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KoenVe's avatar
KoenVe
Icon for New Contributor rankNew Contributor
1 month ago

TSE -> SGDMA -> SOC(through f2sdram)

Hi,

I'm trying to transfer an old design with multiple TSEs / SGMDAs and a NIOS to a newer Agilex 5.
We are also evaluating the use of the SOC instead of the NIOS in the design.
I've made a minimized platform design for it but it fails during synthesis with the notorious error for the f2sdram bus:

There is both a 'memory -> streaming' and 'streaming -> memory' sgdma in the design present, so both read and write port on the axi bus should be present.
If I connect the SGDMA's to the fpga2hps bus the same error is generated.

Are there settings in the SGDMAs that needs to be set to a certain value so that the correct read/write avalon MM/AXI interface is generated?

4 Replies

  • YoshiakiS_Altera's avatar
    YoshiakiS_Altera
    Icon for Occasional Contributor rankOccasional Contributor

    Hello KoenVe,

    The error has been reproduced, and we are currently investigating it.

    Best regards,

     Yoshiaki

    • YoshiakiS_Altera's avatar
      YoshiakiS_Altera
      Icon for Occasional Contributor rankOccasional Contributor

      Hello KoenVe,

      The root cause was identified.

      The active-low reset signal for the F2SDRAM bridge was left unconnected in the top-level design. As a result, Quartus tied the reset signal low and determined that the F2SDRAM bridge was not required. Consequently, the F2SDRAM_RDATA signal became unconnected, leading to the unconnected signal error.

      Actual signal is below.

          -- reset signal (no need to synchronize as it is expected that the reset bridge in the Qsys module does the synchronization)
          sReset_n <= sEmif_cal_done_rst_n; -- pFPGA_RESETn & sEmif_local_reset_done;

      After tying sReset_n to logic high ('1'), the error no longer occurred.

      Lastly, while reviewing the design, I have a few comments.

      As described in the user guide below, Platform Designer automatically performs protocol conversion between AXI and Avalon buses, allowing AXI and Avalon interfaces to be connected directly. This conversion includes both bus width adaptation and burst transfer conversion.

      Quartus® Prime Pro Edition User Guide

      1. Platform Designer Interconnect

      https://docs.altera.com/r/docs/683609/26.1/quartus-prime-pro-edition-user-guide/platform-designer-interconnect

      Platform Designer allows you to establish connections between Avalon® and AXI interfaces by generating an interconnect logic. This logic enables you to handle the protocol differences. Platform Designer creates the interconnect logic by converting all the protocols to a proprietary packet format. Then, the tool routes the packet through network switches to the appropriate AXI subordinates or Avalon agents. Here, the packet converts to the subordinate's protocol.7

      Platform Designer supports Avalon® , AMBA® 3 AXI (version 1.0), AMBA® 4 AXI (version 2.0), AMBA® 4 AXI-Lite (version 2.0), AMBA® 4 AXI-Stream (version 1.0), AMBA ACE5-Lite, and AMBA® 3 APB (version 1.0) interface specifications.

      Best regards,

        Yoshiaki

      • YoshiakiS_Altera's avatar
        YoshiakiS_Altera
        Icon for Occasional Contributor rankOccasional Contributor

        Hello KoenVe,

        Do you have any further questions?

        Best regards,

         Yoshiaki