Clocking synchronization method and apparatus

A method for communication, comprising:

• performing, by an endpoint communication node, a clock training handshake with a host communication node;
• entering, by the endpoint communication node, a clock training period, on successful performance of the clock training handshake;
• entering, by the endpoint communication node, a start static phase measurement (SSPM) sequence of clock training period, and receiving a clocking pattern from the host communication node;
• and
• processing, by a phase frequency detector (PFD) of the endpoint communication node, the clocking pattern to determine parts-per-million (PPM) differences with the host communication node;
• determining, by a static phase measurement (SPM) controller of the endpoint communication node, a PPM correction, and providing the determined PPM correction to a phase lock loop (PLL) of the endpoint communication node;
• and
• applying, by the PLL, the PPM correction to compensate for the PPM differences determined during subsequent clocking synchronization.

A communication node, comprising:

• a physical layer having a logical sub-block, and an electrical sub-block;
• wherein the logical sub-block includes clock and link training and management logic arranged to:
• perform a clock training handshake with an endpoint communication node;
• instruct the endpoint communication node to start static phase measurement as part of the clock training, on successful completion of the clock training handshake;
• provide a clock pattern to the endpoint communication node until receipt of an acknowledgement from the endpoint communication node;
• and
• instruct the endpoint communication node to start clocking synchronization, on receipt of the acknowledgment;
• wherein clocking synchronization comprises spread spectrum clocking (SSC) synchronization;
• the clock and link training and management logic is further arranged to provide the endpoint communication node with an SSC pattern, on instructing the endpoint communication node to start SSC synchronization;
• wherein the acknowledgement is a first acknowledgment, and wherein the clock and link training and management logic is arranged to provide the endpoint communication node with the SSC pattern, until receipt of a second acknowledgment.

A communication node, comprising:

• a physical layer having a logical sub-block, and an electrical sub-block;
• wherein the logical sub-block includes clock and link training and management logic arranged to:
• perform a clock training handshake with a host communication node;
• receive instruction from the host communication node to start static phase measurement as part of the clock training, on successful completion of the clock training handshake;
• receive a clock pattern from the host communication node;
• provide an acknowledgement to the host communication node on successful completion of the static phase measurement;
• receive instruction from the host communication node to start clocking synchronization;
• and
• start clocking synchronization to the host communication node;
• wherein clocking synchronization comprises spread spectrum clocking (SSC) synchronization;
• the clock and link training and management logic is further arranged to provide an endpoint communication node an SSC pattern;
• wherein the acknowledgement is a first acknowledgment, and wherein the clock and link training and management logic is arranged to provide to the host communication node a second acknowledgment, on completion of SSC synchronization.