---
name: "nextpnr-generic"
section: "1"
platform: "linux"
package: "nextpnr-generic"
version: "0.7-1+b2"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/nextpnr-generic"
---

# nextpnr-generic(1)

Next Generation Place and Route

## NAME

nextpnr-generic - Next Generation Place and Route

## DESCRIPTION

"nextpnr-generic" **--** Next Generation Place and Route (Version 0.7-1+b2)

### General options:

- **-h** \[ **--help** \]

  show help

- **-v** \[ **--verbose** \]

  verbose output

- **-q** \[ **--quiet** \]

  quiet mode, only errors and warnings displayed

- **--Werror**

  Turn warnings into errors

- **-l** \[ **--log** \] arg

  log file, all log messages are written to this file regardless of **-q**

- **--debug**

  debug output

- **--debug-placer**

  debug output from placer only

- **--debug-router**

  debug output from router only

- **--threads** arg

  number of threads for passes where this is configurable

- **-f** \[ **--force** \]

  keep running after errors

- **--run** arg

  python file to execute instead of default flow

- **--pre-pack** arg

  python file to run before packing

- **--pre-place** arg

  python file to run before placement

- **--pre-route** arg

  python file to run before routing

- **--post-route** arg

  python file to run after routing

- **--on-failure** arg

  python file to run in event of crash for design introspection

- **--json** arg

  JSON design file to ingest

- **--write** arg

  JSON design file to write

- **--top** arg

  name of top module

- **--seed** arg

  seed value for random number generator

- **-r** \[ **--randomize-seed** \]

  randomize seed value for random number generator

- **--placer** arg

  placer algorithm to use; available: sa, heap; default: heap

- **--router** arg

  router algorithm to use; available: router1, router2; default: router1

- **--slack\_redist\_iter** arg

  number of iterations between slack redistribution

- **--cstrweight** arg

  placer weighting for relative constraint satisfaction

- **--starttemp** arg

  placer SA start temperature

- **--pack-only**

  pack design only without placement or routing

- **--no-route**

  process design without routing

- **--no-place**

  process design without placement

- **--no-pack**

  process design without packing

- **--ignore-loops**

  ignore combinational loops in timing analysis

- **--ignore-rel-clk**

  ignore clock-to-clock relations in timing checks

- **-V** \[ **--version** \]

  show version

- **--test**

  check architecture database integrity

- **--freq** arg

  set target frequency for design in MHz

- **--timing-allow-fail**

  allow timing to fail in design

- **--no-tmdriv**

  disable timing-driven placement

- **--sdf** arg

  SDF delay back-annotation file to write

- **--sdf-cvc**

  enable tweaks for SDF file compatibility with the CVC simulator

- **--no-print-critical-path-source**

  disable printing of the line numbers associated with each net in the critical path

- **--placer-heap-alpha** arg

  placer heap alpha value (float, default: 0.1)

- **--placer-heap-beta** arg

  placer heap beta value (float, default: 0.9)

- **--placer-heap-critexp** arg

  placer heap criticality exponent (int, default: 2)

- **--placer-heap-timingweight** arg

  placer heap timing weight (int, default: 10)

- **--placer-heap-cell-placement-timeout** arg

  allow placer to attempt up to max(10000, total cells^2 / N) iterations to place a cell (int N, default: 8, 0 for no timeout)

- **--parallel-refine**

  use new experimental parallelised engine for placement refinement

- **--router2-heatmap** arg

  prefix for router2 resource congestion heatmaps

- **--tmg-ripup**

  enable experimental timing-driven ripup in router

- **--router2-tmg-ripup**

  enable experimental timing-driven ripup in router (deprecated; use **--tmg-ripup** instead)

- **--router2-alt-weights**

  use alternate router2 weights

- **--report** arg

  write timing and utilization report in JSON format to file

- **--detailed-timing-report**

  Append detailed net timing data to the JSON report

- **--placed-svg** arg

  write render of placement to SVG file

- **--routed-svg** arg

  write render of routing to SVG file

### Architecture specific options:

- **--uarch** arg

  viaduct micro-arch to use (available: example, okami, fabulous)

- **--no-iobs**

  disable automatic IO buffer insertion

- **-o** \[ **--vopt** \] arg

  options to pass to the viaduct uarch