Re: [Iverilog-devel] Vhpi/vhpi and vhdl

[Martin W. <mai...@ma...>]

Jon Taylor wrote:
> Hi all,
>
> I am the author of Controlix, an operating system written in vhdl. I am
> currently developing it using GHDL as the compiler, and the system
> interface uses vhpi calls. Works OK on top of POSIX, but Icarus' vpp is
> written in c instead of in ada, making a static linkage job for bare metal
> targeting much more feasible.
>
> Afaics from perusing the sources, neither vhpi or vpp are currently
> supported by vhdlpp. If someone is already looking into writing support for
> this, I'd be happy to test, otherwise I might be able to take a crack at it
> myself (I have the coding time available).
>
Hello Jon,

Sorry nobody has replied to you sooner. As far as I know nobody is working on 
supporting VHPI - hopefully Steve or Orson will chime in if I'm wrong.

I'm not familiar with VHPI myself, but at a quick glance it seems very similar 
to VPI. This means support would need to be added to the simulator runtime 
(vvp). This may not be a big deal in itself, but I suspect the problem you 
will run into is that vhdlpp is just a preprocessor that converts VHDL to 
SystemVerilog, so some knowledge of the original code may get lost on the way. 
Furthermore, quite a lot of knowledge about SystemVerilog types are also lost 
during compilation, and vvp's support for VPI is far from complete... But 
having said that, I don't want to discourage you from having a crack at it!

By vpp, do you mean the VHDL preprocessor?

Martin