OpenDP¶
OpenDP: Open-Source Detailed Placement Engine
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Visualized detailed placement result using |
Features:
Fence region and multi-height cells. (ICCAD 2017 Contest benchmarks)
Fragmented ROWs.
Macro blocks.
Commands¶
The detailed_placement command performs detailed placement of instances
to legal locations after global placement.
set_placement_padding -global|-instances insts|-masters masters
[-left pad_left] [-right pad_right]
detailed_placement [-max_displacement disp|{disp_x disp_y}]
check_placement [-verbose]
filler_placement [-prefix prefix] filler_masters
optimize_mirroring
The set_placement_padding command sets left and right padding in multiples
of the row site width. Use the set_placement_padding command before
legalizing placement to leave room for routing. Use the -global flag
for padding that applies to all instances. Use -instances
for instance-specific padding. The instances insts can be a list of instance
names, or an instance object returned by the SDC get_cells command. To
specify padding for all instances of a common master, use the -filter
“ref_name == get_cells.
The set_power_net command is used to set the power and ground special
net names. The defaults are VDD and VSS.
The -max_displacement argument to detailed_placement specifies how
far an instance can be moved when finding a site where it can be placed. The default values are
{500 100} sites. The x/y displacement arguments are in microns.
The check_placement command checks the placement legality. It returns
0 if the placement is legal.
The filler_placement command fills gaps between detail-placed instances
to connect the power and ground rails in the rows. filler_masters is a
list of master/macro names to use for filling the gaps. Wildcard matching
is supported, so FILL* will match, e.g., FILLCELL_X1 FILLCELL_X16 FILLCELL_X2 FILLCELL_X32 FILLCELL_X4 FILLCELL_X8. To specify a different naming prefix
from FILLER_ use -prefix <new prefix>.
The optimize_mirroring command mirrors instances about the Y axis in
a weak attempt to reduce total wirelength (HPWL).
Example scripts¶
Regression tests¶
Limitations¶
FAQs¶
Check out GitHub discussion about this tool.
License¶
BSD 3-Clause License. See LICENSE file.