PWR_CTRL2
ctrl = smtpmic_reg_read(sc, PWR_CTRL2);
smtpmic_reg_write(sc, PWR_CTRL2, ctrl | PWR_CTRL2_SW_RST);
ctrl = smtpmic_reg_read(sc, PWR_CTRL2);
smtpmic_reg_write(sc, PWR_CTRL2, ctrl | PWR_CTRL2_SW_SD);