[SPARC64]: Do not assume sun4v chips have load-twin/store-init support.

Check the cpu type in the OBP device tree before committing to
using the optimized Niagara memcpy and memset implementation.

If we don't recognize the cpu type, use a completely generic
version.

Signed-off-by: David S. Miller <davem@davemloft.net>

arch/sparc64/lib/GENcopy_from_user.S

@@ -0,0 +1,34 @@
+/* GENcopy_from_user.S: Generic sparc64 copy from userspace.
+ *
+ * Copyright (C) 2007 David S. Miller (davem@davemloft.net)
+ */
+
+#define EX_LD(x)		\
+98:	x;			\
+	.section .fixup;	\
+	.align 4;		\
+99:	retl;			\
+	 mov	1, %o0;		\
+	.section __ex_table,"a";\
+	.align 4;		\
+	.word 98b, 99b;		\
+	.text;			\
+	.align 4;
+
+#ifndef ASI_AIUS
+#define ASI_AIUS	0x11
+#endif
+
+#define FUNC_NAME		GENcopy_from_user
+#define LOAD(type,addr,dest)	type##a [addr] ASI_AIUS, dest
+#define EX_RETVAL(x)		0
+
+#ifdef __KERNEL__
+#define PREAMBLE					\
+	rd		%asi, %g1;			\
+	cmp		%g1, ASI_AIUS;			\
+	bne,pn		%icc, memcpy_user_stub;		\
+	 nop
+#endif
+
+#include "GENmemcpy.S"