patch-2.4.19 linux-2.4.19/arch/ppc64/kernel/rtc.c

• Lines: 383
• Date: Fri Aug 2 17:39:43 2002
• Orig file: linux-2.4.18/arch/ppc64/kernel/rtc.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -urN linux-2.4.18/arch/ppc64/kernel/rtc.c linux-2.4.19/arch/ppc64/kernel/rtc.c
@@ -0,0 +1,382 @@
+/*
+ *	Real Time Clock interface for PPC64.
+ *
+ *	Based on rtc.c by Paul Gortmaker
+ *
+ *	This driver allows use of the real time clock
+ *	from user space. It exports the /dev/rtc
+ *	interface supporting various ioctl() and also the
+ *	/proc/driver/rtc pseudo-file for status information.
+ *
+ * 	Interface does not support RTC interrupts nor an alarm.
+ *
+ *	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.
+ *
+ *      1.0	Mike Corrigan:    IBM iSeries rtc support
+ *      1.1	Dave Engebretsen: IBM pSeries rtc support
+ */
+
+#define RTC_VERSION		"1.1"
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/miscdevice.h>
+#include <linux/ioport.h>
+#include <linux/fcntl.h>
+#include <linux/mc146818rtc.h>
+#include <linux/init.h>
+#include <linux/poll.h>
+#include <linux/proc_fs.h>
+#include <linux/spinlock.h>
+
+#include <asm/io.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <asm/time.h>
+
+#include <asm/iSeries/LparData.h>
+#include <asm/iSeries/mf.h>
+#include <asm/machdep.h>
+#include <asm/iSeries/ItSpCommArea.h>
+
+extern int piranha_simulator;
+
+/*
+ *	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 loff_t rtc_llseek(struct file *file, loff_t offset, int origin);
+
+static ssize_t rtc_read(struct file *file, char *buf,
+			size_t count, loff_t *ppos);
+
+static int rtc_ioctl(struct inode *inode, struct file *file,
+		     unsigned int cmd, unsigned long arg);
+
+static int rtc_read_proc(char *page, char **start, off_t off,
+                         int count, int *eof, void *data);
+
+/*
+ *	If this driver ever becomes modularised, it will be really nice
+ *	to make the epoch retain its value across module reload...
+ */
+
+static unsigned long epoch = 1900;	/* year corresponding to 0x00	*/
+
+static const unsigned char days_in_mo[] = 
+{0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
+
+/*
+ *	Now all the various file operations that we export.
+ */
+
+static loff_t rtc_llseek(struct file *file, loff_t offset, int origin)
+{
+	return -ESPIPE;
+}
+
+static ssize_t rtc_read(struct file *file, char *buf,
+			size_t count, loff_t *ppos)
+{
+	return -EIO;
+}
+
+static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
+		     unsigned long arg)
+{
+	struct rtc_time wtime; 
+
+	switch (cmd) {
+	case RTC_RD_TIME:	/* Read the time/date from RTC	*/
+	{
+		ppc_md.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 int yrs;
+
+		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;
+		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 < 70)
+			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 > 169 )
+			return -EINVAL;
+
+		ppc_md.set_rtc_time(&rtc_tm);
+		
+		return 0;
+	}
+	case RTC_EPOCH_READ:	/* Read the epoch.	*/
+	{
+		return put_user (epoch, (unsigned long *)arg);
+	}
+	case RTC_EPOCH_SET:	/* Set the epoch.	*/
+	{
+		/* 
+		 * There were no RTC clocks before 1900.
+		 */
+		if (arg < 1900)
+			return -EINVAL;
+
+		if (!capable(CAP_SYS_TIME))
+			return -EACCES;
+
+		epoch = arg;
+		return 0;
+	}
+	default:
+		return -EINVAL;
+	}
+	return copy_to_user((void *)arg, &wtime, sizeof wtime) ? -EFAULT : 0;
+}
+
+static int rtc_open(struct inode *inode, struct file *file)
+{
+	return 0;
+}
+
+static int rtc_release(struct inode *inode, struct file *file)
+{
+	return 0;
+}
+
+/*
+ *	The various file operations we support.
+ */
+static struct file_operations rtc_fops = {
+	owner:		THIS_MODULE,
+	llseek:		rtc_llseek,
+	read:		rtc_read,
+	ioctl:		rtc_ioctl,
+	open:		rtc_open,
+	release:	rtc_release,
+};
+
+static struct miscdevice rtc_dev=
+{
+	RTC_MINOR,
+	"rtc",
+	&rtc_fops
+};
+
+static int __init rtc_init(void)
+{
+	misc_register(&rtc_dev);
+	create_proc_read_entry ("driver/rtc", 0, 0, rtc_read_proc, NULL);
+
+	printk(KERN_INFO "i/pSeries Real Time Clock Driver v" RTC_VERSION "\n");
+
+	return 0;
+}
+
+static void __exit rtc_exit (void)
+{
+	remove_proc_entry ("driver/rtc", NULL);
+	misc_deregister(&rtc_dev);
+}
+
+module_init(rtc_init);
+module_exit(rtc_exit);
+EXPORT_NO_SYMBOLS;
+
+/*
+ *	Info exported via "/proc/driver/rtc".
