hw: Allow collectives with NoLoopback - #239
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The datapath already handles multicast with loopback disabled: the own-input crosspoint is tied off and `expected_handshakes` excludes the own-input route. Drop the SupportLoopback assertion so that routers whose endpoint never initiates collectives can disable loopback, and document the semantics in the NoLoopback parameter. Also fix a few typos in comments. Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
Lore0599
approved these changes
Oct 1, 2026
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This PR does two things:
Routers whose endpoint never initiates collectives can now set
NoLoopback=1. WithNoLoopback=1, a collective copy addressed to the flit's own input port is dropped; this is documented in the parameter doc.Also fixes typos in comments.
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