[PATCH v3 9/9] docs: document WID DT properties

[Yu-Chien Peter Lin]

Hi Radim,

On Fri, Oct 30, 2026 at 12:49:08PM +0000, Radim Krcmar wrote:
> 2026-10-27T16:35:09+08:00, Yu-Chien Peter Lin <peter.lin at sifive.com>:
> > Add "wid" and "widdeleg" properties to domain instance node
> > documentation and example DT. Add a "Root Domain Node" section
> > describing the "root" subnode under the domain configuration
> > node for root domain WID configuration
> >
> > Signed-off-by: Yu-Chien Peter Lin <peter.lin at sifive.com>
> > ---
> > Change v2->v3:
> > - Mark 'wid' property as mandatory when Smlwid is present for both root
> >   and domain instance nodes.
> > - Remove mention of M-mode WID fallback when 'wid' is absent.
> > ---
> > diff --git a/docs/domain_support.md b/docs/domain_support.md
> > @@ -205,6 +225,13 @@ The DT properties of a domain instance DT node are as follows:
> > +* **wid** (Mandatory if Smlwid is present) - The 32-bit World ID for
> > +  lower-privilege modes (S/U-mode) for the domain instance. If the hart
> > +  supports the Smlwid extension, this property must be provided.
> 
> WID CSR field with Smlwid is log_2(MXLEN)-bit.
> 
> > +* **widdeleg** (Optional) - The 64 bit World ID delegation bitmask for
> 
> mwiddeleg CSR with Smwiddeleg is MXLEN-bit.
> 
> BIT_ULL(dom->wid) in [6/9] is UB because DT parser allows WID above
> MXLEN, but it's easy to blame the platform for that...
> How much do we want to sanitize the DT?

Indeed, I will refine the document and agreed we should be careful on
processing inputs used by the security feature. Let me take some time
to review the series.

Thanks,
Peter Lin

> 
> Thanks.