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