Merge branch 'timers-for-linus-cleanups' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'timers-for-linus-cleanups' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  avr32: Fix typo in read_persistent_clock()
  sparc: Convert sparc to use read/update_persistent_clock
  cris: Convert cris to use read/update_persistent_clock
  m68k: Convert m68k to use read/update_persistent_clock
  m32r: Convert m32r to use read/update_peristent_clock
  blackfin: Convert blackfin to use read/update_persistent_clock
  ia64: Convert ia64 to use read/update_persistent_clock
  avr32: Convert avr32 to use read/update_persistent_clock
  h8300: Convert h8300 to use read/update_persistent_clock
  frv: Convert frv to use read/update_persistent_clock
  mn10300: Convert mn10300 to use read/update_persistent_clock
  alpha: Convert alpha to use read/update_persistent_clock
  xtensa: Fix unnecessary setting of xtime
  time: Clean up direct xtime usage in xen

21 files changed, 137 insertions, 310 deletions

diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig
index 75291fdd379..b7193986cbf 100644
--- a/arch/alpha/Kconfig
+++ b/arch/alpha/Kconfig
@@ -55,6 +55,9 @@ config ARCH_USES_GETTIMEOFFSET
         bool
         default y
 
+config GENERIC_CMOS_UPDATE
+        def_bool y
+
 config ZONE_DMA
         bool
         default y
diff --git a/arch/alpha/kernel/time.c b/arch/alpha/kernel/time.c
index 5d0826654c6..5465e932e56 100644
--- a/arch/alpha/kernel/time.c
+++ b/arch/alpha/kernel/time.c
@@ -75,8 +75,6 @@ static struct {
         __u32 last_time;
         /* ticks/cycle * 2^48 */
         unsigned long scaled_ticks_per_cycle;
-        /* last time the CMOS clock got updated */
-        time_t last_rtc_update;
         /* partial unused tick */
         unsigned long partial_tick;
 } state;
@@ -91,6 +89,52 @@ static inline __u32 rpcc(void)
     return result;
 }
 
+int update_persistent_clock(struct timespec now)
+{
+        return set_rtc_mmss(now.tv_sec);
+}
+
+void read_persistent_clock(struct timespec *ts)
+{
+        unsigned int year, mon, day, hour, min, sec, epoch;
+
+        sec = CMOS_READ(RTC_SECONDS);
+        min = CMOS_READ(RTC_MINUTES);
+        hour = CMOS_READ(RTC_HOURS);
+        day = CMOS_READ(RTC_DAY_OF_MONTH);
+        mon = CMOS_READ(RTC_MONTH);
+        year = CMOS_READ(RTC_YEAR);
+
+        if (!(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
+                sec = bcd2bin(sec);
+                min = bcd2bin(min);
+                hour = bcd2bin(hour);
+                day = bcd2bin(day);
+                mon = bcd2bin(mon);
+                year = bcd2bin(year);
+        }
+
+        /* PC-like is standard; used for year >= 70 */
+        epoch = 1900;
+        if (year < 20)
+                epoch = 2000;
+        else if (year >= 20 && year < 48)
+                /* NT epoch */
+                epoch = 1980;
+        else if (year >= 48 && year < 70)
+                /* Digital UNIX epoch */
+                epoch = 1952;
+
+        printk(KERN_INFO "Using epoch = %d\n", epoch);
+
+        if ((year += epoch) < 1970)
+                year += 100;
+
+        ts->tv_sec = mktime(year, mon, day, hour, min, sec);
+}
+
+
+
 /*
  * timer_interrupt() needs to keep up the real-time clock,
  * as well as call the "do_timer()" routine every clocktick
@@ -123,19 +167,6 @@ irqreturn_t timer_interrupt(int irq, void *dev)
         if (nticks)
                 do_timer(nticks);
 
-        /*
-         * If we have an externally synchronized Linux clock, then update
-         * 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 (ntp_synced()
-            && xtime.tv_sec > state.last_rtc_update + 660
-            && xtime.tv_nsec >= 500000 - ((unsigned) TICK_SIZE) / 2
-            && xtime.tv_nsec <= 500000 + ((unsigned) TICK_SIZE) / 2) {
-                int tmp = set_rtc_mmss(xtime.tv_sec);
-                state.last_rtc_update = xtime.tv_sec - (tmp ? 600 : 0);
-        }
-
         write_sequnlock(&xtime_lock);
 
