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micropython/ports/stm32/powerctrl.c

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/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2013-2018 Damien P. George
*
* 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 "py/mperrno.h"
#include "py/mphal.h"
#include "powerctrl.h"
#include "rtc.h"
#include "genhdr/pllfreqtable.h"
#include "extmod/modbluetooth.h"
#if defined(STM32H5) || defined(STM32H7)
#define RCC_SR RSR
#if defined(STM32H747xx)
#define RCC_SR_SFTRSTF RCC_RSR_SFT2RSTF
#else
#define RCC_SR_SFTRSTF RCC_RSR_SFTRSTF
#endif
#define RCC_SR_RMVF RCC_RSR_RMVF
// This macro returns the actual voltage scaling level factoring in the power overdrive bit.
// If the current voltage scale is VOLTAGE_SCALE1 and PWER_ODEN bit is set return VOLTAGE_SCALE0
// otherwise the current voltage scaling (level VOS1 to VOS3) set in PWER_CSR is returned instead.
#if defined(STM32H7A3xx) || defined(STM32H7A3xxQ) || \
defined(STM32H7B3xx) || defined(STM32H7B3xxQ)
// TODO
#define POWERCTRL_GET_VOLTAGE_SCALING() PWR_REGULATOR_VOLTAGE_SCALE0
#elif defined(STM32H723xx)
#define POWERCTRL_GET_VOLTAGE_SCALING() LL_PWR_GetRegulVoltageScaling()
#elif defined(STM32H5)
#define POWERCTRL_GET_VOLTAGE_SCALING() LL_PWR_GetRegulVoltageScaling()
#else
#define POWERCTRL_GET_VOLTAGE_SCALING() \
(((PWR->CSR1 & PWR_CSR1_ACTVOS) && (SYSCFG->PWRCR & SYSCFG_PWRCR_ODEN)) ? \
PWR_REGULATOR_VOLTAGE_SCALE0 : (PWR->CSR1 & PWR_CSR1_ACTVOS))
#endif
#else
#define RCC_SR CSR
#define RCC_SR_SFTRSTF RCC_CSR_SFTRSTF
#define RCC_SR_RMVF RCC_CSR_RMVF
#endif
// Whether this MCU has an independent PLL which can generate 48MHz for USB.
#if defined(STM32F413xx)
// STM32F413 uses PLLI2S as secondary PLL.
#define HAVE_PLL48 1
#define RCC_CR_PLL48_ON RCC_CR_PLLI2SON
#define RCC_CR_PLL48_RDY RCC_CR_PLLI2SRDY
#elif defined(STM32F7)
// STM32F7 uses PLLSAI as secondary PLL.
#define HAVE_PLL48 1
#define RCC_CR_PLL48_ON RCC_CR_PLLSAION
#define RCC_CR_PLL48_RDY RCC_CR_PLLSAIRDY
#else
// MCU does not have a secondary PLL.
#define HAVE_PLL48 0
#endif
#if MICROPY_HW_ENTER_BOOTLOADER_VIA_RESET
// Location in RAM of bootloader state (just after the top of the stack).
// STM32H7 has ECC and writes to RAM must be 64-bit so they are fully committed
// to actual SRAM before a system reset occurs.
#define BL_STATE_PTR ((uint64_t *)&_bl_state)
#define BL_STATE_KEY (0x5a5)
#define BL_STATE_KEY_MASK (0xfff)
#define BL_STATE_KEY_SHIFT (32)
#define BL_STATE_INVALID (0)
#define BL_STATE_VALID(reg, addr) ((uint64_t)(reg) | ((uint64_t)((addr) | BL_STATE_KEY)) << BL_STATE_KEY_SHIFT)
#define BL_STATE_GET_REG(s) ((s) & 0xffffffff)
#define BL_STATE_GET_KEY(s) (((s) >> BL_STATE_KEY_SHIFT) & BL_STATE_KEY_MASK)
#define BL_STATE_GET_ADDR(s) (((s) >> BL_STATE_KEY_SHIFT) & ~BL_STATE_KEY_MASK)
extern uint64_t _bl_state[];
#endif
static inline void powerctrl_disable_hsi_if_unused(void) {
#if !MICROPY_HW_CLK_USE_HSI && (defined(STM32F4) || defined(STM32F7) || defined(STM32H7))
// Disable HSI if it's not used to save a little bit of power
__HAL_RCC_HSI_DISABLE();
#endif
}
NORETURN void powerctrl_mcu_reset(void) {
#if MICROPY_HW_ENTER_BOOTLOADER_VIA_RESET
*BL_STATE_PTR = BL_STATE_INVALID;
#if __DCACHE_PRESENT == 1
SCB_CleanDCache();
#endif
#endif
NVIC_SystemReset();
}
NORETURN static __attribute__((naked)) void branch_to_bootloader(uint32_t r0, uint32_t bl_addr) {
__asm volatile (
"ldr r2, [r1, #0]\n" // get address of stack pointer
"msr msp, r2\n" // get stack pointer
"ldr r2, [r1, #4]\n" // get address of destination
"bx r2\n" // branch to bootloader
);
MP_UNREACHABLE;
}
NORETURN void powerctrl_enter_bootloader(uint32_t r0, uint32_t bl_addr) {
#if MICROPY_HW_ENTER_BOOTLOADER_VIA_RESET
// Enter the bootloader via a reset, so everything is reset (including WDT).
// Upon reset powerctrl_check_enter_bootloader() will jump to the bootloader.
