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/arch/mips/sgi-ip32/ip32-reset.c

https://bitbucket.org/thekraven/iscream_thunderc-2.6.35
C | 205 lines | 148 code | 37 blank | 20 comment | 11 complexity | b769e3708eaa99bbfbfd69425883a436 MD5 | raw file
Possible License(s): GPL-2.0, LGPL-2.0, AGPL-1.0
  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/init.h>
 12#include <linux/kernel.h>
 13#include <linux/sched.h>
 14#include <linux/notifier.h>
 15#include <linux/delay.h>
 16#include <linux/ds17287rtc.h>
 17#include <linux/interrupt.h>
 18#include <linux/pm.h>
 19
 20#include <asm/addrspace.h>
 21#include <asm/irq.h>
 22#include <asm/reboot.h>
 23#include <asm/system.h>
 24#include <asm/wbflush.h>
 25#include <asm/ip32/mace.h>
 26#include <asm/ip32/crime.h>
 27#include <asm/ip32/ip32_ints.h>
 28
 29#define POWERDOWN_TIMEOUT	120
 30/*
 31 * Blink frequency during reboot grace period and when panicked.
 32 */
 33#define POWERDOWN_FREQ		(HZ / 4)
 34#define PANIC_FREQ		(HZ / 8)
 35
 36static struct timer_list power_timer, blink_timer, debounce_timer;
 37static int has_panicked, shuting_down;
 38
 39static void ip32_machine_restart(char *command) __attribute__((noreturn));
 40static void ip32_machine_halt(void) __attribute__((noreturn));
 41static void ip32_machine_power_off(void) __attribute__((noreturn));
 42
 43static void ip32_machine_restart(char *cmd)
 44{
 45	crime->control = CRIME_CONTROL_HARD_RESET;
 46	while (1);
 47}
 48
 49static inline void ip32_machine_halt(void)
 50{
 51	ip32_machine_power_off();
 52}
 53
 54static void ip32_machine_power_off(void)
 55{
 56	unsigned char reg_a, xctrl_a, xctrl_b;
 57
 58	disable_irq(MACEISA_RTC_IRQ);
 59	reg_a = CMOS_READ(RTC_REG_A);
 60
 61	/* setup for kickstart & wake-up (DS12287 Ref. Man. p. 19) */
 62	reg_a &= ~DS_REGA_DV2;
 63	reg_a |= DS_REGA_DV1;
 64
 65	CMOS_WRITE(reg_a | DS_REGA_DV0, RTC_REG_A);
 66	wbflush();
 67	xctrl_b = CMOS_READ(DS_B1_XCTRL4B)
 68		   | DS_XCTRL4B_ABE | DS_XCTRL4B_KFE;
 69	CMOS_WRITE(xctrl_b, DS_B1_XCTRL4B);
 70	xctrl_a = CMOS_READ(DS_B1_XCTRL4A) & ~DS_XCTRL4A_IFS;
 71	CMOS_WRITE(xctrl_a, DS_B1_XCTRL4A);
 72	wbflush();
 73	/* adios amigos... */
 74	CMOS_WRITE(xctrl_a | DS_XCTRL4A_PAB, DS_B1_XCTRL4A);
 75	CMOS_WRITE(reg_a, RTC_REG_A);
 76	wbflush();
 77	while (1);
 78}
 79
 80static void power_timeout(unsigned long data)
 81{
 82	ip32_machine_power_off();
 83}
 84
 85static void blink_timeout(unsigned long data)
 86{
 87	unsigned long led = mace->perif.ctrl.misc ^ MACEISA_LED_RED;
 88	mace->perif.ctrl.misc = led;
 89	mod_timer(&blink_timer, jiffies + data);
 90}
 91
 92static void debounce(unsigned long data)
 93{
 94	unsigned char reg_a, reg_c, xctrl_a;
 95
 96	reg_c = CMOS_READ(RTC_INTR_FLAGS);
 97	reg_a = CMOS_READ(RTC_REG_A);
 98	CMOS_WRITE(reg_a | DS_REGA_DV0, RTC_REG_A);
 99	wbflush();
