diff options
Diffstat (limited to 'arch/x86/kernel/i8253.c')
| -rw-r--r-- | arch/x86/kernel/i8253.c | 68 |
1 files changed, 33 insertions, 35 deletions
diff --git a/arch/x86/kernel/i8253.c b/arch/x86/kernel/i8253.c index 10f92fb532f3..3475440baa54 100644 --- a/arch/x86/kernel/i8253.c +++ b/arch/x86/kernel/i8253.c @@ -3,17 +3,17 @@ * */ #include <linux/clockchips.h> -#include <linux/init.h> #include <linux/interrupt.h> +#include <linux/spinlock.h> #include <linux/jiffies.h> #include <linux/module.h> -#include <linux/spinlock.h> +#include <linux/delay.h> +#include <linux/init.h> +#include <linux/io.h> -#include <asm/smp.h> -#include <asm/delay.h> #include <asm/i8253.h> -#include <asm/io.h> #include <asm/hpet.h> +#include <asm/smp.h> DEFINE_SPINLOCK(i8253_lock); EXPORT_SYMBOL(i8253_lock); @@ -40,7 +40,7 @@ static void init_pit_timer(enum clock_event_mode mode, { spin_lock(&i8253_lock); - switch(mode) { + switch (mode) { case CLOCK_EVT_MODE_PERIODIC: /* binary, mode 2, LSB/MSB, ch 0 */ outb_pit(0x34, PIT_MODE); @@ -95,7 +95,7 @@ static int pit_next_event(unsigned long delta, struct clock_event_device *evt) * 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 = { +static struct clock_event_device pit_ce = { .name = "pit", .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, .set_mode = init_pit_timer, @@ -114,15 +114,13 @@ 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(smp_processor_id()); - pit_clockevent.mult = div_sc(CLOCK_TICK_RATE, NSEC_PER_SEC, - pit_clockevent.shift); - 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; + pit_ce.cpumask = cpumask_of(smp_processor_id()); + pit_ce.mult = div_sc(CLOCK_TICK_RATE, NSEC_PER_SEC, pit_ce.shift); + pit_ce.max_delta_ns = clockevent_delta2ns(0x7FFF, &pit_ce); + pit_ce.min_delta_ns = clockevent_delta2ns(0xF, &pit_ce); + + clockevents_register_device(&pit_ce); + global_clock_event = &pit_ce; } #ifndef CONFIG_X86_64 @@ -133,11 +131,11 @@ void __init setup_pit_timer(void) */ static cycle_t pit_read(void) { + static int old_count; + static u32 old_jifs; unsigned long flags; int count; u32 jifs; - static int old_count; - static u32 old_jifs; spin_lock_irqsave(&i8253_lock, flags); /* @@ -179,9 +177,9 @@ static cycle_t pit_read(void) * Previous attempts to handle these cases intelligently were * buggy, so we just do the simple thing now. */ - if (count > old_count && jifs == old_jifs) { + if (count > old_count && jifs == old_jifs) count = old_count; - } + old_count = count; old_jifs = jifs; @@ -192,13 +190,13 @@ static cycle_t pit_read(void) 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 struct clocksource pit_cs = { + .name = "pit", + .rating = 110, + .read = pit_read, + .mask = CLOCKSOURCE_MASK(32), + .mult = 0, + .shift = 20, }; static void pit_disable_clocksource(void) @@ -206,9 +204,9 @@ static void pit_disable_clocksource(void) /* * Use mult to check whether it is registered or not */ - if (clocksource_pit.mult) { - clocksource_unregister(&clocksource_pit); - clocksource_pit.mult = 0; + if (pit_cs.mult) { + clocksource_unregister(&pit_cs); + pit_cs.mult = 0; } } @@ -222,13 +220,13 @@ static int __init init_pit_clocksource(void) * - when local APIC timer is active (PIT is switched off) */ if (num_possible_cpus() > 1 || is_hpet_enabled() || - pit_clockevent.mode != CLOCK_EVT_MODE_PERIODIC) + pit_ce.mode != CLOCK_EVT_MODE_PERIODIC) return 0; - clocksource_pit.mult = clocksource_hz2mult(CLOCK_TICK_RATE, - clocksource_pit.shift); - return clocksource_register(&clocksource_pit); + pit_cs.mult = clocksource_hz2mult(CLOCK_TICK_RATE, pit_cs.shift); + + return clocksource_register(&pit_cs); } arch_initcall(init_pit_clocksource); -#endif +#endif /* !CONFIG_X86_64 */ |