Re: Invalid detection CPU frequency ?

В вт, 27/09/2005 в 16:35 -0700, Nate Lawson пишет:
> Vladimir Grebenschikov wrote:
> > It looks strange but sometimes my notebook start on full-speed (1.7GHz)
> > and sysctls output looks like:
> > 
> > dev.cpu.0.freq: 1687
> > dev.cpu.0.freq_levels: 1687/-1 1476/-1 1265/-1 1054/-1 843/-1 632/-1 421/-1 210/-1
> > dev.acpi_throttle.0.%desc: ACPI CPU Throttling
> > 
> > And sometimes it starts on low speed (~500 Mhz)
> > dev.cpu.0.freq: 595
> > dev.cpu.0.freq_levels: 595/-1 520/-1 446/-1 371/-1 297/-1 223/-1 148/-1 74/-1
> > dev.acpi_throttle.0.%desc: ACPI CPU Throttling
> 
> > And speed can't be raised by powerd or other.
> > Looks like it happens when notebook stats or shutdowns on batteries.
> > Rebooting on AC power cures situation. But anyway - I do not think it is normal.
> > 
> > Any suggestions ? 
> 
> It's very simple.  You have an old notebook that only supports 
> throttling, not SpeedStep or other options.  Your BIOS sets the initial 
> speed based on AC line status on boot.  If you look at your CPU 
> announcement at the top of dmesg, it will show 595 Mhz or whatever since 
> it uses a simple calibration loop.
> 
> I might consider always setting 100% in the attach routine for 
> acpi_throttle and p4tcc to get proper probe values.  You'll still have a 
> problem if you use the TSC timecounter since it's only calibrated at boot.

Nate, thanks for explanation, is loading cpufreq.ko from loader is good
solution ? Or I will still have TSC problems ? 

-- 
Vladimir B. Grebenschikov
SWsoft Inc. vova_at_swsoft.com