RTEMS Flattened Device Tree. More...

#include <rtems.h>
#include <rtems/chain.h>

Data Structures
struct	rtems_fdt_handle

struct	rtems_fdt_address_map

Macros
#define	RTEMS_FDT_ERR_NOTFOUND 1

#define	RTEMS_FDT_ERR_EXISTS 2

#define	RTEMS_FDT_ERR_NOSPACE 3

#define	RTEMS_FDT_ERR_BADOFFSET 4

#define	RTEMS_FDT_ERR_BADPATH 5

#define	RTEMS_FDT_ERR_BADPHANDLE 6

#define	RTEMS_FDT_ERR_BADSTATE 7

#define	RTEMS_FDT_ERR_TRUNCATED 8

#define	RTEMS_FDT_ERR_BADMAGIC 9

#define	RTEMS_FDT_ERR_BADVERSION 10

#define	RTEMS_FDT_ERR_BADSTRUCTURE 11

#define	RTEMS_FDT_ERR_BADLAYOUT 12

#define	RTEMS_FDT_ERR_INTERNAL 13

#define	RTEMS_FDT_ERR_INVALID_HANDLE 100

#define	RTEMS_FDT_ERR_NO_MEMORY 101

#define	RTEMS_FDT_ERR_NOT_FOUND 102

#define	RTEMS_FDT_ERR_READ_FAIL 103

#define	RTEMS_FDT_ERR_REFERENCED 104

#define	RTEMS_FDT_ERR_BADLENGTH 105

#define	RTEMS_FDT_ERR_RTEMS_MIN 100

#define	RTEMS_FDT_ERR_MAX 105

Typedefs
typedef struct rtems_fdt_blob	rtems_fdt_blob

Functions
void	rtems_fdt_init_handle (rtems_fdt_handle *handle)

void	rtems_fdt_dup_handle (rtems_fdt_handle from, rtems_fdt_handle to)

void	rtems_fdt_release_handle (rtems_fdt_handle *handle)

bool	rtems_fdt_valid_handle (const rtems_fdt_handle *handle)

int	rtems_fdt_find_path_offset (rtems_fdt_handle handle, const char path)

int	rtems_fdt_load (const char const filename, rtems_fdt_handle handle)

int	rtems_fdt_register (const void blob, rtems_fdt_handle handle)

int	rtems_fdt_unload (rtems_fdt_handle *handle)

int	rtems_fdt_num_mem_rsv (rtems_fdt_handle *handle)

int	rtems_fdt_get_mem_rsv (rtems_fdt_handle handle, int n, uint64_t address, uint64_t *size)

int	rtems_fdt_subnode_offset_namelen (rtems_fdt_handle handle, int parentoffset, const char const name, int namelen)

int	rtems_fdt_subnode_offset (rtems_fdt_handle handle, int parentoffset, const char const name)

int	rtems_fdt_path_offset (rtems_fdt_handle handle, const char path)

const char *	rtems_fdt_get_name (rtems_fdt_handle handle, int nodeoffset, int length)

int	rtems_fdt_first_prop_offset (rtems_fdt_handle *handle, int nodeoffset)

int	rtems_fdt_next_prop_offset (rtems_fdt_handle *handle, int propoffset)

const void *	rtems_fdt_getprop_by_offset (rtems_fdt_handle handle, int propoffset, const char name, int length)

const void *	rtems_fdt_getprop_namelen (rtems_fdt_handle handle, int nodeoffset, const char const name, int namelen, int *length)

const void *	rtems_fdt_getprop (rtems_fdt_handle handle, int nodeoffset, const char const name, int *length)

uint32_t	rtems_fdt_get_phandle (rtems_fdt_handle *handle, int nodeoffset)

const char *	rtems_fdt_get_alias_namelen (rtems_fdt_handle handle, const char const name, int namelen)

const char *	rtems_fdt_get_alias (rtems_fdt_handle handle, const char name)

int	rtems_fdt_get_path (rtems_fdt_handle handle, int nodeoffset, char buf, int buflen)

