Bug: Pentium M not always detected by CPUFREQ

Bug: Pentium M not always detected by CPUFREQ

[Holger Schurig]

Hi !

One module thinks that I have a Pentium M, the other doesn't. 
Which module is right?


# modprobe p4-clockmod
p4-clockmod: Warning: Pentium M detected. The speedstep_centrino 
module offers voltage scaling in addition of frequency scaling. 
You should use that instead of p4-clockmod, if possible.
p4-clockmod: P4/Xeon(TM) CPU On-Demand Clock Modulation available

Okay, so I'll try that:

# rmmod p4-clockmod
# modprobe speedstep-centrino
FATAL: Error inserting speedstep_centrino 
(/lib/modules/2.6.19-rc6/kernel/arch/i386/kernel/cpu/cpufreq/speedstep-centrino.ko): 
No such device

# cat /proc/cpuinfo
processor       : 0
vendor_id       : GenuineIntel
cpu family      : 6
model           : 9
model name      : Intel(R) Celeron(R) processor            600MHz
stepping        : 5
cpu MHz         : 598.093
cache size      : 64 KB
fdiv_bug        : no
hlt_bug         : no
f00f_bug        : no
coma_bug        : no
fpu             : yes
fpu_exception   : yes
cpuid level     : 2
wp              : yes
flags           : fpu vme de pse tsc msr mce cx8 apic sep mtrr 
pge mca cmov pat clflush dts acpi mmx fxsr sse sse2 tm pbe
bogomips        : 1196.88


So far I can only say that speedstep-centrino doesn't have an 
entry for a CPU with a mere 600 MHz. May this be the problem?

Re: Bug: Pentium M not always detected by CPUFREQ

[Arjan van de Ven]

On Tue, 2006-11-21 at 16:46 +0100, Holger Schurig wrote:
> Hi !
> 
> One module thinks that I have a Pentium M, the other doesn't. 
> Which module is right?

> model name      : Intel(R) Celeron(R) processor            600MHz
> stepping        : 5
> cpu MHz         : 598.093
> cache size      : 64 KB
> fdiv_bug        : no
> hlt_bug         : no
> f00f_bug        : no
> coma_bug        : no
> fpu             : yes
> fpu_exception   : yes
> cpuid level     : 2
> wp              : yes
> flags           : fpu vme de pse tsc msr mce cx8 apic sep mtrr 
> pge mca cmov pat clflush dts acpi mmx fxsr sse sse2 tm pbe
> bogomips        : 1196.88
> 
> 
> So far I can only say that speedstep-centrino doesn't have an 
> entry for a CPU with a mere 600 MHz. May this be the problem?
> -
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-- 
if you want to mail me at work (you don't), use arjan (at) linux.intel.com
Test the interaction between Linux and your BIOS via http://www.linuxfirmwarekit.org

Re: Bug: Pentium M not always detected by CPUFREQ

[Arjan van de Ven]

On Tue, 2006-11-21 at 16:46 +0100, Holger Schurig wrote:
> Hi !
> 
> One module thinks that I have a Pentium M, the other doesn't. 
> Which module is right?
> # cat /proc/cpuinfo
> processor       : 0
> vendor_id       : GenuineIntel
> cpu family      : 6
> model           : 9
> model name      : Intel(R) Celeron(R) processor            600MHz

you don't have a pentium M

> stepping        : 5
> cpu MHz         : 598.093
> cache size      : 64 KB
> fdiv_bug        : no
> hlt_bug         : no
> f00f_bug        : no
> coma_bug        : no
> fpu             : yes
> fpu_exception   : yes
> cpuid level     : 2
> wp              : yes
> flags           : fpu vme de pse tsc msr mce cx8 apic sep mtrr 
> pge mca cmov pat clflush dts acpi mmx fxsr sse sse2 tm pbe
> bogomips        : 1196.88
> 
> 
> So far I can only say that speedstep-centrino doesn't have an 
> entry for a CPU with a mere 600 MHz. May this be the problem
> ?

as far as I know Celeron processors don't have actual frequency control
capabilities (and no p4-clockmod doesn't count, that doesn't save you
any energy realistically)....



-- 
if you want to mail me at work (you don't), use arjan (at) linux.intel.com
Test the interaction between Linux and your BIOS via http://www.linuxfirmwarekit.org

Re: Bug: Pentium M not always detected by CPUFREQ

[Holger Schurig]

> you don't have a pentium M

In that case p4-clockmod has a bug, because it said that I have 
one.

Re: Bug: Pentium M not always detected by CPUFREQ

[Dominik Brodowski]

On Wed, Nov 22, 2006 at 08:48:03AM +0100, Holger Schurig wrote:
> > you don't have a pentium M
> 
> In that case p4-clockmod has a bug, because it said that I have 
> one.

That bug should be fixed in -mm, cpufreq-git and 2.6.20.

Thanks,
	Dominik