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 | 67 +++++++++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 76 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..4ee7c260a8a9
--- /dev/null
+++ b/net/dsa/tag_xrs700x.c
@@ -0,0 +1,67 @@
+// 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);
+ u8 *trailer;
+
+ trailer = skb_put(skb, 1);
+ trailer[0] = BIT(dp->index);
+
+ return skb;
+}
+
+static struct sk_buff *xrs700x_rcv(struct sk_buff *skb, struct net_device *dev,
+ struct packet_type *pt)
+{
+ int source_port;
+ u8 *trailer;
+
+ if (skb_linearize(skb))
+ return NULL;
+
+ trailer = skb_tail_pointer(skb) - 1;
+
+ source_port = ffs((int)trailer[0]) - 1;
+
+ if (source_port < 0)
+ return NULL;
+
+ skb->dev = dsa_master_find_slave(dev, 0, source_port);
+ if (!skb->dev)
+ return NULL;
+
+ if (pskb_trim_rcsum(skb, skb->len - 1))
+ return NULL;
+
+ /* Frame is forwarded by hardware, don't forward in software. */
+ skb->offload_fwd_mark = 1;
+
+ return skb;
+}
+
+static const struct dsa_device_ops xrs700x_netdev_ops = {
+ .name = "xrs700x",
+ .proto = DSA_TAG_PROTO_XRS700X,
+ .xmit = xrs700x_xmit,
+ .rcv = xrs700x_rcv,
+ .overhead = 1,
+ .tail_tag = true,
+};
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_XRS700X);
+
+module_dsa_tag_driver(xrs700x_netdev_ops);
--
2.11.0
