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Altera_Forum's avatar
Altera_Forum
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16 years ago

PCIe and Nios in SOPC builder

Hallo all,

I'm trying to build a system with two DMAs PCIe compiler and Nios as a DMAs controller. I'm reading DMA descriptor from host (using the Tx PCIe interface) config the DMA Rx and DMA TX the configuration seems to be o.k. (the length of the transaction writing well to the length register). The problem that the DMA operate just partial transaction and stuck. I really will be happy to get a help! As any one pace this problem or have any advice?

7 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    make sure bursting is off and you don;t have unaligned transfers on.

    --dalon
  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    The transfer with burst on has to work too. I'm using DMA Controller and PCIEx Core, and i had problem with length transfer multiple of less 8 bytes.

  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    I successes now to transfer burst.

    But because my host is 64bit and the avalon is 32bit, I needed to connect read and write to tx_interface at the PCIe core(I added unnecessary arbitration on both interface!)

    That the only way it's work - did you handle anything similar? Thanks.
  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    Yes, you needs to connect read and write interfaces of dma controller to tx_interface.

  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    and why is it so?

    is it write any where? or did you figure it out alone?