Colibri VF61 boot hang

I am using Colibri VF61 V1.1B board and trying to boot it from sd card.
U-boot is in NAND flash,kernel and rootfs in sd card.
I have downloaded the kernel from toradex gti branch toradex_vf_3.18.
U-boot version 2014.10
toolchain used is from yocto build for VF61.
Copied the zImage in rootfs/boot directory,U-boot loads kenel image and dtb from sd card but hangs after
Starting kernel …

Colibri VFxx # run sdboot
Booting from MMC/SD card...
4488624 bytes read in 315 ms (13.6 MiB/s)
26611 bytes read in 97 ms (267.6 KiB/s)
Kernel image @ 0x82000000 [ 0x000000 - 0x447db0 ]
## Flattened Device Tree blob at 84000000
   Booting using the fdt blob at 0x84000000
   Loading Device Tree to 8fd12000, end 8fd1b7f2 ... OK

Starting kernel ...

But if i copy zImage from NAND flash to sdcard it works.

Note that the 3.18 kernel for Vybrid is quite old and we do not support it anymore and the same applies for 2014.10 Yocto.

The current applicable kernel version for Vybrid is 4.4.39 in toradex_vf_4.4 branch and v2016.12 for Yocto. See OpenEmbedded article along with Build U-Boot and Linux Kernel from Source Code article.

Please note that sdboot is deprecated and distro boot the way to go.

Thank you.
Updating the u-boot to latest version 2016.11 worked.We will use the latest kernel for development as well.
Current yocto is 2015.12, is there anyway to update it to from 2015.11 or complete yocto rebuild is required?

Our layers provide U-Boot 2016.11 only in the morty branches (used by the latest V2.7 BSP version), which makes use of OpenEmbedded morty/Angstrom 2016.12. So generally yes, you would have to rebuild with the latest version.