sysctl: dev.cpu.0.freq: Device busy (cpufreq p4tcc / RELENG_6)

Marcus Alves Grando mnag at FreeBSD.org
Tue Feb 28 16:48:04 PST 2006


Well, works. Thanks. It's possible to printf some message about this if 
kern.timecounter.hardware != ACPI-fast? Or add message in cpufreq(4)?

Thanks

Nate Lawson wrote:
> Marcus Alves Grando wrote:
>> I have problems in cpufreq in RELENG_6 (today).
>>
>> I try to set another frequency in my laptop and get this error:
>>
>> # sysctl dev.cpu.0.freq=250
>> dev.cpu.0.freq: 2000
>> sysctl: dev.cpu.0.freq: Device busy
>>
>> Timecounter "TSC" frequency 1995011972 Hz quality 800
>> Timecounters tick every 1.000 msec
> 
> Try setting your timecounter to acpi or i8254 (not TSC):
> 
> sysctl kern.timecounter.hardware="acpi"
> 
> Without complicated recalibration code (which no one has written yet), 
> we can't base our system time off the TSC counter when cpufreq is 
> changing it.
> 

-- 
Marcus Alves Grando
marcus(at)corp.grupos.com.br  |  Grupos Internet S/A
   mnag(at)FreeBSD.org         |  FreeBSD.org


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