Re: Enabling power states for Core 2 Duo

From: Robert Hancock
Date: Tue May 22 2007 - 10:27:05 EST


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@xxxxxxxxxxxxx
Home Page: http://www.roberthancock.com/

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