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 #ifdef CONFIG_PHYS_64BIT
25 typedef u64 fdt_addr_t;
26 typedef u64 fdt_size_t;
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 typedef u32 fdt_addr_t;
32 typedef u32 fdt_size_t;
33 #define FDT_ADDR_T_NONE (-1U)
34 #define fdt_addr_to_cpu(reg) be32_to_cpu(reg)
35 #define fdt_size_to_cpu(reg) be32_to_cpu(reg)
38 /* Information obtained about memory from the FDT */
44 #ifdef CONFIG_SPL_BUILD
50 #ifdef CONFIG_OF_CONTROL
51 # if defined(CONFIG_SPL_BUILD) && defined(SPL_DISABLE_OF_CONTROL)
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_KBC, /* Tegra20 Keyboard */
134 COMPAT_NVIDIA_TEGRA20_NAND, /* Tegra2 NAND controller */
135 COMPAT_NVIDIA_TEGRA20_PWM, /* Tegra 2 PWM controller */
136 COMPAT_NVIDIA_TEGRA124_DC, /* Tegra 124 Display controller */
137 COMPAT_NVIDIA_TEGRA124_SOR, /* Tegra 124 Serial Output Resource */
138 COMPAT_NVIDIA_TEGRA124_PMC, /* Tegra 124 power mgmt controller */
139 COMPAT_NVIDIA_TEGRA20_DC, /* Tegra 2 Display controller */
140 COMPAT_NVIDIA_TEGRA210_SDMMC, /* Tegra210 SDMMC controller */
141 COMPAT_NVIDIA_TEGRA124_SDMMC, /* Tegra124 SDMMC controller */
142 COMPAT_NVIDIA_TEGRA30_SDMMC, /* Tegra30 SDMMC controller */
143 COMPAT_NVIDIA_TEGRA20_SDMMC, /* Tegra20 SDMMC controller */
144 COMPAT_NVIDIA_TEGRA124_PCIE, /* Tegra 124 PCIe controller */
145 COMPAT_NVIDIA_TEGRA30_PCIE, /* Tegra 30 PCIe controller */
146 COMPAT_NVIDIA_TEGRA20_PCIE, /* Tegra 20 PCIe controller */
147 COMPAT_NVIDIA_TEGRA124_XUSB_PADCTL,
148 /* Tegra124 XUSB pad controller */
149 COMPAT_NVIDIA_TEGRA210_XUSB_PADCTL,
150 /* Tegra210 XUSB pad controller */
151 COMPAT_SMSC_LAN9215, /* SMSC 10/100 Ethernet LAN9215 */
152 COMPAT_SAMSUNG_EXYNOS5_SROMC, /* Exynos5 SROMC */
153 COMPAT_SAMSUNG_S3C2440_I2C, /* Exynos I2C Controller */
154 COMPAT_SAMSUNG_EXYNOS5_SOUND, /* Exynos Sound */
155 COMPAT_WOLFSON_WM8994_CODEC, /* Wolfson WM8994 Sound Codec */
156 COMPAT_GOOGLE_CROS_EC_KEYB, /* Google CROS_EC Keyboard */
157 COMPAT_SAMSUNG_EXYNOS_USB_PHY, /* Exynos phy controller for usb2.0 */
158 COMPAT_SAMSUNG_EXYNOS5_USB3_PHY,/* Exynos phy controller for usb3.0 */
159 COMPAT_SAMSUNG_EXYNOS_TMU, /* Exynos TMU */
160 COMPAT_SAMSUNG_EXYNOS_FIMD, /* Exynos Display controller */
161 COMPAT_SAMSUNG_EXYNOS_MIPI_DSI, /* Exynos mipi dsi */
162 COMPAT_SAMSUNG_EXYNOS5_DP, /* Exynos Display port controller */
163 COMPAT_SAMSUNG_EXYNOS_DWMMC, /* Exynos DWMMC controller */
164 COMPAT_SAMSUNG_EXYNOS_MMC, /* Exynos MMC controller */
165 COMPAT_SAMSUNG_EXYNOS_SERIAL, /* Exynos UART */
166 COMPAT_MAXIM_MAX77686_PMIC, /* MAX77686 PMIC */
167 COMPAT_GENERIC_SPI_FLASH, /* Generic SPI Flash chip */
168 COMPAT_MAXIM_98095_CODEC, /* MAX98095 Codec */
169 COMPAT_INFINEON_SLB9635_TPM, /* Infineon SLB9635 TPM */
170 COMPAT_INFINEON_SLB9645_TPM, /* Infineon SLB9645 TPM */
171 COMPAT_SAMSUNG_EXYNOS5_I2C, /* Exynos5 High Speed I2C Controller */
172 COMPAT_SANDBOX_LCD_SDL, /* Sandbox LCD emulation with SDL */
173 COMPAT_NXP_PTN3460, /* NXP PTN3460 DP/LVDS bridge */
