Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753945Ab3IMQPo (ORCPT ); Fri, 13 Sep 2013 12:15:44 -0400 Received: from caramon.arm.linux.org.uk ([78.32.30.218]:54684 "EHLO caramon.arm.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751624Ab3IMQPn (ORCPT ); Fri, 13 Sep 2013 12:15:43 -0400 Date: Fri, 13 Sep 2013 17:15:28 +0100 From: Russell King - ARM Linux To: Viresh Kumar Cc: "Rafael J. Wysocki" , Lists linaro-kernel , Patch Tracking , "cpufreq@vger.kernel.org" , "linux-pm@vger.kernel.org" , Linux Kernel Mailing List , "linux-arm-kernel@lists.infradead.org" Subject: Re: [PATCH 206/228] cpufreq: sa11x0: remove calls to cpufreq_notify_transition() Message-ID: <20130913161527.GE12758@n2100.arm.linux.org.uk> References: <6e2ca86ce948c0bc35f7709baf22672771fcf1e8.1379063063.git.viresh.kumar@linaro.org> <20130913155424.GB12758@n2100.arm.linux.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.19 (2009-01-05) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2005 Lines: 47 On Fri, Sep 13, 2013 at 09:42:23PM +0530, Viresh Kumar wrote: > On 13 September 2013 21:24, Russell King - ARM Linux > wrote: > > On Fri, Sep 13, 2013 at 06:32:32PM +0530, Viresh Kumar wrote: > >> Most of the drivers do following in their ->target_index() routines: > >> > >> struct cpufreq_freqs freqs; > >> freqs.old = old freq... > >> freqs.new = new freq... > >> > >> cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE); > >> > >> /* Change rate here */ > >> > >> cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE); > >> > >> This is replicated over all cpufreq drivers today and there doesn't exists a > >> good enough reason why this shouldn't be moved to cpufreq core instead. > >> > >> Earlier patches have added support in cpufreq core to do cpufreq notification on > >> frequency change, this one removes it from this driver. > >> > >> Some related minor cleanups are also done along with it. > >> > >> Cc: Russell King > >> Signed-off-by: Viresh Kumar > > > > Shouldn't this patch set CPUFREQ_ASYNC_NOTIFICATION somewhere? > > As far as I can see, sa11x0 completes frequency transition from within > target() and so it does it synchronously.. And so it doesn't need to set > CPUFREQ_ASYNC_NOTIFICATION... > > Am I missing something? The patch to which I'm replying removes the above calls. These calls are necessary to shutdown various bits of CPU-clock dependent hardware before changing the CPU clock, and restore them - reconfiguring them for the new clock rate after the transition has happened. So, if you're removing these calls, what replaces them? I don't see anything which does without the above set. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/