[RFC][PATCH 9/12] generic timeofday i386 arch specific changes, part 5

[john stultz <johnstul@us.ibm.com>]

All,
	The conversion of i386 to use the generic timeofday subsystem has been
split into 6 parts. This patch, the fifth of six, converts the i386 arch
to use the generic timeofday subsystem.

It applies on top of my timeofday-arch-i386-part4 patch. 

thanks
-john

 arch/i386/Kconfig            |    4 
 arch/i386/kernel/Makefile    |    1 
 arch/i386/kernel/time.c      |  219 ++++++-------------------------------------
 arch/i386/lib/delay.c        |   16 ++-
 include/asm-i386/timeofday.h |    4 
 include/asm-i386/timer.h     |   57 -----------
 6 files changed, 55 insertions(+), 246 deletions(-)

linux-2.6.14-rc5-mm1_timeofday-arch-i386-part5_B9.patch
============================================
diff --git a/arch/i386/Kconfig b/arch/i386/Kconfig
--- a/arch/i386/Kconfig
+++ b/arch/i386/Kconfig
@@ -14,6 +14,10 @@ config X86_32
 	  486, 586, Pentiums, and various instruction-set-compatible chips by
 	  AMD, Cyrix, and others.
 
+config GENERIC_TIME
+	bool
+	default y
+
 config SEMAPHORE_SLEEPERS
 	bool
 	default y
diff --git a/arch/i386/kernel/Makefile b/arch/i386/kernel/Makefile
--- a/arch/i386/kernel/Makefile
+++ b/arch/i386/kernel/Makefile
@@ -10,7 +10,6 @@ obj-y	:= process.o semaphore.o signal.o 
 		doublefault.o quirks.o i8237.o i8253.o tsc.o
 
 obj-y				+= cpu/
-obj-y				+= timers/
 obj-$(CONFIG_ACPI)		+= acpi/
 obj-$(CONFIG_X86_BIOS_REBOOT)	+= reboot.o
 obj-$(CONFIG_MCA)		+= mca.o
diff --git a/arch/i386/kernel/time.c b/arch/i386/kernel/time.c
--- a/arch/i386/kernel/time.c
+++ b/arch/i386/kernel/time.c
@@ -56,6 +56,7 @@
 #include <asm/uaccess.h>
 #include <asm/processor.h>
 #include <asm/timer.h>
+#include <asm/timeofday.h>
 
 #include "mach_time.h"
 
@@ -82,8 +83,6 @@ extern unsigned long wall_jiffies;
 DEFINE_SPINLOCK(rtc_lock);
 EXPORT_SYMBOL(rtc_lock);
 
-struct timer_opts *cur_timer __read_mostly = &timer_none;
-
 /*
  * This is a special lock that is owned by the CPU and holds the index
  * register we are working with.  It is required for NMI access to the
@@ -113,99 +112,19 @@ void rtc_cmos_write(unsigned char val, u
 }
 EXPORT_SYMBOL(rtc_cmos_write);
 
-/*
- * This version of gettimeofday has microsecond resolution
- * and better than microsecond precision on fast x86 machines with TSC.
- */
-void do_gettimeofday(struct timeval *tv)
-{
-	unsigned long seq;
-	unsigned long usec, sec;
-	unsigned long max_ntp_tick;
-
-	do {
-		unsigned long lost;
-
-		seq = read_seqbegin(&xtime_lock);
-
-		usec = cur_timer->get_offset();
-		lost = jiffies - wall_jiffies;
-
-		/*
-		 * If time_adjust is negative then NTP is slowing the clock
-		 * so make sure not to go into next possible interval.
-		 * Better to lose some accuracy than have time go backwards..
-		 */
-		if (unlikely(time_adjust < 0)) {
-			max_ntp_tick = (USEC_PER_SEC / HZ) - tickadj;
-			usec = min(usec, max_ntp_tick);
-
-			if (lost)
-				usec += lost * max_ntp_tick;
-		}
-		else if (unlikely(lost))
-			usec += lost * (USEC_PER_SEC / HZ);
-
-		sec = xtime.tv_sec;
-		usec += (xtime.tv_nsec / 1000);
-	} while (read_seqretry(&xtime_lock, seq));
-
-	while (usec >= 1000000) {
-		usec -= 1000000;
-		sec++;
-	}
-
-	tv->tv_sec = sec;
-	tv->tv_usec = usec;
-}
-
-EXPORT_SYMBOL(do_gettimeofday);
-
-int do_settimeofday(struct timespec *tv)
-{
-	time_t wtm_sec, sec = tv->tv_sec;
-	long wtm_nsec, nsec = tv->tv_nsec;
-
-	if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC)
-		return -EINVAL;
-
-	write_seqlock_irq(&xtime_lock);
-	/*
-	 * This is revolting. We need to set "xtime" correctly. However, the
-	 * value in this location is the value at the most recent update of
-	 * wall time.  Discover what correction gettimeofday() would have
-	 * made, and then undo it!
-	 */
-	nsec -= cur_timer->get_offset() * NSEC_PER_USEC;
-	nsec -= (jiffies - wall_jiffies) * TICK_NSEC;
-
-	wtm_sec  = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec);
-	wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec);
-
-	set_normalized_timespec(&xtime, sec, nsec);
-	set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec);
-
-	ntp_clear();
-	write_sequnlock_irq(&xtime_lock);
-	clock_was_set();
-	return 0;
-}
-
-EXPORT_SYMBOL(do_settimeofday);
-
 static int set_rtc_mmss(unsigned long nowtime)
 {
 	int retval;
-
-	WARN_ON(irqs_disabled());
+	unsigned long flags;
 
