crypto: octeon - add instruction definitions for MD5

Add instruction definitions for MD5. Based on information extracted
from EdgeRouter Pro GPL source tarball.
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

arch/mips/cavium-octeon/crypto/octeon-crypto.h

@@ -4,14 +4,70 @@
  * for more details.
  *
  * Copyright (C) 2012-2013 Cavium Inc., All Rights Reserved.
+ *
+ * MD5 instruction definitions added by Aaro Koskinen <aaro.koskinen@iki.fi>.
+ *
  */
 #ifndef __LINUX_OCTEON_CRYPTO_H
 #define __LINUX_OCTEON_CRYPTO_H
 
 #include <linux/sched.h>
+#include <asm/mipsregs.h>
 
 extern unsigned long octeon_crypto_enable(struct octeon_cop2_state *state);
 extern void octeon_crypto_disable(struct octeon_cop2_state *state,
 				  unsigned long flags);
 
+/*
+ * Macros needed to implement MD5:
+ */
+
+/*
+ * The index can be 0-1.
+ */
+#define write_octeon_64bit_hash_dword(value, index)	\
+do {							\
+	__asm__ __volatile__ (				\
+	"dmtc2 %[rt],0x0048+" STR(index)		\
+	:						\
+	: [rt] "d" (value));				\
+} while (0)
+
+/*
+ * The index can be 0-1.
+ */
+#define read_octeon_64bit_hash_dword(index)		\
+({							\
+	u64 __value;					\
+							\
+	__asm__ __volatile__ (				\
+	"dmfc2 %[rt],0x0048+" STR(index)		\
+	: [rt] "=d" (__value)				\
+	: );						\
+							\
+	__value;					\
+})
+
+/*
+ * The index can be 0-6.
+ */
+#define write_octeon_64bit_block_dword(value, index)	\
+do {							\
+	__asm__ __volatile__ (				\
+	"dmtc2 %[rt],0x0040+" STR(index)		\
+	:						\
+	: [rt] "d" (value));				\
+} while (0)
+
+/*
+ * The value is the final block dword (64-bit).
+ */
+#define octeon_md5_start(value)				\
+do {							\
+	__asm__ __volatile__ (				\
+	"dmtc2 %[rt],0x4047"				\
+	:						\
+	: [rt] "d" (value));				\
+} while (0)
+
 #endif /* __LINUX_OCTEON_CRYPTO_H */