FXP_CSR_SCB_STATACK
statack = CSR_READ_1(sc, FXP_CSR_SCB_STATACK);
CSR_WRITE_1(sc, FXP_CSR_SCB_STATACK, statack);
while ((statack = CSR_READ_1(sc, FXP_CSR_SCB_STATACK)) != 0) {
CSR_WRITE_1(sc, FXP_CSR_SCB_STATACK, statack);