Overhaul speedstep code

This adds proper support for turbo and super-low-frequency modes.
Calculation of the p-states has been rewritten and moved into an
extra file speedstep.c so it can be used for non-acpi stuff like
EMTTM table generation.

It has been tested with a Core2Duo T9400 (Penryn) and a Core Duo T2300
(Yonah) processor.

Change-Id: I5f7104fc921ba67d85794254f11d486b6688ecec
Signed-off-by: Nico Huber <nico.huber@secunet.com>
Reviewed-on: http://review.coreboot.org/1658
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
4 files changed