Re: [PATCH net] net: systemport: set dev->max_mtu to UMAC_MAX_MTU_SIZE

From: Vladimir Oltean <olteanv@gmail.com>
To: Florian Fainelli <f.fainelli@gmail.com>
Cc: netdev@vger.kernel.org, andrew@lunn.ch,
	"David S. Miller" <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>,
	Murali Krishna Policharla <murali.policharla@broadcom.com>,
	Vladimir Oltean <vladimir.oltean@nxp.com>,
	"open list:BROADCOM SYSTEMPORT ETHERNET DRIVER" 
	<bcm-kernel-feedback-list@broadcom.com>,
	open list <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH net] net: systemport: set dev->max_mtu to UMAC_MAX_MTU_SIZE
Date: Fri, 18 Dec 2020 22:24:41 +0200	[thread overview]
Message-ID: <20201218202441.ppcxswvlix3xszsn@skbuf> (raw)
In-Reply-To: <20201218173843.141046-1-f.fainelli@gmail.com>

Hi Florian,

On Fri, Dec 18, 2020 at 09:38:43AM -0800, Florian Fainelli wrote:
> The driver is already allocating receive buffers of 2KiB and the
> Ethernet MAC is configured to accept frames up to UMAC_MAX_MTU_SIZE.
> 
> Fixes: bfcb813203e6 ("net: dsa: configure the MTU for switch ports")
> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
> ---
>  drivers/net/ethernet/broadcom/bcmsysport.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/net/ethernet/broadcom/bcmsysport.c b/drivers/net/ethernet/broadcom/bcmsysport.c
> index 0fdd19d99d99..b1ae9eb8f247 100644
> --- a/drivers/net/ethernet/broadcom/bcmsysport.c
> +++ b/drivers/net/ethernet/broadcom/bcmsysport.c
> @@ -2577,6 +2577,7 @@ static int bcm_sysport_probe(struct platform_device *pdev)
>  			 NETIF_F_HW_VLAN_CTAG_TX;
>  	dev->hw_features |= dev->features;
>  	dev->vlan_features |= dev->features;
> +	dev->max_mtu = UMAC_MAX_MTU_SIZE;
>  
>  	/* Request the WOL interrupt and advertise suspend if available */
>  	priv->wol_irq_disabled = 1;
> -- 
> 2.25.1
> 

Do you want to treat the SYSTEMPORT Lite differently?

	/* Set maximum frame length */
	if (!priv->is_lite)
		umac_writel(priv, UMAC_MAX_MTU_SIZE, UMAC_MAX_FRAME_LEN);
	else
		gib_set_pad_extension(priv);