Re: cpufreq limits avilable frequencies to 800MHz on git kernel

From: Andrew Morton
Date: Fri May 23 2008 - 21:25:41 EST


On Fri, 23 May 2008 19:44:57 +0200 Arkadiusz Miskiewicz <arekm@xxxxxxxx> wrote:

> thinkpad z60m, Intel(R) Pentium(R) M processor 2.00GHz. kernel from git from
> 1-2 days ago.
>
> Unfortunately it seems that suspend to ram/resume causes frequency
> to be limited to 800MHz only. I can't set it to 2GHz again :-/
>
> scaling_max_freq is then 800000 and cannot be changed.
>
> reboot and the problem disappears until new suspend/resume cycle.
>
> cpufreq stuff is driven by acpi-cpufreq
>
> $ cpufreq-info
> cpufrequtils 002: cpufreq-info (C) Dominik Brodowski 2004-2006
> Report errors and bugs to linux@xxxxxxxx, please.
> analyzing CPU 0:
> driver: acpi-cpufreq
> CPUs which need to switch frequency at the same time: 0
> hardware limits: 800 MHz - 2.00 GHz
> available frequency steps: 2.00 GHz, 1.60 GHz, 1.33 GHz, 1.07 GHz, 800 MHz
> available cpufreq governors: powersave, userspace, ondemand, performance
> current policy: frequency should be within 800 MHz and 800 MHz.
> The governor "performance" may decide which speed to use
> within this range.
> current CPU frequency is 800 MHz.
>
> /sys/devices/system/cpu/cpu0/cpufreq/affected_cpus:0
> /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_cur_freq:800000
> /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq:2000000
> /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_min_freq:800000
> /sys/devices/system/cpu/cpu0/cpufreq/related_cpus:0
> /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies:2000000
> 1600000 1333000 1066000 800000
> /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_governors:powersave
> userspace ondemand performance
> /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq:800000
> /sys/devices/system/cpu/cpu0/cpufreq/scaling_driver:acpi-cpufreq
> /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor:performance
> /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq:800000
> /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq:800000
> /sys/devices/system/cpu/cpu0/cpufreq/scaling_setspeed:<unsupported>

Thanks. Is this a newly-occurring bug or did earlier kernels do this also?

If it was newly added, do you know in which kernel version we might
have added it?

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