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 * Make sure we have a valid fdt available to control U-Boot.
560 * If not, a message is printed to the console if the console is ready.
562 * Return: 0 if all ok, -1 if not
564 int fdtdec_prepare_fdt(void);
567 * Checks that we have a valid fdt available to control U-Boot.
569 * However, if not then for the moment nothing is done, since this function
570 * is called too early to panic().
574 int fdtdec_check_fdt(void);
577 * Find the nodes for a peripheral and return a list of them in the correct
578 * order. This is used to enumerate all the peripherals of a certain type.
580 * To use this, optionally set up a /aliases node with alias properties for
581 * a peripheral. For example, for usb you could have:
584 * usb0 = "/ehci@c5008000";
585 * usb1 = "/ehci@c5000000";
588 * Pass "usb" as the name to this function and will return a list of two
589 * nodes offsets: /ehci@c5008000 and ehci@c5000000.
591 * All nodes returned will match the compatible ID, as it is assumed that
592 * all peripherals use the same driver.
594 * If no alias node is found, then the node list will be returned in the
595 * order found in the fdt. If the aliases mention a node which doesn't
596 * exist, then this will be ignored. If nodes are found with no aliases,
597 * they will be added in any order.
599 * If there is a gap in the aliases, then this function return a 0 node at
600 * that position. The return value will also count these gaps.
602 * This function checks node properties and will not return nodes which are
603 * marked disabled (status = "disabled").
605 * @param blob FDT blob to use
606 * @param name Root name of alias to search for
607 * @param id Compatible ID to look for
608 * @param node_list Place to put list of found nodes
609 * @param maxcount Maximum number of nodes to find
610 * Return: number of nodes found on success, FDT_ERR_... on error
612 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
613 enum fdt_compat_id id, int *node_list, int maxcount);
616 * This function is similar to fdtdec_find_aliases_for_id() except that it
617 * adds to the node_list that is passed in. Any 0 elements are considered
618 * available for allocation - others are considered already used and are
621 * You can use this by calling fdtdec_find_aliases_for_id() with an
622 * uninitialised array, then setting the elements that are returned to -1,
623 * say, then calling this function, perhaps with a different compat id.
624 * Any elements you get back that are >0 are new nodes added by the call
627 * Note that if you have some nodes with aliases and some without, you are
628 * sailing close to the wind. The call to fdtdec_find_aliases_for_id() with
629 * one compat_id may fill in positions for which you have aliases defined
630 * for another compat_id. When you later call *this* function with the second
631 * compat_id, the alias positions may already be used. A debug warning may
632 * be generated in this case, but it is safest to define aliases for all
633 * nodes when you care about the ordering.
635 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
636 enum fdt_compat_id id, int *node_list, int maxcount);
639 * Get the alias sequence number of a node
641 * This works out whether a node is pointed to by an alias, and if so, the
642 * sequence number of that alias. Aliases are of the form <base><num> where
643 * <num> is the sequence number. For example spi2 would be sequence number
646 * @param blob Device tree blob (if NULL, then error is returned)
647 * @param base Base name for alias (before the underscore)
648 * @param node Node to look up
649 * @param seqp This is set to the sequence number if one is found,
650 * but otherwise the value is left alone
651 * Return: 0 if a sequence was found, -ve if not
653 int fdtdec_get_alias_seq(const void *blob, const char *base, int node,
657 * Get the highest alias number for susbystem.
659 * It parses all aliases and find out highest recorded alias for subsystem.
660 * Aliases are of the form <base><num> where <num> is the sequence number.
662 * @param blob Device tree blob (if NULL, then error is returned)
663 * @param base Base name for alias susbystem (before the number)
665 * Return: 0 highest alias ID, -1 if not found
667 int fdtdec_get_alias_highest_id(const void *blob, const char *base);
670 * Get a property from the /chosen node
672 * @param blob Device tree blob (if NULL, then NULL is returned)
673 * @param name Property name to look up
674 * Return: Value of property, or NULL if it does not exist
676 const char *fdtdec_get_chosen_prop(const void *blob, const char *name);
679 * Get the offset of the given /chosen node
681 * This looks up a property in /chosen containing the path to another node,
682 * then finds the offset of that node.
