sparc: prepare kernel/ for unification

o sparc32 files with identical names to sparc64 renamed to <name>_32.S
o introduced a few Kconfig helpers to simplify Makefile logic
o refactored Makefile to prepare for unification
  - use obj-$(CONFIG_SPARC32) for sparc32 specific files
  - use <name>_$(BITS) for files where sparc64 has a _64 variant
  - sparc64 directly include a few files where sparc32 builds them,
    refer to these files directly (no BITS)
  - sneaked in -Werror as used by sparc64
o modified sparc/Makefile to use the new names for head/init_task

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

arch/sparc/kernel/una_asm_32.S

@@ -0,0 +1,153 @@
+/* una_asm.S: Kernel unaligned trap assembler helpers.
+ *
+ * Copyright (C) 1996,2005,2008 David S. Miller (davem@davemloft.net)
+ * Copyright (C) 1996,1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
+ */
+
+#include <linux/errno.h>
+
+	.text
+
+retl_efault:
+	retl
+	 mov	-EFAULT, %o0
+
+	/* int __do_int_store(unsigned long *dst_addr, int size,
+	 *                    unsigned long *src_val)
+	 *
+	 * %o0 = dest_addr
+	 * %o1 = size
+	 * %o2 = src_val
+	 *
+	 * Return '0' on success, -EFAULT on failure.
+	 */
+	.globl	__do_int_store
+__do_int_store:
+	ld	[%o2], %g1
+	cmp	%1, 2
+	be	2f
+	 cmp	%1, 4
+	be	1f
+	 srl	%g1, 24, %g2
+	srl	%g1, 16, %g7
+4:	stb	%g2, [%o0]
+	srl	%g1, 8, %g2
+5:	stb	%g7, [%o0 + 1]
+	ld	[%o2 + 4], %g7
+6:	stb	%g2, [%o0 + 2]
+	srl	%g7, 24, %g2
+7:	stb	%g1, [%o0 + 3]
+	srl	%g7, 16, %g1
+8:	stb	%g2, [%o0 + 4]
+	srl	%g7, 8, %g2
+9:	stb	%g1, [%o0 + 5]
+10:	stb	%g2, [%o0 + 6]
+	b	0f
+11:	 stb	%g7, [%o0 + 7]
+1:	srl	%g1, 16, %g7
+12:	stb	%g2, [%o0]
+	srl	%g1, 8, %g2
+13:	stb	%g7, [%o0 + 1]
+14:	stb	%g2, [%o0 + 2]
+	b	0f
+15:	 stb	%g1, [%o0 + 3]
+2:	srl	%g1, 8, %g2
+16:	stb	%g2, [%o0]
+17:	stb	%g1, [%o0 + 1]
+0:	retl
+	 mov	0, %o0
+
+	.section __ex_table,#alloc
+	.word	4b, retl_efault
+	.word	5b, retl_efault
+	.word	6b, retl_efault
+	.word	7b, retl_efault
+	.word	8b, retl_efault
+	.word	9b, retl_efault
+	.word	10b, retl_efault
+	.word	11b, retl_efault
+	.word	12b, retl_efault
+	.word	13b, retl_efault
+	.word	14b, retl_efault
+	.word	15b, retl_efault
+	.word	16b, retl_efault
+	.word	17b, retl_efault
+	.previous
+
+	/* int do_int_load(unsigned long *dest_reg, int size,
+	 *                 unsigned long *saddr, int is_signed)
+	 *
+	 * %o0 = dest_reg
+	 * %o1 = size
+	 * %o2 = saddr
+	 * %o3 = is_signed
+	 *
+	 * Return '0' on success, -EFAULT on failure.
+	 */
+	.globl	do_int_load
+do_int_load:
+	cmp	%o1, 8
+	be	9f
+	 cmp	%o1, 4
+	be	6f
+4:	 ldub	[%o2], %g1
+5:	ldub	[%o2 + 1], %g2
+	sll	%g1, 8, %g1
+	tst	%o3
+	be	3f
+	 or	%g1, %g2, %g1
+	sll	%g1, 16, %g1
+	sra	%g1, 16, %g1
+3:	b	0f
+	 st	%g1, [%o0]
+6:	ldub	[%o2 + 1], %g2
+	sll	%g1, 24, %g1
+7:	ldub	[%o2 + 2], %g7
+	sll	%g2, 16, %g2
+8:	ldub	[%o2 + 3], %g3
+	sll	%g7, 8, %g7
+	or	%g3, %g2, %g3
+	or	%g7, %g3, %g7
+	or	%g1, %g7, %g1
+	b	0f
+	 st	%g1, [%o0]
+9:	ldub	[%o2], %g1
+10:	ldub	[%o2 + 1], %g2
+	sll	%g1, 24, %g1
+11:	ldub	[%o2 + 2], %g7
+	sll	%g2, 16, %g2
+12:	ldub	[%o2 + 3], %g3
+	sll	%g7, 8, %g7
+	or	%g1, %g2, %g1
+	or	%g7, %g3, %g7
+	or	%g1, %g7, %g7
+13:	ldub	[%o2 + 4], %g1
+	st	%g7, [%o0]
+14:	ldub	[%o2 + 5], %g2
+	sll	%g1, 24, %g1
+15:	ldub	[%o2 + 6], %g7
+	sll	%g2, 16, %g2
+16:	ldub	[%o2 + 7], %g3
+	sll	%g7, 8, %g7
+	or	%g1, %g2, %g1
+	or	%g7, %g3, %g7
+	or	%g1, %g7, %g7
+	st	%g7, [%o0 + 4]
+0:	retl
+	 mov	0, %o0
+
+	.section __ex_table,#alloc
+	.word	4b, retl_efault
+	.word	5b, retl_efault
+	.word	6b, retl_efault
+	.word	7b, retl_efault
+	.word	8b, retl_efault
+	.word	9b, retl_efault
+	.word	10b, retl_efault
+	.word	11b, retl_efault
+	.word	12b, retl_efault
+	.word	13b, retl_efault
+	.word	14b, retl_efault
+	.word	15b, retl_efault
+	.word	16b, retl_efault
+	.previous