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High-Fanout Routing Pressure Report

packages/chip/docs/pd/high-fanout-routing-pressure-2026-05-18.md

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High-Fanout Routing Pressure Report

  • Run: pd/openlane/runs/RUN_2026-05-18_05-41-42
  • Routed netlist: pd/openlane/runs/RUN_2026-05-18_05-41-42/final/nl/e1_chip_top.nl.v
  • Synthesis JSON: pd/openlane/runs/RUN_2026-05-18_05-41-42/06-yosys-synthesis/e1_chip_top.nl.v.json
  • Reporting threshold: 100 load pins

Routed Large-Net Warnings

NetRouter pinsParsed pinsLoadsDriversDominant portsClassificationLikely RTL / action
net4891061061051RESET_B:53, DIODE:50, A:2, X:1reset_distributionLarge routed reset branch. Likely driven by rst_n_sync through OpenROAD-inserted max-cap buffers.

Synthesis-Level Fanout Hotspots

NetLoad pinsDriversSourceClassificationSample sinks
rst_n_sync42321/work/rtl/top/e1_chip_top.sv:28.11-28.21reset_distribution`$abc$197552$auto$blifparse.cc:396:parse_blif$222428.S
$abc$197552$auto$blifparse.cc:396:parse_blif$222431.S
$abc$197552$auto$blifparse.cc:396:parse_blif$222434.S
$abc$197552$auto$blifparse.cc:396:parse_blif$222437.S
$abc$197552$auto$blifparse.cc:396:parse_blif$222440.S
$abc$197552$auto$blifparse.cc:396:parse_blif$222443.S`
CLK_IN42230/work/rtl/top/e1_chip_top.sv:4.24-4.30clock_distribution`$auto$ff.cc:266:slice$26675.CLK
$auto$ff.cc:266:slice$26676.CLK
$auto$ff.cc:266:slice$26720.CLK
$auto$ff.cc:266:slice$26721.CLK
$auto$ff.cc:266:slice$26722.CLK
$auto$ff.cc:266:slice$26723.CLK`
$abc$197552$new_n112711621generated/no source attributesynthesis_generated_logic`$abc$197552$auto$blifparse.cc:396:parse_blif$200370.C
$abc$197552$auto$blifparse.cc:396:parse_blif$205421.A2
$abc$197552$auto$blifparse.cc:396:parse_blif$205481.A2
$abc$197552$auto$blifparse.cc:396:parse_blif$205512.B1
$abc$197552$auto$blifparse.cc:396:parse_blif$205520.B
$abc$197552$auto$blifparse.cc:396:parse_blif$205537.A2`
$abc$197552$new_n110071421generated/no source attributesynthesis_generated_logic`$abc$197552$auto$blifparse.cc:396:parse_blif$200101.B
$abc$197552$auto$blifparse.cc:396:parse_blif$200149.A2
$abc$197552$auto$blifparse.cc:396:parse_blif$200355.A
$abc$197552$auto$blifparse.cc:396:parse_blif$203595.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$203596.A
$abc$197552$auto$blifparse.cc:396:parse_blif$203604.B2`
$abc$197552$new_n163301371generated/no source attributesynthesis_generated_logic`$abc$197552$auto$blifparse.cc:396:parse_blif$205424.B1
$abc$197552$auto$blifparse.cc:396:parse_blif$205482.A2
$abc$197552$auto$blifparse.cc:396:parse_blif$205510.B1
$abc$197552$auto$blifparse.cc:396:parse_blif$205544.A2
$abc$197552$auto$blifparse.cc:396:parse_blif$206884.B1
$abc$197552$auto$blifparse.cc:396:parse_blif$206893.B1`
$abc$197552$new_n112741351generated/no source attributesynthesis_generated_logic`$abc$197552$auto$blifparse.cc:396:parse_blif$200370.D
$abc$197552$auto$blifparse.cc:396:parse_blif$205421.B1
$abc$197552$auto$blifparse.cc:396:parse_blif$205488.B1
$abc$197552$auto$blifparse.cc:396:parse_blif$205510.A2
$abc$197552$auto$blifparse.cc:396:parse_blif$205516.B
$abc$197552$auto$blifparse.cc:396:parse_blif$205519.B`
$abc$197552$new_n107081311generated/no source attributesynthesis_generated_logic`$abc$197552$auto$blifparse.cc:396:parse_blif$200371.A
$abc$197552$auto$blifparse.cc:396:parse_blif$205426.A2
$abc$197552$auto$blifparse.cc:396:parse_blif$205469.A2
$abc$197552$auto$blifparse.cc:396:parse_blif$205509.B1
$abc$197552$auto$blifparse.cc:396:parse_blif$205532.A2
$abc$197552$auto$blifparse.cc:396:parse_blif$206883.B1`
$abc$197552$new_n105561291generated/no source attributesynthesis_generated_logic`$abc$197552$auto$blifparse.cc:396:parse_blif$205491.A2
$abc$197552$auto$blifparse.cc:396:parse_blif$205509.A2
$abc$197552$auto$blifparse.cc:396:parse_blif$205526.A2
$abc$197552$auto$blifparse.cc:396:parse_blif$206883.A2
$abc$197552$auto$blifparse.cc:396:parse_blif$206895.A2
$abc$197552$auto$blifparse.cc:396:parse_blif$206902.A2`
$abc$197552$new_n149981141generated/no source attributesynthesis_generated_logic`$abc$197552$auto$blifparse.cc:396:parse_blif$204104.C1
$abc$197552$auto$blifparse.cc:396:parse_blif$204165.A
$abc$197552$auto$blifparse.cc:396:parse_blif$204190.A
$abc$197552$auto$blifparse.cc:396:parse_blif$204194.A
$abc$197552$auto$blifparse.cc:396:parse_blif$204200.A
$abc$197552$auto$blifparse.cc:396:parse_blif$204203.A`
$abc$197552$new_n150161071generated/no source attributesynthesis_generated_logic`$abc$197552$auto$blifparse.cc:396:parse_blif$204129.B
$abc$197552$auto$blifparse.cc:396:parse_blif$204131.B
$abc$197552$auto$blifparse.cc:396:parse_blif$204176.B1
$abc$197552$auto$blifparse.cc:396:parse_blif$204178.S
$abc$197552$auto$blifparse.cc:396:parse_blif$204181.A
$abc$197552$auto$blifparse.cc:396:parse_blif$204185.A`
mmio_wdata[2]1051/work/rtl/top/e1_chip_top.sv:32.18-32.28mmio_write_data_fanout`$abc$197552$auto$blifparse.cc:396:parse_blif$200590.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202070.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202174.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202277.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202380.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202482.A1`
mmio_wdata[3]1041/work/rtl/top/e1_chip_top.sv:32.18-32.28mmio_write_data_fanout`$abc$197552$auto$blifparse.cc:396:parse_blif$200713.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202073.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202177.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202280.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202383.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202485.A1`
