UefiCpuPkg/Library/MpInitLib/Microcode.c

   1 /** @file
   2   Implementation of loading microcode on processors.
   3
   4   Copyright (c) 2015 - 2017, Intel Corporation. All rights reserved.<BR>
   5   This program and the accompanying materials
   6   are licensed and made available under the terms and conditions of the BSD License
   7   which accompanies this distribution.  The full text of the license may be found at
   8   http://opensource.org/licenses/bsd-license.php
   9
  10   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13 **/
  14
  15 #include "MpLib.h"
  16
  17 /**
  18   Get microcode update signature of currently loaded microcode update.
  19
  20   @return  Microcode signature.
  21 **/
  22 UINT32
  23 GetCurrentMicrocodeSignature (
  24   VOID
  25   )
  26 {
  27   MSR_IA32_BIOS_SIGN_ID_REGISTER   BiosSignIdMsr;
  28
  29   AsmWriteMsr64 (MSR_IA32_BIOS_SIGN_ID, 0);
  30   AsmCpuid (CPUID_VERSION_INFO, NULL, NULL, NULL, NULL);
  31   BiosSignIdMsr.Uint64 = AsmReadMsr64 (MSR_IA32_BIOS_SIGN_ID);
  32   return BiosSignIdMsr.Bits.MicrocodeUpdateSignature;
  33 }
  34
  35 /**
  36   Detect whether specified processor can find matching microcode patch and load it.
  37
  38   @param[in]  CpuMpData  The pointer to CPU MP Data structure.
  39 **/
  40 VOID
  41 MicrocodeDetect (
  42   IN CPU_MP_DATA             *CpuMpData
  43   )
  44 {
  45   UINT32                                  ExtendedTableLength;
  46   UINT32                                  ExtendedTableCount;
  47   CPU_MICROCODE_EXTENDED_TABLE            *ExtendedTable;
  48   CPU_MICROCODE_EXTENDED_TABLE_HEADER     *ExtendedTableHeader;
  49   CPU_MICROCODE_HEADER                    *MicrocodeEntryPoint;
  50   UINTN                                   MicrocodeEnd;
  51   UINTN                                   Index;
  52   UINT8                                   PlatformId;
  53   CPUID_VERSION_INFO_EAX                  Eax;
  54   UINT32                                  CurrentRevision;
  55   UINT32                                  LatestRevision;
  56   UINTN                                   TotalSize;
  57   UINT32                                  CheckSum32;
  58   BOOLEAN                                 CorrectMicrocode;
  59   VOID                                    *MicrocodeData;
  60   MSR_IA32_PLATFORM_ID_REGISTER           PlatformIdMsr;
  61
  62   if (CpuMpData->MicrocodePatchRegionSize == 0) {
  63     //
  64     // There is no microcode patches
  65     //
  66     return;
  67   }
  68
  69   CurrentRevision = GetCurrentMicrocodeSignature ();
  70   if (CurrentRevision != 0) {
  71     //
  72     // Skip loading microcode if it has been loaded successfully
  73     //
  74     return;
  75   }
  76
  77   ExtendedTableLength = 0;
  78   //
  79   // Here data of CPUID leafs have not been collected into context buffer, so
  80   // GetProcessorCpuid() cannot be used here to retrieve sCPUID data.
  81   //
  82   AsmCpuid (CPUID_VERSION_INFO, &Eax.Uint32, NULL, NULL, NULL);
  83
  84   //
  85   // The index of platform information resides in bits 50:52 of MSR IA32_PLATFORM_ID
  86   //
  87   PlatformIdMsr.Uint64 = AsmReadMsr64 (MSR_IA32_PLATFORM_ID);
  88   PlatformId = (UINT8) PlatformIdMsr.Bits.PlatformId;
  89
  90   LatestRevision = 0;
  91   MicrocodeData  = NULL;
  92   MicrocodeEnd = (UINTN) (CpuMpData->MicrocodePatchAddress + CpuMpData->MicrocodePatchRegionSize);
  93   MicrocodeEntryPoint = (CPU_MICROCODE_HEADER *) (UINTN) CpuMpData->MicrocodePatchAddress;
  94   do {
  95     //
  96     // Check if the microcode is for the Cpu and the version is newer
  97     // and the update can be processed on the platform
  98     //
  99     CorrectMicrocode = FALSE;
 100     if (MicrocodeEntryPoint->HeaderVersion == 0x1) {
 101       //
 102       // It is the microcode header. It is not the padding data between microcode patches
 103       // because the padding data should not include 0x00000001 and it should be the repeated
 104       // byte format (like 0xXYXYXYXY....).
