Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750896AbdHLEtu (ORCPT ); Sat, 12 Aug 2017 00:49:50 -0400 Received: from hermes.aosc.io ([199.195.250.187]:43668 "EHLO hermes.aosc.io" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750761AbdHLEtt (ORCPT ); Sat, 12 Aug 2017 00:49:49 -0400 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Date: Sat, 12 Aug 2017 12:49:46 +0800 From: icenowy@aosc.io To: Chen-Yu Tsai Cc: Mark Rutland , devicetree , Jonathan Liu , Priit Laes , Michael Turquette , Stephen Boyd , Russell King , linux-kernel , linux-sunxi , Rob Herring , Philipp Zabel , Maxime Ripard , linux-clk , linux-arm-kernel Subject: Re: [linux-sunxi] Re: [PATCH v6 1/6] clk: sunxi-ng: div: Add support for fixed post-divider In-Reply-To: References: <946794e97ae2c36cd67c272099e8236a589efc28.1500043741.git-series.plaes@plaes.org> <20170717085235.i7pwwql5dgmnf6kk@flea> Message-ID: <1c52cfe1ac634f01ea386fef6b1b525b@aosc.io> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2842 Lines: 84 在 2017-08-12 12:13，Chen-Yu Tsai 写道： > On Sat, Aug 12, 2017 at 11:07 AM, wrote: >> 在 2017-07-17 16:52，Maxime Ripard 写道： >>> >>> On Fri, Jul 14, 2017 at 05:49:23PM +0300, Priit Laes wrote: >>>> >>>> SATA clock on sun4i/sun7i is of type (parent) / M / 6 where >>>> 6 is fixed post-divider. >>>> >>>> Signed-off-by: Priit Laes >>>> --- >>>> drivers/clk/sunxi-ng/ccu_div.c | 15 +++++++++++++-- >>>> drivers/clk/sunxi-ng/ccu_div.h | 3 ++- >>>> 2 files changed, 15 insertions(+), 3 deletions(-) >>>> >>>> diff --git a/drivers/clk/sunxi-ng/ccu_div.c >>>> b/drivers/clk/sunxi-ng/ccu_div.c >>>> index c0e5c10..744502a 100644 >>>> --- a/drivers/clk/sunxi-ng/ccu_div.c >>>> +++ b/drivers/clk/sunxi-ng/ccu_div.c >>>> @@ -21,6 +21,9 @@ static unsigned long ccu_div_round_rate(struct >>>> ccu_mux_internal *mux, >>>> { >>>> struct ccu_div *cd = data; >>>> >>>> + if (cd->common.features & CCU_FEATURE_FIXED_POSTDIV) >>>> + rate *= cd->fixed_post_div; >>>> + >>>> return divider_round_rate_parent(&cd->common.hw, parent, >>>> rate, parent_rate, >>>> cd->div.table, >>>> cd->div.width, >>> >>> >>> >>> You still haven't addressed the biggest issue with this patch, see: >>> https://patchwork.kernel.org/patch/9825565/ >> >> >> I think he has already did the changes suggested in the review. > > Nope. Only half of it is fixed. First you "unapply" the post-divider, > i.e. multiply the rate by the divider. Then you pass it to > divider_round_rate_parent. You still have to reapply the divider > to the result. This last part is missing. This means the clock > rate returned by ccu_div_round_rate is going to be off. > > Instead the return statement should be > > return divider_round_rate_parent(...) / cd->fixed_post_div Oh, got it by reading other CCU clock types that has fixed postdiv. Thanks! > > ChenYu > >> >> (P.S. during developing R40 CCU driver I found that pll-periph0-sata >> also needs this patch, so I'm rechecking it) >> >>> >>> Maxime >>> >>> _______________________________________________ >>> linux-arm-kernel mailing list >>> linux-arm-kernel@lists.infradead.org >>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel >> >> >> -- >> You received this message because you are subscribed to the Google >> Groups >> "linux-sunxi" group. >> To unsubscribe from this group and stop receiving emails from it, send >> an >> email to linux-sunxi+unsubscribe@googlegroups.com. >> For more options, visit https://groups.google.com/d/optout. > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel