SCRN_RPNT_CTL_1
uint32_t v = p9100_ctl_read_4(sc, SCRN_RPNT_CTL_1);
p9100_ctl_write_4(sc, SCRN_RPNT_CTL_1, v);
return (p9100_ctl_read_4(sc, SCRN_RPNT_CTL_1) & VIDEO_ENABLED) != 0;