ref: 5f0c2fbc958267e0ddbe21b1199c1f7c1651fb0e
dir: /sys/src/boot/reform/boot.txt/
mw.b 0x40010000 0x0 0x10000
load ${devtype} ${devnum}:${bootpart} 0x40010000 ${prefix}plan9.ini
load ${devtype} ${devnum}:${bootpart} 0x40100000 ${prefix}9reform.u && bootm 0x40100000