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 428D5C433EF for ; Thu, 28 Apr 2022 13:33:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347249AbiD1Ngb (ORCPT ); Thu, 28 Apr 2022 09:36:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36934 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347245AbiD1Nga (ORCPT ); Thu, 28 Apr 2022 09:36:30 -0400 Received: from mail-oa1-f45.google.com (mail-oa1-f45.google.com [209.85.160.45]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B914C36322; Thu, 28 Apr 2022 06:33:15 -0700 (PDT) Received: by mail-oa1-f45.google.com with SMTP id 586e51a60fabf-deb9295679so5152508fac.6; Thu, 28 Apr 2022 06:33:15 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=MkPYC4wT6c/VEzdCj0wFf0XUJgHVgHaxvf4ri5zul6g=; b=RcZtELW2TcWDRKSRKXL4rsuZjl//w0sXHcz4x8N1xAf/r5Sgvl6vDlIWOYEUAA/A7e EflF8wvwYREF9zLrFJDrsMWH4P105CviJsV6VhoRhneejW+z/f05PCZpWxfLlibiTz+k vf26WpkgR4/Ij6XNZ69nZbxmy7Fhrq0O4q8DMcLdkieesv6t/wGSrsnq3D46pnHMENqg c840KqJorlw7QHJaH5I4Q4E842DDgZFWI6kRBz1gn5U9CLP8tE4SbRlPZmToFDgKzdx6 e1D9bcRQMb7i+Eg9t0MB4Y2G/9yHBOS8aggQ7TDi7W/xKZltQ5L38KOGwX+lkFRRGaMA Szsg== X-Gm-Message-State: AOAM533YFPEyRItYvcta+DxKasXsgWamtl46/IRjcbFzBhoZCxi8ew1E iWdatBeSqBByqHffkLxzmQ== X-Google-Smtp-Source: ABdhPJyyg4xxehRJ6S6u/e8qGxKkazJCdf8F+SPH8Hd67CeOr+MmYpGdtq1tiHMic/2BoR0ZYp2jMQ== X-Received: by 2002:a05:6870:2187:b0:e9:7872:c7f6 with SMTP id l7-20020a056870218700b000e97872c7f6mr4563491oae.257.1651152795039; Thu, 28 Apr 2022 06:33:15 -0700 (PDT) Received: from robh.at.kernel.org (66-90-144-107.dyn.grandenetworks.net. [66.90.144.107]) by smtp.gmail.com with ESMTPSA id q22-20020a056870e89600b000e686d13895sm1819310oan.47.2022.04.28.06.33.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 28 Apr 2022 06:33:14 -0700 (PDT) Received: (nullmailer pid 2104457 invoked by uid 1000); Thu, 28 Apr 2022 13:33:13 -0000 Date: Thu, 28 Apr 2022 08:33:13 -0500 From: Rob Herring To: Krzysztof Kozlowski Cc: Marek Szyprowski , devicetree@vger.kernel.org, Dinh Nguyen , Lee Jones , Krzysztof Kozlowski , Sudeep Holla , Michal Simek , Lorenzo Pieralisi , Scott Branden , Sylwester Nawrocki , linux-samsung-soc@vger.kernel.org, Broadcom Kernel Team , linux-kernel@vger.kernel.org, Alim Akhtar , Liviu Dudau , Ray Jui , linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH 08/10] ARM: dts: exynos: use proper 'dma-channels/requests' properties Message-ID: References: <20220427155840.596535-1-krzysztof.kozlowski@linaro.org> <20220427155840.596535-9-krzysztof.kozlowski@linaro.org> <5eeac2a0-4293-675e-9dc2-25ed8ab3fb8f@samsung.com> <6981f93a-ef01-6ba0-4451-26526372d666@linaro.org> <05c908ce-217f-6938-6745-7405ac39d8ea@samsung.com> <1399774c-f188-81f1-4d15-367b9d0e4a59@linaro.org> <99c80fb6-c6cc-9370-b93d-ed736c7f2192@samsung.com> <813bd5f2-38b6-9642-6993-94ad78f5c08a@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <813bd5f2-38b6-9642-6993-94ad78f5c08a@linaro.org> Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Thu, Apr 28, 2022 at 12:09:02PM +0200, Krzysztof Kozlowski wrote: > On 28/04/2022 12:05, Marek Szyprowski wrote: > >>>>> I also don't see any code that would read those properties. IMHO they > >>>>> should be simply removed at all, at least for the PL330 related nodes. > >>>> In current Linux implementation they indeed are not used. Nothing parses > >>>> them. However: > >>>> 1. They describe (hopefully correct) the hardware. > >>>> 2. They might be used by other implementations of pl330 driver. > >>>> > >>>> I would not remove them from existing sources, but indeed maybe there is > >>>> no need to add for new files. > >>> What's the point in having dt properties duplicating data that might be > >>> read from the driver registers? > >> Hm, indeed, there is no point in this. Since they are read from > >> registers, what was the idea behind in commit 42cf20980cde? > > > > #dma-cells is indeed required, but the rest seems to be the cargo-cult > > of some kind. > > Rob, > > Any guidance from your side? Is there any benefit in describing the > hadrware (dma-channels/dma-requests) if the same value can be read from > registers? Drop the properties. They should only be an override if ever needed. Rob