TQMa91xxCA - YOCTO Linux BSP documentation

LVDS

Choose a Device Tree Overlay in U-Boot

TQ offers an optional LVDS Display kit for the STKa91xxCA. Each Display can be used on its own by using the corresponding device tree. To allow reuse, the support for each display is separated in a .dtsi fragment.
To enable display support, select the corresponding device tree overlay from the U-Boot boot menu:

  1. Connect the display to the Starterkit.
  2. Power on the board and let the U-Boot countdown expire. Alternatively, type boot when in U-Boot.
  3. When prompted, type the number of the device tree that matches the connected display. Press Enter.
All boot configurations can be found in /boot/extlinux/extlinux.conf.

Select Device Tree Permanently

To set a device tree overlay permanently, edit the /boot/extlinux/extlinux.conf and set the desired device tree in line 4: 

# e.g. to select Tianma TM070JVHG33, edit the line to
DEFAULT lvds-tm070jvhg33

Save and reboot. The overlay with the label lvds-tm070jvhg33 will now be booted per default.