2 * machine_kexec.c - handle transition of Linux booting another kernel
6 #include <linux/kexec.h>
7 #include <linux/delay.h>
8 #include <linux/reboot.h>
10 #include <linux/irq.h>
11 #include <linux/memblock.h>
12 #include <asm/pgtable.h>
13 #include <linux/of_fdt.h>
14 #include <asm/pgalloc.h>
15 #include <asm/mmu_context.h>
16 #include <asm/cacheflush.h>
17 #include <asm/mach-types.h>
18 #include <asm/system_misc.h>
20 extern const unsigned char relocate_new_kernel[];
21 extern const unsigned int relocate_new_kernel_size;
23 extern unsigned long kexec_start_address;
24 extern unsigned long kexec_indirection_page;
25 extern unsigned long kexec_mach_type;
26 extern unsigned long kexec_boot_atags;
28 static atomic_t waiting_for_crash_ipi;
31 * Provide a dummy crash_notes definition while crash dump arrives to arm.
32 * This prevents breakage of crash_notes attribute in kernel/ksysfs.c.
35 int machine_kexec_prepare(struct kimage *image)
37 struct kexec_segment *current_segment;
42 * No segment at default ATAGs address. try to locate
45 for (i = 0; i < image->nr_segments; i++) {
46 current_segment = &image->segment[i];
48 if (!memblock_is_region_memory(current_segment->mem,
49 current_segment->memsz))
52 err = get_user(header, (__be32*)current_segment->buf);
56 if (be32_to_cpu(header) == OF_DT_HEADER)
57 kexec_boot_atags = current_segment->mem;
62 void machine_kexec_cleanup(struct kimage *image)
66 void machine_crash_nonpanic_core(void *unused)
70 crash_setup_regs(®s, NULL);
71 printk(KERN_DEBUG "CPU %u will stop doing anything useful since another CPU has crashed\n",
73 crash_save_cpu(®s, smp_processor_id());
76 set_cpu_online(smp_processor_id(), false);
77 atomic_dec(&waiting_for_crash_ipi);
82 static void machine_kexec_mask_interrupts(void)
85 struct irq_desc *desc;
87 for_each_irq_desc(i, desc) {
88 struct irq_chip *chip;
90 chip = irq_desc_get_chip(desc);
94 if (chip->irq_eoi && irqd_irq_inprogress(&desc->irq_data))
95 chip->irq_eoi(&desc->irq_data);
98 chip->irq_mask(&desc->irq_data);
100 if (chip->irq_disable && !irqd_irq_disabled(&desc->irq_data))
101 chip->irq_disable(&desc->irq_data);
105 void machine_crash_shutdown(struct pt_regs *regs)
111 atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
112 smp_call_function(machine_crash_nonpanic_core, NULL, false);
113 msecs = 1000; /* Wait at most a second for the other cpus to stop */
114 while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
118 if (atomic_read(&waiting_for_crash_ipi) > 0)
119 printk(KERN_WARNING "Non-crashing CPUs did not react to IPI\n");
121 crash_save_cpu(regs, smp_processor_id());
122 machine_kexec_mask_interrupts();
124 printk(KERN_INFO "Loading crashdump kernel...\n");
128 * Function pointer to optional machine-specific reinitialization
130 void (*kexec_reinit)(void);
132 void machine_kexec(struct kimage *image)
134 unsigned long page_list;
135 unsigned long reboot_code_buffer_phys;
136 void *reboot_code_buffer;
138 if (num_online_cpus() > 1) {
139 pr_err("kexec: error: multiple CPUs still online\n");
143 page_list = image->head & PAGE_MASK;
145 /* we need both effective and real address here */
146 reboot_code_buffer_phys =
147 page_to_pfn(image->control_code_page) << PAGE_SHIFT;
148 reboot_code_buffer = page_address(image->control_code_page);
150 /* Prepare parameters for reboot_code_buffer*/
151 kexec_start_address = image->start;
152 kexec_indirection_page = page_list;
153 kexec_mach_type = machine_arch_type;
154 if (!kexec_boot_atags)
155 kexec_boot_atags = image->start - KEXEC_ARM_ZIMAGE_OFFSET + KEXEC_ARM_ATAGS_OFFSET;
158 /* copy our kernel relocation code to the control code page */
159 memcpy(reboot_code_buffer,
160 relocate_new_kernel, relocate_new_kernel_size);
163 flush_icache_range((unsigned long) reboot_code_buffer,
164 (unsigned long) reboot_code_buffer + KEXEC_CONTROL_PAGE_SIZE);
165 printk(KERN_INFO "Bye!\n");
170 soft_restart(reboot_code_buffer_phys);