*BL_STATE_PTR = BL_STATE_VALID(r0, bl_addr);
#if __DCACHE_PRESENT == 1
SCB_CleanDCache();
#endif
NVIC_SystemReset();
#else
// Enter the bootloader via a direct jump.
branch_to_bootloader(r0, bl_addr);
#endif
}
void powerctrl_check_enter_bootloader(void) {
#if MICROPY_HW_ENTER_BOOTLOADER_VIA_RESET
uint64_t bl_state = *BL_STATE_PTR;
*BL_STATE_PTR = BL_STATE_INVALID;
if (BL_STATE_GET_KEY(bl_state) == BL_STATE_KEY && (RCC->RCC_SR & RCC_SR_SFTRSTF)) {
// Reset by NVIC_SystemReset with bootloader data set -> branch to bootloader
RCC->RCC_SR = RCC_SR_RMVF;
#if defined(STM32F0) || defined(STM32F4) || defined(STM32G0) || defined(STM32G4) || defined(STM32L0) || defined(STM32L1) || defined(STM32L4) || defined(STM32WB)
__HAL_SYSCFG_REMAPMEMORY_SYSTEMFLASH();
#endif
branch_to_bootloader(BL_STATE_GET_REG(bl_state), BL_STATE_GET_ADDR(bl_state));
}
#endif
}
#if !defined(STM32F0) && !defined(STM32L0) && !defined(STM32WB) && !defined(STM32WL)
typedef struct _sysclk_scaling_table_entry_t {
uint16_t mhz;
uint16_t value;
} sysclk_scaling_table_entry_t;
#if defined(STM32F7)
static const sysclk_scaling_table_entry_t volt_scale_table[] = {
{ 151, PWR_REGULATOR_VOLTAGE_SCALE3 },
{ 180, PWR_REGULATOR_VOLTAGE_SCALE2 },
// Above 180MHz uses default PWR_REGULATOR_VOLTAGE_SCALE1
};
#elif defined(STM32H7A3xx) || defined(STM32H7A3xxQ) || \
defined(STM32H7B3xx) || defined(STM32H7B3xxQ)
static const sysclk_scaling_table_entry_t volt_scale_table[] = {
// See table 15 "FLASH recommended number of wait states and programming delay" of RM0455.
{88, PWR_REGULATOR_VOLTAGE_SCALE3},
{160, PWR_REGULATOR_VOLTAGE_SCALE2},
{225, PWR_REGULATOR_VOLTAGE_SCALE1},
{280, PWR_REGULATOR_VOLTAGE_SCALE0},
};
#elif defined(STM32H7)
static const sysclk_scaling_table_entry_t volt_scale_table[] = {
// See table 55 "Kernel clock distribution overview" of RM0433.
{200, PWR_REGULATOR_VOLTAGE_SCALE3},
{300, PWR_REGULATOR_VOLTAGE_SCALE2},
// Above 300MHz uses default PWR_REGULATOR_VOLTAGE_SCALE1
// (above 400MHz needs special handling for overdrive, currently unsupported)
};
#endif
static int powerctrl_config_vos(uint32_t sysclk_mhz) {
#if defined(STM32F7) || defined(STM32H7)
uint32_t volt_scale = PWR_REGULATOR_VOLTAGE_SCALE1;
for (int i = 0; i < MP_ARRAY_SIZE(volt_scale_table); ++i) {
if (sysclk_mhz <= volt_scale_table[i].mhz) {
volt_scale = volt_scale_table[i].value;
break;
}
}
if (HAL_PWREx_ControlVoltageScaling(volt_scale) != HAL_OK) {
return -MP_EIO;
}
#endif
return 0;
}
// Assumes that PLL is used as the SYSCLK source
int powerctrl_rcc_clock_config_pll(RCC_ClkInitTypeDef *rcc_init, uint32_t sysclk_mhz, bool need_pll48) {
uint32_t flash_latency;
#if HAVE_PLL48
if (need_pll48) {
// Configure secondary PLL at 48MHz for those peripherals that need this freq
// (the calculation assumes it can get an integral value of PLL-N).
#if defined(STM32F413xx)
const uint32_t plli2sm = HSE_VALUE / 1000000;
const uint32_t plli2sq = 2;
const uint32_t plli2sr = 2;
const uint32_t plli2sn = 48 * plli2sq;
RCC->PLLI2SCFGR = plli2sr << RCC_PLLI2SCFGR_PLLI2SR_Pos
| plli2sq << RCC_PLLI2SCFGR_PLLI2SQ_Pos
| plli2sn << RCC_PLLI2SCFGR_PLLI2SN_Pos
| plli2sm << RCC_PLLI2SCFGR_PLLI2SM_Pos;
#else
const uint32_t pllm = (RCC->PLLCFGR >> RCC_PLLCFGR_PLLM_Pos) & 0x3f;
const uint32_t pllsaip = 4;
const uint32_t pllsaiq = 2;
const uint32_t pllsain = 48 * pllsaip * pllm / (HSE_VALUE / 1000000);
RCC->PLLSAICFGR = pllsaiq << RCC_PLLSAICFGR_PLLSAIQ_Pos
| (pllsaip / 2 - 1) << RCC_PLLSAICFGR_PLLSAIP_Pos
| pllsain << RCC_PLLSAICFGR_PLLSAIN_Pos;
#endif
// Turn on the PLL and wait for it to be ready.
RCC->CR |= RCC_CR_PLL48_ON;
uint32_t ticks = mp_hal_ticks_ms();
while (!(RCC->CR & RCC_CR_PLL48_RDY)) {
if (mp_hal_ticks_ms() - ticks > 200) {
return -MP_ETIMEDOUT;
}
}
// Select the alternate 48MHz source.
