Angstrom Linux FPGA configuration

Hello I have Socrates Cyclone5 Board
My goal to configure FPGA from different rbf files without rebooting if possible.

I have compiled Linux by me and have pre-compiled
Angstrom v2018.12 - Kernel 5.2.0-rc3-00037-g156c059 taken from SoCEDS 18.0.0614

I have found that approach with following commands fail because my distribution don’t know configfs file system.

mkdir /config
mount -t configfs configfs /config
mkdir /config/device-tree/overlays/test

Also it strange that i cannot read status of FPGA status like below
root@cyclone5:~# cat /sys/class/fpga_manager/fpga0/
device/ name of_node/ power/ state status subsystem/ uevent
root@cyclone5:~# cat /sys/class/fpga_manager/fpga0/status
cat: read error: No such file or directory

but I can read state
root@cyclone5:~# cat /sys/class/fpga_manager/fpga0/state
power off

Unfortunately I still didn’t found updated tutorial or documentation how to deal with new version of Kernel.