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JET60200's avatar
JET60200
Icon for Contributor rankContributor
6 years ago

A10 AVMM DMA has only a single MSI to Host, how to distinguish this DMA completion is from READ DMA controller, or from WRITE DMA controller?

hi everyone, ​ I'm using Arria10 which is PCIe EP in X86 Host. Per my understanding, Altera AVMM-DMA only provides single MSI to notify the DMA is completion(both READ DMA controller and WRITE DMA ...
SengKok_L_Intel's avatar
SengKok_L_Intel
Icon for Regular Contributor rankRegular Contributor
6 years ago

Hi,

When the driver receives the interrupt, it can poll the DONE bit of each descriptor to make sure all descriptors are finished, it is either write or read DMA , you can poll both to confirm.

Regards -SK

  • JET60200's avatar
    JET60200
    Icon for Contributor rankContributor
    6 years ago

    Thanks SK,

    ​

    If there's no independent IRQ NO for AVMM-DMA Read or Write, try to query DONE BIT seems the only method to know whether irq comes from READ DMA or WRITE DMA, even though this way is n't so straightforward.

    ​

    Thanks for suggestion.

    Best regards ​