circuitpython/ports/stm/supervisor/port.c

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/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2017 Scott Shawcroft for Adafruit Industries
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* Copyright (c) 2019 Lucian Copeland for Adafruit Industries
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*
* 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 <stdint.h>
#include "supervisor/port.h"
#include "supervisor/board.h"
#include "lib/timeutils/timeutils.h"
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#include "common-hal/microcontroller/Pin.h"
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#if CIRCUITPY_BUSIO
#include "common-hal/busio/I2C.h"
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#include "common-hal/busio/SPI.h"
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#include "common-hal/busio/UART.h"
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#endif
#if CIRCUITPY_PULSEIO
#include "common-hal/pulseio/PulseOut.h"
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#include "common-hal/pulseio/PulseIn.h"
#endif
#if CIRCUITPY_PWMIO
#include "common-hal/pwmio/PWMOut.h"
#endif
#if CIRCUITPY_PULSEIO || CIRCUITPY_PWMIO
#include "timers.h"
#endif
#if CIRCUITPY_SDIOIO
#include "common-hal/sdioio/SDCard.h"
#endif
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#include "clocks.h"
#include "gpio.h"
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#include STM32_HAL_H
Add some NORETURN attributes I have a function where it should be impossible to reach the end, so I put in a safe-mode reset at the bottom: ``` int find_unused_slot(void) { // precondition: you already verified that a slot was available for (int i=0; i<NUM_SLOTS; i++) { if( slot_free(i)) { return i; } } safe_mode_reset(MICROPY_FATAL_ERROR); } ``` However, the compiler still gave a diagnostic, because safe_mode_reset was not declared NORETURN. So I started by teaching the compiler that reset_into_safe_mode never returned. This leads at least one level deeper due to reset_cpu needing to be a NORETURN function. Each port is a little different in this area. I also marked reset_to_bootloader as NORETURN. Additional notes: * stm32's reset_to_bootloader was not implemented, but now does a bare reset. Most stm32s are not fitted with uf2 bootloaders anyway. * ditto cxd56 * esp32s2 did not implement reset_cpu at all. I used esp_restart(). (not tested) * litex did not implement reset_cpu at all. I used reboot_ctrl_write. But notably this is what reset_to_bootloader already did, so one or the other must be incorrect (not tested). reboot_ctrl_write cannot be declared NORETURN, as it returns unless the special value 0xac is written), so a new unreachable forever-loop is added. * cxd56's reset is via a boardctl() call which can't generically be declared NORETURN, so a new unreacahble "for(;;)" forever-loop is added. * In several places, NVIC_SystemReset is redeclared with NORETURN applied. This is accepted just fine by gcc. I chose this as preferable to editing the multiple copies of CMSIS headers where it is normally declared. * the stub safe_mode reset simply aborts. This is used in mpy-cross.
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void NVIC_SystemReset(void) NORETURN;
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#if (CPY_STM32H7) || (CPY_STM32F7)
// Device memories must be accessed in order.
#define DEVICE 2
// Normal memory can have accesses reorder and prefetched.
#define NORMAL 0
// Prevents instruction access.
#define NO_EXECUTION 1
#define EXECUTION 0
// Shareable if the memory system manages coherency.
#define NOT_SHAREABLE 0
#define SHAREABLE 1
#define NOT_CACHEABLE 0
#define CACHEABLE 1
#define NOT_BUFFERABLE 0
#define BUFFERABLE 1
#define NO_SUBREGIONS 0
extern uint32_t _ld_stack_top;
extern uint32_t _ld_d1_ram_bss_start;
extern uint32_t _ld_d1_ram_bss_size;
extern uint32_t _ld_d1_ram_data_destination;
extern uint32_t _ld_d1_ram_data_size;
extern uint32_t _ld_d1_ram_data_flash_copy;
extern uint32_t _ld_dtcm_bss_start;
extern uint32_t _ld_dtcm_bss_size;
extern uint32_t _ld_dtcm_data_destination;
extern uint32_t _ld_dtcm_data_size;
extern uint32_t _ld_dtcm_data_flash_copy;
extern uint32_t _ld_itcm_destination;
extern uint32_t _ld_itcm_size;
extern uint32_t _ld_itcm_flash_copy;
extern void main(void);
extern void SystemInit(void);
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// This replaces the Reset_Handler in gcc/startup_*.s, calls SystemInit from system_*.c
__attribute__((used, naked)) void Reset_Handler(void) {
__disable_irq();
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__set_MSP((uint32_t)&_ld_stack_top);
/* Disable MPU */
ARM_MPU_Disable();
// Copy all of the itcm code to run from ITCM. Do this while the MPU is disabled because we write
// protect it.
