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/*
* Copyright (c) 2015 Eric Holland
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files
* (the "Software"), to deal in the Software without restriction,
* including without limitation the rights to use, copy, modify, merge,
* publish, distribute, sublicense, and/or sell copies of the Software,
* and to permit persons to whom the Software is furnished to do so,
* subject to the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#include <err.h>
#include <debug.h>
#include <trace.h>
#include <arch/arm/cm.h>
#include <platform.h>
#include <platform/nrf51.h>
#include <platform/system_nrf51.h>
#include <platform/timer.h>
#include <sys/types.h>
static volatile uint64_t ticks;
static uint32_t tick_rate = 0;
static uint32_t tick_rate_mhz = 0;
static lk_time_t tick_interval_ms;
static platform_timer_callback cb;
static void *cb_args;
typedef enum handler_return (*platform_timer_callback)(void *arg, lk_time_t now);
status_t platform_set_periodic_timer(platform_timer_callback callback, void *arg, lk_time_t interval)
{
cb = callback;
cb_args = arg;
tick_interval_ms = interval;
uint32_t ticks = tick_rate / ( 1000 / interval );
NRF_CLOCK->LFCLKSRC = CLOCK_LFCLKSRC_SRC_Xtal << CLOCK_LFCLKSRC_SRC_Pos;
NRF_CLOCK->TASKS_LFCLKSTART = 1;
NRF_RTC1->PRESCALER = ticks;
NRF_RTC1->INTENSET = RTC_INTENSET_TICK_Enabled << RTC_INTENSET_TICK_Pos;
NRF_RTC1->EVENTS_TICK = 0;
NRF_RTC1->TASKS_START = 1;
NVIC_EnableIRQ(RTC1_IRQn);
return NO_ERROR;
}
lk_time_t current_time(void)
{
uint64_t t;
do {
t = ticks;
} while (ticks != t);
return t * tick_interval_ms;
}
lk_bigtime_t current_time_hires(void)
{
return current_time() * 1000;
}
void nrf51_RTC1_IRQ(void)
{
ticks++;
arm_cm_irq_entry();
NRF_RTC1->EVENTS_TICK = 0;
bool resched = false;
if (cb) {
lk_time_t now = current_time();
if (cb(cb_args, now) == INT_RESCHEDULE)
resched = true;
}
arm_cm_irq_exit(resched);
}
void arm_cm_systick_init(uint32_t mhz)
{
tick_rate = mhz;
tick_rate_mhz = mhz / 1000000;
}
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