1/*
2 * machine_kexec.c for kexec
3 * Created by <nschichan@corp.free.fr> on Thu Oct 12 15:15:06 2006
4 *
5 * This source code is licensed under the GNU General Public License,
6 * Version 2.  See the file COPYING for more details.
7 */
8#include <linux/compiler.h>
9#include <linux/kexec.h>
10#include <linux/mm.h>
11#include <linux/delay.h>
12
13#include <asm/cacheflush.h>
14#include <asm/page.h>
15
16extern const unsigned char relocate_new_kernel[];
17extern const size_t relocate_new_kernel_size;
18
19extern unsigned long kexec_start_address;
20extern unsigned long kexec_indirection_page;
21
22int (*_machine_kexec_prepare)(struct kimage *) = NULL;
23void (*_machine_kexec_shutdown)(void) = NULL;
24void (*_machine_crash_shutdown)(struct pt_regs *regs) = NULL;
25#ifdef CONFIG_SMP
26void (*relocated_kexec_smp_wait) (void *);
27atomic_t kexec_ready_to_reboot = ATOMIC_INIT(0);
28#endif
29
30int
31machine_kexec_prepare(struct kimage *kimage)
32{
33	if (_machine_kexec_prepare)
34		return _machine_kexec_prepare(kimage);
35	return 0;
36}
37
38void
39machine_kexec_cleanup(struct kimage *kimage)
40{
41}
42
43void
44machine_shutdown(void)
45{
46	if (_machine_kexec_shutdown)
47		_machine_kexec_shutdown();
48}
49
50void
51machine_crash_shutdown(struct pt_regs *regs)
52{
53	if (_machine_crash_shutdown)
54		_machine_crash_shutdown(regs);
55	else
56		default_machine_crash_shutdown(regs);
57}
58
59typedef void (*noretfun_t)(void) __noreturn;
60
61void
62machine_kexec(struct kimage *image)
63{
64	unsigned long reboot_code_buffer;
65	unsigned long entry;
66	unsigned long *ptr;
67
68	reboot_code_buffer =
69	  (unsigned long)page_address(image->control_code_page);
70
71	kexec_start_address =
72		(unsigned long) phys_to_virt(image->start);
73
74	if (image->type == KEXEC_TYPE_DEFAULT) {
75		kexec_indirection_page =
76			(unsigned long) phys_to_virt(image->head & PAGE_MASK);
77	} else {
78		kexec_indirection_page = (unsigned long)&image->head;
79	}
80
81	memcpy((void*)reboot_code_buffer, relocate_new_kernel,
82	       relocate_new_kernel_size);
83
84	/*
85	 * The generic kexec code builds a page list with physical
86	 * addresses. they are directly accessible through KSEG0 (or
87	 * CKSEG0 or XPHYS if on 64bit system), hence the
88	 * phys_to_virt() call.
89	 */
90	for (ptr = &image->head; (entry = *ptr) && !(entry &IND_DONE);
91	     ptr = (entry & IND_INDIRECTION) ?
92	       phys_to_virt(entry & PAGE_MASK) : ptr + 1) {
93		if (*ptr & IND_SOURCE || *ptr & IND_INDIRECTION ||
94		    *ptr & IND_DESTINATION)
95			*ptr = (unsigned long) phys_to_virt(*ptr);
96	}
97
98	/*
99	 * we do not want to be bothered.
100	 */
101	local_irq_disable();
102
103	printk("Will call new kernel at %08lx\n", image->start);
104	printk("Bye ...\n");
105	__flush_cache_all();
106#ifdef CONFIG_SMP
107	/* All secondary cpus now may jump to kexec_wait cycle */
108	relocated_kexec_smp_wait = reboot_code_buffer +
109		(void *)(kexec_smp_wait - relocate_new_kernel);
110	smp_wmb();
111	atomic_set(&kexec_ready_to_reboot, 1);
112#endif
113	((noretfun_t) reboot_code_buffer)();
114}
115