mips: introduce asm/swab.h

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/mips/include/asm/swab.h b/arch/mips/include/asm/swab.h
new file mode 100644
index 0000000..88f1f7d
--- /dev/null
+++ b/arch/mips/include/asm/swab.h
@@ -0,0 +1,55 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1996, 99, 2003 by Ralf Baechle
+ */
+#ifndef _ASM_SWAB_H
+#define _ASM_SWAB_H
+
+#include <linux/compiler.h>
+#include <asm/types.h>
+
+#define __SWAB_64_THRU_32__
+
+#ifdef CONFIG_CPU_MIPSR2
+
+static inline __attribute_const__ __u16 __arch_swab16(__u16 x)
+{
+	__asm__(
+	"	wsbh	%0, %1			\n"
+	: "=r" (x)
+	: "r" (x));
+
+	return x;
+}
+#define __arch_swab16 __arch_swab16
+
+static inline __attribute_const__ __u32 __arch_swab32(__u32 x)
+{
+	__asm__(
+	"	wsbh	%0, %1			\n"
+	"	rotr	%0, %0, 16		\n"
+	: "=r" (x)
+	: "r" (x));
+
+	return x;
+}
+#define __arch_swab32 __arch_swab32
+
+#ifdef CONFIG_CPU_MIPS64_R2
+static inline __attribute_const__ __u64 __arch_swab64(__u64 x)
+{
+	__asm__(
+	"	dsbh	%0, %1\n"
+	"	dshd	%0, %0"
+	: "=r" (x)
+	: "r" (x));
+
+	return x;
+}
+#define __arch_swab64 __arch_swab64
+#endif /* CONFIG_CPU_MIPS64_R2 */
+#endif /* CONFIG_CPU_MIPSR2 */
+#endif /* _ASM_SWAB_H */