PCIe: need help with transactions and BFM

Are there any functions or wrappers that could help me to generate a TLP from my data on the application layer side? Say, I have CAFEFADE and want to send it via Avalon-ST TX. I need to send all the needed signals like sop, valid etc. and transform my CAFEFADE into a TLP. How do I do that and is there anything I'm omitting?

Also, can I simply send some arbitrary data from the application layer (the latter being master)? I don't need to write it into the RC shared memory or anything like that, I just want the packet be received by the BFM (testbench) on the other side of the PCIe and be shown in the simulator without a need to save it (well, actually the packet is going to be parsed by the custom host driver, so I don't think I need all this stuff about shared memory).

Any kind of help will be useful. Thank you in advance!