raid: Add aarch64 NEON implementation

Change-Id: I6ad471d3b22a87bfa7e216713e04afa990a90edb
Signed-off-by: Yibo Cai <yibo.cai@arm.com>

include/multibinary_arm.h

@@ -0,0 +1,47 @@
+/* Copyright (c) 2018, Arm Limited. */
+
+/* TODO: support SVE */
+.macro mbin_dispatch name:req, func_neon:req, func_sve
+	.section .data
+	.balign 8
+	\name\()_dispatched:
+		.quad	\name\()_dispatch_init
+
+	.text
+	.global \name
+	\name\():
+		adrp	x9, \name\()_dispatched
+		ldr	x10, [x9, :lo12:\name\()_dispatched]
+		br	x10
+	\name\()_dispatch_init:
+		add	x9, x9, :lo12:\name\()_dispatched
+		adrp	x10, \func_neon
+		add	x10, x10, :lo12:\func_neon
+		str	x10, [x9]
+		br	x10
+.endm
+
+#if 0
+Macro expanded: mbin_dispatch xor_gen, xor_gen_neon
+
+.section .data
+.balign 8
+
+xor_gen_dispatched:
+	.quad	xor_gen_dispatch_init
+
+.text
+
+.global xor_gen
+xor_gen:
+	adrp	x9, xor_gen_dispatched
+	ldr	x10, [x9, :lo12:xor_gen_dispatched]
+	br	x10
+
+xor_gen_dispatch_init:
+	add	x9, x9, :lo12:xor_gen_dispatched
+	adrp	x10, xor_gen_neon
+	add	x10, x10, :lo12:xor_gen_neon
+	str	x10, [x9]
+	br	x10
+#endif