From 1fa9be72b558c39459f98835eb86dbb4ef4da30b Mon Sep 17 00:00:00 2001 From: Graf Yang Date: Fri, 15 May 2009 11:01:59 +0000 Subject: Blackfin: add support for gptimer0 as a tick source For systems where the core cycles are not a usable tick source (like SMP or cycles gets updated), enable gptimer0 as an alternative. Signed-off-by: Graf Yang Signed-off-by: Mike Frysinger --- arch/blackfin/kernel/time-ts.c | 222 +++++++++++++++++++++++++++++++++-------- arch/blackfin/kernel/time.c | 10 +- 2 files changed, 188 insertions(+), 44 deletions(-) (limited to 'arch/blackfin/kernel') diff --git a/arch/blackfin/kernel/time-ts.c b/arch/blackfin/kernel/time-ts.c index 27646121280..0791eba40d9 100644 --- a/arch/blackfin/kernel/time-ts.c +++ b/arch/blackfin/kernel/time-ts.c @@ -20,8 +20,9 @@ #include #include +#include -#ifdef CONFIG_CYCLES_CLOCKSOURCE +#if defined(CONFIG_CYCLES_CLOCKSOURCE) /* Accelerators for sched_clock() * convert from cycles(64bits) => nanoseconds (64bits) @@ -58,15 +59,15 @@ static inline unsigned long long cycles_2_ns(cycle_t cyc) return (cyc * cyc2ns_scale) >> CYC2NS_SCALE_FACTOR; } -static cycle_t read_cycles(struct clocksource *cs) +static cycle_t bfin_read_cycles(struct clocksource *cs) { return __bfin_cycles_off + (get_cycles() << __bfin_cycles_mod); } -static struct clocksource clocksource_bfin = { - .name = "bfin_cycles", +static struct clocksource bfin_cs_cycles = { + .name = "bfin_cs_cycles", .rating = 350, - .read = read_cycles, + .read = bfin_read_cycles, .mask = CLOCKSOURCE_MASK(64), .shift = 22, .flags = CLOCK_SOURCE_IS_CONTINUOUS, @@ -74,53 +75,198 @@ static struct clocksource clocksource_bfin = { unsigned long long sched_clock(void) { - return cycles_2_ns(read_cycles(&clocksource_bfin)); + return cycles_2_ns(bfin_read_cycles(&bfin_cs_cycles)); } -static int __init bfin_clocksource_init(void) +static int __init bfin_cs_cycles_init(void) { set_cyc2ns_scale(get_cclk() / 1000); - clocksource_bfin.mult = clocksource_hz2mult(get_cclk(), clocksource_bfin.shift); + bfin_cs_cycles.mult = \ + clocksource_hz2mult(get_cclk(), bfin_cs_cycles.shift); - if (clocksource_register(&clocksource_bfin)) + if (clocksource_register(&bfin_cs_cycles)) panic("failed to register clocksource"); return 0; } +#else +# define bfin_cs_cycles_init() +#endif + +#ifdef CONFIG_GPTMR0_CLOCKSOURCE + +void __init setup_gptimer0(void) +{ + disable_gptimers(TIMER0bit); + + set_gptimer_config(TIMER0_id, \ + TIMER_OUT_DIS | TIMER_PERIOD_CNT | TIMER_MODE_PWM); + set_gptimer_period(TIMER0_id, -1); + set_gptimer_pwidth(TIMER0_id, -2); + SSYNC(); + enable_gptimers(TIMER0bit); +} + +static cycle_t bfin_read_gptimer0(void) +{ + return bfin_read_TIMER0_COUNTER(); +} + +static struct clocksource bfin_cs_gptimer0 = { + .name = "bfin_cs_gptimer0", + .rating = 400, + .read = bfin_read_gptimer0, + .mask = CLOCKSOURCE_MASK(32), + .shift = 22, + .flags = CLOCK_SOURCE_IS_CONTINUOUS, +}; + +static int __init bfin_cs_gptimer0_init(void) +{ + setup_gptimer0(); + bfin_cs_gptimer0.mult = \ + clocksource_hz2mult(get_sclk(), bfin_cs_gptimer0.shift); + + if (clocksource_register(&bfin_cs_gptimer0)) + panic("failed to register clocksource"); + + return 0; +} #else -# define bfin_clocksource_init() +# define bfin_cs_gptimer0_init() #endif +#ifdef CONFIG_CORE_TIMER_IRQ_L1 +__attribute__((l1_text)) +#endif +irqreturn_t timer_interrupt(int irq, void *dev_id); + +static int bfin_timer_set_next_event(unsigned long, \ + struct clock_event_device *); + +static void bfin_timer_set_mode(enum clock_event_mode, \ + struct clock_event_device *); + +static struct clock_event_device clockevent_bfin = { +#if defined(CONFIG_TICKSOURCE_GPTMR0) + .name = "bfin_gptimer0", + .rating = 300, + .irq = IRQ_TIMER0, +#else + .name = "bfin_core_timer", + .rating = 350, + .irq = IRQ_CORETMR, +#endif + .shift = 32, + .