aboutsummaryrefslogtreecommitdiffstats
path: root/arch/mips/sgi-ip32/ip32-reset.c
blob: 44b3470a0bbb71babcc9af5131d566d22aa317c5 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 2001 Keith M Wesolowski
 * Copyright (C) 2001 Paul Mundt
 * Copyright (C) 2003 Guido Guenther <agx@sigxcpu.org>
 */

#include <linux/compiler.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/notifier.h>
#include <linux/delay.h>
#include <linux/ds17287rtc.h>
#include <linux/interrupt.h>
#include <linux/pm.h>

#include <asm/addrspace.h>
#include <asm/irq.h>
#include <asm/reboot.h>
#include <asm/wbflush.h>
#include <asm/ip32/mace.h>
#include <asm/ip32/crime.h>
#include <asm/ip32/ip32_ints.h>

#define POWERDOWN_TIMEOUT	120
/*
 * Blink frequency during reboot grace period and when panicked.
 */
#define POWERDOWN_FREQ		(HZ / 4)
#define PANIC_FREQ		(HZ / 8)

static struct timer_list power_timer, blink_timer, debounce_timer;
static int has_panicked, shuting_down;

static void ip32_machine_restart(char *command) __noreturn;
static void ip32_machine_halt(void) __noreturn;
static void ip32_machine_power_off(void) __noreturn;

static void ip32_machine_restart(char *cmd)
{
	crime->control = CRIME_CONTROL_HARD_RESET;
	while (1);
}

static inline void ip32_machine_halt(void)
{
	ip32_machine_power_off();
}

static void ip32_machine_power_off(void)
{
	unsigned char reg_a, xctrl_a, xctrl_b;

	disable_irq(MACEISA_RTC_IRQ);
	reg_a = CMOS_READ(RTC_REG_A);

	/* setup for kickstart & wake-up (DS12287 Ref. Man. p. 19) */
	reg_a &= ~DS_REGA_DV2;
	reg_a |= DS_REGA_DV1;

	CMOS_WRITE(reg_a | DS_REGA_DV0, RTC_REG_A);
	wbflush();
	xctrl_b = CMOS_READ(DS_B1_XCTRL4B)
		   | DS_XCTRL4B_ABE | DS_XCTRL4B_KFE;
	CMOS_WRITE(xctrl_b, DS_B1_XCTRL4B);
	xctrl_a = CMOS_READ(DS_B1_XCTRL4A) & ~DS_XCTRL4A_IFS;
	CMOS_WRITE(xctrl_a, DS_B1_XCTRL4A);
	wbflush();
	/* adios amigos... */
	CMOS_WRITE(xctrl_a | DS_XCTRL4A_PAB, DS_B1_XCTRL4A);
	CMOS_WRITE(reg_a, RTC_REG_A);
	wbflush();
	while (1);
}

static void power_timeout(unsigned long data)
{
	ip32_machine_power_off();
}

static void blink_timeout(unsigned long data)
{
	unsigned long led = mace->perif.ctrl.misc ^ MACEISA_LED_RED;
	mace->perif.ctrl.misc = led;
	mod_timer(&blink_timer, jiffies + data);
}

static void debounce(unsigned long data)
{
	unsigned char reg_a, reg_c, xctrl_a;

	reg_c = CMOS_READ(RTC_INTR_FLAGS);
	reg_a = CMOS_READ(RTC_REG_A);
	CMOS_WRITE(reg_a | DS_REGA_DV0, RTC_REG_A);
	wbflush();
	xctrl_a = CMOS_READ(DS_B1_XCTRL4A);
	if ((xctrl_a & DS_XCTRL4A_IFS) || (reg_c & RTC_IRQF )) {
		/* Interrupt still being sent. */
		debounce_timer.expires = jiffies + 50;
		add_timer(&debounce_timer);

		/* clear interrupt source */
		CMOS_WRITE(xctrl_a & ~DS_XCTRL4A_IFS, DS_B1_XCTRL4A);
		CMOS_WRITE(reg_a & ~DS_REGA_DV0, RTC_REG_A);
		return;
	}
	CMOS_WRITE(reg_a & ~DS_REGA_DV0, RTC_REG_A);

	if (has_panicked)
		ip32_machine_restart(NULL);

	enable_irq(MACEISA_RTC_IRQ);
}

static inline void ip32_power_button(void)
{
	if (has_panicked)
		return;

	if (shuting_down || kill_cad_pid(SIGINT, 1)) {
		/* No init process or button pressed twice.  */
		ip32_machine_power_off();
	}

	shuting_down = 1;
	blink_timer.data = POWERDOWN_FREQ;
	blink_timeout(POWERDOWN_FREQ);

	init_timer(&power_timer);
	power_timer.function = power_timeout;
	power_timer.expires = jiffies + POWERDOWN_TIMEOUT * HZ;
	add_timer(&power_timer);
}

static irqreturn_t ip32_rtc_int(int irq, void *dev_id)
{
	unsigned char reg_c;

	reg_c = CMOS_READ(RTC_INTR_FLAGS);
	if (!(reg_c & RTC_IRQF)) {
		printk(KERN_WARNING
			"%s: RTC IRQ without RTC_IRQF\n", __func__);
	}
	/* Wait until interrupt goes away */
	disable_irq_nosync(MACEISA_RTC_IRQ);
	init_timer(&debounce_timer);
	debounce_timer.function = debounce;
	debounce_timer.expires = jiffies + 50;
	add_timer(&debounce_timer);

	printk(KERN_DEBUG "Power button pressed\n");
	ip32_power_button();
	return IRQ_HANDLED;
}

static int panic_event(struct notifier_block *this, unsigned long event,
		       void *ptr)
{
	unsigned long led;

	if (has_panicked)
		return NOTIFY_DONE;
	has_panicked = 1;

	/* turn off the green LED */
	led = mace->perif.ctrl.misc | MACEISA_LED_GREEN;
	mace->perif.ctrl.misc = led;

	blink_timer.data = PANIC_FREQ;
	blink_timeout(PANIC_FREQ);

	return NOTIFY_DONE;
}

static struct notifier_block panic_block = {
	.notifier_call = panic_event,
};

static __init int ip32_reboot_setup(void)
{
	/* turn on the green led only */
	unsigned long led = mace->perif.ctrl.misc;
	led |= MACEISA_LED_RED;
	led &= ~MACEISA_LED_GREEN;
	mace->perif.ctrl.misc = led;

	_machine_restart = ip32_machine_restart;
	_machine_halt = ip32_machine_halt;
	pm_power_off = ip32_machine_power_off;

	init_timer(&blink_timer);
	blink_timer.function = blink_timeout;
	atomic_notifier_chain_register(&panic_notifier_list, &panic_block);

	if (request_irq(MACEISA_RTC_IRQ, ip32_rtc_int, 0, "rtc", NULL))
		panic("Can't allocate MACEISA RTC IRQ");

	return 0;
}

subsys_initcall(ip32_reboot_setup);