mirror of https://github.com/acidanthera/audk.git
107 lines
3.4 KiB
C
107 lines
3.4 KiB
C
|
/** @file
|
||
|
|
Execute 32-bit code in Long Mode
|
||
|
|
Provide a thunk function to transition from long mode to compatibility mode to execute 32-bit code and then transit
|
||
|
|
back to long mode.
|
||
|
|
|
||
|
|
Copyright (c) 2010, 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.
|
||
|
|
|
||
|
|
**/
|
||
|
|
#include "ScriptSave.h"
|
||
|
|
|
||
|
|
#pragma pack(1)
|
||
|
|
typedef union {
|
||
|
|
struct {
|
||
|
|
UINT32 LimitLow : 16;
|
||
|
|
UINT32 BaseLow : 16;
|
||
|
|
UINT32 BaseMid : 8;
|
||
|
|
UINT32 Type : 4;
|
||
|
|
UINT32 System : 1;
|
||
|
|
UINT32 Dpl : 2;
|
||
|
|
UINT32 Present : 1;
|
||
|
|
UINT32 LimitHigh : 4;
|
||
|
|
UINT32 Software : 1;
|
||
|
|
UINT32 Reserved : 1;
|
||
|
|
UINT32 DefaultSize : 1;
|
||
|
|
UINT32 Granularity : 1;
|
||
|
|
UINT32 BaseHigh : 8;
|
||
|
|
} Bits;
|
||
|
|
UINT64 Uint64;
|
||
|
|
} IA32_GDT;
|
||
|
|
#pragma pack()
|
||
|
|
|
||
|
|
//
|
||
|
|
// Global Descriptor Table (GDT)
|
||
|
|
//
|
||
|
|
GLOBAL_REMOVE_IF_UNREFERENCED IA32_GDT mGdtEntries[] = {
|
||
|
|
{{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}}, /* 0x0: reserve */
|
||
|
|
{{0xFFFF, 0, 0, 0xB, 1, 0, 1, 0xF, 0, 0, 1, 1, 0}}, /* 0x8: compatibility mode */
|
||
|
|
{{0xFFFF, 0, 0, 0xB, 1, 0, 1, 0xF, 0, 1, 0, 1, 0}}, /* 0x10: for long mode */
|
||
|
|
{{0xFFFF, 0, 0, 0x3, 1, 0, 1, 0xF, 0, 0, 1, 1, 0}}, /* 0x18: data */
|
||
|
|
{{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}}, /* 0x20: reserve */
|
||
|
|
};
|
||
|
|
|
||
|
|
//
|
||
|
|
// IA32 Gdt register
|
||
|
|
//
|
||
|
|
GLOBAL_REMOVE_IF_UNREFERENCED IA32_DESCRIPTOR mGdt = {
|
||
|
|
sizeof (mGdtEntries) - 1,
|
||
|
|
(UINTN) mGdtEntries
|
||
|
|
};
|
||
|
|
/**
|
||
|
|
Assembly function to transition from long mode to compatibility mode to execute 32-bit code and then transit back to
|
||
|
|
long mode.
|
||
|
|
@param Function The 32bit code entry to be executed.
|
||
|
|
@param Param1 The first parameter to pass to 32bit code
|
||
|
|
@param Param2 The second parameter to pass to 32bit code
|
||
|
|
@param InternalGdtr The GDT and GDT descriptor used by this library
|
||
|
|
|
||
|
|
@retval EFI_SUCCESS Execute 32bit code successfully.
|
||
|
|
@retval other Something wrong when execute the 32bit code
|
||
|
|
**/
|
||
|
|
EFI_STATUS
|
||
|
|
AsmExecute32BitCode (
|
||
|
|
IN UINT64 Function,
|
||
|
|
IN UINT64 Param1,
|
||
|
|
IN UINT64 Param2,
|
||
|
|
IN IA32_DESCRIPTOR *InternalGdtr
|
||
|
|
);
|
||
|
|
|
||
|
|
/**
|
||
|
|
Wrapper for a thunk to transition from long mode to compatibility mode to execute 32-bit code and then transit back to
|
||
|
|
long mode.
|
||
|
|
|
||
|
|
@param Function The 32bit code entry to be executed.
|
||
|
|
@param Param1 The first parameter to pass to 32bit code
|
||
|
|
@param Param2 The second parameter to pass to 32bit code
|
||
|
|
@retval EFI_SUCCESS Execute 32bit code successfully.
|
||
|
|
@retval other Something wrong when execute the 32bit code
|
||
|
|
|
||
|
|
**/
|
||
|
|
EFI_STATUS
|
||
|
|
Execute32BitCode (
|
||
|
|
IN UINT64 Function,
|
||
|
|
IN UINT64 Param1,
|
||
|
|
IN UINT64 Param2
|
||
|
|
)
|
||
|
|
{
|
||
|
|
EFI_STATUS Status;
|
||
|
|
|
||
|
|
ASSERT (Function != 0);
|
||
|
|
|
||
|
|
Status = AsmExecute32BitCode (
|
||
|
|
Function,
|
||
|
|
Param1,
|
||
|
|
Param2,
|
||
|
|
&mGdt
|
||
|
|
);
|
||
|
|
return Status;
|
||
|
|
}
|
||
|
|
|