DuetPkg/Include/Protocol/LegacyBiosThunk.h

   1 /*++
   2
   3 Copyright (c) 2006, Intel Corporation
   4 All rights reserved. This program and the accompanying materials
   5 are licensed and made available under the terms and conditions of the BSD License
   6 which accompanies this distribution.  The full text of the license may be found at
   7 http://opensource.org/licenses/bsd-license.php
   8
   9 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  10 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  11
  12 Module Name:
  13
  14   LegacyBiosThunk.h
  15
  16 Abstract:
  17
  18   The EFI Legacy BIOS Thunk Protocol is used to abstract Thunk16 call.
  19
  20   Note: The names for EFI_IA32_REGISTER_SET elements were picked to follow
  21   well known naming conventions.
  22
  23   Thunk - A thunk is a transition from one processor mode to another. A Thunk
  24           is a transition from native EFI mode to 16-bit mode. A reverse thunk
  25           would be a transition from 16-bit mode to native EFI mode.
  26
  27
  28   Note: Note: Note: Note: Note: Note: Note:
  29
  30   You most likely should not use this protocol! Find the EFI way to solve the
  31   problem to make your code portable
  32
  33   Note: Note: Note: Note: Note: Note: Note:
  34
  35 Revision History
  36
  37 --*/
  38
  39 #ifndef _EFI_LEGACY_BIOS_THUNK_H_
  40 #define _EFI_LEGACY_BIOS_THUNK_H_
  41
  42
  43 #define EFI_LEGACY_BIOS_THUNK_PROTOCOL_GUID \
  44   { \
  45     0x4c51a7ba, 0x7195, 0x442d, 0x87, 0x92, 0xbe, 0xea, 0x6e, 0x2f, 0xf6, 0xec \
  46   }
  47
  48 typedef struct _EFI_LEGACY_BIOS_THUNK_PROTOCOL EFI_LEGACY_BIOS_THUNK_PROTOCOL;
  49
  50 typedef
  51 BOOLEAN
  52 (EFIAPI *EFI_LEGACY_BIOS_THUNK_INT86) (
  53   IN EFI_LEGACY_BIOS_THUNK_PROTOCOL   * This,
  54   IN  UINT8                           BiosInt,
  55   IN OUT  EFI_IA32_REGISTER_SET       * Regs
  56   )
  57 /*++
  58
  59   Routine Description:
  60     Thunk to 16-bit real mode and execute a software interrupt with a vector
  61     of BiosInt. Regs will contain the 16-bit register context on entry and
  62     exit.
  63
  64   Arguments:
  65     This    - Protocol instance pointer.
  66     BiosInt - Processor interrupt vector to invoke
  67     Reg     - Register contexted passed into (and returned) from thunk to
  68               16-bit mode
  69
  70   Returns:
  71     FALSE   - Thunk completed, and there were no BIOS errors in the target code.
  72               See Regs for status.
  73     TRUE    - There was a BIOS erro in the target code.
  74
  75 --*/
  76 ;
  77
  78 typedef
  79 BOOLEAN
  80 (EFIAPI *EFI_LEGACY_BIOS_THUNK_FARCALL86) (
  81   IN EFI_LEGACY_BIOS_THUNK_PROTOCOL   * This,
  82   IN  UINT16                          Segment,
  83   IN  UINT16                          Offset,
  84   IN  EFI_IA32_REGISTER_SET           * Regs,
  85   IN  VOID                            *Stack,
  86   IN  UINTN                           StackSize
  87   )
  88 /*++
  89
  90   Routine Description:
  91     Thunk to 16-bit real mode and call Segment:Offset. Regs will contain the
  92     16-bit register context on entry and exit. Arguments can be passed on
  93     the Stack argument
  94
  95   Arguments:
  96     This      - Protocol instance pointer.
  97     Segment   - Segemnt of 16-bit mode call
  98     Offset    - Offset of 16-bit mdoe call
  99     Reg       - Register contexted passed into (and returned) from thunk to
 100                 16-bit mode
 101     Stack     - Caller allocated stack used to pass arguments
 102     StackSize - Size of Stack in bytes
 103
 104   Returns:
 105     FALSE     - Thunk completed, and there were no BIOS errors in the target code.
 106                 See Regs for status.
 107     TRUE      - There was a BIOS erro in the target code.
 108
 109 --*/
 110 ;
 111
 112 struct _EFI_LEGACY_BIOS_THUNK_PROTOCOL {
 113   EFI_LEGACY_BIOS_THUNK_INT86                 Int86;
 114   EFI_LEGACY_BIOS_THUNK_FARCALL86             FarCall86;
 115 };
 116
 117 extern EFI_GUID gEfiLegacyBiosThunkProtocolGuid;
 118
 119 #endif