Beginner at OpenROAD , how to understand the tool perfectly?

[ReemAbuRajab7]

I worked previous on synopsis tool to perform each stage in physical design using special commands for each stage.

Recently I have built the OpenROAD and use ' make ' command to compile my code and it results the databases for each stage in physical design , now what next after adding new design? I read large pages in the documentation but I think the arrangement of it for a beginner it's not clear enough, I lost in how to use OpenROAD in the right way .

And another question , how to perform each stage alone and see it's result ?

Last question: what concepts or anything I need to learn before using OpenROAD?

[titan73]

I have a template script for basic operations. It can be useful to start:

# Read lef files (odb)
read_lef technology.lef
read_lef std_cells.lef
read_lef macro.lef

# Read lib files (sta)
read_liberty std_cells.lib
read_liberty macro.lib

# Read design (odb)
read_verilog netlist.v
link_design top_digital

# Report design
report_cell_usage
report_design_area

# Read timing constraints
read_sdc -echo constraints.pt

# Read power intent
read_upf -file power.upf

# Get reference to design
set blk [ord::get_db_block]

# Create floorplan
read_def -floorplan_initialize floorplan.def
set fp_area [ord::get_die_area]
initialize_floorplan -die_area $fp_area -core_area $fp_area -site xxx (-flip_sites xxx)

# Place all pins
place_pins ...

# Place specific pins
place_pin ...

# Create tracks
make_tracks

# Place macro
place_macro -macro_name i_macro -location {x y}
set master [[[$blk findInst i_macro] getMaster] getName]
cut_rows -endcap_master $master -halo_width_x ... -halo_width_y ...

# Insert tie cells
insert_tiecells "TIE0/Z" -prefix "TIE_ZERO_"
insert_tiecells "TIE1/Z" -prefix "TIE_ONE_"

# Power grid / Power network delivery (pdn)
add_global_connection -net VREG -pin_pattern {^VDD$} -power
add_global_connection -net DGND -pin_pattern {^GND$} -ground
set_voltage_domain -power VDD -ground GND
define_pdn_grid -name "Core" -starts_with POWER
add_pdn_stripe -followpins -layer M1 -width ...
add_pdn_stripe -layer M4 -width ... -pitch ... -spacing ... -offset ...
add_pdn_stripe -layer M5 -width ... -pitch ... -spacing ... -offset ...
add_pdn_connect -layers {M1 M4}
add_pdn_connect -layers {M4 M5}
pdngen

set_routing_layers -signal M2-M4 -clock M2-M4

# Global Placement (gpl)
global_placement

# Detail placement (dpl)
detailed_placement

# Clock tree synthesis (cts)
clock_tree_synthesis -buf_list {...}

# Detail placement (dpl)
detailed_placement

# *Global routing (grt)
global_route -verbose -allow_congestion

# Detail routing (drt)
detailed_route -output_drc violations.drc -output_cmap congestion_map.cmap

# Wrote database
write_db output.odb

# Make a snapshopt
set height [ord::dbu_to_microns [[[ord::get_db_block] getBBox] getDY]]
set resolution [expr $height / 1000 /4]
save_image -resolution $resolution design.png

[maliberty]

That's a decent learning flow though it lacks macro placement.

[maliberty]

If you want to understand the flow more deeply you'll eventually need to look at the scripts involved https://github.com/The-OpenROAD-Project/OpenROAD-flow-scripts/tree/master/flow/scripts