audk/OvmfPkg/Include/Library/QemuFwCfgLib.h

168 lines
3.4 KiB
C

/** @file
QEMU/KVM Firmware Configuration access
Copyright (c) 2011 - 2013, Intel Corporation. All rights reserved.<BR>
Copyright (C) 2013, Red Hat, Inc.
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#ifndef __FW_CFG_LIB__
#define __FW_CFG_LIB__
#include <IndustryStandard/QemuFwCfg.h>
/**
Returns a boolean indicating if the firmware configuration interface
is available or not.
This function may change fw_cfg state.
@retval TRUE The interface is available
@retval FALSE The interface is not available
**/
BOOLEAN
EFIAPI
QemuFwCfgIsAvailable (
VOID
);
/**
Selects a firmware configuration item for reading.
Following this call, any data read from this item will start from
the beginning of the configuration item's data.
@param[in] QemuFwCfgItem - Firmware Configuration item to read
**/
VOID
EFIAPI
QemuFwCfgSelectItem (
IN FIRMWARE_CONFIG_ITEM QemuFwCfgItem
);
/**
Reads firmware configuration bytes into a buffer
If called multiple times, then the data read will
continue at the offset of the firmware configuration
item where the previous read ended.
@param[in] Size - Size in bytes to read
@param[in] Buffer - Buffer to store data into
**/
VOID
EFIAPI
QemuFwCfgReadBytes (
IN UINTN Size,
IN VOID *Buffer OPTIONAL
);
/**
Writes firmware configuration bytes from a buffer
If called multiple times, then the data written will
continue at the offset of the firmware configuration
item where the previous write ended.
@param[in] Size - Size in bytes to write
@param[in] Buffer - Buffer to read data from
**/
VOID
EFIAPI
QemuFwCfgWriteBytes (
IN UINTN Size,
IN VOID *Buffer
);
/**
Skip bytes in the firmware configuration item.
Increase the offset of the firmware configuration item without transferring
bytes between the item and a caller-provided buffer. Subsequent read, write
or skip operations will commence at the increased offset.
@param[in] Size Number of bytes to skip.
**/
VOID
EFIAPI
QemuFwCfgSkipBytes (
IN UINTN Size
);
/**
Reads a UINT8 firmware configuration value
@return Value of Firmware Configuration item read
**/
UINT8
EFIAPI
QemuFwCfgRead8 (
VOID
);
/**
Reads a UINT16 firmware configuration value
@return Value of Firmware Configuration item read
**/
UINT16
EFIAPI
QemuFwCfgRead16 (
VOID
);
/**
Reads a UINT32 firmware configuration value
@return Value of Firmware Configuration item read
**/
UINT32
EFIAPI
QemuFwCfgRead32 (
VOID
);
/**
Reads a UINT64 firmware configuration value
@return Value of Firmware Configuration item read
**/
UINT64
EFIAPI
QemuFwCfgRead64 (
VOID
);
/**
Find the configuration item corresponding to the firmware configuration file.
@param[in] Name - Name of file to look up.
@param[out] Item - Configuration item corresponding to the file, to be passed
to QemuFwCfgSelectItem ().
@param[out] Size - Number of bytes in the file.
@return RETURN_SUCCESS If file is found.
RETURN_NOT_FOUND If file is not found.
RETURN_UNSUPPORTED If firmware configuration is unavailable.
**/
RETURN_STATUS
EFIAPI
QemuFwCfgFindFile (
IN CONST CHAR8 *Name,
OUT FIRMWARE_CONFIG_ITEM *Item,
OUT UINTN *Size
);
#endif