[PATCH net-next v8 1/8] net: dsa: Add tag handling for Hirschmann Hellcreek switches
From: Kurt Kanzenbach <kurt@linutronix.de>
Date: 2020-11-03 07:11:39
Also in:
linux-devicetree
Subsystem:
hirschmann hellcreek ethernet switch driver, networking [dsa], networking [general], the rest · Maintainers:
Kurt Kanzenbach, Andrew Lunn, Vladimir Oltean, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
The Hirschmann Hellcreek TSN switches have a special tagging protocol for frames exchanged between the CPU port and the master interface. The format is a one byte trailer indicating the destination or origin port. It's quite similar to the Micrel KSZ tagging. That's why the implementation is based on that code. Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de> --- include/net/dsa.h | 2 ++ net/dsa/Kconfig | 6 ++++ net/dsa/Makefile | 1 + net/dsa/tag_hellcreek.c | 66 +++++++++++++++++++++++++++++++++++++++++ 4 files changed, 75 insertions(+) create mode 100644 net/dsa/tag_hellcreek.c
diff --git a/include/net/dsa.h b/include/net/dsa.h
index 35429a140dfa..04e93bafb7bd 100644
--- a/include/net/dsa.h
+++ b/include/net/dsa.h@@ -45,6 +45,7 @@ struct phylink_link_state; #define DSA_TAG_PROTO_OCELOT_VALUE 15 #define DSA_TAG_PROTO_AR9331_VALUE 16 #define DSA_TAG_PROTO_RTL4_A_VALUE 17 +#define DSA_TAG_PROTO_HELLCREEK_VALUE 18 enum dsa_tag_protocol { DSA_TAG_PROTO_NONE = DSA_TAG_PROTO_NONE_VALUE,
@@ -65,6 +66,7 @@ enum dsa_tag_protocol { DSA_TAG_PROTO_OCELOT = DSA_TAG_PROTO_OCELOT_VALUE, 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, }; struct packet_type;
diff --git a/net/dsa/Kconfig b/net/dsa/Kconfig
index 1f9b9b11008c..d975614f7dd6 100644
--- a/net/dsa/Kconfig
+++ b/net/dsa/Kconfig@@ -56,6 +56,12 @@ config NET_DSA_TAG_BRCM_PREPEND Broadcom switches which places the tag before the Ethernet header (prepended). +config NET_DSA_TAG_HELLCREEK + tristate "Tag driver for Hirschmann Hellcreek TSN switches" + help + Say Y or M if you want to enable support for tagging frames + for the Hirschmann Hellcreek TSN switches. + config NET_DSA_TAG_GSWIP tristate "Tag driver for Lantiq / Intel GSWIP switches" help
diff --git a/net/dsa/Makefile b/net/dsa/Makefile
index 4f47b2025ff5..e25d5457964a 100644
--- a/net/dsa/Makefile
+++ b/net/dsa/Makefile@@ -10,6 +10,7 @@ obj-$(CONFIG_NET_DSA_TAG_BRCM_COMMON) += tag_brcm.o obj-$(CONFIG_NET_DSA_TAG_DSA) += tag_dsa.o obj-$(CONFIG_NET_DSA_TAG_EDSA) += tag_edsa.o obj-$(CONFIG_NET_DSA_TAG_GSWIP) += tag_gswip.o +obj-$(CONFIG_NET_DSA_TAG_HELLCREEK) += tag_hellcreek.o obj-$(CONFIG_NET_DSA_TAG_KSZ) += tag_ksz.o obj-$(CONFIG_NET_DSA_TAG_RTL4_A) += tag_rtl4_a.o obj-$(CONFIG_NET_DSA_TAG_LAN9303) += tag_lan9303.o
diff --git a/net/dsa/tag_hellcreek.c b/net/dsa/tag_hellcreek.c
new file mode 100644
index 000000000000..2061de06eafb
--- /dev/null
+++ b/net/dsa/tag_hellcreek.c@@ -0,0 +1,66 @@ +// SPDX-License-Identifier: (GPL-2.0 OR MIT) +/* + * net/dsa/tag_hellcreek.c - Hirschmann Hellcreek switch tag format handling + * + * Copyright (C) 2019,2020 Linutronix GmbH + * Author Kurt Kanzenbach <kurt@linutronix.de> + * + * Based on tag_ksz.c. + */ + +#include <linux/etherdevice.h> +#include <linux/list.h> +#include <linux/slab.h> +#include <net/dsa.h> + +#include "dsa_priv.h" + +#define HELLCREEK_TAG_LEN 1 + +static struct sk_buff *hellcreek_xmit(struct sk_buff *skb, + struct net_device *dev) +{ + struct dsa_port *dp = dsa_slave_to_port(dev); + u8 *tag; + + /* Tag encoding */ + tag = skb_put(skb, HELLCREEK_TAG_LEN); + *tag = BIT(dp->index); + + return skb; +} + +static struct sk_buff *hellcreek_rcv(struct sk_buff *skb, + struct net_device *dev, + struct packet_type *pt) +{ + /* Tag decoding */ + u8 *tag = skb_tail_pointer(skb) - HELLCREEK_TAG_LEN; + unsigned int port = tag[0] & 0x03; + + skb->dev = dsa_master_find_slave(dev, 0, port); + if (!skb->dev) { + netdev_warn(dev, "Failed to get source port: %d\n", port); + return NULL; + } + + pskb_trim_rcsum(skb, skb->len - HELLCREEK_TAG_LEN); + + skb->offload_fwd_mark = true; + + return skb; +} + +static const struct dsa_device_ops hellcreek_netdev_ops = { + .name = "hellcreek", + .proto = DSA_TAG_PROTO_HELLCREEK, + .xmit = hellcreek_xmit, + .rcv = hellcreek_rcv, + .overhead = HELLCREEK_TAG_LEN, + .tail_tag = true, +}; + +MODULE_LICENSE("Dual MIT/GPL"); +MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_HELLCREEK); + +module_dsa_tag_driver(hellcreek_netdev_ops);
--
2.20.1