[Patch] UefiCpuPkg/MpInitLib: Avoid call PcdGe* in Ap & Bsp.

[Eric Dong <eric.dong@intel.com>]

MicrocodeDetect function will run by every threads, and it will
use PcdGet to get PcdCpuMicrocodePatchAddress and
PcdCpuMicrocodePatchRegionSize, if change both PCD default to dynamic,
system will in non-deterministic behavior.

By design, UEFI/PI services are single threaded and not re-entrant
so Multi processor code should not use UEFI/PI services. Here, Pcd
protocol/PPI is used to access dynamic PCDs so it would result in
non-deterministic behavior.

This code get PCD value in BSP and save them in CPU_MP_DATA for Ap.

https://bugzilla.tianocore.org/show_bug.cgi?id=726

Cc: Crystal Lee <CrystalLee@ami.com.tw>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Eric Dong <eric.dong@intel.com>
---
 UefiCpuPkg/Library/MpInitLib/Microcode.c | 10 +++-------
 UefiCpuPkg/Library/MpInitLib/MpLib.c     |  2 ++
 UefiCpuPkg/Library/MpInitLib/MpLib.h     |  2 ++
 3 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/UefiCpuPkg/Library/MpInitLib/Microcode.c b/UefiCpuPkg/Library/MpInitLib/Microcode.c
index 982995b..35f66f7 100644
--- a/UefiCpuPkg/Library/MpInitLib/Microcode.c
+++ b/UefiCpuPkg/Library/MpInitLib/Microcode.c
@@ -42,8 +42,6 @@ MicrocodeDetect (
   IN CPU_MP_DATA             *CpuMpData
   )
 {
-  UINT64                                  MicrocodePatchAddress;
-  UINT64                                  MicrocodePatchRegionSize;
   UINT32                                  ExtendedTableLength;
   UINT32                                  ExtendedTableCount;
   CPU_MICROCODE_EXTENDED_TABLE            *ExtendedTable;
@@ -61,9 +59,7 @@ MicrocodeDetect (
   VOID                                    *MicrocodeData;
   MSR_IA32_PLATFORM_ID_REGISTER           PlatformIdMsr;
 
-  MicrocodePatchAddress    = PcdGet64 (PcdCpuMicrocodePatchAddress);
-  MicrocodePatchRegionSize = PcdGet64 (PcdCpuMicrocodePatchRegionSize);
-  if (MicrocodePatchRegionSize == 0) {
+  if (CpuMpData->MicrocodePatchRegionSize == 0) {
     //
     // There is no microcode patches
     //
@@ -93,8 +89,8 @@ MicrocodeDetect (
 
   LatestRevision = 0;
   MicrocodeData  = NULL;
-  MicrocodeEnd = (UINTN) (MicrocodePatchAddress + MicrocodePatchRegionSize);
-  MicrocodeEntryPoint = (CPU_MICROCODE_HEADER *) (UINTN) MicrocodePatchAddress;
+  MicrocodeEnd = (UINTN) (CpuMpData->MicrocodePatchAddress + CpuMpData->MicrocodePatchRegionSize);
+  MicrocodeEntryPoint = (CPU_MICROCODE_HEADER *) (UINTN) CpuMpData->MicrocodePatchAddress;
   do {
     //
     // Check if the microcode is for the Cpu and the version is newer
diff --git a/UefiCpuPkg/Library/MpInitLib/MpLib.c b/UefiCpuPkg/Library/MpInitLib/MpLib.c
index 924b909..f3ee6d4 100644
--- a/UefiCpuPkg/Library/MpInitLib/MpLib.c
+++ b/UefiCpuPkg/Library/MpInitLib/MpLib.c
@@ -1458,6 +1458,8 @@ MpInitLibInitialize (
   CpuMpData->SwitchBspFlag    = FALSE;
   CpuMpData->CpuData          = (CPU_AP_DATA *) (CpuMpData + 1);
   CpuMpData->CpuInfoInHob     = (UINT64) (UINTN) (CpuMpData->CpuData + MaxLogicalProcessorNumber);
+  CpuMpData->MicrocodePatchAddress    = PcdGet64 (PcdCpuMicrocodePatchAddress);
+  CpuMpData->MicrocodePatchRegionSize = PcdGet64 (PcdCpuMicrocodePatchRegionSize);
   InitializeSpinLock(&CpuMpData->MpLock);
   //
   // Save BSP's Control registers to APs
diff --git a/UefiCpuPkg/Library/MpInitLib/MpLib.h b/UefiCpuPkg/Library/MpInitLib/MpLib.h
index 19defda..84ae24f 100644
--- a/UefiCpuPkg/Library/MpInitLib/MpLib.h
+++ b/UefiCpuPkg/Library/MpInitLib/MpLib.h
@@ -233,6 +233,8 @@ struct _CPU_MP_DATA {
   UINT8                          Vector;
   BOOLEAN                        PeriodicMode;
   BOOLEAN                        TimerInterruptState;
+  UINT64                         MicrocodePatchAddress;
+  UINT64                         MicrocodePatchRegionSize;
 };
 
 extern EFI_GUID mCpuInitMpLibHobGuid;
-- 
2.7.0.windows.1