xref: /linux/arch/sh/kernel/machine_kexec.c (revision 5499b45190237ca90dd2ac86395cf464fe1f4cc7)
1 /*
2  * machine_kexec.c - handle transition of Linux booting another kernel
3  * Copyright (C) 2002-2003 Eric Biederman  <ebiederm@xmission.com>
4  *
5  * GameCube/ppc32 port Copyright (C) 2004 Albert Herranz
6  * LANDISK/sh4 supported by kogiidena
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/mm.h>
13 #include <linux/kexec.h>
14 #include <linux/delay.h>
15 #include <linux/reboot.h>
16 #include <linux/numa.h>
17 #include <linux/ftrace.h>
18 #include <linux/suspend.h>
19 #include <asm/pgtable.h>
20 #include <asm/pgalloc.h>
21 #include <asm/mmu_context.h>
22 #include <asm/io.h>
23 #include <asm/cacheflush.h>
24 #include <asm/sh_bios.h>
25 #include <asm/reboot.h>
26 
27 typedef void (*relocate_new_kernel_t)(unsigned long indirection_page,
28 				      unsigned long reboot_code_buffer,
29 				      unsigned long start_address);
30 
31 extern const unsigned char relocate_new_kernel[];
32 extern const unsigned int relocate_new_kernel_size;
33 extern void *vbr_base;
34 
35 void native_machine_crash_shutdown(struct pt_regs *regs)
36 {
37 	/* Nothing to do for UP, but definitely broken for SMP.. */
38 }
39 
40 /*
41  * Do what every setup is needed on image and the
42  * reboot code buffer to allow us to avoid allocations
43  * later.
44  */
45 int machine_kexec_prepare(struct kimage *image)
46 {
47 	return 0;
48 }
49 
50 void machine_kexec_cleanup(struct kimage *image)
51 {
52 }
53 
54 static void kexec_info(struct kimage *image)
55 {
56         int i;
57 	printk("kexec information\n");
58 	for (i = 0; i < image->nr_segments; i++) {
59 	        printk("  segment[%d]: 0x%08x - 0x%08x (0x%08x)\n",
60 		       i,
61 		       (unsigned int)image->segment[i].mem,
62 		       (unsigned int)image->segment[i].mem +
63 				     image->segment[i].memsz,
64 		       (unsigned int)image->segment[i].memsz);
65 	}
66 	printk("  start     : 0x%08x\n\n", (unsigned int)image->start);
67 }
68 
69 /*
70  * Do not allocate memory (or fail in any way) in machine_kexec().
71  * We are past the point of no return, committed to rebooting now.
72  */
73 void machine_kexec(struct kimage *image)
74 {
75 	unsigned long page_list;
76 	unsigned long reboot_code_buffer;
77 	relocate_new_kernel_t rnk;
78 	unsigned long entry;
79 	unsigned long *ptr;
80 	int save_ftrace_enabled;
81 
82 	/*
83 	 * Nicked from the mips version of machine_kexec():
84 	 * The generic kexec code builds a page list with physical
85 	 * addresses. Use phys_to_virt() to convert them to virtual.
86 	 */
87 	for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE);
88 	     ptr = (entry & IND_INDIRECTION) ?
89 	       phys_to_virt(entry & PAGE_MASK) : ptr + 1) {
90 		if (*ptr & IND_SOURCE || *ptr & IND_INDIRECTION ||
91 		    *ptr & IND_DESTINATION)
92 			*ptr = (unsigned long) phys_to_virt(*ptr);
93 	}
94 
95 #ifdef CONFIG_KEXEC_JUMP
96 	if (image->preserve_context)
97 		save_processor_state();
98 #endif
99 
100 	save_ftrace_enabled = __ftrace_enabled_save();
101 
102 	/* Interrupts aren't acceptable while we reboot */
103 	local_irq_disable();
104 
105 	page_list = image->head;
106 
107 	/* we need both effective and real address here */
108 	reboot_code_buffer =
109 			(unsigned long)page_address(image->control_code_page);
110 
111 	/* copy our kernel relocation code to the control code page */
112 	memcpy((void *)reboot_code_buffer, relocate_new_kernel,
113 						relocate_new_kernel_size);
114 
115 	kexec_info(image);
116 	flush_cache_all();
117 
118 	sh_bios_vbr_reload();
119 
120 	/* now call it */
121 	rnk = (relocate_new_kernel_t) reboot_code_buffer;
122 	(*rnk)(page_list, reboot_code_buffer,
123 	       (unsigned long)phys_to_virt(image->start));
124 
125 #ifdef CONFIG_KEXEC_JUMP
126 	asm volatile("ldc %0, vbr" : : "r" (&vbr_base) : "memory");
127 
128 	if (image->preserve_context)
129 		restore_processor_state();
130 
131 	/* Convert page list back to physical addresses, what a mess. */
132 	for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE);
133 	     ptr = (*ptr & IND_INDIRECTION) ?
134 	       phys_to_virt(*ptr & PAGE_MASK) : ptr + 1) {
135 		if (*ptr & IND_SOURCE || *ptr & IND_INDIRECTION ||
136 		    *ptr & IND_DESTINATION)
137 			*ptr = virt_to_phys(*ptr);
138 	}
139 #endif
140 
141 	__ftrace_enabled_restore(save_ftrace_enabled);
142 }
143 
144 void arch_crash_save_vmcoreinfo(void)
145 {
146 #ifdef CONFIG_NUMA
147 	VMCOREINFO_SYMBOL(node_data);
148 	VMCOREINFO_LENGTH(node_data, MAX_NUMNODES);
149 #endif
150 }
151