micropython/ports/stm32/main.c

767 lines
22 KiB
C

/*
* 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 <stdio.h>
#include <string.h>
#include "py/runtime.h"
#include "py/stackctrl.h"
#include "py/gc.h"
#include "py/mphal.h"
#include "lib/mp-readline/readline.h"
#include "lib/utils/pyexec.h"
#include "lib/oofatfs/ff.h"
#include "extmod/vfs.h"
#include "extmod/vfs_fat.h"
#if MICROPY_PY_LWIP
#include "lwip/init.h"
#include "lwip/apps/mdns.h"
#include "drivers/cyw43/cyw43.h"
#endif
#if MICROPY_BLUETOOTH_NIMBLE
#include "extmod/modbluetooth.h"
#endif
#include "mpu.h"
#include "rfcore.h"
#include "systick.h"
#include "pendsv.h"
#include "powerctrl.h"
#include "pybthread.h"
#include "gccollect.h"
#include "factoryreset.h"
#include "modmachine.h"
#include "softtimer.h"
#include "i2c.h"
#include "spi.h"
#include "uart.h"
#include "timer.h"
#include "led.h"
#include "pin.h"
#include "extint.h"
#include "usrsw.h"
#include "usb.h"
#include "rtc.h"
#include "storage.h"
#include "sdcard.h"
#include "sdram.h"
#include "rng.h"
#include "accel.h"
#include "servo.h"
#include "dac.h"
#include "can.h"
#include "modnetwork.h"
#if MICROPY_PY_THREAD
STATIC pyb_thread_t pyb_thread_main;
#endif
#if MICROPY_HW_ENABLE_STORAGE
STATIC fs_user_mount_t fs_user_mount_flash;
#endif
#if defined(MICROPY_HW_UART_REPL)
#ifndef MICROPY_HW_UART_REPL_RXBUF
#define MICROPY_HW_UART_REPL_RXBUF (260)
#endif
STATIC pyb_uart_obj_t pyb_uart_repl_obj;
STATIC uint8_t pyb_uart_repl_rxbuf[MICROPY_HW_UART_REPL_RXBUF];
#endif
void flash_error(int n) {
for (int i = 0; i < n; i++) {
led_state(PYB_LED_RED, 1);
led_state(PYB_LED_GREEN, 0);
mp_hal_delay_ms(250);
led_state(PYB_LED_RED, 0);
led_state(PYB_LED_GREEN, 1);
mp_hal_delay_ms(250);
}
led_state(PYB_LED_GREEN, 0);
}
void NORETURN __fatal_error(const char *msg) {
for (volatile uint delay = 0; delay < 10000000; delay++) {
}
led_state(1, 1);
led_state(2, 1);
led_state(3, 1);
led_state(4, 1);
mp_hal_stdout_tx_strn("\nFATAL ERROR:\n", 14);
mp_hal_stdout_tx_strn(msg, strlen(msg));
for (uint i = 0;;) {
led_toggle(((i++) & 3) + 1);
for (volatile uint delay = 0; delay < 10000000; delay++) {
}
if (i >= 16) {
// to conserve power
__WFI();
}
}
}
void nlr_jump_fail(void *val) {
printf("FATAL: uncaught exception %p\n", val);
mp_obj_print_exception(&mp_plat_print, MP_OBJ_FROM_PTR(val));
__fatal_error("");
}
#ifndef NDEBUG
void MP_WEAK __assert_func(const char *file, int line, const char *func, const char *expr) {
(void)func;
printf("Assertion '%s' failed, at file %s:%d\n", expr, file, line);
__fatal_error("");
}
#endif
STATIC mp_obj_t pyb_main(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
static const mp_arg_t allowed_args[] = {
{ MP_QSTR_opt, MP_ARG_INT, {.u_int = 0} }
};
if (mp_obj_is_str(pos_args[0])) {
MP_STATE_PORT(pyb_config_main) = pos_args[0];
// parse args
mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
#if MICROPY_ENABLE_COMPILER
MP_STATE_VM(mp_optimise_value) = args[0].u_int;
#endif
}
return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_KW(pyb_main_obj, 1, pyb_main);
#if MICROPY_HW_ENABLE_STORAGE
// avoid inlining to avoid stack usage within main()
MP_NOINLINE STATIC bool init_flash_fs(uint reset_mode) {
// init the vfs object
fs_user_mount_t *vfs_fat = &fs_user_mount_flash;
vfs_fat->blockdev.flags = 0;
pyb_flash_init_vfs(vfs_fat);
// try to mount the flash
FRESULT res = f_mount(&vfs_fat->fatfs);