$abc$197552$new_n110601031generated/no source attributesynthesis_generated_logic`$abc$197552$auto$blifparse.cc:396:parse_blif$200153.B
$abc$197552$auto$blifparse.cc:396:parse_blif$204071.B1
$abc$197552$auto$blifparse.cc:396:parse_blif$221674.S
$abc$197552$auto$blifparse.cc:396:parse_blif$221675.S
$abc$197552$auto$blifparse.cc:396:parse_blif$221676.S
$abc$197552$auto$blifparse.cc:396:parse_blif$221677.S`
mmio_wdata[8]1031/work/rtl/top/e1_chip_top.sv:32.18-32.28mmio_write_data_fanout`$abc$197552$auto$blifparse.cc:396:parse_blif$201296.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202088.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202192.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202295.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202398.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202500.A1`
mmio_wdata[9]1031/work/rtl/top/e1_chip_top.sv:32.18-32.28mmio_write_data_fanout`$abc$197552$auto$blifparse.cc:396:parse_blif$201342.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202091.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202195.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202298.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202401.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202503.A1`
mmio_wdata[17]1031/work/rtl/top/e1_chip_top.sv:32.18-32.28mmio_write_data_fanout`$abc$197552$auto$blifparse.cc:396:parse_blif$201635.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202115.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202219.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202322.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202425.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202527.A1`
mmio_wdata[16]1021/work/rtl/top/e1_chip_top.sv:32.18-32.28mmio_write_data_fanout`$abc$197552$auto$blifparse.cc:396:parse_blif$197565.A
$abc$197552$auto$blifparse.cc:396:parse_blif$201604.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202112.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202216.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202319.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202422.A1`
mmio_wdata[4]1021/work/rtl/top/e1_chip_top.sv:32.18-32.28mmio_write_data_fanout`$abc$197552$auto$blifparse.cc:396:parse_blif$200836.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202076.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202180.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202283.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202386.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202488.A1`
mmio_wdata[5]1021/work/rtl/top/e1_chip_top.sv:32.18-32.28mmio_write_data_fanout`$abc$197552$auto$blifparse.cc:396:parse_blif$200971.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202079.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202183.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202286.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202389.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202491.A1`
mmio_wdata[18]1021/work/rtl/top/e1_chip_top.sv:32.18-32.28mmio_write_data_fanout`$abc$197552$auto$blifparse.cc:396:parse_blif$201663.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202118.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202222.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202325.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202428.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202530.A1`
mmio_wdata[6]1011/work/rtl/top/e1_chip_top.sv:32.18-32.28mmio_write_data_fanout`$abc$197552$auto$blifparse.cc:396:parse_blif$201112.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202082.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202186.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202289.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202392.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202494.A1`
mmio_wdata[7]1011/work/rtl/top/e1_chip_top.sv:32.18-32.28mmio_write_data_fanout`$abc$197552$auto$blifparse.cc:396:parse_blif$201250.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202085.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202189.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202292.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202395.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202497.A1`
mmio_wdata[10]1011/work/rtl/top/e1_chip_top.sv:32.18-32.28mmio_write_data_fanout`$abc$197552$auto$blifparse.cc:396:parse_blif$201385.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202094.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202198.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202301.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202404.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202506.A1`
mmio_wdata[11]1011/work/rtl/top/e1_chip_top.sv:32.18-32.28mmio_write_data_fanout`$abc$197552$auto$blifparse.cc:396:parse_blif$201427.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202097.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202201.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202304.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202407.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202509.A1`
mmio_wdata[12]1011/work/rtl/top/e1_chip_top.sv:32.18-32.28mmio_write_data_fanout`$abc$197552$auto$blifparse.cc:396:parse_blif$201469.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202100.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202204.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202307.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202410.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202512.A1`