 #ifndef CONFIG_SMP
@@ -304,7 +335,7 @@ rpcc_after_update_in_progress(void)
 void __init
 time_init(void)
 {
-        unsigned int year, mon, day, hour, min, sec, cc1, cc2, epoch;
+        unsigned int cc1, cc2;
         unsigned long cycle_freq, tolerance;
         long diff;
 
@@ -348,43 +379,6 @@ time_init(void)
            bogomips yet, but this is close on a 500Mhz box.  */
         __delay(1000000);
 
-        sec = CMOS_READ(RTC_SECONDS);
-        min = CMOS_READ(RTC_MINUTES);
-        hour = CMOS_READ(RTC_HOURS);
-        day = CMOS_READ(RTC_DAY_OF_MONTH);
-        mon = CMOS_READ(RTC_MONTH);
-        year = CMOS_READ(RTC_YEAR);
-
-        if (!(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
-                sec = bcd2bin(sec);
-                min = bcd2bin(min);
-                hour = bcd2bin(hour);
-                day = bcd2bin(day);
-                mon = bcd2bin(mon);
-                year = bcd2bin(year);
-        }
-
-        /* PC-like is standard; used for year >= 70 */
-        epoch = 1900;
-        if (year < 20)
-                epoch = 2000;
-        else if (year >= 20 && year < 48)
-                /* NT epoch */
-                epoch = 1980;
-        else if (year >= 48 && year < 70)
-                /* Digital UNIX epoch */
-                epoch = 1952;
-
-        printk(KERN_INFO "Using epoch = %d\n", epoch);
-
-        if ((year += epoch) < 1970)
-                year += 100;
-
-        xtime.tv_sec = mktime(year, mon, day, hour, min, sec);
-        xtime.tv_nsec = 0;
-
-        wall_to_monotonic.tv_sec -= xtime.tv_sec;
-        wall_to_monotonic.tv_nsec = 0;
 
         if (HZ > (1<<16)) {
                 extern void __you_loose (void);
@@ -394,7 +388,6 @@ time_init(void)
         state.last_time = cc1;
         state.scaled_ticks_per_cycle
                 = ((unsigned long) HZ << FIX_SHIFT) / cycle_freq;
-        state.last_rtc_update = 0;
         state.partial_tick = 0L;
 
         /* Startup the timer source. */
diff --git a/arch/avr32/kernel/time.c b/arch/avr32/kernel/time.c
index f27aa3b259f..668ed2817e5 100644
--- a/arch/avr32/kernel/time.c
+++ b/arch/avr32/kernel/time.c
@@ -110,17 +110,17 @@ static struct clock_event_device comparator = {
         .set_mode       = comparator_mode,
 };
 
+void read_persistent_clock(struct timespec *ts)
+{
+        ts->tv_sec = mktime(2007, 1, 1, 0, 0, 0);
+        ts->tv_nsec = 0;
+}
+
 void __init time_init(void)
 {
         unsigned long counter_hz;
         int ret;
 
-        xtime.tv_sec = mktime(2007, 1, 1, 0, 0, 0);
-        xtime.tv_nsec = 0;
-
-        set_normalized_timespec(&wall_to_monotonic,
-                                -xtime.tv_sec, -xtime.tv_nsec);
-
         /* figure rate for counter */
         counter_hz = clk_get_rate(boot_cpu_data.clk);
         counter.mult = clocksource_hz2mult(counter_hz, counter.shift);
diff --git a/arch/blackfin/kernel/time-ts.c b/arch/blackfin/kernel/time-ts.c
index cb7a01d4f00..8c9a43daf80 100644
--- a/arch/blackfin/kernel/time-ts.c
+++ b/arch/blackfin/kernel/time-ts.c
@@ -353,9 +353,15 @@ void bfin_coretmr_clockevent_init(void)
 #endif /* CONFIG_TICKSOURCE_CORETMR */
 
 
-void __init time_init(void)
+void read_persistent_clock(struct timespec *ts)
 {
         time_t secs_since_1970 = (365 * 37 + 9) * 24 * 60 * 60; /* 1 Jan 2007 */
+        ts->tv_sec = secs_since_1970;
+        ts->tv_nsec = 0;
+}
+
+void __init time_init(void)
+{
 
 #ifdef CONFIG_RTC_DRV_BFIN
         /* [#2663] hack to filter junk RTC values that would cause
@@ -368,11 +374,6 @@ void __init time_init(void)
         }
 #endif
 
