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_KBC, /* Tegra20 Keyboard */
122 COMPAT_NVIDIA_TEGRA20_NAND, /* Tegra2 NAND controller */
123 COMPAT_NVIDIA_TEGRA20_PWM, /* Tegra 2 PWM controller */
124 COMPAT_NVIDIA_TEGRA124_DC, /* Tegra 124 Display controller */
125 COMPAT_NVIDIA_TEGRA124_SOR, /* Tegra 124 Serial Output Resource */
126 COMPAT_NVIDIA_TEGRA124_PMC, /* Tegra 124 power mgmt controller */
127 COMPAT_NVIDIA_TEGRA20_DC, /* Tegra 2 Display controller */
128 COMPAT_NVIDIA_TEGRA210_SDMMC, /* Tegra210 SDMMC controller */
129 COMPAT_NVIDIA_TEGRA124_SDMMC, /* Tegra124 SDMMC controller */
130 COMPAT_NVIDIA_TEGRA30_SDMMC, /* Tegra30 SDMMC controller */
131 COMPAT_NVIDIA_TEGRA20_SDMMC, /* Tegra20 SDMMC controller */
132 COMPAT_NVIDIA_TEGRA124_PCIE, /* Tegra 124 PCIe controller */
133 COMPAT_NVIDIA_TEGRA210_PCIE, /* Tegra 210 PCIe controller */
134 COMPAT_NVIDIA_TEGRA30_PCIE, /* Tegra 30 PCIe controller */
135 COMPAT_NVIDIA_TEGRA20_PCIE, /* Tegra 20 PCIe controller */
136 COMPAT_NVIDIA_TEGRA124_XUSB_PADCTL,
137 /* Tegra124 XUSB pad controller */
138 COMPAT_NVIDIA_TEGRA210_XUSB_PADCTL,
139 /* Tegra210 XUSB pad controller */
140 COMPAT_SMSC_LAN9215, /* SMSC 10/100 Ethernet LAN9215 */
141 COMPAT_SAMSUNG_EXYNOS5_SROMC, /* Exynos5 SROMC */
142 COMPAT_SAMSUNG_S3C2440_I2C, /* Exynos I2C Controller */
143 COMPAT_SAMSUNG_EXYNOS5_SOUND, /* Exynos Sound */
144 COMPAT_WOLFSON_WM8994_CODEC, /* Wolfson WM8994 Sound Codec */
145 COMPAT_GOOGLE_CROS_EC_KEYB, /* Google CROS_EC Keyboard */
146 COMPAT_SAMSUNG_EXYNOS_USB_PHY, /* Exynos phy controller for usb2.0 */
147 COMPAT_SAMSUNG_EXYNOS5_USB3_PHY,/* Exynos phy controller for usb3.0 */
148 COMPAT_SAMSUNG_EXYNOS_TMU, /* Exynos TMU */
149 COMPAT_SAMSUNG_EXYNOS_FIMD, /* Exynos Display controller */
150 COMPAT_SAMSUNG_EXYNOS_MIPI_DSI, /* Exynos mipi dsi */
151 COMPAT_SAMSUNG_EXYNOS5_DP, /* Exynos Display port controller */
152 COMPAT_SAMSUNG_EXYNOS_DWMMC, /* Exynos DWMMC controller */
153 COMPAT_SAMSUNG_EXYNOS_MMC, /* Exynos MMC controller */
154 COMPAT_SAMSUNG_EXYNOS_SERIAL, /* Exynos UART */
155 COMPAT_MAXIM_MAX77686_PMIC, /* MAX77686 PMIC */
156 COMPAT_GENERIC_SPI_FLASH, /* Generic SPI Flash chip */
157 COMPAT_MAXIM_98095_CODEC, /* MAX98095 Codec */
158 COMPAT_SAMSUNG_EXYNOS5_I2C, /* Exynos5 High Speed I2C Controller */
159 COMPAT_SANDBOX_LCD_SDL, /* Sandbox LCD emulation with SDL */
160 COMPAT_SAMSUNG_EXYNOS_SYSMMU, /* Exynos sysmmu */
161 COMPAT_INTEL_MICROCODE, /* Intel microcode update */
162 COMPAT_MEMORY_SPD, /* Memory SPD information */
163 COMPAT_INTEL_PANTHERPOINT_AHCI, /* Intel Pantherpoint AHCI */
164 COMPAT_INTEL_MODEL_206AX, /* Intel Model 206AX CPU */
165 COMPAT_INTEL_GMA, /* Intel Graphics Media Accelerator */
166 COMPAT_AMS_AS3722, /* AMS AS3722 PMIC */
167 COMPAT_INTEL_ICH_SPI, /* Intel ICH7/9 SPI controller */
168 COMPAT_INTEL_QRK_MRC, /* Intel Quark MRC */
169 COMPAT_INTEL_X86_PINCTRL, /* Intel ICH7/9 pin control */
170 COMPAT_SOCIONEXT_XHCI, /* Socionext UniPhier xHCI */
171 COMPAT_INTEL_PCH, /* Intel PCH */
