core_32.c

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