Техническая Спецификация для Intel C2338 FH8065501516761
Модели
FH8065501516761
Intel
®
Atom™ Processor C2000 Product Family for Microserver
September 2014
Datasheet, Vol. 2 of 3
Order Number: 330061-002US
159
Volume 2—Power Management—C2000 Product Family
Active State Power Management Overview
9.7
Active State Power Management Overview
When one or more of the processor cores are active, the SoC power management
adjusts the operating conditions as needed to reflect both the objectives of the
operating system and the physical temperature and power-related constraints. In most
cases, objectives are met by adjusting the target frequency of each active core. The
SoC power management adjusts each core target clock speed to a discrete operating
point. The discrete steps between these operating points correspond to core clock
ratios.
As the target frequency is changed, the operating voltage is set to the highest sVID
request from all modules. Several factors contribute to the active operating point of a
core at any given instant:
• Operating System (OS) P-State requests for that core
• P-State requests of the other cores in the package
• The P-State selection model
• The current temperature of each core
• Any available turbo modes
• Previous P-states and C-states
• Any other factors
• P-State requests of the other cores in the package
• The P-State selection model
• The current temperature of each core
• Any available turbo modes
• Previous P-states and C-states
• Any other factors
Based on a snapshot of these factors, the SoC determines a target ratio and associated
frequency for each core as well as a package target. The resolved package operating
point is the highest requested operating point of any of the cores in the package, after
all factors are taken into account.
When the core is idle (in a lower-power C-State than C0), its voting rights may be
suspended based on the Energy Performance BIAS MSR setting (0x1b0), and the core
either acts as a slave to the operating voltage specified by other cores or has its
voltage removed by turning off its power gate.
When resolving the operating point of an individual core, the various contributing
factors are weighed independently to come up with three ratio targets:
• Software-initiated request (OS P-State request),
• Thermally-constrained operating target, and
• Power-constrained operating target.
• Thermally-constrained operating target, and
• Power-constrained operating target.
The upper and lower bounds of these targets are weighed and prioritized to come up
with a final ratio resolution for each core and the sections.
Additional active-state power management features change the power processor core
characteristics without changing the operating voltage and frequency. For the most
part, these features provide legacy power management functionality, and are
superseded by the newer voltage and frequency scaling capabilities of today’s
processors.