 	/* gets recalled with irq locally disabled */
-	spin_lock_irq(&rtc_lock);
+	/* XXX - does irqsave resolve this? -johnstul */
+	spin_lock_irqsave(&rtc_lock, flags);
 	if (efi_enabled)
 		retval = efi_set_rtc_mmss(nowtime);
 	else
 		retval = mach_set_rtc_mmss(nowtime);
-	spin_unlock_irq(&rtc_lock);
+	spin_unlock_irqrestore(&rtc_lock, flags);
 
 	return retval;
 }
@@ -213,16 +132,6 @@ static int set_rtc_mmss(unsigned long no
 
 int timer_ack;
 
-/* monotonic_clock(): returns # of nanoseconds passed since time_init()
- *		Note: This function is required to return accurate
- *		time even in the absence of multiple timer ticks.
- */
-unsigned long long monotonic_clock(void)
-{
-	return cur_timer->monotonic_clock();
-}
-EXPORT_SYMBOL(monotonic_clock);
-
 #if defined(CONFIG_SMP) && defined(CONFIG_FRAME_POINTER)
 unsigned long profile_pc(struct pt_regs *regs)
 {
@@ -237,11 +146,21 @@ EXPORT_SYMBOL(profile_pc);
 #endif
 
 /*
- * timer_interrupt() needs to keep up the real-time clock,
- * as well as call the "do_timer()" routine every clocktick
+ * This is the same as the above, except we _also_ save the current
+ * Time Stamp Counter value at the time of the timer interrupt, so that
+ * we later on can estimate the time of day more exactly.
  */
-static inline void do_timer_interrupt(int irq, struct pt_regs *regs)
+irqreturn_t timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
 {
+	/*
+	 * Here we are in the timer irq handler. We just have irqs locally
+	 * disabled but we don't know if the timer_bh is running on the other
+	 * CPU. We need to avoid to SMP race with it. NOTE: we don' t need
+	 * the irq version of write_lock because as just said we have irq
+	 * locally disabled. -arca
+	 */
+	write_seqlock(&xtime_lock);
+
 #ifdef CONFIG_X86_IO_APIC
 	if (timer_ack) {
 		/*
@@ -274,27 +193,6 @@ static inline void do_timer_interrupt(in
 		irq = inb_p( 0x61 );	/* read the current state */
 		outb_p( irq|0x80, 0x61 );	/* reset the IRQ */
 	}
-}
-
-/*
- * This is the same as the above, except we _also_ save the current
- * Time Stamp Counter value at the time of the timer interrupt, so that
- * we later on can estimate the time of day more exactly.
- */
-irqreturn_t timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
-{
-	/*
-	 * Here we are in the timer irq handler. We just have irqs locally
-	 * disabled but we don't know if the timer_bh is running on the other
-	 * CPU. We need to avoid to SMP race with it. NOTE: we don' t need
-	 * the irq version of write_lock because as just said we have irq
-	 * locally disabled. -arca
-	 */
-	write_seqlock(&xtime_lock);
-
-	cur_timer->mark_offset();
- 
-	do_timer_interrupt(irq, regs);
 
 	write_sequnlock(&xtime_lock);
 	return IRQ_HANDLED;
@@ -318,58 +216,37 @@ unsigned long get_cmos_time(void)
 }
 EXPORT_SYMBOL(get_cmos_time);
 
