1 files changed, 6 insertions, 178 deletions

diff --git a/arch/mips/kernel/i8253.c b/arch/mips/kernel/i8253.c
index 2392a7a296d..c5bc344fc74 100644
--- a/arch/mips/kernel/i8253.c
+++ b/arch/mips/kernel/i8253.c
@@ -3,209 +3,37 @@
  *
  */
 #include <linux/clockchips.h>
-#include <linux/init.h>
-#include <linux/interrupt.h>
-#include <linux/jiffies.h>
-#include <linux/module.h>
+#include <linux/i8253.h>
+#include <linux/export.h>
 #include <linux/smp.h>
-#include <linux/spinlock.h>
 #include <linux/irq.h>
 
-#include <asm/delay.h>
-#include <asm/i8253.h>
-#include <asm/io.h>
 #include <asm/time.h>
 
-DEFINE_RAW_SPINLOCK(i8253_lock);
-EXPORT_SYMBOL(i8253_lock);
-
-/*
- * Initialize the PIT timer.
- *
- * This is also called after resume to bring the PIT into operation again.
- */
-static void init_pit_timer(enum clock_event_mode mode,
-			   struct clock_event_device *evt)
-{
-	raw_spin_lock(&i8253_lock);
-
-	switch(mode) {
-	case CLOCK_EVT_MODE_PERIODIC:
-		/* binary, mode 2, LSB/MSB, ch 0 */
-		outb_p(0x34, PIT_MODE);
-		outb_p(LATCH & 0xff , PIT_CH0);	/* LSB */
-		outb(LATCH >> 8 , PIT_CH0);	/* MSB */
-		break;
-
-	case CLOCK_EVT_MODE_SHUTDOWN:
-	case CLOCK_EVT_MODE_UNUSED:
-		if (evt->mode == CLOCK_EVT_MODE_PERIODIC ||
-		    evt->mode == CLOCK_EVT_MODE_ONESHOT) {
-			outb_p(0x30, PIT_MODE);
-			outb_p(0, PIT_CH0);
-			outb_p(0, PIT_CH0);
-		}
-		break;
-
-	case CLOCK_EVT_MODE_ONESHOT:
-		/* One shot setup */
-		outb_p(0x38, PIT_MODE);
-		break;
-
-	case CLOCK_EVT_MODE_RESUME:
-		/* Nothing to do here */
-		break;
-	}
-	raw_spin_unlock(&i8253_lock);
-}
-
-/*
- * Program the next event in oneshot mode
- *
- * Delta is given in PIT ticks
- */
-static int pit_next_event(unsigned long delta, struct clock_event_device *evt)
-{
-	raw_spin_lock(&i8253_lock);
-	outb_p(delta & 0xff , PIT_CH0);	/* LSB */
-	outb(delta >> 8 , PIT_CH0);	/* MSB */
-	raw_spin_unlock(&i8253_lock);
-
-	return 0;
-}
-
-/*
- * On UP the PIT can serve all of the possible timer functions. On SMP systems
- * it can be solely used for the global tick.
- *
- * The profiling and update capabilites are switched off once the local apic is
- * registered. This mechanism replaces the previous #ifdef LOCAL_APIC -
- * !using_apic_timer decisions in do_timer_interrupt_hook()
- */
-static struct clock_event_device pit_clockevent = {
-	.name		= "pit",
-	.features	= CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
-	.set_mode	= init_pit_timer,
-	.set_next_event = pit_next_event,
-	.irq		= 0,
-};
-
 static irqreturn_t timer_interrupt(int irq, void *dev_id)
 {
-	pit_clockevent.event_handler(&pit_clockevent);
+	i8253_clockevent.event_handler(&i8253_clockevent);
 
 	return IRQ_HANDLED;
 }
 
 static struct irqaction irq0  = {
 	.handler = timer_interrupt,
-	.flags = IRQF_DISABLED | IRQF_NOBALANCING | IRQF_TIMER,
+	.flags = IRQF_NOBALANCING | IRQF_TIMER,
 	.name = "timer"
 };
 
