We are working on a i.MX7 product. We noticed that the PCIe hardware has a 100M clock generator in Sabre board. Is it a must? Could we use the processor internal pll instead? We did not add this clcok gen at our i.MX6 product. We could work fine by using the internal pll in our i.MX6 product. We would like to know if this clock gen is a must. Thanks.