OPAL_RTC_READ
rv = opal_call(OPAL_RTC_READ, vtophys(&junk), vtophys(&junk));
rv = opal_call(OPAL_RTC_READ, vtophys(&junk), vtophys(&junk));
rv = opal_call(OPAL_RTC_READ, vtophys(&ymd), vtophys(&hmsm));
rv = opal_call(OPAL_RTC_READ, vtophys(&ymd), vtophys(&hmsm));