How to change THS-ZERO and THS-PREPARE for mipi-dsi on iMX.8MMini?

[Eric1994]

We are using iMX8M Mini , and bsp is imx-yocto-L4.14.98;

Now we using the fsl-imx8mm-evk.dts to enable mipi panel, where can we change the THE-ZERO and THE-PREPARE time, we can't find them in the device tree or drivers.