Arria10 cold reset not working

I am trying to cold reboot arria10 so that fpga combined rbf image can be re loaded from flash with latest image. Writing a ‘1’ to address 0xFFD0500C is not causing a cold reset. Arria10 does reset, but the fpga combined image does not get reloaded. It seems that it behaves just like a warm reset. Do you have a solution for it? and why cold reset is not working as described .