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 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 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 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 85 static void power_timeout(unsigned long data) 86 { 87 sgi_machine_power_off(); 88 } 89 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 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 } 119 120 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 } 140 141 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 } 167 168 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 }; 184 185 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