int	rtems_fdt_supernode_atdepth_offset (rtems_fdt_handle handle, int nodeoffset, int supernodedepth, int nodedepth)

int	rtems_fdt_node_depth (rtems_fdt_handle *handle, int nodeoffset)

int	rtems_fdt_parent_offset (rtems_fdt_handle *handle, int nodeoffset)

int	rtems_fdt_node_offset_by_prop_value (rtems_fdt_handle handle, int startoffset, const char const propname, const void *propval, int proplen)

int	rtems_fdt_node_offset_by_phandle (rtems_fdt_handle *handle, uint32_t phandle)

int	rtems_fdt_node_check_compatible (rtems_fdt_handle handle, int nodeoffset, const char const compatible)

int	rtems_fdt_node_offset_by_compatible (rtems_fdt_handle handle, int startoffset, const char compatible)

int	rtems_fdt_next_node (rtems_fdt_handle handle, int offset, int depth)

const char *	rtems_fdt_strerror (int errval)

bool	rtems_fdt_get_parent_prop_value (rtems_fdt_handle handle, int nodeoffset, const char name, uint32_t *value)

int	rtems_fdt_prop_value (const char const path, const char const propname, void value, size_t size)

int	rtems_fdt_prop_map (const char const path, const char const propname, const char const names[], uintptr_t values, size_t count)

int	rtems_fdt_get_value (const char const path, const char const property, size_t size, uintptr_t *value)

int	rtems_fdt_num_entries (rtems_fdt_handle *handle)

const char *	rtems_fdt_entry_name (rtems_fdt_handle *handle, int id)

int	rtems_fdt_entry_offset (rtems_fdt_handle *handle, int id)

uintptr_t	rtems_fdt_get_offset_len_uintptr (const void *prop, int offset, int len)

uint32_t	rtems_fdt_get_uint32 (const void *prop)

uint32_t	rtems_fdt_get_offset_uint32 (const void *prop, int offset)

uint64_t	rtems_fdt_get_uint64 (const void *prop)

uint64_t	rtems_fdt_get_offset_uint64 (const void *prop, int offset)

uintptr_t	rtems_fdt_get_uintptr (const void *prop)

uintptr_t	rtems_fdt_get_offset_uintptr (const void *prop, int offset)

int	rtems_fdt_getprop_address_cells (rtems_fdt_handle *handle, int nodeoffset)

int	rtems_fdt_getprop_size_cells (rtems_fdt_handle *handle, int nodeoffset)

int	rtems_fdt_getprop_address_map (rtems_fdt_handle handle, const char path, const char name, rtems_fdt_address_map addr_map)

Detailed Description

RTEMS Flattened Device Tree.

Support for loading, managing and accessing FDT blobs in RTEMS.

Macro Definition Documentation

◆ RTEMS_FDT_ERR_BADLAYOUT

#define RTEMS_FDT_ERR_BADLAYOUT 12

RTEMS_FDT_ERR_BADLAYOUT: For read-write functions, the given device tree has it's sub-blocks in an order that the function can't handle (memory reserve map, then structure, then strings). Use rtems_fdt_open_into() to reorganize the tree into a form suitable for the read-write operations.

◆ RTEMS_FDT_ERR_BADLENGTH

#define RTEMS_FDT_ERR_BADLENGTH 105

The property length is invalid

◆ RTEMS_FDT_ERR_BADMAGIC

#define RTEMS_FDT_ERR_BADMAGIC 9

RTEMS_FDT_ERR_BADMAGIC: Given "device tree" appears not to be a device tree at all - it is missing the flattened device tree magic number.

◆ RTEMS_FDT_ERR_BADOFFSET

#define RTEMS_FDT_ERR_BADOFFSET 4

RTEMS_FDT_ERR_BADOFFSET: Function was passed a structure block offset which is out-of-bounds, or which points to an unsuitable part of the structure for the operation.

