This commit adds several small items to improve the support for OTA
updates on an esp32:
- a partition table for 4MB flash modules that has two OTA partitions ready
to go to do updates
- a GENERIC_OTA board that uses that partition table and that enables
automatic roll-back in the bootloader
- a new esp32.Partition.mark_app_valid_cancel_rollback() class-method to
signal that the boot is successful and should not be rolled back at the
next reset
- an automated test for doing an OTA update
- documentation updates
This commit consolidates a number of check_esp_err functions that check
whether an ESP-IDF return code is OK and raises an exception if not. The
exception raised is an OSError with the error code as the first argument
(negative if it's ESP-IDF specific) and the ESP-IDF error string as the
second argument.
This commit also fixes esp32.Partition.set_boot to use check_esp_err, and
uses that function for a unit test.
Damien George
Thorsten von Eicken
Damien George