cpufreq: scmi: Fix frequency invariance in slow path
authorQuentin Perret <quentin.perret@arm.com>
Wed, 9 Jan 2019 10:42:36 +0000 (10:42 +0000)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 16 Jan 2019 21:04:29 +0000 (22:04 +0100)
commit 0e141d1c65c1dd31c914eb2e11651adcc1a15912 upstream.

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 <quentin.perret@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Cc: 4.17+ <stable@vger.kernel.org> # v4.17+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/cpufreq/scmi-cpufreq.c

index 50b1551..3f06934 100644 (file)
@@ -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);