### How to add?
I may need to add the spi2 definition for STM32L476.
Where should I add the definition?
You don't need to add it. It exists in dts/arm/st/l4/stm32l471.dtsi
B. nucleo_l476rg.dts> C. <BOARD>.overlay file located in the project directory
I just wonder why there is a definition for SPI2 for the supported board web page, but it is not actually supported by the device tree.
To enable it just add the following in nucleo_l476rg.dts or an overlay file:
status = "okay";