2 * Copyright (c) 2011 The Chromium OS Authors.
3 * SPDX-License-Identifier: GPL-2.0+
10 * This file contains convenience functions for decoding useful and
11 * enlightening information from FDTs. It is intended to be used by device
12 * drivers and board-specific code within U-Boot. It aims to reduce the
13 * amount of FDT munging required within U-Boot itself, so that driver code
14 * changes to support FDT are minimized.
21 * A typedef for a physical address. Note that fdt data is always big
22 * endian even on a litle endian machine.
24 typedef phys_addr_t fdt_addr_t;
25 typedef phys_size_t fdt_size_t;
26 #ifdef CONFIG_PHYS_64BIT
27 #define FDT_ADDR_T_NONE (-1ULL)
28 #define fdt_addr_to_cpu(reg) be64_to_cpu(reg)
29 #define fdt_size_to_cpu(reg) be64_to_cpu(reg)
31 #define FDT_ADDR_T_NONE (-1U)
32 #define fdt_addr_to_cpu(reg) be32_to_cpu(reg)
33 #define fdt_size_to_cpu(reg) be32_to_cpu(reg)
36 /* Information obtained about memory from the FDT */
42 #ifdef CONFIG_SPL_BUILD
49 * Information about a resource. start is the first address of the resource
50 * and end is the last address (inclusive). The length of the resource will
51 * be equal to: end - start + 1.
59 FDT_PCI_SPACE_CONFIG = 0,
60 FDT_PCI_SPACE_IO = 0x01000000,
61 FDT_PCI_SPACE_MEM32 = 0x02000000,
62 FDT_PCI_SPACE_MEM64 = 0x03000000,
63 FDT_PCI_SPACE_MEM32_PREF = 0x42000000,
64 FDT_PCI_SPACE_MEM64_PREF = 0x43000000,
67 #define FDT_PCI_ADDR_CELLS 3
68 #define FDT_PCI_SIZE_CELLS 2
69 #define FDT_PCI_REG_SIZE \
70 ((FDT_PCI_ADDR_CELLS + FDT_PCI_SIZE_CELLS) * sizeof(u32))
73 * The Open Firmware spec defines PCI physical address as follows:
75 * bits# 31 .... 24 23 .... 16 15 .... 08 07 .... 00
77 * phys.hi cell: npt000ss bbbbbbbb dddddfff rrrrrrrr
78 * phys.mid cell: hhhhhhhh hhhhhhhh hhhhhhhh hhhhhhhh
79 * phys.lo cell: llllllll llllllll llllllll llllllll
83 * n: is 0 if the address is relocatable, 1 otherwise
84 * p: is 1 if addressable region is prefetchable, 0 otherwise
85 * t: is 1 if the address is aliased (for non-relocatable I/O) below 1MB
86 * (for Memory), or below 64KB (for relocatable I/O)
87 * ss: is the space code, denoting the address space
88 * bbbbbbbb: is the 8-bit Bus Number
89 * ddddd: is the 5-bit Device Number
90 * fff: is the 3-bit Function Number
91 * rrrrrrrr: is the 8-bit Register Number
92 * hhhhhhhh: is a 32-bit unsigned number
93 * llllllll: is a 32-bit unsigned number
102 * Compute the size of a resource.
104 * @param res the resource to operate on
105 * @return the size of the resource
107 static inline fdt_size_t fdt_resource_size(const struct fdt_resource *res)
109 return res->end - res->start + 1;
113 * Compat types that we know about and for which we might have drivers.
