esp-idf/components/esp_system/Kconfig

menu "ESP System Settings"

    choice ESP_SYSTEM_PANIC
        prompt "Panic handler behaviour"
        default ESP_SYSTEM_PANIC_PRINT_REBOOT
        help
            If FreeRTOS detects unexpected behaviour or an unhandled exception, the panic handler is
            invoked. Configure the panic handler's action here.

        config ESP_SYSTEM_PANIC_PRINT_HALT
            bool "Print registers and halt"
            help
                Outputs the relevant registers over the serial port and halt the
                processor. Needs a manual reset to restart.

        config ESP_SYSTEM_PANIC_PRINT_REBOOT
            bool "Print registers and reboot"
            help
                Outputs the relevant registers over the serial port and immediately
                reset the processor.

        config ESP_SYSTEM_PANIC_SILENT_REBOOT
            bool "Silent reboot"
            help
                Just resets the processor without outputting anything

        config ESP_SYSTEM_PANIC_GDBSTUB
            bool "Invoke GDBStub"
            select ESP_GDBSTUB_ENABLED
            help
                Invoke gdbstub on the serial port, allowing for gdb to attach to it to do a postmortem
                of the crash.
    endchoice

    config ESP_SYSTEM_SINGLE_CORE_MODE
        bool
        default n
        help
            Only initialize and use the main core.

    config ESP_SYSTEM_RTC_EXT_XTAL
        # This is a High Layer Kconfig option, invisible, can be selected by other Kconfig option
        # e.g. It will be selected on when ESP32_RTC_CLK_SRC_EXT_CRYS is on
        bool
        default n

    config ESP_SYSTEM_RTC_EXT_XTAL_BOOTSTRAP_CYCLES
        int "Bootstrap cycles for external 32kHz crystal"
        depends on ESP_SYSTEM_RTC_EXT_XTAL
        default 5 if IDF_TARGET_ESP32
        default 0
        range 0 32768
        help
            To reduce the startup time of an external RTC crystal,
            we bootstrap it with a 32kHz square wave for a fixed number of cycles.
            Setting 0 will disable bootstrapping (if disabled, the crystal may take
            longer to start up or fail to oscillate under some conditions).

            If this value is too high, a faulty crystal may initially start and then fail.
            If this value is too low, an otherwise good crystal may not start.

            To accurately determine if the crystal has started,
            set a larger "Number of cycles for RTC_SLOW_CLK calibration" (about 3000).

    config ESP_SYSTEM_RTC_FAST_MEM_AS_HEAP_DEPCHECK
        bool
        default y if IDF_TARGET_ESP32 && FREERTOS_UNICORE
        default y if IDF_TARGET_ESP32S2
        default y if IDF_TARGET_ESP32C3
        default y if IDF_TARGET_ESP32S3

    config ESP_SYSTEM_ALLOW_RTC_FAST_MEM_AS_HEAP
        bool "Enable RTC fast memory for dynamic allocations"
        default y if IDF_TARGET_ESP32
        default y if IDF_TARGET_ESP32S2
        default y if IDF_TARGET_ESP32C3
        default n if IDF_TARGET_ESP32S3  # TODO
        depends on ESP_SYSTEM_RTC_FAST_MEM_AS_HEAP_DEPCHECK
        help
            This config option allows to add RTC fast memory region to system heap with capability
            similar to that of DRAM region but without DMA. This memory will be consumed first per
            heap initialization order by early startup services and scheduler related code. Speed
            wise RTC fast memory operates on APB clock and hence does not have much performance impact.

    config ESP_SYSTEM_PD_FLASH
        bool "PD flash at light sleep when there is no SPIRAM"
        depends on !SPIRAM
        default y
        help
            If enabled, chip will try to power down flash at light sleep, which costs more time when chip wakes up.
            Can only be enabled if there is no SPIRAM configured. This option will in fact consider VDD_SDIO auto power
            value (ESP_PD_OPTION_AUTO) as OFF. Also, it is possible to force a power domain to stay ON during light
            sleep by using esp_sleep_pd_config() function.

    config ESP_SYSTEM_PM_POWER_DOWN_CPU
        bool "Power down CPU in light sleep"
        depends on IDF_TARGET_ESP32C3
        default y
        help
            If enabled, the CPU will be powered down in light sleep. Enabling this option will consume
            1.68 KB of internal RAM and will reduce sleep current consumption by about 100 uA.

