Compiling the firmware for ESP32 with two board variants

[asherevan]

I am looking for a way to compile the ESP32 firmware with both the SPIRAM and the OTA BOARD_VARIANT.
Is there a way to do this?

[shariltumin]

Make a copy of ESP32_GENERIC

$ cd boards
$ cp -r ESP32_GENERIC ESP32_ASH

Edit sdconfig.ash

$ cd ESP32_ASH
$ vi sdconfig.ash

with these lines

# MicroPython on ESP32, ESP IDF configuration with SPIRAM support

CONFIG_SPIRAM=y
CONFIG_SPIRAM_CACHE_WORKAROUND=y
CONFIG_SPIRAM_IGNORE_NOTFOUND=y
CONFIG_SPIRAM_USE_MALLOC=y

# This is the threshold for preferring small allocations from internal memory
# first, before failing over to PSRAM.
CONFIG_SPIRAM_MALLOC_ALWAYSINTERNAL=8192

# SPIRAM increases the size of the firmware and overflows iram0_0_seg, due
# to PSRAM bug workarounds.  Apply some options to reduce the firmware size.
CONFIG_COMPILER_OPTIMIZATION_SIZE=y
CONFIG_COMPILER_OPTIMIZATION_CHECKS_SILENT=y
# CONFIG_RINGBUF_PLACE_FUNCTIONS_INTO_FLASH=y # Workaround required: see main_esp32/linker.lf
CONFIG_FREERTOS_PLACE_FUNCTIONS_INTO_FLASH=y
CONFIG_FREERTOS_PLACE_SNAPSHOT_FUNS_INTO_FLASH=y

# OTA
CONFIG_PARTITION_TABLE_CUSTOM=y
CONFIG_PARTITION_TABLE_CUSTOM_FILENAME="partitions-4MiB-ota.csv"

# Reduce firmware size to fit in the OTA partition.
CONFIG_COMPILER_OPTIMIZATION_SIZE=y
CONFIG_COMPILER_OPTIMIZATION_PERF=n
CONFIG_COMPILER_OPTIMIZATION_CHECKS_SILENT=y

Edit mpconfigboard.cmake

$ vi mpconfigboard.cmake

with these lines

set(IDF_TARGET esp32)

set(SDKCONFIG_DEFAULTS
    boards/sdkconfig.base
    ${SDKCONFIG_IDF_VERSION_SPECIFIC}
    ${MICROPY_BOARD_DIR}/sdkconfig.ash
    boards/sdkconfig.ble
)

set(MICROPY_FROZEN_MANIFEST ${MICROPY_BOARD_DIR}/manifest.py)

I like to have my manifest.py in the board directory. You can delate that line if you prefer to use the default.

With these in place, you can

$ cd ../../
$ make V=1 BOARD=ESP32_ASH

to build your firmware.