SPE: aon_echo : Permission Denied

I followed the Jetson Sensor Processing Engine (SPE) Developer Guide (r36.3 Release) and flashed the SPE firmware successfully. Then to test the IVC App, I made the necessary changes/additions to the Linux_for_Tegra/source/hardware/nvidia/t23x/nv-public/nv-platform/tegra234-p3737-0000+p3701-xxxx-nv-common.dtsi file and recompiled it and flashed the whole device as instructed.

When i run $ sudo su -c ‘echo tegra > /sys/devices/platform/bus@0/bus@0:aon_echo/data_channel’, i am getting Permission denied .
Please guide me on this.

Thanks in advance!

Hello, arun.kumar.belamge:
Default BSP does not enable AON echo channel.
You can do the following:

  1. Re-build the OOT (Kernel Customization — NVIDIA Jetson Linux Developer Guide 1 documentation)
  2. In device side, install two modules.
  3. Update the kernel DTB as you’ve done.
  4. Re-build the SPE firmware in spe-freertos-bsp.tbz2
  5. Re-flash the device with above changes.

Then you can test AON IVC.
root@tegra-ubuntu:/sys/devices/platform/bus@0/bus@0:aon_echo# echo test >data_channel
root@tegra-ubuntu:/sys/devices/platform/bus@0/bus@0:aon_echo# cat data_channel
root@tegra-ubuntu:/sys/devices/platform/bus@0/bus@0:aon_echo# echo tegra >data_channel
root@tegra-ubuntu:/sys/devices/platform/bus@0/bus@0:aon_echo# cat data_channel


Hi ChenJian.

Thank you for the prompt reply.
I will test this and let you know.

Best Regards

Can you please elaborate the Step 2?
Where and how to install the two modules?

I have already re-built the kernel and got the two modules at : Linux_for_Tegra/source/kernel_out/nvidia-oot/drivers/platform/tegra/aon/

Hello, abelamge:
I don’t get your point.
Those two modules are in kernel_oot_modules_src.tbz2. Just follow the instructions in (Kernel Customization — NVIDIA Jetson Linux Developer Guide 1 documentation ) for OOT building.
It should be located at


Hello ChenJian.
This works, thank you for the support!
It would be good if installing the tegra234-aon.ko and tegra-aon-ivc-echo.ko modules is given as a step in the Jetson Sensor Processing Engine (SPE) Developer Guide.


Hello, abelamge:
Thanks for pointing out that.
We have checked internally and module installation issue is fixed. And the two modules involved will be included in future release.

Just for your information.


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