Debugging QoR Suggestions - 2024.1 English

Vivado Design Suite User Guide: Design Analysis and Closure Techniques (UG906)

Document ID
UG906
Release Date
2024-06-05
Version
2024.1 English

Sometimes it can be necessary to delve deeper into the suggestion to understand the reason for generation. There are typically a few things that should be investigated

  • Utilization and Netlist Suggestions
    • These typically require investigation of the cells in the netlist that the suggestion is targeting. This can be done by selecting objects and opening a schematic.
  • Clocking and Timing Suggestions
    • These typically require investigation of the timing path associated with the suggestion. The timing reports form part of the QoR Suggestion report.
  • Congestion Suggestions
    • These typically require investigation of the cells and their location.
To get a cell list of targeted objects in a suggestion, follow the steps to write out a Tcl file. When the Tcl suggestion file is written, each suggestion is labeled in the file with its ID. From this a user can copy the [get_cells <>] or [get_nets <nets>] portion of the suggestion. The following is an example of Tcl that can be used to further explore the objects:
set cells <cells from Tcl file>
report_timing -from $cells 
report_design_analysis -of [get_timing_paths -from $cells -max_paths 100] -name -RQS
show_objects -name RQS_objs $cells
select_objects [get_sites -of $cells]