Take a look at helio X10

[madushan1000]

If you Google around a bit, you'll be able to find a leaked version of Helio x10 SOC baseband and kernel (if you didn't know already). I'm currently trying to purchase a device(redmi note 2/3 Chinese version or HTC one x9) with this SOC to try and find out what I can do to run code on it. I think this source will help greatly with your reverse engineering effort.

[madushan1000]

Hi,
I downloaded the Android 8 source provided by the vendor for the IOT board and have been looking at it. (took me forever to download, it's around 20GB :/)
It looks like at least some of the modem source code or at least the modem interface source code is included. (there are a lot of compiled code too, I'm going trough the build script to figure out of they are just provided as blobs) Also, some of the tooling required to build them seems to be included.

[valerierx]

nice