Hardware abstraction layer for Calendars

[lmbollen]

Our Bittide system contains three types of components that contain a calendar:

• Gather units
• Scatter units
• Switch

Gather units are the sources of bittide links, their calendar contains a (currently repeating) schedule that dictates which frames are send over the link, so for each clock cycle the calendar will present a Index memDepth.

Scatter units are the sinks of bittide links, their calendar contains a similar schedule that dictates where the received frames are written in the scatter memory. So for each clock cycle, the calendar will also present a Index memDepth.

Switches are the link interconnects. A switch receives multiple links and produces multiple links. For each link, the switch's calendar will present a Vec n (Index outLinks) that determines for each outgoing link, from which incoming link it sources the outgoing frame.

Since entries of the calendars are expected to be repeated many times, it utilizes run length encoding to encode a number of repetitions
We need:

• A way to represent calendars in rust
• A hardware abstraction layer to interface with the calendar component

The hardware abstraction layer needs to be able to:

• Write calendars
• Swap the active and inactive calendar