Hello Pedro Correa de Castro,
SDK2.0 is old now, please download the newest KSDK2.2 for TWR-KV31F120M, the download link is :
Welcome to MCUXpresso | MCUXpresso Config Tools
Choose board as TWR-KV31F120M, then click build an sdk, generate the code and download it.
You can find the SPI diriver in folder :
SDK_2.2_TWR-KV31F120M_mcuxpresso\devices\MKV31F51212\drivers

The according sample code in folder: SDK_2.2_TWR-KV31F120M_mcuxpresso\boards\twrkv31f120m\driver_examples\dspi
Wish it helps you!
Have a great day,
Kerry
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