114 * Each is named COMPAT_<dir>_<filename> where <dir> is the directory
119 COMPAT_NVIDIA_TEGRA20_EMC, /* Tegra20 memory controller */
120 COMPAT_NVIDIA_TEGRA20_EMC_TABLE, /* Tegra20 memory timing table */
121 COMPAT_NVIDIA_TEGRA20_NAND, /* Tegra2 NAND controller */
122 COMPAT_NVIDIA_TEGRA124_PMC, /* Tegra 124 power mgmt controller */
123 COMPAT_NVIDIA_TEGRA186_SDMMC, /* Tegra186 SDMMC controller */
124 COMPAT_NVIDIA_TEGRA210_SDMMC, /* Tegra210 SDMMC controller */
125 COMPAT_NVIDIA_TEGRA124_SDMMC, /* Tegra124 SDMMC controller */
126 COMPAT_NVIDIA_TEGRA30_SDMMC, /* Tegra30 SDMMC controller */
127 COMPAT_NVIDIA_TEGRA20_SDMMC, /* Tegra20 SDMMC controller */
128 COMPAT_NVIDIA_TEGRA124_XUSB_PADCTL,
129 /* Tegra124 XUSB pad controller */
130 COMPAT_NVIDIA_TEGRA210_XUSB_PADCTL,
131 /* Tegra210 XUSB pad controller */
132 COMPAT_SMSC_LAN9215, /* SMSC 10/100 Ethernet LAN9215 */
133 COMPAT_SAMSUNG_EXYNOS5_SROMC, /* Exynos5 SROMC */
134 COMPAT_SAMSUNG_S3C2440_I2C, /* Exynos I2C Controller */
135 COMPAT_SAMSUNG_EXYNOS5_SOUND, /* Exynos Sound */
136 COMPAT_WOLFSON_WM8994_CODEC, /* Wolfson WM8994 Sound Codec */
137 COMPAT_SAMSUNG_EXYNOS_USB_PHY, /* Exynos phy controller for usb2.0 */
138 COMPAT_SAMSUNG_EXYNOS5_USB3_PHY,/* Exynos phy controller for usb3.0 */
139 COMPAT_SAMSUNG_EXYNOS_TMU, /* Exynos TMU */
140 COMPAT_SAMSUNG_EXYNOS_MIPI_DSI, /* Exynos mipi dsi */
141 COMPAT_SAMSUNG_EXYNOS_DWMMC, /* Exynos DWMMC controller */
142 COMPAT_SAMSUNG_EXYNOS_MMC, /* Exynos MMC controller */
143 COMPAT_MAXIM_MAX77686_PMIC, /* MAX77686 PMIC */
144 COMPAT_GENERIC_SPI_FLASH, /* Generic SPI Flash chip */
145 COMPAT_MAXIM_98095_CODEC, /* MAX98095 Codec */
146 COMPAT_SAMSUNG_EXYNOS5_I2C, /* Exynos5 High Speed I2C Controller */
147 COMPAT_SAMSUNG_EXYNOS_SYSMMU, /* Exynos sysmmu */
148 COMPAT_INTEL_MICROCODE, /* Intel microcode update */
149 COMPAT_AMS_AS3722, /* AMS AS3722 PMIC */
150 COMPAT_INTEL_QRK_MRC, /* Intel Quark MRC */
151 COMPAT_ALTERA_SOCFPGA_DWMAC, /* SoCFPGA Ethernet controller */
152 COMPAT_ALTERA_SOCFPGA_DWMMC, /* SoCFPGA DWMMC controller */
153 COMPAT_ALTERA_SOCFPGA_DWC2USB, /* SoCFPGA DWC2 USB controller */
154 COMPAT_INTEL_BAYTRAIL_FSP, /* Intel Bay Trail FSP */
155 COMPAT_INTEL_BAYTRAIL_FSP_MDP, /* Intel FSP memory-down params */
156 COMPAT_INTEL_IVYBRIDGE_FSP, /* Intel Ivy Bridge FSP */
157 COMPAT_SUNXI_NAND, /* SUNXI NAND controller */
158 COMPAT_ALTERA_SOCFPGA_CLK, /* SoCFPGA Clock initialization */
159 COMPAT_ALTERA_SOCFPGA_PINCTRL_SINGLE, /* SoCFPGA pinctrl-single */
160 COMPAT_ALTERA_SOCFPGA_H2F_BRG, /* SoCFPGA hps2fpga bridge */
161 COMPAT_ALTERA_SOCFPGA_LWH2F_BRG, /* SoCFPGA lwhps2fpga bridge */
162 COMPAT_ALTERA_SOCFPGA_F2H_BRG, /* SoCFPGA fpga2hps bridge */
163 COMPAT_ALTERA_SOCFPGA_F2SDR0, /* SoCFPGA fpga2SDRAM0 bridge */
164 COMPAT_ALTERA_SOCFPGA_F2SDR1, /* SoCFPGA fpga2SDRAM1 bridge */
165 COMPAT_ALTERA_SOCFPGA_F2SDR2, /* SoCFPGA fpga2SDRAM2 bridge */
170 #define MAX_PHANDLE_ARGS 16
171 struct fdtdec_phandle_args {
174 uint32_t args[MAX_PHANDLE_ARGS];
178 * fdtdec_parse_phandle_with_args() - Find a node pointed by phandle in a list
180 * This function is useful to parse lists of phandles and their arguments.
