Arria V Hard Processor System Technical Reference Manual
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Ixiasoft
Visible to Intel only — GUID: suc1442503236215
Ixiasoft
19.4.1.9. DMA
If the controller is functioning as a generic root hub, you should program your software to select the buffer DMA mode that supports split transfers.
If generic root hub functionality is not required, or if the controller is configured in Device mode, you can program your software to select scatter-gather DMA mode.
- A soft reset must be issued before changing modes.
- If buffer DMA mode is selected, then the Host mode periodic request queue depth must not be set to 16.
- Devices must be re-enumerated.