172 COMPAT_INTEL_IRQ_ROUTER, /* Intel Interrupt Router */
173 COMPAT_ALTERA_SOCFPGA_DWMAC, /* SoCFPGA Ethernet controller */
174 COMPAT_ALTERA_SOCFPGA_DWMMC, /* SoCFPGA DWMMC controller */
175 COMPAT_INTEL_BAYTRAIL_FSP, /* Intel Bay Trail FSP */
176 COMPAT_INTEL_BAYTRAIL_FSP_MDP, /* Intel FSP memory-down params */
181 #define MAX_PHANDLE_ARGS 16
182 struct fdtdec_phandle_args {
185 uint32_t args[MAX_PHANDLE_ARGS];
189 * fdtdec_parse_phandle_with_args() - Find a node pointed by phandle in a list
191 * This function is useful to parse lists of phandles and their arguments.
204 * list = <&phandle1 1 2 &phandle2 3>;
207 * To get a device_node of the `node2' node you may call this:
208 * fdtdec_parse_phandle_with_args(blob, node3, "list", "#list-cells", 0, 1,
211 * (This function is a modified version of __of_parse_phandle_with_args() from
214 * @blob: Pointer to device tree
215 * @src_node: Offset of device tree node containing a list
216 * @list_name: property name that contains a list
217 * @cells_name: property name that specifies the phandles' arguments count,
218 * or NULL to use @cells_count
219 * @cells_count: Cell count to use if @cells_name is NULL
220 * @index: index of a phandle to parse out
221 * @out_args: optional pointer to output arguments structure (will be filled)
222 * @return 0 on success (with @out_args filled out if not NULL), -ENOENT if
223 * @list_name does not exist, a phandle was not found, @cells_name
224 * could not be found, the arguments were truncated or there were too
228 int fdtdec_parse_phandle_with_args(const void *blob, int src_node,
229 const char *list_name,
230 const char *cells_name,
231 int cell_count, int index,
232 struct fdtdec_phandle_args *out_args);
235 * Find the next numbered alias for a peripheral. This is used to enumerate
236 * all the peripherals of a certain type.
238 * Do the first call with *upto = 0. Assuming /aliases/<name>0 exists then
239 * this function will return a pointer to the node the alias points to, and
240 * then update *upto to 1. Next time you call this function, the next node
243 * All nodes returned will match the compatible ID, as it is assumed that
244 * all peripherals use the same driver.
246 * @param blob FDT blob to use
247 * @param name Root name of alias to search for
248 * @param id Compatible ID to look for
249 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
251 int fdtdec_next_alias(const void *blob, const char *name,
252 enum fdt_compat_id id, int *upto);
255 * Find the compatible ID for a given node.
257 * Generally each node has at least one compatible string attached to it.
258 * This function looks through our list of known compatible strings and
259 * returns the corresponding ID which matches the compatible string.
261 * @param blob FDT blob to use
262 * @param node Node containing compatible string to find
263 * @return compatible ID, or COMPAT_UNKNOWN if we cannot find a match
265 enum fdt_compat_id fdtdec_lookup(const void *blob, int node);
268 * Find the next compatible node for a peripheral.
