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 X-Spam-Level: X-Spam-Status: No, score=-5.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MSGID_FROM_MTA_HEADER,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F0884C63793 for ; Thu, 22 Jul 2021 09:46:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DB9AD61029 for ; Thu, 22 Jul 2021 09:46:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231463AbhGVJFf (ORCPT ); Thu, 22 Jul 2021 05:05:35 -0400 Received: from mail-eopbgr00083.outbound.protection.outlook.com ([40.107.0.83]:3904 "EHLO EUR02-AM5-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S231417AbhGVJFa (ORCPT ); Thu, 22 Jul 2021 05:05:30 -0400 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=iM8l22t5cc9VS4WyH2PpS71Fga1x7OzshaXoXIGS8RJQyqwie7hTF4QxzPwrCn0sd2R+A5cmfALy9zCcQ2ZO04k4bijBSPeKmzTp4i+NjeczUw/ongP7uVVOnq68UoATG+wdCPFgnnfn8EkQI/DgL61Sla4ZBHuBwwJXJxbv6HwOzKVmV1FKW6JaWWxM9iJX33ShyxuU7D6LsoKtv0C1ZfmZ+05lGjZ16IOYS5ZiiAS1/rah9GHckucTLnygnABMU76ZmvxW4IJ1fp5C1Cw8hpjPDxQN8XCM3yZVA9A5H1Lrcf30jEEGE1LN+Xl2ctA81e5QEeddWlzZxRnt6/dknw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=GI63k0pfcgubGsH7+yvOVpNphLc/V+RuMjPgnlDlV04=; b=U7EiEn1IbQzZGbKqEb1lTr80ixj0gRCnAqTKwsUTrCpfG20yTSm+kpWsn60YAqEq6u3od5wGRz+YyKoBQQYpV9je6noJyPbciBryvlbavgf14sEXGKyUHcZFFCBE/gcb8BJ13LM6zKU7l34rs/DYIGUItcqrDajC3PO7HLAbsCbqUkq82HMetePb+rP1TUS/HK8RTh9Ip+eg3emIBatFSOoGjOh/gh7IUctbpF+Kq5PZaz5Nkw6nypTLwdtEn/OEY9EBAH/HgTpL9ky1/D1LhqftvvLypySbA2REEFwf1Tj5sFvpkU9NZk6BvBVv7ub208Nki8QxYhzmcEVDb2O4Ig== 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=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=GI63k0pfcgubGsH7+yvOVpNphLc/V+RuMjPgnlDlV04=; b=d14cgVtTbGPoRPnU1Zp+7y7jdD67QBGUHcTKW2Ijpg7Tv6KTg2Dej2Vg7Bt3IAngIhAfJXG74I4Y3pn5MEzJrNTaCewwSPEunvuH2PqWwyHabCLupdxDfee6DSVJVoeBbLkZH5SPIdFtDQAW376LGGinhyc+OwxF+dNL9sT8s0Y= Authentication-Results: gmail.com; dkim=none (message not signed) header.d=none;gmail.com; dmarc=none action=none header.from=nxp.com; Received: from AM7PR04MB7046.eurprd04.prod.outlook.com (2603:10a6:20b:113::22) by AM6PR04MB5208.eurprd04.prod.outlook.com (2603:10a6:20b:9::32) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4331.28; Thu, 22 Jul 2021 09:46:03 +0000 Received: from AM7PR04MB7046.eurprd04.prod.outlook.com ([fe80::8c66:a7b4:1dc7:2c27]) by AM7PR04MB7046.eurprd04.prod.outlook.com ([fe80::8c66:a7b4:1dc7:2c27%8]) with mapi id 15.20.4352.025; Thu, 22 Jul 2021 09:46:03 +0000 Message-ID: <08ca856c013aba60e686f050e06a6e3179de6030.camel@nxp.com> Subject: Re: [PATCH v2 2/3] clk: fractional-divider: Introduce NO_PRESCALER flag From: Liu Ying To: Andy Shevchenko Cc: Andy Shevchenko , Heiko Stuebner , Elaine Zhang , Stephen Boyd , linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, Michael Turquette , NXP Linux Team , Jacky Bai Date: Thu, 22 Jul 2021 17:43:49 +0800 In-Reply-To: References: <20210716133448.24890-1-andriy.shevchenko@linux.intel.com> <20210716133448.24890-2-andriy.shevchenko@linux.intel.com> <9117e5212a3b743ca541918ec2b701c159ac752c.camel@nxp.com> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.36.4-0ubuntu1 Content-Transfer-Encoding: 7bit X-ClientProxiedBy: SGBP274CA0002.SGPP274.PROD.OUTLOOK.COM (2603:1096:4:b0::14) To AM7PR04MB7046.eurprd04.prod.outlook.com (2603:10a6:20b:113::22) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from blueberry (119.31.174.66) by SGBP274CA0002.SGPP274.PROD.OUTLOOK.COM (2603:1096:4:b0::14) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4352.24 