1 files changed, 104 insertions, 0 deletions
diff --git a/MdePkg/Library/SmmServicesTableLib/SmmServicesTableLib.c b/MdePkg/Library/SmmServicesTableLib/SmmServicesTableLib.c
new file mode 100644
index 0000000000..f44dd6ef70
--- /dev/null
+++ b/MdePkg/Library/SmmServicesTableLib/SmmServicesTableLib.c
@@ -0,0 +1,104 @@
+/** @file
+  SMM Services Table Library.
+
+  Copyright (c) 2009, Intel Corporation<BR>
+  All rights reserved. This program and the accompanying materials
+  are licensed and made available under the terms and conditions of the BSD License
+  which accompanies this distribution.  The full text of the license may be found at
+  http://opensource.org/licenses/bsd-license.php
+
+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include <PiDxe.h>
+#include <PiSmm.h>
+#include <Protocol/SmmBase2.h>
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/SmmServicesTableLib.h>
+#include <Library/DebugLib.h>
+
+EFI_SMM_SYSTEM_TABLE2        *gSmst              = NULL;
+EFI_SMM_BASE2_PROTOCOL       *mInternalSmmBase2  = NULL;
+
+
+/**
+  The constructor function caches the pointer of Smm Services Table.
+
+  @param  ImageHandle   The firmware allocated handle for the EFI image.
+  @param  SystemTable   A pointer to the EFI System Table.
+
+  @retval EFI_SUCCESS   The constructor always returns EFI_SUCCESS.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmServicesTableLibConstructor (
+  IN EFI_HANDLE        ImageHandle,
+  IN EFI_SYSTEM_TABLE  *SystemTable
+  )
+{
+  EFI_STATUS                   Status;
+  BOOLEAN                      InSmm;
+
+  //
+  // Retrieve SMM Base2 Protocol
+  //
+  Status = gBS->LocateProtocol (
+                  &gEfiSmmBase2ProtocolGuid,
+                  NULL,
+                  (VOID **) &mInternalSmmBase2
+                  );
+  ASSERT_EFI_ERROR (Status);
+  ASSERT (mInternalSmmBase2 != NULL);
+
+  //
+  // Check to see if we are already in SMM
+  //
+  mInternalSmmBase2->InSmm (mInternalSmmBase2, &InSmm);
+
+  if (!InSmm) {
+    //
+    // We are not in SMM, so SMST is not needed
+    //
+    return EFI_SUCCESS;
+  }
+
+  //
+  // We are in SMM, retrieve the pointer to SMM System Table
+  //
+  mInternalSmmBase2->GetSmstLocation (mInternalSmmBase2, &gSmst);
+
+  ASSERT (gSmst != NULL);
+
+  return EFI_SUCCESS;
+}
+
+
+/**
+  This function allows the caller to determine if the driver is executing in 
+  System Management Mode(SMM).
+
+  This function returns TRUE if the driver is executing in SMM and FALSE if the 
+  driver is not executing in SMM.
+
+  @retval  TRUE  The driver is executing in System Management Mode (SMM).
+  @retval  FALSE The driver is not executing in System Management Mode (SMM). 
+
+**/
+BOOLEAN
+EFIAPI
+InSmm (
+  VOID
+  )
+{
+  BOOLEAN                      InSmm;
+
+  //
+  // Check to see if we are already in SMM
+  //
+  mInternalSmmBase2->InSmm (mInternalSmmBase2, &InSmm);
+
+  return InSmm;
+}