UefiCpuPkg/Library/MpInitLib/Microcode.c

   1 /** @file
   2   Implementation of loading microcode on processors.
   3
   4   Copyright (c) 2015 - 2016, 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] PeiCpuMpData        Pointer to PEI CPU MP Data
  39 **/
  40 VOID
  41 MicrocodeDetect (
  42   IN CPU_MP_DATA             *CpuMpData
  43   )
  44 {
  45   UINT64                                  MicrocodePatchAddress;
  46   UINT64                                  MicrocodePatchRegionSize;
  47   UINT32                                  ExtendedTableLength;
  48   UINT32                                  ExtendedTableCount;
  49   CPU_MICROCODE_EXTENDED_TABLE            *ExtendedTable;
  50   CPU_MICROCODE_EXTENDED_TABLE_HEADER     *ExtendedTableHeader;
  51   CPU_MICROCODE_HEADER                    *MicrocodeEntryPoint;
  52   UINTN                                   MicrocodeEnd;
  53   UINTN                                   Index;
  54   UINT8                                   PlatformId;
  55   CPUID_VERSION_INFO_EAX                  Eax;
  56   UINT32                                  CurrentRevision;
  57   UINT32                                  LatestRevision;
  58   UINTN                                   TotalSize;
  59   UINT32                                  CheckSum32;
  60   BOOLEAN                                 CorrectMicrocode;
  61   VOID                                    *MicrocodeData;
  62   MSR_IA32_PLATFORM_ID_REGISTER           PlatformIdMsr;
  63
  64   MicrocodePatchAddress    = PcdGet64 (PcdCpuMicrocodePatchAddress);
  65   MicrocodePatchRegionSize = PcdGet64 (PcdCpuMicrocodePatchRegionSize);
  66   if (MicrocodePatchRegionSize == 0) {
  67     //
  68     // There is no microcode patches
  69     //
  70     return;
  71   }
  72
  73   CurrentRevision = GetCurrentMicrocodeSignature ();
  74   if (CurrentRevision != 0) {
  75     //
  76     // Skip loading microcode if it has been loaded successfully
  77     //
  78     return;
  79   }
  80
  81   ExtendedTableLength = 0;
  82   //
  83   // Here data of CPUID leafs have not been collected into context buffer, so
  84   // GetProcessorCpuid() cannot be used here to retrieve sCPUID data.
  85   //
  86   AsmCpuid (CPUID_VERSION_INFO, &Eax.Uint32, NULL, NULL, NULL);
  87
  88   //
  89   // The index of platform information resides in bits 50:52 of MSR IA32_PLATFORM_ID
  90   //
  91   PlatformIdMsr.Uint64 = AsmReadMsr64 (MSR_IA32_PLATFORM_ID);
  92   PlatformId = (UINT8) PlatformIdMsr.Bits.PlatformId;
  93
  94   LatestRevision = 0;
  95   MicrocodeEnd = (UINTN) (MicrocodePatchAddress + MicrocodePatchRegionSize);
  96   MicrocodeEntryPoint = (CPU_MICROCODE_HEADER *) (UINTN) MicrocodePatchAddress;
  97   do {
  98     //
  99     // Check if the microcode is for the Cpu and the version is newer
 100     // and the update can be processed on the platform
 101     //
 102     CorrectMicrocode = FALSE;
 103     if (MicrocodeEntryPoint->HeaderVersion == 0x1) {
 104       //
 105       // It is the microcode header. It is not the padding data between microcode patches
 106       // because the padding data should not include 0x00000001 and it should be the repeated
 107       // byte format (like 0xXYXYXYXY....).
