IC Compiler SoC Design Planning
In this hands-on workshop, you will use IC Compiler to create chip- and block-level floorplans, using a hierarchical (top-down) design planning approach. The focus is on multi-voltage (UPF) system-on-a-chip (SoC) designs, which contain multiply-instantiated macros (MIMs) where the MIMs are initially treated as “black boxes”, and are later re-floorplanned as fully-synthesized sub-blocks.
Day 1 starts with a brief overview of “data setup” for “multi-corner multi-mode” (MCMM) timing analysis, then focuses on the creation of a hierarchical floorplan of a chip-level design with black boxes, including multiply-instantiated macro (MIM) black boxes. This includes a methodology for determining optimum placement of macros and placement blockages.
Day 2 covers Template-based Power Network Synthesis (TPNS) to design a complex multi-voltage chip-level power network, which is “pushed down” into the physical sub-blocks. The hierarchical design-planning flow is then revisited, for a fully-synthesized design (no black boxes): This includes placement and shaping of plan groups (which represent the physical sub-designs) as well as MIMs, and handling voltage areas of a multi-voltage design. “Data Flow Analysis” (DFA) is used to aid in macro array placement.
Day 3 covers the creation of soft macros based on the plan groups. This includes final pin placement and derivation of block-level timing constraints. The soft-macro floorplans are saved in individual libraries so the block can be individually re-synthesized with Design Compiler Topographical, and then “implemented” (placed and routed) in IC Compiler. “On-Demand Loading” (ODL) is introduced to improve floorplanning runtime and memory requirements. Finally, soft-macro floorplans are completed to include power switching (creation of a power switch array, connecting the sleep control, adjusting the power network).
Most lectures are accompanied by a comprehensive hands-on lab.
At the end of this workshop you should be able to use IC Compiler to:
- Perform multi-corner multi-mode (MCMM) data setup to create an initial design cell, which is ready for design planning, including importing netlists with black boxes
- Create a hierarchical chip-level floorplan for a multi-voltage SoC design:
- Define core area and pad cell placement in the periphery area
- Apply size estimates for black boxes and black box MIMs
- Create QTMs (Quick Timing Models) for black boxes for chip level timing analysis
- Define plan groups for sub-designs
- Create, shape and place the plan groups, as well as voltage areas
- Determine ideal chip-level placement of black boxes, MIMs and macros
- Use TPNS to build the physical power network
- Manual and automatic placement strategies for macros, using "virtual flat placement"
- Define pin placement of physical sub-designs
- Use TPNS to perform multi-voltage power network design
- Create power plan regions
- Define strategies and templates for rings and meshes
- Preview and compile the power network
- Analyze LVS issues and IR drop
- Push down power structure into blocks
- Analyze and improve macro placement using DFA
- Analyze congestion
- Create soft macros based on the plan groups:
- Make adjustments to an existing, or add new TPNS strategies to address changes in the floorplan
- Analyze the power network using the built-in "Network Analysis" feature
- Perform final pin assignment and analysis on plan groups
- Analyze timing and perform "place optimization" (IPO) on the top level netlist
- Create timing budgets for sub-designs
- "Commit" the plan groups to soft macros
- Write floorplan files for resynthesis in Design Compiler Topographical and for re-use in IC Compiler
- Use ODL to reduce floorplanning runtime and memory usage
- Complete the block-level floorplan:
- Read and constrain a block level design using information from chip-level floorplanning
- Create a power switch array, and connect the sleep control
- Modify a "normal" TPNS template to line up with power switches, and make the necessary modifications to the strategies
- Understand the pros and cons of using DEF versus Tcl floorplan files for DC-T and ICC
- Link the top level design with the implemented block level designs
ASIC, back-end, or layout designers who will be using IC Compiler to perform design planning on multi-voltage SoC designs.
Prior knowledge of IC Compiler is not needed. An understanding of fundamental floorplanning concepts is required. Must be able to use a text editor (vi, vim, emacs) in a UNIX environment.
- MCMM Data Setup (Lecture)
- Chip-Level Design Planning with Black Boxes (Lecture + Lab)
- Multi-Voltage Power Network Design (Lecture + Lab)
- Design Planning with Plan Groups and Voltage Areas (Lecture + Lab)
- Committing Plan Groups to Soft Macros (Lecture + Lab)
- On-Demand Loading (Lecture)
- Block-Level Floorplanning (Lecture + Labs)
Synopsys Tools Used
- IC Compiler 2013.12-SP4
- IC Validator 2013.12-SP2