On Fri, Nov 20, 2020 at 12:16:25PM -0600, George McCollister wrote:
> Add support for Arrow SpeedChips XRS700x single byte tag trailer. This
> is modeled on tag_trailer.c which works in a similar way.
>
> Signed-off-by: George McCollister <george.mccollister@xxxxxxxxx>
> ---
> include/net/dsa.h | 2 ++
> net/dsa/Kconfig | 6 ++++
> net/dsa/Makefile | 1 +
> net/dsa/tag_xrs700x.c | 91 +++++++++++++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 100 insertions(+)
> create mode 100644 net/dsa/tag_xrs700x.c
>
> diff --git a/include/net/dsa.h b/include/net/dsa.h
> index 2e64e8de4631..eb46ecdcf165 100644
> --- a/include/net/dsa.h
> +++ b/include/net/dsa.h
> @@ -46,6 +46,7 @@ struct phylink_link_state;
> #define DSA_TAG_PROTO_AR9331_VALUE 16
> #define DSA_TAG_PROTO_RTL4_A_VALUE 17
> #define DSA_TAG_PROTO_HELLCREEK_VALUE 18
> +#define DSA_TAG_PROTO_XRS700X_VALUE 19
>
> enum dsa_tag_protocol {
> DSA_TAG_PROTO_NONE = DSA_TAG_PROTO_NONE_VALUE,
> @@ -67,6 +68,7 @@ enum dsa_tag_protocol {
> DSA_TAG_PROTO_AR9331 = DSA_TAG_PROTO_AR9331_VALUE,
> DSA_TAG_PROTO_RTL4_A = DSA_TAG_PROTO_RTL4_A_VALUE,
> DSA_TAG_PROTO_HELLCREEK = DSA_TAG_PROTO_HELLCREEK_VALUE,
> + DSA_TAG_PROTO_XRS700X = DSA_TAG_PROTO_XRS700X_VALUE,
> };
>
> struct packet_type;
> diff --git a/net/dsa/Kconfig b/net/dsa/Kconfig
> index dfecd7b22fd7..2d226a5c085f 100644
> --- a/net/dsa/Kconfig
> +++ b/net/dsa/Kconfig
> @@ -139,4 +139,10 @@ config NET_DSA_TAG_TRAILER
> Say Y or M if you want to enable support for tagging frames at
> with a trailed. e.g. Marvell 88E6060.
>
> +config NET_DSA_TAG_XRS700X
> + tristate "Tag driver for XRS700x switches"
> + help
> + Say Y or M if you want to enable support for tagging frames for
> + Arrow SpeedChips XRS700x switches that use a single byte tag trailer.
> +
> endif
> diff --git a/net/dsa/Makefile b/net/dsa/Makefile
> index 0fb2b75a7ae3..92cea2132241 100644
> --- a/net/dsa/Makefile
> +++ b/net/dsa/Makefile
> @@ -18,3 +18,4 @@ obj-$(CONFIG_NET_DSA_TAG_OCELOT) += tag_ocelot.o
> obj-$(CONFIG_NET_DSA_TAG_QCA) += tag_qca.o
> obj-$(CONFIG_NET_DSA_TAG_SJA1105) += tag_sja1105.o
> obj-$(CONFIG_NET_DSA_TAG_TRAILER) += tag_trailer.o
> +obj-$(CONFIG_NET_DSA_TAG_XRS700X) += tag_xrs700x.o
> diff --git a/net/dsa/tag_xrs700x.c b/net/dsa/tag_xrs700x.c
> new file mode 100644
> index 000000000000..2eda57a4a474
> --- /dev/null
> +++ b/net/dsa/tag_xrs700x.c
> @@ -0,0 +1,91 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * XRS700x tag format handling
> + * Copyright (c) 2008-2009 Marvell Semiconductor
> + * Copyright (c) 2020 NovaTech LLC
> + */
> +
> +#include <linux/etherdevice.h>
> +#include <linux/list.h>
> +#include <linux/slab.h>
> +#include <linux/bitops.h>
> +
> +#include "dsa_priv.h"
> +
> +static struct sk_buff *xrs700x_xmit(struct sk_buff *skb, struct net_device *dev)
> +{
> + struct dsa_port *dp = dsa_slave_to_port(dev);
> + struct sk_buff *nskb;
> + int padlen;
> + u8 *trailer;
> +
> + /* We have to make sure that the trailer ends up as the very
> + * last byte of the packet. This means that we have to pad
> + * the packet to the minimum ethernet frame size, if necessary,
> + * before adding the trailer.
> + */
> + padlen = 0;
> + if (skb->len < 63)
> + padlen = 63 - skb->len;
> +
> + nskb = alloc_skb(NET_IP_ALIGN + skb->len + padlen + 1, GFP_ATOMIC);
> + if (!nskb)
> + return NULL;
> + skb_reserve(nskb, NET_IP_ALIGN);
Hi George
This needs updating to take into account:
commit a3b0b6479700a5b0af2c631cb2ec0fb7a0d978f2
Author: Vladimir Oltean <vladimir.oltean@xxxxxxx>
Date: Sun Nov 1 21:16:09 2020 +0200
net: dsa: implement a central TX reallocation procedure
which i think will handle the padding for you.
Andrew
