fe28c53ed7
The Synopsys TSN MAC supports Qbv base times in the past, but only up to a
certain limit. As a result, a taprio qdisc configuration with a small
base time (for example when treating the base time as a simple phase
offset) is not applied by the hardware and silently ignored.
This was observed on an NXP i.MX8MPlus device, but likely affects all
TSN-variants of the MAC.
Fix the issue by making sure the base time is in the future, pushing it by
an integer amount of cycle times if needed. (a similar check is already
done in several other taprio implementations, see for example
drivers/net/ethernet/intel/igc/igc_tsn.c#L116 or
drivers/net/dsa/sja1105/sja1105_ptp.h#L39).
Fixes: b60189e0392f ("net: stmmac: Integrate EST with TAPRIO scheduler API")
Signed-off-by: Yannick Vignon <yannick.vignon@nxp.com>
Link: https://lore.kernel.org/r/20210113131557.24651-2-yannick.vignon@oss.nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.