Agilex™ 5 ES Device Errata and User Guidelines

ID 825514
Date 12/09/2024
Public
Document Table of Contents

2.2.2. USB 3.1 AxADDR width is limited to 32-bit

Description

The USB 3.1 controller is limited to an AXI address width of 32-bits, and therefore, can only access up to 4 GBytes of system memory address space.

Workaround

If your application needs to access address space larger than 4 GBytes, such as the 256 GByte address space of the HPS-to-FPGA bridge, then SMMU needs to reprogram to allocate different 4 GByte of address space in system memory compared to earlier allocation. Overall, USB data processing will be slower due to SMMU reprogramming overhead.