text: /** @file
    C based implemention of IA32 interrupt handling only
    requiring a minimal assembly interrupt entry point.
  
    Copyright (c) 2006 - 2015, 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.
  
  **/
  
  #ifndef _CPU_GDT_H_
  #define _CPU_GDT_H_
  
  //
  // Local structure definitions
  //
  
  #pragma pack (1)
  
  //
  // Global Descriptor Entry structures
  //
  
  typedef struct _GDT_ENTRY {
    UINT16 Limit15_0;
    UINT16 Base15_0;
    UINT8  Base23_16;
    UINT8  Type;
    UINT8  Limit19_16_and_flags;
    UINT8  Base31_24;
  } GDT_ENTRY;
  
  typedef
  struct _GDT_ENTRIES {
    GDT_ENTRY Null;
    GDT_ENTRY Linear;
    GDT_ENTRY LinearCode;
    GDT_ENTRY SysData;
    GDT_ENTRY SysCode;
    GDT_ENTRY Spare4;
    GDT_ENTRY LinearData64;
    GDT_ENTRY LinearCode64;
    GDT_ENTRY Spare5;
  } GDT_ENTRIES;
  
  #pragma pack ()
  
  #define NULL_SEL          OFFSET_OF (GDT_ENTRIES, Null)
  #define LINEAR_SEL        OFFSET_OF (GDT_ENTRIES, Linear)
  #define LINEAR_CODE_SEL   OFFSET_OF (GDT_ENTRIES, LinearCode)
  #define SYS_DATA_SEL      OFFSET_OF (GDT_ENTRIES, SysData)
  #define SYS_CODE_SEL      OFFSET_OF (GDT_ENTRIES, SysCode)
  #define SPARE4_SEL        OFFSET_OF (GDT_ENTRIES, Spare4)
  #define LINEAR_DATA64_SEL OFFSET_OF (GDT_ENTRIES, LinearData64)
  #define LINEAR_CODE64_SEL OFFSET_OF (GDT_ENTRIES, LinearCode64)
  #define SPARE5_SEL        OFFSET_OF (GDT_ENTRIES, Spare5)
  
  #if defined (MDE_CPU_IA32)
  #define CPU_CODE_SEL LINEAR_CODE_SEL
  #define CPU_DATA_SEL LINEAR_SEL
  #elif defined (MDE_CPU_X64)
  #define CPU_CODE_SEL LINEAR_CODE64_SEL
  #define CPU_DATA_SEL LINEAR_DATA64_SEL
  #else
  #error CPU type not supported for CPU GDT initialization!
  #endif
  
  #endif // _CPU_GDT_H_
  
  