A size of 1MB for the FDT/DTB seems reasonable.
+fdtfile:
+
+ Mandatory. the name of the DTB file for the specific board for instance
+ the espressobin v5 board the value is "marvell/armada-3720-espressobin.dtb"
+ while on a clearfog pro it is "armada-388-clearfog-pro.dtb" in the case of
+ a board providing its firmware based DTB this value can be used to override
+ the DTB with a different DTB. fdtfile will automatically be set for you if
+ it matches the format ${soc}-${board}.dtb which covers most 32 bit use cases.
+ AArch64 generally does not match as the Linux kernel put the dtb files under
+ SoC vendor directories.
+
ramdisk_addr_r:
Mandatory. The location in RAM where the initial ramdisk will be loaded to