timer_at91.h

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#ifndef DRV_AT91_TIMER_H
#define DRV_AT91_TIMER_H

#include <hw/hw_cpufreq.h>     /* CPU_FREQ */

#include "cfg/cfg_timer.h"     /* CONFIG_TIMER */
#include <cfg/compiler.h>      /* uint8_t */
#include <cfg/macros.h>        /* BV */

#include <io/arm.h>

#define TIMER_ON_PIT 1  

#define TIMER_DEFAULT TIMER_ON_PIT  

/*
 * Hardware dependent timer initialization.
 */
#if (CONFIG_TIMER == TIMER_ON_PIT)

    /*
     * On ARM all system IRQs are handled by the sysirq_dispatcher, so the actual
     * timer handler can be treated like any other normal routine.
     */
    #define DEFINE_TIMER_ISR    void timer_handler(void);   \
                    void timer_handler(void)

    #define TIMER_TICKS_PER_SEC  1000
    #define TIMER_HW_CNT         (CPU_FREQ / (16 * TIMER_TICKS_PER_SEC) - 1)

    #define TIMER_HW_HPTICKS_PER_SEC (CPU_FREQ / 16)

    typedef uint32_t hptime_t;
    #define SIZEOF_HPTIME_T 4

    INLINE void timer_hw_irq(void)
    {
        /* Reset counters, this is needed to reset timer and interrupt flags */
        uint32_t dummy = PIVR;
        (void) dummy;
    }

    INLINE bool timer_hw_triggered(void)
    {
        return PIT_SR & BV(PITS);
    }

    INLINE hptime_t timer_hw_hpread(void)
    {
        /* In the upper part of PIT_PIIR there is unused data */
        return PIIR & CPIV_MASK;
    }

#else

    #error Unimplemented value for CONFIG_TIMER
#endif /* CONFIG_TIMER */

void timer_hw_init(void);


#endif /* DRV_TIMER_AT91_H */