270 * Do the first call with node = 0. This function will return a pointer to
271 * the next compatible node. Next time you call this function, pass the
272 * value returned, and the next node will be provided.
274 * @param blob FDT blob to use
275 * @param node Start node for search
276 * @param id Compatible ID to look for (enum fdt_compat_id)
277 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
279 int fdtdec_next_compatible(const void *blob, int node,
280 enum fdt_compat_id id);
283 * Find the next compatible subnode for a peripheral.
285 * Do the first call with node set to the parent and depth = 0. This
286 * function will return the offset of the next compatible node. Next time
287 * you call this function, pass the node value returned last time, with
288 * depth unchanged, and the next node will be provided.
290 * @param blob FDT blob to use
291 * @param node Start node for search
292 * @param id Compatible ID to look for (enum fdt_compat_id)
293 * @param depthp Current depth (set to 0 before first call)
294 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
296 int fdtdec_next_compatible_subnode(const void *blob, int node,
297 enum fdt_compat_id id, int *depthp);
300 * Look up an address property in a node and return the parsed address, and
301 * optionally the parsed size.
303 * This variant assumes a known and fixed number of cells are used to
304 * represent the address and size.
306 * You probably don't want to use this function directly except to parse
307 * non-standard properties, and never to parse the "reg" property. Instead,
308 * use one of the "auto" variants below, which automatically honor the
309 * #address-cells and #size-cells properties in the parent node.
311 * @param blob FDT blob
312 * @param node node to examine
313 * @param prop_name name of property to find
314 * @param index which address to retrieve from a list of addresses. Often 0.
315 * @param na the number of cells used to represent an address
316 * @param ns the number of cells used to represent a size
317 * @param sizep a pointer to store the size into. Use NULL if not required
318 * @return address, if found, or FDT_ADDR_T_NONE if not
320 fdt_addr_t fdtdec_get_addr_size_fixed(const void *blob, int node,
321 const char *prop_name, int index, int na, int ns,
325 * Look up an address property in a node and return the parsed address, and
326 * optionally the parsed size.
328 * This variant automatically determines the number of cells used to represent
329 * the address and size by parsing the provided parent node's #address-cells
330 * and #size-cells properties.
332 * @param blob FDT blob
333 * @param parent parent node of @node
334 * @param node node to examine
335 * @param prop_name name of property to find
336 * @param index which address to retrieve from a list of addresses. Often 0.
337 * @param sizep a pointer to store the size into. Use NULL if not required
338 * @return address, if found, or FDT_ADDR_T_NONE if not
340 fdt_addr_t fdtdec_get_addr_size_auto_parent(const void *blob, int parent,
341 int node, const char *prop_name, int index, fdt_size_t *sizep);
344 * Look up an address property in a node and return the parsed address, and
345 * optionally the parsed size.
347 * This variant automatically determines the number of cells used to represent
348 * the address and size by parsing the parent node's #address-cells
349 * and #size-cells properties. The parent node is automatically found.
351 * The automatic parent lookup implemented by this function is slow.
352 * Consequently, fdtdec_get_addr_size_auto_parent() should be used where
355 * @param blob FDT blob
356 * @param parent parent node of @node
357 * @param node node to examine
358 * @param prop_name name of property to find
359 * @param index which address to retrieve from a list of addresses. Often 0.
360 * @param sizep a pointer to store the size into. Use NULL if not required
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);
367 * Look up an address property in a node and return the parsed address.
369 * This variant hard-codes the number of cells used to represent the address
370 * and size based on sizeof(fdt_addr_t) and sizeof(fdt_size_t). It also
371 * always returns the first address value in the property (index 0).
373 * Use of this function is not recommended due to the hard-coding of cell
374 * counts. There is no programmatic validation that these hard-coded values
375 * actually match the device tree content in any way at all. This assumption
376 * can be satisfied by manually ensuring CONFIG_PHYS_64BIT is appropriately
377 * set in the U-Boot build and exercising strict control over DT content to
378 * ensure use of matching #address-cells/#size-cells properties. However, this
379 * approach is error-prone; those familiar with DT will not expect the
380 * assumption to exist, and could easily invalidate it. If the assumption is
381 * invalidated, this function will not report the issue, and debugging will
382 * be required. Instead, use fdtdec_get_addr_size_auto_parent().
