update GetPerformanceCounterProperties() declare

[mirror_edk2.git] / MdePkg / Library / BaseTimerLibLocalApic / x86TimerLib.c

diff --git a/MdePkg/Library/BaseTimerLibLocalApic/x86TimerLib.c b/MdePkg/Library/BaseTimerLibLocalApic/x86TimerLib.c
index dd240d88d0d10a897f94473e2387205cefee4739..09b614119da174b1d272aa25bfc414935249eb13 100644 (file)
--- a/MdePkg/Library/BaseTimerLibLocalApic/x86TimerLib.c
+++ b/MdePkg/Library/BaseTimerLibLocalApic/x86TimerLib.c
@@ -239,8 +239,8 @@ GetPerformanceCounter (
 UINT64\r
 EFIAPI\r
 GetPerformanceCounterProperties (\r
-  IN      UINT64                    *StartValue,\r
-  IN      UINT64                    *EndValue\r
+  OUT      UINT64                    *StartValue,  OPTIONAL\r
+  OUT      UINT64                    *EndValue     OPTIONAL\r
   )\r
 {\r
   UINTN                             ApicBase;\r