xref: /openbmc/linux/arch/mips/sgi-ip22/ip22-reset.c (revision 64c70b1c)
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) 1997, 1998, 2001, 03, 05, 06 by Ralf Baechle
7  */
8 #include <linux/linkage.h>
9 #include <linux/init.h>
10 #include <linux/ds1286.h>
11 #include <linux/module.h>
12 #include <linux/interrupt.h>
13 #include <linux/kernel.h>
14 #include <linux/sched.h>
15 #include <linux/notifier.h>
16 #include <linux/pm.h>
17 #include <linux/timer.h>
18 
19 #include <asm/io.h>
20 #include <asm/irq.h>
21 #include <asm/system.h>
22 #include <asm/reboot.h>
23 #include <asm/sgialib.h>
24 #include <asm/sgi/ioc.h>
25 #include <asm/sgi/hpc3.h>
26 #include <asm/sgi/mc.h>
27 #include <asm/sgi/ip22.h>
28 
29 /*
30  * Just powerdown if init hasn't done after POWERDOWN_TIMEOUT seconds.
31  * I'm not sure if this feature is a good idea, for now it's here just to
32  * make the power button make behave just like under IRIX.
33  */
34 #define POWERDOWN_TIMEOUT	120
35 
36 /*
37  * Blink frequency during reboot grace period and when panicked.
38  */
39 #define POWERDOWN_FREQ		(HZ / 4)
40 #define PANIC_FREQ		(HZ / 8)
41 
42 static struct timer_list power_timer, blink_timer, debounce_timer, volume_timer;
43 
44 #define MACHINE_PANICED		1
45 #define MACHINE_SHUTTING_DOWN	2
46 
47 static int machine_state;
48 
49 static void __noreturn sgi_machine_power_off(void)
50 {
51 	unsigned int tmp;
52 
53 	local_irq_disable();
54 
55 	/* Disable watchdog */
56 	tmp = hpc3c0->rtcregs[RTC_CMD] & 0xff;
57 	hpc3c0->rtcregs[RTC_CMD] = tmp | RTC_WAM;
58 	hpc3c0->rtcregs[RTC_WSEC] = 0;
59 	hpc3c0->rtcregs[RTC_WHSEC] = 0;
60 
61 	while (1) {
62 		sgioc->panel = ~SGIOC_PANEL_POWERON;
63 		/* Good bye cruel world ...  */
64 
65 		/* If we're still running, we probably got sent an alarm
66 		   interrupt.  Read the flag to clear it.  */
67 		tmp = hpc3c0->rtcregs[RTC_HOURS_ALARM];
68 	}
69 }
70 
71 static void __noreturn sgi_machine_restart(char *command)
72 {
73 	if (machine_state & MACHINE_SHUTTING_DOWN)
74 		sgi_machine_power_off();
75 	sgimc->cpuctrl0 |= SGIMC_CCTRL0_SYSINIT;
76 	while (1);
77 }
78 
79 static void __noreturn sgi_machine_halt(void)
80 {
81 	if (machine_state & MACHINE_SHUTTING_DOWN)
82 		sgi_machine_power_off();
83 	ArcEnterInteractiveMode();
84 }
85 
86 static void power_timeout(unsigned long data)
87 {
88 	sgi_machine_power_off();
89 }
90 
91 static void blink_timeout(unsigned long data)
92 {
93 	/* XXX fix this for fullhouse  */
94 	sgi_ioc_reset ^= (SGIOC_RESET_LC0OFF|SGIOC_RESET_LC1OFF);
95 	sgioc->reset = sgi_ioc_reset;
96 
97 	mod_timer(&blink_timer, jiffies + data);
98 }
99 
100 static void debounce(unsigned long data)
101 {
102 	del_timer(&debounce_timer);
103 	if (sgint->istat1 & SGINT_ISTAT1_PWR) {
104 		/* Interrupt still being sent. */
105 		debounce_timer.expires = jiffies + (HZ / 20); /* 0.05s  */
106 		add_timer(&debounce_timer);
107 
108 		sgioc->panel = SGIOC_PANEL_POWERON | SGIOC_PANEL_POWERINTR |
109 			       SGIOC_PANEL_VOLDNINTR | SGIOC_PANEL_VOLDNHOLD |
110 			       SGIOC_PANEL_VOLUPINTR | SGIOC_PANEL_VOLUPHOLD;
111 
112 		return;
113 	}
114 
115 	if (machine_state & MACHINE_PANICED)
116 		sgimc->cpuctrl0 |= SGIMC_CCTRL0_SYSINIT;
117 
118 	enable_irq(SGI_PANEL_IRQ);
119 }
120 
121 static inline void power_button(void)
122 {
123 	if (machine_state & MACHINE_PANICED)
124 		return;
125 
126 	if ((machine_state & MACHINE_SHUTTING_DOWN) ||
127 			kill_cad_pid(SIGINT, 1)) {