◆ RTEMS_FDT_ERR_BADPATH

#define RTEMS_FDT_ERR_BADPATH 5

RTEMS_FDT_ERR_BADPATH: Function was passed a badly formatted path (e.g. missing a leading / for a function which requires an absolute path)

◆ RTEMS_FDT_ERR_BADPHANDLE

#define RTEMS_FDT_ERR_BADPHANDLE 6

RTEMS_FDT_ERR_BADPHANDLE: Function was passed an invalid phandle value. phandle values of 0 and -1 are not permitted.

◆ RTEMS_FDT_ERR_BADSTATE

#define RTEMS_FDT_ERR_BADSTATE 7

RTEMS_FDT_ERR_BADSTATE: Function was passed an incomplete device tree created by the sequential-write functions, which is not sufficiently complete for the requested operation.

◆ RTEMS_FDT_ERR_BADSTRUCTURE

#define RTEMS_FDT_ERR_BADSTRUCTURE 11

RTEMS_FDT_ERR_BADSTRUCTURE: Given device tree has a corrupt structure block or other serious error (e.g. misnested nodes, or subnodes preceding properties).

◆ RTEMS_FDT_ERR_BADVERSION

#define RTEMS_FDT_ERR_BADVERSION 10

RTEMS_FDT_ERR_BADVERSION: Given device tree has a version which can't be handled by the requested operation. For read-write functions, this may mean that rtems_fdt_open_into() is required to convert the tree to the expected version.

◆ RTEMS_FDT_ERR_EXISTS

#define RTEMS_FDT_ERR_EXISTS 2

RTEMS_FDT_ERR_EXISTS: Attemped to create a node or property which already exists

◆ RTEMS_FDT_ERR_INTERNAL

#define RTEMS_FDT_ERR_INTERNAL 13

"Can't happen" error indicating a bug in libfdt

◆ RTEMS_FDT_ERR_INVALID_HANDLE

#define RTEMS_FDT_ERR_INVALID_HANDLE 100

Invalid handle.

◆ RTEMS_FDT_ERR_NO_MEMORY

#define RTEMS_FDT_ERR_NO_MEMORY 101

No memory.

◆ RTEMS_FDT_ERR_NOSPACE

#define RTEMS_FDT_ERR_NOSPACE 3

RTEMS_FDT_ERR_NOSPACE: Operation needed to expand the device tree, but its buffer did not have sufficient space to contain the expanded tree. Use rtems_fdt_open_into() to move the device tree to a buffer with more space.

◆ RTEMS_FDT_ERR_NOT_FOUND

#define RTEMS_FDT_ERR_NOT_FOUND 102

File not found.

◆ RTEMS_FDT_ERR_NOTFOUND

#define RTEMS_FDT_ERR_NOTFOUND 1

RTEMS_FDT_ERR_NOTFOUND: The requested node or property does not exist

◆ RTEMS_FDT_ERR_READ_FAIL

#define RTEMS_FDT_ERR_READ_FAIL 103

Cannot read the DTB into memory.

◆ RTEMS_FDT_ERR_REFERENCED

#define RTEMS_FDT_ERR_REFERENCED 104

The blob cannot be unloaded as it is referenced.

◆ RTEMS_FDT_ERR_TRUNCATED

#define RTEMS_FDT_ERR_TRUNCATED 8

RTEMS_FDT_ERR_TRUNCATED: Structure block of the given device tree ends without an RTEMS_FDT_END tag.

Function Documentation

◆ rtems_fdt_dup_handle()

void rtems_fdt_dup_handle	(	rtems_fdt_handle *	from,
		rtems_fdt_handle *	to
	)

Duplicate a handle. The copy must be released.

Parameters

from	Duplicate from this handle.
to	Duplicate to this handle.

◆ rtems_fdt_entry_name()

const char * rtems_fdt_entry_name	(	rtems_fdt_handle *	handle,
		int	id
	)

Get the numbered entry name. Note that the id isn't the same as the offset - it's numbered 0, 1, 2 ... num_entries-1

◆ rtems_fdt_entry_offset()

int rtems_fdt_entry_offset	(	rtems_fdt_handle *	handle,
		int	id
	)

Get the numbered entry offset. Note that the id isn't the same as the offset - it's numbered 0, 1, 2 ... num_entries-1

◆ rtems_fdt_find_path_offset()

int rtems_fdt_find_path_offset	(	rtems_fdt_handle *	handle,
		const char *	path
	)

Find a tree node by its full path looking across of loaded blobs.. Each path component may omit the unit address portion, but the results of this are undefined if any such path component is ambiguous (that is if there are multiple nodes at the relevant level matching the given component, differentiated only by unit address).

