diff --git a/sys/amd64/amd64/machdep.c b/sys/amd64/amd64/machdep.c
index 9d26e53298c4..43fbfc324e67 100644
--- a/sys/amd64/amd64/machdep.c
+++ b/sys/amd64/amd64/machdep.c
@@ -61,7 +61,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/buf.h>
 #include <sys/bus.h>
 #include <sys/callout.h>
-#include <sys/clock.h>
 #include <sys/cons.h>
 #include <sys/cpu.h>
 #include <sys/eventhandler.h>
diff --git a/sys/amd64/include/clock.h b/sys/amd64/include/clock.h
index b7fafcf4ddac..de09de3f1fd4 100644
--- a/sys/amd64/include/clock.h
+++ b/sys/amd64/include/clock.h
@@ -27,6 +27,7 @@ void	i8254_init(void);
  * Driver to clock driver interface.
  */
 
+void	startrtclock(void);
 void	init_TSC(void);
 void	init_TSC_tc(void);
 
diff --git a/sys/amd64/isa/clock.c b/sys/amd64/isa/clock.c
index d66505999b34..91598d5306d7 100644
--- a/sys/amd64/isa/clock.c
+++ b/sys/amd64/isa/clock.c
@@ -45,7 +45,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/bus.h>
-#include <sys/clock.h>
 #include <sys/lock.h>
 #include <sys/kdb.h>
 #include <sys/mutex.h>
diff --git a/sys/arm/sa11x0/sa11x0_ost.c b/sys/arm/sa11x0/sa11x0_ost.c
index 6dd4cf34b0a8..1ffb26ca8984 100644
--- a/sys/arm/sa11x0/sa11x0_ost.c
+++ b/sys/arm/sa11x0/sa11x0_ost.c
@@ -45,7 +45,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/kernel.h>
 #include <sys/time.h>
 #include <sys/bus.h>
-#include <sys/clock.h>
 #include <sys/module.h>
 
 #include <machine/bus.h>
diff --git a/sys/i386/bios/apm.c b/sys/i386/bios/apm.c
index a84472834961..61207239d7f9 100644
--- a/sys/i386/bios/apm.c
+++ b/sys/i386/bios/apm.c
@@ -22,7 +22,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/bus.h>
-#include <sys/clock.h>
 #include <sys/conf.h>
 #include <sys/condvar.h>
 #include <sys/eventhandler.h>
diff --git a/sys/i386/i386/machdep.c b/sys/i386/i386/machdep.c
index 54b5e9df5589..b1a0d743b599 100644
--- a/sys/i386/i386/machdep.c
+++ b/sys/i386/i386/machdep.c
@@ -62,7 +62,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/buf.h>
 #include <sys/bus.h>
 #include <sys/callout.h>
-#include <sys/clock.h>
 #include <sys/cons.h>
 #include <sys/cpu.h>
 #include <sys/eventhandler.h>
diff --git a/sys/i386/include/clock.h b/sys/i386/include/clock.h
index 3817e32d3ec0..5a724161bf1c 100644
--- a/sys/i386/include/clock.h
+++ b/sys/i386/include/clock.h
@@ -27,6 +27,7 @@ void	i8254_init(void);
  * Driver to clock driver interface.
  */
 
+void	startrtclock(void);
 void	timer_restore(void);
 void	init_TSC(void);
 void	init_TSC_tc(void);
diff --git a/sys/i386/isa/clock.c b/sys/i386/isa/clock.c
index 3c44baf37c36..93a06a3b9a13 100644
--- a/sys/i386/isa/clock.c
+++ b/sys/i386/isa/clock.c
@@ -48,7 +48,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/bus.h>
-#include <sys/clock.h>
 #include <sys/lock.h>
 #include <sys/kdb.h>
 #include <sys/mutex.h>
diff --git a/sys/i386/isa/pmtimer.c b/sys/i386/isa/pmtimer.c
index 87eda2d4b0a2..1eeac6ddf46b 100644
--- a/sys/i386/isa/pmtimer.c
+++ b/sys/i386/isa/pmtimer.c
@@ -35,7 +35,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/bus.h>
-#include <sys/clock.h>
 #include <sys/kernel.h>
 #include <sys/module.h>
 #include <sys/syslog.h>
diff --git a/sys/ia64/ia64/clock.c b/sys/ia64/ia64/clock.c
index c774dad82635..22fcf9bf452c 100644
--- a/sys/ia64/ia64/clock.c
+++ b/sys/ia64/ia64/clock.c
@@ -29,12 +29,10 @@ __FBSDID("$FreeBSD$");
 
