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/rtc/ds1286.h>
11 #include <linux/interrupt.h>
12 #include <linux/kernel.h>
13 #include <linux/sched/signal.h>
14 #include <linux/notifier.h>
15 #include <linux/panic_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 static unsigned long blink_timer_timeout;
43
44 #define MACHINE_PANICED 1
45 #define MACHINE_SHUTTING_DOWN 2
46
47 static int machine_state;
48
sgi_machine_power_off(void)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
sgi_machine_restart(char * command)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
sgi_machine_halt(void)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
power_timeout(struct timer_list * unused)86 static void power_timeout(struct timer_list *unused)
87 {
88 sgi_machine_power_off();
89 }
90
blink_timeout(struct timer_list * unused)91 static void blink_timeout(struct timer_list *unused)
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 + blink_timer_timeout);
98 }
99
debounce(struct timer_list * unused)100 static void debounce(struct timer_list *unused)
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
power_button(void)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_timeout = POWERDOWN_FREQ;
134 blink_timeout(&blink_timer);
135
136 timer_setup(&power_timer, power_timeout, 0);
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 timer_setup(&debounce_timer, debounce, 0);
152 debounce_timer.expires = jiffies + 5;
153 add_timer(&debounce_timer);
154 }
155
156 /* Power button was pressed
157 * ioc.ps page 22: "The Panel Register is called Power Control by Full
158 * House. Only lowest 2 bits are used. Guiness uses upper four bits
159 * for volume control". This is not true, all bits are pulled high
160 * on fullhouse */
161 if (!(buttons & SGIOC_PANEL_POWERINTR))
162 power_button();
163
164 return IRQ_HANDLED;
165 }
166
panic_event(struct notifier_block * this,unsigned long event,void * ptr)167 static int panic_event(struct notifier_block *this, unsigned long event,
168 void *ptr)
169 {
170 if (machine_state & MACHINE_PANICED)
171 return NOTIFY_DONE;
172 machine_state |= MACHINE_PANICED;
173
174 blink_timer_timeout = PANIC_FREQ;
175 blink_timeout(&blink_timer);
176
177 return NOTIFY_DONE;
178 }
179
180 static struct notifier_block panic_block = {
181 .notifier_call = panic_event,
182 };
183
reboot_setup(void)184 static int __init reboot_setup(void)
185 {
186 int res;
187
188 _machine_restart = sgi_machine_restart;
189 _machine_halt = sgi_machine_halt;
190 pm_power_off = sgi_machine_power_off;
191
192 res = request_irq(SGI_PANEL_IRQ, panel_int, 0, "Front Panel", NULL);
193 if (res) {
194 printk(KERN_ERR "Allocation of front panel IRQ failed\n");
195 return res;
196 }
197
198 timer_setup(&blink_timer, blink_timeout, 0);
199 atomic_notifier_chain_register(&panic_notifier_list, &panic_block);
200
201 return 0;
202 }
203
204 subsys_initcall(reboot_setup);
205