193 * list = <&phandle1 1 2 &phandle2 3>;
196 * To get a device_node of the `node2' node you may call this:
197 * fdtdec_parse_phandle_with_args(blob, node3, "list", "#list-cells", 0, 1,
200 * (This function is a modified version of __of_parse_phandle_with_args() from
203 * @blob: Pointer to device tree
204 * @src_node: Offset of device tree node containing a list
205 * @list_name: property name that contains a list
206 * @cells_name: property name that specifies the phandles' arguments count,
207 * or NULL to use @cells_count
208 * @cells_count: Cell count to use if @cells_name is NULL
209 * @index: index of a phandle to parse out
210 * @out_args: optional pointer to output arguments structure (will be filled)
211 * @return 0 on success (with @out_args filled out if not NULL), -ENOENT if
212 * @list_name does not exist, a phandle was not found, @cells_name
213 * could not be found, the arguments were truncated or there were too
217 int fdtdec_parse_phandle_with_args(const void *blob, int src_node,
218 const char *list_name,
219 const char *cells_name,
220 int cell_count, int index,
221 struct fdtdec_phandle_args *out_args);
224 * Find the next numbered alias for a peripheral. This is used to enumerate
225 * all the peripherals of a certain type.
227 * Do the first call with *upto = 0. Assuming /aliases/<name>0 exists then
228 * this function will return a pointer to the node the alias points to, and
229 * then update *upto to 1. Next time you call this function, the next node
232 * All nodes returned will match the compatible ID, as it is assumed that
233 * all peripherals use the same driver.
235 * @param blob FDT blob to use
236 * @param name Root name of alias to search for
237 * @param id Compatible ID to look for
238 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
240 int fdtdec_next_alias(const void *blob, const char *name,
241 enum fdt_compat_id id, int *upto);
244 * Find the compatible ID for a given node.
246 * Generally each node has at least one compatible string attached to it.
247 * This function looks through our list of known compatible strings and
248 * returns the corresponding ID which matches the compatible string.
250 * @param blob FDT blob to use
251 * @param node Node containing compatible string to find
252 * @return compatible ID, or COMPAT_UNKNOWN if we cannot find a match
254 enum fdt_compat_id fdtdec_lookup(const void *blob, int node);
257 * Find the next compatible node for a peripheral.
259 * Do the first call with node = 0. This function will return a pointer to
260 * the next compatible node. Next time you call this function, pass the
261 * value returned, and the next node will be provided.
263 * @param blob FDT blob to use
264 * @param node Start node for search
265 * @param id Compatible ID to look for (enum fdt_compat_id)
266 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
268 int fdtdec_next_compatible(const void *blob, int node,
269 enum fdt_compat_id id);
272 * Find the next compatible subnode for a peripheral.
274 * Do the first call with node set to the parent and depth = 0. This
275 * function will return the offset of the next compatible node. Next time
276 * you call this function, pass the node value returned last time, with
277 * depth unchanged, and the next node will be provided.
