UefiCpuPkg/Library/MpInitLib/Microcode.c

   1 /** @file
   2   Implementation of loading microcode on processors.
   3
   4   Copyright (c) 2015 - 2018, 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   Microcode Payload as the following format:
  39   +----------------------------------------+------------------+
  40   |          CPU_MICROCODE_HEADER          |                  |
  41   +----------------------------------------+  CheckSum Part1  |
  42   |            Microcode Binary            |                  |
  43   +----------------------------------------+------------------+
  44   |  CPU_MICROCODE_EXTENDED_TABLE_HEADER   |                  |
  45   +----------------------------------------+  CheckSum Part2  |
  46   |      CPU_MICROCODE_EXTENDED_TABLE      |                  |
  47   |                   ...                  |                  |
  48   +----------------------------------------+------------------+
  49
  50   There may by multiple CPU_MICROCODE_EXTENDED_TABLE in this format.
  51   The count of CPU_MICROCODE_EXTENDED_TABLE is indicated by ExtendedSignatureCount
  52   of CPU_MICROCODE_EXTENDED_TABLE_HEADER structure.
  53
  54   When we are trying to verify the CheckSum32 with extended table.
  55   We should use the fields of exnteded table to replace the corresponding
  56   fields in CPU_MICROCODE_HEADER structure, and recalculate the
  57   CheckSum32 with CPU_MICROCODE_HEADER + Microcode Binary. We named
  58   it as CheckSum Part3.
  59
  60   The CheckSum Part2 is used to verify the CPU_MICROCODE_EXTENDED_TABLE_HEADER
  61   and CPU_MICROCODE_EXTENDED_TABLE parts. We should make sure CheckSum Part2
  62   is correct before we are going to verify each CPU_MICROCODE_EXTENDED_TABLE.
  63
  64   Only ProcessorSignature, ProcessorFlag and CheckSum are different between
  65   CheckSum Part1 and CheckSum Part3. To avoid multiple computing CheckSum Part3.
  66   Save an in-complete CheckSum32 from CheckSum Part1 for common parts.
  67   When we are going to calculate CheckSum32, just should use the corresponding part
  68   of the ProcessorSignature, ProcessorFlag and CheckSum with in-complete CheckSum32.
  69
  70   Notes: CheckSum32 is not a strong verification.
  71          It does not guarantee that the data has not been modified.
  72          CPU has its own mechanism to verify Microcode Binary part.
  73
  74   @param[in]  CpuMpData    The pointer to CPU MP Data structure.
  75   @param[in]  IsBspCallIn  Indicate whether the caller is BSP or not.
  76 **/
  77 VOID
  78 MicrocodeDetect (
  79   IN CPU_MP_DATA             *CpuMpData,
  80   IN BOOLEAN                 IsBspCallIn
  81   )
  82 {
  83   UINT32                                  ExtendedTableLength;
  84   UINT32                                  ExtendedTableCount;
  85   CPU_MICROCODE_EXTENDED_TABLE            *ExtendedTable;
  86   CPU_MICROCODE_EXTENDED_TABLE_HEADER     *ExtendedTableHeader;
  87   CPU_MICROCODE_HEADER                    *MicrocodeEntryPoint;
  88   UINTN                                   MicrocodeEnd;
  89   UINTN                                   Index;
  90   UINT8                                   PlatformId;
  91   CPUID_VERSION_INFO_EAX                  Eax;
  92   UINT32                                  CurrentRevision;
  93   UINT32                                  LatestRevision;
  94   UINTN                                   TotalSize;
  95   UINT32                                  CheckSum32;
  96   UINT32                                  InCompleteCheckSum32;
  97   BOOLEAN                                 CorrectMicrocode;
  98   VOID                                    *MicrocodeData;
  99   MSR_IA32_PLATFORM_ID_REGISTER           PlatformIdMsr;
 100   UINT32                                  ProcessorFlags;
 101   UINT32                                  ThreadId;
 102
 103   //
 104   // set ProcessorFlags to suppress incorrect compiler/analyzer warnings
 105   //
 106   ProcessorFlags = 0;
 107
 108   if (CpuMpData->MicrocodePatchRegionSize == 0) {
 109     //
 110     // There is no microcode patches
 111     //
 112     return;
 113   }
 114
 115   CurrentRevision = GetCurrentMicrocodeSignature ();
 116   if (CurrentRevision != 0 && !IsBspCallIn) {
 117     //
 118     // Skip loading microcode if it has been loaded successfully
 119     //
 120     return;
 121   }
 122
 123   GetProcessorLocationByApicId (GetInitialApicId (), NULL, NULL, &ThreadId);
 124   if (ThreadId != 0) {
 125     //
 126     // Skip loading microcode if it is not the first thread in one core.
 127     //
 128     return;
 129   }
 130
 131   ExtendedTableLength = 0;
 132   //
 133   // Here data of CPUID leafs have not been collected into context buffer, so
 134   // GetProcessorCpuid() cannot be used here to retrieve CPUID data.
