From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from PA4PR04CU001.outbound.protection.outlook.com (mail-francecentralazon11013045.outbound.protection.outlook.com [40.107.162.45]) (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 9B38947ECDC; Wed, 13 May 2026 15:05:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=40.107.162.45 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778684735; cv=fail; b=qio1mOzcSOc/AXsyzcXoCH0Nna3Qrsh+AXmVH8H7xy0Y/4MWAh4Zs+j3eykV+buiXw3Ec1r/DoNy1VgscPyQKYYNtJ0HasGEoF1298qs9+ifDuYIsLIVhtnS4p2xP+tQKUAEbLjjymDC8adLQSk+HhK4/tYwnUAowVnbrwzGvDQ= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778684735; c=relaxed/simple; bh=TgBZcLif0hhXGXA1V22Ef4vKv+xedKR3nr1NN9aHvko=; h=Date:From:To:Cc:Subject:Message-ID:References:Content-Type: Content-Disposition:In-Reply-To:MIME-Version; b=N34uF7kLV35fWUoe4DV3sAJjEHfrqYy8+QBvPVkl10SwQ/7yEZhqHnrhuRv6rzeV1C2ax5zhWkXy0+ZOfQHvAg6NDzmv/ZrfRc3Ti2+XFQDDIODGJhG7xfq7GzvD55rCQrjiZc8XcCoA8r7pAPQhTI+9txQXh4ovfsaXJT+SXug= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=nxp.com; spf=pass smtp.mailfrom=nxp.com; dkim=pass (2048-bit key) header.d=nxp.com header.i=@nxp.com header.b=WgoP9C6V; arc=fail smtp.client-ip=40.107.162.45 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=nxp.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=nxp.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=nxp.com header.i=@nxp.com header.b="WgoP9C6V" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=Lf+QBQBQtW1KG9scmjAr5pdqLkldsp523GTjY/hO6raOs3cz+nRe01oWnpZkYdhUJROrCxa86yQuS67ioGagOk6xmU0lzMtyOlWhl6G2MxSpfDqOaJXSDIJpcJGLtIxJSDqYbqxM19zCDHaPxhzd77lJphL84PMQqTncNlGVikSn+CK5I2ZB3HztjmVNKnerM5cFpNUFGXzl5vqclQ4R7rsTxhzXo6kymOkgkh2RXpP4Ro4VuGJpe2r+dV7ARD2GDZM3VE5vKBfYlRuW9fDTqgcBj7jeQ+q+Gynv5fwGKM0B93fDqFHeReBsQSXrZbJWms6VZubEyx37f8AXkharKg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=eXwBuTNKac/ijeDOICYQdqGAdzGhH9wx8RjX4MOyYGQ=; b=pCD59kBP37VGOj1wJ/THxPhwOiIWrYfweWGBmN31vZJkBdVof3FhpFMoDff3BHkkUeM+vsQr98HNh1p7dLIJUS8bJRLZYnd08AbEM3zcmpw7i++viefzjlHmDf5L1dGG3aa2fIhgB7xW78Vx+oo6i53GHvqJAoAR6UX9zA1t5NbLYizcbpYSOv5RYCD3eY8NaZMEv6d+dmROKIAClRrgUUo+ZzQxLyay404rvWc/PQiQjqqDq1PkcVa3/1xeoCKTEm5RfIzjIG8UIal+Ia35KXDz40sm8pLZA+AUkXtp2TUKLmVzAgWTjKSzfO3HR574gxcGE0eIlF05SqA842O88w== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nxp.com; dmarc=pass action=none header.from=nxp.com; dkim=pass header.d=nxp.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nxp.