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, + .set_next_event = bfin_timer_set_next_event, + .set_mode = bfin_timer_set_mode, +}; + +static struct irqaction bfin_timer_irq = { +#if defined(CONFIG_TICKSOURCE_GPTMR0) + .name = "Blackfin GPTimer0", +#else + .name = "Blackfin CoreTimer", +#endif + .flags = IRQF_DISABLED | IRQF_TIMER | \ + IRQF_IRQPOLL | IRQF_PERCPU, + .handler = timer_interrupt, + .dev_id = &clockevent_bfin, +}; + +#if defined(CONFIG_TICKSOURCE_GPTMR0) static int bfin_timer_set_next_event(unsigned long cycles, struct clock_event_device *evt) { + disable_gptimers(TIMER0bit); + + /* it starts counting three SCLK cycles after the TIMENx bit is set */ + set_gptimer_pwidth(TIMER0_id, cycles - 3); + enable_gptimers(TIMER0bit); + return 0; +} + +static void bfin_timer_set_mode(enum clock_event_mode mode, + struct clock_event_device *evt) +{ + switch (mode) { + case CLOCK_EVT_MODE_PERIODIC: { + set_gptimer_config(TIMER0_id, \ + TIMER_OUT_DIS | TIMER_IRQ_ENA | \ + TIMER_PERIOD_CNT | TIMER_MODE_PWM); + set_gptimer_period(TIMER0_id, get_sclk() / HZ); + set_gptimer_pwidth(TIMER0_id, get_sclk() / HZ - 1); + enable_gptimers(TIMER0bit); + break; + } + case CLOCK_EVT_MODE_ONESHOT: + disable_gptimers(TIMER0bit); + set_gptimer_config(TIMER0_id, \ + TIMER_OUT_DIS | TIMER_IRQ_ENA | TIMER_MODE_PWM); + set_gptimer_period(TIMER0_id, 0); + break; + case CLOCK_EVT_MODE_UNUSED: + case CLOCK_EVT_MODE_SHUTDOWN: + disable_gptimers(TIMER0bit); + break; + case CLOCK_EVT_MODE_RESUME: + break; + } +} + +static void bfin_timer_ack(void) +{ + set_gptimer_status(TIMER_GROUP1, TIMER_STATUS_TIMIL0); +} + +static void __init bfin_timer_init(void) +{ + disable_gptimers(TIMER0bit); +} + +static unsigned long __init bfin_clockevent_check(void) +{ + setup_irq(IRQ_TIMER0, &bfin_timer_irq); + return get_sclk(); +} + +#else /* CONFIG_TICKSOURCE_CORETMR */ + +static int bfin_timer_set_next_event(unsigned long cycles, + struct clock_event_device *evt) +{ + bfin_write_TCNTL(TMPWR); + CSYNC(); bfin_write_TCOUNT(cycles); CSYNC(); + bfin_write_TCNTL(TMPWR | TMREN); return 0; } static void bfin_timer_set_mode(enum clock_event_mode mode, - struct clock_event_device *evt) + struct clock_event_device *evt) { switch (mode) { case CLOCK_EVT_MODE_PERIODIC: { unsigned long tcount = ((get_cclk() / (HZ * TIME_SCALE)) - 1); bfin_write_TCNTL(TMPWR); - bfin_write_TSCALE(TIME_SCALE - 1); CSYNC(); + bfin_write_TSCALE(TIME_SCALE - 1); bfin_write_TPERIOD(tcount); bfin_write_TCOUNT(tcount); - bfin_write_TCNTL(TMPWR | TMREN | TAUTORLD); CSYNC(); + bfin_write_TCNTL(TMPWR | TMREN | TAUTORLD); break; } case CLOCK_EVT_MODE_ONESHOT: + bfin_write_TCNTL(TMPWR); + CSYNC(); bfin_write_TSCALE(TIME_SCALE - 1); + bfin_write_TPERIOD(0); bfin_write_TCOUNT(0); - bfin_write_TCNTL(TMPWR | TMREN); - CSYNC(); break; case CLOCK_EVT_MODE_UNUSED: case CLOCK_EVT_MODE_SHUTDOWN: @@ -132,6 +278,10 @@ static void bfin_timer_set_mode(enum clock_event_mode mode, } } +static void bfin_timer_ack(void) +{ +} + static void __init bfin_timer_init(void) { /* power up the timer, but don't enable it just yet */ @@ -145,38 +295,32 @@ static void __init bfin_timer_init(void) bfin_write_TPERIOD(0); bfin_write_TCOUNT(0); - /* now enable the timer */ CSYNC(); } +static unsigned long __init bfin_clockevent_check(void) +{ + setup_irq(IRQ_CORETMR, &bfin_timer_irq); + return get_cclk() / TIME_SCALE; +} + +void __init setup_core_timer(void) +{ + bfin_timer_init(); + bfin_timer_set_mode(CLOCK_EVT_MODE_PERIODIC, NULL); +} +#endif /* CONFIG_TICKSOURCE_GPTMR0 */ + /* * timer_interrupt() needs to keep up the real-time clock, * as well as call the "do_timer()" routine every clocktick */ -#ifdef CONFIG_CORE_TIMER_IRQ_L1 -__attribute__((l1_text)) -#endif -irqreturn_t timer_interrupt(int irq, void *dev_id); - -static struct clock_event_device clockevent_bfin = { - .name = "bfin_core_timer", - .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, - .shift = 32, - .set_next_event = bfin_timer_set_next_event, - .set_mode = bfin_timer_set_mode, -}; - -static struct irqaction bfin_timer_irq = { - .name = "Blackfin Core Timer", - .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL, - .handler = timer_interrupt, - .dev_id = &clockevent_bfin, -}; - irqreturn_t timer_interrupt(int irq, void *dev_id) { struct clock_event_device *evt = dev_id; + smp_mb(); evt->event_handler(evt); + bfin_timer_ack(); return IRQ_HANDLED; } @@ -184,9 +328,8 @@ static int __init bfin_clockevent_init(void) { unsigned long timer_clk; - timer_clk = get_cclk() / TIME_SCALE; + timer_clk = bfin_clockevent_check(); - setup_irq(IRQ_CORETMR, &bfin_timer_irq); bfin_timer_init(); clockevent_bfin.mult = div_sc(timer_clk, NSEC_PER_SEC, clockevent_bfin.shift); @@ -218,6 +361,7 @@ void __init time_init(void) xtime.tv_nsec = 0; set_normalized_timespec(&wall_to_monotonic, -xtime.tv_sec, -xtime.tv_nsec); - bfin_clocksource_init(); + bfin_cs_cycles_init(); + bfin_cs_gptimer0_init(); bfin_clockevent_init(); } diff --git a/arch/blackfin/kernel/time.c b/arch/blackfin/kernel/time.c index 1bbacfbd4c5..daa02d45f03 100644 --- a/arch/blackfin/kernel/time.c +++ b/arch/blackfin/kernel/time.c @@ -31,7 +31,7 @@ static struct irqaction bfin_timer_irq = { #endif }; -#if defined(CONFIG_TICK_SOURCE_SYSTMR0) || defined(CONFIG_IPIPE) +#if defined(CONFIG_TICKSOURCE_GPTMR0) || defined(CONFIG_IPIPE) void __init setup_system_timer0(void) { /* Power down the core timer, just to play safe. */ @@ -74,7 +74,7 @@ void __init setup_core_timer(void) static void __init time_sched_init(irqreturn_t(*timer_routine) (int, void *)) { -#if defined(CONFIG_TICK_SOURCE_SYSTMR0) || defined(CONFIG_IPIPE) +#if defined(CONFIG_TICKSOURCE_GPTMR0) || defined(CONFIG_IPIPE) setup_system_timer0(); bfin_timer_irq.handler = timer_routine; setup_irq(IRQ_TIMER0, &bfin_timer_irq); @@ -94,7 +94,7 @@ static unsigned long gettimeoffset(void) unsigned long offset; unsigned long clocks_per_jiffy; -#if defined(CONFIG_TICK_SOURCE_SYSTMR0) || defined(CONFIG_IPIPE) +#if defined(CONFIG_TICKSOURCE_GPTMR0) || defined(CONFIG_IPIPE) clocks_per_jiffy = bfin_read_TIMER0_PERIOD(); offset = bfin_read_TIMER0_COUNTER() / \ (((clocks_per_jiffy + 1) * HZ) / USEC_PER_SEC); @@ -133,7 +133,7 @@ irqreturn_t timer_interrupt(int irq, void *dummy) static long last_rtc_update; write_seqlock(&xtime_lock); -#if defined(CONFIG_TICK_SOURCE_SYSTMR0) && !defined(CONFIG_IPIPE) +#if defined(CONFIG_TICKSOURCE_GPTMR0) && !defined(CONFIG_IPIPE) /* * TIMIL0 is latched in __ipipe_grab_irq() when the I-Pipe is * enabled. @@ -159,7 +159,7 @@ irqreturn_t timer_interrupt(int irq, void *dummy) /* Do it again in 60s. */ last_rtc_update = xtime.tv_sec - 600; } -#if defined(CONFIG_TICK_SOURCE_SYSTMR0) && !defined(CONFIG_IPIPE) +#if defined(CONFIG_TICKSOURCE_GPTMR0) && !defined(CONFIG_IPIPE) set_gptimer_status(0, TIMER_STATUS_TIMIL0); } #endif -- cgit v1.2.3