Devices transferring cache lines, including metadata on external links

A method, in a device, of a conversion circuit providing a flow control unit (FLIT) to a link interface circuit of the device, the method comprising:

• receiving, in a conversion circuit, a write instruction, at least a first cache line, and metadata associated with the at least a first cache line on a system bus;
• generating a FLIT comprising:
• a first header slot comprising write information based on the write instruction for transmitting the at least one first cache line on an external link coupled to the link interface circuit;
• a first metadata slot comprising the metadata;
• and
• at least two generic slots comprising cache line chunks, each cache line chunk comprising bytes of a cache line;
• and
• providing the FLIT to the link interface circuit for transmission on the external link.

A device comprising:

• data storage;
• a link interface circuit coupled to an external link;
• a conversion circuit coupled to the link interface circuit and the data storage, the conversion circuit configured to:
• receive, from the link interface circuit, a read flow control unit (FLIT) comprising a read instruction requesting at least one cache line from the data storage;
• generating a response FLIT comprising:
• a header slot comprising response information based on the read instruction for the at least one first cache line;
• a first metadata slot comprising metadata associated with the at least one first cache line;
• and
• at least two generic slots, each comprising a cache line chunk, each cache line chunk comprising bytes of one of the at least one first cache line.