patch-2.0.32 linux/arch/i386/kernel/time.c

• Lines: 58
• Date: Fri Nov 7 10:06:21 1997
• Orig file: v2.0.31/linux/arch/i386/kernel/time.c
• Orig date: Sun Nov 10 09:40:53 1996

diff -u --recursive --new-file v2.0.31/linux/arch/i386/kernel/time.c linux/arch/i386/kernel/time.c
@@ -12,6 +12,8 @@
  *      precision CMOS clock update
  * 1996-05-03    Ingo Molnar
  *      fixed time warps in do_[slow|fast]_gettimeoffset()
+ * 1997-09-10	Updated NTP code according to technical memorandum Jan '96
+ *		"A Kernel Model for Precision Timekeeping" by Dave Mills
  */
 #include <linux/errno.h>
 #include <linux/sched.h>
@@ -269,9 +271,11 @@
 	}
 
 	xtime = *tv;
-	time_state = TIME_BAD;
-	time_maxerror = MAXPHASE;
-	time_esterror = MAXPHASE;
+	time_adjust = 0;		/* stop active adjtime() */
+	time_status |= STA_UNSYNC;
+	time_state = TIME_ERROR;	/* p. 24, (a) */
+	time_maxerror = NTP_PHASE_LIMIT;
+	time_esterror = NTP_PHASE_LIMIT;
 	sti();
 }
 
@@ -282,6 +286,9 @@
  * nowtime is written into the registers of the CMOS clock, it will
  * jump to the next second precisely 500 ms later. Check the Motorola
  * MC146818A or Dallas DS12887 data sheet for details.
+ *
+ * BUG: This routine does not handle hour overflow properly; it just
+ *      sets the minutes. Usually you'll only notice that after reboot!
  */
 static int set_rtc_mmss(unsigned long nowtime)
 {
@@ -318,8 +325,12 @@
 		}
 		CMOS_WRITE(real_seconds,RTC_SECONDS);
 		CMOS_WRITE(real_minutes,RTC_MINUTES);
-	} else
+	} else {
+		printk(KERN_WARNING
+		       "set_rtc_mmss: can't update from %d to %d\n",
+		       cmos_minutes, real_minutes);
 		retval = -1;
+	}
 
 	/* The following flags have to be released exactly in this order,
 	 * otherwise the DS12887 (popular MC146818A clone with integrated
@@ -350,7 +361,8 @@
 	 * CMOS clock accordingly every ~11 minutes. Set_rtc_mmss() has to be
 	 * called as close as possible to 500 ms before the new second starts.
 	 */
-	if (time_state != TIME_BAD && xtime.tv_sec > last_rtc_update + 660 &&
+	if ((time_status & STA_UNSYNC) == 0 &&
+	    xtime.tv_sec > last_rtc_update + 660 &&
 	    xtime.tv_usec > 500000 - (tick >> 1) &&
 	    xtime.tv_usec < 500000 + (tick >> 1))
 	  if (set_rtc_mmss(xtime.tv_sec) == 0)