RCC->DCKCFGR2 |= RCC_DCKCFGR2_CK48MSEL;
}
#endif
// If possible, scale down the internal voltage regulator to save power
int ret = powerctrl_config_vos(sysclk_mhz);
if (ret) {
return ret;
}
#if defined(STM32F7)
// These flash_latency values assume a supply voltage between 2.7V and 3.6V
if (sysclk_mhz <= 30) {
flash_latency = FLASH_LATENCY_0;
} else if (sysclk_mhz <= 60) {
flash_latency = FLASH_LATENCY_1;
} else if (sysclk_mhz <= 90) {
flash_latency = FLASH_LATENCY_2;
} else if (sysclk_mhz <= 120) {
flash_latency = FLASH_LATENCY_3;
} else if (sysclk_mhz <= 150) {
flash_latency = FLASH_LATENCY_4;
} else if (sysclk_mhz <= 180) {
flash_latency = FLASH_LATENCY_5;
} else if (sysclk_mhz <= 210) {
flash_latency = FLASH_LATENCY_6;
} else {
flash_latency = FLASH_LATENCY_7;
}
#elif defined(MICROPY_HW_FLASH_LATENCY)
flash_latency = MICROPY_HW_FLASH_LATENCY;
#else
flash_latency = FLASH_LATENCY_5;
#endif
rcc_init->SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
if (HAL_RCC_ClockConfig(rcc_init, flash_latency) != HAL_OK) {
return -MP_EIO;
}
powerctrl_disable_hsi_if_unused();
return 0;
}
#endif
#if !defined(STM32F0) && !defined(STM32G0) && !defined(STM32L0) && !defined(STM32L1) && !defined(STM32L4)
static uint32_t calc_ahb_div(uint32_t wanted_div) {
#if defined(STM32H7)
if (wanted_div <= 1) {
return RCC_HCLK_DIV1;
} else if (wanted_div <= 2) {
return RCC_HCLK_DIV2;
} else if (wanted_div <= 4) {
return RCC_HCLK_DIV4;
} else if (wanted_div <= 8) {
return RCC_HCLK_DIV8;
} else if (wanted_div <= 16) {
return RCC_HCLK_DIV16;
} else if (wanted_div <= 64) {
return RCC_HCLK_DIV64;
} else if (wanted_div <= 128) {
return RCC_HCLK_DIV128;
} else if (wanted_div <= 256) {
return RCC_HCLK_DIV256;
} else {
return RCC_HCLK_DIV512;
}
#else
if (wanted_div <= 1) {
return RCC_SYSCLK_DIV1;
} else if (wanted_div <= 2) {
return RCC_SYSCLK_DIV2;
} else if (wanted_div <= 4) {
return RCC_SYSCLK_DIV4;
} else if (wanted_div <= 8) {
return RCC_SYSCLK_DIV8;
} else if (wanted_div <= 16) {
return RCC_SYSCLK_DIV16;
} else if (wanted_div <= 64) {
return RCC_SYSCLK_DIV64;
} else if (wanted_div <= 128) {
return RCC_SYSCLK_DIV128;
} else if (wanted_div <= 256) {
return RCC_SYSCLK_DIV256;
} else {
return RCC_SYSCLK_DIV512;
}
#endif
}
static uint32_t calc_apb1_div(uint32_t wanted_div) {
#if defined(STM32H7)
if (wanted_div <= 1) {
return RCC_APB1_DIV1;
} else if (wanted_div <= 2) {
return RCC_APB1_DIV2;
} else if (wanted_div <= 4) {
return RCC_APB1_DIV4;
} else if (wanted_div <= 8) {
return RCC_APB1_DIV8;
} else {
return RCC_APB1_DIV16;
}
#else
if (wanted_div <= 1) {
return RCC_HCLK_DIV1;
} else if (wanted_div <= 2) {
return RCC_HCLK_DIV2;
} else if (wanted_div <= 4) {
return RCC_HCLK_DIV4;
} else if (wanted_div <= 8) {
return RCC_HCLK_DIV8;
} else {
return RCC_HCLK_DIV16;
}
#endif
}
static uint32_t calc_apb2_div(uint32_t wanted_div) {
#if defined(STM32H7)
if (wanted_div <= 1) {
return RCC_APB2_DIV1;
} else if (wanted_div <= 2) {
return RCC_APB2_DIV2;
} else if (wanted_div <= 4) {
return RCC_APB2_DIV4;
} else if (wanted_div <= 8) {
return RCC_APB2_DIV8;
} else {
return RCC_APB2_DIV16;
}
#else
return calc_apb1_div(wanted_div);
#endif
}
#if defined(STM32F4) || defined(STM32F7) || defined(STM32G0) || defined(STM32G4) || defined(STM32H5) || defined(STM32H7)
int powerctrl_set_sysclk(uint32_t sysclk, uint32_t ahb, uint32_t apb1, uint32_t apb2) {
// Return straight away if the clocks are already at the desired frequency
if (sysclk == HAL_RCC_GetSysClockFreq()
&& ahb == HAL_RCC_GetHCLKFreq()
&& apb1 == HAL_RCC_GetPCLK1Freq()
#if !defined(STM32G0)
&& apb2 == HAL_RCC_GetPCLK2Freq()
#endif
) {
return 0;
}
// Default PLL parameters that give 48MHz on PLL48CK
uint32_t m = MICROPY_HW_CLK_VALUE / 1000000, n = 336, p = 2, q = 7;
uint32_t sysclk_source;
bool need_pll48 = false;
// Search for a valid PLL configuration that keeps USB at 48MHz
uint32_t sysclk_mhz = sysclk / 1000000;
for (const pll_freq_table_t *pll = &pll_freq_table[MP_ARRAY_SIZE(pll_freq_table) - 1]; pll >= &pll_freq_table[0]; --pll) {
uint32_t sys = PLL_FREQ_TABLE_SYS(*pll);
if (sys <= sysclk_mhz) {
m = PLL_FREQ_TABLE_M(*pll);
p = PLL_FREQ_TABLE_P(*pll);
if (m == 0) {
// special entry for using HSI directly
sysclk_source = RCC_SYSCLKSOURCE_HSI;
} else if (m == 1) {
// special entry for using HSE directly
sysclk_source = RCC_SYSCLKSOURCE_HSE;
} else {
// use PLL
sysclk_source = RCC_SYSCLKSOURCE_PLLCLK;
uint32_t vco_out = sys * p;
n = vco_out * m / (MICROPY_HW_CLK_VALUE / 1000000);
q = vco_out / 48;
#if HAVE_PLL48
need_pll48 = vco_out % 48 != 0;
#endif
}
goto set_clk;
}
}
return -MP_EINVAL;
set_clk:
// Let the USB CDC have a chance to process before we change the clock
mp_hal_delay_ms(5);
// Desired system clock source is in sysclk_source
RCC_ClkInitTypeDef RCC_ClkInitStruct;
#if defined(STM32G0) || defined(STM32G4)
RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_ALL;
#else
RCC_ClkInitStruct.ClockType = (RCC_CLOCKTYPE_SYSCLK | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2);
#endif
if (sysclk_source == RCC_SYSCLKSOURCE_PLLCLK) {
// Set HSE as system clock source to allow modification of the PLL configuration
// We then change to PLL after re-configuring PLL
#if MICROPY_HW_CLK_USE_HSI
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI;
#else
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSE;
#endif
} else {
// Directly set the system clock source as desired
RCC_ClkInitStruct.SYSCLKSource = sysclk_source;
}
// Determine the bus clock dividers
// Note: AHB freq required to be >= 14.2MHz for USB operation
RCC_ClkInitStruct.AHBCLKDivider = calc_ahb_div(sysclk / ahb);
#if defined(STM32H5)
ahb = sysclk >> AHBPrescTable[RCC_ClkInitStruct.AHBCLKDivider >> RCC_CFGR2_HPRE_Pos];
#elif defined(STM32H7)
// Do nothing.