via Frontend Transport; Thu, 22 Jul 2021 09:46:00 +0000 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: a0864181-748f-4a9a-8027-08d94cf5851f X-MS-TrafficTypeDiagnostic: AM6PR04MB5208: X-MS-Exchange-Transport-Forked: True X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:10000; X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; 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:AM7PR04MB7046.eurprd04.prod.outlook.com;PTR:;CAT:NONE;SFS:(4636009)(366004)(6496006)(6916009)(7416002)(2906002)(52116002)(53546011)(5660300002)(186003)(956004)(4326008)(316002)(83380400001)(86362001)(2616005)(6666004)(8676002)(66476007)(26005)(508600001)(66556008)(36756003)(38100700002)(6486002)(38350700002)(8936002)(66946007)(54906003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?cFNvclpnZDRxWDkrOVJzekVxeElvd2xDTTBXc3ovWGpiZ1VVcWNRNG1FN3hz?= =?utf-8?B?YzJjWUVPQkRCcUViV1FsM2tDZm5KWWxMMElSUWhVOEs5Zm9sN2tBYkxhNjhm?= =?utf-8?B?SGFUaFU0S0RSMmg2QXFUNUl6VmdWZkFWTXNSaDdWTXRva2YvazhnRmZHTzlw?= =?utf-8?B?emF5TDVwdUlNMnJFTUdTQUpxRW1EWDg1b3lxVlNrRkovOWFxV1Y2b3RZN0tW?= =?utf-8?B?Y3VyS1lyOWhjbnkwc2VSM3YrMG1JSDIvdzloSHZoK21lb3NnTkF2Qzl4ZVFC?= =?utf-8?B?UkVSU0hvMkgyRnlxUzJ2YzFWa0ljZFZ0OUdERURwUXljVHpoOUZiaUZlVTNP?= =?utf-8?B?MHpseE5weFc4TjVPNzZPRlBqNXVaMzlzVWJIM1JqU1NPTEF5eVozVWNNWmY3?= =?utf-8?B?ZW8yYUhhOUlDU1JzRlppeG1sNHFYeGtlN0ZBcVdKMmh1TStyL3ZCQ0cwU3kr?= =?utf-8?B?VU1COHZCSmdZS3dYN3cyK01mdnR2cXBUVzFBcEx4dFYvbG9SQ2Y1ckRXREEx?= =?utf-8?B?Q0wwN1Zlb0hNRmVZdkF2aFMxemdza0JhOE54NXFMdmlXZlgyVEJvTWtpYzZJ?= =?utf-8?B?Ty84Qm1NLzE3S1BvYklRdFJQR1ZQcExydEFsNGpVTFJnWCtEV2RzRmJoQzd5?= =?utf-8?B?YThxcU42SWYyYXh4cGxIdDBlRjZ0UURwaDQ1N0R6WDRwcXBwSW5va3JobWpj?= =?utf-8?B?RGJuT2lOVDlyVnlXelFwNTh6T2xFRUZ1V2p4eXc3Ynp1ZjBzemJ6bi8zZzMw?= =?utf-8?B?Y3JoakVRQnFHaE50a0c5YmNNVlhzSzUvWHNWRm5vdWhhaDNHZkhiN092QkZB?= =?utf-8?B?UDNXblBkdmJoaS9lZ01GMWJNUTlLU256Y21Ib3BlRjBJMHh4Ny9makNiMXM5?= =?utf-8?B?S21EaC9qYUY5UmhXb0czUDArdVpYWENHT2FoaUtrYURwazBFVXNrT2RKRzdj?= =?utf-8?B?OHVzZlNJVldsRFFEdzlrSmlZY1FFY3dBL3JjMXhxNld1SktQR0lxUWxVVDZr?= =?utf-8?B?TFRzdHhiQzgvQTZsUmtVUW1HblZKN3c5ZkRKdlV0Tlh3T2VsaTZTVjB6d0Fx?= =?utf-8?B?bmoxWWRWcGFDRGpvQ2pRYjk2dGZYaG8zanpvaVhhV05uOHVMTGhEbldHSit3?= =?utf-8?B?NkZOT1J3QnRXSHpDV0tCMjVlS2EzdFgxZmtORjlQemowOFZZZ0VUeVJTdCs0?= =?utf-8?B?U3Y1S2RnVTZhbUxYdnBPNmhKRTVOTFovcWpwelQrOG0vb0pCZDZNUlNkNGxj?= =?utf-8?B?SHNJcFM3MWR4U0pRWXNOc2ZNTkdjOGp6MkRhM1ZuOEdwTHVWM2VxVUdhNmZi?= =?utf-8?B?cVRpVFVnRkpyT25NOVE0S05OKysxUm8vMVJtRWFqb2VKQU9BWHBUQ29WMlhW?= =?utf-8?B?VnNkV3RlT3ArMC81WnFSVm8xWmNrNDFISFhYcnhLbzhrZmd4cjJBM203bVhR?= =?utf-8?B?b3BGZ3Y2WmY2bjNZNWdFcnhMamp4SXVqRCtYcVZCZER0aVREWnBaMTdQSjlw?= =?utf-8?B?SmszS2JwbXJMZDNJV2hQRHFNc0FISXlRQzdFcVZZUUtYU2hvUU14V2trV0J2?= =?utf-8?B?UTlJaWVNMjdDcko1S2QzQldMZFZkV0dMMWFqbng1QXNBSndtR3NGY0ttbUVH?= =?utf-8?B?dGdQWDJXT1diaTQyNWNZR3JNR3RKOU5lQzl6U2lOY0ppcFF1UVZBRmk0eVJa?= =?utf-8?B?TlliQXpTczlsYTNxYnQ5b1VOMFRZVGo0N0NmT1ZUTTQ4NTdpaDBGWVJRUFV5?= =?utf-8?Q?qjgGgExxGIuv4cXP3rIbPsh7NubrFg37ewNzpLU?= X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: a0864181-748f-4a9a-8027-08d94cf5851f X-MS-Exchange-CrossTenant-AuthSource: AM7PR04MB7046.