279 * @param blob FDT blob to use
280 * @param node Start node for search
281 * @param id Compatible ID to look for (enum fdt_compat_id)
282 * @param depthp Current depth (set to 0 before first call)
283 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
285 int fdtdec_next_compatible_subnode(const void *blob, int node,
286 enum fdt_compat_id id, int *depthp);
289 * Look up an address property in a node and return the parsed address, and
290 * optionally the parsed size.
292 * This variant assumes a known and fixed number of cells are used to
293 * represent the address and size.
295 * You probably don't want to use this function directly except to parse
296 * non-standard properties, and never to parse the "reg" property. Instead,
297 * use one of the "auto" variants below, which automatically honor the
298 * #address-cells and #size-cells properties in the parent node.
300 * @param blob FDT blob
301 * @param node node to examine
302 * @param prop_name name of property to find
303 * @param index which address to retrieve from a list of addresses. Often 0.
304 * @param na the number of cells used to represent an address
305 * @param ns the number of cells used to represent a size
306 * @param sizep a pointer to store the size into. Use NULL if not required
307 * @param translate Indicates whether to translate the returned value
308 * using the parent node's ranges property.
309 * @return address, if found, or FDT_ADDR_T_NONE if not
311 fdt_addr_t fdtdec_get_addr_size_fixed(const void *blob, int node,
312 const char *prop_name, int index, int na, int ns,
313 fdt_size_t *sizep, bool translate);
316 * Look up an address property in a node and return the parsed address, and
317 * optionally the parsed size.
319 * This variant automatically determines the number of cells used to represent
320 * the address and size by parsing the provided parent node's #address-cells
321 * and #size-cells properties.
323 * @param blob FDT blob
324 * @param parent parent node of @node
325 * @param node node to examine
326 * @param prop_name name of property to find
327 * @param index which address to retrieve from a list of addresses. Often 0.
328 * @param sizep a pointer to store the size into. Use NULL if not required
329 * @param translate Indicates whether to translate the returned value
330 * using the parent node's ranges property.
331 * @return address, if found, or FDT_ADDR_T_NONE if not
333 fdt_addr_t fdtdec_get_addr_size_auto_parent(const void *blob, int parent,
334 int node, const char *prop_name, int index, fdt_size_t *sizep,
338 * Look up an address property in a node and return the parsed address, and
339 * optionally the parsed size.
341 * This variant automatically determines the number of cells used to represent
342 * the address and size by parsing the parent node's #address-cells
343 * and #size-cells properties. The parent node is automatically found.
345 * The automatic parent lookup implemented by this function is slow.
346 * Consequently, fdtdec_get_addr_size_auto_parent() should be used where
349 * @param blob FDT blob
350 * @param parent parent node of @node
351 * @param node node to examine
352 * @param prop_name name of property to find
353 * @param index which address to retrieve from a list of addresses. Often 0.
354 * @param sizep a pointer to store the size into. Use NULL if not required
355 * @param translate Indicates whether to translate the returned value
356 * using the parent node's ranges property.
357 * @return address, if found, or FDT_ADDR_T_NONE if not
359 fdt_addr_t fdtdec_get_addr_size_auto_noparent(const void *blob, int node,
360 const char *prop_name, int index, fdt_size_t *sizep,
364 * Look up an address property in a node and return the parsed address.
366 * This variant hard-codes the number of cells used to represent the address
367 * and size based on sizeof(fdt_addr_t) and sizeof(fdt_size_t). It also
368 * always returns the first address value in the property (index 0).
370 * Use of this function is not recommended due to the hard-coding of cell
371 * counts. There is no programmatic validation that these hard-coded values
372 * actually match the device tree content in any way at all. This assumption
373 * can be satisfied by manually ensuring CONFIG_PHYS_64BIT is appropriately
374 * set in the U-Boot build and exercising strict control over DT content to
375 * ensure use of matching #address-cells/#size-cells properties. However, this
376 * approach is error-prone; those familiar with DT will not expect the
377 * assumption to exist, and could easily invalidate it. If the assumption is
378 * invalidated, this function will not report the issue, and debugging will
379 * be required. Instead, use fdtdec_get_addr_size_auto_parent().