#else
ahb = sysclk >> AHBPrescTable[RCC_ClkInitStruct.AHBCLKDivider >> RCC_CFGR_HPRE_Pos];
#endif
RCC_ClkInitStruct.APB1CLKDivider = calc_apb1_div(ahb / apb1);
#if !defined(STM32G0)
RCC_ClkInitStruct.APB2CLKDivider = calc_apb2_div(ahb / apb2);
#endif
#if defined(STM32H5)
RCC_ClkInitStruct.APB3CLKDivider = RCC_HCLK_DIV1;
#endif
#if defined(STM32H7)
RCC_ClkInitStruct.SYSCLKDivider = RCC_SYSCLK_DIV1;
RCC_ClkInitStruct.APB3CLKDivider = MICROPY_HW_CLK_APB3_DIV;
RCC_ClkInitStruct.APB4CLKDivider = MICROPY_HW_CLK_APB4_DIV;
#endif
#if MICROPY_HW_CLK_LAST_FREQ
// Save the bus dividers for use later
uint32_t h = RCC_ClkInitStruct.AHBCLKDivider >> 4;
uint32_t b1 = RCC_ClkInitStruct.APB1CLKDivider >> 10;
uint32_t b2 = RCC_ClkInitStruct.APB2CLKDivider >> 10;
#endif
// Configure clock
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_1) != HAL_OK) {
return -MP_EIO;
}
#if HAVE_PLL48
// Deselect PLLSAI as 48MHz source if we were using it
RCC->DCKCFGR2 &= ~RCC_DCKCFGR2_CK48MSEL;
// Turn PLLSAI off because we are changing PLLM (which drives PLLSAI)
RCC->CR &= ~RCC_CR_PLL48_ON;
#endif
// Re-configure PLL
// Even if we don't use the PLL for the system clock, we still need it for USB, RNG and SDIO
RCC_OscInitTypeDef RCC_OscInitStruct;
RCC_OscInitStruct.OscillatorType = MICROPY_HW_RCC_OSCILLATOR_TYPE;
RCC_OscInitStruct.HSEState = MICROPY_HW_RCC_HSE_STATE;
RCC_OscInitStruct.HSIState = MICROPY_HW_RCC_HSI_STATE;
#if defined(STM32G0) || defined(STM32H5)
RCC_OscInitStruct.HSIDiv = RCC_HSI_DIV1;
#endif
RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = MICROPY_HW_RCC_PLL_SRC;
RCC_OscInitStruct.PLL.PLLM = m;
RCC_OscInitStruct.PLL.PLLN = n;
RCC_OscInitStruct.PLL.PLLP = p;
RCC_OscInitStruct.PLL.PLLQ = q;
#if defined(STM32H5)
RCC_OscInitStruct.PLL.PLLR = 0;
if (MICROPY_HW_CLK_VALUE / 1000000 <= 2 * m) {
RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1_VCIRANGE_0; // 1-2MHz
} else if (MICROPY_HW_CLK_VALUE / 1000000 <= 4 * m) {
RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1_VCIRANGE_1; // 2-4MHz
} else if (MICROPY_HW_CLK_VALUE / 1000000 <= 8 * m) {
RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1_VCIRANGE_2; // 4-8MHz
} else {
RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1_VCIRANGE_3; // 8-16MHz
}
if (MICROPY_HW_CLK_VALUE / 1000000 * n <= 420 * m) {
RCC_OscInitStruct.PLL.PLLVCOSEL = RCC_PLL1_VCORANGE_MEDIUM; // 150-420MHz
} else {
RCC_OscInitStruct.PLL.PLLVCOSEL = RCC_PLL1_VCORANGE_WIDE; // 192-836MHz
}
RCC_OscInitStruct.PLL.PLLFRACN = 0;
#elif defined(STM32H7)
RCC_OscInitStruct.PLL.PLLR = 0;
if (MICROPY_HW_CLK_VALUE / 1000000 <= 2 * m) {
RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1VCIRANGE_0; // 1-2MHz
} else if (MICROPY_HW_CLK_VALUE / 1000000 <= 4 * m) {
RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1VCIRANGE_1; // 2-4MHz
} else if (MICROPY_HW_CLK_VALUE / 1000000 <= 8 * m) {
RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1VCIRANGE_2; // 4-8MHz
} else {
RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1VCIRANGE_3; // 8-16MHz
}
if (MICROPY_HW_CLK_VALUE / 1000000 * n <= 420 * m) {
RCC_OscInitStruct.PLL.PLLVCOSEL = RCC_PLL1VCOMEDIUM; // 150-420MHz
} else {
RCC_OscInitStruct.PLL.PLLVCOSEL = RCC_PLL1VCOWIDE; // 192-960MHz
}
RCC_OscInitStruct.PLL.PLLFRACN = 0;
#endif
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK) {
return -MP_EIO;
}
// Set PLL as system clock source if wanted
if (sysclk_source == RCC_SYSCLKSOURCE_PLLCLK) {
RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_SYSCLK;
int ret = powerctrl_rcc_clock_config_pll(&RCC_ClkInitStruct, sysclk_mhz, need_pll48);
if (ret != 0) {
return ret;
}
}
#if MICROPY_HW_CLK_LAST_FREQ
// Save settings in RTC backup register to reconfigure clocks on hard-reset
#if defined(STM32F7)
#define FREQ_BKP BKP31R
#else
#define FREQ_BKP BKP19R
#endif
// qqqqqqqq pppppppp nnnnnnnn nnmmmmmm
// qqqqQQQQ ppppppPP nNNNNNNN NNMMMMMM
// 222111HH HHQQQQPP nNNNNNNN NNMMMMMM
p = (p / 2) - 1;
RTC->FREQ_BKP = m
| (n << 6) | (p << 16) | (q << 18)
| (h << 22)
| (b1 << 26)
| (b2 << 29);
#endif
return 0;
}
#elif defined(STM32WB) || defined(STM32WL)
#if defined(STM32WB)
#include "stm32wbxx_ll_utils.h"
#define FLASH_LATENCY_MAX LL_FLASH_LATENCY_3
#else
#include "stm32wlxx_ll_utils.h"
#define FLASH_LATENCY_MAX LL_FLASH_LATENCY_2
#endif
#define LPR_THRESHOLD (2000000)
#define VOS2_THRESHOLD (16000000)
enum {
SYSCLK_MODE_NONE,
SYSCLK_MODE_MSI,
SYSCLK_MODE_HSE_64M,
};
int powerctrl_set_sysclk(uint32_t sysclk, uint32_t ahb, uint32_t apb1, uint32_t apb2) {
int sysclk_mode = SYSCLK_MODE_NONE;
uint32_t msirange = 0;
uint32_t sysclk_cur = HAL_RCC_GetSysClockFreq();
if (sysclk == sysclk_cur) {
// SYSCLK does not need changing.
