Xavier NX USB3 Gen2 device mode

Autonomous Machines Jetson & Embedded Systems Jetson Xavier NX
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1

Hi!

We built a Xavier NX carrier to be used in USB 3 device mode and noticed from the documentation that the module supports USB3,1 Gen2 in host mode but not (yet) in device mode.
I’m guessing that since support is available in host mode it is not a hardware limitation but a software / firmware limitation and was wondering if there is any plan to support 10Gbps bandwidth in device mode as well?

Thanks!
/Luca

1 Like
3

Hi,
For more information, please check product design guide and let us know which USB3 port you connect to run in device mode.
https://developer.nvidia.com/jetson-xavier-nx-product-design-guide-v10

4

Hi Dane!

We followed the product design guide and connected the USBSS lanes to our connector (we are using a USB C connector so they go through a mux) and are using USB0 instead of USB2 for USB2.0 (so we can do recovery over the type C connector).
We already got the USB3.0 device mode to work well and measured a bandwidth over the CDC ECM device of about 2.6Gbps but it would be great to know if it is possible to reach Gen2 speeds.
As a reference this is the output on the host machine (to show that Gen1 is working):

[ 2965.454848] usb 2-5: new SuperSpeed Gen 1 USB device number 2 using xhci_hcd
[ 2965.479411] usb 2-5: New USB device found, idVendor=0955, idProduct=7020, bcdDevice= 0.02
[ 2965.479413] usb 2-5: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 2965.479415] usb 2-5: Product: Linux for Tegra
[ 2965.479416] usb 2-5: Manufacturer: NVIDIA
[ 2965.479417] usb 2-5: SerialNumber: 1421920020933
[ 2965.519524] usbcore: registered new interface driver cdc_acm
[ 2965.534850] cdc_ether 2-5:1.2 usb0: register 'cdc_ether' at usb-0000:02:00.0-5, CDC Ethernet Device, 46:be:68:4f:d9:5e
[ 2965.534893] usbcore: registered new interface driver cdc_ether
[ 2965.541169] cdc_ether 2-5:1.2 enp2s0f0u5i2: renamed from usb0
5

Hi,
We have confirmed it can reach Gen1 speed and cannot reach Gen2 speed.

6

Hi Dane,

I am aware of that (it is mentioned in the documentation) but I was just wondering if it is a hardware limitation of the SoC or if it is something that can be addressed in a future firmware / software update since it seems the 10Gbps transceiver for USB is in place?

Cheers,
/Luca

7

Hi,
It is hardware limitation of the SoC.