o Support for the front panel on the Indy. The panel work now as a

   user would expect it to work, like under IRIX with the exception
   that the machine doesn't freeze solid as long as the button is
   pressed.
 o Realtime clock driver (CONFIG_SGI_DS1286) for the Indy.  Includes
   /proc/rtc interface which tells you everything about your RTC which
   you never wanted to know.  You have to configure this driver into
   your kernel or you won't be able to set your RTC.
 o Some cleanup of the RTC interfaces in Linux, RTC does no longer mean
   PC-style RTC.  The userland interface definitions are now in
   <linux/rtc.h>.  We still need some more cleanup until we can enable
   several RTC drivers.
 o Virtual aliasing fixes for ptrace(2).
 o Add ptrace(2) interface definitions needed to build GDB to
   <asm/ptrace.h>.
 o Revert to some older routines, the newer optimized ones are buggy.
 o On panic the Indy LED will be blinking fast crying to the admin
   passing by [music from Rocky Horror show] ``fix me, fix me, fix
   me''.
 o On panic the power button will only reboot the machine, not power it
   down.  That's probably more what people want it to do.
 o Remove some old files.
 o Did I tell you that CVS is buggy?

3 files changed, 575 insertions, 0 deletions

diff --git a/drivers/sgi/char/Config.in b/drivers/sgi/char/Config.in
index e216e4328..d3aece75d 100644
--- a/drivers/sgi/char/Config.in
+++ b/drivers/sgi/char/Config.in
@@ -9,4 +9,6 @@ if [ "$CONFIG_SGI_SERIAL" != "n" ]; then
   define_bool CONFIG_SERIAL y
 fi
 
+bool 'SGI DS1286  RTC support' CONFIG_SGI_DS1286
+
 endmenu
diff --git a/drivers/sgi/char/Makefile b/drivers/sgi/char/Makefile
index 7032c700c..5616d03a5 100644
--- a/drivers/sgi/char/Makefile
+++ b/drivers/sgi/char/Makefile
@@ -15,4 +15,8 @@ ifeq ($(CONFIG_SGI_SERIAL),y)
   O_OBJS += sgiserial.o
 endif
 
+ifeq ($(CONFIG_SGI_DS1286),y)
+  O_OBJS += ds1286.o
+endif
+
 include $(TOPDIR)/Rules.make
diff --git a/drivers/sgi/char/ds1286.c b/drivers/sgi/char/ds1286.c
new file mode 100644
index 000000000..0d3f7a005
--- /dev/null
+++ b/drivers/sgi/char/ds1286.c
@@ -0,0 +1,569 @@
+/* $Id: ds1286.c,v 1.1 1998/07/09 20:01:29 ralf Exp $
+ *
+ *	Real Time Clock interface for Linux	
+ *
+ *	Copyright (C) 1998 Ralf Baechle
+ *	
+ *	Based on code written by Paul Gortmaker.
+ *
+ *	This driver allows use of the real time clock (built into
+ *	nearly all computers) from user space. It exports the /dev/rtc
+ *	interface supporting various ioctl() and also the /proc/rtc
+ *	pseudo-file for status information.
+ *
+ *	The ioctls can be used to set the interrupt behaviour and
+ *	generation rate from the RTC via IRQ 8. Then the /dev/rtc
+ *	interface can be used to make use of these timer interrupts,
+ *	be they interval or alarm based.
+ *
+ *	The /dev/rtc interface will block on reads until an interrupt
+ *	has been received. If a RTC interrupt has already happened,
+ *	it will output an unsigned long and then block. The output value
+ *	contains the interrupt status in the low byte and the number of
+ *	interrupts since the last read in the remaining high bytes. The 
+ *	/dev/rtc interface can also be used with the select(2) call.
+ *
+ *	This program is free software; you can redistribute it and/or
+ *	modify it under the terms of the GNU General Public License
+ *	as published by the Free Software Foundation; either version
+ *	2 of the License, or (at your option) any later version.
