On Fri, Nov 20, 2020 at 12:58 PM Andrew Lunn <andrew@xxxxxxx> wrote:
>
> 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.
Done and tested. Thanks
>
> Andrew
