cscope not working properly for out of module development

I have generated cscope database using the following command in the linux source code present in my home folder.

$ make cscope

I am writing my sample drivers in another folder say ~/LinuxDeviceDrivers

I open my vim file of my sample driver code in ~/LinuxDeviceDrivers and add the cscope connection:

:cs add /home/jamal/linux-5.2.8/cscope.out

When i now search for a particular tag, for example start_kernel

:cs find g start_kernel

It throws an error: File 'init/main.c' not found

Did i miss any step here?