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lambert_yu's avatar
lambert_yu
Icon for Contributor rankContributor
5 years ago

About timing request analysis of quartus 16.0

Hi sir/madam,

When I synthesize one project with DDR4 module, I face one strange probelm:

I constrained DDR4 refclk in my sdc file and set -exclusive for this DDR4 refclk, but from the sta report, It presents the timing violation which occured at the DDR4 refclk domain, but from the timing violation path, I found that these paths belongs to the DDR4_emif_o_refclk(DDR4 controller outputs) domain and there is no rationship with DDR4 refclk. So I don't know what's wrong? Of course, now I don't assignments pins for all I/O pins in top-level, but I don't think this effects the timing analysis. So, Could someone will help me or give me some advice about this problem?

Brs,

Lambert

2 Replies

  • sstrell's avatar
    sstrell
    Icon for Super Contributor rankSuper Contributor
    5 years ago

    What device are you using? Is this a hardened EMIF or soft? Yes, the placement of pins would have an effect on timing analysis. Make sure all of your constraints, including I/O pin locations, are created to get an accurate analysis.

    • lambert_yu's avatar
      lambert_yu
      Icon for Contributor rankContributor
      5 years ago

      Hi sstrell,

      Device : arria 10 , 10ax115s2f45i1sg

      EMIF: hard controller & PHY

      Pin placement: no placement constrains for all EMIF interfaces (make quartus II assignment automatically)

      And I found that I make one ddr refclk constrains in my .sdc file though there is one ddr refclk constrains in the .sdc file which generated with EMIF IP generation, and there is timing violation; And if I don't make this clock constrains in my .sdc file, there is no timing violation apperence. I think this constrain conflicts with the content of the clock constraints in EMIF.

      Brs,

      Lambert