From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mike Frysinger <vapier@gentoo.org>
Date: Mon, 28 Jan 2008 21:14:13 -0500
Subject: [U-Boot-Users] [Patch] Disable icache before call the first
	line of kernel in do_bootelf().
In-Reply-To: <20070813155047.C419424041@gemini.denx.de>
References: <20070813155047.C419424041@gemini.denx.de>
Message-ID: <200801282114.14393.vapier@gentoo.org>
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To: u-boot@lists.denx.de

On Monday 13 August 2007, Wolfgang Denk wrote:
> in message <200708131052.44472.vapier@gentoo.org> you wrote:
> > so using weak hooks is OK now ?  i think it'd be good to migrate all of
> > the
>
> It always has been OK - just nobody bothered to use it. [And I didn't
> even know about it when I started working on PPCBoot.]
>
> > ugly boote/bootm/etc... cruft to external weaks and let arches define
> > their own
>
> Yes, a few #ifdef's can be eliminated that way.

unfortunately, using weak symbols and overriding elsewhere doesnt look like 
it's possible currently due to the way ld searches archives.  for example, if 
i do something like:
common/cmd_elf.c:
__attribute__((weak)) do_bootelf_setup() { ... current code ... }
do_bootelf() {
	...
	do_bootelf_setup();
	...

and then i want to override this with a Blackfin version:
lib_blackfin/bootelf_setup.c:
do_bootelf_setup() { ... }

but since the linking process looks like:
ld ... --start-group ... \
	... lib_blackfin/libblackfin.a ... \
	... common/libcommon.a ... \
	--end-group ...
ld will pick the weak symbol provided by libcommon.a even though a strong 
symbol is also available in libblackfin.a :(

so our only realistic options are:
 - create another static archive in common/ for weak symbols and specify it 
just before libcommon.a
 - live with #ifdef's, but minimize the crappy situation by splitting out just 
the relevant code so the main bootelf function stays clean
-mike
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