Ubuntu or Raspbian build instructions

I have BPI-M2+ and i would like to download and recompile linux source including bootloader. I found lots of links on BPI website and i’m completely confused. I would like to build for Ubuntu or Raspbian and my build platform is Ubuntu 20.04 LTS. Questions:

  1. where is toolchain list?
  2. Build instructions or porting guide?

1 Like