From:
http://developer.sonymobile.com/2016/02/17/work-on-the-mainline-kernel-for-open-xperia-devices/
http://developer.sonymobile.com/2016/02/17/work-on-the-mainline-kernel-for-open-xperia-devices/
We’ve just released new build guides on how to build Linux mainline kernel for Xperia devices and how to build a minimal version of Linux for Xperia devices. With these assets, you can experiment with IoT prototyping, or join the development of support for Xperia devices in the Linux kernel. Learn about this, and find out how the Open Device program got its start after the jump.