-/*
- * Initialize the conversion factor and the min/max deltas of the clock event
- * structure and register the clock event source with the framework.
- */
 void __init setup_pit_timer(void)
 {
-	struct clock_event_device *cd = &pit_clockevent;
-	unsigned int cpu = smp_processor_id();
-
-	/*
-	 * Start pit with the boot cpu mask and make it global after the
-	 * IO_APIC has been initialized.
-	 */
-	cd->cpumask = cpumask_of(cpu);
-	clockevent_set_clock(cd, CLOCK_TICK_RATE);
-	cd->max_delta_ns = clockevent_delta2ns(0x7FFF, cd);
-	cd->min_delta_ns = clockevent_delta2ns(0xF, cd);
-	clockevents_register_device(cd);
-
+	clockevent_i8253_init(true);
 	setup_irq(0, &irq0);
 }
 
-/*
- * Since the PIT overflows every tick, its not very useful
- * to just read by itself. So use jiffies to emulate a free
- * running counter:
- */
-static cycle_t pit_read(struct clocksource *cs)
-{
-	unsigned long flags;
-	int count;
-	u32 jifs;
-	static int old_count;
-	static u32 old_jifs;
-
-	raw_spin_lock_irqsave(&i8253_lock, flags);
-	/*
-	 * Although our caller may have the read side of xtime_lock,
-	 * this is now a seqlock, and we are cheating in this routine
-	 * by having side effects on state that we cannot undo if
-	 * there is a collision on the seqlock and our caller has to
-	 * retry.  (Namely, old_jifs and old_count.)  So we must treat
-	 * jiffies as volatile despite the lock.  We read jiffies
-	 * before latching the timer count to guarantee that although
-	 * the jiffies value might be older than the count (that is,
-	 * the counter may underflow between the last point where
-	 * jiffies was incremented and the point where we latch the
-	 * count), it cannot be newer.
-	 */
-	jifs = jiffies;
-	outb_p(0x00, PIT_MODE);	/* latch the count ASAP */
-	count = inb_p(PIT_CH0);	/* read the latched count */
-	count |= inb_p(PIT_CH0) << 8;
-
-	/* VIA686a test code... reset the latch if count > max + 1 */
-	if (count > LATCH) {
-		outb_p(0x34, PIT_MODE);
-		outb_p(LATCH & 0xff, PIT_CH0);
-		outb(LATCH >> 8, PIT_CH0);
-		count = LATCH - 1;
-	}
-
-	/*
-	 * It's possible for count to appear to go the wrong way for a
-	 * couple of reasons:
-	 *
-	 *  1. The timer counter underflows, but we haven't handled the
-	 *     resulting interrupt and incremented jiffies yet.
-	 *  2. Hardware problem with the timer, not giving us continuous time,
-	 *     the counter does small "jumps" upwards on some Pentium systems,
-	 *     (see c't 95/10 page 335 for Neptun bug.)
-	 *
-	 * Previous attempts to handle these cases intelligently were
-	 * buggy, so we just do the simple thing now.
-	 */
-	if (count > old_count && jifs == old_jifs) {
-		count = old_count;
-	}
-	old_count = count;
-	old_jifs = jifs;
-
-	raw_spin_unlock_irqrestore(&i8253_lock, flags);
-
-	count = (LATCH - 1) - count;
-
-	return (cycle_t)(jifs * LATCH) + count;
-}
-
-static struct clocksource clocksource_pit = {
-	.name	= "pit",
-	.rating = 110,
-	.read	= pit_read,
-	.mask	= CLOCKSOURCE_MASK(32),
-	.mult	= 0,
-	.shift	= 20,
-};
-
 static int __init init_pit_clocksource(void)
 {
 	if (num_possible_cpus() > 1) /* PIT does not scale! */
 		return 0;
 
-	clocksource_pit.mult = clocksource_hz2mult(CLOCK_TICK_RATE, 20);
-	return clocksource_register(&clocksource_pit);
+	return clocksource_i8253_init();
 }
 arch_initcall(init_pit_clocksource);