alder_lake_bios/Intel/AlderLake/AlderLakePlatSamplePkg/Library/PeiWdtAppLib/PeiWdtAppLib.c

98 lines
3.7 KiB
C

/** @file
Platform-specific Wdt code. Offers more convenient and foolproof API
for manipulating WDT than low-level WDT driver which is part of Reference
Code. WdtApp is too platform-specific to be included in reference code.
However, it is expected that each client will need to write something
similar on his own.
This implementation simply kicks Wdt once before MRC execution starts,
with such timeout value that allows BIOS to arrive in DXE phase where
the Dxe part of this driver takes control of Wdt. There are other
possibilities. For example, a more robust way would be to kick WDT more
often, after each PEI module is loaded, and use shorter timeout values.
@copyright
INTEL CONFIDENTIAL
Copyright 2009 - 2016 Intel Corporation.
The source code contained or described herein and all documents related to the
source code ("Material") are owned by Intel Corporation or its suppliers or
licensors. Title to the Material remains with Intel Corporation or its suppliers
and licensors. The Material may contain trade secrets and proprietary and
confidential information of Intel Corporation and its suppliers and licensors,
and is protected by worldwide copyright and trade secret laws and treaty
provisions. No part of the Material may be used, copied, reproduced, modified,
published, uploaded, posted, transmitted, distributed, or disclosed in any way
without Intel's prior express written permission.
No license under any patent, copyright, trade secret or other intellectual
property right is granted to or conferred upon you by disclosure or delivery
of the Materials, either expressly, by implication, inducement, estoppel or
otherwise. Any license under such intellectual property rights must be
express and approved by Intel in writing.
Unless otherwise agreed by Intel in writing, you may not remove or alter
this notice or any other notice embedded in Materials by Intel or
Intel's suppliers or licensors in any way.
This file contains a 'Sample Driver' and is licensed as such under the terms
of your license agreement with Intel or your vendor. This file may be modified
by the user, subject to the additional terms of the license agreement.
@par Specification Reference:
**/
#include <Library/PeiWdtAppLib.h>
/**
Turns on WDT during PEI phase according to requests made by
OS overclocking application (through WDT status) and BIOS modules (through flash variable)
@param[in] WdtPei
@retval EFI_SUCCESS
**/
EFI_STATUS
PeiWdtApp (
IN WDT_PPI *WdtPei
)
{
EFI_STATUS Status;
EFI_GUID EfiPeiReadOnlyVariable2PpiGuid = EFI_PEI_READ_ONLY_VARIABLE2_PPI_GUID;
WDT_PERSISTENT_DATA WdtStateData;
EFI_PEI_READ_ONLY_VARIABLE2_PPI *ReadOnlyVariable;
UINTN VariableSize;
DEBUG ((DEBUG_INFO, "(WdtApp) PeiWdtApp\n"));
Status = PeiServicesLocatePpi (
&EfiPeiReadOnlyVariable2PpiGuid,
0,
NULL,
(VOID **) &ReadOnlyVariable
);
ASSERT_EFI_ERROR (Status);
VariableSize = sizeof (WdtStateData);
Status = ReadOnlyVariable->GetVariable (
ReadOnlyVariable,
WDT_PERSISTENT_DATA_C_NAME,
&gWdtPersistentDataGuid,
NULL,
&VariableSize,
&WdtStateData
);
if (EFI_ERROR (Status)) {
WdtStateData.Enable = 0;
}
if ((WdtPei->IsWdtRequired() == TRUE) || (WdtPei->IsWdtEnabled() == TRUE) || (WdtStateData.Enable == 1)) {
WdtPei->ReloadAndStart (PcdGet8 (PcdWdtTimeoutBetweenPeiDxe));
} else {
WdtPei->Disable ();
}
return EFI_SUCCESS;
}