xref: /openbmc/linux/arch/sh/kernel/machine_kexec.c (revision 3ab83521)
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 <asm/pgtable.h>
17 #include <asm/pgalloc.h>
18 #include <asm/mmu_context.h>
19 #include <asm/io.h>
20 #include <asm/cacheflush.h>
21 
22 typedef NORET_TYPE void (*relocate_new_kernel_t)(
23 				unsigned long indirection_page,
24 				unsigned long reboot_code_buffer,
25 				unsigned long start_address,
26 				unsigned long vbr_reg) ATTRIB_NORET;
27 
28 extern const unsigned char relocate_new_kernel[];
29 extern const unsigned int relocate_new_kernel_size;
30 extern void *gdb_vbr_vector;
31 
32 void machine_shutdown(void)
33 {
34 }
35 
36 void machine_crash_shutdown(struct pt_regs *regs)
37 {
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 
76 	unsigned long page_list;
77 	unsigned long reboot_code_buffer;
78 	unsigned long vbr_reg;
79 	relocate_new_kernel_t rnk;
80 
81 #if defined(CONFIG_SH_STANDARD_BIOS)
82 	vbr_reg = ((unsigned long )gdb_vbr_vector) - 0x100;
83 #else
84 	vbr_reg = 0x80000000;  // dummy
85 #endif
86 	/* Interrupts aren't acceptable while we reboot */
87 	local_irq_disable();
88 
89 	page_list = image->head;
90 
91 	/* we need both effective and real address here */
92 	reboot_code_buffer =
93 			(unsigned long)page_address(image->control_code_page);
94 
95 	/* copy our kernel relocation code to the control code page */
96 	memcpy((void *)reboot_code_buffer, relocate_new_kernel,
97 						relocate_new_kernel_size);
98 
99         kexec_info(image);
100 	flush_cache_all();
101 
102 	/* now call it */
103 	rnk = (relocate_new_kernel_t) reboot_code_buffer;
104 	(*rnk)(page_list, reboot_code_buffer, image->start, vbr_reg);
105 }
106 
107