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;
26 #ifdef CONFIG_PHYS_64BIT
27 #define FDT_ADDR_T_NONE (-1U)
28 #define fdt_addr_to_cpu(reg) be64_to_cpu(reg)
29 #define fdt_size_to_cpu(reg) be64_to_cpu(reg)
30 #define cpu_to_fdt_addr(reg) cpu_to_be64(reg)
31 #define cpu_to_fdt_size(reg) cpu_to_be64(reg)
32 typedef fdt64_t fdt_val_t;
34 #define FDT_ADDR_T_NONE (-1U)
35 #define fdt_addr_to_cpu(reg) be32_to_cpu(reg)
36 #define fdt_size_to_cpu(reg) be32_to_cpu(reg)
37 #define cpu_to_fdt_addr(reg) cpu_to_be32(reg)
38 #define cpu_to_fdt_size(reg) cpu_to_be32(reg)
39 typedef fdt32_t fdt_val_t;
42 /* Information obtained about memory from the FDT */
50 #ifdef CONFIG_SPL_BUILD
56 #if CONFIG_IS_ENABLED(OF_PRIOR_STAGE)
57 extern phys_addr_t prior_stage_fdt_address;
61 * Information about a resource. start is the first address of the resource
62 * and end is the last address (inclusive). The length of the resource will
63 * be equal to: end - start + 1.
71 FDT_PCI_SPACE_CONFIG = 0,
72 FDT_PCI_SPACE_IO = 0x01000000,
73 FDT_PCI_SPACE_MEM32 = 0x02000000,
74 FDT_PCI_SPACE_MEM64 = 0x03000000,
75 FDT_PCI_SPACE_MEM32_PREF = 0x42000000,
76 FDT_PCI_SPACE_MEM64_PREF = 0x43000000,
79 #define FDT_PCI_ADDR_CELLS 3
80 #define FDT_PCI_SIZE_CELLS 2
81 #define FDT_PCI_REG_SIZE \
82 ((FDT_PCI_ADDR_CELLS + FDT_PCI_SIZE_CELLS) * sizeof(u32))
85 * The Open Firmware spec defines PCI physical address as follows:
87 * bits# 31 .... 24 23 .... 16 15 .... 08 07 .... 00
89 * phys.hi cell: npt000ss bbbbbbbb dddddfff rrrrrrrr
90 * phys.mid cell: hhhhhhhh hhhhhhhh hhhhhhhh hhhhhhhh
91 * phys.lo cell: llllllll llllllll llllllll llllllll
95 * n: is 0 if the address is relocatable, 1 otherwise
96 * p: is 1 if addressable region is prefetchable, 0 otherwise
97 * t: is 1 if the address is aliased (for non-relocatable I/O) below 1MB
98 * (for Memory), or below 64KB (for relocatable I/O)
99 * ss: is the space code, denoting the address space
100 * bbbbbbbb: is the 8-bit Bus Number
101 * ddddd: is the 5-bit Device Number
102 * fff: is the 3-bit Function Number
103 * rrrrrrrr: is the 8-bit Register Number
104 * hhhhhhhh: is a 32-bit unsigned number
105 * llllllll: is a 32-bit unsigned number
107 struct fdt_pci_addr {
114 * Compute the size of a resource.
116 * @param res the resource to operate on
117 * @return the size of the resource
119 static inline fdt_size_t fdt_resource_size(const struct fdt_resource *res)
121 return res->end - res->start + 1;
125 * Compat types that we know about and for which we might have drivers.
