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pdewanga's avatar
pdewanga
Icon for New Contributor rankNew Contributor
3 years ago
Solved

Determining the Max payload size encoding

Hi Quartus Support Team, Attaching the screen-shot from the "L- and H-tile Avalon® Streaming and Single Root I/O Virtualization (SRIOV) Intel® FPGA IP for PCI Express* User Guide" Table 43. What...
  • Wincent_Altera's avatar
    Wincent_Altera
    3 years ago

    Hi,

    Thanks for correcting me, my apologize for misunderstanding the question.

    For your information the spec is not owned by intel, it is a general spec that all PCIe IP need to follow.

    You can get the detail in "PCI Express® Base Specification" in the web.

    For your question, I do help to printscreen it to you.

    Max rd req size

    Max payload size

    Hope this answer your question, Let me know if this is helpful to you.

    Regards,
    Wincent_Intel

Wincent_Altera's avatar
Wincent_Altera
Icon for Regular Contributor rankRegular Contributor
3 years ago

Hi,

From low level description, it is part of the Transaction Layer (TL) bus provides a subset of the information stored in the Configuration Space. Those Information on the Transaction Layer (TL) bus is time-division multiplexed (TDM). When tl_cfg_func[1:0]= 2'b00, tl_cfg_ctl[31:0] drives PF0 Configuration Space register values for eight consecutive cycles. The next 40 cycles are reserved. Then, the 48-cycle pattern repeats as per mention in the user guide.

Can I know is there any specific reason asking that question ? do you facing problem on the configuration ?

Regards,

Wincent_Intel

pdewanga's avatar
pdewanga
Icon for New Contributor rankNew Contributor
3 years ago

Hi,

The text you copy and pasted is from user guide, that we have gone through.

There is no issue of configuration. I just want to use this two following signal for our design.

[5:3] Max rd req size

[2:0] Max payload size

Actual question to make you more clear-

question:- Please share more details about the encoded value of this signals ( [5:3] Max rd req size [2:0] Max payload size ). What does each state means ?

Please don't copy paste the user guide content, We have gone through that but nothing is listed there properly.

Thanks

  • Wincent_Altera's avatar
    Wincent_Altera
    Icon for Regular Contributor rankRegular Contributor
    3 years ago

    Hi,

    Thanks for correcting me, my apologize for misunderstanding the question.

    For your information the spec is not owned by intel, it is a general spec that all PCIe IP need to follow.

    You can get the detail in "PCI Express® Base Specification" in the web.

    For your question, I do help to printscreen it to you.

    Max rd req size

    Max payload size

    Hope this answer your question, Let me know if this is helpful to you.

    Regards,
    Wincent_Intel

    • pdewanga's avatar
      pdewanga
      Icon for New Contributor rankNew Contributor
      3 years ago

      Hi wchiah,

      Thanks for providing answer.

      Regards,

      Piyush

      • Wincent_Altera's avatar
        Wincent_Altera
        Icon for Regular Contributor rankRegular Contributor
        3 years ago

        Hi Piyush,

        Thanks for your reply, With that said I will close this case on my place.

        The community users will be able to help you with your follow-up questions.

        If you have new problem, feel free to open another community thread.

        If you feel your support experience was less than a 9 or 10,

        please allow me to correct it before closing or please let me know the cause so that I may improve your future support experience.

        Regards,

        Wincent_Intel