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Split fxns for configuring EIC and WDT clocks
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Signed-off-by: Sara Damiano <[email protected]>
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@SRGDamia1
SRGDamia1 committed Oct 22, 2024
1 parent f5947fc commit f3527f2
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Showing 3 changed files with 159 additions and 74 deletions.
54 changes: 24 additions & 30 deletions src/LoggerBase.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -568,30 +568,6 @@ void Logger::systemSleep(void) {
pinMode(_mcuWakePin, _wakePinMode);
// attach the interrupt
enableInterrupt(_mcuWakePin, wakeISR, RISING);

// #if defined(ARDUINO_ARCH_SAMD) && !defined(__SAMD51__)
// // Reconfigure the external interrupt controller (EIC) clock after
// attaching
// // the interrupt. This is needed because the __initialize function called
// // the first time the attachInterrupt function is run will reconfigure
// the
// // clock source for the EIC to GCLK0 every time a new interrupt is
// attached
// // - and after being detached, reattaching the same interrupt is just
// like a
// // new one). We need to switch the EIC source back to our configured
// GCLK2. MS_DEEP_DBG(F("Re-configuring WDT and EIC clock"));
// watchDogTimer.configureWDTClockSource();

// // get the interrupt number associated with the pin
// // From ArduinoLowPower.cpp
// EExt_Interrupts in = g_APinDescription[_mcuWakePin].ulExtInt;
// // Make sure the wakeup capability is enabled on the pin
// // From ArduinoLowPower.cpp
// EIC->WAKEUP.reg |= (1 << in);
// // enable the voltage regulator in standby mode
// SYSCTRL->VREG.bit.RUNSTDBY = 1;
// #endif // #if defined(ARDUINO_ARCH_SAMD) && ! defined(__SAMD51__)
#endif //#if !defined(MS_USE_RTC_ZERO)


Expand Down Expand Up @@ -1275,23 +1251,41 @@ void Logger::begin() {
USB->DEVICE.CTRLA.bit.ENABLE = 1; // Enable the USB peripheral
while (USB->DEVICE.SYNCBUSY.bit.ENABLE)
; // Wait for synchronization
#if !defined(__SAMD51__)
// Keep the voltage regulator running in standby
// SYSCTRL->VREG.bit.RUNSTDBY = 1;
#endif
#endif

MS_DBG(F("Setting up a watch-dog timer to fire after 15 minutes of "
"inactivity"));
watchDogTimer.setupWatchDog((uint32_t)(5 * 60 * 3));
// Enable the watchdog
watchDogTimer.enableWatchDog();

#if defined(ARDUINO_ARCH_SAMD)
MS_DEEP_DBG(
F("Attaching an empty interrupt to force interrupt configuration"));
if (_mcuWakePin >= 0) {
attachInterrupt(_mcuWakePin, nullptr, CHANGE);
detachInterrupt(_mcuWakePin);
} else if (_buttonPin >= 0) {
attachInterrupt(_buttonPin, nullptr, CHANGE);
detachInterrupt(_buttonPin);
} else {
// if we don't know of a pin we can
attachInterrupt(1, nullptr, CHANGE);
detachInterrupt(1);
}
// NOTE: This has to be done AFTER setupWatchDog, because setupWatchDog
// calls config32kOSC() and configureClockGenerator(), both of which are
// needed before we can call configureEICClock(). This also should happen
// after the fake interrupt is set to force a call to __initialize() in
// WInterrupts.c
MS_DEEP_DBG(F("Configuring the EIC clock"));
watchDogTimer.configureEICClock();
#endif

MS_DBG(F("Setting up a watch-dog timer to fire after 15 minutes of "
"inactivity"));
watchDogTimer.setupWatchDog((uint32_t)(5 * 60 * 3));
// Enable the watchdog
watchDogTimer.enableWatchDog();

// Set the pins for I2C
MS_DBG(F("Setting I2C Pins to INPUT_PULLUP"));
#ifdef SDA
Expand Down
164 changes: 122 additions & 42 deletions src/WatchDogs/WatchDogSAMD.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -43,7 +43,8 @@ void extendedWatchDogSAMD::setupWatchDog(uint32_t resetTime_s) {
waitForWDTBitSync();

config32kOSC();
configureWDTClockSource();
configureClockGenerator();
configureWDTClock();