+ */
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/miscdevice.h>
+#include <linux/malloc.h>
+#include <linux/ioport.h>
+#include <linux/fcntl.h>
+#include <linux/init.h>
+#include <linux/poll.h>
+#include <linux/rtc.h>
+
+#include <asm/ds1286.h>
+#include <asm/io.h>
+#include <asm/uaccess.h>
+#include <asm/spinlock.h>
+#include <asm/system.h>
+
+#define DS1286_VERSION		"1.0"
+
+/*
+ *	We sponge a minor off of the misc major. No need slurping
+ *	up another valuable major dev number for this. If you add
+ *	an ioctl, make sure you don't conflict with SPARC's RTC
+ *	ioctls.
+ */
+
+static struct wait_queue *ds1286_wait;
+
+static long long ds1286_llseek(struct file *file, loff_t offset, int origin);
+
+static ssize_t ds1286_read(struct file *file, char *buf,
+			size_t count, loff_t *ppos);
+
+static int ds1286_ioctl(struct inode *inode, struct file *file,
+                        unsigned int cmd, unsigned long arg);
+
+static unsigned int ds1286_poll(struct file *file, poll_table *wait);
+
+void get_rtc_time (struct rtc_time *rtc_tm);
+void get_rtc_alm_time (struct rtc_time *alm_tm);
+
+void set_rtc_irq_bit(unsigned char bit);
+void clear_rtc_irq_bit(unsigned char bit);
+
+static inline unsigned char ds1286_is_updating(void);
+
+#ifdef __SMP__
+static spinlock_t ds1286_lock = SPIN_LOCK_UNLOCKED;
+#endif
+
+/*
+ *	Bits in rtc_status. (7 bits of room for future expansion)
+ */
+
+#define RTC_IS_OPEN		0x01	/* means /dev/rtc is in use	*/
+#define RTC_TIMER_ON		0x02	/* missed irq timer active	*/
+
+unsigned char ds1286_status = 0;	/* bitmapped status byte.	*/
+unsigned long ds1286_freq = 0;		/* Current periodic IRQ rate	*/
+unsigned long ds1286_irq_data = 0;	/* our output to the world	*/
+
+unsigned char days_in_mo[] = 
+{0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
+
+/*
+ *	A very tiny interrupt handler. It runs with SA_INTERRUPT set,
+ *	so that there is no possibility of conflicting with the
+ *	set_rtc_mmss() call that happens during some timer interrupts.
+ *	(See ./arch/XXXX/kernel/time.c for the set_rtc_mmss() function.)
+ */
+
+/*
+ *	Now all the various file operations that we export.
+ */
+
+static long long ds1286_llseek(struct file *file, loff_t offset, int origin)
+{
+	return -ESPIPE;
+}
+
+static ssize_t ds1286_read(struct file *file, char *buf,
+                           size_t count, loff_t *ppos)
+{
+	struct wait_queue wait = { current, NULL };
+	unsigned long data;
+	ssize_t retval;
+	
+	if (count < sizeof(unsigned long))
+		return -EINVAL;
+
+	add_wait_queue(&ds1286_wait, &wait);
