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

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

2.1.1.2. HPS-to-FPGA Bridge

GUIDELINE: Use the HPS-to-FPGA bridge to connect memory hosted by the FPGA to the HPS.

The HPS-to-FPGA bridge allows masters in the HPS such as the microprocessor unit (MPU), DMA, or peripherals with integrated masters to access memory hosted by the FPGA portion of the SoC device. This bridge supports 32, 64, and 128-bit datapaths, allowing the width to be tuned to the largest slave data width in the FPGA fabric connected to the bridge. This bridge is intended to be used by masters performing bursting transfers and should not be used for accessing peripheral registers in the FPGA fabric. Control and status register accesses should be sent to the lightweight HPS-to-FPGA bridge instead.

GUIDELINE: If memory connected to the HPS-to-FPGA bridge is used for HPS boot, ensure that its slave address is set to 0x0 in Platform Designer (Standard).

When the HPS BSEL pins are set to boot from FPGA (BSEL = 1) the processor executes code hosted by the FPGA residing at offset 0x0 from the HPS-to-FPGA bridge. This is the only bridge that can be used for hosting code at boot time.