If the handle points to a valid blob it is release and the search starts from the first blob.

Parameters

handle	The FDT handle assigned to the blob if found else left invalid.
path	Full path of the node to locate.
int	If less than 0 an error code else the node offset is returned.

◆ rtems_fdt_first_prop_offset()

int rtems_fdt_first_prop_offset	(	rtems_fdt_handle *	handle,
		int	nodeoffset
	)

Retrieve the offset for the first property for a node.

Parameters

handle	The FDT handle to the current blob.
nodeoffset	Structure block offset of the starting node.

Returns: int The offset of a node's first property.

◆ rtems_fdt_get_alias()

const char * rtems_fdt_get_alias	(	rtems_fdt_handle *	handle,
		const char *	name
	)

Retreive the path referenced by a given alias. That is, the value of the property named 'name' in the node /aliases.

Parameters

handle	The FDT handle to the current blob.
name	The name of the alias to look up.

Returns: const char* A pointer to the expansion of the alias named 'name', of it exists NULL, if the given alias or the /aliases node does not exist

◆ rtems_fdt_get_alias_namelen()

const char * rtems_fdt_get_alias_namelen	(	rtems_fdt_handle *	handle,
		const char *const	name,
		int	namelen
	)

Get alias based on substring. Identical to rtems_fdt_get_alias(), but only examine the first namelen characters of name for matching the alias name.

Parameters

handle	The FDT handle to the current blob.
name	The name of the alias th look up.
namelen	The number of characters of name to consider.

Returns: const char* The alias or NULL.

◆ rtems_fdt_get_mem_rsv()

int rtems_fdt_get_mem_rsv	(	rtems_fdt_handle *	handle,
		int	n,
		uint64_t *	address,
		uint64_t *	size
	)

Retrieve one memory reserve map entry. On success, *address and *size will contain the address and size of the n-th reserve map entry from the device tree blob, in native-endian format.

Parameters

blob_desc	A valid blob descriptor.
address	Pointer to 64-bit variables to hold the addresses.
size	Pointer to 64-bit variables to hold the size.

Returns: int If less than 0 it is an error code else 0 is returned on success.

◆ rtems_fdt_get_name()

const char * rtems_fdt_get_name	(	rtems_fdt_handle *	handle,
		int	nodeoffset,
		int *	length
	)

Retrieve the name of a given node (including unit address) of the device tree node at structure block offset @nodeoffset. If @length is non-NULL, the length of this name is also returned, in the integer pointed to by @length.

Parameters

handle	The FDT handle to the current blob.
nodeoffset	Structure block offset of the starting node.
length	Pointer to an integer variable or NULL. If non-NULL, this will be overwritten with either the length in bytes or the error code.

Returns: const char* The node's name on success or NULL on error. The length if non-NULL will hold the error code.

◆ rtems_fdt_get_parent_prop_value()

bool rtems_fdt_get_parent_prop_value	(	rtems_fdt_handle *	handle,
		int	nodeoffset,
		const char *	name,
		uint32_t *	value
	)

Return a parent property given a node offset. Travel up until found or the root node is reached

◆ rtems_fdt_get_path()

int rtems_fdt_get_path	(	rtems_fdt_handle *	handle,
		int	nodeoffset,
		char *	buf,
		int	buflen
	)

Determine the full path of a node. This function is expensive, as it must scan the device tree structure from the start to nodeoffset. It computes the full path of the node at offset nodeoffset, and records that path in the buffer at buf.

Parameters

handle	The FDT handle to the current blob.
nodeoffset	The offset of the node whose path to find.
buf	A character buffer to contain the returned path (will be overwritten)
buflen	The size of the character buffer at buf.

Returns: int 0 on success of an error code.

