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=-2.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,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 50942C6377D for ; Thu, 22 Jul 2021 09:39:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 399E66120C for ; Thu, 22 Jul 2021 09:39:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231512AbhGVI6X (ORCPT ); Thu, 22 Jul 2021 04:58:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35310 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231463AbhGVI6U (ORCPT ); Thu, 22 Jul 2021 04:58:20 -0400 Received: from mail-pl1-x636.google.com (mail-pl1-x636.google.com [IPv6:2607:f8b0:4864:20::636]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D08A6C061757; Thu, 22 Jul 2021 02:38:55 -0700 (PDT) Received: by mail-pl1-x636.google.com with SMTP id n11so3811614plc.2; Thu, 22 Jul 2021 02:38:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=MuMbiBM7YxAW87DH+qAJXu3APZbrJ75lW5QQXZfYU58=; b=ajsfwRT77Z9EbNaVAyA9I8jZs3BGroEX6WOi0qane/rs14eli9dewk2pAfpz8+X5HS MtTAhJ3j3UMZtcKTjtMbrdMlDq4vi4gEFeAr5GGCf9oj0s0nsIySOKsw5sJ3uLrmZe2X fWnADyjgnxDkNTOKTTe6JJwAQ4tWVdd45f7bdxhe0j6LEklVk+8g+6nC4mUvoV8VH42A Jm5q1MDUiggF8dXIMqceZCBG1atwLlxTwjXsXQO+OIGu2HE/LYCygEdiC9ujPfhBfNMk xMAvjfxjs1ABEdRKz1lCug4NiQhmW7udUIUERo8jaeNy+VN4p5Fukn+ygkd9UkRwLJV5 DvAg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=MuMbiBM7YxAW87DH+qAJXu3APZbrJ75lW5QQXZfYU58=; b=sIN920SrEtUo770T4MAwEGtM5AeGUdp6kgmbFef/IMoS67FIRGfNoO0WsPJy2gGlSw VZLQlIkTJsVzFjxUT/b5Wyx/9qd8ycDlVkgKMmj15YC8fkUze4MwH22cYgitxJy2XUSH Iwx9jsPtvmRVqo8eZlUANIiDfHT+SZp9UAql17nSZ8+XD7Pw52xe5aJMzibZwKHWx8JJ HHfYPI6FIfIuyN+3EQ4tDilrZcW6AnFch29RaSHgXOkusS5vqtCGiyOZsQ7lKomGX2r7 kSaYRrc6Z67b1OQ4KxMof4Vc0jb7ITsxWyOvPW0EMsBPH87K6FtfoZl+BReW7MjXJ8a5 4w4Q== X-Gm-Message-State: AOAM532Da/d2mP/hbv3nr+nysCHNBgKNZLT7NHMVvKQ93jPvto1Kr3vg yZEghl19RzkTVRdplvBKtQvtjJLXi8DzJeu+Reo= X-Google-Smtp-Source: ABdhPJyzhzXA/hG7Rr1mBzyRkHYgREWpgxUI1OzzB5MR3T7ZAB+Szt3xEBP3jbpwYoMfsgxa8AtdYgJHpcudOKg+mKE= X-Received: by 2002:a63:5a5b:: with SMTP id k27mr40486739pgm.74.1626946735354; Thu, 22 Jul 2021 02:38:55 -0700 (PDT) MIME-Version: 1.0 References: <20210716133448.24890-1-andriy.shevchenko@linux.intel.com> <20210716133448.24890-2-andriy.shevchenko@linux.intel.com> <9117e5212a3b743ca541918ec2b701c159ac752c.camel@nxp.com> In-Reply-To: <9117e5212a3b743ca541918ec2b701c159ac752c.camel@nxp.com> From: Andy Shevchenko Date: Thu, 22 Jul 2021 12:38:15 +0300 Message-ID: Subject: Re: [PATCH v2 2/3] clk: fractional-divider: Introduce NO_PRESCALER flag To: Liu Ying 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 Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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. > 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! -- With Best Regards, Andy Shevchenko