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 typedef fdt64_t fdt_val_t;
32 #define FDT_ADDR_T_NONE (-1U)
33 #define fdt_addr_to_cpu(reg) be32_to_cpu(reg)
34 #define fdt_size_to_cpu(reg) be32_to_cpu(reg)
35 typedef fdt32_t fdt_val_t;
38 /* Information obtained about memory from the FDT */
46 #ifdef CONFIG_SPL_BUILD
52 #if CONFIG_IS_ENABLED(OF_PRIOR_STAGE)
53 extern phys_addr_t prior_stage_fdt_address;
57 * Information about a resource. start is the first address of the resource
58 * and end is the last address (inclusive). The length of the resource will
59 * be equal to: end - start + 1.
67 FDT_PCI_SPACE_CONFIG = 0,
68 FDT_PCI_SPACE_IO = 0x01000000,
69 FDT_PCI_SPACE_MEM32 = 0x02000000,
70 FDT_PCI_SPACE_MEM64 = 0x03000000,
71 FDT_PCI_SPACE_MEM32_PREF = 0x42000000,
72 FDT_PCI_SPACE_MEM64_PREF = 0x43000000,
75 #define FDT_PCI_ADDR_CELLS 3
76 #define FDT_PCI_SIZE_CELLS 2
77 #define FDT_PCI_REG_SIZE \
78 ((FDT_PCI_ADDR_CELLS + FDT_PCI_SIZE_CELLS) * sizeof(u32))
81 * The Open Firmware spec defines PCI physical address as follows:
83 * bits# 31 .... 24 23 .... 16 15 .... 08 07 .... 00
85 * phys.hi cell: npt000ss bbbbbbbb dddddfff rrrrrrrr
86 * phys.mid cell: hhhhhhhh hhhhhhhh hhhhhhhh hhhhhhhh
87 * phys.lo cell: llllllll llllllll llllllll llllllll
91 * n: is 0 if the address is relocatable, 1 otherwise
92 * p: is 1 if addressable region is prefetchable, 0 otherwise
93 * t: is 1 if the address is aliased (for non-relocatable I/O) below 1MB
94 * (for Memory), or below 64KB (for relocatable I/O)
95 * ss: is the space code, denoting the address space
96 * bbbbbbbb: is the 8-bit Bus Number
97 * ddddd: is the 5-bit Device Number
98 * fff: is the 3-bit Function Number
99 * rrrrrrrr: is the 8-bit Register Number
100 * hhhhhhhh: is a 32-bit unsigned number
101 * llllllll: is a 32-bit unsigned number
103 struct fdt_pci_addr {
110 * Compute the size of a resource.
112 * @param res the resource to operate on
113 * @return the size of the resource
115 static inline fdt_size_t fdt_resource_size(const struct fdt_resource *res)
117 return res->end - res->start + 1;
121 * Compat types that we know about and for which we might have drivers.
122 * Each is named COMPAT_<dir>_<filename> where <dir> is the directory
127 COMPAT_NVIDIA_TEGRA20_EMC, /* Tegra20 memory controller */
128 COMPAT_NVIDIA_TEGRA20_EMC_TABLE, /* Tegra20 memory timing table */
129 COMPAT_NVIDIA_TEGRA20_NAND, /* Tegra2 NAND controller */
130 COMPAT_NVIDIA_TEGRA124_XUSB_PADCTL,
131 /* Tegra124 XUSB pad controller */
132 COMPAT_NVIDIA_TEGRA210_XUSB_PADCTL,
133 /* Tegra210 XUSB pad controller */
134 COMPAT_SMSC_LAN9215, /* SMSC 10/100 Ethernet LAN9215 */
135 COMPAT_SAMSUNG_EXYNOS5_SROMC, /* Exynos5 SROMC */
136 COMPAT_SAMSUNG_S3C2440_I2C, /* Exynos I2C Controller */
137 COMPAT_SAMSUNG_EXYNOS5_SOUND, /* Exynos Sound */
138 COMPAT_WOLFSON_WM8994_CODEC, /* Wolfson WM8994 Sound Codec */
139 COMPAT_SAMSUNG_EXYNOS_USB_PHY, /* Exynos phy controller for usb2.0 */
140 COMPAT_SAMSUNG_EXYNOS5_USB3_PHY,/* Exynos phy controller for usb3.0 */
141 COMPAT_SAMSUNG_EXYNOS_TMU, /* Exynos TMU */
142 COMPAT_SAMSUNG_EXYNOS_MIPI_DSI, /* Exynos mipi dsi */
143 COMPAT_SAMSUNG_EXYNOS_DWMMC, /* Exynos DWMMC controller */
144 COMPAT_SAMSUNG_EXYNOS_MMC, /* Exynos MMC controller */
145 COMPAT_GENERIC_SPI_FLASH, /* Generic SPI Flash chip */
146 COMPAT_MAXIM_98095_CODEC, /* MAX98095 Codec */
147 COMPAT_SAMSUNG_EXYNOS5_I2C, /* Exynos5 High Speed I2C Controller */
148 COMPAT_SAMSUNG_EXYNOS_SYSMMU, /* Exynos sysmmu */
149 COMPAT_INTEL_MICROCODE, /* Intel microcode update */
150 COMPAT_AMS_AS3722, /* AMS AS3722 PMIC */
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 an address property in a node and return the pci address which
423 * corresponds to the given type in the form of fdt_pci_addr.
