The pcie lane reversal

Autonomous Machines Jetson & Embedded Systems Jetson Orin NX
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1

hello,

I made a mistake when designing a custom carrier board. Connect the pcie tx/rx cable directly to the tx/rx cable of the device as following.

PCIE2_RX0_P <----------> UPE_RX0_P
PCIE2_RX0_N <----------> UPE_RX0_N
PCIE2_TX0_P <----------> UPE_TX0_P
PCIE2_TX0_N <----------> UPE_TX0_N

But devices need to cross connect tx/rx.

PCIE2_RX0_P <----------> UPE_TX0_P
PCIE2_RX0_N <----------> UPE_TX0_N
PCIE2_TX0_P <----------> UPE_RX0_P
PCIE2_TX0_N <----------> UPE_RX0_N

Can I fix the bug by modifying the Jetson Linux software?

3

Lane reversal is by default supported. No need extra software configuration.

4

hi,

I want to know if Orin NX supports PCIE lane tx rx automatic cross connect.

5

No, not supported.

6

How to understand lane reversal? Does this mean that lane 0 can be connected to laneX(X=0, 1, 2 …) in the case of pcie multi-channel?

8

Yours are not reversal lane setting. TX/RX of RP should be connected to RX/TX of EP. You should change your design.