cris: Convert cris to use read/update_persistent_clock

This patch converts the cris architecture to use the generic
read_persistent_clock and update_persistent_clock interfaces, reducing
the amount of arch specific code we have to maintain, and allowing for
further cleanups in the future.

I have not built or tested this patch, so help from arch maintainers
would be appreciated.

Signed-off-by: John Stultz <johnstul@us.ibm.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <1267675049-12337-14-git-send-email-johnstul@us.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

4 files changed, 18 insertions, 82 deletions

diff --git a/arch/cris/Kconfig b/arch/cris/Kconfig
index 059eac6abda1..e25bf4440b51 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 31ca1418d5a7..30adae594aef 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 b1920d8de403..1ee0e1010228 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 a05dd31f3efb..c72730d20ef6 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