Re: [PATCH v11 3/7] iommu: Add verisilicon IOMMU driver

[Benjamin Gaignard]

Le 18/01/2026 à 10:41, Jörg Rödel a écrit :
> Benjamin,
>
> On Tue, Jan 13, 2026 at 04:10:51PM +0000, Will Deacon wrote:
> > I took another look at this to see whether it had changed significantly
> > from v6 when compared to the rockchip driver. Sadly, they still look
> > very similar to me and I continue to suspect that the hardware is a
> > derivative. I really don't understand why having a shared implementation
> > of the default domain ops is difficult or controversial. Have you tried
> > to write it?
> When updating for v12, can you please put an explanatory comment at the top of
> the file explaining the relationship of the IP this driver is for to the
> RockChip IOMMU and the rationale for having it as a separate driver? I want
> this part of the discussion documented in the code in case it comes up again.

Does the follow wording summarize the situation correctly for you if I put it
in header comment ?

 * This hardware block is using a 2 pages tables allocation structure.
 * That make very similar to Rockhip iommu hardware blocks but it has
 * it own driver because the registers offset and configuration bits
 * are completely different. An additional raison is that this hardware
 * has been developped by Verisilicon to be used by their hardware video
 * decoders and for a general purpose like Rockchip iommus.

Regards,
Benjamin

> -Joerg