summaryrefslogtreecommitdiff
path: root/MdePkg/Library/BaseLib/Ia32/ReadDr5.asm
diff options
context:
space:
mode:
authorvanjeff <vanjeff@6f19259b-4bc3-4df7-8a09-765794883524>2007-06-22 03:21:45 +0000
committervanjeff <vanjeff@6f19259b-4bc3-4df7-8a09-765794883524>2007-06-22 03:21:45 +0000
commite1f414b6a7d8a0424e0e01f655b09a4612b4d0e8 (patch)
tree32d74f9463f0b5c6a28ff6aff73709219d437604 /MdePkg/Library/BaseLib/Ia32/ReadDr5.asm
parente053747a04ad7b8d71c7593b93e1575ba0057a91 (diff)
downloadedk2-platforms-e1f414b6a7d8a0424e0e01f655b09a4612b4d0e8.tar.xz
Import some basic libraries instances for Mde Packages.
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@2704 6f19259b-4bc3-4df7-8a09-765794883524
Diffstat (limited to 'MdePkg/Library/BaseLib/Ia32/ReadDr5.asm')
-rw-r--r--MdePkg/Library/BaseLib/Ia32/ReadDr5.asm47
1 files changed, 47 insertions, 0 deletions
diff --git a/MdePkg/Library/BaseLib/Ia32/ReadDr5.asm b/MdePkg/Library/BaseLib/Ia32/ReadDr5.asm
new file mode 100644
index 0000000000..091792dab9
--- /dev/null
+++ b/MdePkg/Library/BaseLib/Ia32/ReadDr5.asm
@@ -0,0 +1,47 @@
+;------------------------------------------------------------------------------
+;
+; Copyright (c) 2006, Intel Corporation
+; All rights reserved. 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.
+;
+; Module Name:
+;
+; ReadDr5.Asm
+;
+; Abstract:
+;
+; AsmReadDr5 function
+;
+; Notes:
+;
+;------------------------------------------------------------------------------
+
+ .586p
+ .model flat,C
+ .code
+
+;------------------------------------------------------------------------------
+; UINTN
+; EFIAPI
+; AsmReadDr5 (
+; VOID
+; );
+;------------------------------------------------------------------------------
+AsmReadDr5 PROC
+ ;
+ ; DR5 is alias to DR7 only if DE (in CR4) is cleared. Otherwise, reading
+ ; this register will cause a #UD exception.
+ ;
+ ; MS assembler doesn't support this instruction since no one would use it
+ ; under normal circustances. Here opcode is used.
+ ;
+ DB 0fh, 21h, 0e8h
+ ret
+AsmReadDr5 ENDP
+
+ END