[RFC/PATCH] Implement {read,update}_persistent_clock.

[RFC/PATCH] Implement {read,update}_persistent_clock.

[Tony Breeds]

With these functions implemented we cooperate better with the generic
timekeeping code.  This obsoletes the need for the timer sysdev as a bonus.

Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>

---

* Compile tested for arch/powerpc/configs/*_defconfig
* Booted on pSeries, iSeries, Cell and PS3
* Really needs booting on powermac and a quad G5 (hint hint)
* Should remove arch/powerpc/sysdev/timer.c at the same time.

 arch/powerpc/Kconfig         |    3 +
 arch/powerpc/kernel/time.c   |   58 ++++++++++-------------------------
 arch/powerpc/sysdev/Makefile |    5 ---
 3 files changed, 20 insertions(+), 46 deletions(-)

Index: working/arch/powerpc/Kconfig
===================================================================
--- working.orig/arch/powerpc/Kconfig
+++ working/arch/powerpc/Kconfig
@@ -21,6 +21,9 @@ config MMU
 	bool
 	default y
 
+config GENERIC_CMOS_UPDATE
+	def_bool y
+
 config GENERIC_HARDIRQS
 	bool
 	default y
Index: working/arch/powerpc/kernel/time.c
===================================================================
--- working.orig/arch/powerpc/kernel/time.c
+++ working/arch/powerpc/kernel/time.c
@@ -74,16 +74,11 @@
 #endif
 #include <asm/smp.h>
 
-/* keep track of when we need to update the rtc */
-time_t last_rtc_update;
 #ifdef CONFIG_PPC_ISERIES
 static unsigned long __initdata iSeries_recal_titan;
 static signed long __initdata iSeries_recal_tb;
 #endif
 
-/* The decrementer counts down by 128 every 128ns on a 601. */
-#define DECREMENTER_COUNT_601	(1000000000 / HZ)
-
 #define XSEC_PER_SEC (1024*1024)
 
 #ifdef CONFIG_PPC64
@@ -349,38 +344,7 @@ void udelay(unsigned long usecs)
 }
 EXPORT_SYMBOL(udelay);
 
-static __inline__ void timer_check_rtc(void)
-{
-        /*
-         * update the rtc when needed, this should be performed on the
-         * right fraction of a second. Half or full second ?
-         * Full second works on mk48t59 clocks, others need testing.
-         * Note that this update is basically only used through 
-         * the adjtimex system calls. Setting the HW clock in
-         * any other way is a /dev/rtc and userland business.
-         * This is still wrong by -0.5/+1.5 jiffies because of the
-         * timer interrupt resolution and possible delay, but here we 
-         * hit a quantization limit which can only be solved by higher
-         * resolution timers and decoupling time management from timer
-         * interrupts. This is also wrong on the clocks
-         * which require being written at the half second boundary.
-         * We should have an rtc call that only sets the minutes and
-         * seconds like on Intel to avoid problems with non UTC clocks.
-         */
-        if (ppc_md.set_rtc_time && ntp_synced() &&
-	    xtime.tv_sec - last_rtc_update >= 659 &&
-	    abs((xtime.tv_nsec/1000) - (1000000-1000000/HZ)) < 500000/HZ) {
-		struct rtc_time tm;
-		to_tm(xtime.tv_sec + 1 + timezone_offset, &tm);
-		tm.tm_year -= 1900;
-		tm.tm_mon -= 1;
-		if (ppc_md.set_rtc_time(&tm) == 0)
-			last_rtc_update = xtime.tv_sec + 1;
-		else
-			/* Try again one minute later */
-			last_rtc_update += 60;
-        }
-}
+
 
 /*
  * This version of gettimeofday has microsecond resolution.
@@ -688,7 +652,6 @@ void timer_interrupt(struct pt_regs * re
 			tb_last_jiffy = tb_next_jiffy;
 			do_timer(1);
 			timer_recalc_offset(tb_last_jiffy);
-			timer_check_rtc();
 		}
 		write_sequnlock(&xtime_lock);
 	}
@@ -800,11 +763,6 @@ int do_settimeofday(struct timespec *tv)
  	set_normalized_timespec(&xtime, new_sec, new_nsec);
 	set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec);
 
