For zynqmp qspi, frequencies up to 40MHz will work irrespective of feedback clock enabled or disabled. If we want higher than 40Mhz the feedback clock should be enabled. With spi-max-frequency 108MHz it is not working when the feedback clock is disabled. Change it to 40MHz so that it works irrespective of feedback clock enabled or disabled. Signed-off-by: T Karthik Reddy <t.karthik.reddy@xilinx.com> Acked-by: Ashok Reddy Soma <ashok.reddy.soma@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com>