/* * Copyright (c) 2011 The Chromium OS Authors. * SPDX-License-Identifier: GPL-2.0+ */ #ifndef __fdtdec_h #define __fdtdec_h /* * This file contains convenience functions for decoding useful and * enlightening information from FDTs. It is intended to be used by device * drivers and board-specific code within U-Boot. It aims to reduce the * amount of FDT munging required within U-Boot itself, so that driver code * changes to support FDT are minimized. */ #include /* * A typedef for a physical address. Note that fdt data is always big * endian even on a litle endian machine. */ #ifdef CONFIG_PHYS_64BIT typedef u64 fdt_addr_t; typedef u64 fdt_size_t; #define FDT_ADDR_T_NONE (-1ULL) #define fdt_addr_to_cpu(reg) be64_to_cpu(reg) #define fdt_size_to_cpu(reg) be64_to_cpu(reg) #else typedef u32 fdt_addr_t; typedef u32 fdt_size_t; #define FDT_ADDR_T_NONE (-1U) #define fdt_addr_to_cpu(reg) be32_to_cpu(reg) #define fdt_size_to_cpu(reg) be32_to_cpu(reg) #endif /* Information obtained about memory from the FDT */ struct fdt_memory { fdt_addr_t start; fdt_addr_t end; }; /* * Information about a resource. start is the first address of the resource * and end is the last address (inclusive). The length of the resource will * be equal to: end - start + 1. */ struct fdt_resource { fdt_addr_t start; fdt_addr_t end; }; /** * Compute the size of a resource. * * @param res the resource to operate on * @return the size of the resource */ static inline fdt_size_t fdt_resource_size(const struct fdt_resource *res) { return res->end - res->start + 1; } /** * Compat types that we know about and for which we might have drivers. * Each is named COMPAT__ where is the directory * within drivers. */ enum fdt_compat_id { COMPAT_UNKNOWN, COMPAT_NVIDIA_TEGRA20_USB, /* Tegra20 USB port */ COMPAT_NVIDIA_TEGRA30_USB, /* Tegra30 USB port */ COMPAT_NVIDIA_TEGRA114_USB, /* Tegra114 USB port */ COMPAT_NVIDIA_TEGRA114_I2C, /* Tegra114 I2C w/single clock source */ COMPAT_NVIDIA_TEGRA20_I2C, /* Tegra20 i2c */ COMPAT_NVIDIA_TEGRA20_DVC, /* Tegra20 dvc (really just i2c) */ COMPAT_NVIDIA_TEGRA20_EMC, /* Tegra20 memory controller */ COMPAT_NVIDIA_TEGRA20_EMC_TABLE, /* Tegra20 memory timing table */ COMPAT_NVIDIA_TEGRA20_KBC, /* Tegra20 Keyboard */ COMPAT_NVIDIA_TEGRA20_NAND, /* Tegra2 NAND controller */ COMPAT_NVIDIA_TEGRA20_PWM, /* Tegra 2 PWM controller */ COMPAT_NVIDIA_TEGRA20_DC, /* Tegra 2 Display controller */ COMPAT_NVIDIA_TEGRA124_SDMMC, /* Tegra124 SDMMC controller */ COMPAT_NVIDIA_TEGRA30_SDMMC, /* Tegra30 SDMMC controller */ COMPAT_NVIDIA_TEGRA20_SDMMC, /* Tegra20 SDMMC controller */ COMPAT_NVIDIA_TEGRA20_SFLASH, /* Tegra 2 SPI flash controller */ COMPAT_NVIDIA_TEGRA20_SLINK, /* Tegra 2 SPI SLINK controller */ COMPAT_NVIDIA_TEGRA114_SPI, /* Tegra 114 SPI controller */ COMPAT_SMSC_LAN9215, /* SMSC 10/100 Ethernet LAN9215 */ COMPAT_SAMSUNG_EXYNOS5_SROMC, /* Exynos5 SROMC */ COMPAT_SAMSUNG_S3C2440_I2C, /* Exynos I2C Controller */ COMPAT_SAMSUNG_EXYNOS5_SOUND, /* Exynos Sound */ COMPAT_WOLFSON_WM8994_CODEC, /* Wolfson WM8994 Sound Codec */ COMPAT_SAMSUNG_EXYNOS_SPI, /* Exynos SPI */ COMPAT_GOOGLE_CROS_EC, /* Google CROS_EC Protocol */ COMPAT_GOOGLE_CROS_EC_KEYB, /* Google CROS_EC Keyboard */ COMPAT_SAMSUNG_EXYNOS_EHCI, /* Exynos EHCI controller */ COMPAT_SAMSUNG_EXYNOS5_XHCI, /* Exynos5 XHCI controller */ COMPAT_SAMSUNG_EXYNOS_USB_PHY, /* Exynos phy controller for usb2.0 */ COMPAT_SAMSUNG_EXYNOS5_USB3_PHY,/* Exynos phy controller for usb3.0 */ COMPAT_SAMSUNG_EXYNOS_TMU, /* Exynos TMU */ COMPAT_SAMSUNG_EXYNOS_FIMD, /* Exynos Display controller */ COMPAT_SAMSUNG_EXYNOS_MIPI_DSI, /* Exynos mipi dsi */ COMPAT_SAMSUNG_EXYNOS5_DP, /* Exynos Display port controller */ COMPAT_SAMSUNG_EXYNOS_DWMMC, /* Exynos DWMMC controller */ COMPAT_SAMSUNG_EXYNOS_MMC, /* Exynos MMC controller */ COMPAT_SAMSUNG_EXYNOS_SERIAL, /* Exynos UART */ COMPAT_MAXIM_MAX77686_PMIC, /* MAX77686 PMIC */ COMPAT_GENERIC_SPI_FLASH, /* Generic SPI Flash chip */ COMPAT_MAXIM_98095_CODEC, /* MAX98095 