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_ADDR_T_NONE (-1U)
28 #define FDT_SIZE_T_NONE (-1U)
30 #ifdef CONFIG_PHYS_64BIT
31 #define fdt_addr_to_cpu(reg) be64_to_cpu(reg)
32 #define fdt_size_to_cpu(reg) be64_to_cpu(reg)
33 #define cpu_to_fdt_addr(reg) cpu_to_be64(reg)
34 #define cpu_to_fdt_size(reg) cpu_to_be64(reg)
35 typedef fdt64_t fdt_val_t;
37 #define fdt_addr_to_cpu(reg) be32_to_cpu(reg)
38 #define fdt_size_to_cpu(reg) be32_to_cpu(reg)
39 #define cpu_to_fdt_addr(reg) cpu_to_be32(reg)
40 #define cpu_to_fdt_size(reg) cpu_to_be32(reg)
41 typedef fdt32_t fdt_val_t;
44 /* Information obtained about memory from the FDT */
52 #ifdef CONFIG_SPL_BUILD
58 #ifdef CONFIG_OF_PRIOR_STAGE
59 extern phys_addr_t prior_stage_fdt_address;
63 * Information about a resource. start is the first address of the resource
64 * and end is the last address (inclusive). The length of the resource will
65 * be equal to: end - start + 1.
73 FDT_PCI_SPACE_CONFIG = 0,
74 FDT_PCI_SPACE_IO = 0x01000000,
75 FDT_PCI_SPACE_MEM32 = 0x02000000,
76 FDT_PCI_SPACE_MEM64 = 0x03000000,
77 FDT_PCI_SPACE_MEM32_PREF = 0x42000000,
78 FDT_PCI_SPACE_MEM64_PREF = 0x43000000,
81 #define FDT_PCI_ADDR_CELLS 3
82 #define FDT_PCI_SIZE_CELLS 2
83 #define FDT_PCI_REG_SIZE \
84 ((FDT_PCI_ADDR_CELLS + FDT_PCI_SIZE_CELLS) * sizeof(u32))
87 * The Open Firmware spec defines PCI physical address as follows:
89 * bits# 31 .... 24 23 .... 16 15 .... 08 07 .... 00
91 * phys.hi cell: npt000ss bbbbbbbb dddddfff rrrrrrrr
92 * phys.mid cell: hhhhhhhh hhhhhhhh hhhhhhhh hhhhhhhh
93 * phys.lo cell: llllllll llllllll llllllll llllllll
97 * n: is 0 if the address is relocatable, 1 otherwise
98 * p: is 1 if addressable region is prefetchable, 0 otherwise
99 * t: is 1 if the address is aliased (for non-relocatable I/O) below 1MB
100 * (for Memory), or below 64KB (for relocatable I/O)
101 * ss: is the space code, denoting the address space
102 * bbbbbbbb: is the 8-bit Bus Number
103 * ddddd: is the 5-bit Device Number
104 * fff: is the 3-bit Function Number
105 * rrrrrrrr: is the 8-bit Register Number
106 * hhhhhhhh: is a 32-bit unsigned number
107 * llllllll: is a 32-bit unsigned number
109 struct fdt_pci_addr {
115 extern u8 __dtb_dt_begin[]; /* embedded device tree blob */
116 extern u8 __dtb_dt_spl_begin[]; /* embedded device tree blob for SPL/TPL */
119 * Compute the size of a resource.
121 * @param res the resource to operate on
122 * @return the size of the resource
124 static inline fdt_size_t fdt_resource_size(const struct fdt_resource *res)
126 return res->end - res->start + 1;
130 * Compat types that we know about and for which we might have drivers.
131 * Each is named COMPAT_<dir>_<filename> where <dir> is the directory
136 COMPAT_NVIDIA_TEGRA20_EMC, /* Tegra20 memory controller */
137 COMPAT_NVIDIA_TEGRA20_EMC_TABLE, /* Tegra20 memory timing table */
138 COMPAT_NVIDIA_TEGRA20_NAND, /* Tegra2 NAND controller */
139 COMPAT_NVIDIA_TEGRA124_XUSB_PADCTL,
140 /* Tegra124 XUSB pad controller */
141 COMPAT_NVIDIA_TEGRA210_XUSB_PADCTL,
142 /* Tegra210 XUSB pad controller */
143 COMPAT_SAMSUNG_EXYNOS_USB_PHY, /* Exynos phy controller for usb2.0 */
144 COMPAT_SAMSUNG_EXYNOS5_USB3_PHY,/* Exynos phy controller for usb3.0 */
145 COMPAT_SAMSUNG_EXYNOS_TMU, /* Exynos TMU */
146 COMPAT_SAMSUNG_EXYNOS_MIPI_DSI, /* Exynos mipi dsi */
147 COMPAT_SAMSUNG_EXYNOS_DWMMC, /* Exynos DWMMC controller */
148 COMPAT_GENERIC_SPI_FLASH, /* Generic SPI Flash chip */
149 COMPAT_SAMSUNG_EXYNOS_SYSMMU, /* Exynos sysmmu */
150 COMPAT_INTEL_MICROCODE, /* Intel microcode update */
151 COMPAT_INTEL_QRK_MRC, /* Intel Quark MRC */
152 COMPAT_ALTERA_SOCFPGA_DWMAC, /* SoCFPGA Ethernet controller */
153 COMPAT_ALTERA_SOCFPGA_DWMMC, /* SoCFPGA DWMMC controller */
154 COMPAT_ALTERA_SOCFPGA_DWC2USB, /* SoCFPGA DWC2 USB controller */
155 COMPAT_INTEL_BAYTRAIL_FSP, /* Intel Bay Trail FSP */
156 COMPAT_INTEL_BAYTRAIL_FSP_MDP, /* Intel FSP memory-down params */
157 COMPAT_INTEL_IVYBRIDGE_FSP, /* Intel Ivy Bridge FSP */
158 COMPAT_SUNXI_NAND, /* SUNXI NAND controller */
159 COMPAT_ALTERA_SOCFPGA_CLK, /* SoCFPGA Clock initialization */
160 COMPAT_ALTERA_SOCFPGA_PINCTRL_SINGLE, /* SoCFPGA pinctrl-single */
