1 files changed, 131 insertions, 0 deletions
diff --git a/Core/MdePkg/Library/PeiServicesTablePointerLibIdt/PeiServicesTablePointer.c b/Core/MdePkg/Library/PeiServicesTablePointerLibIdt/PeiServicesTablePointer.c
new file mode 100644
index 0000000000..dd0a78d653
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+++ b/Core/MdePkg/Library/PeiServicesTablePointerLibIdt/PeiServicesTablePointer.c
@@ -0,0 +1,131 @@
+/** @file
+  PEI Services Table Pointer Library for IA-32 and x64.
+
+  According to PI specification, the peiservice pointer is stored prior at IDT
+  table in IA32 and x64 architecture.
+  
+  Copyright (c) 2006 - 2014, Intel Corporation. All rights reserved.<BR>
+  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 <PiPei.h>
+
+#include <Library/BaseLib.h>
+#include <Library/PeiServicesTablePointerLib.h>
+#include <Library/DebugLib.h>
+#include <Library/BaseMemoryLib.h>
+
+/**
+  Retrieves the cached value of the PEI Services Table pointer.
+
+  Returns the cached value of the PEI Services Table pointer in a CPU specific manner 
+  as specified in the CPU binding section of the Platform Initialization Pre-EFI 
+  Initialization Core Interface Specification.
+  
+  If the cached PEI Services Table pointer is NULL, then ASSERT().
+
+  @return  The pointer to PeiServices.
+
+**/
+CONST EFI_PEI_SERVICES **
+EFIAPI
+GetPeiServicesTablePointer (
+  VOID
+  )
+{
+  CONST EFI_PEI_SERVICES  **PeiServices;
+  IA32_DESCRIPTOR   Idtr;
+  
+  AsmReadIdtr (&Idtr);
+  PeiServices = (CONST EFI_PEI_SERVICES **) (*(UINTN*)(Idtr.Base - sizeof (UINTN)));
+  ASSERT (PeiServices != NULL);
+  return PeiServices;
+}
+
+/**
+  Caches a pointer PEI Services Table. 
+ 
+  Caches the pointer to the PEI Services Table specified by PeiServicesTablePointer 
+  in a CPU specific manner as specified in the CPU binding section of the Platform Initialization 
+  Pre-EFI Initialization Core Interface Specification. 
+  The function set the pointer of PEI services immediately preceding the IDT table
+  according to PI specification.
+  
+  If PeiServicesTablePointer is NULL, then ASSERT().
+  
+  @param    PeiServicesTablePointer   The address of PeiServices pointer.
+**/
+VOID
+EFIAPI
+SetPeiServicesTablePointer (
+  IN CONST EFI_PEI_SERVICES ** PeiServicesTablePointer
+  )
+{
+  IA32_DESCRIPTOR        Idtr;
+  
+  ASSERT (PeiServicesTablePointer != NULL);
+  AsmReadIdtr (&Idtr);
+  (*(UINTN*)(Idtr.Base - sizeof (UINTN))) = (UINTN)PeiServicesTablePointer;
+}
+
+/**
+  Perform CPU specific actions required to migrate the PEI Services Table 
+  pointer from temporary RAM to permanent RAM.
+
+  For IA32 CPUs, the PEI Services Table pointer is stored in the 4 bytes 
+  immediately preceding the Interrupt Descriptor Table (IDT) in memory.
+  For X64 CPUs, the PEI Services Table pointer is stored in the 8 bytes 
+  immediately preceding the Interrupt Descriptor Table (IDT) in memory.
+  For Itanium and ARM CPUs, a the PEI Services Table Pointer is stored in
+  a dedicated CPU register.  This means that there is no memory storage 
+  associated with storing the PEI Services Table pointer, so no additional 
+  migration actions are required for Itanium or ARM CPUs.
+
+  If The cached PEI Services Table pointer is NULL, then ASSERT().
+  If the permanent memory is allocated failed, then ASSERT().
+**/
+VOID
+EFIAPI
+MigratePeiServicesTablePointer (
+  VOID
+  )
+{
+  EFI_STATUS             Status;
+  IA32_DESCRIPTOR        Idtr;
+  EFI_PHYSICAL_ADDRESS   IdtBase;
+  CONST EFI_PEI_SERVICES  **PeiServices;
+
+  //
+  // Get PEI Services Table pointer
+  //
+  AsmReadIdtr (&Idtr);
+  PeiServices = (CONST EFI_PEI_SERVICES **) (*(UINTN*)(Idtr.Base - sizeof (UINTN)));
+  ASSERT (PeiServices != NULL);
+  //
+  // Allocate the permanent memory.
+  //
+  Status = (*PeiServices)->AllocatePages (
+                            PeiServices, 
+                            EfiBootServicesCode,
+                            EFI_SIZE_TO_PAGES(Idtr.Limit + 1 + sizeof (UINTN)),
+                            &IdtBase
+                            );
+  ASSERT_EFI_ERROR (Status);
+  //
+  // Idt table needs to be migrated into memory.
+  //
+  CopyMem ((VOID *) (UINTN) IdtBase, (VOID *) (Idtr.Base - sizeof (UINTN)), Idtr.Limit + 1 + sizeof (UINTN));
+  Idtr.Base = (UINTN) IdtBase + sizeof (UINTN);
+  AsmWriteIdtr (&Idtr);
+  
+  return;
+}
+
+