]>
Commit | Line | Data |
---|---|---|
e1f414b6 | 1 | /** @file\r |
2 | AsmWriteCr4 function\r | |
3 | \r | |
4 | Copyright (c) 2006 - 2007, Intel Corporation<BR>\r | |
5 | All rights reserved. This program and the accompanying materials\r | |
6 | are licensed and made available under the terms and conditions of the BSD License\r | |
7 | which accompanies this distribution. The full text of the license may be found at\r | |
8 | http://opensource.org/licenses/bsd-license.php\r | |
9 | \r | |
10 | THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r | |
11 | WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r | |
12 | \r | |
13 | **/\r | |
14 | \r | |
1efcc4ae | 15 | \r |
f734a10a | 16 | \r |
e1f414b6 | 17 | \r |
42eedea9 | 18 | /**\r |
19 | Writes a value to Control Register 4 (CR4).\r | |
20 | \r | |
21 | Writes and returns a new value to CR4. This function is only available on\r | |
22 | IA-32 and X64. This writes a 32-bit value on IA-32 and a 64-bit value on X64.\r | |
23 | \r | |
24 | @param Cr4 The value to write to CR4.\r | |
25 | \r | |
26 | @return The value written to CR4.\r | |
27 | \r | |
28 | **/\r | |
e1f414b6 | 29 | UINTN\r |
30 | EFIAPI\r | |
31 | AsmWriteCr4 (\r | |
32 | UINTN Value\r | |
33 | )\r | |
34 | {\r | |
35 | _asm {\r | |
36 | mov eax, Value\r | |
37 | _emit 0x0f // mov cr4, eax\r | |
38 | _emit 0x22\r | |
39 | _emit 0xE0\r | |
40 | }\r | |
41 | }\r | |
42 | \r |