161 COMPAT_ALTERA_SOCFPGA_H2F_BRG, /* SoCFPGA hps2fpga bridge */
162 COMPAT_ALTERA_SOCFPGA_LWH2F_BRG, /* SoCFPGA lwhps2fpga bridge */
163 COMPAT_ALTERA_SOCFPGA_F2H_BRG, /* SoCFPGA fpga2hps bridge */
164 COMPAT_ALTERA_SOCFPGA_F2SDR0, /* SoCFPGA fpga2SDRAM0 bridge */
165 COMPAT_ALTERA_SOCFPGA_F2SDR1, /* SoCFPGA fpga2SDRAM1 bridge */
166 COMPAT_ALTERA_SOCFPGA_F2SDR2, /* SoCFPGA fpga2SDRAM2 bridge */
167 COMPAT_ALTERA_SOCFPGA_FPGA0, /* SOCFPGA FPGA manager */
168 COMPAT_ALTERA_SOCFPGA_NOC, /* SOCFPGA Arria 10 NOC */
169 COMPAT_ALTERA_SOCFPGA_CLK_INIT, /* SOCFPGA Arria 10 clk init */
174 #define MAX_PHANDLE_ARGS 16
175 struct fdtdec_phandle_args {
178 uint32_t args[MAX_PHANDLE_ARGS];
182 * fdtdec_parse_phandle_with_args() - Find a node pointed by phandle in a list
184 * This function is useful to parse lists of phandles and their arguments.
197 * list = <&phandle1 1 2 &phandle2 3>;
200 * To get a device_node of the `node2' node you may call this:
201 * fdtdec_parse_phandle_with_args(blob, node3, "list", "#list-cells", 0, 1,
204 * (This function is a modified version of __of_parse_phandle_with_args() from
207 * @blob: Pointer to device tree
208 * @src_node: Offset of device tree node containing a list
209 * @list_name: property name that contains a list
210 * @cells_name: property name that specifies the phandles' arguments count,
211 * or NULL to use @cells_count
212 * @cells_count: Cell count to use if @cells_name is NULL
213 * @index: index of a phandle to parse out
214 * @out_args: optional pointer to output arguments structure (will be filled)
215 * @return 0 on success (with @out_args filled out if not NULL), -ENOENT if
216 * @list_name does not exist, a phandle was not found, @cells_name
217 * could not be found, the arguments were truncated or there were too
221 int fdtdec_parse_phandle_with_args(const void *blob, int src_node,
222 const char *list_name,
223 const char *cells_name,
224 int cell_count, int index,
225 struct fdtdec_phandle_args *out_args);
228 * Find the next numbered alias for a peripheral. This is used to enumerate
229 * all the peripherals of a certain type.
231 * Do the first call with *upto = 0. Assuming /aliases/<name>0 exists then
232 * this function will return a pointer to the node the alias points to, and
233 * then update *upto to 1. Next time you call this function, the next node
236 * All nodes returned will match the compatible ID, as it is assumed that
237 * all peripherals use the same driver.
239 * @param blob FDT blob to use
240 * @param name Root name of alias to search for
241 * @param id Compatible ID to look for
242 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
244 int fdtdec_next_alias(const void *blob, const char *name,
245 enum fdt_compat_id id, int *upto);
248 * Find the compatible ID for a given node.
250 * Generally each node has at least one compatible string attached to it.
251 * This function looks through our list of known compatible strings and
252 * returns the corresponding ID which matches the compatible string.
254 * @param blob FDT blob to use
255 * @param node Node containing compatible string to find
256 * @return compatible ID, or COMPAT_UNKNOWN if we cannot find a match
258 enum fdt_compat_id fdtdec_lookup(const void *blob, int node);
261 * Find the next compatible node for a peripheral.
263 * Do the first call with node = 0. This function will return a pointer to
264 * the next compatible node. Next time you call this function, pass the
265 * value returned, and the next node will be provided.
267 * @param blob FDT blob to use
268 * @param node Start node for search
269 * @param id Compatible ID to look for (enum fdt_compat_id)
270 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
272 int fdtdec_next_compatible(const void *blob, int node,
273 enum fdt_compat_id id);
276 * Find the next compatible subnode for a peripheral.
278 * Do the first call with node set to the parent and depth = 0. This
279 * function will return the offset of the next compatible node. Next time
280 * you call this function, pass the node value returned last time, with
281 * depth unchanged, and the next node will be provided.
