audk/IntelFrameworkModulePkg/Universal/LegacyRegionDxe/LegacyRegion.c

165 lines
4.7 KiB
C

/** @file
Produces the Legacy Region Protocol.
This generic implementation of the Legacy Region Protocol does not actually
perform any lock/unlock operations. This module may be used on platforms
that do not provide HW locking of the legacy memory regions. It can also
be used as a template driver for implementing the Legacy Region Protocol on
a platform that does support HW locking of the legacy memory regions.
Copyright (c) 2009 - 2018, Intel Corporation. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#include <PiDxe.h>
#include <Protocol/LegacyRegion.h>
#include <Library/DebugLib.h>
#include <Library/UefiBootServicesTableLib.h>
/**
Sets hardware to decode or not decode a region.
@param This Indicates the EFI_LEGACY_REGION_PROTOCOL instance
@param Start Start of region to decode.
@param Length Size in bytes of the region.
@param On Decode/nondecode flag.
@retval EFI_SUCCESS Decode range successfully changed.
**/
EFI_STATUS
EFIAPI
LegacyRegionDecode (
IN EFI_LEGACY_REGION_PROTOCOL *This,
IN UINT32 Start,
IN UINT32 Length,
IN BOOLEAN *On
)
{
return EFI_SUCCESS;
}
/**
Sets a region to read only.
@param This Indicates the EFI_LEGACY_REGION_PROTOCOL instance
@param Start Start of region to lock.
@param Length Size in bytes of the region.
@param Granularity Lock attribute affects this granularity in bytes.
@retval EFI_SUCCESS The region was made read only.
**/
EFI_STATUS
EFIAPI
LegacyRegionLock (
IN EFI_LEGACY_REGION_PROTOCOL *This,
IN UINT32 Start,
IN UINT32 Length,
OUT UINT32 *Granularity OPTIONAL
)
{
return EFI_SUCCESS;
}
/**
Sets a region to read only and ensures that flash is locked from being
inadvertently modified.
@param This Indicates the EFI_LEGACY_REGION_PROTOCOL instance
@param Start Start of region to lock.
@param Length Size in bytes of the region.
@param Granularity Lock attribute affects this granularity in bytes.
@retval EFI_SUCCESS The region was made read only and flash is locked.
**/
EFI_STATUS
EFIAPI
LegacyRegionBootLock (
IN EFI_LEGACY_REGION_PROTOCOL *This,
IN UINT32 Start,
IN UINT32 Length,
OUT UINT32 *Granularity OPTIONAL
)
{
return EFI_SUCCESS;
}
/**
Sets a region to read-write.
@param This Indicates the EFI_LEGACY_REGION_PROTOCOL instance
@param Start Start of region to lock.
@param Length Size in bytes of the region.
@param Granularity Lock attribute affects this granularity in bytes.
@retval EFI_SUCCESS The region was successfully made read-write.
**/
EFI_STATUS
EFIAPI
LegacyRegionUnlock (
IN EFI_LEGACY_REGION_PROTOCOL *This,
IN UINT32 Start,
IN UINT32 Length,
OUT UINT32 *Granularity OPTIONAL
)
{
return EFI_SUCCESS;
}
//
// Module global for the handle the Legacy Region Protocol is installed
//
EFI_HANDLE mLegacyRegionHandle = NULL;
//
// Module global for the Legacy Region Protocol instance that is installed onto
// mLegacyRegionHandle
//
EFI_LEGACY_REGION_PROTOCOL mLegacyRegion = {
LegacyRegionDecode,
LegacyRegionLock,
LegacyRegionBootLock,
LegacyRegionUnlock
};
/**
The user Entry Point for module LegacyRegionDxe. The user code starts with this function.
@param[in] ImageHandle The firmware allocated handle for the EFI image.
@param[in] SystemTable A pointer to the EFI System Table.
@retval EFI_SUCCESS The entry point is executed successfully.
@retval other Some error occurs when executing this entry point.
**/
EFI_STATUS
EFIAPI
LegacyRegionInstall (
IN EFI_HANDLE ImageHandle,
IN EFI_SYSTEM_TABLE *SystemTable
)
{
EFI_STATUS Status;
//
// Make sure the Legacy Region Protocol is not already installed in the system
//
ASSERT_PROTOCOL_ALREADY_INSTALLED (NULL, &gEfiLegacyRegionProtocolGuid);
//
// Install the protocol on a new handle.
//
Status = gBS->InstallMultipleProtocolInterfaces (
&mLegacyRegionHandle,
&gEfiLegacyRegionProtocolGuid, &mLegacyRegion,
NULL
);
ASSERT_EFI_ERROR (Status);
return Status;
}