Re: [PATCH v8 09/10] dt-bindings: interconnect: Add interconnect-tags bindings

[Sibi Sankar]

On 2020-05-20 01:27, Saravana Kannan wrote:
> On Tue, May 19, 2020 at 11:58 AM Rob Herring <robh@xxxxxxxxxx> wrote:
> > On Tue, May 12, 2020 at 03:53:26PM +0300, Georgi Djakov wrote:
> > > From: Sibi Sankar <sibis@xxxxxxxxxxxxxx>
> > >
> > > Add interconnect-tags bindings to enable passing of optional
> > > tag information to the interconnect framework.
> > >
> > > Signed-off-by: Sibi Sankar <sibis@xxxxxxxxxxxxxx>
> > > Signed-off-by: Georgi Djakov <georgi.djakov@xxxxxxxxxx>
> > > ---
> > > v8:
> > > * New patch, picked from here:
> > >   https://lore.kernel.org/r/20200504202243.5476-10-sibis@xxxxxxxxxxxxxx
> > >
> > >  .../devicetree/bindings/interconnect/interconnect.txt        | 5 +++++
> > >  1 file changed, 5 insertions(+)
> > >
> > > diff --git a/Documentation/devicetree/bindings/interconnect/interconnect.txt b/Documentation/devicetree/bindings/interconnect/interconnect.txt
> > > index 6f5d23a605b7..c1a226a934e5 100644
> > > --- a/Documentation/devicetree/bindings/interconnect/interconnect.txt
> > > +++ b/Documentation/devicetree/bindings/interconnect/interconnect.txt
> > > @@ -55,6 +55,11 @@ interconnect-names : List of interconnect path name strings sorted in the same
> > >                        * dma-mem: Path from the device to the main memory of
> > >                                   the system
> > >
> > > +interconnect-tags : List of interconnect path tags sorted in the same order as the
> > > +                 interconnects property. Consumers can append a specific tag to
> > > +                 the path and pass this information to the interconnect framework
> > > +                 to do aggregation based on the attached tag.
> >
> > Why isn't this information in the 'interconnect' arg cells?
> >
> > We have 'interconnect-names' because strings don't mix with cells. An
> > expanding list of 'interconnect-.*' is not a good pattern IMO.

Rob,
Currently the interconnect paths
assume a default tag and only few
icc paths require tags that differ
from the default ones. Encoding the
tags in the interconnect arg cells
would force all paths to specify
the tags. I guess that's okay.


> Also, is there an example for interconnect-tags that I missed? Is it a
> list of strings, numbers, etc?

Saravana,
https://patchwork.kernel.org/patch/11527589/
^^ is an example of interconnect-tag useage.

> -Saravana

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