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dj-park's avatar
dj-park
Icon for Occasional Contributor rankOccasional Contributor
2 years ago

Assembler's bitstream generation time in partial reconfiguration flow

Hi, I initially had a question in different forum(Intel Quartus Prime Software, here), but was recommended to ask question here.

I am using Quartus Prime Pro 22.2 ver. I have many PR regions(>100), and it takes 9 min to generate a full bitstream(.sof). I turned off the setting to generate partial bitstream(.rbf files). In the flat design without partial reconfiguration, it takes only 1 min to generate full bitstream.

Is this 9 min of a long bitstream generation time expected?

I think the current Quartus software doesn't seem to support generating a partial bitstream only without generating a full bitstream (which is possible in Xilinx Vivado). I wonder if there is any way to shorten the full bitstream generation time.

5 Replies

  • RichardT_altera's avatar
    RichardT_altera
    Icon for Super Contributor rankSuper Contributor
    2 years ago

    Wow. First time seeing so many PR region!!

    I not too sure why the time to generate the sof file is difference between normal design flow vs PR design flow.

    Haven't see this kind of scenario before.

    My best guess is most likely the additional generated files .msf and the .pmsf file during the programming file generation.

    And perhaps the number of PR regions may affect the time to generate the file?

    Check if you notice any difference in the assembly report.

    If you could share the design, maybe I could dig around and investigate on this?

    Best Regards,

    Richard Tan

  • dj-park's avatar
    dj-park
    Icon for Occasional Contributor rankOccasional Contributor
    2 years ago

    Thanks for the reply @RichardTanSY_Altera .
    In fact, I wasn't too surprised. I've noticed that even if I had small number of PR regions(let's say 5), I did observe slightly longer full bitstream generation time. So if the number increases, I would expect that there's a chance that the full bitstream generation time increases too.

    I disabled the generation of .rbf files, but based on the date that files are generated, it takes a long time to generate a .sof file. Also, note that 9 min is just the time to generate .sof file. (I am not sure what exactly happens underneath the "quartus_asm" command, but it seems like .sof file is generated and then .pmsf file is used to generate .rbf file. Somehow it takes long time to generate .sof file at the first place.)

    I don't think there's direct message functionality.. I will send you the link for the project if you let me know your email address.

  • RichardT_altera's avatar
    RichardT_altera
    Icon for Super Contributor rankSuper Contributor
    2 years ago

    I believe this is expected behavior.

    I tried with different design, (1 min flat design vs 5 min partition design), all having a longer compilation time with partition design.

    This was explained by sstrell in the previous post - compilations with partitions and LL regions will always take longer because of the additional checking, preservation, and restrictions required by the compiler for partition design vs. a flat design where the tool can put design resources anywhere it wants.


    Best Regards,

    Richard Tan


    • dj-park's avatar
      dj-park
      Icon for Occasional Contributor rankOccasional Contributor
      2 years ago

      Thanks for the check.
      This is sad ;-( Hope to see some enhancements Quartus's future release.

  • RichardT_altera's avatar
    RichardT_altera
    Icon for Super Contributor rankSuper Contributor
    2 years ago

    It is what it is. Unless we have a good justification (like reduce hours of compilation time) or a lot of customers want this enhancement (high market value), else it will never see the light. : /

    As your question has been addressed, I now transition this thread to community support.

    Thank you.

    Best Regards,

    Richard Tan