POST: move CONFIG_POST to Makefiles

Introduce the new logical option CONFIG_HAS_POST which is set when the
platform has CONFIG_POST set. Use CONFIG_HAS_POST in the post/ Makefiles
to determine should the POST libs be compiled for the selected target
platform, or not.

To avoid breaking u-boot linking process, the empty post/libpost.a file is
created for platforms which do not have POSTs.

Signed-off-by: Yuri Tikhonov <yur@emcraft.com>
Signed-off-by: Wolfgang Denk <wd@denx.de>
diff --git a/post/Makefile b/post/Makefile
index f32af95..02b5154 100644
--- a/post/Makefile
+++ b/post/Makefile
@@ -21,11 +21,50 @@
 # MA 02111-1307 USA
 #
 
+include $(TOPDIR)/include/autoconf.mk
 
-SUBDIRS = drivers cpu lib_$(ARCH) board/$(BOARDDIR)
+LIB				= libpost.a
+GPLIB-$(CONFIG_HAS_POST)	+= libgenpost.a
+COBJS-$(CONFIG_HAS_POST)	+= post.o tests.o
 
-LIB	= libpost.a
+SPLIB-$(CONFIG_HAS_POST) = drivers/libpostdrivers.a
+SPLIB-$(CONFIG_HAS_POST) += $(shell if [ -d lib_$(ARCH) ]; then echo \
+			    "lib_$(ARCH)/libpost$(ARCH).a"; fi)
+SPLIB-$(CONFIG_HAS_POST) += $(shell if [ -d lib_$(ARCH)/fpu ]; then echo \
+			    "lib_$(ARCH)/fpu/libpost$(ARCH)fpu.a"; fi)
+SPLIB-$(CONFIG_HAS_POST) += $(shell if [ -d cpu/$(CPU) ]; then echo \
+			    "cpu/$(CPU)/libpost$(CPU).a"; fi)
+SPLIB-$(CONFIG_HAS_POST) += $(shell if [ -d board/$(BOARD) ]; then echo \
+			    "board/$(BOARD)/libpost$(BOARD).a"; fi)
 
-COBJS	= post.o tests.o
+GPLIB	:= $(GPLIB-y)
+SPLIB	:= $(SPLIB-y)
+COBJS	:= $(COBJS-y)
+SRCS	:= $(SOBJS:.o=.S) $(COBJS:.o=.c)
+OBJS	:= $(addprefix $(obj),$(COBJS))
+LIB	:= $(obj)$(LIB)
+
+all:	$(LIB)
+
+# generic POST library
+$(GPLIB): $(obj).depend $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
+
+# specific POST libraries
+$(SPLIB): $(obj).depend
+	$(MAKE) -C $(dir $(subst $(obj),,$@))
+
+# the POST lib archive
+$(LIB): $(GPLIB) $(SPLIB)
+	(echo create $(LIB); for lib in $(GPLIB) $(SPLIB) ; \
+	 do echo addlib $$lib; done; echo save) \
+	| $(AR) -M
+
+#########################################################################
+
+# defines $(obj).depend target
+include $(SRCTREE)/rules.mk
+
+sinclude $(obj).depend
 
-include $(TOPDIR)/post/rules.mk
+#########################################################################