126 * Each is named COMPAT_<dir>_<filename> where <dir> is the directory
131 COMPAT_NVIDIA_TEGRA20_EMC, /* Tegra20 memory controller */
132 COMPAT_NVIDIA_TEGRA20_EMC_TABLE, /* Tegra20 memory timing table */
133 COMPAT_NVIDIA_TEGRA20_NAND, /* Tegra2 NAND controller */
134 COMPAT_NVIDIA_TEGRA124_XUSB_PADCTL,
135 /* Tegra124 XUSB pad controller */
136 COMPAT_NVIDIA_TEGRA210_XUSB_PADCTL,
137 /* Tegra210 XUSB pad controller */
138 COMPAT_SMSC_LAN9215, /* SMSC 10/100 Ethernet LAN9215 */
139 COMPAT_SAMSUNG_EXYNOS5_SROMC, /* Exynos5 SROMC */
140 COMPAT_SAMSUNG_EXYNOS_USB_PHY, /* Exynos phy controller for usb2.0 */
141 COMPAT_SAMSUNG_EXYNOS5_USB3_PHY,/* Exynos phy controller for usb3.0 */
142 COMPAT_SAMSUNG_EXYNOS_TMU, /* Exynos TMU */
143 COMPAT_SAMSUNG_EXYNOS_MIPI_DSI, /* Exynos mipi dsi */
144 COMPAT_SAMSUNG_EXYNOS_DWMMC, /* Exynos DWMMC controller */
145 COMPAT_GENERIC_SPI_FLASH, /* Generic SPI Flash chip */
146 COMPAT_SAMSUNG_EXYNOS_SYSMMU, /* Exynos sysmmu */
147 COMPAT_INTEL_MICROCODE, /* Intel microcode update */
148 COMPAT_INTEL_QRK_MRC, /* Intel Quark MRC */
149 COMPAT_ALTERA_SOCFPGA_DWMAC, /* SoCFPGA Ethernet controller */
150 COMPAT_ALTERA_SOCFPGA_DWMMC, /* SoCFPGA DWMMC controller */
151 COMPAT_ALTERA_SOCFPGA_DWC2USB, /* SoCFPGA DWC2 USB controller */
152 COMPAT_INTEL_BAYTRAIL_FSP, /* Intel Bay Trail FSP */
153 COMPAT_INTEL_BAYTRAIL_FSP_MDP, /* Intel FSP memory-down params */
154 COMPAT_INTEL_IVYBRIDGE_FSP, /* Intel Ivy Bridge FSP */
155 COMPAT_SUNXI_NAND, /* SUNXI NAND controller */
156 COMPAT_ALTERA_SOCFPGA_CLK, /* SoCFPGA Clock initialization */
157 COMPAT_ALTERA_SOCFPGA_PINCTRL_SINGLE, /* SoCFPGA pinctrl-single */
158 COMPAT_ALTERA_SOCFPGA_H2F_BRG, /* SoCFPGA hps2fpga bridge */
159 COMPAT_ALTERA_SOCFPGA_LWH2F_BRG, /* SoCFPGA lwhps2fpga bridge */
160 COMPAT_ALTERA_SOCFPGA_F2H_BRG, /* SoCFPGA fpga2hps bridge */
161 COMPAT_ALTERA_SOCFPGA_F2SDR0, /* SoCFPGA fpga2SDRAM0 bridge */
162 COMPAT_ALTERA_SOCFPGA_F2SDR1, /* SoCFPGA fpga2SDRAM1 bridge */
163 COMPAT_ALTERA_SOCFPGA_F2SDR2, /* SoCFPGA fpga2SDRAM2 bridge */
164 COMPAT_ALTERA_SOCFPGA_FPGA0, /* SOCFPGA FPGA manager */
165 COMPAT_ALTERA_SOCFPGA_NOC, /* SOCFPGA Arria 10 NOC */
166 COMPAT_ALTERA_SOCFPGA_CLK_INIT, /* SOCFPGA Arria 10 clk init */
171 #define MAX_PHANDLE_ARGS 16
172 struct fdtdec_phandle_args {
175 uint32_t args[MAX_PHANDLE_ARGS];
179 * fdtdec_parse_phandle_with_args() - Find a node pointed by phandle in a list
181 * This function is useful to parse lists of phandles and their arguments.
194 * list = <&phandle1 1 2 &phandle2 3>;
197 * To get a device_node of the `node2' node you may call this:
198 * fdtdec_parse_phandle_with_args(blob, node3, "list", "#list-cells", 0, 1,
201 * (This function is a modified version of __of_parse_phandle_with_args() from
204 * @blob: Pointer to device tree
205 * @src_node: Offset of device tree node containing a list
206 * @list_name: property name that contains a list
207 * @cells_name: property name that specifies the phandles' arguments count,
208 * or NULL to use @cells_count
209 * @cells_count: Cell count to use if @cells_name is NULL
210 * @index: index of a phandle to parse out
211 * @out_args: optional pointer to output arguments structure (will be filled)
212 * @return 0 on success (with @out_args filled out if not NULL), -ENOENT if
213 * @list_name does not exist, a phandle was not found, @cells_name
214 * could not be found, the arguments were truncated or there were too
218 int fdtdec_parse_phandle_with_args(const void *blob, int src_node,
219 const char *list_name,
220 const char *cells_name,
221 int cell_count, int index,
222 struct fdtdec_phandle_args *out_args);
225 * Find the next numbered alias for a peripheral. This is used to enumerate
226 * all the peripherals of a certain type.
228 * Do the first call with *upto = 0. Assuming /aliases/<name>0 exists then
229 * this function will return a pointer to the node the alias points to, and
230 * then update *upto to 1. Next time you call this function, the next node
233 * All nodes returned will match the compatible ID, as it is assumed that
234 * all peripherals use the same driver.
236 * @param blob FDT blob to use
237 * @param name Root name of alias to search for
238 * @param id Compatible ID to look for
239 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
241 int fdtdec_next_alias(const void *blob, const char *name,
242 enum fdt_compat_id id, int *upto);
245 * Find the compatible ID for a given node.