} else if (sysclk == 64000000) {
sysclk_mode = SYSCLK_MODE_HSE_64M;
} else {
for (msirange = 0; msirange < MP_ARRAY_SIZE(MSIRangeTable); ++msirange) {
if (MSIRangeTable[msirange] != 0 && sysclk == MSIRangeTable[msirange]) {
sysclk_mode = SYSCLK_MODE_MSI;
break;
}
}
if (sysclk_mode == SYSCLK_MODE_NONE) {
// Unsupported SYSCLK value.
return -MP_EINVAL;
}
}
// Exit LPR if SYSCLK will increase beyond threshold.
if (LL_PWR_IsEnabledLowPowerRunMode()) {
if (sysclk > LPR_THRESHOLD) {
if (sysclk_cur < LPR_THRESHOLD) {
// Must select MSI=LPR_THRESHOLD=2MHz to exit LPR.
LL_RCC_MSI_SetRange(LL_RCC_MSIRANGE_5);
}
// Exit LPR and wait for the regulator to be ready.
LL_PWR_ExitLowPowerRunMode();
while (!LL_PWR_IsActiveFlag_REGLPF()) {
}
}
}
// Select VOS1 if SYSCLK will increase beyond threshold.
if (sysclk > VOS2_THRESHOLD) {
LL_PWR_SetRegulVoltageScaling(LL_PWR_REGU_VOLTAGE_SCALE1);
while (LL_PWR_IsActiveFlag_VOS()) {
}
}
if (sysclk_mode == SYSCLK_MODE_HSE_64M) {
SystemClock_Config();
} else if (sysclk_mode == SYSCLK_MODE_MSI) {
// Set flash latency to maximum to ensure the latency is large enough for
// both the current SYSCLK and the SYSCLK that will be selected below.
LL_FLASH_SetLatency(FLASH_LATENCY_MAX);
while (LL_FLASH_GetLatency() != FLASH_LATENCY_MAX) {
}
// Before changing the MSIRANGE value, if MSI is on then it must also be ready.
while ((RCC->CR & (RCC_CR_MSIRDY | RCC_CR_MSION)) == RCC_CR_MSION) {
}
LL_RCC_MSI_SetRange(msirange << RCC_CR_MSIRANGE_Pos);
// Clock SYSCLK from MSI.
LL_RCC_SetSysClkSource(LL_RCC_SYS_CLKSOURCE_MSI);
while (LL_RCC_GetSysClkSource() != LL_RCC_SYS_CLKSOURCE_STATUS_MSI) {
}
// Disable PLL to decrease power consumption.
LL_RCC_PLL_Disable();
while (LL_RCC_PLL_IsReady() != 0) {
}
LL_RCC_PLL_DisableDomain_SYS();
// Select VOS2 if possible.
if (sysclk <= VOS2_THRESHOLD) {
LL_PWR_SetRegulVoltageScaling(LL_PWR_REGU_VOLTAGE_SCALE2);
}
// Enter LPR if possible.
if (sysclk <= LPR_THRESHOLD) {
LL_PWR_EnterLowPowerRunMode();
}
// Configure flash latency for the new SYSCLK.
LL_SetFlashLatency(sysclk);
// Update HAL state and SysTick.
SystemCoreClockUpdate();
powerctrl_config_systick();
}
// Return straight away if the clocks are already at the desired frequency.
if (ahb == HAL_RCC_GetHCLKFreq()
&& apb1 == HAL_RCC_GetPCLK1Freq()
&& apb2 == HAL_RCC_GetPCLK2Freq()) {
return 0;
}
// Calculate and configure the bus clock dividers.
uint32_t cfgr = RCC->CFGR;
cfgr &= ~(7 << RCC_CFGR_PPRE2_Pos | 7 << RCC_CFGR_PPRE1_Pos | 0xf << RCC_CFGR_HPRE_Pos);
cfgr |= calc_ahb_div(sysclk / ahb);
cfgr |= calc_apb1_div(ahb / apb1);
cfgr |= calc_apb2_div(ahb / apb2) << (RCC_CFGR_PPRE2_Pos - RCC_CFGR_PPRE1_Pos);
RCC->CFGR = cfgr;
return 0;
}
#if defined(STM32WB)
static void powerctrl_switch_on_HSI(void) {
LL_RCC_HSI_Enable();
while (!LL_RCC_HSI_IsReady()) {
}
LL_RCC_SetSysClkSource(LL_RCC_SYS_CLKSOURCE_HSI);
LL_RCC_SetSMPSClockSource(LL_RCC_SMPS_CLKSOURCE_HSI);
while (LL_RCC_GetSysClkSource() != LL_RCC_SYS_CLKSOURCE_STATUS_HSI) {
}
return;
}
static void powerctrl_low_power_prep_wb55() {
// See WB55 specific documentation in AN5289 Rev 6, and in particular, Figure 6.
