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    Subjectsetting cpu speed on crusoe
    Date
    Junichi Morita and I have worked out how to access the crusoe
    "longrun" settings on the crusoe based VAIO. This allows you to enable
    power saving mode and slow the cpu down. It should help battery life a
    lot.

    the following will enable power saving and set the cpu to the slowest
    speed:

    setpci -s 0:0.0 a8.b=11

    and this will restore you to max speed:

    setpci -s 0:0.0 a8.b=0e

    the bits are:

    LRON bit0: long run "on" - I'm not really sure what this does
    LRRV bit1-3: cpu speed
    LREN bit4: seems to enable variable speed

    the info came from a dump of the AML off the box like this:

    00001e24: Scope PCI0 (\_SB_.PCI0)
    00001e30: OpRegion LRCR (\_SB_.PCI0.LRCR)
    00001e36: PCI_Config
    00001e37: 0xa8
    00001e39: 0x04
    00001e3b: Field
    00001e3e: LRCR (00001e30)
    00001e42: AccessType: ByteAcc; LockRule: NoLock; UpdateRule: Preserve
    00001e43: NamedField (1 bits at 0x0:0) LRON
    00001e48: NamedField (3 bits at 0x0:1) LRRV
    00001e4d: NamedField (1 bits at 0x0:4) LREN

    the patch to acpidisasm to give the bit offsets and lengths for named
    fields is available from
    http://www.samba.org/ftp/unpacked/picturebook/acpi.patch





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