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;
From:   Vladimir Oltean <vladimir.oltean@nxp.com>
To:     Hongbo Wang <hongbo.wang@nxp.com>
CC:     Andrew Lunn <andrew@lunn.ch>, Hongjun Chen <hongjun.chen@nxp.com>,
        "shawnguo@kernel.org" <shawnguo@kernel.org>,
        Leo Li <leoyang.li@nxp.com>,
        "robh+dt@kernel.org" <robh+dt@kernel.org>,
        "linux-arm-kernel@lists.infradead.org" 
        <linux-arm-kernel@lists.infradead.org>,
        "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
        "f.fainelli@gmail.com" <f.fainelli@gmail.com>,
        "vivien.didelot@gmail.com" <vivien.didelot@gmail.com>,
        "davem@davemloft.net" <davem@davemloft.net>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Michael Walle <michael@walle.cc>,
        Xiaoliang Yang <xiaoliang.yang_1@nxp.com>
Subject: Re: [PATCH v1] arm64: dts: fsl: ls1028a-rdb: Add dts file to choose
 swp5 as dsa master
Thread-Topic: [PATCH v1] arm64: dts: fsl: ls1028a-rdb: Add dts file to choose
 swp5 as dsa master
Thread-Index: AQHYwWloKW9cDE/UY0+p0/SQtViTdQ==
Date:   Mon, 5 Sep 2022 20:52:27 +0000
Message-ID: <20220905205226.hwrnjx6qnrkdjw76@skbuf>
References: <20210813030155.23097-1-hongbo.wang@nxp.com>
 <YRZvItRlSpF2Xf+S@lunn.ch>
 <VI1PR04MB56773CC01AB86A8AA1A33F9AE1FA9@VI1PR04MB5677.eurprd04.prod.outlook.com>
 <20210813140745.fwjkmixzgvikvffz@skbuf>
 <VI1PR04MB56777E60653203A471B9864EE1FD9@VI1PR04MB5677.eurprd04.prod.outlook.com>
 <20210816174803.k53gqgw45hda7zh2@skbuf>
 <VI1PR04MB5677BA91547DC2228F615CEFE1FE9@VI1PR04MB5677.eurprd04.prod.outlook.com>
In-Reply-To: <VI1PR04MB5677BA91547DC2228F615CEFE1FE9@VI1PR04MB5677.eurprd04.prod.outlook.com>
Accept-Language: en-US
Content-Language: en-US
x-ms-exchange-antispam-messagedata-chunkcount: 1
x-ms-exchange-antispam-messagedata-0: =?us-ascii?Q?owtm7P1dG4UBrhRR/vIf/f3V0J9cLDlIFBZaR+Or+2t2+0iE3virZx8PzHYH?=
 =?us-ascii?Q?q3iEb0ejgRRwXpQbki5G0a7GUElKKA/SJve9zUzywWUtYQ5XXbIoFWrI4pt6?=
 =?us-ascii?Q?EG1+hyZN6qA5n05jrM7a5WsWzmt6Ss5wCYiV+dehIf/f2mbGqXA8iN3pC+OG?=
 =?us-ascii?Q?0hUmsyCezxBR6usRK9ZOAZ4tf8WHmzPeVMUQSMFREKjqMU9PmmRkeCWmxtsB?=
 =?us-ascii?Q?pcyyEU3i567pjYXAkWEfZeSaRs1mHJUR9xUrF6lUnzP9GzCNrA2uzDJkMdVI?=
 =?us-ascii?Q?jl6XOYe2HxONm8uUtraRjj3gZ97TC1e4zTYthPDSwwq6Po+kgeLcozRifexL?=
 =?us-ascii?Q?Pdcijgq9ySsb5FLkpdElenxIEYjCf+L6qioFjqjt47I/CeHR0Ct7+ALJCOEi?=
 =?us-ascii?Q?nP43wSLRjK78thrN+JG+goFz7Sb3wAUHmlP5k2JDNm4gG6i9NfQSwNR3wxIx?=
 =?us-ascii?Q?6ojpw1MahnBc1Kyn/i0Qzem1Z8nemBNmi3ahRdTDLkrBVIPbercobFWKAuTd?=
 =?us-ascii?Q?dCWJZcXhZ8IjU5fJXmRYCTNJH+XiHPqKRlIR6wdynVfdPuBnfeSPLtLqmWgv?=
 =?us-ascii?Q?H+XTlnhSVc5n8LW/zUFYNi3s63S8R8SZtR42oZtN/xK1IKjmfi5Mk8yJ2Q01?=
 =?us-ascii?Q?IPaqCPChra+J4GvXBmkqWAbHzO57KKvdHMOKWovKlVapPwdZzRyJmVgozjaG?=
 =?us-ascii?Q?PFDT1VciapHwe3z8kNx/XPEVDrkSZlJul/HhCQrdg2O8XImSoJxqSV2jdFdP?=
 =?us-ascii?Q?mfTTvQFbALZWekNY7TzEMUAvkwC5ZeCRS2qxCuztmBRRiilT3S7VwX3PGCr+?=
 =?us-ascii?Q?kLuKALBVgfmpHrAs0jI8S0b1QOaKNMdaZ/YxoY78LE6N07oNP4P2CQ24eCE+?=
 =?us-ascii?Q?YZBPllcIXtDjzkpvHp8tEYAXMZr34VEP2/WjY4GkPbIOcgIuCJiDM1TVbkUx?=
 =?us-ascii?Q?dSVA3N4EKlntUjAl95UjlknHRWNC8K6ap1bNEXG+Mc2CIfiqZOp4LnOl002m?=
 =?us-ascii?Q?lLXzR3kTHIslScaC/ldWi8Z6Gt7I45t2whJAC6eJ+ZMPJ9WnKqeWJ0o7zw+3?=
 =?us-ascii?Q?TyK1cadt6FJNZsuXWF4yflXwabGpaikmBI1QenbF/bq/p00izieP27+vFvC4?=
 =?us-ascii?Q?lFabckTITODhgvvEncbJ1T7caS8Kyep7uZuRev/ijPWy5qS/CAjB2BNsB4AK?=
 =?us-ascii?Q?cbh4EeFCPckk6tUFYSx+RX+40+17/V/LxOeo5RIcRP4U22YgdVDxm36JKHIE?=
 =?us-ascii?Q?Qi5R5VN7CHLH/mvBXjFWsM0OtIzVXmi3VrcICey+OFdgSpTkb/fjNH3zsHTo?=
 =?us-ascii?Q?/PL9tCIC4MaailoS6RjlTbAwmZpHAdpgptMWiMCO+MmoHHAvJrsQEPqXrTv/?=
 =?us-ascii?Q?yuFqJSJCujJ+w7Elo+kt4mmM0eRKCme5lqBs+Q+I0Dur0jZwzY6MDs0+x0LM?=
 =?us-ascii?Q?Z46n+uBa5oZTnr1yO1F14V/VFQrhyVTOROGsspicHkbfXgyzMFuKJjg3WzvQ?=
 =?us-ascii?Q?iVeidI8NeYa6NGqOsJlWb29Dx67ciW5KnfF4DTKQ4hf10hpINtNuyLz01Nmm?=
 =?us-ascii?Q?gvogWDrsoj5+mg6IxLc6U8v0nW+JPTVyxUzrh/WDL7AazP3l7aHiJZ/SQnZC?=
 =?us-ascii?Q?GA=3D=3D?=
Content-Type: text/plain; charset="us-ascii"
Content-ID: <0C0A912967F37F47813983FCA495E747@eurprd04.prod.outlook.com>
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
