/*
* Copyright (C) 2016 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <cpu/cpuMath.h>
#include <plat/gpio.h>
#include <plat/usart.h>
#include <plat/cmsis.h>
#include <plat/pwr.h>
#include <plat/rtc.h>
#include <plat/plat.h>
#include <plat/exti.h>
#include <plat/wdt.h>
#include <plat/dma.h>
#include <stdbool.h>
#include <stdio.h>
#include <string.h>
#include <pthread.h>
#include <unistd.h>
#include <platform.h>
#include <seos.h>
#include <heap.h>
#include <timer.h>
#include <usart.h>
#include <gpio.h>
#include <mpu.h>
#include <cpu.h>
#include <hostIntf.h>
#include <atomic.h>
#include <hostIntf.h>
#include <nanohubPacket.h>
#include <sensType.h>
#include <variant/variant.h>
struct StmDbgmcu {
volatile uint32_t IDCODE;
volatile uint32_t CR;
volatile uint32_t APB1FZ;
volatile uint32_t APB2FZ;
};
struct StmTim {
volatile uint16_t CR1;
uint8_t unused0[2];
volatile uint16_t CR2;
uint8_t unused1[2];
volatile uint16_t SMCR;
uint8_t unused2[2];
volatile uint16_t DIER;
uint8_t unused3[2];
volatile uint16_t SR;
uint8_t unused4[2];
volatile uint16_t EGR;
uint8_t unused5[2];
volatile uint16_t CCMR1;
uint8_t unused6[2];
volatile uint16_t CCMR2;
uint8_t unused7[2];
volatile uint16_t CCER;
uint8_t unused8[2];
volatile uint32_t CNT;
volatile uint16_t PSC;
uint8_t unused9[2];
volatile uint32_t ARR;
volatile uint16_t RCR;
uint8_t unused10[2];
volatile uint32_t CCR1;
volatile uint32_t CCR2;
volatile uint32_t CCR3;
volatile uint32_t CCR4;
volatile uint16_t BDTR;
uint8_t unused11[2];
volatile uint16_t DCR;
uint8_t unused12[2];
volatile uint16_t DMAR;
uint8_t unused13[2];
volatile uint16_t OR;
uint8_t unused14[2];
};
#define TIM2 ((struct StmTim*)TIM2_BASE)
#define DBGMCU ((struct StmDbgmcu*)DBGMCU_BASE)
/* RTC bit defintions */
#define TIM_EGR_UG 0x0001
/* DBGMCU bit definition */
#define DBG_SLEEP 0x00000001
#define DBG_STOP 0x00000002
#define DBG_STANDBY 0x00000004
#ifdef DEBUG_UART_UNITNO
static struct usart mDbgUart;
#endif
#ifdef DEBUG_LOG_EVT
#ifndef EARLY_LOG_BUF_SIZE
#define EARLY_LOG_BUF_SIZE 2048
#endif
#define HOSTINTF_HEADER_SIZE 4
uint8_t *mEarlyLogBuffer;
uint16_t mEarlyLogBufferCnt;
uint16_t mEarlyLogBufferOffset;
bool mLateBoot;
#endif
static uint64_t mTimeAccumulated = 0;
static uint32_t mMaxJitterPpm = 0, mMaxDriftPpm = 0, mMaxErrTotalPpm = 0;
static uint32_t mSleepDevsToKeepAlive = 0;
static uint64_t mWakeupTime = 0;
static uint32_t mDevsMaxWakeTime[PLAT_MAX_SLEEP_DEVS] = {0,};
void platUninitialize(void)
{
#ifdef DEBUG_UART_UNITNO
usartClose(&mDbgUart);
#endif
}
void *platLogAllocUserData()
{
#if defined(DEBUG_LOG_EVT)
struct HostIntfDataBuffer *userData = NULL;
if (mLateBoot) {
userData = heapAlloc(sizeof(struct HostIntfDataBuffer));
} else if (mEarlyLogBufferOffset < EARLY_LOG_BUF_SIZE - HOSTINTF_HEADER_SIZE) {
userData = (struct HostIntfDataBuffer *)(mEarlyLogBuffer + mEarlyLogBufferOffset);
mEarlyLogBufferOffset += HOSTINTF_HEADER_SIZE;
}
if (userData) {
userData->sensType = SENS_TYPE_INVALID;
userData->length = 0;
userData->dataType = HOSTINTF_DATA_TYPE_LOG;
userData->interrupt = NANOHUB_INT_NONWAKEUP;
}
return userData;
#else
return NULL;
#endif
}
#if defined(DEBUG_LOG_EVT)
static void platEarlyLogFree(void *buf)
{
struct HostIntfDataBuffer *userData = (struct HostIntfDataBuffer *)buf;
