Re: [PATCH 4/5] media: apple: Add Apple ISP driver

[Janne Grunau]

On Sun, Feb 23, 2025 at 09:48:30AM +0100, Sasha Finkelstein wrote:
> On Wed, 19 Feb 2025 at 12:34, Janne Grunau <j@xxxxxxxxxx> wrote:
> > > +     while (maps < end) {
> > > +             maps++;
> > > +             maps = of_translate_dma_region(dev->of_node, maps, &heap_base,
> > > +                                            &heap_size);
> > > +     }
> >
> > The hand-rolled reserved memory parsing looks like it can be replaced
> > with of_iommu_get_resv_region();
> 
> I have looked into it, and `of_iommu_get_resv_region` does the wrong
> thing. We fill out `reg`, and it grabs that instead of `iommu-addresses`.

Downstream commit 704ace01cd3c4 [0] ("iommu: Add IOMMU_RESV_TRANSLATED
for non 1:1 mapped reserved regions") adds device virtual addresses to
struct iommu_resv_region. Sorry for the added dependency but it is
required anyway for the isp to work.

ciao Janne

[0] https://github.com/AsahiLinux/linux/commit/704ace01cd3c423b1e2492f0777d9c4c0f3404d8