lkml.org 
[lkml]   [2022]   [Apr]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [net-next v2 02/12] net: dsa: add Renesas RZ/N1 switch tag driver
From
On 4/29/22 07:34, Clément Léger wrote:
> The switch that is present on the Renesas RZ/N1 SoC uses a specific
> VLAN value followed by 6 bytes which contains forwarding configuration.
>
> Signed-off-by: Clément Léger <clement.leger@bootlin.com>
> ---

[snip]

> +struct a5psw_tag {
> + __be16 ctrl_tag;
> + __be16 ctrl_data;
> + __be16 ctrl_data2_hi;
> + __be16 ctrl_data2_lo;
> +} __packed;

The structure should already be naturally aligned.

> +
> +static struct sk_buff *a5psw_tag_xmit(struct sk_buff *skb, struct net_device *dev)
> +{
> + struct dsa_port *dp = dsa_slave_to_port(dev);
> + struct a5psw_tag *ptag;
> + u32 data2_val;
> +
> + BUILD_BUG_ON(sizeof(*ptag) != A5PSW_TAG_LEN);
> +
> + /* The Ethernet switch we are interfaced with needs packets to be at
> + * least 64 bytes (including FCS) otherwise they will be discarded when
> + * they enter the switch port logic. When tagging is enabled, we need
> + * to make sure that packets are at least 68 bytes (including FCS and
> + * tag).

Did you mean 70 bytes since your tag is 6, and not 4 bytes?
--
Florian

\
 
 \ /
  Last update: 2022-04-29 18:24    [W:0.086 / U:0.432 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site