blk: rq_data_dir() should not return a boolean
[cris-mirror.git] / arch / arm / kernel / machine_kexec.c
blob8bf3b7c098881b951df038575c6baf14e84df7b9
1 /*
2 * machine_kexec.c - handle transition of Linux booting another kernel
3 */
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 <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/smp_plat.h>
20 #include <asm/system_misc.h>
22 extern void relocate_new_kernel(void);
23 extern const unsigned int relocate_new_kernel_size;
25 extern unsigned long kexec_start_address;
26 extern unsigned long kexec_indirection_page;
27 extern unsigned long kexec_mach_type;
28 extern unsigned long kexec_boot_atags;
30 static atomic_t waiting_for_crash_ipi;
32 static unsigned long dt_mem;
34 * Provide a dummy crash_notes definition while crash dump arrives to arm.
35 * This prevents breakage of crash_notes attribute in kernel/ksysfs.c.
38 int machine_kexec_prepare(struct kimage *image)
40 struct kexec_segment *current_segment;
41 __be32 header;
42 int i, err;
45 * Validate that if the current HW supports SMP, then the SW supports
46 * and implements CPU hotplug for the current HW. If not, we won't be
47 * able to kexec reliably, so fail the prepare operation.
49 if (num_possible_cpus() > 1 && platform_can_secondary_boot() &&
50 !platform_can_cpu_hotplug())
51 return -EINVAL;
54 * No segment at default ATAGs address. try to locate
55 * a dtb using magic.
57 for (i = 0; i < image->nr_segments; i++) {
58 current_segment = &image->segment[i];
60 if (!memblock_is_region_memory(current_segment->mem,
61 current_segment->memsz))
62 return -EINVAL;
64 err = get_user(header, (__be32*)current_segment->buf);
65 if (err)
66 return err;
68 if (be32_to_cpu(header) == OF_DT_HEADER)
69 dt_mem = current_segment->mem;
71 return 0;
74 void machine_kexec_cleanup(struct kimage *image)
78 void machine_crash_nonpanic_core(void *unused)
80 struct pt_regs regs;
82 crash_setup_regs(&regs, NULL);
83 printk(KERN_DEBUG "CPU %u will stop doing anything useful since another CPU has crashed\n",
84 smp_processor_id());
85 crash_save_cpu(&regs, smp_processor_id());
86 flush_cache_all();
88 set_cpu_online(smp_processor_id(), false);
89 atomic_dec(&waiting_for_crash_ipi);
90 while (1)
91 cpu_relax();
94 static void machine_kexec_mask_interrupts(void)
96 unsigned int i;
97 struct irq_desc *desc;
99 for_each_irq_desc(i, desc) {
100 struct irq_chip *chip;
102 chip = irq_desc_get_chip(desc);
103 if (!chip)
104 continue;
106 if (chip->irq_eoi && irqd_irq_inprogress(&desc->irq_data))
107 chip->irq_eoi(&desc->irq_data);
109 if (chip->irq_mask)
110 chip->irq_mask(&desc->irq_data);
112 if (chip->irq_disable && !irqd_irq_disabled(&desc->irq_data))
113 chip->irq_disable(&desc->irq_data);
117 void machine_crash_shutdown(struct pt_regs *regs)
119 unsigned long msecs;
121 local_irq_disable();
123 atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
124 smp_call_function(machine_crash_nonpanic_core, NULL, false);
125 msecs = 1000; /* Wait at most a second for the other cpus to stop */
126 while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
127 mdelay(1);
128 msecs--;
130 if (atomic_read(&waiting_for_crash_ipi) > 0)
131 pr_warn("Non-crashing CPUs did not react to IPI\n");
133 crash_save_cpu(regs, smp_processor_id());
134 machine_kexec_mask_interrupts();
136 pr_info("Loading crashdump kernel...\n");
140 * Function pointer to optional machine-specific reinitialization
142 void (*kexec_reinit)(void);
144 void machine_kexec(struct kimage *image)
146 unsigned long page_list;
147 unsigned long reboot_code_buffer_phys;
148 unsigned long reboot_entry = (unsigned long)relocate_new_kernel;
149 unsigned long reboot_entry_phys;
150 void *reboot_code_buffer;
153 * This can only happen if machine_shutdown() failed to disable some
154 * CPU, and that can only happen if the checks in
155 * machine_kexec_prepare() were not correct. If this fails, we can't
156 * reliably kexec anyway, so BUG_ON is appropriate.
158 BUG_ON(num_online_cpus() > 1);
160 page_list = image->head & PAGE_MASK;
162 /* we need both effective and real address here */
163 reboot_code_buffer_phys =
164 page_to_pfn(image->control_code_page) << PAGE_SHIFT;
165 reboot_code_buffer = page_address(image->control_code_page);
167 /* Prepare parameters for reboot_code_buffer*/
168 set_kernel_text_rw();
169 kexec_start_address = image->start;
170 kexec_indirection_page = page_list;
171 kexec_mach_type = machine_arch_type;
172 kexec_boot_atags = dt_mem ?: image->start - KEXEC_ARM_ZIMAGE_OFFSET
173 + KEXEC_ARM_ATAGS_OFFSET;
175 /* copy our kernel relocation code to the control code page */
176 reboot_entry = fncpy(reboot_code_buffer,
177 reboot_entry,
178 relocate_new_kernel_size);
179 reboot_entry_phys = (unsigned long)reboot_entry +
180 (reboot_code_buffer_phys - (unsigned long)reboot_code_buffer);
182 pr_info("Bye!\n");
184 if (kexec_reinit)
185 kexec_reinit();
187 soft_restart(reboot_entry_phys);
190 void arch_crash_save_vmcoreinfo(void)
192 #ifdef CONFIG_ARM_LPAE
193 VMCOREINFO_CONFIG(ARM_LPAE);
194 #endif