Re: Flame Linus to a crisp!

Timothy Miller
2003-04-24T20:07:18Z

Linus Torvalds wrote:

>On Thu, 24 Apr 2003, Timothy Miller wrote:
>
>
>>For their smaller devices, Xilinx has a free "WebPack" which is a
>>complete Verilog synthesizer (I don't know if it does VHDL), as well as
>>place & route, of course. I think it'll do up to Virtex II 250. It
>>also tends use fewer gates for a given design than the version of
>>Leonardo Spectrum we have. It just doesn't have a simulator, which is
>>vital to any good development process. Also, the Web Pack only runs
>>under Windows. Maybe it'll work with WINE?
>>
>>
>
>It does work with wine - but it's sad how horrible the command line tools
>are (they were apparently first done under UNIX, and then ported to
>Windows, and they got the Windows command line interface and trying to use
>them in a sane way with Wine is not exactly much fun).
>
>But yes, with Wine and a few scripts you can actually make the tools
>usable under Linux - I tried them out and had a small silly "pong" game
>running on one of those things (a 100k device on one of the cheap
>development boards).
>
>I have to admit that I would hate to actually use those tools for any real
>work, though.
>
>
>
Where I work we have used the Web Pack (5.1, I believe) for "real work",
although you can't trust its static timing. Beyond a certain
utilization, it completely lies to you, and we can't get it to work
right, no matter how much we over-constrain a design. All we can do is
synthesize and then thoroughly test in real hardware (which isn't hard
to do when all you're doing is a simple pixel-processing pipeline --
either it works, or you get obvious sprinkless all over the monitor
screen). If that doesn't work, we get really clever to reduce area, or
we go to a bigger device. What can you do with free but closed-source
software? :) Designing for FPGA's is a real pain. Although the ASIC I
did was a lot more complex, the process was a lot more straight-forward
and the tools didn't lie to you.