Hello,
Regarding original YP, i.MX7 machine for jethro (or later)
seems to be already supported in freescale BSP.
https://github.com/Freescale/meta-fsl-arm/tree/jethro/conf/machine
In meta-debian, currently no support for i.MX7 because no hardware.
To make it available, the BSP needs to be ported to meta-debian.
Regards,
Kazuhiro