 135   //
 136   AsmCpuid (CPUID_VERSION_INFO, &Eax.Uint32, NULL, NULL, NULL);
 137
 138   //
 139   // The index of platform information resides in bits 50:52 of MSR IA32_PLATFORM_ID
 140   //
 141   PlatformIdMsr.Uint64 = AsmReadMsr64 (MSR_IA32_PLATFORM_ID);
 142   PlatformId = (UINT8) PlatformIdMsr.Bits.PlatformId;
 143
 144   //
 145   // Check whether AP has same processor with BSP.
 146   // If yes, direct use microcode info saved by BSP.
 147   //
 148   if (!IsBspCallIn) {
 149     if ((CpuMpData->ProcessorSignature == Eax.Uint32) &&
 150         (CpuMpData->ProcessorFlags & (1 << PlatformId)) != 0) {
 151         MicrocodeData = (VOID *)(UINTN) CpuMpData->MicrocodeDataAddress;
 152         LatestRevision = CpuMpData->MicrocodeRevision;
 153         goto Done;
 154     }
 155   }
 156
 157   LatestRevision = 0;
 158   MicrocodeData  = NULL;
 159   MicrocodeEnd = (UINTN) (CpuMpData->MicrocodePatchAddress + CpuMpData->MicrocodePatchRegionSize);
 160   MicrocodeEntryPoint = (CPU_MICROCODE_HEADER *) (UINTN) CpuMpData->MicrocodePatchAddress;
 161
 162   //
 163   // Save an in-complete CheckSum32 from CheckSum Part1 for common parts.
 164   //
 165   if (MicrocodeEntryPoint->DataSize == 0) {
 166     InCompleteCheckSum32 = CalculateSum32 (
 167                              (UINT32 *) MicrocodeEntryPoint,
 168                              sizeof (CPU_MICROCODE_HEADER) + 2000
 169                              );
 170   } else {
 171     InCompleteCheckSum32 = CalculateSum32 (
 172                              (UINT32 *) MicrocodeEntryPoint,
 173                              sizeof (CPU_MICROCODE_HEADER) + MicrocodeEntryPoint->DataSize
 174                              );
 175   }
 176   InCompleteCheckSum32 -= MicrocodeEntryPoint->ProcessorSignature.Uint32;
 177   InCompleteCheckSum32 -= MicrocodeEntryPoint->ProcessorFlags;
 178   InCompleteCheckSum32 -= MicrocodeEntryPoint->Checksum;
 179
 180   do {
 181     //
 182     // Check if the microcode is for the Cpu and the version is newer
 183     // and the update can be processed on the platform
 184     //
 185     CorrectMicrocode = FALSE;
 186     if (MicrocodeEntryPoint->HeaderVersion == 0x1) {
 187       //
 188       // It is the microcode header. It is not the padding data between microcode patches
 189       // because the padding data should not include 0x00000001 and it should be the repeated
 190       // byte format (like 0xXYXYXYXY....).
 191       //
 192       if (MicrocodeEntryPoint->ProcessorSignature.Uint32 == Eax.Uint32 &&
 193           MicrocodeEntryPoint->UpdateRevision > LatestRevision &&
 194           (MicrocodeEntryPoint->ProcessorFlags & (1 << PlatformId))
 195           ) {
 196         //
 197         // Calculate CheckSum Part1.
 198         //
 199         CheckSum32 = InCompleteCheckSum32;
 200         CheckSum32 += MicrocodeEntryPoint->ProcessorSignature.Uint32;
 201         CheckSum32 += MicrocodeEntryPoint->ProcessorFlags;
 202         CheckSum32 += MicrocodeEntryPoint->Checksum;
 203         if (CheckSum32 == 0) {
 204           CorrectMicrocode = TRUE;
 205           ProcessorFlags = MicrocodeEntryPoint->ProcessorFlags;
 206         }
 207       } else if ((MicrocodeEntryPoint->DataSize != 0) &&
 208                  (MicrocodeEntryPoint->UpdateRevision > LatestRevision)) {
 209         ExtendedTableLength = MicrocodeEntryPoint->TotalSize - (MicrocodeEntryPoint->DataSize +
 210                                 sizeof (CPU_MICROCODE_HEADER));
 211         if (ExtendedTableLength != 0) {
 212           //
 213           // Extended Table exist, check if the CPU in support list
 214           //
 215           ExtendedTableHeader = (CPU_MICROCODE_EXTENDED_TABLE_HEADER *) ((UINT8 *) (MicrocodeEntryPoint)
 216                                   + MicrocodeEntryPoint->DataSize + sizeof (CPU_MICROCODE_HEADER));
 217           //
 218           // Calculate Extended Checksum
 219           //
 220           if ((ExtendedTableLength % 4) == 0) {
 221             //
 222             // Calculate CheckSum Part2.
