diff options
Diffstat (limited to 'arch/arm/mach-ns9xxx/time.c')
| -rw-r--r-- | arch/arm/mach-ns9xxx/time.c | 172 |
1 files changed, 134 insertions, 38 deletions
diff --git a/arch/arm/mach-ns9xxx/time.c b/arch/arm/mach-ns9xxx/time.c index b97d0c54a388..c3dd1f4acb99 100644 --- a/arch/arm/mach-ns9xxx/time.c +++ b/arch/arm/mach-ns9xxx/time.c @@ -11,78 +11,174 @@ #include <linux/jiffies.h> #include <linux/interrupt.h> #include <linux/irq.h> +#include <linux/stringify.h> +#include <linux/clocksource.h> +#include <linux/clockchips.h> + #include <asm/arch-ns9xxx/regs-sys.h> #include <asm/arch-ns9xxx/clock.h> #include <asm/arch-ns9xxx/irqs.h> #include <asm/arch/system.h> #include "generic.h" -#define TIMERCLOCKSELECT 64 +#define TIMER_CLOCKSOURCE 0 +#define TIMER_CLOCKEVENT 1 +static u32 latch; + +static cycle_t ns9xxx_clocksource_read(void) +{ + return __raw_readl(SYS_TR(TIMER_CLOCKSOURCE)); +} -static u32 usecs_per_tick; +static struct clocksource ns9xxx_clocksource = { + .name = "ns9xxx-timer" __stringify(TIMER_CLOCKSOURCE), + .rating = 300, + .read = ns9xxx_clocksource_read, + .mask = CLOCKSOURCE_MASK(32), + .shift = 20, + .flags = CLOCK_SOURCE_IS_CONTINUOUS, +}; -static irqreturn_t -ns9xxx_timer_interrupt(int irq, void *dev_id) +static void ns9xxx_clockevent_setmode(enum clock_event_mode mode, + struct clock_event_device *clk) { - write_seqlock(&xtime_lock); - timer_tick(); - write_sequnlock(&xtime_lock); + u32 tc = __raw_readl(SYS_TC(TIMER_CLOCKEVENT)); + + switch(mode) { + case CLOCK_EVT_MODE_PERIODIC: + __raw_writel(latch, SYS_TRC(TIMER_CLOCKEVENT)); + REGSET(tc, SYS_TCx, REN, EN); + REGSET(tc, SYS_TCx, INTS, EN); + REGSET(tc, SYS_TCx, TEN, EN); + break; + + case CLOCK_EVT_MODE_ONESHOT: + REGSET(tc, SYS_TCx, REN, DIS); + REGSET(tc, SYS_TCx, INTS, EN); + + /* fall through */ + + case CLOCK_EVT_MODE_UNUSED: + case CLOCK_EVT_MODE_SHUTDOWN: + case CLOCK_EVT_MODE_RESUME: + default: + REGSET(tc, SYS_TCx, TEN, DIS); + break; + } + + __raw_writel(tc, SYS_TC(TIMER_CLOCKEVENT)); +} - return IRQ_HANDLED; +static int ns9xxx_clockevent_setnextevent(unsigned long evt, + struct clock_event_device *clk) +{ + u32 tc = __raw_readl(SYS_TC(TIMER_CLOCKEVENT)); + + if (REGGET(tc, SYS_TCx, TEN)) { + REGSET(tc, SYS_TCx, TEN, DIS); + __raw_writel(tc, SYS_TC(TIMER_CLOCKEVENT)); + } + + REGSET(tc, SYS_TCx, TEN, EN); + + __raw_writel(evt, SYS_TRC(TIMER_CLOCKEVENT)); + + __raw_writel(tc, SYS_TC(TIMER_CLOCKEVENT)); + + return 0; } -static unsigned long ns9xxx_timer_gettimeoffset(void) +static struct clock_event_device ns9xxx_clockevent_device = { + .name = "ns9xxx-timer" __stringify(TIMER_CLOCKEVENT), + .shift = 20, + .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, + .set_mode = ns9xxx_clockevent_setmode, + .set_next_event = ns9xxx_clockevent_setnextevent, +}; + +static irqreturn_t ns9xxx_clockevent_handler(int irq, void *dev_id) { - /* return the microseconds which have passed since the last interrupt - * was _serviced_. That is, if an interrupt is pending or the counter - * reloads, return one period more. */ + int timerno = irq - IRQ_TIMER0; + u32 tc; - u32 counter1 = SYS_TR(0); - int pending = SYS_ISR & (1 << IRQ_TIMER0); - u32 counter2 = SYS_TR(0); - u32 elapsed; + struct clock_event_device *evt = &ns9xxx_clockevent_device; - if (pending || counter2 > counter1) - elapsed = 2 * SYS_TRC(0) - counter2; - else - elapsed = SYS_TRC(0) - counter1; + /* clear irq */ + tc = __raw_readl(SYS_TC(timerno)); + if (REGGET(tc, SYS_TCx, REN) == SYS_TCx_REN_DIS) { + REGSET(tc, SYS_TCx, TEN, DIS); + __raw_writel(tc, SYS_TC(timerno)); + } + REGSET(tc, SYS_TCx, INTC, SET); + __raw_writel(tc, SYS_TC(timerno)); + REGSET(tc, SYS_TCx, INTC, UNSET); + __raw_writel(tc, SYS_TC(timerno)); - return (elapsed * usecs_per_tick) >> 16; + evt->event_handler(evt); + return IRQ_HANDLED; } -static struct irqaction ns9xxx_timer_irq = { - .name = "NS9xxx Timer Tick", - .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL, - .handler = ns9xxx_timer_interrupt, +static struct irqaction ns9xxx_clockevent_action = { + .name = "ns9xxx-timer" __stringify(TIMER_CLOCKEVENT), + .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL, + .handler = ns9xxx_clockevent_handler, }; static void __init ns9xxx_timer_init(void) { int tc; - usecs_per_tick = - SH_DIV(1000000 * TIMERCLOCKSELECT, ns9xxx_cpuclock(), 16); + tc = __raw_readl(SYS_TC(TIMER_CLOCKSOURCE)); + if (REGGET(tc, SYS_TCx, TEN)) { + REGSET(tc, SYS_TCx, TEN, DIS); + __raw_writel(tc, SYS_TC(TIMER_CLOCKSOURCE)); + } - /* disable timer */ - if ((tc = SYS_TC(0)) & SYS_TCx_TEN) - SYS_TC(0) = tc & ~SYS_TCx_TEN; - - SYS_TRC(0) = SH_DIV(ns9xxx_cpuclock(), (TIMERCLOCKSELECT * HZ), 0); + __raw_writel(0, SYS_TRC(TIMER_CLOCKSOURCE)); REGSET(tc, SYS_TCx, TEN, EN); - REGSET(tc, SYS_TCx, TLCS, DIV64); /* This must match TIMERCLOCKSELECT */ - REGSET(tc, SYS_TCx, INTS, EN); - REGSET(tc, SYS_TCx, UDS, DOWN); REGSET(tc, SYS_TCx, TDBG, STOP); + REGSET(tc, SYS_TCx, TLCS, CPU); + REGSET(tc, SYS_TCx, TM, IEE); + REGSET(tc, SYS_TCx, INTS, DIS); + REGSET(tc, SYS_TCx, UDS, UP); REGSET(tc, SYS_TCx, TSZ, 32); REGSET(tc, SYS_TCx, REN, EN); - SYS_TC(0) = tc; - setup_irq(IRQ_TIMER0, &ns9xxx_timer_irq); + __raw_writel(tc, SYS_TC(TIMER_CLOCKSOURCE)); + + ns9xxx_clocksource.mult = clocksource_hz2mult(ns9xxx_cpuclock(), + ns9xxx_clocksource.shift); + + clocksource_register(&ns9xxx_clocksource); + + latch = SH_DIV(ns9xxx_cpuclock(), HZ, 0); + + tc = __raw_readl(SYS_TC(TIMER_CLOCKEVENT)); + REGSET(tc, SYS_TCx, TEN, DIS); + REGSET(tc, SYS_TCx, TDBG, STOP); + REGSET(tc, SYS_TCx, TLCS, CPU); + REGSET(tc, SYS_TCx, TM, IEE); + REGSET(tc, SYS_TCx, INTS, DIS); + REGSET(tc, SYS_TCx, UDS, DOWN); + REGSET(tc, SYS_TCx, TSZ, 32); + REGSET(tc, SYS_TCx, REN, EN); + __raw_writel(tc, SYS_TC(TIMER_CLOCKEVENT)); + + ns9xxx_clockevent_device.mult = div_sc(ns9xxx_cpuclock(), + NSEC_PER_SEC, ns9xxx_clockevent_device.shift); + ns9xxx_clockevent_device.max_delta_ns = + clockevent_delta2ns(-1, &ns9xxx_clockevent_device); + ns9xxx_clockevent_device.min_delta_ns = + clockevent_delta2ns(1, &ns9xxx_clockevent_device); + + ns9xxx_clockevent_device.cpumask = cpumask_of_cpu(0); + clockevents_register_device(&ns9xxx_clockevent_device); + + setup_irq(IRQ_TIMER0 + TIMER_CLOCKEVENT, &ns9xxx_clockevent_action); } struct sys_timer ns9xxx_timer = { .init = ns9xxx_timer_init, - .offset = ns9xxx_timer_gettimeoffset, }; |