Significant differences between tegra194-p2888-0001-p2822-0000-maxn-dtb and base dtb in 32.1

So it’s known that to use MaxN Mode on the Xavier you need to flash the customized dtb. However when inspecting the changes between the base dtb and the maxn dtb, I noticed significant changes across the file when analyzing it as a dts. These changes were far more than what was observed in the 31.1 dtb files as noted in

I also double checked the 31.1 dtb’s, and surely enough, the 31.1 dtb only had the thermal range change. 32.1 has far more, mostly what looks like reenumerations of ID’s, but a number of additions.

Namely I noticed portions of the dts where it seemed like the CSI camera lanes were marked as disabled for some reason. Is there some sort of summary for these changes, and what their impacts are? I tried looking for hints in the 32.1 changelog but none noted any changes regarding MaxN.


I think you can check sources to find what the different for the base and manx mode. tegra194-p2888-0001-p2822-0000.dts is the base mode main file, and tegra194-p2888-0001-p2822-0000-maxn.dts is for the maxn.

Okay, I gathered the source files mentioned, and I still have the same questions as before:

Base DTS:

#include "common/tegra194-p2888-0001-p2822-0000-common.dtsi"
#include "common/tegra194-p2822-camera-modules.dtsi"
#include "t19x-common-modules/tegra194-camera-plugin-manager.dtsi"


#include "common/tegra194-p2888-0001-p2822-0000-common.dtsi"
#include "t19x-common-platforms/tegra194-thermal-maxn.dtsi"

The MaxN DTS is missing the camera-modules.dtsi include and tegra camera plugin manager dtsi. Is there a reason for this?

I also noticed the copyright dates on the two files were different; the Base DTS had 2019, where the MaxN had 2018. This is leading me to think that the MaxN wasn’t updated either accidentally or purposefully.

I ask because we are planning on using the Xavier explicitally for image processing work and we plan on using CSI interfaces. Previously on the TX2 we ran it in MaxN mode with the CSI cameras no problem, but this suggests we may have issues on the Xavier.

Is there any information suggesting that MaxN in 32.1 is not compatible with interfacing with CSI camera modules?

I think you can base on the maxn to add the camera module by include your camera module dts file.

So does that imply that MaxN does not come with camera module support in 32.1 (as shipped in the released toolchain)? And if I wish to have camera support, I need to build a modified .dtb with the camera modules included?

I don’t have much experience at this level of hardware development so I apologize if these questions seem naive.

Yes, for this release you need to build your dtb for it.
Otherwise try to run the jetson_clock to boost the performance to check if it can match your request.

Does anyone have measuered the performance boost of using the maxn-conf for flashing compared to the normal config?
Will the Xavier have more performance than using MAXN-Nvpmodel and jetson_clocks?