Merge pull request adafruit#9554 from samblenny/espressif-build-docs

Make Building CircuitPython guide easier to find

Author: dhalbert

CONTRIBUTING.md

@@ -28,11 +28,21 @@ As CircuitPython grows, there are more and more ways to contribute. Here are som
 * Contribute Python code to CircuitPython libraries that support new devices or features of an existing device.
 * Contribute C code to CircuitPython which fixes an open issue or adds a new feature.
 
-## Getting started with C
-CircuitPython developer Dan Halbert (@dhalbert) has written up build instructions using native build
-tools [here](https://learn.adafruit.com/building-circuitpython).
+## Building CircuitPython: Getting started with C
 
-For SAMD21 debugging workflow tips check out [this learn guide](https://learn.adafruit.com/debugging-the-samd21-with-gdb) from Scott (@tannewt).
+The CircuitPython core is implemented mostly in C. If you want to add support
+for new boards, add features to the core, fix bugs in the core, or compile with
+special options (perhaps to make a debug build with UART logging), you will
+need to install a development environment with build tools.
+
+Build Documentation:
+
+- [Building CircuitPython Learn Guide](https://learn.adafruit.com/building-circuitpython):
+  CircuitPython developer Dan Halbert (@dhalbert) wrote this guide with build
+  instructions for using native build tools. **This is the primary getting
+  started documentation for building CircuitPython.**
+
+- For SAMD21 debugging workflow tips check out [this learn guide](https://learn.adafruit.com/debugging-the-samd21-with-gdb) from Scott (@tannewt).
 
 ## Developer contacts
 Scott Shawcroft ([@tannewt](https://github.com/tannewt)) is the lead developer of CircuitPython

ports/espressif/README.rst

@@ -155,6 +155,8 @@ Before building or flashing the, you must `install the ESP-IDF <https://docs.esp
 
 Note: This must be re-done every time the ESP-IDF is updated, but not every time you build.
 
+Note: The ``./esp-idf/install.sh`` script is part of a submodule. Please refer to the `Building CircuitPython Learn Guide <https://learn.adafruit.com/building-circuitpython>`_ for instructions about using ``make fetch-port-submodules``.
+
 Run ``cd ports/espressif`` from ``circuitpython/`` to move to the espressif port root, and run:
 
 .. code-block::