-	/* In case of a large backwards jump in time with NTP, we want the 
-	 * clock to be updated as soon as the PLL is again in lock.
-	 */
-	last_rtc_update = new_sec - 658;
-
 	ntp_clear();
 
 	new_xsec = xtime.tv_nsec;
@@ -880,12 +838,36 @@ void __init generic_calibrate_decr(void)
 #endif
 }
 
-unsigned long get_boot_time(void)
+int update_persistent_clock(struct timespec now)
 {
 	struct rtc_time tm;
 
-	if (ppc_md.get_boot_time)
-		return ppc_md.get_boot_time();
+	if (!ppc_md.set_rtc_time)
+		return 0;
+
+	to_tm(now.tv_sec + 1 + timezone_offset, &tm);
+	tm.tm_year -= 1900;
+	tm.tm_mon -= 1;
+
+	return ppc_md.set_rtc_time(&tm);
+}
+
+unsigned long read_persistent_clock(void)
+{
+	struct rtc_time tm;
+	static int first = 1;
+	unsigned long time = 0;
+
+	if (first) {
+		first = 0;
+		if (ppc_md.time_init)
+			timezone_offset = ppc_md.time_init();
+	}
+
+	/* get_boot_time() isn't guaranteed to be safe to call late */
+	if (system_state != SYSTEM_RUNNING && ppc_md.get_boot_time) {
+		return ppc_md.get_boot_time() -timezone_offset;
+	}
 	if (!ppc_md.get_rtc_time)
 		return 0;
 	ppc_md.get_rtc_time(&tm);
@@ -897,14 +879,10 @@ unsigned long get_boot_time(void)
 void __init time_init(void)
 {
 	unsigned long flags;
-	unsigned long tm = 0;
 	struct div_result res;
 	u64 scale, x;
 	unsigned shift;
 
-        if (ppc_md.time_init != NULL)
-                timezone_offset = ppc_md.time_init();
-
 	if (__USE_RTC()) {
 		/* 601 processor: dec counts down by 128 every 128ns */
 		ppc_tb_freq = 1000000000;
@@ -979,19 +957,14 @@ void __init time_init(void)
 	/* Save the current timebase to pretty up CONFIG_PRINTK_TIME */
 	boot_tb = get_tb();
 
-	tm = get_boot_time();
-
 	write_seqlock_irqsave(&xtime_lock, flags);
 
 	/* If platform provided a timezone (pmac), we correct the time */
         if (timezone_offset) {
 		sys_tz.tz_minuteswest = -timezone_offset / 60;
 		sys_tz.tz_dsttime = 0;
-		tm -= timezone_offset;
         }
 
-	xtime.tv_sec = tm;
-	xtime.tv_nsec = 0;
 	do_gtod.varp = &do_gtod.vars[0];
 	do_gtod.var_idx = 0;
 	do_gtod.varp->tb_orig_stamp = tb_last_jiffy;
@@ -1009,9 +982,6 @@ void __init time_init(void)
 
 	time_freq = 0;
 
-	last_rtc_update = xtime.tv_sec;
-	set_normalized_timespec(&wall_to_monotonic,
-	                        -xtime.tv_sec, -xtime.tv_nsec);
 	write_sequnlock_irqrestore(&xtime_lock, flags);
 
 	/* Not exact, but the timer interrupt takes care of this */
Index: working/arch/powerpc/sysdev/Makefile
===================================================================
--- working.orig/arch/powerpc/sysdev/Makefile
+++ working/arch/powerpc/sysdev/Makefile
@@ -20,11 +20,6 @@ obj-$(CONFIG_MV64X60)		+= $(mv64x60-y) m
 obj-$(CONFIG_RTC_DRV_CMOS)	+= rtc_cmos_setup.o
 obj-$(CONFIG_AXON_RAM)		+= axonram.o
 
-# contains only the suspend handler for time
-ifeq ($(CONFIG_RTC_CLASS),)
-obj-$(CONFIG_PM)		+= timer.o
-endif
-
 ifeq ($(CONFIG_PPC_MERGE),y)
 obj-$(CONFIG_PPC_INDIRECT_PCI)	+= indirect_pci.o
 obj-$(CONFIG_PPC_I8259)		+= i8259.o


Yours Tony

  linux.conf.au        http://linux.conf.au/ || http://lca2008.linux.org.au/
  Jan 28 - Feb 02 2008 The Australian Linux Technical Conference!

