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Date:   Tue, 9 Aug 2022 23:45:18 +0200
From:   Pali =?utf-8?B?Um9ow6Fy?= <pali@kernel.org>
To:     Tim Harvey <tharvey@gateworks.com>
Cc:     Sean Anderson <sean.anderson@seco.com>,
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        netdev <netdev@vger.kernel.org>, u-boot <u-boot@lists.denx.de>,
        Device Tree Mailing List <devicetree@vger.kernel.org>
Subject: Re: ethernet<n> dt aliases implications in U-Boot and Linux
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On Tuesday 09 August 2022 14:39:05 Tim Harvey wrote:
> I've been wondering the same as well which made me wonder what the
> history of the 'aliases' node is and why its not used in most cases in
> Linux. I know for the SOC's I work with we've always defined aliases
> for ethernet<n>, gpio<n>, serial<n>, spi<n>, i2c<n>, mmc<n> etc. Where
> did this practice come from and why are we putting that in Linux dts
> files it if it's not used by Linux?

U-Boot can modify on-the-fly Linux's DTB file when booting Linux kernel.
For example it can put permanent MAC address into ethernet nodes from
U-Boot env. Similarly it can modify other DT nodes.

So even when Linux itself does not use particular alias, it is used by
the bootloader.