Clock synchronization using digitally controlled oscillator

A system, comprising:

• a digitally controlled oscillator (DCO) to generate a local clock having a local clock frequency;
• a hardware clock to maintain a time-of-day value advancing at a frequency proportional to the local clock frequency of the local clock output by the DCO;
• and
• clock synchronization circuitry to:
• synchronize the hardware clock to a remote device;
• generate a digital control command;
• and
• provide the digital control command to the DCO, wherein the DCO is to adjust the local clock frequency responsively to the digital control command.

A method, comprising:

• generating, by a digitally controlled oscillator (DCO), a local clock signal having a local clock frequency;
• maintaining a value indicative of a local clock time advancing at a frequency proportional to the local clock frequency of the local clock signal generated by the DCO;
• receiving from a device an indication of a remote clock time;
• generating a digital control command to at least partially correct for a difference between the remote clock time and the local clock time;
• providing the digital control command to the DCO;
• and
• adjusting, by the DCO, the local clock frequency responsively to the digital control command.