174 COMPAT_SAMSUNG_EXYNOS_SYSMMU, /* Exynos sysmmu */
175 COMPAT_PARADE_PS8625, /* Parade PS8622 EDP->LVDS bridge */
176 COMPAT_INTEL_MICROCODE, /* Intel microcode update */
177 COMPAT_MEMORY_SPD, /* Memory SPD information */
178 COMPAT_INTEL_PANTHERPOINT_AHCI, /* Intel Pantherpoint AHCI */
179 COMPAT_INTEL_MODEL_206AX, /* Intel Model 206AX CPU */
180 COMPAT_INTEL_GMA, /* Intel Graphics Media Accelerator */
181 COMPAT_AMS_AS3722, /* AMS AS3722 PMIC */
182 COMPAT_INTEL_ICH_SPI, /* Intel ICH7/9 SPI controller */
183 COMPAT_INTEL_QRK_MRC, /* Intel Quark MRC */
184 COMPAT_INTEL_X86_PINCTRL, /* Intel ICH7/9 pin control */
185 COMPAT_SOCIONEXT_XHCI, /* Socionext UniPhier xHCI */
186 COMPAT_INTEL_PCH, /* Intel PCH */
187 COMPAT_INTEL_IRQ_ROUTER, /* Intel Interrupt Router */
192 #define MAX_PHANDLE_ARGS 16
193 struct fdtdec_phandle_args {
196 uint32_t args[MAX_PHANDLE_ARGS];
200 * fdtdec_parse_phandle_with_args() - Find a node pointed by phandle in a list
202 * This function is useful to parse lists of phandles and their arguments.
215 * list = <&phandle1 1 2 &phandle2 3>;
218 * To get a device_node of the `node2' node you may call this:
219 * fdtdec_parse_phandle_with_args(blob, node3, "list", "#list-cells", 0, 1,
222 * (This function is a modified version of __of_parse_phandle_with_args() from
225 * @blob: Pointer to device tree
226 * @src_node: Offset of device tree node containing a list
227 * @list_name: property name that contains a list
228 * @cells_name: property name that specifies the phandles' arguments count,
229 * or NULL to use @cells_count
230 * @cells_count: Cell count to use if @cells_name is NULL
231 * @index: index of a phandle to parse out
232 * @out_args: optional pointer to output arguments structure (will be filled)
233 * @return 0 on success (with @out_args filled out if not NULL), -ENOENT if
234 * @list_name does not exist, a phandle was not found, @cells_name
235 * could not be found, the arguments were truncated or there were too
239 int fdtdec_parse_phandle_with_args(const void *blob, int src_node,
240 const char *list_name,
241 const char *cells_name,
242 int cell_count, int index,
243 struct fdtdec_phandle_args *out_args);
246 * Find the next numbered alias for a peripheral. This is used to enumerate
247 * all the peripherals of a certain type.
249 * Do the first call with *upto = 0. Assuming /aliases/<name>0 exists then
250 * this function will return a pointer to the node the alias points to, and
251 * then update *upto to 1. Next time you call this function, the next node
254 * All nodes returned will match the compatible ID, as it is assumed that
255 * all peripherals use the same driver.
257 * @param blob FDT blob to use
258 * @param name Root name of alias to search for
259 * @param id Compatible ID to look for
260 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
262 int fdtdec_next_alias(const void *blob, const char *name,
263 enum fdt_compat_id id, int *upto);
266 * Find the compatible ID for a given node.
