Add some information and disclaimers to the README

README.md

@@ -1 +1,32 @@
 # esp-hal
+
+An _extremely_ experimental attempt at writing a HAL which targets the **ESP32**, **ESP32-C3**, **ESP32-S2**, and **ESP32-S3**.
+
+**This should not be used for anything at this point in time. This is merely a proof-of-concept.**
+
+The various packages in this repository may or may not build at any given time.
+
+## What is working?
+
+For the **ESP32** and **ESP32-C3**, the `TIMG` and `UART` peripherals have (probably incomplete) implementations which are functional. These packages include examples to demonstrate this.
+
+The **ESP32-C3** has functioning `GPIO` as well, though the implementation may not be complete or correct.
+
+## What is NOT working?
+
+Everything else.
+
+## License
+
+Licensed under either of:
+
+- Apache License, Version 2.0 ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
+- MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
+
+at your option.
+
+### Contribution
+
+Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in
+the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without
+any additional terms or conditions.