machine_kexec.c revision 5aafec15bdc54cf0722696c95091d7bd674bfcad 
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 <linux/io.h>
10#include <asm/pgtable.h>
11#include <asm/pgalloc.h>
12#include <asm/mmu_context.h>
13#include <asm/cacheflush.h>
14#include <asm/mach-types.h>
15
16extern const unsigned char relocate_new_kernel[];
17extern const unsigned int relocate_new_kernel_size;
18
19extern void setup_mm_for_reboot(void);
20
21extern unsigned long kexec_start_address;
22extern unsigned long kexec_indirection_page;
23extern unsigned long kexec_mach_type;
24extern unsigned long kexec_boot_atags;
25
26static atomic_t waiting_for_crash_ipi;
27
28/*
29 * Provide a dummy crash_notes definition while crash dump arrives to arm.
30 * This prevents breakage of crash_notes attribute in kernel/ksysfs.c.
31 */
32
33int machine_kexec_prepare(struct kimage *image)
34{
35	unsigned long page_list;
36	void *reboot_code_buffer;
37	page_list = image->head & PAGE_MASK;
38
39	reboot_code_buffer = page_address(image->control_code_page);
40
41	/* Prepare parameters for reboot_code_buffer*/
42	kexec_start_address = image->start;
43	kexec_indirection_page = page_list;
44	kexec_mach_type = machine_arch_type;
45	kexec_boot_atags = image->start - KEXEC_ARM_ZIMAGE_OFFSET + KEXEC_ARM_ATAGS_OFFSET;
46
47	/* copy our kernel relocation code to the control code page */
48	memcpy(reboot_code_buffer,
49	       relocate_new_kernel, relocate_new_kernel_size);
50
51	flush_icache_range((unsigned long) reboot_code_buffer,
52			   (unsigned long) reboot_code_buffer + KEXEC_CONTROL_PAGE_SIZE);
53	return 0;
54}
55
56void machine_kexec_cleanup(struct kimage *image)
57{
58}
59
60void machine_crash_nonpanic_core(void *unused)
61{
62	struct pt_regs regs;
63
64	crash_setup_regs(&regs, NULL);
65	printk(KERN_DEBUG "CPU %u will stop doing anything useful since another CPU has crashed\n",
66	       smp_processor_id());
67	crash_save_cpu(&regs, smp_processor_id());
68	flush_cache_all();
69
70	atomic_dec(&waiting_for_crash_ipi);
71	while (1)
72		cpu_relax();
73}
74
75void machine_crash_shutdown(struct pt_regs *regs)
76{
77	unsigned long msecs;
78
79	local_irq_disable();
80
81	atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
82	smp_call_function(machine_crash_nonpanic_core, NULL, false);
83	msecs = 1000; /* Wait at most a second for the other cpus to stop */
84	while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
85		mdelay(1);
86		msecs--;
87	}
88	if (atomic_read(&waiting_for_crash_ipi) > 0)
89		printk(KERN_WARNING "Non-crashing CPUs did not react to IPI\n");
90
91	crash_save_cpu(regs, smp_processor_id());
92
93	printk(KERN_INFO "Loading crashdump kernel...\n");
94}
95
96/*
97 * Function pointer to optional machine-specific reinitialization
98 */
99void (*kexec_reinit)(void);
100
101void machine_kexec(struct kimage *image)
102{
103	unsigned long reboot_code_buffer_phys;
104	void *reboot_code_buffer;
105
106	/* we need both effective and real address here */
107	reboot_code_buffer_phys =
108	    page_to_pfn(image->control_code_page) << PAGE_SHIFT;
109	reboot_code_buffer = page_address(image->control_code_page);
110
111	printk(KERN_INFO "Bye!\n");
112
113	if (kexec_reinit)
114		kexec_reinit();
115	local_irq_disable();
116	local_fiq_disable();
117	setup_mm_for_reboot();
118	flush_cache_all();
119	outer_flush_all();
120	outer_disable();
121	cpu_proc_fin();
122	outer_inv_all();
123	flush_cache_all();
124	cpu_reset(reboot_code_buffer_phys);
125}
126