Codec */ COMPAT_INFINEON_SLB9635_TPM, /* Infineon SLB9635 TPM */ COMPAT_INFINEON_SLB9645_TPM, /* Infineon SLB9645 TPM */ COMPAT_SAMSUNG_EXYNOS5_I2C, /* Exynos5 High Speed I2C Controller */ COMPAT_SANDBOX_HOST_EMULATION, /* Sandbox emulation of a function */ COMPAT_SANDBOX_LCD_SDL, /* Sandbox LCD emulation with SDL */ COMPAT_TI_TPS65090, /* Texas Instrument TPS65090 */ COMPAT_NXP_PTN3460, /* NXP PTN3460 DP/LVDS bridge */ COMPAT_SAMSUNG_EXYNOS_SYSMMU, /* Exynos sysmmu */ COMPAT_PARADE_PS8625, /* Parade PS8622 EDP->LVDS bridge */ COMPAT_INTEL_LPC, /* Intel Low Pin Count I/F */ COMPAT_INTEL_MICROCODE, /* Intel microcode update */ COMPAT_MEMORY_SPD, /* Memory SPD information */ COMPAT_INTEL_PANTHERPOINT_AHCI, /* Intel Pantherpoint AHCI */ COMPAT_INTEL_MODEL_206AX, /* Intel Model 206AX CPU */ COMPAT_COUNT, }; /* GPIOs are numbered from 0 */ enum { FDT_GPIO_NONE = -1U, /* an invalid GPIO used to end our list */ FDT_GPIO_ACTIVE_LOW = 1 << 0, /* input is active low (else high) */ }; /* This is the state of a GPIO pin as defined by the fdt */ struct fdt_gpio_state { const char *name; /* name of the fdt property defining this */ uint gpio; /* GPIO number, or FDT_GPIO_NONE if none */ u8 flags; /* FDT_GPIO_... flags */ }; /* This tells us whether a fdt_gpio_state record is valid or not */ #define fdt_gpio_isvalid(x) ((x)->gpio != FDT_GPIO_NONE) /** * Read the GPIO taking into account the polarity of the pin. * * @param gpio pointer to the decoded gpio * @return value of the gpio if successful, < 0 if unsuccessful */ int fdtdec_get_gpio(struct fdt_gpio_state *gpio); /** * Write the GPIO taking into account the polarity of the pin. * * @param gpio pointer to the decoded gpio * @return 0 if successful */ int fdtdec_set_gpio(struct fdt_gpio_state *gpio, int val); /** * Find the next numbered alias for a peripheral. This is used to enumerate * all the peripherals of a certain type. * * Do the first call with *upto = 0. Assuming /aliases/0 exists then * this function will return a pointer to the node the alias points to, and * then update *upto to 1. Next time you call this function, the next node * will be returned. * * All nodes returned will match the compatible ID, as it is assumed that * all peripherals use the same driver. * * @param blob FDT blob to use * @param name Root name of alias to search for * @param id Compatible ID to look for * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more */ int fdtdec_next_alias(const void *blob, const char *name, enum fdt_compat_id id, int *upto); /** * Find the compatible ID for a given node. * * Generally each node has at least one compatible string attached to it. * This function looks through our list of known compatible strings and * returns the corresponding ID which matches the compatible string. * * @param blob FDT blob to use * @param node Node containing compatible string to find * @return compatible ID, or COMPAT_UNKNOWN if we cannot find a match */ enum fdt_compat_id fdtdec_lookup(const void *blob, int node); /** * Find the next compatible node for a peripheral. * * Do the first call with node = 0. This function will return a pointer to * the next compatible node. Next time you call this function, pass the * value returned, and the next node will be provided. * * @param blob FDT blob to use * @param node Start node for search * @param id Compatible ID to look for (enum fdt_compat_id) * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more */ int fdtdec_next_compatible(const void *blob, int node, enum fdt_compat_id id); /** * Find the next compatible subnode for a peripheral. * * Do the first call with node set to the parent and depth = 0. This * function will return the offset of the next compatible node. Next time * you call this function, pass the node value returned last time, with * depth unchanged, and the next node will be provided. * * @param blob FDT blob to use * @param node Start node for search * @param id Compatible ID to look for (enum