runtime Directory Reference

Directory dependency graph for runtime:

Directories
	cosim_dpi_server
	cpp
	docs
	python
	tests

Files
	setup.py

Detailed Description

ESI Accelerator Runtime

The ESI Accelerator Runtime (esiaccel) provides software APIs and tools for interacting with accelerators built using CIRCT's Elastic Silicon Interconnect (ESI) dialect. It includes Python bindings and C++ libraries for discovering an accelerator's hierarchy, communicating over typed channels, and accessing services such as MMIO and host memory.

Installation

The ESI Accelerator Runtime requires Python 3.8 or newer.

pip install esiaccel

Getting started

See the ESI documentation for an overview of ESI. The package includes support for connecting to accelerators through RTL cosimulation and Xilinx Runtime (XRT) backends.

For command-line accelerator discovery and inspection, run esiquery --help. The ESI Accelerator Runtime is developed as part of the CIRCT repository.

Cosim HostMem width

The cosim BSP accepts a hostmem_width parameter in bits, shared by reads and writes:

CosimBSP(MyDesign, hostmem_width=512)

The default is 64 bits. Supported widths are powers of two, at least 8 bits. CosimBSP_DMA accepts the same parameter. The host runtime discovers the width from the design's channel types; no corresponding software setting is needed.

Wider beats reduce transport messages for wide writes: a 4096-byte write takes 512 beats at 64 bits, but only 64 beats at 512 bits. Each beat is still acknowledged, and the client receives completion after all its beats complete. Reads similarly return fewer, wider response beats. Short reads access only the requested bytes; unused bytes in the final response beat are zero-filled. Separate narrow client requests are not combined. The cosim read-request and write-payload caps remain 256 bytes unless one configured beat is larger, in which case the caps grow to accommodate that beat.