-        /* Initialize xtime. From now on, xtime is updated with timer interrupts */
-        xtime.tv_sec = secs_since_1970;
-        xtime.tv_nsec = 0;
-        set_normalized_timespec(&wall_to_monotonic, -xtime.tv_sec, -xtime.tv_nsec);
-
         bfin_cs_cycles_init();
         bfin_cs_gptimer0_init();
 
diff --git a/arch/blackfin/kernel/time.c b/arch/blackfin/kernel/time.c
index 13c1ee3e640..c9113619029 100644
--- a/arch/blackfin/kernel/time.c
+++ b/arch/blackfin/kernel/time.c
@@ -112,11 +112,6 @@ u32 arch_gettimeoffset(void)
 }
 #endif
 
-static inline int set_rtc_mmss(unsigned long nowtime)
-{
-        return 0;
-}
-
 /*
  * timer_interrupt() needs to keep up the real-time clock,
  * as well as call the "do_timer()" routine every clocktick
@@ -126,29 +121,8 @@ __attribute__((l1_text))
 #endif
 irqreturn_t timer_interrupt(int irq, void *dummy)
 {
-        /* last time the cmos clock got updated */
-        static long last_rtc_update;
-
         write_seqlock(&xtime_lock);
         do_timer(1);
-
-        /*
-         * If we have an externally synchronized Linux clock, then update
-         * 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 (ntp_synced() &&
-            xtime.tv_sec > last_rtc_update + 660 &&
-            (xtime.tv_nsec / NSEC_PER_USEC) >=
-            500000 - ((unsigned)TICK_SIZE) / 2
-            && (xtime.tv_nsec / NSEC_PER_USEC) <=
-            500000 + ((unsigned)TICK_SIZE) / 2) {
-                if (set_rtc_mmss(xtime.tv_sec) == 0)
-                        last_rtc_update = xtime.tv_sec;
-                else
-                        /* Do it again in 60s. */
-                        last_rtc_update = xtime.tv_sec - 600;
-        }
         write_sequnlock(&xtime_lock);
 
 #ifdef CONFIG_IPIPE
@@ -161,10 +135,15 @@ irqreturn_t timer_interrupt(int irq, void *dummy)
         return IRQ_HANDLED;
 }
 
-void __init time_init(void)
+void read_persistent_clock(struct timespec *ts)
 {
         time_t secs_since_1970 = (365 * 37 + 9) * 24 * 60 * 60; /* 1 Jan 2007 */
+        ts->tv_sec = secs_since_1970;
+        ts->tv_nsec = 0;
+}
 
+void __init time_init(void)
+{
 #ifdef CONFIG_RTC_DRV_BFIN
         /* [#2663] hack to filter junk RTC values that would cause
          * userspace to have to deal with time values greater than
@@ -176,11 +155,5 @@ void __init time_init(void)
         }
 #endif
 
-        /* Initialize xtime. From now on, xtime is updated with timer interrupts */
-        xtime.tv_sec = secs_since_1970;
-        xtime.tv_nsec = 0;
-
-        wall_to_monotonic.tv_sec = -xtime.tv_sec;
-
         time_sched_init(timer_interrupt);
 }
diff --git a/arch/cris/Kconfig b/arch/cris/Kconfig
index 059eac6abda..e25bf4440b5 100644
--- a/arch/cris/Kconfig
+++ b/arch/cris/Kconfig
@@ -23,6 +23,9 @@ config RWSEM_XCHGADD_ALGORITHM
 config GENERIC_TIME
         def_bool y
 
+config GENERIC_CMOS_UPDATE
+        def_bool y
+
 config ARCH_USES_GETTIMEOFFSET
         def_bool y
 
diff --git a/arch/cris/arch-v10/kernel/time.c b/arch/cris/arch-v10/kernel/time.c
index 31ca1418d5a..30adae594ae 100644
--- a/arch/cris/arch-v10/kernel/time.c
+++ b/arch/cris/arch-v10/kernel/time.c
@@ -26,7 +26,6 @@
 /* it will make jiffies at 96 hz instead of 100 hz though */
 #undef USE_CASCADE_TIMERS
 
-extern void update_xtime_from_cmos(void);
 extern int set_rtc_mmss(unsigned long nowtime);
 extern int have_rtc;
 
@@ -188,8 +187,6 @@ stop_watchdog(void)
 #endif  
 }
 
-/* last time the cmos clock got updated */
-static long last_rtc_update = 0;
 
