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/panic_notifier.h> 15 #include <linux/pm.h> 16 #include <linux/timer.h> 17 18 #include <asm/io.h> 19 #include <asm/irq.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 panicked. 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; 41 static unsigned long blink_timer_timeout; 42 43 #define MACHINE_PANICKED 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(struct timer_list *unused) 86 { 87 sgi_machine_power_off(); 88 } 89 90 static void blink_timeout(struct timer_list *unused) 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 + blink_timer_timeout); 97 } 98 99 static void debounce(struct timer_list *unused) 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_PANICKED) 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_PANICKED) 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_timeout = POWERDOWN_FREQ; 133 blink_timeout(&blink_timer); 134 135 timer_setup(&power_timer, power_timeout, 0); 136 power_timer.expires = jiffies + POWERDOWN_TIMEOUT * HZ; 137 add_timer(&power_timer); 138 } 139 140 static irqreturn_t panel_int(int irq, void *dev_id) 141 { 142 unsigned int buttons; 143 144 buttons = sgioc->panel; 145 sgioc->panel = SGIOC_PANEL_POWERON | SGIOC_PANEL_POWERINTR; 146 147 if (sgint->istat1 & SGINT_ISTAT1_PWR) { 148 /* Wait until interrupt goes away */ 149 disable_irq_nosync(SGI_PANEL_IRQ); 150 timer_setup(&debounce_timer, debounce, 0); 151 debounce_timer.expires = jiffies + 5; 152 add_timer(&debounce_timer); 153 } 154 155 /* Power button was pressed 156 * ioc.ps page 22: "The Panel Register is called Power Control by Full 157 * House. Only lowest 2 bits are used. Guiness uses upper four bits 158 * for volume control". This is not true, all bits are pulled high 159 * on fullhouse */ 160 if (!(buttons & SGIOC_PANEL_POWERINTR)) 161 power_button(); 162 163 return IRQ_HANDLED; 164 } 165 166 static int panic_event(struct notifier_block *this, unsigned long event, 167 void *ptr) 168 { 169 if (machine_state & MACHINE_PANICKED) 170 return NOTIFY_DONE; 171 machine_state |= MACHINE_PANICKED; 172 173 blink_timer_timeout = PANIC_FREQ; 174 blink_timeout(&blink_timer); 175 176 return NOTIFY_DONE; 177 } 178 179 static struct notifier_block panic_block = { 180 .notifier_call = panic_event, 181 }; 182 183 static int __init reboot_setup(void) 184 { 185 int res; 186 187 _machine_restart = sgi_machine_restart; 188 _machine_halt = sgi_machine_halt; 189 pm_power_off = sgi_machine_power_off; 190 191 res = request_irq(SGI_PANEL_IRQ, panel_int, 0, "Front Panel", NULL); 192 if (res) { 193 printk(KERN_ERR "Allocation of front panel IRQ failed\n"); 194 return res; 195 } 196 197 timer_setup(&blink_timer, blink_timeout, 0); 198 atomic_notifier_chain_register(&panic_notifier_list, &panic_block); 199 200 return 0; 201 } 202 203 subsys_initcall(reboot_setup); 204