Files
lk/platform/at32ap7/timer.c
2010-07-07 02:34:47 -07:00

134 lines
3.5 KiB
C

/*
* Copyright (c) 2009-2010 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 <reg.h>
#include <err.h>
#include <kernel/thread.h>
#include <debug.h>
#include <platform.h>
#include <platform/interrupts.h>
#include <platform/timer.h>
#include <platform/at32ap7.h>
#include "platform_p.h"
#define LOCAL_TRACE 0
#define NUM_TMR 6
#define TMR_FREQ (32768)
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;
static inline addr_t TMR_REG_ADDR(unsigned int tmr, unsigned int reg)
{
return ((tmr >= 3) ? (TC1_BASE + reg + 0x40 * (tmr - 3)) : (TC0_BASE + reg + 0x40 * (tmr)));
}
#define TMR_REG(tmr, reg) (*REG32(TMR_REG_ADDR(tmr, reg)))
static enum handler_return os_timer_tick(void *arg)
{
uint32_t hole = TMR_REG(0, TC_SR); // gotta read the status register to clear the state
hole = hole;
system_time += tick_interval;
// printf("os_timer_tick %d\n", system_time);
if (!t_callback)
return INT_NO_RESCHEDULE;
return t_callback(callback_arg, system_time);
}
status_t platform_set_periodic_timer(platform_timer_callback callback, void *arg, time_t interval)
{
enter_critical_section();
LTRACEF("callback %p, arg %p, interval %d\n", callback, arg, interval);
t_callback = callback;
callback_arg = arg;
tick_interval = interval;
ticks_per_interval = interval * TMR_FREQ / 1000; // interval is in ms
TMR_REG(0, TC_CCR) = (1<<1); // CLKDIS
TMR_REG(0, TC_CMR) = (1<<14); // CPCTRG
TMR_REG(0, TC_RC) = interval;
TMR_REG(0, TC_IER) = (1<<4);
TMR_REG(0, TC_CCR) = (1<<0); // CLKEN
TMR_REG(0, TC_CCR) |= (1<<2); // SWTRG
register_int_handler(INT_TC00, &os_timer_tick, NULL);
unmask_interrupt(INT_TC00);
exit_critical_section();
return NO_ERROR;
}
time_t current_time(void)
{
time_t t;
uint32_t delta_ticks;
uint32_t delta_ticks2;
retry:
delta_ticks = TMR_REG(0, TC_CV);
t = system_time;
delta_ticks2 = TMR_REG(0, TC_CV);
if (delta_ticks2 < delta_ticks)
goto retry;
t += (delta_ticks2 * tick_interval) / ticks_per_interval;
return t;
}
bigtime_t current_time_hires(void)
{
return current_time() * 1000ULL;
}
void platform_init_timer(void)
{
TRACE_ENTRY;
platform_set_clock_enable(CLOCK_TC0, true);
platform_set_clock_enable(CLOCK_TC1, true);
// disable all the clocks
unsigned int i;
for (i = 0; i < NUM_TMR; i++) {
TMR_REG(i, TC_CCR) = (1<<1); // CLKDIS
TMR_REG(i, TC_IDR) = 0xf; // disable all interrupts
}
TRACE_EXIT;
}