UefiCpuPkg/MtrrLib: Add worker functions not invoke IsMtrrSupported()

Abstract some worker functions not to invoke IsMtrrSupported(). They could be
used by other functions to reduce the number of invoking times on
IsMtrrSupported().

Cc: Feng Tian <feng.tian@intel.com>
Cc: Michael Kinney <michael.d.kinney@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Michael Kinney <michael.d.kinney@intel.com>
Signed-off-by: Jeff Fan <jeff.fan@intel.com>
Reviewed-by: Feng Tian <feng.tian@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@19153 6f19259b-4bc3-4df7-8a09-765794883524

UefiCpuPkg/Library/MtrrLib/MtrrLib.c

@@ -103,6 +103,24 @@ GLOBAL_REMOVE_IF_UNREFERENCED CONST CHAR8 *mMtrrMemoryCacheTypeShortName[] = {
   "R*"   // Invalid
 };
 
+/**
+  Worker function returns the variable MTRR count for the CPU.
+
+  @return Variable MTRR count
+
+**/
+UINT32
+GetVariableMtrrCountWorker (
+  VOID
+  )
+{
+  UINT32  VariableMtrrCount;
+
+  VariableMtrrCount = (UINT32)(AsmReadMsr64 (MTRR_LIB_IA32_MTRR_CAP) & MTRR_LIB_IA32_MTRR_CAP_VCNT_MASK);
+  ASSERT (VariableMtrrCount <= MTRR_NUMBER_OF_VARIABLE_MTRR);
+  return VariableMtrrCount;
+}
+
 /**
   Returns the variable MTRR count for the CPU.
 
@@ -115,16 +133,33 @@ GetVariableMtrrCount (
   VOID
   )
 {
-  UINT32  VariableMtrrCount;
-
   if (!IsMtrrSupported ()) {
     return 0;
   }
+  return GetVariableMtrrCountWorker ();
+}
 
-  VariableMtrrCount = (UINT32)(AsmReadMsr64 (MTRR_LIB_IA32_MTRR_CAP) & MTRR_LIB_IA32_MTRR_CAP_VCNT_MASK);
-  ASSERT (VariableMtrrCount <= MTRR_NUMBER_OF_VARIABLE_MTRR);
+/**
+  Worker function returns the firmware usable variable MTRR count for the CPU.
 
-  return VariableMtrrCount;
+  @return Firmware usable variable MTRR count
+
+**/
+UINT32
+GetFirmwareVariableMtrrCountWorker (
+  VOID
+  )
+{
+  UINT32  VariableMtrrCount;
+  UINT32  ReservedMtrrNumber;
+
+  VariableMtrrCount = GetVariableMtrrCountWorker ();
+  ReservedMtrrNumber = PcdGet32 (PcdCpuNumberOfReservedVariableMtrrs);
+  if (VariableMtrrCount < ReservedMtrrNumber) {
+    return 0;
+  }
+
+  return VariableMtrrCount - ReservedMtrrNumber;
 }
 
 /**
@@ -139,18 +174,27 @@ GetFirmwareVariableMtrrCount (
   VOID
   )
 {
-  UINT32  VariableMtrrCount;
-  UINT32  ReservedMtrrNumber;
-
-  VariableMtrrCount = GetVariableMtrrCount ();
-  ReservedMtrrNumber = PcdGet32 (PcdCpuNumberOfReservedVariableMtrrs);
-  if (VariableMtrrCount < ReservedMtrrNumber) {
+  if (!IsMtrrSupported ()) {
     return 0;
   }
-
-  return VariableMtrrCount - ReservedMtrrNumber;
+  return GetFirmwareVariableMtrrCountWorker ();
 }
 
+/**
+  Worker function returns the default MTRR cache type for the system.
+
+  @return  The default MTRR cache type.
+
+**/
+MTRR_MEMORY_CACHE_TYPE
+MtrrGetDefaultMemoryTypeWorker (
+  VOID
+  )
+{
+  return (MTRR_MEMORY_CACHE_TYPE) (AsmReadMsr64 (MTRR_LIB_IA32_MTRR_DEF_TYPE) & 0x7);
+}
+
+
 /**
   Returns the default MTRR cache type for the system.
 
