Methods and apparatus to selectively power functional units

摘要

A processing engine fetches one or more lines of software instructions into an instruction cache. Based on the contents of the cache, potentially needed functional units are identified as functional units that are operable to execute at least one software instruction stored within the instruction cache. Unneeded functional units are identified as functional units that are not operable to execute a software instruction stored within the instruction cache. A power increase is initiated for selected ones of the potentially needed functional units that are determined to be in a low power state. A power decrease is initiated for selected ones of the unneeded functional units that are determined to be in an operable power state.

主权项

1. A method comprising:
generating an information vector per each cache line of an instruction cache, the instruction cache including a plurality of cache lines, the information vector including a plurality of fields, each field associated with a corresponding functional unit among one or more functional units; determining a value of a use counter associated with a functional unit among the one or more functional units as indicating that the functional unit is needed to execute at least one software instruction stored within the instruction cache; controlling a power level of the functional unit based on the value of the use counter; and executing the at least one software instruction by the functional unit based on the information vector.