machine_kexec.c revision cd0ca2ce4b2f4a5132e7e230be8a510755c20870 
1/*
2 * Code to handle transition of Linux booting another kernel.
3 *
4 * Copyright (C) 2002-2003 Eric Biederman  <ebiederm@xmission.com>
5 * GameCube/ppc32 port Copyright (C) 2004 Albert Herranz
6 * Copyright (C) 2005 IBM Corporation.
7 *
8 * This source code is licensed under the GNU General Public License,
9 * Version 2.  See the file COPYING for more details.
10 */
11
12#include <linux/kexec.h>
13#include <linux/reboot.h>
14#include <linux/threads.h>
15#include <asm/machdep.h>
16
17/*
18 * Provide a dummy crash_notes definition until crash dump is implemented.
19 * This prevents breakage of crash_notes attribute in kernel/ksysfs.c.
20 */
21note_buf_t crash_notes[NR_CPUS];
22
23void machine_crash_shutdown(struct pt_regs *regs)
24{
25	if (ppc_md.machine_crash_shutdown)
26		ppc_md.machine_crash_shutdown(regs);
27}
28
29/*
30 * Do what every setup is needed on image and the
31 * reboot code buffer to allow us to avoid allocations
32 * later.
33 */
34int machine_kexec_prepare(struct kimage *image)
35{
36	if (ppc_md.machine_kexec_prepare)
37		return ppc_md.machine_kexec_prepare(image);
38	/*
39	 * Fail if platform doesn't provide its own machine_kexec_prepare
40	 * implementation.
41	 */
42	return -ENOSYS;
43}
44
45void machine_kexec_cleanup(struct kimage *image)
46{
47	if (ppc_md.machine_kexec_cleanup)
48		ppc_md.machine_kexec_cleanup(image);
49}
50
51/*
52 * Do not allocate memory (or fail in any way) in machine_kexec().
53 * We are past the point of no return, committed to rebooting now.
54 */
55NORET_TYPE void machine_kexec(struct kimage *image)
56{
57	if (ppc_md.machine_kexec)
58		ppc_md.machine_kexec(image);
59	else {
60		/*
61		 * Fall back to normal restart if platform doesn't provide
62		 * its own kexec function, and user insist to kexec...
63		 */
64		machine_restart(NULL);
65	}
66	for(;;);
67}
68