if (reset_mode == 3 || res == FR_NO_FILESYSTEM) {
// no filesystem, or asked to reset it, so create a fresh one
// LED on to indicate creation of LFS
led_state(PYB_LED_GREEN, 1);
uint32_t start_tick = HAL_GetTick();
uint8_t working_buf[FF_MAX_SS];
res = f_mkfs(&vfs_fat->fatfs, FM_FAT, 0, working_buf, sizeof(working_buf));
if (res == FR_OK) {
// success creating fresh LFS
} else {
printf("MPY: can't create flash filesystem\n");
return false;
}
// set label
f_setlabel(&vfs_fat->fatfs, MICROPY_HW_FLASH_FS_LABEL);
// populate the filesystem with factory files
factory_reset_make_files(&vfs_fat->fatfs);
// keep LED on for at least 200ms
systick_wait_at_least(start_tick, 200);
led_state(PYB_LED_GREEN, 0);
} else if (res == FR_OK) {
// mount sucessful
} else {
fail:
printf("MPY: can't mount flash\n");
return false;
}
// mount the flash device (there should be no other devices mounted at this point)
// we allocate this structure on the heap because vfs->next is a root pointer
mp_vfs_mount_t *vfs = m_new_obj_maybe(mp_vfs_mount_t);
if (vfs == NULL) {
goto fail;
}
vfs->str = "/flash";
vfs->len = 6;
vfs->obj = MP_OBJ_FROM_PTR(vfs_fat);
vfs->next = NULL;
MP_STATE_VM(vfs_mount_table) = vfs;
// The current directory is used as the boot up directory.
// It is set to the internal flash filesystem by default.
MP_STATE_PORT(vfs_cur) = vfs;
return true;
}
#endif
#if MICROPY_HW_SDCARD_MOUNT_AT_BOOT
STATIC bool init_sdcard_fs(void) {
bool first_part = true;
for (int part_num = 1; part_num <= 4; ++part_num) {
// create vfs object
fs_user_mount_t *vfs_fat = m_new_obj_maybe(fs_user_mount_t);
mp_vfs_mount_t *vfs = m_new_obj_maybe(mp_vfs_mount_t);
if (vfs == NULL || vfs_fat == NULL) {
break;
}
vfs_fat->blockdev.flags = MP_BLOCKDEV_FLAG_FREE_OBJ;
sdcard_init_vfs(vfs_fat, part_num);
// try to mount the partition
FRESULT res = f_mount(&vfs_fat->fatfs);
if (res != FR_OK) {
// couldn't mount
m_del_obj(fs_user_mount_t, vfs_fat);
m_del_obj(mp_vfs_mount_t, vfs);
} else {
// mounted via FatFs, now mount the SD partition in the VFS
if (first_part) {
// the first available partition is traditionally called "sd" for simplicity
vfs->str = "/sd";
vfs->len = 3;
} else {
// subsequent partitions are numbered by their index in the partition table
if (part_num == 2) {
vfs->str = "/sd2";
} else if (part_num == 2) {
vfs->str = "/sd3";
} else {
vfs->str = "/sd4";
}
vfs->len = 4;
}
vfs->obj = MP_OBJ_FROM_PTR(vfs_fat);
vfs->next = NULL;
for (mp_vfs_mount_t **m = &MP_STATE_VM(vfs_mount_table);; m = &(*m)->next) {
if (*m == NULL) {
*m = vfs;
break;
}
}
#if MICROPY_HW_ENABLE_USB
if (pyb_usb_storage_medium == PYB_USB_STORAGE_MEDIUM_NONE) {
// if no USB MSC medium is selected then use the SD card
pyb_usb_storage_medium = PYB_USB_STORAGE_MEDIUM_SDCARD;
}
#endif
#if MICROPY_HW_ENABLE_USB
// only use SD card as current directory if that's what the USB medium is
if (pyb_usb_storage_medium == PYB_USB_STORAGE_MEDIUM_SDCARD)
#endif
{
if (first_part) {
// use SD card as current directory
MP_STATE_PORT(vfs_cur) = vfs;
}
}
first_part = false;
}
}
if (first_part) {
printf("MPY: can't mount SD card\n");
return false;
} else {
return true;
}
}
#endif
#if !MICROPY_HW_USES_BOOTLOADER
STATIC uint update_reset_mode(uint reset_mode) {
#if MICROPY_HW_HAS_SWITCH
if (switch_get()) {
// The original method used on the pyboard is appropriate if you have 2
// or more LEDs.