424 * The property must hold one fdt_pci_addr with a lengh.
426 * @param blob FDT blob
427 * @param node node to examine
428 * @param type pci address type (FDT_PCI_SPACE_xxx)
429 * @param prop_name name of property to find
430 * @param addr returns pci address in the form of fdt_pci_addr
431 * @return 0 if ok, -ENOENT if the property did not exist, -EINVAL if the
432 * format of the property was invalid, -ENXIO if the requested
433 * address type was not found
435 int fdtdec_get_pci_addr(const void *blob, int node, enum fdt_pci_space type,
436 const char *prop_name, struct fdt_pci_addr *addr);
439 * Look at the compatible property of a device node that represents a PCI
440 * device and extract pci vendor id and device id from it.
442 * @param blob FDT blob
443 * @param node node to examine
444 * @param vendor vendor id of the pci device
445 * @param device device id of the pci device
446 * @return 0 if ok, negative on error
448 int fdtdec_get_pci_vendev(const void *blob, int node,
449 u16 *vendor, u16 *device);
452 * Look at the pci address of a device node that represents a PCI device
453 * and return base address of the pci device's registers.
455 * @param dev device to examine
456 * @param addr pci address in the form of fdt_pci_addr
457 * @param bar returns base address of the pci device's registers
458 * @return 0 if ok, negative on error
460 int fdtdec_get_pci_bar32(struct udevice *dev, struct fdt_pci_addr *addr,
464 * Look up a 32-bit integer property in a node and return it. The property
465 * must have at least 4 bytes of data. The value of the first cell is
468 * @param blob FDT blob
469 * @param node node to examine
470 * @param prop_name name of property to find
471 * @param default_val default value to return if the property is not found
472 * @return integer value, if found, or default_val if not
474 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
478 * Unsigned version of fdtdec_get_int. The property must have at least
479 * 4 bytes of data. The value of the first cell is returned.
481 * @param blob FDT blob
482 * @param node node to examine
483 * @param prop_name name of property to find
484 * @param default_val default value to return if the property is not found
485 * @return unsigned integer value, if found, or default_val if not
487 unsigned int fdtdec_get_uint(const void *blob, int node, const char *prop_name,
488 unsigned int default_val);
491 * Get a variable-sized number from a property
493 * This reads a number from one or more cells.
495 * @param ptr Pointer to property
496 * @param cells Number of cells containing the number
497 * @return the value in the cells
499 u64 fdtdec_get_number(const fdt32_t *ptr, unsigned int cells);
502 * Look up a 64-bit integer property in a node and return it. The property
503 * must have at least 8 bytes of data (2 cells). The first two cells are
504 * concatenated to form a 8 bytes value, where the first cell is top half and
505 * the second cell is bottom half.
507 * @param blob FDT blob
508 * @param node node to examine
509 * @param prop_name name of property to find
510 * @param default_val default value to return if the property is not found
511 * @return integer value, if found, or default_val if not
513 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
514 uint64_t default_val);
517 * Checks whether a node is enabled.
518 * This looks for a 'status' property. If this exists, then returns 1 if
519 * the status is 'ok' and 0 otherwise. If there is no status property,
520 * it returns 1 on the assumption that anything mentioned should be enabled
523 * @param blob FDT blob
524 * @param node node to examine
525 * @return integer value 0 (not enabled) or 1 (enabled)
527 int fdtdec_get_is_enabled(const void *blob, int node);
530 * Make sure we have a valid fdt available to control U-Boot.
532 * If not, a message is printed to the console if the console is ready.
534 * @return 0 if all ok, -1 if not
536 int fdtdec_prepare_fdt(void);
539 * Checks that we have a valid fdt available to control U-Boot.
541 * However, if not then for the moment nothing is done, since this function
542 * is called too early to panic().
546 int fdtdec_check_fdt(void);
549 * Find the nodes for a peripheral and return a list of them in the correct
550 * order. This is used to enumerate all the peripherals of a certain type.
552 * To use this, optionally set up a /aliases node with alias properties for
553 * a peripheral. For example, for usb you could have:
556 * usb0 = "/ehci@c5008000";
557 * usb1 = "/ehci@c5000000";
560 * Pass "usb" as the name to this function and will return a list of two
561 * nodes offsets: /ehci@c5008000 and ehci@c5000000.
563 * All nodes returned will match the compatible ID, as it is assumed that
564 * all peripherals use the same driver.
566 * If no alias node is found, then the node list will be returned in the
567 * order found in the fdt. If the aliases mention a node which doesn't
568 * exist, then this will be ignored. If nodes are found with no aliases,
569 * they will be added in any order.
571 * If there is a gap in the aliases, then this function return a 0 node at
572 * that position. The return value will also count these gaps.
574 * This function checks node properties and will not return nodes which are
575 * marked disabled (status = "disabled").
577 * @param blob FDT blob to use
578 * @param name Root name of alias to search for
579 * @param id Compatible ID to look for
580 * @param node_list Place to put list of found nodes
581 * @param maxcount Maximum number of nodes to find
582 * @return number of nodes found on success, FDT_ERR_... on error
584 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
585 enum fdt_compat_id id, int *node_list, int maxcount);
588 * This function is similar to fdtdec_find_aliases_for_id() except that it
589 * adds to the node_list that is passed in. Any 0 elements are considered
590 * available for allocation - others are considered already used and are
593 * You can use this by calling fdtdec_find_aliases_for_id() with an
594 * uninitialised array, then setting the elements that are returned to -1,
595 * say, then calling this function, perhaps with a different compat id.
596 * Any elements you get back that are >0 are new nodes added by the call
599 * Note that if you have some nodes with aliases and some without, you are
600 * sailing close to the wind. The call to fdtdec_find_aliases_for_id() with
601 * one compat_id may fill in positions for which you have aliases defined
602 * for another compat_id. When you later call *this* function with the second
603 * compat_id, the alias positions may already be used. A debug warning may
604 * be generated in this case, but it is safest to define aliases for all
605 * nodes when you care about the ordering.
607 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
608 enum fdt_compat_id id, int *node_list, int maxcount);
611 * Get the alias sequence number of a node
613 * This works out whether a node is pointed to by an alias, and if so, the
614 * sequence number of that alias. Aliases are of the form <base><num> where
615 * <num> is the sequence number. For example spi2 would be sequence number
618 * @param blob Device tree blob (if NULL, then error is returned)
619 * @param base Base name for alias (before the underscore)
620 * @param node Node to look up
621 * @param seqp This is set to the sequence number if one is found,
622 * but otherwise the value is left alone
623 * @return 0 if a sequence was found, -ve if not
625 int fdtdec_get_alias_seq(const void *blob, const char *base, int node,
629 * Get a property from the /chosen node
631 * @param blob Device tree blob (if NULL, then NULL is returned)
632 * @param name Property name to look up
633 * @return Value of property, or NULL if it does not exist
635 const char *fdtdec_get_chosen_prop(const void *blob, const char *name);
638 * Get the offset of the given /chosen node
640 * This looks up a property in /chosen containing the path to another node,
641 * then finds the offset of that node.
