RapidIO Intel FPGA IP User Guide

ID 683884
Date 9/15/2021
Public
Document Table of Contents

4.5.1. Concentrator Register Module

The Concentrator module provides an Avalon® -MM slave interface that accesses all configuration registers in the RapidIO IP core, including the CARs and CSRs. The configuration registers are distributed among the implemented Logical layer modules and the Physical layer module. The following figure shows how the Concentrator module provides access to all the registers, which are implemented in different Logical layer modules. The Concentrator module is automatically included when you include the Transport layer.
Note: Registers in the Doorbell Logical layer module are not accessed through the Concentrator. Instead, they are accessed directly through the Doorbell module's Avalon® -MM slave interface.
Figure 16. Concentrator Module Provides Configuration Register Access

The Concentrator module provides access to the Avalon® -MM slave interface and the RapidIO IP core register set. The interface supports simple reads and writes with variable latency. Accesses are to 32-bit words addressed by a 17-bit wide byte address. When accessed, the lower 2 bits of the address are ignored and assumed to be 0, which aligns the transactions to 4-byte words. The interface supports an interrupt line, sys_mnt_s_irq. When enabled, the following interrupts assert the sys_mnt_s_irq signal:

  • Received port-write
  • I/O read out of bounds
  • I/O write out of bounds
  • Invalid write
  • Invalid write burstcount

A local host can access these registers using one of the following methods:

  • Platform Designer (Standard) interconnect
  • Custom logic

A local host can access the RapidIO registers from a Platform Designer (Standard) system. In this figure, a Nios II processor is part of the Platform Designer (Standard) system and is configured as an Avalon® -MM master that accesses the RapidIO IP core registers through the System Maintenance Avalon® -MM slave. Alternatively, you can implement custom logic to access the RapidIO registers.

Figure 17. Local Host Accesses RapidIO Registers from a Platform Designer (Standard) System

A remote host can access the RapidIO registers by sending MAINTENANCE transactions targeted to this local RapidIO IP core. The Maintenance module processes MAINTENANCE transactions. If the transaction is a read or write, the operation is presented on the Maintenance Avalon® -MM master interface. This interface must be routed to the System Maintenance Avalon® -MM slave interface. This routing can be done with a Platform Designer (Standard) system shown by the routing to the Concentrator's system Maintenance Avalon® -MM slave in the previous figure. If you do not use a Platform Designer (Standard) system, you can create custom logic as shown below.

Figure 18. Custom Logic Accesses RapidIO IP core Registers