#if defined(MICROPY_HW_LED2)
for (uint i = 0; i < 3000; i++) {
if (!switch_get()) {
break;
}
mp_hal_delay_ms(20);
if (i % 30 == 29) {
if (++reset_mode > 3) {
reset_mode = 1;
}
led_state(2, reset_mode & 1);
led_state(3, reset_mode & 2);
led_state(4, reset_mode & 4);
}
}
// flash the selected reset mode
for (uint i = 0; i < 6; i++) {
led_state(2, 0);
led_state(3, 0);
led_state(4, 0);
mp_hal_delay_ms(50);
led_state(2, reset_mode & 1);
led_state(3, reset_mode & 2);
led_state(4, reset_mode & 4);
mp_hal_delay_ms(50);
}
mp_hal_delay_ms(400);
#elif defined(MICROPY_HW_LED1)
// For boards with only a single LED, we'll flash that LED the
// appropriate number of times, with a pause between each one
for (uint i = 0; i < 10; i++) {
led_state(1, 0);
for (uint j = 0; j < reset_mode; j++) {
if (!switch_get()) {
break;
}
led_state(1, 1);
mp_hal_delay_ms(100);
led_state(1, 0);
mp_hal_delay_ms(200);
}
mp_hal_delay_ms(400);
if (!switch_get()) {
break;
}
if (++reset_mode > 3) {
reset_mode = 1;
}
}
// Flash the selected reset mode
for (uint i = 0; i < 2; i++) {
for (uint j = 0; j < reset_mode; j++) {
led_state(1, 1);
mp_hal_delay_ms(100);
led_state(1, 0);
mp_hal_delay_ms(200);
}
mp_hal_delay_ms(400);
}
#else
#error Need a reset mode update method
#endif
}
#endif
return reset_mode;
}
#endif
void stm32_main(uint32_t reset_mode) {
#if !defined(STM32F0) && defined(MICROPY_HW_VTOR)
// Change IRQ vector table if configured differently
SCB->VTOR = MICROPY_HW_VTOR;
#endif
// Enable 8-byte stack alignment for IRQ handlers, in accord with EABI
SCB->CCR |= SCB_CCR_STKALIGN_Msk;
// Check if bootloader should be entered instead of main application
powerctrl_check_enter_bootloader();
// Enable caches and prefetch buffers
#if defined(STM32F4)
#if INSTRUCTION_CACHE_ENABLE
__HAL_FLASH_INSTRUCTION_CACHE_ENABLE();
#endif
#if DATA_CACHE_ENABLE
__HAL_FLASH_DATA_CACHE_ENABLE();
#endif
#if PREFETCH_ENABLE
__HAL_FLASH_PREFETCH_BUFFER_ENABLE();
#endif
#elif defined(STM32F7) || defined(STM32H7)
#if ART_ACCLERATOR_ENABLE
__HAL_FLASH_ART_ENABLE();
#endif
SCB_EnableICache();
SCB_EnableDCache();
#elif defined(STM32L4)
#if !INSTRUCTION_CACHE_ENABLE
__HAL_FLASH_INSTRUCTION_CACHE_DISABLE();
#endif
#if !DATA_CACHE_ENABLE
__HAL_FLASH_DATA_CACHE_DISABLE();
#endif
#if PREFETCH_ENABLE
__HAL_FLASH_PREFETCH_BUFFER_ENABLE();
#endif
#endif
mpu_init();
#if __CORTEX_M >= 0x03
// Set the priority grouping
NVIC_SetPriorityGrouping(NVIC_PRIORITYGROUP_4);
#endif
// SysTick is needed by HAL_RCC_ClockConfig (called in SystemClock_Config)
HAL_InitTick(TICK_INT_PRIORITY);
// set the system clock to be HSE
SystemClock_Config();
// enable GPIO clocks
__HAL_RCC_GPIOA_CLK_ENABLE();
__HAL_RCC_GPIOB_CLK_ENABLE();
__HAL_RCC_GPIOC_CLK_ENABLE();
#if defined(GPIOD)
__HAL_RCC_GPIOD_CLK_ENABLE();
#endif
#if defined(STM32F4) || defined(STM32F7)
#if defined(__HAL_RCC_DTCMRAMEN_CLK_ENABLE)
// The STM32F746 doesn't really have CCM memory, but it does have DTCM,
// which behaves more or less like normal SRAM.
