LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
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>,
	Po Liu <po.liu@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>
Subject: Re: [EXT] Re: [PATCH v1] arm64: dts: fsl: ls1028a-rdb: Add dts file to choose swp5 as dsa master
Date: Mon, 16 Aug 2021 17:48:03 +0000	[thread overview]
Message-ID: <20210816174803.k53gqgw45hda7zh2@skbuf> (raw)
In-Reply-To: <VI1PR04MB56777E60653203A471B9864EE1FD9@VI1PR04MB5677.eurprd04.prod.outlook.com>

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 of 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/tree/arch/arm64/boot/dts/freescale/fsl-ls1028a-qds-13bb.dts?h=LSDK-20.12-V5.4

They are included as usual in a U-Boot ITB file:

/ {
	images {
		/* Base DTB */
		ls1028aqds-dtb {
			description = "ls1028aqds-dtb";
			data = /incbin/("arch/arm64/boot/dts/freescale/fsl-ls1028a-qds.dtb");
			type = "flat_dt";
			arch = "arm64";
			os = "linux";
			compression = "none";
			load = <0x90000000>;
			hash@1 {
				algo = "crc32";
			};
		};
		/* Overlay */
		fdt@ls1028aqds-13bb {
			description = "ls1028aqds-13bb";
			data = /incbin/("arch/arm64/boot/dts/freescale/fsl-ls1028a-qds-13bb.dtb");
			type = "flat_dt";
			arch = "arm64";
			load = <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
changes the DSA master from eno2 to eno3, and for that overlay to be
able to be applied (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 the property from the base dtb.

That's all I said.

  reply	other threads:[~2021-08-16 17:48 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-08-13  3:01 hongbo.wang
2021-08-13 13:09 ` Andrew Lunn
2021-08-13 13:56   ` [EXT] " Hongbo Wang
2021-08-13 14:07     ` Vladimir Oltean
2021-08-13 14:25       ` Andrew Lunn
2021-08-16  6:03       ` Hongbo Wang
2021-08-16 17:48         ` Vladimir Oltean [this message]
2021-08-17  2:59           ` Hongbo Wang

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210816174803.k53gqgw45hda7zh2@skbuf \
    --to=vladimir.oltean@nxp.com \
    --cc=andrew@lunn.ch \
    --cc=davem@davemloft.net \
    --cc=devicetree@vger.kernel.org \
    --cc=f.fainelli@gmail.com \
    --cc=hongbo.wang@nxp.com \
    --cc=hongjun.chen@nxp.com \
    --cc=leoyang.li@nxp.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=po.liu@nxp.com \
    --cc=robh+dt@kernel.org \
    --cc=shawnguo@kernel.org \
    --cc=vivien.didelot@gmail.com \
    --subject='Re: [EXT] Re: [PATCH v1] arm64: dts: fsl: ls1028a-rdb: Add dts file to choose swp5 as dsa master' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).