297c4de6f7
Commit316bcffe44("net: dsa: felix: disable always guard band bit for TAS config") disabled the guard band and broke 802.3Qbv compliance. There are two issues here: (1) Without the guard band the end of the scheduling window could be overrun by a frame in transit. (2) Frames that don't fit into a configured window will still be sent. The reason for both issues is that the switch will schedule the _start_ of a frame transmission inside the predefined window without taking the length of the frame into account. Thus, we'll need the guard band which will close the gate early, so that a complete frame can still be sent. Revert the commit and add a note. For a lengthy discussion see [1]. [1] https://lore.kernel.org/netdev/c7618025da6723418c56a54fe4683bd7@walle.cc/ Fixes:316bcffe44("net: dsa: felix: disable always guard band bit for TAS config") Signed-off-by: Michael Walle <michael@walle.cc> Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Linux kernel
============
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In order to build the documentation, use ``make htmldocs`` or
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There are various text files in the Documentation/ subdirectory,
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the problems which may result by upgrading your kernel.