Re: [RFC/PATCH] Implement {read,update}_persistent_clock. v2

[Tony Breeds]

From: Tony Breeds <tony@bakeyournoodle.com>

Implement {read,update}_persistent_clock.

With these functions implemented we cooperate better with the generic
timekeeping code.  This obsoletes the need for the timer sysdev as a bonus.

Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>

---

Functionally is the same as previous version,  Just a few cleanups.

* Compile tested for arch/powerpc/configs/*_defconfig
* Booted on pSeries, iSeries, Cell and PS3
* Really needs booting on powermac and a quad G5 (hint hint)
* Should remove arch/powerpc/sysdev/timer.c

 arch/powerpc/Kconfig         |    3 +
 arch/powerpc/kernel/time.c   |   58 ++++++++++-------------------------
 arch/powerpc/sysdev/Makefile |    5 ---
 3 files changed, 20 insertions(+), 46 deletions(-)

Index: working/arch/powerpc/Kconfig
===================================================================
--- working.orig/arch/powerpc/Kconfig
+++ working/arch/powerpc/Kconfig
@@ -21,6 +21,9 @@ config MMU
 	bool
 	default y
 
+config GENERIC_CMOS_UPDATE
+	def_bool y
+
 config GENERIC_HARDIRQS
 	bool
 	default y
Index: working/arch/powerpc/kernel/time.c
===================================================================
--- working.orig/arch/powerpc/kernel/time.c
+++ working/arch/powerpc/kernel/time.c
@@ -74,16 +74,11 @@
 #endif
 #include <asm/smp.h>
 
-/* keep track of when we need to update the rtc */
-time_t last_rtc_update;
 #ifdef CONFIG_PPC_ISERIES
 static unsigned long __initdata iSeries_recal_titan;
 static signed long __initdata iSeries_recal_tb;
 #endif
 
-/* The decrementer counts down by 128 every 128ns on a 601. */
-#define DECREMENTER_COUNT_601	(1000000000 / HZ)
-
 #define XSEC_PER_SEC (1024*1024)
 
 #ifdef CONFIG_PPC64
@@ -349,39 +344,6 @@ void udelay(unsigned long usecs)
 }
 EXPORT_SYMBOL(udelay);
 
-static __inline__ void timer_check_rtc(void)
-{
-        /*
-         * update the rtc when needed, this should be performed on the
-         * right fraction of a second. Half or full second ?
-         * Full second works on mk48t59 clocks, others need testing.
-         * Note that this update is basically only used through 
-         * the adjtimex system calls. Setting the HW clock in
-         * any other way is a /dev/rtc and userland business.
-         * This is still wrong by -0.5/+1.5 jiffies because of the
-         * timer interrupt resolution and possible delay, but here we 
-         * hit a quantization limit which can only be solved by higher
-         * resolution timers and decoupling time management from timer
-         * interrupts. This is also wrong on the clocks
-         * which require being written at the half second boundary.
-         * We should have an rtc call that only sets the minutes and
-         * seconds like on Intel to avoid problems with non UTC clocks.
-         */
-        if (ppc_md.set_rtc_time && ntp_synced() &&
-	    xtime.tv_sec - last_rtc_update >= 659 &&
-	    abs((xtime.tv_nsec/1000) - (1000000-1000000/HZ)) < 500000/HZ) {
-		struct rtc_time tm;
-		to_tm(xtime.tv_sec + 1 + timezone_offset, &tm);
-		tm.tm_year -= 1900;
-		tm.tm_mon -= 1;
-		if (ppc_md.set_rtc_time(&tm) == 0)
-			last_rtc_update = xtime.tv_sec + 1;
-		else
-			/* Try again one minute later */
-			last_rtc_update += 60;
-        }
-}
-
 /*
  * This version of gettimeofday has microsecond resolution.
  */
@@ -688,7 +650,6 @@ void timer_interrupt(struct pt_regs * re
 			tb_last_jiffy = tb_next_jiffy;
 			do_timer(1);
 			timer_recalc_offset(tb_last_jiffy);
-			timer_check_rtc();
 		}
 		write_sequnlock(&xtime_lock);
 	}
@@ -800,11 +761,6 @@ int do_settimeofday(struct timespec *tv)
  	set_normalized_timespec(&xtime, new_sec, new_nsec);
 	set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec);
 