mEarlyLogBufferCnt += userData->length + HOSTINTF_HEADER_SIZE;
if (mEarlyLogBufferCnt >= mEarlyLogBufferOffset) {
heapFree(mEarlyLogBuffer);
}
}
#endif
void platEarlyLogFlush(void)
{
#if defined(DEBUG_LOG_EVT)
uint16_t i = 0;
struct HostIntfDataBuffer *userData;
mLateBoot = true;
while (i < mEarlyLogBufferOffset) {
userData = (struct HostIntfDataBuffer *)(mEarlyLogBuffer + i);
osEnqueueEvt(EVENT_TYPE_BIT_DISCARDABLE | EVT_DEBUG_LOG, userData, platEarlyLogFree);
i += HOSTINTF_HEADER_SIZE + userData->length;
}
#endif
}
void platLogFlush(void *userData)
{
#ifdef DEBUG_UART_UNITNO
usartFlush(&mDbgUart);
#endif
#if defined(DEBUG_LOG_EVT)
if (userData && mLateBoot)
osEnqueueEvtOrFree(EVENT_TYPE_BIT_DISCARDABLE | EVT_DEBUG_LOG, userData, heapFree);
#endif
}
bool platLogPutcharF(void *userData, char ch)
{
#if defined(DEBUG) && defined(DEBUG_UART_PIN)
if (ch == '\n')
gpioBitbangedUartOut('\r');
gpioBitbangedUartOut(ch);
#endif
#if defined(DEBUG_UART_UNITNO)
if (ch == '\n')
usartPutchar(&mDbgUart, '\r');
usartPutchar(&mDbgUart, ch);
#endif
#if defined(DEBUG_LOG_EVT)
struct HostIntfDataBuffer *buffer;
if (userData) {
buffer = userData;
size_t maxSize = sizeof(buffer->buffer);
// if doing early logging, and early log buffer is full, ignore the rest of early output
if (!mLateBoot && mEarlyLogBufferOffset >= EARLY_LOG_BUF_SIZE && buffer->length < maxSize)
maxSize = buffer->length;
if (buffer->length < maxSize) {
buffer->buffer[buffer->length++] = ch;
if (!mLateBoot)
mEarlyLogBufferOffset++;
} else {
buffer->buffer[maxSize - 1] = '\n';
return false;
}
}
#endif
return true;
}
void platInitialize(void)
{
const uint32_t debugStateInSleepMode = DBG_SLEEP | DBG_STOP | DBG_STANDBY;
uint32_t i;
pwrSystemInit();
//prepare for sleep mode(s)
SCB->SCR &=~ SCB_SCR_SLEEPONEXIT_Msk;
//set ints up for a sane state
//3 bits preemptPriority, 1 bit subPriority
NVIC_SetPriorityGrouping(4);
for (i = 0; i < NUM_INTERRUPTS; i++) {
NVIC_SetPriority(i, NVIC_EncodePriority(4, 2, 1));
NVIC_DisableIRQ(i);
NVIC_ClearPendingIRQ(i);
}
/* disable pins */
for (i = 0; i < 16; i++) {
#if defined(DEBUG) && defined(DEBUG_SWD)
/* pins PA13 and PA14 are used for SWD */
if ((i != 13) && (i != 14))
gpioConfigAnalog(gpioRequest(GPIO_PA(i)));
#else
gpioConfigAnalog(gpioRequest(GPIO_PA(i)));
#endif
gpioConfigAnalog(gpioRequest(GPIO_PB(i)));
gpioConfigAnalog(gpioRequest(GPIO_PC(i)));
gpioConfigAnalog(gpioRequest(GPIO_PD(i)));
gpioConfigAnalog(gpioRequest(GPIO_PE(i)));
gpioConfigAnalog(gpioRequest(GPIO_PH(i)));
}
#ifdef DEBUG_UART_UNITNO
/* Open mDbgUart on PA2 and PA3 */
usartOpen(&mDbgUart, DEBUG_UART_UNITNO, DEBUG_UART_GPIO_TX, DEBUG_UART_GPIO_RX,
115200, USART_DATA_BITS_8,
USART_STOP_BITS_1_0, USART_PARITY_NONE,
USART_FLOW_CONTROL_NONE);
#endif
/* set up debugging */
#if defined(DEBUG) && defined(DEBUG_SWD)
DBGMCU->CR |= debugStateInSleepMode;
#else
DBGMCU->CR &=~ debugStateInSleepMode;
#endif
/* enable MPU */
mpuStart();
/* set up timer used for alarms */
pwrUnitClock(PERIPH_BUS_APB1, PERIPH_APB1_TIM2, true);
TIM2->CR1 = (TIM2->CR1 &~ 0x03E1) | 0x0010; //count down mode with no clock division, disabled
TIM2->PSC = 15; // prescale by 16, so that at 16MHz CPU clock, we get 1MHz timer
TIM2->DIER |= 1; // interrupt when updated (underflowed)
TIM2->ARR = 0xffffffff;
TIM2->EGR = TIM_EGR_UG; // force a reload of the prescaler
