[U-Boot] [PATCH 2/2 RESEND] SPL: Allow user to disable CPU support library

[Marek Vasut]

On Tuesday, September 20, 2011 11:23:01 PM Scott Wood wrote:
> On 09/20/2011 04:16 PM, Marek Vasut wrote:
> > On Tuesday, September 20, 2011 09:12:08 PM Scott Wood wrote:
> >> On 09/19/2011 05:31 PM, Marek Vasut wrote:
> >>> Then you adjust the makefile there by ifdef CONFIG_SPL_BUILD
> >> 
> >> It's not quite that simple, since different SPLs will have different
> >> requirements.  Board config headers will need to define symbols like
> >> CONFIG_SPL_FEATURE and the makefiles will use both CONFIG_SPL_BUILD and
> >> CONFIG_SPL_FEATURE to determine which object files to include.
> > 
> > That kind of granularity is there already too -- though on driver level.
> > But so far it seem sufficient.
> 
> What's wrong with using that model for arch code as well?
> 
> Note that "so far" most of the existing SPL targets have not been
> converted to the new spl/.

Right, so when you hit the problem, you fix it. No need to overengineer it right 
away.
> 
> >>>> Whether it's file or directory based, everything should be off by
> >>>> default.  Boards should ask for what they want, not what they want to
> >>>> exclude.
> >>> 
> >>> Actually, this being a rare case where you want it excluded, it's
> >>> better the way it is.
> >> 
> >> I disagree, especially in the early stages where we're setting an
> >> example for how other components will be handled.
> > 
> > No, it's really rare if you want to replace your lowlevel init code
> > because your ROM seems strange.
> 
> It's not about rarity (which is often misjudged, BTW).  It's about
> whether the model for selecting code for the SPL is additive or
> subtractive, and whether we have a consistent mechanism or ad hockery
> from the start.
> 
> In nand_spl/ it was fully additive.  I'd like to keep it that way.

I see your point and I disagree. I'd use the majority vote here -- most of the 
boards need it and rare ones don't -- so why put additional burden on majority 
in favor of minority ?

> 
> -Scott