PowerOP, Intro 0/3

What's changed highlights:

- PowerOP Core is completely arch independent
- PowerOP Core provides interface to create/destroy, get/set operating points
- PowerOP Core maintains list of operating points which can be referenced by names
- PowerOP Core allows an upper layer to operate on arbitrary subset of power parameters available on a certain platform
- More integration with cpufreq and omap cpufreq driver clean up (hw access code is removed)

PowerOP is a system power parameter management API submitted for discussion.

This patch set is a follow-up to the PowerOP/cpufreq integration discussion in the PM summit back in April and the continued discussion of the small PM group and linux-pm list.

Overall proposed PM framework picture is the following:

user space
-----------------------------------------------------------------

        ----------                                      kernel space
     | CPU freq |
       ----------        
          ^                
           |                
          v              

------------------------
| PowerOP |
-------------------------
arch independent
------------------------------------------------------------------------
arch specific
--------------------------
| PM Core |
-------------------------
------------------------------
| Clock/Voltage FW |
------------------------------

In the whole, PowerOP is designed to be completely arch independent and and allows to create, write and read power parameters in a form adopted by a layer above PowerOP (cpufreq for example).

PM Core provides access to all power parameters available on a certain platform and in a pair with PowerOP allows for a power control layer above PowerOP operates by arbitrary subset of power parameters (cpufreq for ex. uses 2 out of 8 power parameters available on an omap1 platform what will be shown in follow-up patch but one can imaging other layer which utilize from 1 upto 8 power parameters).

Nowadays Linux has clock framework - well established interface to access hw clocks and the layer which handles clocks interdependencies. Similar voltage framework is on the way. Such combined clock/voltage framework provides a good interface to get/set clock and voltage hw registers. Clock/voltage framework utilization gives significant advantage in power management providing dynamic clocks/voltages control in addition to "on demand" power parameters settings capability provided by PowerOP.

This reference implementation is an example of integrating cpufreq and PowerOP on the OMAP 1710.