Method and apparatus to configure thermal design power in a microprocessor
A technique to change a thermal design power (TDP) value. In one embodiment, one or more environmental or user-driven changes may cause a processor's TDP value to be changed. Furthermore, in some embodiments a change in TDP may alter a turbo mode target frequency.
1. A processor comprising:
a plurality of cores;
an integrated memory controller to communicatively couple the cores to a system memory;
first circuitry to set a thermal design power (TDP) setting in a Basic Input/Output System (BIOS) based on a user selection in a user interface for the processor and to change a configurable power limit value for the processor based on the TDP setting, wherein the configurable power limit value is to limit a power consumption of the processor,
second circuitry to read the configurable power limit value and write, in a register of a first core, power state information associated with the configurable power limit value, the power state information including a maximum power state for the first core and indicating one of a plurality of power states in which the first core is to currently operate,
wherein the plurality of power states includes at least one low power state and at least one turbo mode state;
a level one cache integral to each one of the plurality of cores;
a first shared cache shared by two or more of the plurality of cores; and
an inter-processor interconnect to communicatively couple the plurality of cores to cores of one or more other processors.
2. The processor of claim 1 , wherein the power state information is associated with one of a plurality of Advanced Configuration and Power Interface (ACPI) power states.
3. The processor of claim 1 , wherein each of the plurality of power states maps to a distinct frequency to operate one core.
4. The processor of claim 3 , wherein mapped frequencies comprise a plurality of frequencies that have an integer number of an offset frequency from a base frequency.