[PATCH][POWERPC] QE: Make QUICC Engine support a configurableoption

[Li Yang-r58472]

> >>>>>>  arch/powerpc/Kconfig                |    8 --------
> >>>>>>  arch/powerpc/platforms/83xx/Kconfig |   12 ++++++++++--
> >>>>>>  2 files changed, 10 insertions(+), 10 deletions(-)
> >>>>>
> >>>>> What about 85xx QE support?
> >>>>
> >>>> Kumar and I talked about it.  85xx support will be added when QE
> >>>> works
> >>> on 85xx.
> >>>> However,
> >>>> the patch still needs changes.  To allow each CPU family to have
> > its
> >>> own QE option,
> >>>> we'll
> >>>> need to define something like QUICC_ENGINE_83xx and
> >>>> QUICC_ENGINE_85xx,
> >>> and then
> >>>> have
> >>>> something like this:
> >>>>
> >>>> config QUICC_ENGINE
> >>>> 	bool
> >>>> 	default y if QUICC_ENGINE_83xx || QUICC_ENGINE_85xx
> >>>
> >>> I don't think we need these new options.  If there are differences
> >>> between the two SOC versions, presumably not too many, we can
> > address
> >>> them in device tree.  It's better to leave the QUICC_ENGINE option
> > at
> >>> arch/powerpc/Kconfig level, IMHO.
> >>
> >>
> >> The issue isn't dealing with differences between 83xx/85xx.  Its
> >> allowing the choice for only those two subarchs.
> >
> > If you want to make it configurable, I suggest we put it under the
> > "Processor Support" menu in arch/powerpc/Kconfig like Altivec and
SPE.
> > It is a chip feature rather than board.  And we won't need the two
> > redundant options then.
> 
> Both of those are features of the Core processor, not the platform.
> 
> I'd prefer this be a platform option.  (I'm not a fan of the
> duplication, but its minor)

Well, that depends on how we define processor.  Is co-processor also a
processor?  

QE is so generic that can be used across different sub-archs maybe even
archs.  Why doesn't it deserve a place out of "platform support" menu?
An option in the top menu is another choice.

On another thought, it is very unlikely that user chooses a more
expensive chip with QE and won't use it.  So make it non-configurable
and be selected automatically is not a bad idea for me.

- Leo