 #include <sys/param.h>
 #include <sys/kernel.h>
-#include <sys/clock.h>
 #include <sys/queue.h>
 #include <sys/sysctl.h>
 #include <sys/systm.h>
 #include <sys/bus.h>
-#include <sys/clock.h>
 #include <sys/timetc.h>
 #include <sys/pcpu.h>
 
diff --git a/sys/ia64/ia64/machdep.c b/sys/ia64/ia64/machdep.c
index 7ce78b8b0c1a..45e57ded9b1e 100644
--- a/sys/ia64/ia64/machdep.c
+++ b/sys/ia64/ia64/machdep.c
@@ -261,7 +261,6 @@ cpu_startup(dummy)
 	 */
 	identifycpu();
 
-	/* startrtclock(); */
 #ifdef PERFMON
 	perfmon_init();
 #endif
diff --git a/sys/kern/subr_clock.c b/sys/kern/subr_clock.c
index e8a847e2236d..ffc70afa353c 100644
--- a/sys/kern/subr_clock.c
+++ b/sys/kern/subr_clock.c
@@ -52,18 +52,14 @@ __FBSDID("$FreeBSD$");
 #define ct_debug bootverbose
 static int adjkerntz;		/* local offset from GMT in seconds */
 static int wall_cmos_clock;	/* wall CMOS clock assumed if != 0 */
-int disable_rtc_set;		/* disable resettodr() if != 0 */
 
 int tz_minuteswest;
 int tz_dsttime;
 
 /*
- * These have traditionally been in machdep, but should probably be moved to
+ * This have traditionally been in machdep, but should probably be moved to
  * kern.
  */
-SYSCTL_INT(_machdep, OID_AUTO, disable_rtc_set,
-	CTLFLAG_RW, &disable_rtc_set, 0, "");
-
 SYSCTL_INT(_machdep, OID_AUTO, wall_cmos_clock,
 	CTLFLAG_RW, &wall_cmos_clock, 0, "");
 
@@ -71,8 +67,7 @@ static int
 sysctl_machdep_adjkerntz(SYSCTL_HANDLER_ARGS)
 {
 	int error;
-	error = sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2,
-		req);
+	error = sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2, req);
 	if (!error && req->newptr)
 		resettodr();
 	return (error);
diff --git a/sys/kern/subr_rtc.c b/sys/kern/subr_rtc.c
index df0df32d6023..1ec10fa7461f 100644
--- a/sys/kern/subr_rtc.c
+++ b/sys/kern/subr_rtc.c
@@ -63,6 +63,11 @@ __FBSDID("$FreeBSD$");
 static device_t clock_dev = NULL;
 static long clock_res;
 
+/* XXX: should be kern. now, it's no longer machdep.  */
+static int disable_rtc_set;
+SYSCTL_INT(_machdep, OID_AUTO, disable_rtc_set,
+	CTLFLAG_RW, &disable_rtc_set, 0, "");
+
 void
 clock_register(device_t dev, long res)	/* res has units of microseconds */
 {
@@ -118,6 +123,7 @@ inittodr(time_t base)
 		    "will not be set accurately\n");
 		return;
 	}
+	/* XXX: We should poll all registered RTCs in case of failure */
 	error = CLOCK_GETTIME(clock_dev, &ts);
 	if (error != 0 && error != EINVAL) {
 		printf("warning: clock_gettime failed (%d), the system time "
@@ -158,6 +164,7 @@ resettodr()
 
 	getnanotime(&ts);
 	ts.tv_sec -= utc_offset();
+	/* XXX: We should really set all registered RTCs */
 	if ((error = CLOCK_SETTIME(clock_dev, &ts)) != 0) {
 		printf("warning: clock_settime failed (%d), time-of-day clock "
 		    "not adjusted to system time\n", error);
diff --git a/sys/kern/vfs_mount.c b/sys/kern/vfs_mount.c
index cfaec358f2d6..34166e739e16 100644
--- a/sys/kern/vfs_mount.c
+++ b/sys/kern/vfs_mount.c
@@ -39,7 +39,6 @@ __FBSDID("$FreeBSD$");
 