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=eXwBuTNKac/ijeDOICYQdqGAdzGhH9wx8RjX4MOyYGQ=; b=WgoP9C6VUEzLHbY1vRf059Abthd47D/YLgaYgJgapkDC73AS0bWh9xMpj/YPw5Ytrj9LcnB0b8xVEmRl0IUfqopaVtpuZ532L50fEkkT16nZjBdfZfZ00mLxe67HK5LyjSQKgFt1tEco81Ou78g6KW6vMbx94/rcS/xiWfcs/bI9dOKXM5asQ+iZDNEccjm19nm8xLZxhhUMPRcLTOW5uPc1Awck39jw/gWEQ80gT0T5bmpVBM8E9AVG0NtiD0XCupZ08Xxul++7951hE7QcCiRR2BJSkiLIfGTd+ZC7sgvmCPWJRrBf29VXTU6alKJKZnqpU9iFcbBs9iNR6B3TrQ== Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nxp.com; Received: from PA4PR04MB9366.eurprd04.prod.outlook.com (2603:10a6:102:2a9::8) by GVXPR04MB10248.eurprd04.prod.outlook.com (2603:10a6:150:1c1::10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9913.11; Wed, 13 May 2026 15:05:30 +0000 Received: from PA4PR04MB9366.eurprd04.prod.outlook.com ([fe80::75e4:8143:ddbc:6588]) by PA4PR04MB9366.eurprd04.prod.outlook.com ([fe80::75e4:8143:ddbc:6588%3]) with mapi id 15.20.9913.009; Wed, 13 May 2026 15:05:30 +0000 Date: Wed, 13 May 2026 11:05:22 -0400 From: Frank Li To: "Miquel Raynal (Schneider Electric)" Cc: Michael Turquette , Stephen Boyd , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Thomas Gleixner , Olivia Mackall , Herbert Xu , Jayesh Choudhary , "David S. Miller" , Christian Marangi , Antoine Tenart , Geert Uytterhoeven , Magnus Damm , Thomas Petazzoni , Pascal EBERHARD , Wolfram Sang , linux-clk@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Herve Codina Subject: Re: [PATCH 10/16] clk: Add support for clock nexus dt bindings Message-ID: References: <20260327-schneider-v7-0-rc1-crypto-v1-0-5e6ff7853994@bootlin.com> <20260327-schneider-v7-0-rc1-crypto-v1-10-5e6ff7853994@bootlin.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260327-schneider-v7-0-rc1-crypto-v1-10-5e6ff7853994@bootlin.com> X-ClientProxiedBy: SA1P222CA0117.NAMP222.PROD.OUTLOOK.COM (2603:10b6:806:3c5::23) To PA4PR04MB9366.eurprd04.prod.outlook.com (2603:10a6:102:2a9::8) Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: PA4PR04MB9366:EE_|GVXPR04MB10248:EE_ X-MS-Office365-Filtering-Correlation-Id: 3b45347c-ae25-4949-86fa-08deb10112ac X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|7416014|376014|52116014|1800799024|19092799006|18002099003|22082099003|38350700014|11063799003|56012099003; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:PA4PR04MB9366.eurprd04.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(366016)(7416014)(376014)(52116014)(1800799024)(19092799006)(18002099003)(22082099003)(38350700014)(11063799003)(56012099003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?yvuRAJtIUwzpJa249E2pbYsXWhLtreoSbTCXIJV+j40xy90Wua0GDafvpDsO?= =?us-ascii?Q?RxvwHYXL9Z6dGCrf4DNNCqpbZYUxubkbgrwOyMxzb7p0oMCA0i3IpuCNTOM2?= =?us-ascii?Q?/AoNxGQyFrx3WmhOVmirP9yhXO21HURKKPRjkai25IZK54XJwlBjW3V6jieD?= =?us-ascii?Q?K8BG6kdnDdg9FoPKRwKHEhjslBeivsa7HjPRFcvSNduby8RYQg4mdQ5V/7UP?= =?us-ascii?Q?+RU4NXDEKIIQf7XFQiCtFbI4DVRWCldvTZ5oUyti9qds0kM6y6yQg1+x6UAR?