Add NixOS alternative for TockWorld.

This commit adds a NixOS VM alternative for Windows users or
user that don't want to follow the prerequisites. The text of
the workshop has been modified to reflect this addition.

Author: JADarius

docs/tock_workshop/index.md

@@ -2,16 +2,18 @@
 
 ## Prerequisites
 
+:::note Windows Users or participants that are willing to use a VM
+This workshop will not work on Windows systems.
+You can try following the guide using a Linux VM/WSL2,
+or you can use the NixOS VM we provide [here](https://drive.google.com/file/d/1-jOsuWdSnOlmyupMWb3Vw4oG_t77BnwQ/view?usp=sharing) (only works on VirtualBox).
+The username and password are both `ipwembedded`.
+If you will be using the NixOS VM, you can skip the prerequisites.
+:::
+
 ### Rust Toolchain
 
 You will need to install the Rust toolchain. To do so, you can follow the instructions on the [Getting started](https://www.rust-lang.org/learn/get-started) page of the Rust Language website.
 
-:::info Windows Install Tips
-If you are using Windows, you may be prompted to install [Visual Studio C++ Build tools](https://visualstudio.microsoft.com/visual-cpp-build-tools/). If so, follow the instructions from the previous link.
-
-Even if Visual Studio is already on your machine, rustup will not verify if the required components are present. If you experience issues with the `rustup` installation on Windows, please follow [these instructions](https://rust-lang.github.io/rustup/installation/windows-msvc.html) to manually add the missing components.
-:::
-
 To verify that the installation, open a terminal and run `rustup --version`. If everything went well, you should see an output similar to this:
 
 ```shell
@@ -32,7 +34,7 @@ The simplest installation method involves using the `cargo` packet manager, but
 sudo apt install -y pkg-config libudev-dev cmake git
 ```
 
-* On Mac OS and Windows, no additional setup is needed.
+* On Mac OS, no additional setup is needed.
 
 After that, use `cargo` to install `probe-rs`:
 
@@ -107,6 +109,11 @@ git clone https://github.com/OxidosAutomotive/tock.git --branch=psoc6-workshop
 cd tock
 ```
 
+:::note NixOS VM users
+You don't have to clone the Tock OS repository, it is already cloned in the home directory.
+You will have to run `nix-shell` once you enter the `tock` directory.
+:::
+
 The configuration for the various boards supported can be found in the `boards` directory. To compile the kernel, you can use the `cargo flash` utility.
 
 ```shell
@@ -118,6 +125,11 @@ Alternatively, you can use the `cargo flash` while inside the board's directory.
 
 If you did everything correctly, you should be able to use the `tockloader listen` command to interact with the kernel. When prompted to select a serial port, pick the one that ends with `KitProg3 CMSIS-DAP`.
 
+:::note NixOS VM users
+Currently, `tockloader` doesn't work on NixOS, but we have included the program `picocom`
+which you can use with the following command: `picocom -b 115200 /dev/ttyACM0`. (use `sudo` if it gives an error about permissions)
+:::
+
 ```shell
 tockloader listen
 [INFO   ] No device name specified. Using default name "tock".
@@ -131,7 +143,7 @@ Which option? [0] 1
 [INFO   ] Using "/dev/cu.usbmodem1103 - KitProg3 CMSIS-DAP".
 [INFO   ] Listening for serial output
 
-$tock
+tock$
 ```
 
 ### Compiling an application
@@ -143,6 +155,12 @@ git clone https://github.com/ipworkshop/libtock-c.git --branch=remove-risc
 cd libtock-c
 ```
 
+:::note NixOS VM users
+You don't have to clone the libtock-c repository, it is already cloned in the home directory.
+You will have to run `nix-shell` once you enter the `libtock-c` directory.
+Make sure you don't run that command if you already ran `nix-shell` inside another directory (either run `exit` before, or use another shell).
+:::
+
 Navigate to the `examples/blink` folder and take a look at the C application structure found in `main.c`. To compile the application, simply run `make`. This command will built the example applications for all target architectures supported by the library. Apps are compiled into TBFs (Tock Binary Format), and can be found in the `build/<arch>` sub-directories. Tock also generates an archive of the same app, compiled for multiple architectures, for ease of use and portability, called a TAB(Tock Application Bundle) which can be loaded using the `tockloader` utility.
 
 ### Flashing the application
@@ -168,7 +186,7 @@ Which option? [0] 1
 [INFO   ] Using "/dev/cu.usbmodem1103 - KitProg3 CMSIS-DAP".
 [INFO   ] Listening for serial output
 
-$tock list
+tock$ list
  PID    ShortID    Name                Quanta  Syscalls  Restarts  Grants  State
  0      Unique     blink                    0        84         0   1/ 8   Yielded
 ```