Graph-Grammar-Based IP-Integration (GRIP)—An EDA Tool for Software-Defined SoCs

In modern system-on-chip (SoC) designs, IP-reuse is considered a driving force to increase productivity. To support various designs, a huge amount of Intellectual Property (IP) hardware blocks have been developed. The integration of those IPs into an SoC may require significant effort—up to days or weeks depending on experience and complexity. This article presents a novel approach to significantly reduce the design effort to bring-up a working SoC design by automatic IP integration as part of a library-based Software-defined SoC flow. In detail, the IP-supplier prepares a HW-accelerated software library (HASL) for the SoC architect, who wants to use the IP in an SoC design. As a key point of our approach, integration knowledge is encoded in the library as a set of integration rules. These rules are defined in the machine-readable standardized IP-XACT format by the IP supplier, who has a good knowledge of the IP’s hardware details. The library preparation step on the IP supplier’s side is also partly automated in the proposed flow, including a partial generation of configurable HW drivers, schedulers, and the software library functions. For the SoC architect, we have developed the graph-grammar-based IP-integration (GRIP) tool. The software application is developed using the functions supplied in the HASL. According to the calls to the HASL functions, the GRIP tool automatically integrates IP-blocks using the rule information supplied with the library and runs a full Design Space Exploration. For this, the SoC architecture and rules are transformed into the graph domain to apply graph rewriting methods. The GRIP tool is model-driven and based on the Eclipse Modeling Framework. With code generation techniques, SoC candidate architectures can be transformed to hardware descriptions for the target platform. The HW/SW interfaces between SW library functions and IP blocks can be automatically generated for bare-metal or Linux-based applications.

The approach is demonstrated with two case-studies on the Xilinx Zynq-based ZedBoard evaluation board using a HASL for computer vision. It can yield 10×-150× performance improvement for the bare-metal application versions and 4×--7× performance improvement for the Linux-based application versions, when executed on an optimized HW-accelerated SoC architecture compared to a non HW-accelerated SoC. The effort for IP integration is comparable to using a software library, hence, providing a significant advantage over a manual IP integration.