How to use spi with rpi-4

[Laurentiu-Cristian Duca]

Dear friends,

   I am trying to test spi on raspberry pi 4.
I have set dtparam=spi=on in config.txt
  After I boot the rpi-4, I enter the following commands:
modprobe spi-bcm2835
modprobe spi-bcm2835-aux
modprobe spidev
  Even so, the /dev/ is not populated with spidev0.0 or spidev0.1 or
spidev1.0 ...

  I have compiled the dtb with the command:
make ARCH=arm64 bcm2711-rpi-4-b.dtb
Also, the kernel is compiled for ARCH=arm64.

  Any ideas on how to have /dev populated?

Thank you very much,
L-C.