1 /*++ 2 3 Copyright (c) 2006, Intel Corporation. All rights reserved.<BR> 4 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 #include EFI_PROTOCOL_DEFINITION (LegacyBios) 43 44 #define EFI_LEGACY_BIOS_THUNK_PROTOCOL_GUID \ 45 { \ 46 0x4c51a7ba, 0x7195, 0x442d, {0x87, 0x92, 0xbe, 0xea, 0x6e, 0x2f, 0xf6, 0xec} \ 47 } 48 49 EFI_FORWARD_DECLARATION (EFI_LEGACY_BIOS_THUNK_PROTOCOL); 50 51 typedef 52 BOOLEAN 53 (EFIAPI *EFI_LEGACY_BIOS_THUNK_INT86) ( 54 IN EFI_LEGACY_BIOS_THUNK_PROTOCOL * This, 55 IN UINT8 BiosInt, 56 IN OUT EFI_IA32_REGISTER_SET * Regs 57 ) 58 /*++ 59 60 Routine Description: 61 Thunk to 16-bit real mode and execute a software interrupt with a vector 62 of BiosInt. Regs will contain the 16-bit register context on entry and 63 exit. 64 65 Arguments: 66 This - Protocol instance pointer. 67 BiosInt - Processor interrupt vector to invoke 68 Reg - Register contexted passed into (and returned) from thunk to 69 16-bit mode 70 71 Returns: 72 FALSE - Thunk completed, and there were no BIOS errors in the target code. 73 See Regs for status. 74 TRUE - There was a BIOS erro in the target code. 75 76 --*/ 77 ; 78 79 typedef 80 BOOLEAN 81 (EFIAPI *EFI_LEGACY_BIOS_THUNK_FARCALL86) ( 82 IN EFI_LEGACY_BIOS_THUNK_PROTOCOL * This, 83 IN UINT16 Segment, 84 IN UINT16 Offset, 85 IN EFI_IA32_REGISTER_SET * Regs, 86 IN VOID *Stack, 87 IN UINTN StackSize 88 ) 89 /*++ 90 91 Routine Description: 92 Thunk to 16-bit real mode and call Segment:Offset. Regs will contain the 93 16-bit register context on entry and exit. Arguments can be passed on 94 the Stack argument 95 96 Arguments: 97 This - Protocol instance pointer. 98 Segment - Segemnt of 16-bit mode call 99 Offset - Offset of 16-bit mdoe call 100 Reg - Register contexted passed into (and returned) from thunk to 101 16-bit mode 102 Stack - Caller allocated stack used to pass arguments 103 StackSize - Size of Stack in bytes 104 105 Returns: 106 FALSE - Thunk completed, and there were no BIOS errors in the target code. 107 See Regs for status. 108 TRUE - There was a BIOS erro in the target code. 109 110 --*/ 111 ; 112 113 struct _EFI_LEGACY_BIOS_THUNK_PROTOCOL { 114 EFI_LEGACY_BIOS_THUNK_INT86 Int86; 115 EFI_LEGACY_BIOS_THUNK_FARCALL86 FarCall86; 116 }; 117 118 extern EFI_GUID gEfiLegacyBiosThunkProtocolGuid; 119 120 #endif 121
