Presentation
Net Resource Allocation: A Desirable Initial Routing Step
DescriptionIn modern IC design, routing significantly impacts chip performance, power, area, and design iteration count. Critical challenges in routing include generating rectilinear Steiner minimum tree (RSMT) for each net and handling routing resource among nets. Due to limited resources and net scale, congestion is inevitable in VLSI circuit routing. Most competitive routers address congestion after routing without prior net guidance, leading to difficulty in managing resources among nets. To tackle routing and congestion, we suggest introducing a net resource allocation step as a potentially desirable initial routing stage. Firstly, we introduce the concept of net region probability density (NRPD) to achieve suitable net resource allocation. Using a prior NRPD, we model the resource allocation problem as quadratic programming (QP). We utilize penalty method to solve the QP quickly and obtain a posterior NRPD for each net on each grid. Based on the posterior NRPD and congestion map, we introduce a cost scheme to guide net routing. This cost scheme supports a weighted RSMT construction technique for better topological solutions. Additionally, we propose an iterative method for global routing and track assignment, improving detailed routing quality and optimizing design rule violations. Experimental results show the effectiveness of net resource allocation and demonstrate superior performance of our router over the OpenROAD's router across multiple metrics.
Event Type
Research Manuscript
TimeWednesday, June 264:00pm - 4:15pm PDT
Location3010, 3rd Floor
EDA
Physical Design and Verification