Jetson AGX Xavier PCIe J6 Link Error

Autonomous Machines Jetson & Embedded Systems Jetson AGX Xavier
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I have tested the OEM board that supports PCIe 3.0 x4 by installing J6 connector in Jetson AGX Xavier.
Jetson AGX Xavier did not recognize the OEM board.
In “lspci -x”, “0001:00:00.0 PCI bridge: NVIDIA” and “0001:01:00.0 SATA” were shown only.
In other x86 system, the OEM board was rightly recognized in PCIe slot.
I have tried two patches from forms.developer.nvidia.

1)no PCIe link with some devices
→ no effect

  1. PCIe Device - No Link
    → no effect

I monitored the Linux PCIe Driver status for J6 PCIe slot.
The result of moniotring is as like:

  1. In Linux PCIe Driver, J6 PCIe slot is recognized as PCI bus 005.00:00.0
  2. After that, in “pci_scan_bridge→pci_bus_read_dev_vendor_id→……,
    tegra_pcie_dw_link_up() function,
    the value of (pci→dbi_base + CFG_LINK_STATUS_CONTROL) is 0x10110000.
    And “CFG_LINK_STATUS_DLL_ACTIVE” bit(29-th bit) is not active
  3. Because of “not active”, Linux PCIe Driver did not read the vendor id of OEM board.
    So Linux PCIe Driver did not recognized the OEM board installed in J6 PCIe slot.

The kernel soure code is “public_sources.tbz2” released in 2020-07-07.
The result of lspci anlspci.error.txt (564 Bytes) dmesg.error.txt (203.5 KB) d demsg are attached.