/** @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 /** 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; }