Re: Build failure: bisected: v3.1-rc1 with config ARCH_OMAP && !ARCH_OMAP4 fails with linker error

[Tony Lindgren <tony@atomide.com>]

* Paul Walmsley <paul@pwsan.com> [110809 23:51]:
> On Tue, 9 Aug 2011, Paul Walmsley wrote:
> 
> > On Tue, 9 Aug 2011, Tony Lindgren wrote:
> > 
> > > Hmm, there are also these when CONFIG_ARCH_OMAP4 is not selected:
> > > 
> > > arch/arm/mach-omap2/built-in.o: In function `_enable_module':
> > > arch/arm/mach-omap2/omap_hwmod.c:701: undefined reference to `omap4_cminst_module_enable'
> > > arch/arm/mach-omap2/built-in.o: In function `_disable_module':
> > > arch/arm/mach-omap2/omap_hwmod.c:726: undefined reference to `omap4_cminst_module_disable'
> > > arch/arm/mach-omap2/built-in.o: In function `_wait_target_disable':
> > > arch/arm/mach-omap2/omap_hwmod.c:1179: undefined reference to `omap4_cminst_wait_module_idle'
> > > distcc[27594] ERROR: compile (null) on localhost failed
> > > make: *** [.tmp_vmlinux1] Error 1
> > > 
> > > Care to take a look?
> > 
> > Weird, those don't show up on my n800 config (below) with CodeSourcery 
> > 2010.09-50.  Looks like something isn't removing the dead code.  will post 
> > a patch for this.
> > 
> > If you post which compiler you're using, I'll add it to my build tests 
> > too...
> 
> Hmmm, playing around with this further, this is probably not a
> compiler problem.  Looks like what triggers this is the MULTI_OMAP2
> preprocessor trickery in arch/arm/plat-omap/include/plat/cpu.h, which
> would cause something like cpu_is_omap24xx() to be resolved at runtime
> rather than by the preprocessor.
> 
> This should fix the immediate issue.  Will include in a 3.1-rc fixes branch.

Thanks yes that does the trick. I'd like to queue this immediately so we
have more time to look at the other fixes if you don't mind.

I noticed some checkpatch warnings, updated patch below. Does that look
OK to you?

Tony


From: Paul Walmsley <paul@pwsan.com>
Date: Wed, 10 Aug 2011 00:57:42 -0600
Subject: [PATCH] OMAP: hwmod: fix build break on non-OMAP4 multi-OMAP2 builds

Builds for multi-OMAP2 (e.g., OMAP2420 with OMAP2430) with
CONFIG_ARCH_OMAP4=n fail with the following errors:

arch/arm/mach-omap2/built-in.o: In function `_enable_module':
arch/arm/mach-omap2/omap_hwmod.c:701: undefined reference to `omap4_cminst_module_enable'
arch/arm/mach-omap2/built-in.o: In function `_disable_module':
arch/arm/mach-omap2/omap_hwmod.c:726: undefined reference to `omap4_cminst_module_disable'
arch/arm/mach-omap2/built-in.o: In function `_wait_target_disable':
arch/arm/mach-omap2/omap_hwmod.c:1179: undefined reference to `omap4_cminst_wait_module_idle'

This is probably due to the preprocessor directives in
arch/arm/plat-omap/include/plat/cpu.h that convert some cpu_is_omap*()
expressions from preprocessor directives into something that is only
resolvable during runtime, if multiple OMAP2 build targets are
selected.

Thanks to Tony Lindgren <tony@atomide.com> for reporting.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

diff --git a/arch/arm/mach-omap2/cminst44xx.h b/arch/arm/mach-omap2/cminst44xx.h
index f2ea645..a018a73 100644
--- a/arch/arm/mach-omap2/cminst44xx.h
+++ b/arch/arm/mach-omap2/cminst44xx.h
@@ -18,13 +18,36 @@ extern void omap4_cminst_clkdm_force_sleep(u8 part, s16 inst, u16 cdoffs);
 extern void omap4_cminst_clkdm_force_wakeup(u8 part, s16 inst, u16 cdoffs);
 
 extern int omap4_cminst_wait_module_ready(u8 part, u16 inst, s16 cdoffs, u16 clkctrl_offs);
-extern int omap4_cminst_wait_module_idle(u8 part, u16 inst, s16 cdoffs, u16 clkctrl_offs);
+
+# ifdef CONFIG_ARCH_OMAP4
+extern int omap4_cminst_wait_module_idle(u8 part, u16 inst, s16 cdoffs,
+					 u16 clkctrl_offs);
 
 extern void omap4_cminst_module_enable(u8 mode, u8 part, u16 inst, s16 cdoffs,
 				       u16 clkctrl_offs);
 extern void omap4_cminst_module_disable(u8 part, u16 inst, s16 cdoffs,
 					u16 clkctrl_offs);
 
+# else
+
+static inline int omap4_cminst_wait_module_idle(u8 part, u16 inst, s16 cdoffs,
+					u16 clkctrl_offs)
+{
+	return 0;
+}
+
+static inline void omap4_cminst_module_enable(u8 mode, u8 part, u16 inst,
+				s16 cdoffs, u16 clkctrl_offs)
+{
+}
+
+static inline void omap4_cminst_module_disable(u8 part, u16 inst, s16 cdoffs,
+				 u16 clkctrl_offs)
+{
+}
+
+# endif
+
 /*
  * In an ideal world, we would not export these low-level functions,
  * but this will probably take some time to fix properly