247 * Generally each node has at least one compatible string attached to it.
248 * This function looks through our list of known compatible strings and
249 * returns the corresponding ID which matches the compatible string.
251 * @param blob FDT blob to use
252 * @param node Node containing compatible string to find
253 * @return compatible ID, or COMPAT_UNKNOWN if we cannot find a match
255 enum fdt_compat_id fdtdec_lookup(const void *blob, int node);
258 * Find the next compatible node for a peripheral.
260 * Do the first call with node = 0. This function will return a pointer to
261 * the next compatible node. Next time you call this function, pass the
262 * value returned, and the next node will be provided.
264 * @param blob FDT blob to use
265 * @param node Start node for search
266 * @param id Compatible ID to look for (enum fdt_compat_id)
267 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
269 int fdtdec_next_compatible(const void *blob, int node,
270 enum fdt_compat_id id);
273 * Find the next compatible subnode for a peripheral.
275 * Do the first call with node set to the parent and depth = 0. This
276 * function will return the offset of the next compatible node. Next time
277 * you call this function, pass the node value returned last time, with
278 * depth unchanged, and the next node will be provided.
280 * @param blob FDT blob to use
281 * @param node Start node for search
282 * @param id Compatible ID to look for (enum fdt_compat_id)
283 * @param depthp Current depth (set to 0 before first call)
284 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
286 int fdtdec_next_compatible_subnode(const void *blob, int node,
287 enum fdt_compat_id id, int *depthp);
290 * Look up an address property in a node and return the parsed address, and
291 * optionally the parsed size.
293 * This variant assumes a known and fixed number of cells are used to
294 * represent the address and size.
296 * You probably don't want to use this function directly except to parse
297 * non-standard properties, and never to parse the "reg" property. Instead,
298 * use one of the "auto" variants below, which automatically honor the
299 * #address-cells and #size-cells properties in the parent node.
301 * @param blob FDT blob
302 * @param node node to examine
303 * @param prop_name name of property to find
304 * @param index which address to retrieve from a list of addresses. Often 0.
305 * @param na the number of cells used to represent an address
306 * @param ns the number of cells used to represent a size
307 * @param sizep a pointer to store the size into. Use NULL if not required
308 * @param translate Indicates whether to translate the returned value
309 * using the parent node's ranges property.
310 * @return address, if found, or FDT_ADDR_T_NONE if not
312 fdt_addr_t fdtdec_get_addr_size_fixed(const void *blob, int node,
313 const char *prop_name, int index, int na, int ns,
314 fdt_size_t *sizep, bool translate);
317 * Look up an address property in a node and return the parsed address, and
318 * optionally the parsed size.
320 * This variant automatically determines the number of cells used to represent
321 * the address and size by parsing the provided parent node's #address-cells
322 * and #size-cells properties.
324 * @param blob FDT blob
325 * @param parent parent node of @node
326 * @param node node to examine
327 * @param prop_name name of property to find
328 * @param index which address to retrieve from a list of addresses. Often 0.
329 * @param sizep a pointer to store the size into. Use NULL if not required
330 * @param translate Indicates whether to translate the returned value
331 * using the parent node's ranges property.
332 * @return address, if found, or FDT_ADDR_T_NONE if not
334 fdt_addr_t fdtdec_get_addr_size_auto_parent(const void *blob, int parent,
335 int node, const char *prop_name, int index, fdt_size_t *sizep,
339 * Look up an address property in a node and return the parsed address, and
340 * optionally the parsed size.
342 * This variant automatically determines the number of cells used to represent
343 * the address and size by parsing the parent node's #address-cells
344 * and #size-cells properties. The parent node is automatically found.
346 * The automatic parent lookup implemented by this function is slow.
347 * Consequently, fdtdec_get_addr_size_auto_parent() should be used where
350 * @param blob FDT blob
351 * @param parent parent node of @node
352 * @param node node to examine
353 * @param prop_name name of property to find
354 * @param index which address to retrieve from a list of addresses. Often 0.
355 * @param sizep a pointer to store the size into. Use NULL if not required
356 * @param translate Indicates whether to translate the returned value
357 * using the parent node's ranges property.
358 * @return address, if found, or FDT_ADDR_T_NONE if not
360 fdt_addr_t fdtdec_get_addr_size_auto_noparent(const void *blob, int node,
361 const char *prop_name, int index, fdt_size_t *sizep,
365 * Look up an address property in a node and return the parsed address.
367 * This variant hard-codes the number of cells used to represent the address
368 * and size based on sizeof(fdt_addr_t) and sizeof(fdt_size_t). It also
369 * always returns the first address value in the property (index 0).
