xref: /openbmc/linux/arch/mips/kernel/machine_kexec.c (revision d236d361)
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 void (*_crash_smp_send_stop)(void) = NULL;
29 #endif
30 
31 static void kexec_image_info(const struct kimage *kimage)
32 {
33 	unsigned long i;
34 
35 	pr_debug("kexec kimage info:\n");
36 	pr_debug("  type:        %d\n", kimage->type);
37 	pr_debug("  start:       %lx\n", kimage->start);
38 	pr_debug("  head:        %lx\n", kimage->head);
39 	pr_debug("  nr_segments: %lu\n", kimage->nr_segments);
40 
41 	for (i = 0; i < kimage->nr_segments; i++) {
42 		pr_debug("    segment[%lu]: %016lx - %016lx, 0x%lx bytes, %lu pages\n",
43 			i,
44 			kimage->segment[i].mem,
45 			kimage->segment[i].mem + kimage->segment[i].memsz,
46 			(unsigned long)kimage->segment[i].memsz,
47 			(unsigned long)kimage->segment[i].memsz /  PAGE_SIZE);
48 	}
49 }
50 
51 int
52 machine_kexec_prepare(struct kimage *kimage)
53 {
54 	kexec_image_info(kimage);
55 
56 	if (_machine_kexec_prepare)
57 		return _machine_kexec_prepare(kimage);
58 	return 0;
59 }
60 
61 void
62 machine_kexec_cleanup(struct kimage *kimage)
63 {
64 }
65 
66 void
67 machine_shutdown(void)
68 {
69 	if (_machine_kexec_shutdown)
70 		_machine_kexec_shutdown();
71 }
72 
73 void
74 machine_crash_shutdown(struct pt_regs *regs)
75 {
76 	if (_machine_crash_shutdown)
77 		_machine_crash_shutdown(regs);
78 	else
79 		default_machine_crash_shutdown(regs);
80 }
81 
82 typedef void (*noretfun_t)(void) __noreturn;
83 
84 void
85 machine_kexec(struct kimage *image)
86 {
87 	unsigned long reboot_code_buffer;
88 	unsigned long entry;
89 	unsigned long *ptr;
90 
91 	reboot_code_buffer =
92 	  (unsigned long)page_address(image->control_code_page);
93 
94 	kexec_start_address =
95 		(unsigned long) phys_to_virt(image->start);
96 
97 	if (image->type == KEXEC_TYPE_DEFAULT) {
98 		kexec_indirection_page =
99 			(unsigned long) phys_to_virt(image->head & PAGE_MASK);
100 	} else {
101 		kexec_indirection_page = (unsigned long)&image->head;
102 	}
103 
104 	memcpy((void*)reboot_code_buffer, relocate_new_kernel,
105 	       relocate_new_kernel_size);
106 
107 	/*
108 	 * The generic kexec code builds a page list with physical
109 	 * addresses. they are directly accessible through KSEG0 (or
110 	 * CKSEG0 or XPHYS if on 64bit system), hence the
111 	 * phys_to_virt() call.
112 	 */
113 	for (ptr = &image->head; (entry = *ptr) && !(entry &IND_DONE);
114 	     ptr = (entry & IND_INDIRECTION) ?
115 	       phys_to_virt(entry & PAGE_MASK) : ptr + 1) {
116 		if (*ptr & IND_SOURCE || *ptr & IND_INDIRECTION ||
117 		    *ptr & IND_DESTINATION)
118 			*ptr = (unsigned long) phys_to_virt(*ptr);
119 	}
120 
121 	/*
122 	 * we do not want to be bothered.
123 	 */
124 	local_irq_disable();
125 
126 	printk("Will call new kernel at %08lx\n", image->start);
127 	printk("Bye ...\n");
128 	__flush_cache_all();
129 #ifdef CONFIG_SMP
130 	/* All secondary cpus now may jump to kexec_wait cycle */
131 	relocated_kexec_smp_wait = reboot_code_buffer +
132 		(void *)(kexec_smp_wait - relocate_new_kernel);
133 	smp_wmb();
134 	atomic_set(&kexec_ready_to_reboot, 1);
135 #endif
136 	((noretfun_t) reboot_code_buffer)();
137 }
138