RapidIO Intel FPGA IP User Guide

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

4.2.1. RapidIO IP Core Clocking

The RapidIO IP core has the following clock inputs:
  • sysclk: Avalon® system clock.
  • clk: : reference clock for the transceiver Tx PLL and Rx PLL. In Intel® Arria® 10 and Intel® Cyclone® 10 GX variations, this clock port drives only the Rx PLL.
  • cal_blk_clk: transceiver calibration-block clock (Arria II GX, Arria II GZ, Cyclone IV GX, and Stratix IV GX variations only).
  • reconfig_clk: transceiver reconfiguration interface clock (Arria II GX, Arria II GZ, Cyclone IV GX, and Stratix IV GX variations only).
  • phy_mgmt_clk: transceiver software interface clock ( Arria® V, Arria® V GZ, Cyclone® V, and Stratix® V variations only).
  • tx_bonding_clocks_chN: Intel® Arria® 10 and Intel® Cyclone® 10 GX devices transceiver channel clocks for the transceiver channel that corresponds to RapidIO lane N ( Intel® Arria® 10 and Intel® Cyclone® 10 GX variations only)

In addition, if you turn on Enable transceiver dynamic reconfiguration for your RapidIO Intel® Arria® 10 and Intel® Cyclone® 10 GX variations, the IP core includes a reconfig_clk_chN input clock for each RapidIO lane N . Each reconfig_clk_chN clocks the Intel® Arria® 10 and Intel® Cyclone® 10 GX Native PHY dynamic reconfiguration interface for RapidIO lane N.

The RapidIO IP core supports ±100 ppm reference clock difference and can handle a maximum difference of ±200 ppm between the rxclk and txclk clocks.

The RapidIO IP core provides the following clock outputs from the transceiver:

  • Transceiver receiver clock (recovered clock) (rxgxbclk)
  • Recovered data clock (rxclk). Recovered clock that drives the receiver modules in the Physical layer.
  • Transceiver transmit-side clock (txclk). Main clock for the transmitter modules in the Physical layer.

RapidIO IP core 2x and 4x variations are implemented in the transceiver TX bonded mode. All channels of a 2x or 4x variation, on any supported device, must reside in a single transceiver block.

To support this requirement in Arria II GX, Arria II GZ, Cyclone IV GX, and Stratix IV GX variations, the starting channel number for a 4x variation must be a multiple of four.

When you generate a custom IP core for variations other than Intel® Arria® 10 and Intel® Cyclone® 10 GX, the < variation name >_constraints.tcl script contains the required assignments. When you run the script, the constraints are applied to your project.