 /*
  * timer_interrupt() needs to keep up the real-time clock,
@@ -232,24 +229,6 @@ timer_interrupt(int irq, void *dev_id)
         do_timer(1);
         
         cris_do_profile(regs); /* Save profiling information */
-
-        /*
-         * If we have an externally synchronized Linux clock, then update
-         * 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.
-         *
-         * The division here is not time critical since it will run once in 
-         * 11 minutes
-         */
-        if (ntp_synced() &&
-            xtime.tv_sec > last_rtc_update + 660 &&
-            (xtime.tv_nsec / 1000) >= 500000 - (tick_nsec / 1000) / 2 &&
-            (xtime.tv_nsec / 1000) <= 500000 + (tick_nsec / 1000) / 2) {
-                if (set_rtc_mmss(xtime.tv_sec) == 0)
-                        last_rtc_update = xtime.tv_sec;
-                else
-                        last_rtc_update = xtime.tv_sec - 600; /* do it again in 60 s */
-        }
         return IRQ_HANDLED;
 }
 
@@ -274,22 +253,10 @@ time_init(void)
          */
         loops_per_usec = 50;
 
-        if(RTC_INIT() < 0) {
-                /* no RTC, start at 1980 */
-                xtime.tv_sec = 0;
-                xtime.tv_nsec = 0;
+        if(RTC_INIT() < 0)
                 have_rtc = 0;
-        } else {                
-                /* get the current time */
+        else
                 have_rtc = 1;
-                update_xtime_from_cmos();
-        }
-
-        /*
-         * Initialize wall_to_monotonic such that adding it to xtime will yield zero, the
-         * tv_nsec field must be normalized (i.e., 0 <= nsec < NSEC_PER_SEC).
-         */
-        set_normalized_timespec(&wall_to_monotonic, -xtime.tv_sec, -xtime.tv_nsec);
 
         /* Setup the etrax timers
          * Base frequency is 25000 hz, divider 250 -> 100 HZ
diff --git a/arch/cris/arch-v32/kernel/time.c b/arch/cris/arch-v32/kernel/time.c
index b1920d8de40..1ee0e101022 100644
--- a/arch/cris/arch-v32/kernel/time.c
+++ b/arch/cris/arch-v32/kernel/time.c
@@ -44,7 +44,6 @@ unsigned long timer_regs[NR_CPUS] =
 #endif
 };
 
-extern void update_xtime_from_cmos(void);
 extern int set_rtc_mmss(unsigned long nowtime);
 extern int have_rtc;
 
@@ -198,9 +197,6 @@ handle_watchdog_bite(struct pt_regs* regs)
 #endif
 }
 
-/* Last time the cmos clock got updated. */
-static long last_rtc_update = 0;
-
 /*
  * timer_interrupt() needs to keep up the real-time clock,
  * as well as call the "do_timer()" routine every clocktick.
@@ -238,25 +234,6 @@ timer_interrupt(int irq, void *dev_id)
 
         /* Call the real timer interrupt handler */
         do_timer(1);
-
-        /*
-         * If we have an externally synchronized Linux clock, then update
-         * 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.
-         *
-         * The division here is not time critical since it will run once in
-         * 11 minutes
-         */
-        if ((time_status & STA_UNSYNC) == 0 &&
-            xtime.tv_sec > last_rtc_update + 660 &&
-            (xtime.tv_nsec / 1000) >= 500000 - (tick_nsec / 1000) / 2 &&
-            (xtime.tv_nsec / 1000) <= 500000 + (tick_nsec / 1000) / 2) {
-                if (set_rtc_mmss(xtime.tv_sec) == 0)
-                        last_rtc_update = xtime.tv_sec;
-                else
-                        /* Do it again in 60 s */
-                        last_rtc_update = xtime.tv_sec - 600;
-        }
         return IRQ_HANDLED;
 }
 
@@ -309,23 +286,10 @@ time_init(void)
          */
         loops_per_usec = 50;
 
-        if(RTC_INIT() < 0) {
-                /* No RTC, start at 1980 */
-                xtime.tv_sec = 0;
-                xtime.tv_nsec = 0;
+        if(RTC_INIT() < 0)
                 have_rtc = 0;
-        } else {
-                /* Get the current time */
+        else
                 have_rtc = 1;
-                update_xtime_from_cmos();
-        }
-
-        /*
-         * Initialize wall_to_monotonic such that adding it to
-         * xtime will yield zero, the tv_nsec field must be normalized
-         * (i.e., 0 <= nsec < NSEC_PER_SEC).
-         */
-        set_normalized_timespec(&wall_to_monotonic, -xtime.tv_sec, -xtime.tv_nsec);
 
