xref: /linux/arch/mips/kernel/machine_kexec.c (revision 93df8a1ed6231727c5db94a80b1a6bd5ee67cec3)
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 
16 extern const unsigned char relocate_new_kernel[];
17 extern const size_t relocate_new_kernel_size;
18 
19 extern unsigned long kexec_start_address;
20 extern unsigned long kexec_indirection_page;
21 
22 int (*_machine_kexec_prepare)(struct kimage *) = NULL;
23 void (*_machine_kexec_shutdown)(void) = NULL;
24 void (*_machine_crash_shutdown)(struct pt_regs *regs) = NULL;
25 #ifdef CONFIG_SMP
26 void (*relocated_kexec_smp_wait) (void *);
27 atomic_t kexec_ready_to_reboot = ATOMIC_INIT(0);
28 #endif
29 
30 int
31 machine_kexec_prepare(struct kimage *kimage)
32 {
33 	if (_machine_kexec_prepare)
34 		return _machine_kexec_prepare(kimage);
35 	return 0;
36 }
37 
38 void
39 machine_kexec_cleanup(struct kimage *kimage)
40 {
41 }
42 
43 void
44 machine_shutdown(void)
45 {
46 	if (_machine_kexec_shutdown)
47 		_machine_kexec_shutdown();
48 }
49 
50 void
51 machine_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 
59 typedef void (*noretfun_t)(void) __noreturn;
60 
61 void
62 machine_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