 223             //
 224             CheckSum32 = CalculateSum32 ((UINT32 *) ExtendedTableHeader, ExtendedTableLength);
 225             if (CheckSum32 == 0) {
 226               //
 227               // Checksum correct
 228               //
 229               ExtendedTableCount = ExtendedTableHeader->ExtendedSignatureCount;
 230               ExtendedTable      = (CPU_MICROCODE_EXTENDED_TABLE *) (ExtendedTableHeader + 1);
 231               for (Index = 0; Index < ExtendedTableCount; Index ++) {
 232                 //
 233                 // Calculate CheckSum Part3.
 234                 //
 235                 CheckSum32 = InCompleteCheckSum32;
 236                 CheckSum32 += ExtendedTable->ProcessorSignature.Uint32;
 237                 CheckSum32 += ExtendedTable->ProcessorFlag;
 238                 CheckSum32 += ExtendedTable->Checksum;
 239                 if (CheckSum32 == 0) {
 240                   //
 241                   // Verify Header
 242                   //
 243                   if ((ExtendedTable->ProcessorSignature.Uint32 == Eax.Uint32) &&
 244                       (ExtendedTable->ProcessorFlag & (1 << PlatformId)) ) {
 245                     //
 246                     // Find one
 247                     //
 248                     CorrectMicrocode = TRUE;
 249                     ProcessorFlags = ExtendedTable->ProcessorFlag;
 250                     break;
 251                   }
 252                 }
 253                 ExtendedTable ++;
 254               }
 255             }
 256           }
 257         }
 258       }
 259     } else {
 260       //
 261       // It is the padding data between the microcode patches for microcode patches alignment.
 262       // Because the microcode patch is the multiple of 1-KByte, the padding data should not
 263       // exist if the microcode patch alignment value is not larger than 1-KByte. So, the microcode
 264       // alignment value should be larger than 1-KByte. We could skip SIZE_1KB padding data to
 265       // find the next possible microcode patch header.
 266       //
 267       MicrocodeEntryPoint = (CPU_MICROCODE_HEADER *) (((UINTN) MicrocodeEntryPoint) + SIZE_1KB);
 268       continue;
 269     }
 270     //
 271     // Get the next patch.
 272     //
 273     if (MicrocodeEntryPoint->DataSize == 0) {
 274       TotalSize = 2048;
 275     } else {
 276       TotalSize = MicrocodeEntryPoint->TotalSize;
 277     }
 278
 279     if (CorrectMicrocode) {
 280       LatestRevision = MicrocodeEntryPoint->UpdateRevision;
 281       MicrocodeData = (VOID *) ((UINTN) MicrocodeEntryPoint + sizeof (CPU_MICROCODE_HEADER));
 282     }
 283
 284     MicrocodeEntryPoint = (CPU_MICROCODE_HEADER *) (((UINTN) MicrocodeEntryPoint) + TotalSize);
 285   } while (((UINTN) MicrocodeEntryPoint < MicrocodeEnd));
 286
 287 Done:
 288   if (LatestRevision > CurrentRevision) {
 289     //
 290     // BIOS only authenticate updates that contain a numerically larger revision
 291     // than the currently loaded revision, where Current Signature < New Update
 292     // Revision. A processor with no loaded update is considered to have a
 293     // revision equal to zero.
 294     //
 295     ASSERT (MicrocodeData != NULL);
 296     AsmWriteMsr64 (
 297         MSR_IA32_BIOS_UPDT_TRIG,
 298         (UINT64) (UINTN) MicrocodeData
 299         );
 300     //
 301     // Get and check new microcode signature
 302     //
 303     CurrentRevision = GetCurrentMicrocodeSignature ();
 304     if (CurrentRevision != LatestRevision) {
 305       AcquireSpinLock(&CpuMpData->MpLock);
 306       DEBUG ((EFI_D_ERROR, "Updated microcode signature [0x%08x] does not match \
 307                 loaded microcode signature [0x%08x]\n", CurrentRevision, LatestRevision));
 308       ReleaseSpinLock(&CpuMpData->MpLock);
 309     }
 310   }
 311
 312   if (IsBspCallIn && (LatestRevision != 0)) {
 313     //
 314     // Save BSP processor info and microcode info for later AP use.
 315     //
 316     CpuMpData->ProcessorSignature   = Eax.Uint32;
 317     CpuMpData->ProcessorFlags       = ProcessorFlags;
 318     CpuMpData->MicrocodeDataAddress = (UINTN) MicrocodeData;
 319     CpuMpData->MicrocodeRevision    = LatestRevision;
 320     DEBUG ((DEBUG_INFO, "BSP Microcode:: signature [0x%08x], ProcessorFlags [0x%08x], \
 321        MicroData [0x%08x], Revision [0x%08x]\n", Eax.Uint32, ProcessorFlags, (UINTN) MicrocodeData, LatestRevision));
 322   }
 323 }