to examine
742 * @param prop_name name of property to find
743 * @param count number of array elements
744 * Return: pointer to array if found, or NULL if the property is not
745 * found or there is not enough data
747 const u32 *fdtdec_locate_array(const void *blob, int node,
748 const char *prop_name, int count);
751 * Look up a boolean property in a node and return it.
753 * A boolean properly is true if present in the device tree and false if not
754 * present, regardless of its value.
756 * @param blob FDT blob
757 * @param node node to examine
758 * @param prop_name name of property to find
759 * Return: 1 if the properly is present; 0 if it isn't present
761 int fdtdec_get_bool(const void *blob, int node, const char *prop_name);
764 * Count child nodes of one parent node.
766 * @param blob FDT blob
767 * @param node parent node
768 * Return: number of child node; 0 if there is not child node
770 int fdtdec_get_child_count(const void *blob, int node);
773 * Look up a property in a node and return its contents in a byte
774 * array of given length. The property must have at least enough data for
775 * the array (count bytes). It may have more, but this will be ignored.
777 * @param blob FDT blob
778 * @param node node to examine
779 * @param prop_name name of property to find
780 * @param array array to fill with data
781 * @param count number of array elements
782 * Return: 0 if ok, or -FDT_ERR_MISSING if the property is not found,
783 * or -FDT_ERR_BADLAYOUT if not enough data
785 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
786 u8 *array, int count);
789 * Look up a property in a node and return a pointer to its contents as a
790 * byte array of given length. The property must have at least enough data
791 * for the array (count bytes). It may have more, but this will be ignored.
792 * The data is not copied.
794 * @param blob FDT blob
795 * @param node node to examine
796 * @param prop_name name of property to find
797 * @param count number of array elements
798 * Return: pointer to byte array if found, or NULL if the property is not
799 * found or there is not enough data
801 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
802 const char *prop_name, int count);
805 * Obtain an indexed resource from a device property.
807 * @param fdt FDT blob
808 * @param node node to examine
809 * @param property name of the property to parse
810 * @param index index of the resource to retrieve
811 * @param res returns the resource
812 * Return: 0 if ok, negative on error
814 int fdt_get_resource(const void *fdt, int node, const char *property,
815 unsigned int index, struct fdt_resource *res);
818 * Obtain a named resource from a device property.
820 * Look up the index of the name in a list of strings and return the resource
823 * @param fdt FDT blob
824 * @param node node to examine
825 * @param property name of the property to parse
826 * @param prop_names name of the property containing the list of names
827 * @param name the name of the entry to look up
828 * @param res returns the resource
830 int fdt_get_named_resource(const void *fdt, int node, const char *property,
831 const char *prop_names, const char *name,
832 struct fdt_resource *res);
834 /* Display timings from linux include/video/display_timing.h */
836 DISPLAY_FLAGS_HSYNC_LOW = 1 << 0,
837 DISPLAY_FLAGS_HSYNC_HIGH = 1 << 1,
838 DISPLAY_FLAGS_VSYNC_LOW = 1 << 2,
839 DISPLAY_FLAGS_VSYNC_HIGH = 1 << 3,
841 /* data enable flag */
842 DISPLAY_FLAGS_DE_LOW = 1 << 4,
843 DISPLAY_FLAGS_DE_HIGH = 1 << 5,
844 /* drive data on pos. edge */
845 DISPLAY_FLAGS_PIXDATA_POSEDGE = 1 << 6,
846 /* drive data on neg. edge */
847 DISPLAY_FLAGS_PIXDATA_NEGEDGE = 1 << 7,
848 DISPLAY_FLAGS_INTERLACED = 1 << 8,
849 DISPLAY_FLAGS_DOUBLESCAN = 1 << 9,
850 DISPLAY_FLAGS_DOUBLECLK = 1 << 10,
854 * A single signal can be specified via a range of minimal and maximal values
855 * with a typical value, that lies somewhere inbetween.
857 struct timing_entry {
864 * Single "mode" entry. This describes one set of signal timings a display can
865 * have in one setting. This struct can later be converted to struct videomode
866 * (see include/video/videomode.h). As each timing_entry can be defined as a
867 * range, one struct display_timing may become multiple struct videomodes.
