UTMI_PLL
u2o_clear(base, UTMI_PLL, UTMI_PLL_PLLVDD18_MASK
u2o_set(base, UTMI_PLL, 0xee<<UTMI_PLL_FBDIV_SHIFT
u2o_set(base, UTMI_PLL, VCOCAL_START);
u2o_clear(base, UTMI_PLL, VCOCAL_START);
while ((u2o_get(base, UTMI_PLL) & PLL_READY) == 0) {
u2o_get(base, UTMI_PLL));