Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Thu, 1 Dec 2022 17:44:00 -0600
From:   Rob Herring <robh@kernel.org>
To:     Pali =?iso-8859-1?Q?Roh=E1r?= <pali@kernel.org>
Cc:     Michael Ellerman <mpe@ellerman.id.au>,
        =?utf-8?B?QXLEsW7DpyDDnE5BTA==?= <arinc.unal@arinc9.com>,
        netdev@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
        Marek =?iso-8859-1?Q?Beh=FAn?= <kabel@kernel.org>
Subject: Re: [PATCH 5/5] powerpc: dts: remove label = "cpu" from DSA
 dt-binding
Message-ID: <20221201234400.GA1692656-robh@kernel.org>
References: <20221130141040.32447-1-arinc.unal@arinc9.com>
 <20221130141040.32447-6-arinc.unal@arinc9.com>
 <87a647s8zg.fsf@mpe.ellerman.id.au>
 <20221201173902.zrtpeq4mkk3i3vpk@pali>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
In-Reply-To: <20221201173902.zrtpeq4mkk3i3vpk@pali>
Precedence: bulk

On Thu, Dec 01, 2022 at 06:39:02PM +0100, Pali Rohár wrote:
> On Thursday 01 December 2022 21:40:03 Michael Ellerman wrote:
> > Arınç ÜNAL <arinc.unal@arinc9.com> writes:
> > > This is not used by the DSA dt-binding, so remove it from all devicetrees.
> > >
> > > Signed-off-by: Arınç ÜNAL <arinc.unal@arinc9.com>
> > > ---
> > >  arch/powerpc/boot/dts/turris1x.dts | 2 --
> > >  1 file changed, 2 deletions(-)
> > 
> > Adding Pali to Cc.
> > 
> > These were only recently updated in commit:
> > 
> >   8bf056f57f1d ("powerpc: dts: turris1x.dts: Fix labels in DSA cpu port nodes")
> > 
> > Which said:
> > 
> >   DSA cpu port node has to be marked with "cpu" label.
> > 
> > But if the binding doesn't use them then I'm confused why they needed to
> > be updated.
> > 
> > cheers
> 
> I was told by Marek (CCed) that DSA port connected to CPU should have
> label "cpu" and not "cpu<number>". Modern way for specifying CPU port is
> by defining reference to network device, which there is already (&enet1
> and &enet0). So that change just "fixed" incorrect naming cpu0 and cpu1.
> 
> So probably linux kernel does not need label = "cpu" in DTS anymore. But
> this is not the reason to remove this property. Linux kernel does not
> use lot of other nodes and properties too... Device tree should describe
> hardware and not its usage in Linux. "label" property is valid in device
> tree and it exactly describes what or where is this node connected. And
> it may be used for other systems.
> 
> So I do not see a point in removing "label" properties from turris1x.dts
> file, nor from any other dts file.

Well, it seems like a bit of an abuse of 'label' to me. 'label' should 
be aligned with a sticker or other identifier identifying something to a 
human. Software should never care what the value of 'label' is.

Rob