NVIC_EnableIRQ(TIM2_IRQn);
rtcInit();
/* bring up systick */
SysTick->CTRL = 0;
SysTick->LOAD = 0x00FFFFFF;
SysTick->VAL = 0;
SysTick->CTRL = SysTick_CTRL_CLKSOURCE_Msk | SysTick_CTRL_TICKINT_Msk | SysTick_CTRL_ENABLE_Msk;
#ifdef DEBUG_LOG_EVT
/* allocate buffer for early boot log message*/
mEarlyLogBuffer = heapAlloc(EARLY_LOG_BUF_SIZE);
#endif
}
static uint64_t platsystickTicksToNs(uint32_t systickTicks)
{
return (uint64_t)systickTicks * 125 / 2;
}
uint64_t platGetTicks(void)
{
uint64_t ret;
uint32_t val;
do {
mem_reorder_barrier(); //mTimeAccumulated may change since it was read in condition check
ret = mTimeAccumulated;
val = SysTick->VAL;
mem_reorder_barrier(); //mTimeAccumulated may change since it was read above
} while (mTimeAccumulated != ret || SysTick->VAL > val);
return platsystickTicksToNs(0x01000000 - val) + ret;
}
/* Timer interrupt handler */
void TIM2_IRQHandler(void);
void TIM2_IRQHandler(void)
{
struct StmTim *tim = (struct StmTim*)TIM2_BASE;
/* int clear */
tim->SR &=~ 1;
/* timer off */
tim->CR1 &=~ 1;
/* call timer handler since it might need to reschedule an interrupt (eg: in case where initial delay was too far off & we were limited by timer length) */
timIntHandler();
}
/* SysTick interrupt handler */
void SysTick_Handler(void);
void SysTick_Handler(void)
{
mTimeAccumulated += platsystickTicksToNs(SysTick->LOAD + 1); //todo - incremenet by actual elapsed nanoseconds and not just "1"
}
bool platRequestDevInSleepMode(uint32_t sleepDevID, uint32_t maxWakeupTime)
{
if (sleepDevID >= PLAT_MAX_SLEEP_DEVS || sleepDevID >= Stm32sleepDevNum)
return false;
mDevsMaxWakeTime[sleepDevID] = maxWakeupTime;
while (!atomicCmpXchg32bits(&mSleepDevsToKeepAlive, mSleepDevsToKeepAlive, mSleepDevsToKeepAlive | (1UL << sleepDevID)));
return true;
}
bool platAdjustDevInSleepMode(uint32_t sleepDevID, uint32_t maxWakeupTime)
{
if (sleepDevID >= PLAT_MAX_SLEEP_DEVS || sleepDevID >= Stm32sleepDevNum)
return false;
mDevsMaxWakeTime[sleepDevID] = maxWakeupTime;
return true;
}
bool platReleaseDevInSleepMode(uint32_t sleepDevID)
{
if (sleepDevID >= PLAT_MAX_SLEEP_DEVS || sleepDevID >= Stm32sleepDevNum)
return false;
while (!atomicCmpXchg32bits(&mSleepDevsToKeepAlive, mSleepDevsToKeepAlive, mSleepDevsToKeepAlive &~ (1UL << sleepDevID)));
return true;
}
static uint64_t platSetTimerAlarm(uint64_t delay) //delay at most that many nsec
{
struct StmTim *tim = (struct StmTim*)TIM2_BASE;
uint32_t delayInUsecs;
//turn off timer to prevent interrupts now
tim->CR1 &=~ 1;
if (delay >= (1000ULL << 32)) //it is only a 32-bit counter - we cannot set delays bigger than that
delayInUsecs = 0xffffffff;
else
delayInUsecs = cpuMathUint44Div1000ToUint32(delay);
tim->CNT = delayInUsecs;
tim->SR &=~ 1; //clear int
tim->CR1 |= 1;
return delayInUsecs;
}
bool platSleepClockRequest(uint64_t wakeupTime, uint32_t maxJitterPpm, uint32_t maxDriftPpm, uint32_t maxErrTotalPpm)
{
uint64_t intState, curTime = timGetTime();
if (wakeupTime && curTime >= wakeupTime)
return false;
intState = cpuIntsOff();
mMaxJitterPpm = maxJitterPpm;
mMaxDriftPpm = maxDriftPpm;
mMaxErrTotalPpm = maxErrTotalPpm;
mWakeupTime = wakeupTime;
//TODO: set an actual alarm here so that if we keep running and do not sleep till this is due, we still fire an interrupt for it!