381 * @param blob FDT blob
382 * @param node node to examine
383 * @param prop_name name of property to find
384 * @return address, if found, or FDT_ADDR_T_NONE if not
386 fdt_addr_t fdtdec_get_addr(const void *blob, int node,
387 const char *prop_name);
390 * Look up an address property in a node and return the parsed address, and
391 * optionally the parsed size.
393 * This variant hard-codes the number of cells used to represent the address
394 * and size based on sizeof(fdt_addr_t) and sizeof(fdt_size_t). It also
395 * always returns the first address value in the property (index 0).
397 * Use of this function is not recommended due to the hard-coding of cell
398 * counts. There is no programmatic validation that these hard-coded values
399 * actually match the device tree content in any way at all. This assumption
400 * can be satisfied by manually ensuring CONFIG_PHYS_64BIT is appropriately
401 * set in the U-Boot build and exercising strict control over DT content to
402 * ensure use of matching #address-cells/#size-cells properties. However, this
403 * approach is error-prone; those familiar with DT will not expect the
404 * assumption to exist, and could easily invalidate it. If the assumption is
405 * invalidated, this function will not report the issue, and debugging will
406 * be required. Instead, use fdtdec_get_addr_size_auto_parent().
408 * @param blob FDT blob
409 * @param node node to examine
410 * @param prop_name name of property to find
411 * @param sizep a pointer to store the size into. Use NULL if not required
412 * @return address, if found, or FDT_ADDR_T_NONE if not
414 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
415 const char *prop_name, fdt_size_t *sizep);
418 * Look at an address property in a node and return the pci address which
419 * corresponds to the given type in the form of fdt_pci_addr.
420 * The property must hold one fdt_pci_addr with a lengh.
422 * @param blob FDT blob
423 * @param node node to examine
424 * @param type pci address type (FDT_PCI_SPACE_xxx)
425 * @param prop_name name of property to find
426 * @param addr returns pci address in the form of fdt_pci_addr
427 * @return 0 if ok, -ENOENT if the property did not exist, -EINVAL if the
428 * format of the property was invalid, -ENXIO if the requested
429 * address type was not found
431 int fdtdec_get_pci_addr(const void *blob, int node, enum fdt_pci_space type,
432 const char *prop_name, struct fdt_pci_addr *addr);
435 * Look at the compatible property of a device node that represents a PCI
436 * device and extract pci vendor id and device id from it.
438 * @param blob FDT blob
439 * @param node node to examine
440 * @param vendor vendor id of the pci device
441 * @param device device id of the pci device
442 * @return 0 if ok, negative on error
444 int fdtdec_get_pci_vendev(const void *blob, int node,
445 u16 *vendor, u16 *device);
448 * Look at the pci address of a device node that represents a PCI device
449 * and return base address of the pci device's registers.
451 * @param dev device to examine
452 * @param addr pci address in the form of fdt_pci_addr
453 * @param bar returns base address of the pci device's registers
454 * @return 0 if ok, negative on error
456 int fdtdec_get_pci_bar32(struct udevice *dev, struct fdt_pci_addr *addr,
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 a property from the /chosen node
627 * @param blob Device tree blob (if NULL, then NULL is returned)
628 * @param name Property name to look up
629 * @return Value of property, or NULL if it does not exist
631 const char *fdtdec_get_chosen_prop(const void *blob, const char *name);
634 * Get the offset of the given /chosen node
636 * This looks up a property in /chosen containing the path to another node,
637 * then finds the offset of that node.
639 * @param blob Device tree blob (if NULL, then error is returned)
640 * @param name Property name, e.g. "stdout-path"
641 * @return Node offset referred to by that chosen node, or -ve FDT_ERR_...
643 int fdtdec_get_chosen_node(const void *blob, const char *name);
646 * Get the name for a compatible ID
648 * @param id Compatible ID to look for
649 * @return compatible string for that id
651 const char *fdtdec_get_compatible(enum fdt_compat_id id);
653 /* Look up a phandle and follow it to its node. Then return the offset
656 * @param blob FDT blob
657 * @param node node to examine
658 * @param prop_name name of property to find
659 * @return node offset if found, -ve error code on error
661 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name);
664 * Look up a property in a node and return its contents in an integer
665 * array of given length. The property must have at least enough data for
666 * the array (4*count bytes). It may have more, but this will be ignored.
