building.md

Building lk2nd

Requirements

• ARM (32 bit) GCC tool chain
  • Arch Linux: arm-none-eabi-gcc
  • Alpine Linux and postmarketOS: gcc-arm-none-eabi
  • Debian and Ubuntu: gcc-arm-none-eabi
  • Fedora: arm-none-eabi-gcc-cs
• Device Tree Compiler
  • Arch Linux: dtc
  • Alpine Linux and postmarketOS: dtc
  • Debian and Ubuntu: device-tree-compiler
  • Fedora: dtc
• libfdt
  • Alpine Linux and postmarketOS: dtc-dev
  • Debian and Ubuntu: libfdt-dev
  • Fedora: libfdt-devel
• GNU tar
  • Alpine Linux and postmarketOS: tar

Building lk2nd

Check targets.md for the make target you should use below. (It depends on the SoC of your device.)

$ make TOOLCHAIN_PREFIX=arm-none-eabi- lk2nd-msmXXXX

Replace TOOLCHAIN_PREFIX with the path to your tool chain. lk2nd.img is built and placed into build-lk2nd-msmXXXX/lk2nd.img.

Building lk1st

Note: Unlike lk2nd, lk1st is still experimental and therefore not described here yet.

Additional build flags

lk2nd build system provides few additional compile time settings that you can add to the make cmdline to enable some additional features.

General settings

DEBUG= - Log level

Set to 0 to suppress most of the logging, set to 2 to enable excessive log messages (may slow down boot). Default is 1.

DEBUG_FBCON= - Enable logging to the display

Set to 1 to make lk2nd print the logs on the screen.

LK2ND_VERSION= - Override lk2nd version string

By default lk2nd build system will try to get the version from git. If you need to override the version (i.e. if you want to package lk2nd build), set this varable.

lk2nd specific

LK2ND_ADTBS=, LK2ND_QCDTBS=, LK2ND_DTBS= - Only build listed dtbs

lk1st specific

LK2ND_COMPATIBLE= - Board compatible

Set the board compatible value.

LK2ND_BUNDLE_DTB= - Board dtb file

Use this dtb for lk1st build.

LK2ND_DISPLAY= - Display panel driver

Set specific panel driver. By default it uses cont-splash.