AGX Orin UPHY2 Use Options

[LiCC18]

Hi,

I’m designing my custom bord for AGX Orin module. I found the Configuration options for UPHY2 in the Jetson-AGX-Orin_Series-Diaguide_DG-10653-001-v1.6.pdf document. If I don’t use MGBE, can I extend UPHY [5:2] as an NVME PCIe x 4 Lane ?

Thanks！

[WayneWWW]

No, only that PCIe x8.

[LiCC18]

Hi,

Thank you for your quick response.

In DP-10508-002-v1.2, Page 7536, it is described that the PCIe x 8 interface supports PCIe x 4.

What do I need to change if I use UPHY2 instead of MGBE as shown in the following image ? Does this need to change the software？

Thanks!

[WayneWWW]

Hi,

The document is just talking about this controller is able to work in one of the x8, x4, x2, x1 configuration because our controller support downward lanes.

It does not mean “I can use 4 x1 lanes here”.

And yes, you need to configure it from software. Mentioned in this document.

https://docs.nvidia.com/jetson/archives/r35.5.0/DeveloperGuide/HR/JetsonModuleAdaptationAndBringUp/JetsonAgxOrinSeries.html?highlight=agx#enable-pcie-in-a-customer-cvb-design

[LiCC18]

Hi，

There may be some misunderstanding. I would like to use this port as PCIe ×4 instead of PCIe 4 x1 lanes. Can it be used normally under this condition？

Thanks！

[WayneWWW]

As I already told, our controller has downward support. It does not need extra software to support a x4 design from a x8 software configuration.

I mean if your hardware design only has lane 0~3 as a x4 design, we still support it even under the situation that the default software is x8.

What you need to do is refer to above document I posted.