Re: [PATCH] remove vlan tags in CPSW dual emac mode

From: Mark Jackson <mpfj-list@newflow.co.uk>
To: Mugunthan V N <mugunthanvnm@ti.com>
Cc: Markus Brunner <systemprogrammierung.brunner@gmail.com>,
	netdev@vger.kernel.org, davem@davemloft.net,
	linux-arm-kernel@lists.infradead.org, linux-omap@vger.kernel.org
Subject: Re: [PATCH] remove vlan tags in CPSW dual emac mode
Date: Fri, 12 Jul 2013 14:57:03 +0100	[thread overview]
Message-ID: <51E00B2F.6050406@newflow.co.uk> (raw)
In-Reply-To: <5176C4FE.4080305@ti.com>

On 23/04/13 18:29, Mugunthan V N wrote:
> On 4/23/2013 9:48 PM, Markus Brunner wrote:
>> If operating in dual emac mode all packets sent by the CPSW contain vlan headers with the reserved VID 0,
>> which gets stripped away by all somewhat recent Linux versions. Operating systems without that behaviour will fail to communicate.
>> This patch fixes that behaviour by disabling the VLAN_AWARE mode as already described by the comment above.
>>
>> Signed-off-by: Markus Brunner <systemprogrammierung.brunner@gmail.com>
>> Tested-by: Mark Jackson <mpfj@newflow.co.uk>
>>
>> ---
>> --- linux-3.9-rc8.orig/drivers/net/ethernet/ti/cpsw.c    2013-04-23 17:26:11.000000000 +0200
>> +++ linux-3.9-rc8/drivers/net/ethernet/ti/cpsw.c    2013-04-23 17:36:25.000000000 +0200
>> @@ -751,9 +751,9 @@ static void cpsw_init_host_port(struct c
>>       /* switch to vlan unaware mode */
>>       cpsw_ale_control_set(priv->ale, priv->host_port, ALE_VLAN_AWARE,
>>                    CPSW_ALE_VLAN_AWARE);
>>       control_reg = readl(&priv->regs->control);
>> -    control_reg |= CPSW_VLAN_AWARE;
>> +    control_reg &= ~CPSW_VLAN_AWARE;
>>       writel(control_reg, &priv->regs->control);
>>       fifo_mode = (priv->data.dual_emac) ? CPSW_FIFO_DUAL_MAC_MODE :
>>                CPSW_FIFO_NORMAL_MODE;
>>       writel(fifo_mode, &priv->host_port_regs->tx_in_ctl);
> Disabling VLAN aware mode will enable switching mode and the feature of
> separating the two down stream port is lost with this patch
> Please check TRM for more info in *14.3.2.10.2 Dual Mac Mode* chapter

Just to update this (old) thread ...

I can still confirm that *without* the above patch, I am *unable* to use both network
ports on our AM335x board.

My .dts file contains:-

mac: ethernet@4a100000 {
	dual_emac = <1>;

	cpsw_emac0: slave@4a100200 {
		dual_emac_res_vlan = <1>;
	};

	cpsw_emac1: slave@4a100300 {
		dual_emac_res_vlan = <2>;
	};
};

&cpsw_emac0 {
	phy_id = <&davinci_mdio>, <0>;
};

&cpsw_emac1 {
	phy_id = <&davinci_mdio>, <1>;
};

My /etc/network/interfaces file is:-

auto lo eth0 eth1
iface lo inet loopback
iface eth0 inet static
address 10.0.101.3
netmask 255.255.0.0
gateway 10.0.0.1
iface eth1 inet static
address 10.1.101.3
netmask 255.255.0.0

So I'm not sure what's wrong, but it's *definitely* not correct.

Cheers
Mark J.