Re: Enabling power states for Core 2 Duo

[Robert Hancock <hancockr@shaw.ca>]

Paa Paa wrote:
> For some reason I'm not able to enable processor power states (c1, c2 
> etc.) for my Core 2 Duo. This is what I get::
>
> cat /proc/acpi/processor/CPU1/info
> processor id:            0
> acpi id:                 1
> bus mastering control:   no
> power management:        no
> throttling control:      no
> limit interface:         no
>
> cat /proc/acpi/processor/CPU1/power
> active state:            C0
> max_cstate:              C8
> bus master activity:     00000000
> maximum allowed latency: 2000 usec
> states:
>
> "dmesg | grep -i power" also gives nothing. I have ACPI enabled in BIOS 
> and in kernel I have these set ("grep -i acpi .config | grep =y"):
>
> CONFIG_ACPI=y
> CONFIG_ACPI_PROCESSOR=y
> CONFIG_ACPI_THERMAL=y
> CONFIG_ACPI_EC=y
> CONFIG_ACPI_POWER=y
> CONFIG_ACPI_SYSTEM=y
> CONFIG_X86_ACPI_CPUFREQ=y
> CONFIG_PNPACPI=y
> CONFIG_SATA_ACPI=y
>
> I'm probably missing something crucial here. So how do I enable power 
> states? I'm using 64-bit Gentoo. My mobo is Asus P5B Deluxe. Otherwise 
> ACPI works fine.

The BIOS has to expose this support in ACPI, if it doesn't (which is 
often the case on desktop boards) you won't get any C-state support 
(well, except for C1 which is just the normal halt state).

--
Robert Hancock      Saskatoon, SK, Canada
To email, remove "nospam" from hancockr@nospamshaw.ca
Home Page: http://www.roberthancock.com/

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