268 * Generally each node has at least one compatible string attached to it.
269 * This function looks through our list of known compatible strings and
270 * returns the corresponding ID which matches the compatible string.
272 * @param blob FDT blob to use
273 * @param node Node containing compatible string to find
274 * @return compatible ID, or COMPAT_UNKNOWN if we cannot find a match
276 enum fdt_compat_id fdtdec_lookup(const void *blob, int node);
279 * Find the next compatible node for a peripheral.
281 * Do the first call with node = 0. This function will return a pointer to
282 * the next compatible node. Next time you call this function, pass the
283 * value returned, and the next node will be provided.
285 * @param blob FDT blob to use
286 * @param node Start node for search
287 * @param id Compatible ID to look for (enum fdt_compat_id)
288 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
290 int fdtdec_next_compatible(const void *blob, int node,
291 enum fdt_compat_id id);
294 * Find the next compatible subnode for a peripheral.
296 * Do the first call with node set to the parent and depth = 0. This
297 * function will return the offset of the next compatible node. Next time
298 * you call this function, pass the node value returned last time, with
299 * depth unchanged, and the next node will be provided.
301 * @param blob FDT blob to use
302 * @param node Start node for search
303 * @param id Compatible ID to look for (enum fdt_compat_id)
304 * @param depthp Current depth (set to 0 before first call)
305 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
307 int fdtdec_next_compatible_subnode(const void *blob, int node,
308 enum fdt_compat_id id, int *depthp);
311 * Look up an address property in a node and return it as an address.
312 * The property must hold either one address with no trailing data or
313 * one address with a length. This is only tested on 32-bit machines.
315 * @param blob FDT blob
316 * @param node node to examine
317 * @param prop_name name of property to find
318 * @return address, if found, or FDT_ADDR_T_NONE if not
320 fdt_addr_t fdtdec_get_addr(const void *blob, int node,
321 const char *prop_name);
324 * Look up an address property in a node and return it as an address.
325 * The property must hold one address with a length. This is only tested
326 * on 32-bit machines.
328 * @param blob FDT blob
329 * @param node node to examine
330 * @param prop_name name of property to find
331 * @return address, if found, or FDT_ADDR_T_NONE if not
333 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
334 const char *prop_name, fdt_size_t *sizep);
337 * Look at an address property in a node and return the pci address which
338 * corresponds to the given type in the form of fdt_pci_addr.
339 * The property must hold one fdt_pci_addr with a lengh.
341 * @param blob FDT blob
342 * @param node node to examine
343 * @param type pci address type (FDT_PCI_SPACE_xxx)
344 * @param prop_name name of property to find
345 * @param addr returns pci address in the form of fdt_pci_addr
346 * @return 0 if ok, -ENOENT if the property did not exist, -EINVAL if the
347 * format of the property was invalid, -ENXIO if the requested
348 * address type was not found
350 int fdtdec_get_pci_addr(const void *blob, int node, enum fdt_pci_space type,
351 const char *prop_name, struct fdt_pci_addr *addr);
354 * Look at the compatible property of a device node that represents a PCI
355 * device and extract pci vendor id and device id from it.
357 * @param blob FDT blob
358 * @param node node to examine
359 * @param vendor vendor id of the pci device
360 * @param device device id of the pci device
361 * @return 0 if ok, negative on error
363 int fdtdec_get_pci_vendev(const void *blob, int node,
364 u16 *vendor, u16 *device);
367 * Look at the pci address of a device node that represents a PCI device
368 * and parse the bus, device and function number from it. For some cases
369 * like the bus number encoded in reg property is not correct after pci
370 * enumeration, this function looks through the node's compatible strings
371 * to get these numbers extracted instead.
373 * @param blob FDT blob
374 * @param node node to examine
375 * @param addr pci address in the form of fdt_pci_addr
376 * @param bdf returns bus, device, function triplet
377 * @return 0 if ok, negative on error
379 int fdtdec_get_pci_bdf(const void *blob, int node,
380 struct fdt_pci_addr *addr, pci_dev_t *bdf);
383 * Look at the pci address of a device node that represents a PCI device
384 * and return base address of the pci device's registers.