         /* Start CPU local timer. */
         cris_timer_init();
diff --git a/arch/cris/kernel/time.c b/arch/cris/kernel/time.c
index a05dd31f3ef..c72730d20ef 100644
--- a/arch/cris/kernel/time.c
+++ b/arch/cris/kernel/time.c
@@ -98,6 +98,8 @@ unsigned long
 get_cmos_time(void)
 {
         unsigned int year, mon, day, hour, min, sec;
+        if(!have_rtc)
+                return 0;
 
         sec = CMOS_READ(RTC_SECONDS);
         min = CMOS_READ(RTC_MINUTES);
@@ -119,19 +121,19 @@ get_cmos_time(void)
         return mktime(year, mon, day, hour, min, sec);
 }
 
-/* update xtime from the CMOS settings. used when /dev/rtc gets a SET_TIME.
- * TODO: this doesn't reset the fancy NTP phase stuff as do_settimeofday does.
- */
 
-void
-update_xtime_from_cmos(void)
+int update_persistent_clock(struct timespec now)
 {
-        if(have_rtc) {
-                xtime.tv_sec = get_cmos_time();
-                xtime.tv_nsec = 0;
-        }
+        return set_rtc_mmss(now.tv_sec);
 }
 
+void read_persistent_clock(struct timespec *ts)
+{
+        ts->tv_sec = get_cmos_time();
+        ts->tv_nsec = 0;
+}
+
+
 extern void cris_profile_sample(struct pt_regs* regs);
 
 void
diff --git a/arch/frv/kernel/time.c b/arch/frv/kernel/time.c
index fb0ce757722..0ddbbae83cb 100644
--- a/arch/frv/kernel/time.c
+++ b/arch/frv/kernel/time.c
@@ -48,20 +48,12 @@ static struct irqaction timer_irq  = {
         .name = "timer",
 };
 
-static inline int set_rtc_mmss(unsigned long nowtime)
-{
-        return -1;
-}
-
 /*
  * timer_interrupt() needs to keep up the real-time clock,
  * as well as call the "do_timer()" routine every clocktick
  */
 static irqreturn_t timer_interrupt(int irq, void *dummy)
 {
-        /* last time the cmos clock got updated */
-        static long last_rtc_update = 0;
-
         profile_tick(CPU_PROFILING);
         /*
          * Here we are in the timer irq handler. We just have irqs locally
@@ -74,22 +66,6 @@ static irqreturn_t timer_interrupt(int irq, void *dummy)
 
         do_timer(1);
 
-        /*
-         * If we have an externally synchronized Linux clock, then update
-         * 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 (ntp_synced() &&
-            xtime.tv_sec > last_rtc_update + 660 &&
-            (xtime.tv_nsec / 1000) >= 500000 - ((unsigned) TICK_SIZE) / 2 &&
-            (xtime.tv_nsec / 1000) <= 500000 + ((unsigned) TICK_SIZE) / 2
-            ) {
-                if (set_rtc_mmss(xtime.tv_sec) == 0)
-                        last_rtc_update = xtime.tv_sec;
-                else
-                        last_rtc_update = xtime.tv_sec - 600; /* do it again in 60 s */
-        }
-
 #ifdef CONFIG_HEARTBEAT
         static unsigned short n;
         n++;
@@ -119,7 +95,8 @@ void time_divisor_init(void)
         __set_TCSR_DATA(0, base >> 8);
 }
 
-void time_init(void)
+
+void read_persistent_clock(struct timespec *ts)
 {
         unsigned int year, mon, day, hour, min, sec;
 
@@ -135,9 +112,12 @@ void time_init(void)
 
         if ((year += 1900) < 1970)
                 year += 100;
-        xtime.tv_sec = mktime(year, mon, day, hour, min, sec);
-        xtime.tv_nsec = 0;
+        ts->tv_sec = mktime(year, mon, day, hour, min, sec);
+        ts->tv_nsec = 0;
+}
 
+void time_init(void)
+{
         /* install scheduling interrupt handler */
         setup_irq(IRQ_CPU_TIMER0, &timer_irq);
 
diff --git a/arch/h8300/kernel/time.c b/arch/h8300/kernel/time.c
index 7f2d6cfbb4b..165005aff9d 100644
--- a/arch/h8300/kernel/time.c
+++ b/arch/h8300/kernel/time.c
@@ -41,7 +41,7 @@ void h8300_timer_tick(void)
         update_process_times(user_mode(get_irq_regs()));
 }
 
