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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 490F2C433F5 for ; Sun, 20 Mar 2022 18:49:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=gWhX/XFh5u1cFT1SMydDnqsKOhhINTiDha+g9PlzycY=; b=A5AooxGNDrbeqe 9Igexv/AVL9NqlWkwn6+sXXPGFUp89bBcIG4qo9ViZrVO/XFNkZ9DVClH8TYlwKjJEArNwFYDJsGf 3VZdUaWrKKIRa8WitBoBjr0I1M04ZDXalUqpLBFyMKThbadxIYMCONIebPlJ4zkZ4ifnWE5Vnjo46 h4c796T5+A1kEHaq0Sbl290w4VDTDL4RE2kZTUFVz14gHzF7UsOMgwhhfSLm4nFL8pngVffJYcPcd McjaBZfCxKcPvCcfL1c8/6I10O3/uR9N/q9hP640n84I1KW4GLgSS/pkBIU3UNGXEBLwUqQhzV5xR zKdVvzhkLUkEoKYE01eA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nW0b3-005jMv-4W; Sun, 20 Mar 2022 18:48:09 +0000 Received: from mail-qk1-f180.google.com ([209.85.222.180]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nW0ay-005jMM-Ro for linux-arm-kernel@lists.infradead.org; Sun, 20 Mar 2022 18:48:06 +0000 Received: by mail-qk1-f180.google.com with SMTP id v15so10369612qkg.8 for ; Sun, 20 Mar 2022 11:48:04 -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=zNUU20JYr/XCYRrX4tGKAZ+3B2SaozQZu855ahnTeKE=; b=Pbk7eomBm372gkVQ9K7qV03PrSrSQWwGu1Iqdw2h8+4cwrIUEgCf5t8U+Nt1D3VI90 FEPkWOVLSDoD6k8FBQrixSTrpmAU9dGPMCBwC3KCEU70K8ZfMiTsRVocRBGcMDC4cVjl 8wLHc1NDvhcbdEtScNh3uk12yrignUMcraAOnv53cOLLxrnTBjoL8dbYuDtBJ8La7glN c0Qz8kreArPqUst8GFWPtXxfFMWGJQC5MbSbFr3OkTK2Bum1D1nnj9ysZQ9xN6gsIVEB JWYCNd5uWrVO+9azn+9lwjPpvjRLnak0fpHGk+TtLYjGL/J5wrzu3MQjBr5GC4bVd6nm YbIg== X-Gm-Message-State: AOAM532GsxQyrenqApNH7UjWNigXqyDInj9K1pCcok7ZtZmZbSt8QTBn P62d1hBFj1zLs4C+6OBCXPCZ5uciRg== X-Google-Smtp-Source: ABdhPJyhERCoe29vpwn80+Bn0p6qmL/P6VevxfzOyv+qt6vppZBPu8RpmQgniVLAwbjJLDfybonECQ== X-Received: by 2002:a05:620a:25cb:b0:67e:9ae8:1563 with SMTP id y11-20020a05620a25cb00b0067e9ae81563mr1128808qko.222.1647802084011; Sun, 20 Mar 2022 11:48:04 -0700 (PDT) Received: from robh.at.kernel.org ([2607:fb90:c6d:21ec:c4f5:bb3:5269:3b0e]) by smtp.gmail.com with ESMTPSA id s31-20020a05622a1a9f00b002e1df010316sm10605821qtc.80.2022.03.20.11.47.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 20 Mar 2022 11:48:02 -0700 (PDT) Received: (nullmailer pid 3198157 invoked by uid 1000); Sun, 20 Mar 2022 18:47:56 -0000 Date: Sun, 20 Mar 2022 14:47:56 -0400 From: Rob Herring To: Kuldeep Singh Cc: Robin Murphy , Marc Zyngier , Daniel Lezcano , Thomas Gleixner , Marc Zyngier , Mark Rutland , linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v2 2/3] dt-bindings: timer: Document arm, cortex-a7-timer in arch timer Message-ID: References: <20220317191527.96237-1-singh.kuldeep87k@gmail.com> <20220317191527.96237-3-singh.kuldeep87k@gmail.com> <558f0c92-c499-daca-e1ad-2b16137f8c06@arm.com> <20220317212508.GB99538@9a2d8922b8f1> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20220317212508.GB99538@9a2d8922b8f1> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220320_114804_949185_58CC0469 X-CRM114-Status: GOOD ( 29.33 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Mar 18, 2022 at 02:55:08AM +0530, Kuldeep Singh wrote: > On Thu, Mar 17, 2022 at 08:25:12PM +0000, Robin Murphy wrote: > > On 2022-03-17 19:15, Kuldeep Singh wrote: > > > Renesas RZ/N1D platform uses compatible "arm,cortex-a7-timer" in > > > conjugation with "arm,armv7-timer". Since, initial entry is not > > > documented, it start raising dtbs_check warnings. > > > > > > ['arm,cortex-a7-timer', 'arm,armv7-timer'] is too long > > > 'arm,cortex-a7-timer' is not one of ['arm,armv7-timer', 'arm,armv8-timer'] > > > 'arm,cortex-a7-timer' is not one of ['arm,cortex-a15-timer'] > > > > > > Document this compatible to address it. The motivation to add this > > > change is taken from an already existing entry "arm,cortex-a15-timer". > > > Please note, this will not hurt any arch timer users. > > > > Eh, if it's never been documented or supported, I say just get rid of it. > > The arch timer interface is by definition part of a CPU, and we can tell > > what the CPU is by reading its ID registers. Indeed that's how the driver > > handles the non-zero number of CPU-specific errata that already exist - we > > don't need compatibles for that. > > > > In some ways it might have been nice to have *SoC-specific* compatibles > > given the difficulty some integrators seem to have had in wiring up a stable > > count *to* the interface, but it's not like they could be magically added to > > already-deployed DTs after a bug is discovered, and nor could we have > > mandated them from day 1 just in case and subsequently maintained a binding > > that is just an ever-growing list of every SoC. Oh well. > > Robin, A similar discussion was already done on v1 thread. Please see > below for details: > https://lore.kernel.org/linux-devicetree/20220317065925.GA9158@9a2d8922b8f1/ > https://lore.kernel.org/linux-devicetree/726bde76-d792-febf-d364-6eedeb748c3b@canonical.com/ > > And final outcome of discussion turns out to add this compatible string. I agree with Robin on dropping. More specific here is not useful. If we're going to add some cores, then we should add every core implementation. If one has a big.LITTLE system with A15/A7 what would be the right compatible value? > > I see people with different set of perspective in regard to whether keep > compatible string or not. We should have some sort of evidences to > support claims so that next time when similar situation arises, we'll be > aware beforehand how to proceed. Every situation tends to be different. Rob _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel