ROUNDDOWN
len = ROUNDDOWN(rawlen, DESBLOCK);
len = ROUNDDOWN(min(len, MAXPACKET), DESBLOCK);
vrtc->last_period += ROUNDDOWN(since_last, period_new);
vrtc->last_period += ROUNDDOWN(since_last, period);
ROUNDDOWN(delta, period) + vrtc->base_clock;
ROUNDDOWN(mi_flt_stat[0].mf_err_add, MC_BOUND_BYTE)) &&
ROUNDDOWN(mi_flt_stat[1].mf_err_add, MC_BOUND_BYTE))) {
ROUNDDOWN(mi_flt_stat.mf_err_add, MC_BOUND_BYTE))) {