__HAL_RCC_DTCMRAMEN_CLK_ENABLE();
#elif defined(CCMDATARAM_BASE)
// enable the CCM RAM
__HAL_RCC_CCMDATARAMEN_CLK_ENABLE();
#endif
#elif defined(STM32H7)
// Enable D2 SRAM1/2/3 clocks.
__HAL_RCC_D2SRAM1_CLK_ENABLE();
__HAL_RCC_D2SRAM2_CLK_ENABLE();
__HAL_RCC_D2SRAM3_CLK_ENABLE();
#endif
#if defined(MICROPY_BOARD_EARLY_INIT)
MICROPY_BOARD_EARLY_INIT();
#endif
// basic sub-system init
#if defined(STM32WB)
rfcore_init();
#endif
#if MICROPY_HW_SDRAM_SIZE
sdram_init();
#if MICROPY_HW_SDRAM_STARTUP_TEST
sdram_test(true);
#endif
#endif
#if MICROPY_PY_THREAD
pyb_thread_init(&pyb_thread_main);
#endif
pendsv_init();
led_init();
#if MICROPY_HW_HAS_SWITCH
switch_init0();
#endif
machine_init();
#if MICROPY_HW_ENABLE_RTC
rtc_init_start(false);
#endif
uart_init0();
spi_init0();
#if MICROPY_PY_PYB_LEGACY && MICROPY_HW_ENABLE_HW_I2C
i2c_init0();
#endif
#if MICROPY_HW_ENABLE_SDCARD
sdcard_init();
#endif
#if MICROPY_HW_ENABLE_STORAGE
storage_init();
#endif
#if MICROPY_PY_LWIP
// lwIP doesn't allow to reinitialise itself by subsequent calls to this function
// because the system timeout list (next_timeout) is only ever reset by BSS clearing.
// So for now we only init the lwIP stack once on power-up.
lwip_init();
#if LWIP_MDNS_RESPONDER
mdns_resp_init();
#endif
systick_enable_dispatch(SYSTICK_DISPATCH_LWIP, mod_network_lwip_poll_wrapper);
#endif
#if MICROPY_BLUETOOTH_NIMBLE
extern void mod_bluetooth_nimble_poll_wrapper(uint32_t ticks_ms);
systick_enable_dispatch(SYSTICK_DISPATCH_NIMBLE, mod_bluetooth_nimble_poll_wrapper);
#endif
#if MICROPY_PY_NETWORK_CYW43
{
cyw43_init(&cyw43_state);
uint8_t buf[8];
memcpy(&buf[0], "PYBD", 4);
mp_hal_get_mac_ascii(MP_HAL_MAC_WLAN0, 8, 4, (char*)&buf[4]);
cyw43_wifi_ap_set_ssid(&cyw43_state, 8, buf);
cyw43_wifi_ap_set_password(&cyw43_state, 8, (const uint8_t*)"pybd0123");
}
#endif
#if defined(MICROPY_HW_UART_REPL)
// Set up a UART REPL using a statically allocated object
pyb_uart_repl_obj.base.type = &pyb_uart_type;
pyb_uart_repl_obj.uart_id = MICROPY_HW_UART_REPL;
pyb_uart_repl_obj.is_static = true;
pyb_uart_repl_obj.timeout = 0;
