Intel Agilex® 7 M-Series FPGA Network-on-Chip (NoC) User Guide

ID 768844
Date 12/04/2023
Public
Document Table of Contents

3.4.2. Connectivity Guidelines: NoC Initiators for Fabric AXI4 Managers

The NoC Initiator Intel FPGA IP uses a separate NoC initiator bridge for each AXI4 subordinate interface that you specify when configuring the IP. If you configure the IP with AXI4 Lite subordinate interfaces, these interfaces all share the bandwidth of the first NoC initiator bridge that the IP uses. If you configure the IP with only AXI4 Lite interfaces, all the AXI4 Lite subordinates share a single physical NoC initiator bridge.

If you configure the NoC Initiator Intel FPGA IP with unequal read and write AXI4 data widths, the IP exposes two AXI4 subordinate interfaces per initiator bridge. One of these interfaces uses the Fabric NoC and is only for read transactions, as Fabric NoC describes. This interface has only the AXI4 AR and R channels. The other interface is only for write transactions, having only the AXI4 AW, W, and B channels. Configure these AXI4 subordinate interfaces for compatibility with the AXI4 managers in your design.

If you configure the NoC Initiator Intel FPGA IP for per-interface clock and reset signals, there are separate clock and reset connections for each AXI4 and AXI4 Lite subordinate interface. Otherwise, there is a single clock and reset to provide clocking and reset to all AXI4 interfaces, and another single clock and reset to provide clocking and reset to all AXI4 Lite subordinates. Connect the clock and reset interfaces to clock and reset sources in your design. Each AXI4 or AXI4 Lite subordinate interface must be synchronous to its clock and reset connections.

AXI4 resets are active-low and you can assert the resets asynchronously. However, you must deassert AXI4 resets on a rising edge of the clock that you use to drive data and handshake signals of the associated AXI4 interfaces.

If you choose to configure the NoC Initiator Intel FPGA IP with a read data width of 512 or 576 bits, you can also configure the IP with a separate clock for the NoC initiator bridges. In this case, the IP exposes an additional clock input. Interface Planner displays each NoC initiator bridge as a AXI4 NoC manager interface, whether configured for AXI4, AXI4 Lite, or both. The AXI4 NoC manager interfaces do not exist in the RTL representation of this IP.

  • If you are using the Platform Designer connection flow, as NoC Design Flow Options describes, instantiate your NoC IP in Platform Designer and connect each AXI4 NoC manager interface to one or more AXI4 NoC subordinate interfaces in the System View tab. Only connect AXI4 NoC manager interfaces on NoC Initiator Intel FPGA IP to memory resources for fabric managers, such as High Bandwidth Memory (HBM2E) Interface Intel Agilex 7 FPGA IP or External Memory Interfaces (EMIF) IP, or to the NoC Clock Control Intel FPGA IP for access to the NoC performance monitors. Do not connect the NoC Initiator Intel FPGA IP to memory resources for the HPS in the External Memory Interfaces for HPS Intel FPGA IP. After connecting AXI4 NoC manager and AXI4 NoC subordinate interfaces, click the Address Map tab in Platform Designer to specify the base address for each connection. If an AXI4 NoC manager interface connects to multiple AXI4 NoC subordinate interfaces, ensure each connection has a unique starting address. You can click the Assign Base Addresses button to allow Platform Designer to assign addresses automatically.
  • If you are using the NoC Assignment Editor connection flow, as NoC Design Flow Options describes, and using Platform Designer to instantiate your NoC IP, leave the AXI4 NoC manager interfaces unconnected in the Platform Designer System View tab. After running Intel® Quartus® Prime Analysis & Elaboration, you use the NoC Assignment Editor to define connectivity and addressing to prepare your design for RTL simulation.
  • If you are using the NoC Assignment Editor connection flow, as NoC Design Flow Options describes, and instantiating your NoC IP directly in RTL, the AXI4 NoC manager interfaces do not exist. After running Intel® Quartus® Prime Analysis & Elaboration, you use the NoC Assignment Editor to define connectivity and addressing to prepare your design for RTL simulation.

For details on the NoC Initiator Intel FPGA IP, refer to NoC Initiator Intel FPGA IP.