diff options
Diffstat (limited to 'arch/sparc/kernel/time_32.c')
-rw-r--r-- | arch/sparc/kernel/time_32.c | 215 |
1 files changed, 176 insertions, 39 deletions
diff --git a/arch/sparc/kernel/time_32.c b/arch/sparc/kernel/time_32.c index 68e0284bf3f3..89e890bc0941 100644 --- a/arch/sparc/kernel/time_32.c +++ b/arch/sparc/kernel/time_32.c @@ -26,6 +26,8 @@ #include <linux/rtc.h> #include <linux/rtc/m48t59.h> #include <linux/timex.h> +#include <linux/clocksource.h> +#include <linux/clockchips.h> #include <linux/init.h> #include <linux/pci.h> #include <linux/ioport.h> @@ -44,9 +46,21 @@ #include <asm/page.h> #include <asm/pcic.h> #include <asm/irq_regs.h> +#include <asm/setup.h> #include "irq.h" +static __cacheline_aligned_in_smp DEFINE_SEQLOCK(timer_cs_lock); +static __volatile__ u64 timer_cs_internal_counter = 0; +static char timer_cs_enabled = 0; + +static struct clock_event_device timer_ce; +static char timer_ce_enabled = 0; + +#ifdef CONFIG_SMP +DEFINE_PER_CPU(struct clock_event_device, sparc32_clockevent); +#endif + DEFINE_SPINLOCK(rtc_lock); EXPORT_SYMBOL(rtc_lock); @@ -75,36 +89,167 @@ EXPORT_SYMBOL(profile_pc); __volatile__ unsigned int *master_l10_counter; -u32 (*do_arch_gettimeoffset)(void); - int update_persistent_clock(struct timespec now) { return set_rtc_mmss(now.tv_sec); } -/* - * timer_interrupt() needs to keep up the real-time clock, - * as well as call the "xtime_update()" routine every clocktick - */ +irqreturn_t notrace timer_interrupt(int dummy, void *dev_id) +{ + if (timer_cs_enabled) { + write_seqlock(&timer_cs_lock); + timer_cs_internal_counter++; + clear_clock_irq(); + write_sequnlock(&timer_cs_lock); + } else { + clear_clock_irq(); + } -#define TICK_SIZE (tick_nsec / 1000) + if (timer_ce_enabled) + timer_ce.event_handler(&timer_ce); -static irqreturn_t timer_interrupt(int dummy, void *dev_id) + return IRQ_HANDLED; +} + +static void timer_ce_set_mode(enum clock_event_mode mode, + struct clock_event_device *evt) { -#ifndef CONFIG_SMP - profile_tick(CPU_PROFILING); -#endif + switch (mode) { + case CLOCK_EVT_MODE_PERIODIC: + case CLOCK_EVT_MODE_RESUME: + timer_ce_enabled = 1; + break; + case CLOCK_EVT_MODE_SHUTDOWN: + timer_ce_enabled = 0; + break; + default: + break; + } + smp_mb(); +} + +static __init void setup_timer_ce(void) +{ + struct clock_event_device *ce = &timer_ce; + + BUG_ON(smp_processor_id() != boot_cpu_id); + + ce->name = "timer_ce"; + ce->rating = 100; + ce->features = CLOCK_EVT_FEAT_PERIODIC; + ce->set_mode = timer_ce_set_mode; + ce->cpumask = cpu_possible_mask; + ce->shift = 32; + ce->mult = div_sc(sparc_config.clock_rate, NSEC_PER_SEC, + ce->shift); + clockevents_register_device(ce); +} - clear_clock_irq(); +static unsigned int sbus_cycles_offset(void) +{ + unsigned int val, offset; - xtime_update(1); + val = *master_l10_counter; + offset = (val >> TIMER_VALUE_SHIFT) & TIMER_VALUE_MASK; -#ifndef CONFIG_SMP - update_process_times(user_mode(get_irq_regs())); -#endif - return IRQ_HANDLED; + /* Limit hit? */ + if (val & TIMER_LIMIT_BIT) + offset += sparc_config.cs_period; + + return offset; } +static cycle_t timer_cs_read(struct clocksource *cs) +{ + unsigned int seq, offset; + u64 cycles; + + do { + seq = read_seqbegin(&timer_cs_lock); + + cycles = timer_cs_internal_counter; + offset = sparc_config.get_cycles_offset(); + } while (read_seqretry(&timer_cs_lock, seq)); + + /* Count absolute cycles */ + cycles *= sparc_config.cs_period; + cycles += offset; + + return cycles; +} + +static struct clocksource timer_cs = { + .name = "timer_cs", + .rating = 100, + .read = timer_cs_read, + .mask = CLOCKSOURCE_MASK(64), + .shift = 2, + .flags = CLOCK_SOURCE_IS_CONTINUOUS, +}; + +static __init int setup_timer_cs(void) +{ + timer_cs_enabled = 1; + timer_cs.mult = clocksource_hz2mult(sparc_config.clock_rate, + timer_cs.shift); + + return clocksource_register(&timer_cs); +} + +#ifdef CONFIG_SMP +static void percpu_ce_setup(enum clock_event_mode mode, + struct clock_event_device *evt) +{ + int cpu = __first_cpu(evt->cpumask); + + switch (mode) { + case CLOCK_EVT_MODE_PERIODIC: + load_profile_irq(cpu, SBUS_CLOCK_RATE / HZ); + break; + case CLOCK_EVT_MODE_ONESHOT: + case CLOCK_EVT_MODE_SHUTDOWN: + case CLOCK_EVT_MODE_UNUSED: + load_profile_irq(cpu, 0); + break; + default: + break; + } +} + +static int percpu_ce_set_next_event(unsigned long delta, + struct clock_event_device *evt) +{ + int cpu = __first_cpu(evt->cpumask); + unsigned int next = (unsigned int)delta; + + load_profile_irq(cpu, next); + return 0; +} + +void register_percpu_ce(int cpu) +{ + struct clock_event_device *ce = &per_cpu(sparc32_clockevent, cpu); + unsigned int features = CLOCK_EVT_FEAT_PERIODIC; + + if (sparc_config.features & FEAT_L14_ONESHOT) + features |= CLOCK_EVT_FEAT_ONESHOT; + + ce->name = "percpu_ce"; + ce->rating = 200; + ce->features = features; + ce->set_mode = percpu_ce_setup; + ce->set_next_event = percpu_ce_set_next_event; + ce->cpumask = cpumask_of(cpu); + ce->shift = 32; + ce->mult = div_sc(sparc_config.clock_rate, NSEC_PER_SEC, + ce->shift); + ce->max_delta_ns = clockevent_delta2ns(sparc_config.clock_rate, ce); + ce->min_delta_ns = clockevent_delta2ns(100, ce); + + clockevents_register_device(ce); +} +#endif + static unsigned char mostek_read_byte(struct device *dev, u32 ofs) { struct platform_device *pdev = to_platform_device(dev); @@ -195,38 +340,30 @@ static int __init clock_init(void) */ fs_initcall(clock_init); - -u32 sbus_do_gettimeoffset(void) +static void __init sparc32_late_time_init(void) { - unsigned long val = *master_l10_counter; - unsigned long usec = (val >> 10) & 0x1fffff; - - /* Limit hit? */ - if (val & 0x80000000) - usec += 1000000 / HZ; - - return usec * 1000; + if (sparc_config.features & FEAT_L10_CLOCKEVENT) + setup_timer_ce(); + if (sparc_config.features & FEAT_L10_CLOCKSOURCE) + setup_timer_cs(); +#ifdef CONFIG_SMP + register_percpu_ce(smp_processor_id()); +#endif } - -u32 arch_gettimeoffset(void) +static void __init sbus_time_init(void) { - if (unlikely(!do_arch_gettimeoffset)) - return 0; - return do_arch_gettimeoffset(); + sparc_config.get_cycles_offset = sbus_cycles_offset; + sparc_config.init_timers(); } -static void __init sbus_time_init(void) +void __init time_init(void) { - do_arch_gettimeoffset = sbus_do_gettimeoffset; - btfixup(); - sparc_config.init_timers(timer_interrupt); -} + sparc_config.features = 0; + late_time_init = sparc32_late_time_init; -void __init time_init(void) -{ if (pcic_present()) pci_time_init(); else |