[Patch v2 2/3] UefiCpuPkg/MpInitLib: Use BSP uCode for APs if possible.

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

Search uCode costs much time, if AP has same processor type
with BSP, AP can use BSP saved uCode info to get better performance.

This change enables this solution.

Cc: Laszlo Ersek <lersek@redhat.com>
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 | 34 +++++++++++++++++++++++++++++---
 UefiCpuPkg/Library/MpInitLib/MpLib.c     |  4 ++--
 UefiCpuPkg/Library/MpInitLib/MpLib.h     | 11 +++++++++--
 3 files changed, 42 insertions(+), 7 deletions(-)

diff --git a/UefiCpuPkg/Library/MpInitLib/Microcode.c b/UefiCpuPkg/Library/MpInitLib/Microcode.c
index e47f9f4f8f..351975e2a2 100644
--- a/UefiCpuPkg/Library/MpInitLib/Microcode.c
+++ b/UefiCpuPkg/Library/MpInitLib/Microcode.c
@@ -35,11 +35,13 @@ GetCurrentMicrocodeSignature (
 /**
   Detect whether specified processor can find matching microcode patch and load it.
 
-  @param[in]  CpuMpData  The pointer to CPU MP Data structure.
+  @param[in]  CpuMpData    The pointer to CPU MP Data structure.
+  @param[in]  IsBspCallIn  Indicate whether the caller is BSP or not.
 **/
 VOID
 MicrocodeDetect (
-  IN CPU_MP_DATA             *CpuMpData
+  IN CPU_MP_DATA             *CpuMpData,
+  IN BOOLEAN                 IsBspCallIn
   )
 {
   UINT32                                  ExtendedTableLength;
@@ -58,6 +60,7 @@ MicrocodeDetect (
   BOOLEAN                                 CorrectMicrocode;
   VOID                                    *MicrocodeData;
   MSR_IA32_PLATFORM_ID_REGISTER           PlatformIdMsr;
+  UINT32                                  ProcessorFlags;
 
   if (CpuMpData->MicrocodePatchRegionSize == 0) {
     //
@@ -67,7 +70,7 @@ MicrocodeDetect (
   }
 
   CurrentRevision = GetCurrentMicrocodeSignature ();
-  if (CurrentRevision != 0) {
+  if (CurrentRevision != 0 && !IsBspCallIn) {
     //
     // Skip loading microcode if it has been loaded successfully
     //
@@ -87,6 +90,19 @@ MicrocodeDetect (
   PlatformIdMsr.Uint64 = AsmReadMsr64 (MSR_IA32_PLATFORM_ID);
   PlatformId = (UINT8) PlatformIdMsr.Bits.PlatformId;
 
+  //
+  // Check whether AP has same processor with BSP.
+  // If yes, direct use microcode info saved by BSP.
+  //
+  if (!IsBspCallIn) {
+    if ((CpuMpData->ProcessorSignature == Eax.Uint32) &&
+        (CpuMpData->ProcessorFlags & (1 << PlatformId)) != 0) {
+        MicrocodeData = (VOID *)(UINTN) CpuMpData->MicrocodeDataAddress;
+        LatestRevision = CpuMpData->MicrocodeRevision;
+        goto Done;
+    }
+  }
+
   LatestRevision = 0;
   MicrocodeData  = NULL;
   MicrocodeEnd = (UINTN) (CpuMpData->MicrocodePatchAddress + CpuMpData->MicrocodePatchRegionSize);
@@ -117,6 +133,7 @@ MicrocodeDetect (
         }
         if (CheckSum32 == 0) {
           CorrectMicrocode = TRUE;
+          ProcessorFlags = MicrocodeEntryPoint->ProcessorFlags;
         }
       } else if ((MicrocodeEntryPoint->DataSize != 0) &&
                  (MicrocodeEntryPoint->UpdateRevision > LatestRevision)) {
@@ -151,6 +168,7 @@ MicrocodeDetect (
                     // Find one
                     //
                     CorrectMicrocode = TRUE;
+                    ProcessorFlags = ExtendedTable->ProcessorFlag;
                     break;
                   }
                 }
@@ -188,6 +206,7 @@ MicrocodeDetect (
     MicrocodeEntryPoint = (CPU_MICROCODE_HEADER *) (((UINTN) MicrocodeEntryPoint) + TotalSize);
   } while (((UINTN) MicrocodeEntryPoint < MicrocodeEnd));
 