-static void sync_cmos_clock(unsigned long dummy);
-
-static DEFINE_TIMER(sync_cmos_timer, sync_cmos_clock, 0, 0);
-
-static void sync_cmos_clock(unsigned long dummy)
+/* arch specific timeofday hooks */
+nsec_t read_persistent_clock(void)
 {
-	struct timeval now, next;
-	int fail = 1;
+	return (nsec_t)get_cmos_time() * NSEC_PER_SEC;
+}
 
+void sync_persistent_clock(struct timespec ts)
+{
+	static unsigned long last_rtc_update;
 	/*
 	 * 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.
-	 * This code is run on a timer.  If the clock is set, that timer
-	 * may not expire at the correct time.  Thus, we adjust...
 	 */
-	if (!ntp_synced())
-		/*
-		 * Not synced, exit, do not restart a timer (if one is
-		 * running, let it run out).
-		 */
+	if (ts.tv_sec <= last_rtc_update + 660)
 		return;
 
-	do_gettimeofday(&now);
-	if (now.tv_usec >= USEC_AFTER - ((unsigned) TICK_SIZE) / 2 &&
-	    now.tv_usec <= USEC_BEFORE + ((unsigned) TICK_SIZE) / 2)
-		fail = set_rtc_mmss(now.tv_sec);
-
-	next.tv_usec = USEC_AFTER - now.tv_usec;
-	if (next.tv_usec <= 0)
-		next.tv_usec += USEC_PER_SEC;
-
-	if (!fail)
-		next.tv_sec = 659;
-	else
-		next.tv_sec = 0;
-
-	if (next.tv_usec >= USEC_PER_SEC) {
-		next.tv_sec++;
-		next.tv_usec -= USEC_PER_SEC;
+	if((ts.tv_nsec / 1000) >= USEC_AFTER - ((unsigned) TICK_SIZE) / 2 &&
+		(ts.tv_nsec / 1000) <= USEC_BEFORE + ((unsigned) TICK_SIZE) / 2) {
+		/* horrible...FIXME */
+		if (set_rtc_mmss(ts.tv_sec) == 0)
+			last_rtc_update = ts.tv_sec;
+		else
+			last_rtc_update = ts.tv_sec - 600; /* do it again in 60 s */
 	}
-	mod_timer(&sync_cmos_timer, jiffies + timeval_to_jiffies(&next));
 }
 
-void notify_arch_cmos_timer(void)
-{
-	mod_timer(&sync_cmos_timer, jiffies + 1);
-}
+
 
 static long clock_cmos_diff, sleep_start;
 
-static struct timer_opts *last_timer;
 static int timer_suspend(struct sys_device *dev, pm_message_t state)
 {
 	/*
@@ -378,16 +255,11 @@ static int timer_suspend(struct sys_devi
 	clock_cmos_diff = -get_cmos_time();
 	clock_cmos_diff += get_seconds();
 	sleep_start = get_cmos_time();
-	last_timer = cur_timer;
-	cur_timer = &timer_none;
-	if (last_timer->suspend)
-		last_timer->suspend(state);
 	return 0;
 }
 
 static int timer_resume(struct sys_device *dev)
 {
-	unsigned long flags;
 	unsigned long sec;
 	unsigned long sleep_length;
 
@@ -397,16 +269,8 @@ static int timer_resume(struct sys_devic
 #endif
 	sec = get_cmos_time() + clock_cmos_diff;
 	sleep_length = (get_cmos_time() - sleep_start) * HZ;
-	write_seqlock_irqsave(&xtime_lock, flags);
-	xtime.tv_sec = sec;
-	xtime.tv_nsec = 0;
-	write_sequnlock_irqrestore(&xtime_lock, flags);
 	jiffies += sleep_length;
 	wall_jiffies += sleep_length;
-	if (last_timer->resume)
-		last_timer->resume();
-	cur_timer = last_timer;
-	last_timer = NULL;
 	touch_softlockup_watchdog();
 	return 0;
 }
@@ -439,17 +303,10 @@ extern void (*late_time_init)(void);
 /* Duplicate of time_init() below, with hpet_enable part added */
 static void __init hpet_time_init(void)
 {
-	xtime.tv_sec = get_cmos_time();
-	xtime.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);
-	set_normalized_timespec(&wall_to_monotonic,
-		-xtime.tv_sec, -xtime.tv_nsec);
-
 	if ((hpet_enable() >= 0) && hpet_use_timer) {
 		printk("Using HPET for base-timer\n");
 	}
 
-	cur_timer = select_timer();
-	printk(KERN_INFO "Using %s for high-res timesource\n",cur_timer->name);
 
 	time_init_hook();
 
