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; 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 static irqreturn_t panel_int(int irq, void *dev_id) 143 { 144 unsigned int buttons; 145 146 buttons = sgioc->panel; 147 sgioc->panel = SGIOC_PANEL_POWERON | SGIOC_PANEL_POWERINTR; 148 149 if (sgint->istat1 & SGINT_ISTAT1_PWR) { 150 /* Wait until interrupt goes away */ 151 disable_irq(SGI_PANEL_IRQ); 152 init_timer(&debounce_timer); 153 debounce_timer.function = debounce; 154 debounce_timer.expires = jiffies + 5; 155 add_timer(&debounce_timer); 156 } 157 158 /* Power button was pressed 159 * ioc.ps page 22: "The Panel Register is called Power Control by Full 160 * House. Only lowest 2 bits are used. Guiness uses upper four bits 161 * for volume control". This is not true, all bits are pulled high 162 * on fullhouse */ 163 if (!(buttons & SGIOC_PANEL_POWERINTR)) 164 power_button(); 165 166 return IRQ_HANDLED; 167 } 168 169 static int panic_event(struct notifier_block *this, unsigned long event, 170 void *ptr) 171 { 172 if (machine_state & MACHINE_PANICED) 173 return NOTIFY_DONE; 174 machine_state |= MACHINE_PANICED; 175 176 blink_timer.data = PANIC_FREQ; 177 blink_timeout(PANIC_FREQ); 178 179 return NOTIFY_DONE; 180 } 181 182 static struct notifier_block panic_block = { 183 .notifier_call = panic_event, 184 }; 185 186 static int __init reboot_setup(void) 187 { 188 int res; 189 190 _machine_restart = sgi_machine_restart; 191 _machine_halt = sgi_machine_halt; 192 pm_power_off = sgi_machine_power_off; 193 194 res = request_irq(SGI_PANEL_IRQ, panel_int, 0, "Front Panel", NULL); 195 if (res) { 196 printk(KERN_ERR "Allocation of front panel IRQ failed\n"); 197 return res; 198 } 199 200 init_timer(&blink_timer); 201 blink_timer.function = blink_timeout; 202 atomic_notifier_chain_register(&panic_notifier_list, &panic_block); 203 204 return 0; 205 } 206 207 subsys_initcall(reboot_setup); 208