ref: 52a367f3ea8b6fa256b2a9b0e52c5c2d557a9fc3 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)