Completion-triggered forwarding of direct memory access transfers between coarse-grained reconfigurable processors

A system comprising:

• a first coarse-grained reconfigurable processor (CGRP) comprising:
• a first set of coarse-grained reconfigurable units (CGRUs) including a first CGRU;
• a first top-level network (TLN) coupled to each CGRU of the first set of CGRUs;
• a first external network interface (ENI) for communication over a first external network;
• a second ENI for communication over a second external network;
• and
• a first external network shim (Eshim) including a first external direct memory access (EDMA) engine, the first Eshim configured to:
• receive, over the first external network, a first transfer frame of a first direct memory access (DMA) transfer from a second CGRP, the first transfer frame comprising a first header and first frame data;
• initiate a memory write of the first frame data over the first TLN to a first memory;
• receive a first completion message over the first TLN that indicates the memory write has completed;
• and
• in response to the first completion message, trigger a second DMA transfer of a second transfer frame to a third CGRP over the second external network, the second transfer frame comprising a second header and a first subset of the first frame data.

A non-transitory computer-readable medium storing instructions that, when executed, cause a first external network shim (Eshim) of a first coarse-grained reconfigurable processor (CGRP) to perform operations, the first CGRP comprising a first set of coarse-grained reconfigurable units (CGRUs) including a first CGRU, a first top-level network (TLN) coupled to each CGRU of the first set of CGRUs, a first external network interface (ENI) for communication over a first external network, a second ENI for communication over a second external network, and the first Eshim, wherein the first Eshim includes a first external direct memory access (EDMA) engine, and wherein the operations comprise:

• receiving, by the first Eshim over the first external network, a first transfer frame of a first direct memory access (DMA) transfer from a second CGRP, the first transfer frame comprising a first header and first frame data;
• initiating a memory write of the first frame data over the first TLN to a first memory;
• receiving a first completion message over the first TLN that indicates the memory write has completed;
• and
• in response to the first completion message, triggering a second DMA transfer of a second transfer frame to a third CGRP over the second external network, the second transfer frame comprising a second header and a first subset of the first frame data.