Quartus® Prime Standard Edition User Guide: Design Compilation

ID 683283
Date 10/22/2021
Public
Document Table of Contents

1.9.2. Changing Partition Placement with LogicLock Changes

When a partition is assigned to a LogicLock region as part of a design floorplan, you can modify the placement of a post-fit partition by moving the LogicLock region. Most assignment changes do not initiate a recompilation of a partition if the netlist type specifies that Fitter results should be preserved. For example, changing a pin assignment does not initiate a recompilation; therefore, the design does not use the new pin assignment unless you change the netlist type to Post Synthesis or Source File.

Similarly, if a partition’s placement is preserved, and the partition is assigned to a LogicLock region, the Fitter always reuses the corresponding LogicLock region size specified in the post-fit netlist. That is, changes to the LogicLock Size setting do not initiate refitting if a partition’s placement is preserved with the Post-Fit netlist type, or with .qxp that includes post-fit information.

However, you can use the LogicLock Origin location assignment to change or fine‑tune the previous Fitter results. When you change the Origin setting for a region, the Fitter can move the region in the following manner, depending upon how the placement is preserved for that region's members:

  • When you set a new region Origin, the Fitter uses the new origin and replaces the logic, preserving the relative placement of the member logic.
  • When you set the region Origin to Floating, the following conditions apply:
    • If the region’s member placement is preserved with an imported partition, the Fitter chooses a new Origin and re-places the logic, preserving the relative placement of the member logic within the region.
    • If the region’s member placement is preserved with a Post-Fit netlist type, the Fitter does not change the Origin location, and reuses the previous placement results.