-	/* In case of a large backwards jump in time with NTP, we want the 
-	 * clock to be updated as soon as the PLL is again in lock.
-	 */
-	last_rtc_update = new_sec - 658;
-
 	ntp_clear();
 
 	new_xsec = xtime.tv_nsec;
@@ -880,12 +836,35 @@ void __init generic_calibrate_decr(void)
 #endif
 }
 
-unsigned long get_boot_time(void)
+int update_persistent_clock(struct timespec now)
+{
+	struct rtc_time tm;
+
+	if (!ppc_md.set_rtc_time)
+		return 0;
+
+	to_tm(now.tv_sec + 1 + timezone_offset, &tm);
+	tm.tm_year -= 1900;
+	tm.tm_mon -= 1;
+
+	return ppc_md.set_rtc_time(&tm);
+}
+
+unsigned long read_persistent_clock(void)
 {
 	struct rtc_time tm;
+	static int first = 1;
+
+	if (first) {
+		first = 0;
+		if (ppc_md.time_init)
+			timezone_offset = ppc_md.time_init();
+	}
 
-	if (ppc_md.get_boot_time)
-		return ppc_md.get_boot_time();
+	/* get_boot_time() isn't guaranteed to be safe to call late */
+	/* FIXME: is the a better check available here? */
+	if (system_state != SYSTEM_RUNNING && ppc_md.get_boot_time)
+		return ppc_md.get_boot_time() -timezone_offset;
 	if (!ppc_md.get_rtc_time)
 		return 0;
 	ppc_md.get_rtc_time(&tm);
@@ -897,14 +876,10 @@ unsigned long get_boot_time(void)
 void __init time_init(void)
 {
 	unsigned long flags;
-	unsigned long tm = 0;
 	struct div_result res;
 	u64 scale, x;
 	unsigned shift;
 
-        if (ppc_md.time_init != NULL)
-                timezone_offset = ppc_md.time_init();
-
 	if (__USE_RTC()) {
 		/* 601 processor: dec counts down by 128 every 128ns */
 		ppc_tb_freq = 1000000000;
@@ -979,19 +954,14 @@ void __init time_init(void)
 	/* Save the current timebase to pretty up CONFIG_PRINTK_TIME */
 	boot_tb = get_tb();
 
-	tm = get_boot_time();
-
 	write_seqlock_irqsave(&xtime_lock, flags);
 
 	/* If platform provided a timezone (pmac), we correct the time */
         if (timezone_offset) {
 		sys_tz.tz_minuteswest = -timezone_offset / 60;
 		sys_tz.tz_dsttime = 0;
-		tm -= timezone_offset;
         }
 
-	xtime.tv_sec = tm;
-	xtime.tv_nsec = 0;
 	do_gtod.varp = &do_gtod.vars[0];
 	do_gtod.var_idx = 0;
 	do_gtod.varp->tb_orig_stamp = tb_last_jiffy;
@@ -1009,9 +979,6 @@ void __init time_init(void)
 
 	time_freq = 0;
 
-	last_rtc_update = xtime.tv_sec;
-	set_normalized_timespec(&wall_to_monotonic,
-	                        -xtime.tv_sec, -xtime.tv_nsec);
 	write_sequnlock_irqrestore(&xtime_lock, flags);
 
 	/* Not exact, but the timer interrupt takes care of this */
Index: working/arch/powerpc/sysdev/Makefile
===================================================================
--- working.orig/arch/powerpc/sysdev/Makefile
+++ working/arch/powerpc/sysdev/Makefile
@@ -20,11 +20,6 @@ obj-$(CONFIG_MV64X60)		+= $(mv64x60-y) m
 obj-$(CONFIG_RTC_DRV_CMOS)	+= rtc_cmos_setup.o
 obj-$(CONFIG_AXON_RAM)		+= axonram.o
 