869 * Example: hsync active high, vsync active low
872 * Video ______________________XXXXXXXXXXXXXXXXXXXXXX_____________________
873 * |<- sync ->|<- back ->|<----- active ----->|<- front ->|<- sync..
874 * | | porch | | porch |
876 * HSync _|¯¯¯¯¯¯¯¯¯¯|___________________________________________|¯¯¯¯¯¯¯¯¯
878 * VSync ¯|__________|¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯|_________
880 struct display_timing {
881 struct timing_entry pixelclock;
883 struct timing_entry hactive; /* hor. active video */
884 struct timing_entry hfront_porch; /* hor. front porch */
885 struct timing_entry hback_porch; /* hor. back porch */
886 struct timing_entry hsync_len; /* hor. sync len */
888 struct timing_entry vactive; /* ver. active video */
889 struct timing_entry vfront_porch; /* ver. front porch */
890 struct timing_entry vback_porch; /* ver. back porch */
891 struct timing_entry vsync_len; /* ver. sync len */
893 enum display_flags flags; /* display flags */
894 bool hdmi_monitor; /* is hdmi monitor? */
898 * fdtdec_decode_display_timing() - decode display timings
900 * Decode display timings from the supplied 'display-timings' node.
901 * See doc/device-tree-bindings/video/display-timing.txt for binding
904 * @param blob FDT blob
905 * @param node 'display-timing' node containing the timing subnodes
906 * @param index Index number to read (0=first timing subnode)
907 * @param config Place to put timings
908 * Return: 0 if OK, -FDT_ERR_NOTFOUND if not found
910 int fdtdec_decode_display_timing(const void *blob, int node, int index,
911 struct display_timing *config);
914 * fdtdec_setup_mem_size_base() - decode and setup gd->ram_size and
917 * Decode the /memory 'reg' property to determine the size and start of the
918 * first memory bank, populate the global data with the size and start of the
919 * first bank of memory.
921 * This function should be called from a boards dram_init(). This helper
922 * function allows for boards to query the device tree for DRAM size and start
923 * address instead of hard coding the value in the case where the memory size
924 * and start address cannot be detected automatically.
926 * Return: 0 if OK, -EINVAL if the /memory node or reg property is missing or
929 int fdtdec_setup_mem_size_base(void);
932 * fdtdec_setup_mem_size_base_lowest() - decode and setup gd->ram_size and
933 * gd->ram_start by lowest available memory base
935 * Decode the /memory 'reg' property to determine the lowest start of the memory
936 * bank bank and populate the global data with it.
938 * This function should be called from a boards dram_init(). This helper
939 * function allows for boards to query the device tree for DRAM size and start
940 * address instead of hard coding the value in the case where the memory size
941 * and start address cannot be detected automatically.
943 * Return: 0 if OK, -EINVAL if the /memory node or reg property is missing or
946 int fdtdec_setup_mem_size_base_lowest(void);
949 * fdtdec_setup_memory_banksize() - decode and populate gd->bd->bi_dram
951 * Decode the /memory 'reg' property to determine the address and size of the
952 * memory banks. Use this data to populate the global data board info with the
953 * phys address and size of memory banks.
955 * This function should be called from a boards dram_init_banksize(). This
956 * helper function allows for boards to query the device tree for memory bank
957 * information instead of hard coding the information in cases where it cannot
958 * be detected automatically.
960 * Return: 0 if OK, -EINVAL if the /memory node or reg property is missing or
963 int fdtdec_setup_memory_banksize(void);
966 * fdtdec_set_ethernet_mac_address() - set MAC address for default interface
968 * Looks up the default interface via the "ethernet" alias (in the /aliases
969 * node) and stores the given MAC in its "local-mac-address" property. This
970 * is useful on platforms that store the MAC address in a custom location.
971 * Board code can call this in the late init stage to make sure that the
972 * interface device tree node has the right MAC address configured for the
973 * Ethernet uclass to pick it up.
975 * Typically the FDT passed into this function will be U-Boot's control DTB.
976 * Given that a lot of code may be holding offsets to various nodes in that
977 * tree, this code will only set the "local-mac-address" property in-place,
978 * which means that it needs to exist and have space for the 6-byte address.
979 * This ensures that the operation is non-destructive and does not invalidate
980 * offsets that other drivers may be using.
