NETC_CBDRCIR_INDEX
cbdr->next_to_clean = netc_read(cbdr->regs.cir) & NETC_CBDRCIR_INDEX;
while ((netc_read(cbdr->regs.cir) & NETC_CBDRCIR_INDEX) != i) {
(val & NETC_CBDRCIR_INDEX) == i,