The NXP NETC switch tag is a proprietary header added to frames after the source MAC address. The switch tag has 3 types, and each type has 1 ~ 4 subtypes, the details are as follows. Forward NXP switch tag (Type=0): Represents forwarded frames. - SubType = 0 - Normal frame processing. To_Port NXP switch tag (Type=1): Represents frames that are to be sent to a specific switch port. - SubType = 0. No request to perform timestamping. - SubType = 1. Request to perform one-step timestamping. - SubType = 2. Request to perform two-step timestamping. - SubType = 3. Request to perform both one-step timestamping and two-step timestamping. To_Host NXP switch tag (Type=2): Represents frames redirected or copied to the switch management port. - SubType = 0. Received frames redirected or copied to the switch management port. - SubType = 1. Received frames redirected or copied to the switch management port with captured timestamp at the switch port where the frame was received. - SubType = 2. Transmit timestamp response (two-step timestamping). In addition, the length of different type switch tag is different, the minimum length is 6 bytes, the maximum length is 14 bytes. Currently, Forward tag, SubType 0 of To_Port tag and Subtype 0 of To_Host tag are supported. More tags will be supported in the future. Signed-off-by: Wei Fang --- include/linux/dsa/tag_netc.h | 14 +++ include/net/dsa.h | 2 + include/uapi/linux/if_ether.h | 1 + net/dsa/Kconfig | 10 ++ net/dsa/Makefile | 1 + net/dsa/tag_netc.c | 180 ++++++++++++++++++++++++++++++++++ 6 files changed, 208 insertions(+) create mode 100644 include/linux/dsa/tag_netc.h create mode 100644 net/dsa/tag_netc.c diff --git a/include/linux/dsa/tag_netc.h b/include/linux/dsa/tag_netc.h new file mode 100644 index 000000000000..fe964722e5b0 --- /dev/null +++ b/include/linux/dsa/tag_netc.h @@ -0,0 +1,14 @@ +/* SPDX-License-Identifier: GPL-2.0 + * + * Copyright 2025-2026 NXP + */ + +#ifndef __NET_DSA_TAG_NETC_H +#define __NET_DSA_TAG_NETC_H + +#include +#include + +#define NETC_TAG_MAX_LEN 14 + +#endif diff --git a/include/net/dsa.h b/include/net/dsa.h index 6c17446f3dcc..6bed824d1f07 100644 --- a/include/net/dsa.h +++ b/include/net/dsa.h @@ -58,6 +58,7 @@ struct tc_action; #define DSA_TAG_PROTO_YT921X_VALUE 30 #define DSA_TAG_PROTO_MXL_GSW1XX_VALUE 31 #define DSA_TAG_PROTO_MXL862_VALUE 32 +#define DSA_TAG_PROTO_NETC_VALUE 33 enum dsa_tag_protocol { DSA_TAG_PROTO_NONE = DSA_TAG_PROTO_NONE_VALUE, @@ -93,6 +94,7 @@ enum dsa_tag_protocol { DSA_TAG_PROTO_YT921X = DSA_TAG_PROTO_YT921X_VALUE, DSA_TAG_PROTO_MXL_GSW1XX = DSA_TAG_PROTO_MXL_GSW1XX_VALUE, DSA_TAG_PROTO_MXL862 = DSA_TAG_PROTO_MXL862_VALUE, + DSA_TAG_PROTO_NETC = DSA_TAG_PROTO_NETC_VALUE, }; struct dsa_switch; diff --git a/include/uapi/linux/if_ether.h b/include/uapi/linux/if_ether.h index df9d44a11540..fb5efc8e06cc 100644 --- a/include/uapi/linux/if_ether.h +++ b/include/uapi/linux/if_ether.h @@ -123,6 +123,7 @@ #define ETH_P_DSA_A5PSW 0xE001 /* A5PSW Tag Value [ NOT AN OFFICIALLY REGISTERED ID ] */ #define ETH_P_IFE 0xED3E /* ForCES inter-FE LFB type */ #define ETH_P_AF_IUCV 0xFBFB /* IBM af_iucv [ NOT AN OFFICIALLY REGISTERED ID ] */ +#define ETH_P_NXP_NETC 0xFD3A /* NXP NETC DSA [ NOT AN OFFICIALLY REGISTERED ID ] */ #define ETH_P_802_3_MIN 0x0600 /* If the value in the ethernet type is more than this value * then the frame is Ethernet II. Else it is 802.3 */ diff --git a/net/dsa/Kconfig b/net/dsa/Kconfig index 5ed8c704636d..d5e725b90d78 100644 --- a/net/dsa/Kconfig +++ b/net/dsa/Kconfig @@ -125,6 +125,16 @@ config NET_DSA_TAG_KSZ Say Y if you want to enable support for tagging frames for the Microchip 8795/937x/9477/9893 families of switches. +config NET_DSA_TAG_NETC + tristate "Tag driver for NXP NETC switches" + help + Say Y or M if you want to enable support for the NXP Switch Tag (NST), + as implemented by NXP NETC switches having version 4.3 or later. The + switch tag is a proprietary header added to frames after the source + MAC address, it has 3 types and each type has different subtypes, so + its length depends on the type and subtype of the tag, the maximum + length is 14 bytes. + config NET_DSA_TAG_OCELOT tristate "Tag driver for Ocelot family of switches, using NPI port" select PACKING diff --git a/net/dsa/Makefile b/net/dsa/Makefile index bf7247759a64..b8c2667cd14a 100644 --- a/net/dsa/Makefile +++ b/net/dsa/Makefile @@ -30,6 +30,7 @@ obj-$(CONFIG_NET_DSA_TAG_LAN9303) += tag_lan9303.o obj-$(CONFIG_NET_DSA_TAG_MTK) += tag_mtk.o obj-$(CONFIG_NET_DSA_TAG_MXL_862XX) += tag_mxl862xx.o obj-$(CONFIG_NET_DSA_TAG_MXL_GSW1XX) += tag_mxl-gsw1xx.o +obj-$(CONFIG_NET_DSA_TAG_NETC) += tag_netc.o obj-$(CONFIG_NET_DSA_TAG_NONE) += tag_none.o obj-$(CONFIG_NET_DSA_TAG_OCELOT) += tag_ocelot.o obj-$(CONFIG_NET_DSA_TAG_OCELOT_8021Q) += tag_ocelot_8021q.o diff --git a/net/dsa/tag_netc.c b/net/dsa/tag_netc.c new file mode 100644 index 000000000000..15b0dd5c5408 --- /dev/null +++ b/net/dsa/tag_netc.c @@ -0,0 +1,180 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2025-2026 NXP + */ + +#include + +#include "tag.h" + +#define NETC_NAME "nxp_netc" + +/* Forward NXP switch tag */ +#define NETC_TAG_FORWARD 0 + +/* To_Port NXP switch tag */ +#define NETC_TAG_TO_PORT 1 +/* SubType0: No request to perform timestamping */ +#define NETC_TAG_TP_SUBTYPE0 0 + +/* To_Host NXP switch tag */ +#define NETC_TAG_TO_HOST 2 +/* SubType0: frames redirected or copied to CPU port */ +#define NETC_TAG_TH_SUBTYPE0 0 +/* SubType1: frames redirected or copied to CPU port with timestamp */ +#define NETC_TAG_TH_SUBTYPE1 1 +/* SubType2: Transmit timestamp response (two-step timestamping) */ +#define NETC_TAG_TH_SUBTYPE2 2 + +/* NETC switch tag lengths */ +#define NETC_TAG_FORWARD_LEN 6 +#define NETC_TAG_TP_SUBTYPE0_LEN 6 +#define NETC_TAG_TH_SUBTYPE0_LEN 6 +#define NETC_TAG_TH_SUBTYPE1_LEN 14 +#define NETC_TAG_TH_SUBTYPE2_LEN 14 +#define NETC_TAG_CMN_LEN 5 + +#define NETC_TAG_SUBTYPE GENMASK(3, 0) +#define NETC_TAG_TYPE GENMASK(7, 4) +#define NETC_TAG_QV BIT(0) +#define NETC_TAG_IPV GENMASK(4, 2) +#define NETC_TAG_SWITCH GENMASK(2, 0) +#define NETC_TAG_PORT GENMASK(7, 3) + +struct netc_tag_cmn { + __be16 tpid; + u8 type; + u8 qos; + u8 switch_port; +} __packed; + +static void netc_fill_common_tag(struct netc_tag_cmn *tag, u8 type, + u8 subtype, u8 sw_id, u8 port, u8 ipv) +{ + tag->tpid = htons(ETH_P_NXP_NETC); + tag->type = FIELD_PREP(NETC_TAG_TYPE, type) | + FIELD_PREP(NETC_TAG_SUBTYPE, subtype); + tag->qos = NETC_TAG_QV | FIELD_PREP(NETC_TAG_IPV, ipv); + tag->switch_port = FIELD_PREP(NETC_TAG_SWITCH, sw_id) | + FIELD_PREP(NETC_TAG_PORT, port); +} + +static void *netc_fill_common_tp_tag(struct sk_buff *skb, + struct net_device *ndev, + u8 subtype, int tag_len) +{ + struct dsa_port *dp = dsa_user_to_port(ndev); + u16 queue = skb_get_queue_mapping(skb); + u8 ipv = netdev_txq_to_tc(ndev, queue); + void *tag; + + skb_push(skb, tag_len); + dsa_alloc_etype_header(skb, tag_len); + + tag = dsa_etype_header_pos_tx(skb); + memset(tag + NETC_TAG_CMN_LEN, 0, tag_len - NETC_TAG_CMN_LEN); + netc_fill_common_tag(tag, NETC_TAG_TO_PORT, subtype, + dp->ds->index, dp->index, ipv); + + return tag; +} + +static void netc_fill_tp_tag_subtype0(struct sk_buff *skb, + struct net_device *ndev) +{ + netc_fill_common_tp_tag(skb, ndev, NETC_TAG_TP_SUBTYPE0, + NETC_TAG_TP_SUBTYPE0_LEN); +} + +/* Currently only support To_Port tag, subtype 0 */ +static struct sk_buff *netc_xmit(struct sk_buff *skb, + struct net_device *ndev) +{ + netc_fill_tp_tag_subtype0(skb, ndev); + + return skb; +} + +static int netc_get_rx_tag_len(int rx_type) +{ + int type = FIELD_GET(NETC_TAG_TYPE, rx_type); + + if (type == NETC_TAG_TO_HOST) { + u8 subtype = rx_type & NETC_TAG_SUBTYPE; + + if (subtype == NETC_TAG_TH_SUBTYPE1) + return NETC_TAG_TH_SUBTYPE1_LEN; + else if (subtype == NETC_TAG_TH_SUBTYPE2) + return NETC_TAG_TH_SUBTYPE2_LEN; + else + return NETC_TAG_TH_SUBTYPE0_LEN; + } + + return NETC_TAG_FORWARD_LEN; +} + +static struct sk_buff *netc_rcv(struct sk_buff *skb, + struct net_device *ndev) +{ + struct netc_tag_cmn *tag_cmn = dsa_etype_header_pos_rx(skb); + int tag_len = netc_get_rx_tag_len(tag_cmn->type); + int sw_id, port; + + if (ntohs(tag_cmn->tpid) != ETH_P_NXP_NETC) { + dev_warn_ratelimited(&ndev->dev, "Unknown TPID 0x%04x\n", + ntohs(tag_cmn->tpid)); + + return NULL; + } + + if (tag_cmn->qos & NETC_TAG_QV) + skb->priority = FIELD_GET(NETC_TAG_IPV, tag_cmn->qos); + + sw_id = NETC_TAG_SWITCH & tag_cmn->switch_port; + /* ENETC VEPA switch ID (0) is not supported yet */ + if (!sw_id) { + dev_warn_ratelimited(&ndev->dev, + "VEPA switch ID is not supported yet\n"); + + return NULL; + } + + port = FIELD_GET(NETC_TAG_PORT, tag_cmn->switch_port); + skb->dev = dsa_conduit_find_user(ndev, sw_id, port); + if (!skb->dev) + return NULL; + + if (tag_cmn->type == NETC_TAG_FORWARD) + dsa_default_offload_fwd_mark(skb); + + /* Remove Switch tag from the frame */ + skb_pull_rcsum(skb, tag_len); + dsa_strip_etype_header(skb, tag_len); + + return skb; +} + +static void netc_flow_dissect(const struct sk_buff *skb, __be16 *proto, + int *offset) +{ + struct netc_tag_cmn *tag_cmn = (struct netc_tag_cmn *)(skb->data - 2); + int tag_len = netc_get_rx_tag_len(tag_cmn->type); + + *offset = tag_len; + *proto = ((__be16 *)skb->data)[(tag_len / 2) - 1]; +} + +static const struct dsa_device_ops netc_netdev_ops = { + .name = NETC_NAME, + .proto = DSA_TAG_PROTO_NETC, + .xmit = netc_xmit, + .rcv = netc_rcv, + .needed_headroom = NETC_TAG_MAX_LEN, + .flow_dissect = netc_flow_dissect, +}; + +MODULE_DESCRIPTION("DSA tag driver for NXP NETC switch family"); +MODULE_LICENSE("GPL"); + +MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_NETC, NETC_NAME); +module_dsa_tag_driver(netc_netdev_ops); -- 2.34.1