ref: ae61eb9381f6b0c70e1c52bf2c2b7f4cd0b5bb6f 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)