From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751492AbcLEKot (ORCPT ); Mon, 5 Dec 2016 05:44:49 -0500 Received: from fllnx210.ext.ti.com ([198.47.19.17]:17553 "EHLO fllnx210.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751096AbcLEKoq (ORCPT ); Mon, 5 Dec 2016 05:44:46 -0500 Subject: Re: [PATCH v3 3/3] ARM: da850: fix da850_set_pll0rate() To: Bartosz Golaszewski , Kevin Hilman , Michael Turquette , Peter Ujfalusi , Russell King , Viresh Kumar , Boris Brezillon , "Rafael J. Wysocki" , Richard Weinberger , David Woodhouse , Brian Norris , Marek Vasut , Cyrille Pitchen References: <1480932549-30811-1-git-send-email-bgolaszewski@baylibre.com> <1480932549-30811-4-git-send-email-bgolaszewski@baylibre.com> CC: LKML , arm-soc , From: Sekhar Nori Message-ID: Date: Mon, 5 Dec 2016 16:13:42 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <1480932549-30811-4-git-send-email-bgolaszewski@baylibre.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Monday 05 December 2016 03:39 PM, Bartosz Golaszewski wrote: > This function is confusing - its second argument is an index to the > freq table, not the requested clock rate in Hz, but it's used as the > set_rate callback for the pll0 clock. It leads to an oops when the > caller doesn't know the internals and passes the rate in Hz as > argument instead of the cpufreq index since this argument isn't bounds > checked either. > > Fix it by iterating over the array of supported frequencies and > selecting a one that matches or returning -EINVAL for unsupported > rates. > > Also: update the davinci cpufreq driver. It's the only user of this > clock and currently it passes the cpufreq table index to > clk_set_rate(), which is confusing. Make it pass the requested clock > rate in Hz. > > Signed-off-by: Bartosz Golaszewski > Acked-by: Viresh Kumar > --- > arch/arm/mach-davinci/da850.c | 20 ++++++++++++++++---- > drivers/cpufreq/davinci-cpufreq.c | 2 +- > 2 files changed, 17 insertions(+), 5 deletions(-) > > diff --git a/arch/arm/mach-davinci/da850.c b/arch/arm/mach-davinci/da850.c > index 006ec56..9837541 100644 > --- a/arch/arm/mach-davinci/da850.c > +++ b/arch/arm/mach-davinci/da850.c > @@ -1179,14 +1179,26 @@ static int da850_set_armrate(struct clk *clk, unsigned long index) > return clk_set_rate(pllclk, index); > } > > -static int da850_set_pll0rate(struct clk *clk, unsigned long index) > +static int da850_set_pll0rate(struct clk *clk, unsigned long rate) > { > - unsigned int prediv, mult, postdiv; > - struct da850_opp *opp; > struct pll_data *pll = clk->pll_data; > + struct cpufreq_frequency_table *freq; > + unsigned int prediv, mult, postdiv; > + struct da850_opp *opp = NULL; > int ret; > > - opp = (struct da850_opp *) cpufreq_info.freq_table[index].driver_data; > + for (freq = da850_freq_table; > + freq->frequency != CPUFREQ_TABLE_END; freq++) { > + /* rate is in Hz, freq->frequency is in KHz */ > + if (freq->frequency == rate / 1000) { Or rate = rate / 1000; before the loop begins? The idea behind my comment was mostly to reduce the amount of calculation in the loop. Thanks, Sekhar