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[mirror_edk2.git] / MdePkg / Library / PeiServicesTablePointerLibIdt / PeiServicesTablePointer.c

diff --git a/MdePkg/Library/PeiServicesTablePointerLibIdt/PeiServicesTablePointer.c b/MdePkg/Library/PeiServicesTablePointerLibIdt/PeiServicesTablePointer.c
index 6a52451381bfcaab73723968a2ab5f8428c525be..e38db636e89d139e699afea79b8494a46d9ecbac 100644 (file)
--- a/MdePkg/Library/PeiServicesTablePointerLibIdt/PeiServicesTablePointer.c
+++ b/MdePkg/Library/PeiServicesTablePointerLibIdt/PeiServicesTablePointer.c
@@ -1,6 +1,9 @@
 /** @file\r
   PEI Services Table Pointer Library for IA-32 and X64.\r
 \r
+  According to PI specification, the peiservice pointer is stored prior at IDT\r
+  table in IA32 and x64 architecture.\r
+  \r
   Copyright (c) 2006 - 2007, Intel Corporation.<BR>\r
   All rights reserved. This program and the accompanying materials                          \r
   are licensed and made available under the terms and conditions of the BSD License         \r
@@ -12,7 +15,11 @@
 \r
 **/\r
 \r
-#include "InternalPeiServicesTablePointer.h"\r
+#include <PiPei.h>\r
+\r
+#include <Library/BaseLib.h>\r
+#include <Library/PeiServicesTablePointerLib.h>\r
+#include <Library/DebugLib.h>\r
 \r
 /**\r
   \r
@@ -23,7 +30,8 @@
   base addres is used to save the EFI_PEI_SERVICES**.\r
   For x64, the eight-bytes field immediately prior to new IDT\r
   base addres is used to save the EFI_PEI_SERVICES**\r
-  @retval  The pointer to PeiServices.\r
+  \r
+  @return  The pointer to PeiServices.\r
 \r
 **/\r
 EFI_PEI_SERVICES **\r
@@ -33,9 +41,37 @@ GetPeiServicesTablePointer (
   )\r
 {\r
   EFI_PEI_SERVICES  **PeiServices;\r
-\r
-  PeiServices = (EFI_PEI_SERVICES **) AsmPeiSevicesTablePointer ();\r
+  IA32_DESCRIPTOR   Idtr;\r
+  \r
+  AsmReadIdtr (&Idtr);\r
+  PeiServices = (EFI_PEI_SERVICES **) (*(UINTN*)(Idtr.Base - sizeof (UINTN)));\r
   ASSERT (PeiServices != NULL);\r
   return PeiServices;\r
 }\r
 \r
+/**\r
+  \r
+  The function sets the pointer to PeiServicee following\r
+  PI1.0.\r
+  \r
+  For IA32, the four-bytes field immediately prior to new IDT\r
+  base addres is used to save the EFI_PEI_SERVICES**.\r
+  For x64, the eight-bytes field immediately prior to new IDT\r
+  base addres is used to save the EFI_PEI_SERVICES**\r
+  \r
+  @param PeiServicesTablePointer  The pointer to PeiServices.\r
+\r
+**/\r
+VOID\r
+EFIAPI\r
+SetPeiServicesTablePointer (\r
+  EFI_PEI_SERVICES ** PeiServicesTablePointer\r
+  )\r
+{\r
+  IA32_DESCRIPTOR   Idtr;\r
+  \r
+  AsmReadIdtr (&Idtr);\r
+  (*(UINTN*)(Idtr.Base - sizeof (UINTN))) = (UINTN)PeiServicesTablePointer;\r
+}\r
+\r
+\r