643 * @param blob Device tree blob (if NULL, then error is returned)
644 * @param name Property name, e.g. "stdout-path"
645 * @return Node offset referred to by that chosen node, or -ve FDT_ERR_...
647 int fdtdec_get_chosen_node(const void *blob, const char *name);
650 * Get the name for a compatible ID
652 * @param id Compatible ID to look for
653 * @return compatible string for that id
655 const char *fdtdec_get_compatible(enum fdt_compat_id id);
657 /* Look up a phandle and follow it to its node. Then return the offset
660 * @param blob FDT blob
661 * @param node node to examine
662 * @param prop_name name of property to find
663 * @return node offset if found, -ve error code on error
665 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name);
668 * Look up a property in a node and return its contents in an integer
669 * array of given length. The property must have at least enough data for
670 * the array (4*count bytes). It may have more, but this will be ignored.
672 * @param blob FDT blob
673 * @param node node to examine
674 * @param prop_name name of property to find
675 * @param array array to fill with data
676 * @param count number of array elements
677 * @return 0 if ok, or -FDT_ERR_NOTFOUND if the property is not found,
678 * or -FDT_ERR_BADLAYOUT if not enough data
680 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
681 u32 *array, int count);
684 * Look up a property in a node and return its contents in an integer
685 * array of given length. The property must exist but may have less data that
686 * expected (4*count bytes). It may have more, but this will be ignored.
688 * @param blob FDT blob
689 * @param node node to examine
690 * @param prop_name name of property to find
691 * @param array array to fill with data
692 * @param count number of array elements
693 * @return number of array elements if ok, or -FDT_ERR_NOTFOUND if the
694 * property is not found
696 int fdtdec_get_int_array_count(const void *blob, int node,
697 const char *prop_name, u32 *array, int count);
700 * Look up a property in a node and return a pointer to its contents as a
701 * unsigned int array of given length. The property must have at least enough
702 * data for the array ('count' cells). It may have more, but this will be
703 * ignored. The data is not copied.
705 * Note that you must access elements of the array with fdt32_to_cpu(),
706 * since the elements will be big endian even on a little endian machine.
708 * @param blob FDT blob
709 * @param node node to examine
710 * @param prop_name name of property to find
711 * @param count number of array elements
712 * @return pointer to array if found, or NULL if the property is not
713 * found or there is not enough data
715 const u32 *fdtdec_locate_array(const void *blob, int node,
716 const char *prop_name, int count);
719 * Look up a boolean property in a node and return it.
721 * A boolean properly is true if present in the device tree and false if not
722 * present, regardless of its value.
724 * @param blob FDT blob
725 * @param node node to examine
726 * @param prop_name name of property to find
727 * @return 1 if the properly is present; 0 if it isn't present
729 int fdtdec_get_bool(const void *blob, int node, const char *prop_name);
732 * Count child nodes of one parent node.
734 * @param blob FDT blob
735 * @param node parent node
736 * @return number of child node; 0 if there is not child node
738 int fdtdec_get_child_count(const void *blob, int node);
741 * Look in the FDT for a config item with the given name and return its value
742 * as a 32-bit integer. The property must have at least 4 bytes of data. The
743 * value of the first cell is returned.
745 * @param blob FDT blob to use
746 * @param prop_name Node property name
747 * @param default_val default value to return if the property is not found
748 * @return integer value, if found, or default_val if not
750 int fdtdec_get_config_int(const void *blob, const char *prop_name,
754 * Look in the FDT for a config item with the given name
755 * and return whether it exists.
757 * @param blob FDT blob
758 * @param prop_name property name to look up
759 * @return 1, if it exists, or 0 if not
761 int fdtdec_get_config_bool(const void *blob, const char *prop_name);
764 * Look in the FDT for a config item with the given name and return its value
767 * @param blob FDT blob
768 * @param prop_name property name to look up
769 * @returns property string, NULL on error.
771 char *fdtdec_get_config_string(const void *blob, const char *prop_name);
774 * Look up a property in a node and return its contents in a byte
775 * array of given length. The property must have at least enough data for
776 * the array (count bytes). It may have more, but this will be ignored.