+
+	current->state = TASK_INTERRUPTIBLE;
+		
+	while ((data = xchg(&ds1286_irq_data, 0)) == 0) {
+		if (file->f_flags & O_NONBLOCK) {
+			retval = -EAGAIN;
+			goto out;
+		}
+		if (signal_pending(current)) {
+			retval = -ERESTARTSYS;
+			goto out;
+		}
+		schedule();
+	}
+
+	retval = put_user(data, (unsigned long *)buf); 
+	if (!retval)
+		retval = sizeof(unsigned long); 
+ out:
+	current->state = TASK_RUNNING;
+	remove_wait_queue(&ds1286_wait, &wait);
+
+	return retval;
+}
+
+static int ds1286_ioctl(struct inode *inode, struct file *file,
+                        unsigned int cmd, unsigned long arg)
+{
+
+	struct rtc_time wtime; 
+
+	switch (cmd) {
+	case RTC_AIE_OFF:	/* Mask alarm int. enab. bit	*/
+	{
+		unsigned int flags;
+		unsigned char val;
+
+		if (!capable(CAP_SYS_TIME))
+			return -EACCES;
+
+		spin_lock_irqsave(&ds1286_lock, flags);
+		val = CMOS_READ(RTC_CMD);
+		val |=  RTC_TDM;
+		CMOS_WRITE(val, RTC_CMD);
+		spin_unlock_irqrestore(&ds1286_lock, flags);
+
+		return 0;
+	}
+	case RTC_AIE_ON:	/* Allow alarm interrupts.	*/
+	{
+		unsigned int flags;
+		unsigned char val;
+
+		if (!capable(CAP_SYS_TIME))
+			return -EACCES;
+
+		spin_lock_irqsave(&ds1286_lock, flags);
+		val = CMOS_READ(RTC_CMD);
+		val &=  ~RTC_TDM;
+		CMOS_WRITE(val, RTC_CMD);
+		spin_unlock_irqrestore(&ds1286_lock, flags);
+
+		return 0;
+	}
+	case RTC_WIE_OFF:	/* Mask watchdog int. enab. bit	*/
+	{
+		unsigned int flags;
+		unsigned char val;
+
+		if (!capable(CAP_SYS_TIME))
+			return -EACCES;
+
+		spin_lock_irqsave(&ds1286_lock, flags);
+		val = CMOS_READ(RTC_CMD);
+		val |= RTC_WAM;
+		CMOS_WRITE(val, RTC_CMD);
+		spin_unlock_irqrestore(&ds1286_lock, flags);
+
+		return 0;
+	}
+	case RTC_WIE_ON:	/* Allow watchdog interrupts.	*/
+	{
+		unsigned int flags;
+		unsigned char val;
+
+		if (!capable(CAP_SYS_TIME))
+			return -EACCES;
+
+		spin_lock_irqsave(&ds1286_lock, flags);
+		val = CMOS_READ(RTC_CMD);
+		val &= ~RTC_WAM;
+		CMOS_WRITE(val, RTC_CMD);
+		spin_unlock_irqrestore(&ds1286_lock, flags);
+
+		return 0;
+	}
+	case RTC_ALM_READ:	/* Read the present alarm time */
+	{
+		/*
+		 * This returns a struct rtc_time. Reading >= 0xc0
+		 * means "don't care" or "match all". Only the tm_hour,
+		 * tm_min, and tm_sec values are filled in.
+		 */
+
+		get_rtc_alm_time(&wtime);
+		break; 
+	}
+	case RTC_ALM_SET:	/* Store a time into the alarm */
+	{
+		/*
+		 * This expects a struct rtc_time. Writing 0xff means
+		 * "don't care" or "match all". Only the tm_hour,
+		 * tm_min and tm_sec are used.
