xref: /openbmc/linux/arch/arm/kernel/machine_kexec.c (revision 64c70b1c)
1 /*
2  * machine_kexec.c - handle transition of Linux booting another kernel
3  */
4 
5 #include <linux/mm.h>
6 #include <linux/kexec.h>
7 #include <linux/delay.h>
8 #include <linux/reboot.h>
9 #include <asm/pgtable.h>
10 #include <asm/pgalloc.h>
11 #include <asm/mmu_context.h>
12 #include <asm/io.h>
13 #include <asm/cacheflush.h>
14 #include <asm/mach-types.h>
15 
16 const extern unsigned char relocate_new_kernel[];
17 const extern unsigned int relocate_new_kernel_size;
18 
19 extern void setup_mm_for_reboot(char mode);
20 
21 extern unsigned long kexec_start_address;
22 extern unsigned long kexec_indirection_page;
23 extern unsigned long kexec_mach_type;
24 
25 /*
26  * Provide a dummy crash_notes definition while crash dump arrives to arm.
27  * This prevents breakage of crash_notes attribute in kernel/ksysfs.c.
28  */
29 
30 int machine_kexec_prepare(struct kimage *image)
31 {
32 	return 0;
33 }
34 
35 void machine_kexec_cleanup(struct kimage *image)
36 {
37 }
38 
39 void machine_shutdown(void)
40 {
41 }
42 
43 void machine_crash_shutdown(struct pt_regs *regs)
44 {
45 }
46 
47 void machine_kexec(struct kimage *image)
48 {
49 	unsigned long page_list;
50 	unsigned long reboot_code_buffer_phys;
51 	void *reboot_code_buffer;
52 
53 
54 	page_list = image->head & PAGE_MASK;
55 
56 	/* we need both effective and real address here */
57 	reboot_code_buffer_phys =
58 	    page_to_pfn(image->control_code_page) << PAGE_SHIFT;
59 	reboot_code_buffer = page_address(image->control_code_page);
60 
61 	/* Prepare parameters for reboot_code_buffer*/
62 	kexec_start_address = image->start;
63 	kexec_indirection_page = page_list;
64 	kexec_mach_type = machine_arch_type;
65 
66 	/* copy our kernel relocation code to the control code page */
67 	memcpy(reboot_code_buffer,
68 	       relocate_new_kernel, relocate_new_kernel_size);
69 
70 
71 	flush_icache_range((unsigned long) reboot_code_buffer,
72 			   (unsigned long) reboot_code_buffer + KEXEC_CONTROL_CODE_SIZE);
73 	printk(KERN_INFO "Bye!\n");
74 
75 	cpu_proc_fin();
76 	setup_mm_for_reboot(0); /* mode is not used, so just pass 0*/
77 	cpu_reset(reboot_code_buffer_phys);
78 }
79