Advantage of TLM fifo over a mailbox

OVM
1

Hi All,

Can somebody tell me any advantage of using TLM fifo over a mailbox for connecting components?
Suleesh

2

Suleesh,

A TLM fifo is a mailbox implemented using standard TLM ports and exports as an API to the mailbox. The TLM API gives you a separation of concerns which in turn promotes re-usability and maintainability.

Let’s say you have two components: A and B. Component A has a thread doing puts and component B has a thread doing gets. They are both connected through a common mailbox which means they both must declare handles to a matching mailbox type. This creates an unwanted dependency. At some point, I might want some other component other than a mailbox to connect to, like some kind of arbitrator. So I would have to modify the handles types in the components.

TLM gets rid of that dependency. Component A can have a put_port and just requires that what it is connected to implements a put method. Component B can have a get_port and just requires that what it is connected to implements a get method.

Dave

3

In reply to dave_59: what type of dependency it ll create

4

In reply to sivareddy:
As I said above, using a mailbox forces a connection between components to use a mailbox protocol where there is one thread calling a mailbox.put(t), and another thread calling a mailbox.get(t).

When you use a TLM port, you just call put(t) and have no knowledge of how the put is implemented. You just know that a put() blocks until the transfer of t completes. In the case of a TLM fifo, the TLM put()happens to be implemented as a mailbox.put(), but the calling process does not know that. It is possible that the implementation of put does everything and there is no need for another process to do a get().