668 * @param blob FDT blob
669 * @param node node to examine
670 * @param prop_name name of property to find
671 * @param array array to fill with data
672 * @param count number of array elements
673 * @return 0 if ok, or -FDT_ERR_NOTFOUND if the property is not found,
674 * or -FDT_ERR_BADLAYOUT if not enough data
676 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
677 u32 *array, int count);
680 * Look up a property in a node and return its contents in an integer
681 * array of given length. The property must exist but may have less data that
682 * expected (4*count bytes). It may have more, but this will be ignored.
684 * @param blob FDT blob
685 * @param node node to examine
686 * @param prop_name name of property to find
687 * @param array array to fill with data
688 * @param count number of array elements
689 * @return number of array elements if ok, or -FDT_ERR_NOTFOUND if the
690 * property is not found
692 int fdtdec_get_int_array_count(const void *blob, int node,
693 const char *prop_name, u32 *array, int count);
696 * Look up a property in a node and return a pointer to its contents as a
697 * unsigned int array of given length. The property must have at least enough
698 * data for the array ('count' cells). It may have more, but this will be
699 * ignored. The data is not copied.
701 * Note that you must access elements of the array with fdt32_to_cpu(),
702 * since the elements will be big endian even on a little endian machine.
704 * @param blob FDT blob
705 * @param node node to examine
706 * @param prop_name name of property to find
707 * @param count number of array elements
708 * @return pointer to array if found, or NULL if the property is not
709 * found or there is not enough data
711 const u32 *fdtdec_locate_array(const void *blob, int node,
712 const char *prop_name, int count);
715 * Look up a boolean property in a node and return it.
717 * A boolean properly is true if present in the device tree and false if not
718 * present, regardless of its value.
720 * @param blob FDT blob
721 * @param node node to examine
722 * @param prop_name name of property to find
723 * @return 1 if the properly is present; 0 if it isn't present
725 int fdtdec_get_bool(const void *blob, int node, const char *prop_name);
728 * Count child nodes of one parent node.
730 * @param blob FDT blob
731 * @param node parent node
732 * @return number of child node; 0 if there is not child node
734 int fdtdec_get_child_count(const void *blob, int node);
737 * Look in the FDT for a config item with the given name and return its value
738 * as a 32-bit integer. The property must have at least 4 bytes of data. The
739 * value of the first cell is returned.
741 * @param blob FDT blob to use
742 * @param prop_name Node property name
743 * @param default_val default value to return if the property is not found
744 * @return integer value, if found, or default_val if not
746 int fdtdec_get_config_int(const void *blob, const char *prop_name,
750 * Look in the FDT for a config item with the given name
751 * and return whether it exists.
753 * @param blob FDT blob
754 * @param prop_name property name to look up
755 * @return 1, if it exists, or 0 if not
757 int fdtdec_get_config_bool(const void *blob, const char *prop_name);
760 * Look in the FDT for a config item with the given name and return its value
763 * @param blob FDT blob
764 * @param prop_name property name to look up
765 * @returns property string, NULL on error.
767 char *fdtdec_get_config_string(const void *blob, const char *prop_name);
770 * Look up a property in a node and return its contents in a byte
771 * array of given length. The property must have at least enough data for
772 * the array (count bytes). It may have more, but this will be ignored.
774 * @param blob FDT blob
775 * @param node node to examine
776 * @param prop_name name of property to find
777 * @param array array to fill with data
778 * @param count number of array elements
779 * @return 0 if ok, or -FDT_ERR_MISSING if the property is not found,
780 * or -FDT_ERR_BADLAYOUT if not enough data
782 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
783 u8 *array, int count);
786 * Look up a property in a node and return a pointer to its contents as a
787 * byte array of given length. The property must have at least enough data
788 * for the array (count bytes). It may have more, but this will be ignored.
