Patent ID: 8671380

Claim:
An apparatus comprising: a clock tree coupled to distribute a clock signal to each of a plurality of leaf nodes, wherein each leaf node is coupled to one or more synchronous circuits; a plurality of fine-grain clock gating units, wherein each of the plurality of fine-grain clock gating units is configured to gate the clock signal provided to each of the one or more synchronous circuits of a corresponding one of the plurality of leaf nodes; a functional unit including a number of the plurality of fine-grain clock gating units in a subset of the plurality of leaf nodes; a coarse clock gating unit configured to gate the clock signal for each of the subset of the plurality of leaf nodes; a gating control unit coupled to the coarse clock gating unit, wherein the gating control unit is configured to selectively control a frequency of the clock signal provided to each of the subset of the plurality of leaf nodes by enabling one of every N cycles of the clock signal and inhibiting N-1 of every N cycles of the clock signal, wherein N is an integer value that is greater than one; and wherein the gating control unit is configured to dynamically change the frequency without suspending operation of the functional unit.