How to use USB OTG Controller's DMA Master


#1

Hi Everyone!
I’m trying to find a way to stream data from the FPGA part of Cyclone V SoC (on Terasic DE10-Nano) to a USB device plugged to the USB OTG port of that board.
The data will first be buffered in SDRAM and then be read by the DMA Master of the USB OTG Controller, and finally send to the USB device.
Here is the path of the data flow:
FPGA --> FPGA-to-SDRAM Interface --> SDRAM --> USB Controller’s DMA Master --> USB Device

My question is: Under Linux, how to enable the USB OTG Controller’s DMA Master to move data from SDRAM to USB Device?