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Mikhail_a's avatar
Mikhail_a
Icon for Occasional Contributor rankOccasional Contributor
22 days ago

Agilex-7 AXI MCDMA for PCIe hang

Hi!  I'm working with AGIB023R18A1E1VC device and having issues with AXI Multichanned DMA IP for PCIe. Since I require a PCIe bridge, I configured the IP in MCDMA+BAS+BAM mode (PCIe Gen 4, 512-bit)...
Pcie
Mikhail_a's avatar
Mikhail_a
Icon for Occasional Contributor rankOccasional Contributor
21 days ago

Hi VenT_Altera​ 

  1. Could you attach the AXI MCDMA .ip file so we can review the parameter settings?

I will attach an archive with the whole subsystem we use

  1. Which design example variant and which driver did you use?

Unfortunately I don't remember what particular example design we used. We use our own driver for our device, but it does nothing with PCIe itself.

  1. Is the issue first observed in Q25.1, then in Q25.3.1? Did it work correctly prior to Q25.1?

There was no AXI MCDMA for PCIe before 25.1 version. At least it was the first version where we started to use this IP core.

  1. Are you using an Altera Dev Kit or a custom board?

We use Bittware IA-440i board

  1. Could you share the STP when the issue occurs?

Not at the moment, but we see no protocol errors there.

  1. Could you provide the exact steps to reproduce the issue?

One may just create an example design for BAS+BAM mode and then try to write 449 bytes to BAS. With the subsustem in attachments it should not take much time.

VenT_Altera's avatar
VenT_Altera
Icon for Frequent Contributor rankFrequent Contributor
16 days ago

Hi Mikhail_a 

Thank you for your reply.


Since you are using your own driver and application, to isolate whether the issue is software or hardware, please run our Example Design on your board. Port the Example Design to your platform and run the accompanying application. Follow the steps in the user guide to generate Example Design and run the application. https://docs.altera.com/r/docs/817911/25.3.1/axi-multichannel-dma-ip-for-pci-express-user-guide/functional-description?tocId=ak5zOaugZ0426etSxKRO0Q
You may generate the AXI-MM DMA Example Design and use the Custom or DPDK driver to perform the perfq_app or mcdma_test: AXI-MM DMA test. Please share your test results.

Also, could you share the design goal for your implementation? If MCDMA is not required, you might consider using BAM + BAS (user mode) to simplify the design.

Thanks.
Best Regards,
Ven 

  • VenT_Altera's avatar
    VenT_Altera
    Icon for Frequent Contributor rankFrequent Contributor
    15 days ago

    Hi Mikhail_a 

    I understand that you observed the failure in Example Design as well. Let's focus on the Example Design. Please provide the log from the prerequisites setup to running the application and hit the errors. I'd like to see the exact commands and their output. Which driver (Custom or DPDK) and which AXI-MM DMA test did you perform (perfq_app or mcdma_test)? Please share the detailed steps in the log.  

    Thanks.
    Best Regards,
    Ven