100	xctrl_a = CMOS_READ(DS_B1_XCTRL4A);
101	if ((xctrl_a & DS_XCTRL4A_IFS) || (reg_c & RTC_IRQF )) {
102		/* Interrupt still being sent. */
103		debounce_timer.expires = jiffies + 50;
104		add_timer(&debounce_timer);
105
106		/* clear interrupt source */
107		CMOS_WRITE(xctrl_a & ~DS_XCTRL4A_IFS, DS_B1_XCTRL4A);
108		CMOS_WRITE(reg_a & ~DS_REGA_DV0, RTC_REG_A);
109		return;
110	}
111	CMOS_WRITE(reg_a & ~DS_REGA_DV0, RTC_REG_A);
112
113	if (has_panicked)
114		ip32_machine_restart(NULL);
115
116	enable_irq(MACEISA_RTC_IRQ);
117}
118
119static inline void ip32_power_button(void)
120{
121	if (has_panicked)
122		return;
123
124	if (shuting_down || kill_cad_pid(SIGINT, 1)) {
125		/* No init process or button pressed twice.  */
126		ip32_machine_power_off();
127	}
128
129	shuting_down = 1;
130	blink_timer.data = POWERDOWN_FREQ;
131	blink_timeout(POWERDOWN_FREQ);
132
133	init_timer(&power_timer);
134	power_timer.function = power_timeout;
135	power_timer.expires = jiffies + POWERDOWN_TIMEOUT * HZ;
136	add_timer(&power_timer);
137}
138
139static irqreturn_t ip32_rtc_int(int irq, void *dev_id)
140{
141	unsigned char reg_c;
142
143	reg_c = CMOS_READ(RTC_INTR_FLAGS);
144	if (!(reg_c & RTC_IRQF)) {
145		printk(KERN_WARNING
146			"%s: RTC IRQ without RTC_IRQF\n", __func__);
147	}
148	/* Wait until interrupt goes away */
149	disable_irq_nosync(MACEISA_RTC_IRQ);
150	init_timer(&debounce_timer);
151	debounce_timer.function = debounce;
152	debounce_timer.expires = jiffies + 50;
153	add_timer(&debounce_timer);
154
155	printk(KERN_DEBUG "Power button pressed\n");
156	ip32_power_button();
157	return IRQ_HANDLED;
158}
159
160static int panic_event(struct notifier_block *this, unsigned long event,
161		       void *ptr)
162{
163	unsigned long led;
164
165	if (has_panicked)
166		return NOTIFY_DONE;
167	has_panicked = 1;
168
169	/* turn off the green LED */
170	led = mace->perif.ctrl.misc | MACEISA_LED_GREEN;
171	mace->perif.ctrl.misc = led;
172
173	blink_timer.data = PANIC_FREQ;
174	blink_timeout(PANIC_FREQ);
175
176	return NOTIFY_DONE;
177}
178
179static struct notifier_block panic_block = {
180	.notifier_call = panic_event,
181};
182
183static __init int ip32_reboot_setup(void)
184{
185	/* turn on the green led only */
186	unsigned long led = mace->perif.ctrl.misc;
187	led |= MACEISA_LED_RED;
188	led &= ~MACEISA_LED_GREEN;
189	mace->perif.ctrl.misc = led;
190
191	_machine_restart = ip32_machine_restart;
192	_machine_halt = ip32_machine_halt;
193	pm_power_off = ip32_machine_power_off;
194
195	init_timer(&blink_timer);
196	blink_timer.function = blink_timeout;
197	atomic_notifier_chain_register(&panic_notifier_list, &panic_block);
198
199	if (request_irq(MACEISA_RTC_IRQ, ip32_rtc_int, 0, "rtc", NULL))
200		panic("Can't allocate MACEISA RTC IRQ");
201
202	return 0;
203}
204
205subsys_initcall(ip32_reboot_setup);