ppc4xx simple vs SoC's

[Josh Boyer]

On Thu, Dec 1, 2011 at 12:39 AM, Benjamin Herrenschmidt
<benh at kernel.crashing.org> wrote:
> Hi Josh !
>
> I was helping Tony with some of the Currituck stuff when I noticed an
> oddity...
>
> So we have various "SoC" config symbols such as 440EP, 460SX, etc...
> that in turn select various bits & pieces that enable support for that
> SoC (such as EMAC4 support or FPU support). Those only act as "enables"
> for compiling of the code, there is still going to be a runtime check of
> course.
>
> Those SoC config symbols are not user selectable, they are meant to be
> themselves select'ed by the board Kconfig entries.

Yep, and they are.

> However, the entry for ppc44x_simple doesn't select any of these,
> meaning for example, AFAIK, that you don't get EMAC4 etc... I'm
> surprised things work at all !
>
> What am I missing ?

CONFIG_PPC44x_SIMPLE is selected by the board Kconfig values, which
also select all of the SoC Kconfig options they need as well.
ppc44x_simple started as a way to basically avoid duplicating a bunch
of board.c files, but it's still "driven" from the board options.

So hopefully that explains how things are working today.  The question
now is whether you would like something different?

josh