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for (uint32_t i = 0; i < ((size_t)&_ld_itcm_size) / 4; i++) {
(&_ld_itcm_destination)[i] = (&_ld_itcm_flash_copy)[i];
}
// The first number in RBAR is the region number. When searching for a policy, the region with
// the highest number wins. If none match, then the default policy set at enable applies.
// Mark all the flash the same until instructed otherwise.
MPU->RBAR = ARM_MPU_RBAR(11, 0x08000000U);
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MPU->RASR = ARM_MPU_RASR(EXECUTION, ARM_MPU_AP_FULL, NORMAL, NOT_SHAREABLE, CACHEABLE, BUFFERABLE, NO_SUBREGIONS, CPY_FLASH_REGION_SIZE);
// This the ITCM. Set it to read-only because we've loaded everything already and it's easy to
// accidentally write the wrong value to 0x00000000 (aka NULL).
MPU->RBAR = ARM_MPU_RBAR(12, 0x00000000U);
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MPU->RASR = ARM_MPU_RASR(EXECUTION, ARM_MPU_AP_RO, NORMAL, NOT_SHAREABLE, CACHEABLE, BUFFERABLE, NO_SUBREGIONS, CPY_ITCM_REGION_SIZE);
// This the DTCM.
MPU->RBAR = ARM_MPU_RBAR(14, 0x20000000U);
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MPU->RASR = ARM_MPU_RASR(EXECUTION, ARM_MPU_AP_FULL, NORMAL, NOT_SHAREABLE, CACHEABLE, BUFFERABLE, NO_SUBREGIONS, CPY_DTCM_REGION_SIZE);
// This is AXI SRAM (D1).
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MPU->RBAR = ARM_MPU_RBAR(15, CPY_SRAM_START_ADDR);
MPU->RASR = ARM_MPU_RASR(EXECUTION, ARM_MPU_AP_FULL, NORMAL, NOT_SHAREABLE, CACHEABLE, BUFFERABLE, CPY_SRAM_SUBMASK, CPY_SRAM_REGION_SIZE);
/* Enable MPU */
ARM_MPU_Enable(MPU_CTRL_PRIVDEFENA_Msk);
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// Copy all of the data to run from DTCM.
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for (uint32_t i = 0; i < ((size_t)&_ld_dtcm_data_size) / 4; i++) {
(&_ld_dtcm_data_destination)[i] = (&_ld_dtcm_data_flash_copy)[i];
}
// Clear DTCM bss.
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for (uint32_t i = 0; i < ((size_t)&_ld_dtcm_bss_size) / 4; i++) {
(&_ld_dtcm_bss_start)[i] = 0;
}
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// Copy all of the data to run from D1 RAM.
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for (uint32_t i = 0; i < ((size_t)&_ld_d1_ram_data_size) / 4; i++) {
(&_ld_d1_ram_data_destination)[i] = (&_ld_d1_ram_data_flash_copy)[i];
}
// Clear D1 RAM bss.
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for (uint32_t i = 0; i < ((size_t)&_ld_d1_ram_bss_size) / 4; i++) {
(&_ld_d1_ram_bss_start)[i] = 0;
}
SystemInit();
__enable_irq();
main();
}
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#endif // end H7 specific code
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// Low power clock variables
static volatile uint32_t systick_ms;
static RTC_HandleTypeDef _hrtc;
#if BOARD_HAS_LOW_SPEED_CRYSTAL
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static uint32_t rtc_clock_frequency = LSE_VALUE;
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#else
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static uint32_t rtc_clock_frequency = LSI_VALUE;
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#endif
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safe_mode_t port_init(void) {
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HAL_Init(); // Turns on SysTick
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__HAL_RCC_SYSCFG_CLK_ENABLE();
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#if (CPY_STM32F4)
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__HAL_RCC_PWR_CLK_ENABLE();
#endif
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stm32_peripherals_clocks_init();
stm32_peripherals_gpio_init();
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// RTC oscillator selection is handled in peripherals/<family>/<line>/clocks.c
__HAL_RCC_RTC_ENABLE();
_hrtc.Instance = RTC;
_hrtc.Init.HourFormat = RTC_HOURFORMAT_24;
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// Divide async as little as possible so that we have rtc_clock_frequency count in subseconds.