-# contains only the suspend handler for time
-ifeq ($(CONFIG_RTC_CLASS),)
-obj-$(CONFIG_PM)		+= timer.o
-endif
-
 ifeq ($(CONFIG_PPC_MERGE),y)
 obj-$(CONFIG_PPC_INDIRECT_PCI)	+= indirect_pci.o
 obj-$(CONFIG_PPC_I8259)		+= i8259.o

Re: [RFC/PATCH] Implement {read,update}_persistent_clock. v2

[Milton Miller]

On Tue Sep 11 18:17:46 EST 2007, Tony Breeds wrote:
> +unsigned long read_persistent_clock(void)
>  {
>         struct rtc_time tm;
> +       static int first = 1;
> +
> +       if (first) {
> +               first = 0;
> +               if (ppc_md.time_init)
> +                       timezone_offset = ppc_md.time_init();
> +       }
>
> -       if (ppc_md.get_boot_time)
> -               return ppc_md.get_boot_time();
> +       /* get_boot_time() isn't guaranteed to be safe to call late */
> +       /* FIXME: is the a better check available here? */
> +       if (system_state != SYSTEM_RUNNING && ppc_md.get_boot_time)
> +               return ppc_md.get_boot_time() -timezone_offset;
>         if (!ppc_md.get_rtc_time)
>                 return 0;
>         ppc_md.get_rtc_time(&tm);
>

Previously we called ppc_md.get_boot_time at most once.  How about 
moving the check for it into the if (first) block?

Have you tested with a platform that doesn't implement get_rtc_time?

milton

Re: [RFC/PATCH] Implement {read,update}_persistent_clock. v2

[Tony Breeds]

On Tue, Sep 11, 2007 at 09:34:13AM -0500, Milton Miller wrote:
 
> Previously we called ppc_md.get_boot_time at most once.  How about 
> moving the check for it into the if (first) block?

Yup on investigatiion it looks like moving it inside the "if (fist)" is
safe.
 
> Have you tested with a platform that doesn't implement get_rtc_time?

Well no I haven't.  AFAICT without my patch read_persistent_clock() is a
weak symbol that always returns 0.  So any platform that doesn't have a
ppc_md.get_boot_time() or ppc_md.get_rtc_time() will still get a 0 at
all the call sites.

I'll locate a machine and verify I'm not making things worse.

Yours Tony

  linux.conf.au        http://linux.conf.au/ || http://lca2008.linux.org.au/
  Jan 28 - Feb 02 2008 The Australian Linux Technical Conference!

Re: [RFC/PATCH] Implement {read,update}_persistent_clock.

[Gabriel Paubert]

On Tue, Sep 11, 2007 at 05:49:17PM +1000, Tony Breeds wrote:
> With these functions implemented we cooperate better with the generic
> timekeeping code.  This obsoletes the need for the timer sysdev as a bonus.

Looks fine, there is still the problem that most PPC RTC
seem to prefer update on the second boundary instead of
the half second used by Wintel clones.

> 
> Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
> 
> ---
> 
> * Compile tested for arch/powerpc/configs/*_defconfig
> * Booted on pSeries, iSeries, Cell and PS3
> * Really needs booting on powermac and a quad G5 (hint hint)
> * Should remove arch/powerpc/sysdev/timer.c at the same time.

Realistically this can only be tested with a running ntp
process which locks to a server.

