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To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: Interrupt routing broken on TiBook IV with 2.6.21.x ?
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Benjamin Herrenschmidt wrote:

> I'm not sure what you are talking about here. DMA mapping has existed in
> linux for years.

I do admit that it's been a while since that last look ;)  The topic came up
when discussing PCI and bus systems in general with micro/real-time kernel
people whom I assumed to be experts in this since they had Linux kernels
running on top of their scheduling scheme.  As it turned out, using an
abstraction such as a DMA map was a totally new concept to them.  They
even questioned the usefulness of such an approach.


Cheers,
Christian