frequency scaling on D525MW not working properly

Sepherosa Ziehau sepherosa at
Sun Jul 22 18:44:06 PDT 2012

On Mon, Jul 23, 2012 at 3:27 AM, Sascha Wildner <saw at> wrote:
> On Sun, 22 Jul 2012 21:16:54 +0200, Sven Gaerner <sgaerner at> wrote:
>> On Sun, Jul 22, 2012 at 08:31:41PM +0200, Sascha Wildner wrote:
>>> On Sun, 22 Jul 2012 13:46:41 +0200, Sven Gaerner <sgaerner at>
>>> wrote:
>>> >[...]
>>> >Also there is no sysctl available,
>>> >so I guess powerd is also running not properly and the CPU
>>> >frequency is not
>>> >scaled in any way. After looking into the dmesg output, I guess
>>> >some driver does
>>> >not recognize parts of the hardware/ACPI stuff correctly (see
>>> >below; the text is
>>> >repeated for the other 3 logical CPUs). cpu0: on acpi0 cpu_cst0:
>>> >on cpu0 cpu_pst0:
>>> >Can't get _PSS package - AE_NOT_FOUND The dmesg is attached. It
>>> >would be great
>>> >if there is someone who can help me to get this fixed. If more
>>> >details are
>>> >necessary, just let me know. Sven
>>> Is this a mobo with UEFI?
>>> Sascha
>> Yes, but booting via UEFI is disabled.

Hmm, disabling UEFI is OK, but make sure that you have enabled EST in
BIOS (something probably read like "enhanced speed step" or something
like "P-state").

Besides CPU P-State, you could also set allowable CPU C-State to C3 by
setting sysctl hw.acpi.cpu.cx_lowest and put tunable
hw.i8254.intr_disable="0" in /boot/loader.conf (you need to reboot
after changing /boot/loader.conf).  However, it should be noted that
enabling C3 will disable LAPIC timer and i8254 timer will be used
instead, which may cause extra overhead.

Best Regards,

Tomorrow Will Never Die

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