Messages in this thread | | | Subject | Re: [PATCH 0/4] CPUFreq statistics retrieved by drivers | From | Florian Fainelli <> | Date | Tue, 4 Aug 2020 10:27:13 -0700 |
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On 7/29/2020 8:12 AM, Lukasz Luba wrote: > Hi all, > > The existing CPUFreq framework does not tracks the statistics when the > 'fast switch' is used or when firmware changes the frequency independently > due to e.g. thermal reasons. However, the firmware might track the frequency > changes and expose this to the kernel.
Or the firmware might have changed the CPU frequency in response to a request from the secure world for instance.
> > This patch set aims to introduce CPUfreq statistics gathered by firmware > and retrieved by CPUFreq driver. It would require a new API functions > in the CPUFreq, which allows to poke drivers to get these stats.
From a debugging perspective, it would be helpful if the firmware maintained statistics were exposed as a super-set of the Linux cpufreq statistics and aggregated into them such that you could view the normal world vs. secure world residency of a given frequency point. This would help because a lot of times, Linux requests freq X, but the secure world requires freq Y (with X >= Y) and people do not really understand why the resulting power usage is higher for instance.
What are your thoughts on this? -- Florian
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