Template:FriendlyCoreAllwinner-CHIPID

As for Allwinner H2+/H3/H5/ SoCs each of these CPUs has an internal 16-btye CHIP ID which can be read by running the following commands in the Linux-4.14 kernel:

$ apt-get install bsdmainutils
$ hexdump /sys/bus/nvmem/devices/sunxi-sid0/nvmem 
0000000 8082 0447 0064 04c3 3650 ce0a 1e28 2202
0000010 0002 0000 0000 0000 0000 0000 0000 0000
0000020 0000 0000 0000 0000 0000 0000 0000 0000
0000030 0000 0008 0508 0000 0000 0000 0000 0000
0000040 0000 0000 0000 0000 0000 0000 0000 0000

"8082 0447 0064 04c3 3650 ce0a 1e28 2202" is the 16-byte CHIP ID.