How can I enable HPS-to-FPGA bridges in U-boot for Arria 10 SOC devices?

The HPS to FPGA bridge and Lightweight HPS-to-FPGA bridge can be enabled from U-boot. Before the bridges are enabled, the FPGA portion must enter user mode by loading the core configuration file. U-boot for Arria 10 SOC generated from SOC EDS 16.1 and later contain commands to load FPGA core configuration and enable HPS to FPGA bridges.

To enable the HPS-to-FPGA bridges from U-Boot follow the steps below to enter commands in U-boot command prompt:

• Depending on boot source, run the appropriate command to load FPGA core configuration file:
  • SD: run core_rbf_prog
  • QSPI: run qspirbfcore_rbf_prog
  • NAND: run nandrbfcore_rbf_prog
• Run the fpgabr command to enable the HPS-to-FPGA bridges, as follows: fpgabr 1