◆ rtems_fdt_get_phandle()

uint32_t rtems_fdt_get_phandle	(	rtems_fdt_handle *	handle,
		int	nodeoffset
	)

Retrieve the phandle of the device tree node at structure block offset nodeoffset.

Parameters

handle The FDT handle to the current blob. @oaram nodeoffset The structure block offset of the node. return uint32_t The phandle of the node at nodeoffset, on success (!= 0, != -1) 0, if the node has no phandle, or another error occurs.

◆ rtems_fdt_getprop()

const void * rtems_fdt_getprop	(	rtems_fdt_handle *	handle,
		int	nodeoffset,
		const char *const	name,
		int *	length
	)

Retrieve the value of a given property. Retrieves a pointer to the value of the property named 'name' of the node at offset nodeoffset (this will be a pointer to within the device blob itself, not a copy of the value). If lenp is non-NULL, the length of the property value is also returned, in the integer pointed to by @length.

Parameters

handle	The FDT handle to the current blob.
nodeoffset	The offset of the node whose property to find.
name	The name of the property to find.
length	Pointer to an integer variable or NULL. If non-NULL, this will be overwritten with either the length in bytes or the error code.

Returns: const void* The node's property on success or NULL on error. The length if non-NULL will hold the error code.

◆ rtems_fdt_getprop_by_offset()

const void * rtems_fdt_getprop_by_offset	(	rtems_fdt_handle *	handle,
		int	propoffset,
		const char **	name,
		int *	length
	)

Retrieve the property value, name and length of name given a property offset.

Parameters

handle	The FDT handle to the current blob.
propoffset	Property offset
name	If not NULL set the pointer to the name string.
length	Pointer to an integer variable or NULL. If non-NULL, this will be overwritten with either the length in bytes or the error code.

Returns: const void* The node's value data.

◆ rtems_fdt_getprop_namelen()

const void * rtems_fdt_getprop_namelen	(	rtems_fdt_handle *	handle,
		int	nodeoffset,
		const char *const	name,
		int	namelen,
		int *	length
	)

Get property value based on substring. Identical to rtems_fdt_getprop(), but only examine the first namelen characters of name for matching the property name.

Parameters

handle	The FDT handle to the current blob.
nodeoffset	Offset of the node whose property to find
name	The name of the property to find
namelen	The number of characters of name to consider
length	Pointer to an integer variable or NULL. If non-NULL, this will be overwritten with either the length in bytes or the error code.

Returns: const void* The node's property on success or NULL on error. The length if non-NULL will hold the error code.

◆ rtems_fdt_init_handle()

void rtems_fdt_init_handle ( rtems_fdt_handle * handle )

Initialise a handle to a default state.

Parameters

handle The handle to initialise.

◆ rtems_fdt_load()

int rtems_fdt_load	(	const char *const	filename,
		rtems_fdt_handle *	handle
	)

Load a device tree blob or DTB file into memory and register it on the chain of blobs.

Parameters

filename	The name of the blob file to load.
handle	The handle returns the reference to the blob once load.

Returns: int If less than 0 it is an error code else it is the blob descriptor.

◆ rtems_fdt_next_node()

int rtems_fdt_next_node	(	rtems_fdt_handle *	handle,
		int	offset,
		int *	depth
	)

Traverse to the next node.

Parameters

handle	The FDT handle to the current blob.
offset	The offset in the blob to start looking for the next node.
depth	Pointer to return the depth the node is.

Returns: int If less than 0 an error else the node offset.

◆ rtems_fdt_next_prop_offset()

int rtems_fdt_next_prop_offset	(	rtems_fdt_handle *	handle,
		int	propoffset
	)

Retrieve the next property of a node relative to the property

Parameters

handle	The FDT handle to the current blob.
propoffset	Property offset to search from

Returns: int Property offset or end if less than 0.

◆ rtems_fdt_node_check_compatible()

int rtems_fdt_node_check_compatible	(	rtems_fdt_handle *	handle,
		int	nodeoffset,
		const char *const	compatible
	)

Check a node's compatible property returning 0 if the given node contains a 'compatible' property with the given string as one of its elements, it returns non-zero otherwise, or on error.

