[ltp] Re: T410 does not have a power state below C3

Henrique de Moraes Holschuh linux-thinkpad@linux-thinkpad.org
Sun, 19 Dec 2010 18:31:02 -0200

On Wed, 15 Dec 2010, Pedro Ribeiro wrote:
> Sorry for the insistence, but this is severely impacting my battery
> life, as well as creating a lot of heat.
> Does anyone here with a T410 have the same problem?
> Henrique, what's your take on this?

Try using a new kernel, with the intel-idle driver (instead of
acpi-idle).  Don't bother with whichever C-state it will list, it is
probably false with that driver but it should try the best possible
idling.  Might hang Lenovo's BIOS, so do a first-time careful test (e.g.
boot read-only and wait a bit to see if it will hang).

Other than that, I don't know.  Try unloading uhci-hcd and ehci-hcd,
etc.  See if intel's new version of powertop is available anywhere, and
try it, etc.

If nothing else works, bring in the large guns.  Compile a perf kernel
and look in the web about instructions on how to use the perf tool, then
use it to find out WTF is keeping the system up all the time.

  "One disk to rule them all, One disk to find them. One disk to bring
  them all and in the darkness grind them. In the Land of Redmond
  where the shadows lie." -- The Silicon Valley Tarot
  Henrique Holschuh