Commit | Line | Data |
---|---|---|
b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
c587e4a6 RP |
2 | /* |
3 | * machine_kexec.c - handle transition of Linux booting another kernel | |
4 | */ | |
5 | ||
6 | #include <linux/mm.h> | |
7 | #include <linux/kexec.h> | |
8 | #include <linux/delay.h> | |
9 | #include <linux/reboot.h> | |
fced80c7 | 10 | #include <linux/io.h> |
9141a003 | 11 | #include <linux/irq.h> |
c564df4d | 12 | #include <linux/memblock.h> |
4cabd1d9 | 13 | #include <linux/of_fdt.h> |
c587e4a6 | 14 | #include <asm/mmu_context.h> |
c587e4a6 | 15 | #include <asm/cacheflush.h> |
4d62e81b | 16 | #include <asm/kexec-internal.h> |
e2ccba49 | 17 | #include <asm/fncpy.h> |
c587e4a6 | 18 | #include <asm/mach-types.h> |
2103f6cb | 19 | #include <asm/smp_plat.h> |
9f97da78 | 20 | #include <asm/system_misc.h> |
74d86a70 | 21 | #include <asm/set_memory.h> |
c587e4a6 | 22 | |
e2ccba49 | 23 | extern void relocate_new_kernel(void); |
e0fc4f97 | 24 | extern const unsigned int relocate_new_kernel_size; |
c587e4a6 | 25 | |
b2306531 PF |
26 | static atomic_t waiting_for_crash_ipi; |
27 | ||
c587e4a6 RP |
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 | ||
33 | int machine_kexec_prepare(struct kimage *image) | |
34 | { | |
4cabd1d9 ML |
35 | struct kexec_segment *current_segment; |
36 | __be32 header; | |
37 | int i, err; | |
38 | ||
0d70262a RK |
39 | image->arch.kernel_r2 = image->start - KEXEC_ARM_ZIMAGE_OFFSET |
40 | + KEXEC_ARM_ATAGS_OFFSET; | |
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 | */ | |
fee3fd4f GU |
47 | if (num_possible_cpus() > 1 && platform_can_secondary_boot() && |
48 | !platform_can_cpu_hotplug()) | |
2103f6cb SW |
49 | return -EINVAL; |
50 | ||
4cabd1d9 ML |
51 | /* |
52 | * No segment at default ATAGs address. try to locate | |
53 | * a dtb using magic. | |
54 | */ | |
55 | for (i = 0; i < image->nr_segments; i++) { | |
56 | current_segment = &image->segment[i]; | |
57 | ||
0719392a | 58 | if (!memblock_is_region_memory(idmap_to_phys(current_segment->mem), |
2456f44d AK |
59 | current_segment->memsz)) |
60 | return -EINVAL; | |
c564df4d | 61 | |
4cabd1d9 ML |
62 | err = get_user(header, (__be32*)current_segment->buf); |
63 | if (err) | |
64 | return err; | |
65 | ||
0d70262a RK |
66 | if (header == cpu_to_be32(OF_DT_HEADER)) |
67 | image->arch.kernel_r2 = current_segment->mem; | |
4cabd1d9 | 68 | } |
c587e4a6 RP |
69 | return 0; |
70 | } | |
71 | ||
72 | void machine_kexec_cleanup(struct kimage *image) | |
73 | { | |
74 | } | |
75 | ||
f07c647c | 76 | static void machine_crash_nonpanic_core(void *unused) |
b2306531 PF |
77 | { |
78 | struct pt_regs regs; | |
79 | ||
8fc0b333 GP |
80 | local_fiq_disable(); |
81 | ||
1c37963b | 82 | crash_setup_regs(®s, get_irq_regs()); |
b2306531 PF |
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(®s, smp_processor_id()); | |
86 | flush_cache_all(); | |
87 | ||
4f9b4fb7 | 88 | set_cpu_online(smp_processor_id(), false); |
b2306531 | 89 | atomic_dec(&waiting_for_crash_ipi); |
5388a5b8 RK |
90 | |
91 | while (1) { | |
b2306531 | 92 | cpu_relax(); |
5388a5b8 RK |
93 | wfe(); |
94 | } | |
b2306531 PF |
95 | } |
96 | ||
8922ba71 ML |
97 | static DEFINE_PER_CPU(call_single_data_t, cpu_stop_csd) = |
98 | CSD_INIT(machine_crash_nonpanic_core, NULL); | |
99 | ||
2d7b3c64 RK |
100 | void crash_smp_send_stop(void) |
101 | { | |
102 | static int cpus_stopped; | |
103 | unsigned long msecs; | |
8922ba71 ML |
104 | call_single_data_t *csd; |
105 | int cpu, this_cpu = raw_smp_processor_id(); | |
