I got the littlevgl library and its demo program running on an inexpensive HiLetgo (Amazon) resistive touch LCD Module connected to both a BBB and Pocketbeagle. It uses the fb and touchscreen drivers built into the debian distributions. The cool thing about using the linux touchscreen driver is that you can use tslib to provide calibration services for the resistive touchscreen (which is usually a pain).
I’m sharing it here in case anyone wants to have a GUI with their project without having to run the entire X11/window manager stack. You can use the /dev/fb0 and /dev/input/event2 device files directly or use littlevgl to provide GUI and graphics functions.
The main thing are the device tree files. There are also a couple of simple files to configure littlelvgl.
Pocketbeagle info (most detailed): https://github.com/danjulio/lepton/tree/master/pocketbeagle/littlevgl_demo
Beaglebone black info: https://github.com/danjulio/lepton/tree/master/beaglebone/littlevgl_devicetree
I hope this is helpful to y’all. Hit me up with any questions (or issues you find).