mpc5121: add common post_word_load/store code

Add common post_word_load/post_word_store routines
for all mpc5121 boards. pdm360ng board POST support
added by subsequent patch needs them.

Signed-off-by: Anatolij Gustschin <agust@denx.de>

arch/powerpc/cpu/mpc512x/Makefile

@@ -29,6 +29,7 @@ LIB	= $(obj)lib$(CPU).a
 START	= start.o
 COBJS-y	:= cpu.o
 COBJS-y	+= traps.o
+COBJS-y += common.o
 COBJS-y += cpu_init.o
 COBJS-y += fixed_sdram.o
 COBJS-y += i2c.o

arch/powerpc/cpu/mpc512x/common.c

@@ -0,0 +1,25 @@
+#include <common.h>
+#include <asm/io.h>
+
+#if defined(CONFIG_POST) || defined(CONFIG_LOGBUFFER)
+
+#if defined(CONFIG_SYS_POST_WORD_ADDR)
+# define _POST_ADDR	(CONFIG_SYS_POST_WORD_ADDR)
+#else
+#error echo "No POST word address defined"
+#endif
+
+void post_word_store(ulong a)
+{
+	volatile void *save_addr = (volatile void *)(_POST_ADDR);
+
+	out_be32(save_addr, a);
+}
+
+ulong post_word_load(void)
+{
+	volatile void *save_addr = (volatile void *)(_POST_ADDR);
+
+	return in_be32(save_addr);
+}
+#endif  /* CONFIG_POST || CONFIG_LOGBUFFER */