Add clocksource and clockevent support for the timer/counter unit on JZ4750D SoCs. Signed-off-by: Antony Pavlov <antonynpavlov@xxxxxxxxx> --- arch/mips/jz4750d/time.c | 145 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 145 insertions(+) create mode 100644 arch/mips/jz4750d/time.c diff --git a/arch/mips/jz4750d/time.c b/arch/mips/jz4750d/time.c new file mode 100644 index 0000000..5df91e0 --- /dev/null +++ b/arch/mips/jz4750d/time.c @@ -0,0 +1,145 @@ +/* + * Copyright (C) 2012, Antony Pavlov <antonynpavlov@xxxxxxxxx> + * JZ4750D platform time support + * + * based on JZ4740 platform time support + * Copyright (C) 2010, Lars-Peter Clausen <lars@xxxxxxxxxx> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + * + */ + +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/time.h> + +#include <linux/clockchips.h> + +#include <asm/time.h> + +#include "clock.h" +#include "timer.h" + +#define TIMER_CLOCKEVENT 5 + +static uint16_t jz4750d_jiffies_per_tick; + +static cycle_t jz4750d_clocksource_read(struct clocksource *cs) +{ + return (cycle_t)jz4750d_ostimer_get_count(); +} + +static struct clocksource jz4750d_clocksource = { + .name = "jz4750d-timer", + .rating = 200, + .read = jz4750d_clocksource_read, + .mask = CLOCKSOURCE_MASK(32), + .flags = CLOCK_SOURCE_WATCHDOG, +}; + +static irqreturn_t jz4750d_clockevent_irq(int irq, void *devid) +{ + struct clock_event_device *cd = devid; + + jz4750d_timer_ack_full(TIMER_CLOCKEVENT); + + if (cd->mode != CLOCK_EVT_MODE_PERIODIC) + jz4750d_timer_disable(TIMER_CLOCKEVENT); + + cd->event_handler(cd); + + return IRQ_HANDLED; +} + +static void jz4750d_clockevent_set_mode(enum clock_event_mode mode, + struct clock_event_device *cd) +{ + switch (mode) { + case CLOCK_EVT_MODE_PERIODIC: + jz4750d_timer_set_count(TIMER_CLOCKEVENT, 0); + jz4750d_timer_set_period(TIMER_CLOCKEVENT, jz4750d_jiffies_per_tick); + case CLOCK_EVT_MODE_RESUME: + jz4750d_timer_irq_full_enable(TIMER_CLOCKEVENT); + jz4750d_timer_enable(TIMER_CLOCKEVENT); + break; + case CLOCK_EVT_MODE_ONESHOT: + case CLOCK_EVT_MODE_SHUTDOWN: + jz4750d_timer_disable(TIMER_CLOCKEVENT); + break; + default: + break; + } +} + +static int jz4750d_clockevent_set_next(unsigned long evt, + struct clock_event_device *cd) +{ + jz4750d_timer_set_count(TIMER_CLOCKEVENT, 0); + jz4750d_timer_set_period(TIMER_CLOCKEVENT, evt); + jz4750d_timer_enable(TIMER_CLOCKEVENT); + + return 0; +} + +static struct clock_event_device jz4750d_clockevent = { + .name = "jz4750d-timer", + .features = CLOCK_EVT_FEAT_PERIODIC, + .set_next_event = jz4750d_clockevent_set_next, + .set_mode = jz4750d_clockevent_set_mode, + .rating = 200, + .irq = JZ4750D_IRQ_TCU1, +}; + +static struct irqaction timer_irqaction = { + .handler = jz4750d_clockevent_irq, + .flags = IRQF_DISABLED | IRQF_PERCPU | IRQF_TIMER, + .name = "jz4750d-timerirq", + .dev_id = &jz4750d_clockevent, +}; + +void __init plat_time_init(void) +{ + int ret; + uint32_t clk_rate; + + jz4750d_timer_init(); + + clk_rate = jz4750d_clock_bdata.ext_rate >> 4; + jz4750d_jiffies_per_tick = DIV_ROUND_CLOSEST(clk_rate, HZ); + + clockevent_set_clock(&jz4750d_clockevent, clk_rate); + jz4750d_clockevent.min_delta_ns = + clockevent_delta2ns(100, &jz4750d_clockevent); + jz4750d_clockevent.max_delta_ns = + clockevent_delta2ns(0xffff, &jz4750d_clockevent); + jz4750d_clockevent.cpumask = cpumask_of(0); + + jz4750d_timer_irq_full_disable(TIMER_CLOCKEVENT); + + clockevents_register_device(&jz4750d_clockevent); + + ret = clocksource_register_hz(&jz4750d_clocksource, clk_rate); + + if (ret) + printk(KERN_ERR "Failed to register clocksource: %d\n", ret); + + setup_irq(JZ4750D_IRQ_TCU1, &timer_irqaction); + + jz4750d_timer_set_ctrl(TIMER_CLOCKEVENT, JZ_TIMER_CTRL_PRESCALE_16 + | JZ_TIMER_CTRL_SRC_EXT); + jz4750d_ostimer_set_ctrl(JZ_OSTIMER_CTRL_PRESCALE_16 + | JZ_OSTIMER_CTRL_SRC_EXT); + + jz4750d_timer_set_period(TIMER_CLOCKEVENT, jz4750d_jiffies_per_tick); + jz4750d_timer_irq_full_enable(TIMER_CLOCKEVENT); + + jz4750d_ostimer_set_period(0xffffffff); + + jz4750d_timer_enable(TIMER_CLOCKEVENT); + jz4750d_timer_start(TIMER_CLOCKEVENT); + jz4750d_ostimer_enable(); + jz4750d_ostimer_start(); +} -- 1.7.10.4