Graphics processor sub-domain voltage regulation

A processing system, comprising:

• a central processor core;
• a graphics processor core;
• and
• a first voltage regulator to provide power supply rails to both the central processor core and graphics processor core, wherein the graphics processor core further comprises:
• a first voltage domain coupled to receive a domain voltage from one or more of the power supply rails;
• a first voltage sub-domain coupled to the one or more power supply rails through a first supply branch, the first voltage sub-domain including at least a texture sampler;
• and
• a second voltage sub-domain coupled to the one or more power supply rails through a second supply branch, the second voltage sub-domain including at least an execution unit(EU), wherein:
• at least one of the first and second supply branches includes a second voltage regulator operable to reduce the domain voltage to a sub-domain voltage that maintains the sampler or EU in an active, low power state.

A method of managing performance of a graphics processor core, the method comprising:

• supplying a domain voltage over a power supply rail coupled to a voltage domain including one or more sampler and one or more execution unit (EU);
• monitoring performance demand on the graphics processor core;
• and
• regulating a first sub-domain voltage supplied from the rail and provided to the one or more sampler, based on the monitoring, to below the domain voltage independently of a second sub-domain voltage supplied from the rail and provided to the one or more EU.