X-OriginatorOrg: nxp.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-AuthSource: VI1PR04MB5136.eurprd04.prod.outlook.com
X-MS-Exchange-CrossTenant-Network-Message-Id: 3aabef84-bd1d-44a6-7c02-08da8f808afa
X-MS-Exchange-CrossTenant-originalarrivaltime: 05 Sep 2022 20:52:27.5978
 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Hosted
X-MS-Exchange-CrossTenant-id: 686ea1d3-bc2b-4c6f-a92c-d99c5c301635
X-MS-Exchange-CrossTenant-mailboxtype: HOSTED
X-MS-Exchange-CrossTenant-userprincipalname: mADYoS/snccJ6XsOFQYxEGhRyiLtaMrU4nWh+AMcUZjGzo714XUUq7+y/0SyhhZ52XM2rGkVvaJ/hVXn7PLKUw==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: DB7PR04MB4378
X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED,
        DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE,
        RCVD_IN_MSPIKE_H2,SPF_HELO_PASS,SPF_PASS,T_SCC_BODY_TEXT_LINE
        autolearn=ham autolearn_force=no version=3.4.6
X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on
        lindbergh.monkeyblade.net
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Tue, Aug 17, 2021 at 02:59:07AM +0000, Hongbo Wang wrote:
> > On Mon, Aug 16, 2021 at 06:03:52AM +0000, Hongbo Wang wrote:
> > > > I was going to suggest as an alternative to define a device tree
> > > > overlay file with the changes in the CPU port assignment, instead o=
f
> > > > defining a wholly new DTS for the LS1028A reference design board.
> > > > But I am pretty sure that it is not possible to specify a
> > > > /delete-property/ inside a device tree overlay file, so that won't =
actually work.
> > >
> > > hi Vladimir,
> > >
> > >   if don't specify "/delete-property/" in this dts file, the
> > > corresponding dtb will not work well, so I add it to delete 'ethernet=
' property
> > > from mscc_felix_port4 explicitly.
> >
> > Judging by the reply, I am not actually sure you've understood what has=
 been
> > said.
> >
> > I said:
> >
> > There is an option to create a device tree overlay:
> >
> > https://www.kernel.org/doc/html/latest/devicetree/overlay-notes.html
> >
> > We use these for the riser cards on the LS1028A-QDS boards.
> >
> > https://source.codeaurora.org/external/qoriq/qoriq-components/linux/tre=
e/ar
> > ch/arm64/boot/dts/freescale/fsl-ls1028a-qds-13bb.dts?h=3DLSDK-20.12-V5.=
4
> >
> > They are included as usual in a U-Boot ITB file:
> >
> > / {
> >       images {
> >               /* Base DTB */
> >               ls1028aqds-dtb {
> >                       description =3D "ls1028aqds-dtb";
> >                       data =3D /incbin/("arch/arm64/boot/dts/freescale/=
fsl-ls1028a-qds.dtb");
> >                       type =3D "flat_dt";
> >                       arch =3D "arm64";
> >                       os =3D "linux";
> >                       compression =3D "none";
> >                       load =3D <0x90000000>;
> >                       hash@1 {
> >                               algo =3D "crc32";
> >                       };
> >               };
> >               /* Overlay */
> >               fdt@ls1028aqds-13bb {
> >                       description =3D "ls1028aqds-13bb";
> >                       data =3D /incbin/("arch/arm64/boot/dts/freescale/=
fsl-ls1028a-qds-13bb.dtb");
> >                       type =3D "flat_dt";
> >                       arch =3D "arm64";
> >                       load =3D <0x90010000>;
> >               };
> >       };
> > };
> >
> > In U-Boot, you apply the overlay as following:
> >
> > tftp $kernel_addr_r boot.itb && bootm
> > $kernel_addr_r#ls1028aqds#ls1028aqds-13bb
> >
> > It would have been nice to have a similar device tree overlay that chan=
ges the
> > DSA master from eno2 to eno3, and for that overlay to be able to be app=
lied
> > (or not) from U-Boot.
> >
> > But it's _not_ possible, because you cannot put the /delete-property/ (=
that you
> > need to have) in the .dtbo file. Or if you put it, it will not delete t=
he property
> > from the base dtb.
> >
> > That's all I said.
>=20
> thanks for the detailed explanation,
> I have got your point.
>=20
> thanks,
> hongbo

