Hi Kumar,
Which mode of MCG module works in? Just use MCG works in PEE as an example, Kinetis 100MHz product could run core clock frequency up to 100MHz and Flexbus clock frequency up to 50MHz. When MCG module output clock at 100MHz, the System Clock Divider Register 1 (SIM_CLKDIV1) [OUTDIV3] bits set value to 0b11, which is 1/4 of MCG output clock frequency (25MHz). If you want to run Flexbus at 30MHz, the MCG output clock need to be 90MHz/60MHz/30MHz. And you need to set (SIM_CLKDIV1) [OUTDIV3] bits value to 0b10/0b01/0b00.
Wish it helps.
Best regards,
Ma Hui