+ */
+
+static int rtc_proc_output (char *buf)
+{
+	
+	char *p;
+	struct rtc_time tm;
+	
+	p = buf;
+
+	ppc_md.get_rtc_time(&tm);
+
+	/*
+	 * There is no way to tell if the luser has the RTC set for local
+	 * time or for Universal Standard Time (GMT). Probably local though.
+	 */
+	p += sprintf(p,
+		     "rtc_time\t: %02d:%02d:%02d\n"
+		     "rtc_date\t: %04d-%02d-%02d\n"
+	 	     "rtc_epoch\t: %04lu\n",
+		     tm.tm_hour, tm.tm_min, tm.tm_sec,
+		     tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, epoch);
+
+	p += sprintf(p,
+		     "DST_enable\t: no\n"
+		     "BCD\t\t: yes\n"
+		     "24hr\t\t: yes\n" );
+
+	return  p - buf;
+}
+
+static int rtc_read_proc(char *page, char **start, off_t off,
+                         int count, int *eof, void *data)
+{
+        int len = rtc_proc_output (page);
+        if (len <= off+count) *eof = 1;
+        *start = page + off;
+        len -= off;
+        if (len>count) len = count;
+        if (len<0) len = 0;
+        return len;
+}
+
+/*
+ * Get the RTC from the virtual service processor
+ * This requires flowing LpEvents to the primary partition
+ */
+void iSeries_get_rtc_time(struct rtc_time *rtc_tm)
+{
+	if (piranha_simulator)
+		return;
+
+	mf_getRtc(rtc_tm);
+	rtc_tm->tm_mon--;
+}
+
+
+void pSeries_get_rtc_time(struct rtc_time *rtc_tm)
+{
+        unsigned long ret[8];
+        int error;
+	int count;
+
+	/*
+	 * error -2 is clock busy, we keep retrying a few times to see
+	 * if it will come good  -- paulus
+	 */
+	count = 0;
+	do {
+		error = rtas_call(rtas_token("get-time-of-day"), 0, 8, (void *)&ret);
+	} while (error == -2 && ++count < 1000);
+
+        if (error != 0) {
+                printk(KERN_WARNING "error: reading the clock failed (%d)\n",
+		       error);
+		return;
+        }
+
+	rtc_tm->tm_sec = ret[5];
+	rtc_tm->tm_min = ret[4];
+	rtc_tm->tm_hour = ret[3];
+	rtc_tm->tm_mday = ret[2];
+	rtc_tm->tm_mon = ret[1] - 1;
+	rtc_tm->tm_year = ret[0] - 1900;
+}
+
+int pSeries_set_rtc_time(struct rtc_time *tm)
+{
+        int error;
+	int count;
+
+	/*
+	 * error -2 is clock busy, we keep retrying a few times to see
+	 * if it will come good  -- paulus
+	 */
+	count = 0;
+	do {
+	        error = rtas_call(rtas_token("set-time-of-day"), 7, 1, NULL,
+				  tm->tm_year + 1900, tm->tm_mon + 1, 
+				  tm->tm_mday, tm->tm_hour, tm->tm_min, 
+				  tm->tm_sec, 0);
+	} while (error == -2 && ++count < 1000);
+
+        if (error != 0)
+                printk(KERN_WARNING "error: setting the clock failed (%d)\n",
+		       error); 
+
+        return 0;
+}
+
+/*
+ * Set the RTC in the virtual service processor
+ * This requires flowing LpEvents to the primary partition
+ */
+int iSeries_set_rtc_time(struct rtc_time *tm)
+{
+	mf_setRtc(tm);
+	return 0;
+}
+
+void iSeries_get_boot_time(struct rtc_time *tm)
+{
+	unsigned long time;
+	static unsigned long lastsec = 1;
+
+	u32 dataWord1 = *((u32 *)(&xSpCommArea.xBcdTimeAtIplStart));
+	u32 dataWord2 = *(((u32 *)&(xSpCommArea.xBcdTimeAtIplStart)) + 1);
+	int year = 1970;
+	int year1 = ( dataWord1 >> 24 ) & 0x000000FF;
+	int year2 = ( dataWord1 >> 16 ) & 0x000000FF;
+	int sec = ( dataWord1 >> 8 ) & 0x000000FF;
+	int min = dataWord1 & 0x000000FF;
+	int hour = ( dataWord2 >> 24 ) & 0x000000FF;
+	int day = ( dataWord2 >> 8 ) & 0x000000FF;
+	int mon = dataWord2 & 0x000000FF;
+
+	if ( piranha_simulator )
+		return;
+
+	BCD_TO_BIN(sec);
+	BCD_TO_BIN(min);
+	BCD_TO_BIN(hour);
+	BCD_TO_BIN(day);
+	BCD_TO_BIN(mon);
+	BCD_TO_BIN(year1);
+	BCD_TO_BIN(year2);
+	year = year1 * 100 + year2;
+
+	time = mktime(year, mon, day, hour, min, sec);
+	time += ( jiffies / HZ );
+
+	/* Now THIS is a nasty hack!
+	* It ensures that the first two calls get different answers.  
+	* That way the loop in init_time (time.c) will not think
+	* the clock is stuck.
+	*/
+	if ( lastsec ) {
+		time -= lastsec;
+		--lastsec;
+	}
+
+	to_tm(time, tm); 
+	tm->tm_year -= 1900;
+	tm->tm_mon  -= 1;
+}