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ns8250: Fix sense of LSR_TEMT FCR check
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Authored by cperciva on Oct 28 2022, 4:45 AM.
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Details

Summary

When flushing the UART, we need to drain manually if LSR_TEMT is
*not* asserted, aka. if the transmit FIFO is not empty.

Reported by: void <void@f-m.fm>
Fixes: c4b68e7e53bb "ns8250: Check if flush via FCR succeeded"

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rG FreeBSD src repository
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cperciva created this revision.

Tested by "void", confirmed that this eliminates the warning from his bhyve VMs.

This revision was not accepted when it landed; it landed in state Needs Review.Oct 28 2022, 7:21 PM
This revision was automatically updated to reflect the committed changes.