pyb_uart_repl_obj.timeout_char = 2;
uart_init(&pyb_uart_repl_obj, MICROPY_HW_UART_REPL_BAUD, UART_WORDLENGTH_8B, UART_PARITY_NONE, UART_STOPBITS_1, 0);
uart_set_rxbuf(&pyb_uart_repl_obj, sizeof(pyb_uart_repl_rxbuf), pyb_uart_repl_rxbuf);
uart_attach_to_repl(&pyb_uart_repl_obj, true);
MP_STATE_PORT(pyb_uart_obj_all)[MICROPY_HW_UART_REPL - 1] = &pyb_uart_repl_obj;
#endif
soft_reset:
#if defined(MICROPY_HW_LED2)
led_state(1, 0);
led_state(2, 1);
#else
led_state(1, 1);
led_state(2, 0);
#endif
led_state(3, 0);
led_state(4, 0);
#if !MICROPY_HW_USES_BOOTLOADER
// check if user switch held to select the reset mode
reset_mode = update_reset_mode(1);
#endif
// Python threading init
#if MICROPY_PY_THREAD
mp_thread_init();
#endif
// Stack limit should be less than real stack size, so we have a chance
// to recover from limit hit. (Limit is measured in bytes.)
// Note: stack control relies on main thread being initialised above
mp_stack_set_top(&_estack);
mp_stack_set_limit((char*)&_estack - (char*)&_sstack - 1024);
// GC init
gc_init(MICROPY_HEAP_START, MICROPY_HEAP_END);
#if MICROPY_ENABLE_PYSTACK
static mp_obj_t pystack[384];
mp_pystack_init(pystack, &pystack[384]);
#endif
// MicroPython init
mp_init();
mp_obj_list_init(MP_OBJ_TO_PTR(mp_sys_path), 0);
mp_obj_list_append(mp_sys_path, MP_OBJ_NEW_QSTR(MP_QSTR_)); // current dir (or base dir of the script)
mp_obj_list_init(MP_OBJ_TO_PTR(mp_sys_argv), 0);
// Initialise low-level sub-systems. Here we need to very basic things like
// zeroing out memory and resetting any of the sub-systems. Following this
// we can run Python scripts (eg boot.py), but anything that is configurable
// by boot.py must be set after boot.py is run.
#if defined(MICROPY_HW_UART_REPL)
MP_STATE_PORT(pyb_stdio_uart) = &pyb_uart_repl_obj;
#else
MP_STATE_PORT(pyb_stdio_uart) = NULL;
#endif
readline_init0();
pin_init0();
extint_init0();
timer_init0();
#if MICROPY_HW_ENABLE_CAN
can_init0();
#endif
#if MICROPY_HW_ENABLE_USB
pyb_usb_init0();
#endif
// Initialise the local flash filesystem.
// Create it if needed, mount in on /flash, and set it as current dir.