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// This ensures our timing > 1 second is correct.
_hrtc.Init.AsynchPrediv = 0x0;
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_hrtc.Init.SynchPrediv = rtc_clock_frequency - 1;
_hrtc.Init.OutPut = RTC_OUTPUT_DISABLE;
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HAL_RTC_Init(&_hrtc);
HAL_RTCEx_EnableBypassShadow(&_hrtc);
HAL_NVIC_EnableIRQ(RTC_Alarm_IRQn);
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// Turn off SysTick
SysTick->CTRL = 0;
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return NO_SAFE_MODE;
}
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void HAL_Delay(uint32_t delay_ms) {
if (SysTick->CTRL != 0) {
// SysTick is on, so use it
uint32_t tickstart = systick_ms;
while (systick_ms - tickstart < delay_ms) {
}
} else {
mp_hal_delay_ms(delay_ms);
}
}
uint32_t HAL_GetTick() {
if (SysTick->CTRL != 0) {
return systick_ms;
} else {
uint8_t subticks;
uint32_t result = (uint32_t)port_get_raw_ticks(&subticks);
return result;
}
}
void SysTick_Handler(void) {
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systick_ms += 1;
// Read the CTRL register to clear the SysTick interrupt.
SysTick->CTRL;
}
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void reset_port(void) {
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reset_all_pins();
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#if CIRCUITPY_BUSIO
i2c_reset();
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spi_reset();
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uart_reset();
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#endif
#if CIRCUITPY_SDIOIO
sdioio_reset();
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#endif
#if CIRCUITPY_PULSEIO || CIRCUITPY_PWMIO
timers_reset();
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#endif
#if CIRCUITPY_PULSEIO
pulseout_reset();
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pulsein_reset();
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#endif
#if CIRCUITPY_PWMIO
pwmout_reset();
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#endif
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}
void reset_to_bootloader(void) {
Add some NORETURN attributes I have a function where it should be impossible to reach the end, so I put in a safe-mode reset at the bottom: ``` int find_unused_slot(void) { // precondition: you already verified that a slot was available for (int i=0; i<NUM_SLOTS; i++) { if( slot_free(i)) { return i; } } safe_mode_reset(MICROPY_FATAL_ERROR); } ``` However, the compiler still gave a diagnostic, because safe_mode_reset was not declared NORETURN. So I started by teaching the compiler that reset_into_safe_mode never returned. This leads at least one level deeper due to reset_cpu needing to be a NORETURN function. Each port is a little different in this area. I also marked reset_to_bootloader as NORETURN. Additional notes: * stm32's reset_to_bootloader was not implemented, but now does a bare reset. Most stm32s are not fitted with uf2 bootloaders anyway. * ditto cxd56 * esp32s2 did not implement reset_cpu at all. I used esp_restart(). (not tested) * litex did not implement reset_cpu at all. I used reboot_ctrl_write. But notably this is what reset_to_bootloader already did, so one or the other must be incorrect (not tested). reboot_ctrl_write cannot be declared NORETURN, as it returns unless the special value 0xac is written), so a new unreachable forever-loop is added. * cxd56's reset is via a boardctl() call which can't generically be declared NORETURN, so a new unreacahble "for(;;)" forever-loop is added. * In several places, NVIC_SystemReset is redeclared with NORETURN applied. This is accepted just fine by gcc. I chose this as preferable to editing the multiple copies of CMSIS headers where it is normally declared. * the stub safe_mode reset simply aborts. This is used in mpy-cross.