2d7b3c64 RK |
106 | |
107 | if (cpus_stopped) | |
108 | return; | |
109 | ||
110 | atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1); | |
8922ba71 ML |
111 | for_each_online_cpu(cpu) { |
112 | if (cpu == this_cpu) | |
113 | continue; | |
114 | ||
115 | csd = &per_cpu(cpu_stop_csd, cpu); | |
116 | smp_call_function_single_async(cpu, csd); | |
117 | } | |
118 | ||
2d7b3c64 RK |
119 | msecs = 1000; /* Wait at most a second for the other cpus to stop */ |
120 | while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) { | |
121 | mdelay(1); | |
122 | msecs--; | |
123 | } | |
124 | if (atomic_read(&waiting_for_crash_ipi) > 0) | |
125 | pr_warn("Non-crashing CPUs did not react to IPI\n"); | |
126 | ||
127 | cpus_stopped = 1; | |
128 | } | |
129 | ||
9141a003 WD |
130 | static void machine_kexec_mask_interrupts(void) |
131 | { | |
132 | unsigned int i; | |
133 | struct irq_desc *desc; | |
134 | ||
135 | for_each_irq_desc(i, desc) { | |
136 | struct irq_chip *chip; | |
137 | ||
138 | chip = irq_desc_get_chip(desc); | |
139 | if (!chip) | |
140 | continue; | |
141 | ||
142 | if (chip->irq_eoi && irqd_irq_inprogress(&desc->irq_data)) | |
143 | chip->irq_eoi(&desc->irq_data); | |
144 | ||
145 | if (chip->irq_mask) | |
146 | chip->irq_mask(&desc->irq_data); | |
147 | ||
148 | if (chip->irq_disable && !irqd_irq_disabled(&desc->irq_data)) | |
149 | chip->irq_disable(&desc->irq_data); | |
150 | } | |
151 | } | |
152 | ||
c587e4a6 RP |
153 | void machine_crash_shutdown(struct pt_regs *regs) |
154 | { | |
c6383620 | 155 | local_irq_disable(); |
2d7b3c64 | 156 | crash_smp_send_stop(); |
b2306531 | 157 | |
c6383620 | 158 | crash_save_cpu(regs, smp_processor_id()); |
9141a003 | 159 | machine_kexec_mask_interrupts(); |
c6383620 | 160 | |
4ed89f22 | 161 | pr_info("Loading crashdump kernel...\n"); |
c587e4a6 RP |
162 | } |
163 | ||
164 | void machine_kexec(struct kimage *image) | |
165 | { | |
4138323e | 166 | unsigned long page_list, reboot_entry_phys; |
4d62e81b | 167 | struct kexec_relocate_data *data; |
4138323e | 168 | void (*reboot_entry)(void); |
c587e4a6 RP |
169 | void *reboot_code_buffer; |
170 | ||
2103f6cb SW |
171 | /* |
172 | * This can only happen if machine_shutdown() failed to disable some | |
173 | * CPU, and that can only happen if the checks in | |
174 | * machine_kexec_prepare() were not correct. If this fails, we can't | |
175 | * reliably kexec anyway, so BUG_ON is appropriate. | |
176 | */ | |
177 | BUG_ON(num_online_cpus() > 1); | |
abf015f0 RK |
178 | |
179 | page_list = image->head & PAGE_MASK; | |
180 | ||
c587e4a6 RP |
181 | reboot_code_buffer = page_address(image->control_code_page); |
182 | ||
abf015f0 | 183 | /* copy our kernel relocation code to the control code page */ |
e2ccba49 | 184 | reboot_entry = fncpy(reboot_code_buffer, |
4138323e | 185 | &relocate_new_kernel, |
e2ccba49 | 186 | relocate_new_kernel_size); |
4138323e | 187 | |
4d62e81b RK |
188 | data = reboot_code_buffer + relocate_new_kernel_size; |
189 | data->kexec_start_address = image->start; | |
190 | data->kexec_indirection_page = page_list; | |
191 | data->kexec_mach_type = machine_arch_type; | |
192 | data->kexec_r2 = image->arch.kernel_r2; | |
193 | ||
4138323e RK |
194 | /* get the identity mapping physical address for the reboot code */ |
195 | reboot_entry_phys = virt_to_idmap(reboot_entry); | |
abf015f0 | 196 | |
4ed89f22 | 197 | pr_info("Bye!\n"); |
c587e4a6 | 198 | |
e2ccba49 | 199 | soft_restart(reboot_entry_phys); |
c587e4a6 | 200 | } |