Advice on Yocto Build for Mainline Linux or for NXP Linux for Polyhex Debix Model A or Model A SoM for Open Source Wildlife Camera System

Hi,

I was wondering if anyone had any advice on the simplest way for me to 
use Yocto to build an image using mainline Linux or NXP Linux for the 
Polyhex Debix Model A i.MX M8 Plus board or for the Debix SoM A i.MX 8M 
Plus board with SoM A I/O board?

For my work in conservation of endangered European dormouse species I'm 
working on a new open source wildlife camera system so I'll have to 
learn how to include kernel drivers for image sensors in the device 
tree. I'm not a professional kernel driver engineer so if anyone can 
recommend anything that I could study to help with this it would also be 
very valuable.

We're looking at the i.MX 8M Plus because of it's very strong ISP (Image 
Signal Processor), two MIPI CSI-2 ports and NXP's strong commitment to 
open source. The Polyhex Debix boards seem to provide a good way for us 
to test prototypes in the field before designing our own carrier board 
for an i.MX 8M Plus SoM.

As far as I can work out, the Polyhex Debix boards stay fairly close to 
the design of the two official NXP evaluation boards 8MPLUSLPD4-EVK and 
8MPLUSLPD4-PEVK:

https://www.nxp.com/design/design-center/development-boards-and-designs/8MPLUSLPD4-EVK

https://www.nxp.com/design/design-center/development-boards-and-designs/8MPLUSLPD4-PEVK

I was able to find these Yocto DTS and DTSI files for the boards:

for Debix Model A SBC
https://git.yoctoproject.org/linux-yocto-dev/plain/arch/arm64/boot/dts/freescale/imx8mp-debix-model-a.dts
for Debix Model A SoM I/O Board
https://git.yoctoproject.org/linux-yocto-dev/plain/arch/arm64/boot/dts/freescale/imx8mp-debix-som-a-bmb-08.dts
and DTSI for Debix Model A SoM
https://git.yoctoproject.org/linux-yocto-dev/plain/arch/arm64/boot/dts/freescale/imx8mp-debix-som-a.dtsi

Searching for the i.MX 8M Plus under OpenEmbedded I could only find DDR4 
and LPDDR4 boards (of which I think only the LPDDR4 board is in use):

https://git.yoctoproject.org/meta-freescale/tree/conf/machine/imx8mp-ddr4-evk.conf?h=master

https://git.yoctoproject.org/meta-freescale/tree/conf/machine/imx8mp-lpddr4-evk.conf?h=master

these both build on imx8mp-evk.inc

require include/imx8mp-evk.inc

which I think is the official i.MX 8M Plus evaluation board.

Debix give some guidance on using Yocto to build images for their boards 
here https://github.com/debix-tech/uboot but I thought that it would be 
better for me to take a cleaner approach.

Thank you very much for your help,

Will