1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * machine_kexec.c - handle transition of Linux booting another kernel
4 * Copyright (C) 2002-2003 Eric Biederman <ebiederm@xmission.com>
5 *
6 * GameCube/ppc32 port Copyright (C) 2004 Albert Herranz
7 * LANDISK/sh4 supported by kogiidena
8 */
9 #include <linux/mm.h>
10 #include <linux/kexec.h>
11 #include <linux/delay.h>
12 #include <linux/reboot.h>
13 #include <linux/numa.h>
14 #include <linux/ftrace.h>
15 #include <linux/suspend.h>
16 #include <linux/memblock.h>
17 #include <asm/mmu_context.h>
18 #include <asm/io.h>
19 #include <asm/cacheflush.h>
20 #include <asm/sh_bios.h>
21 #include <asm/reboot.h>
22
23 typedef void (*relocate_new_kernel_t)(unsigned long indirection_page,
24 unsigned long reboot_code_buffer,
25 unsigned long start_address);
26
27 extern const unsigned char relocate_new_kernel[];
28 extern const unsigned int relocate_new_kernel_size;
29 extern void *vbr_base;
30
31 void native_machine_crash_shutdown(struct pt_regs *regs)
32 {
33 /* Nothing to do for UP, but definitely broken for SMP.. */
34 }
35
36 /*
37 * Do what every setup is needed on image and the
38 * reboot code buffer to allow us to avoid allocations
39 * later.
40 */
41 int machine_kexec_prepare(struct kimage *image)
42 {
43 return 0;
44 }
45
46 void machine_kexec_cleanup(struct kimage *image)
47 {
48 }
49
50 static void kexec_info(struct kimage *image)
51 {
52 int i;
53 printk("kexec information\n");
54 for (i = 0; i < image->nr_segments; i++) {
55 printk(" segment[%d]: 0x%08x - 0x%08x (0x%08x)\n",
56 i,
57 (unsigned int)image->segment[i].mem,
58 (unsigned int)image->segment[i].mem +
59 image->segment[i].memsz,
60 (unsigned int)image->segment[i].memsz);
61 }
62 printk(" start : 0x%08x\n\n", (unsigned int)image->start);
63 }
64
65 /*
66 * Do not allocate memory (or fail in any way) in machine_kexec().
67 * We are past the point of no return, committed to rebooting now.
68 */
69 void machine_kexec(struct kimage *image)
70 {
71 unsigned long page_list;
72 unsigned long reboot_code_buffer;
73 relocate_new_kernel_t rnk;
74 unsigned long entry;
75 unsigned long *ptr;
76 int save_ftrace_enabled;
77
78 /*
79 * Nicked from the mips version of machine_kexec():
80 * The generic kexec code builds a page list with physical
81 * addresses. Use phys_to_virt() to convert them to virtual.
82 */
83 for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE);
84 ptr = (entry & IND_INDIRECTION) ?
85 phys_to_virt(entry & PAGE_MASK) : ptr + 1) {
86 if (*ptr & IND_SOURCE || *ptr & IND_INDIRECTION ||
87 *ptr & IND_DESTINATION)
88 *ptr = (unsigned long) phys_to_virt(*ptr);
89 }
90
91 #ifdef CONFIG_KEXEC_JUMP
92 if (image->preserve_context)
93 save_processor_state();
94 #endif
95
96 save_ftrace_enabled = __ftrace_enabled_save();
97
98 /* Interrupts aren't acceptable while we reboot */
99 local_irq_disable();
100
101 page_list = image->head;
102
103 /* we need both effective and real address here */
104 reboot_code_buffer =
105 (unsigned long)page_address(image->control_code_page);
106
107 /* copy our kernel relocation code to the control code page */
108 memcpy((void *)reboot_code_buffer, relocate_new_kernel,
109 relocate_new_kernel_size);
110
111 kexec_info(image);
112 flush_cache_all();
113
114 sh_bios_vbr_reload();
115
116 /* now call it */
117 rnk = (relocate_new_kernel_t) reboot_code_buffer;
118 (*rnk)(page_list, reboot_code_buffer,
119 (unsigned long)phys_to_virt(image->start));
120
121 #ifdef CONFIG_KEXEC_JUMP
122 asm volatile("ldc %0, vbr" : : "r" (&vbr_base) : "memory");
123
124 if (image->preserve_context)
125 restore_processor_state();
126
127 /* Convert page list back to physical addresses, what a mess. */
128 for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE);
129 ptr = (*ptr & IND_INDIRECTION) ?
130 phys_to_virt(*ptr & PAGE_MASK) : ptr + 1) {
131 if (*ptr & IND_SOURCE || *ptr & IND_INDIRECTION ||
132 *ptr & IND_DESTINATION)
133 *ptr = virt_to_phys(*ptr);
134 }
135 #endif
136
137 __ftrace_enabled_restore(save_ftrace_enabled);
138 }
139
140 void __init reserve_crashkernel(void)
141 {
142 unsigned long long crash_size, crash_base;
143 int ret;
144
145 if (!IS_ENABLED(CONFIG_CRASH_RESERVE))
146 return;
147
148 ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(),
149 &crash_size, &crash_base, NULL, NULL);
150 if (ret == 0 && crash_size > 0) {
151 crashk_res.start = crash_base;
152 crashk_res.end = crash_base + crash_size - 1;
153 }
154
155 if (crashk_res.end == crashk_res.start)
156 goto disable;
157
158 crash_size = PAGE_ALIGN(resource_size(&crashk_res));
159 if (!crashk_res.start) {
160 unsigned long max = memblock_end_of_DRAM() - memory_limit;
161 crashk_res.start = memblock_phys_alloc_range(crash_size,
162 PAGE_SIZE, 0, max);
163 if (!crashk_res.start) {
164 pr_err("crashkernel allocation failed\n");
165 goto disable;
166 }
167 } else {
168 ret = memblock_reserve(crashk_res.start, crash_size);
169 if (unlikely(ret < 0)) {
170 pr_err("crashkernel reservation failed - "
171 "memory is in use\n");
172 goto disable;
173 }
174 }
175
176 crashk_res.end = crashk_res.start + crash_size - 1;
177
178 /*
179 * Crash kernel trumps memory limit
180 */
181 if ((memblock_end_of_DRAM() - memory_limit) <= crashk_res.end) {
182 memory_limit = 0;
183 pr_info("Disabled memory limit for crashkernel\n");
184 }
185
186 pr_info("Reserving %ldMB of memory at 0x%08lx "
187 "for crashkernel (System RAM: %ldMB)\n",
188 (unsigned long)(crash_size >> 20),
189 (unsigned long)(crashk_res.start),
190 (unsigned long)(memblock_phys_mem_size() >> 20));
191
192 return;
193
194 disable:
195 crashk_res.start = crashk_res.end = 0;
196 }
197
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