Re: [PATCH net-next] net: fec: support RX flushing via an ethtool private flag

[Paolo Abeni <pabeni@redhat.com>]

On 8/25/26 11:19 AM, A. Sverdlin wrote:
> From: Alexander Sverdlin <alexander.sverdlin@siemens.com>
> 
> The FEC controller can flush the RX FIFO of an individual receive queue
> through the RX_FLUSHn bits of the FEC_QOS_SCHEME (ENET_QOS) register.
> 
> RX flushing prevents frames in the RX FIFO from being blocked. Blocking
> can occur when the frame at the head of the RX FIFO cannot be forwarded
> because the ring it is associated with cannot accept it, i.e. when the
> ring's RxBD[EMPTY] is not set or ENET_RDARn is not set. When RX flushing
> is enabled for a ring, such a blocking frame is flushed (discarded)
> instead of stalling the FIFO and holding up the other rings.
> 
> Expose this per-queue capability as a runtime ethtool private flag
> ("rx-flush-qN").
> 
> Due to erratum ERR050395 (observed e.g. on i.MX8QXP), enabling RX flushing
> on more than one queue at a time can lock up the receive path, so only a
> single queue may have flushing enabled.
> 
> Signed-off-by: Alexander Sverdlin <alexander.sverdlin@siemens.com>
## Form letter - net-next-closed

net-next pull request for v7.3 has already been merged, and therefore
the net-next tree is closed for new drivers, features, code refactoring
and optimizations. We are currently accepting bug fixes only.

Please repost when net-next reopens after Aug 31st.

RFC patches sent for review only are obviously welcome at any time.

See:
https://www.kernel.org/doc/html/next/process/maintainer-netdev.html#development-cycle
-- 
pw-bot: defer
pv-bot: closed