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 AF26BC433F5 for ; Thu, 13 Jan 2022 17:22:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232535AbiAMRW2 (ORCPT ); Thu, 13 Jan 2022 12:22:28 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48014 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232273AbiAMRW2 (ORCPT ); Thu, 13 Jan 2022 12:22:28 -0500 Received: from mail-wm1-x32a.google.com (mail-wm1-x32a.google.com [IPv6:2a00:1450:4864:20::32a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A04C8C061574 for ; Thu, 13 Jan 2022 09:22:27 -0800 (PST) Received: by mail-wm1-x32a.google.com with SMTP id p1-20020a1c7401000000b00345c2d068bdso5848097wmc.3 for ; Thu, 13 Jan 2022 09:22:27 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to; bh=m+qwgIpcnSvftGIeIBkTsoTpDXxQfAwlOlBwhtw/Z0A=; b=VJqNGlWQAxaBIHh+bH7oKdtbLyJ/aMcIoRj/Y1DXeG6CAXdz1xRWd/gZiUoLmdCevv u2sZhBE1mNQg5r7AwoYjYVhiFAR9Ey0+4b40w5GPHluuQkr6R5zBwJIUHDma6NACqMNo QwLeF0XbkE1DmYtxKcyDQtzafXDCtcsVYX7YaWqX95HLcn0qejJh+vOL7lhuAJsNR8c1 A53mKsBkqPLEEUot9MvSb5V/L6HvN/r7gPKhGZNcVRlmT5uEXGhE910n1XXe0wJfvPYC yMNJLrJfOTKphqflkdUidQlDTgvJNIoNpxwAxiJghGcUPEKuIuKhEBVgZ79Fz/gdisL1 LqhA== 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:content-transfer-encoding :in-reply-to; bh=m+qwgIpcnSvftGIeIBkTsoTpDXxQfAwlOlBwhtw/Z0A=; b=Xj68eghCgIDVQ5n9IbkQ8BHZNbJnB5TNtzp9taW0ULJL+M3WRR9Gl50BFO1wf2shTp tB7FiE3ituy7fgBMUK95Crjvwa1rCRhvp0HGxUPDP17jPC9ulMHaYZl200C0szLY2Cwr /9u5K7C3kw8oTTaBYL8QpVqTUemyxp73DEVZGVb6SNgxpNnmmvvXoIANFs2Nif4fVTGM ReprBrTkGmUyIjfp9angv5UrRPEsggfnWjoz38i3CytfF6ceeIVFarBFnOpFPPnNZ8EV UMI4SWjq06ElGc2m8pwUbhYdSX3Gt+Vq9hyBv6QtxABrVpibRUGsr/fvTmdaMHmiyKJe 99CA== X-Gm-Message-State: AOAM530TIGKSD3ldw+3ligg7ZeajKo93MyJyFJgqO3PI2Hu4vxBu9uHM wwrrFSs46lrOzAJp+4dvpoHVEw== X-Google-Smtp-Source: ABdhPJx/9n09U/8hRrDhCwuUWuzbmuTc5wAGJSYLhLjElpiJ9gMfV/CLNGtLeaRJo8W5ntJyTSDwPg== X-Received: by 2002:a7b:c4da:: with SMTP id g26mr4935862wmk.191.1642094546100; Thu, 13 Jan 2022 09:22:26 -0800 (PST) Received: from google.com ([31.124.24.179]) by smtp.gmail.com with ESMTPSA id p12sm7646216wms.43.2022.01.13.09.22.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 13 Jan 2022 09:22:25 -0800 (PST) Date: Thu, 13 Jan 2022 17:22:24 +0000 From: Lee Jones To: Zong Li Cc: Michael Turquette , Stephen Boyd , Palmer Dabbelt , Paul Walmsley , linux-clk , linux-riscv Subject: Re: [PATCH v3 RESEND] clk: sifive: Fix W=1 kernel build warning Message-ID: References: <20220107090715.2601-1-zong.li@sifive.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-clk@vger.kernel.org On Thu, 13 Jan 2022, Lee Jones wrote: > On Thu, 13 Jan 2022, Zong Li wrote: > > > On Wed, Jan 12, 2022 at 5:09 PM Lee Jones wrote: > > > > > > On Wed, 12 Jan 2022, Zong Li wrote: > > > > > > > On Tue, Jan 11, 2022 at 5:32 PM Lee Jones wrote: > > > > > > > > > > On Tue, 11 Jan 2022, Zong Li wrote: > > > > > > > > > > > On Mon, Jan 10, 2022 at 5:50 PM Lee Jones wrote: > > > > > > > > > > > > > > Please improve the subject line. > > > > > > > > > > > > > > If this is a straight revert, the subject line should reflect that. > > > > > > > > > > > > > > If not, you need to give us specific information regarding the purpose > > > > > > > of this patch. Please read the Git log for better, more forthcoming > > > > > > > examples. > > > > > > > > > > > > > > > > > > > It seems to me that this patch is not a straight revert, it provides > > > > > > another way to fix the original build warnings, just like > > > > > > '487dc7bb6a0c' tried to do. I guess the commit message has described > > > > > > what the original warnings is and what the root cause is, it also > > > > > > mentioned what is changed in this patch. I'm a bit confused whether we > > > > > > need to add fixes tag, it looks like that it might cause some > > > > > > misunderstanding? > > > > > > > > > > I think it's the patch description and subject that is causing the > > > > > misunderstanding. > > > > > > > > > > > > > Yes, the subject should be made better. > > > > > > > > > Please help me with a couple of points and I'll help you draft > > > > > something up. > > > > > > > > > > Firstly, what alerted you to the problem you're attempting to solve? > > > > > > > > > > > > > I recently noticed the code was changed, I guess that I was missing > > > > something there. After tracking the log, I found that there is a build > > > > warning in the original implementation, and it was already fixed, but > > > > it seems to me that there are still some situations there, please help > > > > me to see the following illustration. > > > > > > > > > > > > --- a/drivers/clk/sifive/fu540-prci.c > > > > > > > > +++ b/drivers/clk/sifive/fu540-prci.c > > > > > > > > @@ -20,7 +20,6 @@ > > > > > > > > > > > > > > > > #include > > > > > > > > > > > > > > > > -#include "fu540-prci.h" > > > > > > > > > > How is this related to the issue/patch? > > > > > > > > > > > > > Let's go back to the version without '487dc7bb6a0c' fix. The > > > > prci_clk_fu540 variable is defined in sifive-fu540-prci.h header, > > > > however, fu540-prci.c includes this header but doesn't use this > > > > variable, so the warnings happen. > > > > > > > > The easiest way to do it is just removing this line, then the warning > > > > could be fixed. But as the '487dc7bb6a0c' or this patch does, the code > > > > should be improved, the prci_clk_fu540 variable shouldn't be defined > > > > in the header, it should be moved somewhere. > > > > > > > > > > > > +struct prci_clk_desc prci_clk_fu540 = { > > > > > > > > + .clks = __prci_init_clocks_fu540, > > > > > > > > + .num_clks = ARRAY_SIZE(__prci_init_clocks_fu540), > > > > > > > > +}; > > > > > > > > > > > > > diff --git a/drivers/clk/sifive/fu540-prci.h b/drivers/clk/sifive/fu540-prci.h > > > > > > > > index c220677dc010..931d6cad8c1c 100644 > > > > > > > > --- a/drivers/clk/sifive/fu540-prci.h > > > > > > > > +++ b/drivers/clk/sifive/fu540-prci.h > > > > > > > > @@ -7,10 +7,6 @@ > > > > > > > > +extern struct prci_clk_desc prci_clk_fu540; > > > > > > > > > > > > > diff --git a/drivers/clk/sifive/sifive-prci.c b/drivers/clk/sifive/sifive-prci.c > > > > > > > > index 80a288c59e56..916d2fc28b9c 100644 > > > > > > > > --- a/drivers/clk/sifive/sifive-prci.c > > > > > > > > +++ b/drivers/clk/sifive/sifive-prci.c > > > > > > > > @@ -12,11 +12,6 @@ > > > > > > > > #include "fu540-prci.h" > > > > > > > > #include "fu740-prci.h" > > > > > > > > > > > > > > > > -static const struct prci_clk_desc prci_clk_fu540 = { > > > > > > > > - .clks = __prci_init_clocks_fu540, > > > > > > > > - .num_clks = ARRAY_SIZE(__prci_init_clocks_fu540), > > > > > > > > -}; > > > > > > > > - > > > > > > > > > > I'm not sure if it's you or I that is missing the point here, but > > > > > prci_clk_fu540 is used within *this* file itself: > > > > > > > > > > > > > Here is another situation I mentioned at the beginning, if we'd like > > > > to put prci_clk_fu540 here, prci_clk_fu740 should be put here as well. > > > > I guess you didn't do that because there is a bug in the original > > > > code, fu740-prci.c misused the fu540-prci.h, so there is no build > > > > warning on fu740. FU740 still works correctly by misusing the > > > > fu540-prci.h header because fu740-prci.c doesn't actually use the > > > > prci_clk_fu740 variable, like fu540 we talked about earlier. > > > > > > > > > static const struct of_device_id sifive_prci_of_match[] = { > > > > > {.compatible = "sifive,fu540-c000-prci", .data = &prci_clk_fu540}, > > > > > {.compatible = "sifive,fu740-c000-prci", .data = &prci_clk_fu740}, > > > > > {} > > > > > }; > > > > > > > > > > So why are you moving it out to somewhere it is *not* used and making > > > > > it an extern? This sounds like the opposite to what you'd want? > > > > > > > > The idea is that sifive-prci.c is the core and common part of PRCI, > > > > and I'd like to separate the SoCs-dependent part into SoCs-dependent > > > > files, such as fu540-prci.c and fu740-prci.c. The goal is if we add > > > > new SoCs in the future, we can just put the SoCs-dependent data > > > > structure in the new C file, and do as minimum modification as > > > > possible in the core file (i.e. sifive-prci.c). It might also help us > > > > to see all SoCs-dependent data in one file, then we don't need to > > > > cross many files. Putting these two variables in sifive-pric.c is the > > > > right thing to do, but that is why I separate them and make them > > > > extern in this patch. > > > > > > I can see what you are doing, but I don't think this is the right > > > thing to do. Please put the struct in the same location as it's > > > referenced. > > > > If we decide to move them into sifive-prci.c (i.e. put it in where > > it's referenced.), I worried that we might need to move all stuff > > which are in fu540-prci.c and fu740-prci.c. Because 'prci_clk_fu540' > > is referenced in sifive-prci.c, whereas '__prci_init_clocks_fu540' is > > used by 'prci_clk_fu540', and the almost things in fu540-prci.c are > > used by '__prci_init_clocks_fu540'. It seems to be a little bit > > difficult to clearly decouple it for modularization which I want to > > do. What this patch does might be a accepted way, I hope that you can > > consider it again. > > > > > > > > And yes that should also be the case for prci_clk_fu740 and yes, it > > > was over-looked because it wasn't causing warnings at build time for > > > whatever reason. > > > > > > IMHO, placing 'struct of_device_id' match tables in headers is also > > > odd and is likely the real cause of this strange situation. > > > > I couldn't see what are you pointing, do you mind give more details > > about it? It seems to me that the match table is put in C file (i.e. > > sifive-prci.c). > > Oh, sorry, it's a common source file, rather than a header. > > Okay, so I went and actually looked at the code this time. > > If I were you I would move all of the device specific structs and > tables into the device specific header files, then delete the device > specific source (C) files entirely. > > There seems to be no good reason for carrying a common source file as > well as a source file AND header file for each supported device. > IMHO, that's over-complicating things for no apparent gain. I can even do it for you, if you'd like! -- Lee Jones [李琼斯] Principal Technical Lead - Developer Services Linaro.org │ Open source software for Arm SoCs Follow Linaro: Facebook | Twitter | Blog