386 * @param blob FDT blob
387 * @param node node to examine
388 * @param addr pci address in the form of fdt_pci_addr
389 * @param bar returns base address of the pci device's registers
390 * @return 0 if ok, negative on error
392 int fdtdec_get_pci_bar32(const void *blob, int node,
393 struct fdt_pci_addr *addr, u32 *bar);
396 * Look up a 32-bit integer property in a node and return it. The property
397 * must have at least 4 bytes of data. The value of the first cell is
400 * @param blob FDT blob
401 * @param node node to examine
402 * @param prop_name name of property to find
403 * @param default_val default value to return if the property is not found
404 * @return integer value, if found, or default_val if not
406 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
410 * Get a variable-sized number from a property
412 * This reads a number from one or more cells.
414 * @param ptr Pointer to property
415 * @param cells Number of cells containing the number
416 * @return the value in the cells
418 u64 fdtdec_get_number(const fdt32_t *ptr, unsigned int cells);
421 * Look up a 64-bit integer property in a node and return it. The property
422 * must have at least 8 bytes of data (2 cells). The first two cells are
423 * concatenated to form a 8 bytes value, where the first cell is top half and
424 * the second cell is bottom half.
426 * @param blob FDT blob
427 * @param node node to examine
428 * @param prop_name name of property to find
429 * @param default_val default value to return if the property is not found
430 * @return integer value, if found, or default_val if not
432 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
433 uint64_t default_val);
436 * Checks whether a node is enabled.
437 * This looks for a 'status' property. If this exists, then returns 1 if
438 * the status is 'ok' and 0 otherwise. If there is no status property,
439 * it returns 1 on the assumption that anything mentioned should be enabled
442 * @param blob FDT blob
443 * @param node node to examine
444 * @return integer value 0 (not enabled) or 1 (enabled)
446 int fdtdec_get_is_enabled(const void *blob, int node);
449 * Make sure we have a valid fdt available to control U-Boot.
451 * If not, a message is printed to the console if the console is ready.
453 * @return 0 if all ok, -1 if not
455 int fdtdec_prepare_fdt(void);
458 * Checks that we have a valid fdt available to control U-Boot.
460 * However, if not then for the moment nothing is done, since this function
461 * is called too early to panic().
465 int fdtdec_check_fdt(void);
468 * Find the nodes for a peripheral and return a list of them in the correct
469 * order. This is used to enumerate all the peripherals of a certain type.
471 * To use this, optionally set up a /aliases node with alias properties for
472 * a peripheral. For example, for usb you could have:
475 * usb0 = "/ehci@c5008000";
476 * usb1 = "/ehci@c5000000";
479 * Pass "usb" as the name to this function and will return a list of two
480 * nodes offsets: /ehci@c5008000 and ehci@c5000000.
482 * All nodes returned will match the compatible ID, as it is assumed that
483 * all peripherals use the same driver.
485 * If no alias node is found, then the node list will be returned in the
486 * order found in the fdt. If the aliases mention a node which doesn't
487 * exist, then this will be ignored. If nodes are found with no aliases,
488 * they will be added in any order.
490 * If there is a gap in the aliases, then this function return a 0 node at
491 * that position. The return value will also count these gaps.
493 * This function checks node properties and will not return nodes which are
494 * marked disabled (status = "disabled").
496 * @param blob FDT blob to use
497 * @param name Root name of alias to search for
498 * @param id Compatible ID to look for
499 * @param node_list Place to put list of found nodes
500 * @param maxcount Maximum number of nodes to find
501 * @return number of nodes found on success, FTD_ERR_... on error
503 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
504 enum fdt_compat_id id, int *node_list, int maxcount);
507 * This function is similar to fdtdec_find_aliases_for_id() except that it
508 * adds to the node_list that is passed in. Any 0 elements are considered
509 * available for allocation - others are considered already used and are
512 * You can use this by calling fdtdec_find_aliases_for_id() with an
513 * uninitialised array, then setting the elements that are returned to -1,
514 * say, then calling this function, perhaps with a different compat id.
