Re: [PATCH v2 02/23] xen/arm: smmuv3: Add support for stage-1 and nested stage translation

[Julien Grall <julien@xxxxxxx>]

Hi Milan,

On 23/03/2026 22:51, Milan Djokic wrote:
> From: Rahul Singh <rahul.singh@xxxxxxx>
>
> Xen SMMUv3 driver only supports stage-2 translation. Add support for
> Stage-1 translation that is required to support nested stage
> translation.
>
> In true nested mode, both s1_cfg and s2_cfg will coexist.
> Let's remove the union. When nested stage translation is setup, both
> s1_cfg and s2_cfg are valid.
I am not entirely sure where to comment. Looking at Linux [1], it seems 
some SMMU variant have errata for the nesting mode. Should we at least 
prevent nested on both variant for now?
Cheers,

[1] 
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=0bfbfc526c70606bf0fad302e4821087cbecfaf4
--
Julien Grall