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AMa's avatar
AMa
Icon for New Contributor rankNew Contributor
5 years ago

DDR4 校准不过

Hi

我们客户用了8片DDR4，分为两组，每组64bit。

布线前，分配IO检查过，fitter能跑过。

现在问题是，上电后，local_cal_fail拉高，校准不过。

我检查过时钟，给的100M 参考，与IP内对应，电源1.2V与0.6V的参考都是ok的。

上电后，IP的emif_usr_clk能正常出来，说明参考时钟正常进去了，然后时钟出来了？

我也试过降频测试，从1200M降到800M，但是都依然出现校准不过。

用toolkit测，8个group校准都fail了

3 Replies

  • NurAida_A_Intel's avatar
    NurAida_A_Intel
    Icon for Frequent Contributor rankFrequent Contributor
    5 years ago

    Hi,

    Good day to you. 😊

    May I know which stage it is failing on the EMIF Toolkit? Is it a consistent group's failure or intermittent ?

    At the meantime, you can go through the “Check list for troubleshooting calibration failure” that available in link below and see which item might be applicable in your case.

    Calibration Checklist: https://www.intel.com/content/www/us/en/programmable/support/support-resources/support-centers/devices/cfg-index/calibration-checklist.html

    I also suggest you to generate DDR4 example design, with same device and all the memory setting and see if the calibration pass/fail. This will help to isolate further as below:

    • If it passed, then you know that issue is possibly related to board issue or any other build issue.
    • If it failed, then highly it’s DDR4 interface issue.

    Let me know your feedback.

    Thanks

    Regards,

    Aida

  • AMa's avatar
    AMa
    Icon for New Contributor rankNew Contributor
    5 years ago

    Hi, Aida

    ​

    Thanks for your relpy, I had solved this issue. The reason is Alert_n connect to 1.2V.

    • NurAida_A_Intel's avatar
      NurAida_A_Intel
      Icon for Frequent Contributor rankFrequent Contributor
      5 years ago

      Hi,

      Glad to know everything is working fine at your side now. 😊

      Feel free to post any question if you need help/support in future.

      Thank you and have a nice day!

      Regards,

      Aida