From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 CF38113173F; Thu, 25 Jan 2024 17:15:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706202901; cv=none; b=asiRPTMshk5PCqoj45SfEjGxqJNJe+SbTlN7qdzgsW6ZY/unm4tmr9OpGKQxAz4ZFQ07pDd9kN8Lv5IMZKKj3F7Q7x5Xz+WngAY8Lztgka6enOnjskFGdWTDbpJT5yIsn/03iWwAfQtKRZkqLgGGftre59TUHAyH5uwMdyn4SVA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706202901; c=relaxed/simple; bh=3dVf+vPXIdsPQhadKBnqSmffUhDAz2vQfQH/Y8KghKo=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=jH+e6bjtG2eUB+YcB2SbFZJIGI/CKirqZ15gJ7TbwH/2LljRJXw8hdWEw0kAn49su8BlOTpaLAUpZu7ul7cH5UyEe8c3f8an7lHaPLMhQSAzeIGj1P3mCMViHR2tDSWFI3V3IHvgwEqDk7/K4HC7pJ3q+I+CG3/GJGtZSoAUBEA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Txkf3O/b; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Txkf3O/b" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2FB71C433C7; Thu, 25 Jan 2024 17:14:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1706202901; bh=3dVf+vPXIdsPQhadKBnqSmffUhDAz2vQfQH/Y8KghKo=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Txkf3O/bU+w3xpkbVkgMMl8QUXBKPsrBmaVGJ73PJStKMIRdZZqS1btShnlKYSe4B 3tWxt+neitpkeD6DPTmPIUV6ZB93graF8xd+2W1FuoHqZVfe3h0vR4YjO2jucAzK5y 2apRC9G275s0VAckQ1rnOTKJLj8fI2J5p5OR32uU3NdIO0LvfNUgaLt0gBUvnsSowf plXpjO3La7ab9VYy8UASERjMOsLZ1L1jr8FdGdOFn5MP6r47IiDue4UFNF7/j8k4Zx ImdM51iNoWJfm+COzc+RPfgZT6UUCi5JAPHOGVraofBaXE5VDj5vhVyLzUjZFsjSlY S2yjAiaTH/QFA== Date: Thu, 25 Jan 2024 17:14:55 +0000 From: Conor Dooley To: esben@geanix.com Cc: Krzysztof Kozlowski , devicetree@vger.kernel.org, "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Alexandre Torgue , Giuseppe Cavallaro , Jose Abreu , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/3] dt-bindings: net: snps,dwmac: Add time-based-scheduling property Message-ID: <20240125-pebble-reproach-f550d00a2abb@spud> References: <30ce8f45b8752c603acc861ebb2f18d74d2f8a07.1706105494.git.esben@geanix.com> <20240124-reptilian-icing-a95b20f123be@spud> <87bk99hj7q.fsf@geanix.com> <3adf7908-be27-4125-ae5b-6f2eb6100304@linaro.org> <877cjxhbkv.fsf@geanix.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="AsbEPBmbmpQjmWgj" Content-Disposition: inline In-Reply-To: <877cjxhbkv.fsf@geanix.com> --AsbEPBmbmpQjmWgj Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Jan 25, 2024 at 12:55:12PM +0100, esben@geanix.com wrote: > Krzysztof Kozlowski writes: >=20 > > On 25/01/2024 10:10, esben@geanix.com wrote: > >> Conor Dooley writes: > >>=20 > >>> On Wed, Jan 24, 2024 at 03:33:06PM +0100, Esben Haabendal wrote: > >>>> Time Based Scheduling can be enabled per TX queue, if supported by t= he > >>>> controller. > >>> > >>> If time based scheduling is not supported by the controller, then the > >>> property should not be present! The presence of a property like this > >>> should mean that the feature is supported, using it is up to the > >>> operating system. > >>> > >>> That said, why is this a property that should be in DT? > >>=20 > >> It is added to the tx-queues-config object of snps,dwmac bindings. This > >> entire object is about configuration of the ethernet controller, which > >> is also what the purpose of the snps,time-based-scheduling. > >> So yes, it is not specifically about describing what the hardware is > >> capable of, but how the hardware is configured. It is a continuation of > >> the current driver design. > >>=20 > >>> If support is per controller is it not sufficient to use the > >>> compatible to determine if this is supported? > >>=20 > >> Are you suggesting to include the mapping from all supported compatible > >> controllers to which TX queues supports TBS in the driver code? What > >> would the benefit of that compared to describing it explicitly in the > >> binding? > > > > The benefit is complying with DT bindings rules, saying that bindings > > describe hardware pieces, not drivers. >=20 > Understood. >=20 > >> And for the purpose of the above question, I am talking about it as if > >> the binding was describing the hardware capability and not the > >> configuration. > > > > "if"? You wrote it is for driver design... >=20 > If you look at the current driver, all the devicetree bindings under > rx-queues-config and tx-queues-config are violating the DT binding > rules. > Cleaning up that requires quite some work and I guess will break > backwards compatibility to some extend. Let bygones be bygones. If something undesirable got in previously, breaking backwards compatibility there is not justified IMO. --AsbEPBmbmpQjmWgj Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQRh246EGq/8RLhDjO14tDGHoIJi0gUCZbKXDwAKCRB4tDGHoIJi 0mZmAP9R7uQLuENcaLcze3yAlLCBg7nWplWJaCgWwS4IRXlV9gEAjX3MUDAdIDcP ALEQkpPnRg6hiT9y1JmMSKxla8Uclwg= =Q2qx -----END PGP SIGNATURE----- --AsbEPBmbmpQjmWgj--