Embodiments include an autonomous core perimeter, configured to save the state of a core of a multi-core processor prior to the processor package being placed into a low-power state. The autonomous core perimeter of each core is configured to save an image of a microcontroller firmware to an external store if it has not been previously saved by another core, along with the unique working state information of that core's microcontroller. Upon restore, the single microcontroller firmware image is retrieved from the external store and pushed to each core along with each core's unique working state.