fdt_compat_id) * @param depthp Current depth (set to 0 before first call) * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more */ int fdtdec_next_compatible_subnode(const void *blob, int node, enum fdt_compat_id id, int *depthp); /** * Look up an address property in a node and return it as an address. * The property must hold either one address with no trailing data or * one address with a length. This is only tested on 32-bit machines. * * @param blob FDT blob * @param node node to examine * @param prop_name name of property to find * @return address, if found, or FDT_ADDR_T_NONE if not */ fdt_addr_t fdtdec_get_addr(const void *blob, int node, const char *prop_name); /** * Look up an address property in a node and return it as an address. * The property must hold one address with a length. This is only tested * on 32-bit machines. * * @param blob FDT blob * @param node node to examine * @param prop_name name of property to find * @return address, if found, or FDT_ADDR_T_NONE if not */ fdt_addr_t fdtdec_get_addr_size(const void *blob, int node, const char *prop_name, fdt_size_t *sizep); /** * Look up a 32-bit integer property in a node and return it. The property * must have at least 4 bytes of data. The value of the first cell is * returned. * * @param blob FDT blob * @param node node to examine * @param prop_name name of property to find * @param default_val default value to return if the property is not found * @return integer value, if found, or default_val if not */ s32 fdtdec_get_int(const void *blob, int node, const char *prop_name, s32 default_val); /** * Look up a 64-bit integer property in a node and return it. The property * must have at least 8 bytes of data (2 cells). The first two cells are * concatenated to form a 8 bytes value, where the first cell is top half and * the second cell is bottom half. * * @param blob FDT blob * @param node node to examine * @param prop_name name of property to find * @param default_val default value to return if the property is not found * @return integer value, if found, or default_val if not */ uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name, uint64_t default_val); /** * Checks whether a node is enabled. * This looks for a 'status' property. If this exists, then returns 1 if * the status is 'ok' and 0 otherwise. If there is no status property, * it returns 1 on the assumption that anything mentioned should be enabled * by default. * * @param blob FDT blob * @param node node to examine * @return integer value 0 (not enabled) or 1 (enabled) */ int fdtdec_get_is_enabled(const void *blob, int node); /** * Make sure we have a valid fdt available to control U-Boot. * * If not, a message is printed to the console if the console is ready. * * @return 0 if all ok, -1 if not */ int fdtdec_prepare_fdt(void); /** * Checks that we have a valid fdt available to control U-Boot. * However, if not then for the moment nothing is done, since this function * is called too early to panic(). * * @returns 0 */ int fdtdec_check_fdt(void); /** * Find the nodes for a peripheral and return a list of them in the correct * order. This is used to enumerate all the peripherals of a certain type. * * To use this, optionally set up a /aliases node with alias properties for * a peripheral. For example, for usb you could have: * * aliases { * usb0 = "/ehci@c5008000"; * usb1 = "/ehci@c5000000"; * }; * * Pass "usb" as the name to this function and will return a list of two * nodes offsets: /ehci@c5008000 and ehci@c5000000. * * All nodes returned will match the compatible ID, as it is assumed that * all peripherals use the same driver. * * If no alias node is found, then the node list will be returned in the * order found in the fdt. If the aliases mention a node which doesn't * exist, then this will be ignored. If nodes are found with no aliases, * they will be added in any order. * * If there is a gap in the aliases, then this function return a 0 node at * that position. The return value will