Upsilon docker development environment setup.

# Dockerfile style guide

Dockerfiles should be simple. The Dockerfiles should be readable to a
beginner.

# Setup steps

Change directory to `build`.

## Installing OpenFPGALoader

Install [openFPGALoader][1]. If this program is not in your repositories,
run `make openFPGALoader` to fetch and install the program.

[1]: https://trabucayre.github.io/openFPGALoader/index.html

## Setup Rootless Docker

Docker allows you to run programs in containers, which are isolated
environments. Build environments can be set up automatically, and re-setup
whenever needed.

If you have issues with docker, try adding to `~/.config/docker/daemon.json`

    {
       "storage-driver": "fuse-overlayfs"
    }


## Download and Install Python3

Install `python3` and `python3-pip`.

## Clone External Repositories

Run `make clone`. You may need to download the upsilon repositories
and put them in the same folder as the Makefile.

## Setup Network

Plug in your router/switch to an ethernet port on your computer. If your
computer is usually wired to the network, you will need another ethernet
port (a PCI card is ideal, but a USB-Ethernet port works).

Set the ethernet port to static ip `192.168.1.100/24`, netmask `255.255.255.0`,
gateway `192.168.1.1`. Make sure this is not the default route. Make sure
to adjust your firewall to allow traffic on the 192.168.1.0/24 range.

If your local network already uses the 192.168.1.0/24 range, then you must
modify `upsilon/firmware/soc.py` to use different IPs. You must rebuild the
SoC after doing this.

## Setup Images

Run `make images` to create all docker images.

## Setup and Run Containers

For `NAME` in `hardware`, `opensbi`, `buildroot`:

1. Run `make $NAME-container` to build the container. You usually only need
   to do this once.
2. If the container already exists, do `docker container start upsilon-$NAME`.
3. Run `make $NAME-copy` to copy Upsilon's code into the container.
4. Run `make $NAME-execute` to build the data.
5. Run `make $NAME-get` to retrieve the build artefacts.

If you do not delete the container you can run

	make $NAME-copy $NAME-execute $NAME-get

when you need to rebuild. If you need shell access, run `make $NAME-shell`.

## Launch TFTP Server

Install py3tftp (`pip3 install --user py3tftp`). Then run `make tftp` to
launch the TFTP server. Keep this terminal open.

## Flash FPGA

Plug in your FPGA into the USB slot. If you have installed openFPGALoader
by your package manager, run `make OPENFPGALOADER=openfpgaloader flash`.
If you installed it using `make openFPGALoader`, then just run `make flash`.

In a second you should see messages in the TFTP terminal. This means your
controller is sucessfully connected to your computer.

## SSH Access

Add the following to your SSH config:

	Host upsilon
		HostName 192.168.1.50
		StrictHostKeyChecking no
		UserKnownHostsFile /dev/null
		IdentityFile upsilon_key
		User root
		LogLevel QUIET

Then copy the file `build/upsilon_key` to `$HOME/.ssh`.

When the FPGA is connected you can access it with `ssh upsilon` (password
`upsilon`).

Wait about a minute for Linux to boot.

## Launch FPGA Shell (Optional)

If you cannot access the FPGA through SSH, you can launch a shell through
UART.

You will need to install [LiteX](https://github.com/enjoy-digital/litex).
Download and run `litex_setup.py`.

Run `litex_term /dev/ttyUSB1`. You should get messages in the window with
the TFTP server that the FPGA has connected to the server. Eventually you
will get a login prompt (username `root` password `upsilon`).

## Copy Library

Run `make copy` to copy the Micropython Upsilon library to the FPGA. After
this the modules `comm` and `mmio` are available when running scripts in
`/root`.