Re: Centrino question

Alexander Hoogerhuis
2004-05-25T23:28:11Z

On Fri, 2004-05-21 at 10:38 -0700, Ow Mun Heng wrote:
> On Fri, 2004-05-21 at 04:52, Karol Kozimor wrote:
> > Thus wrote Cyril Wattebled:
> > > However, I don't understand, I was told that the centrino processor and chipset
> > > supports C3 and even C4.
>
> C3 is Supported
>
>
> active state: C2
> default state: C1
> bus master activity: ffffffff
> states:
> C1: promotion[C2] demotion[--] latency[000] usage[01028830]
> *C2: promotion[C3] demotion[C1] latency[050] usage[04785987]
> C3: promotion[--] demotion[C2] latency[050] usage[00001327]
>
> This is a Dell D600 1.4g. c3 values are low because I have the USB mouse
> on right now. (note the fffffff??)
>
> I've tested it with and w/o C3. The difference in the battery lifetime
> was only very minmal. I got like maybe 10 mins extra.
>
> I last 2:30 on Linux and 3h on Windows.
>
> Batt Life Sucks..
>

I've been through tracking down what disables C3 on my laptop (HP
nc6000). It all happens when the uhci-hci USB drviver goes in. When I
queried about it on lkml a while back it was due tro some support
lacking in the UHCI dirvers as of yet.

mvh,
A