371 * Use of this function is not recommended due to the hard-coding of cell
372 * counts. There is no programmatic validation that these hard-coded values
373 * actually match the device tree content in any way at all. This assumption
374 * can be satisfied by manually ensuring CONFIG_PHYS_64BIT is appropriately
375 * set in the U-Boot build and exercising strict control over DT content to
376 * ensure use of matching #address-cells/#size-cells properties. However, this
377 * approach is error-prone; those familiar with DT will not expect the
378 * assumption to exist, and could easily invalidate it. If the assumption is
379 * invalidated, this function will not report the issue, and debugging will
380 * be required. Instead, use fdtdec_get_addr_size_auto_parent().
382 * @param blob FDT blob
383 * @param node node to examine
384 * @param prop_name name of property to find
385 * @return address, if found, or FDT_ADDR_T_NONE if not
387 fdt_addr_t fdtdec_get_addr(const void *blob, int node,
388 const char *prop_name);
391 * Look up an address property in a node and return the parsed address, and
392 * optionally the parsed size.
394 * This variant hard-codes the number of cells used to represent the address
395 * and size based on sizeof(fdt_addr_t) and sizeof(fdt_size_t). It also
396 * always returns the first address value in the property (index 0).
398 * Use of this function is not recommended due to the hard-coding of cell
399 * counts. There is no programmatic validation that these hard-coded values
400 * actually match the device tree content in any way at all. This assumption
401 * can be satisfied by manually ensuring CONFIG_PHYS_64BIT is appropriately
402 * set in the U-Boot build and exercising strict control over DT content to
403 * ensure use of matching #address-cells/#size-cells properties. However, this
404 * approach is error-prone; those familiar with DT will not expect the
405 * assumption to exist, and could easily invalidate it. If the assumption is
406 * invalidated, this function will not report the issue, and debugging will
407 * be required. Instead, use fdtdec_get_addr_size_auto_parent().
409 * @param blob FDT blob
410 * @param node node to examine
411 * @param prop_name name of property to find
412 * @param sizep a pointer to store the size into. Use NULL if not required
413 * @return address, if found, or FDT_ADDR_T_NONE if not
415 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
416 const char *prop_name, fdt_size_t *sizep);
419 * Look at an address property in a node and return the pci address which
420 * corresponds to the given type in the form of fdt_pci_addr.
421 * The property must hold one fdt_pci_addr with a lengh.
423 * @param blob FDT blob
424 * @param node node to examine
425 * @param type pci address type (FDT_PCI_SPACE_xxx)
426 * @param prop_name name of property to find
427 * @param addr returns pci address in the form of fdt_pci_addr
428 * @return 0 if ok, -ENOENT if the property did not exist, -EINVAL if the
429 * format of the property was invalid, -ENXIO if the requested
430 * address type was not found
432 int fdtdec_get_pci_addr(const void *blob, int node, enum fdt_pci_space type,
433 const char *prop_name, struct fdt_pci_addr *addr);
436 * Look at the compatible property of a device node that represents a PCI
437 * device and extract pci vendor id and device id from it.
439 * @param blob FDT blob
440 * @param node node to examine
441 * @param vendor vendor id of the pci device
442 * @param device device id of the pci device
443 * @return 0 if ok, negative on error
445 int fdtdec_get_pci_vendev(const void *blob, int node,
446 u16 *vendor, u16 *device);
449 * Look at the pci address of a device node that represents a PCI device
450 * and return base address of the pci device's registers.
452 * @param dev device to examine
453 * @param addr pci address in the form of fdt_pci_addr
454 * @param bar returns base address of the pci device's registers
455 * @return 0 if ok, negative on error
457 int fdtdec_get_pci_bar32(struct udevice *dev, struct fdt_pci_addr *addr,
461 * Look up a 32-bit integer property in a node and return it. The property
462 * must have at least 4 bytes of data. The value of the first cell is
465 * @param blob FDT blob
466 * @param node node to examine
467 * @param prop_name name of property to find
468 * @param default_val default value to return if the property is not found
469 * @return integer value, if found, or default_val if not
471 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
475 * Unsigned version of fdtdec_get_int. The property must have at least
476 * 4 bytes of data. The value of the first cell is returned.
478 * @param blob FDT blob
479 * @param node node to examine
480 * @param prop_name name of property to find
481 * @param default_val default value to return if the property is not found
482 * @return unsigned integer value, if found, or default_val if not
484 unsigned int fdtdec_get_uint(const void *blob, int node, const char *prop_name,
485 unsigned int default_val);
488 * Get a variable-sized number from a property
490 * This reads a number from one or more cells.
