STAT_CTRL
CSR_WRITE_4(sc, STAT_CTRL, SC_STAT_RST_SET);
CSR_WRITE_4(sc, STAT_CTRL, SC_STAT_RST_CLR);
CSR_WRITE_4(sc, STAT_CTRL, SC_STAT_OP_ON);
CSR_WRITE_4(sc, STAT_CTRL, SC_STAT_CLR_IRQ);