if (wakeupTime)
platSetTimerAlarm(wakeupTime - curTime);
cpuIntsRestore(intState);
return true;
}
#if !(defined(STM32F4xx_DISABLE_LPLV_SLEEP) && defined(STM32F4xx_DISABLE_LPFD_SLEEP) \
&& defined(STM32F4xx_DISABLE_MRFPD_SLEEP) && defined(STM32F4xx_DISABLE_MR_SLEEP))
static bool sleepClockRtcPrepare(uint64_t delay, uint32_t acceptableJitter, uint32_t acceptableDrift, uint32_t maxAcceptableError, void *userData, uint64_t *savedData)
{
pwrSetSleepType((uint32_t)userData);
*savedData = rtcGetTime();
if (delay && rtcSetWakeupTimer(delay) < 0)
return false;
//sleep with systick off (for timing) and interrupts off (for power due to HWR errata)
SysTick->CTRL &= ~(SysTick_CTRL_TICKINT_Msk | SysTick_CTRL_ENABLE_Msk);
return true;
}
static void sleepClockRtcWake(void *userData, uint64_t *savedData)
{
//re-enable Systic and its interrupt
SysTick->CTRL |= SysTick_CTRL_TICKINT_Msk | SysTick_CTRL_ENABLE_Msk;
mTimeAccumulated += rtcGetTime() - *savedData;
}
#endif
static bool sleepClockTmrPrepare(uint64_t delay, uint32_t acceptableJitter, uint32_t acceptableDrift, uint32_t maxAcceptableError, void *userData, uint64_t *savedData)
{
pwrSetSleepType(stm32f411SleepModeSleep);
platRequestDevInSleepMode(Stm32sleepDevTim2, 0);
*savedData = platSetTimerAlarm(delay ?: ~0ull);
//sleep with systick off (for timing) and interrupts off (for power due to HWR errata)
SysTick->CTRL &= ~(SysTick_CTRL_TICKINT_Msk | SysTick_CTRL_ENABLE_Msk);
return true;
}
static void sleepClockTmrWake(void *userData, uint64_t *savedData)
{
struct StmTim *tim = (struct StmTim*)TIM2_BASE;
uint32_t cnt;
uint16_t sr;
uint64_t leftTicks;
//re-enable Systic and its interrupt
SysTick->CTRL |= SysTick_CTRL_TICKINT_Msk | SysTick_CTRL_ENABLE_Msk;
//stop the timer counting;
tim->CR1 &=~ 1;
//If we are within one time tick of overflow, it is possible for SR to
//not indicate a pending overflow, but CNT contain 0xFFFFFFFF or vice versa,
//depending on the read order of SR and CNT
//read both values until they are stable
do {
sr = tim->SR;
cnt = tim->CNT;
} while (sr != tim->SR || cnt != tim->CNT);
leftTicks = cnt; //if we wake NOT from timer, only count the ticks that actually ticked as "time passed"
if (sr & 1) //if there was an overflow, account for it
leftTicks -= 0x100000000ull;
mTimeAccumulated += (*savedData - leftTicks) * 1000; //this clock runs at 1MHz
platReleaseDevInSleepMode(Stm32sleepDevTim2);
}
static bool sleepClockJustWfiPrepare(uint64_t delay, uint32_t acceptableJitter, uint32_t acceptableDrift, uint32_t maxAcceptableError, void *userData, uint64_t *savedData)
{
pwrSetSleepType(stm32f411SleepModeSleep);
return true;
}
struct PlatSleepAndClockInfo {
uint64_t resolution;
uint64_t resolutionReciprocal; // speed up runtime by using 48 more code bytes? yes please!
