STAT_CTRL
sky2_write32(hw, STAT_CTRL, SC_STAT_CLR_IRQ);
sky2_write32(hw, STAT_CTRL, SC_STAT_RST_SET);
sky2_write32(hw, STAT_CTRL, SC_STAT_RST_CLR);
sky2_write32(hw, STAT_CTRL, SC_STAT_OP_ON);