AN 796: Cyclone® V and Arria® V SoC Device Design Guidelines

ID 683360
Date 3/30/2022
Public
Document Table of Contents

2.1.1.3. FPGA-to-HPS Bridge

GUIDELINE: Use the FPGA-to-HPS bridge for cacheable accesses to the HPS from masters in the FPGA.

The FPGA-to-HPS bridge allows masters implemented in the FPGA fabric to access memory and peripherals inside the HPS. This bridge supports 32, 64, and 128-bit datapaths so that you can adjust it to be as wide as the widest master implemented in the FPGA.

GUIDELINE: Use the FPGA-to-HPS bridge to access cache-coherent memory, peripherals, or on-chip RAM in the HPS from masters in the FPGA.

Although this bridge has direct connectivity to the SDRAM subsystem, the main intent of the bridge is to provide access to peripherals and on-chip memory, as well as provide cache coherency with connectivity to the MPU accelerator coherency port (ACP).

To access the HPS SDRAM directly without coherency you should connect masters in the FPGA to the FPGA-to-SDRAM ports instead, because they provide much more bandwidth and lower-latency access.