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NMR's avatar
NMR
Icon for New Contributor rankNew Contributor
9 months ago

Stratix 10 Phylite IP , deviation in data sampling at different groups(Input Path Signal)

Hi ,

Configuration detail:

Problem Statement:

For group 0 data is sampled correctly as expected but for group 1 data to core signal the data sampled internally by phylite is shifted by 16bits(Starts sampling 2 clk earlier itself)

For checking if it's due to RTL interchanged group 0 and 1 but issue also got reversed, so not an issue from RTL rather internal sampling

So tried increasing rd latency but it only shifts the rd valid signal not the internal sampling.

Query:

Is there a method to control data sampling and address the deviation in data sampling between different groups, even though one group is a copy of the other?

Group 0

Group 1

Memory

7 Replies

  • Farabi's avatar
    Farabi
    Icon for Regular Contributor rankRegular Contributor
    6 months ago

    Hello,


    1. Disable dynamic reconfiguration in the IP and test again
    2. Do not use the group copy feature (setup group 1 manually) and test again


    regards,

    Farabi


  • Farabi's avatar
    Farabi
    Icon for Regular Contributor rankRegular Contributor
    6 months ago

    Hello,


    Bit [8:7] and bit [6:4] are used together to select DQ pins:

    bit[8:4] = {2'h1, 3'h0} -> DQ0

    bit[8:4] = {2'h1, 3'h1} -> DQ1

    bit[8:4] = {2'h1, 3'h2} -> DQ2

    bit[8:4] = {2'h1, 3'h3} -> DQ3

    bit[8:4] = {2'h1, 3'h4} -> DQ4

    bit[8:4] = {2'h1, 3'h5} -> DQ5

    bit[8:4] = {2'h2, 3'h0} -> DQ6

    bit[8:4] = {2'h2, 3'h1} -> DQ7

    bit[8:4] = {2'h2, 3'h2} -> DQ8

    bit[8:4] = {2'h2, 3'h3} -> DQ9

    bit[8:4] = {2'h2, 3'h4} -> DQ10

    bit[8:4] = {2'h2, 3'h5} -> DQ11

    And about the abnormal behavior between groups, could you please run the simulation waveform showing the operation of all PHY Lite IP signals of both groups in one view.


    So we can get the timing relationship of rdata_en, strobe_io, and rdata_valid of both groups in their testbench (and then check if there are any differences)

    Could you please disable the dynamic reconfig in the IP and test again to see if the issue still happen?


    regards,

    Farabi


    • NMR's avatar
      NMR
      Icon for New Contributor rankNew Contributor
      6 months ago

      Hi Farabi,

      Thanks for detailed explanation on dq pin selection.

      Below is the simulation waveform on PHY Lite IP signals for both the group 0 and group 1

      Group 0

      Group 1

  • NMR's avatar
    NMR
    Icon for New Contributor rankNew Contributor
    7 months ago

    Hi Ash_R,

    In dynamic reconfiguration , though I increase the tap value around mid(262) for pin input , I didn't find any delay in actual simulation .I referred the below one. Here I have doubt that how will we select the dq pin between 2 and 9.Additionally at specific pin selection (from 2 to 9) , what I need to keep at field[8:7]?

    Please help me with this

    • NMR's avatar
      NMR
      Icon for New Contributor rankNew Contributor
      8 months ago

      Hi Ash_R,

      Thanks for your consideration.

      I checked this PHY Lite IP configuration settings with the example simulation design where I did not encounter this issue

  • NMR's avatar
    NMR
    Icon for New Contributor rankNew Contributor
    8 months ago
    Hi team,
    I am looking forward for your reply