From 850e4fe50a74142c5e03eaa326a61a6bf351f669 Mon Sep 17 00:00:00 2001
From: Jeff Fan <jeff.fan@intel.com>
Date: Fri, 1 Jul 2016 14:52:12 +0800
Subject: UefiCpuPkg/CpuMpPei: Dump message if microcode signature not matched

Verification microcode signature is one enhancement and not one requirement from
IA32 SDM. This update is just to dump debug message instead of ASSERT() if the
updated microcode signature does not match the loaded microcode signature.

Cc: Michael Kinney <michael.d.kinney@intel.com>
Cc: Feng Tian <feng.tian@intel.com>
Cc: Giri P Mudusuru <giri.p.mudusuru@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jeff Fan <jeff.fan@intel.com>
Reviewed-by: Giri P Mudusuru <giri.p.mudusuru@intel.com>
(cherry picked from commit 719ff8cf3e8f3abc967de8a0a71319ce66ff2d9d)
---
 UefiCpuPkg/CpuMpPei/CpuMpPei.c  |  4 ++--
 UefiCpuPkg/CpuMpPei/CpuMpPei.h  | 10 ++++++++++
 UefiCpuPkg/CpuMpPei/Microcode.c | 33 +++++++++++++++++++--------------
 UefiCpuPkg/CpuMpPei/Microcode.h |  9 ---------
 4 files changed, 31 insertions(+), 25 deletions(-)

diff --git a/UefiCpuPkg/CpuMpPei/CpuMpPei.c b/UefiCpuPkg/CpuMpPei/CpuMpPei.c
index 21c30bff5f..bb909bae8b 100644
--- a/UefiCpuPkg/CpuMpPei/CpuMpPei.c
+++ b/UefiCpuPkg/CpuMpPei/CpuMpPei.c
@@ -302,7 +302,7 @@ ApCFunction (
       // Sync BSP's Mtrr table to all wakeup APs and load microcode on APs.
       //
       MtrrSetAllMtrrs (&PeiCpuMpData->MtrrTable);
-      MicrocodeDetect ();
+      MicrocodeDetect (PeiCpuMpData);
       PeiCpuMpData->CpuData[ProcessorNumber].State = CpuStateIdle;
     } else {
       //
@@ -624,7 +624,7 @@ CountProcessorNumber (
   //
   // Load Microcode on BSP
   //
-  MicrocodeDetect ();
+  MicrocodeDetect (PeiCpuMpData);
   //
   // Store BSP's MTRR setting
   //
diff --git a/UefiCpuPkg/CpuMpPei/CpuMpPei.h b/UefiCpuPkg/CpuMpPei/CpuMpPei.h
index 7c8a218e0e..88465d2940 100644
--- a/UefiCpuPkg/CpuMpPei/CpuMpPei.h
+++ b/UefiCpuPkg/CpuMpPei/CpuMpPei.h
@@ -319,4 +319,14 @@ SecPlatformInformation2 (
      OUT EFI_SEC_PLATFORM_INFORMATION_RECORD2 *PlatformInformationRecord2
   );
 
+/**
+  Detect whether specified processor can find matching microcode patch and load it.
+
+  @param PeiCpuMpData        Pointer to PEI CPU MP Data
+**/
+VOID
+MicrocodeDetect (
+  IN PEI_CPU_MP_DATA            *PeiCpuMpData
+  );
+
 #endif
diff --git a/UefiCpuPkg/CpuMpPei/Microcode.c b/UefiCpuPkg/CpuMpPei/Microcode.c
index 8e7f3b0200..51a073789b 100644
--- a/UefiCpuPkg/CpuMpPei/Microcode.c
+++ b/UefiCpuPkg/CpuMpPei/Microcode.c
@@ -36,10 +36,11 @@ GetCurrentMicrocodeSignature (
 /**
   Detect whether specified processor can find matching microcode patch and load it.
 
+  @param PeiCpuMpData        Pointer to PEI CPU MP Data
 **/
 VOID
 MicrocodeDetect (
-  VOID
+  IN PEI_CPU_MP_DATA            *PeiCpuMpData
   )
 {
   UINT64                                  MicrocodePatchAddress;
@@ -187,25 +188,29 @@ MicrocodeDetect (
     MicrocodeEntryPoint = (EFI_CPU_MICROCODE_HEADER *) (((UINTN) MicrocodeEntryPoint) + TotalSize);
   } while (((UINTN) MicrocodeEntryPoint < MicrocodeEnd));
 
-  if (LatestRevision > 0) {
+  if (LatestRevision > CurrentRevision) {
     //
     // BIOS only authenticate updates that contain a numerically larger revision
     // than the currently loaded revision, where Current Signature < New Update
     // Revision. A processor with no loaded update is considered to have a
     // revision equal to zero.
     //
-    if (LatestRevision > GetCurrentMicrocodeSignature ()) {
-      AsmWriteMsr64 (
-        EFI_MSR_IA32_BIOS_UPDT_TRIG,
-        (UINT64) (UINTN) MicrocodeInfo.MicrocodeData
-        );
-      //
-      // Get and verify new microcode signature
-      //
-      ASSERT (LatestRevision == GetCurrentMicrocodeSignature ());
-      MicrocodeInfo.Load = TRUE;
-    } else {
-      MicrocodeInfo.Load = FALSE;
+    AsmWriteMsr64 (
+      EFI_MSR_IA32_BIOS_UPDT_TRIG,
+      (UINT64) (UINTN) MicrocodeInfo.MicrocodeData
+      );
+    //
+    // Get and check new microcode signature
+    //
+    CurrentRevision = GetCurrentMicrocodeSignature ();
+    if (CurrentRevision != LatestRevision) {
+      AcquireSpinLock(&PeiCpuMpData->MpLock);
+      DEBUG ((EFI_D_ERROR, "Updated microcode signature [0x%08x] does not match \
+                loaded microcode signature [0x%08x]\n", CurrentRevision, LatestRevision));
+      ReleaseSpinLock(&PeiCpuMpData->MpLock);
     }
+    MicrocodeInfo.Load = TRUE;
+  } else {
+    MicrocodeInfo.Load = FALSE;
   }
 }
diff --git a/UefiCpuPkg/CpuMpPei/Microcode.h b/UefiCpuPkg/CpuMpPei/Microcode.h
index ea686690ff..f7d23a08fd 100644
--- a/UefiCpuPkg/CpuMpPei/Microcode.h
+++ b/UefiCpuPkg/CpuMpPei/Microcode.h
@@ -56,13 +56,4 @@ typedef struct {
   UINT32  ProcessorChecksum;
 } EFI_CPU_MICROCODE_EXTENDED_TABLE;
 
-/**
-  Detect whether specified processor can find matching microcode patch and load it.
-
-**/
-VOID
-MicrocodeDetect (
-  VOID
-  );
-
 #endif
-- 
cgit v1.2.3