1 /** @file
2 AsmMonitor function
3
4 Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>
5 This program and the accompanying materials
6 are licensed and made available under the terms and conditions of the BSD License
7 which accompanies this distribution. The full text of the license may be found at
8 http://opensource.org/licenses/bsd-license.php.
9
10 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
11 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
12
13 **/
14
15 /**
16 Sets up a monitor buffer that is used by AsmMwait().
17
18 Executes a MONITOR instruction with the register state specified by Eax, Ecx
19 and Edx. Returns Eax. This function is only available on IA-32 and x64.
20
21 @param RegisterEax The value to load into EAX or RAX before executing the MONITOR
22 instruction.
23 @param RegisterEcx The value to load into ECX or RCX before executing the MONITOR
24 instruction.
25 @param RegisterEdx The value to load into EDX or RDX before executing the MONITOR
26 instruction.
27
28 @return RegisterEax
29
30 **/
31 UINTN
32 EFIAPI
AsmMonitor(IN UINTN RegisterEax,IN UINTN RegisterEcx,IN UINTN RegisterEdx)33 AsmMonitor (
34 IN UINTN RegisterEax,
35 IN UINTN RegisterEcx,
36 IN UINTN RegisterEdx
37 )
38 {
39 _asm {
40 mov eax, RegisterEax
41 mov ecx, RegisterEcx
42 mov edx, RegisterEdx
43 _emit 0x0f // monitor
44 _emit 0x01
45 _emit 0xc8
46 }
47 }
48
49