The Simple Boot feature for Espressif chips is a method of booting
that doesn't depend on a 2nd stage bootloader. Its not the
intention to replace a 2nd stage bootloader such as MCUboot and
ESP-IDF bootloader, but to have a minimal and straight-forward way
of booting, and also simplify the building.
This commit also removes deprecated code and makes this bootloader
configuration as default for esp32s3 targets and removes the need
for running 'make bootloader' command for it.
Other related fix, but not directly to Simple Boot:
- Instrumentation is required to run from IRAM to support it during
initialization. `is_eco0` function also needs to run from IRAM.
- `rtc.data` section placement was fixed.
- Provide arch-defined interfaces for efuses, in order to decouple
board config level from arch-defined values.
Signed-off-by: Almir Okato <almir.okato@espressif.com>
This config also prevents crashes due to the commit 6be363f, which
fix a race condition in multi-threaded write/read of the serial
driver, but increases stack size.
Almir Okato