283 * @param blob FDT blob to use
284 * @param node Start node for search
285 * @param id Compatible ID to look for (enum fdt_compat_id)
286 * @param depthp Current depth (set to 0 before first call)
287 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
289 int fdtdec_next_compatible_subnode(const void *blob, int node,
290 enum fdt_compat_id id, int *depthp);
293 * Look up an address property in a node and return the parsed address, and
294 * optionally the parsed size.
296 * This variant assumes a known and fixed number of cells are used to
297 * represent the address and size.
299 * You probably don't want to use this function directly except to parse
300 * non-standard properties, and never to parse the "reg" property. Instead,
301 * use one of the "auto" variants below, which automatically honor the
302 * #address-cells and #size-cells properties in the parent node.
304 * @param blob FDT blob
305 * @param node node to examine
306 * @param prop_name name of property to find
307 * @param index which address to retrieve from a list of addresses. Often 0.
308 * @param na the number of cells used to represent an address
309 * @param ns the number of cells used to represent a size
310 * @param sizep a pointer to store the size into. Use NULL if not required
311 * @param translate Indicates whether to translate the returned value
312 * using the parent node's ranges property.
313 * @return address, if found, or FDT_ADDR_T_NONE if not
315 fdt_addr_t fdtdec_get_addr_size_fixed(const void *blob, int node,
316 const char *prop_name, int index, int na, int ns,
317 fdt_size_t *sizep, bool translate);
320 * Look up an address property in a node and return the parsed address, and
321 * optionally the parsed size.
323 * This variant automatically determines the number of cells used to represent
324 * the address and size by parsing the provided parent node's #address-cells
325 * and #size-cells properties.
327 * @param blob FDT blob
328 * @param parent parent node of @node
329 * @param node node to examine
330 * @param prop_name name of property to find
331 * @param index which address to retrieve from a list of addresses. Often 0.
332 * @param sizep a pointer to store the size into. Use NULL if not required
333 * @param translate Indicates whether to translate the returned value
334 * using the parent node's ranges property.
335 * @return address, if found, or FDT_ADDR_T_NONE if not
337 fdt_addr_t fdtdec_get_addr_size_auto_parent(const void *blob, int parent,
338 int node, const char *prop_name, int index, fdt_size_t *sizep,
342 * Look up an address property in a node and return the parsed address, and
343 * optionally the parsed size.
345 * This variant automatically determines the number of cells used to represent
346 * the address and size by parsing the parent node's #address-cells
347 * and #size-cells properties. The parent node is automatically found.
349 * The automatic parent lookup implemented by this function is slow.
350 * Consequently, fdtdec_get_addr_size_auto_parent() should be used where
353 * @param blob FDT blob
354 * @param parent parent node of @node
355 * @param node node to examine
356 * @param prop_name name of property to find
357 * @param index which address to retrieve from a list of addresses. Often 0.
358 * @param sizep a pointer to store the size into. Use NULL if not required
359 * @param translate Indicates whether to translate the returned value
360 * using the parent node's ranges property.
361 * @return address, if found, or FDT_ADDR_T_NONE if not
363 fdt_addr_t fdtdec_get_addr_size_auto_noparent(const void *blob, int node,
364 const char *prop_name, int index, fdt_size_t *sizep,
368 * Look up an address property in a node and return the parsed address.
370 * This variant hard-codes the number of cells used to represent the address
371 * and size based on sizeof(fdt_addr_t) and sizeof(fdt_size_t). It also
372 * always returns the first address value in the property (index 0).
374 * Use of this function is not recommended due to the hard-coding of cell
375 * counts. There is no programmatic validation that these hard-coded values
376 * actually match the device tree content in any way at all. This assumption
377 * can be satisfied by manually ensuring CONFIG_PHYS_64BIT is appropriately
378 * set in the U-Boot build and exercising strict control over DT content to
379 * ensure use of matching #address-cells/#size-cells properties. However, this
380 * approach is error-prone; those familiar with DT will not expect the
381 * assumption to exist, and could easily invalidate it. If the assumption is
382 * invalidated, this function will not report the issue, and debugging will
383 * be required. Instead, use fdtdec_get_addr_size_auto_parent().
385 * @param blob FDT blob
386 * @param node node to examine
387 * @param prop_name name of property to find
388 * @return address, if found, or FDT_ADDR_T_NONE if not
390 fdt_addr_t fdtdec_get_addr(const void *blob, int node,
391 const char *prop_name);
394 * Look up an address property in a node and return the parsed address, and
395 * optionally the parsed size.
397 * This variant hard-codes the number of cells used to represent the address
398 * and size based on sizeof(fdt_addr_t) and sizeof(fdt_size_t). It also
399 * always returns the first address value in the property (index 0).
401 * Use of this function is not recommended due to the hard-coding of cell
402 * counts. There is no programmatic validation that these hard-coded values
403 * actually match the device tree content in any way at all. This assumption
404 * can be satisfied by manually ensuring CONFIG_PHYS_64BIT is appropriately
405 * set in the U-Boot build and exercising strict control over DT content to
406 * ensure use of matching #address-cells/#size-cells properties. However, this
407 * approach is error-prone; those familiar with DT will not expect the
408 * assumption to exist, and could easily invalidate it. If the assumption is
409 * invalidated, this function will not report the issue, and debugging will
410 * be required. Instead, use fdtdec_get_addr_size_auto_parent().