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Jul 2021 09:46:03.4754 (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: 3DkEGy3XH0Rps/tsCSbdhOrjLjdCx1QshJPxYD2MvisfswKgx5m6RRoYTzUBOBP66sf3dmg5jf3YUargkJjvug== X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM6PR04MB5208 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2021-07-22 at 12:38 +0300, Andy Shevchenko wrote: > On Thu, Jul 22, 2021 at 12:33 PM Liu Ying wrote: > > On Fri, 2021-07-16 at 16:34 +0300, Andy Shevchenko wrote: > > > The newly introduced flag, when set, makes the flow to skip > > > the assumption that the caller will use an additional 2^scale > > > prescaler to get the desired clock rate. > > > > As I mentioned in v1 comment, it seems to be good to decouple the > > prescaler knowledge from this common fractional divider clk driver. > > This way, we'll make it simpler and easier to maintain. Also, then, the > > NO_PRESCALER flag is not needed at all. However, it seems that two > > Intel drivers which use the frational divider drivers will be affected > > and rate negotiation logics need to be implemented for them. Please > > consider if it's doable or not. > > The current driver works for the certain hardware without this change. > If you think it's better, submit a proposal we will discuss. Well, I'm not afford to do so. Just share an idea. I haven't got the intel HW to test. As I mentioned in v1 comment, it seems that you have experience on relevent drivers and HW to test, may I encourage you to do that :-) Or forget that if you really think you won't do that. > > > If we ultimately keep the prescaler knowledge here, please consider to > > add the NO_PRESCALER flag for i.MX7ulp as it hasn't the prescaler IIUC. > > You mean there is a code which is currently using this driver w/o > taking into account this prescaller flavour? Can you, please, point > out, I'll definitely update it. Thanks for the catch! drivers/clk/imx/clk-composite-7ulp.c Regards, Liu Ying > 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 X-Spam-Level: X-Spam-Status: No, score=-5.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MSGID_FROM_MTA_HEADER,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 75E39C63793 for ; Thu, 22 Jul 2021 09:47:37 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 4478361244 for ; Thu, 22 Jul 2021 09:47:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4478361244 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=nxp.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-rockchip-bounces+linux-rockchip=archiver.kernel.org@lists.infradead.org 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:MIME-Version:References:In-Reply-To: Date:Cc:To:From:Subject:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=W0dBNiBpsJsxU89ano5604E0HpVNUngtc6cg1DjMGtw=; b=iGB8xk8Hi8o7bR KYoi9VLmPkdZXCrLoW800EHgboTDgaGUPkDvbxEWnZcrbeZTyY++xtwABAXuGaKAC9OBhCYtLoOUA 76GHbAFVPMaEbJvriJVYrf4w6iAsB3dy8eULvWg7aCWRgEb/XDAYitzJmr1HUF2fv5fCVZrROzEou 6FGPaFkUNh75GJzjlAjM0zb3CTZXa4BzymN8RMbf1dUXvW5k+cSYzGeiimFx4wMroQ0KrOFyQmY/M uAt6nEq8e+0Vw35NVBoTwMOPtkewBHyy/XEc0SUZ/KujQ7ce5CaRi5mrh+dx6g/AXG6/7iOOELovx 62ZvW5jY8r/oiLpOGfow==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1m6VIh-000zUJ-Si; Thu, 22 Jul 2021 09:47:31 +0000 Received: from mail-eopbgr00048.outbound.protection.outlook.com ([40.107.0.48] helo=EUR02-AM5-obe.outbound.protection.outlook.com) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1m6VHK-000ys1-Ei; Thu, 22 Jul 2021 09:46:08 