also count these gaps. * * This function checks node properties and will not return nodes which are * marked disabled (status = "disabled"). * * @param blob FDT blob to use * @param name Root name of alias to search for * @param id Compatible ID to look for * @param node_list Place to put list of found nodes * @param maxcount Maximum number of nodes to find * @return number of nodes found on success, FTD_ERR_... on error */ int fdtdec_find_aliases_for_id(const void *blob, const char *name, enum fdt_compat_id id, int *node_list, int maxcount); /* * This function is similar to fdtdec_find_aliases_for_id() except that it * adds to the node_list that is passed in. Any 0 elements are considered * available for allocation - others are considered already used and are * skipped. * * You can use this by calling fdtdec_find_aliases_for_id() with an * uninitialised array, then setting the elements that are returned to -1, * say, then calling this function, perhaps with a different compat id. * Any elements you get back that are >0 are new nodes added by the call * to this function. * * Note that if you have some nodes with aliases and some without, you are * sailing close to the wind. The call to fdtdec_find_aliases_for_id() with * one compat_id may fill in positions for which you have aliases defined * for another compat_id. When you later call *this* function with the second * compat_id, the alias positions may already be used. A debug warning may * be generated in this case, but it is safest to define aliases for all * nodes when you care about the ordering. */ int fdtdec_add_aliases_for_id(const void *blob, const char *name, enum fdt_compat_id id, int *node_list, int maxcount); /** * Get the alias sequence number of a node * * This works out whether a node is pointed to by an alias, and if so, the * sequence number of that alias. Aliases are of the form where * is the sequence number. For example spi2 would be sequence number * 2. * * @param blob Device tree blob (if NULL, then error is returned) * @param base Base name for alias (before the underscore) * @param node Node to look up * @param seqp This is set to the sequence number if one is found, * but otherwise the value is left alone * @return 0 if a sequence was found, -ve if not */ int fdtdec_get_alias_seq(const void *blob, const char *base, int node, int *seqp); /** * Get the offset of the given alias node * * This looks up an alias in /aliases then finds the offset of that node. * * @param blob Device tree blob (if NULL, then error is returned) * @param name Alias name, e.g. "console" * @return Node offset referred to by that alias, or -ve FDT_ERR_... */ int fdtdec_get_alias_node(const void *blob, const char *name); /** * Get the offset of the given chosen node * * This looks up a property in /chosen containing the path to another node, * then finds the offset of that node. * * @param blob Device tree blob (if NULL, then error is returned) * @param name Property name, e.g. "stdout-path" * @return Node offset referred to by that chosen node, or -ve FDT_ERR_... */ int fdtdec_get_chosen_node(const void *blob, const char *name); /* * Get the name for a compatible ID * * @param id Compatible ID to look for * @return compatible string for that id */ const char *fdtdec_get_compatible(enum fdt_compat_id id); /* Look up a phandle and follow it to its node. Then return the offset * of that node. * * @param blob FDT blob * @param node node to examine * @param prop_name name of property to find * @return node offset if found, -ve error code on error */ int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name); /** * Look up a property in a node and return its contents in an integer * array of given length. The property must have at least enough data for * the array (4*count bytes). It may have more, but this will be ignored. * * @param blob FDT blob * @param node node to examine * @param prop_name name of property to find * @param array array to fill with data * @param