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heeralk's avatar
heeralk
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4 years ago

PCIe MCDMA Gen3x16 Simulation : D2H not fetching data as per descriptor size

Hi , I'm using Intel's Pcie MCDMA gen3x16. For D2H descriptor , I'm requesting for 1600 bytes as my payload size. I have enabled Msi interrupt at the end of transfer. I see an issue tha...
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    heeralk
    Icon for New Contributor rankNew Contributor
    4 years ago

    Hi KhaiY ,

    Thanks for your response. So the device is suppose to give back to host 1600 bytes, that's why my d2h payload size is 1600 byte. So I have split into 4 descriptor as below :

    # rx desc addr 00000000000a0000 , size 512 , msix en bit 0 , descriptor count 0
    # rx desc addr 00000000000a0200 , size 512 , msix en bit 0 , descriptor count 1
    # rx desc addr 00000000000a0400 , size 512 , msix en bit 0 , descriptor count 2
    # rx desc addr 00000000000a0600 , size 64 , msix en bit 1 , descriptor count 3

    I have enabled msix only for the last descriptor. still I see the msix interrupt coming after 1154 bytes of data.

    One note :

    My device (ip ) which is giving the data is not giving it continously. it gives 1154 bytes continuously , then it gives the remaining bytes after 1.6us . I have captured my device data waveform in standalone test as below :

    The userguide doesnt mention if the data from device has to be continuous or not.

    Please help me resolve the issue.

    Thanks and Regards

    heeral