> 
>  arch/powerpc/Kconfig         |    3 +
>  arch/powerpc/kernel/time.c   |   58 ++++++++++-------------------------
>  arch/powerpc/sysdev/Makefile |    5 ---
>  3 files changed, 20 insertions(+), 46 deletions(-)
> 
> Index: working/arch/powerpc/Kconfig
> ===================================================================
> --- working.orig/arch/powerpc/Kconfig
> +++ working/arch/powerpc/Kconfig
> @@ -21,6 +21,9 @@ config MMU
>  	bool
>  	default y
>  
> +config GENERIC_CMOS_UPDATE
> +	def_bool y
> +
>  config GENERIC_HARDIRQS
>  	bool
>  	default y
> Index: working/arch/powerpc/kernel/time.c
> ===================================================================
> --- working.orig/arch/powerpc/kernel/time.c
> +++ working/arch/powerpc/kernel/time.c
> @@ -74,16 +74,11 @@
>  #endif
>  #include <asm/smp.h>
>  
> -/* keep track of when we need to update the rtc */
> -time_t last_rtc_update;
>  #ifdef CONFIG_PPC_ISERIES
>  static unsigned long __initdata iSeries_recal_titan;
>  static signed long __initdata iSeries_recal_tb;
>  #endif
>  
> -/* The decrementer counts down by 128 every 128ns on a 601. */
> -#define DECREMENTER_COUNT_601	(1000000000 / HZ)
> -
>  #define XSEC_PER_SEC (1024*1024)
>  
>  #ifdef CONFIG_PPC64
> @@ -349,38 +344,7 @@ void udelay(unsigned long usecs)
>  }
>  EXPORT_SYMBOL(udelay);
>  
> -static __inline__ void timer_check_rtc(void)
> -{
> -        /*
> -         * update the rtc when needed, this should be performed on the
> -         * right fraction of a second. Half or full second ?
> -         * Full second works on mk48t59 clocks, others need testing.
> -         * Note that this update is basically only used through 
> -         * the adjtimex system calls. Setting the HW clock in
> -         * any other way is a /dev/rtc and userland business.
> -         * This is still wrong by -0.5/+1.5 jiffies because of the
> -         * timer interrupt resolution and possible delay, but here we 
> -         * hit a quantization limit which can only be solved by higher
> -         * resolution timers and decoupling time management from timer
> -         * interrupts. This is also wrong on the clocks
> -         * which require being written at the half second boundary.
> -         * We should have an rtc call that only sets the minutes and
> -         * seconds like on Intel to avoid problems with non UTC clocks.
> -         */
> -        if (ppc_md.set_rtc_time && ntp_synced() &&
> -	    xtime.tv_sec - last_rtc_update >= 659 &&
> -	    abs((xtime.tv_nsec/1000) - (1000000-1000000/HZ)) < 500000/HZ) {
> -		struct rtc_time tm;
> -		to_tm(xtime.tv_sec + 1 + timezone_offset, &tm);
> -		tm.tm_year -= 1900;
> -		tm.tm_mon -= 1;
> -		if (ppc_md.set_rtc_time(&tm) == 0)
> -			last_rtc_update = xtime.tv_sec + 1;
> -		else
> -			/* Try again one minute later */
> -			last_rtc_update += 60;
> -        }
> -}
> +
>  
>  /*
>   * This version of gettimeofday has microsecond resolution.
> @@ -688,7 +652,6 @@ void timer_interrupt(struct pt_regs * re
>  			tb_last_jiffy = tb_next_jiffy;
>  			do_timer(1);
>  			timer_recalc_offset(tb_last_jiffy);
> -			timer_check_rtc();
>  		}
>  		write_sequnlock(&xtime_lock);
>  	}
> @@ -800,11 +763,6 @@ int do_settimeofday(struct timespec *tv)
>   	set_normalized_timespec(&xtime, new_sec, new_nsec);
>  	set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec);
>  
> -	/* In case of a large backwards jump in time with NTP, we want the 
