Configuration via Protocol (CvP) Implementation User Guide: Agilex™ 5 FPGAs and SoCs

ID 813775
Date 10/02/2024
Public

2.2.1. CvP Initialization Mode

In this mode, an external configuration device stores the periphery image and it loads into the FPGA through the following configuration schemes:
  • Active Serial (AS) normal and fast modes
  • AVST x8
  • JTAG
The 120 ms PCIe* link up time requirement can only be met by using Active Serial x4 fast mode configuration scheme. The host memory stores the core image and it loads into the FPGA through the PCIe* link. The PCIe* REFCLK needs to be running prior to sending the periphery image.

To configure the periphery image while meeting the 120 ms of power stable to PCIe* link active time, you must specify the OSC_CLK_1 pin as 25 MHz, 100 MHz, or 125 MHz, and set the AS_CLK clock to 166 MHz.

After the periphery image configuration is complete, the CONF_DONE signal goes high and the FPGA starts PCIe* link training. When PCIe* link training is complete, the PCIe* link transitions to L0 state and then allows the host to complete PCIe* enumeration of the link. The PCIe* host then initiates the core image configuration through the PCIe* link.

After the core image configuration is complete, the CVP_CONFDONE pin (if enabled) goes high, indicating the FPGA is fully configured.

After the FPGA is fully configured, the FPGA enters user mode. If the INIT_DONE signal is enabled, the INIT_DONE signal goes high after initialization is complete and the FPGA enters user mode.

In user mode, the PCIe* links are available for normal PCIe* applications.