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/fncpy.h>
18 #include <asm/mach-types.h>
19 #include <asm/system_misc.h>
21 extern void relocate_new_kernel(void);
22 extern const unsigned int relocate_new_kernel_size;
24 extern unsigned long kexec_start_address;
25 extern unsigned long kexec_indirection_page;
26 extern unsigned long kexec_mach_type;
27 extern unsigned long kexec_boot_atags;
29 static atomic_t waiting_for_crash_ipi;
32 * Provide a dummy crash_notes definition while crash dump arrives to arm.
33 * This prevents breakage of crash_notes attribute in kernel/ksysfs.c.
36 int machine_kexec_prepare(struct kimage *image)
38 struct kexec_segment *current_segment;
43 * No segment at default ATAGs address. try to locate
46 for (i = 0; i < image->nr_segments; i++) {
47 current_segment = &image->segment[i];
49 if (!memblock_is_region_memory(current_segment->mem,
50 current_segment->memsz))
53 err = get_user(header, (__be32*)current_segment->buf);
57 if (be32_to_cpu(header) == OF_DT_HEADER)
58 kexec_boot_atags = current_segment->mem;
63 void machine_kexec_cleanup(struct kimage *image)
67 void machine_crash_nonpanic_core(void *unused)
71 crash_setup_regs(®s, NULL);
72 printk(KERN_DEBUG "CPU %u will stop doing anything useful since another CPU has crashed\n",
74 crash_save_cpu(®s, smp_processor_id());
77 set_cpu_online(smp_processor_id(), false);
78 atomic_dec(&waiting_for_crash_ipi);
83 static void machine_kexec_mask_interrupts(void)
86 struct irq_desc *desc;
88 for_each_irq_desc(i, desc) {
89 struct irq_chip *chip;
91 chip = irq_desc_get_chip(desc);
95 if (chip->irq_eoi && irqd_irq_inprogress(&desc->irq_data))
96 chip->irq_eoi(&desc->irq_data);
99 chip->irq_mask(&desc->irq_data);
101 if (chip->irq_disable && !irqd_irq_disabled(&desc->irq_data))
102 chip->irq_disable(&desc->irq_data);
106 void machine_crash_shutdown(struct pt_regs *regs)
112 atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
113 smp_call_function(machine_crash_nonpanic_core, NULL, false);
114 msecs = 1000; /* Wait at most a second for the other cpus to stop */
115 while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
119 if (atomic_read(&waiting_for_crash_ipi) > 0)
120 printk(KERN_WARNING "Non-crashing CPUs did not react to IPI\n");
122 crash_save_cpu(regs, smp_processor_id());
123 machine_kexec_mask_interrupts();
125 printk(KERN_INFO "Loading crashdump kernel...\n");
129 * Function pointer to optional machine-specific reinitialization
131 void (*kexec_reinit)(void);
133 void machine_kexec(struct kimage *image)
135 unsigned long page_list;
136 unsigned long reboot_code_buffer_phys;
137 unsigned long reboot_entry = (unsigned long)relocate_new_kernel;
138 unsigned long reboot_entry_phys;
139 void *reboot_code_buffer;
141 if (num_online_cpus() > 1) {
142 pr_err("kexec: error: multiple CPUs still online\n");
146 page_list = image->head & PAGE_MASK;
148 /* we need both effective and real address here */
149 reboot_code_buffer_phys =
150 page_to_pfn(image->control_code_page) << PAGE_SHIFT;
151 reboot_code_buffer = page_address(image->control_code_page);
153 /* Prepare parameters for reboot_code_buffer*/
154 kexec_start_address = image->start;
155 kexec_indirection_page = page_list;
156 kexec_mach_type = machine_arch_type;
157 if (!kexec_boot_atags)
158 kexec_boot_atags = image->start - KEXEC_ARM_ZIMAGE_OFFSET + KEXEC_ARM_ATAGS_OFFSET;
161 /* copy our kernel relocation code to the control code page */
162 reboot_entry = fncpy(reboot_code_buffer,
164 relocate_new_kernel_size);
165 reboot_entry_phys = (unsigned long)reboot_entry +
166 (reboot_code_buffer_phys - (unsigned long)reboot_code_buffer);
168 printk(KERN_INFO "Bye!\n");
173 soft_restart(reboot_entry_phys);
176 void arch_crash_save_vmcoreinfo(void)
178 #ifdef CONFIG_ARM_LPAE
179 VMCOREINFO_CONFIG(ARM_LPAE);