-void __init time_init(void)
+void read_persistent_clock(struct timespec *ts)
 {
         unsigned int year, mon, day, hour, min, sec;
 
@@ -56,8 +56,12 @@ void __init time_init(void)
 #endif
         if ((year += 1900) < 1970)
                 year += 100;
-        xtime.tv_sec = mktime(year, mon, day, hour, min, sec);
-        xtime.tv_nsec = 0;
+        ts->tv_sec = mktime(year, mon, day, hour, min, sec);
+        ts->tv_nsec = 0;
+}
+
+void __init time_init(void)
+{
 
         h8300_timer_setup();
 }
diff --git a/arch/ia64/kernel/time.c b/arch/ia64/kernel/time.c
index 47a192781b0..653b3c46ea8 100644
--- a/arch/ia64/kernel/time.c
+++ b/arch/ia64/kernel/time.c
@@ -430,18 +430,16 @@ static int __init rtc_init(void)
 }
 module_init(rtc_init);
 
+void read_persistent_clock(struct timespec *ts)
+{
+        efi_gettimeofday(ts);
+}
+
 void __init
 time_init (void)
 {
         register_percpu_irq(IA64_TIMER_VECTOR, &timer_irqaction);
-        efi_gettimeofday(&xtime);
         ia64_init_itm();
-
-        /*
-         * Initialize wall_to_monotonic such that adding it to xtime will yield zero, the
-         * tv_nsec field must be normalized (i.e., 0 <= nsec < NSEC_PER_SEC).
-         */
-        set_normalized_timespec(&wall_to_monotonic, -xtime.tv_sec, -xtime.tv_nsec);
 }
 
 /*
diff --git a/arch/m32r/kernel/time.c b/arch/m32r/kernel/time.c
index 9cedcef1157..bda86820bff 100644
--- a/arch/m32r/kernel/time.c
+++ b/arch/m32r/kernel/time.c
@@ -106,24 +106,6 @@ u32 arch_gettimeoffset(void)
 }
 
 /*
- * In order to set the CMOS clock precisely, set_rtc_mmss has to be
- * called 500 ms after the second nowtime has started, because when
- * 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 won't notice until after reboot!
- */
-static inline int set_rtc_mmss(unsigned long nowtime)
-{
-        return 0;
-}
-
-/* last time the cmos clock got updated */
-static long last_rtc_update = 0;
-
-/*
  * timer_interrupt() needs to keep up the real-time clock,
  * as well as call the "do_timer()" routine every clocktick
  */
@@ -138,23 +120,6 @@ static irqreturn_t timer_interrupt(int irq, void *dev_id)
 #ifndef CONFIG_SMP
         update_process_times(user_mode(get_irq_regs()));
 #endif
-        /*
-         * If we have an externally synchronized Linux clock, then update
-         * 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.
-         */
-        write_seqlock(&xtime_lock);
-        if (ntp_synced()
-                && xtime.tv_sec > last_rtc_update + 660
-                && (xtime.tv_nsec / 1000) >= 500000 - ((unsigned)TICK_SIZE) / 2
-                && (xtime.tv_nsec / 1000) <= 500000 + ((unsigned)TICK_SIZE) / 2)
-        {
-                if (set_rtc_mmss(xtime.tv_sec) == 0)
-                        last_rtc_update = xtime.tv_sec;
-                else    /* do it again in 60 s */
-                        last_rtc_update = xtime.tv_sec - 600;
-        }
-        write_sequnlock(&xtime_lock);
         /* As we return to user mode fire off the other CPU schedulers..
            this is basically because we don't yet share IRQ's around.
            This message is rigged to be safe on the 386 - basically it's
@@ -174,7 +139,7 @@ static struct irqaction irq0 = {
         .name = "MFT2",
 };
 
-void __init time_init(void)
+void read_persistent_clock(struct timespec *ts)
 {
         unsigned int epoch, year, mon, day, hour, min, sec;
 
@@ -194,11 +159,13 @@ void __init time_init(void)
                 epoch = 1952;
         year += epoch;
 
-        xtime.tv_sec = mktime(year, mon, day, hour, min, sec);
-        xtime.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);
-        set_normalized_timespec(&wall_to_monotonic,
-                -xtime.tv_sec, -xtime.tv_nsec);
+        ts->tv_sec = mktime(year, mon, day, hour, min, sec);
+        ts->tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);
+}
 