    menu "Memory protection"

        config ESP_SYSTEM_MEMPROT_FEATURE
            bool "Enable memory protection"
            depends on IDF_TARGET_ESP32C3 || IDF_TARGET_ESP32S2
            default "y"
            help
                If enabled, the permission control module watches all the memory access and fires the panic handler
                if a permission violation is detected. This feature automatically splits
                the SRAM memory into data and instruction segments and sets Read/Execute permissions
                for the instruction part (below given splitting address) and Read/Write permissions
                for the data part (above the splitting address). The memory protection is effective
                on all access through the IRAM0 and DRAM0 buses.

        config ESP_SYSTEM_MEMPROT_FEATURE_LOCK
            depends on ESP_SYSTEM_MEMPROT_FEATURE
            bool "Lock memory protection settings"
            default "y"
            help
                Once locked, memory protection settings cannot be changed anymore.
                The lock is reset only on the chip startup.

    endmenu  # Memory protection

    config ESP_SYSTEM_EVENT_QUEUE_SIZE
        int "System event queue size"
        default 32
        help
            Config system event queue size in different application.

    config ESP_SYSTEM_EVENT_TASK_STACK_SIZE
        int "Event loop task stack size"
        default 2304
        help
            Config system event task stack size in different application.

    config ESP_MAIN_TASK_STACK_SIZE
        int "Main task stack size"
        default 3584
        help
            Configure the "main task" stack size. This is the stack of the task
            which calls app_main(). If app_main() returns then this task is deleted
            and its stack memory is freed.

    choice ESP_MAIN_TASK_AFFINITY
        prompt "Main task core affinity"
        default ESP_MAIN_TASK_AFFINITY_CPU0
        help
            Configure the "main task" core affinity. This is the used core of the task
            which calls app_main(). If app_main() returns then this task is deleted.

        config ESP_MAIN_TASK_AFFINITY_CPU0
            bool "CPU0"
        config ESP_MAIN_TASK_AFFINITY_CPU1
            bool "CPU1"
            depends on !FREERTOS_UNICORE
        config ESP_MAIN_TASK_AFFINITY_NO_AFFINITY
            bool "No affinity"

    endchoice

    config ESP_MAIN_TASK_AFFINITY
        hex
        default 0x0 if ESP_MAIN_TASK_AFFINITY_CPU0
        default 0x1 if ESP_MAIN_TASK_AFFINITY_CPU1
        default FREERTOS_NO_AFFINITY if ESP_MAIN_TASK_AFFINITY_NO_AFFINITY

    config ESP_MINIMAL_SHARED_STACK_SIZE
        int "Minimal allowed size for shared stack"
        default 2048
        help
            Minimal value of size, in bytes, accepted to execute a expression
            with shared stack.

    choice ESP_CONSOLE_UART
        prompt "Channel for console output"
        default ESP_CONSOLE_UART_DEFAULT
        help
            Select where to send console output (through stdout and stderr).

            - Default is to use UART0 on pre-defined GPIOs.
            - If "Custom" is selected, UART0 or UART1 can be chosen,
              and any pins can be selected.
            - If "None" is selected, there will be no console output on any UART, except
              for initial output from ROM bootloader. This ROM output can be suppressed by
              GPIO strapping or EFUSE, refer to chip datasheet for details.
            - On chips with USB peripheral, "USB CDC" option redirects output to the
              CDC port. This option uses the CDC driver in the chip ROM.
              This option is incompatible with TinyUSB stack.
        config ESP_CONSOLE_UART_DEFAULT
            bool "Default: UART0"
        config ESP_CONSOLE_USB_CDC
            bool "USB CDC"
            # The naming is confusing: USB_ENABLED means that TinyUSB driver is enabled, not USB in general.
            # && !USB_ENABLED is because the ROM CDC driver is currently incompatible with TinyUSB.
            depends on (IDF_TARGET_ESP32S2 || IDF_TARGET_ESP32S3)  && !USB_ENABLED
        config ESP_CONSOLE_UART_CUSTOM
            bool "Custom UART"
        config ESP_CONSOLE_NONE
            bool "None"
    endchoice

    # Internal option, indicates that console UART is used (and not USB, for example)
    config ESP_CONSOLE_UART
        bool
        default y if ESP_CONSOLE_UART_DEFAULT || ESP_CONSOLE_UART_CUSTOM

    config ESP_CONSOLE_MULTIPLE_UART
        bool
        default y if !IDF_TARGET_ESP32C3

    choice ESP_CONSOLE_UART_NUM
        prompt "UART peripheral to use for console output (0-1)"
        depends on ESP_CONSOLE_UART_CUSTOM && ESP_CONSOLE_MULTIPLE_UART
        default ESP_CONSOLE_UART_CUSTOM_NUM_0
        help
            This UART peripheral is used for console output from the ESP-IDF Bootloader and the app.

