[U-Boot] What is the correct way to configure SPL options?

[Charles Manning <manningc2@actrix.gen.nz>]

On Friday 18 May 2012 08:58:06 Scott Wood wrote:
> On 05/17/2012 03:47 PM, Tom Rini wrote:
> > On 05/17/2012 01:22 PM, Scott Wood wrote:
> >> We had problems with (B) regarding TEXT_BASE -- the makefile versions of
> >> the config symbols will only be generated once.
> >> CONFIG_SKIP_LOW_LEVEL_INIT doesn't seem to be used from makefiles.
> >>
> >> I still think (C) is the way to go.
> >
> > But since we have CONFIG_SYS_SPL_TEXT_BASE now, (B) is how we do it
> > normally, yes?
>
> That was more of an instance of "OK, I give in, we'll do it the simple
> but ugly way if it's just this one thing" than "the normal way".
>

To me it looks like the ugliness comes from an unclear policy resulting in SPL 
configs being handled in two different ways.

IMHO, the policy can be simplified and rationalised in two ways:


A) Recognise name each config option that might vary with an SPL and regular 
variant. That will just lead to hell in the Makefiles.
- non inclusive or-
C) Each binary has a different config and is built separately. Then there is 
no need for multiple CONFIGs for the same feature.

I have found (C) to work fine for building multiple variants (using a much 
older version of u-boot). For example, I build two stripped u-boots to run a 
manufacturing loader process. I thus build at least 3 different u-boots for 
the same board. Each has a different config and is built separately.

I guess common stuff can be rationalised:
foo-common.h
....

foo-uboot.h
#include "foo-common.h"
...

foo-spl.h
#include "foo-common.h"
...

But that really makes for config file proliferation. Still, that would seem 
more manageable.

-- CHarles