+		 */
+		unsigned char hrs, min, sec;
+		struct rtc_time alm_tm;
+
+		if (!capable(CAP_SYS_TIME))
+			return -EACCES;
+
+		if (copy_from_user(&alm_tm, (struct rtc_time*)arg,
+				   sizeof(struct rtc_time)))
+			return -EFAULT;
+
+		hrs = alm_tm.tm_hour;
+		min = alm_tm.tm_min;
+
+		if (hrs >= 24)
+			hrs = 0xff;
+
+		if (min >= 60)
+			min = 0xff;
+
+		BIN_TO_BCD(sec);
+		BIN_TO_BCD(min);
+		BIN_TO_BCD(hrs);
+
+		spin_lock(&ds1286_lock);
+		CMOS_WRITE(hrs, RTC_HOURS_ALARM);
+		CMOS_WRITE(min, RTC_MINUTES_ALARM);
+		spin_unlock(&ds1286_lock);
+
+		return 0;
+	}
+	case RTC_RD_TIME:	/* Read the time/date from RTC	*/
+	{
+		get_rtc_time(&wtime);
+		break;
+	}
+	case RTC_SET_TIME:	/* Set the RTC */
+	{
+		struct rtc_time rtc_tm;
+		unsigned char mon, day, hrs, min, sec, leap_yr;
+		unsigned char save_control;
+		unsigned int yrs, flags;
+
+		if (!capable(CAP_SYS_TIME))
+			return -EACCES;
+
+		if (copy_from_user(&rtc_tm, (struct rtc_time*)arg,
+				   sizeof(struct rtc_time)))
+			return -EFAULT;
+
+		yrs = rtc_tm.tm_year + 1900;
+		mon = rtc_tm.tm_mon + 1;   /* tm_mon starts at zero */
+		day = rtc_tm.tm_mday;
+		hrs = rtc_tm.tm_hour;
+		min = rtc_tm.tm_min;
+		sec = rtc_tm.tm_sec;
+
+		if (yrs < 1970)
+			return -EINVAL;
+
+		leap_yr = ((!(yrs % 4) && (yrs % 100)) || !(yrs % 400));
+
+		if ((mon > 12) || (day == 0))
+			return -EINVAL;
+
+		if (day > (days_in_mo[mon] + ((mon == 2) && leap_yr)))
+			return -EINVAL;
+
+		if ((hrs >= 24) || (min >= 60) || (sec >= 60))
+			return -EINVAL;
+
+		if ((yrs -= 1940) > 255)    /* They are unsigned */
+			return -EINVAL;
+
+		if (yrs >= 100)
+			yrs -= 100;
+
+		BIN_TO_BCD(sec);
+		BIN_TO_BCD(min);
+		BIN_TO_BCD(hrs);
+		BIN_TO_BCD(day);
+		BIN_TO_BCD(mon);
+		BIN_TO_BCD(yrs);
+
+		spin_lock_irqsave(&ds1286_lock, flags);
+		save_control = CMOS_READ(RTC_CMD);
+		CMOS_WRITE((save_control|RTC_TE), RTC_CMD);
+
+		CMOS_WRITE(yrs, RTC_YEAR);
+		CMOS_WRITE(mon, RTC_MONTH);
+		CMOS_WRITE(day, RTC_DATE);
+		CMOS_WRITE(hrs, RTC_HOURS);
+		CMOS_WRITE(min, RTC_MINUTES);
+		CMOS_WRITE(sec, RTC_SECONDS);
+		CMOS_WRITE(0, RTC_HUNDREDTH_SECOND);
+
+		CMOS_WRITE(save_control, RTC_CMD);
+		spin_unlock_irqrestore(&ds1286_lock, flags);
+
+		return 0;
+	}
+	default:
+		return -EINVAL;
+	}
+	return copy_to_user((void *)arg, &wtime, sizeof wtime) ? -EFAULT : 0;
+}
+
+/*
+ *	We enforce only one user at a time here with the open/close.
+ *	Also clear the previous interrupt data on an open, and clean
+ *	up things on a close.
+ */
+
+static int ds1286_open(struct inode *inode, struct file *file)
+{
+	if(ds1286_status & RTC_IS_OPEN)
+		return -EBUSY;
+
+	ds1286_status |= RTC_IS_OPEN;
+	ds1286_irq_data = 0;
+	return 0;
+}
+
+static int ds1286_release(struct inode *inode, struct file *file)
+{
+	ds1286_status &= ~RTC_IS_OPEN;
+	return 0;
+}
+
+static unsigned int ds1286_poll(struct file *file, poll_table *wait)
+{
+	poll_wait(file, &ds1286_wait, wait);
+	if (ds1286_irq_data != 0)
+		return POLLIN | POLLRDNORM;
+	return 0;
+}
+
+/*
+ *	The various file operations we support.
