zimage image format

About

For now use only two parts
  1. kernel
  2. rootfs

zimage format do not limiting kernel or rootfs format.

It is just two files in one, like cat file1 file2 > newfile do.

On preferred thing, to round up kernel size to flash block size.

For example, if we have CFI flash with 64K blocks and kernel size
1234567(0x0012d687) then we need to pad it with zero's to size
1245184(0x00130000).

Hint: as You can see hexadecimal looks pretty for such situations :)

So zimage is:

kernel
zero padding to rounded up by ${FLASH_BLOCK_SIZE} kernel
rootfs