SLR Utilization Considerations - 2023.2 English

UltraFast Design Methodology Guide for FPGAs and SoCs (UG949)

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2023.2 English

The Vivado implementation tools use a special algorithm to partition logic into multiple SLRs. For challenging designs, you can improve timing closure for designs that target SSI technology devices using the following guidelines.

To improve timing closure and compile times, you can use Pblocks to assign logic to each SLR and validate that individual SLRs do not have excessive utilization across all fabric resource types. For example, a design with block RAM utilization of 70% might cause issues with timing closure if the block RAM resources are not balanced across SLRs and one SLR is using over 85% block RAM.

Tip: You can define SLR Pblocks by specifying a complete SLR (e.g., resize_pblock pblock_SLR0 -add SLR0).