Hello, > On 23 Dec 2013, at 4:40 am, Neeraj Yadav <[email protected]> > wrote: > > > I have made a small cloud based verilog/vhdl simulator which uses > > GHDL > > and Icarus for VHDL and Verilog respectively. > > > > http://www.tarangeda.com > > > > I want comments of ghdl developers, anything you want to say. > > Makes a great argument for binary distribution under the Affero > GPLv3. As Tristan noted earlier a binary work comprised of gcc and > a ghdl front end the gcc compiler is distributed under the terms of > the GPLv3, which allows adhesion to the Affero GPLv3.
[...] > The ghdl mcode version is distributed solely under the the GPLv2. Let's clarify this point: the license is GPLv2 *or any later version*. That's why I mentioned GPLv2+ [...] > As far as I can tell, ghdl isn't fully compliant with the VHDL > Standard (IEEE Std 1076-1993, -2002 or -2008). Off hand as far as > marketable 'product' distinctiveness ghdl has none. While Tristan > doesn't share his plans for ghdl (his original release plan is badly > dated), my interest is primarily in achieving full -1993 standard > compliance. The Brians are driven by insuring platform > availability. I think that ghdl is compliant with VHDL 1993 and 2002. That's modulo bugs, but I think that all features are implemented. If not, do not hesitate to raise issues. [...] > > 2. Is it okay the way I am using ghdl on my site?Are there any > > license > > restriction etc? > > I'm not aware of any licensing terms for ghdl that are in conflict > with your usage (a personal opinion only). That sounds like > something for which you might seek legal counsel. > > As the GPL says, you aren't 'conveying a covered work', unless you > are providing download access to elaborated (executable) VHDL > models. (The ghdl runtime library is released under the GPLv2, > apparently requiring distribution under the terms of the GPL). > Again, you might want to seek legal counsel. > > > I also want to contribute to GHDL, I need someone to give me a > > clear > > idea how far ghdl from say a OEM version of ModelSim? > > There are obvious limitations on ghdl. > > It doesn't have the an interactive shell for simulation > (run/stop/step, save restore). > > It doesn't have the ability (currently) to select signals saved to a > waveform. This likely has a performance impact (and is something > Tristan has indicated support for in the past). > > It isn't a dual HDL front end system. You're web site can't do mixed > HDL models using ghdl. > > It's not a GUI based tool (and frankly enclosing it with a web > interface doesn't make it one). > > It's utility for co-simulation is limited. (ghdl also doesn't support > specification of a resolution limit for type TIME (See 3.1.3.1 > Predefined physical types). > > Any sense of urgency on the part of someone making money off ghdl in > conveyng bug reports and feature requests doesn't have the same > impact it might have for a proprietary product generating income > (for those active developers). Without supplying your own end user > support you're use of ghdl doesn't widen the audience of ghdl users > appreciably. > > ghdl's warning and error messages aren't always accurate and in some > cases segmentation faults occur instead. Modelsim's verror facility > for instance (or comparable for Altera) goes a long way to user > friendliness. > > There's a general shortcoming in the documentation and usage > examples. > > The amount of release or validation testing ghdl undergoes is > (currently) limited. > > ghdl's performance doesn't match commercial offerings on the same > platform. Some proprietary performance enhancements may be (still) > covered by patents. > > (And a lot of this points to intended users, a commercial product is > intended for and must be responsive to a wider audience.) > > In general those denigrating ghdl for it's shortcomings are those who > would be interested in it's commercial exploitation otherwise. The > rest of us like to focus on what ghdl does right. > > ghdl appears to standard compliantly deal with configuration, likely > said of few other tools. That being said, it's an underutilized > facility in the face of EDA being dominated by FPGA development. > > It doesn't compete with proprietary offerings. And if it were > comparable in features, support and user friendliness it'd ruin the > market for proprietary VHDL simulators offering full features > instead of a limited freemium model. Most of that is correct. GHDL was started as an hobby project. Regards, Tristan. _______________________________________________ Ghdl-discuss mailing list [email protected] https://mail.gna.org/listinfo/ghdl-discuss
