The previous commit introduced a useful macro used in makefiles,
in order to reference to different variables (CONFIG_... or
CONFIG_SPL_...) depending on the build context.
Per-image config option control is a PITA in C sources, too.
Here are some macros useful in C/CPP expressions.
CONFIG_IS_ENABLED(FOO) can be used as a shorthand for
(!defined(CONFIG_SPL_BUILD) && defined(CONFIG_FOO)) || \
(defined(CONFIG_SPL_BUILD) && defined(CONFIG_SPL_FOO))
For example, it is useful to describe C code as follows,
#if CONFIG_IS_ENABLED(OF_CONTROL)
(device tree code)
#else
(board file code)
#endif
The ifdef conditional above is switched by CONFIG_OF_CONTROL during
the U-Boot proper building (CONFIG_SPL_BUILD is not defined), and by
CONFIG_SPL_OF_CONTROL during SPL building (CONFIG_SPL_BUILD is
defined).
The macro can be used in C context as well, so you can also write the
equivalent code as follows:
if (CONFIG_IS_ENABLED(OF_CONTROL)) {
(device tree code)
} else {
(board file code)
}
Another useful macro is CONFIG_VALUE().
CONFIG_VALUE(FOO) is expanded into CONFIG_FOO if CONFIG_SPL_BUILD is
undefined, and into CONFIG_SPL_FOO if CONFIG_SPL_BUILD is defined.
You can write as follows:
text_base = CONFIG_VALUE(TEXT_BASE);
instead of:
#ifdef CONFIG_SPL_BUILD
text_base = CONFIG_SPL_TEXT_BASE;
#else
text_base = CONFIG_TEXT_BASE;
#endif
This commit also adds slight hacking on fixdep so that it can
output a correct list of fixed dependencies.
If the fixdep finds CONFIG_IS_ENABLED(FOO) in a source file,
we want
$(wildcard include/config/foo.h)
in the U-boot proper building context, while we want
$(wildcard include/config/spl/foo.h)
in the SPL build context.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
