Running Hexagon on SD820 kernel 4.14

I am trying to run Hexagon and SNPE on SD820 with

I followed the procedure in the following link and enabled fastrpc in configs. Please note that i am currently not using the 5.x kernel branch that is mentioned in the link.

adsp seems to be running.
linaro@linaro-alip:~$ cat /sys/devices/platform/adsp-pil/remoteproc/remoteproc0/state

I tried to start the remote dsp.
linaro@linaro-alip:~$ sudo sh -c ‘echo start > /sys/devices/platform/adsp-pil/remoteproc/remoteproc0/state’
sh: 1: echo: echo: I/O error

But could not retrieve serial num.
linaro@linaro-alip:~/dev$ ./getserial
./getserial: /usr/lib/aarch64-linux-gnu/ no version information available (required by ./getserial)

The kernel version:-
linaro@linaro-alip:~/dev$ uname -r

Has anyone tried on this kernel version and got it to work?

Best Regards,