I'm replying to a very old topic here, but I don't think this made too
much progress (NXP still carries a downstream fsl-ls1028a-rdb-dsa-swp5-eno3=
.dts,
for a use case which is valid: using one of the 2 internal Ethernet
ports between the switch and the SoC as a plain data port, rather than a
CPU port).

I've found what I think is a satisfactory solution for myself. Rather
than carrying an entirely new device tree just to move around the DSA
master from &enetc_port2 to &enetc_port3, I'm building upon the changes
for multiple CPU ports which Shawn has accepted now.
https://lore.kernel.org/linux-arm-kernel/20220831160124.914453-1-olteanv@gm=
ail.com/

With that patch set, what Hongbo tried to add here simply becomes:

&mscc_felix_port4 {
	/delete-property/ ethernet;
};

I've already expressed discontent with the fact that it isn't possible
to move just this action to a device tree overlay and apply it to
whatever LS1028A based board, not just the RDB. However, I found that it
is possible to do this instead, just from within the U-Boot shell:

fdt addr $fdt_addr_r
fdt rm /soc/pcie@1f0000000/ethernet-switch@0,5/ports/port@4 ethernet
...
bootm $kernel_addr_r - $fdt_addr_r

which is even more convenient, because this way, the board device trees
now don't even need to be compiled with the dtc "-@" option (to include
the __symbols__ node required for dtb overlays).

It's likely that some of the people copied here do fancier tricks with
dynamic editing of the FDT already, on a day by day basis. In that case,
what can I say, have a good rest of the day ;)=