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c6678 EVM on is not found on pcie using TMDXEVMPCI with some motherboards

Other Parts Discussed in Thread: TMDXEVMPCI


I have the following problem with the c6678EVM:

I have connected the card to my PC using TMDXEVMPCI, but the device does not show up with lspci on Linux, neither Windows finds it. In this PC I have a Gigabyte Z8-HD3 motherboard. When I connect the same board with the same settings to an other PC with a different motherboard it is listed by lspci and I can see that the PCIe registers are configured after boot.

I have tried both PCIe slots (a 4x and an 16x one) with the Z8-HD3 motherboard but none of them works: the card boots, I can access it via the USB cable, but it is not recognized by lspci.

Do you know of any compatibility issues with this type of motherboard?

What do you suggest, how do I proceed with this problem?

Thank you,


  • Hi,

    Welcome to the TI E2E forum. I hope you will find many good answers here and in the documents and in the TI Wiki Pages (for processor issues). Be sure to search those for helpful information and to browse for the questions others may have asked on similar topics (

    Please check your PCIe adapter card PCB version. There was some PC compatibility issue with old versions of AMC-to-PCIe adapter card. But the issues are fixed in the new version of adapter card, labeled with “PCB REV: 17-00107-03; PCA REV: 18-00107-03”. Please check the following link for the adapter info

    Please go through below wiki for PCIe related FAQs and Resources.

  • Dear Ganapathi,

    Thank you for the quick answer.

    I have checked my adapter card and it is the new version: "PCB REV: 17-00107-03; PCA REV: 18-00107-03".

    Next, I will check the PCIe debug register. I'll get back to you when I've found something.

    Thanks again,


  • Hi,

    Refer Appendix A on PCIe user guide(SPRUGS6D). Insure link training completion and success by observing LTSSM_STATE field in DEBUG0 register change to 0x11.

  • Dear Ganapathi,

    I've checked the DEBUG0 field and it is not set to 0x11 when the card is not listed by lspci. So far so good, the register should read 0x11 when synchronization is OK, but what to do when sync fails?

    I've read in one of the solutions to wire PCIe_RST to the DSP's RESETz. This seems a little confusing to me. As far as I understand from the TMDXEVM6678L HW documentation the RESETz wire is connected to the FPGA directly in an inner layer. Can you give me any details how this wiring should be made?

    Meanwhile I've tried the board in different PC motherboards. So far I've found only one motherboard, where the card gets listed in lspci after each boot. Other motherboards don't see the board on lspci at all. And there's one specific motherboard which sometimes sees the board in lspci and sometimes not. Can there be other issues besides this PCIe reset?

    Thank you very much,

  • Hi Peter,
    You don't want to connect directly to the RESETz signal of the SOC. There is a switch on the EVM labeled RST_WARM1. This switch signals the FPGA to generate a RESETZ to the C6678. You can connect the PCIe_RST to pin 1 of the RST_WARM1 switch. When PCIe_RST goes low, the FPGA should provide the RESETz signal triggering a warm reset of the C6678.
  • Hello Bill,

    Thank you for your answer. We have connected the RST_WARM1 to PCIe_RST, but unfortunately this does not seem to solve the problem. The reset connection is working, i.e. the DSP is reset when I reset the PC (which was not the case before). However, the device is not enumerated by lspci, except on that one specific PC (see my original post) on which it was working without the reset connected.

    Can you give any further suggestions how to proceed?

    Thanks very much, best regards,

  • Hello,

    Unfortunately, we could not resolve this issue since my last post.

    In an other forum thread

    there was a suggestion to rebuild the IBL. Can this be relevant in our case?

    Thank you,