while (LL_HSEM_1StepLock(HSEM, CFG_HW_RCC_SEMID)) {
}
if (!LL_HSEM_1StepLock(HSEM, CFG_HW_ENTRY_STOP_MODE_SEMID)) {
if (LL_PWR_IsActiveFlag_C2DS() || LL_PWR_IsActiveFlag_C2SB()) {
// Release ENTRY_STOP_MODE semaphore
LL_HSEM_ReleaseLock(HSEM, CFG_HW_ENTRY_STOP_MODE_SEMID, 0);
powerctrl_switch_on_HSI();
}
} else {
powerctrl_switch_on_HSI();
}
// Release RCC semaphore
LL_HSEM_ReleaseLock(HSEM, CFG_HW_RCC_SEMID, 0);
}
static void powerctrl_low_power_exit_wb55() {
// Ensure the HSE/HSI clock configuration is correct so core2 can wake properly again.
// See WB55 specific documentation in AN5289 Rev 6, and in particular, Figure 7.
LL_HSEM_ReleaseLock(HSEM, CFG_HW_ENTRY_STOP_MODE_SEMID, 0);
// Acquire RCC semaphore before adjusting clocks.
while (LL_HSEM_1StepLock(HSEM, CFG_HW_RCC_SEMID)) {
}
if (LL_RCC_GetSysClkSource() == LL_RCC_SYS_CLKSOURCE_STATUS_HSI) {
// Restore the clock configuration of the application
LL_RCC_HSE_Enable();
__HAL_FLASH_SET_LATENCY(FLASH_LATENCY_1);
while (!LL_RCC_HSE_IsReady()) {
}
LL_RCC_SetSysClkSource(LL_RCC_SYS_CLKSOURCE_HSE);
while (LL_RCC_GetSysClkSource() != LL_RCC_SYS_CLKSOURCE_STATUS_HSE) {
}
}
// Release RCC semaphore
LL_HSEM_ReleaseLock(HSEM, CFG_HW_RCC_SEMID, 0);
}
#endif // defined(STM32WB)
#endif // defined(STM32WB) || defined(STM32WL)
#endif // !defined(STM32F0) && !defined(STM32G0) && !defined(STM32L0) && !defined(STM32L1) && !defined(STM32L4)
void powerctrl_enter_stop_mode(void) {
// Disable IRQs so that the IRQ that wakes the device from stop mode is not
// executed until after the clocks are reconfigured
uint32_t irq_state = disable_irq();
#if defined(STM32H7) || \
defined(STM32F427xx) || defined(STM32F437xx) || \
defined(STM32F429xx) || defined(STM32F439xx) || \
defined(STM32WB55xx) || defined(STM32WB35xx)
// Disable SysTick Interrupt
// Note: This seems to be required at least on the H7 REV Y,
// otherwise the MCU will leave stop mode immediately on entry.
// Note: According to ST Errata ES0206 Rev 18, Section 2.2.1 this is needed
// for STM32F427xx, STM32F437xx, STM32F429xx and STM32F439xx
// Note: According to ST Errata ES0394 Rev 11, Section 2.2.17 this is needed
// for STM32WB55xx and STM32WB35xx
SysTick->CTRL &= ~SysTick_CTRL_TICKINT_Msk;
#endif
#if defined(MICROPY_BOARD_ENTER_STOP)
MICROPY_BOARD_ENTER_STOP
#endif
#if defined(STM32L4)
// Configure the MSI as the clock source after waking up
__HAL_RCC_WAKEUPSTOP_CLK_CONFIG(RCC_STOP_WAKEUPCLOCK_MSI);
#endif
#if !defined(STM32F0) && !defined(STM32G0) && !defined(STM32G4) && !defined(STM32L0) && !defined(STM32L1) && !defined(STM32L4) && !defined(STM32WB) && !defined(STM32WL)
// takes longer to wake but reduces stop current
HAL_PWREx_EnableFlashPowerDown();
#endif
#if defined(STM32H5)
// Save RCC CR to re-enable OSCs and PLLs after wake up from low power mode.
uint32_t rcc_cr = RCC->CR;
// Save the current voltage scaling level to restore after exiting low power mode.
uint32_t vscaling = POWERCTRL_GET_VOLTAGE_SCALING();
#endif
#if defined(STM32H7)
// Save RCC CR to re-enable OSCs and PLLs after wake up from low power mode.
uint32_t rcc_cr = RCC->CR;
// Save the current voltage scaling level to restore after exiting low power mode.
uint32_t vscaling = POWERCTRL_GET_VOLTAGE_SCALING();
// If the current voltage scaling level is 0, switch to level 1 before entering low power mode.
if (vscaling == PWR_REGULATOR_VOLTAGE_SCALE0) {
__HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);
// Wait for PWR_FLAG_VOSRDY
while (!__HAL_PWR_GET_FLAG(PWR_FLAG_VOSRDY)) {
}
}
#endif
#if defined(STM32WB)
powerctrl_low_power_prep_wb55();
#endif
#if defined(STM32F7)
HAL_PWR_EnterSTOPMode((PWR_CR1_LPDS | PWR_CR1_LPUDS | PWR_CR1_FPDS | PWR_CR1_UDEN), PWR_STOPENTRY_WFI);
#else
HAL_PWR_EnterSTOPMode(PWR_LOWPOWERREGULATOR_ON, PWR_STOPENTRY_WFI);
#endif
// reconfigure the system clock after waking up
#if defined(STM32F0)
// Enable HSI48
__HAL_RCC_HSI48_ENABLE();
while (!__HAL_RCC_GET_FLAG(RCC_FLAG_HSI48RDY)) {
}
// Select HSI48 as system clock source
MODIFY_REG(RCC->CFGR, RCC_CFGR_SW, RCC_SYSCLKSOURCE_HSI48);
while (__HAL_RCC_GET_SYSCLK_SOURCE() != RCC_CFGR_SWS_HSI48) {
}
#else // defined(STM32F0)
#if defined(STM32H5) || defined(STM32H7)
// When exiting from Stop or Standby modes, the Run mode voltage scaling is reset to
// the default VOS3 value. Restore the voltage scaling to the previous voltage scale.
