SSD "forwarding" to host PC?

Robotics & Edge Computing Jetson & Embedded Systems Jetson Orin NX
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Hi,

I would like have following setup. USB0 and USBSS are routed to the same USB-C Connector.
The USB-C connector will be part of a custom carrier board for the Jetson Orin NX.
The Jetson will be powered by the carrier board. On the carrier board, a NVME SSD is connected to the Jetson on PCIe.

If the USB-C is then connected to a host PC, the Orin NX should then come up as two devices.
One should be the USB0 in dev mode as Ethernet connection.
The other should be the NVMe as external drive via the USBSS connection.

The questions:

  • How is the device tree setup?
  • Can there be some device tree setup so that the SSD is “forwared” to that USBSS connection?
  • Is the USBSS then setup as DRP, DFP or UFP on the schematic design?

I hope you can help me in understanding if this is a possible setup.

Thanks.

1 Like
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This setup does not conform to the USB Specification. You cannot split the legay part and the SuperSpeed part into different connections. No operating system will support this.

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Hi, thanks for you answer.

Why not? As far as I understand, usb2.0(HS) and usb3.0(SS) are two independent interfaces. So the host PC also should have two independent interfaces connected to it’s usb-c port (Or usb-A 3.0 for that matter).
In other words, if i connect, let’s say a USB2 thumbdrive to a usb-A 3.0 interface (hardware) on my PC, it will be conencted to a USB2.0 driver. If i do the same with a 3.0 thumbdrive, it connects to the USB3.0 driver.

Am i wrong in this assumption? I mean it would be a really slick way of connecting devices. Also, if i remember correctly, i had devices connected to my PC that did exactly that.

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Ok I did some research and found the following:

It states what you mentioned. Technically it can be possible if you’re in control of the host’s USB stack, which isn’t the case with a PC. Therefore you’re right.

I will resort to using two seperate USB-C.

However, that still poses the question if the SSD bridging is still possible via the USBSS interface??

edit: Typo

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You could provide USB Mass Storage, but that storage is exclusively bound to the USB device as long as its connected. You can’t share a volume on a block level as any file systems would be corrupted.

The other way is USB MTP (Media Transfer Protocol), which is file-based.

The third way would be using SMB or NFS via network. via USB CDC-ECM or RNDIS. You won’t need connection splitting then.

These are your options. Choose one.

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