 #include <sys/param.h>
 #include <sys/conf.h>
-#include <sys/clock.h>
 #include <sys/fcntl.h>
 #include <sys/jail.h>
 #include <sys/kernel.h>
diff --git a/sys/nfsclient/nfs_vfsops.c b/sys/nfsclient/nfs_vfsops.c
index 7185bb5f4237..aac2e00cee80 100644
--- a/sys/nfsclient/nfs_vfsops.c
+++ b/sys/nfsclient/nfs_vfsops.c
@@ -44,7 +44,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/kernel.h>
 #include <sys/bio.h>
 #include <sys/buf.h>
-#include <sys/clock.h>
 #include <sys/lock.h>
 #include <sys/malloc.h>
 #include <sys/mbuf.h>
diff --git a/sys/pc98/cbus/clock.c b/sys/pc98/cbus/clock.c
index ff4bd8f3931f..86dc687a8647 100644
--- a/sys/pc98/cbus/clock.c
+++ b/sys/pc98/cbus/clock.c
@@ -51,7 +51,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/bus.h>
-#include <sys/clock.h>
 #include <sys/lock.h>
 #include <sys/kdb.h>
 #include <sys/mutex.h>
diff --git a/sys/pc98/pc98/machdep.c b/sys/pc98/pc98/machdep.c
index dd524c99b247..942b80478c53 100644
--- a/sys/pc98/pc98/machdep.c
+++ b/sys/pc98/pc98/machdep.c
@@ -60,7 +60,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/buf.h>
 #include <sys/bus.h>
 #include <sys/callout.h>
-#include <sys/clock.h>
 #include <sys/cons.h>
 #include <sys/cpu.h>
 #include <sys/eventhandler.h>
diff --git a/sys/powerpc/aim/clock.c b/sys/powerpc/aim/clock.c
index 01164751faac..1911220dfbad 100644
--- a/sys/powerpc/aim/clock.c
+++ b/sys/powerpc/aim/clock.c
@@ -63,7 +63,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/kernel.h>
 #include <sys/sysctl.h>
 #include <sys/bus.h>
-#include <sys/clock.h>
 #include <sys/timetc.h>
 #include <sys/interrupt.h>
 
diff --git a/sys/powerpc/aim/machdep.c b/sys/powerpc/aim/machdep.c
index f28d5c20de9a..d40731443f2c 100644
--- a/sys/powerpc/aim/machdep.c
+++ b/sys/powerpc/aim/machdep.c
@@ -196,7 +196,6 @@ cpu_startup(void *dummy)
 	 */
 	cpu_setup(PCPU_GET(cpuid));
 
-	/* startrtclock(); */
 #ifdef PERFMON
 	perfmon_init();
 #endif
diff --git a/sys/powerpc/booke/clock.c b/sys/powerpc/booke/clock.c
index 3ba58c0fc72e..707016121e54 100644
--- a/sys/powerpc/booke/clock.c
+++ b/sys/powerpc/booke/clock.c
@@ -63,7 +63,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/kernel.h>
 #include <sys/sysctl.h>
 #include <sys/bus.h>
-#include <sys/clock.h>
 #include <sys/timetc.h>
 #include <sys/interrupt.h>
 
diff --git a/sys/sys/clock.h b/sys/sys/clock.h
index 00f682148238..c08683eb1b4c 100644
--- a/sys/sys/clock.h
+++ b/sys/sys/clock.h
@@ -35,6 +35,19 @@
  *
  *	$NetBSD: clock_subr.h,v 1.7 2000/10/03 13:41:07 tsutsui Exp $
  *
+ *
+ * This file is the central clearing-house for calendrical issues.
+ *
+ * In general the kernel does not know about minutes, hours, days, timezones,
+ * daylight savings time, leap-years and such.  All that is theoretically a
+ * matter for userland only.
+ *
+ * Parts of kernel code does however care: badly designed filesystems store
+ * timestamps in local time and RTC chips sometimes track time in a local
+ * timezone instead of UTC and so on.
+ *
+ * All that code should go here for service.
+ *
  * $FreeBSD$
  */
 
@@ -43,15 +56,6 @@
 
 #ifdef _KERNEL		/* No user serviceable parts */
 
-/*
- * Kernel to clock driver interface.
- */
-void	inittodr(time_t base);
-void	resettodr(void);
-void	startrtclock(void);
-
-extern int	disable_rtc_set;
-
 /*
  * Timezone info from settimeofday(2), usually not used
  */
diff --git a/sys/sys/time.h b/sys/sys/time.h
index b12b6d89ad54..320a12124a6c 100644
--- a/sys/sys/time.h
+++ b/sys/sys/time.h
@@ -255,6 +255,13 @@ struct clockinfo {
 #endif
 
 #ifdef _KERNEL
+
+/*
+ * Kernel to clock driver interface.
+ */
+void	inittodr(time_t base);
+void	resettodr(void);
+
 extern time_t	time_second;
 extern time_t	time_uptime;
 extern struct timeval boottime;