audk/MdePkg/Include/Library/FdtLib.h

436 lines
10 KiB
C

/** @file
Flattened Device Tree Library.
All structure data are in big-endian format.
Functions are provided for converting data between
little-endian and big-endian.
For example:
Pushing data to FDT blob needs to convert data to
big-endian by CpuToFdt*().
Retrieving data from FDT blob needs to convert data to
little-endian by Fdt*ToCpu().
Refer to FDT specification: https://www.devicetree.org/specifications/
Copyright (c) 2023, Intel Corporation. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#ifndef FDT_LIB_H_
#define FDT_LIB_H_
/**
Flattened Device Tree definition
The Devicetree Blob (DTB) format is a binary encoding with big-endian.
When producing or consuming the blob data, CpuToFdt*() or Fdt*ToCpu()
provided by this library may be called to convert data between
big-endian and little-endian.
**/
typedef struct {
UINT32 Magic; /* magic word FDT_MAGIC */
UINT32 TotalSize; /* total size of DT block */
UINT32 OffsetDtStruct; /* offset to structure */
UINT32 OffsetDtStrings; /* offset to strings */
UINT32 OffsetMemRsvmap; /* offset to memory reserve map */
UINT32 Version; /* format version */
UINT32 LastCompVersion; /* last compatible version */
/* version 2 fields below */
UINT32 BootCpuidPhys; /* Which physical CPU id we're
booting on */
/* version 3 fields below */
UINT32 SizeDtStrings; /* size of the strings block */
/* version 17 fields below */
UINT32 SizeDtStruct; /* size of the structure block */
} FDT_HEADER;
typedef struct {
UINT64 Address;
UINT64 Size;
} FDT_RESERVE_ENTRY;
typedef struct {
UINT32 Tag;
CHAR8 Name[];
} FDT_NODE_HEADER;
typedef struct {
UINT32 Tag;
UINT32 Length;
UINT32 NameOffset;
CHAR8 Data[];
} FDT_PROPERTY;
/**
Convert UINT16 data of the FDT blob to little-endian
@param[in] Value The value to the blob data.
@return The value to be converted to little-endian.
**/
UINT16
EFIAPI
Fdt16ToCpu (
IN UINT16 Value
);
/**
Convert UINT16 data to big-endian for aligned with the FDT blob
@param[in] Value The value to align with the FDT blob.
@return The value to be converted to big-endian.
**/
UINT16
EFIAPI
CpuToFdt16 (
IN UINT16 Value
);
/**
Convert UINT32 data of the FDT blob to little-endian
@param[in] Value The value to the blob data.
@return The value to be converted to little-endian.
**/
UINT32
EFIAPI
Fdt32ToCpu (
IN UINT32 Value
);
/**
Convert UINT32 data to big-endian for aligned with the FDT blob
@param[in] Value The value to align with the FDT blob.
@return The value to be converted to big-endian.
**/
UINT32
EFIAPI
CpuToFdt32 (
IN UINT32 Value
);
/**
Convert UINT64 data of the FDT blob to little-endian
@param[in] Value The value to the blob data.
@return The value to be converted to little-endian.
**/
UINT64
EFIAPI
Fdt64ToCpu (
IN UINT64 Value
);
/**
Convert UINT64 data to big-endian for aligned with the FDT blob
@param[in] Value The value to align with the FDT blob.
@return The value to be converted to big-endian.
**/
UINT64
EFIAPI
CpuToFdt64 (
IN UINT64 Value
);
/**
Verify the header of the Flattened Device Tree
@param[in] Fdt The pointer to FDT blob.
@return Zero for successfully, otherwise failed.
**/
INT32
EFIAPI
FdtCheckHeader (
IN CONST VOID *Fdt
);
/**
Create a empty Flattened Device Tree.
@param[in] Buffer The pointer to allocate a pool for FDT blob.
@param[in] BufferSize The BufferSize to the pool size.
@return Zero for successfully, otherwise failed.
**/
INT32
EFIAPI
FdtCreateEmptyTree (
IN VOID *Buffer,
IN UINT32 BufferSize
);
/**
Returns a offset of next node from the given node.
@param[in] Fdt The pointer to FDT blob.
@param[in] Offset The offset to previous node.
@param[in] Depth The depth to the level of tree hierarchy.
@return The offset to next node offset.
**/
INT32
EFIAPI
FdtNextNode (
IN CONST VOID *Fdt,
IN INT32 Offset,
IN INT32 *Depth
);
/**
Returns a offset of first node under the given node.
@param[in] Fdt The pointer to FDT blob.
@param[in] Offset The offset to previous node.
@return The offset to next node offset.
**/
INT32
EFIAPI
FdtFirstSubnode (
IN CONST VOID *Fdt,
IN INT32 Offset
);
/**
Returns a offset of next node from the given node.
@param[in] Fdt The pointer to FDT blob.
@param[in] Offset The offset to previous node.
@return The offset to next node offset.
**/
INT32
EFIAPI
FdtNextSubnode (
IN CONST VOID *Fdt,
IN INT32 Offset
);
/**
Returns a offset of first node which includes the given name.
