Hello everyone, I want to place multiple macros in caravel user area, but I can not do this effectively. Although I leave about 200 um of gaps between macros, there are congestion errors when I run the flow. But I see many projects with much closer macro placements, so I think I miss an essential point. What are the key points to place macros closely?

First try with auto macro placement and see the routing. If its fails you've to go with manual macro placement. Based on macro pin connection, place macro near to core edge and pin connection. Use

set ::env(PL_MACRO_CHANNEL) {30 30}
set ::env(PL_MACRO_HALO) {10 10}

above for MACRO spacing. This will sure fix your issues

I didnt know about auto macro placement, got a link to any docs?

@User If there is LEF/GDS variable define, tool will look for

marco.cfg

or OpenROAD app will do auto macor placement

Thanks for the tip, it really solved the problem. But I really wonder what this config exactly do, what it changes and how it solves the problem.