text: /*
   * This file is subject to the terms and conditions of the GNU General Public
   * License.  See the file "COPYING" in the main directory of this archive
   * for more details.
   *
   * Copyright (C) 2001 Keith M Wesolowski
   * Copyright (C) 2001 Paul Mundt
   * Copyright (C) 2003 Guido Guenther <agx@sigxcpu.org>
   */
  
  #include <linux/compiler.h>
  #include <linux/init.h>
  #include <linux/kernel.h>
  #include <linux/sched.h>
  #include <linux/notifier.h>
  #include <linux/delay.h>
  #include <linux/ds17287rtc.h>
  #include <linux/interrupt.h>
  #include <linux/pm.h>
  
  #include <asm/addrspace.h>
  #include <asm/irq.h>
  #include <asm/reboot.h>
  #include <asm/wbflush.h>
  #include <asm/ip32/mace.h>
  #include <asm/ip32/crime.h>
  #include <asm/ip32/ip32_ints.h>
  
  #define POWERDOWN_TIMEOUT	120
  /*
   * Blink frequency during reboot grace period and when panicked.
   */
  #define POWERDOWN_FREQ		(HZ / 4)
  #define PANIC_FREQ		(HZ / 8)
  
  static struct timer_list power_timer, blink_timer, debounce_timer;
  static int has_panicked, shuting_down;
  
  static void ip32_machine_restart(char *command) __noreturn;
  static void ip32_machine_halt(void) __noreturn;
  static void ip32_machine_power_off(void) __noreturn;
  
  static void ip32_machine_restart(char *cmd)
  {
  	crime->control = CRIME_CONTROL_HARD_RESET;
  	while (1);
  }
  
  static inline void ip32_machine_halt(void)
  {
  	ip32_machine_power_off();
  }
  
  static void ip32_machine_power_off(void)
  {
  	unsigned char reg_a, xctrl_a, xctrl_b;
  
  	disable_irq(MACEISA_RTC_IRQ);
  	reg_a = CMOS_READ(RTC_REG_A);
  
  	/* setup for kickstart & wake-up (DS12287 Ref. Man. p. 19) */
  	reg_a &= ~DS_REGA_DV2;
  	reg_a |= DS_REGA_DV1;
  
  	CMOS_WRITE(reg_a | DS_REGA_DV0, RTC_REG_A);
  	wbflush();
  	xctrl_b = CMOS_READ(DS_B1_XCTRL4B)
  		   | DS_XCTRL4B_ABE | DS_XCTRL4B_KFE;
  	CMOS_WRITE(xctrl_b, DS_B1_XCTRL4B);
  	xctrl_a = CMOS_READ(DS_B1_XCTRL4A) & ~DS_XCTRL4A_IFS;
  	CMOS_WRITE(xctrl_a, DS_B1_XCTRL4A);
  	wbflush();
  	/* adios amigos... */
  	CMOS_WRITE(xctrl_a | DS_XCTRL4A_PAB, DS_B1_XCTRL4A);
  	CMOS_WRITE(reg_a, RTC_REG_A);
  	wbflush();
  	while (1);
  }
  
  static void power_timeout(unsigned long data)
  {
  	ip32_machine_power_off();
  }
  
  static void blink_timeout(unsigned long data)
  {
  	unsigned long led = mace->perif.ctrl.misc ^ MACEISA_LED_RED;
  	mace->perif.ctrl.misc = led;
  	mod_timer(&blink_timer, jiffies + data);
  }
  
  static void debounce(unsigned long data)
  {
  	unsigned char reg_a, reg_c, xctrl_a;
  
  	reg_c = CMOS_READ(RTC_INTR_FLAGS);
  	reg_a = CMOS_READ(RTC_REG_A);
  	CMOS_WRITE(reg_a | DS_REGA_DV0, RTC_REG_A);
  	wbflush();
  	xctrl_a = CMOS_READ(DS_B1_XCTRL4A);
  	if ((xctrl_a & DS_XCTRL4A_IFS) || (reg_c & RTC_IRQF )) {
  		/* Interrupt still being sent. */
  		debounce_timer.expires = jiffies + 50;
  		add_timer(&debounce_timer);
  
  		/* clear interrupt source */
  		CMOS_WRITE(xctrl_a & ~DS_XCTRL4A_IFS, DS_B1_XCTRL4A);
  		CMOS_WRITE(reg_a & ~DS_REGA_DV0, RTC_REG_A);
  		return;
  	}
  	CMOS_WRITE(reg_a & ~DS_REGA_DV0, RTC_REG_A);
  
  	if (has_panicked)
  		ip32_machine_restart(NULL);
  
  	enable_irq(MACEISA_RTC_IRQ);
  }
  
  static inline void ip32_power_button(void)
  {
  	if (has_panicked)
  		return;
  
  	if (shuting_down || kill_cad_pid(SIGINT, 1)) {
  		/* No init process or button pressed twice.  */
  		ip32_machine_power_off();
  	}
  
  	shuting_down = 1;
  	blink_timer.data = POWERDOWN_FREQ;
  	blink_timeout(POWERDOWN_FREQ);
  
  	init_timer(&power_timer);
  	power_timer.function = power_timeout;
  	power_timer.expires = jiffies + POWERDOWN_TIMEOUT * HZ;
  	add_timer(&power_timer);
  }
  
  static irqreturn_t ip32_rtc_int(int irq, void *dev_id)
  {
  	unsigned char reg_c;
  
  	reg_c = CMOS_READ(RTC_INTR_FLAGS);
  	if (!(reg_c & RTC_IRQF)) {
  		printk(KERN_WARNING
  			"%s: RTC IRQ without RTC_IRQF\n", __func__);
  	}
  	/* Wait until interrupt goes away */
  	disable_irq_nosync(MACEISA_RTC_IRQ);
  	init_timer(&debounce_timer);
  	debounce_timer.function = debounce;
  	debounce_timer.expires = jiffies + 50;
  	add_timer(&debounce_timer);
  
  	printk(KERN_DEBUG "Power button pressed\n");
  	ip32_power_button();
  	return IRQ_HANDLED;
  }
  
  static int panic_event(struct notifier_block *this, unsigned long event,
  		       void *ptr)
  {
  	unsigned long led;
  
  	if (has_panicked)
  		return NOTIFY_DONE;
  	has_panicked = 1;
  
  	/* turn off the green LED */
  	led = mace->perif.ctrl.misc | MACEISA_LED_GREEN;
  	mace->perif.ctrl.misc = led;
  
  	blink_timer.data = PANIC_FREQ;
  	blink_timeout(PANIC_FREQ);
  
  	return NOTIFY_DONE;
  }
  
  static struct notifier_block panic_block = {
  	.notifier_call = panic_event,
  };
  
  static __init int ip32_reboot_setup(void)
  {
  	/* turn on the green led only */
  	unsigned long led = mace->perif.ctrl.misc;
  	led |= MACEISA_LED_RED;
  	led &= ~MACEISA_LED_GREEN;
  	mace->perif.ctrl.misc = led;
  
  	_machine_restart = ip32_machine_restart;
  	_machine_halt = ip32_machine_halt;
  	pm_power_off = ip32_machine_power_off;
  
  	init_timer(&blink_timer);
  	blink_timer.function = blink_timeout;
  	atomic_notifier_chain_register(&panic_notifier_list, &panic_block);
  
  	if (request_irq(MACEISA_RTC_IRQ, ip32_rtc_int, 0, "rtc", NULL))
  		panic("Can't allocate MACEISA RTC IRQ");
  
  	return 0;
  }
  
  subsys_initcall(ip32_reboot_setup);
  