audk/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLibInternal.h

64 lines
1.7 KiB
C

/** @file
Internal interfaces specific to the QemuFwCfgLib instances in OvmfPkg.
Copyright (C) 2016, Red Hat, Inc.
Copyright (C) 2017, Advanced Micro Devices. All rights reserved
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#ifndef __QEMU_FW_CFG_LIB_INTERNAL_H__
#define __QEMU_FW_CFG_LIB_INTERNAL_H__
/**
Returns a boolean indicating if the firmware configuration interface is
available for library-internal purposes.
This function never changes fw_cfg state.
@retval TRUE The interface is available internally.
@retval FALSE The interface is not available internally.
**/
BOOLEAN
InternalQemuFwCfgIsAvailable (
VOID
);
/**
Returns a boolean indicating whether QEMU provides the DMA-like access method
for fw_cfg.
@retval TRUE The DMA-like access method is available.
@retval FALSE The DMA-like access method is unavailable.
**/
BOOLEAN
InternalQemuFwCfgDmaIsAvailable (
VOID
);
/**
Transfer an array of bytes, or skip a number of bytes, using the DMA
interface.
@param[in] Size Size in bytes to transfer or skip.
@param[in,out] Buffer Buffer to read data into or write data from. Ignored,
and may be NULL, if Size is zero, or Control is
FW_CFG_DMA_CTL_SKIP.
@param[in] Control One of the following:
FW_CFG_DMA_CTL_WRITE - write to fw_cfg from Buffer.
FW_CFG_DMA_CTL_READ - read from fw_cfg into Buffer.
FW_CFG_DMA_CTL_SKIP - skip bytes in fw_cfg.
**/
VOID
InternalQemuFwCfgDmaBytes (
IN UINT32 Size,
IN OUT VOID *Buffer OPTIONAL,
IN UINT32 Control
);
#endif