Parameters

handle	The FDT handle to the current blob.
nodeoffset	The offset of a tree node.
compatible	The string to match against.

Return values

0,if	the node has a 'compatible' property listing the given string.
1,if	the node has a 'compatible' property, but it does not list the given string

◆ rtems_fdt_node_depth()

int rtems_fdt_node_depth	(	rtems_fdt_handle *	handle,
		int	nodeoffset
	)

Find the depth of a given node. The root node has depth 0, its immediate subnodes depth 1 and so forth.

Note: This function is expensive, as it must scan the device tree structure from the start to nodeoffset.

Parameters

handle	The FDT handle to the current blob.
nodeoffset	The offset of the node whose parent to find.

Returns: int If less than 0 an error else the node offset.

◆ rtems_fdt_node_offset_by_compatible()

int rtems_fdt_node_offset_by_compatible	(	rtems_fdt_handle *	handle,
		int	startoffset,
		const char *	compatible
	)

Find nodes with a given 'compatible' value returning the offset of the first node after startoffset, which has a 'compatible' property which lists the given compatible string; or if startoffset is -1, the very first such node in the tree.

To iterate through all nodes matching the criterion, the following idiom can be used:

offset = rtems_fdt_node_offset_by_compatible(blob, -1, compatible); while (offset != -RTEMS_FDT_ERR_NOTFOUND) { // other code here offset = rtems_fdt_node_offset_by_compatible(blob, offset, compatible); }

Note: The -1 in the first call to the function, if 0 is used here instead, the function will never locate the root node, even if it matches the criterion.

Parameters

handle	The FDT handle to the current blob.
startoffset	Only find nodes after this offset.
compatible	The 'compatible' string to match against.

Returns: int If less than 0 an error else the node offset.

◆ rtems_fdt_node_offset_by_phandle()

int rtems_fdt_node_offset_by_phandle	(	rtems_fdt_handle *	handle,
		uint32_t	phandle
	)

Find the node with a given phandle returning the offset of the node which has the given phandle value. If there is more than one node in the tree with the given phandle (an invalid tree), results are undefined.

Parameters

handle	The FDT handle to the current blob.
phandle	The phandle value.

Returns: int If less than 0 an error else the node offset.

◆ rtems_fdt_node_offset_by_prop_value()

int rtems_fdt_node_offset_by_prop_value	(	rtems_fdt_handle *	handle,
		int	startoffset,
		const char *const	propname,
		const void *	propval,
		int	proplen
	)

Find nodes with a given property value. This funtion returns the offset of the first node after startoffset, which has a property named propname whose value is of length proplen and has value equal to propval; or if startoffset is -1, the very first such node in the tree.

To iterate through all nodes matching the criterion, the following idiom can be used: offset = rtemsfdt_node_offset_by_prop_value(blob, -1, propname, propval, proplen); while (offset != -RTEMS_FDT_ERR_NOTFOUND) { // other code here offset = rtems_fdt_node_offset_by_prop_value(fdt, offset, propname, propval, proplen); }

Note: The -1 in the first call to the function, if 0 is used here instead, the function will never locate the root node, even if it matches the criterion.

Parameters

handle	The FDT handle to the current blob.
startoffset	Only find nodes after this offset.
propname	The property name to check.
propval	The property value to search for.
proplen	The length of the value in propval.

Returns: int The structure block offset of the located node (>= 0, >startoffset), on success and an error code is less than 0.

◆ rtems_fdt_num_entries()

int rtems_fdt_num_entries ( rtems_fdt_handle * handle )

Get the number of entries in an FDT handle.

◆ rtems_fdt_num_mem_rsv()

int rtems_fdt_num_mem_rsv ( rtems_fdt_handle * handle )

Returns the number of entries in the device tree blob's memory reservation map. This does not include the terminating 0,0 entry or any other (0,0) entries reserved for expansion.

Parameters

blob_desc A valid blob descriptor.

Returns: int The number of entries.

