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

endmenu  # ESP System Settings