diff options
Diffstat (limited to 'arch/arm/mach-footbridge/dc21285-timer.c')
-rw-r--r-- | arch/arm/mach-footbridge/dc21285-timer.c | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/arch/arm/mach-footbridge/dc21285-timer.c b/arch/arm/mach-footbridge/dc21285-timer.c new file mode 100644 index 000000000..bf7aa7d29 --- /dev/null +++ b/arch/arm/mach-footbridge/dc21285-timer.c @@ -0,0 +1,142 @@ +/* + * linux/arch/arm/mach-footbridge/dc21285-timer.c + * + * Copyright (C) 1998 Russell King. + * Copyright (C) 1998 Phil Blundell + */ +#include <linux/clockchips.h> +#include <linux/clocksource.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/sched_clock.h> + +#include <asm/irq.h> + +#include <asm/hardware/dec21285.h> +#include <asm/mach/time.h> +#include <asm/system_info.h> + +#include "common.h" + +static cycle_t cksrc_dc21285_read(struct clocksource *cs) +{ + return cs->mask - *CSR_TIMER2_VALUE; +} + +static int cksrc_dc21285_enable(struct clocksource *cs) +{ + *CSR_TIMER2_LOAD = cs->mask; + *CSR_TIMER2_CLR = 0; + *CSR_TIMER2_CNTL = TIMER_CNTL_ENABLE | TIMER_CNTL_DIV16; + return 0; +} + +static void cksrc_dc21285_disable(struct clocksource *cs) +{ + *CSR_TIMER2_CNTL = 0; +} + +static struct clocksource cksrc_dc21285 = { + .name = "dc21285_timer2", + .rating = 200, + .read = cksrc_dc21285_read, + .enable = cksrc_dc21285_enable, + .disable = cksrc_dc21285_disable, + .mask = CLOCKSOURCE_MASK(24), + .flags = CLOCK_SOURCE_IS_CONTINUOUS, +}; + +static int ckevt_dc21285_set_next_event(unsigned long delta, + struct clock_event_device *c) +{ + *CSR_TIMER1_CLR = 0; + *CSR_TIMER1_LOAD = delta; + *CSR_TIMER1_CNTL = TIMER_CNTL_ENABLE | TIMER_CNTL_DIV16; + + return 0; +} + +static void ckevt_dc21285_set_mode(enum clock_event_mode mode, + struct clock_event_device *c) +{ + switch (mode) { + case CLOCK_EVT_MODE_RESUME: + case CLOCK_EVT_MODE_PERIODIC: + *CSR_TIMER1_CLR = 0; + *CSR_TIMER1_LOAD = (mem_fclk_21285 + 8 * HZ) / (16 * HZ); + *CSR_TIMER1_CNTL = TIMER_CNTL_ENABLE | TIMER_CNTL_AUTORELOAD | + TIMER_CNTL_DIV16; + break; + + case CLOCK_EVT_MODE_ONESHOT: + case CLOCK_EVT_MODE_UNUSED: + case CLOCK_EVT_MODE_SHUTDOWN: + *CSR_TIMER1_CNTL = 0; + break; + } +} + +static struct clock_event_device ckevt_dc21285 = { + .name = "dc21285_timer1", + .features = CLOCK_EVT_FEAT_PERIODIC | + CLOCK_EVT_FEAT_ONESHOT, + .rating = 200, + .irq = IRQ_TIMER1, + .set_next_event = ckevt_dc21285_set_next_event, + .set_mode = ckevt_dc21285_set_mode, +}; + +static irqreturn_t timer1_interrupt(int irq, void *dev_id) +{ + struct clock_event_device *ce = dev_id; + + *CSR_TIMER1_CLR = 0; + + /* Stop the timer if in one-shot mode */ + if (ce->mode == CLOCK_EVT_MODE_ONESHOT) + *CSR_TIMER1_CNTL = 0; + + ce->event_handler(ce); + + return IRQ_HANDLED; +} + +static struct irqaction footbridge_timer_irq = { + .name = "dc21285_timer1", + .handler = timer1_interrupt, + .flags = IRQF_TIMER | IRQF_IRQPOLL, + .dev_id = &ckevt_dc21285, +}; + +/* + * Set up timer interrupt. + */ +void __init footbridge_timer_init(void) +{ + struct clock_event_device *ce = &ckevt_dc21285; + unsigned rate = DIV_ROUND_CLOSEST(mem_fclk_21285, 16); + + clocksource_register_hz(&cksrc_dc21285, rate); + + setup_irq(ce->irq, &footbridge_timer_irq); + + ce->cpumask = cpumask_of(smp_processor_id()); + clockevents_config_and_register(ce, rate, 0x4, 0xffffff); +} + +static u64 notrace footbridge_read_sched_clock(void) +{ + return ~*CSR_TIMER3_VALUE; +} + +void __init footbridge_sched_clock(void) +{ + unsigned rate = DIV_ROUND_CLOSEST(mem_fclk_21285, 16); + + *CSR_TIMER3_LOAD = 0; + *CSR_TIMER3_CLR = 0; + *CSR_TIMER3_CNTL = TIMER_CNTL_ENABLE | TIMER_CNTL_DIV16; + + sched_clock_register(footbridge_read_sched_clock, 24, rate); +} |