492 * @param ptr Pointer to property
493 * @param cells Number of cells containing the number
494 * @return the value in the cells
496 u64 fdtdec_get_number(const fdt32_t *ptr, unsigned int cells);
499 * Look up a 64-bit integer property in a node and return it. The property
500 * must have at least 8 bytes of data (2 cells). The first two cells are
501 * concatenated to form a 8 bytes value, where the first cell is top half and
502 * the second cell is bottom half.
504 * @param blob FDT blob
505 * @param node node to examine
506 * @param prop_name name of property to find
507 * @param default_val default value to return if the property is not found
508 * @return integer value, if found, or default_val if not
510 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
511 uint64_t default_val);
514 * Checks whether a node is enabled.
515 * This looks for a 'status' property. If this exists, then returns 1 if
516 * the status is 'ok' and 0 otherwise. If there is no status property,
517 * it returns 1 on the assumption that anything mentioned should be enabled
520 * @param blob FDT blob
521 * @param node node to examine
522 * @return integer value 0 (not enabled) or 1 (enabled)
524 int fdtdec_get_is_enabled(const void *blob, int node);
527 * Make sure we have a valid fdt available to control U-Boot.
529 * If not, a message is printed to the console if the console is ready.
531 * @return 0 if all ok, -1 if not
533 int fdtdec_prepare_fdt(void);
536 * Checks that we have a valid fdt available to control U-Boot.
538 * However, if not then for the moment nothing is done, since this function
539 * is called too early to panic().
543 int fdtdec_check_fdt(void);
546 * Find the nodes for a peripheral and return a list of them in the correct
547 * order. This is used to enumerate all the peripherals of a certain type.
549 * To use this, optionally set up a /aliases node with alias properties for
550 * a peripheral. For example, for usb you could have:
553 * usb0 = "/ehci@c5008000";
554 * usb1 = "/ehci@c5000000";
557 * Pass "usb" as the name to this function and will return a list of two
558 * nodes offsets: /ehci@c5008000 and ehci@c5000000.
560 * All nodes returned will match the compatible ID, as it is assumed that
561 * all peripherals use the same driver.
563 * If no alias node is found, then the node list will be returned in the
564 * order found in the fdt. If the aliases mention a node which doesn't
565 * exist, then this will be ignored. If nodes are found with no aliases,
566 * they will be added in any order.
568 * If there is a gap in the aliases, then this function return a 0 node at
569 * that position. The return value will also count these gaps.
571 * This function checks node properties and will not return nodes which are
572 * marked disabled (status = "disabled").
574 * @param blob FDT blob to use
575 * @param name Root name of alias to search for
576 * @param id Compatible ID to look for
577 * @param node_list Place to put list of found nodes
578 * @param maxcount Maximum number of nodes to find
579 * @return number of nodes found on success, FDT_ERR_... on error
581 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
582 enum fdt_compat_id id, int *node_list, int maxcount);
585 * This function is similar to fdtdec_find_aliases_for_id() except that it
586 * adds to the node_list that is passed in. Any 0 elements are considered
587 * available for allocation - others are considered already used and are
590 * You can use this by calling fdtdec_find_aliases_for_id() with an
591 * uninitialised array, then setting the elements that are returned to -1,
592 * say, then calling this function, perhaps with a different compat id.
593 * Any elements you get back that are >0 are new nodes added by the call
596 * Note that if you have some nodes with aliases and some without, you are
597 * sailing close to the wind. The call to fdtdec_find_aliases_for_id() with
598 * one compat_id may fill in positions for which you have aliases defined
599 * for another compat_id. When you later call *this* function with the second
600 * compat_id, the alias positions may already be used. A debug warning may
601 * be generated in this case, but it is safest to define aliases for all
602 * nodes when you care about the ordering.
604 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
605 enum fdt_compat_id id, int *node_list, int maxcount);
608 * Get the alias sequence number of a node
610 * This works out whether a node is pointed to by an alias, and if so, the
611 * sequence number of that alias. Aliases are of the form <base><num> where
612 * <num> is the sequence number. For example spi2 would be sequence number
615 * @param blob Device tree blob (if NULL, then error is returned)
616 * @param base Base name for alias (before the underscore)
617 * @param node Node to look up
618 * @param seqp This is set to the sequence number if one is found,
619 * but otherwise the value is left alone
620 * @return 0 if a sequence was found, -ve if not
622 int fdtdec_get_alias_seq(const void *blob, const char *base, int node,
626 * Get the highest alias number for susbystem.
628 * It parses all aliases and find out highest recorded alias for subsystem.
629 * Aliases are of the form <base><num> where <num> is the sequence number.