128 		/* No init process or button pressed twice.  */
129 		sgi_machine_power_off();
130 	}
131 
132 	machine_state |= MACHINE_SHUTTING_DOWN;
133 	blink_timer.data = POWERDOWN_FREQ;
134 	blink_timeout(POWERDOWN_FREQ);
135 
136 	init_timer(&power_timer);
137 	power_timer.function = power_timeout;
138 	power_timer.expires = jiffies + POWERDOWN_TIMEOUT * HZ;
139 	add_timer(&power_timer);
140 }
141 
142 void (*indy_volume_button)(int) = NULL;
143 
144 EXPORT_SYMBOL(indy_volume_button);
145 
146 static inline void volume_up_button(unsigned long data)
147 {
148 	del_timer(&volume_timer);
149 
150 	if (indy_volume_button)
151 		indy_volume_button(1);
152 
153 	if (sgint->istat1 & SGINT_ISTAT1_PWR) {
154 		volume_timer.expires = jiffies + (HZ / 100);
155 		add_timer(&volume_timer);
156 	}
157 }
158 
159 static inline void volume_down_button(unsigned long data)
160 {
161 	del_timer(&volume_timer);
162 
163 	if (indy_volume_button)
164 		indy_volume_button(-1);
165 
166 	if (sgint->istat1 & SGINT_ISTAT1_PWR) {
167 		volume_timer.expires = jiffies + (HZ / 100);
168 		add_timer(&volume_timer);
169 	}
170 }
171 
172 static irqreturn_t panel_int(int irq, void *dev_id)
173 {
174 	unsigned int buttons;
175 
176 	buttons = sgioc->panel;
177 	sgioc->panel = SGIOC_PANEL_POWERON | SGIOC_PANEL_POWERINTR;
178 
179 	if (sgint->istat1 & SGINT_ISTAT1_PWR) {
180 		/* Wait until interrupt goes away */
181 		disable_irq(SGI_PANEL_IRQ);
182 		init_timer(&debounce_timer);
183 		debounce_timer.function = debounce;
184 		debounce_timer.expires = jiffies + 5;
185 		add_timer(&debounce_timer);
186 	}
187 
188 	/* Power button was pressed
189 	 * ioc.ps page 22: "The Panel Register is called Power Control by Full
190 	 * House. Only lowest 2 bits are used. Guiness uses upper four bits
191 	 * for volume control". This is not true, all bits are pulled high
192 	 * on fullhouse */
193 	if (ip22_is_fullhouse() || !(buttons & SGIOC_PANEL_POWERINTR)) {
194 		power_button();
195 		return IRQ_HANDLED;
196 	}
197 	/* TODO: mute/unmute */
198 	/* Volume up button was pressed */
199 	if (!(buttons & SGIOC_PANEL_VOLUPINTR)) {
200 		init_timer(&volume_timer);
201 		volume_timer.function = volume_up_button;
202 		volume_timer.expires = jiffies + (HZ / 100);
203 		add_timer(&volume_timer);
204 	}
205 	/* Volume down button was pressed */
206 	if (!(buttons & SGIOC_PANEL_VOLDNINTR)) {
207 		init_timer(&volume_timer);
208 		volume_timer.function = volume_down_button;
209 		volume_timer.expires = jiffies + (HZ / 100);
210 		add_timer(&volume_timer);
211 	}
212 
213 	return IRQ_HANDLED;
214 }
215 
216 static int panic_event(struct notifier_block *this, unsigned long event,
217                       void *ptr)
218 {
219 	if (machine_state & MACHINE_PANICED)
220 		return NOTIFY_DONE;
221 	machine_state |= MACHINE_PANICED;
222 
223 	blink_timer.data = PANIC_FREQ;
224 	blink_timeout(PANIC_FREQ);
225 
226 	return NOTIFY_DONE;
227 }
228 
229 static struct notifier_block panic_block = {
230 	.notifier_call	= panic_event,
231 };
232 
233 static int __init reboot_setup(void)
234 {
235 	_machine_restart = sgi_machine_restart;
236 	_machine_halt = sgi_machine_halt;
237 	pm_power_off = sgi_machine_power_off;
238 
239 	request_irq(SGI_PANEL_IRQ, panel_int, 0, "Front Panel", NULL);
240 	init_timer(&blink_timer);
241 	blink_timer.function = blink_timeout;
242 	atomic_notifier_chain_register(&panic_notifier_list, &panic_block);
243 
244 	return 0;
245 }
246 
247 subsys_initcall(reboot_setup);
248