@@ -472,14 +329,6 @@ void __init time_init(void)
 		return;
 	}
 #endif
-	xtime.tv_sec = get_cmos_time();
-	xtime.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);
-	set_normalized_timespec(&wall_to_monotonic,
-		-xtime.tv_sec, -xtime.tv_nsec);
-
-	cur_timer = select_timer();
-	printk(KERN_INFO "Using %s for high-res timesource\n",cur_timer->name);
-
 	time_init_hook();
 
 #ifdef CONFIG_X86_LOCAL_APIC
diff --git a/arch/i386/lib/delay.c b/arch/i386/lib/delay.c
--- a/arch/i386/lib/delay.c
+++ b/arch/i386/lib/delay.c
@@ -13,6 +13,7 @@
 #include <linux/config.h>
 #include <linux/sched.h>
 #include <linux/delay.h>
+#include <linux/timeofday.h>
 #include <linux/module.h>
 #include <asm/processor.h>
 #include <asm/delay.h>
@@ -22,11 +23,20 @@
 #include <asm/smp.h>
 #endif
 
-extern struct timer_opts* timer;
-
+/* XXX - For now just use a simple loop delay
+ *  This has cpufreq issues, but so did the old method.
+ */
 void __delay(unsigned long loops)
 {
-	cur_timer->delay(loops);
+	int d0;
+	__asm__ __volatile__(
+		"\tjmp 1f\n"
+		".align 16\n"
+		"1:\tjmp 2f\n"
+		".align 16\n"
+		"2:\tdecl %0\n\tjns 2b"
+		:"=&a" (d0)
+		:"0" (loops));
 }
 
 inline void __const_udelay(unsigned long xloops)
diff --git a/include/asm-i386/timeofday.h b/include/asm-i386/timeofday.h
new file mode 100644
--- /dev/null
+++ b/include/asm-i386/timeofday.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_I386_TIMEOFDAY_H
+#define _ASM_I386_TIMEOFDAY_H
+#include <asm-generic/timeofday.h>
+#endif
diff --git a/include/asm-i386/timer.h b/include/asm-i386/timer.h
--- a/include/asm-i386/timer.h
+++ b/include/asm-i386/timer.h
@@ -3,68 +3,11 @@
 #include <linux/init.h>
 #include <linux/pm.h>
 
-/**
- * struct timer_ops - used to define a timer source
- *
- * @name: name of the timer.
- * @init: Probes and initializes the timer. Takes clock= override 
- *        string as an argument. Returns 0 on success, anything else
- *        on failure.
- * @mark_offset: called by the timer interrupt.
- * @get_offset:  called by gettimeofday(). Returns the number of microseconds
- *               since the last timer interupt.
- * @monotonic_clock: returns the number of nanoseconds since the init of the
- *                   timer.
- * @delay: delays this many clock cycles.
- */
-struct timer_opts {
-	char* name;
-	void (*mark_offset)(void);
-	unsigned long (*get_offset)(void);
-	unsigned long long (*monotonic_clock)(void);
-	void (*delay)(unsigned long);
-	unsigned long (*read_timer)(void);
-	int (*suspend)(pm_message_t state);
-	int (*resume)(void);
-};
-
-struct init_timer_opts {
-	int (*init)(char *override);
-	struct timer_opts *opts;
-};
-
 #define TICK_SIZE (tick_nsec / 1000)
-
-extern struct timer_opts* __init select_timer(void);
-extern void clock_fallback(void);
 void setup_pit_timer(void);
-
 /* Modifiers for buggy PIT handling */
-
 extern int pit_latch_buggy;
-
-extern struct timer_opts *cur_timer;
 extern int timer_ack;
-
-/* list of externed timers */
-extern struct timer_opts timer_none;
-extern struct timer_opts timer_pit;
-extern struct init_timer_opts timer_pit_init;
-extern struct init_timer_opts timer_tsc_init;
-#ifdef CONFIG_X86_CYCLONE_TIMER
-extern struct init_timer_opts timer_cyclone_init;
-#endif
-
-extern unsigned long calibrate_tsc(void);
-extern unsigned long read_timer_tsc(void);
-extern void init_cpu_khz(void);
 extern int recalibrate_cpu_khz(void);
-#ifdef CONFIG_HPET_TIMER
-extern struct init_timer_opts timer_hpet_init;
-extern unsigned long calibrate_tsc_hpet(unsigned long *tsc_hpet_quotient_ptr);
-#endif
 
-#ifdef CONFIG_X86_PM_TIMER
-extern struct init_timer_opts timer_pmtmr_init;
-#endif
 #endif


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