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Altera_Forum's avatar
Altera_Forum
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12 years ago

Handle DMA Page address received at the FPGA end during DMA transfer

Scatter Gather DMA transfer of 461KB is initiated from the Host PC to the ARRIA2GX FPGA using Jungo Driver. During the transfer apart from the actual data sent as input data , extra data which ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
12 years ago

I have no experience with PCI Express so I can't answer you directly, but this triggered my attention:

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Scatter Gather DMA transfer of 461KB

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are you transferring those with only one descriptor, or with a chain of descriptors? AFAIK the SGDMA core is limited to 64kb transfers, so if you try to transfer more than this amount with a single descriptor, you will probably run into strange results.

Can you put a signaltap probe on the stream interface on the SGDMA to check that the data packets are transferred correctly?