UefiCpuPkg/CpuTimerDxeRiscV64: Use DT based timer frequency in Timer driver

There is GetPerformanceCounterProperties() that relies
on Device Tree to fetch timer frequency and removes the
dependency from the PCDs, use that instead.

Signed-off-by: Akshay Behl <cap2k4@rivosinc.com>

Co-authored-by: Dhaval Sharma <dhaval@rivosinc.com>

UefiCpuPkg/CpuTimerDxeRiscV64/CpuTimerDxeRiscV64.inf

@@ -32,6 +32,7 @@
   CpuLib
   UefiBootServicesTableLib
   UefiDriverEntryPoint
+  TimerLib
 
 [LibraryClasses.RISCV64]
   RiscVSbiLib
@@ -42,7 +43,6 @@
 
 [Pcd]
   gEfiMdePkgTokenSpaceGuid.PcdRiscVFeatureOverride           ## CONSUMES
-  gUefiCpuPkgTokenSpaceGuid.PcdCpuCoreCrystalClockFrequency  ## CONSUMES
 
 [Protocols]
   gEfiCpuArchProtocolGuid       ## CONSUMES

UefiCpuPkg/CpuTimerDxeRiscV64/Timer.c

@@ -10,6 +10,7 @@
 #include <Library/BaseLib.h>
 #include <Library/BaseRiscVSbiLib.h>
 #include <Library/UefiLib.h>
+#include <Library/TimerLib.h>
 #include "Timer.h"
 
 //
@@ -114,7 +115,7 @@ TimerInterruptHandler (
     mTimerNotifyFunction (
       DivU64x32 (
         EFI_TIMER_PERIOD_SECONDS (PeriodStart - mLastPeriodStart),
-        PcdGet64 (PcdCpuCoreCrystalClockFrequency)
+        GetPerformanceCounterProperties (NULL, NULL)
         )
       );
   }
@@ -129,7 +130,7 @@ TimerInterruptHandler (
   PeriodStart     += DivU64x32 (
                        MultU64x32 (
                          mTimerPeriod,
-                         PcdGet64 (PcdCpuCoreCrystalClockFrequency)
+                         GetPerformanceCounterProperties (NULL, NULL)
                          ),
                        1000000u
                        );  // convert to tick
@@ -232,7 +233,7 @@ TimerDriverSetTimerPeriod (
   PeriodStart     += DivU64x32 (
                        MultU64x32 (
                          mTimerPeriod,
-                         PcdGet64 (PcdCpuCoreCrystalClockFrequency)
+                         GetPerformanceCounterProperties (NULL, NULL)
                          ),
                        1000000u
                        ); // convert to tick