+Done:
   if (LatestRevision > CurrentRevision) {
     //
     // BIOS only authenticate updates that contain a numerically larger revision
@@ -211,4 +230,13 @@ MicrocodeDetect (
       ReleaseSpinLock(&CpuMpData->MpLock);
     }
   }
+
+  if (IsBspCallIn && (LatestRevision != 0)) {
+    CpuMpData->ProcessorSignature = Eax.Uint32;
+    CpuMpData->ProcessorFlags = ProcessorFlags;
+    CpuMpData->MicrocodeDataAddress = (UINTN) MicrocodeData;
+    CpuMpData->MicrocodeRevision = LatestRevision;
+    DEBUG ((DEBUG_INFO, "BSP Microcode:: signature [0x%08x], ProcessorFlags [0x%08x], \
+       MicroData [0x%08x], Revision [0x%08x]\n", Eax.Uint32, ProcessorFlags, (UINTN) MicrocodeData, LatestRevision));
+  }
 }
diff --git a/UefiCpuPkg/Library/MpInitLib/MpLib.c b/UefiCpuPkg/Library/MpInitLib/MpLib.c
index c3cd6d7d51..3a7bdfa00b 100644
--- a/UefiCpuPkg/Library/MpInitLib/MpLib.c
+++ b/UefiCpuPkg/Library/MpInitLib/MpLib.c
@@ -410,7 +410,7 @@ ApInitializeSync (
   //
   // Load microcode on AP
   //
-  MicrocodeDetect (CpuMpData);
+  MicrocodeDetect (CpuMpData, FALSE);
   //
   // Sync BSP's MTRR table to AP
   //
@@ -1659,7 +1659,7 @@ MpInitLibInitialize (
   //
   // Load Microcode on BSP
   //
-  MicrocodeDetect (CpuMpData);
+  MicrocodeDetect (CpuMpData, TRUE);
   //
   // Store BSP's MTRR setting
   //
diff --git a/UefiCpuPkg/Library/MpInitLib/MpLib.h b/UefiCpuPkg/Library/MpInitLib/MpLib.h
index 9aedb52636..6958080ac1 100644
--- a/UefiCpuPkg/Library/MpInitLib/MpLib.h
+++ b/UefiCpuPkg/Library/MpInitLib/MpLib.h
@@ -245,6 +245,11 @@ struct _CPU_MP_DATA {
   BOOLEAN                        TimerInterruptState;
   UINT64                         MicrocodePatchAddress;
   UINT64                         MicrocodePatchRegionSize;
+
+  UINT32                         ProcessorSignature;
+  UINT32                         ProcessorFlags;
+  UINT64                         MicrocodeDataAddress;
+  UINT32                         MicrocodeRevision;
 };
 
 extern EFI_GUID mCpuInitMpLibHobGuid;
@@ -546,11 +551,13 @@ CheckAndUpdateApsStatus (
 /**
   Detect whether specified processor can find matching microcode patch and load it.
 
-  @param[in]  CpuMpData  The pointer to CPU MP Data structure.
+  @param[in]  CpuMpData    The pointer to CPU MP Data structure.
+  @param[in]  IsBspCallIn  Indicate whether the caller is BSP or not.
 **/
 VOID
 MicrocodeDetect (
-  IN CPU_MP_DATA             *CpuMpData
+  IN CPU_MP_DATA             *CpuMpData,
+  IN BOOLEAN                 IsBspCallIn
   );
 
 /**
-- 
2.15.0.windows.1