384 * @param blob FDT blob
385 * @param node node to examine
386 * @param prop_name name of property to find
387 * @return address, if found, or FDT_ADDR_T_NONE if not
389 fdt_addr_t fdtdec_get_addr(const void *blob, int node,
390 const char *prop_name);
393 * Look up an address property in a node and return the parsed address, and
394 * optionally the parsed size.
396 * This variant hard-codes the number of cells used to represent the address
397 * and size based on sizeof(fdt_addr_t) and sizeof(fdt_size_t). It also
398 * always returns the first address value in the property (index 0).
400 * Use of this function is not recommended due to the hard-coding of cell
401 * counts. There is no programmatic validation that these hard-coded values
402 * actually match the device tree content in any way at all. This assumption
403 * can be satisfied by manually ensuring CONFIG_PHYS_64BIT is appropriately
404 * set in the U-Boot build and exercising strict control over DT content to
405 * ensure use of matching #address-cells/#size-cells properties. However, this
406 * approach is error-prone; those familiar with DT will not expect the
407 * assumption to exist, and could easily invalidate it. If the assumption is
408 * invalidated, this function will not report the issue, and debugging will
409 * be required. Instead, use fdtdec_get_addr_size_auto_parent().
411 * @param blob FDT blob
412 * @param node node to examine
413 * @param prop_name name of property to find
414 * @param sizep a pointer to store the size into. Use NULL if not required
415 * @return address, if found, or FDT_ADDR_T_NONE if not
417 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
418 const char *prop_name, fdt_size_t *sizep);
421 * Look at an address property in a node and return the pci address which
422 * corresponds to the given type in the form of fdt_pci_addr.
423 * The property must hold one fdt_pci_addr with a lengh.
425 * @param blob FDT blob
426 * @param node node to examine
427 * @param type pci address type (FDT_PCI_SPACE_xxx)
428 * @param prop_name name of property to find
429 * @param addr returns pci address in the form of fdt_pci_addr
430 * @return 0 if ok, -ENOENT if the property did not exist, -EINVAL if the
431 * format of the property was invalid, -ENXIO if the requested
432 * address type was not found
434 int fdtdec_get_pci_addr(const void *blob, int node, enum fdt_pci_space type,
435 const char *prop_name, struct fdt_pci_addr *addr);
438 * Look at the compatible property of a device node that represents a PCI
439 * device and extract pci vendor id and device id from it.
441 * @param blob FDT blob
442 * @param node node to examine
443 * @param vendor vendor id of the pci device
444 * @param device device id of the pci device
445 * @return 0 if ok, negative on error
447 int fdtdec_get_pci_vendev(const void *blob, int node,
448 u16 *vendor, u16 *device);
451 * Look at the pci address of a device node that represents a PCI device
452 * and parse the bus, device and function number from it. For some cases
453 * like the bus number encoded in reg property is not correct after pci
454 * enumeration, this function looks through the node's compatible strings
455 * to get these numbers extracted instead.
457 * @param blob FDT blob
458 * @param node node to examine
459 * @param addr pci address in the form of fdt_pci_addr
460 * @param bdf returns bus, device, function triplet
461 * @return 0 if ok, negative on error
463 int fdtdec_get_pci_bdf(const void *blob, int node,
464 struct fdt_pci_addr *addr, pci_dev_t *bdf);
467 * Look at the pci address of a device node that represents a PCI device
468 * and return base address of the pci device's registers.
470 * @param blob FDT blob
471 * @param node node to examine
472 * @param addr pci address in the form of fdt_pci_addr
473 * @param bar returns base address of the pci device's registers
474 * @return 0 if ok, negative on error
476 int fdtdec_get_pci_bar32(const void *blob, int node,
477 struct fdt_pci_addr *addr, u32 *bar);
480 * Look up a 32-bit integer property in a node and return it. The property
481 * must have at least 4 bytes of data. The value of the first cell is
484 * @param blob FDT blob
485 * @param node node to examine
486 * @param prop_name name of property to find
487 * @param default_val default value to return if the property is not found
488 * @return integer value, if found, or default_val if not
490 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
494 * Unsigned version of fdtdec_get_int. The property must have at least
495 * 4 bytes of data. The value of the first cell is returned.
