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Diffstat (limited to 'arch/i386/kernel/i8253_32.c')
-rw-r--r--arch/i386/kernel/i8253_32.c206
1 files changed, 0 insertions, 206 deletions
diff --git a/arch/i386/kernel/i8253_32.c b/arch/i386/kernel/i8253_32.c
deleted file mode 100644
index 6d839f2f1b1a..000000000000
--- a/arch/i386/kernel/i8253_32.c
+++ /dev/null
@@ -1,206 +0,0 @@
-/*
- * i8253.c 8253/PIT functions
- *
- */
-#include <linux/clockchips.h>
-#include <linux/init.h>
-#include <linux/interrupt.h>
-#include <linux/jiffies.h>
-#include <linux/module.h>
-#include <linux/spinlock.h>
-
-#include <asm/smp.h>
-#include <asm/delay.h>
-#include <asm/i8253.h>
-#include <asm/io.h>
-#include <asm/timer.h>
-
-DEFINE_SPINLOCK(i8253_lock);
-EXPORT_SYMBOL(i8253_lock);
-
-/*
- * HPET replaces the PIT, when enabled. So we need to know, which of
- * the two timers is used
- */
-struct clock_event_device *global_clock_event;
-
-/*
- * 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)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&i8253_lock, flags);
-
- 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;
- }
- spin_unlock_irqrestore(&i8253_lock, flags);
-}
-
-/*
- * 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)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&i8253_lock, flags);
- outb_p(delta & 0xff , PIT_CH0); /* LSB */
- outb(delta >> 8 , PIT_CH0); /* MSB */
- spin_unlock_irqrestore(&i8253_lock, flags);
-
- 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()
- */
-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,
- .shift = 32,
- .irq = 0,
-};
-
-/*
- * 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)
-{
- /*
- * Start pit with the boot cpu mask and make it global after the
- * IO_APIC has been initialized.
- */
- pit_clockevent.cpumask = cpumask_of_cpu(smp_processor_id());
- pit_clockevent.mult = div_sc(CLOCK_TICK_RATE, NSEC_PER_SEC, 32);
- pit_clockevent.max_delta_ns =
- clockevent_delta2ns(0x7FFF, &pit_clockevent);
- pit_clockevent.min_delta_ns =
- clockevent_delta2ns(0xF, &pit_clockevent);
- clockevents_register_device(&pit_clockevent);
- global_clock_event = &pit_clockevent;
-}
-
-/*
- * 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(void)
-{
- unsigned long flags;
- int count;
- u32 jifs;
- static int old_count;
- static u32 old_jifs;
-
- 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;
-
- 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);
-}
-arch_initcall(init_pit_clocksource);