> -	 * clock to be updated as soon as the PLL is again in lock.
> -	 */
> -	last_rtc_update = new_sec - 658;
> -
>  	ntp_clear();
>  
>  	new_xsec = xtime.tv_nsec;
> @@ -880,12 +838,36 @@ void __init generic_calibrate_decr(void)
>  #endif
>  }
>  
> -unsigned long get_boot_time(void)
> +int update_persistent_clock(struct timespec now)
>  {
>  	struct rtc_time tm;
>  
> -	if (ppc_md.get_boot_time)
> -		return ppc_md.get_boot_time();
> +	if (!ppc_md.set_rtc_time)
> +		return 0;
> +
> +	to_tm(now.tv_sec + 1 + timezone_offset, &tm);
> +	tm.tm_year -= 1900;
> +	tm.tm_mon -= 1;
> +
> +	return ppc_md.set_rtc_time(&tm);
> +}
> +
> +unsigned long read_persistent_clock(void)
> +{
> +	struct rtc_time tm;
> +	static int first = 1;
> +	unsigned long time = 0;
> +
> +	if (first) {
> +		first = 0;
> +		if (ppc_md.time_init)
> +			timezone_offset = ppc_md.time_init();
> +	}
> +
> +	/* get_boot_time() isn't guaranteed to be safe to call late */
> +	if (system_state != SYSTEM_RUNNING && ppc_md.get_boot_time) {
> +		return ppc_md.get_boot_time() -timezone_offset;
> +	}
>  	if (!ppc_md.get_rtc_time)
>  		return 0;
>  	ppc_md.get_rtc_time(&tm);
> @@ -897,14 +879,10 @@ unsigned long get_boot_time(void)
>  void __init time_init(void)
>  {
>  	unsigned long flags;
> -	unsigned long tm = 0;
>  	struct div_result res;
>  	u64 scale, x;
>  	unsigned shift;
>  
> -        if (ppc_md.time_init != NULL)
> -                timezone_offset = ppc_md.time_init();
> -
>  	if (__USE_RTC()) {
>  		/* 601 processor: dec counts down by 128 every 128ns */
>  		ppc_tb_freq = 1000000000;
> @@ -979,19 +957,14 @@ void __init time_init(void)
>  	/* Save the current timebase to pretty up CONFIG_PRINTK_TIME */
>  	boot_tb = get_tb();
>  
> -	tm = get_boot_time();
> -
>  	write_seqlock_irqsave(&xtime_lock, flags);
>  
>  	/* If platform provided a timezone (pmac), we correct the time */
>          if (timezone_offset) {
>  		sys_tz.tz_minuteswest = -timezone_offset / 60;
>  		sys_tz.tz_dsttime = 0;
> -		tm -= timezone_offset;
>          }
>  
> -	xtime.tv_sec = tm;
> -	xtime.tv_nsec = 0;
>  	do_gtod.varp = &do_gtod.vars[0];
>  	do_gtod.var_idx = 0;
>  	do_gtod.varp->tb_orig_stamp = tb_last_jiffy;
> @@ -1009,9 +982,6 @@ void __init time_init(void)
>  
>  	time_freq = 0;
>  
> -	last_rtc_update = xtime.tv_sec;
> -	set_normalized_timespec(&wall_to_monotonic,
> -	                        -xtime.tv_sec, -xtime.tv_nsec);
>  	write_sequnlock_irqrestore(&xtime_lock, flags);
>  
>  	/* Not exact, but the timer interrupt takes care of this */
> Index: working/arch/powerpc/sysdev/Makefile
> ===================================================================
> --- working.orig/arch/powerpc/sysdev/Makefile
> +++ working/arch/powerpc/sysdev/Makefile
> @@ -20,11 +20,6 @@ obj-$(CONFIG_MV64X60)		+= $(mv64x60-y) m
>  obj-$(CONFIG_RTC_DRV_CMOS)	+= rtc_cmos_setup.o
>  obj-$(CONFIG_AXON_RAM)		+= axonram.o
>  
> -# contains only the suspend handler for time
> -ifeq ($(CONFIG_RTC_CLASS),)
> -obj-$(CONFIG_PM)		+= timer.o
> -endif
> -
>  ifeq ($(CONFIG_PPC_MERGE),y)
>  obj-$(CONFIG_PPC_INDIRECT_PCI)	+= indirect_pci.o
>  obj-$(CONFIG_PPC_I8259)		+= i8259.o
> 
> 
> Yours Tony
> 
>   linux.conf.au        http://linux.conf.au/ || http://lca2008.linux.org.au/
>   Jan 28 - Feb 02 2008 The Australian Linux Technical Conference!
> 
> _______________________________________________
> Linuxppc-dev mailing list
> Linuxppc-dev@ozlabs.org
> https://ozlabs.org/mailman/listinfo/linuxppc-dev