SPI Slave for AGX Orin

Robotics & Edge Computing Jetson & Embedded Systems Jetson AGX Orin
1

Hi,
I have tried a loopback test for SPI which worked successfully.

Now i need to set my Orin as slave for communicating with master.

What are the changes i need to do to the device tree file and how to run

The other posts that i have referred were for mainly Xavier NX and there were many suggestions to set for 3210000 or 2600000

Kindly can you give some clarity and suggestions on what to do

Regards
Srivathsan P

3

Hi srivathsan.p,

Are you using the devkit or custom board for AGX Orin?
What’s your Jetpack version in use?

Please just modify the following line in device tree if you want to use spi0 as slave.

        spi@3210000 {
-                compatible = "nvidia,tegra186-spi";
+                compatible = "nvidia,tegra186-spi-slave";
                reg = <0x00 0x3210000 0x00 0x10000>;
4

Jetson AGX Orin 64Gb devkit
Jetpack 5.1.2

5

Which file do i need to change?

Changing this and post flash running the spidev_test for slave program as spidev0.0 will be sufficient right?

Regards
Srivathsan P

6

The DTB from your board (/boot/dtb/kernel_XXX.dtb). Please decompile it and modify the line I shared above.

7

I converted the dtb to the dts and then did changes as per the line shared
but i got duplicate entry so i kept only the spi-slave line and removed the other comaptible line and converted it back to dtb and replaced the file at /boot/dtb/.
then after restart when i tried dmesg | grep spi
i got

spi-tegra114 3210000.spi: Adding to iommu group 0
spi-tegra114 3210000.spi: Adding to iommu group 0

8

There is no update from you for a period, assuming this is not an issue any more.
Hence we are closing this topic. If need further support, please open a new one.
Thanks

Can you share the device tree file and also the full dmesg for further check?