From 8a487a4417221412d1cd23d4e08253fc9413be51 Mon Sep 17 00:00:00 2001
From: Simon Glass <sjg@chromium.org>
Date: Wed, 10 Oct 2012 13:12:53 +0000
Subject: [PATCH] x86: Add initial memory barrier macros
These are available on other architectures, so add them on x86.
Signed-off-by: Simon Glass <sjg@chromium.org>
---
arch/x86/include/asm/io.h | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h
index 9b757d489e..b12bdd8e2b 100644
--- a/arch/x86/include/asm/io.h
+++ b/arch/x86/include/asm/io.h
@@ -234,4 +234,12 @@ static inline phys_addr_t virt_to_phys(void * vaddr)
return (phys_addr_t)(vaddr);
}
+/*
+ * TODO: The kernel offers some more advanced versions of barriers, it might
+ * have some advantages to use them instead of the simple one here.
+ */
+#define dmb() __asm__ __volatile__ ("" : : : "memory")
+#define __iormb() dmb()
+#define __iowmb() dmb()
+
#endif
--
2.39.5