idle patches for 2.6.38-rc7

Hi Linus,

please pull from:

git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6.git idle-release

This will update the files shown below.

thanks!

Len Brown
Intel Open Source Technology Center

 arch/x86/include/asm/msr-index.h |    5 +++++
 drivers/idle/intel_idle.c        |   24 ++++++++++++++++++++++++
 2 files changed, 29 insertions(+), 0 deletions(-)

through these commits:

Len Brown (2):
intel_idle: disable NHM/WSM HW C-state auto-demotion
intel_idle: disable Atom/Lincroft HW C-state auto-demotion

with this log:

commit bfb53ccf1c734b1907df7189eef4c08489827951

Author: Len Brown <[email protected]>
Date:   Wed Feb 16 01:32:48 2011 -0500

intel_idle: disable Atom/Lincroft HW C-state auto-demotion

Just as we had to disable auto-demotion for NHM/WSM, we need to do the same for Atom (Lincroft version).

In particular, auto-demotion will prevent Lincroft from entering the S0i3 idle power saving state.

https://bugzilla.kernel.org/show_bug.cgi?id=25252

commit 14796fca2bd22acc73dd0887248d003b0f441d08

Author: Len Brown <[email protected]>
Date:   Tue Jan 18 20:48:27 2011 -0500

intel_idle: disable NHM/WSM HW C-state auto-demotion

Hardware C-state auto-demotion is a mechanism where the HW overrides the OS C-state request, instead demoting to a shallower state, which is less expensive, but saves less power.

Modern Linux should generally get exactly the states it requests. In particular, when a CPU is taken off-line, it must not be demoted, else it can prevent the entire package from reaching deep C-states.

https://bugzilla.kernel.org/show_bug.cgi?id=25252