= =?us-ascii?Q?K3TMvrYI8E0HaxthESQV8r4z7tWwvOa0fLaCSjOIzhQV1chnia1fEDtd0m/L?= =?us-ascii?Q?B6iqMhGIxf0mjUUD7khZiny4wN7nT7uIuGtBGPSO/e1V6ejt4E2nuW+7R7tj?= =?us-ascii?Q?6Mc8IfjHzE3CWV9vWQaD15r+GUccA3qOJMcFLy1DQv+a5KWrB9pUOurZdZ3x?= =?us-ascii?Q?fqy7GvWVf+TsqF8R4zXVLI/2r1CTLeoI2O8ZLdu84RnplICETnDLVGtKEhDF?= =?us-ascii?Q?maIz9Uc/VQ7/3V27i9cIFXVYlGG/QjNkhvKQzpJ0oFYT27btGSHIChuNFoQW?= =?us-ascii?Q?ao1x1GPADfF5Y+qE0tQyUuEvCDwWzlMosKGFXAmTgtQMjs1eWzc5jLqYKeEF?= =?us-ascii?Q?9cC8+FtPh2H9UbO1dbCYC/Ysq6IOZRmxM5TQJJ97nNmVHdiM+Dax67SRs3UR?= =?us-ascii?Q?avsGVxKJAcrDonviRKIY6bQzIZTDGa1wf0m7tX5YaJSB+HbGZTsJ2I8Eoq09?= =?us-ascii?Q?fRwtDUHJKQGrsuydEX/0AIIR4gf3LmZUFdsEMuNx/EEQgqifu36MjfjbAK9W?= =?us-ascii?Q?3DfDgQU/bQebA1bY/ui1eXLhBg6hdqHmOjYFfww7pYPbzuGRiYAcKYhIZ6eJ?= =?us-ascii?Q?KjeNzSound/PBYXc6YMUlWcgeBFiE9TJ2v7jrAHc0XKmdcPR0bH5y7mXf4jz?= =?us-ascii?Q?YIxhJuei7Z1ulryXcgnJD1FEYabDD2Od/LQyJ3hLEbIFSnCr3iqTVc1VKRKJ?= =?us-ascii?Q?Y4Ca9zB0RI5H9QZWpDiaJGfpBZcAnBw+zC6cHQbHXNy9WCIkC880KfJ3GnB6?= =?us-ascii?Q?ItefvbpE69qybbHYreXAOe859n64eEvicyVaQmkuJAZJmfQyKjHpJ/3d1lSt?= =?us-ascii?Q?f1FnHpinF9tiivKPthOCab/dfYNdG06ZDY8+Qix+CdTjU1RQWYde+EwJx3WL?= =?us-ascii?Q?o3LNhs606bNe9j7RzwGRbb/VSZvTzwb/HSpPIgMmNJ1XvnAwNwkVinNrnQVf?= =?us-ascii?Q?AaRPpBN+rJNpFYXTi4CbbLZT3ABir9eofwtfCzqsHOWGI0+noUSW1bnUDK+U?= =?us-ascii?Q?dd1PNzM7gY4ZE0nzqEX6bPWK/0DCSlLtxFKjyWVwQQX4nfD8SIL/lUDy9dP0?= =?us-ascii?Q?a5ZRJzJMyUh1wGfivVSPoJzIpPxR768t1BQaKoyb/LOutmPgZiH5kk9Uyhsg?= =?us-ascii?Q?5c2uPL05drcaTDCcydC1+YyBjyEcOUG2eYfl4TS4g+F/0Ix1/Q9jlTZamUln?= =?us-ascii?Q?nVHEcb+nFv2vMtlYBeAwFXQnCMTgKTjOs2+O0Ng+UIj9T0E3uq9Csm7w77qc?= =?us-ascii?Q?uUKqxwvqHgss8W/G8qqp4Thcc8RgScvD0C/AUgsALTUxE2VqXncO8Od7GKWU?= =?us-ascii?Q?g9QIrKL77WLaZvGifqcq1eUUTXuOtIUIJ9p3BcsdlzjlFSH3BhEnnPNOP1ox?= =?us-ascii?Q?FfylcJwBOpXh2Pu4EW/fEbZrwWyFRTxleyZslaoekZ76IEqk?= X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: 3b45347c-ae25-4949-86fa-08deb10112ac X-MS-Exchange-CrossTenant-AuthSource: PA4PR04MB9366.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 May 2026 15:05:30.0935 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 686ea1d3-bc2b-4c6f-a92c-d99c5c301635 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: DbQVt2HC6fzM9iZDy4GSBVWnX2sEMdgwL+e2mw9aRkLqh8VyPq0RcKLlQHr0eAU9MF/Lr7w9ZHwsLESLcnIThg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: GVXPR04MB10248 On Fri, Mar 27, 2026 at 09:09:32PM +0100, Miquel Raynal (Schneider Electric) wrote: > A nexus node is some kind of parent device abstracting the outer > connections. They are particularly useful for describing connectors-like > interfaces but not only. Certain IP blocks will typically include inner > blocks and distribute resources to them. > > In the case of clocks, there is already the