From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 733491A6827; Wed, 13 May 2026 02:55:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778640939; cv=none; b=oaR60s/R1q8z6iNXreOuureep0qnx/3UV54HeSk4GqiQJK7ymC3gfq2CQBaNzbgrMc8dVW2UTSzmKKRpyUUPjmJuu9pYrI4ccRMZabtYr2nA9diwS9k7rMQ5STwQZF0ytHsZqKYBgW1u+AZjsqmtBbMtGY09MsYp10Ze2jfDQcI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778640939; c=relaxed/simple; bh=KY5EBXwZQG5saMPKhdqgNw/ld46j/zdvuqz7wPdRRAY=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=KJL++7HEMfIoMuw93/C2BDkJqnwPdk4rbm8KDox5tRZbI29bXuWiUXIpkv8mSir0AqBZt61zfw5nm5i0Tg5XjNlS+js4tVOeURaNC2nKPDsESBfLGfU/4AL8BpSJ61hHd6QlArEkHQshQMBVKSTYtPYncXlNEYa2mkd4g8P5nI4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Pe8SRaGF; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Pe8SRaGF" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CDB93C2BCB0; Wed, 13 May 2026 02:55:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1778640939; bh=KY5EBXwZQG5saMPKhdqgNw/ld46j/zdvuqz7wPdRRAY=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date:From; b=Pe8SRaGFkkY3bTqZg0/aGWBG6m/SxIT2xm8EezxGWnpj3xB3YgjAR7fU8q2VM+HsR qT9idlO6QhMsLlL9o0ejjchkB/zivk/FP/0C/Oxj3bh/IPjUvcVwg7LInCXsRkqwcY A24aHixXvhTIab09MvY8sagcBITkFgsSev26grrc7We+hE6gd/XUdAzp2TREu6Fx8n ssPMlPiMgZboL0hyWysyPQF+s90QOvmGgd0A+yhE1ZqCNcKsFAH2HvIIJc/wW07HqE Qvlosib4h9z3ZisBOiMrAGgBjf8d1vItM8dARSTD5x/dYi9hLVwPfAXM1W/x1w2x27 s2yIF6VrAIshA== From: sashiko-bot@kernel.org Subject: Re: [RFC PATCH 8/9] arm64: dts: renesas: r9a09g077: Use SYS syscon for WDTDCR access Reply-To: sashiko-reviews@lists.linux.dev To: Prabhakar Cc: wsa+renesas@sang-engineering.com, linux-watchdog@vger.kernel.org, krzk+dt@kernel.org, devicetree@vger.kernel.org, conor+dt@kernel.org, robh@kernel.org In-Reply-To: <20260511185058.1926869-9-prabhakar.mahadev-lad.rj@bp.renesas.com> References: <20260511185058.1926869-9-prabhakar.mahadev-lad.rj@bp.renesas.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Wed, 13 May 2026 02:55:38 +0000 Message-Id: <20260513025538.CDB93C2BCB0@smtp.kernel.org> Precedence: bulk X-Mailing-List: linux-watchdog@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Thank you for your contribution! Sashiko AI review found 1 potential issue(= s) to consider: - [Medium] Removing the second `reg` entry breaks backward compatibility wi= th older kernels. -- commit 4d641e4436b59e57d0434635cc0bb0ee418c05e5 Author: Lad Prabhakar arm64: dts: renesas: r9a09g077: Use SYS syscon for WDTDCR access This commit updates the r9a09g077 device tree to use the SYS syscon for WDTDCR access. It removes the second reg entry from the watchdog nodes and adds a new renesas,sys phandle property. > diff --git a/arch/arm64/boot/dts/renesas/r9a09g077.dtsi b/arch/arm64/boot= /dts/renesas/r9a09g077.dtsi > index 59e5de7438261..b076bea9cb709 100644 > --- a/arch/arm64/boot/dts/renesas/r9a09g077.dtsi > +++ b/arch/arm64/boot/dts/renesas/r9a09g077.dtsi > @@ -327,61 +327,61 @@ channel1 { > =20 > wdt0: watchdog@80082000 { > compatible =3D "renesas,r9a09g077-wdt"; > - reg =3D <0 0x80082000 0 0x400>, > - <0 0x81295100 0 0x04>; > + reg =3D <0 0x80082000 0 0x400>; Does removing the second reg entry cause a backward compatibility regression with older kernels? Device tree is considered a stable ABI, and older kernels lacking the new syscon driver support might attempt to parse the second reg entry for the WDTDCR register region. Because the second entry is removed, devm_platform_ioremap_resource(pdev, 1) would return an error, causing the watchdog driver to fail to probe. Could the second reg entry be retained, or a new compatible string introduced, to preserve DT ABI stability? [ ... ] --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20260511185058.1926= 869-1-prabhakar.mahadev-lad.rj@bp.renesas.com?part=3D8