497 * @param blob FDT blob
498 * @param node node to examine
499 * @param prop_name name of property to find
500 * @param default_val default value to return if the property is not found
501 * @return unsigned integer value, if found, or default_val if not
503 unsigned int fdtdec_get_uint(const void *blob, int node, const char *prop_name,
504 unsigned int default_val);
507 * Get a variable-sized number from a property
509 * This reads a number from one or more cells.
511 * @param ptr Pointer to property
512 * @param cells Number of cells containing the number
513 * @return the value in the cells
515 u64 fdtdec_get_number(const fdt32_t *ptr, unsigned int cells);
518 * Look up a 64-bit integer property in a node and return it. The property
519 * must have at least 8 bytes of data (2 cells). The first two cells are
520 * concatenated to form a 8 bytes value, where the first cell is top half and
521 * the second cell is bottom half.
523 * @param blob FDT blob
524 * @param node node to examine
525 * @param prop_name name of property to find
526 * @param default_val default value to return if the property is not found
527 * @return integer value, if found, or default_val if not
529 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
530 uint64_t default_val);
533 * Checks whether a node is enabled.
534 * This looks for a 'status' property. If this exists, then returns 1 if
535 * the status is 'ok' and 0 otherwise. If there is no status property,
536 * it returns 1 on the assumption that anything mentioned should be enabled
539 * @param blob FDT blob
540 * @param node node to examine
541 * @return integer value 0 (not enabled) or 1 (enabled)
543 int fdtdec_get_is_enabled(const void *blob, int node);
546 * Make sure we have a valid fdt available to control U-Boot.
548 * If not, a message is printed to the console if the console is ready.
550 * @return 0 if all ok, -1 if not
552 int fdtdec_prepare_fdt(void);
555 * Checks that we have a valid fdt available to control U-Boot.
557 * However, if not then for the moment nothing is done, since this function
558 * is called too early to panic().
562 int fdtdec_check_fdt(void);
565 * Find the nodes for a peripheral and return a list of them in the correct
566 * order. This is used to enumerate all the peripherals of a certain type.
568 * To use this, optionally set up a /aliases node with alias properties for
569 * a peripheral. For example, for usb you could have:
572 * usb0 = "/ehci@c5008000";
573 * usb1 = "/ehci@c5000000";
576 * Pass "usb" as the name to this function and will return a list of two
577 * nodes offsets: /ehci@c5008000 and ehci@c5000000.
579 * All nodes returned will match the compatible ID, as it is assumed that
580 * all peripherals use the same driver.
582 * If no alias node is found, then the node list will be returned in the
583 * order found in the fdt. If the aliases mention a node which doesn't
584 * exist, then this will be ignored. If nodes are found with no aliases,
585 * they will be added in any order.
587 * If there is a gap in the aliases, then this function return a 0 node at
588 * that position. The return value will also count these gaps.
590 * This function checks node properties and will not return nodes which are
591 * marked disabled (status = "disabled").
593 * @param blob FDT blob to use
594 * @param name Root name of alias to search for
595 * @param id Compatible ID to look for
596 * @param node_list Place to put list of found nodes
597 * @param maxcount Maximum number of nodes to find
598 * @return number of nodes found on success, FTD_ERR_... on error
600 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
601 enum fdt_compat_id id, int *node_list, int maxcount);
604 * This function is similar to fdtdec_find_aliases_for_id() except that it
605 * adds to the node_list that is passed in. Any 0 elements are considered
606 * available for allocation - others are considered already used and are
609 * You can use this by calling fdtdec_find_aliases_for_id() with an
610 * uninitialised array, then setting the elements that are returned to -1,
611 * say, then calling this function, perhaps with a different compat id.
612 * Any elements you get back that are >0 are new nodes added by the call
615 * Note that if you have some nodes with aliases and some without, you are
616 * sailing close to the wind. The call to fdtdec_find_aliases_for_id() with
617 * one compat_id may fill in positions for which you have aliases defined
618 * for another compat_id. When you later call *this* function with the second
619 * compat_id, the alias positions may already be used. A debug warning may
620 * be generated in this case, but it is safest to define aliases for all
621 * nodes when you care about the ordering.
623 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
624 enum fdt_compat_id id, int *node_list, int maxcount);
627 * Get the alias sequence number of a node
629 * This works out whether a node is pointed to by an alias, and if so, the
630 * sequence number of that alias. Aliases are of the form <base><num> where
631 * <num> is the sequence number. For example spi2 would be sequence number
634 * @param blob Device tree blob (if NULL, then error is returned)
635 * @param base Base name for alias (before the underscore)
636 * @param node Node to look up
637 * @param seqp This is set to the sequence number if one is found,
638 * but otherwise the value is left alone
639 * @return 0 if a sequence was found, -ve if not
641 int fdtdec_get_alias_seq(const void *blob, const char *base, int node,
645 * Get a property from the /chosen node
647 * @param blob Device tree blob (if NULL, then NULL is returned)
648 * @param name Property name to look up
649 * @return Value of property, or NULL if it does not exist
651 const char *fdtdec_get_chosen_prop(const void *blob, const char *name);
654 * Get the offset of the given /chosen node
656 * This looks up a property in /chosen containing the path to another node,
657 * then finds the offset of that node.
659 * @param blob Device tree blob (if NULL, then error is returned)
660 * @param name Property name, e.g. "stdout-path"
661 * @return Node offset referred to by that chosen node, or -ve FDT_ERR_...
663 int fdtdec_get_chosen_node(const void *blob, const char *name);
666 * Get the name for a compatible ID
668 * @param id Compatible ID to look for
669 * @return compatible string for that id
671 const char *fdtdec_get_compatible(enum fdt_compat_id id);
673 /* Look up a phandle and follow it to its node. Then return the offset
676 * @param blob FDT blob
677 * @param node node to examine
678 * @param prop_name name of property to find
679 * @return node offset if found, -ve error code on error
681 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name);
684 * Look up a property in a node and return its contents in an integer
685 * array of given length. The property must have at least enough data for
686 * the array (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 0 if ok, or -FDT_ERR_NOTFOUND if the property is not found,
694 * or -FDT_ERR_BADLAYOUT if not enough data
696 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
697 u32 *array, int count);
700 * Look up a property in a node and return its contents in an integer
701 * array of given length. The property must exist but may have less data that
702 * expected (4*count bytes). It may have more, but this will be ignored.
704 * @param blob FDT blob
705 * @param node node to examine
706 * @param prop_name name of property to find
707 * @param array array to fill with data
708 * @param count number of array elements
709 * @return number of array elements if ok, or -FDT_ERR_NOTFOUND if the
710 * property is not found
712 int fdtdec_get_int_array_count(const void *blob, int node,
713 const char *prop_name, u32 *array, int count);
716 * Look up a property in a node and return a pointer to its contents as a
717 * unsigned int array of given length. The property must have at least enough
718 * data for the array ('count' cells). It may have more, but this will be
719 * ignored. The data is not copied.
721 * Note that you must access elements of the array with fdt32_to_cpu(),
722 * since the elements will be big endian even on a little endian machine.
724 * @param blob FDT blob
725 * @param node node to examine
726 * @param prop_name name of property to find
727 * @param count number of array elements
728 * @return pointer to array if found, or NULL if the property is not
729 * found or there is not enough data
731 const u32 *fdtdec_locate_array(const void *blob, int node,
732 const char *prop_name, int count);
735 * Look up a boolean property in a node and return it.
737 * A boolean properly is true if present in the device tree and false if not
738 * present, regardless of its value.
