TX2 DTS/DTB with PCIE x4

Robotics & Edge Computing Jetson & Embedded Systems Jetson TX2
1

I had a DTS/DTB issue with the USB2.0 on a custom PCB with TX2. See this post:

https://devtalk.nvidia.com/default/topic/1028223/jetson-tx2/tx2-usb-not-work/post/5277808/#5277808

I am also having an issue with the PCIe connected to a Xilinx Artix 7. I developed my FPGA code using the Xilinx AC701 connected to the TX2 carrier board and that prototype system works well. However the custom PCB with TX2 socketed and the Artix 7 placed on the board does not work. The PCIe does not show up in the lspci and the dmesg shows:

dmesg | grep pcie
[    0.142409] node /plugin-manager/fragment-500-pcie-config match with board >=3310-1000-500
[    0.143141] node /plugin-manager/fragment-500-e3325-pcie match with board >=3310-1000-500
[    0.265588] iommu: Adding device 10003000.pcie-controller to group 50
[    6.111281] tegra-pcie 10003000.pcie-controller: 4x1, 1x1 configuration
[    6.122903] tegra-pcie 10003000.pcie-controller: PCIE: Enable power rails
[    6.132412] tegra-pcie 10003000.pcie-controller: probing port 0, using 4 lanes
[    6.145123] tegra-pcie 10003000.pcie-controller: probing port 2, using 1 lanes
[    6.594197] tegra-pcie 10003000.pcie-controller: link 0 down, retrying
[    7.262219] tegra-pcie 10003000.pcie-controller: link 0 down, retrying
[    7.697787] tegra-pcie 10003000.pcie-controller: link 0 down, retrying
[    7.724253] tegra-pcie 10003000.pcie-controller: link 0 down, ignoring
[    8.140188] tegra-pcie 10003000.pcie-controller: link 2 down, retrying
[    8.554212] tegra-pcie 10003000.pcie-controller: link 2 down, retrying
[    8.970217] tegra-pcie 10003000.pcie-controller: link 2 down, retrying
[    8.978790] tegra-pcie 10003000.pcie-controller: link 2 down, ignoring
[    8.985878] tegra-pcie 10003000.pcie-controller: PCIE: no end points detected
[    8.993274] tegra-pcie 10003000.pcie-controller: PCIE: Disable power rails

Inspection inside the FPGA shows that the TX2 is not providing the PCIe reference clock on the custom PCB. I am wondering if there is another device tree issue with the TX2.

2

FYI, this is the dmesg for the AC701 edge connected to the TX2 carrier board and using the same FPGA program:

dmesg | grep pcie
[    0.142576] node /plugin-manager/fragment-500-pcie-config match with board >=3310-1000-500
[    0.143286] node /plugin-manager/fragment-500-e3325-pcie match with board >=3310-1000-500
[    0.265951] iommu: Adding device 10003000.pcie-controller to group 50
[    6.639866] tegra-pcie 10003000.pcie-controller: 4x1, 1x1 configuration
[    6.649505] tegra-pcie 10003000.pcie-controller: PCIE: Enable power rails
[    6.660783] tegra-pcie 10003000.pcie-controller: probing port 0, using 4 lanes
[    6.672817] tegra-pcie 10003000.pcie-controller: probing port 2, using 1 lanes
[    7.154781] tegra-pcie 10003000.pcie-controller: link 2 down, retrying
[    7.568811] tegra-pcie 10003000.pcie-controller: link 2 down, retrying
[    8.124815] tegra-pcie 10003000.pcie-controller: link 2 down, retrying
[    8.134291] tegra-pcie 10003000.pcie-controller: link 2 down, ignoring
[    8.142087] tegra-pcie 10003000.pcie-controller: PCI host bridge to bus 0000:00
[    8.299775] pcieport 0000:00:01.0: enabling device (0000 -> 0002)
[    8.306887] pcieport 0000:00:01.0: Signaling PME through PCIe PME interrupt
[    8.322665] pcie_pme 0000:00:01.0:pcie01: service driver pcie_pme loaded
[    8.330369] aer 0000:00:01.0:pcie02: service driver aer loaded
[    8.344103] tegra-pcie 10003000.pcie-controller: speed change : Gen-1 -> Gen-2
3

Hello,

Which x4 configuration are you using? Some debug method are listed in this elinux page.
https://elinux.org/Jetson/TX2_USB

You could check /proc/device-tree during runtime and see what is the exact device tree you are using.

4

This issue has been resolved as a board design issue and not anything to do with the TX2.