Vlv2TbltDevicePkg/SmramSaveInfoHandlerSmm/SmramSaveInfoHandlerSmm.c

   1 /** @file
   2   A helper driver to save information to SMRAM after SMRR is enabled.
   3
   4   This driver is for ECP platforms.
   5
   6   Copyright (c) 2010 - 2015, Intel Corporation. All rights reserved.<BR>
   7
   8   This program and the accompanying materials are licensed and made available under
   9   the terms and conditions of the BSD License that accompanies this distribution.
  10   The full text of the license may be found at
  11   http://opensource.org/licenses/bsd-license.php.
  12
  13   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  14   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  15
  16
  17 **/
  18
  19 #include <PiSmm.h>
  20 #include <Library/DebugLib.h>
  21 #include <Library/UefiDriverEntryPoint.h>
  22 #include <Library/UefiRuntimeServicesTableLib.h>
  23 #include <Library/SmmServicesTableLib.h>
  24 #include <Library/BaseLib.h>
  25 #include <Library/BaseMemoryLib.h>
  26 #include <Library/IoLib.h>
  27 #include <Protocol/SmmSwDispatch.h>
  28 #include <Protocol/SmmReadyToLock.h>
  29 #include <Protocol/SmmControl.h>
  30 #include <Guid/Vlv2DeviceRefCodePkgTokenSpace.h>
  31
  32 #define SMM_FROM_SMBASE_DRIVER        0x55
  33 #define SMM_FROM_CPU_DRIVER_SAVE_INFO 0x81
  34
  35 #define EFI_SMRAM_CPU_NVS_HEADER_GUID \
  36   { \
  37     0x429501d9, 0xe447, 0x40f4, 0x86, 0x7b, 0x75, 0xc9, 0x3a, 0x1d, 0xb5, 0x4e \
  38   }
  39
  40 UINT8    mSmiDataRegister;
  41 BOOLEAN  mLocked = FALSE;
  42 EFI_GUID mSmramCpuNvsHeaderGuid = EFI_SMRAM_CPU_NVS_HEADER_GUID;
  43
  44 /**
  45   Dispatch function for a Software SMI handler.
  46
  47   @param  DispatchHandle        The handle of this dispatch function.
  48   @param  DispatchContext       The pointer to the dispatch function's context.
  49                                 The SwSmiInputValue field is filled in
  50                                 by the software dispatch driver prior to
  51                                 invoking this dispatch function.
  52                                 The dispatch function will only be called
  53                                 for input values for which it is registered.
  54
  55   @return None
  56
  57 **/
  58 VOID
  59 EFIAPI
  60 SmramSaveInfoHandler (
  61   IN  EFI_HANDLE                    DispatchHandle,
  62   IN  EFI_SMM_SW_DISPATCH_CONTEXT   *DispatchContext
  63   )
  64 {
  65   ASSERT (DispatchContext != NULL);
  66   ASSERT (DispatchContext->SwSmiInputValue == SMM_FROM_SMBASE_DRIVER);
  67
  68   if (!mLocked && IoRead8 (mSmiDataRegister) == SMM_FROM_CPU_DRIVER_SAVE_INFO) {
  69       CopyMem (
  70         (VOID *)(UINTN)(PcdGetEx64 (&gEfiVLVTokenSpaceGuid, PcdCpuLockBoxDataAddress)),
  71         (VOID *)(UINTN)(PcdGetEx64 (&gEfiVLVTokenSpaceGuid, PcdCpuSmramCpuDataAddress)),
  72         (UINTN)(PcdGetEx64 (&gEfiVLVTokenSpaceGuid, PcdCpuLockBoxSize))
  73         );
  74   }
  75 }
  76
  77 /**
  78   Smm Ready To Lock event notification handler.
  79
  80   It sets a flag indicating that SMRAM has been locked.
  81
  82   @param[in] Protocol   Points to the protocol's unique identifier.
  83   @param[in] Interface  Points to the interface instance.
  84   @param[in] Handle     The handle on which the interface was installed.
  85
  86   @retval EFI_SUCCESS   Notification handler runs successfully.
  87  **/
  88 EFI_STATUS
  89 EFIAPI
  90 SmmReadyToLockEventNotify (
  91   IN CONST EFI_GUID  *Protocol,
  92   IN VOID            *Interface,
  93   IN EFI_HANDLE      Handle
  94   )
  95 {
  96   mLocked = TRUE;
  97   return EFI_SUCCESS;
  98 }
  99
 100 /**
 101   Entry point function of this driver.
 102
 103   @param[in] ImageHandle  The firmware allocated handle for the EFI image.
 104   @param[in] SystemTable  A pointer to the EFI System Table.
 105
 106   @retval EFI_SUCCESS     The entry point is executed successfully.
 107   @retval other           Some error occurs when executing this entry point.
 108 **/
 109 EFI_STATUS
 110 EFIAPI
 111 SmramSaveInfoHandlerSmmMain (
 112   IN EFI_HANDLE        ImageHandle,
 113   IN EFI_SYSTEM_TABLE  *SystemTable
 114   )
 115 {
 116   EFI_STATUS                    Status;
 117   EFI_SMM_SW_DISPATCH_PROTOCOL  *SmmSwDispatch;
 118   EFI_SMM_SW_DISPATCH_CONTEXT   SmmSwDispatchContext;
 119   EFI_HANDLE                    DispatchHandle;
 120   EFI_SMM_CONTROL_PROTOCOL      *SmmControl;
 121   EFI_SMM_CONTROL_REGISTER      SmmControlRegister;
 122   VOID                          *Registration;
 123
 124   //
 125   // Get SMI data register
 126   //
 127   Status = SystemTable->BootServices->LocateProtocol (
 128                                         &gEfiSmmControlProtocolGuid,
 129                                         NULL,
 130                                         (VOID **)&SmmControl
 131                                         );
 132   ASSERT_EFI_ERROR (Status);
 133   Status = SmmControl->GetRegisterInfo (SmmControl, &SmmControlRegister);
 134   ASSERT_EFI_ERROR (Status);
 135   mSmiDataRegister = SmmControlRegister.SmiDataRegister;
 136
 137   //
 138   // Register software SMI handler
 139   //
 140
 141   Status = SystemTable->BootServices->LocateProtocol (
 142                                         &gEfiSmmSwDispatchProtocolGuid,
 143                                         NULL,
 144                                         (VOID **)&SmmSwDispatch
 145                                         );
 146   ASSERT_EFI_ERROR (Status);
 147
 148   SmmSwDispatchContext.SwSmiInputValue = SMM_FROM_SMBASE_DRIVER;
 149   Status = SmmSwDispatch->Register (
 150                             SmmSwDispatch,
 151                             &SmramSaveInfoHandler,
 152                             &SmmSwDispatchContext,
 153                             &DispatchHandle
 154                             );
 155   ASSERT_EFI_ERROR (Status);
 156
 157   //
 158   // Register SMM Ready To Lock Protocol notification
 159   //
 160   Status = gSmst->SmmRegisterProtocolNotify (
 161                     &gEfiSmmReadyToLockProtocolGuid,
 162                     SmmReadyToLockEventNotify,
 163                     &Registration
 164                     );
 165   ASSERT_EFI_ERROR (Status);
 166
 167   return Status;
 168 }
 169