RE: gic700 shareability question

[Peng Fan]

> Subject: Re: gic700 shareability question
> 
> On Mon, Apr 03, 2023 at 01:36:31AM +0000, Peng Fan wrote:
> > Hi Marc,
> >
> > > Subject: Re: gic700 shareability question
> > >
> > > + Lorenzo
> > >
> > > On Tue, 28 Mar 2023 13:48:19 +0100,
> > > Peng Fan <peng.fan@xxxxxxx> wrote:
> > > >
> > > > Hi Marc,
> > > >
> > > > We have an SoC that use GIC-700, but not support shareability,
> > >
> > > Define this. The IP does support shareability, but your integration
> doesn't?
> > >
> > > > Currently I just hack the code as below. Do you think it is
> > > > feasible to add firmware bindings such that these can be used to
> > > > define the correct shareability/cacheability instead of relying on
> > > > the programmability of the CBASER register?
> > > >
> > > > Saying with "broken-shareability", we just clear all the
> > > > shareability settings.
> > >
> > > This is the same thing as the Rockchip crap, so you are in good company.
> > >
> > > I've repeatedly stated that this needs to be handled:
> > >
> > > - either by describing the full system topology and describe what is
> > >   in the same inner-shareable domain as the CPUs, which needs to
> > >   encompass both DT and ACPI (starting with DT seems reasonable),
> > >
> >
> > We will give a look on this. But honestly not have a good idea on how.
> 
> It is a longer term fix for the issue, we are looking into this.
> 
> > > - or as a SoC specific erratum, but not as a general "sh*t happened"
> > >   property.
> >
> > I will ask the hardware team to create an errata.
> > >
> > > AFAIK, Lorenzo is looking into this.
> >
> > Lorenzo, are you working on this?
> 
> Yes it is being worked on, that does not prevent though an errata
> workaround to be applied, firmware bindings definitions can take a while to
> sort out.

Sure, we need go with errata. Thanks for working on this.

Thanks,
Peng.
> 
> Lorenzo