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=iM8l22t5cc9VS4WyH2PpS71Fga1x7OzshaXoXIGS8RJQyqwie7hTF4QxzPwrCn0sd2R+A5cmfALy9zCcQ2ZO04k4bijBSPeKmzTp4i+NjeczUw/ongP7uVVOnq68UoATG+wdCPFgnnfn8EkQI/DgL61Sla4ZBHuBwwJXJxbv6HwOzKVmV1FKW6JaWWxM9iJX33ShyxuU7D6LsoKtv0C1ZfmZ+05lGjZ16IOYS5ZiiAS1/rah9GHckucTLnygnABMU76ZmvxW4IJ1fp5C1Cw8hpjPDxQN8XCM3yZVA9A5H1Lrcf30jEEGE1LN+Xl2ctA81e5QEeddWlzZxRnt6/dknw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=GI63k0pfcgubGsH7+yvOVpNphLc/V+RuMjPgnlDlV04=; b=U7EiEn1IbQzZGbKqEb1lTr80ixj0gRCnAqTKwsUTrCpfG20yTSm+kpWsn60YAqEq6u3od5wGRz+YyKoBQQYpV9je6noJyPbciBryvlbavgf14sEXGKyUHcZFFCBE/gcb8BJ13LM6zKU7l34rs/DYIGUItcqrDajC3PO7HLAbsCbqUkq82HMetePb+rP1TUS/HK8RTh9Ip+eg3emIBatFSOoGjOh/gh7IUctbpF+Kq5PZaz5Nkw6nypTLwdtEn/OEY9EBAH/HgTpL9ky1/D1LhqftvvLypySbA2REEFwf1Tj5sFvpkU9NZk6BvBVv7ub208Nki8QxYhzmcEVDb2O4Ig== 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=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=GI63k0pfcgubGsH7+yvOVpNphLc/V+RuMjPgnlDlV04=; b=d14cgVtTbGPoRPnU1Zp+7y7jdD67QBGUHcTKW2Ijpg7Tv6KTg2Dej2Vg7Bt3IAngIhAfJXG74I4Y3pn5MEzJrNTaCewwSPEunvuH2PqWwyHabCLupdxDfee6DSVJVoeBbLkZH5SPIdFtDQAW376LGGinhyc+OwxF+dNL9sT8s0Y= Authentication-Results: gmail.com; dkim=none (message not signed) header.d=none;gmail.com; dmarc=none action=none header.from=nxp.com; Received: from AM7PR04MB7046.eurprd04.prod.outlook.com (2603:10a6:20b:113::22) by AM6PR04MB5208.eurprd04.prod.outlook.com (2603:10a6:20b:9::32) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4331.28; Thu, 22 Jul 2021 09:46:03 +0000 Received: from AM7PR04MB7046.eurprd04.prod.outlook.com ([fe80::8c66:a7b4:1dc7:2c27]) by AM7PR04MB7046.eurprd04.prod.outlook.com ([fe80::8c66:a7b4:1dc7:2c27%8]) with mapi id 15.20.4352.025; Thu, 22 Jul 2021 09:46:03 +0000 Message-ID: <08ca856c013aba60e686f050e06a6e3179de6030.camel@nxp.com> Subject: Re: [PATCH v2 2/3] clk: fractional-divider: Introduce NO_PRESCALER flag From: Liu Ying To: Andy Shevchenko Cc: Andy Shevchenko , Heiko Stuebner , Elaine Zhang , Stephen Boyd , linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, Michael Turquette , NXP Linux Team , Jacky Bai Date: Thu, 22 Jul 2021 17:43:49 +0800 In-Reply-To: References: <20210716133448.24890-1-andriy.shevchenko@linux.intel.com> <20210716133448.24890-2-andriy.shevchenko@linux.intel.com> <9117e5212a3b743ca541918ec2b701c159ac752c.camel@nxp.com> User-Agent: Evolution 3.36.4-0ubuntu1 X-ClientProxiedBy: SGBP274CA0002.SGPP274.PROD.OUTLOOK.COM (2603:1096:4:b0::14) To AM7PR04MB7046.eurprd04.prod.outlook.com (2603:10a6:20b:113::22) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from blueberry (119.31.174.66) by SGBP274CA0002.SGPP274.PROD.OUTLOOK.COM (2603:1096:4:b0::14) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4352.24 via Frontend Transport; Thu, 22 Jul 2021 09:46:00 +0000 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: a0864181-748f-4a9a-8027-08d94cf5851f X-MS-TrafficTypeDiagnostic: AM6PR04MB5208: X-MS-Exchange-Transport-Forked: True X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:10000; X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; 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:AM7PR04MB7046.eurprd04.prod.outlook.com; PTR:; CAT:NONE; SFS:(4636009)(366004)(6496006)(6916009)(7416002)(2906002)(52116002)(53546011)(5660300002)(186003)(956004)(4326008)(316002)(83380400001)(86362001)(2616005)(6666004)(8676002)(66476007)(26005)(508600001)(66556008)(36756003)(38100700002)(6486002)(38350700002)(8936002)(66946007)(54906003); DIR:OUT; SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?cFNvclpnZDRxWDkrOVJzekVxeElvd2xDTTBXc3ovWGpiZ1VVcWNRNG1FN3hz?= =?utf-8?B?YzJjWUVPQkRCcUViV1FsM2tDZm5KWWxMMElSUWhVOEs5Zm9sN2tBYkxhNjhm?= =?utf-8?B?SGFUaFU0S0RSMmg2QXFUNUl6VmdWZkFWTXNSaDdWTXRva2YvazhnRmZHTzlw?= =?utf-8?B?emF5TDVwdUlNMnJFTUdTQUpxRW1EWDg1b3lxVlNrRkovOWFxV1Y2b3RZN0tW?