35-144 Vol. 3C
MODEL-SPECIFIC REGISTERS (MSRS)
CEH
206
MSR_PLATFORM_INFO
Package
See http://biosbits.org.
7:0
Reserved.
15:8
Package
Maximum Non-Turbo Ratio (R/O)
The is the ratio of the frequency that invariant TSC runs at.
Frequency = ratio * 100 MHz.
27:16
Reserved.
28
Package
Programmable Ratio Limit for Turbo Mode (R/O)
When set to 1, indicates that Programmable Ratio Limits for Turbo
mode is enabled, and when set to 0, indicates Programmable Ratio
Limits for Turbo mode is disabled.
29
Package
Programmable TDP Limit for Turbo Mode (R/O)
When set to 1, indicates that TDP Limits for Turbo mode are
programmable, and when set to 0, indicates TDP Limit for Turbo
mode is not programmable.
39:30
Reserved.
47:40
Package
Maximum Efficiency Ratio (R/O)
The is the minimum ratio (maximum efficiency) that the processor
can operates, in units of 100MHz.
63:48
Reserved.
E2H
226
MSR_PKG_CST_CONFIG_
CONTROL
Core
C-State Configuration Control (R/W)
Note: C-state values are processor specific C-state code names,
unrelated to MWAIT extension C-state parameters or ACPI C-
States.
See http://biosbits.org.
2:0
Package C-State Limit (R/W)
Specifies the lowest processor-specific C-state code name
(consuming the least power). for the package. The default is set as
factory-configured package C-state limit.
The following C-state code name encodings are supported:
000b: C0/C1 (no package C-sate support)
001b: C2
010b: C6 no retention
011b: C6 retention
100b: C7
101b: C7s
111: No package C-state limit.
Note: This field cannot be used to limit package C-state to C3.
9:3
Reserved.
10
I/O MWAIT Redirection Enable (R/W)
When set, will map IO_read instructions sent to IO register
specified by MSR_PMG_IO_CAPTURE_BASE to MWAIT instructions
14:11
Reserved.
Table 35-18. MSRs Supported by IntelĀ® Processors
based on IntelĀ® microarchitecture code name Sandy Bridge (Contd.)
Register
Address
Register Name
Scope
Bit Description
Hex
Dec