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   do {
 163     //
 164     // Check if the microcode is for the Cpu and the version is newer
 165     // and the update can be processed on the platform
 166     //
 167     CorrectMicrocode = FALSE;
 168
 169     //
 170     // Save an in-complete CheckSum32 from CheckSum Part1 for common parts.
 171     //
 172     if (MicrocodeEntryPoint->DataSize == 0) {
 173       InCompleteCheckSum32 = CalculateSum32 (
 174                                (UINT32 *) MicrocodeEntryPoint,
 175                                sizeof (CPU_MICROCODE_HEADER) + 2000
 176                                );
 177     } else {
 178       InCompleteCheckSum32 = CalculateSum32 (
 179                                (UINT32 *) MicrocodeEntryPoint,
 180                                sizeof (CPU_MICROCODE_HEADER) + MicrocodeEntryPoint->DataSize
 181                                );
 182     }
 183     InCompleteCheckSum32 -= MicrocodeEntryPoint->ProcessorSignature.Uint32;
 184     InCompleteCheckSum32 -= MicrocodeEntryPoint->ProcessorFlags;
 185     InCompleteCheckSum32 -= MicrocodeEntryPoint->Checksum;
 186
 187     if (MicrocodeEntryPoint->HeaderVersion == 0x1) {
 188       //
 189       // It is the microcode header. It is not the padding data between microcode patches
 190       // because the padding data should not include 0x00000001 and it should be the repeated
 191       // byte format (like 0xXYXYXYXY....).
 192       //
 193       if (MicrocodeEntryPoint->ProcessorSignature.Uint32 == Eax.Uint32 &&
 194           MicrocodeEntryPoint->UpdateRevision > LatestRevision &&
 195           (MicrocodeEntryPoint->ProcessorFlags & (1 << PlatformId))
 196           ) {
 197         //
 198         // Calculate CheckSum Part1.
 199         //
 200         CheckSum32 = InCompleteCheckSum32;
 201         CheckSum32 += MicrocodeEntryPoint->ProcessorSignature.Uint32;
 202         CheckSum32 += MicrocodeEntryPoint->ProcessorFlags;
 203         CheckSum32 += MicrocodeEntryPoint->Checksum;
 204         if (CheckSum32 == 0) {
 205           CorrectMicrocode = TRUE;
 206           ProcessorFlags = MicrocodeEntryPoint->ProcessorFlags;
 207         }
 208       } else if ((MicrocodeEntryPoint->DataSize != 0) &&
 209                  (MicrocodeEntryPoint->UpdateRevision > LatestRevision)) {
 210         ExtendedTableLength = MicrocodeEntryPoint->TotalSize - (MicrocodeEntryPoint->DataSize +
 211                                 sizeof (CPU_MICROCODE_HEADER));
 212         if (ExtendedTableLength != 0) {
 213           //
 214           // Extended Table exist, check if the CPU in support list
 215           //
 216           ExtendedTableHeader = (CPU_MICROCODE_EXTENDED_TABLE_HEADER *) ((UINT8 *) (MicrocodeEntryPoint)
 217                                   + MicrocodeEntryPoint->DataSize + sizeof (CPU_MICROCODE_HEADER));
 218           //
 219           // Calculate Extended Checksum
 220           //
 221           if ((ExtendedTableLength % 4) == 0) {
 222             //
 223             // Calculate CheckSum Part2.
 224             //
 225             CheckSum32 = CalculateSum32 ((UINT32 *) ExtendedTableHeader, ExtendedTableLength);
 226             if (CheckSum32 == 0) {
 227               //
 228               // Checksum correct
 229               //
 230               ExtendedTableCount = ExtendedTableHeader->ExtendedSignatureCount;
 231               ExtendedTable      = (CPU_MICROCODE_EXTENDED_TABLE *) (ExtendedTableHeader + 1);
 232               for (Index = 0; Index < ExtendedTableCount; Index ++) {
 233                 //
 234                 // Calculate CheckSum Part3.
