2 Implementation of loading microcode on processors.
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
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.
18 Get microcode update signature of currently loaded microcode update.
20 @return Microcode signature.
23 GetCurrentMicrocodeSignature (
27 MSR_IA32_BIOS_SIGN_ID_REGISTER BiosSignIdMsr
;
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
;
36 Detect whether specified processor can find matching microcode patch and load it.
38 @param[in] CpuMpData The pointer to CPU MP Data structure.
42 IN CPU_MP_DATA
*CpuMpData
45 UINT32 ExtendedTableLength
;
46 UINT32 ExtendedTableCount
;
47 CPU_MICROCODE_EXTENDED_TABLE
*ExtendedTable
;
48 CPU_MICROCODE_EXTENDED_TABLE_HEADER
*ExtendedTableHeader
;
49 CPU_MICROCODE_HEADER
*MicrocodeEntryPoint
;
53 CPUID_VERSION_INFO_EAX Eax
;
54 UINT32 CurrentRevision
;
55 UINT32 LatestRevision
;
58 BOOLEAN CorrectMicrocode
;
60 MSR_IA32_PLATFORM_ID_REGISTER PlatformIdMsr
;
62 if (CpuMpData
->MicrocodePatchRegionSize
== 0) {
64 // There is no microcode patches
69 CurrentRevision
= GetCurrentMicrocodeSignature ();
70 if (CurrentRevision
!= 0) {
72 // Skip loading microcode if it has been loaded successfully
77 ExtendedTableLength
= 0;
79 // Here data of CPUID leafs have not been collected into context buffer, so
80 // GetProcessorCpuid() cannot be used here to retrieve sCPUID data.
82 AsmCpuid (CPUID_VERSION_INFO
, &Eax
.Uint32
, NULL
, NULL
, NULL
);
85 // The index of platform information resides in bits 50:52 of MSR IA32_PLATFORM_ID
87 PlatformIdMsr
.Uint64
= AsmReadMsr64 (MSR_IA32_PLATFORM_ID
);
88 PlatformId
= (UINT8
) PlatformIdMsr
.Bits
.PlatformId
;
92 MicrocodeEnd
= (UINTN
) (CpuMpData
->MicrocodePatchAddress
+ CpuMpData
->MicrocodePatchRegionSize
);
93 MicrocodeEntryPoint
= (CPU_MICROCODE_HEADER
*) (UINTN
) CpuMpData
->MicrocodePatchAddress
;
96 // Check if the microcode is for the Cpu and the version is newer
97 // and the update can be processed on the platform
99 CorrectMicrocode
= FALSE
;
100 if (MicrocodeEntryPoint
->HeaderVersion
== 0x1) {
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....).
106 if (MicrocodeEntryPoint
->ProcessorSignature
.Uint32
== Eax
.Uint32
&&
107 MicrocodeEntryPoint
->UpdateRevision
> LatestRevision
&&
108 (MicrocodeEntryPoint
->ProcessorFlags
& (1 << PlatformId
))
110 if (MicrocodeEntryPoint
->DataSize
== 0) {
111 CheckSum32
= CalculateSum32 ((UINT32
*) MicrocodeEntryPoint
, 2048);
113 CheckSum32
= CalculateSum32 (
114 (UINT32
*) MicrocodeEntryPoint
,
115 MicrocodeEntryPoint
->DataSize
+ sizeof (CPU_MICROCODE_HEADER
)
118 if (CheckSum32
== 0) {
119 CorrectMicrocode
= TRUE
;
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) {
127 // Extended Table exist, check if the CPU in support list
129 ExtendedTableHeader
= (CPU_MICROCODE_EXTENDED_TABLE_HEADER
*) ((UINT8
*) (MicrocodeEntryPoint
)
130 + MicrocodeEntryPoint
->DataSize
+ sizeof (CPU_MICROCODE_HEADER
));
132 // Calculate Extended Checksum
134 if ((ExtendedTableLength
% 4) == 0) {
135 CheckSum32
= CalculateSum32 ((UINT32
*) ExtendedTableHeader
, ExtendedTableLength
);
136 if (CheckSum32
== 0) {
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) {
148 if ((ExtendedTable
->ProcessorSignature
.Uint32
== Eax
.Uint32
) &&
149 (ExtendedTable
->ProcessorFlag
& (1 << PlatformId
)) ) {
153 CorrectMicrocode
= TRUE
;
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.
171 MicrocodeEntryPoint
= (CPU_MICROCODE_HEADER
*) (((UINTN
) MicrocodeEntryPoint
) + SIZE_1KB
);
175 // Get the next patch.
177 if (MicrocodeEntryPoint
->DataSize
== 0) {
180 TotalSize
= MicrocodeEntryPoint
->TotalSize
;
183 if (CorrectMicrocode
) {
184 LatestRevision
= MicrocodeEntryPoint
->UpdateRevision
;
185 MicrocodeData
= (VOID
*) ((UINTN
) MicrocodeEntryPoint
+ sizeof (CPU_MICROCODE_HEADER
));
188 MicrocodeEntryPoint
= (CPU_MICROCODE_HEADER
*) (((UINTN
) MicrocodeEntryPoint
) + TotalSize
);
189 } while (((UINTN
) MicrocodeEntryPoint
< MicrocodeEnd
));
191 if (LatestRevision
> CurrentRevision
) {
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.
198 ASSERT (MicrocodeData
!= NULL
);
200 MSR_IA32_BIOS_UPDT_TRIG
,
201 (UINT64
) (UINTN
) MicrocodeData
204 // Get and check new microcode signature
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
);