device tree on rpi2 not working

[Tim Sander]

Hi

I have already asked a similar question in the raspberry pi forum without an 
answer so i figured that my question might be a bit to deeply technical for 
the forums. Besides i am pretty exited about the work on the free graphics 
driver and would really like to integrate that as time permits later on.

As a hobby project i have put some effort into putting a ptxdist based linux 
distro for the rpi2 into shape. It allows developing with qt, opencv, 3d 
accleration (old style) and camera drivers. The repository is at:
https://gitlab.com/k6devel/ptxdist-raspberry-pi

But when trying to integrate the pwm drivers i noticed that device tree is 
somehow not working with my solution. Thats where i am stuck and i have no 
idea whats wrong? I would be really happy if someone could give me a clue.

Thats what i have been trying out so far:
I have been using the kernel from 
https://github.com/raspberrypi/linux.git branch rpi-4.1.y
829528571fdcfe078fb165c4acd3b585e8e24a99

I extracted a kernel config from a running raspian and got the /proc/config.gz 
and used this for building the kernel. It boots and all but there is no 
/proc/device-tree link as with raspbian and device tree overlays are not 
working either. I know with high confidence by exchaning my kernel on a 
raspbian installation that with my kernel the device tree initialization fails 
even on raspbian. So i figure its most likely a kernel problem. But then the 
kernel seems to have the device tree patches and my config is pretty close...

I also tried to find the original raspbian kernel but even so its running a 
4.1 kernel an apt-source get linux-image only turned up older 3.x kernels and 
i could not find any sources in the raspbian repositories which is strange.

It seems to me also that the pwm driver which i am after is also just fully 
enabled by patches which have been seen on this list recently.  And against 
what kernel tree are all these patches?

Best regards
Tim