xref: /openbmc/linux/arch/mips/sgi-ip22/ip22-reset.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
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, 2003 by Ralf Baechle
7  */
8 #include <linux/init.h>
9 #include <linux/ds1286.h>
10 #include <linux/module.h>
11 #include <linux/interrupt.h>
12 #include <linux/kernel.h>
13 #include <linux/sched.h>
14 #include <linux/notifier.h>
15 #include <linux/timer.h>
16 
17 #include <asm/io.h>
18 #include <asm/irq.h>
19 #include <asm/system.h>
20 #include <asm/reboot.h>
21 #include <asm/sgialib.h>
22 #include <asm/sgi/ioc.h>
23 #include <asm/sgi/hpc3.h>
24 #include <asm/sgi/mc.h>
25 #include <asm/sgi/ip22.h>
26 
27 /*
28  * Just powerdown if init hasn't done after POWERDOWN_TIMEOUT seconds.
29  * I'm not sure if this feature is a good idea, for now it's here just to
30  * make the power button make behave just like under IRIX.
31  */
32 #define POWERDOWN_TIMEOUT	120
33 
34 /*
35  * Blink frequency during reboot grace period and when paniced.
36  */
37 #define POWERDOWN_FREQ		(HZ / 4)
38 #define PANIC_FREQ		(HZ / 8)
39 
40 static struct timer_list power_timer, blink_timer, debounce_timer, volume_timer;
41 
42 #define MACHINE_PANICED		1
43 #define MACHINE_SHUTTING_DOWN	2
44 static int machine_state = 0;
45 
46 static void sgi_machine_restart(char *command) __attribute__((noreturn));
47 static void sgi_machine_halt(void) __attribute__((noreturn));
48 static void sgi_machine_power_off(void) __attribute__((noreturn));
49 
50 static void sgi_machine_restart(char *command)
51 {
52 	if (machine_state & MACHINE_SHUTTING_DOWN)
53 		sgi_machine_power_off();
54 	sgimc->cpuctrl0 |= SGIMC_CCTRL0_SYSINIT;
55 	while (1);
56 }
57 
58 static void sgi_machine_halt(void)
59 {
60 	if (machine_state & MACHINE_SHUTTING_DOWN)
61 		sgi_machine_power_off();
62 	ArcEnterInteractiveMode();
63 }
64 
65 static void sgi_machine_power_off(void)
66 {
67 	unsigned int tmp;
68 
69 	local_irq_disable();
70 
71 	/* Disable watchdog */
72 	tmp = hpc3c0->rtcregs[RTC_CMD] & 0xff;
73 	hpc3c0->rtcregs[RTC_CMD] = tmp | RTC_WAM;
74 	hpc3c0->rtcregs[RTC_WSEC] = 0;
75 	hpc3c0->rtcregs[RTC_WHSEC] = 0;
76 
77 	while (1) {
78 		sgioc->panel = ~SGIOC_PANEL_POWERON;
79 		/* Good bye cruel world ...  */
80 
81 		/* If we're still running, we probably got sent an alarm
82 		   interrupt.  Read the flag to clear it.  */
83 		tmp = hpc3c0->rtcregs[RTC_HOURS_ALARM];
84 	}
85 }
86 
87 static void power_timeout(unsigned long data)
88 {
89 	sgi_machine_power_off();
90 }
91 
92 static void blink_timeout(unsigned long data)
93 {
94 	/* XXX fix this for fullhouse  */
95 	sgi_ioc_reset ^= (SGIOC_RESET_LC0OFF|SGIOC_RESET_LC1OFF);
96 	sgioc->reset = sgi_ioc_reset;
97 
98 	mod_timer(&blink_timer, jiffies+data);
99 }
100 
101 static void debounce(unsigned long data)
102 {
103 	del_timer(&debounce_timer);
104 	if (sgint->istat1 & SGINT_ISTAT1_PWR) {
105 		/* Interrupt still being sent. */
106 		debounce_timer.expires = jiffies + 5; /* 0.05s  */
107 		add_timer(&debounce_timer);
108 
109 		sgioc->panel = SGIOC_PANEL_POWERON | SGIOC_PANEL_POWERINTR |
110 			       SGIOC_PANEL_VOLDNINTR | SGIOC_PANEL_VOLDNHOLD |
111 			       SGIOC_PANEL_VOLUPINTR | SGIOC_PANEL_VOLUPHOLD;
112 
113 		return;
114 	}
115 
116 	if (machine_state & MACHINE_PANICED)
117 		sgimc->cpuctrl0 |= SGIMC_CCTRL0_SYSINIT;
118 
119 	enable_irq(SGI_PANEL_IRQ);
120 }
121 
122 static inline void power_button(void)
123 {
124 	if (machine_state & MACHINE_PANICED)
125 		return;
126 
127 	if ((machine_state & MACHINE_SHUTTING_DOWN) || kill_proc(1,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 + 1;
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 + 1;
168 		add_timer(&volume_timer);
169 	}
170 }
171 
172 static irqreturn_t panel_int(int irq, void *dev_id, struct pt_regs *regs)
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 + 1;
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 + 1;
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 	_machine_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 	notifier_chain_register(&panic_notifier_list, &panic_block);
243 
244 	return 0;
245 }
246 
247 subsys_initcall(reboot_setup);
248