Re: [RFC v2 0/5] dmaengine: Slave DMA interface and example users

[David Brownell]

On Tuesday 29 January 2008, Haavard Skinnemoen wrote:
>
> Btw, there's one issue I forgot to mention: I believe the DMA Engine
> framework is currently misusing the DMA mapping API, and this patchset
> makes things worse.
> 
> Currently, the async_tx bits of the API do the required calls to
> dma_map_single() and/or dma_map_page(), but they rely on the driver to
> do the unmapping. This is problematic ...
> 
> How do we solve this?

How about:  for peripheral DMA, don't let the engine see anything
except dma_addr_t values.

The engine needs to be able to dma_alloc_coherent() memory too,
which is pre-mapped.

- Dave
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/