◆ rtems_fdt_parent_offset()

int rtems_fdt_parent_offset	(	rtems_fdt_handle *	handle,
		int	nodeoffset
	)

Find the parent of a given node. This funciton locates the parent node of a given node (that is, it finds the offset of the node which contains the node at nodeoffset as a subnode).

Note: This function is expensive, as it must scan the device tree structure from the start to nodeoffset, twice.

Parameters

handle	The FDT handle to the current blob.
nodeoffset	The offset of the node whose parent to find.

Returns: int If less than 0 an error else the node offset.

◆ rtems_fdt_path_offset()

int rtems_fdt_path_offset	(	rtems_fdt_handle *	handle,
		const char *	path
	)

Find a tree node by its full path. Each path component may omit the unit address portion, but the results of this are undefined if any such path component is ambiguous (that is if there are multiple nodes at the relevant level matching the given component, differentiated only by unit address).

Parameters

handle	The FDT handle to the current blob.
path	Full path of the node to locate.
int	If less than 0 an error code else the node offset is returned.

◆ rtems_fdt_prop_map()

int rtems_fdt_prop_map	(	const char *const	path,
		const char *const	propname,
		const char *const	names[],
		uintptr_t *	values,
		size_t	count
	)

Create a map given a path the property name and the names of the subnodes of the path.

◆ rtems_fdt_prop_value()

int rtems_fdt_prop_value	(	const char *const	path,
		const char *const	propname,
		void *	value,
		size_t *	size
	)

Return a property given a path.

◆ rtems_fdt_register()

int rtems_fdt_register	(	const void *	blob,
		rtems_fdt_handle *	handle
	)

Register a device tree blob or DTB on to the chain of blobs.

Parameters

blob_desc	A pointer to the blob.
handle	The handle returns the reference to the blob once load.

Returns: int If less than 0 it is an error code else it is the blob descriptor.

◆ rtems_fdt_release_handle()

void rtems_fdt_release_handle ( rtems_fdt_handle * handle )

Release a blob from a handle and clear it.

Parameters

handle The handle to check.

◆ rtems_fdt_strerror()

const char * rtems_fdt_strerror ( int errval )

Return an error string given an error value.

Parameters

errval The error value.

Returns: const char* The error string.

◆ rtems_fdt_subnode_offset()

int rtems_fdt_subnode_offset	(	rtems_fdt_handle *	handle,
		int	parentoffset,
		const char *const	name
	)

Find a subnode of a given node at structure block offset parentoffset with the given name. The name may include a unit address, in which case rtems_fdt_subnode_offset() will find the subnode with that unit address, or the unit address may be omitted, in which case rtems_fdt_subnode_offset() will find an arbitrary subnode whose name excluding unit address matches the given name.

Parameters

blob_desc	A valid blob descriptor.
parentoffset	Structure block offset of a node.
name	The name of the subnode to locate.

Returns: int If less than 0 it is an error code else the subnode offset is returned.

◆ rtems_fdt_subnode_offset_namelen()

int rtems_fdt_subnode_offset_namelen	(	rtems_fdt_handle *	handle,
		int	parentoffset,
		const char *const	name,
		int	namelen
	)

Find a subnode based on substring. Identical to rtems_fdt_subnode_offset(), but only examine the first namelen characters of name for matching the subnode name. This is useful for finding subnodes based on a portion of a larger string, such as a full path.

Parameters

blob_desc	A valid blob descriptor.
parentoffset	Structure block offset of a node
name	Name of the subnode to locate.
namelen	Number of characters of name to consider.

Returns: int If less than 0 it is an error code else the node offset is returned.

◆ rtems_fdt_supernode_atdepth_offset()

int rtems_fdt_supernode_atdepth_offset	(	rtems_fdt_handle *	handle,
		int	nodeoffset,
		int	supernodedepth,
		int *	nodedepth
	)

Find a specific ancestor of a node at a specific depth from the root (where the root itself has depth 0, its immediate subnodes depth 1 and so forth). So rtems_fdt_supernode_atdepth_offset(blob, nodeoffset, 0, NULL); will always return 0, the offset of the root node. If the node at nodeoffset has depth D, then: rtems_fdt_supernode_atdepth_offset(blob, nodeoffset, D, NULL); will return nodeoffset itself.