631 * @param blob Device tree blob (if NULL, then error is returned)
632 * @param base Base name for alias susbystem (before the number)
634 * @return 0 highest alias ID, -1 if not found
636 int fdtdec_get_alias_highest_id(const void *blob, const char *base);
639 * Get a property from the /chosen node
641 * @param blob Device tree blob (if NULL, then NULL is returned)
642 * @param name Property name to look up
643 * @return Value of property, or NULL if it does not exist
645 const char *fdtdec_get_chosen_prop(const void *blob, const char *name);
648 * Get the offset of the given /chosen node
650 * This looks up a property in /chosen containing the path to another node,
651 * then finds the offset of that node.
653 * @param blob Device tree blob (if NULL, then error is returned)
654 * @param name Property name, e.g. "stdout-path"
655 * @return Node offset referred to by that chosen node, or -ve FDT_ERR_...
657 int fdtdec_get_chosen_node(const void *blob, const char *name);
660 * Get the name for a compatible ID
662 * @param id Compatible ID to look for
663 * @return compatible string for that id
665 const char *fdtdec_get_compatible(enum fdt_compat_id id);
667 /* Look up a phandle and follow it to its node. Then return the offset
670 * @param blob FDT blob
671 * @param node node to examine
672 * @param prop_name name of property to find
673 * @return node offset if found, -ve error code on error
675 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name);
678 * Look up a property in a node and return its contents in an integer
679 * array of given length. The property must have at least enough data for
680 * the array (4*count bytes). It may have more, but this will be ignored.
682 * @param blob FDT blob
683 * @param node node to examine
684 * @param prop_name name of property to find
685 * @param array array to fill with data
686 * @param count number of array elements
687 * @return 0 if ok, or -FDT_ERR_NOTFOUND if the property is not found,
688 * or -FDT_ERR_BADLAYOUT if not enough data
690 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
691 u32 *array, int count);
694 * Look up a property in a node and return its contents in an integer
695 * array of given length. The property must exist but may have less data that
696 * expected (4*count bytes). It may have more, but this will be ignored.
698 * @param blob FDT blob
699 * @param node node to examine
700 * @param prop_name name of property to find
701 * @param array array to fill with data
702 * @param count number of array elements
703 * @return number of array elements if ok, or -FDT_ERR_NOTFOUND if the
704 * property is not found
706 int fdtdec_get_int_array_count(const void *blob, int node,
707 const char *prop_name, u32 *array, int count);
710 * Look up a property in a node and return a pointer to its contents as a
711 * unsigned int array of given length. The property must have at least enough
712 * data for the array ('count' cells). It may have more, but this will be
713 * ignored. The data is not copied.
715 * Note that you must access elements of the array with fdt32_to_cpu(),
716 * since the elements will be big endian even on a little endian machine.
718 * @param blob FDT blob
719 * @param node node to examine
720 * @param prop_name name of property to find
721 * @param count number of array elements
722 * @return pointer to array if found, or NULL if the property is not
723 * found or there is not enough data
725 const u32 *fdtdec_locate_array(const void *blob, int node,
726 const char *prop_name, int count);
729 * Look up a boolean property in a node and return it.
731 * A boolean properly is true if present in the device tree and false if not
732 * present, regardless of its value.
734 * @param blob FDT blob
735 * @param node node to examine
736 * @param prop_name name of property to find
737 * @return 1 if the properly is present; 0 if it isn't present
739 int fdtdec_get_bool(const void *blob, int node, const char *prop_name);
742 * Count child nodes of one parent node.
744 * @param blob FDT blob
745 * @param node parent node
746 * @return number of child node; 0 if there is not child node
748 int fdtdec_get_child_count(const void *blob, int node);
751 * Look in the FDT for a config item with the given name and return its value
752 * as a 32-bit integer. The property must have at least 4 bytes of data. The
753 * value of the first cell is returned.
755 * @param blob FDT blob to use
756 * @param prop_name Node property name
757 * @param default_val default value to return if the property is not found
758 * @return integer value, if found, or default_val if not
760 int fdtdec_get_config_int(const void *blob, const char *prop_name,
764 * Look in the FDT for a config item with the given name
765 * and return whether it exists.
767 * @param blob FDT blob
768 * @param prop_name property name to look up
769 * @return 1, if it exists, or 0 if not
771 int fdtdec_get_config_bool(const void *blob, const char *prop_name);
774 * Look in the FDT for a config item with the given name and return its value
777 * @param blob FDT blob
778 * @param prop_name property name to look up
779 * @returns property string, NULL on error.
781 char *fdtdec_get_config_string(const void *blob, const char *prop_name);
784 * Look up a property in a node and return its contents in a byte
785 * array of given length. The property must have at least enough data for
786 * the array (count bytes). It may have more, but this will be ignored.
788 * @param blob FDT blob
789 * @param node node to examine
790 * @param prop_name name of property to find
791 * @param array array to fill with data
792 * @param count number of array elements
793 * @return 0 if ok, or -FDT_ERR_MISSING if the property is not found,
794 * or -FDT_ERR_BADLAYOUT if not enough data
796 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
797 u8 *array, int count);
800 * Look up a property in a node and return a pointer to its contents as a
801 * byte array of given length. The property must have at least enough data
802 * for the array (count bytes). It may have more, but this will be ignored.