if (vscaling != POWERCTRL_GET_VOLTAGE_SCALING()) {
__HAL_PWR_VOLTAGESCALING_CONFIG(vscaling);
// Wait for PWR_FLAG_VOSRDY
while (!__HAL_PWR_GET_FLAG(PWR_FLAG_VOSRDY)) {
}
}
#endif
#if defined(STM32WB)
powerctrl_low_power_exit_wb55();
#endif
#if !defined(STM32L4)
// enable clock
__HAL_RCC_HSE_CONFIG(MICROPY_HW_RCC_HSE_STATE);
#if MICROPY_HW_CLK_USE_HSI
__HAL_RCC_HSI_ENABLE();
#endif
while (!__HAL_RCC_GET_FLAG(MICROPY_HW_RCC_FLAG_HSxRDY)) {
}
#endif
#if defined(STM32F7)
// Enable overdrive to reach 216MHz (if needed)
HAL_PWREx_EnableOverDrive();
#endif
#if defined(STM32H5)
// Enable PLL1, and switch the system clock source to PLL1P.
LL_RCC_PLL1_Enable();
while (!LL_RCC_PLL1_IsReady()) {
}
LL_RCC_SetSysClkSource(LL_RCC_SYS_CLKSOURCE_PLL1);
while (LL_RCC_GetSysClkSource() != LL_RCC_SYS_CLKSOURCE_STATUS_PLL1) {
}
#else // defined(STM32H5)
// enable PLL
__HAL_RCC_PLL_ENABLE();
while (!__HAL_RCC_GET_FLAG(RCC_FLAG_PLLRDY)) {
}
// select PLL as system clock source
MODIFY_REG(RCC->CFGR, RCC_CFGR_SW, RCC_SYSCLKSOURCE_PLLCLK);
#if defined(STM32H7)
while (__HAL_RCC_GET_SYSCLK_SOURCE() != RCC_CFGR_SWS_PLL1) {
}
#elif defined(STM32G0) || defined(STM32WB) || defined(STM32WL)
while (__HAL_RCC_GET_SYSCLK_SOURCE() != RCC_SYSCLKSOURCE_STATUS_PLLCLK) {
}
#else
while (__HAL_RCC_GET_SYSCLK_SOURCE() != RCC_CFGR_SWS_PLL) {
}
#endif
#endif // defined(STM32H5)
powerctrl_disable_hsi_if_unused();
#if HAVE_PLL48
if (RCC->DCKCFGR2 & RCC_DCKCFGR2_CK48MSEL) {
// Enable PLLSAI if it is selected as 48MHz source
RCC->CR |= RCC_CR_PLL48_ON;
while (!(RCC->CR & RCC_CR_PLL48_RDY)) {
}
}
#endif
#if defined(STM32H5)
if (rcc_cr & RCC_CR_HSI48ON) {
// Enable HSI48.
LL_RCC_HSI48_Enable();
while (!LL_RCC_HSI48_IsReady()) {
}
}
#endif
#if defined(STM32H7)
// Enable HSI
if (rcc_cr & RCC_CR_HSION) {
RCC->CR |= RCC_CR_HSION;
while (!(RCC->CR & RCC_CR_HSIRDY)) {
}
}
// Enable CSI
if (rcc_cr & RCC_CR_CSION) {
RCC->CR |= RCC_CR_CSION;
while (!(RCC->CR & RCC_CR_CSIRDY)) {
}
}
// Enable HSI48
if (rcc_cr & RCC_CR_HSI48ON) {
RCC->CR |= RCC_CR_HSI48ON;
while (!(RCC->CR & RCC_CR_HSI48RDY)) {
}
}
// Enable PLL2
if (rcc_cr & RCC_CR_PLL2ON) {
RCC->CR |= RCC_CR_PLL2ON;
while (!(RCC->CR & RCC_CR_PLL2RDY)) {
}
}
// Enable PLL3
if (rcc_cr & RCC_CR_PLL3ON) {
RCC->CR |= RCC_CR_PLL3ON;
while (!(RCC->CR & RCC_CR_PLL3RDY)) {
}
}
#endif
#if defined(STM32L4)
// Enable PLLSAI1 for peripherals that use it
RCC->CR |= RCC_CR_PLLSAI1ON;
while (!(RCC->CR & RCC_CR_PLLSAI1RDY)) {
}
#endif
#endif
#if defined(MICROPY_BOARD_LEAVE_STOP)
MICROPY_BOARD_LEAVE_STOP
#endif
#if defined(STM32H7) || \
defined(STM32F427xx) || defined(STM32F437xx) || \
defined(STM32F429xx) || defined(STM32F439xx) || \
defined(STM32WB55xx) || defined(STM32WB35xx)
// Enable SysTick Interrupt
SysTick->CTRL |= SysTick_CTRL_TICKINT_Msk;
#endif
// Enable IRQs now that all clocks are reconfigured
enable_irq(irq_state);
}
NORETURN void powerctrl_enter_standby_mode(void) {
rtc_init_finalise();
#if defined(MICROPY_BOARD_ENTER_STANDBY)
MICROPY_BOARD_ENTER_STANDBY
#endif
#if defined(STM32H7)
// Note: According to ST reference manual, RM0399, Rev 3, Section 7.7.10,
// before entering Standby mode, voltage scale VOS0 must not be active.
uint32_t vscaling = POWERCTRL_GET_VOLTAGE_SCALING();
if (vscaling == PWR_REGULATOR_VOLTAGE_SCALE0) {
__HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE3);
// Wait for PWR_FLAG_VOSRDY
while (!__HAL_PWR_GET_FLAG(PWR_FLAG_VOSRDY)) {
}
}
#endif
#if defined(STM32WB) && MICROPY_PY_BLUETOOTH
mp_bluetooth_deinit();
#endif
// We need to clear the PWR wake-up-flag before entering standby, since
// the flag may have been set by a previous wake-up event. Furthermore,
// we need to disable the wake-up sources while clearing this flag, so
// that if a source is active it does actually wake the device.