concept of clock controller, > but this usually indicates some kind of control over the said clock, > ie. gate or rate control. When there is none of this, an existing > approach is to reference the upper clock, which is wrong from a hardware > point of view. > > Nexus nodes are already part of the device-tree specification and clocks > are already mentioned: > https://github.com/devicetree-org/devicetree-specification/blob/v0.4/source/chapter2-devicetree-basics.rst#nexus-nodes-and-specifier-mapping > > Following the introductions of nexus nodes support for interrupts, gpios > and pwms, here is the same logic applied again to the clk subsystem, > just by transitioning from of_parse_phandle_with_args() to > of_parse_phandle_with_args_map(): > > * Nexus OF support: > commit bd6f2fd5a1d5 ("of: Support parsing phandle argument lists through a nexus node") > * GPIO adoption: > commit c11e6f0f04db ("gpio: Support gpio nexus dt bindings") > * PWM adoption: > commit e71e46a6f19c ("pwm: Add support for pwm nexus dt bindings") > > Expected Nexus properties supported: > - clock-map: maps inner clocks to inlet clocks, > - clock-map-mask: specifier cell(s) which will be remapped, > - clock-map-pass-thru: specifier cell(s) not used for remapping, > forwarded as-is. > > In my own usage I had to deal with controllers where clock-map-mask and > clock-map-pass-thru were not relevant, but here is a made up example > showing how all these properties could go together: > > Example: > soc_clk: clock-controller { > #clock-cells = <2>; > }; > > container: container { > #clock-cells = <2>; > clock-map = <0 0 &soc_clk 2 0>, > <1 0 &soc_clk 6 0>; > clock-map-mask = <0xffffffff 0x0>; > clock-map-pass-thru = <0x0 0xffffffff>; > > child-device { > clocks = <&container 1 0>; > /* This is equivalent to <&soc_clk 6 0> */ > }; > }; > > The child device does not need to know about the outer implementation, > and only knows about what the nexus provides. The nexus acts as a > pass-through, with no extra control. > > Signed-off-by: Miquel Raynal (Schneider Electric) > Reviewed-by: Herve Codina > --- Thanks. Reviewed-by: Frank Li > drivers/clk/clk.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c > index 93e33ff30f3a..196ba727e84b 100644 > --- a/drivers/clk/clk.c > +++ b/drivers/clk/clk.c > @@ -5218,8 +5218,8 @@ static int of_parse_clkspec(const struct device_node *np, int index, > */ > if (name) > index = of_property_match_string(np, "clock-names", name); > - ret = of_parse_phandle_with_args(np, "clocks", "#clock-cells", > - index, out_args); > + ret = of_parse_phandle_with_args_map(np, "clocks", "clock", > + index, out_args); > if (!ret) > break; > if (name && index >= 0) > > -- > 2.51.1 >