// Enable WDT early-warning interrupt
NVIC_DisableIRQ(WDT_IRQn);
Expand Down Expand Up @@ -97,7 +98,7 @@ void extendedWatchDogSAMD::enableWatchDog() {
// Set the enable bit
#if defined(__SAMD51__)
WDT->CTRLA.bit.ENABLE = 1;
#else
#else // SAMD21
WDT->CTRL.bit.ENABLE = 1;
#endif
waitForWDTBitSync();
Expand All @@ -107,7 +108,7 @@ void extendedWatchDogSAMD::enableWatchDog() {
void extendedWatchDogSAMD::disableWatchDog() {
#if defined(__SAMD51__)
WDT->CTRLA.bit.ENABLE = 0;
#else
#else // SAMD21
WDT->CTRL.bit.ENABLE = 0;
#endif
waitForWDTBitSync();
Expand All @@ -128,7 +129,7 @@ void extendedWatchDogSAMD::resetWatchDog() {

void extendedWatchDogSAMD::config32kOSC() {
#if defined(__SAMD51__)
// SAMD51 WDT uses OSCULP32k as input clock now
// SAMD51 WDT uses OSCULP32k as input clock, make sure it's enabled
// section: 20.5.3
MS_DEEP_DBG(F("Configuring the output of the ultra-low power internal 32k "
"oscillator for the watchdog."));
Expand All @@ -145,65 +146,144 @@ void extendedWatchDogSAMD::config32kOSC() {
#endif
}

void extendedWatchDogSAMD::configureWDTClockSource() {
#if !defined(__SAMD51__)
// Configure the generic clock generator divisor for the clock generator
// The divisor register must be configured before generator control register
// divisor = 32 (2^(DIV+1)) = 4
void extendedWatchDogSAMD::configureClockGenerator() {
#if defined(__SAMD51__)
// Do nothing
// The SAMD51 WDT always uses OSCULP32k directly; no separate clock
// generator is needed as long as OSCULP32k is enabled.
// The SAMD51 can also use OSCULP32k directly for the EIC.
#else // SAMD21
// Per datasheet 15.6.2.6, the source for the generic clock generator can be
// changed on the fly, so we don't need to disable it for configuration.

// Configure the generic clock generator **divisor** for the clock
// generator.
// The divisor determines the relationship between the generic clock's tick
// speed and the clock source's tick speed.
// The divisor register must be configured before the generator control
// register.
// divisor = 32(2 ^ (DIV + 1)) = 4
// With 32 divisor the actual clock speed is ~1024Hz clock.
MS_DEEP_DBG(F("Configuring the divisor for generic clock generator"),
GENERIC_CLOCK_GENERATOR_MS);
GCLK->GENDIV.reg =
GCLK_GENDIV_ID(
GENERIC_CLOCK_GENERATOR_MS) | // Select Generic Clock Generator
GCLK_GENDIV_DIV(4); // Divide the clock source by 32
waitForGCLKBitSync();

// Configure the generic clock **generator**
// Use the built-in ultra-low power internal 32.768kHz oscillator for the
// watchdog and the external interrupt controller. This is less accurate
// than the 32k crystal, but uses less power. For the watchdog and the
// external interrupts, we don't need very high accuracy, so lower power is
// better.

// source GCLK from the external oscillator
MS_DEEP_DBG(F("Setting the ultra-low power internal 32k oscillator as the "
"clock source for generic clock generator"),
// NOTE: The generic clock generator must be enabled by performing a single
// 32-bit write to the Generic Clock Generator Control register (GENCTRL) -
// ie, do this all in one step
MS_DEEP_DBG(F("Configuring generic clock generator"),
GENERIC_CLOCK_GENERATOR_MS);
GCLK->GENCTRL.reg =
GCLK->GENCTRL.reg = static_cast<uint32_t>(
GCLK_GENCTRL_ID(GENERIC_CLOCK_GENERATOR_MS) | // Select GCLK
GCLK_GENCTRL_GENEN | // Enable the generic clock clontrol
GCLK_GENCTRL_SRC_OSCULP32K | // Select the built-in ultra-low power
// internal oscillator
GCLK_GENCTRL_RUNSTDBY | // DO run in standby
GCLK_GENCTRL_DIVSEL; // Select to divide clock by
// the prescaler above
GCLK_GENCTRL_DIVSEL); // Select to divide clock by 2^(GENDIV.DIV+1).
waitForGCLKBitSync();
#endif
}

