net: dsa: Add Lantiq / Intel GSWIP tag support

This handles the tag added by the PMAC on the VRX200 SoC line.

The GSWIP uses internally a GSWIP special tag which is located after the
Ethernet header. The PMAC which connects the GSWIP to the CPU converts
this special tag used by the GSWIP into the PMAC special tag which is
added in front of the Ethernet header.

This was tested with GSWIP 2.1 found in the VRX200 SoCs, other GSWIP
versions use slightly different PMAC special tags.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/MAINTAINERS b/MAINTAINERS
index 0b2e27e..a11fbbe 100644 (file)
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8167,6 +8167,12 @@ S:       Maintained
 F:     net/l3mdev
 F:     include/net/l3mdev.h
 
+LANTIQ / INTEL Ethernet drivers
+M:     Hauke Mehrtens <hauke@hauke-m.de>
+L:     netdev@vger.kernel.org
+S:     Maintained
+F:     net/dsa/tag_gswip.c
+
 LANTIQ MIPS ARCHITECTURE
 M:     John Crispin <john@phrozen.org>
 L:     linux-mips@linux-mips.org

diff --git a/include/net/dsa.h b/include/net/dsa.h
index 461e8a7..23690c4 100644 (file)
--- a/include/net/dsa.h
+++ b/include/net/dsa.h
@@ -35,6 +35,7 @@ enum dsa_tag_protocol {
        DSA_TAG_PROTO_BRCM_PREPEND,
        DSA_TAG_PROTO_DSA,
        DSA_TAG_PROTO_EDSA,
+       DSA_TAG_PROTO_GSWIP,
        DSA_TAG_PROTO_KSZ,
        DSA_TAG_PROTO_LAN9303,
        DSA_TAG_PROTO_MTK,

diff --git a/net/dsa/Kconfig b/net/dsa/Kconfig
index 4183e4b..48c4191 100644 (file)
--- a/net/dsa/Kconfig
+++ b/net/dsa/Kconfig
@@ -38,6 +38,9 @@ config NET_DSA_TAG_DSA
 config NET_DSA_TAG_EDSA
        bool
 
+config NET_DSA_TAG_GSWIP
+       bool
+
 config NET_DSA_TAG_KSZ
        bool
 

diff --git a/net/dsa/Makefile b/net/dsa/Makefile
index 9e4d353..6e721f7 100644 (file)
--- a/net/dsa/Makefile
+++ b/net/dsa/Makefile
@@ -9,6 +9,7 @@ dsa_core-$(CONFIG_NET_DSA_TAG_BRCM) += tag_brcm.o
 dsa_core-$(CONFIG_NET_DSA_TAG_BRCM_PREPEND) += tag_brcm.o
 dsa_core-$(CONFIG_NET_DSA_TAG_DSA) += tag_dsa.o
 dsa_core-$(CONFIG_NET_DSA_TAG_EDSA) += tag_edsa.o
+dsa_core-$(CONFIG_NET_DSA_TAG_GSWIP) += tag_gswip.o
 dsa_core-$(CONFIG_NET_DSA_TAG_KSZ) += tag_ksz.o
 dsa_core-$(CONFIG_NET_DSA_TAG_LAN9303) += tag_lan9303.o
 dsa_core-$(CONFIG_NET_DSA_TAG_MTK) += tag_mtk.o

diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c
index 45f7085..5f73e96 100644 (file)
--- a/net/dsa/dsa.c
+++ b/net/dsa/dsa.c
@@ -52,6 +52,9 @@ const struct dsa_device_ops *dsa_device_ops[DSA_TAG_LAST] = {
 #ifdef CONFIG_NET_DSA_TAG_EDSA
        [DSA_TAG_PROTO_EDSA] = &edsa_netdev_ops,
 #endif
+#ifdef CONFIG_NET_DSA_TAG_GSWIP
+       [DSA_TAG_PROTO_GSWIP] = &gswip_netdev_ops,
+#endif
 #ifdef CONFIG_NET_DSA_TAG_KSZ
        [DSA_TAG_PROTO_KSZ] = &ksz_netdev_ops,
 #endif

diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h
index 2868b5b..9e4fd04 100644 (file)
--- a/net/dsa/dsa_priv.h
+++ b/net/dsa/dsa_priv.h
@@ -206,6 +206,9 @@ extern const struct dsa_device_ops dsa_netdev_ops;
 /* tag_edsa.c */
 extern const struct dsa_device_ops edsa_netdev_ops;
 