uint32_t maxCounter;
uint32_t jitterPpm;
uint32_t driftPpm;
uint32_t maxWakeupTime;
uint32_t devsAvail; //what is available in sleep mode?
bool (*prepare)(uint64_t delay, uint32_t acceptableJitter, uint32_t acceptableDrift, uint32_t maxAcceptableError, void *userData, uint64_t *savedData);
void (*wake)(void *userData, uint64_t *savedData);
void *userData;
} static const platSleepClocks[] = {
#ifndef STM32F4xx_DISABLE_LPLV_SLEEP
{ /* RTC + LPLV STOP MODE */
.resolution = 1000000000ull/32768,
.resolutionReciprocal = U64_RECIPROCAL_CALCULATE(1000000000ull/32768),
.maxCounter = 0xffffffff,
.jitterPpm = 0,
.driftPpm = 50,
.maxWakeupTime = 407000ull,
.devsAvail = (1 << Stm32sleepDevExti),
.prepare = sleepClockRtcPrepare,
.wake = sleepClockRtcWake,
.userData = (void*)stm32f411SleepModeStopLPLV,
},
#endif
#ifndef STM32F4xx_DISABLE_LPFD_SLEEP
{ /* RTC + LPFD STOP MODE */
.resolution = 1000000000ull/32768,
.resolutionReciprocal = U64_RECIPROCAL_CALCULATE(1000000000ull/32768),
.maxCounter = 0xffffffff,
.jitterPpm = 0,
.driftPpm = 50,
.maxWakeupTime = 130000ull,
.devsAvail = (1 << Stm32sleepDevExti),
.prepare = sleepClockRtcPrepare,
.wake = sleepClockRtcWake,
.userData = (void*)stm32f411SleepModeStopLPFD,
},
#endif
#ifndef STM32F4xx_DISABLE_MRFPD_SLEEP
{ /* RTC + MRFPD STOP MODE */
.resolution = 1000000000ull/32768,
.resolutionReciprocal = U64_RECIPROCAL_CALCULATE(1000000000ull/32768),
.maxCounter = 0xffffffff,
.jitterPpm = 0,
.driftPpm = 50,
.maxWakeupTime = 111000ull,
.devsAvail = (1 << Stm32sleepDevExti),
.prepare = sleepClockRtcPrepare,
.wake = sleepClockRtcWake,
.userData = (void*)stm32f411SleepModeStopMRFPD,
},
#endif
#ifndef STM32F4xx_DISABLE_MR_SLEEP
{ /* RTC + MR STOP MODE */
.resolution = 1000000000ull/32768,
.resolutionReciprocal = U64_RECIPROCAL_CALCULATE(1000000000ull/32768),
.maxCounter = 0xffffffff,
.jitterPpm = 0,
.driftPpm = 50,
.maxWakeupTime = 14500ull,
.devsAvail = (1 << Stm32sleepDevExti),
.prepare = sleepClockRtcPrepare,
.wake = sleepClockRtcWake,
.userData = (void*)stm32f411SleepModeStopMR,
},
#endif
#ifndef STM32F4xx_DISABLE_TIM2_SLEEP
{ /* TIM2 + SLEEP MODE */
.resolution = 1000000000ull/1000000,
.resolutionReciprocal = U64_RECIPROCAL_CALCULATE(1000000000ull/1000000),
.maxCounter = 0xffffffff,
.jitterPpm = 0,
.driftPpm = 30,
.maxWakeupTime = 12ull,
.devsAvail = (1 << Stm32sleepDevTim2) | (1 << Stm32sleepDevTim4) | (1 << Stm32sleepDevTim5) | (1 << Stm32sleepDevTim9) | (1 << Stm32sleepWakeup) | (1 << Stm32sleepDevSpi2) | (1 << Stm32sleepDevSpi3) | (1 << Stm32sleepDevI2c1) | (1 << Stm32sleepDevI2c2) | (1 << Stm32sleepDevI2c3) | (1 << Stm32sleepDevExti),
.prepare = sleepClockTmrPrepare,
.wake = sleepClockTmrWake,
},
#endif
{ /* just WFI */
.resolution = 16000000000ull/1000000,
.resolutionReciprocal = U64_RECIPROCAL_CALCULATE(16000000000ull/1000000),
.maxCounter = 0xffffffff,
.jitterPpm = 0,
.driftPpm = 0,
.maxWakeupTime = 0,
