From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Rafael J. Wysocki" Subject: Re: [PATCH] cpufreq: scmi: Fix frequency invariance in slow path Date: Wed, 09 Jan 2019 11:56:06 +0100 Message-ID: <5435767.4D6MIGYIVi@aspire.rjw.lan> References: <20190109104236.6532-1-quentin.perret@arm.com> <20190109104511.mi3gtdcytkky4eyn@vireshk-i7> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Return-path: In-Reply-To: <20190109104511.mi3gtdcytkky4eyn@vireshk-i7> Sender: linux-kernel-owner@vger.kernel.org To: Viresh Kumar , Quentin Perret Cc: sudeep.holla@arm.com, linux-arm-kernel@lists.infradead.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, dietmar.eggemann@arm.com, qais.yousef@arm.com List-Id: linux-pm@vger.kernel.org On Wednesday, January 9, 2019 11:45:11 AM CET Viresh Kumar wrote: > On 09-01-19, 10:42, Quentin Perret wrote: > > The scmi-cpufreq driver calls the arch_set_freq_scale() callback on > > frequency changes to provide scale-invariant load-tracking signals to > > the scheduler. However, in the slow path, it does so while specifying > > the current and max frequencies in different units, hence resulting in a > > broken freq_scale factor. > > > > Fix this by passing all frequencies in KHz, as stored in the CPUFreq > > frequency table. > > > > Fixes: 99d6bdf33877 ("cpufreq: add support for CPU DVFS based on SCMI > > message protocol") > > Signed-off-by: Quentin Perret > > --- > > drivers/cpufreq/scmi-cpufreq.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/cpufreq/scmi-cpufreq.c b/drivers/cpufreq/scmi-cpufreq.c > > index 50b1551ba894..3f0693439486 100644 > > --- a/drivers/cpufreq/scmi-cpufreq.c > > +++ b/drivers/cpufreq/scmi-cpufreq.c > > @@ -52,9 +52,9 @@ scmi_cpufreq_set_target(struct cpufreq_policy *policy, unsigned int index) > > int ret; > > struct scmi_data *priv = policy->driver_data; > > struct scmi_perf_ops *perf_ops = handle->perf_ops; > > - u64 freq = policy->freq_table[index].frequency * 1000; > > + u64 freq = policy->freq_table[index].frequency; > > > > - ret = perf_ops->freq_set(handle, priv->domain_id, freq, false); > > + ret = perf_ops->freq_set(handle, priv->domain_id, freq * 1000, false); > > if (!ret) > > arch_set_freq_scale(policy->related_cpus, freq, > > policy->cpuinfo.max_freq); > > Acked-by: Viresh Kumar This would be stable-candidate I guess?