= =?utf-8?B?Y3VyS1lyOWhjbnkwc2VSM3YrMG1JSDIvdzloSHZoK21lb3NnTkF2Qzl4ZVFC?= =?utf-8?B?UkVSU0hvMkgyRnlxUzJ2YzFWa0ljZFZ0OUdERURwUXljVHpoOUZiaUZlVTNP?= =?utf-8?B?MHpseE5weFc4TjVPNzZPRlBqNXVaMzlzVWJIM1JqU1NPTEF5eVozVWNNWmY3?= =?utf-8?B?ZW8yYUhhOUlDU1JzRlppeG1sNHFYeGtlN0ZBcVdKMmh1TStyL3ZCQ0cwU3kr?= =?utf-8?B?VU1COHZCSmdZS3dYN3cyK01mdnR2cXBUVzFBcEx4dFYvbG9SQ2Y1ckRXREEx?= =?utf-8?B?Q0wwN1Zlb0hNRmVZdkF2aFMxemdza0JhOE54NXFMdmlXZlgyVEJvTWtpYzZJ?= =?utf-8?B?Ty84Qm1NLzE3S1BvYklRdFJQR1ZQcExydEFsNGpVTFJnWCtEV2RzRmJoQzd5?= =?utf-8?B?YThxcU42SWYyYXh4cGxIdDBlRjZ0UURwaDQ1N0R6WDRwcXBwSW5va3JobWpj?= =?utf-8?B?RGJuT2lOVDlyVnlXelFwNTh6T2xFRUZ1V2p4eXc3Ynp1ZjBzemJ6bi8zZzMw?= =?utf-8?B?Y3JoakVRQnFHaE50a0c5YmNNVlhzSzUvWHNWRm5vdWhhaDNHZkhiN092QkZB?= =?utf-8?B?UDNXblBkdmJoaS9lZ01GMWJNUTlLU256Y21Ib3BlRjBJMHh4Ny9makNiMXM5?= =?utf-8?B?S21EaC9qYUY5UmhXb0czUDArdVpYWENHT2FoaUtrYURwazBFVXNrT2RKRzdj?= =?utf-8?B?OHVzZlNJVldsRFFEdzlrSmlZY1FFY3dBL3JjMXhxNld1SktQR0lxUWxVVDZr?= =?utf-8?B?TFRzdHhiQzgvQTZsUmtVUW1HblZKN3c5ZkRKdlV0Tlh3T2VsaTZTVjB6d0Fx?= =?utf-8?B?bmoxWWRWcGFDRGpvQ2pRYjk2dGZYaG8zanpvaVhhV05uOHVMTGhEbldHSit3?= =?utf-8?B?NkZOT1J3QnRXSHpDV0tCMjVlS2EzdFgxZmtORjlQemowOFZZZ0VUeVJTdCs0?= =?utf-8?B?U3Y1S2RnVTZhbUxYdnBPNmhKRTVOTFovcWpwelQrOG0vb0pCZDZNUlNkNGxj?= =?utf-8?B?SHNJcFM3MWR4U0pRWXNOc2ZNTkdjOGp6MkRhM1ZuOEdwTHVWM2VxVUdhNmZi?= =?utf-8?B?cVRpVFVnRkpyT25NOVE0S05OKysxUm8vMVJtRWFqb2VKQU9BWHBUQ29WMlhW?= =?utf-8?B?VnNkV3RlT3ArMC81WnFSVm8xWmNrNDFISFhYcnhLbzhrZmd4cjJBM203bVhR?= =?utf-8?B?b3BGZ3Y2WmY2bjNZNWdFcnhMamp4SXVqRCtYcVZCZER0aVREWnBaMTdQSjlw?= =?utf-8?B?SmszS2JwbXJMZDNJV2hQRHFNc0FISXlRQzdFcVZZUUtYU2hvUU14V2trV0J2?= =?utf-8?B?UTlJaWVNMjdDcko1S2QzQldMZFZkV0dMMWFqbng1QXNBSndtR3NGY0ttbUVH?= =?utf-8?B?dGdQWDJXT1diaTQyNWNZR3JNR3RKOU5lQzl6U2lOY0ppcFF1UVZBRmk0eVJa?= =?utf-8?B?TlliQXpTczlsYTNxYnQ5b1VOMFRZVGo0N0NmT1ZUTTQ4NTdpaDBGWVJRUFV5?= =?utf-8?Q?qjgGgExxGIuv4cXP3rIbPsh7NubrFg37ewNzpLU?= X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: a0864181-748f-4a9a-8027-08d94cf5851f X-MS-Exchange-CrossTenant-AuthSource: AM7PR04MB7046.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Jul 2021 09:46:03.4754 (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: 3DkEGy3XH0Rps/tsCSbdhOrjLjdCx1QshJPxYD2MvisfswKgx5m6RRoYTzUBOBP66sf3dmg5jf3YUargkJjvug== X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM6PR04MB5208 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210722_024606_605037_F8DF26DC X-CRM114-Status: GOOD ( 25.85 ) X-BeenThere: linux-rockchip@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Upstream kernel work for Rockchip platforms List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-rockchip" Errors-To: linux-rockchip-bounces+linux-rockchip=archiver.kernel.org@lists.infradead.org On Thu, 2021-07-22 at 12:38 +0300, Andy Shevchenko wrote: > On Thu, Jul 22, 2021 at 12:33 PM Liu Ying wrote: > > On Fri, 2021-07-16 at 16:34 +0300, Andy Shevchenko wrote: > > > The newly introduced flag, when set, makes the flow to skip > > > the assumption that the caller will use an additional 2^scale > > > prescaler to get the desired clock rate. > > > > As I mentioned in v1 comment, it seems to be good to decouple the > > prescaler knowledge from this common fractional divider clk driver. > > This way, we'll make it simpler and easier to maintain. Also, then, the > > NO_PRESCALER flag is not needed at all. However, it seems that two > > Intel drivers which use the frational divider drivers will be affected > > and rate negotiation logics need to be implemented for them. Please > > consider