I keep getting a delay of 20us - 50us, when the SS is set low, to the clock and data transfer begins on the SPI ports on the imx6ul. I run a linux system on the chip with kernel version 4.9. There does not seem to be any correlation between the frequency and and the delay. Is there somewhere in the SPI driver, that I can change the parameter so this does not happen?
See pictures for clarification, the blue is the SS pin, the yellow is CLK and purple is MOSI.