// See section 5.3.7 of RM0090.
// Note: we only support RTC ALRA, ALRB, WUT and TS.
// TODO support TAMP and WKUP (PA0 external pin).
#if defined(STM32F0) || defined(STM32L0)
#define CR_BITS (RTC_CR_ALRAIE | RTC_CR_WUTIE | RTC_CR_TSIE)
#define ISR_BITS (RTC_ISR_ALRAF | RTC_ISR_WUTF | RTC_ISR_TSF)
#elif defined(STM32G0) || defined(STM32G4) || defined(STM32H5) || defined(STM32WL)
#define CR_BITS (RTC_CR_ALRAIE | RTC_CR_ALRBIE | RTC_CR_WUTIE | RTC_CR_TSIE)
#define ISR_BITS (RTC_MISR_ALRAMF | RTC_MISR_ALRBMF | RTC_MISR_WUTMF | RTC_MISR_TSMF)
#elif defined(STM32H7A3xx) || defined(STM32H7A3xxQ) || defined(STM32H7B3xx) || defined(STM32H7B3xxQ)
#define CR_BITS (RTC_CR_ALRAIE | RTC_CR_ALRBIE | RTC_CR_WUTIE | RTC_CR_TSIE)
#define SR_BITS (RTC_SR_ALRAF | RTC_SR_ALRBF | RTC_SR_WUTF | RTC_SR_TSF)
#else
#define CR_BITS (RTC_CR_ALRAIE | RTC_CR_ALRBIE | RTC_CR_WUTIE | RTC_CR_TSIE)
#define ISR_BITS (RTC_ISR_ALRAF | RTC_ISR_ALRBF | RTC_ISR_WUTF | RTC_ISR_TSF)
#endif
// save RTC interrupts
uint32_t save_irq_bits = RTC->CR & CR_BITS;
// disable register write protection
RTC->WPR = 0xca;
RTC->WPR = 0x53;
// disable RTC interrupts
RTC->CR &= ~CR_BITS;
// clear RTC wake-up flags
#if defined(SR_BITS)
RTC->SR &= ~SR_BITS;
#elif defined(STM32G0) || defined(STM32G4) || defined(STM32H5) || defined(STM32WL)
RTC->MISR &= ~ISR_BITS;
#else
RTC->ISR &= ~ISR_BITS;
#endif
#if defined(STM32F7)
// Save EWUP state
uint32_t csr2_ewup = PWR->CSR2 & (PWR_CSR2_EWUP6 | PWR_CSR2_EWUP5 | PWR_CSR2_EWUP4 | PWR_CSR2_EWUP3 | PWR_CSR2_EWUP2 | PWR_CSR2_EWUP1);
// disable wake-up flags
PWR->CSR2 &= ~(PWR_CSR2_EWUP6 | PWR_CSR2_EWUP5 | PWR_CSR2_EWUP4 | PWR_CSR2_EWUP3 | PWR_CSR2_EWUP2 | PWR_CSR2_EWUP1);
// clear global wake-up flag
PWR->CR2 |= PWR_CR2_CWUPF6 | PWR_CR2_CWUPF5 | PWR_CR2_CWUPF4 | PWR_CR2_CWUPF3 | PWR_CR2_CWUPF2 | PWR_CR2_CWUPF1;
// Restore EWUP state
PWR->CSR2 |= csr2_ewup;
#elif defined(STM32H5)
LL_PWR_ClearFlag_WU();
#elif defined(STM32H7)
// Clear and mask D1 EXTIs.
EXTI_D1->PR1 = 0x3fffffu;
EXTI_D1->IMR1 &= ~(0xFFFFu); // 16 lines
#if defined(EXTI_D2)
// Clear and mask D2 EXTIs.
EXTI_D2->PR1 = 0x3fffffu;
EXTI_D2->IMR1 &= ~(0xFFFFu); // 16 lines
#endif
// Clear all wake-up flags.
PWR->WKUPCR |= PWR_WAKEUP_FLAG_ALL;
#elif defined(STM32G0) || defined(STM32G4) || defined(STM32L4) || defined(STM32WB)
// clear all wake-up flags
PWR->SCR |= PWR_SCR_CWUF5 | PWR_SCR_CWUF4 | PWR_SCR_CWUF3 | PWR_SCR_CWUF2 | PWR_SCR_CWUF1;
// TODO
#elif defined(STM32WL)
// clear all wake-up flags
PWR->SCR |= PWR_SCR_CWUF3 | PWR_SCR_CWUF2 | PWR_SCR_CWUF1;
#else
// clear global wake-up flag
PWR->CR |= PWR_CR_CWUF;
#endif
// enable previously-enabled RTC interrupts
RTC->CR |= save_irq_bits;
// enable register write protection
RTC->WPR = 0xff;
#if defined(STM32F7)
// Enable the internal (eg RTC) wakeup sources
// See Errata 2.2.2 "Wakeup from Standby mode when the back-up SRAM regulator is enabled"
PWR->CSR1 |= PWR_CSR1_EIWUP;
#endif
#if defined(NDEBUG) && defined(DBGMCU)
// Disable Debug MCU.
DBGMCU->CR = 0;
#endif
#if defined(STM32WB)
powerctrl_low_power_prep_wb55();
#endif
// enter standby mode
HAL_PWR_EnterSTANDBYMode();
// MCU is reset on exit from standby, but just in case it's not, do an explicit reset.
powerctrl_mcu_reset();
}