778 * @param blob FDT blob
779 * @param node node to examine
780 * @param prop_name name of property to find
781 * @param array array to fill with data
782 * @param count number of array elements
783 * @return 0 if ok, or -FDT_ERR_MISSING if the property is not found,
784 * or -FDT_ERR_BADLAYOUT if not enough data
786 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
787 u8 *array, int count);
790 * Look up a property in a node and return a pointer to its contents as a
791 * byte array of given length. The property must have at least enough data
792 * for the array (count bytes). It may have more, but this will be ignored.
793 * The data is not copied.
795 * @param blob FDT blob
796 * @param node node to examine
797 * @param prop_name name of property to find
798 * @param count number of array elements
799 * @return pointer to byte array if found, or NULL if the property is not
800 * found or there is not enough data
802 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
803 const char *prop_name, int count);
806 * Obtain an indexed resource from a device property.
808 * @param fdt FDT blob
809 * @param node node to examine
810 * @param property name of the property to parse
811 * @param index index of the resource to retrieve
812 * @param res returns the resource
813 * @return 0 if ok, negative on error
815 int fdt_get_resource(const void *fdt, int node, const char *property,
816 unsigned int index, struct fdt_resource *res);
819 * Obtain a named resource from a device property.
821 * Look up the index of the name in a list of strings and return the resource
824 * @param fdt FDT blob
825 * @param node node to examine
826 * @param property name of the property to parse
827 * @param prop_names name of the property containing the list of names
828 * @param name the name of the entry to look up
829 * @param res returns the resource
831 int fdt_get_named_resource(const void *fdt, int node, const char *property,
832 const char *prop_names, const char *name,
833 struct fdt_resource *res);
835 /* Display timings from linux include/video/display_timing.h */
837 DISPLAY_FLAGS_HSYNC_LOW = 1 << 0,
838 DISPLAY_FLAGS_HSYNC_HIGH = 1 << 1,
839 DISPLAY_FLAGS_VSYNC_LOW = 1 << 2,
840 DISPLAY_FLAGS_VSYNC_HIGH = 1 << 3,
842 /* data enable flag */
843 DISPLAY_FLAGS_DE_LOW = 1 << 4,
844 DISPLAY_FLAGS_DE_HIGH = 1 << 5,
845 /* drive data on pos. edge */
846 DISPLAY_FLAGS_PIXDATA_POSEDGE = 1 << 6,
847 /* drive data on neg. edge */
848 DISPLAY_FLAGS_PIXDATA_NEGEDGE = 1 << 7,
849 DISPLAY_FLAGS_INTERLACED = 1 << 8,
850 DISPLAY_FLAGS_DOUBLESCAN = 1 << 9,
851 DISPLAY_FLAGS_DOUBLECLK = 1 << 10,
855 * A single signal can be specified via a range of minimal and maximal values
856 * with a typical value, that lies somewhere inbetween.
858 struct timing_entry {
865 * Single "mode" entry. This describes one set of signal timings a display can
866 * have in one setting. This struct can later be converted to struct videomode
867 * (see include/video/videomode.h). As each timing_entry can be defined as a
868 * range, one struct display_timing may become multiple struct videomodes.
870 * Example: hsync active high, vsync active low
873 * Video ______________________XXXXXXXXXXXXXXXXXXXXXX_____________________
874 * |<- sync ->|<- back ->|<----- active ----->|<- front ->|<- sync..
875 * | | porch | | porch |
877 * HSync _|¯¯¯¯¯¯¯¯¯¯|___________________________________________|¯¯¯¯¯¯¯¯¯
879 * VSync ¯|__________|¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯|_________
881 struct display_timing {
882 struct timing_entry pixelclock;
884 struct timing_entry hactive; /* hor. active video */
885 struct timing_entry hfront_porch; /* hor. front porch */
886 struct timing_entry hback_porch; /* hor. back porch */
887 struct timing_entry hsync_len; /* hor. sync len */
889 struct timing_entry vactive; /* ver. active video */
890 struct timing_entry vfront_porch; /* ver. front porch */
891 struct timing_entry vback_porch; /* ver. back porch */
892 struct timing_entry vsync_len; /* ver. sync len */
894 enum display_flags flags; /* display flags */
895 bool hdmi_monitor; /* is hdmi monitor? */
899 * fdtdec_decode_display_timing() - decode display timings
901 * Decode display timings from the supplied 'display-timings' node.
