xref: /openbmc/linux/arch/mips/loongson64/reset.c (revision 21ab7031)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *
4  * Copyright (C) 2007 Lemote, Inc. & Institute of Computing Technology
5  * Author: Fuxin Zhang, zhangfx@lemote.com
6  * Copyright (C) 2009 Lemote, Inc.
7  * Author: Zhangjin Wu, wuzhangjin@gmail.com
8  */
9 #include <linux/cpu.h>
10 #include <linux/delay.h>
11 #include <linux/init.h>
12 #include <linux/kexec.h>
13 #include <linux/pm.h>
14 #include <linux/slab.h>
15 
16 #include <asm/bootinfo.h>
17 #include <asm/idle.h>
18 #include <asm/reboot.h>
19 #include <asm/bug.h>
20 
21 #include <loongson.h>
22 #include <boot_param.h>
23 
24 static void loongson_restart(char *command)
25 {
26 
27 	void (*fw_restart)(void) = (void *)loongson_sysconf.restart_addr;
28 
29 	fw_restart();
30 	while (1) {
31 		if (cpu_wait)
32 			cpu_wait();
33 	}
34 }
35 
36 static void loongson_poweroff(void)
37 {
38 	void (*fw_poweroff)(void) = (void *)loongson_sysconf.poweroff_addr;
39 
40 	fw_poweroff();
41 	while (1) {
42 		if (cpu_wait)
43 			cpu_wait();
44 	}
45 }
46 
47 static void loongson_halt(void)
48 {
49 	pr_notice("\n\n** You can safely turn off the power now **\n\n");
50 	while (1) {
51 		if (cpu_wait)
52 			cpu_wait();
53 	}
54 }
55 
56 #ifdef CONFIG_KEXEC
57 
58 /* 0X80000000~0X80200000 is safe */
59 #define MAX_ARGS	64
60 #define KEXEC_CTRL_CODE	0xFFFFFFFF80100000UL
61 #define KEXEC_ARGV_ADDR	0xFFFFFFFF80108000UL
62 #define KEXEC_ARGV_SIZE	COMMAND_LINE_SIZE
63 #define KEXEC_ENVP_SIZE	4800
64 
65 static int kexec_argc;
66 static int kdump_argc;
67 static void *kexec_argv;
68 static void *kdump_argv;
69 static void *kexec_envp;
70 
71 static int loongson_kexec_prepare(struct kimage *image)
72 {
73 	int i, argc = 0;
74 	unsigned int *argv;
75 	char *str, *ptr, *bootloader = "kexec";
76 
77 	/* argv at offset 0, argv[] at offset KEXEC_ARGV_SIZE/2 */
78 	if (image->type == KEXEC_TYPE_DEFAULT)
79 		argv = (unsigned int *)kexec_argv;
80 	else
81 		argv = (unsigned int *)kdump_argv;
82 
83 	argv[argc++] = (unsigned int)(KEXEC_ARGV_ADDR + KEXEC_ARGV_SIZE/2);
84 
85 	for (i = 0; i < image->nr_segments; i++) {
86 		if (!strncmp(bootloader, (char *)image->segment[i].buf,
87 				strlen(bootloader))) {
88 			/*
89 			 * convert command line string to array
90 			 * of parameters (as bootloader does).
91 			 */
92 			int offt;
93 			str = (char *)argv + KEXEC_ARGV_SIZE/2;
94 			memcpy(str, image->segment[i].buf, KEXEC_ARGV_SIZE/2);
95 			ptr = strchr(str, ' ');
96 
97 			while (ptr && (argc < MAX_ARGS)) {
98 				*ptr = '\0';
99 				if (ptr[1] != ' ') {
100 					offt = (int)(ptr - str + 1);
101 					argv[argc] = KEXEC_ARGV_ADDR + KEXEC_ARGV_SIZE/2 + offt;
102 					argc++;
103 				}
104 				ptr = strchr(ptr + 1, ' ');
105 			}
106 			break;
107 		}
108 	}
109 
110 	if (image->type == KEXEC_TYPE_DEFAULT)
111 		kexec_argc = argc;
112 	else
113 		kdump_argc = argc;
114 
115 	/* kexec/kdump need a safe page to save reboot_code_buffer */
116 	image->control_code_page = virt_to_page((void *)KEXEC_CTRL_CODE);
117 
118 	return 0;
119 }
120 
121 static void loongson_kexec_shutdown(void)
122 {
123 #ifdef CONFIG_SMP
124 	int cpu;
125 
126 	/* All CPUs go to reboot_code_buffer */
127 	for_each_possible_cpu(cpu)
128 		if (!cpu_online(cpu))
129 			cpu_device_up(get_cpu_device(cpu));
130 
131 	secondary_kexec_args[0] = TO_UNCAC(0x3ff01000);
132 #endif
133 	kexec_args[0] = kexec_argc;
134 	kexec_args[1] = fw_arg1;
135 	kexec_args[2] = fw_arg2;
136 	memcpy((void *)fw_arg1, kexec_argv, KEXEC_ARGV_SIZE);
137 	memcpy((void *)fw_arg2, kexec_envp, KEXEC_ENVP_SIZE);
138 }
139 
140 static void loongson_crash_shutdown(struct pt_regs *regs)
141 {
142 	default_machine_crash_shutdown(regs);
143 	kexec_args[0] = kdump_argc;
144 	kexec_args[1] = fw_arg1;
145 	kexec_args[2] = fw_arg2;
146 #ifdef CONFIG_SMP
147 	secondary_kexec_args[0] = TO_UNCAC(0x3ff01000);
148 #endif
149 	memcpy((void *)fw_arg1, kdump_argv, KEXEC_ARGV_SIZE);
150 	memcpy((void *)fw_arg2, kexec_envp, KEXEC_ENVP_SIZE);
151 }
152 
153 #endif
154 
155 static int __init mips_reboot_setup(void)
156 {
157 	_machine_restart = loongson_restart;
158 	_machine_halt = loongson_halt;
159 	pm_power_off = loongson_poweroff;
160 
161 #ifdef CONFIG_KEXEC
162 	kexec_argv = kmalloc(KEXEC_ARGV_SIZE, GFP_KERNEL);
163 	if (WARN_ON(!kexec_argv))
164 		return -ENOMEM;
165 
166 	kdump_argv = kmalloc(KEXEC_ARGV_SIZE, GFP_KERNEL);
167 	if (WARN_ON(!kdump_argv))
168 		return -ENOMEM;
169 
170 	kexec_envp = kmalloc(KEXEC_ENVP_SIZE, GFP_KERNEL);
171 	if (WARN_ON(!kexec_envp))
172 		return -ENOMEM;
173 
174 	fw_arg1 = KEXEC_ARGV_ADDR;
175 	memcpy(kexec_envp, (void *)fw_arg2, KEXEC_ENVP_SIZE);
176 
177 	_machine_kexec_prepare = loongson_kexec_prepare;
178 	_machine_kexec_shutdown = loongson_kexec_shutdown;
179 	_machine_crash_shutdown = loongson_crash_shutdown;
180 #endif
181 
182 	return 0;
183 }
184 
185 arch_initcall(mips_reboot_setup);
186