Intel® Quartus® Prime Pro Edition User Guide: Design Optimization

ID 683641
Date 10/02/2023
Document Table of Contents Defining Empty Logic Lock Regions

The Intel® Quartus® Prime supports the use of Logic Lock regions without any members. You can use such empty regions to reserve device resources to contain logic to be add later. This technique require that you turn on the region's Reserved setting to prevent the Fitting from placing any other logic within this region.

Empty Logic Lock regions can be useful for the following scenarios:

  • Preliminary floorplanning
  • Complex incremental builds, such as root partition reuse
  • Team based design and interconnect logic
  • Confining logic placements

Since Logic Lock regions do not reserve any routing resources by default, the Fitter may use the reserved area for routing purposes.

Use the Core Only attribute for empty Logic Lock regions. When you include periphery resources in empty regions, you restrict the periphery component placement, which can result in a no fit design. After you name the empty region, you can perform the same manipulations as with any Logic Lock region that includes members.

Figure 116. All Logic Placed Outside an Empty regionThe figure shows an empty Logic Lock region and the logic placed around it. However, some I/Os, HSSIO, and PLLs are present in the empty region because the output port connects to the I/O that is part of the root_partition (top-level partition).