[U-Boot] iminfo and zImages

Is it just not possible for the zImages in RAM to be decoded as per the uImages ? If I simply use mkimage to convert the image back as a uImage ( essentially take off the first 64 bytes ? ) then iminfo will display the kernel info The uImage file is only 64 bytes smaller so hasn't

[U-Boot] hardware versions to Kernel

I have an ARM CPU on a board that has 3 optional sub boards plugged into it, all of which have 3 hardware rev bits connected to the CPU Rather than getting the CPU to do mmap type stuff or sys/class/gpio stuff to read those versions in the kernel, is there a way for u-boot to push that