 105       //
 106       if (MicrocodeEntryPoint->ProcessorSignature.Uint32 == Eax.Uint32 &&
 107           MicrocodeEntryPoint->UpdateRevision > LatestRevision &&
 108           (MicrocodeEntryPoint->ProcessorFlags & (1 << PlatformId))
 109           ) {
 110         if (MicrocodeEntryPoint->DataSize == 0) {
 111           CheckSum32 = CalculateSum32 ((UINT32 *) MicrocodeEntryPoint, 2048);
 112         } else {
 113           CheckSum32 = CalculateSum32 (
 114                          (UINT32 *) MicrocodeEntryPoint,
 115                          MicrocodeEntryPoint->DataSize + sizeof (CPU_MICROCODE_HEADER)
 116                          );
 117         }
 118         if (CheckSum32 == 0) {
 119           CorrectMicrocode = TRUE;
 120         }
 121       } else if ((MicrocodeEntryPoint->DataSize != 0) &&
 122                  (MicrocodeEntryPoint->UpdateRevision > LatestRevision)) {
 123         ExtendedTableLength = MicrocodeEntryPoint->TotalSize - (MicrocodeEntryPoint->DataSize +
 124                                 sizeof (CPU_MICROCODE_HEADER));
 125         if (ExtendedTableLength != 0) {
 126           //
 127           // Extended Table exist, check if the CPU in support list
 128           //
 129           ExtendedTableHeader = (CPU_MICROCODE_EXTENDED_TABLE_HEADER *) ((UINT8 *) (MicrocodeEntryPoint)
 130                                   + MicrocodeEntryPoint->DataSize + sizeof (CPU_MICROCODE_HEADER));
 131           //
 132           // Calculate Extended Checksum
 133           //
 134           if ((ExtendedTableLength % 4) == 0) {
 135             CheckSum32 = CalculateSum32 ((UINT32 *) ExtendedTableHeader, ExtendedTableLength);
 136             if (CheckSum32 == 0) {
 137               //
 138               // Checksum correct
 139               //
 140               ExtendedTableCount = ExtendedTableHeader->ExtendedSignatureCount;
 141               ExtendedTable      = (CPU_MICROCODE_EXTENDED_TABLE *) (ExtendedTableHeader + 1);
 142               for (Index = 0; Index < ExtendedTableCount; Index ++) {
 143                 CheckSum32 = CalculateSum32 ((UINT32 *) ExtendedTable, sizeof(CPU_MICROCODE_EXTENDED_TABLE));
 144                 if (CheckSum32 == 0) {
 145                   //
 146                   // Verify Header
 147                   //
 148                   if ((ExtendedTable->ProcessorSignature.Uint32 == Eax.Uint32) &&
 149                       (ExtendedTable->ProcessorFlag & (1 << PlatformId)) ) {
 150                     //
 151                     // Find one
 152                     //
 153                     CorrectMicrocode = TRUE;
 154                     break;
 155                   }
 156                 }
 157                 ExtendedTable ++;
 158               }
 159             }
 160           }
 161         }
 162       }
 163     } else {
 164       //
 165       // It is the padding data between the microcode patches for microcode patches alignment.
 166       // Because the microcode patch is the multiple of 1-KByte, the padding data should not
 167       // exist if the microcode patch alignment value is not larger than 1-KByte. So, the microcode
 168       // alignment value should be larger than 1-KByte. We could skip SIZE_1KB padding data to
 169       // find the next possible microcode patch header.
 170       //
 171       MicrocodeEntryPoint = (CPU_MICROCODE_HEADER *) (((UINTN) MicrocodeEntryPoint) + SIZE_1KB);
 172       continue;
 173     }
 174     //
 175     // Get the next patch.
 176     //
 177     if (MicrocodeEntryPoint->DataSize == 0) {
 178       TotalSize = 2048;
 179     } else {
 180       TotalSize = MicrocodeEntryPoint->TotalSize;
 181     }
 182
 183     if (CorrectMicrocode) {
 184       LatestRevision = MicrocodeEntryPoint->UpdateRevision;
 185       MicrocodeData = (VOID *) ((UINTN) MicrocodeEntryPoint + sizeof (CPU_MICROCODE_HEADER));
 186     }
 187
 188     MicrocodeEntryPoint = (CPU_MICROCODE_HEADER *) (((UINTN) MicrocodeEntryPoint) + TotalSize);
 189   } while (((UINTN) MicrocodeEntryPoint < MicrocodeEnd));
 190
 191   if (LatestRevision > CurrentRevision) {
 192     //
 193     // BIOS only authenticate updates that contain a numerically larger revision
 194     // than the currently loaded revision, where Current Signature < New Update
 195     // Revision. A processor with no loaded update is considered to have a
 196     // revision equal to zero.
 197     //
 198     ASSERT (MicrocodeData != NULL);
 199     AsmWriteMsr64 (
 200         MSR_IA32_BIOS_UPDT_TRIG,
 201         (UINT64) (UINTN) MicrocodeData
 202         );
 203     //
 204     // Get and check new microcode signature
 205     //
 206     CurrentRevision = GetCurrentMicrocodeSignature ();
 207     if (CurrentRevision != LatestRevision) {
 208       AcquireSpinLock(&CpuMpData->MpLock);
 209       DEBUG ((EFI_D_ERROR, "Updated microcode signature [0x%08x] does not match \
 210                 loaded microcode signature [0x%08x]\n", CurrentRevision, LatestRevision));
 211       ReleaseSpinLock(&CpuMpData->MpLock);
 212     }
 213   }
 214 }