Abstract: A new approach of systems and methods to support a hierarchical interrupt propagation scheme for efficient interrupt propagation and handling is proposed. The hierarchical interrupt propagation scheme organizes a plurality of slave interrupt handlers associated functional blocks in a chip in a hierarchy. When an exception or error condition occurs in a functional block, a slave interrupt handler associated with the functional block creates an interrupt packet as an interrupt notification and utilizes pre-existing input and output interfaces that have already been utilized for accessing registers of the functional block to transmit the created interrupt packet to a central interrupt handler through the hierarchy without running dedicated interconnect wires out of the functional block.

Abstract: A transmit portion of a network device including a medium access control (MAC) module configured to receive a frame of data to be transmitted from the network device in accordance with a MAC security (MACsec) protocol. In response to the frame of data being a precise time protocol (PTP) frame, the MAC module is configured to encrypt the PTP frame in accordance with the MACsec protocol, and associate an identifier with the encrypted PTP frame. A physical layer module includes a transmit module configured to transmit the encrypted PTP frame from the network device at a particular time. A PTP module configured to, based on the identifier associated with the encrypted PTP frame, generate a time stamp indicating the particular time that the transmit module transmits the encrypted PTP frame from the network device. The time stamp is transmitted from the network device along with the encrypted PTP frame.