[PATCH] sh: kexec() support

This adds kexec() support for SH.

Signed-off-by: kogiidena <kogiidena@eggplant.ddo.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Cc: <fastboot@lists.osdl.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/sh/kernel/relocate_kernel.S

@@ -0,0 +1,102 @@
+/*
+ * relocate_kernel.S - put the kernel image in place to boot
+ * 2005.9.17 kogiidena@eggplant.ddo.jp
+ *
+ * LANDISK/sh4 is supported. Maybe, SH archtecture works well.
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2.  See the file COPYING for more details.
+ */
+
+#include <linux/config.h>
+#include <linux/linkage.h>
+
+#define PAGE_SIZE      4096 /* must be same value as in <asm/page.h> */
+
+
+		.globl relocate_new_kernel
+relocate_new_kernel:
+	/* r4 = indirection_page   */
+	/* r5 = reboot_code_buffer */
+	/* r6 = start_address      */
+	/* r7 = vbr_reg            */
+
+	mov.l	10f,r8	  /* 4096 */
+	mov.l	11f,r9    /* 0xa0000000 */
+
+	/*  stack setting */
+	add	r8,r5
+	mov	r5,r15
+
+	bra	1f
+	mov	r4,r0	  /* cmd = indirection_page */
+0:
+	mov.l	@r4+,r0	  /* cmd = *ind++ */
+
+1:	/* addr = (cmd | 0xa0000000) & 0xfffffff0 */
+	mov	r0,r2
+	or	r9,r2
+	mov	#-16,r1
+	and	r1,r2
+
+	/* if(cmd & IND_DESTINATION) dst = addr  */
+	tst	#1,r0
+	bt	2f
+	bra	0b
+	mov	r2,r5
+
+2:	/* else if(cmd & IND_INDIRECTION) ind = addr  */
+	tst	#2,r0
+	bt	3f
+	bra	0b
+	mov	r2,r4
+
+3:	/* else if(cmd & IND_DONE) goto 6  */
+	tst	#4,r0
+	bt	4f
+	bra	6f
+	nop
+
+4:	/* else if(cmd & IND_SOURCE) memcpy(dst,addr,PAGE_SIZE) */
+	tst	#8,r0
+	bt	0b
+
+	mov	r8,r3
+	shlr2	r3
+	shlr2	r3
+5:
+	dt	r3
+	mov.l	@r2+,r1   /*  16n+0 */
+	mov.l	r1,@r5
+	add	#4,r5
+	mov.l	@r2+,r1	  /*  16n+4 */
+	mov.l	r1,@r5
+	add	#4,r5
+	mov.l	@r2+,r1   /*  16n+8 */
+	mov.l	r1,@r5
+	add	#4,r5
+	mov.l	@r2+,r1   /*  16n+12 */
+	mov.l	r1,@r5
+	add	#4,r5
+	bf	5b
+
+	bra	0b
+	nop
+6:
+#ifdef CONFIG_SH_STANDARD_BIOS
+	ldc   r7, vbr
+#endif
+	jmp @r6
+	nop
+
+	.align 2
+10:
+	.long	PAGE_SIZE
+11:
+	.long	0xa0000000
+
+relocate_new_kernel_end:
+
+	.globl relocate_new_kernel_size
+relocate_new_kernel_size:
+	.long relocate_new_kernel_end - relocate_new_kernel