            If the configuration is different in the Bootloader binary compared to the app binary, UART
            is reconfigured after the bootloader exits and the app starts.

            Due to an ESP32 ROM bug, UART2 is not supported for console output
            via esp_rom_printf.

        config ESP_CONSOLE_UART_CUSTOM_NUM_0
            bool "UART0"
        config ESP_CONSOLE_UART_CUSTOM_NUM_1
            bool "UART1"
    endchoice

    config ESP_CONSOLE_UART_NUM
        int
        default 0 if ESP_CONSOLE_UART_DEFAULT
        default 0 if !ESP_CONSOLE_MULTIPLE_UART
        default 0 if ESP_CONSOLE_UART_CUSTOM_NUM_0
        default 1 if ESP_CONSOLE_UART_CUSTOM_NUM_1
        default -1 if !ESP_CONSOLE_UART

    config ESP_CONSOLE_UART_TX_GPIO
        int "UART TX on GPIO#"
        depends on ESP_CONSOLE_UART_CUSTOM
        range 0 46
        default 1 if IDF_TARGET_ESP32
        default 21 if IDF_TARGET_ESP32C3
        default 43
        help
             This GPIO is used for console UART TX output in the ESP-IDF Bootloader and the app (including
             boot log output and default standard output and standard error of the app).

             If the configuration is different in the Bootloader binary compared to the app binary, UART
             is reconfigured after the bootloader exits and the app starts.

    config ESP_CONSOLE_UART_RX_GPIO
        int "UART RX on GPIO#"
        depends on ESP_CONSOLE_UART_CUSTOM
        range 0 46
        default 3 if IDF_TARGET_ESP32
        default 20 if IDF_TARGET_ESP32C3
        default 44
        help
            This GPIO is used for UART RX input in the ESP-IDF Bootloader and the app (including
            default default standard input of the app).

            Note: The default ESP-IDF Bootloader configures this pin but doesn't read anything from the UART.

            If the configuration is different in the Bootloader binary compared to the app binary, UART
            is reconfigured after the bootloader exits and the app starts.


    config ESP_CONSOLE_UART_BAUDRATE
        int
        prompt "UART console baud rate" if ESP_CONSOLE_UART_CUSTOM
        depends on ESP_CONSOLE_UART
        default 115200
        range 1200 4000000 if !PM_ENABLE
        range 1200 1000000 if PM_ENABLE
        help
            This baud rate is used by both the ESP-IDF Bootloader and the app (including
            boot log output and default standard input/output/error of the app).

            The app's maximum baud rate depends on the UART clock source. If Power Management is disabled,
            the UART clock source is the APB clock and all baud rates in the available range will be sufficiently
            accurate. If Power Management is enabled, REF_TICK clock source is used so the baud rate is divided
            from 1MHz. Baud rates above 1Mbps are not possible and values between 500Kbps and 1Mbps may not be
            accurate.

            If the configuration is different in the Bootloader binary compared to the app binary, UART
            is reconfigured after the bootloader exits and the app starts.

    config ESP_CONSOLE_USB_CDC_RX_BUF_SIZE
        int "Size of USB CDC RX buffer"
        depends on ESP_CONSOLE_USB_CDC
        default 64
        range 4 16384
        help
            Set the size of USB CDC RX buffer. Increase the buffer size if your application
            is often receiving data over USB CDC.

    config ESP_CONSOLE_USB_CDC_SUPPORT_ETS_PRINTF
        bool "Enable esp_rom_printf / ESP_EARLY_LOG via USB CDC"
        depends on ESP_CONSOLE_USB_CDC
        default n
        help
            If enabled, esp_rom_printf and ESP_EARLY_LOG output will also be sent over USB CDC.
            Disabling this option saves about 1kB or RAM.

    config ESP_INT_WDT
        bool "Interrupt watchdog"
        default y
        help
            This watchdog timer can detect if the FreeRTOS tick interrupt has not been called for a certain time,
            either because a task turned off interrupts and did not turn them on for a long time, or because an
            interrupt handler did not return. It will try to invoke the panic handler first and failing that
            reset the SoC.

