u-boot/include/fdtdec.h

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/*
* 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 <libfdt.h>
/*
* 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;
};
/**
* Compat types that we know about and for which we might have drivers.
* Each is named COMPAT_<dir>_<filename> where <dir> 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_COUNT,
};
fdt: Add basic support for decoding GPIO definitions This adds some support into fdtdec for reading GPIO definitions from the fdt. We permit up to FDT_GPIO_MAX GPIOs in the system. Each GPIO is of the form: gpio-function-name = <phandle gpio_num flags>; where: phandle is a pointer to the GPIO node gpio_num is the number of the GPIO (0 to 223) flags is a flag, as follows: bit meaning 0 0=polarity normal, 1=active low (inverted) An example is: enable-propounder-gpios = <&gpio 43 0>; which means that GPIO 43 is used to enable the propounder (setting the GPIO high), or that you can detect that the propounder is enabled by checking if the GPIO is high (the fdt does not indicate input/output). Two main functions are provided: fdtdec_decode_gpio() reads a GPIO property from an fdt node and decodes it into a structure. fdtdec_setup_gpio() sets up the GPIO by calling gpio_request for you. Both functions can cope with the property being missing, which is taken to mean that that GPIO function is not available or is not needed. [For reference, from Stephen Warren <swarren@nvidia.com>. It may be that we add this extra complexity later if needed: The correct way to parse such a GPIO property in general is: * Read the first cell. * Find the node referenced by the phandle (the controller). * Ensure property gpio-controller is present in the controller node. * Read property #gpio-cells from the controller node. * Extract #gpio-cells from the original property. * Keep processing more cells from the original property; there may be multiple GPIOs listed. According to the binding documentation in the Linux kernel, Samsung Exynos4 doesn't use this format, and while all other chips do have a flags cell, about 50% of the controllers indicate the cell is unused. ] Signed-off-by: Simon Glass <sjg@chromium.org> Signed-off-by: Tom Warren <twarren@nvidia.com>
2012-02-27 10:52:36 +00:00
/* 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/<name>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 <base><num> where
* <num> 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 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);
fdt: Add basic support for decoding GPIO definitions This adds some support into fdtdec for reading GPIO definitions from the fdt. We permit up to FDT_GPIO_MAX GPIOs in the system. Each GPIO is of the form: gpio-function-name = <phandle gpio_num flags>; where: phandle is a pointer to the GPIO node gpio_num is the number of the GPIO (0 to 223) flags is a flag, as follows: bit meaning 0 0=polarity normal, 1=active low (inverted) An example is: enable-propounder-gpios = <&gpio 43 0>; which means that GPIO 43 is used to enable the propounder (setting the GPIO high), or that you can detect that the propounder is enabled by checking if the GPIO is high (the fdt does not indicate input/output). Two main functions are provided: fdtdec_decode_gpio() reads a GPIO property from an fdt node and decodes it into a structure. fdtdec_setup_gpio() sets up the GPIO by calling gpio_request for you. Both functions can cope with the property being missing, which is taken to mean that that GPIO function is not available or is not needed. [For reference, from Stephen Warren <swarren@nvidia.com>. It may be that we add this extra complexity later if needed: The correct way to parse such a GPIO property in general is: * Read the first cell. * Find the node referenced by the phandle (the controller). * Ensure property gpio-controller is present in the controller node. * Read property #gpio-cells from the controller node. * Extract #gpio-cells from the original property. * Keep processing more cells from the original property; there may be multiple GPIOs listed. According to the binding documentation in the Linux kernel, Samsung Exynos4 doesn't use this format, and while all other chips do have a flags cell, about 50% of the controllers indicate the cell is unused. ] Signed-off-by: Simon Glass <sjg@chromium.org> Signed-off-by: Tom Warren <twarren@nvidia.com>
2012-02-27 10:52:36 +00:00
/**
* 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);
fdt: Add basic support for decoding GPIO definitions This adds some support into fdtdec for reading GPIO definitions from the fdt. We permit up to FDT_GPIO_MAX GPIOs in the system. Each GPIO is of the form: gpio-function-name = <phandle gpio_num flags>; where: phandle is a pointer to the GPIO node gpio_num is the number of the GPIO (0 to 223) flags is a flag, as follows: bit meaning 0 0=polarity normal, 1=active low (inverted) An example is: enable-propounder-gpios = <&gpio 43 0>; which means that GPIO 43 is used to enable the propounder (setting the GPIO high), or that you can detect that the propounder is enabled by checking if the GPIO is high (the fdt does not indicate input/output). Two main functions are provided: fdtdec_decode_gpio() reads a GPIO property from an fdt node and decodes it into a structure. fdtdec_setup_gpio() sets up the GPIO by calling gpio_request for you. Both functions can cope with the property being missing, which is taken to mean that that GPIO function is not available or is not needed. [For reference, from Stephen Warren <swarren@nvidia.com>. It may be that we add this extra complexity later if needed: The correct way to parse such a GPIO property in general is: * Read the first cell. * Find the node referenced by the phandle (the controller). * Ensure property gpio-controller is present in the controller node. * Read property #gpio-cells from the controller node. * Extract #gpio-cells from the original property. * Keep processing more cells from the original property; there may be multiple GPIOs listed. According to the binding documentation in the Linux kernel, Samsung Exynos4 doesn't use this format, and while all other chips do have a flags cell, about 50% of the controllers indicate the cell is unused. ] Signed-off-by: Simon Glass <sjg@chromium.org> Signed-off-by: Tom Warren <twarren@nvidia.com>
2012-02-27 10:52:36 +00:00
/**
* 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);
#endif