Provision of early data from a lower level cache memory

Abstract

In response to snooping a read-type memory access request of a requestor on a system fabric of a data processing system, a memory channel interface forwards the request to a memory buffer and starts a timer. In response to the forwarded request, the memory buffer performs a lookup of a target address of the request in a memory controller cache. In response to the target address hitting in a coherence state permitting provision of early data, the memory buffer provides a response indicating early data and provides a copy of a target memory block of the request to the memory channel interface. The memory channel interface, responsive to receipt prior to expiration of the timer of the response indicating early data, transmits the copy of the target memory block to the requestor via the system fabric prior to receiving a combined response of the data processing system to the request.