For simplicity - you want to use fastboot to boot your OS.
To do that, you must encapsulate your blob into fastboot-compatible image and add fake device tree/ramdisk/cmdline. You can use steps I use for u-boot images:
As for binary - it only needs “proprietary” header like this one:
Default entry address is 0x80080000, SDRAM starts @ 0x80000000; Remember that top of the ram is reserved for TrustZone.