684 * @param blob Device tree blob (if NULL, then error is returned)
685 * @param name Property name, e.g. "stdout-path"
686 * Return: Node offset referred to by that chosen node, or -ve FDT_ERR_...
688 int fdtdec_get_chosen_node(const void *blob, const char *name);
691 * Get the name for a compatible ID
693 * @param id Compatible ID to look for
694 * Return: compatible string for that id
696 const char *fdtdec_get_compatible(enum fdt_compat_id id);
698 /* Look up a phandle and follow it to its node. Then return the offset
701 * @param blob FDT blob
702 * @param node node to examine
703 * @param prop_name name of property to find
704 * Return: node offset if found, -ve error code on error
706 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name);
709 * Look up a property in a node and return its contents in an integer
710 * array of given length. The property must have at least enough data for
711 * the array (4*count bytes). It may have more, but this will be ignored.
713 * @param blob FDT blob
714 * @param node node to examine
715 * @param prop_name name of property to find
716 * @param array array to fill with data
717 * @param count number of array elements
718 * Return: 0 if ok, or -FDT_ERR_NOTFOUND if the property is not found,
719 * or -FDT_ERR_BADLAYOUT if not enough data
721 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
722 u32 *array, int count);
725 * Look up a property in a node and return its contents in an integer
726 * array of given length. The property must exist but may have less data that
727 * expected (4*count bytes). It may have more, but this will be ignored.
729 * @param blob FDT blob
730 * @param node node to examine
731 * @param prop_name name of property to find
732 * @param array array to fill with data
733 * @param count number of array elements
734 * Return: number of array elements if ok, or -FDT_ERR_NOTFOUND if the
735 * property is not found
737 int fdtdec_get_int_array_count(const void *blob, int node,
738 const char *prop_name, u32 *array, int count);
741 * Look up a property in a node and return a pointer to its contents as a
742 * unsigned int array of given length. The property must have at least enough
743 * data for the array ('count' cells). It may have more, but this will be
744 * ignored. The data is not copied.
746 * Note that you must access elements of the array with fdt32_to_cpu(),
747 * since the elements will be big endian even on a little endian machine.
749 * @param blob FDT blob
750 * @param node node to examine
751 * @param prop_name name of property to find
752 * @param count number of array elements
753 * Return: pointer to array if found, or NULL if the property is not
754 * found or there is not enough data
756 const u32 *fdtdec_locate_array(const void *blob, int node,
757 const char *prop_name, int count);
760 * Look up a boolean property in a node and return it.
762 * A boolean properly is true if present in the device tree and false if not
763 * present, regardless of its value.
765 * @param blob FDT blob
766 * @param node node to examine
767 * @param prop_name name of property to find
768 * Return: 1 if the properly is present; 0 if it isn't present
770 int fdtdec_get_bool(const void *blob, int node, const char *prop_name);
773 * Count child nodes of one parent node.
775 * @param blob FDT blob
776 * @param node parent node
777 * Return: number of child node; 0 if there is not child node
779 int fdtdec_get_child_count(const void *blob, int node);
782 * Look up a property in a node and return its contents in a byte
783 * array of given length. The property must have at least enough data for
784 * the array (count bytes). It may have more, but this will be ignored.
786 * @param blob FDT blob
787 * @param node node to examine
788 * @param prop_name name of property to find
789 * @param array array to fill with data
790 * @param count number of array elements
791 * Return: 0 if ok, or -FDT_ERR_MISSING if the property is not found,
792 * or -FDT_ERR_BADLAYOUT if not enough data
794 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
795 u8 *array, int count);
798 * Look up a property in a node and return a pointer to its contents as a
799 * byte array of given length. The property must have at least enough data
800 * for the array (count bytes). It may have more, but this will be ignored.
