Update the copyright notice format

[mirror_edk2.git] / MdePkg / Library / BaseLib / Ia32 / WriteDr4.asm

diff --git a/MdePkg/Library/BaseLib/Ia32/WriteDr4.asm b/MdePkg/Library/BaseLib/Ia32/WriteDr4.asm
index ca9a839f7028f8a053348640221f8d373e5f89dd..dc8312e6f581c10753931fdb10f6b5e19fe95c07 100644 (file)
--- a/MdePkg/Library/BaseLib/Ia32/WriteDr4.asm
+++ b/MdePkg/Library/BaseLib/Ia32/WriteDr4.asm
@@ -1,7 +1,7 @@
 ;------------------------------------------------------------------------------\r
 ;\r
-; Copyright (c) 2006, Intel Corporation\r
-; All rights reserved. This program and the accompanying materials\r
+; Copyright (c) 2006, Intel Corporation. All rights reserved.<BR>\r
+; This program and the accompanying materials\r
 ; are licensed and made available under the terms and conditions of the BSD License\r
 ; which accompanies this distribution.  The full text of the license may be found at\r
 ; http://opensource.org/licenses/bsd-license.php\r
@@ -34,6 +34,13 @@
 ;------------------------------------------------------------------------------\r
 AsmWriteDr4 PROC\r
     mov     eax, [esp + 4]\r
+    ;\r
+    ; DR4 is alias to DR6 only if DE (in CR4) is cleared. Otherwise, writing to\r
+    ; this register will cause a #UD exception.\r
+    ;\r
+    ; MS assembler doesn't support this instruction since no one would use it\r
+    ; under normal circustances. Here opcode is used.\r
+    ;\r
     DB      0fh, 23h, 0e0h\r
     ret\r
 AsmWriteDr4 ENDP\r