[PATCH] MIPS: start.S depends on banner

[Sascha Hauer]

On Wed, Sep 16, 2015 at 10:50:33AM +0300, Antony Pavlov wrote:
> On Wed, 16 Sep 2015 14:40:48 +0800
> Kevin Du Huanpeng <u74147 at gmail.com> wrote:
> 
> > Signed-off-by: Kevin Du Huanpeng <u74147 at gmail.com>
> > ---
> >  arch/mips/Kconfig | 1 +
> >  1 file changed, 1 insertion(+)
> > 
> > diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
> > index aeb5c04..fde4c2e 100644
> > --- a/arch/mips/Kconfig
> > +++ b/arch/mips/Kconfig
> > @@ -6,6 +6,7 @@ config MIPS
> >  	select HAS_KALLSYMS
> >  	select HAVE_CONFIGURABLE_MEMORY_LAYOUT
> >  	select HAVE_CONFIGURABLE_TEXT_BASE
> > +	select BANNER
> >  	default y
> >  
> >  config SYS_SUPPORTS_BIG_ENDIAN
> > -- 
> > 1.9.1
> > 
> 
> IMHO we can make banner use in start.S optional. E.g.:
> 
> diff --git a/arch/mips/boot/start.S b/arch/mips/boot/start.S
> index 7e2ae5e..f3a6a00 100644
> --- a/arch/mips/boot/start.S
> +++ b/arch/mips/boot/start.S
> @@ -22,8 +22,10 @@
>  #include <asm/mipsregs.h>
>  #include <asm/asm.h>
>  #include <asm-generic/memory_layout.h>
> +#ifdef CONFIG_BANNER
>  #include <generated/compile.h>
>  #include <generated/utsrelease.h>
> +#endif

CONFIG_BANNER and this compilation failure have nothing to do with each
other.

The problem we have is that start.S may get compiled before
generated/compile.h is generated. This is because there is no
Make dependency from start.S to generated/compile.h. Look at
common/Makefile. There we have:

$(obj)/version.o: include/generated/compile.h

This makes sure that generated/compile.h is generated before compiling
version.c.

In arch/mips/boot/Makefile we would need:

$(obj)/start.o: include/generated/compile.h

The problem is that we do not have the rule to generate compile.h
available in this Makefile, so we would also need:

       chk_compile.h = :
 quiet_chk_compile.h = echo '  CHK     $@'
silent_chk_compile.h = :
include/generated/compile.h: FORCE
	@$($(quiet)chk_compile.h)
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkcompile_h $@ \
	"$(UTS_MACHINE)" "$(CC) $(KBUILD_CFLAGS)"

in arch/mips/boot/Makefile.

Sascha

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