Commit | Line | Data |
---|---|---|
c587e4a6 RP |
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> | |
fced80c7 | 9 | #include <linux/io.h> |
9141a003 | 10 | #include <linux/irq.h> |
c564df4d | 11 | #include <linux/memblock.h> |
c587e4a6 | 12 | #include <asm/pgtable.h> |
4cabd1d9 | 13 | #include <linux/of_fdt.h> |
c587e4a6 RP |
14 | #include <asm/pgalloc.h> |
15 | #include <asm/mmu_context.h> | |
c587e4a6 RP |
16 | #include <asm/cacheflush.h> |
17 | #include <asm/mach-types.h> | |
2103f6cb | 18 | #include <asm/smp_plat.h> |
9f97da78 | 19 | #include <asm/system_misc.h> |
c587e4a6 | 20 | |
e0fc4f97 TK |
21 | extern const unsigned char relocate_new_kernel[]; |
22 | extern const unsigned int relocate_new_kernel_size; | |
c587e4a6 | 23 | |
c587e4a6 RP |
24 | extern unsigned long kexec_start_address; |
25 | extern unsigned long kexec_indirection_page; | |
26 | extern unsigned long kexec_mach_type; | |
4cd9d6f7 | 27 | extern unsigned long kexec_boot_atags; |
c587e4a6 | 28 | |
b2306531 PF |
29 | static atomic_t waiting_for_crash_ipi; |
30 | ||
c587e4a6 RP |
31 | /* |
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. | |
34 | */ | |
35 | ||
36 | int machine_kexec_prepare(struct kimage *image) | |
37 | { | |
4cabd1d9 ML |
38 | struct kexec_segment *current_segment; |
39 | __be32 header; | |
40 | int i, err; | |
41 | ||
2103f6cb SW |
42 | /* |
43 | * Validate that if the current HW supports SMP, then the SW supports | |
44 | * and implements CPU hotplug for the current HW. If not, we won't be | |
45 | * able to kexec reliably, so fail the prepare operation. | |
46 | */ | |
47 | if (num_possible_cpus() > 1 && !platform_can_cpu_hotplug()) | |
48 | return -EINVAL; | |
49 | ||
4cabd1d9 ML |
50 | /* |
51 | * No segment at default ATAGs address. try to locate | |
52 | * a dtb using magic. | |
53 | */ | |
54 | for (i = 0; i < image->nr_segments; i++) { | |
55 | current_segment = &image->segment[i]; | |
56 | ||
2456f44d AK |
57 | if (!memblock_is_region_memory(current_segment->mem, |
58 | current_segment->memsz)) | |
59 | return -EINVAL; | |
c564df4d | 60 | |
4cabd1d9 ML |
61 | err = get_user(header, (__be32*)current_segment->buf); |
62 | if (err) | |
63 | return err; | |
64 | ||
65 | if (be32_to_cpu(header) == OF_DT_HEADER) | |
66 | kexec_boot_atags = current_segment->mem; | |
67 | } | |
c587e4a6 RP |
68 | return 0; |
69 | } | |
70 | ||
71 | void machine_kexec_cleanup(struct kimage *image) | |
72 | { | |
73 | } | |
74 | ||
b2306531 PF |
75 | void machine_crash_nonpanic_core(void *unused) |
76 | { | |
77 | struct pt_regs regs; | |
78 | ||
79 | crash_setup_regs(®s, NULL); | |
80 | printk(KERN_DEBUG "CPU %u will stop doing anything useful since another CPU has crashed\n", | |
81 | smp_processor_id()); | |
82 | crash_save_cpu(®s, smp_processor_id()); | |
83 | flush_cache_all(); | |
84 | ||
85 | atomic_dec(&waiting_for_crash_ipi); | |
86 | while (1) | |
87 | cpu_relax(); | |
88 | } | |
89 | ||
9141a003 WD |
90 | static void machine_kexec_mask_interrupts(void) |
91 | { | |
92 | unsigned int i; | |
93 | struct irq_desc *desc; | |
94 | ||
95 | for_each_irq_desc(i, desc) { | |
96 | struct irq_chip *chip; | |
97 | ||
98 | chip = irq_desc_get_chip(desc); | |
99 | if (!chip) | |
100 | continue; | |
101 | ||