982 * @param fdt FDT blob
983 * @param mac buffer containing the MAC address to set
984 * @param size size of MAC address
985 * Return: 0 on success or a negative error code on failure
987 int fdtdec_set_ethernet_mac_address(void *fdt, const u8 *mac, size_t size);
990 * fdtdec_set_phandle() - sets the phandle of a given node
992 * @param blob FDT blob
993 * @param node offset in the FDT blob of the node whose phandle is to
995 * @param phandle phandle to set for the given node
996 * Return: 0 on success or a negative error code on failure
998 static inline int fdtdec_set_phandle(void *blob, int node, uint32_t phandle)
1000 return fdt_setprop_u32(blob, node, "phandle", phandle);
1003 /* add "no-map" property */
1004 #define FDTDEC_RESERVED_MEMORY_NO_MAP (1 << 0)
1007 * fdtdec_add_reserved_memory() - add or find a reserved-memory node
1009 * If a reserved-memory node already exists for the given carveout, a phandle
1010 * for that node will be returned. Otherwise a new node will be created and a
1011 * phandle corresponding to it will be returned.
1013 * See Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt
1014 * for details on how to use reserved memory regions.
1016 * As an example, consider the following code snippet:
1018 * struct fdt_memory fb = {
1019 * .start = 0x92cb3000,
1020 * .end = 0x934b2fff,
1024 * fdtdec_add_reserved_memory(fdt, "framebuffer", &fb, NULL, 0, &phandle,
1027 * This results in the following subnode being added to the top-level
1028 * /reserved-memory node:
1031 * #address-cells = <0x00000002>;
1032 * #size-cells = <0x00000002>;
1035 * framebuffer@92cb3000 {
1036 * reg = <0x00000000 0x92cb3000 0x00000000 0x00800000>;
1037 * phandle = <0x0000004d>;
1041 * If the top-level /reserved-memory node does not exist, it will be created.
1042 * The phandle returned from the function call can be used to reference this
1043 * reserved memory region from other nodes.
1045 * See fdtdec_set_carveout() for a more elaborate example.
1047 * @param blob FDT blob
1048 * @param basename base name of the node to create
1049 * @param carveout information about the carveout region
1050 * @param compatibles list of compatible strings for the carveout region
1051 * @param count number of compatible strings for the carveout region
1052 * @param phandlep return location for the phandle of the carveout region
1053 * can be NULL if no phandle should be added
1054 * @param flags bitmask of flags to set for the carveout region
1055 * Return: 0 on success or a negative error code on failure
1057 int fdtdec_add_reserved_memory(void *blob, const char *basename,
1058 const struct fdt_memory *carveout,
1059 const char **compatibles, unsigned int count,
1060 uint32_t *phandlep, unsigned long flags);
1063 * fdtdec_get_carveout() - reads a carveout from an FDT
1065 * Reads information about a carveout region from an FDT. The carveout is a
1066 * referenced by its phandle that is read from a given property in a given
1069 * @param blob FDT blob
1070 * @param node name of a node
1071 * @param prop_name name of the property in the given node that contains
1072 * the phandle for the carveout
1073 * @param index index of the phandle for which to read the carveout
1074 * @param carveout return location for the carveout information
1075 * @param name return location for the carveout name
1076 * @param compatiblesp return location for compatible strings
1077 * @param countp return location for the number of compatible strings
1078 * @param flags return location for the flags of the carveout
1079 * Return: 0 on success or a negative error code on failure
1081 int fdtdec_get_carveout(const void *blob, const char *node,
1082 const char *prop_name, unsigned int index,
1083 struct fdt_memory *carveout, const char **name,
1084 const char ***compatiblesp, unsigned int *countp,
1085 unsigned long *flags);
1088 * fdtdec_set_carveout() - sets a carveout region for a given node
1090 * Sets a carveout region for a given node. If a reserved-memory node already
1091 * exists for the carveout, the phandle for that node will be reused. If no
1092 * such node exists, a new one will be created and a phandle to it stored in
1093 * a specified property of the given node.