412 * @param blob FDT blob
413 * @param node node to examine
414 * @param prop_name name of property to find
415 * @param sizep a pointer to store the size into. Use NULL if not required
416 * @return address, if found, or FDT_ADDR_T_NONE if not
418 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
419 const char *prop_name, fdt_size_t *sizep);
422 * Look at the compatible property of a device node that represents a PCI
423 * device and extract pci vendor id and device id from it.
425 * @param blob FDT blob
426 * @param node node to examine
427 * @param vendor vendor id of the pci device
428 * @param device device id of the pci device
429 * @return 0 if ok, negative on error
431 int fdtdec_get_pci_vendev(const void *blob, int node,
432 u16 *vendor, u16 *device);
435 * Look at the pci address of a device node that represents a PCI device
436 * and return base address of the pci device's registers.
438 * @param dev device to examine
439 * @param addr pci address in the form of fdt_pci_addr
440 * @param bar returns base address of the pci device's registers
441 * @return 0 if ok, negative on error
443 int fdtdec_get_pci_bar32(const struct udevice *dev, struct fdt_pci_addr *addr,
447 * Look at the bus range property of a device node and return the pci bus
448 * range for this node.
449 * The property must hold one fdt_pci_addr with a length.
450 * @param blob FDT blob
451 * @param node node to examine
452 * @param res the resource structure to return the bus range
453 * @return 0 if ok, negative on error
456 int fdtdec_get_pci_bus_range(const void *blob, int node,
457 struct fdt_resource *res);
460 * Look up a 32-bit integer property in a node and return it. The property
461 * must have at least 4 bytes of data. The value of the first cell is
464 * @param blob FDT blob
465 * @param node node to examine
466 * @param prop_name name of property to find
467 * @param default_val default value to return if the property is not found
468 * @return integer value, if found, or default_val if not
470 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
474 * Unsigned version of fdtdec_get_int. The property must have at least
475 * 4 bytes of data. The value of the first cell is returned.
477 * @param blob FDT blob
478 * @param node node to examine
479 * @param prop_name name of property to find
480 * @param default_val default value to return if the property is not found
481 * @return unsigned integer value, if found, or default_val if not
483 unsigned int fdtdec_get_uint(const void *blob, int node, const char *prop_name,
484 unsigned int default_val);
487 * Get a variable-sized number from a property
489 * This reads a number from one or more cells.
491 * @param ptr Pointer to property
492 * @param cells Number of cells containing the number
493 * @return the value in the cells
495 u64 fdtdec_get_number(const fdt32_t *ptr, unsigned int cells);
498 * Look up a 64-bit integer property in a node and return it. The property
499 * must have at least 8 bytes of data (2 cells). The first two cells are
500 * concatenated to form a 8 bytes value, where the first cell is top half and
501 * the second cell is bottom half.
503 * @param blob FDT blob
504 * @param node node to examine
505 * @param prop_name name of property to find
506 * @param default_val default value to return if the property is not found
507 * @return integer value, if found, or default_val if not
509 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
510 uint64_t default_val);
513 * Checks whether a node is enabled.
514 * This looks for a 'status' property. If this exists, then returns 1 if
515 * the status is 'ok' and 0 otherwise. If there is no status property,
516 * it returns 1 on the assumption that anything mentioned should be enabled
519 * @param blob FDT blob
520 * @param node node to examine
521 * @return integer value 0 (not enabled) or 1 (enabled)
523 int fdtdec_get_is_enabled(const void *blob, int node);
526 * Make sure we have a valid fdt available to control U-Boot.
528 * If not, a message is printed to the console if the console is ready.
530 * @return 0 if all ok, -1 if not
532 int fdtdec_prepare_fdt(void);
535 * Checks that we have a valid fdt available to control U-Boot.
537 * However, if not then for the moment nothing is done, since this function
538 * is called too early to panic().
542 int fdtdec_check_fdt(void);
545 * Find the nodes for a peripheral and return a list of them in the correct
546 * order. This is used to enumerate all the peripherals of a certain type.
548 * To use this, optionally set up a /aliases node with alias properties for
549 * a peripheral. For example, for usb you could have:
552 * usb0 = "/ehci@c5008000";
553 * usb1 = "/ehci@c5000000";
556 * Pass "usb" as the name to this function and will return a list of two
557 * nodes offsets: /ehci@c5008000 and ehci@c5000000.
559 * All nodes returned will match the compatible ID, as it is assumed that
560 * all peripherals use the same driver.
562 * If no alias node is found, then the node list will be returned in the
563 * order found in the fdt. If the aliases mention a node which doesn't
564 * exist, then this will be ignored. If nodes are found with no aliases,
565 * they will be added in any order.
567 * If there is a gap in the aliases, then this function return a 0 node at
568 * that position. The return value will also count these gaps.
570 * This function checks node properties and will not return nodes which are
571 * marked disabled (status = "disabled").
573 * @param blob FDT blob to use
574 * @param name Root name of alias to search for
575 * @param id Compatible ID to look for
576 * @param node_list Place to put list of found nodes
577 * @param maxcount Maximum number of nodes to find
578 * @return number of nodes found on success, FDT_ERR_... on error
580 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
581 enum fdt_compat_id id, int *node_list, int maxcount);
584 * This function is similar to fdtdec_find_aliases_for_id() except that it
585 * adds to the node_list that is passed in. Any 0 elements are considered
586 * available for allocation - others are considered already used and are
589 * You can use this by calling fdtdec_find_aliases_for_id() with an
590 * uninitialised array, then setting the elements that are returned to -1,
591 * say, then calling this function, perhaps with a different compat id.