if it's doable or not. > > The current driver works for the certain hardware without this change. > If you think it's better, submit a proposal we will discuss. Well, I'm not afford to do so. Just share an idea. I haven't got the intel HW to test. As I mentioned in v1 comment, it seems that you have experience on relevent drivers and HW to test, may I encourage you to do that :-) Or forget that if you really think you won't do that. > > > If we ultimately keep the prescaler knowledge here, please consider to > > add the NO_PRESCALER flag for i.MX7ulp as it hasn't the prescaler IIUC. > > You mean there is a code which is currently using this driver w/o > taking into account this prescaller flavour? Can you, please, point > out, I'll definitely update it. Thanks for the catch! drivers/clk/imx/clk-composite-7ulp.c Regards, Liu Ying > _______________________________________________ Linux-rockchip mailing list Linux-rockchip@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-rockchip 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 X-Spam-Level: X-Spam-Status: No, score=-5.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MSGID_FROM_MTA_HEADER,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C5482C6377D for ; Thu, 22 Jul 2021 09:49:04 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 95B0A61029 for ; Thu, 22 Jul 2021 09:49:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 95B0A61029 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=nxp.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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:MIME-Version:References:In-Reply-To: Date:Cc:To:From:Subject:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=VfZ4OArtFN0OoO9HEgKuS20grAkIlBNGP8UDd+yuahk=; b=GbyAgHOFN4j5Tz SZgVjEbXjyVIc4Xt+X38tzpnJhTF3O4S954d2XnOwb9kZL99ssXUrZy0blMzw8unmFIH3RAcBXIto +gFltMRc091xlxWCrAJB2rFBqXlwlapbq6kOckROQFU5p8xnWHT9QfPEWVnyBo/uHP5nzZWsePOVl rw3UrIY/nu5JTK7OCtg1GpvmyveQ24709WAD+Ht7xnlT1CuZGG8clmTSW3dyAHe6cSy3BWyVZqZEA f079/HZ7kv3gsYGiJXIzEVbSvmCddFfh9XKR12R1magjUG/QrmXUH6cf+JstkVgoLZHhMsnyDQKLU B8T2GDlt5u0vQV4dQfhQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1m6VIO-000zIv-Ns; Thu, 22 Jul 2021 09:47:13 +0000 Received: from mail-eopbgr00048.outbound.protection.outlook.com ([40.107.0.48] helo=EUR02-AM5-obe.outbound.protection.outlook.com) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1m6VHK-000ys1-Ei; Thu, 22 Jul 2021 09:46:08 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=iM8l22t5cc9VS4WyH2PpS71Fga1x7OzshaXoXIGS8RJQyqwie7hTF4QxzPwrCn0sd2R+A5cmfALy9zCcQ2ZO04k4bijBSPeKmzTp4i+NjeczUw/ongP7uVVOnq68UoATG+wdCPFgnnfn8EkQI/DgL61Sla4ZBHuBwwJXJxbv6HwOzKVmV1FKW6JaWWxM9iJX33ShyxuU7D6LsoKtv0C1ZfmZ+05lGjZ16IOYS5ZiiAS1/rah9GHckucTLnygnABMU76ZmvxW4IJ1fp5C1Cw8hpjPDxQN8XCM3yZVA9A5H1Lrcf30jEEGE1LN+Xl2ctA81e5QEeddWlzZxRnt6/dknw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=GI63k0pfcgubGsH7+yvOVpNphLc/V+RuMjPgnlDlV04=; b=U7EiEn1IbQzZGbKqEb1lTr80ixj0gRCnAqTKwsUTrCpfG20yTSm+kpWsn60YAqEq6u3od5wGRz+YyKoBQQYpV9je6noJyPbciBryvlbavgf14sEXGKyUHcZFFCBE/gcb8BJ13LM6zKU7l34rs/DYIGUItcqrDajC3PO7HLAbsCbqUkq82HMetePb+rP1TUS/HK8RTh9Ip+eg3emIBatFSOoGjOh/gh7IUctbpF+Kq5PZaz5Nkw6nypTLwdtEn/OEY9EBAH/HgTpL9ky1/D1LhqftvvLypySbA2REEFwf1Tj5sFvpkU9NZk6BvBVv7ub208Nki8QxYhzmcEVDb2O4Ig== 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=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=GI63k0pfcgubGsH7+yvOVpNphLc/V+RuMjPgnlDlV04=; b=d14cgVtTbGPoRPnU1Zp+7y7jdD67QBGUHcTKW2Ijpg7Tv6KTg2Dej2Vg7Bt3IAngIhAfJXG74I4Y3pn5MEzJrNTaCewwSPEunvuH2PqWwyHabCLupdxDfee6DSVJVoeBbLkZH5SPIdFtDQAW376LGGinhyc+OwxF+dNL9sT8s0Y= Authentication-Results: gmail.com; dkim=none (message not signed) header.d=none;gmail.com; dmarc=none action=none header.from=nxp.com; Received: from AM7PR04MB7046.eurprd04.prod.outlook.com (2603:10a6:20b:113::22) by AM6PR04MB5208.eurprd04.prod.outlook.com (2603:10a6:20b:9::32) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4331.28; Thu, 22 Jul 2021 09:46:03 +0000 Received: from AM7PR04MB7046.eurprd04.prod.outlook.com ([fe80::8c66:a7b4:1dc7:2c27]) by AM7PR04MB7046.eurprd04.prod.outlook.com ([fe80::8c66:a7b4:1dc7:2c27%8]) with mapi id 15.20.4352.025; Thu, 22 Jul 2021 09:46:03 +0000 Message-ID: <08ca856c013aba60e686f050e06a6e3179de6030.camel@nxp.com> Subject: Re: [PATCH v2 2/3] clk: fractional-divider: Introduce NO_PRESCALER flag From: Liu Ying To: Andy Shevchenko Cc: Andy Shevchenko , Heiko Stuebner , Elaine Zhang , Stephen Boyd , linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, Michael Turquette , NXP Linux Team , Jacky Bai Date: Thu, 22 Jul 2021 17:43:49 +0800 In-Reply-To: References: <20210716133448.24890-1-andriy.shevchenko@linux.intel.com> <20210716133448.24890-2-andriy.shevchenko@linux.intel.com> <9117e5212a3b743ca541918ec2b701c159ac752c.camel@nxp.com> User-Agent: Evolution 3.36.4-0ubuntu1 X-ClientProxiedBy: SGBP274CA0002.SGPP274.PROD.OUTLOOK.COM (2603:1096:4:b0::14) To AM7PR04MB7046.eurprd04.prod.outlook.com (2603:10a6:20b:113::22) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from blueberry (119.31.174.66) by SGBP274CA0002.SGPP274.PROD.OUTLOOK.COM (2603:1096:4:b0::14) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4352.24 via Frontend Transport; Thu, 22 Jul 2021 09:46:00 +0000 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: a0864181-748f-4a9a-8027-08d94cf5851f X-MS-TrafficTypeDiagnostic: AM6PR04MB5208: X-MS-Exchange-Transport-Forked: True X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:10000; X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; 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:AM7PR04MB7046.eurprd04.prod.outlook.com; PTR:; CAT:NONE; SFS:(4636009)(366004)(6496006)(6916009)(7416002)(2906002)(52116002)(53546011)(5660300002)(186003)(956004)(4326008)(316002)(83380400001)(86362001)(2616005)(6666004)(8676002)(66476007)(26005)(508600001)(66556008)(36756003)(38100700002)(6486002)(38350700002)(8936002)(66946007)(54906003); DIR:OUT; SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?cFNvclpnZDRxWDkrOVJzekVxeElvd2xDTTBXc3ovWGpiZ1VVcWNRNG1FN3hz?= =?utf-8?B?YzJjWUVPQkRCcUViV1FsM2tDZm5KWWxMMElSUWhVOEs5Zm9sN2tBYkxhNjhm?= =?utf-8?B?SGFUaFU0S0RSMmg2QXFUNUl6VmdWZkFWTXNSaDdWTXRva2YvazhnRmZHTzlw?= =?utf-8?B?emF5TDVwdUlNMnJFTUdTQUpxRW1EWDg1b3lxVlNrRkovOWFxV1Y2b3RZN0tW?= =?utf-8?B?Y3VyS1lyOWhjbnkwc2VSM3YrMG1JSDIvdzloSHZoK21lb3NnTkF2Qzl4ZVFC?= =?utf-8?B?UkVSU0hvMkgyRnlxUzJ2YzFWa0ljZFZ0OUdERURwUXljVHpoOUZiaUZlVTNP?= =?utf-8?B?MHpseE5weFc4TjVPNzZPRlBqNXVaMzlzVWJIM1JqU1NPTEF5eVozVWNNWmY3?= =?utf-8?B?ZW8yYUhhOUlDU1JzRlppeG1sNHFYeGtlN0ZBcVdKMmh1TStyL3ZCQ0cwU3kr?= =?utf-8?B?VU1COHZCSmdZS3dYN3cyK01mdnR2cXBUVzFBcEx4dFYvbG9SQ2Y1ckRXREEx?= =?utf-8?B?Q0wwN1Zlb0hNRmVZdkF2aFMxemdza0JhOE54NXFMdmlXZlgyVEJvTWtpYzZJ?= =?utf-8?B?Ty84Qm1NLzE3S1BvYklRdFJQR1ZQcExydEFsNGpVTFJnWCtEV2RzRmJoQzd5?= =?utf-8?B?YThxcU42SWYyYXh4cGxIdDBlRjZ0UURwaDQ1N0R6WDRwcXBwSW5va3JobWpj?= =?utf-8?B?RGJuT2lOVDlyVnlXelFwNTh6T2xFRUZ1V2p4eXc3Ynp1ZjBzemJ6bi8zZzMw?= =?utf-8?B?Y3JoakVRQnFHaE50a0c5YmNNVlhzSzUvWHNWRm5vdWhhaDNHZkhiN092QkZB?