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=-6.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS autolearn=ham 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 1AB47C67839 for ; Thu, 13 Dec 2018 08:03:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DCAA220672 for ; Thu, 13 Dec 2018 08:03:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DCAA220672 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=amlogic.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-clk-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727268AbeLMIDW (ORCPT ); Thu, 13 Dec 2018 03:03:22 -0500 Received: from mail-sh2.amlogic.com ([58.32.228.45]:32582 "EHLO mail-sh2.amlogic.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726995AbeLMIDW (ORCPT ); Thu, 13 Dec 2018 03:03:22 -0500 Received: from [10.18.29.207] (10.18.29.207) by mail-sh2.amlogic.com (10.18.11.6) with Microsoft SMTP Server (TLS) id 15.0.1320.4; Thu, 13 Dec 2018 16:03:40 +0800 Subject: Re: [PATCH RESEND v7 4/4] clk: meson: add one based divider support for sclk divider To: Jerome Brunet , Neil Armstrong CC: Kevin Hilman , Carlo Caione , Michael Turquette , Stephen Boyd , Rob Herring , Miquel Raynal , Boris Brezillon , Martin Blumenstingl , Yixun Lan , Liang Yang , Jian Hu , Qiufang Dai , Hanjie Lin , Victor Wan , , , , References: <1544457877-51301-1-git-send-email-jianxin.pan@amlogic.com> <1544457877-51301-5-git-send-email-jianxin.pan@amlogic.com> <4da764c237b8f752af1dc33a011e2a4b73068f02.camel@baylibre.com> From: Jianxin Pan Message-ID: Date: Thu, 13 Dec 2018 16:03:39 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.3.2 MIME-Version: 1.0 In-Reply-To: <4da764c237b8f752af1dc33a011e2a4b73068f02.camel@baylibre.com> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.18.29.207] X-ClientProxiedBy: mail-sh2.amlogic.com (10.18.11.6) To mail-sh2.amlogic.com (10.18.11.6) Sender: linux-clk-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-clk@vger.kernel.org Hi Jerome, Thanks for the fully review, we really appreciate your time. On 2018/12/12 1:16, Jerome Brunet wrote: > On Tue, 2018-12-11 at 00:04 +0800, Jianxin Pan wrote: >> When CLK_DIVIDER_ONE_BASED flag is set, the sclk divider will be: >> one based divider (div = val), and zero value gates the clock >> >> Signed-off-by: Jianxin Pan >> --- >> drivers/clk/meson/clkc-audio.h | 1 + >> drivers/clk/meson/sclk-div.c | 28 ++++++++++++++++++---------- >> 2 files changed, 19 insertions(+), 10 deletions(-) > > Such a patch should be done earlier in the series, at least before using sclk > in your controller, otherwise thing will be broken in between > I will move it to the first one of the patchset. > In general, I would prefer if you had added two helper function to deal with > the translation between register value and divider value. > > Only these function should care about CLK_DIVIDER_ONE_BASED, the rest should > just call them. > > This, we will be able to deal the with HI (duty cycle) part as well, which you > completly skiped. > > I know your device does not have this, but still the code has to make sense. > OK, I will add two helper for value and register translation, and then appy them to both div and hi. >> >> diff --git a/drivers/clk/meson/clkc-audio.h b/drivers/clk/meson/clkc-audio.h >> index 0a7c157..9bd6ced 100644 >> --- a/drivers/clk/meson/clkc-audio.h >> +++ b/drivers/clk/meson/clkc-audio.h >> @@ -20,6 +20,7 @@ struct meson_sclk_div_data { >> struct parm hi; >> unsigned int cached_div; >> struct clk_duty cached_duty; >> + u8 flags; >> }; >> >> extern const struct clk_ops meson_clk_triphase_ops; >> diff --git a/drivers/clk/meson/sclk-div.c b/drivers/clk/meson/sclk-div.c >> index bc64019..d98707b 100644 >> --- a/drivers/clk/meson/sclk-div.c >> +++ b/drivers/clk/meson/sclk-div.c >> @@ -24,22 +24,23 @@ >> return (struct meson_sclk_div_data *)clk->data; >> } >> >> -static int sclk_div_maxval(struct meson_sclk_div_data *sclk) >> -{ >> - return (1 << sclk->div.width) - 1; >> -} >> - >> static int sclk_div_maxdiv(struct meson_sclk_div_data *sclk) >> { >> - return sclk_div_maxval(sclk) + 1; >> + if (sclk->flags & CLK_DIVIDER_ONE_BASED) >> + return clk_div_mask(sclk->div.width); >> + else >> + return clk_div_mask(sclk->div.width) + 1; > > seems over complicated. > why no call clk_div_mask just once, and add 1 if necessary ? Yes, I will use helper here. > >> } >> >> static int sclk_div_getdiv(struct clk_hw *hw, unsigned long rate, >> unsigned long prate, int maxdiv) >> { >> int div = DIV_ROUND_CLOSEST_ULL((u64)prate, rate); >> + struct clk_regmap *clk = to_clk_regmap(hw); >> + struct meson_sclk_div_data *sclk = meson_sclk_div_data(clk); >> + int mindiv = (sclk->flags & CLK_DIVIDER_ONE_BASED) ? 1 : 2; > > This is why I want helpers, don't like this above OK, I will replace it with helpers. > >> >> - return clamp(div, 2, maxdiv); >> + return clamp(div, mindiv, maxdiv); >> } >> >> static int sclk_div_bestdiv(struct clk_hw *hw, unsigned long rate, >> @@ -47,7 +48,7 @@ static int sclk_div_bestdiv(struct clk_hw *hw, unsigned >> long rate, >> struct meson_sclk_div_data *sclk) >> { >> struct clk_hw *parent = clk_hw_get_parent(hw); >> - int bestdiv = 0, i; >> + int bestdiv = 0, i, mindiv; >> unsigned long maxdiv, now, parent_now; >> unsigned long best = 0, best_parent = 0; >> >> @@ -64,8 +65,9 @@ static int sclk_div_bestdiv(struct clk_hw *hw, unsigned >> long rate, >> * unsigned long in rate * i below >> */ >> maxdiv = min(ULONG_MAX / rate, maxdiv); >> + mindiv = (sclk->flags & CLK_DIVIDER_ONE_BASED) ? 1 : 2; >> >> - for (i = 2; i <= maxdiv; i++) { >> + for (i = mindiv; i <= maxdiv; i++) { >> /* >> * It's the most ideal case if the requested rate can be >> * divided from parent clock without needing to change >> @@ -153,10 +155,14 @@ static int sclk_div_get_duty_cycle(struct clk_hw *hw, >> static void sclk_apply_divider(struct clk_regmap *clk, >> struct meson_sclk_div_data *sclk) >> { >> + unsigned int div; >> + >> if (MESON_PARM_APPLICABLE(&sclk->hi)) >> sclk_apply_ratio(clk, sclk); >> >> - meson_parm_write(clk->map, &sclk->div, sclk->cached_div - 1); >> + div = (sclk->flags & CLK_DIVIDER_ONE_BASED) ? >> + sclk->cached_div : (sclk->cached_div - 1); > > helpers again. OK! > >> + meson_parm_write(clk->map, &sclk->div, div); >> } >> >> static int sclk_div_set_rate(struct clk_hw *hw, unsigned long rate, >> @@ -223,6 +229,8 @@ static void sclk_div_init(struct clk_hw *hw) >> /* if the divider is initially disabled, assume max */ >> if (!val) >> sclk->cached_div = sclk_div_maxdiv(sclk); >> + else if (sclk->flags & CLK_DIVIDER_ONE_BASED) >> + sclk->cached_div = val; >> else >> sclk->cached_div = val + 1; > > same ... OK, I will fix them. Thanks again for your time! > >> > > > . >