mmio_wdata[13]1011/work/rtl/top/e1_chip_top.sv:32.18-32.28mmio_write_data_fanout`$abc$197552$auto$blifparse.cc:396:parse_blif$201503.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202103.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202207.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202310.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202413.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202515.A1`
mmio_wdata[19]1011/work/rtl/top/e1_chip_top.sv:32.18-32.28mmio_write_data_fanout`$abc$197552$auto$blifparse.cc:396:parse_blif$201689.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202121.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202225.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202328.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202431.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202533.A1`
mmio_wdata[20]1011/work/rtl/top/e1_chip_top.sv:32.18-32.28mmio_write_data_fanout`$abc$197552$auto$blifparse.cc:396:parse_blif$201723.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202124.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202228.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202331.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202434.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202536.A1`
mmio_wdata[21]1011/work/rtl/top/e1_chip_top.sv:32.18-32.28mmio_write_data_fanout`$abc$197552$auto$blifparse.cc:396:parse_blif$201752.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202127.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202231.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202334.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202437.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202539.A1`
mmio_wdata[14]1001/work/rtl/top/e1_chip_top.sv:32.18-32.28mmio_write_data_fanout`$abc$197552$auto$blifparse.cc:396:parse_blif$201541.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202106.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202210.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202313.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202416.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202518.A1`
mmio_wdata[15]1001/work/rtl/top/e1_chip_top.sv:32.18-32.28mmio_write_data_fanout`$abc$197552$auto$blifparse.cc:396:parse_blif$201571.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202109.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202213.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202316.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202419.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202521.A1`
mmio_wdata[26]1001/work/rtl/top/e1_chip_top.sv:32.18-32.28mmio_write_data_fanout`$abc$197552$auto$blifparse.cc:396:parse_blif$201909.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202142.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202246.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202349.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202452.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202554.A1`
mmio_wdata[27]1001/work/rtl/top/e1_chip_top.sv:32.18-32.28mmio_write_data_fanout`$abc$197552$auto$blifparse.cc:396:parse_blif$201938.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202145.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202249.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202352.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202455.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202557.A1`
mmio_wdata[28]1001/work/rtl/top/e1_chip_top.sv:32.18-32.28mmio_write_data_fanout`$abc$197552$auto$blifparse.cc:396:parse_blif$201972.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202148.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202252.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202355.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202458.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202560.A1`
mmio_wdata[29]1001/work/rtl/top/e1_chip_top.sv:32.18-32.28mmio_write_data_fanout`$abc$197552$auto$blifparse.cc:396:parse_blif$202006.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202151.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202255.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202358.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202461.A1
$abc$197552$auto$blifparse.cc:396:parse_blif$202563.A1`

Workstream Assignments

  1. Reset tree subagent: replace the single SoC reset distribution with module-local reset branches or a PD reset-tree strategy, then rerun OpenLane and confirm no [DRT-0120] reset net remains.
  2. MMIO/data fanout subagent: reduce write-data broadcast pressure by staging debug MMIO write data near register banks or by narrowing decoded write strobes per target.
  3. NPU/generated-logic subagent: inspect ABC-generated hotspots without source attributes, correlate sink clusters to rtl/npu/e1_npu.sv, and split wide mux/decode cones if they remain above threshold after reset fixes.
  4. PD constraints subagent: evaluate OpenROAD reset buffering constraints or custom post-synthesis repair scripts before declaring RTL-level reset replication necessary.

Notes

  • Clock fanout is reported separately and should be handled by CTS.
  • This report is diagnostic evidence, not release signoff. A clean route still needs antenna, STA/DRV, LVS/DRC, and full signoff gates closed.