801 * The data is not copied.
803 * @param blob FDT blob
804 * @param node node to examine
805 * @param prop_name name of property to find
806 * @param count number of array elements
807 * Return: pointer to byte array if found, or NULL if the property is not
808 * found or there is not enough data
810 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
811 const char *prop_name, int count);
814 * Obtain an indexed resource from a device property.
816 * @param fdt FDT blob
817 * @param node node to examine
818 * @param property name of the property to parse
819 * @param index index of the resource to retrieve
820 * @param res returns the resource
821 * Return: 0 if ok, negative on error
823 int fdt_get_resource(const void *fdt, int node, const char *property,
824 unsigned int index, struct fdt_resource *res);
827 * Obtain a named resource from a device property.
829 * Look up the index of the name in a list of strings and return the resource
832 * @param fdt FDT blob
833 * @param node node to examine
834 * @param property name of the property to parse
835 * @param prop_names name of the property containing the list of names
836 * @param name the name of the entry to look up
837 * @param res returns the resource
839 int fdt_get_named_resource(const void *fdt, int node, const char *property,
840 const char *prop_names, const char *name,
841 struct fdt_resource *res);
843 /* Display timings from linux include/video/display_timing.h */
845 DISPLAY_FLAGS_HSYNC_LOW = 1 << 0,
846 DISPLAY_FLAGS_HSYNC_HIGH = 1 << 1,
847 DISPLAY_FLAGS_VSYNC_LOW = 1 << 2,
848 DISPLAY_FLAGS_VSYNC_HIGH = 1 << 3,
850 /* data enable flag */
851 DISPLAY_FLAGS_DE_LOW = 1 << 4,
852 DISPLAY_FLAGS_DE_HIGH = 1 << 5,
853 /* drive data on pos. edge */
854 DISPLAY_FLAGS_PIXDATA_POSEDGE = 1 << 6,
855 /* drive data on neg. edge */
856 DISPLAY_FLAGS_PIXDATA_NEGEDGE = 1 << 7,
857 DISPLAY_FLAGS_INTERLACED = 1 << 8,
858 DISPLAY_FLAGS_DOUBLESCAN = 1 << 9,
859 DISPLAY_FLAGS_DOUBLECLK = 1 << 10,
863 * A single signal can be specified via a range of minimal and maximal values
864 * with a typical value, that lies somewhere inbetween.
866 struct timing_entry {
873 * Single "mode" entry. This describes one set of signal timings a display can
874 * have in one setting. This struct can later be converted to struct videomode
875 * (see include/video/videomode.h). As each timing_entry can be defined as a
876 * range, one struct display_timing may become multiple struct videomodes.
878 * Example: hsync active high, vsync active low
881 * Video ______________________XXXXXXXXXXXXXXXXXXXXXX_____________________
882 * |<- sync ->|<- back ->|<----- active ----->|<- front ->|<- sync..
883 * | | porch | | porch |
885 * HSync _|¯¯¯¯¯¯¯¯¯¯|___________________________________________|¯¯¯¯¯¯¯¯¯
887 * VSync ¯|__________|¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯|_________
889 struct display_timing {
890 struct timing_entry pixelclock;
892 struct timing_entry hactive; /* hor. active video */
893 struct timing_entry hfront_porch; /* hor. front porch */
894 struct timing_entry hback_porch; /* hor. back porch */
895 struct timing_entry hsync_len; /* hor. sync len */
897 struct timing_entry vactive; /* ver. active video */
898 struct timing_entry vfront_porch; /* ver. front porch */
899 struct timing_entry vback_porch; /* ver. back porch */
900 struct timing_entry vsync_len; /* ver. sync len */
902 enum display_flags flags; /* display flags */
903 bool hdmi_monitor; /* is hdmi monitor? */
907 * fdtdec_decode_display_timing() - decode display timings
909 * Decode display timings from the supplied 'display-timings' node.