1095 * As an example, consider the following code snippet:
1097 * const char *node = "/host1x@50000000/dc@54240000";
1098 * struct fdt_memory fb = {
1099 * .start = 0x92cb3000,
1100 * .end = 0x934b2fff,
1103 * fdtdec_set_carveout(fdt, node, "memory-region", 0, "framebuffer", NULL,
1106 * dc@54200000 is a display controller and was set up by the bootloader to
1107 * scan out the framebuffer specified by "fb". This would cause the following
1108 * reserved memory region to be added:
1111 * #address-cells = <0x00000002>;
1112 * #size-cells = <0x00000002>;
1115 * framebuffer@92cb3000 {
1116 * reg = <0x00000000 0x92cb3000 0x00000000 0x00800000>;
1117 * phandle = <0x0000004d>;
1121 * A "memory-region" property will also be added to the node referenced by the
1129 * memory-region = <0x0000004d>;
1136 * @param blob FDT blob
1137 * @param node name of the node to add the carveout to
1138 * @param prop_name name of the property in which to store the phandle of
1140 * @param index index of the phandle to store
1141 * @param carveout information about the carveout to add
1142 * @param name base name of the reserved-memory node to create
1143 * @param compatibles compatible strings to set for the carveout
1144 * @param count number of compatible strings
1145 * @param flags bitmask of flags to set for the carveout
1146 * Return: 0 on success or a negative error code on failure
1148 int fdtdec_set_carveout(void *blob, const char *node, const char *prop_name,
1149 unsigned int index, const struct fdt_memory *carveout,
1150 const char *name, const char **compatibles,
1151 unsigned int count, unsigned long flags);
1154 * Set up the device tree ready for use
1156 int fdtdec_setup(void);
1159 * Perform board-specific early DT adjustments
1161 int fdtdec_board_setup(const void *fdt_blob);
1164 * fdtdec_resetup() - Set up the device tree again
1166 * The main difference with fdtdec_setup() is that it returns if the fdt has
1167 * changed because a better match has been found.
1168 * This is typically used for boards that rely on a DM driver to detect the
1169 * board type. This function sould be called by the board code after the stuff
1170 * needed by board_fit_config_name_match() to operate porperly is available.
1171 * If this functions signals that a rescan is necessary, the board code must
1172 * unbind all the drivers using dm_uninit() and then rescan the DT with
1173 * dm_init_and_scan().
1175 * @param rescan Returns a flag indicating that fdt has changed and rescanning
1176 * the fdt is required
1178 * Return: 0 if OK, -ve on error
1180 int fdtdec_resetup(int *rescan);
1183 * Board-specific FDT initialization. Returns the address to a device tree blob.
1185 * Called when CONFIG_OF_BOARD is defined.
1187 * The existing devicetree is available at gd->fdt_blob
1189 * @err internal error code if we fail to setup a DTB
1190 * @returns new devicetree blob pointer
1192 void *board_fdt_blob_setup(int *err);
1195 * Decode the size of memory
1197 * RAM size is normally set in a /memory node and consists of a list of
1198 * (base, size) cells in the 'reg' property. This information is used to
1199 * determine the total available memory as well as the address and size
1202 * Optionally the memory configuration can vary depending on a board id,
1203 * typically read from strapping resistors or an EEPROM on the board.
1205 * Finally, memory size can be detected (within certain limits) by probing
1206 * the available memory. It is safe to do so within the limits provides by
1207 * the board's device tree information. This makes it possible to produce
1208 * boards with different memory sizes, where the device tree specifies the
1209 * maximum memory configuration, and the smaller memory configuration is
1212 * This function decodes that information, returning the memory base address,
1213 * size and bank information. See the memory.txt binding for full
1216 * @param blob Device tree blob
1217 * @param area Name of node to check (NULL means "/memory")
1218 * @param board_id Board ID to look up
1219 * @param basep Returns base address of first memory bank (NULL to
1221 * @param sizep Returns total memory size (NULL to ignore)
1222 * @param bd Updated with the memory bank information (NULL to skip)
1223 * Return: 0 if OK, -ve on error
1225 int fdtdec_decode_ram_size(const void *blob, const char *area, int board_id,
1226 phys_addr_t *basep, phys_size_t *sizep,
1227 struct bd_info *bd);
1230 * fdtdec_get_srcname() - Get the name of where the devicetree comes from
1232 * Return: source name
1234 const char *fdtdec_get_srcname(void);