From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8EDBAC43334 for ; Thu, 30 Jun 2022 18:27:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236577AbiF3S1r (ORCPT ); Thu, 30 Jun 2022 14:27:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42566 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236272AbiF3S1q (ORCPT ); Thu, 30 Jun 2022 14:27:46 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 11345427CA for ; Thu, 30 Jun 2022 11:27:46 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id B5BCCB82CA3 for ; Thu, 30 Jun 2022 18:27:44 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 20225C34115; Thu, 30 Jun 2022 18:27:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1656613663; bh=vZlB4QRdgWqHZDNuidk5DViD5LF3+fh0M8zHRrvX+vI=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=IBbDCSwRRUEEUh9gT3PZW1hZuVIvz5fC0LHk1yJNa7iHf8iI5cqOe4w81fZ+hT+cA QfND6rQWN62H1+5tp7jfoFjQxzFU5FAEzonr/V7ch2FdUOm02LRg7cbN83kCg35vlq /Nu8oUmhPTc8mFyO4yyiHB7VU0NhAh1nYaqIahiU6h/ogWix+fNznTlZ+SaM3bePTz w1lkAa2mrr2vzxDtOSa1QI/Jb65BjOexsN617xxMwiIkh6w9ZtVP1P97wM920n13TP PkWls/drDrgpG/5lSjCHSTnvNgO2nMaWMpi/5SUKDI5NB4WelZbhOPHkUT+drRBhWF +YZ/xnEmlDX5g== Date: Thu, 30 Jun 2022 11:27:42 -0700 From: Jakub Kicinski To: Vadim Fedorenko Cc: "Kubalewski, Arkadiusz" , Vadim Fedorenko , Aya Levin , "netdev@vger.kernel.org" , Jonathan Lemon , linux-arm-kernel@lists.infradead.org, Richard Cochran Subject: Re: [RFC PATCH v1 1/3] dpll: Add DPLL framework base functions Message-ID: <20220630112742.0a1d0bf0@kernel.org> In-Reply-To: <689711e9-47ca-af2d-b0a7-a6406d9736e1@novek.ru> References: <20220623005717.31040-1-vfedorenko@novek.ru> <20220623005717.31040-2-vfedorenko@novek.ru> <34093244-431b-98c8-ba88-82957c659808@novek.ru> <528be46d-16d4-bf71-a657-8e7fd55f9ebd@novek.ru> <20220629192312.45acd2fd@kernel.org> <689711e9-47ca-af2d-b0a7-a6406d9736e1@novek.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Thu, 30 Jun 2022 16:50:46 +0100 Vadim Fedorenko wrote: > On 30.06.2022 03:23, Jakub Kicinski wrote: >> On Thu, 30 Jun 2022 00:30:08 +0100 Vadim Fedorenko wrote: >>> This way it's getting closer and closer to ptp, but still having phase offset is >>> fair point and I will go this way. Jakub, do you have any objections? >> >> How does the DPLL interface interact with PTP? Either API can set the >> phase. > > Well, if the same hardware is exposed to both subsystem, it will be serialised > by hardware driver. And it goes to hardware implementation on how to deal with > such changes. Am I wrong? That's what ends up happening in practice. But it's a pretty poor experience for everyone involved :( Stating the obvious, perhaps, but the goal should be that either the APIs are disjoint or one is a superset of the other and there can be a kernel translation layer so that the driver only has to implement one. By a quick look at the PTP header it has phase offsets for both the clock and the outputs? Not sure. Don't see much in the docs either.