592 * Any elements you get back that are >0 are new nodes added by the call
595 * Note that if you have some nodes with aliases and some without, you are
596 * sailing close to the wind. The call to fdtdec_find_aliases_for_id() with
597 * one compat_id may fill in positions for which you have aliases defined
598 * for another compat_id. When you later call *this* function with the second
599 * compat_id, the alias positions may already be used. A debug warning may
600 * be generated in this case, but it is safest to define aliases for all
601 * nodes when you care about the ordering.
603 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
604 enum fdt_compat_id id, int *node_list, int maxcount);
607 * Get the alias sequence number of a node
609 * This works out whether a node is pointed to by an alias, and if so, the
610 * sequence number of that alias. Aliases are of the form <base><num> where
611 * <num> is the sequence number. For example spi2 would be sequence number
614 * @param blob Device tree blob (if NULL, then error is returned)
615 * @param base Base name for alias (before the underscore)
616 * @param node Node to look up
617 * @param seqp This is set to the sequence number if one is found,
618 * but otherwise the value is left alone
619 * @return 0 if a sequence was found, -ve if not
621 int fdtdec_get_alias_seq(const void *blob, const char *base, int node,
625 * Get the highest alias number for susbystem.
627 * It parses all aliases and find out highest recorded alias for subsystem.
628 * Aliases are of the form <base><num> where <num> is the sequence number.
630 * @param blob Device tree blob (if NULL, then error is returned)
631 * @param base Base name for alias susbystem (before the number)
633 * @return 0 highest alias ID, -1 if not found
635 int fdtdec_get_alias_highest_id(const void *blob, const char *base);
638 * Get a property from the /chosen node
640 * @param blob Device tree blob (if NULL, then NULL is returned)
641 * @param name Property name to look up
642 * @return Value of property, or NULL if it does not exist
644 const char *fdtdec_get_chosen_prop(const void *blob, const char *name);
647 * Get the offset of the given /chosen node
649 * This looks up a property in /chosen containing the path to another node,
650 * then finds the offset of that node.
652 * @param blob Device tree blob (if NULL, then error is returned)
653 * @param name Property name, e.g. "stdout-path"
654 * @return Node offset referred to by that chosen node, or -ve FDT_ERR_...
656 int fdtdec_get_chosen_node(const void *blob, const char *name);
659 * Get the name for a compatible ID
661 * @param id Compatible ID to look for
662 * @return compatible string for that id
664 const char *fdtdec_get_compatible(enum fdt_compat_id id);
666 /* Look up a phandle and follow it to its node. Then return the offset
669 * @param blob FDT blob
670 * @param node node to examine
671 * @param prop_name name of property to find
672 * @return node offset if found, -ve error code on error
674 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name);
677 * Look up a property in a node and return its contents in an integer
678 * array of given length. The property must have at least enough data for
679 * the array (4*count bytes). It may have more, but this will be ignored.
681 * @param blob FDT blob
682 * @param node node to examine
683 * @param prop_name name of property to find
684 * @param array array to fill with data
685 * @param count number of array elements
686 * @return 0 if ok, or -FDT_ERR_NOTFOUND if the property is not found,
687 * or -FDT_ERR_BADLAYOUT if not enough data
689 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
690 u32 *array, int count);
693 * Look up a property in a node and return its contents in an integer
694 * array of given length. The property must exist but may have less data that
695 * expected (4*count bytes). It may have more, but this will be ignored.
697 * @param blob FDT blob
698 * @param node node to examine
699 * @param prop_name name of property to find
700 * @param array array to fill with data
701 * @param count number of array elements
702 * @return number of array elements if ok, or -FDT_ERR_NOTFOUND if the
703 * property is not found
705 int fdtdec_get_int_array_count(const void *blob, int node,
706 const char *prop_name, u32 *array, int count);
709 * Look up a property in a node and return a pointer to its contents as a
710 * unsigned int array of given length. The property must have at least enough
711 * data for the array ('count' cells). It may have more, but this will be
712 * ignored. The data is not copied.
714 * Note that you must access elements of the array with fdt32_to_cpu(),
715 * since the elements will be big endian even on a little endian machine.
717 * @param blob FDT blob
718 * @param node node to examine
719 * @param prop_name name of property to find
720 * @param count number of array elements
721 * @return pointer to array if found, or NULL if the property is not
722 * found or there is not enough data
724 const u32 *fdtdec_locate_array(const void *blob, int node,
725 const char *prop_name, int count);
728 * Look up a boolean property in a node and return it.
730 * A boolean properly is true if present in the device tree and false if not
731 * present, regardless of its value.
733 * @param blob FDT blob
734 * @param node node to examine
735 * @param prop_name name of property to find
736 * @return 1 if the properly is present; 0 if it isn't present
738 int fdtdec_get_bool(const void *blob, int node, const char *prop_name);
741 * Count child nodes of one parent node.
743 * @param blob FDT blob
744 * @param node parent node
745 * @return number of child node; 0 if there is not child node
747 int fdtdec_get_child_count(const void *blob, int node);
750 * Look in the FDT for a config item with the given name and return its value
751 * as a 32-bit integer. The property must have at least 4 bytes of data. The
752 * value of the first cell is returned.
754 * @param blob FDT blob to use
755 * @param prop_name Node property name
756 * @param default_val default value to return if the property is not found
757 * @return integer value, if found, or default_val if not
759 int fdtdec_get_config_int(const void *blob, const char *prop_name,
763 * Look in the FDT for a config item with the given name
764 * and return whether it exists.
766 * @param blob FDT blob
767 * @param prop_name property name to look up
768 * @return 1, if it exists, or 0 if not
770 int fdtdec_get_config_bool(const void *blob, const char *prop_name);
773 * Look in the FDT for a config item with the given name and return its value
776 * @param blob FDT blob
777 * @param prop_name property name to look up
778 * @returns property string, NULL on error.
780 char *fdtdec_get_config_string(const void *blob, const char *prop_name);
783 * Look up a property in a node and return its contents in a byte
784 * array of given length. The property must have at least enough data for
785 * the array (count bytes). It may have more, but this will be ignored.
787 * @param blob FDT blob
788 * @param node node to examine
789 * @param prop_name name of property to find
790 * @param array array to fill with data
791 * @param count number of array elements
792 * @return 0 if ok, or -FDT_ERR_MISSING if the property is not found,
793 * or -FDT_ERR_BADLAYOUT if not enough data
795 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
796 u8 *array, int count);
799 * Look up a property in a node and return a pointer to its contents as a
800 * byte array of given length. The property must have at least enough data
801 * for the array (count bytes). It may have more, but this will be ignored.
802 * The data is not copied.
804 * @param blob FDT blob
805 * @param node node to examine
806 * @param prop_name name of property to find
807 * @param count number of array elements
808 * @return pointer to byte array if found, or NULL if the property is not
809 * found or there is not enough data
811 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
812 const char *prop_name, int count);
815 * Obtain an indexed resource from a device property.
817 * @param fdt FDT blob
818 * @param node node to examine
819 * @param property name of the property to parse
820 * @param index index of the resource to retrieve
821 * @param res returns the resource
822 * @return 0 if ok, negative on error
824 int fdt_get_resource(const void *fdt, int node, const char *property,
825 unsigned int index, struct fdt_resource *res);
828 * Obtain a named resource from a device property.
830 * Look up the index of the name in a list of strings and return the resource
833 * @param fdt FDT blob
834 * @param node node to examine
835 * @param property name of the property to parse
836 * @param prop_names name of the property containing the list of names
837 * @param name the name of the entry to look up
838 * @param res returns the resource
840 int fdt_get_named_resource(const void *fdt, int node, const char *property,
841 const char *prop_names, const char *name,
842 struct fdt_resource *res);
844 /* Display timings from linux include/video/display_timing.h */
846 DISPLAY_FLAGS_HSYNC_LOW = 1 << 0,
847 DISPLAY_FLAGS_HSYNC_HIGH = 1 << 1,
848 DISPLAY_FLAGS_VSYNC_LOW = 1 << 2,
849 DISPLAY_FLAGS_VSYNC_HIGH = 1 << 3,
851 /* data enable flag */
852 DISPLAY_FLAGS_DE_LOW = 1 << 4,
853 DISPLAY_FLAGS_DE_HIGH = 1 << 5,
854 /* drive data on pos. edge */
855 DISPLAY_FLAGS_PIXDATA_POSEDGE = 1 << 6,
856 /* drive data on neg. edge */
857 DISPLAY_FLAGS_PIXDATA_NEGEDGE = 1 << 7,
858 DISPLAY_FLAGS_INTERLACED = 1 << 8,
859 DISPLAY_FLAGS_DOUBLESCAN = 1 << 9,
860 DISPLAY_FLAGS_DOUBLECLK = 1 << 10,
864 * A single signal can be specified via a range of minimal and maximal values
865 * with a typical value, that lies somewhere inbetween.
867 struct timing_entry {
874 * Single "mode" entry. This describes one set of signal timings a display can
875 * have in one setting. This struct can later be converted to struct videomode
876 * (see include/video/videomode.h). As each timing_entry can be defined as a
877 * range, one struct display_timing may become multiple struct videomodes.
879 * Example: hsync active high, vsync active low
882 * Video ______________________XXXXXXXXXXXXXXXXXXXXXX_____________________
883 * |<- sync ->|<- back ->|<----- active ----->|<- front ->|<- sync..
884 * | | porch | | porch |
886 * HSync _|¯¯¯¯¯¯¯¯¯¯|___________________________________________|¯¯¯¯¯¯¯¯¯
888 * VSync ¯|__________|¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯|_________
890 struct display_timing {
891 struct timing_entry pixelclock;
893 struct timing_entry hactive; /* hor. active video */
894 struct timing_entry hfront_porch; /* hor. front porch */
895 struct timing_entry hback_porch; /* hor. back porch */
896 struct timing_entry hsync_len; /* hor. sync len */
898 struct timing_entry vactive; /* ver. active video */
899 struct timing_entry vfront_porch; /* ver. front porch */
900 struct timing_entry vback_porch; /* ver. back porch */
901 struct timing_entry vsync_len; /* ver. sync len */
903 enum display_flags flags; /* display flags */
904 bool hdmi_monitor; /* is hdmi monitor? */
908 * fdtdec_decode_display_timing() - decode display timings
910 * Decode display timings from the supplied 'display-timings' node.
