Grid vs Stacked SLR Crossing Reporting - 2025.1 English - UG906

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

Document ID
UG906
Release Date
2025-05-29
Version
2025.1 English

For multi-SLR single column devices, the estimate of the resources used at the post place stage is accurate. There can be some minor movements across SLR to improve timing, but paths that cross multiple SLRs are accounted for in each SLR crossing numbers. For example, SLR0-SLR2 must go SLR0-SLR1-SLR2, and a route is included in each crossing.

For multi-SLR multi-column devices, the estimated resources used at the post place stage assumes the router uses adjacent SLRs where possible. However, in these devices, there is more than one possible solution to route from SLRm to SLRn. For example, in a 2x2 SLR device, going between SLR0 to SLR1 can go directly to SLR0-SLR1 or SLR0-SLR3-SLR2-SLR1. When usage between two adjacent SLRs is over 100%, it can still be possible to route by choosing a slower alternative route (SLR0-SLR3-SLR2-SLR1). Diagonal routes between SLRs, for example SLR0-SLR2 and SLR1-SLR3, are captured as one vertical and one horizontal route as shown in the following figure:

Figure 1. 2x2 SLR Crossing Place

After routing is complete, only the actual routing used is shown.

The SLR CLB Logic and Dedicated Block Utilization table shows the resource utilization for each SLR. This can be toggled using the % icon which can help with analysis of the SLR partition.

Figure 2. Utilization in Each SLR