Vol. 3C 35-141

MODEL-SPECIFIC REGISTERS (MSRS)

35.8 

MSRS IN THE INTEL

®

 XEON

®

 PROCESSOR E7 FAMILY (BASED ON INTEL

®

 

MICROARCHITECTURE CODE NAME WESTMERE)

Intel

®

 Xeon

®

 Processor E7 Family (based on Intel

®

 microarchitecture code name Westmere) supports the MSR 

interfaces listed in Table 35-13 (except MSR address 1ADH), Table 35-14, plus additional MSR listed in Table 35-17. 
These processors have a CPUID signature with DisplayFamily_DisplayModel of 06_2FH.

Table 35-17.  Additional MSRs Supported by Intel® Xeon® Processor E7 Family

Register 

Address

Register Name

Scope

Bit Description

 Hex

Dec

13CH

52

MSR_FEATURE_CONFIG

Core

AES Configuration (RW-L)
Privileged post-BIOS agent must provide a #GP handler to handle 

unsuccessful read of this MSR.

1:0

AES Configuration (RW-L) 
Upon a successful read of this MSR, the configuration of AES 

instruction set availability is as follows:
11b: AES instructions are not available until next RESET.
otherwise, AES instructions are available.
Note, AES instruction set is not available if read is unsuccessful. If 

the configuration is not 01b, AES instruction can be mis-configured 

if a privileged agent unintentionally writes 11b.

63:2

Reserved.

1A7H

423

MSR_OFFCORE_RSP_1

Thread

Offcore Response Event Select Register (R/W)

1ADH

429

MSR_TURBO_RATIO_LIMIT

Package

Reserved
Attempt to read/write will cause #UD.

1B0H

432

IA32_ENERGY_PERF_BIAS

Package

See Table 35-2.

F40H

3904

MSR_C8_PMON_BOX_CTRL Package

Uncore C-box 8 perfmon local box control MSR.

F41H

3905

MSR_C8_PMON_BOX_

STATUS

Package

Uncore C-box 8 perfmon local box status MSR.

F42H

3906

MSR_C8_PMON_BOX_OVF_

CTRL

Package

Uncore C-box 8 perfmon local box overflow control MSR.

F50H

3920

MSR_C8_PMON_EVNT_

SEL0

Package

Uncore C-box 8 perfmon event select MSR.

F51H

3921

MSR_C8_PMON_CTR0

Package

Uncore C-box 8 perfmon counter MSR.

F52H

3922

MSR_C8_PMON_EVNT_

SEL1

Package

Uncore C-box 8 perfmon event select MSR.

F53H

3923

MSR_C8_PMON_CTR1

Package

Uncore C-box 8 perfmon counter MSR.

F54H

3924

MSR_C8_PMON_EVNT_

SEL2

Package

Uncore C-box 8 perfmon event select MSR.

F55H

3925

MSR_C8_PMON_CTR2

Package

Uncore C-box 8 perfmon counter MSR.

F56H

3926

MSR_C8_PMON_EVNT_

SEL3

Package

Uncore C-box 8 perfmon event select MSR.

F57H

3927

MSR_C8_PMON_CTR3

Package

Uncore C-box 8 perfmon counter MSR.