IWM_CSR_FH_INT_STATUS
r2 = IWM_READ(sc, IWM_CSR_FH_INT_STATUS);
IWM_WRITE(sc, IWM_CSR_FH_INT_STATUS, IWM_CSR_FH_INT_TX_MASK);
IWM_WRITE(sc, IWM_CSR_FH_INT_STATUS, IWM_CSR_FH_INT_RX_MASK);
IWM_WRITE(sc, IWM_CSR_FH_INT_STATUS, ~0);