Xavier NX: Connecting PCIe x1 device to PCIe x4 controller

[andy.nicholas]

We are creating a custom carrier board for the Xavier NX and must connect a PCIe x1-lane device to the PCIe x4 port.

Does the PCIe x4 controller will auto-detect the x1 device and there is no issue with not connecting the remaining 3 lanes? Or must the unused lanes from the x4 controller be terminated somehow? Is there a guide documentation?

Thank you.

[omp]

@andy.nicholas

Does the PCIe x4 controller will auto-detect the x1 device and there is no issue with not connecting the remaining 3 lanes?

Yes, x4 controller can be connected to x1 device.

[flavio.plos]

@omp
Linking to that topic: can the x4 controller be connected up to 4 PCIex1 devices ? Is PCIe x 4 bifurcation on single x1 lanes, supported?

[omp]

No, it is not supported.