read_lcb_csr
ret = read_lcb_csr(dd, csr, &data);
ret = read_lcb_csr(dd, lcb_cache[i].off, &val);
int read_lcb_csr(struct hfi1_devdata *dd, u32 offset, u64 *data);
if (read_lcb_csr(dd, csr_off, (u64 *)&data))
if (read_lcb_csr(dd, DC_LCB_STS_ROUND_TRIP_LTP_CNT, ®))