 108       //
 109       if (MicrocodeEntryPoint->ProcessorSignature.Uint32 == Eax.Uint32 &&
 110           MicrocodeEntryPoint->UpdateRevision > LatestRevision &&
 111           (MicrocodeEntryPoint->ProcessorFlags & (1 << PlatformId))
 112           ) {
 113         if (MicrocodeEntryPoint->DataSize == 0) {
 114           CheckSum32 = CalculateSum32 ((UINT32 *) MicrocodeEntryPoint, 2048);
 115         } else {
 116           CheckSum32 = CalculateSum32 (
 117                          (UINT32 *) MicrocodeEntryPoint,
 118                          MicrocodeEntryPoint->DataSize + sizeof (CPU_MICROCODE_HEADER)
 119                          );
 120         }
 121         if (CheckSum32 == 0) {
 122           CorrectMicrocode = TRUE;
 123         }
 124       } else if ((MicrocodeEntryPoint->DataSize != 0) &&
 125                  (MicrocodeEntryPoint->UpdateRevision > LatestRevision)) {
 126         ExtendedTableLength = MicrocodeEntryPoint->TotalSize - (MicrocodeEntryPoint->DataSize +
 127                                 sizeof (CPU_MICROCODE_HEADER));
 128         if (ExtendedTableLength != 0) {
 129           //
 130           // Extended Table exist, check if the CPU in support list
 131           //
 132           ExtendedTableHeader = (CPU_MICROCODE_EXTENDED_TABLE_HEADER *) ((UINT8 *) (MicrocodeEntryPoint)
 133                                   + MicrocodeEntryPoint->DataSize + sizeof (CPU_MICROCODE_HEADER));
 134           //
 135           // Calculate Extended Checksum
 136           //
 137           if ((ExtendedTableLength % 4) == 0) {
 138             CheckSum32 = CalculateSum32 ((UINT32 *) ExtendedTableHeader, ExtendedTableLength);
 139             if (CheckSum32 == 0) {
 140               //
 141               // Checksum correct
 142               //
 143               ExtendedTableCount = ExtendedTableHeader->ExtendedSignatureCount;
 144               ExtendedTable      = (CPU_MICROCODE_EXTENDED_TABLE *) (ExtendedTableHeader + 1);
 145               for (Index = 0; Index < ExtendedTableCount; Index ++) {
 146                 CheckSum32 = CalculateSum32 ((UINT32 *) ExtendedTable, sizeof(CPU_MICROCODE_EXTENDED_TABLE));
 147                 if (CheckSum32 == 0) {
 148                   //
 149                   // Verify Header
 150                   //
 151                   if ((ExtendedTable->ProcessorSignature.Uint32 == Eax.Uint32) &&
 152                       (ExtendedTable->ProcessorFlag & (1 << PlatformId)) ) {
 153                     //
 154                     // Find one
 155                     //
 156                     CorrectMicrocode = TRUE;
 157                     break;
 158                   }
 159                 }
 160                 ExtendedTable ++;
 161               }
 162             }
 163           }
 164         }
 165       }
 166     } else {
 167       //
 168       // It is the padding data between the microcode patches for microcode patches alignment.
 169       // Because the microcode patch is the multiple of 1-KByte, the padding data should not
 170       // exist if the microcode patch alignment value is not larger than 1-KByte. So, the microcode
 171       // alignment value should be larger than 1-KByte. We could skip SIZE_1KB padding data to
 172       // find the next possible microcode patch header.
 173       //
 174       MicrocodeEntryPoint = (CPU_MICROCODE_HEADER *) (((UINTN) MicrocodeEntryPoint) + SIZE_1KB);
 175       continue;
 176     }
 177     //
 178     // Get the next patch.
 179     //
 180     if (MicrocodeEntryPoint->DataSize == 0) {
 181       TotalSize = 2048;
 182     } else {
 183       TotalSize = MicrocodeEntryPoint->TotalSize;
 184     }
 185
 186     if (CorrectMicrocode) {
 187       LatestRevision = MicrocodeEntryPoint->UpdateRevision;
 188       MicrocodeData = (VOID *) ((UINTN) MicrocodeEntryPoint + sizeof (CPU_MICROCODE_HEADER));
 189     }
 190
 191     MicrocodeEntryPoint = (CPU_MICROCODE_HEADER *) (((UINTN) MicrocodeEntryPoint) + TotalSize);
 192   } while (((UINTN) MicrocodeEntryPoint < MicrocodeEnd));
 193
 194   if (LatestRevision > CurrentRevision) {
 195     //
 196     // BIOS only authenticate updates that contain a numerically larger revision
 197     // than the currently loaded revision, where Current Signature < New Update
 198     // Revision. A processor with no loaded update is considered to have a
 199     // revision equal to zero.
 200     //
 201     AsmWriteMsr64 (
 202         MSR_IA32_BIOS_UPDT_TRIG,
 203         (UINT64) (UINTN) MicrocodeData
 204         );
 205     //
 206     // Get and check new microcode signature
 207     //
 208     CurrentRevision = GetCurrentMicrocodeSignature ();
 209     if (CurrentRevision != LatestRevision) {
 210       AcquireSpinLock(&CpuMpData->MpLock);
 211       DEBUG ((EFI_D_ERROR, "Updated microcode signature [0x%08x] does not match \
 212                 loaded microcode signature [0x%08x]\n", CurrentRevision, LatestRevision));
 213       ReleaseSpinLock(&CpuMpData->MpLock);
 214     }
 215   }
 216 }