Programmable measurement mode for a serial point to point link

An integrated circuit (IC) device, comprising:

• an analog front end (AFE) transmit block coupled to a serial point to point link;
• an AFE receive block coupled to the serial point to point link;
• and
• measurement mode circuitry (MMC) to provide the AFE transmit block a sequence of test symbols to be transmitted over the link while the link is operating in a measurement mode, the MMC to evaluate a sequence of test symbols, received by the AFE receive block over said link, for errors,
• wherein the IC device is to enter the measurement mode from a normal mode in response to a predefined bit of a register of the IC device being programmed, the IC device having one or more programmable registers whose bits instruct the MMC to change a data pattern in the sequence of test symbols and one of a) an autoinvert setting, b) a default setting for an inverted lane of the link, c) an inversion setting, and d) initial disparity, for the link.

A system comprising:

• a processor;
• a main memory;
• and
• an integrated circuit (IC) device which is communicatively coupled to the processor and the main memory and provides the processor with I/O access, the IC device having link interface circuitry that supports a serial point to point link, the link interface circuitry includes
• an analog front end (AFE) transmit block coupled to the link;
• an AFE receive block coupled to the link;
• and
• measurement mode circuitry (MMC) to provide the AFE transmit block a sequence of test symbols to be transmitted over the link while the link is operating in a measurement mode, the MMC to evaluate a sequence of test symbols, received by the AFE receive block over said link, for errors,
• wherein the IC device is to enter the measurement mode from a normal mode in response to a predefined bit of a register of the IC device being programmed, the IC device having one or more programmable registers whose bits instruct the MMC to change a data pattern in the sequence of test symbols and one of a) an autoinvert setting, b) a default setting for an inverted lane of the link, c) an inversion setting, and d) initial disparity, for the link.