xref: /linux/arch/powerpc/kexec/core_32.c (revision f96a974170b749e3a56844e25b31d46a7233b6f6)
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 
18 typedef 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  */
30 void 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 
67 int machine_kexec_prepare(struct kimage *image)
68 {
69 	return 0;
70 }
71