902 * See doc/device-tree-bindings/video/display-timing.txt for binding
905 * @param blob FDT blob
906 * @param node 'display-timing' node containing the timing subnodes
907 * @param index Index number to read (0=first timing subnode)
908 * @param config Place to put timings
909 * @return 0 if OK, -FDT_ERR_NOTFOUND if not found
911 int fdtdec_decode_display_timing(const void *blob, int node, int index,
912 struct display_timing *config);
915 * fdtdec_setup_mem_size_base() - decode and setup gd->ram_size and
918 * Decode the /memory 'reg' property to determine the size and start of the
919 * first memory bank, populate the global data with the size and start of the
920 * first bank of memory.
922 * This function should be called from a boards dram_init(). This helper
923 * function allows for boards to query the device tree for DRAM size and start
924 * address instead of hard coding the value in the case where the memory size
925 * and start address cannot be detected automatically.
927 * @return 0 if OK, -EINVAL if the /memory node or reg property is missing or
930 int fdtdec_setup_mem_size_base(void);
933 * fdtdec_setup_memory_banksize() - decode and populate gd->bd->bi_dram
935 * Decode the /memory 'reg' property to determine the address and size of the
936 * memory banks. Use this data to populate the global data board info with the
937 * phys address and size of memory banks.
939 * This function should be called from a boards dram_init_banksize(). This
940 * helper function allows for boards to query the device tree for memory bank
941 * information instead of hard coding the information in cases where it cannot
942 * be detected automatically.
944 * @return 0 if OK, -EINVAL if the /memory node or reg property is missing or
947 int fdtdec_setup_memory_banksize(void);
950 * Set up the device tree ready for use
952 int fdtdec_setup(void);
954 #if CONFIG_IS_ENABLED(MULTI_DTB_FIT)
956 * fdtdec_resetup() - Set up the device tree again
958 * The main difference with fdtdec_setup() is that it returns if the fdt has
959 * changed because a better match has been found.
960 * This is typically used for boards that rely on a DM driver to detect the
961 * board type. This function sould be called by the board code after the stuff
962 * needed by board_fit_config_name_match() to operate porperly is available.
963 * If this functions signals that a rescan is necessary, the board code must
964 * unbind all the drivers using dm_uninit() and then rescan the DT with
965 * dm_init_and_scan().
967 * @param rescan Returns a flag indicating that fdt has changed and rescanning
968 * the fdt is required
970 * @return 0 if OK, -ve on error
972 int fdtdec_resetup(int *rescan);
976 * Board-specific FDT initialization. Returns the address to a device tree blob.
977 * Called when CONFIG_OF_BOARD is defined, or if CONFIG_OF_SEPARATE is defined
978 * and the board implements it.
980 void *board_fdt_blob_setup(void);
983 * Decode the size of memory
985 * RAM size is normally set in a /memory node and consists of a list of
986 * (base, size) cells in the 'reg' property. This information is used to
987 * determine the total available memory as well as the address and size
990 * Optionally the memory configuration can vary depending on a board id,
991 * typically read from strapping resistors or an EEPROM on the board.
993 * Finally, memory size can be detected (within certain limits) by probing
994 * the available memory. It is safe to do so within the limits provides by
995 * the board's device tree information. This makes it possible to produce
996 * boards with different memory sizes, where the device tree specifies the
997 * maximum memory configuration, and the smaller memory configuration is
1000 * This function decodes that information, returning the memory base address,
1001 * size and bank information. See the memory.txt binding for full
1004 * @param blob Device tree blob
1005 * @param area Name of node to check (NULL means "/memory")
1006 * @param board_id Board ID to look up
1007 * @param basep Returns base address of first memory bank (NULL to
1009 * @param sizep Returns total memory size (NULL to ignore)
1010 * @param bd Updated with the memory bank information (NULL to skip)
1011 * @return 0 if OK, -ve on error
1013 int fdtdec_decode_ram_size(const void *blob, const char *area, int board_id,
1014 phys_addr_t *basep, phys_size_t *sizep,
1015 struct bd_info *bd);