cLK/lk/platform/integrator/timer.c
2011-11-06 23:26:22 +00:00

102 lines
2.7 KiB
C

/*
* Copyright (c) 2008 Travis Geiselbrecht
*
* 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 <sys/types.h>
#include <err.h>
#include <kernel/thread.h>
#include <debug.h>
#include <platform.h>
#include <platform/interrupts.h>
#include <platform/timer.h>
#include <platform/integrator.h>
#include "platform_p.h"
static time_t system_time = 0;
static time_t tick_interval;
static uint32_t ticks_per_interval;
static platform_timer_callback t_callback;
static void *callback_arg;
status_t platform_set_periodic_timer(platform_timer_callback callback, void *arg, time_t interval)
{
#if 0
enter_critical_section();
t_callback = callback;
callback_arg = arg;
tick_interval = interval;
ticks_per_interval = interval * 32768 / 1000; // interval is in ms
OS_TIMER_CTRL_REG = 0; // stop it
OS_TIMER_TICK_VALUE_REG = ticks_per_interval;
OS_TIMER_CTRL_REG = (1<<3) | (1<<2) | (1<<1) | (1<<0);
exit_critical_section();
#endif
return NO_ERROR;
}
time_t current_time(void)
{
#if 0
time_t t;
uint32_t delta_ticks;
uint32_t delta_ticks2;
retry:
delta_ticks = OS_TIMER_TICK_COUNTER_REG;
t = system_time;
delta_ticks2 = OS_TIMER_TICK_COUNTER_REG;
if (delta_ticks2 > delta_ticks)
goto retry;
t += ((ticks_per_interval - delta_ticks2) * tick_interval) / ticks_per_interval;
return t;
#else
static time_t time = 0;
return time++;
#endif
}
static enum handler_return os_timer_tick(void *arg)
{
system_time += tick_interval;
// dprintf("os_timer_tick %d\n", system_time);
return t_callback(callback_arg, system_time);
}
void platform_init_timer(void)
{
#if 0
OS_TIMER_CTRL_REG = 0; // stop the timer if it's already running
register_int_handler(IRQ_OS_TIMER, &os_timer_tick, NULL);
unmask_interrupt(IRQ_OS_TIMER, NULL);
#endif
}