515 * Any elements you get back that are >0 are new nodes added by the call
518 * Note that if you have some nodes with aliases and some without, you are
519 * sailing close to the wind. The call to fdtdec_find_aliases_for_id() with
520 * one compat_id may fill in positions for which you have aliases defined
521 * for another compat_id. When you later call *this* function with the second
522 * compat_id, the alias positions may already be used. A debug warning may
523 * be generated in this case, but it is safest to define aliases for all
524 * nodes when you care about the ordering.
526 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
527 enum fdt_compat_id id, int *node_list, int maxcount);
530 * Get the alias sequence number of a node
532 * This works out whether a node is pointed to by an alias, and if so, the
533 * sequence number of that alias. Aliases are of the form <base><num> where
534 * <num> is the sequence number. For example spi2 would be sequence number
537 * @param blob Device tree blob (if NULL, then error is returned)
538 * @param base Base name for alias (before the underscore)
539 * @param node Node to look up
540 * @param seqp This is set to the sequence number if one is found,
541 * but otherwise the value is left alone
542 * @return 0 if a sequence was found, -ve if not
544 int fdtdec_get_alias_seq(const void *blob, const char *base, int node,
548 * Get the offset of the given chosen node
550 * This looks up a property in /chosen containing the path to another node,
551 * then finds the offset of that node.
553 * @param blob Device tree blob (if NULL, then error is returned)
554 * @param name Property name, e.g. "stdout-path"
555 * @return Node offset referred to by that chosen node, or -ve FDT_ERR_...
557 int fdtdec_get_chosen_node(const void *blob, const char *name);
560 * Get the name for a compatible ID
562 * @param id Compatible ID to look for
563 * @return compatible string for that id
565 const char *fdtdec_get_compatible(enum fdt_compat_id id);
567 /* Look up a phandle and follow it to its node. Then return the offset
570 * @param blob FDT blob
571 * @param node node to examine
572 * @param prop_name name of property to find
573 * @return node offset if found, -ve error code on error
575 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name);
578 * Look up a property in a node and return its contents in an integer
579 * array of given length. The property must have at least enough data for
580 * the array (4*count bytes). It may have more, but this will be ignored.
582 * @param blob FDT blob
583 * @param node node to examine
584 * @param prop_name name of property to find
585 * @param array array to fill with data
586 * @param count number of array elements
587 * @return 0 if ok, or -FDT_ERR_NOTFOUND if the property is not found,
588 * or -FDT_ERR_BADLAYOUT if not enough data
590 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
591 u32 *array, int count);
594 * Look up a property in a node and return its contents in an integer
595 * array of given length. The property must exist but may have less data that
596 * expected (4*count bytes). It may have more, but this will be ignored.
598 * @param blob FDT blob
599 * @param node node to examine
600 * @param prop_name name of property to find
601 * @param array array to fill with data
602 * @param count number of array elements
603 * @return number of array elements if ok, or -FDT_ERR_NOTFOUND if the
604 * property is not found
606 int fdtdec_get_int_array_count(const void *blob, int node,
607 const char *prop_name, u32 *array, int count);
610 * Look up a property in a node and return a pointer to its contents as a
611 * unsigned int array of given length. The property must have at least enough
612 * data for the array ('count' cells). It may have more, but this will be
613 * ignored. The data is not copied.
615 * Note that you must access elements of the array with fdt32_to_cpu(),
616 * since the elements will be big endian even on a little endian machine.
618 * @param blob FDT blob
619 * @param node node to examine
620 * @param prop_name name of property to find
621 * @param count number of array elements
622 * @return pointer to array if found, or NULL if the property is not
623 * found or there is not enough data
625 const u32 *fdtdec_locate_array(const void *blob, int node,
626 const char *prop_name, int count);
629 * Look up a boolean property in a node and return it.
631 * A boolean properly is true if present in the device tree and false if not
632 * present, regardless of its value.
