ref: 361b65e4df0b4a3562a6e57b0f7b8009c59c3f2b dir: /sys/src/9/bcm64/init9.s/
TEXT main(SB), 1, $8 MOV $setSB(SB), R28 /* load the SB */ MOV $boot(SB), R0 B startboot(SB)