Updated the CuBox-i4 Pro to Kernel 3.18, and now use the complete ‘device tree’ zImage and dtb boot method:

The source can be found here:  https://github.com/jmontleon/fedora-20-cubox-i_hb/tree/3.18.0

– and the u-boot boot commands are:

setenv bootargs "root=/dev/mmcblk0p3 rootfstype=ext4 rootwait console=ttymxc0,115200n8 console=tty1 video=mxcfb0:dev=hdmi,1920x1080M@60,if=RGB24,bpp=32"
setenv bootcmd "load mmc 0:1 0x10800000 zImage; load mmc 0:1 0x18000000 imx6q-cubox-i.dtb; bootz 0x10800000 - 0x18000000"
boot

Fedora release 21 (Twenty One)
Kernel 3.18.0 on an armv7l (ttymxc0)
.............
# uname -a
Linux rgcubox 3.18.0 #1 SMP PREEMPT Wed Dec 10 20:32:22 EST 2014 armv7l armv7l armv7l GNU/Linux

Robert Gadsdon.   December 11, 2014.