740 * @param blob FDT blob
741 * @param node node to examine
742 * @param prop_name name of property to find
743 * @return 1 if the properly is present; 0 if it isn't present
745 int fdtdec_get_bool(const void *blob, int node, const char *prop_name);
748 * Look in the FDT for a config item with the given name and return its value
749 * as a 32-bit integer. The property must have at least 4 bytes of data. The
750 * value of the first cell is returned.
752 * @param blob FDT blob to use
753 * @param prop_name Node property name
754 * @param default_val default value to return if the property is not found
755 * @return integer value, if found, or default_val if not
757 int fdtdec_get_config_int(const void *blob, const char *prop_name,
761 * Look in the FDT for a config item with the given name
762 * and return whether it exists.
764 * @param blob FDT blob
765 * @param prop_name property name to look up
766 * @return 1, if it exists, or 0 if not
768 int fdtdec_get_config_bool(const void *blob, const char *prop_name);
771 * Look in the FDT for a config item with the given name and return its value
774 * @param blob FDT blob
775 * @param prop_name property name to look up
776 * @returns property string, NULL on error.
778 char *fdtdec_get_config_string(const void *blob, const char *prop_name);
781 * Look up a property in a node and return its contents in a byte
782 * array of given length. The property must have at least enough data for
783 * the array (count bytes). It may have more, but this will be ignored.
785 * @param blob FDT blob
786 * @param node node to examine
787 * @param prop_name name of property to find
788 * @param array array to fill with data
789 * @param count number of array elements
790 * @return 0 if ok, or -FDT_ERR_MISSING if the property is not found,
791 * or -FDT_ERR_BADLAYOUT if not enough data
793 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
794 u8 *array, int count);
797 * Look up a property in a node and return a pointer to its contents as a
798 * byte array of given length. The property must have at least enough data
799 * for the array (count bytes). It may have more, but this will be ignored.
800 * The data is not copied.
802 * @param blob FDT blob
803 * @param node node to examine
804 * @param prop_name name of property to find
805 * @param count number of array elements
806 * @return pointer to byte array if found, or NULL if the property is not
807 * found or there is not enough data
809 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
810 const char *prop_name, int count);
813 * Look up a property in a node which contains a memory region address and
814 * size. Then return a pointer to this address.
816 * The property must hold one address with a length. This is only tested on
819 * @param blob FDT blob
820 * @param node node to examine
821 * @param prop_name name of property to find
822 * @param basep Returns base address of region
823 * @param size Returns size of region
824 * @return 0 if ok, -1 on error (property not found)
826 int fdtdec_decode_region(const void *blob, int node, const char *prop_name,
827 fdt_addr_t *basep, fdt_size_t *sizep);
829 enum fmap_compress_t {
840 /* A flash map entry, containing an offset and length */
844 uint32_t used; /* Number of bytes used in region */
845 enum fmap_compress_t compress_algo; /* Compression type */
846 enum fmap_hash_t hash_algo; /* Hash algorithm */
847 const uint8_t *hash; /* Hash value */
848 int hash_size; /* Hash size */
852 * Read a flash entry from the fdt
854 * @param blob FDT blob
855 * @param node Offset of node to read
856 * @param name Name of node being read
857 * @param entry Place to put offset and size of this node
858 * @return 0 if ok, -ve on error
860 int fdtdec_read_fmap_entry(const void *blob, int node, const char *name,
861 struct fmap_entry *entry);
864 * Obtain an indexed resource from a device property.
866 * @param fdt FDT blob
867 * @param node node to examine
868 * @param property name of the property to parse
869 * @param index index of the resource to retrieve
870 * @param res returns the resource
871 * @return 0 if ok, negative on error
873 int fdt_get_resource(const void *fdt, int node, const char *property,
874 unsigned int index, struct fdt_resource *res);
877 * Obtain a named resource from a device property.
879 * Look up the index of the name in a list of strings and return the resource
882 * @param fdt FDT blob
883 * @param node node to examine
884 * @param property name of the property to parse
885 * @param prop_names name of the property containing the list of names
886 * @param name the name of the entry to look up
887 * @param res returns the resource
889 int fdt_get_named_resource(const void *fdt, int node, const char *property,
890 const char *prop_names, const char *name,
891 struct fdt_resource *res);
894 * Decode a named region within a memory bank of a given type.
