1/*
2 * machine_kexec.c - handle transition of Linux booting another kernel
3 * Copyright (C) 2002-2003 Eric Biederman  <ebiederm@xmission.com>
4 *
5 * GameCube/ppc32 port Copyright (C) 2004 Albert Herranz
6 *
7 * This source code is licensed under the GNU General Public License,
8 * Version 2.  See the file COPYING for more details.
9 */
10
11#include <linux/mm.h>
12#include <linux/kexec.h>
13#include <linux/delay.h>
14#include <linux/reboot.h>
15#include <asm/pgtable.h>
16#include <asm/pgalloc.h>
17#include <asm/mmu_context.h>
18#include <asm/io.h>
19#include <asm/hw_irq.h>
20#include <asm/cacheflush.h>
21#include <asm/machdep.h>
22
23typedef NORET_TYPE void (*relocate_new_kernel_t)(
24				unsigned long indirection_page,
25				unsigned long reboot_code_buffer,
26				unsigned long start_address) ATTRIB_NORET;
27
28extern const unsigned char relocate_new_kernel[];
29extern const unsigned int relocate_new_kernel_size;
30
31void machine_shutdown(void)
32{
33	if (ppc_md.machine_shutdown)
34		ppc_md.machine_shutdown();
35}
36
37void machine_crash_shutdown(struct pt_regs *regs)
38{
39	if (ppc_md.machine_crash_shutdown)
40		ppc_md.machine_crash_shutdown();
41}
42
43/*
44 * Do what every setup is needed on image and the
45 * reboot code buffer to allow us to avoid allocations
46 * later.
47 */
48int machine_kexec_prepare(struct kimage *image)
49{
50	if (ppc_md.machine_kexec_prepare)
51		return ppc_md.machine_kexec_prepare(image);
52	/*
53	 * Fail if platform doesn't provide its own machine_kexec_prepare
54	 * implementation.
55	 */
56	return -ENOSYS;
57}
58
59void machine_kexec_cleanup(struct kimage *image)
60{
61	if (ppc_md.machine_kexec_cleanup)
62		ppc_md.machine_kexec_cleanup(image);
63}
64
65/*
66 * Do not allocate memory (or fail in any way) in machine_kexec().
67 * We are past the point of no return, committed to rebooting now.
68 */
69NORET_TYPE void machine_kexec(struct kimage *image)
70{
71	if (ppc_md.machine_kexec)
72		ppc_md.machine_kexec(image);
73	else {
74		/*
75		 * Fall back to normal restart if platform doesn't provide
76		 * its own kexec function, and user insist to kexec...
77		 */
78		machine_restart(NULL);
79	}
80	for(;;);
81}
82
83/*
84 * This is a generic machine_kexec function suitable at least for
85 * non-OpenFirmware embedded platforms.
86 * It merely copies the image relocation code to the control page and
87 * jumps to it.
88 * A platform specific function may just call this one.
89 */
90void machine_kexec_simple(struct kimage *image)
91{
92	unsigned long page_list;
93	unsigned long reboot_code_buffer, reboot_code_buffer_phys;
94	relocate_new_kernel_t rnk;
95
96	/* Interrupts aren't acceptable while we reboot */
97	local_irq_disable();
98
99	page_list = image->head;
100
101	/* we need both effective and real address here */
102	reboot_code_buffer =
103			(unsigned long)page_address(image->control_code_page);
104	reboot_code_buffer_phys = virt_to_phys((void *)reboot_code_buffer);
105
106	/* copy our kernel relocation code to the control code page */
107	memcpy((void *)reboot_code_buffer, relocate_new_kernel,
108						relocate_new_kernel_size);
109
110	flush_icache_range(reboot_code_buffer,
111				reboot_code_buffer + KEXEC_CONTROL_CODE_SIZE);
112	printk(KERN_INFO "Bye!\n");
113
114	/* now call it */
115	rnk = (relocate_new_kernel_t) reboot_code_buffer;
116	(*rnk)(page_list, reboot_code_buffer_phys, image->start);
117}
118