Blackfin: make sure mmiowb inserts a write barrier with SSYNC
Add SSYNC to our implementation of I/O write barrier to ensure ordering
of I/O space writes. This will make sure that writes following the
barrier will arrive after all previous writes.
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
diff --git a/arch/blackfin/include/asm/io.h b/arch/blackfin/include/asm/io.h
index 29e55b9..234fbac 100644
--- a/arch/blackfin/include/asm/io.h
+++ b/arch/blackfin/include/asm/io.h
@@ -124,7 +124,13 @@
#define iowrite16(val, x) writew(val, x)
#define iowrite32(val, x) writel(val, x)
-#define mmiowb() wmb()
+/**
+ * I/O write barrier
+ *
+ * Ensure ordering of I/O space writes. This will make sure that writes
+ * following the barrier will arrive after all previous writes.
+ */
+#define mmiowb() do { SSYNC(); wmb(); } while (0)
#define IO_SPACE_LIMIT 0xffffffff