102 | if (chip->irq_eoi && irqd_irq_inprogress(&desc->irq_data)) | |
103 | chip->irq_eoi(&desc->irq_data); | |
104 | ||
105 | if (chip->irq_mask) | |
106 | chip->irq_mask(&desc->irq_data); | |
107 | ||
108 | if (chip->irq_disable && !irqd_irq_disabled(&desc->irq_data)) | |
109 | chip->irq_disable(&desc->irq_data); | |
110 | } | |
111 | } | |
112 | ||
c587e4a6 RP |
113 | void machine_crash_shutdown(struct pt_regs *regs) |
114 | { | |
b2306531 PF |
115 | unsigned long msecs; |
116 | ||
c6383620 | 117 | local_irq_disable(); |
b2306531 PF |
118 | |
119 | atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1); | |
120 | smp_call_function(machine_crash_nonpanic_core, NULL, false); | |
121 | msecs = 1000; /* Wait at most a second for the other cpus to stop */ | |
122 | while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) { | |
123 | mdelay(1); | |
124 | msecs--; | |
125 | } | |
126 | if (atomic_read(&waiting_for_crash_ipi) > 0) | |
127 | printk(KERN_WARNING "Non-crashing CPUs did not react to IPI\n"); | |
128 | ||
c6383620 | 129 | crash_save_cpu(regs, smp_processor_id()); |
9141a003 | 130 | machine_kexec_mask_interrupts(); |
c6383620 MW |
131 | |
132 | printk(KERN_INFO "Loading crashdump kernel...\n"); | |
c587e4a6 RP |
133 | } |
134 | ||
868d172b EC |
135 | /* |
136 | * Function pointer to optional machine-specific reinitialization | |
137 | */ | |
138 | void (*kexec_reinit)(void); | |
139 | ||
c587e4a6 RP |
140 | void machine_kexec(struct kimage *image) |
141 | { | |
abf015f0 | 142 | unsigned long page_list; |
c587e4a6 RP |
143 | unsigned long reboot_code_buffer_phys; |
144 | void *reboot_code_buffer; | |
145 | ||
2103f6cb SW |
146 | /* |
147 | * This can only happen if machine_shutdown() failed to disable some | |
148 | * CPU, and that can only happen if the checks in | |
149 | * machine_kexec_prepare() were not correct. If this fails, we can't | |
150 | * reliably kexec anyway, so BUG_ON is appropriate. | |
151 | */ | |
152 | BUG_ON(num_online_cpus() > 1); | |
abf015f0 RK |
153 | |
154 | page_list = image->head & PAGE_MASK; | |
155 | ||
c587e4a6 RP |
156 | /* we need both effective and real address here */ |
157 | reboot_code_buffer_phys = | |
158 | page_to_pfn(image->control_code_page) << PAGE_SHIFT; | |
159 | reboot_code_buffer = page_address(image->control_code_page); | |
160 | ||
abf015f0 RK |
161 | /* Prepare parameters for reboot_code_buffer*/ |
162 | kexec_start_address = image->start; | |
163 | kexec_indirection_page = page_list; | |
164 | kexec_mach_type = machine_arch_type; | |
4cabd1d9 ML |
165 | if (!kexec_boot_atags) |
166 | kexec_boot_atags = image->start - KEXEC_ARM_ZIMAGE_OFFSET + KEXEC_ARM_ATAGS_OFFSET; | |
167 | ||
abf015f0 RK |
168 | |
169 | /* copy our kernel relocation code to the control code page */ | |
170 | memcpy(reboot_code_buffer, | |
171 | relocate_new_kernel, relocate_new_kernel_size); | |
172 | ||
173 | ||
174 | flush_icache_range((unsigned long) reboot_code_buffer, | |
175 | (unsigned long) reboot_code_buffer + KEXEC_CONTROL_PAGE_SIZE); | |
c587e4a6 RP |
176 | printk(KERN_INFO "Bye!\n"); |
177 | ||
868d172b EC |
178 | if (kexec_reinit) |
179 | kexec_reinit(); | |
3bdc3484 WD |
180 | |
181 | soft_restart(reboot_code_buffer_phys); | |
c587e4a6 | 182 | } |