xref: /openbmc/linux/arch/s390/kernel/machine_kexec.c (revision 4800cd83)
1 /*
2  * arch/s390/kernel/machine_kexec.c
3  *
4  * Copyright IBM Corp. 2005,2006
5  *
6  * Author(s): Rolf Adelsberger,
7  *	      Heiko Carstens <heiko.carstens@de.ibm.com>
8  */
9 
10 #include <linux/device.h>
11 #include <linux/mm.h>
12 #include <linux/kexec.h>
13 #include <linux/delay.h>
14 #include <linux/reboot.h>
15 #include <asm/cio.h>
16 #include <asm/setup.h>
17 #include <asm/pgtable.h>
18 #include <asm/pgalloc.h>
19 #include <asm/system.h>
20 #include <asm/smp.h>
21 #include <asm/reset.h>
22 #include <asm/ipl.h>
23 
24 typedef void (*relocate_kernel_t)(kimage_entry_t *, unsigned long);
25 
26 extern const unsigned char relocate_kernel[];
27 extern const unsigned long long relocate_kernel_len;
28 
29 int machine_kexec_prepare(struct kimage *image)
30 {
31 	void *reboot_code_buffer;
32 
33 	/* Can't replace kernel image since it is read-only. */
34 	if (ipl_flags & IPL_NSS_VALID)
35 		return -ENOSYS;
36 
37 	/* We don't support anything but the default image type for now. */
38 	if (image->type != KEXEC_TYPE_DEFAULT)
39 		return -EINVAL;
40 
41 	/* Get the destination where the assembler code should be copied to.*/
42 	reboot_code_buffer = (void *) page_to_phys(image->control_code_page);
43 
44 	/* Then copy it */
45 	memcpy(reboot_code_buffer, relocate_kernel, relocate_kernel_len);
46 	return 0;
47 }
48 
49 void machine_kexec_cleanup(struct kimage *image)
50 {
51 }
52 
53 void machine_shutdown(void)
54 {
55 }
56 
57 static void __machine_kexec(void *data)
58 {
59 	relocate_kernel_t data_mover;
60 	struct kimage *image = data;
61 
62 	pfault_fini();
63 	s390_reset_system();
64 
65 	data_mover = (relocate_kernel_t) page_to_phys(image->control_code_page);
66 
67 	/* Call the moving routine */
68 	(*data_mover)(&image->head, image->start);
69 	for (;;);
70 }
71 
72 void machine_kexec(struct kimage *image)
73 {
74 	smp_send_stop();
75 	smp_switch_to_ipl_cpu(__machine_kexec, image);
76 }
77