From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from www530.your-server.de (www530.your-server.de [188.40.30.78]) (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 C6D9C481A1; Thu, 25 Jan 2024 11:55:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=188.40.30.78 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706183721; cv=none; b=rhHBZJnu2y3drFaih2kwuOrO3kybplYyV8mDwadIndio+xDVSJHrH8xYRFcBPbY+oiq0NPbIZ0z22ailTowuFA+OzqGKwN8InElbioSh3IuYBkRXju9OzwC4hu0Eu+wDcdsOzdndU7IIiGnZ/+ve38daapiIvO6KwbYujIfh5SU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706183721; c=relaxed/simple; bh=0/KtXWM+5DW4c3nEA6ICqAjrU+Do2pgeS89POdOEYsU=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=ULboprvX/U9H4zetJ4oH+ZBGrjpG+LBWevot5BO9T0KtRV8S8ZIjE+faSUtVyhbSP4Y/Y20Q0Lz4v5KBeczLwkspvQrFC1I+RJfmNM84YY/KG/HlW3hedmRDJPGrRPkBNPqoG2Hd0nCEuyh0GnhSYb24/hdLlajjxuf/+ygLhzc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=geanix.com; spf=pass smtp.mailfrom=geanix.com; dkim=pass (2048-bit key) header.d=geanix.com header.i=@geanix.com header.b=LaukGkcs; arc=none smtp.client-ip=188.40.30.78 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=geanix.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=geanix.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=geanix.com header.i=@geanix.com header.b="LaukGkcs" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=geanix.com; s=default2211; h=Content-Type:MIME-Version:Message-ID:Date:References: In-Reply-To:Subject:Cc:To:From:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID; bh=19ahVdd1QUjj/gfp0rYesJtgcE+kp9SEnJVob0r94EQ=; b=LaukGkcsHzUeZW5NLj7IJXgzZQ ivjUU2g1KQCVPUuKm5qDxbGQvetBPb73CVDN4mQNYEnQNvrP1dRPzOV5Rs2ShqH6WrDH4BZEyD8p/ c81ueGK+idmgdWov8udfud6RWRhovZmbEzA2sBSF+TaAF7OMDsdP4uMM9JaYjBD38T9mOczg85XL5 eR8wYzvyI4Pavou9vASfNoQQ9+rzR21yrH+yXG7Gm4HDFC0Dm5S38YuF0kXQfykGaFoEL21Jxb94X c5zURftVO4Ol71NqI/rRMUJJjAcSy+6/z3aRKMn9mHjj6XLzOAE92eZrHNuPZ3VkwzEmnlVKgQ2GP gtD11bJw==; Received: from sslproxy03.your-server.de ([88.198.220.132]) by www530.your-server.de with esmtpsa (TLS1.3) tls TLS_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1rSyK9-0000LM-ID; Thu, 25 Jan 2024 12:55:13 +0100 Received: from [185.17.218.86] (helo=localhost) by sslproxy03.your-server.de with esmtpsa (TLSv1.3:TLS_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1rSyK8-000MDh-Ot; Thu, 25 Jan 2024 12:55:12 +0100 From: esben@geanix.com To: Krzysztof Kozlowski Cc: Conor Dooley , 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 In-Reply-To: <3adf7908-be27-4125-ae5b-6f2eb6100304@linaro.org> (Krzysztof Kozlowski's message of "Thu, 25 Jan 2024 10:19:45 +0100") References: <30ce8f45b8752c603acc861ebb2f18d74d2f8a07.1706105494.git.esben@geanix.com> <20240124-reptilian-icing-a95b20f123be@spud> <87bk99hj7q.fsf@geanix.com> <3adf7908-be27-4125-ae5b-6f2eb6100304@linaro.org> Date: Thu, 25 Jan 2024 12:55:12 +0100 Message-ID: <877cjxhbkv.fsf@geanix.com> User-Agent: Gnus/5.13 (Gnus v5.13) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain X-Authenticated-Sender: esben@geanix.com X-Virus-Scanned: Clear (ClamAV 0.103.10/27165/Thu Jan 25 10:51:15 2024) Krzysztof Kozlowski writes: > On 25/01/2024 10:10, esben@geanix.com wrote: >> Conor Dooley writes: >> >>> 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 the >>>> 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? >> >> 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. >> >>> If support is per controller is it not sufficient to use the >>> compatible to determine if this is supported? >> >> 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. Understood. >> 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... 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. But that is another story. I will respin the patch according to Conor's suggestion. /Esben