634 * @param blob FDT blob
635 * @param node node to examine
636 * @param prop_name name of property to find
637 * @return 1 if the properly is present; 0 if it isn't present
639 int fdtdec_get_bool(const void *blob, int node, const char *prop_name);
642 * Look in the FDT for a config item with the given name and return its value
643 * as a 32-bit integer. The property must have at least 4 bytes of data. The
644 * value of the first cell is returned.
646 * @param blob FDT blob to use
647 * @param prop_name Node property name
648 * @param default_val default value to return if the property is not found
649 * @return integer value, if found, or default_val if not
651 int fdtdec_get_config_int(const void *blob, const char *prop_name,
655 * Look in the FDT for a config item with the given name
656 * and return whether it exists.
658 * @param blob FDT blob
659 * @param prop_name property name to look up
660 * @return 1, if it exists, or 0 if not
662 int fdtdec_get_config_bool(const void *blob, const char *prop_name);
665 * Look in the FDT for a config item with the given name and return its value
668 * @param blob FDT blob
669 * @param prop_name property name to look up
670 * @returns property string, NULL on error.
672 char *fdtdec_get_config_string(const void *blob, const char *prop_name);
675 * Look up a property in a node and return its contents in a byte
676 * array of given length. The property must have at least enough data for
677 * the array (count bytes). It may have more, but this will be ignored.
679 * @param blob FDT blob
680 * @param node node to examine
681 * @param prop_name name of property to find
682 * @param array array to fill with data
683 * @param count number of array elements
684 * @return 0 if ok, or -FDT_ERR_MISSING if the property is not found,
685 * or -FDT_ERR_BADLAYOUT if not enough data
687 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
688 u8 *array, int count);
691 * Look up a property in a node and return a pointer to its contents as a
692 * byte array of given length. The property must have at least enough data
693 * for the array (count bytes). It may have more, but this will be ignored.
694 * The data is not copied.
696 * @param blob FDT blob
697 * @param node node to examine
698 * @param prop_name name of property to find
699 * @param count number of array elements
700 * @return pointer to byte array if found, or NULL if the property is not
701 * found or there is not enough data
703 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
704 const char *prop_name, int count);
707 * Look up a property in a node which contains a memory region address and
708 * size. Then return a pointer to this address.
710 * The property must hold one address with a length. This is only tested on
713 * @param blob FDT blob
714 * @param node node to examine
715 * @param prop_name name of property to find
716 * @param basep Returns base address of region
717 * @param size Returns size of region
718 * @return 0 if ok, -1 on error (property not found)
720 int fdtdec_decode_region(const void *blob, int node, const char *prop_name,
721 fdt_addr_t *basep, fdt_size_t *sizep);
723 enum fmap_compress_t {
734 /* A flash map entry, containing an offset and length */
738 uint32_t used; /* Number of bytes used in region */
739 enum fmap_compress_t compress_algo; /* Compression type */
740 enum fmap_hash_t hash_algo; /* Hash algorithm */
741 const uint8_t *hash; /* Hash value */
742 int hash_size; /* Hash size */
746 * Read a flash entry from the fdt
748 * @param blob FDT blob
749 * @param node Offset of node to read
750 * @param name Name of node being read
751 * @param entry Place to put offset and size of this node
752 * @return 0 if ok, -ve on error
754 int fdtdec_read_fmap_entry(const void *blob, int node, const char *name,
755 struct fmap_entry *entry);
758 * Obtain an indexed resource from a device property.
760 * @param fdt FDT blob
761 * @param node node to examine
762 * @param property name of the property to parse
763 * @param index index of the resource to retrieve
764 * @param res returns the resource
765 * @return 0 if ok, negative on error
767 int fdt_get_resource(const void *fdt, int node, const char *property,
768 unsigned int index, struct fdt_resource *res);
771 * Obtain a named resource from a device property.
773 * Look up the index of the name in a list of strings and return the resource
776 * @param fdt FDT blob
777 * @param node node to examine
778 * @param property name of the property to parse
779 * @param prop_names name of the property containing the list of names
780 * @param name the name of the entry to look up
781 * @param res returns the resource
783 int fdt_get_named_resource(const void *fdt, int node, const char *property,
784 const char *prop_names, const char *name,
785 struct fdt_resource *res);
788 * Decode a named region within a memory bank of a given type.