+
+void __init time_init(void)
+{
 #if defined(CONFIG_CHIP_M32102) || defined(CONFIG_CHIP_XNUX2) \
         || defined(CONFIG_CHIP_VDEC2) || defined(CONFIG_CHIP_M32700) \
         || defined(CONFIG_CHIP_OPSP) || defined(CONFIG_CHIP_M32104)
diff --git a/arch/m68k/kernel/time.c b/arch/m68k/kernel/time.c
index 17dc2a31a7c..4926b3856c1 100644
--- a/arch/m68k/kernel/time.c
+++ b/arch/m68k/kernel/time.c
@@ -73,21 +73,24 @@ static irqreturn_t timer_interrupt(int irq, void *dummy)
         return IRQ_HANDLED;
 }
 
-void __init time_init(void)
+void read_persistent_clock(struct timespec *ts)
 {
         struct rtc_time time;
+        ts->tv_sec = 0;
+        ts->tv_nsec = 0;
 
         if (mach_hwclk) {
                 mach_hwclk(0, &time);
 
                 if ((time.tm_year += 1900) < 1970)
                         time.tm_year += 100;
-                xtime.tv_sec = mktime(time.tm_year, time.tm_mon, time.tm_mday,
+                ts->tv_sec = mktime(time.tm_year, time.tm_mon, time.tm_mday,
                                       time.tm_hour, time.tm_min, time.tm_sec);
-                xtime.tv_nsec = 0;
         }
-        wall_to_monotonic.tv_sec = -xtime.tv_sec;
+}
 
+void __init time_init(void)
+{
         mach_sched_init(timer_interrupt);
 }
 
diff --git a/arch/mn10300/Kconfig b/arch/mn10300/Kconfig
index 89faacad5d1..1c4565a9102 100644
--- a/arch/mn10300/Kconfig
+++ b/arch/mn10300/Kconfig
@@ -37,6 +37,9 @@ config GENERIC_HARDIRQS_NO__DO_IRQ
 config GENERIC_CALIBRATE_DELAY
         def_bool y
 
+config GENERIC_CMOS_UPDATE
+        def_bool y
+
 config GENERIC_FIND_NEXT_BIT
         def_bool y
 
diff --git a/arch/mn10300/kernel/rtc.c b/arch/mn10300/kernel/rtc.c
index 7978470b574..815a933aafa 100644
--- a/arch/mn10300/kernel/rtc.c
+++ b/arch/mn10300/kernel/rtc.c
@@ -26,17 +26,15 @@ static long last_rtc_update;
 /* time for RTC to update itself in ioclks */
 static unsigned long mn10300_rtc_update_period;
 
-/*
- * read the current RTC time
- */
-unsigned long __init get_initial_rtc_time(void)
+void read_persistent_clock(struct timespec *ts)
 {
         struct rtc_time tm;
 
         get_rtc_time(&tm);
 
-        return mktime(tm.tm_year, tm.tm_mon, tm.tm_mday,
+        ts->tv_sec = mktime(tm.tm_year, tm.tm_mon, tm.tm_mday,
                       tm.tm_hour, tm.tm_min, tm.tm_sec);
+        ts->tv_nsec = 0;
 }
 
 /*
@@ -110,24 +108,9 @@ static int set_rtc_mmss(unsigned long nowtime)
         return retval;
 }
 
-void check_rtc_time(void)
+int update_persistent_clock(struct timespec now)
 {
-        /* the RTC clock just finished ticking over again this second
-         * - if we have an externally synchronized Linux clock, then update
-         *   RTC 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_status & STA_UNSYNC) == 0 &&
-            xtime.tv_sec > last_rtc_update + 660 &&
-            xtime.tv_nsec / 1000 >= 500000 - ((unsigned) TICK_SIZE) / 2 &&
-            xtime.tv_nsec / 1000 <= 500000 + ((unsigned) TICK_SIZE) / 2
-            ) {
-                if (set_rtc_mmss(xtime.tv_sec) == 0)
-                        last_rtc_update = xtime.tv_sec;
-                else
-                        /* do it again in 60s */
-                        last_rtc_update = xtime.tv_sec - 600;
-        }
+        return set_rtc_mms(now.tv_sec);
 }
 