911 * See doc/device-tree-bindings/video/display-timing.txt for binding
914 * @param blob FDT blob
915 * @param node 'display-timing' node containing the timing subnodes
916 * @param index Index number to read (0=first timing subnode)
917 * @param config Place to put timings
918 * @return 0 if OK, -FDT_ERR_NOTFOUND if not found
920 int fdtdec_decode_display_timing(const void *blob, int node, int index,
921 struct display_timing *config);
924 * fdtdec_setup_mem_size_base() - decode and setup gd->ram_size and
927 * Decode the /memory 'reg' property to determine the size and start of the
928 * first memory bank, populate the global data with the size and start of the
929 * first bank of memory.
931 * This function should be called from a boards dram_init(). This helper
932 * function allows for boards to query the device tree for DRAM size and start
933 * address instead of hard coding the value in the case where the memory size
934 * and start address cannot be detected automatically.
936 * @return 0 if OK, -EINVAL if the /memory node or reg property is missing or
939 int fdtdec_setup_mem_size_base(void);
942 * fdtdec_setup_mem_size_base_lowest() - decode and setup gd->ram_size and
943 * gd->ram_start by lowest available memory base
945 * Decode the /memory 'reg' property to determine the lowest start of the memory
946 * bank bank and populate the global data with it.
948 * This function should be called from a boards dram_init(). This helper
949 * function allows for boards to query the device tree for DRAM size and start
950 * address instead of hard coding the value in the case where the memory size
951 * and start address cannot be detected automatically.
953 * @return 0 if OK, -EINVAL if the /memory node or reg property is missing or
956 int fdtdec_setup_mem_size_base_lowest(void);
959 * fdtdec_setup_memory_banksize() - decode and populate gd->bd->bi_dram
961 * Decode the /memory 'reg' property to determine the address and size of the
962 * memory banks. Use this data to populate the global data board info with the
963 * phys address and size of memory banks.
965 * This function should be called from a boards dram_init_banksize(). This
966 * helper function allows for boards to query the device tree for memory bank
967 * information instead of hard coding the information in cases where it cannot
968 * be detected automatically.
970 * @return 0 if OK, -EINVAL if the /memory node or reg property is missing or
973 int fdtdec_setup_memory_banksize(void);
976 * fdtdec_set_ethernet_mac_address() - set MAC address for default interface
978 * Looks up the default interface via the "ethernet" alias (in the /aliases
979 * node) and stores the given MAC in its "local-mac-address" property. This
980 * is useful on platforms that store the MAC address in a custom location.
981 * Board code can call this in the late init stage to make sure that the
982 * interface device tree node has the right MAC address configured for the
983 * Ethernet uclass to pick it up.
985 * Typically the FDT passed into this function will be U-Boot's control DTB.
986 * Given that a lot of code may be holding offsets to various nodes in that
987 * tree, this code will only set the "local-mac-address" property in-place,
988 * which means that it needs to exist and have space for the 6-byte address.
989 * This ensures that the operation is non-destructive and does not invalidate
990 * offsets that other drivers may be using.
992 * @param fdt FDT blob
993 * @param mac buffer containing the MAC address to set
994 * @param size size of MAC address
995 * @return 0 on success or a negative error code on failure
997 int fdtdec_set_ethernet_mac_address(void *fdt, const u8 *mac, size_t size);
1000 * fdtdec_set_phandle() - sets the phandle of a given node
1002 * @param blob FDT blob
1003 * @param node offset in the FDT blob of the node whose phandle is to
1005 * @param phandle phandle to set for the given node
1006 * @return 0 on success or a negative error code on failure
1008 static inline int fdtdec_set_phandle(void *blob, int node, uint32_t phandle)
1010 return fdt_setprop_u32(blob, node, "phandle", phandle);
1014 * fdtdec_add_reserved_memory() - add or find a reserved-memory node
1016 * If a reserved-memory node already exists for the given carveout, a phandle
1017 * for that node will be returned. Otherwise a new node will be created and a
1018 * phandle corresponding to it will be returned.
1020 * See Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt
1021 * for details on how to use reserved memory regions.
1023 * As an example, consider the following code snippet:
1025 * struct fdt_memory fb = {
1026 * .start = 0x92cb3000,
1027 * .end = 0x934b2fff,
1031 * fdtdec_add_reserved_memory(fdt, "framebuffer", &fb, &phandle, false);
1033 * This results in the following subnode being added to the top-level
1034 * /reserved-memory node:
1037 * #address-cells = <0x00000002>;
1038 * #size-cells = <0x00000002>;
1041 * framebuffer@92cb3000 {
1042 * reg = <0x00000000 0x92cb3000 0x00000000 0x00800000>;
1043 * phandle = <0x0000004d>;
1047 * If the top-level /reserved-memory node does not exist, it will be created.
1048 * The phandle returned from the function call can be used to reference this
1049 * reserved memory region from other nodes.
1051 * See fdtdec_set_carveout() for a more elaborate example.
