Re: [myhdl-list] Introduction and Question

[Daryl W. <dw...@ou...>]

Christopher Felton <chris.felton <at> gmail.com> writes:

> 
snip
> 
> It might be worth investigating if GHDL has updated the VPI/VHPI 
> interface in the latest version of GHDL.  I monitor the GHDL 
> mailing-list briefly and have not seen any updates.  I think the GHDL 
> developers have mainly focused on a move to mcode.  If the status of the 
> VPI/VHPI has not changed it will be some work to implement cosimulation 
> with GHDL.  It will require the missing VPI functions implemented in GHDL.
> 
snip
>
> I created this page and it was intended to be a working page towards 
> GHDL co-simulation support.  The page lists which VPI functions are 
> supported in GHDL (as of 03-Feb-2010).  The VPI function list was not 
> complete enough to attempt a VPI port for GHDL.  I do not know if things 
> have changed.
> 

Okay, I investigated this. I searched the current development repository for 
the VPI functions that you had listed as Unknown in the table. It seems that 
the following have at least some implementation (at least with the bleeding
edge repository version of GHDL). 

vpi_get_time() 
vpi_put_value() [ has a comment FIXME, so maybe not working too well ]

These were found in the file at the following URL: 
http://svn.gna.org/svn/ghdl/trunk/translate/grt/grt-vpi.adb 

However, vpi_free_object() and vpi_register_systf() are declared as dummy 
functions (I'm assuming this means that they are not implemented), and I 
could not find vpi_control() anywhere. I'm not an expert ADA programmer 
so I can't be certain that they are functioning 100% according to specs, but 
they have something there. I probably don't want to worry about 
implementing the missing functionality in ADA myself, so I'll have to take 
the route you suggested below. 

> 
> GHDL is not available for cosimulation.  But it is supported simulator. 
> The flow for using GHDL is to convert the testbenches and run a full 
> VHDL simulation that can be coordinated from Python.  See the following 
> for some more information.
> 
> http://www.myhdl.org/doc/current/whatsnew/0.6.html#conversion-of-test-benches
> 
> Regards,
> Chris
> 

Thanks for pointing this out to me. Sorry I missed it. I'll look through 
it and see what I can do. If need be, I can always just write VHDL test 
benches for later simulations, just thinking it might be nice to use python... 

Thanks,
Daryl