diff --git a/arch/arm/mach-davinci/include/mach/common.h b/arch/arm/mach-davinci/include/mach/common.h index 22db67744875..715528f0dbdb 100644 --- a/arch/arm/mach-davinci/include/mach/common.h +++ b/arch/arm/mach-davinci/include/mach/common.h @@ -30,6 +30,8 @@ struct davinci_timer_instance { void __iomem *base; u32 bottom_irq; u32 top_irq; + unsigned long cmp_off; + unsigned int cmp_irq; }; struct davinci_timer_info { diff --git a/arch/arm/mach-davinci/time.c b/arch/arm/mach-davinci/time.c index f80ae25a52e4..fc90d3ee0eba 100644 --- a/arch/arm/mach-davinci/time.c +++ b/arch/arm/mach-davinci/time.c @@ -46,14 +46,24 @@ enum { }; /* Timer register offsets */ -#define PID12 0x0 -#define TIM12 0x10 -#define TIM34 0x14 -#define PRD12 0x18 -#define PRD34 0x1c -#define TCR 0x20 -#define TGCR 0x24 -#define WDTCR 0x28 +#define PID12 0x0 +#define TIM12 0x10 +#define TIM34 0x14 +#define PRD12 0x18 +#define PRD34 0x1c +#define TCR 0x20 +#define TGCR 0x24 +#define WDTCR 0x28 + +/* Offsets of the 8 compare registers */ +#define CMP12_0 0x60 +#define CMP12_1 0x64 +#define CMP12_2 0x68 +#define CMP12_3 0x6c +#define CMP12_4 0x70 +#define CMP12_5 0x74 +#define CMP12_6 0x78 +#define CMP12_7 0x7c /* Timer register bitfields */ #define TCR_ENAMODE_DISABLE 0x0 @@ -85,6 +95,7 @@ struct timer_s { unsigned int id; unsigned long period; unsigned long opts; + unsigned long flags; void __iomem *base; unsigned long tim_off; unsigned long prd_off; @@ -94,9 +105,13 @@ struct timer_s { static struct timer_s timers[]; /* values for 'opts' field of struct timer_s */ -#define TIMER_OPTS_DISABLED 0x00 -#define TIMER_OPTS_ONESHOT 0x01 -#define TIMER_OPTS_PERIODIC 0x02 +#define TIMER_OPTS_DISABLED 0x01 +#define TIMER_OPTS_ONESHOT 0x02 +#define TIMER_OPTS_PERIODIC 0x04 +#define TIMER_OPTS_STATE_MASK 0x07 + +#define TIMER_OPTS_USE_COMPARE 0x80000000 +#define USING_COMPARE(t) ((t)->opts & TIMER_OPTS_USE_COMPARE) static char *id_to_name[] = { [T0_BOT] = "timer0_0", @@ -107,24 +122,41 @@ static char *id_to_name[] = { static int timer32_config(struct timer_s *t) { - u32 tcr = __raw_readl(t->base + TCR); + u32 tcr; + struct davinci_soc_info *soc_info = davinci_get_soc_info(); - /* disable timer */ - tcr &= ~(TCR_ENAMODE_MASK << t->enamode_shift); - __raw_writel(tcr, t->base + TCR); + if (USING_COMPARE(t)) { + struct davinci_timer_instance *dtip = + soc_info->timer_info->timers; + int event_timer = ID_TO_TIMER(timers[TID_CLOCKEVENT].id); - /* reset counter to zero, set new period */ - __raw_writel(0, t->base + t->tim_off); - __raw_writel(t->period, t->base + t->prd_off); + /* + * Next interrupt should be the current time reg value plus + * the new period (using 32-bit unsigned addition/wrapping + * to 0 on overflow). This assumes that the clocksource + * is setup to count to 2^32-1 before wrapping around to 0. + */ + __raw_writel(__raw_readl(t->base + t->tim_off) + t->period, + t->base + dtip[event_timer].cmp_off); + } else { + tcr = __raw_readl(t->base + TCR); - /* Set enable mode */ - if (t->opts & TIMER_OPTS_ONESHOT) { - tcr |= TCR_ENAMODE_ONESHOT << t->enamode_shift; - } else if (t->opts & TIMER_OPTS_PERIODIC) { - tcr |= TCR_ENAMODE_PERIODIC << t->enamode_shift; + /* disable timer */ + tcr &= ~(TCR_ENAMODE_MASK << t->enamode_shift); + __raw_writel(tcr, t->base + TCR); + + /* reset counter to zero, set new period */ + __raw_writel(0, t->base + t->tim_off); + __raw_writel(t->period, t->base + t->prd_off); + + /* Set enable mode */ + if (t->opts & TIMER_OPTS_ONESHOT) + tcr |= TCR_ENAMODE_ONESHOT << t->enamode_shift; + else if (t->opts & TIMER_OPTS_PERIODIC) + tcr |= TCR_ENAMODE_PERIODIC << t->enamode_shift; + + __raw_writel(tcr, t->base + TCR); } - - __raw_writel(tcr, t->base + TCR); return 0; } @@ -222,8 +254,11 @@ static void __init timer_init(void) /* Register interrupt */ t->irqaction.name = t->name; t->irqaction.dev_id = (void *)t; - if (t->irqaction.handler != NULL) + + if (t->irqaction.handler != NULL) { + irq = USING_COMPARE(t) ? dtip[i].cmp_irq : irq; setup_irq(irq, &t->irqaction); + } timer32_config(&timers[i]); } @@ -268,15 +303,18 @@ static void davinci_set_mode(enum clock_event_mode mode, switch (mode) { case CLOCK_EVT_MODE_PERIODIC: t->period = davinci_clock_tick_rate / (HZ); - t->opts = TIMER_OPTS_PERIODIC; + t->opts &= ~TIMER_OPTS_STATE_MASK; + t->opts |= TIMER_OPTS_PERIODIC; timer32_config(t); break; case CLOCK_EVT_MODE_ONESHOT: - t->opts = TIMER_OPTS_ONESHOT; + t->opts &= ~TIMER_OPTS_STATE_MASK; + t->opts |= TIMER_OPTS_ONESHOT; break; case CLOCK_EVT_MODE_UNUSED: case CLOCK_EVT_MODE_SHUTDOWN: - t->opts = TIMER_OPTS_DISABLED; + t->opts &= ~TIMER_OPTS_STATE_MASK; + t->opts |= TIMER_OPTS_DISABLED; break; case CLOCK_EVT_MODE_RESUME: break; @@ -295,12 +333,40 @@ static void __init davinci_timer_init(void) { struct clk *timer_clk; struct davinci_soc_info *soc_info = &davinci_soc_info; - + unsigned int clockevent_id; + unsigned int clocksource_id; static char err[] __initdata = KERN_ERR "%s: can't register clocksource!\n"; - timers[TID_CLOCKEVENT].id = soc_info->timer_info->clockevent_id; - timers[TID_CLOCKSOURCE].id = soc_info->timer_info->clocksource_id; + clockevent_id = soc_info->timer_info->clockevent_id; + clocksource_id = soc_info->timer_info->clocksource_id; + + timers[TID_CLOCKEVENT].id = clockevent_id; + timers[TID_CLOCKSOURCE].id = clocksource_id; + + /* + * If using same timer for both clock events & clocksource, + * a compare register must be used to generate an event interrupt. + * This is equivalent to a oneshot timer only (not periodic). + */ + if (clockevent_id == clocksource_id) { + struct davinci_timer_instance *dtip = + soc_info->timer_info->timers; + int event_timer = ID_TO_TIMER(clockevent_id); + + /* Only bottom timers can use compare regs */ + if (IS_TIMER_TOP(clockevent_id)) + pr_warning("davinci_timer_init: Invalid use" + " of system timers. Results unpredictable.\n"); + else if ((dtip[event_timer].cmp_off == 0) + || (dtip[event_timer].cmp_irq == 0)) + pr_warning("davinci_timer_init: Invalid timer instance" + " setup. Results unpredictable.\n"); + else { + timers[TID_CLOCKEVENT].opts |= TIMER_OPTS_USE_COMPARE; + clockevent_davinci.features = CLOCK_EVT_FEAT_ONESHOT; + } + } /* init timer hw */ timer_init(); @@ -312,7 +378,7 @@ static void __init davinci_timer_init(void) davinci_clock_tick_rate = clk_get_rate(timer_clk); /* setup clocksource */ - clocksource_davinci.name = id_to_name[timers[TID_CLOCKSOURCE].id]; + clocksource_davinci.name = id_to_name[clocksource_id]; clocksource_davinci.mult = clocksource_khz2mult(davinci_clock_tick_rate/1000, clocksource_davinci.shift); @@ -325,8 +391,7 @@ static void __init davinci_timer_init(void) clockevent_davinci.shift); clockevent_davinci.max_delta_ns = clockevent_delta2ns(0xfffffffe, &clockevent_davinci); - clockevent_davinci.min_delta_ns = - clockevent_delta2ns(1, &clockevent_davinci); + clockevent_davinci.min_delta_ns = 50000; /* 50 usec */ clockevent_davinci.cpumask = cpumask_of(0); clockevents_register_device(&clockevent_davinci);