Re: [PATCH net-next V2] eth: fbnic: Configure RDE settings for pause frame

[Andrew Lunn]

On Thu, Nov 13, 2025 at 03:26:10PM -0800, Mohsin Bashir wrote:
> fbnic supports pause frames. When pause frames are enabled presumably
> user expects lossless operation from the NIC. Make sure we configure
> RDE (Rx DMA Engine) to DROP_NEVER mode to avoid discards due to delays
> in fetching Rx descriptors from the host.
> 
> While at it enable DROP_NEVER when NIC only has a single queue
> configured. In this case the NIC acts as a FIFO so there's no risk
> of head-of-line blocking other queues by making RDE wait. If pause
> is disabled this just moves the packet loss from the DMA engine to
> the Rx buffer.
> 
> Remove redundant call to fbnic_config_drop_mode_rcq(), introduced by
> commit 0cb4c0a13723 ("eth: fbnic: Implement Rx queue
> alloc/start/stop/free"). This call does not add value as
> fbnic_enable_rcq(), which is called immediately afterward, already
> handles this.
> 
> Although we do not support autoneg at this time, preserve tx_pause in
> .mac_link_up instead of fbnic_phylink_get_pauseparam()
> 
> Signed-off-by: Mohsin Bashir <mohsin.bashr@xxxxxxxxx>

Reviewed-by: Andrew Lunn <andrew@xxxxxxx>

    Andrew