Build

• features

  • wifi
  • gsm (call in / call out / hangout)
  • egl
  • sound
  • camera
  • BT
  • sensors

• init

  # repo init -u git://github.com/CyanogenMod/android.git -b cm-12.1
  
  # repo sync
  
  # source build/envsetup.sh
  
  # lunch cm_rainbow-eng

• recoveries

  # . build/tools/device/makerecoveries.sh cm_rainbow-eng
  
  # mka bootimage

• full build

  # brunch cm_rainbow-eng

MTK

Few words about mtk related binaries, services and migration peculiarities.

Limitations

Services requires root:

system/core/rootdir/init.rc

• surfaceflinger depends on sched_setscheduler calls, unable to change process priority from 'system' user (default user 'system')

• mediaserver depends on /data/nvram folder access, unable to do voice calls from 'media' user (default user 'media')