QM_REG_DQRR_ITR
*ithresh = qm_in(&portal->p, QM_REG_DQRR_ITR);
dqrr->ithresh = qm_in(portal, QM_REG_DQRR_ITR);
qm_out(portal, QM_REG_DQRR_ITR, ithresh);