uenvcmd=if load mmc 0:2 ${loadaddr} /boot/zImage; then setenv mmcdev 0; run uenvboot; else setenv mmcdev 1; setenv mmcroot /dev/mmcblk1p2 rw; if load mmc 1:2 ${loadaddr} /boot/zImage; then run uenvboot; else echo No zImage found; fi; fi
uenvboot=run loadfdt; run setmmcroot; run mmcboot
setmmcroot=setenv mmcroot /dev/mmcblk${mmcdev}p2 rw
loadfdt=load mmc ${mmcdev}:2 ${fdtaddr} /boot/dtbs/${fdtfile}