| Message ID | 20200711203206.1110108-3-andrew@lunn.ch |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
| Series | Fix MTU warnings for fec/mv886xxx combo | expand |
diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c index 9f80a33c5b16..8047dda947f2 100644 --- a/drivers/net/ethernet/freescale/fec_main.c +++ b/drivers/net/ethernet/freescale/fec_main.c @@ -3710,6 +3710,8 @@ fec_probe(struct platform_device *pdev) fec_enet_clk_enable(ndev, false); pinctrl_pm_select_sleep_state(&pdev->dev); + ndev->max_mtu = PKT_MAXBUF_SIZE - ETH_HLEN - ETH_FCS_LEN; + ret = register_netdev(ndev); if (ret) goto failed_register;
The FEC allocates 2K buffers, but looses some of it due to alignment. It can however support an MTU bigger than the default. This is particularly interesting when used in combination with Ethernet switches supporting DSA, which have extra headers. The DSA core will try to increase the MTU to support these extra headers. If the max size defaults to that of standard Ethernet we get a warning. By setting the max to what the driver actually supports, we avoid this warning. Signed-off-by: Andrew Lunn <andrew@lunn.ch> --- drivers/net/ethernet/freescale/fec_main.c | 2 ++ 1 file changed, 2 insertions(+)