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	volatile 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	volatile unsigned char reg_a, reg_c, xctrl_a;
95
96	reg_c = CMOS_READ(RTC_INTR_FLAGS);
97	CMOS_WRITE(reg_a | DS_REGA_DV0, RTC_REG_A);
98	wbflush();
99	xctrl_a = CMOS_READ(DS_B1_XCTRL4A);
100	if ((xctrl_a & DS_XCTRL4A_IFS) || (reg_c & RTC_IRQF )) {
101		/* Interrupt still being sent. */
102		debounce_timer.expires = jiffies + 50;
103		add_timer(&debounce_timer);
104
105		/* clear interrupt source */
106		CMOS_WRITE(xctrl_a & ~DS_XCTRL4A_IFS, DS_B1_XCTRL4A);
107		CMOS_WRITE(reg_a & ~DS_REGA_DV0, RTC_REG_A);
108		return;
109	}
110	CMOS_WRITE(reg_a & ~DS_REGA_DV0, RTC_REG_A);
111
112	if (has_panicked)
113		ip32_machine_restart(NULL);
114
115	enable_irq(MACEISA_RTC_IRQ);
116}
117
118static inline void ip32_power_button(void)
119{
120	if (has_panicked)
121		return;
122
123	if (shuting_down || kill_cad_pid(SIGINT, 1)) {
124		/* No init process or button pressed twice.  */
125		ip32_machine_power_off();
126	}
127
128	shuting_down = 1;
129	blink_timer.data = POWERDOWN_FREQ;
130	blink_timeout(POWERDOWN_FREQ);
131
132	init_timer(&power_timer);
133	power_timer.function = power_timeout;
134	power_timer.expires = jiffies + POWERDOWN_TIMEOUT * HZ;
135	add_timer(&power_timer);
136}
137
138static irqreturn_t ip32_rtc_int(int irq, void *dev_id)
139{
140	volatile unsigned char reg_c;
141
142	reg_c = CMOS_READ(RTC_INTR_FLAGS);
143	if (!(reg_c & RTC_IRQF)) {
144		printk(KERN_WARNING
145			"%s: RTC IRQ without RTC_IRQF\n", __FUNCTION__);
146	}
147	/* Wait until interrupt goes away */
148	disable_irq(MACEISA_RTC_IRQ);
149	init_timer(&debounce_timer);
150	debounce_timer.function = debounce;
151	debounce_timer.expires = jiffies + 50;
152	add_timer(&debounce_timer);
153
154	printk(KERN_DEBUG "Power button pressed\n");
155	ip32_power_button();
156	return IRQ_HANDLED;
157}
158
159static int panic_event(struct notifier_block *this, unsigned long event,
160		       void *ptr)
161{
162	unsigned long led;
163
164	if (has_panicked)
165		return NOTIFY_DONE;
166	has_panicked = 1;
167
168	/* turn off the green LED */
169	led = mace->perif.ctrl.misc | MACEISA_LED_GREEN;
170	mace->perif.ctrl.misc = led;
171
172	blink_timer.data = PANIC_FREQ;
173	blink_timeout(PANIC_FREQ);
174
175	return NOTIFY_DONE;
176}
177
178static struct notifier_block panic_block = {
179	.notifier_call = panic_event,
180};
181
182static __init int ip32_reboot_setup(void)
183{
184	/* turn on the green led only */
185	unsigned long led = mace->perif.ctrl.misc;
186	led |= MACEISA_LED_RED;
187	led &= ~MACEISA_LED_GREEN;
188	mace->perif.ctrl.misc = led;
189
190	_machine_restart = ip32_machine_restart;
191	_machine_halt = ip32_machine_halt;
192	pm_power_off = ip32_machine_power_off;
193
194	init_timer(&blink_timer);
195	blink_timer.function = blink_timeout;
196	atomic_notifier_chain_register(&panic_notifier_list, &panic_block);
197
198	request_irq(MACEISA_RTC_IRQ, ip32_rtc_int, 0, "rtc", NULL);
199
200	return 0;
201}
202
203subsys_initcall(ip32_reboot_setup);
204