@param[in] Fdt The pointer to FDT blob.
@param[in] ParentOffset The offset to the node which start find under.
@param[in] Name The name to search the node with the name.
@param[in] NameLength The length of the name to check only.
@return The offset to node offset with given node name.
**/
INT32
EFIAPI
FdtSubnodeOffsetNameLen (
IN CONST VOID *Fdt,
IN INT32 ParentOffset,
IN CONST CHAR8 *Name,
IN INT32 NameLength
);
/**
Returns a offset of first node which includes the given property name and value.
@param[in] Fdt The pointer to FDT blob.
@param[in] StartOffset The offset to the starting node to find.
@param[in] PropertyName The property name to search the node including the named property.
@param[in] PropertyValue The property value (big-endian) to check the same property value.
@param[in] PropertyLength The length of the value in PropertValue.
@return The offset to node offset with given property.
**/
INT32
EFIAPI
FdtNodeOffsetByPropValue (
IN CONST VOID *Fdt,
IN INT32 StartOffset,
IN CONST CHAR8 *PropertyName,
IN CONST VOID *PropertyValue,
IN INT32 PropertyLength
);
/**
Returns a property with the given name from the given node.
@param[in] Fdt The pointer to FDT blob.
@param[in] NodeOffset The offset to the given node.
@param[in] Name The name to the property which need be searched
@param[in] Length The length to the size of the property found.
@return The property to the structure of the found property. Since the data
come from FDT blob, it's encoding with big-endian.
**/
CONST FDT_PROPERTY *
EFIAPI
FdtGetProperty (
IN CONST VOID *Fdt,
IN INT32 NodeOffset,
IN CONST CHAR8 *Name,
IN INT32 *Length
);
/**
Returns a offset of first property in the given node.
@param[in] Fdt The pointer to FDT blob.
@param[in] NodeOffset The offset to the node which need be searched.
@return The offset to first property offset in the given node.
**/
INT32
EFIAPI
FdtFirstPropertyOffset (
IN CONST VOID *Fdt,
IN INT32 NodeOffset
);
/**
Returns a offset of next property from the given property.
@param[in] Fdt The pointer to FDT blob.
@param[in] Offset The offset to previous property.
@return The offset to next property offset.
**/
INT32
EFIAPI
FdtNextPropertyOffset (
IN CONST VOID *Fdt,
IN INT32 Offset
);
/**
Returns a property from the given offset of the property.
@param[in] Fdt The pointer to FDT blob.
@param[in] Offset The offset to the given offset of the property.
@param[in] Length The length to the size of the property found.
@return The property to the structure of the given property offset.
**/
CONST FDT_PROPERTY *
EFIAPI
FdtGetPropertyByOffset (
IN CONST VOID *Fdt,
IN INT32 Offset,
IN INT32 *Length
);
/**
Returns a string by the given string offset.
@param[in] Fdt The pointer to FDT blob.
@param[in] StrOffset The offset to the location in the strings block of FDT.
@param[in] Length The length to the size of string which need be retrieved.
@return The string to the given string offset.
**/
CONST CHAR8 *
EFIAPI
FdtGetString (
IN CONST VOID *Fdt,
IN INT32 StrOffset,
IN INT32 *Length OPTIONAL
);
/**
Add a new node to the FDT.
@param[in] Fdt The pointer to FDT blob.
@param[in] ParentOffset The offset to the node offset which want to add in.
@param[in] Name The name to name the node.
@return The offset to the new node.
**/
INT32
EFIAPI
FdtAddSubnode (
IN VOID *Fdt,
IN INT32 ParentOffset,
IN CONST CHAR8 *Name
);
/**
Add or modify a property in the given node.
@param[in] Fdt The pointer to FDT blob.
@param[in] NodeOffset The offset to the node offset which want to add in.
@param[in] Name The name to name the property.
@param[in] Value The value (big-endian) to the property value.
@param[in] Length The length to the size of the property.
@return Zero for successfully, otherwise failed.
**/
INT32
EFIAPI
FdtSetProp (
IN VOID *Fdt,
IN INT32 NodeOffset,
IN CONST CHAR8 *Name,
IN CONST VOID *Value,
IN UINT32 Length
);
/**
Returns the name of a given node.
@param[in] Fdt The pointer to FDT blob.
@param[in] NodeOffse Offset of node to check.
@param[in] Length The pointer to an integer variable (will be overwritten) or NULL.
@return The pointer to the node's name.
**/
CONST CHAR8 *
EFIAPI
FdtGetName (
IN VOID *Fdt,
IN INT32 NodeOffset,
IN INT32 *Length
);
/**
FdtNodeDepth() finds the depth of a given node. The root node
has depth 0, its immediate subnodes depth 1 and so forth.
@param[in] Fdt The pointer to FDT blob.
@param[in] NodeOffset Offset of node to check.
@return Depth of the node at NodeOffset.
**/
INT32
EFIAPI
FdtNodeDepth (
IN CONST VOID *Fdt,
IN INT32 NodeOffset
);
#endif /* FDT_LIB_H_ */