// Feed configured GCLK to WDT (Watchdog Timer) **AND** the EIC (external
// interrupt controller)
// NOTE: This must be done in two steps, only one clock control id can be
// set at one time! See
void extendedWatchDogSAMD::configureWDTClock() {
#if defined(__SAMD51__)
// Do nothing
#else // SAMD21
// Per datasheet 16.6.3.3 the generic clock must be disabled before being
// re-enabled with a new clock source setting.
MS_DEEP_DBG(F("Disabling WDT peripeheral clock for configuration"));
GCLK->CLKCTRL.bit.ID = GCM_WDT; // select the WDT's clock
GCLK->CLKCTRL.bit.CLKEN = 0; // Disable the clock
waitForGCLKBitSync();

// Feed configured GCLK to WDT (Watchdog Timer)
// NOTE: Only one clock control id can be set at one time! See
// https://stackoverflow.com/questions/70303177/atsamd-gclkx-for-more-peripherals
MS_DEEP_DBG(F("Feeding configured GCLK"), GENERIC_CLOCK_GENERATOR_MS,
F("to WDT"));
GCLK->CLKCTRL.reg =
(uint16_t)(GCLK_CLKCTRL_GEN(
GENERIC_CLOCK_GENERATOR_MS) | // Select generic clock
// generator
GCLK_CLKCTRL_CLKEN | // Enable the generic clock clontrol
GCLK_CLKCTRL_ID(GCM_WDT)); // Feed the GCLK to the WDT
MS_DEEP_DBG(F("Configuring and enabling peripheral clock for WDT"));
GCLK->CLKCTRL.reg = static_cast<uint16_t>(
GCLK_CLKCTRL_GEN(GENERIC_CLOCK_GENERATOR_MS) | // Select generic clock
// generator
GCLK_CLKCTRL_CLKEN | // Enable the generic clock clontrol
GCLK_CLKCTRL_ID(GCM_WDT)); // Feed the GCLK to the WDT
waitForGCLKBitSync();
#endif
}

void extendedWatchDogSAMD::configureEICClock() {
#if defined(__SAMD51__)
// Enable the power management mask for the EIC clock
// NOTE: this is the default setting at power on and is not changed by the
// Arduino core.
MCLK->APBAMASK.reg |= PM_APBAMASK_EIC;

// Enable EIC interrupts (copied and repeated from WInterrutps.c)
for (uint32_t i = 0; i <= 15; i++) // EIC_0_IRQn = 12 ... EIC_15_IRQn = 27
{
uint8_t irqn = EIC_0_IRQn + i;
NVIC_DisableIRQ(irqn);
NVIC_ClearPendingIRQ(irqn);
NVIC_SetPriority(irqn, 0);
NVIC_EnableIRQ(irqn);
}

MS_DEEP_DBG(F("Disabling EIC controller configuration"));
EIC->CTRLA.bit.ENABLE = 0;
while (EIC->SYNCBUSY.bit.ENABLE == 1) {}

MS_DEEP_DBG(F("Selecting the ULP32K clock as the source for the EIC"));
// NOTE: this is the default
// The EIC can be clocked either by GCLK_EIC (when a frequency higher
// than 32.768 KHz is required for filtering) or by CLK_ULP32K (when power
// consumption is the priority).
// Since we're interested in power consumption, stick to the CLK_ULP32K.
// Using the ULP32K also saves us the trouble of configuring a generic clock
// for the EIC. This bit is not Write-Synchronized.
EIC->CTRLA.bit.CKSEL = 1; // 0 for GCLK_EIC, 1 for CLK_ULP32K

