# # For a description of the syntax of this configuration file, # see the file kconfig-language.txt in the NuttX tools repository. # if ARCH_BOARD_ESP32CORE choice prompt "On-board Crystal Frequency" default ESP32CORE_XTAL_40MZ config ESP32CORE_XTAL_40MZ bool "40MHz" config ESP32CORE_XTAL_26MHz bool "26MHz" endchoice # On-board Crystal Frequency config ESP32CORE_RUN_IRAM bool "Run from IRAM" default n ---help--- The default configuration is set up run from IRAM. However, the current (2016-11-14) OpenOCD for ESP32 does not support writing to FLASH. This option sets up the linker scripts to support execution from IRAM. In this case, OpenOCD can be used to load directly into IRAM. At this stage the nuttx image is small enough to be entirely memory- resident. Once board support is more mature you can add flash cache mapping code to run from SPI flash after initial boot. There are at least two possible approaches you could take: You can add the flash cache mapping code into nuttx directly, so it is self-contained - early nuttx initialization runs from IRAM and enables flash cache, and then off you go. Or you can use the esp-idf software bootloader and partition table scheme and have nuttx be an esp-idf "app" which allows interoperability with the esp-idf system but makes you reliant on the esp-idf design for these parts. Both are possible. endif # ARCH_BOARD_ESP32CORE