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Date: Fri, 26 Jan 2024 11:17:01 -0400
From: Jason Gunthorpe <jgg@ziepe.ca>
To: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Cc: iommu@lists.linux.dev, linuxppc-dev@lists.ozlabs.org,
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Subject: Re: [PATCH 1/2] powerpc: iommu: Bring back table group
 release_ownership() call
Message-ID: <20240126151701.GZ50608@ziepe.ca>
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On Fri, Jan 26, 2024 at 08:43:12PM +0530, Shivaprasad G Bhat wrote:
> > Also, is there any chance someone can work on actually fixing this to
> > be a proper iommu driver? I think that will become important for power
> > to use the common dma_iommu code in the next year...
> We are looking into it.

Okay, let me know, I can possibly help make parts of this happen

power is the last still-current architecture to be outside the modern
IOMMU and DMA API design and I'm going to start proposing things that
will not be efficient on power because of this.

I think a basic iommu driver using the dma API would not be so hard.

I don't know what to do about the SPAPR VFIO mess though. :(

Jason