The-OpenROAD-Project / OpenROAD

OpenROAD About OpenROAD OpenROAD is the leading open-source, foundational application for semiconductor digital design. The OpenROAD flow delivers an Autonomous, No-Human-In-Loop (NHIL) flow, 24 hour turnaround from RTL-GDSII for rapid design exploration and physical design implementation. OpenROAD Mission OpenROAD eliminates the barriers of cost, schedule risk and uncertainty in hardware design to promote open access to rapid, low-cost IC design software and expertise and system innovation. The OpenROAD application enables flexible flow control through an API with bindings in Tcl and Python. OpenROAD is used in research and commercial applications such as, • OpenROAD-flow-scripts from OpenROAD • OpenLane from Efabless • Silicon Compiler from Zero ASIC • Hammer from UC Berkeley • OpenFASoC from IDEA-FASoC for mixed-signal design flows OpenROAD fosters a vibrant ecosystem of users through active collaboration and partnership through software development and key alliances. Our growing user community includes hardware designers, software engineers, industry collaborators, VLSI enthusiasts, students and researchers. OpenROAD strongly advocates and enables IC design-based education and workforce development initiatives through training content and courses across several global universities, the Google-SkyWater shuttles also includes GlobalFoundries shuttles, design contests and IC design workshops. The OpenROAD flow has been successfully used to date in over 600 silicon-ready tapeouts for technologies up to 12nm. Getting Started with OpenROAD-flow-scripts OpenROAD provides OpenROAD-flow-scripts as a native, ready-to-use prototyping and tapeout flow. However, it also enables the creation of any custom flow controllers based on the underlying tools, database and analysis engines. Please refer to the flow documentation here. OpenROAD-flow-scripts (ORFS) is a fully autonomous, RTL-GDSII flow for rapid architecture and design space exploration, early prediction of QoR and detailed physical design implementation. However, ORFS also enables manual intervention for finer user control of individual flow stages through Tcl commands and Python APIs. Figure below shows the main stages of the OpenROAD-flow-scripts: Here are the main steps for a physical design implementation using OpenROAD; • - Floorplan initialization - define the chip area, utilization • IO pin placement (for designs without pads) • Tap cell and well tie insertion • PDN- power distribution network creation • - Macro placement (RAMs, embedded macros) • Standard cell placement • Automatic placement optimization and repair for max slew, max capacitance, and max fanout violations and long wires • - Legalize placement - align to grid, adhere to design rules • Incremental timing analysis for early estimates • - Insert buffers and resize for high fanout nets • • - Antenna repair • Create routing guides • - Legalize routes, DRC-correct routing to meet timing, power constraints • - Parasitic extraction using OpenRCX • Final timing verification • Final physical verification • Dummy metal fill for manufacturability • Use KLayout or Magic using generated GDS for DRC signoff GUI The OpenROAD GUI is a powerful visualization, analysis, and debugging tool with a customizable Tcl interface. The below figures show GUI views for various flow stages including floorplanning, placement congestion, CTS and post-routed design. Floorplan Automatic Hierarchical Macro Placement Placement Congestion Visualization CTS Routing PDK Support The OpenROAD application is PDK independent. However, it has been tested and validated with specific PDKs in the context of various flow controllers. OpenLane supports SkyWater 130nm and GlobalFoundries 180nm. OpenROAD-flow-scripts supports several public and private PDKs including: Open-Source PDKs • - 180nm • - 130nm • - 45nm • - Predictive FinFET 7nm Proprietary PDKs These PDKS are supported in OpenROAD-flow-scripts only. They are used to test and calibrate OpenROAD against commercial platforms and ensure good QoR. The PDKs and platform-specific files for these kits cannot be provided due to NDA restrictions. However, if you are able to access these platforms independently, you can create the necessary platform-specific files yourself. • - 55nm • - 12nm • - 22nm • - 16nm • - 65nm Tapeouts OpenROAD has been used for full physical implementation in over 600 tapeouts in SKY130 and GF180 through the Google-sponsored, Efabless MPW shuttle and ChipIgnite programs. OpenTitan SoC on GF12LP - Physical design and optimization using OpenROAD Continuous Tapeout Integration into CI The OpenROAD project actively adds successfully taped out MPW shuttle designs to the CI regression testing. Examples of designs include Open processor cores, RISC-V based SoCs, cryptocurrency miners, robotic app processors, amateur satellite radio transceivers, OpenPower-based Microwatt etc. Build OpenROAD To build OpenROAD tools locally on your machine, follow steps from here. Regression Tests There are a set of executable regression test scripts in . The flow tests check results such as worst slack against reference values. Use to see all of the metrics. To update a failing regression, follow the instructions below: Run OpenROAD sources the Tcl command file unless the command line option is specified. OpenROAD then sources the command file if it is specified on the command line. Unless the command line flag is specified, it enters an interactive Tcl command interpreter. A list of the available tools/modules included in the OpenROAD app and their descriptions are available here. Git Quickstart OpenROAD uses Git for version control and contributions. Get familiarised with a quickstart tutorial to contribution here. Understanding Warning and Error Messages Seeing OpenROAD warnings or errors you do not understand? We have compiled a table of all messages and you may potentially find your answer here. License BSD 3-…