= =?utf-8?B?UDNXblBkdmJoaS9lZ01GMWJNUTlLU256Y21Ib3BlRjBJMHh4Ny9makNiMXM5?= =?utf-8?B?S21EaC9qYUY5UmhXb0czUDArdVpYWENHT2FoaUtrYURwazBFVXNrT2RKRzdj?= =?utf-8?B?OHVzZlNJVldsRFFEdzlrSmlZY1FFY3dBL3JjMXhxNld1SktQR0lxUWxVVDZr?= =?utf-8?B?TFRzdHhiQzgvQTZsUmtVUW1HblZKN3c5ZkRKdlV0Tlh3T2VsaTZTVjB6d0Fx?= =?utf-8?B?bmoxWWRWcGFDRGpvQ2pRYjk2dGZYaG8zanpvaVhhV05uOHVMTGhEbldHSit3?= =?utf-8?B?NkZOT1J3QnRXSHpDV0tCMjVlS2EzdFgxZmtORjlQemowOFZZZ0VUeVJTdCs0?= =?utf-8?B?U3Y1S2RnVTZhbUxYdnBPNmhKRTVOTFovcWpwelQrOG0vb0pCZDZNUlNkNGxj?= =?utf-8?B?SHNJcFM3MWR4U0pRWXNOc2ZNTkdjOGp6MkRhM1ZuOEdwTHVWM2VxVUdhNmZi?= =?utf-8?B?cVRpVFVnRkpyT25NOVE0S05OKysxUm8vMVJtRWFqb2VKQU9BWHBUQ29WMlhW?= =?utf-8?B?VnNkV3RlT3ArMC81WnFSVm8xWmNrNDFISFhYcnhLbzhrZmd4cjJBM203bVhR?= =?utf-8?B?b3BGZ3Y2WmY2bjNZNWdFcnhMamp4SXVqRCtYcVZCZER0aVREWnBaMTdQSjlw?= =?utf-8?B?SmszS2JwbXJMZDNJV2hQRHFNc0FISXlRQzdFcVZZUUtYU2hvUU14V2trV0J2?= =?utf-8?B?UTlJaWVNMjdDcko1S2QzQldMZFZkV0dMMWFqbng1QXNBSndtR3NGY0ttbUVH?= =?utf-8?B?dGdQWDJXT1diaTQyNWNZR3JNR3RKOU5lQzl6U2lOY0ppcFF1UVZBRmk0eVJa?= =?utf-8?B?TlliQXpTczlsYTNxYnQ5b1VOMFRZVGo0N0NmT1ZUTTQ4NTdpaDBGWVJRUFV5?= =?utf-8?Q?qjgGgExxGIuv4cXP3rIbPsh7NubrFg37ewNzpLU?= X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: a0864181-748f-4a9a-8027-08d94cf5851f X-MS-Exchange-CrossTenant-AuthSource: AM7PR04MB7046.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Jul 2021 09:46:03.4754 (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: 3DkEGy3XH0Rps/tsCSbdhOrjLjdCx1QshJPxYD2MvisfswKgx5m6RRoYTzUBOBP66sf3dmg5jf3YUargkJjvug== X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM6PR04MB5208 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210722_024606_605037_F8DF26DC X-CRM114-Status: GOOD ( 25.85 ) 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 Thu, 2021-07-22 at 12:38 +0300, Andy Shevchenko wrote: > On Thu, Jul 22, 2021 at 12:33 PM Liu Ying wrote: > > On Fri, 2021-07-16 at 16:34 +0300, Andy Shevchenko wrote: > > > The newly introduced flag, when set, makes the flow to skip > > > the assumption that the caller will use an additional 2^scale > > > prescaler to get the desired clock rate. > > > > As I mentioned in v1 comment, it seems to be good to decouple the > > prescaler knowledge from this common fractional divider clk driver. > > This way, we'll make it simpler and easier to maintain. Also, then, the > > NO_PRESCALER flag is not needed at all. However, it seems that two > > Intel drivers which use the frational divider drivers will be affected > > and rate negotiation logics need to be implemented for them. Please > > consider if it's doable or not. > > The current driver works for the certain hardware without this change. > If you think it's better, submit a proposal we will discuss. Well, I'm not afford to do so. Just share an idea. I haven't got the intel HW to test. As I mentioned in v1 comment, it seems that you have experience on relevent drivers and HW to test, may I encourage you to do that :-) Or forget that if you really think you won't do that. > > > If we ultimately keep the prescaler knowledge here, please consider to > > add the NO_PRESCALER flag for i.MX7ulp as it hasn't the prescaler IIUC. > > You mean there is a code which is currently using this driver w/o > taking into account this prescaller flavour? Can you, please, point > out, I'll definitely update it. Thanks for the catch! drivers/clk/imx/clk-composite-7ulp.c Regards, Liu Ying > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel