Quality of Results (QoR)

Tackle an Unroutable Design in InTime: Part 1

287 views November 15, 2019 November 15, 2019 harnhua 0

If your design is unable to route, it can be due to a variety of reasons.
One simple reason is that placement and routing may need a bit more tuning.
Here is an easy way to try different implementation options to get it to pass the routing stage.
  1. Open your design in InTime.
  2. Select the "InTime Default" recipe in the recipe dropdown menu.
  3. Go to Current Project > Setting Filters
  4. Select post-synthesis settings and add them to the Whitelist.
    (Vivado) The relevant stages are: Opt Design, Place Design, Phys Opt Design, Route Design and Post-route Phys Opt Design
  5. Click "Apply" and then "Close" to confirm the Setting Filters.
  6. Under Properties,

    Set Runs per Round to 10 (as many as your infrastructure can execute in parallel up to 20).
    Set Rounds to 3 (learning happens at each round).
    Set Parent Revision > Initial Compilation to "Skip".
    Make sure that Strategies > Max Runtime is long enough to let each build complete.
  7. Right-click any existing result in the History panel and select 'Unset Parent Revision"

    (If there is no such option, it means that the Parent Revision is already set to your original design)
    This ensures that your original design is used as the reference for analysis and optimization.
  8. Click the "Optimize" button to start the recipe.
InTime will now tune the post-synthesis options in an attempt to get a routed design.

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