[U-Boot] confused ... how do some CONFIG settings "implicitly" set others?

Robert P. J. Day rpjday at crashcourse.ca
Fri Nov 20 20:08:05 CET 2009


On Fri, 20 Nov 2009, Wolfgang Denk wrote:

> Dear "Robert P. J. Day",
>
> In message <alpine.LFD.2.00.0911200826340.27923 at localhost> you wrote:
> >
> >   reading http://www.denx.de/wiki/view/DULG/UBootSplashScreen, and i
> > see:
> >
> > "To enable splash screen support, you have to add a "#define
> > CONFIG_SPLASH_SCREEN" to your board configuration file. This will also
> > implicitly enable U-Boot Bitmap Support."
> >
> >   "implicitly"?  how does that work?  from what i can see in
> > define2mk.sed, the transformation is straightforward and there are no
> > dependencies or selects as in the kernel Kconfig structure.  how does
> > setting splash screen implicitly set bitmap support?  what am i
> > missing?
>
> Simple. The relevant parts of the code use
>
> 	#if defined(CONFIG_CMD_BMP) || defined(CONFIG_SPLASH_SCREEN)
>
> so they get selected when CONFIG_CMD_BMP and/or CONFIG_SPLASH_SCREEN
> is defined.

  ok, i get it, but that's not "implicit," that's *explicit*.
totally different meaning.

rday
--


========================================================================
Robert P. J. Day                               Waterloo, Ontario, CANADA

            Linux Consulting, Training and Kernel Pedantry.

Web page:                                          http://crashcourse.ca
Twitter:                                       http://twitter.com/rpjday
========================================================================


More information about the U-Boot mailing list