+ */
+
+static struct file_operations ds1286_fops = {
+	ds1286_llseek,
+	ds1286_read,
+	NULL,		/* No write */
+	NULL,		/* No readdir */
+	ds1286_poll,
+	ds1286_ioctl,
+	NULL,		/* No mmap */
+	ds1286_open,
+	ds1286_release
+};
+
+static struct miscdevice ds1286_dev=
+{
+	RTC_MINOR,
+	"rtc",
+	&ds1286_fops
+};
+
+__initfunc(int ds1286_init(void))
+{
+	printk(KERN_INFO "DS1286 Real Time Clock Driver v%s\n", DS1286_VERSION);
+	misc_register(&ds1286_dev);
+
+	ds1286_wait = NULL;
+
+	return 0;
+}
+
+static char *days[] = {
+	"***", "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
+};
+
+/*
+ *	Info exported via "/proc/rtc".
+ */
+int get_ds1286_status(char *buf)
+{
+	char *p, *s;
+	struct rtc_time tm;
+	unsigned char hundredth, month, cmd, amode;
+
+	p = buf;
+
+	get_rtc_time(&tm);
+	hundredth = CMOS_READ(RTC_HUNDREDTH_SECOND);
+	hundredth = BCD_TO_BIN(hundredth);
+
+	p += sprintf(p,
+	             "rtc_time\t: %02d:%02d:%02d.%02d\n"
+	             "rtc_date\t: %04d-%02d-%02d\n",
+		     tm.tm_hour, tm.tm_min, tm.tm_sec, hundredth,
+		     tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday);
+
+	/*
+	 * We implicitly assume 24hr mode here. Alarm values >= 0xc0 will
+	 * match any value for that particular field. Values that are
+	 * greater than a valid time, but less than 0xc0 shouldn't appear.
+	 */
+	get_rtc_alm_time(&tm);
+	p += sprintf(p, "alarm\t\t: %s ", days[tm.tm_wday]);
+	if (tm.tm_hour <= 24)
+		p += sprintf(p, "%02d:", tm.tm_hour);
+	else
+		p += sprintf(p, "**:");
+
+	if (tm.tm_min <= 59)
+		p += sprintf(p, "%02d\n", tm.tm_min);
+	else
+		p += sprintf(p, "**\n");
+
+	month = CMOS_READ(RTC_MONTH);
+	p += sprintf(p,
+	             "oscillator\t: %s\n"
+	             "square_wave\t: %s\n",
+	             (month & RTC_EOSC) ? "disabled" : "enabled",
+	             (month & RTC_ESQW) ? "disabled" : "enabled");
+
+	amode = ((CMOS_READ(RTC_MINUTES_ALARM) & 0x80) >> 5) |
+	        ((CMOS_READ(RTC_HOURS_ALARM) & 0x80) >> 6) |
+	        ((CMOS_READ(RTC_DAY_ALARM) & 0x80) >> 7);
+	if (amode == 7)      s = "each minute";
+	else if (amode == 3) s = "minutes match";
+	else if (amode == 1) s = "hours and minutes match";
+	else if (amode == 0) s = "days, hours and minutes match";
+	else                 s = "invalid";
+	p += sprintf(p, "alarm_mode\t: %s\n", s);
+
+	cmd = CMOS_READ(RTC_CMD);
+	p += sprintf(p,
+	             "alarm\t\t: %s\n"
+	             "wdog_alarm\t: %s\n"
+	             "alarm_mask\t: %s\n"
+	             "wdog_alarm_mask\t: %s\n"
+	             "interrupt_mode\t: %s\n"
+	             "INTB_mode\t: %s_active\n"
+	             "interrupt_pins\t: %s\n",
+		     (cmd & RTC_TDF) ? "yes" : "no",
+		     (cmd & RTC_WAF) ? "yes" : "no",
+		     (cmd & RTC_TDM) ? "disabled" : "enabled",
+		     (cmd & RTC_WAM) ? "disabled" : "enabled",
+		     (cmd & RTC_PU_LVL) ? "pulse" : "level",
+		     (cmd & RTC_IBH_LO) ? "low" : "high",
+	             (cmd & RTC_IPSW) ? "unswapped" : "swapped");
+
+	return  p - buf;
+}
+
+/*
+ * Returns true if a clock update is in progress
+ */
+static inline unsigned char ds1286_is_updating(void)
+{
+	return CMOS_READ(RTC_CMD) & RTC_TE;
+}
+
+void get_rtc_time(struct rtc_time *rtc_tm)
+{
+	unsigned long uip_watchdog = jiffies;
+	unsigned char save_control;
+	unsigned int flags;
+
+	/*
+	 * read RTC once any update in progress is done. The update
+	 * can take just over 2ms. We wait 10 to 20ms. There is no need to
+	 * to poll-wait (up to 1s - eeccch) for the falling edge of RTC_UIP.