@@ -166,8 +210,7 @@ MtrrGetDefaultMemoryType (
   if (!IsMtrrSupported ()) {
     return CacheUncacheable;
   }
-
-  return (MTRR_MEMORY_CACHE_TYPE) (AsmReadMsr64 (MTRR_LIB_IA32_MTRR_DEF_TYPE) & 0x7);
+  return MtrrGetDefaultMemoryTypeWorker ();
 }
 
 /**
@@ -1290,26 +1333,21 @@ MtrrGetMemoryAttribute (
 
 
 /**
-  This function will get the raw value in variable MTRRs
+  Worker function will get the raw value in variable MTRRs
 
-  @param[out]  FixedSettings  A buffer to hold fixed MTRRs content.
+  @param[out] VariableSettings   A buffer to hold variable MTRRs content.
 
   @return The VariableSettings input pointer
 
 **/
 MTRR_VARIABLE_SETTINGS*
-EFIAPI
-MtrrGetVariableMtrr (
-  OUT MTRR_VARIABLE_SETTINGS         *VariableSettings
+MtrrGetVariableMtrrWorker (
+  OUT MTRR_VARIABLE_SETTINGS  *VariableSettings
   )
 {
   UINT32  Index;
   UINT32  VariableMtrrCount;
 
-  if (!IsMtrrSupported ()) {
-    return VariableSettings;
-  }
-
   VariableMtrrCount = GetVariableMtrrCount ();
   ASSERT (VariableMtrrCount <= MTRR_NUMBER_OF_VARIABLE_MTRR);
 
@@ -1323,6 +1361,29 @@ MtrrGetVariableMtrr (
   return  VariableSettings;
 }
 
+/**
+  This function will get the raw value in variable MTRRs
+
+  @param[out]  VariableSettings   A buffer to hold variable MTRRs content.
+
+  @return The VariableSettings input pointer
+
+**/
+MTRR_VARIABLE_SETTINGS*
+EFIAPI
+MtrrGetVariableMtrr (
+  OUT MTRR_VARIABLE_SETTINGS         *VariableSettings
+  )
+{
+  if (!IsMtrrSupported ()) {
+    return VariableSettings;
+  }
+
+  return MtrrGetVariableMtrrWorker (
+           VariableSettings
+           );
+}
+
 
 /**
   Worker function setting variable MTRRs
@@ -1380,11 +1441,34 @@ MtrrSetVariableMtrr (
   return  VariableSettings;
 }
 
+/**
+  Worker function gets the content in fixed MTRRs
+
+  @param[out]  FixedSettings  A buffer to hold fixed MTRRs content.
+
+  @retval The pointer of FixedSettings
+
+**/
+MTRR_FIXED_SETTINGS*
+MtrrGetFixedMtrrWorker (
+  OUT MTRR_FIXED_SETTINGS         *FixedSettings
+  )
+{
+  UINT32  Index;
+
+  for (Index = 0; Index < MTRR_NUMBER_OF_FIXED_MTRR; Index++) {
+      FixedSettings->Mtrr[Index] =
+        AsmReadMsr64 (mMtrrLibFixedMtrrTable[Index].Msr);
+  }
+
+  return FixedSettings;
+}
+
 
 /**
   This function gets the content in fixed MTRRs
 
-  @param[out]  FixedSettings  A buffer to hold fixed Mtrrs content.
+  @param[out]  FixedSettings  A buffer to hold fixed MTRRs content.
 
   @retval The pointer of FixedSettings
 
@@ -1395,18 +1479,11 @@ MtrrGetFixedMtrr (
   OUT MTRR_FIXED_SETTINGS         *FixedSettings
   )
 {
-  UINT32  Index;
-
   if (!IsMtrrSupported ()) {
     return FixedSettings;
   }
 
-  for (Index = 0; Index < MTRR_NUMBER_OF_FIXED_MTRR; Index++) {
-      FixedSettings->Mtrr[Index] =
-        AsmReadMsr64 (mMtrrLibFixedMtrrTable[Index].Msr);
-  };
-
-  return FixedSettings;
+  return MtrrGetFixedMtrrWorker (FixedSettings);
 }
 
 /**