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NVIC_SystemReset();
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}
void reset_cpu(void) {
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NVIC_SystemReset();
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}
extern uint32_t _ld_heap_start, _ld_heap_end, _ld_stack_top, _ld_stack_bottom;
uint32_t *port_heap_get_bottom(void) {
return &_ld_heap_start;
}
uint32_t *port_heap_get_top(void) {
return &_ld_heap_end;
}
bool port_has_fixed_stack(void) {
return false;
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}
uint32_t *port_stack_get_limit(void) {
return &_ld_stack_bottom;
}
uint32_t *port_stack_get_top(void) {
return &_ld_stack_top;
}
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extern uint32_t _ebss;
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// Place the word to save just after our BSS section that gets blanked.
void port_set_saved_word(uint32_t value) {
_ebss = value;
}
uint32_t port_get_saved_word(void) {
return _ebss;
}
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__attribute__((used)) void MemManage_Handler(void) {
reset_into_safe_mode(MEM_MANAGE);
while (true) {
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asm ("nop;");
}
}
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__attribute__((used)) void BusFault_Handler(void) {
reset_into_safe_mode(MEM_MANAGE);
while (true) {
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asm ("nop;");
}
}
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__attribute__((used)) void UsageFault_Handler(void) {
reset_into_safe_mode(MEM_MANAGE);
while (true) {
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asm ("nop;");
}
}
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__attribute__((used)) void HardFault_Handler(void) {
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reset_into_safe_mode(HARD_CRASH);
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while (true) {
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asm ("nop;");
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}
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}
// This function is called often for timing so we cache the seconds elapsed computation based on the
// register value. The STM HAL always does shifts and conversion if we use it directly.
volatile uint32_t seconds_to_date = 0;
volatile uint32_t cached_date = 0;
volatile uint32_t seconds_to_minute = 0;
volatile uint32_t cached_hours_minutes = 0;
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uint64_t port_get_raw_ticks(uint8_t *subticks) {
// Disable IRQs to ensure we read all of the RTC registers as close in time as possible. Read
// SSR twice to make sure we didn't read across a tick.
__disable_irq();
uint32_t first_ssr = (uint32_t)(RTC->SSR);
uint32_t time = (uint32_t)(RTC->TR & RTC_TR_RESERVED_MASK);
uint32_t date = (uint32_t)(RTC->DR & RTC_DR_RESERVED_MASK);
uint32_t ssr = (uint32_t)(RTC->SSR);
while (ssr != first_ssr) {
first_ssr = ssr;
time = (uint32_t)(RTC->TR & RTC_TR_RESERVED_MASK);
date = (uint32_t)(RTC->DR & RTC_DR_RESERVED_MASK);
ssr = (uint32_t)(RTC->SSR);
}
__enable_irq();
uint32_t subseconds = rtc_clock_frequency - 1 - ssr;
if (date != cached_date) {
uint32_t year = (uint8_t)((date & (RTC_DR_YT | RTC_DR_YU)) >> 16U);
uint8_t month = (uint8_t)((date & (RTC_DR_MT | RTC_DR_MU)) >> 8U);
uint8_t day = (uint8_t)(date & (RTC_DR_DT | RTC_DR_DU));
// Add 2000 since the year is only the last two digits.
