SPI CS doesn't work

Hi,
The pins may not work properly if you configure them as SPI pins and GPIO pins at the same time. Could you also try to set the properties:

nvidia,cs-setup-clk-count
nvidia,cs-hold-clk-count
nvidia,cs-inactive-cycles
nvidia,clk-delay-between-packets

And check if you can see signals in CS0 and SCK pins when communicating with the IMU sensor.

If there is still no signals, please connect miso and mosi and then run

$ ./spidev_test -D /dev/spidev0.0 -v

You have confirmed this test works. Please check if there is signals in CS0 and SCK pins in the test.