803 * The data is not copied.
805 * @param blob FDT blob
806 * @param node node to examine
807 * @param prop_name name of property to find
808 * @param count number of array elements
809 * @return pointer to byte array if found, or NULL if the property is not
810 * found or there is not enough data
812 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
813 const char *prop_name, int count);
816 * Obtain an indexed resource from a device property.
818 * @param fdt FDT blob
819 * @param node node to examine
820 * @param property name of the property to parse
821 * @param index index of the resource to retrieve
822 * @param res returns the resource
823 * @return 0 if ok, negative on error
825 int fdt_get_resource(const void *fdt, int node, const char *property,
826 unsigned int index, struct fdt_resource *res);
829 * Obtain a named resource from a device property.
831 * Look up the index of the name in a list of strings and return the resource
834 * @param fdt FDT blob
835 * @param node node to examine
836 * @param property name of the property to parse
837 * @param prop_names name of the property containing the list of names
838 * @param name the name of the entry to look up
839 * @param res returns the resource
841 int fdt_get_named_resource(const void *fdt, int node, const char *property,
842 const char *prop_names, const char *name,
843 struct fdt_resource *res);
845 /* Display timings from linux include/video/display_timing.h */
847 DISPLAY_FLAGS_HSYNC_LOW = 1 << 0,
848 DISPLAY_FLAGS_HSYNC_HIGH = 1 << 1,
849 DISPLAY_FLAGS_VSYNC_LOW = 1 << 2,
850 DISPLAY_FLAGS_VSYNC_HIGH = 1 << 3,
852 /* data enable flag */
853 DISPLAY_FLAGS_DE_LOW = 1 << 4,
854 DISPLAY_FLAGS_DE_HIGH = 1 << 5,
855 /* drive data on pos. edge */
856 DISPLAY_FLAGS_PIXDATA_POSEDGE = 1 << 6,
857 /* drive data on neg. edge */
858 DISPLAY_FLAGS_PIXDATA_NEGEDGE = 1 << 7,
859 DISPLAY_FLAGS_INTERLACED = 1 << 8,
860 DISPLAY_FLAGS_DOUBLESCAN = 1 << 9,
861 DISPLAY_FLAGS_DOUBLECLK = 1 << 10,
865 * A single signal can be specified via a range of minimal and maximal values
866 * with a typical value, that lies somewhere inbetween.
868 struct timing_entry {
875 * Single "mode" entry. This describes one set of signal timings a display can
876 * have in one setting. This struct can later be converted to struct videomode
877 * (see include/video/videomode.h). As each timing_entry can be defined as a
878 * range, one struct display_timing may become multiple struct videomodes.
880 * Example: hsync active high, vsync active low
883 * Video ______________________XXXXXXXXXXXXXXXXXXXXXX_____________________
884 * |<- sync ->|<- back ->|<----- active ----->|<- front ->|<- sync..
885 * | | porch | | porch |
887 * HSync _|¯¯¯¯¯¯¯¯¯¯|___________________________________________|¯¯¯¯¯¯¯¯¯
889 * VSync ¯|__________|¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯|_________
891 struct display_timing {
892 struct timing_entry pixelclock;
894 struct timing_entry hactive; /* hor. active video */
895 struct timing_entry hfront_porch; /* hor. front porch */
896 struct timing_entry hback_porch; /* hor. back porch */
897 struct timing_entry hsync_len; /* hor. sync len */
899 struct timing_entry vactive; /* ver. active video */
900 struct timing_entry vfront_porch; /* ver. front porch */
901 struct timing_entry vback_porch; /* ver. back porch */
902 struct timing_entry vsync_len; /* ver. sync len */
904 enum display_flags flags; /* display flags */
905 bool hdmi_monitor; /* is hdmi monitor? */
909 * fdtdec_decode_display_timing() - decode display timings
911 * Decode display timings from the supplied 'display-timings' node.
912 * See doc/device-tree-bindings/video/display-timing.txt for binding
915 * @param blob FDT blob
916 * @param node 'display-timing' node containing the timing subnodes
917 * @param index Index number to read (0=first timing subnode)
918 * @param config Place to put timings
919 * @return 0 if OK, -FDT_ERR_NOTFOUND if not found
921 int fdtdec_decode_display_timing(const void *blob, int node, int index,
922 struct display_timing *config);
925 * fdtdec_setup_mem_size_base_fdt() - decode and setup gd->ram_size and
928 * Decode the /memory 'reg' property to determine the size and start of the
929 * first memory bank, populate the global data with the size and start of the
930 * first bank of memory.
