1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * PPC32 code to handle Linux booting another kernel.
4 *
5 * Copyright (C) 2002-2003 Eric Biederman <ebiederm@xmission.com>
6 * GameCube/ppc32 port Copyright (C) 2004 Albert Herranz
7 * Copyright (C) 2005 IBM Corporation.
8 */
9
10#include <linux/kexec.h>
11#include <linux/mm.h>
12#include <linux/string.h>
13#include <asm/cacheflush.h>
14#include <asm/hw_irq.h>
15#include <asm/io.h>
16
17typedef void (*relocate_new_kernel_t)(
18 unsigned long indirection_page,
19 unsigned long reboot_code_buffer,
20 unsigned long start_address) __noreturn;
21
22/*
23 * This is a generic machine_kexec function suitable at least for
24 * non-OpenFirmware embedded platforms.
25 * It merely copies the image relocation code to the control page and
26 * jumps to it.
27 * A platform specific function may just call this one.
28 */
29void default_machine_kexec(struct kimage *image)
30{
31 extern const unsigned int relocate_new_kernel_size;
32 unsigned long page_list;
33 unsigned long reboot_code_buffer, reboot_code_buffer_phys;
34 relocate_new_kernel_t rnk;
35
36 /* Interrupts aren't acceptable while we reboot */
37 local_irq_disable();
38
39 /* mask each interrupt so we are in a more sane state for the
40 * kexec kernel */
41 machine_kexec_mask_interrupts();
42
43 page_list = image->head;
44
45 /* we need both effective and real address here */
46 reboot_code_buffer =
47 (unsigned long)page_address(image->control_code_page);
48 reboot_code_buffer_phys = virt_to_phys(address: (void *)reboot_code_buffer);
49
50 /* copy our kernel relocation code to the control code page */
51 memcpy((void *)reboot_code_buffer, relocate_new_kernel,
52 relocate_new_kernel_size);
53
54 flush_icache_range(start: reboot_code_buffer,
55 end: reboot_code_buffer + KEXEC_CONTROL_PAGE_SIZE);
56 printk(KERN_INFO "Bye!\n");
57
58 if (!IS_ENABLED(CONFIG_PPC_85xx) && !IS_ENABLED(CONFIG_44x))
59 relocate_new_kernel(page_list, reboot_code_buffer_phys, image->start);
60
61 /* now call it */
62 rnk = (relocate_new_kernel_t) reboot_code_buffer;
63 (*rnk)(page_list, reboot_code_buffer_phys, image->start);
64}
65
66int machine_kexec_prepare(struct kimage *image)
67{
68 return 0;
69}
70

source code of linux/arch/powerpc/kexec/core_32.c