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SKuma36's avatar
SKuma36
Icon for Occasional Contributor rankOccasional Contributor
7 years ago

Arria10 PCIe Hard IP link bring up issue

Hi,

We are trying to bring-up PCIe (Gen1 x1) interface using Arria 10 PCIe Hard IP on Intel's Arria10 Signal Integrity development board.

The design is found to be working in simulation, but on the board, the link doesn't come up. The PCIe LTSSM state is stuck at 0, looks like receiver detection is not happening. The core_clock o/p from the PCIe core looks fine.

We are suspecting PCIe serial link connectivity issue. As per the board document, we could see 10 transceiver channels being connected to the Hard IP. Any idea, which transceiver to be used for Gen1 x1 purpose? Any other pointers to debug this would be of great help.

rgds,

sunil

17 Replies

  • SengKok_L_Intel's avatar
    SengKok_L_Intel
    Icon for Regular Contributor rankRegular Contributor

    ​Hi Sunil,

    Yes, this is possible if you have your own soft PCIe IP or from third party.

    Regards -SK

  • SKuma36's avatar
    SKuma36
    Icon for Occasional Contributor rankOccasional Contributor
    Hi SK, Even if we have our own soft PCIe IP core, we should still use Arria10 Native Transceiver PHY, right? In that case, can we configure the transceiver for PCIe protocol? Rgds, sunil
  • SKuma36's avatar
    SKuma36
    Icon for Occasional Contributor rankOccasional Contributor
    Hi SK, As suggested by you in an earlier email, I thought of using the TTK for Transceiver link debugging. Do we have any example designs that we can use for this? If so, could you pl. share the link for the same? Pl. note that we are using Arria 10 Signal Integrity development board. Rgds, sunil
  • SKuma36's avatar
    SKuma36
    Icon for Occasional Contributor rankOccasional Contributor
    Hi SK, Thanks for the info. BTW, I tried using the Arria10 SI Board Test system application for testing the transceivers. None of the transceivers connected to Bulls eye connector works in external loopback mode (see attached snapshot). I tried varying the PMA settings, but didn’t see any data looped back from TX to RX side. Any idea what could be causing this issue? The internal serial loopback mode test works fine though. FYI, the transceivers connected to the 2.4 SMA connectors on the board worked fine in external loopback mode when tested with the Board test system application. Rgds, sunil
  • SengKok_L_Intel's avatar
    SengKok_L_Intel
    Icon for Regular Contributor rankRegular Contributor

    ​Hi Sir,

    To confirm your design is working fine for the external loopback, you can change the pin assignment to the channel that using 2.4 SMA connectors. If this passed, then you need to double check on your hardware setup. And maybe using a scope to confirm if there is a signal sending out from TX.

    Regards -SK

  • SKuma36's avatar
    SKuma36
    Icon for Occasional Contributor rankOccasional Contributor
    Hi SK, Our design works fine for the external loopback with the channel connected to 2.4 SMA connector. For the channel connected to High Density bulls eye connector, it’s not working. As suggested, we will try to use a scope and see if we could see data on TX lines. Rgds, sunil