932 * This function should be called from a boards dram_init(). This helper
933 * function allows for boards to query the device tree for DRAM size and start
934 * address instead of hard coding the value in the case where the memory size
935 * and start address cannot be detected automatically.
937 * @param blob FDT blob
939 * @return 0 if OK, -EINVAL if the /memory node or reg property is missing or
942 int fdtdec_setup_mem_size_base_fdt(const void *blob);
945 * fdtdec_setup_mem_size_base() - decode and setup gd->ram_size and
948 * Decode the /memory 'reg' property to determine the size and start of the
949 * first memory bank, populate the global data with the size and start of the
950 * first bank of memory.
952 * This function should be called from a boards dram_init(). This helper
953 * function allows for boards to query the device tree for DRAM size and start
954 * address instead of hard coding the value in the case where the memory size
955 * and start address cannot be detected automatically.
957 * @return 0 if OK, -EINVAL if the /memory node or reg property is missing or
960 int fdtdec_setup_mem_size_base(void);
963 * fdtdec_setup_memory_banksize_fdt() - decode and populate gd->bd->bi_dram
965 * Decode the /memory 'reg' property to determine the address and size of the
966 * memory banks. Use this data to populate the global data board info with the
967 * phys address and size of memory banks.
969 * This function should be called from a boards dram_init_banksize(). This
970 * helper function allows for boards to query the device tree for memory bank
971 * information instead of hard coding the information in cases where it cannot
972 * be detected automatically.
974 * @param blob FDT blob
976 * @return 0 if OK, -EINVAL if the /memory node or reg property is missing or
979 int fdtdec_setup_memory_banksize_fdt(const void *blob);
982 * fdtdec_setup_memory_banksize() - decode and populate gd->bd->bi_dram
984 * Decode the /memory 'reg' property to determine the address and size of the
985 * memory banks. Use this data to populate the global data board info with the
986 * phys address and size of memory banks.
988 * This function should be called from a boards dram_init_banksize(). This
989 * helper function allows for boards to query the device tree for memory bank
990 * information instead of hard coding the information in cases where it cannot
991 * be detected automatically.
993 * @return 0 if OK, -EINVAL if the /memory node or reg property is missing or
996 int fdtdec_setup_memory_banksize(void);
999 * Set up the device tree ready for use
1001 int fdtdec_setup(void);
1003 #if CONFIG_IS_ENABLED(MULTI_DTB_FIT)
1005 * fdtdec_resetup() - Set up the device tree again
1007 * The main difference with fdtdec_setup() is that it returns if the fdt has
1008 * changed because a better match has been found.
1009 * This is typically used for boards that rely on a DM driver to detect the
1010 * board type. This function sould be called by the board code after the stuff
1011 * needed by board_fit_config_name_match() to operate porperly is available.
1012 * If this functions signals that a rescan is necessary, the board code must
1013 * unbind all the drivers using dm_uninit() and then rescan the DT with
1014 * dm_init_and_scan().
1016 * @param rescan Returns a flag indicating that fdt has changed and rescanning
1017 * the fdt is required
1019 * @return 0 if OK, -ve on error
1021 int fdtdec_resetup(int *rescan);
1025 * Board-specific FDT initialization. Returns the address to a device tree blob.
1026 * Called when CONFIG_OF_BOARD is defined, or if CONFIG_OF_SEPARATE is defined
1027 * and the board implements it.
1029 void *board_fdt_blob_setup(void);
1032 * Decode the size of memory
1034 * RAM size is normally set in a /memory node and consists of a list of
1035 * (base, size) cells in the 'reg' property. This information is used to
1036 * determine the total available memory as well as the address and size
1039 * Optionally the memory configuration can vary depending on a board id,
1040 * typically read from strapping resistors or an EEPROM on the board.
1042 * Finally, memory size can be detected (within certain limits) by probing
1043 * the available memory. It is safe to do so within the limits provides by
1044 * the board's device tree information. This makes it possible to produce
1045 * boards with different memory sizes, where the device tree specifies the
1046 * maximum memory configuration, and the smaller memory configuration is
1049 * This function decodes that information, returning the memory base address,
1050 * size and bank information. See the memory.txt binding for full
1053 * @param blob Device tree blob
1054 * @param area Name of node to check (NULL means "/memory")
1055 * @param board_id Board ID to look up
1056 * @param basep Returns base address of first memory bank (NULL to
1058 * @param sizep Returns total memory size (NULL to ignore)
1059 * @param bd Updated with the memory bank information (NULL to skip)
1060 * @return 0 if OK, -ve on error
1062 int fdtdec_decode_ram_size(const void *blob, const char *area, int board_id,
1063 phys_addr_t *basep, phys_size_t *sizep,
1064 struct bd_info *bd);