 /*
diff --git a/arch/mn10300/kernel/time.c b/arch/mn10300/kernel/time.c
index 395caf01b90..8f7f6d22783 100644
--- a/arch/mn10300/kernel/time.c
+++ b/arch/mn10300/kernel/time.c
@@ -111,7 +111,6 @@ static irqreturn_t timer_interrupt(int irq, void *dev_id)
                 /* advance the kernel's time tracking system */
                 profile_tick(CPU_PROFILING);
                 do_timer(1);
-                check_rtc_time();
         }
 
         write_sequnlock(&xtime_lock);
@@ -139,9 +138,6 @@ void __init time_init(void)
                " (calibrated against RTC)\n",
                MN10300_TSCCLK / 1000000, (MN10300_TSCCLK / 10000) % 100);
 
-        xtime.tv_sec = get_initial_rtc_time();
-        xtime.tv_nsec = 0;
-
         mn10300_last_tsc = TMTSCBC;
 
         /* use timer 0 & 1 cascaded to tick at as close to HZ as possible */
diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index 9908d477ccd..d6781ce687e 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -75,7 +75,7 @@ config ARCH_USES_GETTIMEOFFSET
 
 config GENERIC_CMOS_UPDATE
         bool
-        default y if SPARC64
+        default y
 
 config GENERIC_CLOCKEVENTS
         bool
diff --git a/arch/sparc/kernel/time_32.c b/arch/sparc/kernel/time_32.c
index 0d4c09b15ef..4453003032b 100644
--- a/arch/sparc/kernel/time_32.c
+++ b/arch/sparc/kernel/time_32.c
@@ -78,6 +78,11 @@ __volatile__ unsigned int *master_l10_counter;
 
 u32 (*do_arch_gettimeoffset)(void);
 
+int update_persistent_clock(struct timespec now)
+{
+        return set_rtc_mmss(now.tv_sec);
+}
+
 /*
  * timer_interrupt() needs to keep up the real-time clock,
  * as well as call the "do_timer()" routine every clocktick
@@ -87,9 +92,6 @@ u32 (*do_arch_gettimeoffset)(void);
 
 static irqreturn_t timer_interrupt(int dummy, void *dev_id)
 {
-        /* last time the cmos clock got updated */
-        static long last_rtc_update;
-
 #ifndef CONFIG_SMP
         profile_tick(CPU_PROFILING);
 #endif
@@ -101,16 +103,6 @@ static irqreturn_t timer_interrupt(int dummy, void *dev_id)
 
         do_timer(1);
 
-        /* Determine when to update the Mostek clock. */
-        if (ntp_synced() &&
-            xtime.tv_sec > last_rtc_update + 660 &&
-            (xtime.tv_nsec / 1000) >= 500000 - ((unsigned) TICK_SIZE) / 2 &&
-            (xtime.tv_nsec / 1000) <= 500000 + ((unsigned) TICK_SIZE) / 2) {
-          if (set_rtc_mmss(xtime.tv_sec) == 0)
-            last_rtc_update = xtime.tv_sec;
-          else
-            last_rtc_update = xtime.tv_sec - 600; /* do it again in 60 s */
-        }
         write_sequnlock(&xtime_lock);
 
 #ifndef CONFIG_SMP
diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c
index 32764b8880b..b3c6c59ed30 100644
--- a/arch/x86/xen/time.c
+++ b/arch/x86/xen/time.c
@@ -476,6 +476,7 @@ void xen_timer_resume(void)
 __init void xen_time_init(void)
 {
         int cpu = smp_processor_id();
+        struct timespec tp;
 
         clocksource_register(&xen_clocksource);
 
@@ -487,9 +488,8 @@ __init void xen_time_init(void)
         }
 
         /* Set initial system time with full resolution */
-        xen_read_wallclock(&xtime);
-        set_normalized_timespec(&wall_to_monotonic,
-                                -xtime.tv_sec, -xtime.tv_nsec);
+        xen_read_wallclock(&tp);
+        do_settimeofday(&tp);
 
         setup_force_cpu_cap(X86_FEATURE_TSC);
 
diff --git a/arch/xtensa/kernel/time.c b/arch/xtensa/kernel/time.c
index 19f7df30937..19df764f639 100644
--- a/arch/xtensa/kernel/time.c
+++ b/arch/xtensa/kernel/time.c
@@ -60,11 +60,6 @@ static struct irqaction timer_irqaction = {
 
 void __init time_init(void)
 {
-        /* FIXME: xtime&wall_to_monotonic are set in timekeeping_init. */
-        read_persistent_clock(&xtime);
-        set_normalized_timespec(&wall_to_monotonic,
-                -xtime.tv_sec, -xtime.tv_nsec);
-
 #ifdef CONFIG_XTENSA_CALIBRATE_CCOUNT
         printk("Calibrating CPU frequency ");
         platform_calibrate_ccount();