+	 * If you need to know *exactly* when a second has started, enable
+	 * periodic update complete interrupts, (via ioctl) and then 
+	 * immediately read /dev/rtc which will block until you get the IRQ.
+	 * Once the read clears, read the RTC time (again via ioctl). Easy.
+	 */
+
+	if (ds1286_is_updating() != 0)
+		while (jiffies - uip_watchdog < 2*HZ/100)
+			barrier();
+
+	/*
+	 * Only the values that we read from the RTC are set. We leave
+	 * tm_wday, tm_yday and tm_isdst untouched. Even though the
+	 * RTC has RTC_DAY_OF_WEEK, we ignore it, as it is only updated
+	 * by the RTC when initially set to a non-zero value.
+	 */
+	spin_lock_irqsave(&ds1286_lock, flags);
+	save_control = CMOS_READ(RTC_CMD);
+	CMOS_WRITE((save_control|RTC_TE), RTC_CMD);
+
+	rtc_tm->tm_sec = CMOS_READ(RTC_SECONDS);
+	rtc_tm->tm_min = CMOS_READ(RTC_MINUTES);
+	rtc_tm->tm_hour = CMOS_READ(RTC_HOURS) & 0x1f;
+	rtc_tm->tm_mday = CMOS_READ(RTC_DATE);
+	rtc_tm->tm_mon = CMOS_READ(RTC_MONTH) & 0x1f;
+	rtc_tm->tm_year = CMOS_READ(RTC_YEAR);
+
+	CMOS_WRITE(save_control, RTC_CMD);
+	spin_unlock_irqrestore(&ds1286_lock, flags);
+
+	BCD_TO_BIN(rtc_tm->tm_sec);
+	BCD_TO_BIN(rtc_tm->tm_min);
+	BCD_TO_BIN(rtc_tm->tm_hour);
+	BCD_TO_BIN(rtc_tm->tm_mday);
+	BCD_TO_BIN(rtc_tm->tm_mon);
+	BCD_TO_BIN(rtc_tm->tm_year);
+
+	/*
+	 * Account for differences between how the RTC uses the values
+	 * and how they are defined in a struct rtc_time;
+	 */
+	if (rtc_tm->tm_year < 45)
+		rtc_tm->tm_year += 30;
+	if ((rtc_tm->tm_year += 40) < 70)
+		rtc_tm->tm_year += 100;
+
+	rtc_tm->tm_mon--;
+}
+
+void get_rtc_alm_time(struct rtc_time *alm_tm)
+{
+	unsigned char cmd;
+	unsigned int flags;
+
+	/*
+	 * Only the values that we read from the RTC are set. That
+	 * means only tm_wday, tm_hour, tm_min.
+	 */
+	spin_lock_irqsave(&ds1286_lock, flags);
+	alm_tm->tm_min = CMOS_READ(RTC_MINUTES_ALARM) & 0x7f;
+	alm_tm->tm_hour = CMOS_READ(RTC_HOURS_ALARM)  & 0x1f;
+	alm_tm->tm_wday = CMOS_READ(RTC_DAY_ALARM)    & 0x07;
+	cmd = CMOS_READ(RTC_CMD);
+	spin_unlock_irqrestore(&ds1286_lock, flags);
+
+	BCD_TO_BIN(alm_tm->tm_min);
+	BCD_TO_BIN(alm_tm->tm_hour);
+	alm_tm->tm_sec = 0;
+}