789 * The data is not copied.
791 * @param blob FDT blob
792 * @param node node to examine
793 * @param prop_name name of property to find
794 * @param count number of array elements
795 * @return pointer to byte array if found, or NULL if the property is not
796 * found or there is not enough data
798 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
799 const char *prop_name, int count);
802 * Look up a property in a node which contains a memory region address and
803 * size. Then return a pointer to this address.
805 * The property must hold one address with a length. This is only tested on
808 * @param blob FDT blob
809 * @param node node to examine
810 * @param prop_name name of property to find
811 * @param basep Returns base address of region
812 * @param size Returns size of region
813 * @return 0 if ok, -1 on error (property not found)
815 int fdtdec_decode_region(const void *blob, int node, const char *prop_name,
816 fdt_addr_t *basep, fdt_size_t *sizep);
818 enum fmap_compress_t {
829 /* A flash map entry, containing an offset and length */
833 uint32_t used; /* Number of bytes used in region */
834 enum fmap_compress_t compress_algo; /* Compression type */
835 enum fmap_hash_t hash_algo; /* Hash algorithm */
836 const uint8_t *hash; /* Hash value */
837 int hash_size; /* Hash size */
841 * Read a flash entry from the fdt
843 * @param blob FDT blob
844 * @param node Offset of node to read
845 * @param name Name of node being read
846 * @param entry Place to put offset and size of this node
847 * @return 0 if ok, -ve on error
849 int fdtdec_read_fmap_entry(const void *blob, int node, const char *name,
850 struct fmap_entry *entry);
853 * Obtain an indexed resource from a device property.
855 * @param fdt FDT blob
856 * @param node node to examine
857 * @param property name of the property to parse
858 * @param index index of the resource to retrieve
859 * @param res returns the resource
860 * @return 0 if ok, negative on error
862 int fdt_get_resource(const void *fdt, int node, const char *property,
863 unsigned int index, struct fdt_resource *res);
866 * Obtain a named resource from a device property.
868 * Look up the index of the name in a list of strings and return the resource
871 * @param fdt FDT blob
872 * @param node node to examine
873 * @param property name of the property to parse
874 * @param prop_names name of the property containing the list of names
875 * @param name the name of the entry to look up
876 * @param res returns the resource
878 int fdt_get_named_resource(const void *fdt, int node, const char *property,
879 const char *prop_names, const char *name,
880 struct fdt_resource *res);
883 * Decode a named region within a memory bank of a given type.
885 * This function handles selection of a memory region. The region is
886 * specified as an offset/size within a particular type of memory.
888 * The properties used are:
890 * <mem_type>-memory<suffix> for the name of the memory bank
891 * <mem_type>-offset<suffix> for the offset in that bank
893 * The property value must have an offset and a size. The function checks
894 * that the region is entirely within the memory bank.5
896 * @param blob FDT blob
897 * @param node Node containing the properties (-1 for /config)
898 * @param mem_type Type of memory to use, which is a name, such as
899 * "u-boot" or "kernel".
900 * @param suffix String to append to the memory/offset
902 * @param basep Returns base of region
903 * @param sizep Returns size of region
904 * @return 0 if OK, -ive on error
906 int fdtdec_decode_memory_region(const void *blob, int node,
907 const char *mem_type, const char *suffix,
908 fdt_addr_t *basep, fdt_size_t *sizep);
910 /* Display timings from linux include/video/display_timing.h */
912 DISPLAY_FLAGS_HSYNC_LOW = 1 << 0,
913 DISPLAY_FLAGS_HSYNC_HIGH = 1 << 1,
914 DISPLAY_FLAGS_VSYNC_LOW = 1 << 2,
915 DISPLAY_FLAGS_VSYNC_HIGH = 1 << 3,
917 /* data enable flag */
918 DISPLAY_FLAGS_DE_LOW = 1 << 4,
919 DISPLAY_FLAGS_DE_HIGH = 1 << 5,
920 /* drive data on pos. edge */
921 DISPLAY_FLAGS_PIXDATA_POSEDGE = 1 << 6,
922 /* drive data on neg. edge */
923 DISPLAY_FLAGS_PIXDATA_NEGEDGE = 1 << 7,
924 DISPLAY_FLAGS_INTERLACED = 1 << 8,
925 DISPLAY_FLAGS_DOUBLESCAN = 1 << 9,
926 DISPLAY_FLAGS_DOUBLECLK = 1 << 10,
930 * A single signal can be specified via a range of minimal and maximal values
931 * with a typical value, that lies somewhere inbetween.