year = 2000 + (uint32_t)RTC_Bcd2ToByte(year);
month = (uint8_t)RTC_Bcd2ToByte(month);
day = (uint8_t)RTC_Bcd2ToByte(day);
seconds_to_date = timeutils_seconds_since_2000(year, month, day, 0, 0, 0);
cached_date = date;
}
uint32_t hours_minutes = time & (RTC_TR_HT | RTC_TR_HU | RTC_TR_MNT | RTC_TR_MNU);
if (hours_minutes != cached_hours_minutes) {
uint8_t hours = (uint8_t)((time & (RTC_TR_HT | RTC_TR_HU)) >> 16U);
uint8_t minutes = (uint8_t)((time & (RTC_TR_MNT | RTC_TR_MNU)) >> 8U);
hours = (uint8_t)RTC_Bcd2ToByte(hours);
minutes = (uint8_t)RTC_Bcd2ToByte(minutes);
seconds_to_minute = 60 * (60 * hours + minutes);
cached_hours_minutes = hours_minutes;
}
uint8_t seconds = (uint8_t)(time & (RTC_TR_ST | RTC_TR_SU));
seconds = (uint8_t)RTC_Bcd2ToByte(seconds);
if (subticks != NULL) {
*subticks = subseconds % 32;
}
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uint64_t raw_ticks = ((uint64_t)1024) * (seconds_to_date + seconds_to_minute + seconds) + subseconds / 32;
return raw_ticks;
}
void RTC_WKUP_IRQHandler(void) {
supervisor_tick();
__HAL_RTC_WAKEUPTIMER_CLEAR_FLAG(&_hrtc, RTC_FLAG_WUTF);
__HAL_RTC_WAKEUPTIMER_EXTI_CLEAR_FLAG();
}
volatile bool alarmed_already = false;
void RTC_Alarm_IRQHandler(void) {
HAL_RTC_DeactivateAlarm(&_hrtc, RTC_ALARM_A);
__HAL_RTC_ALARM_EXTI_CLEAR_FLAG();
__HAL_RTC_ALARM_CLEAR_FLAG(&_hrtc, RTC_FLAG_ALRAF);
alarmed_already = true;
}
// Enable 1/1024 second tick.
void port_enable_tick(void) {
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HAL_RTCEx_SetWakeUpTimer_IT(&_hrtc, rtc_clock_frequency / 1024 / 2, RTC_WAKEUPCLOCK_RTCCLK_DIV2);
HAL_NVIC_SetPriority(RTC_WKUP_IRQn, 1, 0U);
HAL_NVIC_EnableIRQ(RTC_WKUP_IRQn);
}
extern volatile uint32_t autoreload_delay_ms;
// Disable 1/1024 second tick.
void port_disable_tick(void) {
HAL_NVIC_DisableIRQ(RTC_WKUP_IRQn);
HAL_RTCEx_DeactivateWakeUpTimer(&_hrtc);
}
void port_interrupt_after_ticks(uint32_t ticks) {
uint64_t raw_ticks = port_get_raw_ticks(NULL) + ticks;
RTC_AlarmTypeDef alarm;
if (ticks > 1024) {
timeutils_struct_time_t tm;
timeutils_seconds_since_2000_to_struct_time(raw_ticks / 1024, &tm);
alarm.AlarmTime.Hours = tm.tm_hour;
alarm.AlarmTime.Minutes = tm.tm_min;
alarm.AlarmTime.Seconds = tm.tm_sec;
alarm.AlarmDateWeekDay = tm.tm_mday;
// Masking here means that the value is ignored so we set none.
alarm.AlarmMask = RTC_ALARMMASK_NONE;
} else {
// Masking here means that the value is ignored so we set them all. Only the subseconds
// value matters.
alarm.AlarmMask = RTC_ALARMMASK_ALL;
}
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alarm.AlarmTime.SubSeconds = rtc_clock_frequency - 1 -
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((raw_ticks % 1024) * 32);
alarm.AlarmTime.DayLightSaving = RTC_DAYLIGHTSAVING_NONE;
alarm.AlarmTime.StoreOperation = RTC_STOREOPERATION_SET;
// Masking here means that the bits are ignored so we set none of them.
alarm.AlarmSubSecondMask = RTC_ALARMSUBSECONDMASK_NONE;
alarm.AlarmDateWeekDaySel = RTC_ALARMDATEWEEKDAYSEL_DATE;
alarm.Alarm = RTC_ALARM_A;
HAL_RTC_SetAlarm_IT(&_hrtc, &alarm, RTC_FORMAT_BIN);
alarmed_already = false;
}
void port_idle_until_interrupt(void) {
// Clear the FPU interrupt because it can prevent us from sleeping.
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if (__get_FPSCR() & ~(0x9f)) {
__set_FPSCR(__get_FPSCR() & ~(0x9f));
(void)__get_FPSCR();
}
if (alarmed_already) {
return;
}
__WFI();
}
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// Required by __libc_init_array in startup code if we are compiling using
// -nostdlib/-nostartfiles.
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void _init(void) {
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}