[PATCH v2 1/1] arm64: Add DTS support for FSL's LS1012A SoC

Shawn Guo shawnguo at kernel.org
Sun Sep 4 18:46:36 PDT 2016


On Tue, Aug 30, 2016 at 02:07:17PM +0000, Stuart Yoder wrote:
> > On Mon, Aug 29, 2016 at 12:51:01PM -0500, Scott Wood wrote:
> > > On Mon, 2016-08-29 at 17:52 +0800, Shawn Guo wrote:
> > > > On Fri, Aug 26, 2016 at 03:57:21PM +0530, Bhaskar Upadhaya wrote:
> > > > >
> > > > > +		clockgen: clocking at 1ee1000 {
> > > > > +			compatible = "fsl,ls1012a-clockgen";
> > > > The compatible cannot be found in binding docs.
> > >
> > > From Documentation/devicetree/bindings/clock/qoriq-clock.txt:
> > >
> > > - compatible: Should contain a chip-specific clock block compatible
> > >         string and (if applicable) may contain a chassis-version clock
> > >         compatible string.
> > >
> > >         Chip-specific strings are of the form "fsl,<chip>-clockgen", such as:
> > >         * "fsl,p2041-clockgen"
> > >         * "fsl,p3041-clockgen"
> > >         * "fsl,p4080-clockgen"
> > >         * "fsl,p5020-clockgen"
> > >         * "fsl,p5040-clockgen"
> > >         * "fsl,t4240-clockgen"
> > >         * "fsl,b4420-clockgen"
> > >         * "fsl,b4860-clockgen"
> > >         * "fsl,ls1021a-clockgen"
> > >         Chassis-version clock strings include:
> > >         * "fsl,qoriq-clockgen-1.0": for chassis 1.0 clocks
> > >         * "fsl,qoriq-clockgen-2.0": for chassis 2.0 clocks
> > >
> > > I really hope we don't have to update every single fsl,<chip>-whatever binding
> > > every time a new chip comes out.  There are already other chips not listed,
> > > FWIW (e.g. t1040, t2080, ls1043a, and ls2080a).  That's why it says "such as".
> > 
> > If I remember correctly, DT maintainers want every supported compatible
> > string explicitly listed in bindings doc.  And they even added a check
> > into checkpatch.pl with commit bff5da433525 ("checkpatch: add DT
> > compatible string documentation checks").
> 
> See Documentation/devicetree/bindings/submitting-patches.txt:
> 
>   5) The wildcard "<chip>" may be used in compatible strings, as in
>      the following example:
> 
>          - compatible: Must contain '"nvidia,<chip>-pcie",
>            "nvidia,tegra20-pcie"' where <chip> is tegra30, tegra132, ...
> 
>      As in the above example, the known values of "<chip>" should be
>      documented if it is used.
> 
> It _is_ allowed to use the <chip> wildcard, and so you will not find all
> full compatible strings explicitly listed in bindings.  However, the
> chips themselves "should" be listed.

+ Rob and Mark

Oops, I'm not aware of this DT document.  In that case, the DT document
and checkpatch is basically asking for conflicting thing.  Rob, Mark,
can you guys please clarify?

Shawn



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