nes-proj/arch/platform/jn516x/dev/clock.c
2017-10-12 23:57:38 +02:00

298 lines
8.8 KiB
C

/*
* Copyright (c) 2014, SICS Swedish ICT.
* 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
* Tickless clock implementation for NXP jn516x.
* \author
* Beshr Al Nahas <beshr@sics.se>
* Atis Elsts <atis.elsts@sics.se>
*
*/
#include <AppHardwareApi.h>
#include <PeripheralRegs.h>
#include "contiki.h"
#include "sys/clock.h"
#include "sys/etimer.h"
#include "rtimer-arch.h"
#include "dev/watchdog.h"
#define DEBUG 0
#if DEBUG
#include <stdio.h>
#define PRINTF(...) printf(__VA_ARGS__)
#else
#define PRINTF(...)
#endif
#define CLOCK_TIMER E_AHI_TIMER_1
#define CLOCK_TIMER_ISR_DEV E_AHI_DEVICE_TIMER1
#define OVERFLOW_TIMER E_AHI_TIMER_0
#define OVERFLOW_TIMER_ISR_DEV E_AHI_DEVICE_TIMER0
/* 16Mhz / 2^10 = 15.625 kHz */
#define CLOCK_PRESCALE 10
#define PRESCALED_TICKS_PER_SECOND 15625
/* 8ms tick --> overflow after ~397.7 days */
#define CLOCK_INTERVAL 125
/* Max schedulable number of ticks.
* Must not be more than:
* 0xffff / (16'000'000 / (1 << CLOCK_PRESCALE) / CLOCK_SECOND)
*/
#define CLOCK_MAX_SCHEDULABLE_TICKS 520
/* Min guard time an etimer can be scheduled before an rtimer */
#define CLOCK_RTIMER_GUARD_TIME US_TO_RTIMERTICKS(16)
/* Clock tick expressed as rtimer ticks */
#define CLOCK_TICK ((1 << CLOCK_PRESCALE) * CLOCK_INTERVAL)
#define RTIMER_OVERFLOW_PRESCALED 4194304 /* = 0x100000000 / (2^CLOCK_PRESCALE) */
#define RTIMER_OVERFLOW_REMAINDER 54 /* in prescaled ticks, per one overflow */
#define CLOCK_LT(a, b) ((int32_t)((a)-(b)) < 0)
/*---------------------------------------------------------------------------*/
static uint32_t
clock(void)
{
/* same as rtimer_arch_now() */
return u32AHI_TickTimerRead();
}
/*---------------------------------------------------------------------------*/
static uint32_t
check_rtimer_overflow(rtimer_clock_t now)
{
static rtimer_clock_t last_rtimer_ticks;
static uint32_t clock_ticks_remainder;
static uint32_t clock_ticks_base;
if(last_rtimer_ticks > now) {
clock_ticks_base += RTIMER_OVERFLOW_PRESCALED / CLOCK_INTERVAL;
clock_ticks_remainder += RTIMER_OVERFLOW_REMAINDER;
if(clock_ticks_remainder > CLOCK_INTERVAL) {
clock_ticks_remainder -= CLOCK_INTERVAL;
clock_ticks_base += 1;
}
}
last_rtimer_ticks = now;
return clock_ticks_base;
}
/*---------------------------------------------------------------------------*/
static void
check_etimers(void)
{
if(etimer_pending()) {
clock_time_t now = clock_time();
if(!CLOCK_LT(now, etimer_next_expiration_time())) {
etimer_request_poll();
}
}
process_nevents();
}
/*---------------------------------------------------------------------------*/
void
clockTimerISR(uint32 u32Device, uint32 u32ItemBitmap)
{
if(u32Device != CLOCK_TIMER_ISR_DEV && u32Device != OVERFLOW_TIMER_ISR_DEV) {
return;
}
if(u32Device == CLOCK_TIMER_ISR_DEV) {
check_etimers();
}
if(u32Device == OVERFLOW_TIMER_ISR_DEV) {
check_rtimer_overflow(clock());
}
}
/*---------------------------------------------------------------------------*/
void
clock_arch_calibrate(void)
{
bAHI_SetClockRate(E_AHI_XTAL_32MHZ);
/* Wait for oscillator to stabilise */
while(bAHI_GetClkSource() == 1) ;
while(bAHI_Clock32MHzStable() == 0) ;
vAHI_OptimiseWaitStates();
/* Turn on SPI master */
vREG_SysWrite(REG_SYS_PWR_CTRL, u32REG_SysRead(REG_SYS_PWR_CTRL)
| REG_SYSCTRL_PWRCTRL_SPIMEN_MASK);
}
/*---------------------------------------------------------------------------*/
void
clock_arch_init(int is_reinitialization)
{
/* initialize etimer interrupt timer */
vAHI_TimerEnable(CLOCK_TIMER, CLOCK_PRESCALE, 0, 1, 0);
