HW_SSP_CTRL0_CLKGATE
SSP_WR(sc, HW_SSP_CTRL0_CLR, HW_SSP_CTRL0_CLKGATE);
while (!(SSP_RD(sc, HW_SSP_CTRL0) & HW_SSP_CTRL0_CLKGATE))
SSP_WR(sc, HW_SSP_CTRL0_CLR, HW_SSP_CTRL0_CLKGATE);
while (SSP_RD(sc, HW_SSP_CTRL0) & HW_SSP_CTRL0_CLKGATE)