910 * See doc/device-tree-bindings/video/display-timing.txt for binding
913 * @param blob FDT blob
914 * @param node 'display-timing' node containing the timing subnodes
915 * @param index Index number to read (0=first timing subnode)
916 * @param config Place to put timings
917 * Return: 0 if OK, -FDT_ERR_NOTFOUND if not found
919 int fdtdec_decode_display_timing(const void *blob, int node, int index,
920 struct display_timing *config);
923 * fdtdec_setup_mem_size_base() - decode and setup gd->ram_size and
926 * Decode the /memory 'reg' property to determine the size and start of the
927 * first memory bank, populate the global data with the size and start of the
928 * first bank of memory.
930 * This function should be called from a boards dram_init(). This helper
931 * function allows for boards to query the device tree for DRAM size and start
932 * address instead of hard coding the value in the case where the memory size
933 * and start address cannot be detected automatically.
935 * Return: 0 if OK, -EINVAL if the /memory node or reg property is missing or
938 int fdtdec_setup_mem_size_base(void);
941 * fdtdec_setup_mem_size_base_lowest() - decode and setup gd->ram_size and
942 * gd->ram_start by lowest available memory base
944 * Decode the /memory 'reg' property to determine the lowest start of the memory
945 * bank bank and populate the global data with it.
947 * This function should be called from a boards dram_init(). This helper
948 * function allows for boards to query the device tree for DRAM size and start
949 * address instead of hard coding the value in the case where the memory size
950 * and start address cannot be detected automatically.
952 * Return: 0 if OK, -EINVAL if the /memory node or reg property is missing or
955 int fdtdec_setup_mem_size_base_lowest(void);
958 * fdtdec_setup_memory_banksize() - decode and populate gd->bd->bi_dram
960 * Decode the /memory 'reg' property to determine the address and size of the
961 * memory banks. Use this data to populate the global data board info with the
962 * phys address and size of memory banks.
964 * This function should be called from a boards dram_init_banksize(). This
965 * helper function allows for boards to query the device tree for memory bank
966 * information instead of hard coding the information in cases where it cannot
967 * be detected automatically.
969 * Return: 0 if OK, -EINVAL if the /memory node or reg property is missing or
972 int fdtdec_setup_memory_banksize(void);
975 * fdtdec_set_ethernet_mac_address() - set MAC address for default interface
977 * Looks up the default interface via the "ethernet" alias (in the /aliases
978 * node) and stores the given MAC in its "local-mac-address" property. This
979 * is useful on platforms that store the MAC address in a custom location.
980 * Board code can call this in the late init stage to make sure that the
981 * interface device tree node has the right MAC address configured for the
982 * Ethernet uclass to pick it up.
984 * Typically the FDT passed into this function will be U-Boot's control DTB.
985 * Given that a lot of code may be holding offsets to various nodes in that
986 * tree, this code will only set the "local-mac-address" property in-place,
987 * which means that it needs to exist and have space for the 6-byte address.
988 * This ensures that the operation is non-destructive and does not invalidate
989 * offsets that other drivers may be using.
991 * @param fdt FDT blob
992 * @param mac buffer containing the MAC address to set
993 * @param size size of MAC address
994 * Return: 0 on success or a negative error code on failure
996 int fdtdec_set_ethernet_mac_address(void *fdt, const u8 *mac, size_t size);
999 * fdtdec_set_phandle() - sets the phandle of a given node
1001 * @param blob FDT blob
1002 * @param node offset in the FDT blob of the node whose phandle is to
1004 * @param phandle phandle to set for the given node
1005 * Return: 0 on success or a negative error code on failure
1007 static inline int fdtdec_set_phandle(void *blob, int node, uint32_t phandle)
1009 return fdt_setprop_u32(blob, node, "phandle", phandle);
1012 /* add "no-map" property */
1013 #define FDTDEC_RESERVED_MEMORY_NO_MAP (1 << 0)
1016 * fdtdec_add_reserved_memory() - add or find a reserved-memory node
1018 * If a reserved-memory node already exists for the given carveout, a phandle
1019 * for that node will be returned. Otherwise a new node will be created and a
1020 * phandle corresponding to it will be returned.
