IntelFspWrapperPkg: Replace BSD License with BSD+Patent License

[mirror_edk2.git] / IntelFspWrapperPkg / Library / BaseFspApiLib / X64 / DispatchExecute.c

/** @file\r
  Execute 32-bit code in Long Mode.\r
  Provide a thunk function to transition from long mode to compatibility mode to execute 32-bit code and then transit\r
  back to long mode.\r
\r
  Copyright (c) 2014 - 2015, Intel Corporation. All rights reserved.<BR>\r
  SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
#include <Uefi.h>\r
#include <Library/BaseLib.h>\r
#include <FspApi.h>\r
\r
#pragma pack(1)\r
typedef union {\r
  struct {\r
    UINT32  LimitLow    : 16;\r
    UINT32  BaseLow     : 16;\r
    UINT32  BaseMid     : 8;\r
    UINT32  Type        : 4;\r
    UINT32  System      : 1;\r
    UINT32  Dpl         : 2;\r
    UINT32  Present     : 1;\r
    UINT32  LimitHigh   : 4;\r
    UINT32  Software    : 1;\r
    UINT32  Reserved    : 1;\r
    UINT32  DefaultSize : 1;\r
    UINT32  Granularity : 1;\r
    UINT32  BaseHigh    : 8;\r
  } Bits;\r
  UINT64  Uint64;\r
} IA32_GDT;\r
#pragma pack()\r
\r
GLOBAL_REMOVE_IF_UNREFERENCED IA32_GDT mGdtEntries[] = {\r
  {{0,      0,  0,  0,    0,  0,  0,  0,    0,  0, 0,  0,  0}}, /* 0x0:  reserve */\r
  {{0xFFFF, 0,  0,  0xB,  1,  0,  1,  0xF,  0,  0, 1,  1,  0}}, /* 0x8:  compatibility mode */\r
  {{0xFFFF, 0,  0,  0xB,  1,  0,  1,  0xF,  0,  1, 0,  1,  0}}, /* 0x10: for long mode */\r
  {{0xFFFF, 0,  0,  0x3,  1,  0,  1,  0xF,  0,  0, 1,  1,  0}}, /* 0x18: data */\r
  {{0,      0,  0,  0,    0,  0,  0,  0,    0,  0, 0,  0,  0}}, /* 0x20: reserve */\r
};\r
\r
//\r
// IA32 Gdt register\r
//\r
GLOBAL_REMOVE_IF_UNREFERENCED IA32_DESCRIPTOR mGdt = {\r
  sizeof (mGdtEntries) - 1,\r
  (UINTN) mGdtEntries\r
  };\r
\r
/**\r
  Assembly function to transition from long mode to compatibility mode to execute 32-bit code and then transit back to\r
  long mode.\r
\r
  @param[in] Function     The 32bit code entry to be executed.\r
  @param[in] Param1       The first parameter to pass to 32bit code\r
  @param[in] Param2       The second parameter to pass to 32bit code\r
  @param[in] InternalGdtr The GDT and GDT descriptor used by this library\r
\r
  @return status.\r
**/\r
UINT32\r
AsmExecute32BitCode (\r
  IN UINT64           Function,\r
  IN UINT64           Param1,\r
  IN UINT64           Param2,\r
  IN IA32_DESCRIPTOR  *InternalGdtr\r
  );\r
\r
/**\r
  Wrapper for a thunk  to transition from long mode to compatibility mode to execute 32-bit code and then transit back to\r
  long mode.\r
\r
  @param[in] Function     The 32bit code entry to be executed.\r
  @param[in] Param1       The first parameter to pass to 32bit code.\r
\r
  @return EFI_STATUS.\r
**/\r
EFI_STATUS\r
Execute32BitCode (\r
  IN UINT64      Function,\r
  IN UINT64      Param1\r
  )\r
{\r
  EFI_STATUS       Status;\r
  IA32_DESCRIPTOR  Idtr;\r
\r
  //\r
  // Idtr might be changed inside of FSP. 32bit FSP only knows the <4G address.\r
  // If IDTR.Base is >4G, FSP can not handle. So we need save/restore IDTR here for X64 only.\r
  // Interrupt is already disabled here, so it is safety to update IDTR.\r
  //\r
  AsmReadIdtr (&Idtr);\r
  Status = AsmExecute32BitCode (Function, Param1, 0, &mGdt);\r
  AsmWriteIdtr (&Idtr);\r
\r
  return Status;\r
}\r
\r