790 * This function handles selection of a memory region. The region is
791 * specified as an offset/size within a particular type of memory.
793 * The properties used are:
795 * <mem_type>-memory<suffix> for the name of the memory bank
796 * <mem_type>-offset<suffix> for the offset in that bank
798 * The property value must have an offset and a size. The function checks
799 * that the region is entirely within the memory bank.5
801 * @param blob FDT blob
802 * @param node Node containing the properties (-1 for /config)
803 * @param mem_type Type of memory to use, which is a name, such as
804 * "u-boot" or "kernel".
805 * @param suffix String to append to the memory/offset
807 * @param basep Returns base of region
808 * @param sizep Returns size of region
809 * @return 0 if OK, -ive on error
811 int fdtdec_decode_memory_region(const void *blob, int node,
812 const char *mem_type, const char *suffix,
813 fdt_addr_t *basep, fdt_size_t *sizep);
815 /* Display timings from linux include/video/display_timing.h */
817 DISPLAY_FLAGS_HSYNC_LOW = 1 << 0,
818 DISPLAY_FLAGS_HSYNC_HIGH = 1 << 1,
819 DISPLAY_FLAGS_VSYNC_LOW = 1 << 2,
820 DISPLAY_FLAGS_VSYNC_HIGH = 1 << 3,
822 /* data enable flag */
823 DISPLAY_FLAGS_DE_LOW = 1 << 4,
824 DISPLAY_FLAGS_DE_HIGH = 1 << 5,
825 /* drive data on pos. edge */
826 DISPLAY_FLAGS_PIXDATA_POSEDGE = 1 << 6,
827 /* drive data on neg. edge */
828 DISPLAY_FLAGS_PIXDATA_NEGEDGE = 1 << 7,
829 DISPLAY_FLAGS_INTERLACED = 1 << 8,
830 DISPLAY_FLAGS_DOUBLESCAN = 1 << 9,
831 DISPLAY_FLAGS_DOUBLECLK = 1 << 10,
835 * A single signal can be specified via a range of minimal and maximal values
836 * with a typical value, that lies somewhere inbetween.
838 struct timing_entry {
845 * Single "mode" entry. This describes one set of signal timings a display can
846 * have in one setting. This struct can later be converted to struct videomode
847 * (see include/video/videomode.h). As each timing_entry can be defined as a
848 * range, one struct display_timing may become multiple struct videomodes.
850 * Example: hsync active high, vsync active low
853 * Video ______________________XXXXXXXXXXXXXXXXXXXXXX_____________________
854 * |<- sync ->|<- back ->|<----- active ----->|<- front ->|<- sync..
855 * | | porch | | porch |
857 * HSync _|¯¯¯¯¯¯¯¯¯¯|___________________________________________|¯¯¯¯¯¯¯¯¯
859 * VSync ¯|__________|¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯|_________
861 struct display_timing {
862 struct timing_entry pixelclock;
864 struct timing_entry hactive; /* hor. active video */
865 struct timing_entry hfront_porch; /* hor. front porch */
866 struct timing_entry hback_porch; /* hor. back porch */
867 struct timing_entry hsync_len; /* hor. sync len */
869 struct timing_entry vactive; /* ver. active video */
870 struct timing_entry vfront_porch; /* ver. front porch */
871 struct timing_entry vback_porch; /* ver. back porch */
872 struct timing_entry vsync_len; /* ver. sync len */
874 enum display_flags flags; /* display flags */
878 * fdtdec_decode_display_timing() - decode display timings
880 * Decode display timings from the supplied 'display-timings' node.
881 * See doc/device-tree-bindings/video/display-timing.txt for binding
884 * @param blob FDT blob
885 * @param node 'display-timing' node containing the timing subnodes
886 * @param index Index number to read (0=first timing subnode)
887 * @param config Place to put timings
888 * @return 0 if OK, -FDT_ERR_NOTFOUND if not found
890 int fdtdec_decode_display_timing(const void *blob, int node, int index,
891 struct display_timing *config);
893 * Set up the device tree ready for use
895 int fdtdec_setup(void);