From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from metis.whiteo.stw.pengutronix.de (metis.whiteo.stw.pengutronix.de [185.203.201.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C3A7B2853F8 for ; Wed, 3 Dec 2025 10:16:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.203.201.7 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764757013; cv=none; b=Fs4tS3Whbo+0mGHaYCVSxVMr+1bY1Rl/caoJcSLjr1hNekQVMCQ8xdOFpNsxKC1XtY57HAIogX1qQPabrN3uIYiL2tAzzY766A2OX/UpzMSnSt9vLj7zZ+cLKzeWUvGAPv8B35iVHTnKZuQRsrd8qgN9x30H9an0ZEz3KGqKCkw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764757013; c=relaxed/simple; bh=nTdmeduMeqbHHtbwT6crN5Jg7zxo1zHTV0LmN6egeO0=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=O3bY0W5zfPk7Gqsi4+hCBZNuZdc9wK+a4oe+AT7f0nSM8Q1um1CzAEI8QZBbyoYa52KMUr7XVtKzpNGM7ElLnn7dNousYA2UUKkxNvU8dtiggDWEQ1MKAxQDO4iqmpUEdqoxMrckhad1EhNyzBnAMHvuWIEhXwl/VaKbdiiSfBY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de; spf=pass smtp.mailfrom=pengutronix.de; arc=none smtp.client-ip=185.203.201.7 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pengutronix.de Received: from ptz.office.stw.pengutronix.de ([2a0a:edc0:0:900:1d::77] helo=[127.0.0.1]) by metis.whiteo.stw.pengutronix.de with esmtp (Exim 4.92) (envelope-from ) id 1vQjuf-0006EP-MF; Wed, 03 Dec 2025 11:16:45 +0100 Message-ID: Date: Wed, 3 Dec 2025 11:16:44 +0100 Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: SoC-specific device tree aliases? To: Krzysztof Kozlowski , Rob Herring Cc: Sascha Hauer , "devicetree@vger.kernel.org" , Conor Dooley , devicetree-spec@vger.kernel.org, quentin.schulz@cherry.de, Marc Kleine-Budde , "kernel@pengutronix.de" , Krzysztof Kozlowski References: <58816b68-3b09-4320-9a4e-09f2c2b2d0fa@kernel.org> <8ce701c9-6c8d-4b3e-8706-760b8aba89fc@kernel.org> <20251117-smooth-spiked-loon-52df28-mkl@pengutronix.de> <576a9eae-7dba-47d0-ad66-0a81d1893271@kernel.org> <9e14fb8e-af84-4072-b0ac-9ead882782be@kernel.org> <07ee3540-d0c1-436e-9e1d-db1952f609a6@kernel.org> From: Ahmad Fatoum Content-Language: en-US, de-DE, de-BE In-Reply-To: <07ee3540-d0c1-436e-9e1d-db1952f609a6@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 2a0a:edc0:0:900:1d::77 X-SA-Exim-Mail-From: a.fatoum@pengutronix.de X-SA-Exim-Scanned: No (on metis.whiteo.stw.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: devicetree@vger.kernel.org Hello Krzysztof, On 11/17/25 5:29 PM, Krzysztof Kozlowski wrote: > On 17/11/2025 17:06, Rob Herring wrote: >>> So you want it to be an ABI for barebox, sure, just make it a binding. >> >> What do you have in mind? Other than standard names for the aliases, >> what can we check here? That a specific alias points to a specific >> path? That would be a bit too much IMO. That would be equivalent to >> specifying possible values in 'reg' for all devices. > > Binding with pattern or list of needed alias names, referenced by given > soc-platform top-level schema. > > One of the points is to make it explicit and obvious (e.g. to Arnd or to > me if I forget, because I follow the same logic of aliases per board) > that these aliases are used outside of kernel. > > Just because ufs/mmc/spi can be used that way, does not mean we should > accept any possible alias into soc.dtsi. I can't see how this could work. A number of boards renumber MMC devices in a different manner than the SoC reference manual: - Changing the alias numbering is an ABI break, because Linux derives its /dev/mmcblkX numbering from it - Leaving them as-is means they are not usable for boot source determination That's why I am suggesting a separate node that reflects only the SoC reference manual's numbering. I don't see how a schema for the existing /aliases would remove the need for this. Thanks, Ahmad > > Best regards, > Krzysztof > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |