NEXTPNR-HIMBAECHEL-GOWIN(1)

💅 nextpnr-himbaechel-gowin 💅

okay so bestie, welcome to nextpnr-himbaechel-gowin — that's the Next Generation Place and Route tool, and she's a manual page from General Commands (section 1, iykyk). This is Version 0.10-5 and she is literally the main character of your FPGA flow. Let's get into it 🫶

✨ NAME ✨

nextpnr-himbaechel-gowin — Next Generation Place and Route. That's it, that's the whole vibe. Periodt. 💅

🦋 DESCRIPTION 🦋

nextpnr-himbaechel-gowin — Next Generation Place and Route (Version 0.10-5).

Like... she places. She routes. She does the whole thing. Slay.

🌸 General options: 🌸

These are the big main-character flags, bestie. Every single one matters, no skipping ngl:

• -h, --help — show help. your safe space 🥺
• -v, --verbose — verbose output. she talks. a lot. and we love that for her.
• -q, --quiet — quiet mode, only errors and warnings displayed. the introvert setting 🎀
• --Werror — Turn warnings into errors. spicy!! a warning is now a full-on error, no cap.
• -l, --log arg — log file, all log messages are written to this file regardless of -q. so even in quiet mode, the log file gets everything. icon behavior.
• --debug — debug output. all of it. every crumb. 🙈
• --debug-placer — debug output from placer only. just the placer's little diary 📓
• --debug-router — debug output from router only. router gets her own diary too 💜
• --threads arg — number of threads for passes where this is configurable. yes she multithreads, we stan.
• -f, --force — keep running after errors. unbothered. unphased. literally keeps going 😭💀
• --run arg — python file to execute instead of default flow. you're the director now.
• --pre-pack arg — python file to run before packing. warmup era ✨
• --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. aftercare 🫶
• --on-failure arg — python file to run in event of crash for design introspection. when it all falls apart, she still wants to know why 😭
• --json arg — JSON design file to ingest. feed her 🍓
• --write arg — JSON design file to write. she gives back 💖
• --top arg — name of top module. who's the main character module? 🎀
• --seed arg — seed value for random number generator. the chaos dial.
• -r, --randomize-seed — randomize seed value for random number generator. chaos dial but ✨spontaneous✨
• --placer arg — placer algorithm to use; available: sa, heap, static; default: heap. she ships with heap by default, deluxe behavior 👑
• --router arg — router algorithm to use; available: default, router1, router2; default: default. also default is literally default. yes.
• --slack_redist_iter arg — number of iterations between slack redistribution.
• --cstrweight arg — placer weighting for relative constraint satisfaction. how much she cares about your constraints, basically.
• --starttemp arg — placer SA start temperature. yes, simulated annealing. it's giving physics lab 🌡️
• --pack-only — pack design only without placement or routing. just the packing, nothing else. minimal queen.
• --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. 🙈 loops? never met her.
• --ignore-rel-clk — ignore clock-to-clock relations in timing checks. clock drama? blocked. 💀
• -V, --version — show version. hi what's your version bestie
• --test — check architecture database integrity. a little health check-up 🩺
• --freq arg — set target frequency for design in MHz. MHz!! remember the units!! 🔥
• --timing-allow-fail — allow timing to fail in design. permission to fumble, granted 🫶
• --no-tmdriv — disable timing-driven placement. timing-driven? not today.
• --sdc arg — Generic timing constraints SDC file to load.
• --sdf arg — SDF delay back-annotation file to write.
• --sdf-cvc — enable tweaks for SDF file compatibility with the CVC simulator. shoutout CVC simulator, she's niche but iconic.
• --no-print-critical-path-source — disable printing of the line numbers associated with each net in the critical path. bye bye line numbers 🎀
• --placer-heap-alpha arg — placer heap alpha value (float, default: 0.1). a float!! write it as a float!!
• --placer-heap-beta arg — placer heap maximum placement density (float, default: 0.9). density dial, almost maxed out by default.
• --placer-heap-critexp arg — placer heap criticality exponent (int, default: 2). an int this time, mind you.
• --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). so 0 means no timeout — she'll wait forever for that cell 😭
• --static-dump-density — write density csv files during placer-static flow. csv files!! data!! 📊
• --parallel-refine — use new experimental parallelised engine for placement refinement. experimental!! new!! parallelised!! 🔥
• --router2-heatmap arg — prefix for router2 resource congestion heatmaps. heatmap hot girl summer 🌈
• --tmg-ripup — enable experimental timing-driven ripup in router.
• --router2-tmg-ripup — enable experimental timing-driven ripup in router (deprecated; use --tmg-ripup instead). bestie she's deprecated, use --tmg-ripup, I'm begging 🥺
• --router2-alt-weights — use alternate router2 weights.
• --report arg — write timing and utilization report in JSON format to file. receipts!! 🧾
• --detailed-timing-report — Append detailed net timing data to the JSON report. capital A Append, she's thorough.
• --placed-svg arg — write render of placement to SVG file. aesthetics ✨🎨
• --routed-svg arg — write render of routing to SVG file. more aesthetics ✨🎨

ngl bestie, --force means she keeps running after errors. errors. plural. she's brave and maybe a little unhinged 😭 but hey, that's the flag's whole documented deal, so it is what it is.

🧚 Architecture specific options: 🧚

The himbæchel-flavored ones, aka the part where you tell her which chip you're on:

• --device arg — name of device to use. which chip are we serving today 💅
• --chipdb arg — override path to chip database file. you can point her somewhere else fr fr
• --list-uarch — list included uarches. the whole menu 🍓
• -o, --vopt arg — options to pass to the himb??chel uarch (use help as argument to get more info). yep, literally pass help as the argument and she'll spill the details 🫶

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okay that's the whole page bestie, every single flag accounted for, no cap 💖 slay responsibly and remember: <italic>arg</italic> means she needs a value, and things in backticks are literal — type them exactly, character for character, or it's not gonna work 😭🦋

sign-off time 🎀 this here page is for nextpnr-himbaechel-gowin, version 0.10-5, dated March 2026 — that's the source/version and date, folded into a cute lil goodnight. love u, go place and route something iconic ✨💜👑