xref: /openbmc/linux/arch/mips/loongson64/reset.c (revision 8a9899c9)
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 
20 #include <loongson.h>
21 #include <boot_param.h>
22 
23 static void loongson_restart(char *command)
24 {
25 
26 	void (*fw_restart)(void) = (void *)loongson_sysconf.restart_addr;
27 
28 	fw_restart();
29 	while (1) {
30 		if (cpu_wait)
31 			cpu_wait();
32 	}
33 }
34 
35 static void loongson_poweroff(void)
36 {
37 	void (*fw_poweroff)(void) = (void *)loongson_sysconf.poweroff_addr;
38 
39 	fw_poweroff();
40 	while (1) {
41 		if (cpu_wait)
42 			cpu_wait();
43 	}
44 }
45 
46 static void loongson_halt(void)
47 {
48 	pr_notice("\n\n** You can safely turn off the power now **\n\n");
49 	while (1) {
50 		if (cpu_wait)
51 			cpu_wait();
52 	}
53 }
54 
55 #ifdef CONFIG_KEXEC
56 
57 /* 0X80000000~0X80200000 is safe */
58 #define MAX_ARGS	64
59 #define KEXEC_CTRL_CODE	0xFFFFFFFF80100000UL
60 #define KEXEC_ARGV_ADDR	0xFFFFFFFF80108000UL
61 #define KEXEC_ARGV_SIZE	COMMAND_LINE_SIZE
62 #define KEXEC_ENVP_SIZE	4800
63 
64 static int kexec_argc;
65 static int kdump_argc;
66 static void *kexec_argv;
67 static void *kdump_argv;
68 static void *kexec_envp;
69 
70 static int loongson_kexec_prepare(struct kimage *image)
71 {
72 	int i, argc = 0;
73 	unsigned int *argv;
74 	char *str, *ptr, *bootloader = "kexec";
75 
76 	/* argv at offset 0, argv[] at offset KEXEC_ARGV_SIZE/2 */
77 	if (image->type == KEXEC_TYPE_DEFAULT)
78 		argv = (unsigned int *)kexec_argv;
79 	else
80 		argv = (unsigned int *)kdump_argv;
81 
82 	argv[argc++] = (unsigned int)(KEXEC_ARGV_ADDR + KEXEC_ARGV_SIZE/2);
83 
84 	for (i = 0; i < image->nr_segments; i++) {
85 		if (!strncmp(bootloader, (char *)image->segment[i].buf,
86 				strlen(bootloader))) {
87 			/*
88 			 * convert command line string to array
89 			 * of parameters (as bootloader does).
90 			 */
91 			int offt;
92 			str = (char *)argv + KEXEC_ARGV_SIZE/2;
93 			memcpy(str, image->segment[i].buf, KEXEC_ARGV_SIZE/2);
94 			ptr = strchr(str, ' ');
95 
96 			while (ptr && (argc < MAX_ARGS)) {
97 				*ptr = '\0';
98 				if (ptr[1] != ' ') {
99 					offt = (int)(ptr - str + 1);
100 					argv[argc] = KEXEC_ARGV_ADDR + KEXEC_ARGV_SIZE/2 + offt;
101 					argc++;
102 				}
103 				ptr = strchr(ptr + 1, ' ');
104 			}
105 			break;
106 		}
107 	}
108 
109 	if (image->type == KEXEC_TYPE_DEFAULT)
110 		kexec_argc = argc;
111 	else
112 		kdump_argc = argc;
113 
114 	/* kexec/kdump need a safe page to save reboot_code_buffer */
115 	image->control_code_page = virt_to_page((void *)KEXEC_CTRL_CODE);
116 
117 	return 0;
118 }
119 
120 static void loongson_kexec_shutdown(void)
121 {
122 #ifdef CONFIG_SMP
123 	int cpu;
124 
125 	/* All CPUs go to reboot_code_buffer */
126 	for_each_possible_cpu(cpu)
127 		if (!cpu_online(cpu))
128 			cpu_device_up(get_cpu_device(cpu));
129 
130 	secondary_kexec_args[0] = TO_UNCAC(0x3ff01000);
131 #endif
132 	kexec_args[0] = kexec_argc;
133 	kexec_args[1] = fw_arg1;
134 	kexec_args[2] = fw_arg2;
135 	memcpy((void *)fw_arg1, kexec_argv, KEXEC_ARGV_SIZE);
136 	memcpy((void *)fw_arg2, kexec_envp, KEXEC_ENVP_SIZE);
137 }
138 
139 static void loongson_crash_shutdown(struct pt_regs *regs)
140 {
141 	default_machine_crash_shutdown(regs);
142 	kexec_args[0] = kdump_argc;
143 	kexec_args[1] = fw_arg1;
144 	kexec_args[2] = fw_arg2;
145 #ifdef CONFIG_SMP
146 	secondary_kexec_args[0] = TO_UNCAC(0x3ff01000);
147 #endif
148 	memcpy((void *)fw_arg1, kdump_argv, KEXEC_ARGV_SIZE);
149 	memcpy((void *)fw_arg2, kexec_envp, KEXEC_ENVP_SIZE);
150 }
151 
152 #endif
153 
154 static int __init mips_reboot_setup(void)
155 {
156 	_machine_restart = loongson_restart;
157 	_machine_halt = loongson_halt;
158 	pm_power_off = loongson_poweroff;
159 
160 #ifdef CONFIG_KEXEC
161 	kexec_argv = kmalloc(KEXEC_ARGV_SIZE, GFP_KERNEL);
162 	kdump_argv = kmalloc(KEXEC_ARGV_SIZE, GFP_KERNEL);
163 	kexec_envp = kmalloc(KEXEC_ENVP_SIZE, GFP_KERNEL);
164 	fw_arg1 = KEXEC_ARGV_ADDR;
165 	memcpy(kexec_envp, (void *)fw_arg2, KEXEC_ENVP_SIZE);
166 
167 	_machine_kexec_prepare = loongson_kexec_prepare;
168 	_machine_kexec_shutdown = loongson_kexec_shutdown;
169 	_machine_crash_shutdown = loongson_crash_shutdown;
170 #endif
171 
172 	return 0;
173 }
174 
175 arch_initcall(mips_reboot_setup);
176