    config ESP_INT_WDT_TIMEOUT_MS
        int "Interrupt watchdog timeout (ms)"
        depends on ESP_INT_WDT
        default 300 if !ESP32_SPIRAM_SUPPORT
        default 800 if ESP32_SPIRAM_SUPPORT
        range 10 10000
        help
            The timeout of the watchdog, in miliseconds. Make this higher than the FreeRTOS tick rate.

    config ESP_INT_WDT_CHECK_CPU1
        bool "Also watch CPU1 tick interrupt"
        depends on ESP_INT_WDT && !FREERTOS_UNICORE
        default y
        help
            Also detect if interrupts on CPU 1 are disabled for too long.

    config ESP_TASK_WDT
        bool "Initialize Task Watchdog Timer on startup"
        default y
        help
            The Task Watchdog Timer can be used to make sure individual tasks are still
            running. Enabling this option will cause the Task Watchdog Timer to be
            initialized automatically at startup. The Task Watchdog timer can be
            initialized after startup as well (see Task Watchdog Timer API Reference)

    config ESP_TASK_WDT_PANIC
        bool "Invoke panic handler on Task Watchdog timeout"
        depends on ESP_TASK_WDT
        default n
        help
            If this option is enabled, the Task Watchdog Timer will be configured to
            trigger the panic handler when it times out. This can also be configured
            at run time (see Task Watchdog Timer API Reference)

    config ESP_TASK_WDT_TIMEOUT_S
        int "Task Watchdog timeout period (seconds)"
        depends on ESP_TASK_WDT
        range 1 60
        default 5
        help
            Timeout period configuration for the Task Watchdog Timer in seconds.
            This is also configurable at run time (see Task Watchdog Timer API Reference)

    config ESP_TASK_WDT_CHECK_IDLE_TASK_CPU0
        bool "Watch CPU0 Idle Task"
        depends on ESP_TASK_WDT
        default y
        help
            If this option is enabled, the Task Watchdog Timer will watch the CPU0
            Idle Task. Having the Task Watchdog watch the Idle Task allows for detection
            of CPU starvation as the Idle Task not being called is usually a symptom of
            CPU starvation. Starvation of the Idle Task is detrimental as FreeRTOS household
            tasks depend on the Idle Task getting some runtime every now and then.

    config ESP_TASK_WDT_CHECK_IDLE_TASK_CPU1
        bool "Watch CPU1 Idle Task"
        depends on ESP_TASK_WDT && !FREERTOS_UNICORE
        default y
        help
            If this option is enabled, the Task Wtachdog Timer will wach the CPU1
            Idle Task.

    config ESP_IPC_TASK_STACK_SIZE
        int "Inter-Processor Call (IPC) task stack size"
        range 512 65536 if !APPTRACE_ENABLE
        range 2048 65536 if APPTRACE_ENABLE
        default 2048 if APPTRACE_ENABLE
        default 1024
        help
            Configure the IPC tasks stack size. One IPC task runs on each core
            (in dual core mode), and allows for cross-core function calls.

            See IPC documentation for more details.

            The default stack size should be enough for most common use cases.
            It can be shrunk if you are sure that you do not use any custom
            IPC functionality.

    config ESP_IPC_USES_CALLERS_PRIORITY
        bool "IPC runs at caller's priority"
        default y
        depends on !FREERTOS_UNICORE
        help
            If this option is not enabled then the IPC task will keep behavior
            same as prior to that of ESP-IDF v4.0, and hence IPC task will run
            at (configMAX_PRIORITIES - 1) priority.

    config ESP_PANIC_HANDLER_IRAM
        bool "Place panic handler code in IRAM"
        default n
        help
            If this option is disabled (default), the panic handler code is placed in flash not IRAM.
            This means that if ESP-IDF crashes while flash cache is disabled, the panic handler will
            automatically re-enable flash cache before running GDB Stub or Core Dump. This adds some minor
            risk, if the flash cache status is also corrupted during the crash.

            If this option is enabled, the panic handler code is placed in IRAM. This allows the panic
            handler to run without needing to re-enable cache first. This may be necessary to debug some
            complex issues with crashes while flash cache is disabled (for example, when writing to
            SPI flash.)

    config ESP_DEBUG_STUBS_ENABLE
        bool
        default COMPILER_OPTIMIZATION_LEVEL_DEBUG
        depends on !ESP32_TRAX && !ESP32S2_TRAX
        help
            Debug stubs are used by OpenOCD to execute pre-compiled onboard code
            which does some useful debugging stuff, e.g. GCOV data dump.


endmenu  # ESP System Settings