vAHI_TimerClockSelect(CLOCK_TIMER, 0, 0);
vAHI_TimerConfigureOutputs(CLOCK_TIMER, 0, 1);
vAHI_TimerDIOControl(CLOCK_TIMER, 0);
vAHI_Timer1RegisterCallback(clockTimerISR);
/* initialize and start rtimer overflow timer */
vAHI_TimerEnable(OVERFLOW_TIMER, CLOCK_PRESCALE, 0, 1, 0);
vAHI_TimerClockSelect(OVERFLOW_TIMER, 0, 0);
vAHI_TimerConfigureOutputs(OVERFLOW_TIMER, 0, 1);
vAHI_TimerDIOControl(OVERFLOW_TIMER, 0);
vAHI_Timer0RegisterCallback(clockTimerISR);
vAHI_TimerStartRepeat(OVERFLOW_TIMER, 0, PRESCALED_TICKS_PER_SECOND * 4);
if(is_reinitialization) {
/* check if the etimer has overflowed (useful when this is executed after sleep */
check_rtimer_overflow(clock());
}
}
/*---------------------------------------------------------------------------*/
void
clock_init(void)
{
/* gMAC_u8MaxBuffers = 2; */
#ifdef JENNIC_CHIP_FAMILY_JN516x
/* Turn off debugger */
*(volatile uint32 *)0x020000a0 = 0;
#endif
clock_arch_calibrate();
/* setup clock mode and interrupt handler */
clock_arch_init(0);
}
/*---------------------------------------------------------------------------*/
clock_time_t
clock_time(void)
{
uint32_t now = clock();
clock_time_t base = check_rtimer_overflow(now);
return base + now / CLOCK_TICK;
}
/*---------------------------------------------------------------------------*/
/**
* Delay the CPU for a multiple of 0.0625 us.
*/
void
clock_delay_usec(uint16_t dt)
{
uint32_t end = clock() + dt;
/* Note: this does not call watchdog periodic() */
while(CLOCK_LT(clock(), end));
}
/*---------------------------------------------------------------------------*/
/**
* Delay the CPU for a multiple of 8 us.
*/
void
clock_delay(unsigned int dt)
{
uint32_t end = clock() + dt * 128;
while(CLOCK_LT(clock(), end)) {
watchdog_periodic();
}
}
/*---------------------------------------------------------------------------*/
/**
* Wait for a multiple of 10 ms.
*
*/
void
clock_wait(clock_time_t t)
{
clock_time_t end = clock_time() + t;
while(CLOCK_LT(clock_time(), end)) {
watchdog_periodic();
}
}
/*---------------------------------------------------------------------------*/
unsigned long
clock_seconds(void)
{
return clock_time() / CLOCK_SECOND;
}
/*---------------------------------------------------------------------------*/
clock_time_t
clock_arch_time_to_etimer(void)
{
clock_time_t time_to_etimer;
if(etimer_pending()) {
time_to_etimer = etimer_next_expiration_time() - clock_time();
if((int32_t)time_to_etimer < 0) {
time_to_etimer = 0;
}
} else {
/* no active etimers */
time_to_etimer = (clock_time_t)-1;
}
return time_to_etimer;
}
/*---------------------------------------------------------------------------*/
void
clock_arch_schedule_interrupt(clock_time_t time_to_etimer, rtimer_clock_t ticks_to_rtimer)
{
if(time_to_etimer > CLOCK_MAX_SCHEDULABLE_TICKS) {
time_to_etimer = CLOCK_MAX_SCHEDULABLE_TICKS;
}
time_to_etimer *= CLOCK_INTERVAL;
if(ticks_to_rtimer != (rtimer_clock_t)-1) {
/* if the next rtimer is close enough to the etimer... */
rtimer_clock_t ticks_to_etimer = time_to_etimer * (1 << CLOCK_PRESCALE);
#if RTIMER_USE_32KHZ
ticks_to_rtimer = (uint64_t)ticks_to_rtimer * (F_CPU / 2) / RTIMER_SECOND;
#endif
if(!CLOCK_LT(ticks_to_rtimer, ticks_to_etimer)
&& CLOCK_LT(ticks_to_rtimer, ticks_to_etimer + CLOCK_RTIMER_GUARD_TIME)) {
/* ..then schedule the etimer after the rtimer */
time_to_etimer += 2;
}
}
/* interrupt will not be generated if 0 is passed as the parameter */
if(time_to_etimer == 0) {
time_to_etimer = 1;
}
vAHI_TimerStartSingleShot(CLOCK_TIMER, 0, time_to_etimer);
}
/*---------------------------------------------------------------------------*/