896 * This function handles selection of a memory region. The region is
897 * specified as an offset/size within a particular type of memory.
899 * The properties used are:
901 * <mem_type>-memory<suffix> for the name of the memory bank
902 * <mem_type>-offset<suffix> for the offset in that bank
904 * The property value must have an offset and a size. The function checks
905 * that the region is entirely within the memory bank.5
907 * @param blob FDT blob
908 * @param node Node containing the properties (-1 for /config)
909 * @param mem_type Type of memory to use, which is a name, such as
910 * "u-boot" or "kernel".
911 * @param suffix String to append to the memory/offset
913 * @param basep Returns base of region
914 * @param sizep Returns size of region
915 * @return 0 if OK, -ive on error
917 int fdtdec_decode_memory_region(const void *blob, int node,
918 const char *mem_type, const char *suffix,
919 fdt_addr_t *basep, fdt_size_t *sizep);
921 /* Display timings from linux include/video/display_timing.h */
923 DISPLAY_FLAGS_HSYNC_LOW = 1 << 0,
924 DISPLAY_FLAGS_HSYNC_HIGH = 1 << 1,
925 DISPLAY_FLAGS_VSYNC_LOW = 1 << 2,
926 DISPLAY_FLAGS_VSYNC_HIGH = 1 << 3,
928 /* data enable flag */
929 DISPLAY_FLAGS_DE_LOW = 1 << 4,
930 DISPLAY_FLAGS_DE_HIGH = 1 << 5,
931 /* drive data on pos. edge */
932 DISPLAY_FLAGS_PIXDATA_POSEDGE = 1 << 6,
933 /* drive data on neg. edge */
934 DISPLAY_FLAGS_PIXDATA_NEGEDGE = 1 << 7,
935 DISPLAY_FLAGS_INTERLACED = 1 << 8,
936 DISPLAY_FLAGS_DOUBLESCAN = 1 << 9,
937 DISPLAY_FLAGS_DOUBLECLK = 1 << 10,
941 * A single signal can be specified via a range of minimal and maximal values
942 * with a typical value, that lies somewhere inbetween.
944 struct timing_entry {
951 * Single "mode" entry. This describes one set of signal timings a display can
952 * have in one setting. This struct can later be converted to struct videomode
953 * (see include/video/videomode.h). As each timing_entry can be defined as a
954 * range, one struct display_timing may become multiple struct videomodes.
956 * Example: hsync active high, vsync active low
959 * Video ______________________XXXXXXXXXXXXXXXXXXXXXX_____________________
960 * |<- sync ->|<- back ->|<----- active ----->|<- front ->|<- sync..
961 * | | porch | | porch |
963 * HSync _|¯¯¯¯¯¯¯¯¯¯|___________________________________________|¯¯¯¯¯¯¯¯¯
965 * VSync ¯|__________|¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯|_________
967 struct display_timing {
968 struct timing_entry pixelclock;
970 struct timing_entry hactive; /* hor. active video */
971 struct timing_entry hfront_porch; /* hor. front porch */
972 struct timing_entry hback_porch; /* hor. back porch */
973 struct timing_entry hsync_len; /* hor. sync len */
975 struct timing_entry vactive; /* ver. active video */
976 struct timing_entry vfront_porch; /* ver. front porch */
977 struct timing_entry vback_porch; /* ver. back porch */
978 struct timing_entry vsync_len; /* ver. sync len */
980 enum display_flags flags; /* display flags */
984 * fdtdec_decode_display_timing() - decode display timings
986 * Decode display timings from the supplied 'display-timings' node.
987 * See doc/device-tree-bindings/video/display-timing.txt for binding
990 * @param blob FDT blob
991 * @param node 'display-timing' node containing the timing subnodes
992 * @param index Index number to read (0=first timing subnode)
993 * @param config Place to put timings
994 * @return 0 if OK, -FDT_ERR_NOTFOUND if not found
996 int fdtdec_decode_display_timing(const void *blob, int node, int index,
997 struct display_timing *config);
999 * Set up the device tree ready for use
1001 int fdtdec_setup(void);