bool mounted_flash = false;
#if MICROPY_HW_ENABLE_STORAGE
mounted_flash = init_flash_fs(reset_mode);
#endif
bool mounted_sdcard = false;
#if MICROPY_HW_SDCARD_MOUNT_AT_BOOT
// if an SD card is present then mount it on /sd/
if (sdcard_is_present()) {
// if there is a file in the flash called "SKIPSD", then we don't mount the SD card
if (!mounted_flash || f_stat(&fs_user_mount_flash.fatfs, "/SKIPSD", NULL) != FR_OK) {
mounted_sdcard = init_sdcard_fs();
}
}
#endif
#if MICROPY_HW_ENABLE_USB
// if the SD card isn't used as the USB MSC medium then use the internal flash
if (pyb_usb_storage_medium == PYB_USB_STORAGE_MEDIUM_NONE) {
pyb_usb_storage_medium = PYB_USB_STORAGE_MEDIUM_FLASH;
}
#endif
// set sys.path based on mounted filesystems (/sd is first so it can override /flash)
if (mounted_sdcard) {
mp_obj_list_append(mp_sys_path, MP_OBJ_NEW_QSTR(MP_QSTR__slash_sd));
mp_obj_list_append(mp_sys_path, MP_OBJ_NEW_QSTR(MP_QSTR__slash_sd_slash_lib));
}
if (mounted_flash) {
mp_obj_list_append(mp_sys_path, MP_OBJ_NEW_QSTR(MP_QSTR__slash_flash));
mp_obj_list_append(mp_sys_path, MP_OBJ_NEW_QSTR(MP_QSTR__slash_flash_slash_lib));
}
// reset config variables; they should be set by boot.py
MP_STATE_PORT(pyb_config_main) = MP_OBJ_NULL;
// run boot.py, if it exists
// TODO perhaps have pyb.reboot([bootpy]) function to soft-reboot and execute custom boot.py
if (reset_mode == 1 || reset_mode == 3) {
const char *boot_py = "boot.py";
int ret = pyexec_file_if_exists(boot_py);
if (ret & PYEXEC_FORCED_EXIT) {
goto soft_reset_exit;
}
if (!ret) {
flash_error(4);
}
}
// turn boot-up LEDs off
#if !defined(MICROPY_HW_LED2)
// If there is only one LED on the board then it's used to signal boot-up
// and so we turn it off here. Otherwise LED(1) is used to indicate dirty
// flash cache and so we shouldn't change its state.
led_state(1, 0);
#endif
led_state(2, 0);
led_state(3, 0);
led_state(4, 0);
// Now we initialise sub-systems that need configuration from boot.py,
// or whose initialisation can be safely deferred until after running
// boot.py.
#if MICROPY_HW_ENABLE_USB
// init USB device to default setting if it was not already configured
if (!(pyb_usb_flags & PYB_USB_FLAG_USB_MODE_CALLED)) {
#if MICROPY_HW_USB_MSC
const uint16_t pid = USBD_PID_CDC_MSC;
const uint8_t mode = USBD_MODE_CDC_MSC;
#else
const uint16_t pid = USBD_PID_CDC;
const uint8_t mode = USBD_MODE_CDC;
#endif
pyb_usb_dev_init(pyb_usb_dev_detect(), USBD_VID, pid, mode, 0, NULL, NULL);
}
#endif
#if MICROPY_HW_HAS_MMA7660
// MMA accel: init and reset
accel_init();
#endif
#if MICROPY_HW_ENABLE_SERVO
servo_init();
#endif
#if MICROPY_PY_NETWORK
mod_network_init();
#endif
// At this point everything is fully configured and initialised.
// Run the main script from the current directory.
if ((reset_mode == 1 || reset_mode == 3) && pyexec_mode_kind == PYEXEC_MODE_FRIENDLY_REPL) {
const char *main_py;
if (MP_STATE_PORT(pyb_config_main) == MP_OBJ_NULL) {
main_py = "main.py";
} else {
main_py = mp_obj_str_get_str(MP_STATE_PORT(pyb_config_main));
}
int ret = pyexec_file_if_exists(main_py);
if (ret & PYEXEC_FORCED_EXIT) {
goto soft_reset_exit;
}
if (!ret) {
flash_error(3);
}
}
#if MICROPY_ENABLE_COMPILER
// Main script is finished, so now go into REPL mode.
// The REPL mode can change, or it can request a soft reset.
for (;;) {
if (pyexec_mode_kind == PYEXEC_MODE_RAW_REPL) {
if (pyexec_raw_repl() != 0) {
break;
}
} else {
if (pyexec_friendly_repl() != 0) {
break;
}
}
}
#endif
soft_reset_exit:
// soft reset
#if MICROPY_HW_ENABLE_STORAGE
printf("MPY: sync filesystems\n");
storage_flush();
#endif
printf("MPY: soft reboot\n");
#if MICROPY_BLUETOOTH_NIMBLE
mp_bluetooth_deinit();
#endif
#if MICROPY_PY_NETWORK
mod_network_deinit();
#endif
soft_timer_deinit();
timer_deinit();
uart_deinit_all();
#if MICROPY_HW_ENABLE_CAN
can_deinit_all();
#endif
machine_deinit();
#if MICROPY_PY_THREAD
pyb_thread_deinit();
#endif
gc_sweep_all();
goto soft_reset;
}