On attach check if clock is running, mark it invalid if not. Return

error from gettime method if clock is not valid.  Mark clock as valid
on settime.

Report more debugging info.

sys/arch/sh3/dev/rtc.c

@@ -35,7 +35,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: rtc.c,v 1.1 2006/09/20 00:41:11 uwe Exp $");
+__KERNEL_RCSID(0, "$NetBSD: rtc.c,v 1.2 2007/03/30 00:32:58 uwe Exp $");
 
 #include <sys/param.h>
 #include <sys/kernel.h>
@@ -50,10 +50,15 @@ __KERNEL_RCSID(0, "$NetBSD: rtc.c,v 1.1 2006/09/20 00:41:11 uwe Exp $");
 
 #include <sh3/rtcreg.h>
 
+#if defined(DEBUG) && !defined(RTC_DEBUG)
+#define RTC_DEBUG
+#endif
+
 
 struct rtc_softc {
 	struct device sc_dev;
 
+	int sc_valid;
 	struct todr_chip_handle sc_todr;
 };
 
@@ -82,41 +87,67 @@ static void
 rtc_attach(struct device *parent, struct device *self, void *aux)
 {
 	struct rtc_softc *sc = (void *)self;
+	uint8_t r;
+#ifdef RTC_DEBUG
+	char bits[128];
+#endif
 
 	printf("\n");
 
-	/* Make sure RTC is started */
+	r = _reg_read_1(SH_(RCR2));
-	_reg_write_1(SH_(RCR2), SH_RCR2_ENABLE | SH_RCR2_START);
 
 #ifdef RTC_DEBUG
-	{
+	printf("%s: RCR2=%s\n", sc->sc_dev.dv_xname,
-		struct clock_ymdhms dt;
+	       bitmask_snprintf(r, SH_RCR2_BITS, bits, sizeof(bits)));
-		int error;
-
-		error = rtc_gettime_ymdhms(NULL, &dt);
-		if (error)
-			printf("%s: error %d\n", sc->sc_dev.dv_xname, error);
-		else
-			printf("%s: %04d-%02d-%02d %02d:%02d:%02d\n",
-			       sc->sc_dev.dv_xname,
-			       dt.dt_year, dt.dt_mon, dt.dt_day,
-			       dt.dt_hour, dt.dt_min, dt.dt_sec);
-	}
 #endif
+
+	/* Was the clock running? */
+	if ((r & (SH_RCR2_ENABLE | SH_RCR2_START)) == (SH_RCR2_ENABLE
+						       | SH_RCR2_START))
+		sc->sc_valid = 1;
+	else {
+		sc->sc_valid = 0;
+		printf("%s: WARNING: clock was stopped\n",
+		       sc->sc_dev.dv_xname);
+	}
+
+	/* Disable carry and alarm interrupts */
+	_reg_write_1(SH_(RCR1), 0);
+
+	/* Clock runs, no periodic interrupts, no 30-sec adjustment */
+	_reg_write_1(SH_(RCR2), SH_RCR2_ENABLE | SH_RCR2_START);
+
 	sc->sc_todr.cookie = sc;
 	sc->sc_todr.todr_gettime_ymdhms = rtc_gettime_ymdhms;
 	sc->sc_todr.todr_settime_ymdhms = rtc_settime_ymdhms;
 
 	todr_attach(&sc->sc_todr);
+
+#ifdef RTC_DEBUG
+	{
+		struct clock_ymdhms dt;
+		rtc_gettime_ymdhms(&sc->sc_todr, &dt);
+	}
+#endif
 }
 
 
 static int
 rtc_gettime_ymdhms(todr_chip_handle_t h, struct clock_ymdhms *dt)
 {
+	struct rtc_softc *sc = h->cookie;
 	unsigned int year;
 	int retry = 8;
 
+	if (!sc->sc_valid) {
+#ifdef RTC_DEBUG
+		printf("RTC: gettime: not valid\n");
+		/* but proceed and read/print it anyway */
+#else
+		return EIO;
+#endif
+	}
+
 	/* disable carry interrupt */
 	_reg_bclr_1(SH_(RCR1), SH_RCR1_CIE);
 
@@ -145,13 +176,26 @@ rtc_gettime_ymdhms(todr_chip_handle_t h, struct clock_ymdhms *dt)
 #undef RTCGET
 	} while ((_reg_read_1(SH_(RCR1)) & SH_RCR1_CF) && --retry > 0);
 
-	if (retry == 0)
+	if (retry == 0) {
+#ifdef RTC_DEBUG
+		printf("RTC: gettime: retry failed\n");
+#endif
 		return EIO;
+	}
 
 	dt->dt_year += 1900;
 	if (dt->dt_year < POSIX_BASE_YEAR)
 		dt->dt_year += 100;
 
+#ifdef RTC_DEBUG
+	printf("RTC: gettime: %04d-%02d-%02d %02d:%02d:%02d\n",
+	       dt->dt_year, dt->dt_mon, dt->dt_day,
+	       dt->dt_hour, dt->dt_min, dt->dt_sec);
+
+	if (!sc->sc_valid)
+		return EIO;
+#endif
+
 	return 0;
 }
 
@@ -159,16 +203,16 @@ rtc_gettime_ymdhms(todr_chip_handle_t h, struct clock_ymdhms *dt)
 static int
 rtc_settime_ymdhms(todr_chip_handle_t h, struct clock_ymdhms *dt)
 {
+	struct rtc_softc *sc = h->cookie;
 	unsigned int year;
 	uint8_t r;
 
 	year = TOBCD(dt->dt_year % 100);
 
-	/* stop clock */
 	r = _reg_read_1(SH_(RCR2));
-	r |= SH_RCR2_RESET;
+
-	r &= ~SH_RCR2_START;
+	/* stop clock */
-	_reg_write_1(SH_(RCR2), r);
+	_reg_write_1(SH_(RCR2), (r & ~SH_RCR2_START) | SH_RCR2_RESET);
 
 	/* set time */
 	if (CPU_IS_SH3)
@@ -189,7 +233,14 @@ rtc_settime_ymdhms(todr_chip_handle_t h, struct clock_ymdhms *dt)
 #undef RTCSET
 
 	/* start clock */
-	_reg_write_1(SH_(RCR2), r | SH_RCR2_START);
+	_reg_write_1(SH_(RCR2), r);
+	sc->sc_valid = 1;
+
+#ifdef RTC_DEBUG
+	printf("RTC: settime: %04d-%02d-%02d %02d:%02d:%02d\n",
+	       dt->dt_year, dt->dt_mon, dt->dt_day,
+	       dt->dt_hour, dt->dt_min, dt->dt_sec);
+#endif
 
 	return 0;
 }