.devsAvail = (1 << Stm32sleepDevTim2) | (1 << Stm32sleepDevTim4) | (1 << Stm32sleepDevTim5) | (1 << Stm32sleepDevTim9) | (1 << Stm32sleepWakeup) | (1 << Stm32sleepDevSpi2) | (1 << Stm32sleepDevSpi3) | (1 << Stm32sleepDevI2c1) | (1 << Stm32sleepDevI2c2) | (1 << Stm32sleepDevI2c3) | (1 << Stm32sleepDevExti),
.prepare = sleepClockJustWfiPrepare,
},
/* terminator */
{0},
};
void platSleep(void)
{
uint64_t predecrement = 0, curTime = timGetTime(), length = mWakeupTime - curTime, intState;
const struct PlatSleepAndClockInfo *sleepClock, *leastBadOption = NULL;
uint64_t savedData;
uint32_t i;
//shortcut the sleep if it is time to wake up already
if (mWakeupTime && mWakeupTime < curTime)
return;
for (sleepClock = platSleepClocks; sleepClock->maxCounter; sleepClock++) {
bool potentialLeastBadOption = false;
//if we have timers, consider them
if (mWakeupTime) {
//calculate how much we WOULD predecerement by
predecrement = sleepClock->resolution + sleepClock->maxWakeupTime;
//skip options with too much jitter (after accounting for error
if (sleepClock->jitterPpm > mMaxJitterPpm)
continue;
//skip options that will take too long to wake up to be of use
if (predecrement > length)
continue;
//skip options with too much drift
if (sleepClock->driftPpm > mMaxDriftPpm)
continue;
//skip options that do not let us sleep enough, but save them for later if we simply must pick something
if (cpuMathRecipAssistedUdiv64by64(length, sleepClock->resolution, sleepClock->resolutionReciprocal) > sleepClock->maxCounter && !leastBadOption)
potentialLeastBadOption = true;
}
//skip all options that do not keep enough deviceas awake
if ((sleepClock->devsAvail & mSleepDevsToKeepAlive) != mSleepDevsToKeepAlive)
continue;
//skip all options that wake up too slowly
for (i = 0; i < Stm32sleepDevNum; i++) {
if (!(mSleepDevsToKeepAlive & (1 << i)))
continue;
if (mDevsMaxWakeTime[i] < sleepClock->maxWakeupTime)
break;
}
if (i != Stm32sleepDevNum)
continue;
//if it will not let us sleep long enough save it as a possibility and go on
if (potentialLeastBadOption && !leastBadOption)
leastBadOption = sleepClock;
else //if it fits us perfectly, pick it
break;
}
if (!sleepClock->maxCounter)
sleepClock = leastBadOption;
if (!sleepClock) {
//should never happen - this will spin the CPU and be bad, but it WILL work in all cases
return;
}
//turn ints off in prep for sleep
wdtDisableClk();
intState = cpuIntsOff();
//options? config it
if (sleepClock->prepare &&
sleepClock->prepare(mWakeupTime ? length - sleepClock->maxWakeupTime : 0,
mMaxJitterPpm, mMaxDriftPpm, mMaxErrTotalPpm,
sleepClock->userData, &savedData)) {
asm volatile ("wfi\n"
"nop" :::"memory");
//wakeup
if (sleepClock->wake)
sleepClock->wake(sleepClock->userData, &savedData);
}
//re-enable interrupts and let the handlers run
cpuIntsRestore(intState);
wdtEnableClk();
}
void* platGetPersistentRamStore(uint32_t *bytes)
{
*bytes = sizeof(uint32_t[RTC_NUM_BACKUP_REGS]);
return rtcGetBackupStorage();
}
uint32_t platFreeResources(uint32_t tid)
{
uint32_t dmaCount = dmaStopAll(tid);
uint32_t irqCount = extiUnchainAll(tid);
return (dmaCount << 8) | irqCount;
}
void platPeriodic()
{
wdtPing();
}