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#openlane
Title
# openlane
h

Hanssel Enrique Morales Norato

11/29/2020, 8:47 PM
I'm trying to run a design which instantiates multiple DFFRAM and I'm getting the following:
Im using  
set ::env(FP_HORIZONTAL_HALO) 10
and
set ::env(FP_VERTICAL_HALO) 10
to adjust HALO but it keeps failing
t

tnt

11/29/2020, 8:56 PM
Check the intermediate DEF to see what's going on.
It's possible the core shape that got picked jus can't fit all the DFF RAM ...
h

Hanssel Enrique Morales Norato

11/29/2020, 9:13 PM
That seems to be the problem but actually Im not setting the core shape so should I set the
DIE_AREA
or there its a way to keep it automatic ? btw where its located the documentation for the tcl env variables of openlane ?
t

tnt

11/29/2020, 9:19 PM
The automatic size is not very advanced, it doesn't look at the shape of macro or anything, it just tried to pick a square of roughly the right area, irrespective of macro shape or anything.
h

Hanssel Enrique Morales Norato

11/29/2020, 9:38 PM
Thanks for your support, I oversize the design in order to check if it works and now I'm getting a different error and the error.log doesn't show more information than
child process exited abnormally
t

tnt

11/29/2020, 9:39 PM
probably segfault or ran out of memory
h

Hanssel Enrique Morales Norato

11/30/2020, 3:13 PM
I have 16 GB ddr4 ram so Idk what to do to get rid of it.
t

tnt

11/30/2020, 3:17 PM
Instanciating large macros is a pain and oesn't work well ATM. I had to resort to manually specify area, manually placing the macro and using several custom OpenDB scripts to make it work for me. Took me the better part of a week to get a design that places and routes.