https://open-source-silicon.dev
Join Slack
hello, anyone know if there there is some sort of routing keepout or halo placed around macros by de...
# openlane
a
hello, anyone know if there there is some sort of routing keepout or halo placed around macros by default?
v
Check variables 
PL_MACRO_HALO
and 
PL_MACRO_CHANNEL
a
thank you, will do
hmmm what about 
set ::env(MACRO_BLOCKAGES_LAYER) {Metal1 Metal2 Metal3 Metal4 Metal5}
also can't find documentation 
GRT_MACRO_EXTENSION
does
v
Normally if SRAM macros placed, to avoid DRC errors 
GRT_OBS
used. But i'm not quite understand your requirement. Tagging @Matt Liberty for further help
a
i'm just trying to understand why the pins on my custom layout aren't accessible. it looks like there's enough space between them but it's possible that the density just means the router gives up.
separately, i'd like to understand this giant empy-space area between the tiny macro and the rest of the cells:
image.png
v
a
possibly, i'm not sure i understand what that bug is about
ah yes, i imagine this is related. placing pins shouldn't preclude routes that might otherwise be reachable
i guess i thought this was part of the global router's ripup/reroute iteration
m
pin access problems are local to the macro itself and not about density (unless you have a cell abutting the macro which would be weird)
a
thanks @Matt Liberty - do you know more about how access is negotiated at the cells? how hard does the router try to find a path to a pin? or maybe how to modify the cell to make it easier for the router?
m
It is hard to say without seeing the problem. You could either open a GH issue with test case or try out: detailed_route_debug -pa -pa_markers -pin <inst>:<pin> and run OR detailed routing in the GUI. It will stop and show you the drc errors found while trying to access that pin
a
the pins themselves are drc clean and further apart than metal 3 pitch, for example. which repo is most appropriate for this issue to be filed in?
(you can see pic above, i'll repro)
m
I don't know where the pin in question is in that image. Also that is gds not lef so it is less helpful
a
good to know, i'll mark them
hmmm i made the access pins comically large and spaced out, i suspect something else is afoot
22 Views
Open in Slack
PreviousNext
Powered by

What is Linen?

Linen is a search-engine friendly community platform. We offer integrations with existing Slack/Discord communities and make those conversations Google-searchable.

Powered by