Wait a bit before issuing the first i2c transaction to tofino #2325
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nathanaelhuffman
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labbott
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Dec 16, 2025
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At initial power up, it is possible to beat the internal (unspecifed) initialization and issue i2c transactions via the FPGA resulting in i2c NACKs from the tofino and an un-usable system state. I've written more details in #2326 about better possible fixes, but this works around the issue and gets us going in manufacturing.
It is also possible to see this failure mode in field systems after the #2298 software patch, but we'd only notice on a cold-sequence vs a warm sequence where the Tofino is up.