osd-contiki/cpu/avr/rtimer-arch.c
Ralf Schlatterbeck e88f60feee Make HW timer for contiki rtimer configurable
... and configure osd platform to use timer 5. With the new
configuration we can use timer 3 for generating hardware PWM.
2014-05-31 16:17:07 +02:00

293 lines
8.8 KiB
C

/*
* Copyright (c) 2007, Swedish Institute of Computer Science.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* This file is part of the Contiki operating system.
*
*/
/**
* \file
* AVR-specific rtimer code
* Defaults to Timer3 for those ATMEGAs that have it.
* If Timer3 not present Timer1 will be used.
* \author
* Fredrik Osterlind <fros@sics.se>
* Joakim Eriksson <joakime@sics.se>
*/
/* OBS: 8 seconds maximum time! */
#include <avr/io.h>
#include <avr/interrupt.h>
#include <stdio.h>
#include "sys/energest.h"
#include "sys/rtimer.h"
#include "rtimer-arch.h"
#if defined(__AVR_ATmega1284P__)
//Has no 'C', so we just set it to B. The code doesn't really use C so this
//is safe to do but lets it compile. Probably should enable the warning if
//it is ever used on other platforms.
//#warning no OCIE3C in timer3 architecture, hopefully it won't be needed!
#define OCIE3C OCIE3B
#define OCF3C OCF3B
#define PLAT_TCCRC PLAT_TCCRB
#endif
#if defined(__AVR_ATmega1281__) || defined(__AVR_AT90USB1287__) || defined(__AVR_ATmega128RFA1__)
#endif
#if defined(__AVR_ATmega328P__) || defined(__AVR_ATmega644__)
//Has no 'C', so we just set it to B. The code doesn't really use C so this
//is safe to do but lets it compile.
#define OCIE1C OCIE1B
#define OCF1C OCF1B
#define PLAT_TCCRC PLAT_TCCRB
#endif
/* Track flow through rtimer interrupts*/
#if DEBUGFLOWSIZE&&0
extern uint8_t debugflowsize,debugflow[DEBUGFLOWSIZE];
#define DEBUGFLOW(c) if (debugflowsize<(DEBUGFLOWSIZE-1)) debugflow[debugflowsize++]=c
#else
#define DEBUGFLOW(c)
#endif
/*---------------------------------------------------------------------------*/
#if RTIMER_ARCH_PRESCALER
ISR (PLAT_VECT) {
DEBUGFLOW('/');
ENERGEST_ON(ENERGEST_TYPE_IRQ);
/* Disable rtimer interrupts */
PLAT_TIMSK &=
~( (1 << PLAT_OCIEA)
| (1 << PLAT_OCIEB)
| (1 << PLAT_OCIEC)
| (1 << PLAT_TOIE)
| (1 << PLAT_ICIE)
);
#if RTIMER_CONF_NESTED_INTERRUPTS
/* Enable nested interrupts. Allows radio interrupt during rtimer interrupt. */
/* All interrupts are enabled including recursive rtimer, so use with caution */
sei();
#endif
/* Call rtimer callback */
rtimer_run_next();
ENERGEST_OFF(ENERGEST_TYPE_IRQ);
DEBUGFLOW('\\');
}
#endif
/*---------------------------------------------------------------------------*/
void
rtimer_arch_init(void)
{
#if RTIMER_ARCH_PRESCALER
/* Disable interrupts (store old state) */
uint8_t sreg;
sreg = SREG;
cli ();
/* Disable all timer functions */
PLAT_TIMSK &=
~( (1 << PLAT_OCIEA)
| (1 << PLAT_OCIEB)
| (1 << PLAT_OCIEC)
| (1 << PLAT_TOIE)
| (1 << PLAT_ICIE)
);
/* Write 1s to clear existing timer function flags */
PLAT_TIFR |=
( (1 << PLAT_ICF)
| (1 << PLAT_OCFA)
| (1 << PLAT_OCFB)
| (1 << PLAT_OCFC)
| (1 << PLAT_TOV)
);
/* Default timer behaviour */
PLAT_TCCRA = 0;
PLAT_TCCRB = 0;
PLAT_TCCRC = 0;
/* Reset counter */
PLAT_TCNT = 0;
#if RTIMER_ARCH_PRESCALER==1024
PLAT_TCCRB |= 5;
#elif RTIMER_ARCH_PRESCALER==256
PLAT_TCCRB |= 4;
#elif RTIMER_ARCH_PRESCALER==64
PLAT_TCCRB |= 3;
#elif RTIMER_ARCH_PRESCALER==8
PLAT_TCCRB |= 2;
#elif RTIMER_ARCH_PRESCALER==1
PLAT_TCCRB |= 1;
#else
#error Timer PRESCALER factor not supported.
