On Wednesday 15 June 2011, Michal Nazarewicz wrote:

On Tue, 14 Jun 2011 22:42:24 +0200, Arnd Bergmann [off-list ref] wrote:

quoted

* We still need to solve the same problem in case of IOMMU mappings
  at some point, even if today's hardware doesn't have this combination.
  It would be good to use the same solution for both.

I don't think I follow.  What does IOMMU has to do with CMA?

The point is that on the higher level device drivers, we want to
hide the presence of CMA and/or IOMMU behind the dma mapping API,
but the device drivers do need to know about the bank properties.

If we want to solve the problem of allocating per-bank memory inside
of CMA, we also need to solve it inside of the IOMMU code, using
the same device driver interface.

	Arnd