esp-idf/components/esp_psram/Kconfig.spiram.common

# Common (non-chip-specific) SPIRAM options
#
# sourced into the "SPIRAM config" submenu for a specific chip.

config SPIRAM_BOOT_HW_INIT
    bool "Initialise the PSRAM related hardware"
    depends on SPIRAM
    default "y" if SPIRAM
    help
        If this is enabled, the PSRAM hardware will be initialized during startup.
        Enabling this config does not ensure make sure the availability of the PSRAM for usage,
        but just initialises the PSRAM hardware.
        This is necessary to configure PSRAM memory protection during the boot up.

config SPIRAM_BOOT_INIT
    bool "Initialize PSRAM during startup, including the hardware and memory related configurations"
    default "y"
    depends on SPIRAM_BOOT_HW_INIT
    help
        If this is enabled, the PSRAM will be enabled during initial boot. Unless you
        have specific requirements, you'll want to leave this enabled so memory allocated
        during boot-up can also be placed in PSRAM.

config SPIRAM_PRE_CONFIGURE_MEMORY_PROTECTION
    bool "Pre-configure memory protection for PSRAM"
    default y if SPIRAM_BOOT_INIT
    default n
    depends on SPIRAM
    help
        If this is enabled, the PSRAM will be pre-configured for memory protection during initial boot.
        This configuration takes into consideration the PSRAM memory configurations that are performed
        by ESP-IDF's default PSRAM initialization function, esp_psram_init().
        Thus, the config is enabled by default when SPIRAM_BOOT_INIT is enabled,
        because the function esp_psram_init() would be called in the startup code.

        In case you wish to disable SPIRAM_BOOT_INIT just for delaying the PSRAM initialization and plan
        to use the ESP-IDF's default PSRAM initialization function, esp_psram_init() in the application code,
        you should still enable this config to enable memory protection for the PSRAM.

        Note that enabling this config also considers that the rest of the PSRAM memory that is left after
        the memory configurations are performed by esp_psram_init(), can be allocated to the heap using the function
        esp_psram_extram_add_to_heap_allocator(), thus configures this region with heap memory protection (RW).

        As an advanced usage, if you plan to initialize the PSRAM memory regions manually by yourself without
        using the function esp_psram_init(), you should disable this config to avoid any memory protection and
        usage conflicts.

config SPIRAM_IGNORE_NOTFOUND
    bool "Ignore PSRAM when not found"
    default "n"
    depends on SPIRAM_BOOT_HW_INIT && !SPIRAM_ALLOW_BSS_SEG_EXTERNAL_MEMORY && !SPIRAM_ALLOW_NOINIT_SEG_EXTERNAL_MEMORY
    help
        Normally, if psram initialization is enabled during compile time but not found at runtime, it
        is seen as an error making the CPU panic. If this is enabled, booting will complete
        but no PSRAM will be available. In particular, it is important to note that when SPIRAM_IGNORE_NOTFOUND
        is enabled, some WIFI related configs will be set to the default value used when SPIRAM is disabled.
        It can be assumed that by enabling this config, WIFI and LWIP will assume that the current chip does not
        have SPIRAM. SPIRAM_TRY_ALLOCATE_WIFI_LWIP will not work, buffers in WIFI and LWIP will be set to smaller
        ranges and default values. WIFI_CACHE_TX_BUFFER_NUM and ESP_WIFI_AMSDU_TX_ENABLED will be disabled,
        ESP_WIFI_TX_BUFFER will be set to ESP_WIFI_DYNAMIC_TX_BUFFER.

choice SPIRAM_USE
    prompt "SPI RAM access method"
    default SPIRAM_USE_MALLOC
    help
        The SPI RAM can be accessed in multiple methods: by just having it available as an unmanaged
        memory region in the CPU's memory map, by integrating it in the heap as 'special' memory
        needing heap_caps_malloc to allocate, or by fully integrating it making malloc() also able to
        return SPI RAM pointers.

    config SPIRAM_USE_MEMMAP
        bool "Integrate RAM into memory map"
    config SPIRAM_USE_CAPS_ALLOC
        bool "Make RAM allocatable using heap_caps_malloc(..., MALLOC_CAP_SPIRAM)"
    config SPIRAM_USE_MALLOC
        bool "Make RAM allocatable using malloc() as well"
        select FREERTOS_SUPPORT_STATIC_ALLOCATION
endchoice

config SPIRAM_MEMTEST
    bool "Run memory test on SPI RAM initialization"
    default "y"
    depends on SPIRAM_BOOT_INIT
    help
        Runs a rudimentary memory test on initialization. Aborts when memory test fails. Disable this for
        slightly faster startup.

config SPIRAM_MALLOC_ALWAYSINTERNAL
    int "Maximum malloc() size, in bytes, to always put in internal memory"
    depends on SPIRAM_USE_MALLOC
    default 16384
    range 0 131072
    help
        If malloc() is capable of also allocating SPI-connected ram, its allocation strategy will prefer to
        allocate chunks less than this size in internal memory, while allocations larger than this will be
        done from external RAM. If allocation from the preferred region fails, an attempt is made to allocate
        from the non-preferred region instead, so malloc() will not suddenly fail when either internal or
        external memory is full.

config SPIRAM_TRY_ALLOCATE_WIFI_LWIP
    bool "Try to allocate memories of WiFi and LWIP in SPIRAM firstly. If failed, allocate internal memory"
    depends on SPIRAM_USE_CAPS_ALLOC || SPIRAM_USE_MALLOC
    default "n"
    help
        Try to allocate memories of WiFi and LWIP in SPIRAM firstly. If failed, try to allocate internal
        memory then.

config SPIRAM_MALLOC_RESERVE_INTERNAL
    int "Reserve this amount of bytes for data that specifically needs to be in DMA or internal memory"
    depends on SPIRAM_USE_MALLOC
    default 32768
    range 0 262144
    help
        Because the external/internal RAM allocation strategy is not always perfect, it sometimes may happen
        that the internal memory is entirely filled up. This causes allocations that are specifically done in
        internal memory, for example the stack for new tasks or memory to service DMA or have memory that's
        also available when SPI cache is down, to fail. This option reserves a pool specifically for requests
        like that; the memory in this pool is not given out when a normal malloc() is called.

        Set this to 0 to disable this feature.

        Note that because FreeRTOS stacks are forced to internal memory, they will also use this memory pool;
        be sure to keep this in mind when adjusting this value.

        Note also that the DMA reserved pool may not be one single contiguous memory region, depending on the
        configured size and the static memory usage of the app.

config SPIRAM_ALLOW_BSS_SEG_EXTERNAL_MEMORY
    bool "Allow .bss segment placed in external memory"
    default n
    depends on SPIRAM
    select ESP_ALLOW_BSS_SEG_EXTERNAL_MEMORY
    help
        If enabled, variables with EXT_RAM_BSS_ATTR attribute will be placed in SPIRAM instead of internal DRAM.
        BSS section of `lwip`, `net80211`, `pp`, `bt` libraries will be automatically placed
        in SPIRAM. BSS sections from other object files and libraries can also be placed in SPIRAM through
        linker fragment scheme `extram_bss`.

        Note that the variables placed in SPIRAM using EXT_RAM_BSS_ATTR will be zero initialized.

config SPIRAM_ALLOW_NOINIT_SEG_EXTERNAL_MEMORY
    bool "Allow .noinit segment placed in external memory"
    default n
    depends on SPIRAM
    help
        If enabled, noinit variables can be placed in PSRAM using EXT_RAM_NOINIT_ATTR.

        Note the values placed into this section will not be initialized at startup and should keep its value
        after software restart.