+/* tag_gswip.c */
+extern const struct dsa_device_ops gswip_netdev_ops;
+
 /* tag_ksz.c */
 extern const struct dsa_device_ops ksz_netdev_ops;
 

diff --git a/net/dsa/tag_gswip.c b/net/dsa/tag_gswip.c
new file mode 100644 (file)
index 0000000..49e9b73
--- /dev/null
+++ b/net/dsa/tag_gswip.c
@@ -0,0 +1,109 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Intel / Lantiq GSWIP V2.0 PMAC tag support
+ *
+ * Copyright (C) 2017 - 2018 Hauke Mehrtens <hauke@hauke-m.de>
+ */
+
+#include <linux/bitops.h>
+#include <linux/etherdevice.h>
+#include <linux/skbuff.h>
+#include <net/dsa.h>
+
+#include "dsa_priv.h"
+
+#define GSWIP_TX_HEADER_LEN            4
+
+/* special tag in TX path header */
+/* Byte 0 */
+#define GSWIP_TX_SLPID_SHIFT           0       /* source port ID */
+#define  GSWIP_TX_SLPID_CPU            2
+#define  GSWIP_TX_SLPID_APP1           3
+#define  GSWIP_TX_SLPID_APP2           4
+#define  GSWIP_TX_SLPID_APP3           5
+#define  GSWIP_TX_SLPID_APP4           6
+#define  GSWIP_TX_SLPID_APP5           7
+
+/* Byte 1 */
+#define GSWIP_TX_CRCGEN_DIS            BIT(7)
+#define GSWIP_TX_DPID_SHIFT            0       /* destination group ID */
+#define  GSWIP_TX_DPID_ELAN            0
+#define  GSWIP_TX_DPID_EWAN            1
+#define  GSWIP_TX_DPID_CPU             2
+#define  GSWIP_TX_DPID_APP1            3
+#define  GSWIP_TX_DPID_APP2            4
+#define  GSWIP_TX_DPID_APP3            5
+#define  GSWIP_TX_DPID_APP4            6
+#define  GSWIP_TX_DPID_APP5            7
+
+/* Byte 2 */
+#define GSWIP_TX_PORT_MAP_EN           BIT(7)
+#define GSWIP_TX_PORT_MAP_SEL          BIT(6)
+#define GSWIP_TX_LRN_DIS               BIT(5)
+#define GSWIP_TX_CLASS_EN              BIT(4)
+#define GSWIP_TX_CLASS_SHIFT           0
+#define GSWIP_TX_CLASS_MASK            GENMASK(3, 0)
+
+/* Byte 3 */
+#define GSWIP_TX_DPID_EN               BIT(0)
+#define GSWIP_TX_PORT_MAP_SHIFT                1
+#define GSWIP_TX_PORT_MAP_MASK         GENMASK(6, 1)
+
+#define GSWIP_RX_HEADER_LEN    8
+
+/* special tag in RX path header */
+/* Byte 7 */
+#define GSWIP_RX_SPPID_SHIFT           4
+#define GSWIP_RX_SPPID_MASK            GENMASK(6, 4)
+
+static struct sk_buff *gswip_tag_xmit(struct sk_buff *skb,
+                                     struct net_device *dev)
+{
+       struct dsa_port *dp = dsa_slave_to_port(dev);
+       int err;
+       u8 *gswip_tag;
+
+       err = skb_cow_head(skb, GSWIP_TX_HEADER_LEN);
+       if (err)
+               return NULL;
+
+       skb_push(skb, GSWIP_TX_HEADER_LEN);
+
+       gswip_tag = skb->data;
+       gswip_tag[0] = GSWIP_TX_SLPID_CPU;
+       gswip_tag[1] = GSWIP_TX_DPID_ELAN;
+       gswip_tag[2] = GSWIP_TX_PORT_MAP_EN | GSWIP_TX_PORT_MAP_SEL;
+       gswip_tag[3] = BIT(dp->index + GSWIP_TX_PORT_MAP_SHIFT) & GSWIP_TX_PORT_MAP_MASK;
+       gswip_tag[3] |= GSWIP_TX_DPID_EN;
+
+       return skb;
+}
+
+static struct sk_buff *gswip_tag_rcv(struct sk_buff *skb,
+                                    struct net_device *dev,
+                                    struct packet_type *pt)
+{
+       int port;
+       u8 *gswip_tag;
+
+       if (unlikely(!pskb_may_pull(skb, GSWIP_RX_HEADER_LEN)))
+               return NULL;
+
+       gswip_tag = skb->data - ETH_HLEN;
+
+       /* Get source port information */
+       port = (gswip_tag[7] & GSWIP_RX_SPPID_MASK) >> GSWIP_RX_SPPID_SHIFT;
+       skb->dev = dsa_master_find_slave(dev, 0, port);
+       if (!skb->dev)
+               return NULL;
+
+       /* remove GSWIP tag */
+       skb_pull_rcsum(skb, GSWIP_RX_HEADER_LEN);
+
+       return skb;
+}
+
+const struct dsa_device_ops gswip_netdev_ops = {
+       .xmit = gswip_tag_xmit,
+       .rcv = gswip_tag_rcv,
+};