[RFC 0/6] iommu: generic api migration and grouping

Ohad Ben-Cohen ohad at wizery.com
Mon Jun 6 11:15:30 EDT 2011

Hi Joerg,

On Mon, Jun 6, 2011 at 1:09 PM, Roedel, Joerg <Joerg.Roedel at amd.com> wrote:
> The IOMMU-API already supports multiple page-sizes. See the
> 'order'-parameter of the map/unmap functions.

This is insufficient; users need somehow to tell what page sizes are
supported by the underlying hardware (we can't assume host page-sizes,
and we want to use bigger pages whenever possible, to relax the TLB

>>   Further generalizing of iovmm strongly depends on our broader plans for
>>   providing a generic virtual memory manager and allocation framework
>>   (which, as discussed, should be separated from a specific mapper).
> The generic vmm for DMA is called DMA-API :) Any reason for not using
> that (those reasons should be fixed)?

This is definitely something we will look into (dspbridge will need it
too, not only omap3isp).


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