[Eda-dev] qflow Docker experiment

Tim Edwards tim at efabless.com
Fri Jul 5 09:04:32 EDT 2019

Hello Øyvind,

 > # /usr/local/share/qflow/bin/addspacers -stripe 5 150 PG -p vdd -g gnd -f
 > FILL -O -l /usr/local/share/qflow/tech/osu035/osu035_stdcells.lef -o
 > ControlUnitTestBench_filled.def ControlUnitTestBench
 > corrupted size vs. prev_size
 > Aborted (core dumped)
 > *Questions that come to mind:*
 >  - Looks like "addspacers" is part of qflow, but is the "Aborted (core
 >  dumped)"  a somewhat disturbing error message for already invalid
 >  input(incorrect data generated upstream) or is it a problem in
 >  "addspacers"? Which module should I try to upgrade/downgrade?

In qflow-1.4, "addspacers" is a recent conversion of what used to be a
Tcl script into a C executable, as my Tcl DEF parser was too lightweight
and I needed something more thorough.  However, as a recent addition to
the code base, it is the most likely to fail for obscure reasons.

Since you are using the OSU035 techfiles from qflow, all I need is the
file "ControlUnitTestBench.def" from your layout/ directory (the
pre-routed one, but if qflow did not get beyond the placement stage, then
that would be the only one existing).  Can you please send me a copy of
the file so that I can try to duplicate the error?  It looks to me like
it is probably a coding error.

 >   - Can I get something newer than osu035 (350nm, right?). I've heard
 >   about open source/academic 40nm technology files, but is that generally
 >   available these days?

Qflow ships with four different "academic" technologies:  OSU050, OSU035,
OSU018, and FreePDK45.  I suppose that FreePDK45 is what you are looking
for.  Note that you can only get "academic" (non-proprietary, and also
not associated with any real fab process) technologies with the qflow
distribution.  We at efabless.com have been working hard to convince the
foundries that it is in their best interest to open source their process
specifications.  Whether or not it is due to our efforts (probably ours
and a lot of others, as well), there is some movement in that direction
from some of the friendlier foundries (X-Fab, Global, SkyWater).


| R. Timothy Edwards (Tim)       | email: tim at efabless.com             |
| efabless, inc.                 | web:   http://www.efabless.com      |
| 2570 N. 1st St., Suite 200     | phone: (240) 489-3255               |
| San Jose, CA 95131             | cell:  (408) 828-8212               |

More information about the Eda-dev mailing list