HPET_TCNF_INT_ENB
return ((vhpet->timer[n].cap_config & HPET_TCNF_INT_ENB) != 0);
t->caps |= HPET_TCNF_INT_ENB;
t->caps &= ~(HPET_TCNF_INT_ENB | HPET_TCNF_TYPE);
t->caps &= ~(HPET_TCNF_VAL_SET | HPET_TCNF_INT_ENB);