Die-to-die interconnect

A method comprising:

• receiving data at a physical layer block of a port, wherein the port comprises the physical layer block, a protocol layer block, and a die-to-die adapter block between the PHY block and the protocol layer block, and the data is received from the die-to-die adapter via a defined interface connecting the PHY block and die-to-die adapter block, wherein the port couples a first die to a die-to-die (D2D) link, the D2D link couples the first die to a second die, and the D2D link comprises a plurality of lanes;
• sending the data from the first die to the second die over the set of mainband lanes;
• and
• sending sideband data from the first die to the second die over a set of sideband lanes in the plurality of lanes.

A system comprising:

• a first die;
• and
• a second die coupled to the first die by a die-to-die (D2D) link, wherein the second die comprises a port to connect the second die to the D2D link, and the port comprises:
• protocol layer logic;
• die-to-die adapter circuitry;
• and
• physical layer circuitry,
• wherein the die-to-die adapter is positioned between the protocol layer logic and the physical layer circuitry and manages link states for the D2D link, and the physical layer circuitry comprises:
• a first number of sideband lanes for the D2D link, wherein the sideband lanes are to carry data for use in training and management of the D2D link;
• and
• a second number of mainband lanes for the D2D link, wherein the mainband lanes are to implement a main data path of the D2D link, and the second number of mainband lanes comprise a forwarded clock lane, a valid lane, and a plurality of data lanes.