count number of array elements * @return 0 if ok, or -FDT_ERR_NOTFOUND if the property is not found, * or -FDT_ERR_BADLAYOUT if not enough data */ int fdtdec_get_int_array(const void *blob, int node, const char *prop_name, u32 *array, int count); /** * Look up a property in a node and return its contents in an integer * array of given length. The property must exist but may have less data that * expected (4*count bytes). It may have more, but this will be ignored. * * @param blob FDT blob * @param node node to examine * @param prop_name name of property to find * @param array array to fill with data * @param count number of array elements * @return number of array elements if ok, or -FDT_ERR_NOTFOUND if the * property is not found */ int fdtdec_get_int_array_count(const void *blob, int node, const char *prop_name, u32 *array, int count); /** * Look up a property in a node and return a pointer to its contents as a * unsigned int array of given length. The property must have at least enough * data for the array ('count' cells). It may have more, but this will be * ignored. The data is not copied. * * Note that you must access elements of the array with fdt32_to_cpu(), * since the elements will be big endian even on a little endian machine. * * @param blob FDT blob * @param node node to examine * @param prop_name name of property to find * @param count number of array elements * @return pointer to array if found, or NULL if the property is not * found or there is not enough data */ const u32 *fdtdec_locate_array(const void *blob, int node, const char *prop_name, int count); /** * Look up a boolean property in a node and return it. * * A boolean properly is true if present in the device tree and false if not * present, regardless of its value. * * @param blob FDT blob * @param node node to examine * @param prop_name name of property to find * @return 1 if the properly is present; 0 if it isn't present */ int fdtdec_get_bool(const void *blob, int node, const char *prop_name); /** * Decode a single GPIOs from an FDT. * * If the property is not found, then the GPIO structure will still be * initialised, with gpio set to FDT_GPIO_NONE. This makes it easy to * provide optional GPIOs. * * @param blob FDT blob to use * @param node Node to look at * @param prop_name Node property name * @param gpio gpio elements to fill from FDT * @return 0 if ok, -FDT_ERR_NOTFOUND if the property is missing. */ int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name, struct fdt_gpio_state *gpio); /** * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no * terminating item. * * @param blob FDT blob to use * @param node Node to look at * @param prop_name Node property name * @param gpio Array of gpio elements to fill from FDT. This will be * untouched if either 0 or an error is returned * @param max_count Maximum number of elements allowed * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing. */ int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name, struct fdt_gpio_state *gpio, int max_count); /** * Set up a GPIO pin according to the provided gpio information. At present this * just requests the GPIO. * * If the gpio is FDT_GPIO_NONE, no action is taken. This makes it easy to * deal with optional GPIOs. * * @param gpio GPIO info to use for set up * @return 0 if all ok or gpio was FDT_GPIO_NONE; -1 on error */ int fdtdec_setup_gpio(struct fdt_gpio_state *gpio); /** * Look in the FDT for a config item with the given name and return its value * as a 32-bit integer. The property must have at least 4 bytes of data. The * value of the first cell is returned. * * @param blob FDT blob to use * @param prop_name Node property name * @param default_val default value to return if the property is not found * @return integer value, if found, or default_val if not */ int fdtdec_get_config_int(const void *blob, const char *prop_name, int default_val); /** * Look in the FDT for a config item with the given name * and return whether