 235                 //
 236                 CheckSum32 = InCompleteCheckSum32;
 237                 CheckSum32 += ExtendedTable->ProcessorSignature.Uint32;
 238                 CheckSum32 += ExtendedTable->ProcessorFlag;
 239                 CheckSum32 += ExtendedTable->Checksum;
 240                 if (CheckSum32 == 0) {
 241                   //
 242                   // Verify Header
 243                   //
 244                   if ((ExtendedTable->ProcessorSignature.Uint32 == Eax.Uint32) &&
 245                       (ExtendedTable->ProcessorFlag & (1 << PlatformId)) ) {
 246                     //
 247                     // Find one
 248                     //
 249                     CorrectMicrocode = TRUE;
 250                     ProcessorFlags = ExtendedTable->ProcessorFlag;
 251                     break;
 252                   }
 253                 }
 254                 ExtendedTable ++;
 255               }
 256             }
 257           }
 258         }
 259       }
 260     } else {
 261       //
 262       // It is the padding data between the microcode patches for microcode patches alignment.
 263       // Because the microcode patch is the multiple of 1-KByte, the padding data should not
 264       // exist if the microcode patch alignment value is not larger than 1-KByte. So, the microcode
 265       // alignment value should be larger than 1-KByte. We could skip SIZE_1KB padding data to
 266       // find the next possible microcode patch header.
 267       //
 268       MicrocodeEntryPoint = (CPU_MICROCODE_HEADER *) (((UINTN) MicrocodeEntryPoint) + SIZE_1KB);
 269       continue;
 270     }
 271     //
 272     // Get the next patch.
 273     //
 274     if (MicrocodeEntryPoint->DataSize == 0) {
 275       TotalSize = 2048;
 276     } else {
 277       TotalSize = MicrocodeEntryPoint->TotalSize;
 278     }
 279
 280     if (CorrectMicrocode) {
 281       LatestRevision = MicrocodeEntryPoint->UpdateRevision;
 282       MicrocodeData = (VOID *) ((UINTN) MicrocodeEntryPoint + sizeof (CPU_MICROCODE_HEADER));
 283     }
 284
 285     MicrocodeEntryPoint = (CPU_MICROCODE_HEADER *) (((UINTN) MicrocodeEntryPoint) + TotalSize);
 286   } while (((UINTN) MicrocodeEntryPoint < MicrocodeEnd));
 287
 288 Done:
 289   if (LatestRevision > CurrentRevision) {
 290     //
 291     // BIOS only authenticate updates that contain a numerically larger revision
 292     // than the currently loaded revision, where Current Signature < New Update
 293     // Revision. A processor with no loaded update is considered to have a
 294     // revision equal to zero.
 295     //
 296     ASSERT (MicrocodeData != NULL);
 297     AsmWriteMsr64 (
 298         MSR_IA32_BIOS_UPDT_TRIG,
 299         (UINT64) (UINTN) MicrocodeData
 300         );
 301     //
 302     // Get and check new microcode signature
 303     //
 304     CurrentRevision = GetCurrentMicrocodeSignature ();
 305     if (CurrentRevision != LatestRevision) {
 306       AcquireSpinLock(&CpuMpData->MpLock);
 307       DEBUG ((EFI_D_ERROR, "Updated microcode signature [0x%08x] does not match \
 308                 loaded microcode signature [0x%08x]\n", CurrentRevision, LatestRevision));
 309       ReleaseSpinLock(&CpuMpData->MpLock);
 310     }
 311   }
 312
 313   if (IsBspCallIn && (LatestRevision != 0)) {
 314     //
 315     // Save BSP processor info and microcode info for later AP use.
 316     //
 317     CpuMpData->ProcessorSignature   = Eax.Uint32;
 318     CpuMpData->ProcessorFlags       = ProcessorFlags;
 319     CpuMpData->MicrocodeDataAddress = (UINTN) MicrocodeData;
 320     CpuMpData->MicrocodeRevision    = LatestRevision;
 321     DEBUG ((DEBUG_INFO, "BSP Microcode:: signature [0x%08x], ProcessorFlags [0x%08x], \
 322        MicroData [0x%08x], Revision [0x%08x]\n", Eax.Uint32, ProcessorFlags, (UINTN) MicrocodeData, LatestRevision));
 323   }
 324 }