1053 * @param blob FDT blob
1054 * @param basename base name of the node to create
1055 * @param carveout information about the carveout region
1056 * @param phandlep return location for the phandle of the carveout region
1057 * can be NULL if no phandle should be added
1058 * @param no_map add "no-map" property if true
1059 * @return 0 on success or a negative error code on failure
1061 int fdtdec_add_reserved_memory(void *blob, const char *basename,
1062 const struct fdt_memory *carveout,
1063 uint32_t *phandlep, bool no_map);
1066 * fdtdec_get_carveout() - reads a carveout from an FDT
1068 * Reads information about a carveout region from an FDT. The carveout is a
1069 * referenced by its phandle that is read from a given property in a given
1072 * @param blob FDT blob
1073 * @param node name of a node
1074 * @param name name of the property in the given node that contains
1075 * the phandle for the carveout
1076 * @param index index of the phandle for which to read the carveout
1077 * @param carveout return location for the carveout information
1078 * @return 0 on success or a negative error code on failure
1080 int fdtdec_get_carveout(const void *blob, const char *node, const char *name,
1081 unsigned int index, struct fdt_memory *carveout);
1084 * fdtdec_set_carveout() - sets a carveout region for a given node
1086 * Sets a carveout region for a given node. If a reserved-memory node already
1087 * exists for the carveout, the phandle for that node will be reused. If no
1088 * such node exists, a new one will be created and a phandle to it stored in
1089 * a specified property of the given node.
1091 * As an example, consider the following code snippet:
1093 * const char *node = "/host1x@50000000/dc@54240000";
1094 * struct fdt_memory fb = {
1095 * .start = 0x92cb3000,
1096 * .end = 0x934b2fff,
1099 * fdtdec_set_carveout(fdt, node, "memory-region", 0, "framebuffer", &fb);
1101 * dc@54200000 is a display controller and was set up by the bootloader to
1102 * scan out the framebuffer specified by "fb". This would cause the following
1103 * reserved memory region to be added:
1106 * #address-cells = <0x00000002>;
1107 * #size-cells = <0x00000002>;
1110 * framebuffer@92cb3000 {
1111 * reg = <0x00000000 0x92cb3000 0x00000000 0x00800000>;
1112 * phandle = <0x0000004d>;
1116 * A "memory-region" property will also be added to the node referenced by the
1124 * memory-region = <0x0000004d>;
1131 * @param blob FDT blob
1132 * @param node name of the node to add the carveout to
1133 * @param prop_name name of the property in which to store the phandle of
1135 * @param index index of the phandle to store
1136 * @param name base name of the reserved-memory node to create
1137 * @param carveout information about the carveout to add
1138 * @return 0 on success or a negative error code on failure
1140 int fdtdec_set_carveout(void *blob, const char *node, const char *prop_name,
1141 unsigned int index, const char *name,
1142 const struct fdt_memory *carveout);
1145 * Set up the device tree ready for use
1147 int fdtdec_setup(void);
1150 * Perform board-specific early DT adjustments
1152 int fdtdec_board_setup(const void *fdt_blob);
1154 #if CONFIG_IS_ENABLED(MULTI_DTB_FIT)
1156 * fdtdec_resetup() - Set up the device tree again
1158 * The main difference with fdtdec_setup() is that it returns if the fdt has
1159 * changed because a better match has been found.
1160 * This is typically used for boards that rely on a DM driver to detect the
1161 * board type. This function sould be called by the board code after the stuff
1162 * needed by board_fit_config_name_match() to operate porperly is available.
1163 * If this functions signals that a rescan is necessary, the board code must
1164 * unbind all the drivers using dm_uninit() and then rescan the DT with
1165 * dm_init_and_scan().
1167 * @param rescan Returns a flag indicating that fdt has changed and rescanning
1168 * the fdt is required
1170 * @return 0 if OK, -ve on error
1172 int fdtdec_resetup(int *rescan);
1176 * Board-specific FDT initialization. Returns the address to a device tree blob.
1177 * Called when CONFIG_OF_BOARD is defined, or if CONFIG_OF_SEPARATE is defined
1178 * and the board implements it.
1180 void *board_fdt_blob_setup(void);
1183 * Decode the size of memory
1185 * RAM size is normally set in a /memory node and consists of a list of
1186 * (base, size) cells in the 'reg' property. This information is used to
1187 * determine the total available memory as well as the address and size
1190 * Optionally the memory configuration can vary depending on a board id,
1191 * typically read from strapping resistors or an EEPROM on the board.
1193 * Finally, memory size can be detected (within certain limits) by probing
1194 * the available memory. It is safe to do so within the limits provides by
1195 * the board's device tree information. This makes it possible to produce
1196 * boards with different memory sizes, where the device tree specifies the
1197 * maximum memory configuration, and the smaller memory configuration is
1200 * This function decodes that information, returning the memory base address,
1201 * size and bank information. See the memory.txt binding for full
1204 * @param blob Device tree blob
1205 * @param area Name of node to check (NULL means "/memory")
1206 * @param board_id Board ID to look up
1207 * @param basep Returns base address of first memory bank (NULL to
1209 * @param sizep Returns total memory size (NULL to ignore)
1210 * @param bd Updated with the memory bank information (NULL to skip)
1211 * @return 0 if OK, -ve on error
1213 int fdtdec_decode_ram_size(const void *blob, const char *area, int board_id,
1214 phys_addr_t *basep, phys_size_t *sizep,
1215 struct bd_info *bd);