it exists. * * @param blob FDT blob * @param prop_name property name to look up * @return 1, if it exists, or 0 if not */ int fdtdec_get_config_bool(const void *blob, const char *prop_name); /** * Look in the FDT for a config item with the given name and return its value * as a string. * * @param blob FDT blob * @param prop_name property name to look up * @returns property string, NULL on error. */ char *fdtdec_get_config_string(const void *blob, const char *prop_name); /* * Look up a property in a node and return its contents in a byte * array of given length. The property must have at least enough data for * the array (count bytes). It may have more, but this will be ignored. * * @param blob FDT blob * @param node node to examine * @param prop_name name of property to find * @param array array to fill with data * @param count number of array elements * @return 0 if ok, or -FDT_ERR_MISSING if the property is not found, * or -FDT_ERR_BADLAYOUT if not enough data */ int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name, u8 *array, int count); /** * Look up a property in a node and return a pointer to its contents as a * byte array of given length. The property must have at least enough data * for the array (count bytes). It may have more, but this will be ignored. * The data is not copied. * * @param blob FDT blob * @param node node to examine * @param prop_name name of property to find * @param count number of array elements * @return pointer to byte array if found, or NULL if the property is not * found or there is not enough data */ const u8 *fdtdec_locate_byte_array(const void *blob, int node, const char *prop_name, int count); /** * Look up a property in a node which contains a memory region address and * size. Then return a pointer to this address. * * The property must hold one address with a length. This is only tested on * 32-bit machines. * * @param blob FDT blob * @param node node to examine * @param prop_name name of property to find * @param ptrp returns pointer to region, or NULL if no address * @param size returns size of region * @return 0 if ok, -1 on error (propery not found) */ int fdtdec_decode_region(const void *blob, int node, const char *prop_name, void **ptrp, size_t *size); /* A flash map entry, containing an offset and length */ struct fmap_entry { uint32_t offset; uint32_t length; }; /** * Read a flash entry from the fdt * * @param blob FDT blob * @param node Offset of node to read * @param name Name of node being read * @param entry Place to put offset and size of this node * @return 0 if ok, -ve on error */ int fdtdec_read_fmap_entry(const void *blob, int node, const char *name, struct fmap_entry *entry); /** * Obtain an indexed resource from a device property. * * @param fdt FDT blob * @param node node to examine * @param property name of the property to parse * @param index index of the resource to retrieve * @param res returns the resource * @return 0 if ok, negative on error */ int fdt_get_resource(const void *fdt, int node, const char *property, unsigned int index, struct fdt_resource *res); /** * Obtain a named resource from a device property. * * Look up the index of the name in a list of strings and return the resource * at that index. * * @param fdt FDT blob * @param node node to examine * @param property name of the property to parse * @param prop_names name of the property containing the list of names * @param name the name of the entry to look up * @param res returns the resource */ int fdt_get_named_resource(const void *fdt, int node, const char *property, const char *prop_names, const char *name, struct fdt_resource *res); /** * Look at the reg property of a device node that represents a PCI device * and parse the bus, device and function number from it. * * @param fdt FDT blob * @param node node to examine * @param bdf returns bus, device, function triplet * @return 0 if ok, negative on error */ int fdtdec_pci_get_bdf(const void *fdt, int node, int *bdf); #endif