On Thursday 13 Feb 2020 at 11:59:56 (+0000), Valentin Schneider wrote:

On 2/11/20 6:45 PM, Ionela Voinescu wrote:

quoted

+/**
+ * cpufreq_get_hw_max_freq - get the max hardware frequency of the CPU
+ * @cpu: CPU number
+ *
+ * The default return value is the max_freq field of cpuinfo.
+ */
+__weak unsigned int cpufreq_get_hw_max_freq(unsigned int cpu)
+{
+	struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
+	unsigned int ret_freq = 0;
+
+	if (policy) {
+		ret_freq = policy->cpuinfo.max_freq;
+		cpufreq_cpu_put(policy);

What about intel_pstate / turbo stuff? IIRC one of Giovanni's issues was that
turbo freq is not always reported as the max freq. Dunno if we can do
anything about it; at the very least maybe document the caveat?

Okay, I can add details in the description in regards to potential
reasons to overwrite this function. But basically this is one of the
reasons for making this a weak function. The best information we can
generically get for maximum hardware frequency is cpuinfo.max_freq.
But if platforms have the possibility to obtain this differently from
either hardware or firmware they can overwrite this.

Thanks,
Ionela.

quoted

+	}
+
+	return ret_freq;
+}
+EXPORT_SYMBOL(cpufreq_get_hw_max_freq);
+
 static unsigned int __cpufreq_get(struct cpufreq_policy *policy)
 {
 	if (unlikely(policy_is_inactive(policy)))

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