sh2(A) exception handler update

This patch is

By sh2
- Remove duplicate code
- Reduce stack usage
- Cleanup and little optimize

By sh2a
- Add missing handler(256 to 511)
- Use sh2a instructions handler

Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

arch/sh/kernel/cpu/sh2/ex.S

@@ -18,16 +18,17 @@
 exception_entry:	
 no	=	0
 	.rept	256
-	mov.l	r0,@-sp
-	mov	#no,r0
+	mov.l	r1,@-sp
 	bra	exception_trampoline
-	and	#0xff,r0
+	mov	#no,r1
 no	=	no + 1
 	.endr
 exception_trampoline:
-	mov.l	r1,@-sp
-	mov.l	$exception_handler,r1
-	jmp	@r1
+	mov.l	r0,@-sp
+	mov.l	$exception_handler,r0
+	extu.b	r1,r1
+	jmp	@r0
+	  extu.w	r1,r1
 
 	.align	2
 $exception_entry:
@@ -41,6 +42,6 @@ $exception_handler:
 ENTRY(vbr_base)
 vector	=	0
 	.rept	256
-	.long	exception_entry + vector * 8
+	.long	exception_entry + vector * 6
 vector	=	vector + 1
 	.endr