Hi Sahil,
Thanks for your support.
As in our discussion we tried the method of replacing the “u-boot.img” file to the Toradex default reference image (BSP-5) and boot from the pendrive. It was working well as per the expectation. Since, we customised the full boot partition with custom device tree changes which needs to flash the full package not only replacing the “u-boot.img” file. The earlier attached zip file contains the full package for boot partition.
I tried different method to solve the problem by replacing the file one-by-one to the Toradex default reference image in yocto bsp-5. It is working well when I replaced all the files from the custom boot package which can boot into Tezi through pendrive by executing the command “run bootcmd_usb0” in u-boot screen except “u-boot-initial-env-spl” file. I checked the environmental variables and found that the “fdtfile” variable are pointing customised “dtb” file. When I changed the value of this variable to default dtb file, this works for me.
The problem got solved.