RIOT-OS uses part of Espressif ESP8266 RTOS SDK to build support for
this CPU. The SDK includes some vendor-provided closed source
pre-compiled libraries that we need to modify to adapt to RIOT-OS
usage. This library modifications was done once and uploaded to a fork
of the vendor repository and was provided as an environment variable.
This patch changes two things:
1. It installs the SDK as a RIOT PKG from the new pkg/esp8266_sdk
directory instead of requiring the user to download it separately.
2. It performs the library modifications (symbol renames) on the pkg
Makefile removing the need to use a fork with the modifications applied
and simplifying the SDK update and future modifications.
This change sets the SDK package version (git SHA) to the same one that
our fork was using as a parent in the vendor repository, meaning that
the output libraries are exactly the same as before.
Tested with
```
ESP8266_RTOS_SDK_DIR=/dev/null USEMODULE=esp_log_startup make -C tests/shell BOARD=esp8266-esp-12x flash
```
and verified that the program works. The boot message now includes:
```
ESP8266-RTOS-SDK Version v3.1-51-g913a06a9
```
confirming the SDK version used.
`/dev/null` in the test is just to make sure that no evaluation of
`ESP8266_RTOS_SDK_DIR` in make is affected by the environment variable
value which would be set to the SDK for people who followed the set up
instructions before this change.
Tested the checkout size:
```bash
$ du -hs build/pkg/esp8266_sdk/
124M build/pkg/esp8266_sdk/
```
This is an implementation of the ESP32 SoftAP mode using the
`esp_wifi_ap` pseudomodule.
Signed-off-by: Jean Pierre Dudey <jeandudey@hotmail.com>
Co-authored-by: Gunar Schorcht <gunar@schorcht.net>
To control the log level and the format of the log output of SDK libraries, a bunch of library-specific printf functions are realized which map the log output from SDK libraries to RIOT's log macros.
The modified version esptool.py from RTOS SDK that is required for flashing an image, is now placed in `dist/tools/esptool.py` and used directly from there. The advantage is that `esptool.py` hasn't to be installed explicitly anymore. Having RIOT is enough. The documentation is adapted accordingly. The oly prerequisite is that python and the pyserial module are installed.
To make the migration progress to the new RTOS SDK easier, the new toolchain was renamed to xtensa-esp8266-elf. This makes it possible to have the new and the old toolchain installed in parallel.
The documentation had to be changed due to the relation of module `esp_now` to `esp_wifi` module. In addition, a number of corrections have been made. In the case of documentation, it is impossible to do this in various commits.
