kbuild: allow assignment to {A,C,LD}FLAGS_MODULE on the command line

It is now possible to assign options to AS, CC and LD
on the command line - which is only used when building modules.

{A,C,LD}FLAGS_MODULE was all used both in the top-level Makefile
in the arch makefiles, thus users had no way to specify
additional options to AS, CC, LD when building modules
without overriding the original value.

Introduce a new set of variables KBUILD_{A,C,LD}FLAGS_MODULE
that is used by arch specific files and free up
{A,C,LD}FLAGS_MODULE so they can be assigned on
the command line.

All arch Makefiles that used the old variables has been updated.

Note: Previously we had a MODFLAGS variable for both
AS and CC. But in favour of consistency this was dropped.
So in some cases arch Makefile has one assignmnet replaced by
two assignmnets.

Note2: MODFLAGS was not documented and is dropped
without any notice. I do not expect much/any breakage
from this.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Acked-by: Mike Frysinger <vapier@gentoo.org> [blackfin]
Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> [avr32]
Signed-off-by: Michal Marek <mmarek@suse.cz>

2 files changed, 10 insertions, 6 deletions

diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index 390aae4bb222..5e7c40e16545 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -115,7 +115,10 @@ endif
 # ---------------------------------------------------------------------------
 
 # Default is built-in, unless we know otherwise
-modkern_cflags = $(if $(part-of-module), $(CFLAGS_MODULE), $(CFLAGS_KERNEL))
+modkern_cflags =                                          \
+	$(if $(part-of-module),                           \
+		$(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \
+		$(CFLAGS_KERNEL))
 quiet_modtag := $(empty)   $(empty)
 
 $(real-objs-m)        : part-of-module := y
@@ -250,8 +253,8 @@ $(obj)/%.lst: $(src)/%.c FORCE
 
 modkern_aflags := $(AFLAGS_KERNEL)
 
-$(real-objs-m)      : modkern_aflags := $(AFLAGS_MODULE)
-$(real-objs-m:.o=.s): modkern_aflags := $(AFLAGS_MODULE)
+$(real-objs-m)      : modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
+$(real-objs-m:.o=.s): modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
 
 quiet_cmd_as_s_S = CPP $(quiet_modtag) $@
 cmd_as_s_S       = $(CPP) $(a_flags)   -o $@ $< 
diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost
index 8f14c81abbc7..3e3f02409bbd 100644
--- a/scripts/Makefile.modpost
+++ b/scripts/Makefile.modpost
@@ -107,7 +107,7 @@ $(modules:.ko=.mod.c): __modpost ;
 modname = $(notdir $(@:.mod.o=))
 
 quiet_cmd_cc_o_c = CC      $@
-      cmd_cc_o_c = $(CC) $(c_flags) $(CFLAGS_MODULE)	\
+      cmd_cc_o_c = $(CC) $(c_flags) $(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE) \
 		   -c -o $@ $<
 
 $(modules:.ko=.mod.o): %.mod.o: %.mod.c FORCE
@@ -117,8 +117,9 @@ targets += $(modules:.ko=.mod.o)
 
 # Step 6), final link of the modules
 quiet_cmd_ld_ko_o = LD [M]  $@
-      cmd_ld_ko_o = $(LD) -r $(LDFLAGS) $(LDFLAGS_MODULE) -o $@		\
-			  $(filter-out FORCE,$^)
+      cmd_ld_ko_o = $(LD) -r $(LDFLAGS)                                 \
+                             $(KBUILD_LDFLAGS_MODULE) $(LDFLAGS_MODULE) \
+                             -o $@ $(filter-out FORCE,$^)
 
 $(modules): %.ko :%.o %.mod.o FORCE
 	$(call if_changed,ld_ko_o)