xref: /linux/arch/mips/sgi-ip32/ip32-reset.c (revision 06d07429858317ded2db7986113a9e0129cd599b)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 2001 Keith M Wesolowski
7  * Copyright (C) 2001 Paul Mundt
8  * Copyright (C) 2003 Guido Guenther <agx@sigxcpu.org>
9  */
10 
11 #include <linux/compiler.h>
12 #include <linux/init.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/panic_notifier.h>
16 #include <linux/sched.h>
17 #include <linux/sched/signal.h>
18 #include <linux/notifier.h>
19 #include <linux/delay.h>
20 #include <linux/rtc/ds1685.h>
21 #include <linux/interrupt.h>
22 #include <linux/pm.h>
23 
24 #include <asm/addrspace.h>
25 #include <asm/irq.h>
26 #include <asm/reboot.h>
27 #include <asm/wbflush.h>
28 #include <asm/ip32/mace.h>
29 #include <asm/ip32/crime.h>
30 #include <asm/ip32/ip32_ints.h>
31 
32 #include "ip32-common.h"
33 
34 #define POWERDOWN_TIMEOUT	120
35 /*
36  * Blink frequency during reboot grace period and when panicked.
37  */
38 #define POWERDOWN_FREQ		(HZ / 4)
39 #define PANIC_FREQ		(HZ / 8)
40 
41 extern struct platform_device ip32_rtc_device;
42 
43 static struct timer_list power_timer, blink_timer;
44 static unsigned long blink_timer_timeout;
45 static int has_panicked, shutting_down;
46 
ip32_poweroff(void * data)47 static __noreturn void ip32_poweroff(void *data)
48 {
49 	void (*poweroff_func)(struct platform_device *) =
50 		symbol_get(ds1685_rtc_poweroff);
51 
52 #ifdef CONFIG_MODULES
53 	/* If the first __symbol_get failed, our module wasn't loaded. */
54 	if (!poweroff_func) {
55 		request_module("rtc-ds1685");
56 		poweroff_func = symbol_get(ds1685_rtc_poweroff);
57 	}
58 #endif
59 
60 	if (!poweroff_func)
61 		pr_emerg("RTC not available for power-off.  Spinning forever ...\n");
62 	else {
63 		(*poweroff_func)((struct platform_device *)data);
64 		symbol_put(ds1685_rtc_poweroff);
65 	}
66 
67 	unreachable();
68 }
69 
70 static void ip32_machine_restart(char *cmd) __noreturn;
ip32_machine_restart(char * cmd)71 static void ip32_machine_restart(char *cmd)
72 {
73 	msleep(20);
74 	crime->control = CRIME_CONTROL_HARD_RESET;
75 	unreachable();
76 }
77 
blink_timeout(struct timer_list * unused)78 static void blink_timeout(struct timer_list *unused)
79 {
80 	unsigned long led = mace->perif.ctrl.misc ^ MACEISA_LED_RED;
81 	mace->perif.ctrl.misc = led;
82 	mod_timer(&blink_timer, jiffies + blink_timer_timeout);
83 }
84 
ip32_machine_halt(void)85 static void ip32_machine_halt(void)
86 {
87 	ip32_poweroff(&ip32_rtc_device);
88 }
89 
power_timeout(struct timer_list * unused)90 static void power_timeout(struct timer_list *unused)
91 {
92 	ip32_poweroff(&ip32_rtc_device);
93 }
94 
ip32_prepare_poweroff(void)95 void ip32_prepare_poweroff(void)
96 {
97 	if (has_panicked)
98 		return;
99 
100 	if (shutting_down || kill_cad_pid(SIGINT, 1)) {
101 		/* No init process or button pressed twice.  */
102 		ip32_poweroff(&ip32_rtc_device);
103 	}
104 
105 	shutting_down = 1;
106 	blink_timer_timeout = POWERDOWN_FREQ;
107 	blink_timeout(&blink_timer);
108 
109 	timer_setup(&power_timer, power_timeout, 0);
110 	power_timer.expires = jiffies + POWERDOWN_TIMEOUT * HZ;
111 	add_timer(&power_timer);
112 }
113 
panic_event(struct notifier_block * this,unsigned long event,void * ptr)114 static int panic_event(struct notifier_block *this, unsigned long event,
115 		       void *ptr)
116 {
117 	unsigned long led;
118 
119 	if (has_panicked)
120 		return NOTIFY_DONE;
121 	has_panicked = 1;
122 
123 	/* turn off the green LED */
124 	led = mace->perif.ctrl.misc | MACEISA_LED_GREEN;
125 	mace->perif.ctrl.misc = led;
126 
127 	blink_timer_timeout = PANIC_FREQ;
128 	blink_timeout(&blink_timer);
129 
130 	return NOTIFY_DONE;
131 }
132 
133 static struct notifier_block panic_block = {
134 	.notifier_call = panic_event,
135 };
136 
ip32_reboot_setup(void)137 static __init int ip32_reboot_setup(void)
138 {
139 	/* turn on the green led only */
140 	unsigned long led = mace->perif.ctrl.misc;
141 	led |= MACEISA_LED_RED;
142 	led &= ~MACEISA_LED_GREEN;
143 	mace->perif.ctrl.misc = led;
144 
145 	_machine_restart = ip32_machine_restart;
146 	_machine_halt = ip32_machine_halt;
147 	pm_power_off = ip32_machine_halt;
148 
149 	timer_setup(&blink_timer, blink_timeout, 0);
150 	atomic_notifier_chain_register(&panic_notifier_list, &panic_block);
151 
152 	return 0;
153 }
154 
155 subsys_initcall(ip32_reboot_setup);
156