Hard Processor System Technical Reference Manual: Agilex™ 5 SoCs

ID 814346
Date 7/19/2024
Public
Document Table of Contents

5.6.5.10.2.1. IO Connection

USB 3.1 IO ports are connected to the transceiver of the FPGA. There are no USB 3.1 ports connected directly to FPGA logic. The following figure shows the IO connections.

Figure 174. IO Connections

The host_port_overcurrent and pipe_PowerPresent signals are driven from soft-logic in FPGA fabric. If these signals are not in the right state at the beginning, the USB 3.1 controller cannot perform the required functionalities. For the HPS bootup flow, it is not necessary that FPGA fabric comes up out of reset before HPS. Thus, it is planned to drive the default state of these signals from the System Manager Configuration Register such that the USB 3.1 controller performs its basic functionalities without the FPGA fabric being configured. The mask/override logic is shown in previous figure. The bit-13 and bit-14 of the USB3 Misc Control Register 0 are used for driving mask/override to host_port_overcurrent and pipe_PowerPresent. The hub_vbus_ctrl is for port power to each downstream ports. It is routed to fabric for board.