Re: [PATCH] iommu: Remove stub functions for !CONFIG_IOMMU_API

Roedel, Joerg
2011-08-29T12:25:30Z

On Mon, Aug 29, 2011 at 06:59:05AM -0400, Ohad Ben-Cohen wrote:
> On Mon, Aug 29, 2011 at 1:15 PM, Roedel, Joerg <Joerg.Roedel@amd.com> wrote:
> > Isn't the abstraction that the drivers use the dma-api? There should be
> > an implementation that doesn't require the iommu-api for such devices,
> > no?
>
> Before we boot a remote processor device we often need to map it to
> some (specific) bus addresses (e.g. to allow the processor access to
> certain peripheral devices), and we're doing it directly with the
> IOMMU API.
>
> Do you think this kind of functionality should be added to the DMA API as well ?
>
> IIRC, it was suggested awhile ago but you supported using the IOMMU
> API directly in this case.

Right, when the system has an iommu then the iommu-api is the right
choice to do that. But how to you handle this on systems without an
iommu?

Joerg

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