1022 * See Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt
1023 * for details on how to use reserved memory regions.
1025 * As an example, consider the following code snippet:
1027 * struct fdt_memory fb = {
1028 * .start = 0x92cb3000,
1029 * .end = 0x934b2fff,
1033 * fdtdec_add_reserved_memory(fdt, "framebuffer", &fb, NULL, 0, &phandle,
1036 * This results in the following subnode being added to the top-level
1037 * /reserved-memory node:
1040 * #address-cells = <0x00000002>;
1041 * #size-cells = <0x00000002>;
1044 * framebuffer@92cb3000 {
1045 * reg = <0x00000000 0x92cb3000 0x00000000 0x00800000>;
1046 * phandle = <0x0000004d>;
1050 * If the top-level /reserved-memory node does not exist, it will be created.
1051 * The phandle returned from the function call can be used to reference this
1052 * reserved memory region from other nodes.
1054 * See fdtdec_set_carveout() for a more elaborate example.
1056 * @param blob FDT blob
1057 * @param basename base name of the node to create
1058 * @param carveout information about the carveout region
1059 * @param compatibles list of compatible strings for the carveout region
1060 * @param count number of compatible strings for the carveout region
1061 * @param phandlep return location for the phandle of the carveout region
1062 * can be NULL if no phandle should be added
1063 * @param flags bitmask of flags to set for the carveout region
1064 * Return: 0 on success or a negative error code on failure
1066 int fdtdec_add_reserved_memory(void *blob, const char *basename,
1067 const struct fdt_memory *carveout,
1068 const char **compatibles, unsigned int count,
1069 uint32_t *phandlep, unsigned long flags);
1072 * fdtdec_get_carveout() - reads a carveout from an FDT
1074 * Reads information about a carveout region from an FDT. The carveout is a
1075 * referenced by its phandle that is read from a given property in a given
1078 * @param blob FDT blob
1079 * @param node name of a node
1080 * @param prop_name name of the property in the given node that contains
1081 * the phandle for the carveout
1082 * @param index index of the phandle for which to read the carveout
1083 * @param carveout return location for the carveout information
1084 * @param name return location for the carveout name
1085 * @param compatiblesp return location for compatible strings
1086 * @param countp return location for the number of compatible strings
1087 * @param flags return location for the flags of the carveout
1088 * Return: 0 on success or a negative error code on failure
1090 int fdtdec_get_carveout(const void *blob, const char *node,
1091 const char *prop_name, unsigned int index,
1092 struct fdt_memory *carveout, const char **name,
1093 const char ***compatiblesp, unsigned int *countp,
1094 unsigned long *flags);
1097 * fdtdec_set_carveout() - sets a carveout region for a given node
1099 * Sets a carveout region for a given node. If a reserved-memory node already
1100 * exists for the carveout, the phandle for that node will be reused. If no
1101 * such node exists, a new one will be created and a phandle to it stored in
1102 * a specified property of the given node.
