Re: status of the calgary iommu driver

Jon Mason
2019-05-08T17:57:00Z

On Wed, May 8, 2019 at 6:52 PM Christoph Hellwig <hch@lst.de> wrote:
>
> On Wed, May 08, 2019 at 06:42:39PM +0100, Jon Mason wrote:
> > These systems were plentiful for 2-4 years after the original series
> > made it in. After that, the Intel and AMD IOMMUs should were shipped
> > and were superior to this chip. So, even in systems where these might
> > be present, the AMD/Intel ones should be used (unknown if they were
> > shipped on the same ones, as both Muli and I have left IBM).
> >
> > You thinking about removing the code?
>
> I'm wondering if we could remove it. I've been done lots of
> maintainance on various dma mapping and iommu drivers, and the calgary
> one seems like it didn't get a whole lot of love, and I've not seen
> any recent users, so I mostly wonder if I should bother at all.

I do have a system. So, it could be tested. However given the age of
the HW, I would say it is not worth the effort to update and it would
be best to remove it from the kernel.

I can send a patch to do this, unless you would prefer to do it (or
already have something handy).

Thanks,
Jon