CPU Cache and busdma usage in USB

Hans Petter Selasky hselasky at c2i.net
Mon Jun 29 12:25:17 UTC 2009

On Monday 29 June 2009 14:16:13 Piotr Zięcik wrote:
> Look for bus_dmamap_sync() sync description, last sentence:
> <cite>
> If read and write operations are not preceded and followed by the
> appropriate synchronization operations, behavior is undefined.
> </cite>

I don't think this is a problem. I do flush read buffers before using them, 
and invalidate them afterwards. Write buffers only get flushed once.


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