xref: /openbmc/linux/arch/m68k/kernel/machine_kexec.c (revision f4356947)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * machine_kexec.c - handle transition of Linux booting another kernel
4  */
5 #include <linux/compiler.h>
6 #include <linux/kexec.h>
7 #include <linux/mm.h>
8 #include <linux/delay.h>
9 #include <linux/reboot.h>
10 
11 #include <asm/cacheflush.h>
12 #include <asm/page.h>
13 #include <asm/setup.h>
14 
15 extern const unsigned char relocate_new_kernel[];
16 extern const size_t relocate_new_kernel_size;
17 
18 int machine_kexec_prepare(struct kimage *kimage)
19 {
20 	return 0;
21 }
22 
23 void machine_kexec_cleanup(struct kimage *kimage)
24 {
25 }
26 
27 void machine_shutdown(void)
28 {
29 }
30 
31 void machine_crash_shutdown(struct pt_regs *regs)
32 {
33 }
34 
35 typedef void (*relocate_kernel_t)(unsigned long ptr,
36 				  unsigned long start,
37 				  unsigned long cpu_mmu_flags) __noreturn;
38 
39 void machine_kexec(struct kimage *image)
40 {
41 	void *reboot_code_buffer;
42 	unsigned long cpu_mmu_flags;
43 
44 	reboot_code_buffer = page_address(image->control_code_page);
45 
46 	memcpy(reboot_code_buffer, relocate_new_kernel,
47 	       relocate_new_kernel_size);
48 
49 	/*
50 	 * we do not want to be bothered.
51 	 */
52 	local_irq_disable();
53 
54 	pr_info("Will call new kernel at 0x%08lx. Bye...\n", image->start);
55 	__flush_cache_all();
56 	cpu_mmu_flags = m68k_cputype | m68k_mmutype << 8;
57 	((relocate_kernel_t) reboot_code_buffer)(image->head & PAGE_MASK,
58 						 image->start,
59 						 cpu_mmu_flags);
60 }
61