MdePkg/BaseLib: Support IA32 processors without CLFLUSH

[mirror_edk2.git] / MdePkg / Library / BaseLib / Ia32 / ReadPmc.c

diff --git a/MdePkg/Library/BaseLib/Ia32/ReadPmc.c b/MdePkg/Library/BaseLib/Ia32/ReadPmc.c
index 761fa6bf4ed90025188f5dce16306b6fe6bffcda..6c6cdd8910dda4de3ed76d5846708c190add4204 100644 (file)
--- a/MdePkg/Library/BaseLib/Ia32/ReadPmc.c
+++ b/MdePkg/Library/BaseLib/Ia32/ReadPmc.c
@@ -1,30 +1,36 @@
 /** @file\r
   AsmReadPmc function\r
 \r
-  Copyright (c) 2006 - 2007, Intel Corporation<BR>\r
-  All rights reserved. This program and the accompanying materials\r
+  Copyright (c) 2006 - 2008, 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
+  http://opensource.org/licenses/bsd-license.php.\r
 \r
   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
 \r
 **/\r
 \r
-//\r
-// Include common header file for this module.\r
-//\r
+/**\r
+  Reads the current value of a Performance Counter (PMC).\r
 \r
+  Reads and returns the current value of performance counter specified by\r
+  Index. This function is only available on IA-32 and x64.\r
 \r
+  @param  Index The 32-bit Performance Counter index to read.\r
+\r
+  @return The value of the PMC specified by Index.\r
+\r
+**/\r
 UINT64\r
 EFIAPI\r
 AsmReadPmc (\r
-  IN UINT32   PmcIndex\r
+  IN UINT32   Index\r
   )\r
 {\r
   _asm {\r
-    mov     ecx, PmcIndex\r
+    mov     ecx, Index\r
     rdpmc\r
   }\r
 }\r