xref: /openbmc/linux/arch/sh/kernel/machine_kexec.c (revision b8265621)
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/pgalloc.h>
18 #include <asm/mmu_context.h>
19 #include <asm/io.h>
20 #include <asm/cacheflush.h>
21 #include <asm/sh_bios.h>
22 #include <asm/reboot.h>
23 
24 typedef void (*relocate_new_kernel_t)(unsigned long indirection_page,
25 				      unsigned long reboot_code_buffer,
26 				      unsigned long start_address);
27 
28 extern const unsigned char relocate_new_kernel[];
29 extern const unsigned int relocate_new_kernel_size;
30 extern void *vbr_base;
31 
32 void native_machine_crash_shutdown(struct pt_regs *regs)
33 {
34 	/* Nothing to do for UP, but definitely broken for SMP.. */
35 }
36 
37 /*
38  * Do what every setup is needed on image and the
39  * reboot code buffer to allow us to avoid allocations
40  * later.
41  */
42 int machine_kexec_prepare(struct kimage *image)
43 {
44 	return 0;
45 }
46 
47 void machine_kexec_cleanup(struct kimage *image)
48 {
49 }
50 
51 static void kexec_info(struct kimage *image)
52 {
53         int i;
54 	printk("kexec information\n");
55 	for (i = 0; i < image->nr_segments; i++) {
56 	        printk("  segment[%d]: 0x%08x - 0x%08x (0x%08x)\n",
57 		       i,
58 		       (unsigned int)image->segment[i].mem,
59 		       (unsigned int)image->segment[i].mem +
60 				     image->segment[i].memsz,
61 		       (unsigned int)image->segment[i].memsz);
62 	}
63 	printk("  start     : 0x%08x\n\n", (unsigned int)image->start);
64 }
65 
66 /*
67  * Do not allocate memory (or fail in any way) in machine_kexec().
68  * We are past the point of no return, committed to rebooting now.
69  */
70 void machine_kexec(struct kimage *image)
71 {
72 	unsigned long page_list;
73 	unsigned long reboot_code_buffer;
74 	relocate_new_kernel_t rnk;
75 	unsigned long entry;
76 	unsigned long *ptr;
77 	int save_ftrace_enabled;
78 
79 	/*
80 	 * Nicked from the mips version of machine_kexec():
81 	 * The generic kexec code builds a page list with physical
82 	 * addresses. Use phys_to_virt() to convert them to virtual.
83 	 */
84 	for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE);
85 	     ptr = (entry & IND_INDIRECTION) ?
86 	       phys_to_virt(entry & PAGE_MASK) : ptr + 1) {
87 		if (*ptr & IND_SOURCE || *ptr & IND_INDIRECTION ||
88 		    *ptr & IND_DESTINATION)
89 			*ptr = (unsigned long) phys_to_virt(*ptr);
90 	}
91 
92 #ifdef CONFIG_KEXEC_JUMP
93 	if (image->preserve_context)
94 		save_processor_state();
95 #endif
96 
97 	save_ftrace_enabled = __ftrace_enabled_save();
98 
99 	/* Interrupts aren't acceptable while we reboot */
100 	local_irq_disable();
101 
102 	page_list = image->head;
103 
104 	/* we need both effective and real address here */
105 	reboot_code_buffer =
106 			(unsigned long)page_address(image->control_code_page);
107 
108 	/* copy our kernel relocation code to the control code page */
109 	memcpy((void *)reboot_code_buffer, relocate_new_kernel,
110 						relocate_new_kernel_size);
111 
112 	kexec_info(image);
113 	flush_cache_all();
114 
115 	sh_bios_vbr_reload();
116 
117 	/* now call it */
118 	rnk = (relocate_new_kernel_t) reboot_code_buffer;
119 	(*rnk)(page_list, reboot_code_buffer,
120 	       (unsigned long)phys_to_virt(image->start));
121 
122 #ifdef CONFIG_KEXEC_JUMP
123 	asm volatile("ldc %0, vbr" : : "r" (&vbr_base) : "memory");
124 
125 	if (image->preserve_context)
126 		restore_processor_state();
127 
128 	/* Convert page list back to physical addresses, what a mess. */
129 	for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE);
130 	     ptr = (*ptr & IND_INDIRECTION) ?
131 	       phys_to_virt(*ptr & PAGE_MASK) : ptr + 1) {
132 		if (*ptr & IND_SOURCE || *ptr & IND_INDIRECTION ||
133 		    *ptr & IND_DESTINATION)
134 			*ptr = virt_to_phys(*ptr);
135 	}
136 #endif
137 
138 	__ftrace_enabled_restore(save_ftrace_enabled);
139 }
140 
141 void arch_crash_save_vmcoreinfo(void)
142 {
143 #ifdef CONFIG_NUMA
144 	VMCOREINFO_SYMBOL(node_data);
145 	VMCOREINFO_LENGTH(node_data, MAX_NUMNODES);
146 #endif
147 #ifdef CONFIG_X2TLB
148 	VMCOREINFO_CONFIG(X2TLB);
149 #endif
150 }
151 
152 void __init reserve_crashkernel(void)
153 {
154 	unsigned long long crash_size, crash_base;
155 	int ret;
156 
157 	ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(),
158 			&crash_size, &crash_base);
159 	if (ret == 0 && crash_size > 0) {
160 		crashk_res.start = crash_base;
161 		crashk_res.end = crash_base + crash_size - 1;
162 	}
163 
164 	if (crashk_res.end == crashk_res.start)
165 		goto disable;
166 
167 	crash_size = PAGE_ALIGN(resource_size(&crashk_res));
168 	if (!crashk_res.start) {
169 		unsigned long max = memblock_end_of_DRAM() - memory_limit;
170 		crashk_res.start = memblock_phys_alloc_range(crash_size,
171 							     PAGE_SIZE, 0, max);
172 		if (!crashk_res.start) {
173 			pr_err("crashkernel allocation failed\n");
174 			goto disable;
175 		}
176 	} else {
177 		ret = memblock_reserve(crashk_res.start, crash_size);
178 		if (unlikely(ret < 0)) {
179 			pr_err("crashkernel reservation failed - "
180 			       "memory is in use\n");
181 			goto disable;
182 		}
183 	}
184 
185 	crashk_res.end = crashk_res.start + crash_size - 1;
186 
187 	/*
188 	 * Crash kernel trumps memory limit
189 	 */
190 	if ((memblock_end_of_DRAM() - memory_limit) <= crashk_res.end) {
191 		memory_limit = 0;
192 		pr_info("Disabled memory limit for crashkernel\n");
193 	}
194 
195 	pr_info("Reserving %ldMB of memory at 0x%08lx "
196 		"for crashkernel (System RAM: %ldMB)\n",
197 		(unsigned long)(crash_size >> 20),
198 		(unsigned long)(crashk_res.start),
199 		(unsigned long)(memblock_phys_mem_size() >> 20));
200 
201 	return;
202 
203 disable:
204 	crashk_res.start = crashk_res.end = 0;
205 }
206