Any restrictions on DMA address boundry?

[Eugene Surovegin]

At 11:26 AM 9/25/2003, Roland Dreier wrote:
>People often come up with complicated schemes like flushing and
>invalidating the cache before and after the DMA transfer, but there's
>always a scenario where the DMA buffer and/or the unrelated data get
>corrupted.  The only solution is to make sure that you don't put
>unrelated data in the same cache line as a DMA buffer.

Well, I'm one of those strange people.
Actually, those schemes are quite trivial and they help in _real_ life.

I fully understand that they are not 100% foolproof, but I think they are
_better_ than doing _nothing_.
I already _wasted_ a lot of my time debugging cache coherency problems.

I cannot audit _all_ drivers/subsystems I use nor I can force their authors
do this.

Eugene.


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