MS_DEEP_DBG(F("Re-enabling the EIC"));
EIC->CTRLA.bit.ENABLE = 1;
while (EIC->SYNCBUSY.bit.ENABLE == 1) {}
#else // SAMD21
// Enable the power management mask for the EIC clock
// NOTE: this is the default setting at power on and is not changed by the
// Arduino core.
PM->APBAMASK.reg |= PM_APBAMASK_EIC;

// Enable EIC interrupts (copied and repeated from WInterrutps.c)
NVIC_DisableIRQ(EIC_IRQn);
NVIC_ClearPendingIRQ(EIC_IRQn);
NVIC_SetPriority(EIC_IRQn, 0);
NVIC_EnableIRQ(EIC_IRQn);

// Per datasheet 16.6.3.3 the generic clock must be disabled before being
// re-enabled with a new clock source setting.
MS_DEEP_DBG(F("Disabling EIC peripeheral clock for configuration"));
GCLK->CLKCTRL.bit.ID = GCM_EIC; // select the WDT's clock
GCLK->CLKCTRL.bit.CLKEN = 0; // Disable the clock
waitForGCLKBitSync();
MS_DEEP_DBG(F("Feeding configured GCLK"), GENERIC_CLOCK_GENERATOR_MS,
F("to EIC"));
GCLK->CLKCTRL.reg =
(uint16_t)(GCLK_CLKCTRL_GEN(
GENERIC_CLOCK_GENERATOR_MS) | // Select generic clock
// generator
GCLK_CLKCTRL_CLKEN | // Enable the generic clock clontrol
GCLK_CLKCTRL_ID(GCM_EIC)); // Feed the GCLK to the EIC

// Feed configured GCLK to EIC (external interrupt controller)
// NOTE: Only one clock control id can be set at one time! See
// https://stackoverflow.com/questions/70303177/atsamd-gclkx-for-more-peripherals
MS_DEEP_DBG(F("Configuring and enabling peripheral clock for EIC"));
GCLK->CLKCTRL.reg = static_cast<uint16_t>(
GCLK_CLKCTRL_GEN(GENERIC_CLOCK_GENERATOR_MS) | // Select generic clock
// generator
GCLK_CLKCTRL_CLKEN | // Enable the generic clock clontrol
GCLK_CLKCTRL_ID(GCM_EIC)); // Feed the GCLK to the EIC
waitForGCLKBitSync();

// Enable EIC after configuring its clock
// Re-enable EIC after configuring its clock
EIC->CTRL.bit.ENABLE = 1;
while (EIC->STATUS.bit.SYNCBUSY == 1) {}

#endif
}

Expand All @@ -212,7 +292,7 @@ void extendedWatchDogSAMD::waitForWDTBitSync() {
while (WDT->SYNCBUSY.reg) {
// Wait for synchronization
}
#else
#else // SAMD21
while (WDT->STATUS.bit.SYNCBUSY) {
// Wait for synchronization
}
Expand All @@ -224,7 +304,7 @@ void extendedWatchDogSAMD::waitForGCLKBitSync() {
while (GCLK->SYNCBUSY.reg &
GCLK_SYNCBUSY_GENCTRL(GENERIC_CLOCK_GENERATOR_MS))
; // Wait for the clock generator sync busy bit to clear
#else
#else // SAMD21
while (GCLK->STATUS.bit.SYNCBUSY)
; // Wait for synchronization
#endif
Expand Down Expand Up @@ -252,7 +332,7 @@ void WDT_Handler(void) {
while (WDT->SYNCBUSY.reg) {
// wait
}
#else
#else // SAMD21
while (WDT->STATUS.bit.SYNCBUSY) {
// wait
}
Expand Down
15 changes: 13 additions & 2 deletions src/WatchDogs/WatchDogSAMD.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -89,9 +89,20 @@ class extendedWatchDogSAMD {
*/
void config32kOSC();
/**
* @brief Attach peripheral clock to 32k oscillator
* @brief Configure the generic clock generator - sourced from the 32k
* oscillator
*/
void configureWDTClockSource();
void configureClockGenerator();
/**
* @brief Configure the peripheral clock for the WDT sourced from the
* generic clock generator
*/
void configureWDTClock();
/**
* @brief Configure the peripheral clock for the external interrupt
* congtroller (EIC) - sourced from the generic clock generator
*/
void configureEICClock();


/**
Expand Down

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