Parameters

handle	The FDT handle to the current blob.
nodeoffset	The offset of the node whose parent to find.
supernodedepth	The depth of the ancestor to find. @oaram nodedepth The pointer to an integer variable (will be overwritten) or NULL

Returns: int If less than 0 an error else the node offset.

◆ rtems_fdt_unload()

int rtems_fdt_unload ( rtems_fdt_handle * handle )

Unload a device tree blob or DTB file and release any memory allocated when loading. The blob is removed from the list if registered.

Parameters

blob_desc A valid blob descriptor.

Returns: int If less than 0 it is an error code else 0 is return on success.

◆ rtems_fdt_valid_handle()

bool rtems_fdt_valid_handle ( const rtems_fdt_handle * handle )

Check if a handle had a valid blob assigned.

Parameters

handle The handle to check.

Return values

true	The handle has a valid blob.
false	The handle does not have a valid blob.

Data Structures

Macros

Typedefs

Functions

Detailed Description

Macro Definition Documentation

◆ RTEMS_FDT_ERR_BADLAYOUT

◆ RTEMS_FDT_ERR_BADLENGTH

◆ RTEMS_FDT_ERR_BADMAGIC

◆ RTEMS_FDT_ERR_BADOFFSET

◆ RTEMS_FDT_ERR_BADPATH

◆ RTEMS_FDT_ERR_BADPHANDLE

◆ RTEMS_FDT_ERR_BADSTATE

◆ RTEMS_FDT_ERR_BADSTRUCTURE

◆ RTEMS_FDT_ERR_BADVERSION

◆ RTEMS_FDT_ERR_EXISTS

◆ RTEMS_FDT_ERR_INTERNAL

◆ RTEMS_FDT_ERR_INVALID_HANDLE

◆ RTEMS_FDT_ERR_NO_MEMORY

◆ RTEMS_FDT_ERR_NOSPACE

◆ RTEMS_FDT_ERR_NOT_FOUND

◆ RTEMS_FDT_ERR_NOTFOUND

◆ RTEMS_FDT_ERR_READ_FAIL

◆ RTEMS_FDT_ERR_REFERENCED

◆ RTEMS_FDT_ERR_TRUNCATED

Function Documentation

◆ rtems_fdt_dup_handle()

◆ rtems_fdt_entry_name()

◆ rtems_fdt_entry_offset()

◆ rtems_fdt_find_path_offset()

◆ rtems_fdt_first_prop_offset()

◆ rtems_fdt_get_alias()

◆ rtems_fdt_get_alias_namelen()

◆ rtems_fdt_get_mem_rsv()

◆ rtems_fdt_get_name()

◆ rtems_fdt_get_parent_prop_value()

◆ rtems_fdt_get_path()

◆ rtems_fdt_get_phandle()

◆ rtems_fdt_getprop()

◆ rtems_fdt_getprop_by_offset()

◆ rtems_fdt_getprop_namelen()

◆ rtems_fdt_init_handle()

◆ rtems_fdt_load()

◆ rtems_fdt_next_node()

◆ rtems_fdt_next_prop_offset()

◆ rtems_fdt_node_check_compatible()

◆ rtems_fdt_node_depth()

◆ rtems_fdt_node_offset_by_compatible()

◆ rtems_fdt_node_offset_by_phandle()

◆ rtems_fdt_node_offset_by_prop_value()

◆ rtems_fdt_num_entries()

◆ rtems_fdt_num_mem_rsv()

◆ rtems_fdt_parent_offset()

◆ rtems_fdt_path_offset()

◆ rtems_fdt_prop_map()

◆ rtems_fdt_prop_value()

◆ rtems_fdt_register()

◆ rtems_fdt_release_handle()

◆ rtems_fdt_strerror()

◆ rtems_fdt_subnode_offset()

◆ rtems_fdt_subnode_offset_namelen()

◆ rtems_fdt_supernode_atdepth_offset()

◆ rtems_fdt_unload()

◆ rtems_fdt_valid_handle()