I managed to do USB working.
Thanks, user @zoenggit for the tip.
Found a hand-made ham radio transceiver project from one guru guy, it has a proper implementation of EHCI/OHCI stack for Allwinner D1/T113 hftrx_tinyusb. I just changed it a little to support RT-Thread.
Now USB keyboard sends a key press to the system.
HID device address = 2, instance = 0 is mounted HID Interface Protocol = None HID has 4 reports msh /> H e l l o !