1104 * As an example, consider the following code snippet:
1106 * const char *node = "/host1x@50000000/dc@54240000";
1107 * struct fdt_memory fb = {
1108 * .start = 0x92cb3000,
1109 * .end = 0x934b2fff,
1112 * fdtdec_set_carveout(fdt, node, "memory-region", 0, "framebuffer", NULL,
1115 * dc@54200000 is a display controller and was set up by the bootloader to
1116 * scan out the framebuffer specified by "fb". This would cause the following
1117 * reserved memory region to be added:
1120 * #address-cells = <0x00000002>;
1121 * #size-cells = <0x00000002>;
1124 * framebuffer@92cb3000 {
1125 * reg = <0x00000000 0x92cb3000 0x00000000 0x00800000>;
1126 * phandle = <0x0000004d>;
1130 * A "memory-region" property will also be added to the node referenced by the
1138 * memory-region = <0x0000004d>;
1145 * @param blob FDT blob
1146 * @param node name of the node to add the carveout to
1147 * @param prop_name name of the property in which to store the phandle of
1149 * @param index index of the phandle to store
1150 * @param carveout information about the carveout to add
1151 * @param name base name of the reserved-memory node to create
1152 * @param compatibles compatible strings to set for the carveout
1153 * @param count number of compatible strings
1154 * @param flags bitmask of flags to set for the carveout
1155 * Return: 0 on success or a negative error code on failure
1157 int fdtdec_set_carveout(void *blob, const char *node, const char *prop_name,
1158 unsigned int index, const struct fdt_memory *carveout,
1159 const char *name, const char **compatibles,
1160 unsigned int count, unsigned long flags);
1163 * Set up the device tree ready for use
1165 int fdtdec_setup(void);
1168 * Perform board-specific early DT adjustments
1170 int fdtdec_board_setup(const void *fdt_blob);
1173 * fdtdec_resetup() - Set up the device tree again
1175 * The main difference with fdtdec_setup() is that it returns if the fdt has
1176 * changed because a better match has been found.
1177 * This is typically used for boards that rely on a DM driver to detect the
1178 * board type. This function sould be called by the board code after the stuff
1179 * needed by board_fit_config_name_match() to operate porperly is available.
1180 * If this functions signals that a rescan is necessary, the board code must
1181 * unbind all the drivers using dm_uninit() and then rescan the DT with
1182 * dm_init_and_scan().
1184 * @param rescan Returns a flag indicating that fdt has changed and rescanning
1185 * the fdt is required
1187 * Return: 0 if OK, -ve on error
1189 int fdtdec_resetup(int *rescan);
1192 * Board-specific FDT initialization. Returns the address to a device tree blob.
1194 * Called when CONFIG_OF_BOARD is defined.
1196 * The existing devicetree is available at gd->fdt_blob
1198 * @err internal error code if we fail to setup a DTB
1199 * @returns new devicetree blob pointer
1201 void *board_fdt_blob_setup(int *err);
1204 * Decode the size of memory
1206 * RAM size is normally set in a /memory node and consists of a list of
1207 * (base, size) cells in the 'reg' property. This information is used to
1208 * determine the total available memory as well as the address and size
1211 * Optionally the memory configuration can vary depending on a board id,
1212 * typically read from strapping resistors or an EEPROM on the board.
1214 * Finally, memory size can be detected (within certain limits) by probing
1215 * the available memory. It is safe to do so within the limits provides by
1216 * the board's device tree information. This makes it possible to produce
1217 * boards with different memory sizes, where the device tree specifies the
1218 * maximum memory configuration, and the smaller memory configuration is
1221 * This function decodes that information, returning the memory base address,
1222 * size and bank information. See the memory.txt binding for full
1225 * @param blob Device tree blob
1226 * @param area Name of node to check (NULL means "/memory")
1227 * @param board_id Board ID to look up
1228 * @param basep Returns base address of first memory bank (NULL to
1230 * @param sizep Returns total memory size (NULL to ignore)
1231 * @param bd Updated with the memory bank information (NULL to skip)
1232 * Return: 0 if OK, -ve on error
1234 int fdtdec_decode_ram_size(const void *blob, const char *area, int board_id,
1235 phys_addr_t *basep, phys_size_t *sizep,
1236 struct bd_info *bd);
1239 * fdtdec_get_srcname() - Get the name of where the devicetree comes from
1241 * Return: source name
1243 const char *fdtdec_get_srcname(void);