esp-idf/components/esptool_py/flasher_args.json.in

{
    "write_flash_args" : [ "--flash_mode", "${ESPFLASHMODE}",
                           "--flash_size", "${ESPFLASHSIZE}",
                           "--flash_freq", "${ESPFLASHFREQ}" ],
    "flash_settings" : {
        "flash_mode": "${ESPFLASHMODE}",
        "flash_size": "${ESPFLASHSIZE}",
        "flash_freq": "${ESPFLASHFREQ}"
    },
    "flash_files" : {
        $<JOIN:${FLASH_PROJECT_ARGS_JSON},,
        >
    },
    $<JOIN:${FLASH_PROJECT_ARGS_ENTRY_JSON},,
    >,
    "extra_esptool_args" : {
        "after"  : "${ESPTOOLPY_AFTER}",
        "before" : "${ESPTOOLPY_BEFORE}"
    }
}