933 struct timing_entry {
940 * Single "mode" entry. This describes one set of signal timings a display can
941 * have in one setting. This struct can later be converted to struct videomode
942 * (see include/video/videomode.h). As each timing_entry can be defined as a
943 * range, one struct display_timing may become multiple struct videomodes.
945 * Example: hsync active high, vsync active low
948 * Video ______________________XXXXXXXXXXXXXXXXXXXXXX_____________________
949 * |<- sync ->|<- back ->|<----- active ----->|<- front ->|<- sync..
950 * | | porch | | porch |
952 * HSync _|¯¯¯¯¯¯¯¯¯¯|___________________________________________|¯¯¯¯¯¯¯¯¯
954 * VSync ¯|__________|¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯|_________
956 struct display_timing {
957 struct timing_entry pixelclock;
959 struct timing_entry hactive; /* hor. active video */
960 struct timing_entry hfront_porch; /* hor. front porch */
961 struct timing_entry hback_porch; /* hor. back porch */
962 struct timing_entry hsync_len; /* hor. sync len */
964 struct timing_entry vactive; /* ver. active video */
965 struct timing_entry vfront_porch; /* ver. front porch */
966 struct timing_entry vback_porch; /* ver. back porch */
967 struct timing_entry vsync_len; /* ver. sync len */
969 enum display_flags flags; /* display flags */
970 bool hdmi_monitor; /* is hdmi monitor? */
974 * fdtdec_decode_display_timing() - decode display timings
976 * Decode display timings from the supplied 'display-timings' node.
977 * See doc/device-tree-bindings/video/display-timing.txt for binding
980 * @param blob FDT blob
981 * @param node 'display-timing' node containing the timing subnodes
982 * @param index Index number to read (0=first timing subnode)
983 * @param config Place to put timings
984 * @return 0 if OK, -FDT_ERR_NOTFOUND if not found
986 int fdtdec_decode_display_timing(const void *blob, int node, int index,
987 struct display_timing *config);
990 * fdtdec_setup_memory_size() - decode and setup gd->ram_size
992 * Decode the /memory 'reg' property to determine the size of the first memory
993 * bank, populate the global data with the size of the first bank of memory.
995 * This function should be called from a boards dram_init(). This helper
996 * function allows for boards to query the device tree for DRAM size instead of
997 * hard coding the value in the case where the memory size cannot be detected
1000 * @return 0 if OK, -EINVAL if the /memory node or reg property is missing or
1003 int fdtdec_setup_memory_size(void);
1006 * fdtdec_setup_memory_banksize() - decode and populate gd->bd->bi_dram
1008 * Decode the /memory 'reg' property to determine the address and size of the
1009 * memory banks. Use this data to populate the global data board info with the
1010 * phys address and size of memory banks.
1012 * This function should be called from a boards dram_init_banksize(). This
1013 * helper function allows for boards to query the device tree for memory bank
1014 * information instead of hard coding the information in cases where it cannot
1015 * be detected automatically.
1017 * @return 0 if OK, -EINVAL if the /memory node or reg property is missing or
1020 int fdtdec_setup_memory_banksize(void);
1023 * Set up the device tree ready for use
1025 int fdtdec_setup(void);
1028 * Board-specific FDT initialization. Returns the address to a device tree blob.
1029 * Called when CONFIG_OF_BOARD is defined.
1031 void *board_fdt_blob_setup(void);