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/**
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 * @file
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 * @brief MIPS build-in timer
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 *
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 * @date 04.07.2012
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 * @author Anton Bondarev
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 */
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#include <stdint.h>
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#include <asm/mipsregs.h>
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#include <framework/mod/options.h>
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#include <hal/clock.h>
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#include <hal/system.h>
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#include <kernel/irq.h>
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#include <kernel/time/clock_source.h>
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#include <kernel/time/time.h>
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#define CYC_PER_TICK       OPTION_GET(NUMBER, cyc_per_tick)
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#define TIMER_IRQ_INTERVAL (SYS_CLOCK / (CYC_PER_TICK * JIFFIES_PERIOD))
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static irq_return_t clock_handler(unsigned int irq_nr, void *dev_id) {
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	mips_write_c0_compare(TIMER_IRQ_INTERVAL); /* this lowers irq line */
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	mips_write_c0_count(0);
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	clock_tick_handler(dev_id);
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	return IRQ_HANDLED;
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}
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static cycle_t mips_clk_read(struct clock_source *cs) {
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	return (cycle_t)mips_read_c0_count();
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}
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static int mips_clock_setup(struct clock_source *cs) {
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	mips_write_c0_compare(TIMER_IRQ_INTERVAL);
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	mips_write_c0_count(0);
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	return 0;
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}
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static struct time_event_device mips_event_device = {
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    .set_periodic = mips_clock_setup,
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    .name = "mips_clk",
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    .irq_nr = MIPS_IRQN_TIMER,
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};
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static struct time_counter_device mips_counter_device = {
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    .read = mips_clk_read,
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    .cycle_hz = SYS_CLOCK,
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};
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static int mips_clock_init(struct clock_source *cs) {
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	return irq_attach(MIPS_IRQN_TIMER, clock_handler, 0, cs, "mips_clk");
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}
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CLOCK_SOURCE_DEF(mips_clk, mips_clock_init, NULL, &mips_event_device,
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    &mips_counter_device);
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