#endif
/* Restore interrupt state */
SREG = sreg;
#endif /* RTIMER_ARCH_PRESCALER */
}
/*---------------------------------------------------------------------------*/
void
rtimer_arch_schedule(rtimer_clock_t t)
{
#if RTIMER_ARCH_PRESCALER
/* Disable interrupts (store old state) */
uint8_t sreg;
sreg = SREG;
cli ();
DEBUGFLOW(':');
/* Set compare register */
PLAT_OCRA = t;
/* Write 1s to clear all timer function flags */
PLAT_TIFR |=
( (1 << PLAT_ICF)
| (1 << PLAT_OCFA)
| (1 << PLAT_OCFB)
| (1 << PLAT_OCFC)
| (1 << PLAT_TOV)
);
/* Enable interrupt on OCRXA match */
PLAT_TIMSK |= (1 << PLAT_OCIEA);
/* Restore interrupt state */
SREG = sreg;
#endif /* RTIMER_ARCH_PRESCALER */
}
#if RDC_CONF_MCU_SLEEP
/*---------------------------------------------------------------------------*/
void
rtimer_arch_sleep(rtimer_clock_t howlong)
{
/* Deep Sleep for howlong rtimer ticks. This will stop all timers except
* for TIMER2 which can be clocked using an external crystal.
* Unfortunately this is an 8 bit timer; a lower prescaler gives higher
* precision but smaller maximum sleep time.
* Here a maximum 128msec (contikimac 8Hz channel check sleep) is assumed.
* The rtimer and system clocks are adjusted to reflect the sleep time.
*/
#include <avr/sleep.h>
#include <dev/watchdog.h>
uint32_t longhowlong;
#if AVR_CONF_USE32KCRYSTAL
/* Save TIMER2 configuration if clock.c is using it */
uint8_t savedTCNT2=TCNT2, savedTCCR2A=TCCR2A, savedTCCR2B = TCCR2B, savedOCR2A = OCR2A;
#endif
cli();
watchdog_stop();
set_sleep_mode(SLEEP_MODE_PWR_SAVE);
/* Set TIMER2 clock asynchronus from external source, CTC mode */
ASSR |= (1 << AS2);
TCCR2A =(1<<WGM21);
/* Set prescaler and TIMER2 output compare register */
#if 0 //Prescale by 1024 - 32 ticks/sec, 8 seconds max sleep
TCCR2B =((1<<CS22)|(1<<CS21)|(1<<CS20));
longhowlong=howlong*32UL;
#elif 0 // Prescale by 256 - 128 ticks/sec, 2 seconds max sleep
TCCR2B =((1<<CS22)|(1<<CS21)|(0<<CS20));
longhowlong=howlong*128UL;
#elif 0 // Prescale by 128 - 256 ticks/sec, 1 seconds max sleep
TCCR2B =((1<<CS22)|(0<<CS21)|(1<<CS20));
longhowlong=howlong*256UL;
#elif 0 // Prescale by 64 - 512 ticks/sec, 500 msec max sleep
TCCR2B =((1<<CS22)|(0<<CS21)|(0<<CS20));
longhowlong=howlong*512UL;
#elif 1 // Prescale by 32 - 1024 ticks/sec, 250 msec max sleep
TCCR2B =((0<<CS22)|(1<<CS21)|(1<<CS20));
longhowlong=howlong*1024UL;
#elif 0 // Prescale by 8 - 4096 ticks/sec, 62.5 msec max sleep
TCCR2B =((0<<CS22)|(1<<CS21)|(0<<CS20));
longhowlong=howlong*4096UL;
#else // No Prescale - 32768 ticks/sec, 7.8 msec max sleep
TCCR2B =((0<<CS22)|(0<<CS21)|(1<<CS20));
longhowlong=howlong*32768UL;
#endif
OCR2A = longhowlong/RTIMER_ARCH_SECOND;
/* Reset timer count, wait for the write (which assures TCCR2x and OCR2A are finished) */
TCNT2 = 0;
while(ASSR & (1 << TCN2UB));
/* Enable TIMER2 output compare interrupt, sleep mode and sleep */
TIMSK2 |= (1 << OCIE2A);
SMCR |= (1 << SE);
sei();
ENERGEST_OFF(ENERGEST_TYPE_CPU);
if (OCR2A) sleep_mode();
//...zzZZZzz...Ding!//
/* Disable sleep mode after wakeup, so random code cant trigger sleep */
SMCR &= ~(1 << SE);
/* Adjust rtimer ticks if rtimer is enabled. TIMER3 is preferred, else TIMER1 */
#if RTIMER_ARCH_PRESCALER
PLAT_TCNT += howlong;
#endif
ENERGEST_ON(ENERGEST_TYPE_CPU);
#if AVR_CONF_USE32KCRYSTAL
/* Restore clock.c configuration */
cli();
TCCR2A = savedTCCR2A;
TCCR2B = savedTCCR2B;
OCR2A = savedOCR2A;
TCNT2 = savedTCNT2;
sei();
#else
/* Disable TIMER2 interrupt */
TIMSK2 &= ~(1 << OCIE2A);
#endif
watchdog_start();
/* Adjust clock.c for the time spent sleeping */
longhowlong=CLOCK_CONF_SECOND;
longhowlong*=howlong;
clock_adjust_ticks(longhowlong/RTIMER_ARCH_SECOND);
}
#if !AVR_CONF_USE32KCRYSTAL
/*---------------------------------------------------------------------------*/
/* TIMER2 Interrupt service */
ISR(TIMER2_COMPA_vect)
{
// TIMSK2 &= ~(1 << OCIE2A); //Just one interrupt needed for waking
}
#endif /* !AVR_CONF_USE32KCRYSTAL */
#endif /* RDC_CONF_MCU_SLEEP */