OpenModem/bertos/cpu/arm/drv/timer_at91.c
2014-04-03 22:21:37 +02:00

81 lines
2.3 KiB
C

/**
* \file
* <!--
* This file is part of BeRTOS.
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*
* \author Francesco Sacchi <batt@develer.com>
*
* \brief Low-level timer module for Atmel AT91 (inplementation).
*/
#include "timer_at91.h"
#include <io/arm.h>
#include "sysirq_at91.h"
#include <cfg/macros.h> // BV()
#include <cfg/module.h>
#include <cpu/irq.h>
#include <cpu/types.h>
/** HW dependent timer initialization */
#if (CONFIG_TIMER == TIMER_ON_PIT)
ISR_PROTO_CONTEXT_SWITCH(timer_handler);
void timer_hw_init(void)
{
sysirq_init();
cpu_flags_t flags;
MOD_CHECK(sysirq);
IRQ_SAVE_DISABLE(flags);
PIT_MR = TIMER_HW_CNT;
/* Register system interrupt handler. */
sysirq_setHandler(SYSIRQ_PIT, timer_handler);
/* Enable interval timer and interval timer interrupts */
PIT_MR |= BV(PITEN);
sysirq_setEnable(SYSIRQ_PIT, true);
/* Reset counters, this is needed to start timer and interrupt flags */
uint32_t dummy = PIVR;
(void) dummy;
IRQ_RESTORE(flags);
}
#else
#error Unimplemented value for CONFIG_TIMER
#endif /* CONFIG_TIMER */