AI-Accelerated: Synaptics’ ARC HS58x3 Migration with Synopsys QIK and DSO.ai “Warm Start”

Optimizing for ARC Processor Migration

The upgrade to ARC HS58 provided significant improvements in several areas necessary for DL-7400:

• HS58 came with a 2.5X gain in memory bandwidth. 
• Compression speed was measured at more than 1.25X faster while decompression speed clocked in at 1.12X faster. 
• The processor offers intensive computation for large data arrays stored in memory with a 50% better performance executing the same number of instructions.
• Finally, the HS58 provided an average of 48% better performance when measured on silicon.

For the migration to be successful, several software and implementation challenges had to be met. First off, the software needed to be preserved. Minimizing changes was crucial because a significant amount of investment was placed into developing unique and complex software. On the implementation side, the footprint had to match that of the HS38 including the physical area, pins, location, and power distribution. The I/O timing and clock latency needed to meet the existing SoC while dynamic leakage power needed to be reduced. To achieve all the benefits of the ARC HS58 processor without having to perform a complete redesign, Synaptics turned to Synopsys QuickStart Implementation Kit (QIK), Fusion Compiler™, and DSO.ai™.

The Synopsys QIK is a complete solution consisting of the best-in-class IPs, libraries, tools, and methodologies, services, and support. QIKs were made to implement Synopsys IP as they are created in close collaboration with IP design, R&D, and methodology experts, provide a fully worked example that meets QoR targets, include a recommended flow with scripts (implementation, ECO, signoff, formal verification, core configuration, and constraints), incorporate either flat or hierarchical flows, and are easy to customize for project-specific needs.

Synopsys DSO.ai autonomously explores multiple design spaces to optimize PPA metrics while minimizing tradeoffs for the target application. It uses AI to navigate the design-technology solution space by automatically adjusting or fine-tuning the inputs to the design (e.g., settings, constraints, process, flow, hierarchy, and library) to find the best PPA targets. 

For new designs, Synopsys DSO.ai takes these inputs in what is called a “cold start” to identify those prime targets. However, the solution learns from the initial design optimization and can apply these learnings to derivative designs so that rather than starting “cold,” the AI engine gets a “warm start” when it comes to figuring out the best optimization strategies to meet target specifications, saving 5-10X compute resources. This technique was utilized in the migration to the new processor; the HS58 configuration was compared against the original HS38 implemented in the SoC. Then, the HS58 design was run through the QIK flow and then through the Synopsys DSO.ai "warm start" to achieve the best targets for that processor.

Using Synopsys DSO.ai not only dramatically reduced turn-around-time, but also yielded significant reductions in timing requirement violations while improving power consumption and power leakage beyond what the Synopsys QIK would have produced on its own. Synopsys DSO.ai reduced WNS by 23%, TNS by 61%, and Hold TNS by 92%. Total power was improved by 2.2% and leakage power by 19.6%.