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 
17 typedef 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  */
default_machine_kexec(struct kimage * image)29 void 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((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(reboot_code_buffer,
55 				reboot_code_buffer + KEXEC_CONTROL_PAGE_SIZE);
56 	printk(KERN_INFO "Bye!\n");
57 
58 	if (!IS_ENABLED(CONFIG_FSL_BOOKE) && !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 
machine_kexec_prepare(struct kimage * image)66 int machine_kexec_prepare(struct kimage *image)
67 {
68 	return 0;
69 }
70